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Modern British & Irish Art Evening Sale
Artist's Resale Right ("Droit de Suite"). Artist's… Read more PROPERTY OF A LONDON COLLECTOR
Graham Sutherland, O.M. (1903-1980)
Still Life with Banana Leaf
signed with initials and indistinctly dated 'G.S. 1947' (lower right)
10½ x 21½ in. (26.5 x 53.5 cm.)
with Hanover Gallery, London.
Franland Dark, London.
with Marlborough Fine Art, London, circa the 1960s.
Anonymous sale; Sotheby's, 10 June 2014, lot 17.
R. Melville (intro.), Graham Sutherland, London, 1950, n.p., no. 52, illustrated.
D. Cooper, The Work of Graham Sutherland, London, 1961, p. 78, no. 99a, illustrated.
F. Arcangeli, Graham Sutherland, Milan, 1973, p. 35, no. 66, illustrated.
J. Hayes, The Art of Graham Sutherland, Oxford, 1980, p. 113, no. 80, illustrated
London, Hanover Gallery, Paintings by Graham Sutherland, June - July 1948, no. 15.
Artist's Resale Right ("Droit de Suite"). Artist's Resale Right Regulations 2006 apply to this lot, the buyer agrees to pay us an amount equal to the resale royalty provided for in those Regulations, and we undertake to the buyer to pay such amount to the artist's collection agent.
Painted in 1947, Still Life with Banana Leaf coincides with Sutherlands first visit to the South of France. In the summer of that year he and his wife Kathleen travelled from England, first to Paris and then onto Aix-en-Provence and the surrounding region, where they socialised with artist's such as Francis Bacon and Eardley Knollys of the Bloomsbury School. This trip was a seminal moment in the artist's career and Sutherland returned to work there for several months in the winter every year.
The direct influence of the French Riviera is notable in several aspects of Still Life with Banana Leaf, perhaps most obviously with the prop itself. The exoticism of the banana leaf, with its vibrant colour, large size, rubbery texture and it's impact on a British audience in the immediate post-war period must not be under-estimated. The present work is one of a series of still-lifes from this time, demonstrating Sutherland's preoccupation with the new subject matter that the Mediterranean region offered him. Palms, gourds, cicadas, and vines were all frequent motifs in Sutherland's works from 1947 and 1948. However, the spiky anthropomorphic shapes of both the palms and banana leaf that appears in these works do recall the organic themes of the gnarled hedgerows and thorn trees that had been prevalent in Sutherland's work prior to Second World War. In Still Life with Banana Leaf Sutherland is building upon his earlier organic influences with the exoticism of the French Riviera.
In 1951 Sutherland wrote 'Critics have said that my colour became light (and acid!) after I started working in France! It is a prime example of the laziness of some of them; if they had bothered to enquire I could have shown them pictures painted in 1944 which were very bright and light in colour' (G. Sutherland, ' Thoughts on Painting', The Listener, 1951, pp. 376-378). Nevertheless, it is difficult to dismiss that the almost luminous tones of the orange table and turquoise and green leaves were a direct reaction to the light, warmth and colours of the South of France.
In the years after the Second World War, Sutherland was keen to disassociate his work from being seen as that of a provincial Neo-Romantic and aspired to gain a greater international reputation. In a letter to New Statesman he writes 'I do not deny that I received adolescent stimulus from Palmer and Blake: but that does not mean I turn my back on Paris' (Sutherland, quoted in M. Hammer, Graham Sutherland: Landscapes, War Scenes, Portraits 1924-1950, London, 2005, p. 161). Still Life with Banana Leaf and other works of this period demonstrates a close affinity with French modernism. The spiky folds and segments of the leaves gives the work a partially shattered or fragmented appearance, this combined with the use of multiple view-point perspective and plains of bright flat colour are all aspects that are reminiscent of modernist painting from Paris, namely Picasso's Cubism and Matisse's Fauvism. During his pivotal trips to Paris in 1947, Sutherland was introduced to both of these artists, first Matisse at his home in Vence and then Picasso at Villauris, which was the beginning of a long relationship between the two artists.
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Why we changed our TV entertainment.
Since Antonio is autistic we had to change our way of doing things a little. The biggest thing was watching tv. What can he watch and when? If he throws a tantrum when I turn off the tv then he needs to understand that's not okay.
He can watch tv I'm not going to take that away from him, but we are much more strategic in what he is watching. He can only watch it for one hour and that's before bed time when he's winding down and drinking his milk!
We stopped watching Mickey Mouse. He loves it period. However, he appreciates when he can watch it now much more than ever before. He recognizes Mickey loves him. He still lights up when he sees anything Mickey and recognizes it quickly.
We only allow one hour of tv a day that's it! In that hour we watch Sesame Street or Curious George. At first neither of these interest Antonio, but it took sometime to get used to it and actually enjoy it. Here are a few reasons why we switched it over and loved it!
Both of these shows were much more learning interactive and educational. We learned the letter of the day and what that letter could be used for in real life. It grabbed his attention for longer periods.
They have realistic problem solving. With Mickey they always relied on toodles where as here it was about finding ways to do things on your own. Curious George is a great example of this because of the fact that he wasn't always smart but did problem solve.
They have really good catchy songs for learning. Antonio loves music and can instantly relate music to learning now. They have great catchy songs that are about learning .. "the letter of the day is.. " we love that song and he instantly stops for it!
Mickey he would get stimulated where as these ones were just about him watching it and sitting still.
These are both still cartoons but has everyday life lessons such as counting and letters and even daily routines etc. Your child can learn from them a lot, and I am happy that we have found these programs to learn from.
View some of our favorite items for autistic kids.
That's great for you and perfect reasons!


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Chaqataram (, also Romanized as  Chaqāţaram, Chagā Ţarm, Chaghāţūm, and Chogāţarm; also known as Chaghāţar) is a village in Pachehlak-e Sharqi Rural District, in the Central District of Aligudarz County, Lorestan Province, Iran. At the 2006 census, its population was 131, in 26 families.

References

Towns and villages in Aligudarz County

redpajama_set_name: RedPajamaWikipedia


I meant to publish this post weeks ago! I just put Chloe to sleep and I finally have some time to post this outfit from a couple weeks ago – before, the weather turned so sunny and hot!
Lately, or ever since giving birth I've only been sticking to oversize silhouettes. Recently, I realized I really need to hit the gym! But, that's another conversation. A printed or even a basic solid blouse thats a bit longer is perfect to pair with leggings. It's an easy outfit, especially when you need something quick to get out of the house!
Great style girl! I especially love those black ankle strap heels.


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MAJOR LANCE: Ain't No Soul (RPM)
Chicago's Major Lance was never a premier league soul player in the US. In the UK, however, it's a different story. In the mid sixties he became a mod cultural icon (and not just in London, as the sleeve notes would suggest) while a little later he became a revered legend on the Northern soul scene. Given that almost saintly status, it's odd that there aren't that many Lance quality compilations and reissues out there. Thankfully, Cherry Red imprint, RPM Retro is set to rectify that with a wonderful two CD, 53 track collection that pulls together (for the first time, I believe) all the recordings Major made for the fabled Okeh label… the high watermark of his career.
Born in either 1939, 1940 or 1941 (depending on what sources you use) Major Lance came to Okeh with the help of his long time pal, Curtis Mayfield. The pair had grown up together in Chicago's Cabrini-Green projects and indeed it was the "Gentle Genius" who helped kick start his friend's success at Okeh. Curtis supplied many of Lance's songs; he played guitar on the recordings; the Impressions sang BVs ( sometimes they were replaced by the Artistics); and he encouraged producer Carl Davis and arranger Johnny Pate to bring out the best in Major's quirky voice and to replicate the sonic template that the Impressions were enjoying success with. In essence Major Lance's early period Okeh recordings were Impressions records with a different lead voice; though, none the worse for that. Lance's big hits … 'The Monkey Time'. 'Um, Um, Um, Um, Um, Um', 'The Matador' and 'Rhythm' all featured sophisticated shuffle beats, sweet harmonies and insidious brass riffs but it was Major's unusual voice that proved the ultimate attraction.
By 1966, things started to change for Major and indeed Okeh. Curtis Mayfield was too busy with the Impressions and other projects to work with his old friend and master producer, Carl Davis left the company. Now teamed with New York's Ted Cooper, the Major Lance sound changed. It became more up-tempo and aped the Motown template. And why not? Through 1966 and '67 Motown were massive… why even Curtis had a go at the "sound" (grab a listen to the Impressions' 'You've Been Cheating'). So it was that Lance's recordings from this period ('It's The Beat', 'Investigate', 'Ain't No Soul (In These Old Shoes)', 'Too Hot To Hold' etc) became the stuff of Northern soul mythology.
All those fabulous tunes are here, naturally, but you get an awful lot more…. B sides, album tracks (many covers of Impressions songs) and hard to find collectables. The set's a must for anyone who really cares about proper soul music and though Major Lance went on to record for labels like Dakar, Curtom and Stax/Volt he never again created anything as magical and intoxicating as he did at Okeh. That was his time and place!
Major Lance died in 1994. He'd been in ill health for some time and after a ten year jail sentence for narcotics offences, he was relegated to the second division oldies circuit…. a sad end for a major soul talent!
(BB) 5/5

redpajama_set_name: RedPajamaCommonCrawl


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Q: on click event in wx.Panel? how can I click on a wx.Panel and that changes its color?
What is the name of the event.
(I want to do a similar thing as Firefox Extras)
Thanks in advance! :)

