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Author(s):  
Kostiantyn V. Domasevitch ◽  
Ganna A. Senchyk

In the structure of the title compound [systematic name hexa-μ-oxido-1:2κ4 O:O;1:3κ4 O:O;1:4κ4 O:O-nonaphenyl-2κ3 C,3κ3 C,4κ3 C-triantimony(V)tellurium(VI)], [Sb3Te(C6H5)9O6], the hexaoxidotellurate(VI) ion is coordinated to three SbV ions via pairs of cis-positioned O atoms to form a discrete molecular unit. The TeVI and SbV central ions exhibit distorted octahedral [TeO6] and distorted trigonal–bipyramidal [SbC3O2] coordination geometries, respectively. The linking of these polyhedra, by sharing the dioxide edges, results in the Te-based octahedron having a mer-configuration. The packing of the molecules is dominated by C—H...O hydrogen bonding and weak dispersion forces, with a minor contribution from C—H...π bonds and π–π stacking interactions. According to the Hirshfeld surface analysis, the contributions of the H...H, H...C/C...H and H...O/O...H contacts are 58.0, 32.6 and 7.8%, respectively. The title structure provides a model for the bonding of triorganoantimony dications to octahedral oxoanions, and the observed doubly bridged motifs, Te(μ-O)2Sb, may find application in the functionalization of polyoxometalate species.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Amanda L. Gavin ◽  
Deli Huang ◽  
Tanya R. Blane ◽  
Therese C. Thinnes ◽  
Yusuke Murakami ◽  
...  

AbstractPhospholipase D3 (PLD3) and PLD4 polymorphisms have been associated with several important inflammatory diseases. Here, we show that PLD3 and PLD4 digest ssRNA in addition to ssDNA as reported previously. Moreover, Pld3−/−Pld4−/− mice accumulate small ssRNAs and develop spontaneous fatal hemophagocytic lymphohistiocytosis (HLH) characterized by inflammatory liver damage and overproduction of Interferon (IFN)-γ. Pathology is rescued in Unc93b13d/3dPld3−/−Pld4−/− mice, which lack all endosomal TLR signaling; genetic codeficiency or antibody blockade of TLR9 or TLR7 ameliorates disease less effectively, suggesting that both RNA and DNA sensing by TLRs contributes to inflammation. IFN-γ made a minor contribution to pathology. Elevated type I IFN and some other remaining perturbations in Unc93b13d/3dPld3−/−Pld4−/− mice requires STING (Tmem173). Our results show that PLD3 and PLD4 regulate both endosomal TLR and cytoplasmic/STING nucleic acid sensing pathways and have implications for the treatment of nucleic acid-driven inflammatory disease.


2021 ◽  
Vol 26 (2(78)) ◽  
pp. 89-100
Author(s):  
O. V. Buchko

Intermolecular interactions in the coordination compounds of cation-anionic type [Ni(phen)3][Ge(HCit)2]·2H2O (I), [Co(phen)3][Ge(HCit)2]⋅2H2O (II), [Co(H2O)2(phen)2]2[Ge(Cit)2]·4H2O (III) were characterized using Hirshfeld surface analysis. It was established that the biggest contribution in the Hirshfeld surface of anions have been made by the bonds H … В / О …Н (57,8 % (I), 59,6 % (II), 63,9 % (III)), H … H (28,2 % (I), 24,9 % (II), 31,4 % (III)). At the same time interactions C … H / Н … С are less significant (9,6 %, 11,2 % and 3,2 % for I, II, III, respectively). The calculated percentage contribution of different intermolecular interactions of cations in the crystals showed, that, unlike the anions, contacts H … Н (37,9 % (IА), 38,6 % (IB), 36,2 % (IIА и IIB), 38,8 % (III)) play dominating role, while contribution of H … В / О … Н is less (26,5 % (IA and IB), 28,3 % (IIA), 24,5 % (IIB), 26 2 % (III)). Furthermore, interactions C … H / Н … С are more significant than in anions (24,8 % (IА), 27,2 % (IB), 25,6 % (IIА), 26,2 % (IIB), 21,3 % (III). It is typical for cations to have С …С bonds (5,5 % in average) that give contribution less then 1 %. It was determined that voids volume in the crystals of compounds I–III is 751,74 (I), 778,21 (II) and 423,23 (III) Å3 and surface area is 1772,28 (I), 1821,36 (II) and 628,38 (III) Å2. The total volume of the voids (15 % in I, 15,7 %, in II, 22,4 % in III) testifies the lack of big cavities in the frames of the studied compounds. Thereby analysis of intermolecular interactions with the help of Hirshfeld surface analysis showed the dominating role of hydrogen bonds H … O / O …H and contacts H … H, and minor contribution of C … H / H … C and С … С bonds for all studied compounds. The absence of p-p stacking interactions between aromatic rings of 1,10-phenanthroline in the cations of complexes I–III was also pointed out.


2021 ◽  
Vol 18 (14) ◽  
pp. 4431-4444
Author(s):  
Michael P. Adams ◽  
Nina S. Atanasova ◽  
Svetlana Sofieva ◽  
Janne Ravantti ◽  
Aino Heikkinen ◽  
...  

