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REVIEW: Spectral and Kinetic Parameters of Phosphorescence of Triplet Chlorophyll a in the Photosynthetic Apparatus of Plants
A. A. Krasnovsky, Jr.1,2* and Yu. V. Kovalev2
1Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky pr. 33, 119071 Moscow, Russia; fax: (495) 954-2732
2Lomonosov Moscow State University, 119899 Moscow, Russia; E-mail: phoal@mail.ru
Spectral and kinetic parameters and quantum yield of IR phosphorescence accompanying radiative deactivation of the chlorophyll a (Chl a) triplet state were compared in pigment solutions, greening and mature plant leaves, isolated chloroplasts, and thalluses of macrophytic marine algae. On the early stages of greening just after the Shibata shift, phosphorescence is determined by the bulk Chl a molecules. According to phosphorescence measurement, the quantum yield of triplet state formation is not less than 25%. Further greening leads to a strong decrease in the phosphorescence yield. In mature leaves developing under normal irradiation conditions, the phosphorescence yield declined 1000-fold. This parameter is stable in leaves of different plant species. Three spectral forms of phosphorescence-emitting chlorophyll were revealed in the mature photosynthetic apparatus with the main emission maxima at 955, 975, and 995 nm and lifetimes ~1.9, ~1.5, and 1.1-1.3 ms. In the excitation spectra of chlorophyll phosphorescence measured in thalluses of macrophytic green and red algae, the absorption bands of Chl a and accessory pigments – carotenoids, Chl b, and phycobilins – were observed. These data suggest that phosphorescence is emitted by triplet chlorophyll molecules that are not quenched by carotenoids and correspond to short wavelength forms of Chl a coupled to the normal light harvesting pigment complex. The concentration of the phosphorescence-emitting chlorophyll molecules in chloroplasts and the contribution of these molecules to chlorophyll fluorescence were estimated. Spectral and kinetic parameters of the phosphorescence corresponding to the long wavelength fluorescence band at 737 nm were evaluated. The data indicate that phosphorescence provides unique information on the photophysics of pigment molecules, molecular organization of the photosynthetic apparatus, and mechanisms and efficiency of photodynamic stress in plants.
KEY WORDS: chlorophyll, triplet state, phosphorescence, photodymanic stress, photosynthesis
DOI: 10.1134/S000629791404004X
A concept stating that the metastable state of dyes, which is responsible for dye phosphorescence, is a triplet was advanced by A. N. Terenin in 1943 [1] and independently by G. Lewis and M. Kasha in 1944 [2]. Initially this concept met strong resistance from the school of J. Frank. Later it was proved in papers of many authors, and 10 years later it was also accepted by Frank and his followers [3]. Acceptance of this concept caused reconsideration of the well-known Jablonski scheme [4], which after these papers was considered as evidence for the existence of singlet and triplet excited states of dyes. Direct radiative deactivation of the singlet state is accompanied by short-lived fluorescence with a lifetime in the nanosecond time range. Direct radiative deactivation of the triplet state causes millisecond phosphorescence (Fig. 1). Another important consequence of this concept was the acceptance of the fact that emission of fluorescence and phosphorescence is a basic photophysical property of dye molecules.
Fig. 1. Simplified Jablonski diagram. 1Dye0, 1Dye*, and 3Dye* are dye molecules in the ground and excited singlet and triplet states.
It is natural that soon after these papers the question arose whether this scheme could be applied to chlorophyll, whose phosphorescence had not been discovered at that time. This question was clearly formulated for the first time by A. N. Terenin and A. A. Krasnovsky (my father) at the 1st All-Union Conference on Photosynthesis in 1946 (Moscow) [5, 6], who claimed also that knowledge of the roles of the triplet and singlet states in photosynthesis is one of the major problems of the mechanism of this process.
As measurement of phosphorescence was at that time the only way to detect triplet states, attempts to observe the phosphorescence of chlorophylls (Chl) a and b were repeatedly made by scientists from recognized research laboratories during 1948-1969. However, reliable data were not obtained [7-15]. In particular, the first papers that reported the registration of Chl a phosphorescence in frozen (77 K) solutions using a photographic technique were from Becker's group [12, 14] (Table 1). In the nonpolar solvent 3-methylpentane, they observed luminescence of Chl a with a maximum at 755 nm and quantum yield of about 10%, which was proposed to be n-π phosphorescence of the pigment [12]. In the solvent mixture EPA (diethyl ether–ethanol–pentane 5 : 3 : 5 v/v), which forms a transparent glass at 77 K, they observed phosphorescence of Chl a with maxima at 885 and 925 nm. The luminescence lifetime was estimated to be ≥0.5 ms, and the quantum yield was about 50 times less that the quantum yield of fluorescence [14]. In 1969, Amster repeated these measurements using a mechanical phosphoroscope and photographic plates of a new generation [15]. He could not detect chlorophyll afterglow with the quantum yield indicated in published papers [12, 14]. According to Amster, in both 3-methylpentane and a mixture of ether and 3-methylpentane, the phosphorescence was several orders of magnitude weaker, though an accurate value of the quantum yield was not reported. In both solvents, the maximum of phosphorescence of Chl b was found at 865 nm. The maxima of the Chl a phosphorescence were found at 800 and 840 nm. Using a phosphoroscope, Amster did not observe afterglow in the region 730-760 nm. However, this emission was detected in 3-methylpentane if measurements were performed without the phosphoroscope. Therefore, he attributed it to fluorescence of chlorophyll aggregates of higher order than chlorophyll dimers [15].
Table 1. Results of the first reported measurement of Chl a phosphorescence
Note: φph/φf is the ratio of the quantum yields of phosphorescence and fluorescence.
The first reliable measurements of chlorophyll phosphorescence in frozen solutions were carried out by our group in papers of 1971-1975 using setups with mechanical phosphoroscopes [16-20]. In the first paper of this series (1971), IR phosphorescence of 4-vinylprotochlorophyll and 4-vinylprotopheophytin was discovered, which had never been studied before [16]. Photomultipliers with S-11 spectral response were used as detectors, which are sensitive in the infrared up to 900 nm. Ethanol was used as the solvent. In these experiments, phosphorescence was detected that corresponds to the shortest-wavelength form of protochlorophyll present in the ethanol solutions. The emission maximum was observed at 870-880 nm, the lifetime was 4-5 ms, and the quantum yield was about 10–5 [16].
For further measurements, setups were constructed whose sensitivity in the infrared was increased by 2-4 orders of magnitude. Cooled photomultipliers FEU-83 (S-1) sensitive in the 400-1300 nm range, powerful (1 kW) xenon lamps, and high-throughput grating monochromators were used. Technical parameters of the phosphoroscopes were greatly changed. Detailed description of these setups was presented in papers [21-27]. The new instruments allowed measurement of spectra and lifetimes of IR phosphorescence at 700-1300 nm with quantum yield ≥10–9-10–10 and lifetimes ≥0.5 ms.
The use of these setups allowed us to reliably detect phosphorescence of Chls a and b and their magnesium-free analogs. More accurate data on protochlorophyll phosphorescence were also obtained [16-20]. It was found that the parameters of phosphorescence of Chl a are quite different from those described in the papers cited above (Table 1). In both polar and nonpolar solvents, the maxima of Chl a phosphorescence were observed at λ > 920 nm. The emission at 755 nm in the nonpolar solvent pentane was shown to be fluorescence of aggregated chlorophyll, as Amster also claimed [15]. Three spectral forms of chlorophyll phosphorescence – monomers Mg-monosolvates (Mg-L), monomers Mg-disolvates (Mg-L2), and aggregates (dimers and oligomers, Chln) – were also observed. It was also the first experimental observation of the triplets of these forms [18-20].
Apparently, the results of our phosphorescence studies actually disproved the experiments of well-known groups. In 1977-1979, our data were confirmed by other authors (Table 2). As a result of these studies, researchers obtained a new method of spectral analysis that allows precise measurement of energy and lifetimes of triplets and analysis of interaction of the pigments with environment.
Table 2. Parameters of phosphorescence of chlorophylls and pheophytins reported in papers of different groups
* EPA (mixture of diethyl ether, pentane and ethanol) as solvent.
** Mixture of diethyl ether and petroleum ether (1 : 1) as solvent.
*** Methyltetrahydrofuran as solvent.
In addition in 1975, phosphorescence of chlorophyll and protochlorophyll was observed in etiolated plant leaves. Also, phosphorescence was discovered in solutions of Chlorobium chlorophylls and their magnesium-free analogs [19, 20]. The results of these studies were outlined in papers [33-36].
In 1978-1981, the authors of the present review discovered and investigated phosphorescence of Chl a in mature leaves and chloroplasts of normal and mutant plants, in cells of green, red and brown algae, and in suspensions of cyanobacteria at 77 K [37-41]. Since that time many data have been accumulated (see reviews [27, 42-45]). Nonetheless, this information is poorly known. Moreover, a certain part of experimental materials dealing with mature leaves and chloroplasts was described only in dissertation works of these authors. Objectives of this mini review consist in introduction of certain unpublished data of the authors and in reconsideration of experimental information on the spectral and kinetic parameters and quantum yields of chlorophyll phosphorescence in chloroplasts of green plants and algae.
Chlorophyll a in solutions and model systems. For analysis of the photosynthetic systems one should shortly describe modern views on phosphorescence of chlorophyll in solutions and model systems. Detailed discussion is presented in a recent review [27]. Investigation of phosphorescence in chlorophyll solutions is complicated by the fact that upon freezing to 77 K chlorophyll often forms several spectral species whose concentrations depend on the concentration of the pigments and also on nature and state of solvents. Approximate parameters of these forms obtained by our group and other researchers are summarized in Table 3. It is of interest that the spectral properties of phosphorescence are more sensitive to solvation and aggregation of chlorophyll than the parameters of the absorption and fluorescence spectra. For instance, as Table 3 shows, maxima of the absorption spectra of Mg-L2 and maxima of the excitation spectra of Mg-L2 phosphorescence are shifted by 12-14 nm to longer wavelengths compared to Mg-L, whereas the phosphorescence spectra of Mg-L2 are shifted by 40-50 nm compared to Mg-L.
