The response of an oxide crystal to the atmosphere can be personified as breathing-a dynamic equilibrium between O
gas and O
anions in the solid. We characterize the analogous defect reaction in an ...iodide double-perovskite semiconductor, Cs
SnI
. Here, I
gas is released from the crystal at room temperature, forming iodine vacancies. The iodine vacancy defect is a shallow electron donor and is therefore ionized at room temperature; thus, the loss of I
is accompanied by spontaneous
-type self-doping. Conversely, at high I
pressures, I
gas is resorbed by the perovskite, consuming excess electrons as I
is converted to 2I
. Halide mobility and irreversible halide loss or exchange reactions have been studied extensively in halide perovskites. However, the reversible exchange equilibrium between iodide and iodine 2I
↔ I
+ 2e
described here has often been overlooked in prior studies, though it is likely general to halide perovskites and operative near room temperature, even in the dark. An analysis of the 2I
/I
equilibrium thermodynamics and related transport kinetics in single crystals of Cs
SnI
therefore provides insight toward achieving stable composition and electronic properties in the large family of iodide perovskite semiconductors.
Preliminary results for the synthesis of two new adenophostin analogues incorporating 3″- and 4″-methylenecarboxylate surrogate groups are presented. The synthesis involves the preparation of 3″- and ...4″-methylenecarboxylate glucose derivatives by a radical allylation—oxidative cleavage approach, their conversion into thioglycoside precursors, and stereoselective glycosylation of a suitable adenosine derivative. The glycosylations proceeded with excellent stereoselectivity, only the α product was detected, and in good yields.
Enterobacteriaceae producing β-lactamases have spread rapidly worldwide and pose a serious threat to human-animal-environment interface. In this study, we present the presence of Salmonella enterica ...(1.3%) and commensal Escherichia coli (96.3%) isolated from 400 environmental fecal dairy cattle samples over 20 farms in Uganda. Among E. coli isolates, 21% were resistant to at least one antimicrobial tested and 7% exhibited multidrug resistance. Four E. coli isolates displayed extended-spectrum beta-lactamase (ESBL)-producing genes, including bla
(n = 2/4), bla
(n = 1/4), bla
(n = 1/4), and bla
(n = 2/4). Whole genome sequencing confirmed the presence of the plasmid-mediated quinolone resistance qnrS1 gene among three ESBL isolates. No statistically significant differences in seasonal prevalence for E. coli and S. enterica among dairy cattle sampling periods were observed. Furthermore, to our knowledge, this is the first report of E. coli carrying bla
, bla
, bla
, or qnrS1 isolated from dairy cattle in Uganda. We conclude that the presence of globally disseminated bla
and bla
warrants further study to prevent further spread. In addition, the presence of fluoroquinolone resistant ESBL-producing E. coli on dairy farms highlights the potential risk among the human-livestock-environment interaction. This study can be used as a baseline for implementation of a more robust national integrated surveillance system throughout Uganda.
Early treatment with vit-D ameliorated with impaired recruitment of eosinophils on the local inflammatory response in bronchoalveolar lavage fluid and lung tissue in pre-mature mice.
Pyranoid glycals of all configurations can be obtained from pentoses through an olefination−cyclization−elimination sequence. The elimination can be carried out with excellent yields under radical ...conditions or by using common reductive reagents such as Zn/Cu, TiCl4/LiAlH4, or lithium naphthalenide. The proposed method is appropriate for the synthesis of glycals with allo or gulo configurations because the cyclization step is more efficient for these substrates.
•An intelligent energy management system for underground metro stations is examined.•The assembly phase involves an environmental impact of 897.02 Eco-indicator’99 points.•The monitoring subsystem ...dominates the environmental impact.•Considering a 5–10-year lifespan, the impact ranges between 1963 and 3029 Eco-points.•The impact on resources is the largest, followed by human health and ecosystem quality.
This paper presents for the first time the results of a life cycle assessment study for an intelligent energy management system. We considered material acquisition, manufacturing, transportation, assembly, operation and maintenance stages. The results show that the assembly phase had an environmental impact of 897 Eco-indicator 99 points that was mainly due to the monitoring subsystem (87.80%). When the analysis was extended to cover the use phase, the environmental impact ranged from 1963 (useful life of 5years) to 3029 Eco-indicator 99 points (useful life of 10years). The environmental impact of the use stage was found to represent 54–70% of the total, whereas the assembly stage represented 46–30%. The maintenance phase contributed to a very small extent to the total environmental impact (less than 0.5%). In any case, the impact on resources was the largest (about 51%), whereas the human health damage category amounted to approximately 35% and the ecosystem quality damage category represented about 14% of the total impact.
Resident neural precursor cells (NPCs) have been reported for a number of adult tissues. Understanding their physiological function or, alternatively, their activation after tissue damage or in vitro ...manipulation remains an unsolved issue. Here, we investigated the source of human dermal NPCs in adult tissue. By following an unbiased, comprehensive approach employing cell-surface marker screening, cell separation, transcriptomic characterization, and in vivo fate analyses, we found that p75NTR+ precursors of human foreskin can be ascribed to the Schwann (CD56+) and perivascular (CD56−) cell lineages. Moreover, neural differentiation potential was restricted to the p75NTR+CD56+ Schwann cells and mediated by SOX2 expression levels. Double-positive NPCs were similarly obtained from human cardiospheres, indicating that this phenomenon might be widespread.
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•Human dermis-derived cultures show two types of SOX2+ cells: Schwann and perivascular•p75NTR+CD56+ Schwann cells are responsible for neural progeny•SOX2 expression levels regulate the neural competence of dermal precursors•p75NTR+CD56+ neural precursor cells similarly arise from human cardiospheres
In this article, Izeta and colleagues show that neural precursor cell (NPC) cultures from adult human dermis include two SOX2+ cell subpopulations (Schwann and perivascular), and neural progeny is derived only from Schwann cells in a process regulated by their SOX2 expression levels. NPCs similarly arise from human cardiospheres, potentially elucidating the origin of seemingly unrelated NPCs observed in multiple organs.
Abstract
A novel
P
‐stereogenic PNP
t
Bu,Ph
ruthenium complex has been synthesized and characterized enabling the asymmetric hydrogenation of a wide range of aromatic ketones with excellent catalytic ...activities (up to 98 % conversion) and good levels of enantiodiscrimination (up to 95 %
ee
).
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