The Beijing University Student Movement in the Hundred Flowers Campaign in 1957

Student activism in twentieth-century China has been a widely researched subject since the 1989 Tiananmen protests. However, little is known about Beijing University student movement in the Hundred Flowers Campaign in 1957, especially in English language sources. Based on posters and speeches from the movement, as well as student memoirs, this study situates the movement in a historical framework, and specifically looks at repertoires, organizations, framings, political opportunities and constraints, and reflections of the movement

Determinants of Post-Secondary Education Attainment

This paper uses high school longitudinal dataset to address a central question: What are the factors determining whether a student decides to enroll in post-secondary education, particularly 4-year Bachelor’s degree programs? Employing a Probit empirical design, this study measures the probability of a student attending both post-secondary education and specifically Bachelorette programs when considering an array of student- and parent-specific independent variables. The results highlight the importance of family influence on a student’s PSE outcome, most notably parental expectation. Further analysis also indicates that students with PSE inclinations experience larger effects across all variables. The findings of this paper suggest policy-makers to focus on fostering a pro-PSE culture for low socioeconomic families at minority communities

Vasodilator Stimulated Phosphoprotein (VASP) Regulates Actin Polymerization and Contraction in Airway Smooth Muscle by a Vinculin-dependent Mechanism

Vasodilator-stimulated phosphoprotein (VASP) can catalyze actin polymerization by elongating actin filaments. The elongation mechanism involves VASP oligomerization and its binding to profilin, a G-actin chaperone. Actin polymerization is required for tension generation during the contraction of airway smooth muscle (ASM); however, the role of VASP in regulating actin dynamics in ASM is not known. We stimulated ASM cells and tissues with the contractile agonist acetylcholine (ACh) or the adenylyl cyclase activator, forskolin (FSK), a dilatory agent. ACh and FSK stimulated VASP Ser157 phosphorylation by different kinases. Inhibition of VASP Ser157 phosphorylation by expression of the mutant VASP S157A in ASM tissues suppressed VASP phosphorylation and membrane localization in response to ACh, and also inhibited contraction and actin polymerization. ACh but not FSK triggered the formation of VASP-VASP complexes as well as VASP-vinculin and VASP-profilin complexes at membrane sites. VASP-VASP complex formation and the interaction of VASP with vinculin and profilin were inhibited by expression of the inactive vinculin mutant, vinculin Y1065F, but VASP phosphorylation and membrane localization were unaffected. We conclude that VASP phosphorylation at Ser157 mediates its localization at the membrane, but that VASP Ser157 phosphorylation and membrane localization are not sufficient to activate its actin catalytic activity. The interaction of VASP with activated vinculin at membrane adhesion sites is a necessary prerequisite for VASP-mediated molecular processes necessary for actin polymerization. Our results show that VASP is a critical regulator of actin dynamics and tension generation during the contractile activation of ASM

Transportation and Distribution of Food Banks and Pantries

According to data from U.S. Department of Agriculture's report, Ohio had the third lowest food security across United States. To ease food insecurity, some non-profit, charitable organizations, such as Food Banks and Pantries, distribute food to those who have difficulty purchasing enough to avoid hunger. They act as food storage and distribution depots for smaller agencies in different locations. Although there are many agencies offering food, some people still do not have access to this food because of consumer's transportation constraints or the organization's distribution schedule. The purpose of this research is to identify factors related to food insecurity and propose a plan to reduce these problems. This is achieved through county-level regression analysis, from 2015, to investigate the relationship between food insecurity and other variables such as the number of low income population, total population of 2010, median family income, number of kids and seniors, poverty rate, and ethnicity. Based on these results, it will be easier for agencies to predict the future trend of people with food insecurity. A recent innovation in SNAP, which builds on the cooperation between local grocery stores and Amazon may help those with food insecurity. Findings from this research offer Food Banks and Pantries, government agencies, and local non-profit organizations more directions to alleviate food insecurity problems.No embargoAcademic Major: Accountin