Table 3. Parameters of phosphorescence of Chl a in different states of solvation and aggregation [22, 27, 33-35, 42-49]
Note: λex denotes the main red maximum of the excitation spectrum; λph denotes the maxima of the phosphorescence spectra. (Mg-0) is a chlorophyll molecule with nonsolvated magnesium atom; τph is the lifetime corresponding to the main phosphorescence maximum.
For comparison with the photosynthetic apparatus, it is convenient to use systems in which only one chlorophyll species dominates. Such systems are diluted (1-3 µM) solutions of chlorophyll in pyridine and diethyl ether frozen as snow, in which monomeric Mg-L2 or Mg-L chlorophyll molecules dominate [27, 46, 47]. Heterogeneous aqueous suspensions containing Chl a solubilized by micelles of the detergent Triton X-100 and chlorophyll-containing suspensions of liposomes are different examples of such systems. In these systems, pentacoordinate (Mg-L) monomeric molecules of chlorophyll are formed whose phytol tail is located in the hydrophobic phase of the micelles and the magnesium atom is connected with the hydrophilic polar groups of detergents or lipids [27, 46, 47].
Spectra of phosphorescence and fluorescence of Chl a in pyridine and detergent micelles at 77 K are shown in Fig. 2. Each spectrum has two bands. The energy gap between the maxima of these bands is equal to 1250 ± 50 cm–1 in both systems. Thus, the spectra of radiative deactivation of both the singlet and triplet states have similar vibronic structure.
Fig. 2. Phosphorescence (1) and fluorescence (2) spectra of Chl a solutions (3-5 µM) at 77 K: a) in aqueous micellar solutions of detergent Triton X-100; b) in pyridine. Phosphorescence was measured under excitation by red light λ ≥ 620 nm; the monochromator slits corresponded to 6 nm. Fluorescence was excited by monochromatic light corresponding to the maximum of the Soret band; the monochromator slits corresponded to 2 nm (data of papers [20, 27, 46, 47]). Numbers over the curves show wavelengths of maxima in nanometers.
The bandwidth (FWHM) of the main phosphorescence bands in both pyridine and detergent micelles was 55 ± 2 nm (~620 cm–1). This is much greater than the bandwidth of the main fluorescence band (19 ± 2 nm, ~450 cm–1). The energy of the chlorophyll triplet state in pyridine and detergent (calculated from the maxima of the phosphorescence spectra) corresponds to 1.3 ± 0.03 eV. The energy of singlet–triplet splitting is 0.56 eV in pyridine and 0.51 eV in detergent micelles (~4500 cm–1). The spectra of chlorophyll phosphorescence are rather similar in diethyl ether and detergent micelles (Table 4). In solvent mixtures forming a glass at 77 K (for instance EPA or a mixture of diethyl and petroleum ethers, 1 : 1) the phosphorescence spectra are close to the phosphorescence spectra of the Mg-L2 in pyridine [18, 27, 29-31, 46, 47].
According to the data of several groups, the quantum yield of Chl a phosphorescence (φph) is (2 ± 1)·10–5 [17-20, 28, 30]. It should be noted that φph is determined by the following equation:
φph = φst × kr × τph, (1)
where φst is the quantum yield of the triplet state population, kr is the rate constant of radiative deactivation of the triplet state, and τph is the phosphorescence lifetime. Hence:
φst × kr = φph/τph. (2)
Table 4 summarizes relative quantum yields of chlorophyll phosphorescence in different media. One can see that in pyridine and diethyl ether the quantum yields (φph) are rather similar (the difference does not exceed ±10%). The ratio φph/τph in detergent micelles, pyridine, and diethyl ether are also almost equal within the precision of our measurements.
According to flash photolysis data, φst ~ 0.6 for monomeric chlorophyll molecules. The degree of solvation of the central magnesium atom changed φst by not more than by 10% [50]. A similar result was also obtained upon measurement of the quantum yields of singlet oxygen generation by Mg-L- and Mg-L2-solvates of chlorophyll [51]. Hence using Eq. (2), one can conclude that the rate constant of radiative deactivation of the triplet chlorophyll molecules (kr) almost does not depend on the degree of solvation of the central magnesium atom.
At the same time, as Table 4 shows, solvation of the magnesium atom does not change also the fluorescence quantum yield (φf) and the ratio φph/(τphφf). Similar values of these parameters were obtained in other model systems in which chlorophyll molecules are monomeric, as for instance, chlorophyll-containing liposomes [27, 46, 47].
Thus, parameters of φph, φph/τph and φph/(τphφf) have rather constant values for monomeric chlorophyll molecules solvated only by the central magnesium atom (Mg-L and Mg-L2). Deviation from these values indicates a change in a state of pigment molecules in the systems under investigation.
For instance, these parameters are markedly reduced in solutions of chlorophyll in ethanol (Table 4), which were used for a long time as a reference in our measurements of the quantum yields of chlorophyll phosphorescence in the photosynthetic systems [38]. It is likely that the phosphorescence of Chl a in frozen ethanol solutions mostly correspond to Mg-L2 solvates, whose C=O group of the V-ring is simultaneously hydrogen bonded by ethanol. Detailed discussion of this type of solvation is given in papers [22, 27]. According to our data, strong decrease in all parameters – φph, φph/τph, and φph/(τphφf) – is observed upon aggregation of chlorophyll molecules [18-20, 27].
It should be noted that chlorophyll phosphorescence is always accompanied by low temperature delayed fluorescence (Fig. 3). Under conditions of the experiments illustrated by Fig. 3, delayed fluorescence was 300 times weaker than phosphorescence in detergent solutions and 15 times weaker than phosphorescence in pyridine. In both cases, the intensity of delayed fluorescence is proportional to the square of the intensity of the exciting light. The lifetime of phosphorescence was around 2 ms. Stronger delayed fluorescence was observed in chlorophyll-containing liposomes [27, 42, 46, 47]. The data indicate that low temperature delayed fluorescence accompanies a recombination process whose efficiency strongly depends on solvents and chlorophyll concentration. It seems improbable that triplet–triplet annihilation might occur in rigid solutions with low, micromolar chlorophyll concentrations. An assumption was proposed that afterglow arises as a result of interaction of triplet chlorophyll molecules with a metastable photoproduct that appears as a result of reaction of triplets with solvent molecules [42].
Greening etiolated leaves. The first measurements of phosphorescence of protochlorophyll and chlorophyllide in frozen etiolated and greening leaves were reported by our group in 1975 [19, 20]. To the best of our knowledge, these data were the first experimental evidence of population of pigment triplet states in the developing photosynthetic apparatus of green plants.
It is known that protochlorophyllide is the major pigment of etiolated leaves ([52, 53] and references therein). Spectral and kinetic parameters of protochlorophyllide phosphorescence were many times reported in papers of our lab [20, 27, 33-35, 54-56]. Upon illumination of etiolated leaves, photoreduction of protochlorophyllide occurred followed by chlorophyll accumulation. After 1 h of greening (just after the Shibata shift) the major pigment is Chl a ([52, 53] and references therein). In our experiments, etiolated seedlings of bean, pea, and wheat were studied. In all these seedlings, after 1 h greening Chl a was formed with absorption and fluorescence maxima at 670-672 and 682-684 nm, respectively.
Simultaneously, at 77 K chlorophyll phosphorescence was observed with the main maximum at 955 ± 5 nm and the vibrational satellite at 1100 nm (Fig. 3). The lifetime in the main maximum was 1.8-2 ms. The bandwidth (FWHM) of the major bands of fluorescence and phosphorescence spectra were about 20 and 55 nm. Thus, the spectral parameters of chlorophyll phosphorescence in greening leaves resemble those in micelles of detergent and pyridine.
Table 4. Quantum yields (φph) and lifetimes (τph) of phosphorescence of Chl a in different solvents at 77 K according to the data our group [22, 27, 38, 42, 46, 47, 57]
* The absolute quantum yield in pyridine and ether is (2 ± 1)·10–5; the fluorescence yield at 77 K is 55-60% [30].
Fig. 3. Low temperature (77 K) phosphorescence spectra (1) and fluorescence spectra (2) of Chl a in etiolated bean leaves after 1 h of greening; 3) the absorption spectrum of the leaf at 77 K; 4) phosphorescence excitation spectrum upon registration of light emission at λ ≥ 900 nm. L/I is the ratio of the phosphorescence intensity to the intensity of excitation; 1–T is the fractional absorbance of a leaf [20, 27, 33-35, 57].
On the other hand, the maximum of the phosphorescence spectrum in greening leaves is shifted to longer wavelengths compared to the Mg-L solvates in solutions, and to shorter wavelengths compared to the Mg-L2 solvates (compare the data of Table 3 and Figs. 2 and 3). The phosphorescence lifetime of chlorophyll in greening leaves is also markedly less than that of the Mg-L species in solutions. Thus, we can conclude that according to the spectral and temporal parameters, phosphorescence of Chl a in leaves on the early stage of greening does not correspond to phosphorescence Mg-L or Mg-L2 species of monomeric chlorophylls.
Comparison of the data presented in Tables 3 and 4 leads to an assumption that chlorophyll phosphorescence in greening leaves belongs to short wavelength aggregates (probably dimers) of chlorophyll. In agreement with this assumption, φph and the parameters φph/τph and φph/(φfτph) are about two times less in greening leaves than in solutions of monomeric chlorophyll molecules (Table 4). As mentioned above, the quantum yield of the triplets in solutions of monomeric chlorophyll is about ~0.6 [30, 50]. If one takes into account Eq. (2) and proposes that the rate constants of radiative deactivation of chlorophyll triplets (kr) are equal in greening leaves and solutions, one can conclude that the quantum yield of the Chl a triplet state (φst) in greening leaves is about 0.25 [22, 27, 42, 54, 57]. This value can be regarded as the lower limit of φst, because it is not excluded that kr might be smaller in greening leaves than in solutions.
