Network Based Approach Estimating COVID-19 Spread Patterns

In this study, we construct a series of evolving epidemic networks by measuring the correlations of daily COVID-19 cases time series among 3,105 counties in the United States. Remarkably, through quantitative analysis of the spatial distribution of these entities in different networks, we identify four typical patterns of COVID-19 transmission in the United States from March 2020 to February 2023. The onsets and wanes of these patterns are closely associated with significant events in the COVID-19 timeline. Furthermore, we conduct in-depth qualitative and quantitative research on the spread of the epidemic at the county and state levels, tracing and analyzing the evolution and characteristics of specific propagation pathways. Overall, our research breaks away from traditional infectious disease models and provides a macroscopic perspective on the evolution in epidemic transmission patterns. This highlights the remarkable potential of utilizing complex network methods for macroscopic studies of infectious diseases.Comment: 13 pages, 5 figures. This is a preprint of the final versio

Drought Monitoring for 3 North American Case Studies Based on the North American Land Data Assimilation System (NLDAS)

Both NLDAS Phase 1 (1996-2007) and Phase 2 (1979-present) datasets have been evaluated against in situ observational datasets, and NLDAS forcings and outputs are used by a wide variety of users. Drought indices and drought monitoring from NLDAS were recently examined by Mo et al. (2010) and Sheffield et al. (2010). In this poster, we will present results analyzing NLDAS Phase 2 forcings and outputs for 3 North American Case studies being analyzed as part of the NOAA MAPP Drought Task Force: (1) Western US drought (1998- 2004); (2) plains/southeast US drought (2006-2007); and (3) Current Texas-Mexico drought (2011-). We will examine percentiles of soil moisture consistent with the NLDAS drought monitor

Yeast Golden Gate: Standardized Assembly of S. cerevisiae Transcriptional Units

BBF RFC 88 describes a new standard for the assembly of basic Saccharomyces cerevisiae transcriptional units (TUs) consisting of a promoter/5’untranslated region (UTR), open reading frame (ORF), and 3’UTR/terminator. Note that we use the term “promoter” here to refer to both the promoter and the 5’ UTR, which we currently define as a single part. Future iterations of this standard will incorporate subdivision of currently defined parts e.g. into promoter and 5’ UTR. The standard makes use of the type IIS restriction enzyme BsaI to generate standardized and user­‐defined ‘signature overhangs’, thus enabling directional and seamless TU assembly. RFC88 is supported by the Yeast Standardized Collection of Parts for Expression (SCoPE), a repository of subcloned and sequence verified parts compatible with this assembly standard. The Yeast SCoPE is currently populated by a large number of S. cerevisiae promoters and terminators that facilitate expression and characterization of non­‐native ORFs

Facile synthesis of Cu and Cu@Cu-Ni nanocubes and nanowires in hydrophobic solution in the presence of nickel and chloride ions

In this work, we report an example of the facile synthesis of methyl methacrylate/tert-butyl acrylate (MMA/tBA) gradient copolymers (poly(MMA-grad-tBA) using the Cu(0) and conventional ATRP ligands as catalysts in DMF solvent at 25 degrees C. Semi-batch copper(0)-mediated living radical copolymerization technique (Cu(0)-mediated LRP) was used for achieving the chain gradient microstructure of the resulting copolymers. We also compared copolymerizations with two different ATRP ligands at ambient temperature allowing control over the molecular weight and polydispersity with a quarter of catalyst concentration versus a conventional ATRP in dipolar protic solvent (i.e. DMF), while the reaction temperature up to 80 degrees C in a non-polar medium (i.e. toluene) in order to reach the above polymerization efficiency. The addition of a small amount of reducing agent (i.e. hydrazine hydrate) into the reaction system allows the reaction proceeding in the oxygen tolerant system without losing control and decreasing total conversion such as using the reagents without deoxygenating

Study on wound healing effect of low-carbon topical dressings with new green packaging

In order to verify the effect of the new green and low-carbon hydrogel dressing on promoting wound healing, this project applied a sodium alginate hydrogel dressing product containing Escherichia coli and taro toxin analgesic polypeptide (The specific ingredients of the dressing) to skin wounds in common rats. Effects of the hydrogel dressing on promoting skin wound healing was evaluated by observing the occurrence and frequency of behavioral changes in rats, observing wwhistological sections under a high-power microscope, changes in serum cytokine indicators, and Image J analysis of collagen fiber reconstruction ratios in tissue sections. Through comprehensive evaluation, it can be found that hydrogel dressing has analgesic, anti-inflammatory and anti-infection effects on rat wound surface, and acts on promoting wound healing, promoting the formation of new blood vessels in the damaged skin tissue area, promoting the growth of granulation tissue, and promoting the reconstruction of collagen fibers in wound tissue

