Comparative study on occurrence of class A and class Cβ-lactamase genes and their co-occurrence in Indian Enterobacteriaceae during years 2009 and 2010

Objective:To determine the occurrence of class A and class Cβ-Iactamase genes and their cooccurrence in Indian Enterobacteriaceae.Methods:52 third generation cephalosporin resistant isolates were phenotypically detected by combination disk method and screened by PCR to identify class A and class C typeβ-lactamase genes.Results:Of the 52 isolates,94.2%（49） were found harboring any of the bla?,blaCTX-M,blaSHV and blaTEM were present in 82.6%（43/52）, 59.6%（31/52）,and 42.3%（22/52） isolates,respectively.Of the 49 ESBL positive isolates 57.1% （28/49） showed co-occurrence of blaampCwith bla?.On the contrary,the collection from 2009 showed their co-occurrence in 81.4%isolates.Conclusions:The comparative study shows a downward trend for co-existence of bla? with blaampC from 2009 to 2010.Further large scale studies are needed to address the co-occurrence of class A and class Cβ-lactamases in India and the resistance trend occurring over a period of time.

基于C-STEAM理念下的《莆仙戏鼓课间操》实践探究

推动中华优秀传统文化进中小学课堂是落实党和国家立德树人根本任务的重要途径。C-STEAM教育旨在深刻挖掘文化内涵,创建项目式教学模式,在中小学校中弘扬与传承中华民族优秀的文化遗产,全面培养学生综合能力和必备技能。基于C-STEAM发展过程及特征。以《莆仙戏鼓课间操》为例,探究面向文化传承的学科融合教育的育人价值与路径,构建系统合理的项目式教学模式,以期在中小学生中建立“更基础、更广泛、更深厚”的文化自信。

新城疫病毒ClassⅠ强毒株磷蛋白在细胞中的表达与定位

根据Class Ⅰ新城疫病毒分离株9a5b编码序列设计特异性引物扩增P蛋白基因，原核表达后利用纯化的蛋白免疫BALB／c小鼠制备单克隆抗体，经二次亚克隆后筛选N4株针对P蛋白的单克隆抗体，利用所得单抗进行P蛋白在细胞内定位分析，NDV9a5b株按5M．0．I感染量接种DF1单层细胞.

基于C-class和E-class的B-learning在高职英语教学中的应用研究

B-learning是传统课堂教学C-class和网络平台学习E-class混合互补的教学模式,体现了《大学英语课程要求》提出的英语教学模式改革精神。结合山东外贸职业学院目前正在进行的高职英语B-learning改革尝试,讨论了高职英语B-learning模式下的教学设计及其效果。

Utilization of Class C Fly Ash As A Raw Material for Manufacturing of Refractory Materials

There have been increasing efforts to utilize energy by-products （EBP） all over the world. In the Czech Re- public fly ash is usually used in ceramic technology, es- pecially in brick manufacturing and for ceramic tiles. The average production of EBP is about Ig million tons per year. The range of potential products, where EBP could be used, is very wide and energy by-products have become an important raw material source. In this paper the attention was focused on class C fly ash and its usage in field of refractory materials. Experimental works were carried out on mixtures with fly ash and clay. There were also tested batches for lightweight fireclay bricks. The maximal amount of CFA should be up to 50%.

Comparative Analysis of Rigid PVC Foam Reinforced with Class C and Class F Fly Ash

Fly ash particles are usually spherical and based on their chemical composition;they are categorized into two classes: C and F. This study compares the microstructural, mechanical and thermal properties of extruded rigid PVC foam composites reinforced with class C and class F fly ash. The mechanical properties: such as tensile and flexural strength of composites containing class C fly ash were superior to the composites containing class F fly ash particles. Composites containing 6 phr class C fly ash showed a 24% improvement in the tensile strength in comparison to a mere 0.5% increase in composites reinforced with class F fly ash. Similarly, the addition of 6 phr of class F fly ash to the PVC foam matrix resulted in a 5.74% decrease in the flexural strength, while incorporating the same amount of class C fly ash led to a 95% increase in flexural strength. The impact strength of the composites decreased as the amount of either type of fly ash increased in the composites indicating that fly ash particles improve the rigidity of the PVC foam composites. No significant changes were observed in the thermal properties of the composites containing either type of fly ash particles. However, the thermo-mechanical properties measured by DMA indicated a steep increase in the viscoelastic properties of composites reinforced with class C flyash. The microstructural properties studied by Scanning Electron Microscopy (SEM) confirmed that fly ash particles were mechanically interlocked in the PVC matrix with good interfacial interaction with the matrix. However, particle agglomeration and debonding was observed in composites reinforced with higher amounts of fly ash.

