Archives, Room Use Only - TK6015.K56 1972

Archives, Room Use Only - TK140.D3 D38 1929

Archives, Room Use Only - T19.B35 1860

Archives, Room Use Only - TK6545.L4 M55 1925

Archives, Room Use Only - DK755.K34 1890

Archives, Room Use Only - T15.T56 1867

Archives, Room Use Only - TK5241.D76 1880b

Archives, Room Use Only - F908.W59 1869

Archives, Room Use Only - PS3539.A14 C52 1915

Archives, Room Use Only - E470.2.W55 1888

Archives, Room Use Only - T15.B3813 1846

Archives, Room Use Only - TK5743.G74 1915

Archives, Room Use Only - PN6268.T4 E44 1848

Archives, Room Use Only - UG590.S54 1838

Archives, Room Use Only - T223.Z1 K45 1924

The Hall of Famer is repaying the money after an audit of funds alleged that Mississippi officials improperly spent $94 million in federal money.

HTML5 standardizes the oninput event handler, which should be used to detect user input in JavaScript. Sure, you could use onkeydown or onkeyup instead, but those were never really designed for this particular use case, and it shows.

No-touch systems, infrastructure to work from home are some of the changes

Apparently inspired by how Kerala used umbrellas to ensure physical distancing, a residents welfare association at Sai Nagar in Thoraipakkam has reque

Residents of AGS Colony Phase Three in Mugaliwakkam are upset that a new crop of vegetable vendors have come from nowhere, and set up stalls on Mugali

SS Karthikeya walks out of his next venture

Final Olympic archery qualification event in June next year

The title hepta­nuclear alkoxido(oxido)vanadium(V) oxide cluster complex, [V7(C10H19O)O17(C18H24N2)3]·CH3CN, was obtained by the reaction of [V8O20(C18H24N2)4] with 4-tert-butyl­cyclo­hexa­nol (mixture of cis and trans) in a mixed CHCl3/CH3CN solvent. The complex has a V7O18N6 core with approximately Cs symmetry, which is composed of two VO4 tetra­hedra, two VO6 octa­hedra and three VO4N2 octa­hedra. In the crystal, these complexes are linked together by weak inter­molecular C—H⋯O hydrogen bonds between the 4,4'-di-tert-butyl-2,2'-bi­pyridine ligand and the V7O18N6 core, forming a one-dimensional network along the c-axis direction. Besides the complex, the asymmetric unit contains one CH3CN solvent mol­ecule. The contribution of other disordered solvent mol­ecules to the scattering was removed using the SQUEEZE option in PLATON [Spek (2015). Acta Cryst. C71, 9–18]. The unknown solvent mol­ecules are not considered in the chemical formula and other crystal data.

Single crystals of the m = 8 member of the low-dimensional monophosphate tungsten bronzes (PO2)4(WO3)2m family were grown by chemical vapour transport technique and the high crystalline quality obtained allowed a reinvestigation of the physical and structural properties. Resistivity measurements revealed three anomalies at TC1 = 258 K, TC2 = 245 K and TC3 = 140 K, never observed until now. Parallel X-ray diffraction investigations showed a specific signature associated with three structural transitions, i.e. the appearance of different sets of satellite reflections below TC1, TC2 and TC3. Several harmonics of intense satellite reflections were observed, reflecting the non-sinusoidal nature of the structural modulations and a strong electron–phonon coupling in the material. These transitions could be associated with the formation of three successive unconventional charge density wave states.

Current software tools for the automated building of models for macro­molecular X-ray crystal structures are capable of assembling high-quality models for ordered macromolecule and small-molecule scattering components with minimal or no user supervision. Many of these tools also incorporate robust functionality for modelling the ordered water molecules that are found in nearly all macromolecular crystal structures. However, no current tools focus on differentiating these ubiquitous water molecules from other frequently occurring multi-atom solvent species, such as sulfate, or the automated building of models for such species. PeakProbe has been developed specifically to address the need for such a tool. PeakProbe predicts likely solvent models for a given point (termed a `peak') in a structure based on analysis (`probing') of its local electron density and chemical environment. PeakProbe maps a total of 19 resolution-dependent features associated with electron density and two associated with the local chemical environment to a two-dimensional score space that is independent of resolution. Peaks are classified based on the relative frequencies with which four different classes of solvent (including water) are observed within a given region of this score space as determined by large-scale sampling of solvent models in the Protein Data Bank. Designed to classify peaks generated from difference density maxima, PeakProbe also incorporates functionality for identifying peaks associated with model errors or clusters of peaks likely to correspond to multi-atom solvent, and for the validation of existing solvent models using solvent-omit electron-density maps. When tasked with classifying peaks into one of four distinct solvent classes, PeakProbe achieves greater than 99% accuracy for both peaks derived directly from the atomic coordinates of existing solvent models and those based on difference density maxima. While the program is still under development, a fully functional version is publicly available. PeakProbe makes extensive use of cctbx libraries, and requires a PHENIX licence and an up-to-date phenix.python environment for execution.