Small RNA interference-mediated gene silencing of heparanase abolishes the invasion, metastasis and angiogenesis of gastric cancer cells

<p>Abstract</p> <p>Background</p> <p>Heparanase facilitates the invasion and metastasis of cancer cells, and is over-expressed in many kinds of malignancies. Our studies indicated that heparanase was frequently expressed in advanced gastric cancers. The aim of this study is to determine whether silencing of heparanase expression can abolish the malignant characteristics of gastric cancer cells.</p> <p>Methods</p> <p>Three heparanase-specific small interfering RNA (siRNAs) were designed, synthesized, and transfected into cultured gastric cancer cell line SGC-7901. Heparanase expression was measured by RT-PCR, real-time quantitative PCR and Western blot. Cell proliferation was detected by MTT colorimetry and colony formation assay. The <it>in vitro </it>invasion and metastasis of cancer cells were measured by cell adhesion assay, scratch assay and matrigel invasion assay. The angiogenesis capabilities of cancer cells were measured by tube formation of endothelial cells.</p> <p>Results</p> <p>Transfection of siRNA against 1496-1514 bp of encoding regions resulted in reduced expression of heparanase, which started at 24 hrs and lasted for 120 hrs post-transfection. The siRNA-mediated silencing of heparanase suppressed the cellular proliferation of SGC-7901 cells. In addition, the <it>in vitro </it>invasion and metastasis of cancer cells were attenuated after knock-down of heparanase. Moreover, transfection of heparanase-specific siRNA attenuated the <it>in vitro </it>angiogenesis of cancer cells in a dose-dependent manner.</p> <p>Conclusions</p> <p>These results demonstrated that gene silencing of heparanase can efficiently abolish the proliferation, invasion, metastasis and angiogenesis of human gastric cancer cells <it>in vitro</it>, suggesting that heparanase-specific siRNA is of potential values as a novel therapeutic agent for human gastric cancer.</p

Small RNAs Targeting Transcription Start Site Induce Heparanase Silencing through Interference with Transcription Initiation in Human Cancer Cells

Heparanase (HPA), an endo-h-D-glucuronidase that cleaves the heparan sulfate chain of heparan sulfate proteoglycans, is overexpressed in majority of human cancers. Recent evidence suggests that small interfering RNA (siRNA) induces transcriptional gene silencing (TGS) in human cells. In this study, transfection of siRNA against −9/+10 bp (siH3), but not −174/−155 bp (siH1) or −134/−115 bp (siH2) region relative to transcription start site (TSS) locating at 101 bp upstream of the translation start site, resulted in TGS of heparanase in human prostate cancer, bladder cancer, and gastric cancer cells in a sequence-specific manner. Methylation-specific PCR and bisulfite sequencing revealed no DNA methylation of CpG islands within heparanase promoter in siH3-transfected cells. The TGS of heparanase did not involve changes of epigenetic markers histone H3 lysine 9 dimethylation (H3K9me2), histone H3 lysine 27 trimethylation (H3K27me3) or active chromatin marker acetylated histone H3 (AcH3). The regulation of alternative splicing was not involved in siH3-mediated TGS. Instead, siH3 interfered with transcription initiation via decreasing the binding of both RNA polymerase II and transcription factor II B (TFIIB), but not the binding of transcription factors Sp1 or early growth response 1, on the heparanase promoter. Moreover, Argonaute 1 and Argonaute 2 facilitated the decreased binding of RNA polymerase II and TFIIB on heparanase promoter, and were necessary in siH3-induced TGS of heparanase. Stable transfection of the short hairpin RNA construct targeting heparanase TSS (−9/+10 bp) into cancer cells, resulted in decreased proliferation, invasion, metastasis and angiogenesis of cancer cells in vitro and in athymic mice models. These results suggest that small RNAs targeting TSS can induce TGS of heparanase via interference with transcription initiation, and significantly suppress the tumor growth, invasion, metastasis and angiogenesis of cancer cells