Lean body mass index is a marker of advanced tumor features in patients with hepatocellular carcinoma

BACKGROUND Obesity is an independent risk factor for the development of hepatocellular carcinoma(HCC)and may influence its outcomes.However,after diagnosis of HCC,like other malignancies,the obesity paradox may exist where higher body mass index(BMI)may in fact confer a survival benefit.This is frequently observed in patients with advanced HCC and cirrhosis,who often present late with advanced tumor features and cancer related weight loss.AIM To explore the relationship between BMI and survival in patients with cirrhosis and HCC.METHODS This is a retrospective cohort study of over 2500 patients diagnosed with HCC between 2009-2019 at two United States academic medical centers.Patient and tumor characteristics were extracted manually from medical records of each institutions'cancer registries.Patients were stratified according to BMI classes:<25 kg/m^(2)(lean),25-29.9 kg/m^(2)(overweight),and>30 kg/m^(2)(obese).Patient and tumor characteristics were compared according to BMI classification.We performed an overall survival analysis using Kaplan Meier by the three BMI classes and after adjusting for Milan criteria.A multivariable Cox regression model was then used to assess known risk factors for survival in patients with cirrhosis and HCC.RESULTS A total of 2548 patients with HCC were included in the analysis of which 11.2%(n=286)were classified as noncirrhotic.The three main BMI categories:Lean(n=754),overweight(n=861),and obese(n=933)represented 29.6%,33.8%,and 36.6%of the total population overall.Within each BMI class,the non-cirrhotic patients accounted for 15%(n=100),12%(n=94),and 11%(n=92),respectively.Underweight patients with a BMI<18.5 kg/m^(2)(n=52)were included in the lean cohort.Of the obese cohort,42%(n=396)had a BMI≥35 kg/m^(2).Out of 2262 patients with cirrhosis and HCC,654(29%)were lean,767(34%)were overweight,and 841(37%)were obese.The three BMI classes did not differ by age,MELD,or Child-Pugh class.Chronic hepatitis C was the dominant etiology in lean compared to the overweight and obese patients(71%,62%,49%,P<0.001).Lean patients had significantly larger tumors compared to the other two BMI classes(5.1 vs 4.2 vs 4.2 cm,P<0.001),were more likely outside Milan(56%vs 48%vs 47%,P<0.001),and less likely to undergo transplantation(9%vs 18%vs 18%,P<0.001).While both tumor size(P<0.0001)and elevated alpha fetoprotein(P<0.0001)were associated with worse survival by regression analysis,lean BMI was not(P=0.36).CONCLUSION Lean patients with cirrhosis and HCC present with larger tumors and are more often outside Milan criteria,reflecting cancer related cachexia from delayed diagnosis.Access to care for hepatitis C virus therapy and liver transplantation confer a survival benefit,but not overweight or obese BMI classifications.

Comment on review article:Chronic hepatitis C virus infection cascade of care in pediatric patients

An enhanced cascade of care should include a younger population,helping to achieve the goal of the World Health Organization with a focus on elimination in the pediatric population.Furthermore,enhanced screening and awareness efforts and continued education of health care providers will improve the outcomes of chronic hepatitis C virus(HCV)infection in the pediatric population.The present work discusses and comments on the topic"cascade of care in HCV chronic pediatric patients".

Utilization of Thermally Treated Flue Gas Desulfurization (FGD) Gypsum and Class-C Fly Ash (CFA) to Prepare CFA-Based Geopolymer

The feasibility of utilization of flue gas desulfurization （FGD） gypsum and Class-C fly ash （CFA） to prepare CFA-based geopolymer were studied. The results showed that geopolymer made from 90% CFA and 10% FGD gypsum （FGDG） which was thermally treated at 800 ℃ for 1 h obtained the better compressive strength of 37.0 MPa. The micro characteristics and structures of the geopolymer samples of CFA and CFA-FGDG were tested by XRD, FT-IR, and SEM-EDXA after these samples cured at 75 ℃ for 8 h followed by 23 ℃ for 28 d. Both the geopolymer samples of CFA and CFA-FGDG have significant asymmetric stretching of A1-O/Si-O bonds and Si-O-Si / Si-O-A1 bending band. In geopolymer sample of CFA-FGDG, a small quantity of lathy products probably being the ettringite wrapped over the spherical fly ash particle, and the concentration of sulfur is much more than that in geopolymer sample of CFA. It is indicated that FGD gypsum may react during alkali-activated and geopolymeric process.