Multi-slice simulations of electron diffraction by three-dimensional protein crystals have indicated that structure solution would be severely impeded by dynamical diffraction, especially when crystals are more than a few unit cells thick. In practice, however, dynamical diffraction turned out to be less of a problem than anticipated on the basis of these simulations. Here it is shown that two scattering phenomena, which are usually omitted from multi-slice simulations, reduce the dynamical effect: solvent scattering reduces the phase differences within the exit beam and inelastic scattering followed by elastic scattering results in diffusion of dynamical scattering out of Bragg peaks. Thus, these independent phenomena provide potential reasons for the apparent discrepancy between theory and practice in protein electron crystallography.

Rotation is a core crystallographic operation. Two sets of Cartesian coordinates of each point of a rotated object, those before and after rotation, are linearly related, and the coefficients of these linear combinations can be represented in matrix form. This 3 × 3 matrix is unique for all points and thus describes unambiguously a particular rotation. However, its nine elements are mutually dependent and are not interpretable in a straightforward way. To describe rotations by independent and comprehensible parameters, crystallographic software usually refers to Euler or to polar angles. In crystallography and cryo-electron microscopy, there exists a large choice of conventions, making direct comparison of rotation parameters difficult and sometimes confusing. The program py_convrot, written in Python, is a converter of parameters describing rotations. In particular, it deals with all possible choices of polar angles and with all kinds of Euler angles, including all choices of rotation axes and rotation directions. Using a menu, a user can build their own rotation parameterization; its action can be viewed with an interactive graphical tool, Demo. The tables in this article and the extended help pages of the program describe details of these parameterizations and the decomposition of rotation matrices into all types of parameters. The program allows orthogonalization conventions and symmetry operations to be taken into account. This makes the program and its supporting materials both an illustrative teaching material, especially for non-specialists in mathematics and computing, and a tool for practical use.

The Python-based program py_convrot is a universal converter of rigid-body rotation parameters. The program interactively illustrates the action of various rotation parameters and can be used both for teaching goals and for practical applications.

In this work, the mechanism of solvent-mediated desolvation transformation of lenvatinib mesylate (LM) was investigated. Two new solid forms of LM, a dimethyl sulfoxide (DMSO) solvate and an unsolvated form defined as form D, were discovered and characterized using powder X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, polarized light microscopy and Raman spectroscopy. To investigate the thermodynamic mechanism of solvent-mediated desolvation transformation (SMDT) from LM DMSO solvate to form D, solubilities of LM DMSO solvate and form D in binary solvent mixtures of DMSO and water at different water volume fractions and temperatures (293.15–323.15 K) were measured and correlated by non-random two liquids model. The solubility data were used to evaluate the thermodynamic driving force of the SMDT process from DMSO solvate to form D and the effect of the activities of water and DMSO on the transformation process. Raman spectroscopy was used to monitor in situ the solid phase compositions during the SMDT process from LM DMSO solvate to form D while the solution concentration was measured by the gravimetric method. The overall desolvation transformation experiments demonstrated that the SMDT process was controlled by the nucleation and growth of form D. Moreover, effects of operating factors on the SMDT process were studied and the results illustrated that water activity in solution was the paramount parameter in the SMDT process. Finally, a new SMDT mechanism was suggested and discussed.

The solvent-mediated desolvation process of newly discovered lenvatinib DMSO solvate to form II at different water volume fractions and temperatures was investigated. It is confirmed that the activity of water is the most important factor affecting the desolvation process: the desolvation process only occurs when the activity of water is greater than the activity of DMSO, and one new mechanism of solvent-mediated desolvation process was proposed.

Immunoglobulin E (IgE) plays a central role in the allergic response, in which cross-linking of allergen by Fc∊RI-bound IgE triggers mast cell and basophil degranulation and the release of inflammatory mediators. The high-affinity interaction between IgE and Fc∊RI is a long-standing target for therapeutic intervention in allergic disease. Omalizumab is a clinically approved anti-IgE monoclonal antibody that binds to free IgE, also with high affinity, preventing its interaction with Fc∊RI. All attempts to crystallize the pre-formed complex between the omalizumab Fab and the Fc region of IgE (IgE-Fc), to understand the structural basis for its mechanism of action, surprisingly failed. Instead, the Fab alone selectively crystallized in different crystal forms, but their structures revealed intermolecular Fab/Fab interactions that were clearly strong enough to disrupt the Fab/IgE-Fc complexes. Some of these interactions were common to other Fab crystal structures. Mutations were therefore designed to disrupt two recurring packing interactions observed in the omalizumab Fab crystal structures without interfering with the ability of the omalizumab Fab to recognize IgE-Fc; this led to the successful crystallization and subsequent structure determination of the Fab/IgE-Fc complex. The mutagenesis strategy adopted to achieve this result is applicable to other intractable Fab/antigen complexes or systems in which Fabs are used as crystallization chaperones.