Abstract. In order to effectively predict the formation of ice in clouds we need to know which subsets of aerosol particles are effective at nucleating ice, how they are distributed and where they are from. A large proportion of ice-nucleating particles (INPs) in many locations are likely of biological origin, and some INPs are extremely small, being just tens of nanometres in size. The identity and sources of such INPs are not well characterized. Here, we show that several different types of virus particles can nucleate ice, with up to about 1 in 20 million virus particles able to nucleate ice at −20 ∘C. In terms of the impact on cloud glaciation, the ice-nucleating ability (the fraction which are ice nucleation active as a function of temperature) taken together with typical virus particle concentrations in the atmosphere leads to the conclusion that virus particles make a minor contribution to the atmospheric ice-nucleating particle population in the terrestrial-influenced atmosphere. However, they cannot be ruled out as being important in the remote marine atmosphere. It is striking that virus particles have an ice-nucleating activity, and further work should be done to explore other types of viruses for both their ice-nucleating potential and to understand the mechanism by which viruses nucleate ice.


Oceans ◽  
2021 ◽  
Vol 2 (3) ◽  
pp. 489-507
Author(s):  
Stuart C. Painter

Vertical distributions of biogenic silica (bSi), particulate inorganic carbon (PIC) and key biomineral-forming phytoplankton indicate vertical zoning, or partitioning, during the late summer stratified period in the northeast Atlantic. Coccolithophores were generally more numerous in the surface mixed layer, whilst PIC concentrations were more homogenous with depth throughout the euphotic zone. Diatoms were notably more abundant and more diverse in the lower euphotic zone beneath the mixed layer in association with subsurface maxima in chlorophyll-a, bSi and oxygen concentrations. The four dominant coccolithophore species (Emiliania huxleyi, Gephyrocapsa muellerae, Syracosphera spp., and Rhabdosphaera clavigera) represented 78 ± 20% (range 31–100%) of the observed community across all sampled depths yet simultaneously contributed an average of only 13% to measured PIC pools. The diatom community, which was dominated by Pseudo-nitzschia spp. and by a species tentatively identified as Nanoneis longta, represented only ~1% of the bSi pool on average, with contributions increasing within the chlorophyll maximum. Despite a slow gradual deepening of the surface mixed layer in the period prior to observation, and adequate nutrient availability beneath the mixed layer, biomineral pools at this time consisted largely of detrital rather than cellular material.


2021 ◽  
Author(s):  
Iraj Daizadeh

In the United States (US), the Food and Drug Administration (FDA) regulates medical devices (MDs). Though not a fair comparison but for illustrative purposes: a majority of medical products are MDs and not medicines (drug/biologics). Ignoring the minor contribution of drug/biologic-MD combinations, in 2020 alone, there were at least 5000 medical devices (roughly 50% of which were PMAs) registered versus that of 1600 for new or supplemental drug or biologics approvals (of which less than 10% were new). However, as discussed here, since the first recorded FDA MD guideline (February, 1975) until 2015, the number of MD guidelines have been historically stagnate (relative to those of medicines). Even when considering accommodations due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; COVID-19) pandemic and activity in digital health technologies, there still seems to be an upward trend. The question is why and for how long?


2021 ◽  
Vol 136 (3) ◽  
Author(s):  
S. A. Venikoudis ◽  
F. P. Fronimos

AbstractIn this paper, we investigate the inflationary phenomenology of an Einstein–Gauss–Bonnet theory with the extension of a logarithmic modified f(R) gravity, compatible with the GW170817 event. The main idea of our work is to study different results for an almost linear Ricci scalar through logarithmic corrections and examine whether such model is viable. First of all, the theoretical framework under slow-roll evolution of the scalar field is presented and also the formalism of the constant-roll evolution making predictions for the non-Gaussianities of the models is developed, since the constant-roll evolution is known to enhance non-Gaussianities. As shown, the non-Gaussianities are of the order $${\mathcal {O}}\sim (10^{-1})$$ O ∼ ( 10 - 1 ) . Furthermore, the slow-roll indices and the observational indices of inflation are calculated for several models of interest. As demonstrated, the phenomenological viability of the models at hand is achieved for a wide range of the free parameters and the logarithmic term has a minor contribution to numerical calculations, as expected.


Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 384
Author(s):  
Andong Du ◽  
Anders E. W. Jarfors ◽  
Jinchuan Zheng ◽  
Kaikun Wang ◽  
Gegang Yu

The effect of lanthanum (La)+cerium (Ce) addition on the high-temperature strength of an aluminum (Al)–silicon (Si)–copper (Cu)–magnesium (Mg)–iron (Fe)–manganese (Mn) alloy was investigated. A great number of plate-like intermetallics, Al11(Ce, La)3- and blocky α-Al15(Fe, Mn)3Si2-precipitates, were observed. The results showed that the high-temperature mechanical properties depended strongly on the amount and morphology of the intermetallic phases formed. The precipitated tiny Al11(Ce, La)3 and α-Al15(Fe, Mn)3Si2 both contributed to the high-temperature mechanical properties, especially at 300 °C and 400 °C. The formation of coarse plate-like Al11(Ce, La)3, at the highest (Ce-La) additions, reduced the mechanical properties at (≤300) ℃ and improved the properties at 400 ℃. Analysis of the strengthening mechanisms revealed that the load-bearing mechanism was the main contributing mechanism with no contribution from thermal-expansion mismatch effects. Strain hardening had a minor contribution to the tensile strength at high-temperature.


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