A: A quick google for wxpython mouse events turns up http://www.wxpython.org/docs/api/wx.MouseEvent-class.html
So using this, you could do something like:
class MyFrame(wx.Frame):
    def __init__(self):
        wx.Frame.__init__(self, None)
        self.panel = wx.Panel(self)
        self.panel.BackgroundColour = wx.RED
        self.panel.Bind(wx.EVT_LEFT_UP, self.onClick)

    def onClick(self, event):
        self.panel.BackgroundColour = wx.GREEN

redpajama_set_name: RedPajamaStackExchange


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Babi Yar Massacre
During the Great Patriotic War, German troops, who occupied Kiev on September 19, 1941, used Babi Yar as a place of mass executions.
According to some sources, in Babi Yar about one hundred and fifty thousand people (residents of Kiev and other cities of Ukraine) were shot. 29 people were saved from Babi Yar.
Babi Yar is in the northwestern part of Kiev, between the districts of Lukyanovka and Syrets. Babi Yar gained worldwide fame as the site of mass executions of civilians by the Nazis and Ukrainian collaborators, mainly of Jews, Roma, and Soviet prisoners of war, and carried out by the German occupation forces during the Second World War.
There are several monuments on the territory of Babi Yar, both to the victims of the Holocaust and to other Soviet citizens. Before the Kurenyov tragedy of 1961, there was one of the largest ravines in Kiev – about 2.5 km long, over 50 m deep. A stream of the same name flowed along its bottom, which is now taken into a collector.
Before the Great Patriotic War
It was first mentioned under its modern name in 1401, when the owner of the tavern (in Ukrainian "baba"), which was located here, sold these lands to a Dominican monastery. In the 15th-18th centuries, the names "Shalena Baba" and "Bisova Baba" were also encountered.
In 1869, a summer military camp was opened near Babi Yar – "Syretsk military camp". In 1895, the Divisional Church was opened on its territory, destroyed after the Bolshevik revolution. On the site of this church, there were later the gates of the Syrets concentration camp.
In 1870, the territory adjacent to Babi Yar from the south was used for the construction of the Lukyanovskoye civil cemetery (there is also the Lukyanovskoye military cemetery ). The cemetery was closed in 1962. Currently, the territory of the cemetery is a conservation area.
In 1891-1894, in the immediate vicinity of Babi Yar, a New Jewish cemetery (with a plot for the Karaites ) was created. It was closed in 1937 and destroyed during World War II. Only a small fragment of the cemetery and office has survived. The remaining burials were transferred in the 1960s to Baikovoye (section 49) and Berkovetskoye cemetery.
Since 1996 (for the first time in the publication of Holocaust denier T. Tur), there are claims that victims of the 1932-1933 famine and repression were buried on the territory of Babi Yar. As studies by T. Evstafyeva and V. Nakhmanovich show, those who died of starvation were buried at the nearby former Bratsk cemetery, and the repressed at the Lukyanovskoye cemetery and in Bykovna.
During the Great Patriotic War
The first execution took place on September 27, 1941 – 752 patients of the V.I. Ivan Pavlov, which was in close proximity to the ravine. The exact place of the execution is unknown.
On September 24, on Khreshchatyk, houses were blown up, in which representatives of the occupation administration were located. Explosions and fires continued in the following days, with about 940 large residential and office buildings destroyed. In the report of the representative of the imperial ministry of the occupied eastern regions of October 5, 1941, it was said that the fire spread over an area of 200 thousand square meters. About 50 thousand people were left homeless.
Babi Yar, analysis of the belongings of the deceased. Black and white copy of a color photograph by J. Hele
… Dina rushed about, ready to run, but there was noise and crying. An officer came, leading two girls, fifteen or sixteen years old. The girls screamed, sobbed, threw themselves on the ground and tried to kiss the officer's boots, begged to force them to do whatever they wanted, just not shoot them. They were in the same neat dark dresses, with pigtails. – We're from an orphanage! They shouted. – We do not know who we are by nationality. We were brought in as nurses! – The officer watched them roll around and moved his legs. I told them and Dinah to follow him. We went out to the same square where they were undressed. There were still heaps of clothes and shoes. Behind the things, on the sidelines, were thirty or forty old men, old women and the sick. That's right, these were the remains, caught in the apartments. One old woman lay paralyzed, wrapped in a blanket. Dina and the girls were seated with them. The girls were crying softly…
Babi Yar. Novel document (excerpt)
At the end of September 1941, the Sonderkommando captured nine leading rabbis of Kiev and ordered them to make an appeal: "After sanitation, all Jews and their children, as a nation, will be transported to safe places…" On September 27-28, the Nazi authorities issued an order that on September 29 the Jewish population of the city should appear at the designated collection point by 8 a.m. with documents and valuables. For non-observance of the order, they were supposed to be shot. About 2 thousand ads were posted around the city. At the same time, misinformation about the intention to conduct a census and resettlement of Jews was spread through the janitors and house managers. Most of those who came were women, children and old people (the adult male population was drafted into the army), in addition to Jews, there were representatives of other nationalities from international families.
At the end of the street, a checkpoint was set up, behind which there was an office hidden from the side. In turn, 30-40 people were taken outside the checkpoint, where their belongings were taken away and forced to undress. Then the policemen, with the help of sticks, drove people into the passages in the embankment at the edge of the ravine 20-25 meters deep. On the opposite edge was a machine gunner. After the ditch was filled with 2-3 layers of corpses, they were sprinkled with earth on top.
I stopped nearby, and the Ukrainians who were in the clearing began to load the car with things. From this place I saw that the arriving Jews – men, women and children – were also met by Ukrainians and directed to the place where they had to take turns to put their belongings, coats, shoes, outerwear and even underwear. In a certain place, the Jews had to put their jewelry as well. All this happened very quickly: if someone was delayed, the Ukrainians urged him on with kicks and blows. I think that not even a minute passed from the moment when the man took off his coat, until he was already completely naked. No distinction was made between men, women and children… The undressed Jews were sent into a ravine about 150 meters long, 30 meters wide and as much as 15 meters deep. There were 2 or 3 narrow passages leading into this ravine,on which the Jews descended. When they approached the edge of the ravine, the German police grabbed them and laid them on the corpses of the Jews who had already been shot there. This happened very quickly. The bodies lay in neat rows. As soon as the Jew lay down, a German policeman came up with a submachine gun and shot the man in the back of the head. The Jews descending into the ravine were so frightened by this terrible picture that they became completely weak-willed… It was a conveyor belt that did not distinguish between men, women and children. The children were left with their mothers and were shot together with them… In the pit I saw corpses lying three rows wide, each about 60 meters. How many layers lay one on top of the other, I could not make out. The sight of the bodies twitching in convulsions, covered with blood simply did not fit into my consciousness, so the details did not reach me… While some people were undressing,and the majority were waiting for their turn, there was a lot of noise.
The Ukrainians paid no attention to him. They continued in haste to drive people through the passages into the ravine. From the place where the undressing took place, the ravine was not visible, since it was at a distance of about 150 meters from the first group of clothes. In addition, there was a strong wind and it was very cold.
No shots were heard in the ravine… More and more people were arriving from the city and they, apparently, did not suspect anything, believing that they were simply being resettled.
From the testimony of the Wehrmacht driver Hefer
Since it was not possible to shoot all the arrivals in one day, the premises of military garages were used as a temporary detention center for those who arrived at night.
The surviving color photographs of J. Hele, taken shortly after the executions, did not make it possible to accurately identify the place, since the relief of the ravine changed greatly in the post-war period, especially after the Kurenevsky landslide of the 1960s. Nevertheless, a study carried out in 2020-2021 made it possible to compare photographs with aerial photographs of the same time and accurately localize all the places of events. .
For two days, 29 and 30 September 1941, Sonderkommando 4a under the command of Standartenfuehrer Paul Blobel (which was part of Einsatzgroup C under the command of SS Brigadefuehrer and Police Major General Otto Rasch ) with the participation of 45 and 303 battalions of the German police of the order of the police regiment South "and the Ukrainian auxiliary police shot 33,771 people in this ravine (this number does not include young children under 3 years old, who were also killed on these two days). Sonderkommando 4a and the 45th battalion of the German police of order took a direct part in the executions. Servicemen of the 303rd battalion of the German police of order stood in a cordon around the places of execution. The shootings did not stop there. Further executions of Jews took place on October 1 and 2, October 8 and October 11, 1941.
Russian husbands saw off their Jewish wives. Russian wives saw off their Jewish husbands. Approaching Babi Yar, we heard shooting and inhuman screams. I began to understand what was happening here, but I didn't say anything to my mother… When we entered the gate, we were ordered to hand over documents and valuables and undress. One German approached his mother and tore off a gold ring from her finger. I saw women, old men and children undressing group after group. Everyone is brought to an open pit, and the machine gunners shoot them. Then another group is brought in… I saw this horror with my own eyes. Although I was not quite close to the pit, I still heard the eerie cries of distraught people and the muffled voices of children calling: "Mom, mom…".
Testimony of Dina Pronicheva, Babi Yar survivor
The lack of housing, especially in Kiev, as a result of extensive fires and explosions, was palpable, but after cleansing of Jews it was eliminated thanks to moving into vacated apartments… On September 29 and 30, 31,771 Jews were specially treated…
Heinrich Müller. Report No. 6, dated October 31, 1941
Mass executions continued until the Germans left Kiev. On January 10, 1942, about 100 sailors of the Dnieper detachment of the Pinsk military flotilla were shot. Babi Yar became the place of execution of five gypsy camps.
According to various estimates, in Babi Yar in the period from 1941 to 1943, from 70,000 to 200,000 people were shot. Jewish prisoners, whom the Nazis forced to burn their bodies in 1943, spoke of 70-120 thousand.
In February – March 1942, 621 members of the Organization of Ukrainian Nationalists ( supporters of Andrey Melnyk ) and the poet Elena Teliga with colleagues from the newspaper "Ukrainian Word" were shot there. Historian and educator Ilya Levitas believes that they were killed in the dungeons of the Gestapo on Vladimirskaya Street.
In addition, on the site of the military camp of the Red Army units (the former military camp of the Russian Imperial Army ), the Syrets concentration camp was opened, which contained communists, Komsomol members, underground workers, prisoners of war and others. On February 18, 1943, three players of the Dynamo football team, participants in the so-called Death Match, were shot there : Trusevich, Kuzmenko and Klimenko (it was later confirmed that their deaths were not related to the game, but the legend in Death Match was composed to divert attention from the Jewish aspect of the Babi Yar tragedy. In total, at least 25,000 people died in the Syrets concentration camp.
An experimental soap factory was created in Babi Yar to produce soap from the dead, but the Germans did not manage to finish building it. Retreating from Kiev and trying to hide the traces of the crimes, the Nazis in August – September 1943 partially destroyed the camp, dug up and burned tens of thousands of corpses in open "ovens", the bones were ground in cars brought from Germany, the ashes were scattered around Babi Yar. On the night of September 29, 1943, an uprising of 329 death row inmates working at the furnaces took place in Babi Yar, of whom 18 people were saved, the remaining 311 were shot. The surviving prisoners witnessed the Nazis' attempts to hide the fact of the mass execution.
Executors of executions
The Einsatzgruppen Case established that the executions on September 29 and 30, 1941 in Babi Yar were carried out by Sonderkommando 4a of the Eiznatzgruppa C under the leadership of SS Standartenfuehrer Paul Blobel with the support of the 45th and 303rd battalions of the German police (German Polizei-Bataillon) of the order of the police regiment "South". These units were reinforced by units of the auxiliary police of Ukraine and supported by local collaborators.
In the journalistic articles of various authors, one can find non-documented information about the participation of Ukrainian nationalists in the executions, in particular, the Bukovyna kuren (which was not in Kiev at that time). According to the testimony of Paul Blobel during the tribunal and after confirming 106 of the Einsatzgruppen report, the Ukrainian militia (police) posted an advertisement in Kiev. In addition, the Germans in the occupied territories armed the Ukrainian auxiliary police with a very limited number of rifles and cartridges for them, not including the machine guns from which the executions were carried out in Babi Yar.
Trials of the guilty
Major General Kurt Eberhard, who gave the order for the execution, was not convicted – he committed suicide in 1947 in Stuttgart. Head of the Sonderkommando «4a» Paul Blobel was sentenced in 1948 to death by hanging and executed in 1951 in Landsberg prison. Kiev Police Commandant Andrey Orlik (real name Anatoly Konkel) was fired from the police shortly after the September executions. At the end of the war, under the name Anatoly Orlik, he served in the SS "Galicia" division with the rank of centurion, was captured by the Western allies and was in a camp in Rimini (Italy). Subsequently, like many other divisional men from the camp in Rimini, Anatoly Konkel left for Great Britain, where he lived under the name Anatoly Orlik and died in Birmingham in May 1989, at the age of ninety.
The General Commissioner of Kiev Helmut Kwitzrau was not brought to justice, he died in 1999.
Otto Rasch, the head of the Einsatzgruppen C under whose leadership the massacres of Jews at Babi Yar were carried out, was arrested after the war and charged as a defendant in the Einsatzgruppen case. The case against Rush was dropped due to Parkinson's disease.
From 1967 to 1968, former employees of the Sonderkommando 4a were tried at the Darmstadt Regional Court. The main defendant, Kuno Kallsen, was sentenced to 15 years in prison, Kurt Hans and Adolf Janssen to 11 years, August Hefner to 9 years, Victor Voiton to 7 years, Christian Schulte to 4 years and 6 months in prison, Alexander Riesle to 4 years in prison. Georg Pfarrkircher, Ernst Konzee and Viktor Trill were released under §47 of the German Penal Code.
Former SS Sturmbannfuehrer and commander of the 45th Police Battalion Martin Besser was not prosecuted for health reasons.
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As an avid ice skater and as someone who has recently become more interested in cross country skiing, I have decided to do my best to push the benefits of recreational sports for blind persons. Here in Toronto where I live, I have found it extremely difficult to find ways to engage in recreational sports and I am definitely not alone in my opinion.
Over the past year, I have spoken to several other blind persons who feel the same way. We have approached countless sporting organizations, volunteer groups, church groups, plus individuals and at the end of the day it is all the same message that we seem to be getting. It appears that the Federal government is more than willing to fund competitive sports for persons with disabilities, including blind and sight impaired persons but when it comes to recreational sports, there seems to be a huge hole; something like nothing beyond the deep blue sea or horizon.
Maybe it's time that we start to campaign for the benefits of recreational sports for blind and sight impaired persons. With a rapidly aging population, many of whom will probably lose varying degrees of vision along the way, it may be time for the various organizations and governmental bodies to start putting meaningful recreational sports programs into place. I hope that there are others out there who will hear my call and join the chorus.


