769 research outputs found
Tetraaquabis(N,N-dimethylformamide-κO)zinc(II) bis[(2-{3-[2-(carboxylatomethoxy-κ2 O,O′)phenyl]pyrazol-1-yl-κN 2}acetato-κO)chloridozincate(II)]
The asymmetric unit of the title compound, [Zn(C3H7NO)2(H2O)4][Zn(C13H10N2O5)Cl]2, is composed of a single anion and half a cation. The ZnII atom in the monoanion has a distorted triganol–pyramidal geometry, being coordinated by three O atoms and one N atom from one 2-{3-[2-(carboxylatomethoxy)phenyl]pyrazol-1-yl}acetate ligand and one Cl atom. In the dication, the ZnII atom is located on an inversion center and is coordinated by six O atoms in a slightly distorted octahedral geometry. In the crystal, the ions are linked by O—H⋯O hydrogen bonds, forming a two-dimensional network lying parallel to the ab plane. There are also C—H⋯O and C—H⋯Cl interactions present, which lead to the formation of a three-dimensional structure
Effects of Shenlian Extracts () on Atherosclerosis by Inhibition of the Inflammatory Response
ObjectiveInflammation plays a critical role in atherosclerosis, and this inflammatory reaction is being intensively studied. Shenlian Extracts (), an active ingredient of Chinese medicinal herbs, is believed to have multiple therapeutic and preventive effects against human vascular diseases, including atherosclerosis. Our work investigated whether Shenlian Extracts serves as an anti-inflammatory agent during atherogenesis.MethodsWe established a model of atherosclerosis in rabbits using balloon angioplasty and a high cholesterol diet. The effects of Shenlian Extracts on vessel structure and inflammation were assessed by hematoxylin-eosin staining of the femoral artery, measurement of inflammation-related factors in serum or vascular tissue, and radioimmunoassay. Enzyme linked immunosorbent assays (ELISA), flow cytometry and western blots were also performed.ResultsWe show that oral pre-treatment with Shenlian Extracts suppressed the pathological changes associated with atherosclerosis and that graded doses of Shenlian Extracts reduced total serum levels of cholesterol (90, 180 and 360 mg/kg), triglyceride (180 and 360 mg/kg), and LDL-c (90, 180 mg/kg). Various doses of Shenlian Extracts reduced serum content of TNF-a (180 and 360 mg/kg), CRP (90, 180 and 360 mg/kg) and IL-8 (360 mg/kg) (P<0.05), but led to no significant changes in IL-1β levels. Treatment with Shenlian Extracts also significantly reduced VCAM-1 levels (90 and 360 mg/kg) and IGF-1 levels (90 and 180 mg/kg) in vascular tissue but had no significant effect on ICAM-1 and MCP-1 levels. Finally, Shenlian Extracts significantly reduced the abnormal expression of CD18 in monocytes in a dose-dependent manner.ConclusionThese results suggest that Shenlian Extracts may play a direct role in preventing and treating atherogenesis by inhibiting the inflammatory reaction, providing insights into the possible mechanism underlying the anti-atherosclerotic actions of Shenlian Extracts
Microsatellite and mitochondrial DNA analysis of the genetic structure of Chinese horseshoe crab (Tachypleus tridentatus) in southeast China coast
Chinese horseshoe crab (Tachypleus tridentatus) is a Xiphosura animal of significant commercial importance and in danger of extinction in China. To better estimate how genetic structure can be used to obtain a conservation perspective of the species, genetic variation was examined in nine locations covering its distributing range in the coast of Chinese mainland using ten nuclear microsatellite DNA loci and mitochondrial DNA control region (CR) sequences. Moderate levels of genetic diversity were detected (expected heterozygosity from microsatellites was 0.635, haplotype diversity from mitochondrial DNA was 0.800) as a whole. Significant genetic differentiation was detected only by mitochondrial DNA (FST = 0.0693, P < 0.01), while microsatellite markers indicated nuclear genetic homogeneity of these locations. Probably, nuclear genetic homogeneity was caused by outbreeding among different groups due to artificial transporting. Very weak genetic differentiation indicates that reintroduction programs of the movement and mixing of horseshoe crab from different locations will result in minimal negative genetic effects. Upon four management units were inferred from the results of CR analysis, accordingly four or more nature reserves should be established to conserve this endangered animal along the Chinese coast. Haplotype network pattern indicated that T. tridentatus population in Chinese coast has undergone historic population expansion and very recent historic population recession. Mismatch distributions analysis also revealed existence of historic demographic expansion.Keywords: Tachypleus tridentatus, microsatellites, mitochondrial DNA, population structure, genetic diversityAfrican Journal of Biotechnology Vol. 12(16), pp. 2088-209