A New Phasor Estimator for PMU Applications:P Class and M Class

Phasor measurement units(PMUs)are fundamental tools in the applications of modern power systems,where synchronized phasor estimations are needed.The accuracy and dynamic performance requirements for phasor,frequency,and rate of change of frequency(ROCOF)estimations are established in the IEEE Std.C37.118.1-2011 along with the IEEE Std.C37.118.1 a-2014,where two PMU performances are suggested:P class filters for applications requiring fast response and M class filters for applications requiring high rejection to aliased signals.In this paper,a methodology to design new phasor estimators that satisfy the P class and M class requirements in PMUs is presented.The proposed methodology is based on finite impulse response filters,brick-wall filters,and complex filter design concepts,where frequency range,time performance,harmonic rejection and out-of-band interference requirements are considered in its design.A comparative analysis using the reference model given by the IEEE Std.C37.118.1 is presented.The results show the effectiveness of the phasor estimators under steady-state and dynamic conditions according to the PMU standard,making them suitable tools for applications in power systems.

Novel Cascade Refrigeration Cycle for Cold Supply Chain of COVID-19 Vaccines at Ultra-Low Temperature -80°C Using Ethane (R170) Based Hydrocarbon Pair

Several media report highlight on that the pharmaceutical companies require ultra-low temperatures -80°C to transport and store its COVID-19 vaccines. This research presents the thermodynamic analysis on cascade refrigeration system (CRS) with several refrigerant pairs which are R32/R170, R123/R170, R134a/R170, R404A/R170, R407c/R170, R410/R170, and the hydrocarbon (HC) refrigerant pair Propane/Ethane, namely R290/R170. Besides, the results of R22/R170 pair, which is not recommended to be used due to phase out of R22 as per Montréal Protocol, are included as base case to compare the novel hydrocarbon pairs in CRS and the old trend of refrigerant pairs. Thermodynamic properties of all these pairs were investigated and compared under different intermediate temperature used in CRS heat exchanger, which thermally connected both the Low and High temperature cycles (LTC) and (HTC). By applying the first law of thermodynamics, the coefficients of performance (COPs) and the specific power consumptions (SPC) in kW/TR are presented and compared. In addition, by applying the second law of thermodynamics the exergetic efficiencies were estimated. The results reveal the promising opportunity of using the HC pair (R290/R170). The minimum SPC in kW/TR is recorded for the pair R123/R170. One the other hand, the highest exegetic efficiency values are observed to be 40%, 38%, and 35% for the pairs R123/R170, R290/R170, and R134/R170, respectively. This research concludes that the HC pair (R290/R170) is highly recommended for CRS applications either to transport the COVID-19 or store it in cold storage rooms in hospitals and clinics. All precautionary measures should be carefully applied in design and operation of HC pair (R290/R170) due to its flammability hazard.

The Comribution of the New Class C From Brazil to Deindustrialization and Increased Imports

This research analyzes the growth impacts promoted by C class in the process of the freezing of the Brazilian industry and increased imports. This emerging market, called class C, which is incorporated in part by the low-income segment, presents distinct characteristics and needs and for this precise reason eventually burdens the short-term production of Brazilian companies, which feel the need to opt for the importation of basic commodities, manufactured, and semi-manufactured goods, in order to maintain a market share and return on their investments. Although this fact is actually part of a trend of global economic transformation, here it is due to a number of irregular actions taken by the Brazilian government facing a short-term political need. Stemming from quantitative researches and qualitative data, this paper sought to learn more about the consumers＇ profile and draw up some recommendations for the organizations, in order to be better prepared to face this new demand. This paper also sought to know the actions already undertaken by a large cosmetics company, parts of whose products aim at class C.