In both chlorophyll solutions and greening leaves, phosphorescence was accompanied by low temperature delayed fluorescence. The relative intensity of delayed fluorescence in leaves was greater than in solutions (Fig. 3). The intensity of delayed fluorescence was proportional to the square of the intensity of excitation.
The maximum of the excitation spectrum of chlorophyll phosphorescence in greening leaves was observed at 670 nm. Hence, it is located closely to the absorption maximum of chlorophyll (Fig. 3). As Fig. 3 shows, the excitation spectrum does not have the bands of carotenoids at 400-500 nm, though the bands of carotenoids dominate in the absorption spectra of leaves.
Thus, the data indicate that in agreement with Butler's data [58], there is no energy transfer from the singlet states of carotenoids to chlorophyll at this stage of development of the photosynthetic apparatus. Also, as seen from Table 4, the lifetime of phosphorescence is about 2 ms. Hence, there is no energy transfer from the triplet state of Chl a to carotenoids [20, 33-35, 54, 57].
Phosphorescence of chlorophyll in mature plant leaves. Further development of the photosynthetic apparatus led to a sharp decrease of the phosphorescence yield, though the phosphorescence lifetime was almost unchanged [20, 22, 24, 42, 54, 57]. Table 5 illustrates the dependence of the phosphorescence yield on time of greening of etiolated seedlings of wheat. During greening the main maximum of the phosphorescence spectrum was shifted from 953 to 980 nm. After 48 h of greening, the phosphorescence yield reached the minimum value, about 2000 times smaller than the quantum yield of phosphorescence of monomeric chlorophyll in solutions (Table 5). Further "greening" did not change the phosphorescence yield. Similar data were obtained upon greening of etiolated leaves of pea, bean, and barley.
Table 5. Changes in intensity of Chl a phosphorescence in etiolated wheat leaves during greening*
* Phosphorescence was measured at 77 K under excitation by a xenon lamp through a KS-15 cut-off filter (λ ≥ 640 nm). Greening was observed under white light of 1000 lx (Kovalev and Krasnovsky, unpublished data).
Because of the very low yield of chlorophyll phosphorescence in mature leaves, reliable detection of this light emission was a difficult problem whose solution required from us much effort. The first measurement of chlorophyll phosphorescence in mature leaves and suspensions of cells of green, brown, and red algae and cyanobacteria was reported by us in 1978 [37]. Later these measurements were many times repeated by our group using different photosynthetic organisms.
Figure 4 shows the spectrum of chlorophyll phosphorescence in a mature pea leave. One can see that upon excitation by red light through the cut-off red filter transmitting light at λ ≥ 650 nm, the main phosphorescence maximum was observed at ~980 nm. The phosphorescence spectrum has also a long-wavelength satellite at ~1100 nm, whose intensity was about two times less. The phosphorescence lifetime was ~1.7 ms. Upon excitation by dark red light, the main phosphorescence maximum was shifted to 990 nm, and the lifetime decreased to ~1.3 ms. Thus, phosphorescence is emitted by at least two spectral forms of chlorophyll. Judging by the fact that the phosphorescence lifetime is millisecond, the triplet states of these forms are not quenched by carotenoids.
Fig. 4. Spectra of delayed luminescence (1, 2) and fluorescence (3) of chlorophyll in mature pea leaves at 77 K. Spectra 1 and 2 were recorded under excitation by red light λ ≥ 640 nm (1) and far red light λ ≥ 680 nm (2). Monochromator slit width was 20 nm. The spectrum of fluorescence (3) was recorded upon excitation by 440 nm monochromatic light. The width of the monochromator slit was 2 nm. Absorbance of the leaf in the red absorption maximum was ~2.
Figure 5 shows the major band of the phosphorescence spectrum in a suspension of pea chloroplasts. The absorbance in the maximum of the absorption band of this sample was 0.8 at 77 K, being much smaller than in mature leaves. Under excitation by red light transmitted by a KS-17 cut-off filter (λ ≥ 650 nm), the maximum of the phosphorescence spectrum was observed at 960 nm. The lifetime was 2 ms. Under excitation by dark red light (λ ≥ 680 nm), the maximum was shifted to 975 nm. The lifetime decreased to 1.4 ms [38-41]. The band at 990 nm was observed only in dense chloroplast suspensions whose absorbance was close to that of mature leaves.
Fig. 5. Spectra of fluorescence (1) and phosphorescence (3, 4) of chlorophyll in suspensions of pea chloroplasts at 77 K. Fluorescence was excited by 440 nm blue light, phosphorescence was excited through cut-off red filters KS-17 (λ ≥ 650 nm) (1) and KS-18 (λ ≥ 680 nm) (2). Upon fluorescence measurement, the absorbance in the red absorption maximum of suspensions was 0.05, and the slit width was 1 nm. Upon measurement of phosphorescence the absorbance was 1, and the slit width was 20 nm. Data of reference [39] and further unpublished experiments of the authors.
IR phosphorescence of chlorophyll was always accompanied by delayed fluorescence whose major spectral maximum coincided with the maximum of the low temperature chlorophyll fluorescence (735-740 nm) (Fig. 4). In green leaves, the relative intensity of delayed fluorescence was much higher than in chlorophyll solutions and greening leaves. It was shown that the main maximum of the excitation spectrum of delayed fluorescence was observed at 350 nm, i.e. it does not belong to chlorophyll [37, 38, 40-42, 59]. The nature of this phenomenon deserves a special discussion that is out of the scope of this review.
Millisecond phosphorescence and delayed fluorescence of chlorophyll with the same spectral and temporal parameters was detected in mature leaves of all plants we investigated (maize, barley, pea, birch, maple, rowan-tree, and others). The quantum yield of chlorophyll phosphorescence in plant leaves grown under natural conditions, which were taken for analysis in daytime, was always 1000 times less than in greening leaves after 1 h of greening and 2000 times less than in solutions of monomeric chlorophyll. Chlorophyll phosphorescence in suspensions of the class B chloroplasts was usually three times stronger than in mature leaves [39].
Thus, the quantum yield of chlorophyll phosphorescence in mature leaves and chloroplasts of green plants grown under normal conditions is ~10–8 [38-42, 44, 45, 57]. As so strong decrease in the phosphorescence yield is not accompanied by the decrease in the phosphorescence lifetime, we conclude that phosphorescence is emitted by a minor part of the chlorophyll molecules spatially separated from carotenoids of the photosynthetic apparatus. In this case, the quantum yield of chlorophyll phosphorescence in leaves can be described by the following equation:
φph = kr × φst × τph × αchl, (3)
where αchl is a molar fraction of phosphorescence-emitting chlorophyll relative to the entire chlorophyll concentration. It is most likely that the product kr × φst × τph has the same value in both etiolated leaves after 1 h of greening and in mature leaves. This leads to the φph ratio for phosphorescence in mature leaves compared to greening leaves after 1 h of greening ((φph)mature/(φph)etiol) equal to 0.1%. Hence, only 0.1% of the overall chlorophyll is involved in phosphorescence emission in leaves. In isolated chloroplasts this value is about 0.3%, as mentioned above.
It was observed that the intensity of chlorophyll phosphorescence in leaves strongly depended on external factors. For instance, phosphorescence increased 3-fold if plants were grown under low illumination (less than 50 lx). Phosphorescence intensity increased under any actions that damaged the chloroplast structure. For instance, after heating, the action of organic solvents, detergents, and herbicides, and also in mutant plants. Especially strong increase of phosphorescence intensity was observed after inhibition of biosynthesis of carotenoids or change of carotenoid composition [38, 40, 41].
It should be noted that mature leaves and chloroplasts cannot be used for reliable measurement of the excitation spectra of chlorophyll phosphorescence. Such measurements were hampered by the high absorbance of leaves and by strong delayed fluorescence, the long wavelength tail of which overlaps with the phosphorescence bands of chlorophyll. Such overlapping is especially strong under excitation by green or blue light. Rough estimate has shown that the red maximum (~670 nm) of the excitation spectrum of chlorophyll phosphorescence in leaves and chloroplasts is shifted to shorter wavelengths compared to the red absorption maximum (676 nm) [39].
Macrophytic algae. Transparent thalluses of macrophytic algae are much more convenient for spectral measurements. Absorbance of thalluses did not exceed 0.7. The spectra of phosphorescence emission are shown in Fig. 6. Under excitation by red light the emission band at 955 nm dominated, which resembles the band of chlorophyll phosphorescence in etiolated leaves after 1 h of greening. The lifetime corresponding to this band was 2.0 ± 0.2 ms. Under excitation by far red light, the maxima were shifted to 972 ± 4 nm (Fig. 6). The lifetime decreased to 1.3 ± 0.2 ms [60]. Low temperature delayed fluorescence of chlorophyll in these algae was much weaker than in leaves.
Fig. 6. Spectra of chlorophyll phosphorescence in thalluses of macrophytic algae: green Ulva fenestrata (1, 2), brown Sargassum pallidum (3, 4), and red Grateloupia turuturu (5, 6) under excitation via the cut-off light filters KS-15 (λ ≥ 640 nm) (1, 3, 5) and KS-18 (λ ≥ 680 nm) (2, 4, 6) at 77 K. The width of monochromator slits was 15 nm. Data of reference [60].
The combination of favorable properties, transparent thalluses with relatively low absorbance of chlorophyll and relatively low intensity of delayed fluorescence, allowed us to measure the excitation spectrum of chlorophyll phosphorescence in the visible region (Fig. 7). Figure 7 shows that in green algae the main maxima of excitation spectra (438 and 674 nm) correspond to Chl a. The excitation spectrum also has the distinct maxima of Chl b (650 and 470 nm) and carotenoids (490-500 nm). In the excitation spectrum of chlorophyll phosphorescence in red algae, the maxima of chlorophyll (674 nm) and maxima of phycobilins are clearly seen (Fig. 7). It is noteworthy that the red (chlorophyll) excitation maximum is slightly shifted to shorter wavelengths compared to the main absorption maximum of chlorophyll (678 nm) [60].
