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(Baobab, Dead Rat Tree)
With a flared, muscular trunk and architectural, stubby branches, the baobab is a tree to admire in spacious landscapes. A slow-growing, deciduous tropical tree native to southern Sub-Saharan Africa, this succulent tree is characterized by a swollen trunk that often becomes hollow in order to store rainfall for sustenance. Interestingly, the wood of baobab is relatively soft and spongy and does not produce age rings, even though considered one of the longest-lived tree species on earth.
The medium...
(Desert Rose)
Desert rose is a heat-loving beauty with swollen "feet" or trunk flare. It is native to sub-Saharan Africa and Arabia and is a large perennial shrub to small tree with a wide swollen base which is sometimes buried underground. The ovate leaves are clustered on the ends of many twisted branches, most with no petiole. It is usually leafless during the cooler winter dry season. Grown for spectacular bell-shaped flowers with colors ranging from deep rose/red to pale pink which appear in summer in mass...
ADENIUM obesum 'Black Ruby'
Mark A. Miller
(Black Ruby Desert Rose, Desert Rose)
Desert rose is a hothouse baby with swollen "feet." It is native to sub-Saharan Africa and Arabia and is a large perennial shrub to small tree with a much swollen base which is sometime buried underground. Grown for spectacular bell-shaped flowers, 'Black Ruby' blossoms have white centers, red petals with a very dark red or 'black' edge which appear in summer in mass and few scattered throughout the year. The ovate leaves are clustered on the ends of many twisted branches, most with no petiole. It...
ADONIS amurensis
(Amur Adonis, Fukuju-so, Ganjitsu-so)
The Greek God Adonis represents life, death, and rebirth much like this sweet spring ephemeral. A truly magical early season bloomer, the low-growing Amur adonis produces large, glossy, semi-double buttercups towards winter's end. The traditional Japanese name "Fukuju-so" translates to "good fortune, long lived plants". Another old Japanese name is "Ganjitsu-so", which means "New Year's Day plant", referring to its early bloom time. Wild specimens naturally exist along open grassy slopes or wooded...
ADONIS annua
(Autumn Adonis, Pheasant's Eye)
Small, scarlet buttercups are the glory of the annual pheasant's eye. A wildflower of field and meadow, natural populations exist on calcareous soils across much of Europe, the Mediterranean, North Africa and western Asia. Each bloom has very dark anthers giving the appearance of a bird's or pheasant's eye. Flowering occurs from late spring to midsummer.
Seeds germinate in late winter or spring, and plants have very finely dissected ferny foliage that's pale or bright green. Small red flowers...
(Winter Pheasant's Eye)
Similar to the Asian Adonis amurensis but larger overall and better adapted to drought, winter pheasant's eye also has a broader area of distribution existing across much of Eurasia. In the wild, this spring ephemeral inhabits dry fields, roadsides and montane grasslands. Its golden flowers light up the landscape in late winter or spring and disappear by late spring. Occasionally, plants escape from cultivation; wild populations are known to exist in New York State's Westchester County.
Rising...
AECHMEA 'Big Harv'
(Aechmea, Big Harv Aechmea, Big Harv Bromeliad)
A large bromeliad for the tropical landscape, 'Big Harv' has light green and coppery foliage and produces a tall, branched, yellow and red flower spike in summertime. It is an evergreen, frost-tender perennial bromeliad that forms an upright rosette of leaves with a bold, coarse visual texture. It is usually grown in the soil but can be wedged among rocks. This hybrid was developed by Bullis Bromeliads of Princeton, Florida.
The long, rigid strappy leaves are a light green with coppery bronze...
AECHMEA 'Patricia'
(Aechmea, Patricia Aechmea, Patricia Bromeliad)
A large bromeliad for the tropical landscape, 'Patricia' has handsome evergreen foliage and brilliantly hued flowers. Developed by Bullis Bromeliads of Homestead, Florida, this frost-tender perennial forms an bold upright rosette of arching, broadly strap-shaped leaves. The leathery, light olive-green leaves have hints of silver and blushes of dark red-copper, particularly in cool conditions. Their edges are lined in tiny red lacerating spines. The leaf bases form a water-collecting "cup" at the...
AECHMEA fasciata
Carol Cloud Bailey
(Aechmea , Bromeliad, Urn Plant, Vase Plant)
Urn plant is a tree-dwelling tropical bromeliad native to Brazil. In its native habitat it lives under the rain forest canopy where it clings to tree branches and trunks. Plant enthusiasts grow it for its ornamental leaves and long-lasting pink blooms.
The huge, lance-shaped leaves of this Aechmea are gray green and silver with subtle horizontal stripes and spiny edges. They are bowed and often curve downward as they lengthen. Each plant produces one very long-lasting flower spike...
AEGOPODIUM podagraria
Russell Stafford
(Bishop's Goutweed)
Bishop's Goutweed is a fast-spreading Eurasian groundcover that has become naturalized across the whole of North America. It spreads via rhizomes (rooting underground stems) and has green compound leaves with three to nine leaflets. The equally weedy garden variety, 'Variegatum', is the most common form in cultivation and has leaves mottled with ivory.