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REVIEW: Mechanisms of Phototransformation of Protochlorophyllide into Chlorophyllide
O. B. Belyaeva* and F. F. Litvin
Lomonosov Moscow State University, Faculty of Biology, 119992 Moscow, Russia; fax: +7 (495) 939-4309; E-mail: belyaeva0104@gmail.com
The purpose of this review is to summarize and discuss data obtained in studies on the mechanisms of the primary photophysical and photochemical reactions of protochlorophyllide photoreduction in plant materials (etiolated leaves and leaf homogenates) and in model systems. Based on the results of numerous studies, it can be stated that the reduction of active forms of the chlorophyll precursor is a multistep process comprising two or three short-lived intermediates characterized by a singlet ESR signal. The first intermediate is probably a complex with charge transfer between protochlorophyllide and the hydride ion donor NADPH. The conserved tyrosine residue Tyr193 of protochlorophyllide oxidoreductase is the donor of the second proton.
KEY WORDS: chlorophyll, protochlorophyllide, photoreduction, non-fluorescent intermediates, fluorescence spectra, absorption spectra
Abbreviations: Chl, chlorophyll; Chld, chlorophyllide; Pchl, protochlorophyll; Pchld, protochlorophyllide; POR, protochlorophyllide oxidoreductase.
The final light-dependent stage of chlorophyll biosynthesis in plant leaves involves photoreduction of its immediate precursor protochlorophyllide and a range of light and dark reactions leading to the formation of the system of functional chlorophyll forms of the two photosystems of photosynthesis. Phototransformation of protochlorophyllide into chlorophyllide includes the addition of two hydrogen atoms in positions C17 and C18 of the tetrapyrrole protochlorophyllide molecule, the double bond being replaced by a single bond (Fig. 1). The high efficiency of this photoreaction in etiolated leaves is due to the fact that it proceeds within the photoactive complex emerging in etiolated leaves at the preceding stage of chlorophyll precursor synthesis in the dark. The active complex includes protochlorophyllide, the hydrogen donor NADPH, and the photoenzyme protochlorophyllide oxidoreductase (POR) (see review [1]). The structure of the active ternary complex creates spatial relations between protochlorophyllide and hydrogen donors favorable for the photoreduction reaction. The POR photoenzyme catalyzes the reaction. The photoenzyme as well as the protochlorophyllide of etioplasts are in an aggregated, most likely a dimeric state.
Fig. 1. Structural formulas of protochlorophyll(ide) (a) and chlorophyll(ide) (b) molecules. R1 corresponds to CH2–CH3 for the monovinyl pigment form and CH=CH2 for the divinyl form. R2 corresponds to C20H39 for protochlorophyll and chlorophyll and to hydrogen atom for protochlorophyllide and chlorophyllide.
There are several spectrally different forms of protochlorophyllide in both etiolated and green plant leaves (see review [1]). Pchld633/628, Pchld643/637, and the usually dominant Pchld655/650 are the main protochlorophyllide forms (the numbers show the position of fluorescence and absorption maxima). Several minor long-wave forms have also been found. Pchld655/650 is the main active form of protochlorophyllide; it is due to the transformation of this form that the bulk chlorophyll is synthesized.
Low temperature spectroscopy and high temporal resolution spectroscopy have shown that the photoreduction of protochlorophyllide is a rather complex process involving several fast light and dark reactions.
SHORT-LIVED INTERMEDIATES OF PROTOCHLOROPHYLLIDE PHOTOTRANSFORMATION INTO CHLOROPHYLLIDE in vivo STABILIZED AT LOW TEMPERATURES
Non-fluorescent intermediate X690. Studies of protochlorophyllide photoreduction in vivo (in etiolated leaves) at very low temperatures, when biochemical temperature-dependent stages are inhibited, reveal information on the mechanism of this reaction. The fluorescence quantum yield of the active protochlorophyllide form was found to decrease after leaves are illumination at low temperature (77-173 K) without the appearance of any new fluorescence bands. Subsequent increase in temperature in the dark causes the appearance of fluorescence bands characteristic for chlorophyllide. It was suggested that exciting light at low temperature causes the protochlorophyllide molecule to enter an intermediate state (non-fluorescent intermediate) that is transformed into chlorophyllide due to the next dark reaction proceeding on raising the temperature [2-14]. Photoinduced fluorescence quenching proceeds even at liquid helium temperature [12], indicating the elementary photophysical nature of the primary reaction.
The absorption band of the non-fluorescent intermediate that is stabilized at low temperatures is at about 690 nm [15]. The similar position of the maximum absorption of the primary intermediate was later registered also at room temperature [16, 17]. This intermediate is commonly called X690. In the dark increasing temperature causes X690 to turn into chlorophyllide:
Existence of several short-lived non-fluorescent intermediates. Studies of the primary stages of protochlorophyllide photoinduction at very low temperatures suggested the existence of even earlier stages of the photochemical reaction than the formation of the X690 intermediate. This is evidenced by comparison of the spectral pattern changes after illumination of etiolated leaves at different temperatures [9-11, 18-21] (Fig. 2).
Fig. 2. Fluorescence quenching as the primary act of photoreduction of the active form of protochlorophyllide. Changes in low-temperature (77 K) fluorescence spectra of etiolated bean leaves after illumination with light of 104 W/m2 at low temperatures (4.2, 77, 153 K): 1) unilluminated etiolated leaf; 2) the same leaf after illumination at low temperature (temperature indicated in the upper part of the figure); 3) the same sample after warming to 233 K (10 min) in the dark; 4) the same sample after warming to 263 K (20 min) in the dark.
The initial reaction, photoinduced fluorescence quenching of the active form of protochlorophyllide Pchld655/650, observed at low temperatures, becomes reversible when the temperature increases. The degree of reversibility depends on the temperature conditions during the illumination (75-80% after illumination at 4.2 K; 30-50% after illumination at 77 K; 5-6% after illumination at 153 K). The quantum yield of photoinduced quenching of protochlorophyllide Pchld655/650 fluorescence on deep cooling of etiolated leaves is very low (three orders of magnitude lower than the quantum yield of its photoreduction at room temperature); its dependence on temperature is rather weak in the range from 4.2 to 180 K. It is practically unaltered by increasing the temperature of the illuminated sample from 4.2 to 77 K and is slightly increased (50%) at 153 K (Fig. 2). The quantum yield of the following reaction, formation of the primary fluorescent chlorophyllide forms after the increase in temperature of illuminated samples, is characterized by higher dependence on the temperature at which the sample was illumination. This parameter (in contrast to the quantum yield of fluorescence quenching) changes significantly with increase in temperature of the illuminated leaves from 4.2 to 153 K. The quantum yield of the overall reaction (fluorescence quenching plus subsequent chlorophyllide formation after temperature increase) in leaves illuminated at 4.2 K, is three to four times lower than in leaves illuminated at 77 K, and it is ten times lower than when illuminated at 153 K.
These facts indicate greater complexity of the primary reaction: the existence of reverse reactions in the pathway of the formation of the X690 intermediate, these reactions being less dependent on temperature than the direct process of transformation of the non-fluorescent intermediate into chlorophyllide.
Fluorescence and absorption spectroscopy revealed that the primary photoreaction of protochlorophyllide transformation into a non-fluorescent intermediate is photoreversible when affected by a powerful monochromatic laser beam with wavelength of 694 nm (corresponds to the absorption of the X690 intermediate) [22, 23]. Rate constants and quantum yields of the direct and reverse photoreactions at photostationary equilibrium were calculated. The calculations showed that the photoreversibility of the reaction of X690 formation cannot be the reason for the low quantum yield of the general process as the quantum yield of the reverse process is substantially (about 20 times) lower. Since X690 formation is not reversible in the dark, the authors suggested the existence of another intermediate preceding X690 formation, which includes a fast reverse reaction; it is this reaction that reduces the yield of the overall process. The putative intermediate was designated as R (reversible):
These data explain the decrease in the reaction quantum yield at low temperature compared to the quantum yield at room temperature, when the quantum yield is close to 0.5 [24, 25]. Temperature increase causes the rate constants of direct dark processes to increase more rapidly than the rate constants of the reverse reactions, which is accompanied by the increase in overall yield of the process of chlorophyllide formation.
Analysis of spectral changes (Fig. 3) suggests that the absorption spectrum of the primary intermediate R predominantly formed at 77 K is close (if not identical) to the absorption spectrum of the active protochlorophyllide form: the primary effect of light on etiolated leaves, manifested by quenching of protochlorophyllide fluorescence, is observed under the conditions when X690 is practically unnoticeable in absorption spectra (at 80% fluorescence quenching the absorption spectrum remains virtually unchanged) [18, 19]. The 10-12% decrease in the protochlorophyllide absorption band and the appearance of a long-wavelength absorption maximum at 690 nm belonging to the non-fluorescent X690 intermediate are observed in the absorption spectra of leaves illuminated at 153 K.
Fig. 3. Changes in low temperature (77 K) fluorescence (a) and absorption (b) spectra of etiolated bean leaves illuminated with intense white light (104 W/m2) at low temperatures: solid line, unilluminated etiolated leaf; dotted line, after 4 min illumination at 77 K; dashed line, after 4 min illumination at 153 K.
Data of time-resolved spectroscopy obtained at room temperature indicate the appearance of a short-lived intermediate with absorption band close to the absorption band of the active protochlorophyllide form, in the chain of protochlorophyllide transformations [26, 27].
Low-temperature (77 K) optical (absorption and fluorescence) and ESR spectra of entire etiolated and illuminated leaves were studied to elucidate the mechanism of the early stages of protochlorophyllide photoreduction [18, 19, 21]. Both short-lived intermediates, R and X690, were shown to be paramagnetic. Leaves illumination at 77 K (when non-fluorescent intermediate R is mainly formed) was found to cause the emergence of a structureless singlet ESR signal with g-factor 2.0021 characteristic of a free electron, width 1.1 mT. Increasing temperature to 200 K caused a slight increase in the amplitude of the ESR signal of etiolated leaves illuminated at 77 K (Fig. 4). This increase in the signal amplitude probably corresponds to the transformation of the primary product R into intermediate X690. Decrease in the signal width was observed along with amplitude increase. Further increase in temperature above 200 K caused a sharp drop in the ESR signal amplitude, which reached the initial dark value at the temperature of about 250 K. Absorption and fluorescence spectra showed the formation of the primary forms of chlorophyllide along with the sharp decline of the ESR signal amplitude of etiolated leaves illuminated at 77 K on increasing the temperature.