Scientists and local dive operators first noticed coral bleaching in the waters surrounding Isla Colon, in Panama’s Bocas del Toro province in July. Smithsonian staff scientist Nancy Knowlton and colleagues documented an extensive bleaching event in late September.

The post Coral bleaching event caused by warming ocean waters is documented in Panama appeared first on Smithsonian Insider.

The crustaceans are much more effective when they fight together than when they fight alone, a process McKeon calls the Multiple Defender Effect. “It is a clear example of synergy, and one that underscores the importance of biodiversity in the ocean.”

The post Preventing home invasions means fighting side-by-side for coral-dwelling crabs and shrimp appeared first on Smithsonian Insider.

They observed that no plugs were ever formed during mating trials, but instead, females exposed to many males produced the amorphous plugs during the egg-laying process.

The post Female spiders produce mating plugs to prevent unwanted sex from males appeared first on Smithsonian Insider.

A new study by Florida State University and Smithsonian Institution biologists shows that bleaching events brought on by rising sea temperatures are having a detrimental […]

The post Study: Bleaching events impair long-term coral reproduction appeared first on Smithsonian Insider.

Most people think of black holes as giant vacuum cleaners sucking in everything that gets too close. But the supermassive black holes at the centers […]

The post Event Horizon Telescope Reveals Magnetic Fields at Milky Way’s Central Black Hole appeared first on Smithsonian Insider.

With over 138 million collection objects, 2.1 million library volumes, and 137,000 cubic feet of archives, the stories of how our collections have made their […]

The post Seventeen Objects for 170 Years (Happy Birthday to us!) appeared first on Smithsonian Insider.

This Secret Smithsonian Adventures series follows four middle schoolers as they foil events by two dastardly doers who try to dangerously change the true course […]

The post Secret Adventures: “Claws and Effect” appeared first on Smithsonian Insider.

Liza Botros MD., Manon C. A. Pronk PhD., Jenny Juschten MD., John Liddle, Sofia K. S. H. Morsing, Jaap D. van Buul PhD., Robert H. Bates, Pieter R. Tuinman MD. PhD., Jan S. M. van Bezu, Stephan Huveneers PhD., Harm Jan Bogaard MD. PhD., Victor W. M. van Hinsbergh PhD., Peter L. Hordijk PhD., and Jurjan Aman MD. PhD.

Aims: Endothelial barrier dysfunction leads to edema and vascular leak, carrying high morbidity and mortality. Previously, Abl kinase inhibition was shown to protect against vascular leak. Using the distinct inhibitory profiles of clinically available Abl kinase inhibitors, we aimed to provide a mechanistic basis for novel treatment strategies against vascular leakage syndromes.

Methods & Results: Bosutinib most potently protected against inflammation-induced endothelial barrier disruption. In vivo, bosutinib prevented LPS-induced alveolar protein extravasation in an acute lung injury mice model. Mechanistically, Mitogen-activated Protein 4 Kinase 4 (MAP4K4) was identified as important novel mediator of endothelial permeability, which signals via ezrin, radixin and moesin proteins to increase turnover of integrin-based focal adhesions. The combined inhibition of MAP4K4 and Arg by bosutinib preserved adherens junction integrity and reduced turnover of focal adhesions, which synergistically act to stabilize the endothelial barrier during inflammation.

Conclusion: MAP4K4 was identified as important regulator of endothelial barrier integrity, increasing focal adhesion turnover and disruption of cell-cell junctions during inflammation. Inhibiting both Arg and MAP4K4, the clinically available drug bosutinib may form a viable strategy against vascular leakage syndromes.

George Smith, a marine biologist at the Smithsonian Environmental Research Center, explains his work of finding ways to prevent invasive species from being released in Baltimore Harbor in the ballast water of large ships.

The post Preventing ballast-water invasions of alien species appeared first on Smithsonian Insider.

An interview with National Museum of the American Indian curator Paul Chaat Smith (Comanche).  From the Smithsonian’s National Museum of the American Indian exhibition “Americans.” The […]

The post The Invention of Thanksgiving appeared first on Smithsonian Insider.

Nearly 60 million years ago rainforests prospered at temperatures that were 3-5 degrees higher and at atmospheric carbon dioxide levels 2.5 times today’s levels.

The post Plant diversity in tropical forests increased during ancient global warming event appeared first on Smithsonian Insider.

The cationic cyclo­metallated iridium(III) complex [Ir(C9H7N2)2(C12H8N2)](PF6) has been synthesized and crystallized by the inter-diffusion method. It contains an unknown number of solvent mol­ecules and has a different space-group symmetry (C2/c) structure than its solvatomorph (P21/c).