MODELING AND OPTIMIZATION OF PROPPANT DISTRIBUTIONS IN MULTICLUSTER HYDRAULIC FRACTURE-NATURAL FRACTURE (HF–NF) NETWORKS

One of the foremost challenges with proppant transport in hydraulic and/or natural fractures within unconventional reservoirs is that the proppant particles do not remain in the suspension transport mode, deviating significantly from the suspension assumption shared by most existing models that allow particles to be represented by a continuous pseudo-fluid phase. The advantage of the CFD-DEM simulator used in this study is its proppant particle migration within a Lagrangian frame of reference, which enables the description of proppant transport in any transport mode. This coupled simulator can capture the complex interactions between the proppant particles, the carrier fluid, and the walls of the hydraulic and/or natural fractures. Such a knowledge-based tool can provide new insights that can be used to optimize the stimulation design, leading to better proppant placement and higher fracturing effectiveness — which ultimately leads to higher flowrates and improved hydrocarbon recovery. The first part of the study involves the development of a robust proppant-bridging criterion at the Hydraulic Fracture-Natural Fracture (HF-NF) interface. The simulation results are used with an image classification algorithm to create a reliable proppant bridging criterion obtained from a well-trained Artificial Neural Network (ANN). The ANN is subjected to a standard K-fold cross-validation and is tested against a large suite of "control" simulation results. The second part of the study focuses on optimizing the proppant distribution in a multi-cluster horizontal well system. The cumulative proppant distributions at each cluster are computed based on the number of representative particles entering each cluster at each timestep. A sensitivity analysis is performed using the key system parameters (cluster spacing, number of clusters, proppant size, and perforation width) and the results of these analyses are used to propose optimization strategies

A novel role for RhoA GTPase in the regulation of airway smooth muscle contraction

Recent studies have demonstrated a novel molecular mechanism for the regulation of airway smooth muscle (ASM) contraction by RhoA GTPase. In ASM tissues, both myosin light chain (MLC) phosphorylation and actin polymerization are required for active tension generation. RhoA inactivation dramatically suppresses agonist-induced tension development and completely inhibits agonist-induced actin polymerization, but only slightly reduces MLC phosphorylation. The inhibition of MLC phosphatase does not reverse the effects of RhoA inactivation on contraction or actin polymerization. Thus, RhoA regulates ASM contraction through its effects on actin polymerization rather than MLC phosphorylation. Contractile stimulation of ASM induces the recruitment and assembly of paxillin, vinculin, and focal adhesion kinase (FAK) into membrane adhesion complexes (adhesomes) that regulate actin polymerization by catalyzing the activation of cdc42 GTPase by the G-protein-coupled receptor kinase-interacting target (GIT) - p21-activated kinase (PAK) - PAK-interacting exchange factor (PIX) complex. Cdc42 is a necessary and specific activator of the actin filament nucleation activator, N-WASp. The recruitment and activation of paxillin, vinculin, and FAK is prevented by RhoA inactivation, thus preventing cdc42 and N-WASp activation. We conclude that RhoA regulates ASM contraction by catalyzing the assembly and activation of membrane adhesome signaling modules that regulate actin polymerization, and that the RhoA-mediated assembly of adhesome complexes is a fundamental step in the signal transduction process in response to a contractile agonist

Mechanisms of Hypoxic Regulation of Plasminogen Activator Inhibitor-1 Gene Expression in Keloid Fibroblasts

Keloids are an excessive accumulation of extracellular matrix. Although numerous studies have shown elevated plasminogen activator inhibitor-1 (PAI-1) levels in keloid fibroblasts compared with those of normal skin. Their specific mechanisms involved in the differential expression of PAI-1 in these cell types. In this study, the upregulation of PAI-1 expression is demonstrated in keloid tissues and their derived dermal fibroblasts, attesting to the persistence, if any, of fundamental differences between in vivo and in vitro paradigms. We further examined the mechanisms involved in hypoxia-induced regulation of PAI-1 gene in dermal fibroblast derived from keloid lesions and associated clinically normal peripheral skins from the same patient. Primary cultures were exposed to an environmental hypoxia or desferroxamine. We found that the hypoxia-induced elevation of PAI-1 gene appears to be regulated at both transcriptional and post-transcriptional levels in keloid fibroblasts. Furthermore, our results showed a consistent elevation of HIF-1α protein level in keloid tissues compared with their normal peripheral skin controls, implying a potential role as a biomarker for local skin hypoxia. Treatment with antisense oligonucleotides against hypoxia-inducible factor 1α (HIF-1α) led to the downregulation of steady-state levels of PAI-1 mRNA under both normoxic and hypoxic conditions. Conceivably, our results suggest that HIF-1α may be a novel therapeutic target to modulate the scar fibrosis process

Effect of BRCA1 R1325K mutation on proliferation and apoptosis of gallbladder cancer cells