Fig. 7. Excitation spectrum of chlorophyll phosphorescence in thalluses of green algae Ulva fenestrate (a) and red algae Grateloupia turuturu (b) at 77 K. Phosphorescence was measured through an IR cut-off filter transmitting light at λ ≥ 900 nm. The ratio of the fluorescence intensity and the intensity of exciting light is indicated on the Y axis in relative units. The monochromator slit width was 7 nm. Data of reference [60].
These data suggest that phosphorescence is emitted mostly by the short wavelength chlorophyll forms, which are connected with the light harvesting complex containing accessory pigments (Chl b, carotenoids and phycobilins). Therefore, one can assume that the chlorophyll molecules responsible for emission of millisecond phosphorescence are a part of the natural pigment protein complex of chloroplasts. As phosphorescence-emitting chlorophyll molecules can also fluorescence, it was of interest to estimate a contribution of this fluorescence to the overall chlorophyll fluorescence in chloroplasts.
Comparison of phosphorescence and fluorescence of chlorophyll in chloroplasts. For these studies, suspensions of isolated chloroplasts were used. It is known that at 77 K the main maximum of chlorophyll fluorescence in chloroplasts is observed at 737 nm (Fig. 5). At the same time, the fluorescence spectra have also the short wavelength maxima at 686 and 695 nm. Deconvolution of the low temperature spectra reveals two more minor bands at 680 and 703 nm [61-65].
As the red maximum of the excitation spectra is shifted by several nanometers to shorter wavelengths compared to the main absorption maximum of chloroplasts (676 nm), it is logical to ascribe fluorescence of the phosphorescence-emitting chlorophyll to the short wavelength forms 680, 686, and 695 nm. According to Murata et al., the contribution of the short wavelength fluorescence (600-700 nm) to the overall fluorescence spectrum of spinach chloroplasts is 25% [62]. A similar value was obtained by Litvin et al. for bean chloroplasts [64, 65].
The general yield of the low temperature fluorescence of chloroplasts obtained by Murata et al. upon excitation the Chl b band (475 nm) was 75% [62]. We repeated this measurement upon excitation the absorption band of Chl a (440 nm). As a reference, solutions of Chl a in ethanol were used. For the first try we used relatively dense chloroplast suspensions with absorbance equal to 0.4 at 676 nm at 77 K. The yield of overall fluorescence was estimated to be 15% [39]. This value is now corrected by using for fluorescence measurement dilute chloroplast suspensions in which reabsorption of fluorescence is reduced. As references, chlorophyll solutions in diethyl ether and pyridine were employed whose fluorescence yield was shown to be 55-60% [30]. When the paper [39] was published, the paper [30] has not appeared yet and also we did not know that at 77 K the fluorescence yield in ethanol is two times smaller than in pyridine and ether. As a result (Table 4), we obtained that the overall fluorescence yield is ~30%, two times smaller than in Murata's measurements. For further analyses, we used the average value 55% for overall fluorescence yield and 14% for the short wavelength bands.
It is natural to propose that the ratio φph/φf for molecules of the phosphorescence-emitting chlorophyll is the same in mature leaves and etiolated leaves after 1 h of greening. As shown in Table 4, the yield of chlorophyll phosphorescence in greening leaves (φf)etiol ≈ 40%. Hence using Eq. (3) one can obtain:
(φf)mature ≈ αchl × (φf)etiol = 0.0004-0.0012. (4)
Comparing this value with the quantum yield of the short wavelength fluorescence of chloroplasts (14%), one arrives to the conclusion that the phosphorescence-emitting chlorophyll makes up 0.3-1% of the short wavelength fluorescence of chlorophyll in chloroplasts.
We tried also to reveal the phosphorescence corresponding to the long wavelength fluorescence at 737 nm. It is likely that energy of the singlet–triplet splitting (ΔEst) for this fluorescence band is equal to ΔEst for the main fluorescence band of chlorophyll in the greening leaves. From the maxima of chlorophyll fluorescence and phosphorescence spectra indicated in Fig. 3 one can obtain that ΔEst = 4100 cm–1. Therefore, the phosphorescence maximum of this form should be located at ~1050 nm. From linear dependence between the energy of triplets and logarithm of their lifetimes, which was shown to be valid for chlorophylls [27, 36, 42, 43], one can calculate that the lifetime of this band should be ~0.5 ms. This value corresponds to the technical limit for temporal resolution of our set-ups. In agreement with this estimate, it was observed that aggregated molecules of bacteriochlorophyll c having the absorption maximum at 725 nm, emitted phosphorescence with the maximum at 1060 nm and the lifetime 0.6 ms [19, 20, 27, 33-35].
Comparison of Figs. 3 and 4 supports the assumption that long wavelength phosphorescence might exist in mature leaves. One can see that in mature leaves the maximum at ~1100 nm was two times smaller than the main maximum of the phosphorescence spectrum. In etiolated leaves after 1 h of greening, the phosphorescence maximum at ~1100 nm is three times weaker than the main phosphorescence band. Special experiments made to reveal a long wavelength phosphorescence band showed that upon shift of excitation to longer wavelengths, the relative intensity of phosphorescence at 1100 nm increased compared to the main phosphorescence maximum. However, insufficient sensitivity of our technique to luminescence in this spectral and temporal region does not allow us to get a final solution of this problem.
Thus, this review briefly describes the history of discovery of low temperature (77 K) phosphorescence of chlorophylls and characterizes parameters of phosphorescence of Chl a in solutions, certain model systems, greening leaves just after the Shibata shift, and in mature leaves and thalluses of macrophytic algae. It was shown that the phosphorescence of newly formed chlorophyll in greening leaves resembles best the phosphorescence of the short wavelength aggregates (probably dimers) in chlorophyll solutions. At this stage of development of leaves, the phosphorescence belongs to the bulk chlorophyll of leaves. The quantum yield of the chlorophyll triplet state is ≥25%. Further (after Shibata shift) formation of the photosynthetic apparatus caused strong decrease of the phosphorescence yield, which reached a minimum after 48 h of greening. In mature leaves of normal plants grown under normal illumination, the phosphorescence yield is 1000 less than in etiolated leaves after the Shibata shift. This value is stable in leaves of different plants. As a result of analysis of spectral and kinetic parameters of chlorophyll phosphorescence in leaves, isolated chloroplasts, and thalluses of macrophytic algae, three spectral forms of phosphorescence-emitting chlorophyll were observed with the main maxima at 955, 975, and 995 nm and the lifetimes ~1.9, ~1.5, and 1.1-1.3 ms. Excitation spectra of chlorophyll phosphorescence measured in the transparent thalluses of macrophytic green and red algae showed the maxima of Chl a and accessory pigments – carotenoids, Chl b, and phycobilins. The data indicate that phosphorescence is emitted by the short wavelength forms of Chl a, which are coupled with the light harvesting complex but their triplets are not quenched by carotenoids.
The concentration of the phosphorescence-emitting chlorophyll in mature leaves and its contribution to the overall chlorophyll fluorescence have been estimated. As a reference, phosphorescence of the newly formed chlorophyll in greening leaves was employed. It is shown that in mature leaves and chloroplasts the relative concentration of phosphorescence-emitting chlorophyll is 0.1-0.3%. The contribution of these molecules to the short wavelength (600-700 nm) fluorescence of chlorophyll was estimated to be 0.3-1%.
An attempt was made to reveal the phosphorescence corresponding to the long wavelength fluorescence at 737 nm, which dominates in the fluorescence spectra in leaves and chloroplasts (Figs. 4 and 5). Analysis showed that the spectral maximum of this phosphorescence should be at ~1050 nm. The lifetime should be ~0.5 ms. The experimental data indicate that this phosphorescence might exist in mature leaves and chloroplasts. However, insufficient sensitivity of our technique to luminescence in this spectral and temporal region does not allow us to a get final solution of this problem.
The nature of the phosphorescence-emitting chlorophyll is presently not quite clear. In previous papers, we suggested that phosphorescence belongs to newly synthesized chlorophyll in the centers of pigment biosynthesis [44, 45]. The concentration of the phosphorescence-emitting chlorophyll is consistent with the concentration of young chlorophyll estimated by the Shlyk school [66]. Indeed, it was shown in experiments of our laboratory that phosphorescence of chlorophyll and protochlorophyll strongly increased if leaves were kept in darkness for many hours, especially in the presence of 5-aminolevulinic acid and metal chelators [37, 67]. However, this suggestion is not quite consistent with the fact that several spectral forms of the phosphorescence-emitting chlorophyll were observed in chloroplasts developed under normal illumination conditions. Another assumption states that phosphorescence belongs to chlorophyll of the reaction centers of PS-2 [44, 45]. It is known that chlorophyll molecules in these reaction centers are spatially separated from carotenoids. As a result, carotenoids do not quench chlorophyll triplets, and therefore their lifetime is long, sufficient for efficient singlet oxygen generation [68, 69]. Preliminary data of our laboratory showed that indeed, in isolated reaction centers (D1D2-cyt b559 complexes) strong millisecond chlorophyll phosphorescence appears [70]. However, the samples used for this experiment contained rather much uncoupled chlorophyll molecules. Presently, more detailed studies are in progress. Again, the existence of several spectral forms of the phosphorescence-emitting chlorophyll in normal chloroplasts is not quite consistent with this assumption. It is not excluded that under normal conditions, when reaction centers are inside native (not damaged) structure of chloroplasts, the reaction center triplets are not formed or are quenched. According to the third idea, normal chlorophyll–protein complexes of chloroplasts generate a certain amount of triplet, which are not quenched by carotenoids. Probably, this is a consequence of the complex structure of the pigment apparatus. In this case, the "constant" (0.1-0.3% concentration of phosphorescence-emitting chlorophyll) found in our experiments shows the minimum concentration of carotenoid-detached chlorophyll molecules, which plants can stand. It might be that further reduction of the yield of chlorophyll triplets is not effective. It is simpler to protect native structures from photodynamic activity of this small group of chlorophyll molecules. This assumption correlates with the data of Santabarbara et al. [71], who, using FDMR, also observed triplet states of chlorophyll not connected with photosynthesis reaction centers.