In mid-spring to summer, goutweed produces umbels of tiny white flowers that are insect-pollinated and produce lots of brown seeds that spread...


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Stanford scientists develop new method to faster – and more accurately – find antigens that trigger specific immune cells
Their approach, which mimics the physical forces exerted by immune cells as they crawl over host cells, could help scientists develop more effective cancer immunotherapies.
By Rebecca McClellan
A cell's secrets can be divulged by its surface, decorated with tens to hundreds of thousands of molecules that help immune cells determine friend from foe. Some of those protruding molecules are antigens that trigger the immune system to attack, but it can be difficult for scientists to identify those antigens, which often vary across individuals, in the molecular forest.
The microwells in each experiment, seen in this micrograph by the black outlines, were loaded with spherical beads (the large grey circle in each well), and T cells (the smaller circles adhering to some of the beads). (Image credit: Yinnian Feng)
A team of Stanford scientists led by Polly Fordyce, an Institute Scholar at Sarafan ChEM-H, has developed a new method to faster and more accurately predict which antigens will lead to a strong immune response. Their approach, which was reported in Nature Methods on Sept. 5, could help scientists develop more effective cancer immunotherapies.
T cells, a class of immune cells, crawl along and squish past other cells as they patrol the body, using T cell receptors to molecularly read peptides, or short pieces of proteins – which are cradled within larger proteins called major histocompatibility complexes (pMHCs) that project from cell surfaces. Healthy host cells display an array of pMHCs that do not trigger an immune response, but once T cells recognize disease-indicating peptides, they become activated to find and kill cells bearing these foreign signatures. Understanding how T cells sensitively distinguish these antigenic peptides from host peptides to avoid mistakenly killing host cells has long been a mystery.
"A T cell can detect a single antigenic peptide amongst a sea of 10,000 or 100,000 non-antigenic peptides being displayed on cell surfaces," said Fordyce, assistant professor of bioengineering and of genetics.
The key to selectivity is in the T cell crawl. T cells' sliding puts stress on the bonds between receptors and peptides, and in most cases, that extra stress is enough to break that bond. But sometimes, it has the opposite effect. Chris Garcia, co-author of the study and professor of molecular and cellular physiology and of structural biology, and others had already shown that the most antigenic peptides are those whose interactions with T cell receptors grow stronger in response to sliding.
"It's kind of like a Chinese finger trap," said Fordyce. "When you pull a bit at the receptor-antigen interaction, the binding actually lasts longer."
Cellular mimicry
Identifying the best antigen-receptor pairs requires simultaneously applying that sliding, or shear, force between a peptide and a T cell and measuring T cell activation, ideally thousands of times to get repeatable data for many possible peptide/T cell receptor pairs. But existing methods are time-intensive and can result in measuring only one peptide with hundreds of T cells in a day.
The study's first author, postdoctoral scholar Yinnian Feng, developed a trick that allows the team to measure 20 unique peptides interacting with thousands of T cells in less than five hours.
To make a simplified system that mimics cells with dangling peptides, they constructed small spherical beads from a material that expands upon heating and attached a few molecules of a given peptide-studded pMHC to their surfaces. After depositing a T cell atop each bead and waiting long enough for receptors to bind to the peptides, they then very slightly heated the bead. The bead's expansion increases the distance between tether points, and the corresponding stretching of the T cell mimics the force it would experience sliding along cells in the body. After exerting that force, the team then measured how active the T cells were.
They could do hundreds of individual experiments in parallel by using beads that are each labeled with a unique color, making it possible to track multiple different pMHCs. They took two sets of pictures tiling across each slide after each run: one set that tells them which pMHC a given bead is displaying and another that tells them how active each T cell atop that bead is. Cross-referencing those images tells them which antigens led to the strongest T cell responses.
In this demonstration of their platform, the team showed, with 21 unique peptides, that their results confirmed known activating and non-activating peptides for one T cell receptor and uncovered a previously unknown antigen that induced a strong T cell response. Working with the Garcia lab, they have also already begun to address a challenge in immunotherapy: the T cell receptors that form the highest affinity interactions with antigens in the lab are often also activated by non-antigenic peptides in the body, a dangerous side effect that leads to the killing of healthy cells. Using their technology, the team characterized T cell receptors engineered to specifically recognize tumor antigens without off-target reactivity. In future work, they plan to build libraries of over 1,000 peptides to uncover novel antigens.
They hope that this approach, which is quick and requires few cells, or an optimized form of it could one day be used to improve personalized immunotherapies.
"This platform can help improve efforts to engineer T cells that specifically target cancer cells, as well as determine which antigens are capable of potently activating a patient's own T cells to more effectively target cancer cells," said Fordyce.
Fordyce is a member of Stanford Bio-X, SPARK, and the Wu Tsai Neurosciences Institute, and is a Chan Zuckerberg Biohub investigator. Garcia is a member of Stanford Bio-X, the Stanford Cancer Institute, the Wu Tsai Neurosciences Institute, and a Howard Hughes Medical Institute investigator.
Xiang Zhao and Adam K. White are also authors of the paper.
The work was funded by a Stanford Bio-X Interdisciplinary Initiatives seed grant and the National Institutes of Health.

redpajama_set_name: RedPajamaCommonCrawl