77 research outputs found
The Convergence of Trade and Environment and the Relative Role of WTO
The purpose of this thesis is to give a comprehensive explanation of the worldwide trade and environment conflicts and a thorough analysis of the trade and environment debate between trade specialists and environmentalists. After a general introduction of the origin of and the critical issues involved in the trade and environment debate, this thesis discusses the complicated relation between trade and environment on the basis of economic theory and empirical studies. Then it examines the resolution of specific trade and environment conflicts within a multilateral trading system and the relative role of WTO in accommodating environmental interest into the trade liberalization. At last it comes to its conclusion that there is no inherent conflict between trade liberalization and environmental protection and trade and environment should go hand in hand to achieve a sustainable development and the improvement of human welfare as a whole
The mediating role of resilience in the relationship between stress and life satisfaction among Chinese medical students: a cross-sectional study
Comparative Transcriptome Analysis Reveals Genetic Mechanisms of Sugarcane Aphid Resistance in Grain Sorghum
The sugarcane aphid, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae) (SCA), has become a major pest of grain sorghum since its appearance in the USA. Several grain sorghum parental lines are moderately resistant to the SCA. However, the molecular and genetic mechanisms underlying this resistance are poorly understood, which has constrained breeding for improved resistance. RNA-Seq was used to conduct transcriptomics analysis on a moderately resistant genotype (TAM428) and a susceptible genotype (Tx2737) to elucidate the molecular mechanisms underlying resistance. Differential expression analysis revealed differences in transcriptomic profile between the two genotypes at multiple time points after infestation by SCA. Six gene clusters had differential expression during SCA infestation. Gene ontology enrichment and cluster analysis of genes differentially expressed after SCA infestation revealed consistent upregulation of genes controlling protein and lipid binding, cellular catabolic processes, transcription initiation, and autophagy in the resistant genotype. Genes regulating responses to external stimuli and stress, cell communication, and transferase activities, were all upregulated in later stages of infestation. On the other hand, expression of genes controlling cell cycle and nuclear division were reduced after SCA infestation in the resistant genotype. These results indicate that different classes of genes, including stress response genes and transcription factors, are responsible for countering the physiological effects of SCA infestation in resistant sorghum plants
Operator radiation dose during trans-hepatic arterial chemoembolization: different patients’ positions via transradial or transfemoral access
PURPOSEThis study aimed to compare the radiation dose received by the operator among different patients’ positions via transradial access (TRA) or transfemoral access (TFA) during transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC).METHODSA total of 120 patients with HCC undergoing TACE for the first time between January and November 2019 were randomized into 4 groups with 30 patients in each group. In group A, patients were placed in the foot-first position with the left upper arm abducted, and TACE was performed via the left radial artery. In group B, patients were placed in the conventional headfirst position with the left hand placed at the left groin, and TACE was performed via the left radial artery. In group C, patients were placed in the conventional head-first position, and TACE was performed via the right radial artery. In group D, patients were placed in the conventional head-first position, and TACE was performed via the right femoral artery. Before each procedure, thermoluminescent dosimeters were taped at 7 different body parts of the operator and the radiation dose was measured and collected after the procedure. The normalized radiation dose was also calculated. Procedural parameters included radiation dose, fluoroscopy time (FT), dose–area product (DAP), and air kerma (AK) were recorded. Patients’ demographics, tumor baseline characteristics, radiation dose, and procedural parameters were compared between groups.RESULTSNo significant differences were found in patients’ demographics, tumor baseline characteristics, as well as in total FT, DAP, and AK. However, significant differences were found in the total radiation dose received by the operator and the doses on the pelvic cavity and the right wrist (P < .05). In group C, the radiation doses received on the pelvic cavity, the right wrist, and the total radiation doses were relatively higher. Significant differences were also found in the normalized radiation doses received by the operator on the thyroid, chest, left wrist, right wrist, and pelvic cavity, and the total normalized doses (all P < .05). Similarly, the radiation doses received by the operator at the aforementioned parts in group C were higher, while those in group A were lower.CONCLUSIONNo statistically significant differences were observed in the FT, DAP, and AK in TACE via TRA when patients were placed in different positions. However, TACE via the left TRA, with patients in the feet-first position, reduced the radiation dose received by the operator, thereby reducing the radiation risk