Fig. 4. ESR spectral study to clarify the nature of the non-fluorescent intermediates [18, 19, 21]. Changes in the ESR signal of an etiolated bean leaf illuminated for 4 min with white light with intensity 104 W/m2 at 77 K after gradual increase in temperature in the spectrophotometer. a) Changes in the ESR spectrum: 1) unilluminated leaf; 2) after illumination at 77 K; 3-6) after temperature increase; b) changes in the amplitude of the ESR signal of the leaf illuminated at 77 K depending on the temperature increase; c) changes in the width of the ESR signal of the leaf illuminated at 77 K depending on the temperature increase.
Thus, the primary intermediate R resulting from the photoreaction itself is close in its absorption spectrum to the original protochlorophyllide form, but it differs from it in having a very low fluorescence quantum yield. Intermediate R is characterized by a singlet ESR signal with the g-factor of a free electron. Increasing the temperature at which the sample is illuminated causes an increase in the rate constant of the direct reaction of the transformation of intermediate R into X690. Non-fluorescent intermediate X690 is also characterized by a singlet ESR signal with g-factor 2.002 characteristic of a free electron, but it has a narrower signal width of 0.95 mT.
Two forms of a non-fluorescent intermediate X690. It was noted in several studies that the non-fluorescent intermediate X690 is characterized by a broad absorption band at 680-710 nm [5-8]. The position of the absorption maximum was shown to depend significantly on the temperature during the illumination. Illumination at 153-158 K was accompanied by the appearance of a wide absorption band at 705 nm, while illumination at 158-163 K resulted in a band with maximum at 689 nm [8].
Differential and derivative spectroscopy revealed the existence of two forms of X690 characterized by absorption maxima at 697 and 688 nm and different formation rates (Fig. 5) [28]. The intermediates were named R697 and R688. The R697 intermediate could be detected after a brief illumination of etiolated leaves at 77 K. The intensity of the absorption band of the active protochlorophyllide form at 650 nm remained practically unchanged. Subsequent increase in the temperature of the sample in the dark to 233 K led to the complete reversibility of the reaction of R697 formation. The R688 intermediate was accumulated more slowly; this process was accompanied by a decrease in the absorption band of the active protochlorophyllide form at 650 nm. Reduction of the band at 650 nm indicates more profound changes in the protochlorophyllide molecule at this stage when compared to the previous stage of intermediate R697 formation, when absorption at 650 nm remains unchanged. Judging from ESR spectra, both R697 and R688 intermediates are paramagnetic. Increasing the temperature of a sample characterized by two absorption bands in the difference spectrum at 697 and 688 nm to 233 K caused both the effective reverse reaction of the intermediates into protochlorophyllide and the forward reaction of formation of the primary chlorophyllide forms with absorption maxima at 676 and 684 nm. Since the formation of the chlorophyllide primary forms (at higher temperature) required joint accumulation of two non-fluorescent intermediates R697 and R688, these intermediates were suggested to be formed in parallel photoreactions, but at different rates; increasing temperature causes interaction of their chromophores leading to the formation of a chlorophyllide molecule by a mechanism of free radical disproportionation. This assumption about the mechanism of chlorophyllide formation by free radical disproportionation was suggested earlier in [8].
Fig. 5. Two forms of non-fluorescent intermediate X690. Low-temperature differential absorption spectra of etiolated barley leaves: 1) spectrum of a sample illuminated for 5 s at 77 K minus spectrum of the same sample prior to illumination; 2) spectrum of a sample illuminated for 1 min at 77 K minus spectrum of the same sample prior to illumination; 3) spectrum of a sample after illumination for 1 min at 77 K and its subsequent incubation at 233 K in the dark for 15 min minus the spectrum of the sample illuminated for 1 min at 77 K. Light intensity 102 W/m2 [28].
At the end of this section, we conclude that protochlorophyllide photoreduction in vivo includes at least two elementary reactions that can be registered by spectroscopic methods at very low temperatures, when the products of these reactions, non-fluorescent intermediates, are stabilized:
STUDY OF FAST STAGES OF PROTOCHLOROPHYLLIDE PHOTOREDUCTION in vivo AT PHYSIOLOGICAL TEMPERATURES
Study of chlorophyll photobiosynthesis in etiolated leaves by time-resolved spectroscopy is another way to detect labile short-lived intermediates of protochlorophyllide photoreduction. Application of this method has revealed the formation of short-lived intermediates also at physiological temperatures. Studies of the kinetics of the changes in pigment fluorescence intensity after brief illumination of etiolated leaf homogenates [29], as well as fast light-induced absorption spectral changes of leaves and isolated pigment–protein complexes [16, 17] at room temperature revealed a primary short-lived (0.2 μs) intermediate with absorption maximum at 690-695 nm.
Nanosecond and picosecond absorption spectroscopy [26] showed that the reaction of protochlorophyllide photoreduction in isolated pigment–protein complexes at room temperature involves four intermediates with time constants of formation of 5 ps, 2 ns, 35-250 ns, and 1-2 μs and the subsequent appearance of chlorophyllide at 12 μs:
The position of the absorption maximum of the primary product X0 is virtually identical to the position of the absorption band of the initial protochlorophyllide. The time constant of X0 formation corresponds to the relaxation of the protochlorophyllide molecule from the Franck–Condon state (S1*) to the equilibrium state (S1), hence X0 cannot be an intermediate in the chemical sense. Using the flash-photolysis method, it was shown that the absorption maximum of the X1 intermediate is also close to the absorption maximum of the initial protochlorophyllide (≥640 nm). Studies of the changes in differential absorption spectra have shown that intermediates X2 and X3 are characterized by absorption maxima at 688 and 684 nm, respectively. The authors of [26] suggested that intermediate X3 corresponds to the non-fluorescent intermediate X690 discovered in etiolated leaves illuminated at low temperatures. However, according to other researchers [30, 31], intermediate X690 rather corresponds to the X2 intermediate discovered by Iwai et al., as evidenced both by the absorption spectrum of this intermediate (maximum at 688 nm) and by the time of its formation (35-250 ns), which is comparable to the formation time of the X690 intermediate recorded by other researchers [16, 32]. Intermediate X1 [26] probably corresponds to the intermediate R discovered in our work [22, 23], as evidenced by the similarity between its absorption spectrum and the absorption spectrum of the initial protochlorophyllide. Intermediate X3 can be compared to one of the primary chlorophyllide forms appearing after temperature increase of etiolated leaves that were illuminated at 77 K.
Comparison of the results of research of intermediate stages of protochlorophyllide photoreduction in vivo at physiological and low temperatures showed that this process involves several intermediate products, including two or three short-lived intermediates that, according to our studies, are characterized by significant quenching of protochlorophyllide fluorescence.
PRIMARY FLUORESCENT CHLOROPHYLLIDE FORMS in vivo
The non-fluorescent intermediate X690 formed by light at low temperatures transforms into chlorophyllide following a dark path after increasing the temperature of the illuminated sample. When using white light for illumination of etiolated leaves at 77 K, subsequent increase in temperature caused almost simultaneous formation of two primary chlorophyllide forms with fluorescence maxima at 684 and 695 nm and corresponding absorption bands at 676 and 684 nm [9, 10, 33]. Then the Chld685/684 form turns into a shorter-wavelength form Chld684/676 during a dark reaction. The ratio of the bands at 695 and 684 nm appearing after illumination at low temperature depends on the spectral composition of the light. Blue light (with maximum at 470 nm) used for illumination resulted (after temperature increase) in the formation of only one band at 695 nm, which gradually shifts to 684 nm. Red light (>600 nm) used for illumination of leaves resulted (after temperature increase) in the appearance of only one shorter-wavelength maximum at 684 nm. Formation of only one, shorter-wavelength primary chlorophyllide form was observed in etioplast preparations. These data suggest the existence of two types of active protochlorophyllide–protein complex with nearly identical absorption and fluorescence bands in the red spectral region in etiolated leaves. Both forms are converted to chlorophyllide through the formation of a non-fluorescent intermediate. One of the precursors can be transformed directly into the shorter-wavelength chlorophyllide form Chld684/676. The hypothetical reaction scheme is as follows:
An additional active protochlorophyllide form Pchld653/648, close in its spectral characteristics to the main active form, was later discovered in vivo [34, 35]. Moreover, it is possible that the second pathway is based on the transformation of a shorter-wavelength form of the precursor Pchld643/637, whose fluorescence is quenched as a result of highly effective energy migration to the main active form.
The primary reactions of protochlorophyllide photoreduction in plant leaves were studied by means of time-resolved fluorescence spectroscopy [32]. The results of these studies have shown that dark transformation of non-fluorescent intermediates leads to the formation of four primary chlorophyllide forms characterized by fluorescence maxima at 684, 690, 695-697, and 706 nm. Similar results were obtained when studying primary fluorescent chlorophyllide forms by differential spectroscopy and dividing difference fluorescence spectra into Gaussian components [33]. It was found that the long-wavelength primary chlorophyllide forms with fluorescence maxima at 696 and 706 nm are later transformed at room temperature into shorter-wavelength forms with fluorescence maxima, respectively, at 675 and 684 nm. The form with fluorescence maximum at 684 nm is probably the chlorophyllide (Chld684/676) form, which serves as the initial form in the biosynthetic pathway of the pigments of the reaction center of photosystem II and the light-harvesting complex (see review [36]). Apparently, the formation of several primary labile chlorophyllide forms indicates the early differentiation of the pathways of the formation of functionally different native pigment forms.
PROTOCHLOROPHYLL(IDE) PHOTOREDUCTION IN MODEL SYSTEMS
Photoreactions in protochlorophyll solutions. Studying the reaction of protochlorophyll photoreduction in simple systems has become another way to elucidate the mechanism of the primary stages of chlorophyll biosynthesis from the precursor and the role of biological structures in this process. Studying protochlorophyll(ide) phototransformation in vitro reveals the spectral changes associated with the transformation of the actual chromophore molecule.
Many researchers have tried to photoreduce protochlorophyll(ide) to chlorophyll(ide) in vitro. The earliest systematic studies in this direction were carried out in the laboratory of Academician A. A. Krasnovsky using different model systems (solutions, solid films, pigment micellar solutions). As a result, rather high photoreaction product yield could be achieved (up to 20%), the product being identified as chlorophyll [37-39]. However, in these experiments the reaction was complicated by side processes, in particular, by photoreduction in the system of conjugated bonds of the chromophore. The primary reaction stages and its mechanism remained unclear. The singlet ESR signal, which was thought to belong to the pigment radical-anion, was discovered when studying protochlorophyll photoreduction by strong reducing agents in solutions at low temperatures (243-183 K) [40]. However, the character of the absorption spectrum changes indicated that in this case the reduction occurred in the system of conjugated bonds (with the formation of a "red" intermediate product).