Nevertheless, in aerobic conditions triplet molecules of chlorophyll and its precursors in biosynthesis transfer their energy to O2 with formation of reactive singlet oxygen (1O2), which readily oxidizes biologically important molecules [21, 22, 44, 45, 51, 72]. It is thought that this process is responsible for photoinhibition of photosynthesis and photodestruction of the photosynthetic apparatus ([44, 45, 69, 72] and references therein).
Based on these ideas, we expect that the intensity of the low temperature phosphorescence should correlate with the rate of photodestructive processes under physiological conditions. The first experiments supporting this assumption were carried out by the authors of this review in collaboration with A. Faludi-Daniel (Szeged, Hungary). It was shown that in lycopene and ζ-carotene mutants of maize, in which the rate of photodestruction of chlorophyll is much stronger than in normal plants, the phosphorescence yield is also higher, and what is more, the phosphorescence yield and the photodestruction rate correlate [38]. Later, this problem was studied in detail [44, 45, 57]. Apparent correlation between the phosphorescence yield at 77 K and chloroplast photodestruction at room temperature was revealed. This fact allows for the conclusion that namely the phosphorescence-emitting fraction of chlorophyll molecules is responsible for photodynamic destruction and photoinhibition of the photosynthetic apparatus. Thus, the yield of chlorophyll phosphorescence shows the degree of plant protection against photodynamic action of the native pigment apparatus. In particular, measurement of phosphorescence allows for investigation of mechanisms and efficiency of action of photodynamic herbicides [44, 45, 59, 67].
Thus, the data indicate that phosphorescence provides unique information on the photophysics of pigment molecules, molecular organization of the photosynthetic apparatus, and mechanisms and efficiency of photodynamic stress in plants.
The authors thank the colleagues whose names are cited in the list of joint research papers for collaboration in the experimental work. Support of the Program "Molecular and Cell Biology" of the Russian Academy of Sciences is gratefully acknowledged.
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1. Place extra 4 tablespoons of extra virgin olive oil in a skillet and bring to medium heat.
2. Place water for the spaghetti in a separate bowl and bring to a boil. Cook the spaghetti according to the package instructions.
3. While the skillet heats, place the egg white in a bowl and whisk it until smooth.
4. Place the almond flour and parsley in a separate bowl. Sift together until thoroughly combined.
5. Place one sole filet in the egg then immediately into the almond flour coating it generously. Place the filet in the pre-heated skillet. Repeat for the other sole filet.
6. Cook 3 minutes on each side until slightly golden brown. Gently remove the sole filets and place on a plate.
7. Place the white wine and lemon juice in the skillet. Use a spoon to scrape any browned portions from the bottom of the skillet and stir into the mixture.
8. Stir in the capers and add remaining 2 tablespoons of extra virgin olive oil.
9. Cook 5 minutes until the sauce has slightly thickened.
10. Place spaghetti and fish in the pan coating with the sauce. Serve immediately topped with more parsley and grated parmesan.


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BITS Bits of Information, Transmitted and Stored
Home › People › Brian Kurkoski
Brian Michael Kurkoski
Japan Advanced Institute of Science and Technology
School of Information Science
1-1 Asahidai
Nomi, Ishikawa, 923-1292, Japan
http://brian.kurkoski.org/
kurkoski@ieee.org
Academic and Research Positions
Professor Japan Advanced Institute of Science and Technology, Nomi, Japan. April 2020-present
Associate Professor Japan Advanced Institute of Science and Technology, Nomi, Japan. April 2012-March 2020
Associate Professor University of Electro-Communications, Tokyo, Japan. April 2007-March 2012
Research Associate University of Electro-Communications, Tokyo, Japan. July 2006-March 2007
Postdoctoral Researcher University of Electro-Communications, Tokyo, Japan. July 2004-June 2006
Visiting Researcher Hitachi Central Research Laboratory, Tokyo, Japan. June-December 2000
Graduate Student Researcher University of California, San Diego (UCSD), Center for Magnetic Recording Research. June 1999-June 2004
Hardware Engineering Manager, Design Engineer, Z-World, Inc, Davis, California, USA. 1995-1998
Design Engineer, Skyline Test Equipment, Palo Alto, California, USA. 1993-1995
Ph.D. 2004. University of California San Diego, Electrical Engineering (Communication Theory and Systems).
M.S. 2000. University of California San Diego, Electrical Engineering.
B.S. 1993 California Institute of Technology, Pasadena, California, Engineering and Applied Science (Electrical Engineering).
Organizing Activies
IEEE Information Theory Society, Digital Presence Committee, Chair, 2022–2023
IEEE Information Theory Society, Board of Governors, Member, 2021-2023
2021 IEEE Information Theory Workshop (ITW2021) in Kanazawa, General Co-Chair
IEEE Information Theory Society, Online Committee, Chair, 2019–2021
IEEE Communications Society, Data Storage Technical Committee, Chair (2017-2018) and Secretary (2013-2016)
2021 IEEE International Symposium on Information Theory, Publicity
International Symposium on Information Theory and Its Applications (ISITA), Publicity Co-Chair, 2014, 2016, 2018, 2020
IEEE Information Theory Society, Conference Committee, Member, 2016-2019
Japan-Singapore Workshop on Coding and Information Theory, Co-Chair, 2018
IEICE Research Society of Information Theory and its Applications, "Board of Govenors," Member, 2015-2016
2014 IEEE Information Theory Workshop (ITW), Publicity Chair
Workshop on Coding for Flash Memories (Japan) 2010, 2012, 2013
Associate Editor for IEEE Transactions on Information Theory
Guest Associate Editor for IEICE Transactions Special Section on Information Theory and Its Applications (2015, 2011)
Associate editor for IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences (2010-2014)
Technical program committee chair:
IEEE International Conference on Communications - Selected Areas in Communication, Data Storage 2014
International Conference on Computing, Networking and Communications ICNC 2013, Data Storage Technology and Applications, Symposium Co-Chair
Technical program committee member (or equivalent):
IEEE International Symposium on Information Theory (ISIT), 2020, 2022
International Symposium on Information Theory and Its Applications (ISITA) 2010, 2014, 2020
International ITG Confernce on Systems, Communications and Coding (SCC) 2019
Non-Volatile Memories Workshop (NVMW) 2013, 2014, 2017, 2019, 2020
International Symposium on Turbo Codes & Iterative Information Processing (ISTC), 2016, 2018, 2021
IEEE International Conference on Communications ICC
Selected Areas in Communication - Cloud Computing, Networking, and Storage
Selected Areas in Communication – Cloud & Fog Computing, Networking, and Storage Track 2020
Selected Areas in Communication Symposium (Data Storage Track) 2013, 2018
Communication Theory Symposium: 2014, 2017
International Wireless Communications and Mobile Computing Conference (IWCMC), Wireless Networking Symposium, Wireless Networks 2017
IEEE Global Communications Conference (GLOBECOM) 2008, 2010, 2013, 2016
IEEE Global Conference on Signal and Information Processing, 2016
International Conference on Computing, Networking and Communications (ICNC) 2012
International Symposium on Communications & Information Technologies (ISCIT) 2011
IEEE Intermag, Technical Review Committee (2015 Recording System II Session, 2006)
Reviewer for: IEEE Transactions on Information Theory, IEEE Transactions on Communications, IEEE Transactions on Magnetics, IEICE Transactions.
Member of IEEE, IEICE.
2019-2022 Ministry of Education, Science, Sports and Culture Grant-in-Aid for Scientific Research (B). 19H02137 "Lattice Codes for Gaussian Wireless Networks." 11,800,000 yen (direct amount).
2019 Toshiba Memory Research Encourangement Grant, "Machine-Learning Enhanced Signal Processing for High Reliability Data Storage."
2016-2017 Ministry of Education, Science, Sports and Culture, Fund for the Promotion of Joint International Research (Fostering Joint International Research). JP 15KK0005 "LatticeNET: Practical Lattice Codes for Cooperative Wireless Networks." 5,400,000 yen (direct amount)
2014-2016 Ministry of Education, Science, Sports and Culture Grant-in-Aid for Scientific Research (B). 26289119, "LatticeNET: Practical Lattice Codes for Cooperative Wireless Networks." 12,400,000 yen (direct amount).
2012 IEICE Service Award. For service as an Editorial committee member of the English-language journal.
2011-2013 Ministry of Education, Science, Sports and Culture Grant-in-Aid for Scientific Research (C). 23560439, "Signal Processing and Coding Methods for High-Density Flash Memory Systems." 4,000,000 yen (direct amount)
2007-2008 Ministry of Education, Science, Sports and Culture Grant-in-Aid for Scientific Research (C). 19560371, "Decoding Methods for Non-binary LDPC Codes Using Information Theoretic Approaches" 1,500,000 yen (direct amount)
2004-2005 JSPS Postdoctoral Fellowship. A two-year fellowship supported by the Japan Society for the Promotion of Science, number 00004908, 2004.
2004 Sheldon Schultz Prize for Excellence in Graduate Student Research. Center for Magnetic Recording Research, University of California, San Diego.
2000 Jacobs Fellowship. Department of Electrical and Computer Engineering, University of California, San Diego.

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How do I use MONEY or Current in NSQL?
MONEY (<currency column>) specifies that the value is a monetary amount and that the currency is specified by the column alias in parenthesis. The currency must also be part of the SELECT statement.