Diversity and Frequencies of HLA Class I and Class II Genes of an East African Population

Human Leukocyte Antigens (HLAs) play an important role in host immune responses to infectious pathogens, and influence organ transplantation, cancer and autoimmune diseases. In this study we conducted a high resolution, sequence-based genotyping of HLA class I and class II genes of more than 2000 women from Kenya, eastern Tanzania and southern Uganda around Lake Victoria and analyzed their allele, phenotype and haplotype frequencies. A considerable genetic diversity was observed at both class I and II loci. A total of 79 HLA-A, 113 HLA-B, 53 HLA-C, 25 HLA-DPA1, 60 HLA-DPB1, 15 HLA-DQA1, 44 HLA-DQB1 and 38 HLA-DRB1 alleles have been identified. The most common class I alleles were A * 02:01:01 (10.90%), B * 58:02 (8.79%), and C * 06:02:01 (16.98%). The most common class II alleles were DPA1*01:03:01 (40.60%), DPB1 * 01:01:01 (23.45%), DQA1 * 01:02:01 (31.03%), DQB1 * 03:01:01 (21.79%), DRB1 * 11:01:02 (11.65%), DRB3 * 02:02:01 (31.65%), DRB4 * 01:01:01 (10.50%), and DRB5 * 01:01:01 (10.50%). Higher than expected homozygosity was observed at HLA-B (P = 0.022), DQA1 (P = 0.004), DQB1 (P = 0.023), and DRB1 (P = 0.0006) loci. The allele frequency distribution of this population is very similar to the ones observed in other sub-Saharan populations with the exception of lower frequencies of A * 23 (5.55% versus 11.21%) and DQA1 * 03 (4.79% versus 11.72%), and higher frequencies of DPB1 * 30 (2.26% versus 0.37%) and DRB1 * 11 (21.51% versus 15.89%). The knowledge of the diversity and allele/ phenotype frequencies of the HLA alleles of this east African population, can contribute to the understanding of how host genetic factors influence disease susceptibility and effective anti-retroviral treatment of HIV infections and future vaccine trials.

用VC访问Oracle操作大数据类型的高效方法

在数据库应用开发过程中,经常要处理大量的大数据类型(如图形、声音文件或带格式的大文本文件等),如何处理这些数据是开发人员所面临的1个难题。本文阐明了在VC中利用OO4O包含的OracleC++ClassLibrary提供的一些基本类库来处理大数据类型的1种高效方法,并以处理Longraw数据类型和基本数据类型为例进行了比较说明。

AmpC酶的研究进展

大部分肠杆菌属及铜绿假单胞菌可以产生染色体介导的AmpC酶而引起对第三代头孢菌素的耐药。在缺乏β-内酰胺类抗生素诱导剂时 ,阴沟肠杆菌、弗劳地枸橼酸杆菌、铜绿假单胞菌只产生少量的β-内酰胺酶 ,但在β-内酰胺类抗生素诱导剂存在时 ,AmpC酶的产量明显增加。然而 ,在缺乏调节基因ampR的大肠杆菌中 ,AmpC酶却不能被诱导。AmpC酶诱导调节的机理目前尚未完全阐明 ,但认为与ampR、ampE、ampG、ampD有关。最近 ,肺炎克雷白杆菌、大肠杆菌、产气肠杆菌、沙门菌中发现了质粒介导的AmpC酶 ,这些质粒介导的AmpC酶与阴沟肠杆菌、弗劳地枸橼酸杆菌及铜绿假单胞菌的AmpC酶的氨基酸序列具有同源性。

A Fully Integrated Low Power Transmitter in an 802.11b Transceiver System

A fully integrated low power transmitter for an IEEE 802. llb transceiver system is implemented in SMIC 0.18μm technology. The direct-conversion transmitter includes two Chebyshev I low pass filters,two PGAs,a SSB mixer, and a PA driver. The transmitter provides a gain control of 32dB in 3dB steps. The maximum output power is - 3.4dBm and the EVM is 6. 8%. The power consumption of the transmitter is only 57.6mW with a 1.8V power supply. The chip area of the transmitter is 1.6mm × 1.6mm.

利用Windows API函数构造C++类实现串行通信

根据面向对象的程序设计思想 ,通过对Win dows串行通信应用编程接口 (API)中部分数据结构和函数的封装 ,构造串行通信类CComm。该类向用户提供几个简单的接口函数 ,从而大大方便了Windows系统下串行通信的编程。