To obtain information about the mechanism of the earliest stages of protochlorophyll(ide) photoreduction reactions, previously studied in whole leaves, we together with K. N. Timofeev and M. I. Bystrova studied this process in model systems [18, 19, 41]. Experimental conditions were as close as possible to those in the studies on plant leaves, when primary stages of photoreduction of the protochlorophyllide molecule could be observed (high intensity short illumination at 77 K). It was shown that primary photophysical stages of protochlorophyll reduction in solutions and films could proceed also without the use of reducing agents. Apparently, it is the solvent (ethanol, ethyl ether, pyridine) that serves as the hydrogen donor in this case.
Photoreduction of monomeric protochlorophyll(ide). The effect of quenching of fluorescence at 626 nm belonging to the monomeric pigment form was discovered when studying dilute solutions of protochlorophyll and protochlorophyllide in ethyl ether (10–6 M) after illumination of the samples at 77 K. This effect could be practically completely reversed by subsequent temperature increase to 273 K. The absorption spectrum remained unchanged [41]. A singlet signal with g-factor of 2.0013 and singlet band-width of 1.2 mT could be registered in the ESR spectrum simultaneously with protochlorophyllide fluorescence quenching; increasing temperature caused rapid disappearance of this signal and reappearance of fluorescence [18, 19]. Addition of reducing agents accelerated the fluorescence quenching several-fold.
Thus, illumination at 77 K caused the formation of a product close in the position of its red absorption band to the initial pigment, but different from it in low fluorescence yield and the appearance of a singlet ESR signal in low-concentration solutions of monomeric protochlorophyll. Increasing temperature caused disappearance of the product, which turned back into the initial compound. Comparison with the precursor photoreduction in whole etiolated leaves indicates that apparently the very first stage of chlorophyll precursor photoreduction is reproduced in the model systems with monomeric protochlorophyll; this stage is manifested in vivo in the quenching of fluorescence of the active protochlorophyllide form and the formation of the paramagnetic intermediate R.
Photoreduction of aggregated protochlorophyll. Absorption and fluorescence spectra of the three main native forms of chlorophyll precursor are rather well simulated in concentrated (10–4 M) ethanolic solutions of protochlorophyll: absorption bands at 625, 635, and 645-647 nm and fluorescence bands at 627, 637, and 651-652 nm are observed. According to [42, 43], the short-wavelength maxima at 627 and 636 nm belong to singly and doubly solvated pigment, respectively. Measurements of the circular dichroism spectra of protochlorophyll in model systems [44, 45] indicate that the longest-wavelength spectral band at 651-652 nm results from the formation of pigment dimer.
Illumination of the concentrated ethanolic solution at 77 K leads to the quenching of all the fluorescence bands [18, 19, 41]. This quenching proved to be reversible on increasing the temperature for two shorter-wavelength bands (similar to the experiments with the pigment monomer), whereas fluorescence intensity for the band at 651 nm could not be fully recovered. Light caused the appearance of a singlet signal with g-factor of 2.0015 and width of 1.1 mT in the ESR spectrum (these parameters match those of the signal caused by illumination of etiolated leaves). Along with fluorescence quenching, a small maximum at about 685-690 nm is observed in the low-temperature absorption spectrum; this maximum is close in its position to the absorption maximum of the non-fluorescent intermediate X690 discovered in plant leaves. Hence, deeper protochlorophyll transformation is apparently taking place in the systems with aggregated protochlorophyll (when compared to the monomeric pigment), comprising the formation of a chlorophyll-like product, which may be identical to the X690 intermediate. The aggregated long-wavelength form of the pigment is obviously involved in this stage of the process.
Thus, the similarities between the primary stages of protochlorophyll(ide) photoreduction in vivo and its most simple photoreactions in model systems suggest that primary photoreactions observed in whole leaves are really connected to the changes in the actual pigment molecule.
PROTOCHLOROPHYLLIDE PHOTOREDUCTION IN RESTORED TERNARY COMPLEXES
In recent years, a growing number of researchers have been using artificial ternary complexes to study the mechanism of the protochlorophyllide photoreduction reaction; these complexes include protochlorophyllide, NADPH, and the photoenzyme protochlorophyllide oxidoreductase. Pchld644/642 [14, 27, 46, 47] is the main active protochlorophyllide form in such systems; its spectral properties are close to those of the active protochlorophyllide form Pchld643/639 from whole etiolated leaves and to the main form that can be found in isolated pigment–protein complexes.
Similarly to a whole etiolated leave, the formation of an unstable non-fluorescent intermediate was registered on protochlorophyllide photoreduction in artificial ternary complexes at low temperatures; this intermediate proved to be the primary product that appears after illumination of samples at low temperatures [14, 47, 48], with the absorption band at about 696 nm [14]. Fluorescence quenching was accompanied by the appearance of a singlet signal with g-factor of a free electron in the ESR spectrum [46, 48]. Increasing temperature caused the non-fluorescent intermediate to change spontaneously into chlorophyllide, which was identified both by spectral characteristics [48] and by liquid chromatography [46]. The primary fluorescent intermediate was transformed into a shorter-wavelength chlorophyllide form in a dark reaction:
Formation of a non-fluorescent intermediate X696 can proceed at temperatures below 200 K, a critical temperature below which there are no dynamic enzyme changes. Hence, enzyme movement or reorganization is not involved in this stage of the catalytic mechanism. The temperature limit of X696 formation is 120 K. These data correlate with the results of studies on the temperature dependence of X690 formation in whole etiolated leaves; it was already mentioned that in these leaves frozen to 77 K there could be observed only protochlorophyllide fluorescence quenching accompanied by the formation of the first intermediate R with spectral properties virtually identical to those of protochlorophyllide.
Impulse techniques revealed the primary processes in reconstructed active complexes and at room temperature [27]. A slight increase in the initial protochlorophyllide absorption (maximum at 642 nm) with its shift to 636 nm could be observed in the time interval between 3 and 400 ps after illumination of the sample with a 50 fs laser flash (475 nm). At the same time, there also appeared a weak maximum at about 677 nm. A short-lived intermediate with absorption bands at 636 and 677 nm was transformed into chlorophyllide:
As mentioned above, the primary non-fluorescent intermediate formed by the action of light in living systems is similar to the initial protochlorophyllide in terms of the location of the main absorption maximum and its intensity. This could be observed both at low temperature – intermediate R formed at 77 K in whole leaves [19, 23] – and at room temperature in isolated pigment–protein complexes – formation of intermediate X1 [26]. It should be noted that a very slight short-wavelength shift of absorption maximum of the active protochlorophyllide form (650 nm) can also be found in absorption spectra of whole etiolated leaves briefly illuminated at 77 K [19] (this shift at first remained unnoticed). Probably, the Int (636, 677 nm) intermediate found by Heyes et al. [27] at room temperature in the picosecond time range corresponds to the simultaneous observation of two primary intermediates found in vivo: intermediate R (X1) and the next intermediate X690 (X2); the formation time of the latter at room temperature (35-250 ns) corresponds to the rate of primary intermediate formation in reconstructed complexes.
Spectral differences between the short-lived intermediate with absorption maximum at 675-677 nm discovered at room temperature and the X696 intermediate observed at low temperatures can be probably explained by different states of the protein part of the complex at low and high temperatures. The non-fluorescent intermediate X696 is formed on the deep freezing of the complex to a temperature below the critical value of 200 K, when dynamic changes in the enzyme start. At room temperature the pigment photoreduction proceeds along with protein conformational changes.
Thus, protochlorophyllide photoreduction in reconstructed ternary complexes proceeds in at least in two stages: light-induced formation of the short-lived non-fluorescent intermediate characterized by a weak ESR signal with g-factor of a free electron, and its subsequent dark transformation into chlorophyll. The observed processes are similar to those in whole etiolated leaves.
POSSIBLE MECHANISMS OF PHOTOREDUCTION OF THE PROTOCHLOROPHYLLIDE MOLECULE
In our early studies [9, 10] we suggested that the primary reactions of protochlorophyllide photoreduction in vivo characterized by the formation of paramagnetic intermediates correspond to the sequential transfer of two electrons and two protons to the semi-isolated double bond C17=C18 of the protochlorophyllide molecule, the process leading to the formation of an intermediate semi-reduced form similar to the mechanism of the stepwise reduction of the double bond described for the photoreaction of porphyrin reduction in solutions [49]. However, after it became clear that it was NADPH that served as an electron donor [50, 51], it was suggested that the sequential transfer of two electrons was rather unlikely due to the high energy of nicotinamide radicals [52]. Since the structure of the photoenzyme POR is similar to that of short-chain alcohol dehydrogenases, transfer of the hydride-ion from NADPH by a mechanism analogous to the mechanism of substrate reduction by alcohol dehydrogenases seemed to be a more likely option for the reaction of protochlorophyllide photoreduction. The reaction of protochlorophyllide photoreduction in the reaction mixture including protochlorophyllide, NADPH, and etioplast membranes was studied by NMR spectroscopy using NADPH isomers with radiolabeled hydrogen (3H). These studies showed that the hydride-ion from the 4S position in the nicotinamide nucleus of the NADPH molecule is transferred to position C17 of the protochlorophyllide molecule; the pigment molecule undergoes trans-reduction [53, 54]. The conservative amino acid residue Tyr193 of POR located near the bond C17=C18 is probably the source of the second proton [55-57]. According to the structural model of the POR enzyme [58], the D ring of the protochlorophyllide molecule is fixed against NADPH and the tyrosine residue to ensure the hydride-ion and proton transfer. POR was shown to lose its activity when the conservative amino acid residues Tyr193 and Lys197 were changed to Cys and Arg, respectively [55]. This constitutes a difference between POR and dehydrogenases, as such replacement is possible in the latter case. It was suggested that Tyr193 could be the donor of the second protein (Fig. 6). The proximity of Lys197 is necessary to reduce the pKa of Tyr193, which facilitates deprotonation of its phenol group [55]. Conservative residues Lys197 and Cys226 play an important role in the formation of the optimal structure of the ternary complex, providing the necessary steric conditions for the reaction of protochlorophyllide photoreduction [55-57, 59]. The proton from the tyrosine phenol group is transferred to the C18 atom of the protochlorophyllide molecule. In the case of the reconstructed ternary complexes with mutant POR where Tyr193 was replaced by Phe, the protochlorophyllide reduction stopped at the stage of the intermediate photoproduct and the second (light-independent) reaction stage was inactivated [56]. These data indicate that the hydride-ion is transferred first, before the proton transfer. The existence of several short-lived intermediates also supports the suggestion of non-simultaneous transfer of hydride-ion and proton during the photoreduction of the protochlorophyllide molecule.