Re: How do I use MONEY or Current in NSQL?


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Repercussions of the Rothko Sale
The Marguerite Hoffman case against David Martinez and the sale of the Rothko in question earlier this month has provoked some debate in Dallas about the nature of bequests, Peter Simek writes in D Magazine:
although Hoffman's Rothko brings new attention to the in-flux nature of the donations, the sale isn't very significant to the museum's potential collection. According to a source, the Hoffmans possess a second Rothko of better quality than the one recently auctioned. In this case, unloading the painting made both economic and curatorial sense.
However, the Rachofsky sale of a balloon sculpture by Jeff Koons (Balloon Flower (Magenta)) two years ago is another matter. The Koons piece was one in an edition of five, and it was both representative and a high quality example of the work from the Neo-Pop Art movement of the 1990s, an art movement for which the DMA possess few if no significant holdings to my knowledge. The sale of the Koons made sense in market terms at the time – fearing the Neo Pop bubble was going to burst with the rest of the economy. But the sale didn't make sense in terms of creating a representative and significant collection for the Dallas Museum. The DMA is now out a significant work by a major artist. If the collection was being cared to by a museum curator, and not an independent collector, that kind of sale simply wouldn't have happened.
So there's the issue: do the terms of the donation agreement create a situation in which the DMA is unable to fulfill its function as a public museum with the more academic and archeological aim of collecting works that, as the DMA's own mission statement puts it, "contribute to cultural knowledge." It is this mission, after all, that allows for the museum's non profit status, which allows it to leverage tax deductions as incentives for major donations in the first place.
In Wake of Rothko Sale, Questions Loom Over 2005 Donations' Impact on Museum's Future (D Magazine)
Marguerite Hoffman Speaks
The Suit and the Secret Rothko
Are the Lawyers Ruining Restitution?
Marguerite Hoffman on the Nature of a Collector's Promise
Who Says There Are No Sales?
Basque MoCA?
Filed Under: Museums
How Park West Sold $93m in Peter Max Paintings
From Smoking Ruin to Masterpiece Market and Beyond: A Pivotal Decade in the Art Market


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Home » Latest Articles » News and Entertainment » Demi Lovato's Spanish Song With Luis Fonsi Could Be the Next "Despacito"
Demi Lovato's Spanish Song With Luis Fonsi Could Be the Next "Despacito"
Demi Lovato has a new single and we're thinking it's going to blow up and be the next "Despacito." Here's why: she's singing in Spanish and it's a duet with Luis Fonsi, need we say more? The song is titled "Echame La Culpa" (which translates to: give me the blame) and it officially drops tomorrow, but the singers have been teasing it for days!
According to Univision, Fonsi spoke very highly about Lovato and his collaboration with her. "My next song is a collaboration with Demi Lovato, who is an international artist and there I stay on that same path and with the same desire to hear the whole world singing in Spanish. This song will be bilingual so it's all about uniting cultures, uniting languages, and continuing to dance and have a great time."
On Nov. 13, the duo spoke about their new song together. "I have a really good feeling about the song," Fonsi said, according to People magazine. "I just got the chills," Lovato responded."
From the teaser, we are so into Lovato's Spanish accent, and she did tell Fonsi that she'd practice her Spanish. It's paid off. Here's a snippet of the song.
And the video looks amazing as well.
Do you think this song will be able to top "Despacito"? Either way, we're so happy to hear that Lovato is embracing her Spanish roots.
In 2014, Lovato spoke about her Mexican background.
"Growing up in America, I never really appreciated my culture," Lovato told the Glam magazine."I knew what being Hispanic was, but I thought that since I didn't look Hispanic, I was white."
But that changed over the years, Lovato said.
"I tried to conform to what everyone thinks is beautiful," Lovato added. "But my genetics gave me a curvy figure, and I've come to understand that in the Latina culture, that is beautiful. I no longer look at my body and think, Oh my gosh, I have such a fat butt. Or, I hate my thighs. On some days I don't love them. But, you know, that's one of the things that makes me me."


Early in the morning we set out on a bus from Haifa and travel to Jerusalem, a historic city where we plan to spend two nights. We stay close to the Gate of Damascus, one of the entrances to the Old Town.
The Old Town, Jerusalem, is quiate a unique place to be. Different groups of people – Muslims, Orthodox Jews, Christians and many tourists of different religions as well as atheists come here. The city is surrounded by the walls built in the 16th century in the era of Ottoman rule. The walls are 4 kilometers long, 12 meters high and 2,5 meters wide. Also, there are many guard towers as well as several gates.
We walk through the Gate of Damascus. Then we get streets crowded with Arabian vendors. Soon their style of persuasion makes us sick and tired. However, you can really bargain and we manage to buy souvenirs at the cheapest price (compared to the rest of our stay). We trully enjoy shopping at Isreali vendors. Their products are beautiful and good prices, without bargaining even. Their stores are mostly situated at the edge of the Old Town.
We set out down the streets to one of the most important sites of Christianity. It doesn't seem important at all from the outside. We talk about the Church of the Holy Sepulchre. Built upon the place where Jesus was crucified, burried, and resurected (on Golghota) in the present Christian district. The original temple was built as soon as in the 4th century and saw a renovation in the 12th. Inside it is quite crowded. There the Stoene of Anointing. Crowds of believers hallow all kind of stuff they carry with. The body of Jesus Christ was laid here. As we are atheists it was quite strange yet interesting spectacle. To the left you enter Anastasis rotunda with the tomb of Jesus Christ in the midle. It is situated in the chapel called Edikula. You can take a look inside the chapel. Be ready for long lines however.
Upon our visit to the Church of the Holy Sepulchre we walk around the Etiopian convent. Its typical feature is a small dome sitauted on a small courtyard. Through the dome light illuminates St Helena's chapel in the eastern part of the Church of the Holy Sepulchre. Close from there, you may find the church of Alexander Nevsky built in the year 1859. Then go on around a lutheran church of Christ the Saviour featuring a narrow belfry. Then we pass Muristan, a busy quarter with stores and cafes. By spotting a silver dome we realize that we reached St John the Baptist's cuhrch, the oldest church in Jerusalem built between the years 450–650.
Then we make farewell to the Christian district in the Old Town. We head to the Jewish quarter. The most popular place there is the Western Wall. This huge wall is the holiest site in Judaism. We see a number of Jewish men and women to come here and pray. In separated sections, however. On holidays and Fridays the site becomes bussiest. The wall is 32 meters high. Howeover, one third of it is below the ground. It consists of huge boulders some of which are over 7 tons. Believers have stuck papers with their prayers here since the 18th century. Now tourist make this too. Instead of prayers, however, they put there their wishes.
In the second part we are about to visit the famous Temple Mount shrine inside Muslim district. However, we learn that to enter the compound is possible only between half past seven and ten o'clock in the morning. Hence, note for yourselves that you need to plan your trip there good. All entrances are guarded by quite unpleasant soldiers carrying machine guns. Therefore, we better go away and relax while drinking a local great drink – freshly made pomegranate juice. Try it.
Before we head back to the south of Israel to the city of Eilat, we make a short trip outside to the neighboring state. Palestine. Less than 4 million inhabitants live there, mostly Muslims and Arabic speakers here. There are ongoing conflicts between Israel and Palestine stemming from territorial disputes and delimitation of borders.
Not only the Old Town of Jerusalem is hiding real tourist treasures, so today we go for a walk that directly behind city walls. We start on Mount Sion, whose name is only another expression for the State of Israel. This mountain is located behind the southwest wall of the Old Town, the biblical King David's burial ground, and the very last supper of the Lord happened here.
On train we leave Tel Aviv in the morning. Traveling north we are about to visit the city of Haifa and also a national park there. It is a very comfortable ride for us. The train is on time and wi-fi is available at train stations.
We leave the amazing Ein Gedi oasis and follow the main road along the Dead Sea. We area about to visit the famous ancient fortress of Masada. The historic sight belong to UNESCO world heritage and was listed in 2001. It is one of the main tourist attractions of Israel.
A flight to Israel takes about 4 hours. Add a shy hour to that which takes you to get from Ovda airport to downtown Eilat. We attive on Thursday at 11 pm. Only at half past one am we reach the bed. Also, be careful when considering accommodation. Cheap accommodation is rather not operated legally. Therefore, arrange with owner your excat time of arrival. I reccommend you to search through rating of accommodation. Our first impression over dirty room is self-expressive.
On this day, we visit the famous land of Qasr al-Yahud on the eastern bank of the River Jordan. Then we set out to Ein Gedi osasis.
Caesarea or Caesarei, or Kaisareie in Greek, is a city located near the larger city of Hadera, in Israel, on the shore by the Mediterranean Sea. This historically important city is one of the most popular cities in the country. Why is it so we tell you in our article.
In the article today we continue on our journey across Israel. We move to the third largest city in the country, to Haifa. This port offers not only a splendid view of the Mediterranean Sea but also tolerant atmosphere and beautiful nature.
Today we move to one of the most popular archeological sights of the world, to Qumran located at northwestern shore of the Dead Sea, near the city of Jericho. This place is famous for finding of the so called Dead Sea Scrolls, also known as the Qumran manuscripts.
On the borderline of Jordan and Israel there is Earth's lowest elevation on land, the Dead Sea. This endorheic hypersaline lake is popular tourist attraction, golden mine for companies extracting medical salt as well as a palce of rich and interesting history.
There are many sights in Israel's largest city of Jerusalem. There are also many sacred places and symbols of many religions. One of these sights is the Western Wall or the Wailing Wall that attracts millions of pilgrims from all-around the world to say their prayers.


I was wondering if there's anyone around here who knows the lyrics (and if possible, English translation) of the song Diweddglo by Y Reu. I discovered it from MrGWallCymraeg's Welsh language playlist on YouTube. I've tried searching for the lyrics, but I can't find them.
Here's a link to the song within the playlist.
The song just carries on from here repeatinf the "Ti jyst...." lines.