Picosecond electric-field-induced threshold switching in phase-change materials
Many chalcogenide glasses undergo a breakdown in electronic resistance above
a critical field strength. Known as threshold switching, this mechanism enables
field-induced crystallization in emerging phase-change memory. Purely
electronic as well as crystal nucleation assisted models have been employed to
explain the electronic breakdown. Here, picosecond electric pulses are used to
excite amorphous AgInSbTe. Field-dependent reversible
changes in conductivity and pulse-driven crystallization are observed. The
present results show that threshold switching can take place within the
electric pulse on sub-picosecond time-scales - faster than crystals can
nucleate. This supports purely electronic models of threshold switching and
reveals potential applications as an ultrafast electronic switch.Comment: 6 pages manuscript with 3 figures and 8 pages supplementary materia
Glycated Haemoglobin A1c Variability Score Elicits Kidney Function Decline in Chinese People Living with Type 2 Diabetes
Our aim was to investigate the association of glycated haemoglobin A1c (HbA1c) variability score (HVS) with estimated glomerular filtration rate (eGFR) slope in Chinese adults living with type 2 diabetes. This cohort study included adults with type 2 diabetes attending outpatient clinics between 2011 and 2019 from a large electronic medical record-based database of diabetes in China (WECODe). We estimated the individual-level visit-to-visit HbA1c variability using HVS, a proportion of changes in HbA1c of ≥0.5% (5.5 mmol/mol). We estimated the odds of people experiencing a rapid eGFR annual decline using a logistic regression and differences across HVS categories in the mean eGFR slope using a mixed-effect model. The analysis involved 2397 individuals and a median follow-up of 4.7 years. Compared with people with HVS ≤ 20%, those with HVS of 60% to 80% had 11% higher odds of experiencing rapid eGFR annual decline, with an extra eGFR decline of 0.93 mL/min/1.73 m(2) per year on average; those with HVS > 80% showed 26% higher odds of experiencing a rapid eGFR annual decline, with an extra decline of 1.83 mL/min/1.73 m(2) per year on average. Chinese adults with type 2 diabetes and HVS > 60% could experience a more rapid eGFR decline
One-stop stroke management platform reduces workflow times in patients receiving mechanical thrombectomy
Background and purposeClinical outcome in patients who received thrombectomy treatment is time-dependent. The purpose of this study was to evaluate the efficacy of the one-stop stroke management (OSSM) platform in reducing in-hospital workflow times in patients receiving thrombectomy compared with the traditional model.MethodsThe data of patients who received thrombectomy treatment through the OSSM platform and traditional protocol transshipment pathway were retrospectively analyzed and compared. The treatment-related time interval and the clinical outcome of the two groups were also assessed and compared. The primary efficacy endpoint was the time from door to groin puncture (DPT).ResultsThere were 196 patients in the OSSM group and 210 patients in the control group, in which they were treated by the traditional approach. The mean DPT was significantly shorter in the OSSM group than in the control group (76 vs. 122 min; P < 0.001). The percentages of good clinical outcomes at the 90-day time point of the two groups were comparable (P = 0.110). A total of 121 patients in the OSSM group and 124 patients in the control group arrived at the hospital within 360 min from symptom onset. The mean DPT and time from symptom onset to recanalization (ORT) were significantly shorter in the OSSM group than in the control group. Finally, a higher rate of good functional outcomes was achieved in the OSSM group than in the control group (53.71 vs. 40.32%; P = 0.036).ConclusionCompared to the traditional transfer model, the OSSM transfer model significantly reduced the in-hospital delay in patients with acute stroke receiving thrombectomy treatment. This novel model significantly improved the clinical outcomes of patients presenting within the first 6 h after symptom onset
Regulation of Rice Flowering Time and Seed Development