The prevention and controlling strategies for Ventilator Associated Pneumonia in clinical nursing
目的 探讨呼吸机相关肺炎的预防及有效控制的相关措施。方法 通过对呼吸机相关肺炎的发病原因及其危害的综述,系统总结了当前临床上主要的控制措施。结果 口腔护理、侧卧位、正确有效的吸痰及注意手卫生是预防呼吸机相关肺炎的主要非药理相关方法。结论 呼吸机相关肺炎通过药理护理和非药理护理可防可控。Objective: To explore the prevention strategies for Ventilator Associated Pneumonia and effective ways to control it. Methods: Through reviewing the caution and its damage of Ventilator Associated Pneumonia, we systematically summarized the major control measures that used in clinic. Results: Oral care, backrest elevation, right tube suctioning processes and hand cleaning are the major no-drug prevention strategies for Ventilator Associated Pneumonia. Conclusion: Ventilator Associated Pneumonia can be prevented and controlled by drugs and no-drugs nursing
Parameter-Efficient Prompt Tuning Makes Generalized and Calibrated Neural Text Retrievers
Prompt tuning attempts to update few task-specific parameters in pre-trained
models. It has achieved comparable performance to fine-tuning of the full
parameter set on both language understanding and generation tasks. In this
work, we study the problem of prompt tuning for neural text retrievers. We
introduce parameter-efficient prompt tuning for text retrieval across
in-domain, cross-domain, and cross-topic settings. Through an extensive
analysis, we show that the strategy can mitigate the two issues --
parameter-inefficiency and weak generalizability -- faced by fine-tuning based
retrieval methods. Notably, it can significantly improve the out-of-domain
zero-shot generalization of the retrieval models. By updating only 0.1% of the
model parameters, the prompt tuning strategy can help retrieval models achieve
better generalization performance than traditional methods in which all
parameters are updated. Finally, to facilitate research on retrievers'
cross-topic generalizability, we curate and release an academic retrieval
dataset with 18K query-results pairs in 87 topics, making it the largest
topic-specific one to date
Two CYP82D Enzymes Function as Flavone Hydroxylases in the Biosynthesis of Root-Specific 4′-Deoxyflavones in Scutellaria baicalensis
Baicalein, wogonin, and their glycosides are major bioactive compounds found in the medicinal plant Scutellaria baicalensis Georgi. These flavones can induce apoptosis in a variety of cancer cell lines but have no effect on normal cells. Furthermore, they have many additional benefits for human health, such as anti-oxidant, antiviral, and liver-protective properties. Here, we report the isolation and characterization of two CYP450 enzymes, SbCYP82D1.1 and SbCYP82D2, which function as the flavone 6-hydroxylase (F6H) and flavone 8-hydroxylase (F8H), respectively, in S. baicalensis. SbCYP82D1.1 has broad substrate specificity for flavones such as chrysin and apigenin and is responsible for biosynthesis of baicalein and scutellarein in roots and aerial parts of S. baicalensis, respectively. When the expression of SbCYP82D1.1 is knocked down, baicalin and baicalein levels are reduced significantly while chrysin glycosides accumulate in hairy roots. SbCYP82D2 is an F8H with high substrate specificity, accepting only chrysin as its substrate to produce norwogonin, although minor 6-hydroxylation activity can also be detected. Phylogenetic analysis suggested that SbCYP82D2 might have evolved from SbCYP82D1.1 via gene duplication followed by neofunctionalization, whereby the ancestral F6H activity is partially retained in the derived SbCYP82D2. We report the characterization of two CYP450 enzymes, which 6- and 8-hydroxylate chrysin to form the 4′-deoxyflavone bioactives in roots of Scutellaria baicalensis. Like the main 4′-deoxyflavone enzymes, these decorating enzymes have evolved their functionalities by convergence with the more ubiquitous 4′-hydroxyflavone pathway enzymes. Key words: Scutellaria baicalensis; Huangqin; baicalein; wogonin; flavone 6-hydroxylase; flavone 8-hydroxylas
Depositing boron on Cu(111): Borophene or boride?