Fig. 6. Hypothetical model of the mechanism of protochlorophyllide photoreduction by protochlorophyllide oxidoreductase in the active center of the ternary complex Pchld–POR–NADPH [55].
Paramagnetism of the molecules of electron donor or acceptor, which is manifested in the appearance of the light-induced ESR signal, is one of the most convincing evidences of the formation of charge transfer complexes (CTC) in a donor–acceptor system [60]. The formation of the charge transfer complex is accompanied by the appearance of a new absorption band when the redox potentials of the reaction partners are sufficient for the complete electron transfer from one molecule of the complex to the other [60]. However, if the difference in redox potentials of the molecule partners in the main state is rather small and insufficient for the complete electron transfer from the donor molecule to the acceptor molecule, a complex with partial charge transfer is formed. This is accompanied by fluorescence quenching, but the absorption spectrum remains unchanged without the appearance of new bands [60]. The assumption that protochlorophyllide photoreduction in vivo involves the stage of formation of a charge transfer complex has been expressed in a number of studies [8, 15, 20, 21, 30, 31, 61]. Based on the spectral characteristics of two non-fluorescent intermediates in vivo (R and X690 according to [11, 18, 19, 21]; X1 and X2 according to [26]), we can assume that their photoinduced formation corresponds to the formation of the complexes with partial [Dδ+ Aδ–] and complete [D+ A–] charge transfer [20, 21, 31]:
Raskin and Schwartz analyzing work [26] suggested that the rather long lifetime of the intermediate X1 (35-250 ns) indicates the existence of two intermediates at this stage: singlet exciplex and triplet exciplex of protochlorophyllide and hydrogen donor. The results of the studies of low-temperature phosphorescence spectra of whole etiolated leaves illuminated at 77 K also favor the formation of not only singlet, but also triplet exciplexes of protochlorophyllide and hydrogen donor, since under these conditions phosphorescence quenching of the active protochlorophyllide form was observed simultaneously with its fluorescence quenching [62]; the quantum yield of phosphorescence prior to illumination was very high (about 50%) [43, 62]. However, we think that additional experiments are required to answer the question of the involvement of the protochlorophyllide molecule triplet state in its photoreduction.
Heyes et al. conducted a comparative study of the reaction of protochlorophyllide molecule reduction in ternary complexes at 180 K using absorption, ESR, ENDOR, and Stark spectroscopies to elucidate the mechanism of this reaction [47]. ESR spectra indicating the existence of two types of paramagnetic products were registered for illuminated samples. However, quantitative evaluations of the ESR spectra indicated that only about 5% of the pigment was transformed into free radicals during almost complete transformation of protochlorophyllide active form (estimated by the changes in absorption spectra). A wide Stark effect characteristic of the charge transfer corresponded to the formation of a non-fluorescent intermediate with an absorption band at 696 nm. Stark spectroscopy data indicated the existence of two components in the non-fluorescent intermediate. So it was suggested that a charge transfer complex is formed at the initial stage of the protochlorophyllide photoreduction reaction. Temperature dependences of intermediate formation and NADPH oxidation proved to be identical. Therefore, it was suggested that the formation of the non-fluorescent intermediate involves the hydride-ion transfer to create a charge transfer complex. It was suggested that photon absorption by a protochlorophyllide molecule leads to a temporary separation of charges in the double bond C17=C18, promoting ultra-rapid transfer of the hydride-ion from NADPH to the C17 atom of protochlorophyllide [47, 63]. The resulting charge transfer complex facilitates proton transfer to the C18 atom in the subsequent dark reaction.
The importance of flexibility and dynamics of the POR enzyme for its catalytic function was illustrated in the studies on protochlorophyllide photoreduction in reconstructed ternary complexes using femtosecond absorption spectroscopy in the visible and infrared regions [64]. The results of the measurements showed that the first photon absorption activates the enzyme; as a result a high quantum yield of the Int 675 intermediate is observed after the second photon absorption in the picosecond time range. The authors suggested that minor structural changes may be involved in the primary light-dependent stage. These changes are supposed to optimize the alignment of the position of the NADPH nicotinamide ring and the tyrosine residue relative to the protochlorophyllide D ring.
Comparison of the results of studies of the molecular mechanism of protochlorophyllide photoreduction in vivo and in various model systems suggests that the primary stages characterized by fluorescence quenching and paramagnetic product formation are identical for the whole etiolated leaves and for all the model systems, including the simplest ones – the low concentration solutions. However, a number of facts suggest that the mechanism of protochlorophyllide photoreduction in vivo is somewhat different from the reaction mechanism in the model systems. First, the active complex in leaves probably has a more complex structure than the ternary complex reconstructed in vitro out of the three main components: Pchld, NADPH, and POR. This is evidenced, in particular, by differences in spectral characteristics between the artificial and natural complexes. There are several spectrally different protochlorophyllide active forms in etiolated leaves; the main forms are Pchld643/639, Pchld655/650, and Pchld653/648, which are accumulated and transformed in very young leaves; there are also several minor long-wave forms participating in the processes of protochlorophyllide photoreduction (see review [1]). One or two protochlorophyllide forms are usually found in reconstructed active ternary complexes: Pchld633/630 (active only at room temperature) and Pchld644/641 (photoactive also at low temperatures). The mechanism of protochlorophyllide photoreduction in vivo is apparently more complex, as evidenced by the results of research on this process in whole etiolated leaves at low temperature [19, 23], as well as the results obtained by high time resolution spectroscopy at physiological temperatures [26], which showed the presence of multiple stages in the reaction of protochlorophyllide photoreduction, including two or three short-lived intermediates. Only one short-lived intermediate is found when studying the reaction of protochlorophyllide phototransformation in artificial ternary complexes.
There is evidence of the presence of flavins in the active pigment–protein complex of etiolated leaves and their possible involvement in the primary reactions of protochlorophyllide photoreduction [65-67]. The results of our research support this possibility: fluorescence at 520 nm characteristic of flavins decreases after the leaves are illuminated with white or red (>600 nm) light at 77 K, the process being reversible after the temperature is increased [67].
Redox reactions between nicotinamides and flavins proceed via hydride-ion transfer [52]; the single-electron mechanism of redox reactions is characteristic of many flavoenzymes.
In plant leaves flavins can serve as an intermediate in the reaction, receiving the hydride-ion from NADPH and giving the electron to the pigment molecule. In this case, the reaction can follow the mechanism of multi-stage transfer of two electrons and two protons to form a semi-reduced pigment molecule with one attached electron (intermediate semi-reduced form) at the first stage, similar to the reactions of porphyrin photoreduction in solution [49]. It is possible that two variants of the mechanism of hydrogen transfer from NADPH to protochlorophyllide can exist in whole etiolated leaves: hydride-ion transfer directly from NADPH to the C17 position in the protochlorophyllide molecule followed by proton connection and/or flavin-mediated electron transfer from NADPH to the pigment. It is also possible that the mechanisms of the primary reactions of spectrally different active protochlorophyllide forms vary.
The results of studies of protochlorophyllide photoreduction in whole living cells and in the closest model systems – artificial ternary complexes comprising protochlorophyllide, NADPH, and POR, provided deeper understanding of the mechanism of this reaction. Both in the whole etiolated leaves and in reconstructed complexes, photoreduction of the chlorophyll precursor proceeds via the formation of short-lived intermediates of free-radical nature; NADPH is the hydride-ion donor and a tyrosine residue of the POR enzyme is the donor of the second proton. The charge transfer complex is the primary product of the reaction of protochlorophyllide photoreduction. The stage of primary intermediate formation could be modeled also in simple systems, e.g. protochlorophyll(ide) solutions. However, as mentioned above, the photoprocess is more complex in living systems than in artificially created ternary active complexes. Furthermore, in leaves there are several parallel reactions of spectrally different forms of chlorophyll precursor that play an important role in the creation of the system of the pigment forms of the photosynthetic apparatus. We believe that further studies using whole functional cells and tissues are essential. This approach is particularly important for further understanding of the still understudied regulation of the final stage of chlorophyll biosynthesis.
1.Belyaeva, O. B., and Litvin, F. (2007) Biochemistry (Moscow), 72, 1458-1477.
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27.Heyes, D. J., Hunter, C. N., van Stokkum, I. H. M., Grondelle, R., and Groot, M. L. (2003) Nat. Struct. Biol., 10, 491-492.
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38.Krasnovsky, A. A., and Bystrova, M. I. (1974) Chlorophyll (Shlyk, A. A., ed.) [in Russian], Nauka i Tekhnika, Minsk, pp. 139-153.
39.Bystrova, M. I., Safronova, I. A., and Krasnovsky, A. A. (1983) Doklady AN SSSR, 270, 1227-11231.
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text:
Q: Using Maildrop with Ubuntu Due to a total burn up, literally, of my Mandriva machine yesterday I've decided to upgrade to a newer and better distro. I've installed Ubuntu 14.04 LTS and am slowly getting things back in shape again. I'm using IMAP with my local folders under Evolution. Prior to the crash I was using fetchmail and procmail.
For some reason procmail won't install which is too bad as it was working great for me. I've moved onto Maildrop, have it installed but I'm having problems finding examples of the /etc/maildroprc file.
I've reinstalled fetchmail and courier-imap and both seem to be running fine. Would anyone have any examples of what a maildroprc file should look like? All the sites I've looked at on-line just don't seem to help or else I just don't understand them