Rice is one of the most important cereal crops for the world population. Flowering time and seed development of rice are directly related to plant regional and ecological adaptions, and productive yield. In this dissertation, to gain knowledge of seed development in rice, the status of post-translational modifications (PTMs) in developing rice seeds was investigated. Numerous modified lysine sites in developing rice seeds were identified utilizing antibody-based affinity enrichment approaches and nano-HPLC/MS/MS analyses of acetylated, succinylated, crotonylated and 2-hydroxyisobutyrylated peptides. Functional annotation analyses indicated that a wide variety of vital biological processes were targeted by lysine PTMs. A number of modified histone and non-histone proteins were found to harbor multiple PTMs, and our findings showed that many modified histone sites were conserved across plant, human, and animal systems. Comprehensive analyses of lysine modification sites illustrated that the sites were highly sequence-specific for distinct motifs. Overall, this study provides a systematic analysis of lysine PTM proteome in plants, which will serve as the basis for future investigations of the regulatory mechanisms and functions of lysine PTMs. The mechanisms of flowering time variances in response to different photoperiods were further studied in the rice mutant, HSS. QTL-seq analysis identified a major effect on chromosome 6 responsible for the phenotypic divergence between Nipponbare (wild-type) and HSS rice. Sequence and mRNA expression analyses confirmed that allelic variants of Hd1 make HSS plants less sensitive to photoperiod by altering expression level of Hd3a. Diurnal expression pattern analyses revealed that DTH8 transcripts were largely affected by Hd1 expression level in both LD and SD. This result suggested that Hd1 may able to regulate DTH8 and DTH8-Hd1 complex abundance in response to day length in rice flowering time regulation. In addition, we discussed the functions of PTMs in flowering time regulation in rice
Influence of Scanning Speed on the Microstructure and Wear Resistance of Laser Alloying Coatings on Ti-6Al-4V Substrate
Laser alloying has attracted significant attentions due to the advantages of high processing precision, good controllability and low heat effects on the substrate. However, the complexity of laser alloying requires further attentions on its processing parameters. This study aims at improving the wear resistance of the Ti-6Al-4V substrate by means of laser surface alloying with Ni-coated graphite (G@Ni). The effect of laser scanning speed is explored. The result suggests that the coating has a high surface quality and excellent metallurgical bonding with the substrate. NiTi and NiTi2 have a eutectic microstructure as well as in the TiC ceramic-reinforced phase as dendrites distribute in the γ-Ni matrix of the coatings. At higher scanning speeds, the lower energy density and shorter existence time of the molten pool refines the microstructure of the coating, improving its microhardness. At the scanning speed of 15 mm/s, the coating has the lowest wear weight loss due to its high microhardness and dense structure. This paper explores the influence of scanning speed on the microstructure and properties of the coatings, expanding the application of laser alloying on the surface modification of Ti-6Al-4V alloys
Predicting transcriptional responses to cold stress across plant species
Although genome-sequence assemblies are available for a growing number of plant species, gene-expression responses to stimuli have been cataloged for only a subset of these species. Many genes show altered transcription patterns in response to abiotic stresses. However, orthologous genes in related species often exhibit different responses to a given stress. Accordingly, data on the regulation of gene expression in one species are not reliable predictors of orthologous gene responses in a related species. Here, we trained a supervised classification model to identify genes that transcriptionally respond to cold stress. A model trained with only features calculated directly from genome assemblies exhibited only modest decreases in performance relative to models trained by using genomic, chromatin, and evolution/ diversity features. Models trained with data from one species successfully predicted which genes would respond to cold stress in other related species. Cross-species predictions remained accurate when training was performed in cold-sensitive species and predictions were performed in cold-tolerant species and vice versa. Models trained with data on gene expression in multiple species provided at least equivalent performance to models trained and tested in a single species and outperformed single-species models in cross-species prediction. These results suggest that classifiers trained on stress data from well-studied species may suffice for predicting gene-expression patterns in related, less-studied species with sequenced genomes
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