228 research outputs found
Exploratory synthesis of new transition metal complexes with polychalcogenide ligands using conventional solution reactions and hydro(solvo)thermal techniques
Thesis (Ph. D.)--Michigan State University. Department of Chemistry, 1993Includes bibliographical reference
The Comparison of Information Systems Develop Trends between the Chinese Mainland and International
The aims of this research are two fold. First, it compares the research focus of Information Systems in Mainland China with that of the international IS research community. Second, the paper describes the main features and trend of IS research in Mainland China, and makes some suggestions as to some possible interesting research arena. The data are from twenty five academic journals in China and proceedings of international Information Systems conferences
Averaged Behavior Model of Current-Mode Buck Converters for Transient Power Noise Analysis
Accurate Evaluation and Simulation of Power Noise is Critical in the Development of Modern Electronic Devices. However, the Widely Used Target Impedance Fails to Predict the Low-Frequency Noise Generated in a Device Due to the Existence of the Dc–dc Converter, Whose Output Impedance Can Change under Different Loading Conditions. a Physical Circuit Model is Then Desired to Replicate the Behavior of a Voltage Regulator Module, and the Average Technique is an Efficient Method to Estimate the Noise of a Pulse Width-Modulated (PWM) Converter. with the Emergence of Converters with Adaptive On-Time (AOT) Controllers, More Complex Averaging Methods Are Required, But None of Them Supports Transient Simulation. a General, Efficient, and Accurate Modeling Technique is Presented in This Article, Whose Framework Supports Both Current-Mode PWM and AOT Controllers. in Addition, a Novel Two-Step Parameter Extraction Method is Proposed, Which Can Be Used to Evaluate the Equivalent Values of Internal Feedback Parameters of an Encrypted Simulation Model or from Measurement. the Modeling Method is Validated by Both Simulation and Measurement
Prognostic and recurrent significance of SII in patients with pancreatic head cancer undergoing pancreaticoduodenectomy
BackgroundTo investigate the clinical significance of preoperative inflammatory status in patients with pancreatic head carcinoma (PHC), we performed a single-center study to assess it.MethodWe studied a total of 164 patients with PHC undergoing PD surgery (with or without allogeneic venous replacement) from January 2018 to April 2022. Systemic immune-inflammation index (SII) was the most important peripheral immune index in predicting the prognosis according to XGBoost analysis. The optimal cutoff value of SII for OS was calculated according to Youden index based on the receiver operating characteristic (ROC) curve and the cohort was divided into Low SII group and High SII group. Demographic, clinical data, laboratory data, follow-up data variables were obtained and compared between the two groups. Kaplan-Meier curves, univariable and multivariable Cox regression models were used to determine the association between preoperative inflammation index, nutritional index and TNM staging system with OS and DFS respectively.ResultsThe median follow-up time was 16 months (IQR 23), and 41.4% of recurrences occurred within 1 year. The cutoff value of SII was 563, with a sensitivity of 70.3%, and a specificity of 60.7%. Peripheral immune status was different between the two groups. Patients in High SII group had higher PAR, NLR than those in Low SII group (P <0.01, <0.01, respectively), and lower PNI (P <0.01). Kaplan–Meier analysis showed significantly poorer OS and DFS (P < 0.001, <0.001, respectively) in patients with high SII. By using the multivariable Cox regression model, high SII (HR, 2.056; 95% CI, 1.082–3.905, P=0.028) was significant predictor of OS. Of these 68 high-risk patients who recurrence within one year, patients with widespread metastasis had lower SII and worse prognosis (P <0.01).ConclusionHigh SII was significantly associated with poor prognosis in patients with PHC. However, in patients who recurrence within one year, SII was lower in patients at TNM stage III. Thus, care needs to be taken to differentiate those high-risk patients
Epidemiological and clinical characteristics of COVID-19 patients in Nantong, China
Introduction: COVID-19 is a newly emerging life-threatening respiratory disease caused by a newly identified coronavirus SARS-CoV-2.
Methodology: We included 28 COVID-19 patients admitted to Nantong Third Hospital from January 23 to February 26, 2020. SARS-CoV-2 infection was confirmed using real-time RT-PCR. The demographic, epidemiological, clinical, laboratory parameters were obtained from each patient.
Results: The vast majority (71.4%) of confirmed COVID-19 patients were brought in from outside of the city, and all others had contact history with these confirmed cases. The median age of patients was 50 years old and half had underlying diseases. The most common symptoms at the onset of illness were fever (96.4%), cough (67.9%), and chilly (28.6%), and 75.0% patients had two or more symptoms. Increased erythrocyte sedimentation rate, serum ferritin and C-reactive protein levels, and reduced absolute counts of total lymphocytes and T lymphocyte subsets were observed among the patients. The vast majority (85.7%) of patients showed bilateral or unilateral pneumonia, and three symptomatic patients and one asymptomatic case did not show abnormalities in their CT image. Among the 28 admitted patients, 24 were discharged as of February 26, 2020, with an average hospital stay of 14.96 (±4.27) days, which was not significantly associated with the interval between the onset of symptoms and admission.
Conclusions: In the absence of specific antiviral drugs or a vaccine, quarantine or isolation is the most effective intervention strategy for preventing the spread of the virus. Adequate supportive medical care is crucial for good prognosis of COVID-19 patients
Quality of reporting on randomized controlled trials on recurrent spontaneous abortion in China
BACKGROUND: Despite increasing numbers of RCTs done in China, detailed information on the quality of Chinese RCTs is still missing. The aim of this study was to assess the reporting quality of RSA RCTs and to identify significant predictors of reporting quality. METHODS: A literature review was conducted with the aim of identifying published RCTs on RSA conducted in China. In order to rate the report quality, we scored 1 for the item of CONSORT 2010 if it was reported and 0 if it was not stated or unclear. An overall quality score (OQS) with a range of 0–15 and a key methodological index score (MIS) with a range of 0–3 were calculated for each trial. RESULTS: A total of 98 relevant RCTs were included in the final analysis. The median OQS was 7, with a minimum of 1 and maximum of 12. The general level of OQS was not high, especially among ‘sample size,’ ‘baseline data,’ ‘outcomes and estimation,’ and ‘ancillary analyses,’ all of which had a positive rate of less than 10%. The median MIS was 1 with a minimum of 0 and maximum of 1. ‘Allocation concealment,’ ‘blinding,’ and ‘intention-to-treat analysis’ were mentioned in 1 (1%), 1 (1%) and 69 (70%) of the studies, respectively. In univariate analysis, funding was the only factor associated with an increased OQS. Specifically, the mean OQS increased by approximately 1.52 for manuscripts supported by funding (95% CI: 0.12 – 2.92; p = 0.03). With regard to the MIS, no association was found for any variable. CONCLUSION: RCTs of RSA conducted in China need improvement in order to meet the level of “reporting quality” required by the CONSORT statement. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13063-015-0665-6) contains supplementary material, which is available to authorized users
The Bottleneck and Breaking through of Chinese Engineering Technology Initiative: Interview of Scientific Thought Historian Zhu Yazong
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