A: Preamble:
I have been using maildrop for many years now to filter my mail (as a drop-in replacement for procmail). My usage has been:
mutt --> msmtp --> GMail --> getmail --> maildrop --> mutt

My mail spool is a very traditional /var/spool/mail/andrew and my central mailbox delivery is to $HOME/mail/mailboxes. So a little different to your own setup!
Nevertheless I can give an edited version of my maildrop filter, which I have placed as $HOME/.mailfilter (whereas I see that you have chosen /etc/maildroprc).
Filter example:
Below is a modified version of my own mailfilter, as you have requested in your question, which has in its expanded form served me well for many years:
#-------------------------------------------#
#  maildrop filters for $HOME/.mailfilter   #
#-------------------------------------------#

# --> Some Variables... <--  #

DEFAULT=/var/spool/mail/andrew
MAILBOX="$HOME/mail/mailboxes"
SENDMAIL="/usr/bin/msmtp"
logfile "$HOME/.mailfilter.log"
VERBOSE=9

# --> Filter / deliver mailing lists...<-- #

if (/^List-Id:.*ffmpeg-user.ffmpeg.org>/)
    to $MAILBOX/ffmpeg

# --> Filter / deliver Forums email...<-- #

if (/^From:.*forum@linuxquestions.org>/)
    to $MAILBOX/linuxquestions

# --> Filter / deliver old friends... <-- #

if (/^From:.*an_old_friend@une.edu.au>/)
    to $MAILBOX/an_old_friend

# -->  Send a CC on receipt ...      <--  #

if (/^From:.*@iinet.net.au>/)
{
    cc"!another_address@gmail.com"
}

In conclusion:
This is the old school way of doing mail and I hope this example of a working mailfilter will assist you to get your own setup working and perhaps interest other AU users in trying out the old ways...


text:
Little league pitcher banned for being too good?
By: Allison Croghan
A Massachusetts Little League pitcher, Tanner Beebe, says he was banned for being "too good," according to MassLive.com. He's still allowed to play, he just can't pitch.
The league disagrees, saying that 12-year-olds are "too old" to pitch in their minor league. Tanner's dad says that rule hadn't been enforced for years, until his son started throwing fastballs at 60 miles per hour. It's Tanner's first year playing baseball.
Click here to read the full story, then share your thoughts on our Facebook page.


text:
Q: Power BI - If a date is between 2 dates using relationships I am trying to determine if a date is between 2 other dates that are is 2 different tables using
Power BI.
For simplicity, here is the model that I have :

TableB is the bridge table between TableA and TableC.
I have an inactive relationship between tableA and TableC.
I have tried the following logic to check if TableC.createdDate is between TableA.startDate and TableA.endDate :

*

*Create a calculated column in TableC, but I was not able to access columns in TableA

*Create a calculated column in TableB, but I was having blank results, which is not suppose to happen

A: Have you tried using USERELATIONSHIP to force your calculated column to use the inactive relationship to TableA? documentation link
So something like
CALCULATE(
  {{created date is >start and <end}},
  USERELATIONSHIP('TableA'[TableB_ID],'TableC'[TableB_ID]
)