Just a couple of grammar notes too. In the line "Bryd symud ymlaen", the "Bryd" is "Pryd" that has been mutated, I'd imagine since the full sentence would normally be "Mae hi'n bryd symud ymlaen" and even though the verb and pronoun have been dropped the mutation was left. "Drem" is not a word I'm familiar with, though "ap geiriaduron" suggests that is is the softly mutated form of "Trem" which means "Gaze, Glimpse, Look" ( all feminine nouns not verbs), I'm not sure if this is the correct word here though since I can work out how those translations make sense in that sentence. Otherwise I'll show all the mutated words in there unmutated forms here.
"Gwela"-"I will see" "Dim"- In this instance it show that the sentence is negative. "Call"-"Sensible"
These are all examples of soft mutation by the way I can also explain why each one occurs if you'd like. Also the song title itself "Diweddglo" means "Conclusion" but only "Conclusion" in the sense of the end of a story not the paragraph at the end of an essay which is "Casgliad".
Diolch yn fawr! This is all immensely helpful. Thank you so much for all of the explanations.
Just listened to the song again and he doesn't say "Drem" he says "Drefn" just with an almost silent "f". I've edited my original post to show this.
Ok, so it rhymes with "anrhefn". Again, thank you so much.
Yeah though most of the time people will pronounce the f properly he's just done it ij the song so it sounds better.
Shwmae! Glad you enjoy it - I use it often in class when teaching, and that particular song is one of my favourites :) Ellis has given a good translation. The Sŵnami songs are all very good, too.
Update: Thanks for suggesting Swnami, they're one of my go-to bands now, and I couldn't remember where I had heard of them in the first place. I just came across this old post, and now I know who to thank!


Don Brash should have had the opportunity to shoot himself in the foot among the free-thinking Massey student body.
Hearing Don Brash express his views never ceases to make me cringe.
Almost everything he says is anti-Maori and the polar opposite to where my thinking is.
Part of the cringe is that I profited from those same views when he expressed them in his Orewa speech back in 2004.
It was then that National's polling sky-rocketed and, after an approach from then party president Judy Kirk, I decided to stand for Whanganui one more time on a National ticket — and finally won after failed attempts in 1999 and 2002.
Read more: Chester Borrows: How are you getting on with your 'dash'?
Any serious analysis of the 2005 election makes it clear that the Nats would have struggled but for Brash's speech.
Those very edgy views were expressed in billboards and further speeches and we candidates stood there and watched.
Not being in power and desperately wanting to win can makes us do things that, with hindsight, we would rather forget.
A change of leadership, thankfully, saw the party take on a different view — incoming leader John Key made the statement that Maori were tangata whenua within a day of his leadership being announced.
In spite of the meteoric rise from 18 per cent to 45 per cent under Don Brash and his controversial race-related comments, when John Key took over and signalled his opposing view, his polling did not drop but continued to climb. I felt a lot more comfortable.
But Don has built on his polarising and divisive comments and, in fact, being racially divisive has become his brand now.
The last conversation I had with him ended with me telling him that his preferred policies would take us back to the 1970s. He agreed, saying the 1970s race relations were exactly where we should be as a country.
Though bigoted and skewed views, Don would have well-researched as to why he truly believed this. So does that mean that although I wouldn't cross the street to hear those views, they shouldn't be aired in public?
It seems that when somebody from Norway posted on social media that someone should take a gun along when Brash turned up to speak at the Massey University campus, the vice-chancellor Jan Thomas — without consulting the police to assess the risk — canned the invitation, effectively banning him from speaking at Massey.
No matter which way you dice it, it looks like she was hiding behind "security concerns" for achieving a gagging order.
I would have thought allowing Don Brash sufficient opportunity to shoot himself in the foot among the free-thinking Massey student body would have achieved a far higher objective.
Now she has made a martyr of him and opponents and proponents alike are rallying to support his right to speak, which Don — in his "geekiest-kid-in-form-2" kind of way — will interpret as support for his views which will increase in volume and frequency.
Other venues and opportunities will succumb to the newsworthiness of the scrap, and will give him the oxygen he craves rather than risk the approbation of those crying foul.
You'd think that a university campus would be exactly the right place to host a contest of ideas.
You'd wonder how such a delicate flower could rise to the giddy heights of vice-chancellor, and why Don Brash should be spared the challenge to his 1970s – fifty years past its used by date — view of New Zealand's future.


"Now, the creative minds behind the Shocker and Ion are changing the face of paintball again with the eNMEy™. With a purely pneumatic design, the eNMEy™ is a regulated spool valve marker in the same price range as entry level blowback paintguns. There's no hammer, mainspring or sear in the eNMEy™. You've got to shoot it to believe it," says GOG's Adam Gardner, referring to the smooth performance made possible by the marker's spool valve design. "That's why we're inviting paintball techs from around the world to take the eNMEy™ tech class free of charge at this year's World Cup – and to leave with an eNMEy™ of their own.""
The GOG eNMEy is set to be released in October of this year, and appears to be a mechanical version of the Smart Parts Vibe/GOG eNVy due to the apparent single trigger.
My name is Nate, and I've been playing paintball for over three years. This is my blog, where I write about paintball markers, events, strategies, and more. Pew pew pew!
Gone Paintballing Blog was started in January of 2012. It is a paintball blog focused on the ever growing sport of paintball. It features paintball news, reviews, and more. Information and reviews on paintball markers and paintball loaders. Featuring paintball guns such as the Bob Long G6R and Invert Mini. Event coverage and videos, as well as tips and paintball techniques. We strive to keep our paintball information relevant, up to date, and free of factual and grammatical errors. If you have any suggestions for what paintball event or paintball gear that should be written about, feel free to comment with suggestions. Always remember to keep your paintball mask on at all times when playing, and stay safe!
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This roasted rutabaga (swede) dish is a wonderful addition to your dinner table. Sweet and fragrant with an earthy note, this side dish will have guest begging for the recipe. Just be sure to cook this for long enough to get the good caramelly bits.
Rutabaga is a yellow brown root vegetable that is part of the cabbage family.
It is a very underused vegetable, possibly because it looks pretty ugly in the shops, and people are worried about peeling and preparing it.
It is called swede in many parts of the world, but the term rutabaga is unique to the US.
Rutabaga can be boiled, steamed or roasted.
Here we are roasting it with maple syrup to give it a wonderful sweet edge.
Check out my Cheesy Rutabaga and Carrot Casserole for how to boil rutabaga.
What is the difference between Turnip and Rutabaga?
Although they are similar, turnips have a slightly more bitter flavour. You could use turnip in this recipe, but the flavor will be quite different.
Rutabaga is a really healthy alternative to potatoes. When roasted they are crispy on the outside and fluffy inside like a roast potato but with significantly lower carbs.
This roasted rutabaga dish is pretty special. We all know I love roasted veg!!!! If I can roast it, then I will!!! And I haven't found a vegetable that isn't delicious when roasted. In fact many vegetables taste better roasted! Take my roasted broccoli dish. Honestly it is amazing. And my roasted Brussels sprouts with fish sauce vinaigrette have been know to convert non-sprout eaters!!!!!
If you love roasted veg as much as I do, then check out my roasted veg recipe collection, full of delicious ways to cook your 5 a day.
I served this roasted rutabaga up with a steak and side salad, but they would be fabulous as part of a roast, or along side a grilled chicken dish.
Please use really maple syrup here, flavoured syrups won't give you the wonderful flavor or sticky crispy finish.
Pin these Roasted Rutabaga with Maple Syrup for later. Pin it here.
This roasted rutabaga (roasted swede) dish is a wonderful addition to your dinner table. Sweet and fragrant with an earthy note, this side dish will have guest begging for the recipe. Just be sure to cook this for long enough to get the good caramelly bits.
Pre-heat the oven to 200ºC/390ºF. Place a roasting tin the oven to heat up.
Peel the swedes and cut them into large chunks.
Place the swedes in a and dress with the olive oil, maple syrup and dried thyme.
Add in a good sprinkle of salt and pepper and toss to combine well.
Spoon the swede into the roasting tin, reserving any dressing that has pooled at the bottom of the bowl.
Roast in the oven, for 25 minutes, then drizzle over the reserved dressing and cook for a further 15-20 minutes until crisp and golden.
Use real maple syrup here, the flavored syrups burn quickly and don't have the depth of flavor you need.
This roasted rutabaga was originally posted in 2016. But has been updated with new pictures, dual measurements and nutritional information.
I have a beautiful reader called Dorothy, she and I have become friends. We have so much in common, amongst them is a love of cocktails and seafood!!!!
Anyway, Dorothy is my American interpreter 😉 If I am unsure of anything then I check with her. The international language of food isn't always clear cut. I am pretty lucky as when I moved to Australia I had to adopt the words capsicum, zucchini and eggplant (I am sure there are plenty more!!!!) so my food language has evolved. Add to that my obsession love of the cookery channel and the plethora of US cook shows, I am pretty well versed in arugula, cilantro etc. But I still like to check things with Dorothy.
I'm super excited I found your recipe. My daughter gets fresh vegetables delivered to our home and it's always a surprise what's in the box. We have never eaten rutabaga before and I never knew it was called Swede. Your recipe sounds delicious I'm looking forward to making it. We love roasting vegetables. Maple syrup is a huge plus . Thank you for sharing and God Bless.
Oh Carmela, thank you so much for taking the time to reply.
I love the food delivery boxes as they introduce people to such delicious ingredients.
I hope you and your daughter enjoyed the rutabaga.
We call them rutabaga here in Canada too. I have never heard them called a swede. Love them! I've never tried them roasted before – only boiled and mashed or parboiled then finished in a quick sauté. I am about to put it in the oven with freshly boiled maple syrup to go along with local trout. Yum!
OH MAN!!!! Freshly boiled maple syrup sounds amazing! I bet this will be out of this world with your own maple!