Objective·To investigate the effects of breast cancer susceptibility gene 1 (BRCA1) R1325K mutation [arginine (R) to lysine (K) mutation at amino acid 1325] on the proliferation and apoptosis of gallbladder cancer cell lines GBC-SD and NOZ.Methods·BRCA1 wild-type overexpression lentivirus, BRCA1 R1325K mutation overexpression lentivirus, and negative control lentivirus were used to construct the stable transgenic strains of gallbladder carcinoma, cell lines GBC-SD and NOZ. The cells were divided into the control group without the target gene, the BRCA1 wild-type group, and the BRCA1 R1325K mutation group. The expression of target protein was verified by Western blotting. The BRCA1 R1325K mutant gallbladder cancer cells were treated with 20 μmol/L Olaparib, a BRCA1 mutation inhibitor. Gallbladder cancer cell lines were divided into the control group, the BRCA1 wild-type group, the BRCA1 R1325K mutation group, and the BRCA1 R1325K mutation+Olaparib group according to the target gene expression and whether or not the inhibitor was added. The effect of BRCA1 R1325K mutation on proliferation and clonogenesis ability of gallbladder cancer cell lines GBC-SD and NOZ was observed by CCK8 assay and clonogenesis assay, respectively. The effect of BRCA1 R1325K mutation on apoptosis of gallbladder cancer cell lines GBC-SD and NOZ was observed by TUNEL assay. The expressions of apoptosis-related proteins, cleaved PARP, Bcl-2 and Bax, were detected by Western blotting. The inhibitor Olaparib was used to treat the BRCA1 R1325K mutant gallbladder cancer cell lines GBC-SD and NOZ. The phenotypic changes (promoting proliferation, enhancing clonogenesis and inhibiting apoptosis) induced by BRCA1 R1325K mutation were tested in the presence of Olaparib to determine whether the changes could be reversed by the inhibitor.Results·The results of CCK8 assay and clonogenesis assay showed that BRCA1 R1325K mutation could promote the proliferation of gallbladder cancer cell lines GBC-SD and NOZ, and improve their clonal formation ability, compared with the control group and the BRCA1 wild-type group. Olaparib inhibited the proliferation of gallbladder cancer cell lines overexpressing BRCA1 R1325K mutation (P<0.05). Through TUNEL and Western blotting, it was found that overexpression of wild-type BRCA1 could induce the apoptosis of gallbladder cancer cell lines GBC-SD and NOZ, compared with the control group. Compared with the control group and the BRCA1 wild-type group, the BRCA1 R1325K mutation group had anti-apoptotic effect, in which the expression of apoptosis-inhibiting protein Bcl-2 increased and the expression of pro-apoptotic protein Bax decreased (P<0.05).Conclusion·BRCA1 R1325K mutation can promote the proliferation of GBC-SD and NOZ cell lines and inhibit their apoptosis

Mechanisms of Hypoxic Regulation of Plasminogen Activator Inhibitor-1 Gene Expression in Keloid Fibroblasts

Keloids are an excessive accumulation of extracellular matrix. Although numerous studies have shown elevated plasminogen activator inhibitor-1 (PAI-1) levels in keloid fibroblasts compared with those of normal skin. Their specific mechanisms involved in the differential expression of PAI-1 in these cell types. In this study, the upregulation of PAI-1 expression is demonstrated in keloid tissues and their derived dermal fibroblasts, attesting to the persistence, if any, of fundamental differences between in vivo and in vitro paradigms. We further examined the mechanisms involved in hypoxia-induced regulation of PAI-1 gene in dermal fibroblast derived from keloid lesions and associated clinically normal peripheral skins from the same patient. Primary cultures were exposed to an environmental hypoxia or desferroxamine. We found that the hypoxia-induced elevation of PAI-1 gene appears to be regulated at both transcriptional and post-transcriptional levels in keloid fibroblasts. Furthermore, our results showed a consistent elevation of HIF-1α protein level in keloid tissues compared with their normal peripheral skin controls, implying a potential role as a biomarker for local skin hypoxia. Treatment with antisense oligonucleotides against hypoxia-inducible factor 1α (HIF-1α) led to the downregulation of steady-state levels of PAI-1 mRNA under both normoxic and hypoxic conditions. Conceivably, our results suggest that HIF-1α may be a novel therapeutic target to modulate the scar fibrosis process

The sequencing and de novo assembly of the Larimichthys crocea genome using PacBio and Hi-C technologies.

Larimichthys crocea is an endemic marine fish in East Asia that belongs to Sciaenidae in Perciformes. L. crocea has now been recognized as an "iconic" marine fish species in China because not only is it a popular food fish in China, it is a representative victim of overfishing and still provides high value fish products supported by the modern large-scale mariculture industry. Here, we report a chromosome-level reference genome of L. crocea generated by employing the PacBio single molecule sequencing technique (SMRT) and high-throughput chromosome conformation capture (Hi-C) technologies. The genome sequences were assembled into 1,591 contigs with a total length of 723.86 Mb and a contig N50 length of 2.83 Mb. After chromosome-level scaffolding, 24 scaffolds were constructed with a total length of 668.67 Mb (92.48% of the total length). Genome annotation identified 23,657 protein-coding genes and 7262 ncRNAs. This highly accurate, chromosome-level reference genome of L. crocea provides an essential genome resource to support the development of genome-scale selective breeding and restocking strategies of L. crocea