Large-area single-crystal surface structures were successfully prepared on
Cu(111) substrate with boron deposition, which is critical for prospective
applications. However, the proposed borophene structures do not match the
scanning tunneling microscopy (STM) results very well, while the proposed
copper boride is at odds with the traditional knowledge that ordered
copper-rich borides normally do not exist due to small difference in
electronegativity and large difference in atomic size. To clarify the
controversy and elucidate the formation mechanism of the unexpected copper
boride, we conducted systematic STM, X-ray photoelectron spectroscopy and
angle-resolved photoemission spectroscopy investigations, confirming the
synthesis of two-dimensional copper boride rather than borophene on Cu(111)
after boron deposition under ultrahigh vacuum. First-principles calculations
with defective surface models further indicate that boron atoms tend to react
with Cu atoms near terrace edges or defects, which in turn shapes the
intermediate structures of copper boride and leads to the formation of stable
Cu-B monolayer via large-scale surface reconstruction eventually.Comment: 15 pages, 4 figure
Tanshinone IIA attenuates ovalbumin-induced airway inflammation and hyperresponsiveness in a murine model of asthma
Objective(s): Tanshinone IIA (T. IIA), one of the most pharmacologically active components extracted from Salviae miltiorrhiza, has anti-inflammatory and antioxidant features. The aim of the present study is to investigate the benefit of T. IIA on asthma using a murine model of asthma induced by ovalbumin (OVA). Materials and Methods: Male BALB/c mice were used in the present study. The mice were sensitized by OVA intraperitoneal injection on days 0 and 14, and received aerosolized OVA challenge for 30 min daily on days 21-23Results: T. T. IIA (10 mg/kg twice daily) intraperitoneal injection was performed on days 18-23. Results: Treatment of T. IIA reduced the levels of interleukin (IL)-4, IL-5, and IL-13 in bronchoalveolar lavage fluid (BALF) (PConclusion: T. IIA inhibits OVA-induced airway inflammation and hyperresponsiveness. T. IIA is a potential therapeutic agent for asthma
GLM-130B: An Open Bilingual Pre-trained Model
We introduce GLM-130B, a bilingual (English and Chinese) pre-trained language
model with 130 billion parameters. It is an attempt to open-source a 100B-scale
model at least as good as GPT-3 (davinci) and unveil how models of such a scale
can be successfully pre-trained. Over the course of this effort, we face
numerous unexpected technical and engineering challenges, particularly on loss
spikes and divergence. In this paper, we introduce the training process of
GLM-130B including its design choices, training strategies for both efficiency
and stability, and engineering efforts. The resultant GLM-130B model offers
significant outperformance over GPT-3 175B (davinci) on a wide range of popular
English benchmarks while the performance advantage is not observed in OPT-175B
and BLOOM-176B. It also consistently and significantly outperforms ERNIE TITAN
3.0 260B -- the largest Chinese language model -- across related benchmarks.
Finally, we leverage a unique scaling property of GLM-130B to reach INT4
quantization without post training, with almost no performance loss, making it
the first among 100B-scale models and more importantly, allowing its effective
inference on 4RTX 3090 (24G) or 8RTX 2080 Ti (11G) GPUs, the
most affordable GPUs required for using 100B-scale models. The GLM-130B model
weights are publicly accessible and its code, training logs, related toolkit,
and lessons learned are open-sourced at
\url{https://github.com/THUDM/GLM-130B/}.Comment: Accepted to ICLR 202
- …