Oh that looksmperfectly Roasted. I love the combination of maple syrup and thyme.
mmm this rutabaga looks very tasty! I like the fact that this recipe can be prepared quickly and easily. It's great for dinner for me and my family. Thanks for sharing this recipe!
You know, I haven't cooked much at all with rutabagas, and I also didn't know they go by swedes outside the US! Love this roasted healthier alternative to potatoes with the maple syrup.
I have never tried rutabaga before. Could you please let me know what is it and where can I find it?
It is a root vegetable Gujan. You can usually find it near the carrots and parsnips in the grocery store. It is yellowy brown and similar shape to a turnip.
Roasted Rutabaga sounds amazing! My parents produce pure maple syrup on their farm, so we'll definitely be trying your dish! Bet these flavors would be perfect on fingerling potatoes as well!
OH!!! I am super jealous of that Jessica!!!! I want home-made maple syrup!
Ooooh it would be fabulous with fingerlings!
This is the perfect alternative to potatoes and the seasonings in this recipe are perfect for getting the kiddos to eat them too!! Love!!
I agree – rutabagas are under utilized — and that's too bad, because they're really delicious. I've used them in soups and salads before, but this preparation looks delicious — and fairly easy to do. Will give your recipe a go this week — maybe with a rotisserie chicken.
You have such a lovely roast here! I've never tried roasting rutabaga before – this looks fantastic – such a perfect char!


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text:
Side Plates or Dessert Plates
6 Royal fruit dishes
31786 Royal fruit disheshttps://s3-eu-west-1.amazonaws.com/lovethecdn2/products/VILLERO4003686140325_1.jpg119.4119.4EUROutOfStock0Villeroy & Boch/dining/dinnerware/side-plates-or-dessert-plates/dining/dinnerware/diningEURPorcelain6-royal-fruit-dishes-16 Royal fruit dishes by Villeroy & BochA small serving of elegant white fruit dishes. Villeroy & Boch fruit dishes were designed more than 15 years ago for the Royal dinner service. It is one of the greatest achievements of the company, given that over the years they have sold many pieces, and the set is still in the catalogue. The refinement of the Royal fruit dishes is in their utter simplicity. The dishes are made of Bone Premium porcelain, thin and light, almost ethereal. The white color make these fruit dishes perfect to accompany any table set, even the most elegant or joyful and fun-loving. The shape is very simple, a circle with a diameter of 22 cm, with a slight groove in the middle which gives way to a wide flat edge. Elegant and linear, the Royal fruit dishes are also suitable for a buffet or an aperitif with friends. Despite the ethereal and delicate appearance, the excellent quality of the materials used by Villeroy & Boch make these fruit dishes dishwasher safe. They are also ideal as an original gift, thanks to the neutral colour that allows you to use them also with dishes of other collections. Not everyone uses the fruit dish, but you must take into account that in general these dishes are not presented during the meal, but only at the end of it, when all the rest of the dishes has already been cleared. A very versatile and practical set of dishes, designed for those who like to always have everything in order and enrich the table with small fine details. Villeroy & Boch also produces other elements of the set of Royal dishes, ideal to accompany the set of fruit dishes, with larger plates or even with serving plates of different sizes. They are perfect for those who love beautiful and luxurious things. Villeroy & Bochhttps://www.lovethesign.com/eu/villeroy-boch/6-royal-fruit-dishes-1
6 Royal fruit dishes by Villeroy & Boch
Measurements ø 22 cm
Materials Porcelain
A small serving of elegant white fruit dishes. Villeroy & Boch fruit dishes were designed more than 15 years ago for the Royal dinner service. It is one of the greatest achievements of the company, given that over the years they have sold many pieces, and the set is still in the catalogue. The refinement of the Royal fruit dishes is in their utter simplicity. The dishes are made of Bone Premium porcelain, thin and light, almost ethereal. The white color make these fruit dishes perfect to accompany any table set, even the most elegant or joyful and fun-loving. The shape is very simple, a circle with a diameter of 22 cm, with a slight groove in the middle which gives way to a wide flat edge. Elegant and linear, the Royal fruit dishes are also suitable for a buffet or an aperitif with friends. Despite the ethereal and delicate appearance, the excellent quality of the materials used by Villeroy & Boch make these fruit dishes dishwasher safe. They are also ideal as an original gift, thanks to the neutral colour that allows you to use them also with dishes of other collections. Not everyone uses the fruit dish, but you must take into account that in general these dishes are not presented during the meal, but only at the end of it, when all the rest of the dishes has already been cleared. A very versatile and practical set of dishes, designed for those who like to always have everything in order and enrich the table with small fine details. Villeroy & Boch also produces other elements of the set of Royal dishes, ideal to accompany the set of fruit dishes, with larger plates or even with serving plates of different sizes. They are perfect for those who love beautiful and luxurious things.
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text:
Home Home | News & Events | Former U.S. Ambassadors
By U.S. Mission OSCE | 18 January, 2017 | Topics: Civil Society and NGOs, Elections, Former U.S. Ambassadors, Human Rights
TRANSCRIPT: Ambassador Baer's Interview with Reuters
There will always be setbacks and steps backward amidst steps forward. But the message we should be sending to those who have attempted to undermine liberal democracy is that we will rebuild these institutions, and we will rebuild them stronger than they were when these people tried to destroy them.
By U.S. Mission OSCE | 18 January, 2017 | Topics: Former U.S. Ambassadors, Human Rights, Ukraine Crisis
TRANSCRIPT: Ambassador Baer's Interview with Der Standard (Austria)
One is that, in order to achieve leadership in that respect, putting human rights and democracy at the forefront and being clear that even though Austria is famously a neutral country, being neutral doesn't mean you're neutral vis-à-vis fundamental moral principles and political commitments.
TRANSCRIPT: Ambassador Baer's Interview with ORF TV (Austria)
"I think the big thing that the Foreign Minister and that the Austrian team can lead us on is really responding to this threat of authoritarian populism that we see rising in many parts of the OSCE area and outside of it as well, and responding with firm conviction and commitment to human rights and …
Response to the OSCE Chairman-in-Office, Austrian Foreign Minister Kurz | Statement to the PC
The United States looks to Austria to maintain the German Chairmanship's principled focus on supporting civil society and independent media, and promoting tolerance and non-discrimination throughout the OSCE region.
By U.S. Mission OSCE | 12 January, 2017 | Topics: Former U.S. Ambassadors, Statements, Ukraine Crisis | Tags: Minsk Agreements, Russia, Ukraine
Ambassador Baer's Interview with Gazeta.ru
One of the things that gets misunderstood is that while it is true that it is difficult to reach consensus today in the OSCE, on most things, there is agreement by at least 55 or 56 States. It is usually one or two holdouts. When it's one, it's usually the Russian Federation. And when it's …
By U.S. Mission OSCE | 13 December, 2016 | Topics: Arms control, Former U.S. Ambassadors, Human Rights, Statements, Ukraine, Ukraine Crisis | Tags: Russia, Ukraine
Press Availability by Ambassador Baer at the 2016 OSCE Ministerial Council
The top issue on the Ministerial this year was, as it has been for the last three years, the ongoing conflict in eastern Ukraine and Russia's role in violating Ukraine's sovereignty and territorial integrity. In fact, my delegation was listening carefully to the statements of all of the Heads of Delegation of the 57 OSCE …
By Ambassador Daniel B. Baer | 9 December, 2016 | Topics: Events, Former U.S. Ambassadors, Ukraine Crisis
Mind the GONGOs: How Government Organized NGOs Troll Europe's Largest Human Rights Conference
GONGOs are nothing more than the real-world equivalent of the internet troll armies that insecure, authoritarian, repressive regimes have unleashed on Twitter.
By Ambassador Daniel B. Baer | 30 September, 2016 | Topics: Civil Society and NGOs, Former U.S. Ambassadors, Human Rights
Keeping an International Eye on Ukraine
Keeping an International Eye on Ukraine Leaders should insist that Russian separatists in the east not obstruct cease-fire monitoring missions. Wall Street Journal August 16, 2016 Op-ed by Ambassador Daniel Baer For the third year in a row, August is proving a particularly deadly month in eastern Ukraine. Russian fighters, funds, weapons and equipment have kept the conflict …
By Ambassador Daniel B. Baer | 16 August, 2016 | Topics: Former U.S. Ambassadors
Democracy Defender Award: Ambassador Baer's Remarks
The voices of people like Oleksandra remind everyone that there is no alternative to continuing the fight for reform and for a stronger Ukraine.
By Ambassador Daniel B. Baer | 24 February, 2016 | Topics: Civil Society and NGOs, Former U.S. Ambassadors, Ukraine Crisis | Tags: Russia, Ukraine
European Security, Transatlantic Solidarity, and the "Moment" We're In
A talk by Ambassador Daniel B. Baer at the Austrian Institute for European and Security Policy | March 19, 2015 Thank you—thank you for that kind introduction—thank you for having me, and thank you to all of you for starting your Thursday evening with me. The last 2 years have turned out to be much …
By Ambassador Daniel B. Baer | 19 March, 2015 | Topics: Former U.S. Ambassadors
Joining Forces against Trafficking in Human Beings
Joining Forces against Trafficking in Human Beings On February 17th and 18th, the Council of Europe (currently chaired by Austria) and the OSCE (currently chaired by Switzerland) held a joint conference on combating trafficking in persons. The Council of Europe has played a key role in developing the legal infrastructure —including, notably, an international convention— …
By U.S. Mission OSCE | 19 February, 2014 | Topics: Former U.S. Ambassadors
Remarks at Swearing In Ceremony
As prepared for delivery by Daniel Brooks Baer September 10, 2013, Washington D.C. Thank you very much, Acting Assistant Secretary Zeya—the very best part about the last four years here at State has been the people I have come to know, adore, and be wowed by—and it has been a special joy to get to …
By U.S. Mission OSCE | 10 September, 2013 | Topics: Former U.S. Ambassadors