The Jackson JS3Q Kelly Bird basses truly deliver thunderous tone with formidable looks based on Jackson's classic Kelly body style. The Kelly Bird JS3Q four-string bass features a 34" scale length, a lightweight poplar body with a quilt maple top, bolt-on maple neck with graphite reinforcement and scarf joint, and a 12"-16" compound radius bound Amaranth fingerboard with 21 jumbo frets and pearloid block inlays. Dual high-output Jackson humbucking bass pickups create earthshaking sound that can be tweaked and refined thanks to its two volume controls and three-band active EQ, while a Jackson high mass bridge provides solid stability, improved sustain and warmer tone.


text:
Is Wil Wheaton's Table Top just a reality show for board game geeks?
Ryan Neudorf Culture June 19, 2015 March 16, 2016 2 Minutes
Yesterday Wil Wheaton wrote a blog post (and corresponding reddit post) in which he apologized for "completely screwing up the rules" in at least half (10 out of 21) of the episode of Table Top Season 3. IMHO his apology is a text book example of how not to apologize. He spends the majority of the post singling out and publicly shaming a specific producer on the show – the "rules guy." The way he's handling this has made me lose a lot of respect for the guy, but Reddit thread covers that ground pretty well, that's not what this blog post is about…
By placing so much blame on this producer and taking very little responsibility himself, he has revealed a lot about how the show works and I'm beginning to think it's more reality show than documentary.
Ostensibly, Table Top is a show were Wil Wheaton plays his favourite board games with his friends. He presents each and every game with such passion, knowledge and excitement that it is not a much of a logical leap to assume that he's played the game a few time and is at least familiar with the basic rules. In fact, he'll often throw in a pro-tip, a specific strategy that he likes to employ during a certain point in the game or a funny antidote.
I no longer believe this to be the case. In light of his blog post, I now feel like Table Top is more like a reality show where Wil Wheaton the actor, plays the character of Wil Wheaton the board game geek.
If Table Top was authentic, if Wheaton was actually into the games, if he knew the rules; then he wouldn't be blaming a producer so heavily. Sure the gamers might make little mistakes here and there, but anyone familiar with the rules should be able to catch the bigger mistakes. If not on the first or second round, then maybe a few rounds in and definitely when reviewing the episode.
The fact that they employee an expert to review the rules really demonstrates the "show-ness" of the show. I don't think someone outside of the Hollywood film & television industry would even think to hire someone like this. They would rely on the combined expertise of the team.
Not only that, but throughout the series Wheaton really strongly presents himself as the expert. If this was actually the case, having another expert on the team should be completely redundant. But the huge amounts of blame levelled on this one producer implies an opposite and equally huge amount of distance between Wheaton, the games and the production process.
I would not be surprised if the games instruction consisted of hand-holding Wil and friends through game between takes. "Roll the dice, then draw a card and … action."
Phewf.
That said, I think the show is still a great introduction to the world of modern gaming. It's certainly much more accessible than something like The Dice Tower or Shut Up & Sit Down. But I don't think I'll be watching the series again…
Published June 19, 2015 March 16, 2016
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Streamlining presentations just became a lot easier with AxPyMOL, a plugin for Windows PowerPoint that enables presentation of 3-D molecular data without having to "tab out" of PowerPoint slides.
AxPyMOL allows users to easily embed PyMOL shows saved from actual PyMOL sessions directly into PowerPoint slides. During presentation, the PyMOL shows can be manipulated within PowerPoint to display structures using multiple vantage points and rendering schemes set up in advance. Users can simply advance through the saved scenes of a PyMOL show without ever exiting PowerPoint. Visit purchasing options to obtain a license.
Windows 32-bit or 64-bit 7, 8, 10; PowerPoint 2003, 2007, 2010, 2013, and 2016.


text:
Q: Docker image won't connect to MySQL Workbench I have trouble connecting MySql Workbench with my Symfony 4 project via Docker on Windows 10.
My containers are built correctly and I can access the other two.
I am getting my web page on http://localhost:8080/ properly, but it seems that MySQL container is connecting on 172.18.0.1
The error is following: MySQL error
And this on docker ps command. Docker Images
I set my enviroment variables in docker-compose.yml and .env files.
services:
  project_web:
      container_name: project_web
      build: ./scripts/provision/docker/nginx/
      depends_on:
        - "project_php"
      ports:
          - 8080:80
      volumes:
          - .:/var/www/html:cached
  project_php:
      container_name: project_php
      build: ./scripts/provision/docker/php-fpm/
      depends_on:
        - "project_mysql"
      expose:
          - 9000
      volumes:
          - .:/var/www/html:cached
  project_mysql:
      container_name: project_mysql
      image: mysql:5.7
      volumes:
          - ./scripts/provision/docker/mysql/data:/var/lib/mysql:cached
          - .:/var/www/html:cached
      ports:
          - 3307:3306
      environment:
         MYSQL_ALLOW_EMPTY_PASSWORD: yes
         MYSQL_DATABASE: project
         MYSQL_USER: root
         MYSQL_PASSWORD: null
         DATABASE_URL: 'mysql://root:@project_mysql:3306/project'

Also tried to change ip to localhost, no success.

A: I see you're on windows. Try connecting to 127.0.0.1:3306 from Workbench. localhost sometime isn't recognized on Docker for windows.


Ameriphobia is the irrational fear and/or hatred of America, Americans or their culture. Ameriphobia encompasses the belief that all or most Americans are stupid, fat, bad, racist, or generally inferior. It is viewed as a new form of racism whereby Americans, a diverse and multicultural group, not a race, are nevertheless constructed as a race. A set of negative assumptions are made of the entire group to the detriment of members of that group.
During the 1990s some sociologists and cultural analysts hypothesized that there was a shift in forms of prejudice from ones based on skin colour to ones based on notions of cultural superiority and otherness Others, however, disagree, and hold that modern forms of prejudice are not substantially different from similar forms of prejudice that have existed in many other places and times.
The term 'phobia' emphasizes the irrational aspect of the term, and differs in intent and content from the more common anti-Americanism, which as an 'ism' seems like an ideology. Proponents of the term Ameriphobia resist lumping the two terms together. This concept is a parallel or mirror of the current usage of Islamophobia and is meant to play a part in the debate about the US-Muslim relationship, recognizing the possibility of irrationality and 'racism' on both sides.
An Ameriphobe is someone who hates America. Ameriphobic is an adjective describing such a person or attitude. Ameriphobia is the general concept.
Critics charge that terms like Ameriphobia do not make sense because America is not a race but a mixture of peoples. This is countered however by the analysis about about the changing nature of prejudice. Scientists doubt also the existence of distinct human races, so such a criteria would seem obsolete.


Loaf of thin sliced sour dough bread.
1. Start briquettes in starter.
2. Mix Cream Cheese, 1/8c of powder sugar, and crushed walnuts into a bowl. Mix to taste.
3. Spread 1/4"of Cream cheese mix on one slice of bread. Add second slice to create sandwich.
4. Mix pint of whipping cream and eggs together. Stir in nutmeg and cinnamon.
5. Invert Dutch oven upside down. Place 6 – 8 evenly spaced briquettes under the lid.
6. Place lid smooth side up on the legs of the pot to use as a griddle.
7. Add a little oil to lid to keep French toast from sticking. Griddle should be ready when you put a couple of drops of water on it and it sizzles.
8. Dip the Cream cheese bread into the whipping cream/egg mixture and set on lid.
9. Cook to desired color. If the lid seems to hot, remove 2 briquettes at a time. Slow cooking is always desirable.
10. When ready, top with either Maple syrup, sprinkle powder sugar, or spread favorite jam. Enjoy!
Hints: Serves 8 – 10 depending on the loaf size.


text:
Urge your Congress members to join Rep. Sanchez and others in calling for justice for Alex Odeh
Please urge your congress members to take action to obtain justice for Alex Odeh now!
On October 11, 1985, Alex Odeh, ADC's Southern California Regional Director, was killed when a powerful pipe bomb exploded as he entered the ADC office in Santa Ana, California. Alex, a published poet, lecturer of Arabic Language and Middle East history at Coastline College in Santa Ana, and tireless peace activist, dedicated his life to the defense of civil liberties at home, and civil and human rights abroad. The bomb injured several other victims in addition to killing Alex.
Last November, key members of Congress took action to obtain justice for Alex Odeh, by petitioning the House Judiciary Committee to hold a hearing and the Department of Justice to provide information on the FBI investigation.
Congresswoman Loretta Sanchez and Congressman John Conyers, a ranking member of the House Judiciary Committee, wrote a letter to the Chairman of the U.S. House Judiciary Committee, Bob Goodlatte. The letter requested a hearing to address the unresolved case of Alex Odeh's murder. The House Judiciary Committee previously held a hearing on the Odeh case in 1986, but has not had a hearing since. The case remains unresolved despite the fact that the FBI called the bombing an act of terrorism and designated an investigation into the bombing as a highest national priority. Thus, the Sanchez and Conyers letter called for a new hearing to find out why justice has been delayed for so long and to finally bring resolution to the case.
Congresswoman Sanchez also sent a letter to Attorney General Eric Holder on November 6, 2013. The letter was jointly signed by Congresswoman Sanchez, Congressman Jim Moran, Congressman Keith Ellison, and Congresswoman Eleanor Holmes Norton.
The FBI's investigation into Alex's murder remains open. There is a reward of up to $1 million for information leading to an arrest and conviction. Yet, no arrests have been made–in spite of the fact that the FBI identified members of the Jewish Defense League (JDL) as suspects shortly after the attack.
ADC and the Arab American community are deeply troubled that, despite all the available leads to resolving Alex's murder, the perpetrators have been at large for nearly three decades. ADC continues to seek support for a Congressional Hearing on the Alex Odeh case as well as greater support from the Department of Justice in investigating the case. As Congresswoman Sanchez said, "I hope the Chairman and the Department of Justice will heed our calls, stop this delay of justice and help the Odeh family find closure."
Take a stand for Justice Now: Ask your congressional members to call on the House Judiciary Committee to hold new hearings on the issue.