Effect and mechanism of Irbesartan on occurrence of ventricular arrhythmias in rats with myocardial ischemia through connexin43(cx43)

Objective: To explore the effect and mechanism of angiotensin II receptor blockers-Irbesartan on occurrence of ventricular arrhythmias in rats with myocardial ischemia. Methods: Rats with embryonic cardiomyocytes-H9c2 were randomly divided into control group. ischemia group. Irbesartan group and Irbesartan+ischemia group. The cell viability of rats in each group was tested using MTT. Real-time PCR was employed to detect the expression of connexin43 (Cx43) mRNA and western blot to detect the expression of Cx43 and phosphorylated Cx43. SD rats were randomly divided into the sham-operation group (SO). myocardial infarction group (MI). Irbesartan group and MI+ Irbesartan group, with 10 rats in each group. HE staining was employed to observe the change in the pathomorpholouy of left ventricular tissue and TUNEL method to analyze the cell apoptosis in the tissue. The immunofluorescence was adopted to observe the expression and distribution of Cx43 in the left ventricular myocardium and study the change in the expression of Cx43 in the cardiac muscular tissue at mRNA and protein level. Results: The intervention of lrbesartan in the condition of ischemia indicated the significant decrease in the number of necrotic cells. The expression of Cx43 was significantly decreased under the culture of ischemia (P<0.05), but in the presence of Irbesartan, the expression of Cx43 was increased compared with the ischemia group (p<0.01). The results of WB assay showed the similar trend of change at mRNA level. There was the significant difference in the score of ventricular arerythmia between MI group and SO group (P<0.01). The incidence of ventricular tachycardia or ventricular fibrillation was significantly increased compared with the one in SO group (P<0.05). There was the significant difference in the overall score between MI+Irbesartan group and MI group (P<0.05). The expression of Cx43 in the cardiac muscular tissue in MI group was significantly decreased (P<0.01(US) SO group). But the expression of Cx43 was increased after the treatment with Irbesartan. Conclusions: Irbesartan can inhibit the injury of H9c2 cardiomyocytes and the decreased expression of Cx43 that are induced by the ischemic myocardial infarction. Irbesartan can also improve the reconstruction of Cx43 in rats with ischemic myocardium to inhibit the myocardial infarction-induced arrhythmias.

Advances of Metal-Organic Frameworks in Energy and Environmental Applications

Nowadays, energy shortage and environmental pollution issues are increasingly severe and urgent to be solved. The effective storage and use of environmentally friendly fuels and removal of harmful gases from the environment are great challenges and of great importance both for the environment protection and for human health. Porous met- al-organic frameworks （MOFs） are highly ordered crystalline materials formed by the self-assembly process of metal ions and organic ligands. Their good features such as ultrahigh porosity, large surface area, structural diversity and functionalities make them promising candidates for applications in energy and environmental fields. MOF thin films and MOF composites have also been investigated to further enhance the properties and introduce new func- tionalities. This review provides an overview of the synthesis methods of pristine MOFs, MOF thin films and MOF composites, and significant advances of MOFs in energy and environment applications such as energy storage （H2, CH4）, CO2 capture and separation, adsorption removal and sensing of harmful gases in the environment.

Gases emissions estimation and analysis by using carbon dioxide balance method in natural-ventilated dairy cow barns

Contaminated gases emissions from livestock industry are becoming one of the most significant contributors to the increasingly serious environmental pollution.To find a way to reduce gases emissions,it is essential to reveal the factors that can affect the gases emissions.In this study,the concentrations of typical gases(including ammonia(NH_(3)),carbon dioxide(CO_(2)),hydrogen sulfide(H_(2)S),and sulfur dioxide(SO_(2)))generated from naturally-ventilated dairy cow barns were detected through the sample-data method in Tianjin,northern China.Indoor environmental conditions,such as temperature(T)and relative humidity(RH),were measured simultaneously.After applying the carbon dioxide mass balance method,ammonia,hydrogen sulfide and sulfur dioxide emissions were determined.The correlation analysis and regression analysis between the climate condition and gas emissions were conducted to assess the data collected in dairy cow barns during the whole study period.There was a significant relationship between environmental conditions and gas emissions.NH3,H2S and SO_(2) emissions from the building are in the range of 0.98-2.36 g/LU·h,0-0.034 g/LU·h,and 0-0.069 g/LU·h,respectively.The numerical analysis shows that the NH3 emission is highly correlated with the temperature and relative humidity.The ventilation rate shows a positive correlation with all the three gases.

Healthy Urbanization:From Quantitative Growth to Qualitative Promotion–Adjustment on Emphasis of Urbanization Strategy

China is currently experiencing the dramatic process of rapid urbanization,and the issue of how to realize a healthy urbanization is such a hot topic that it attracts attention at various levels from the Central Government to the local governments,as well as in many fields from academic community to political circles.Around this issue,this article provides several related point of views from seven experts and scholars,in order to inspire the thoughts on the future of China’s urbanization.

Comparison of direct and indirect determinations of dynamic ventilation rate in a modern dairy free stall barn

Reliable estimation of the ventilation rate(VR)in intensive livestock buildings is necessary for studying building environmental control strategies and predicting indoor air quality and air emissions.As direct air exchange measurements are time-consuming and expensive,it is environmentally inefficient to measure livestock building VR continuously in practice.Hence,indirect VR estimation methods have been widely used in modelling environmental control and air emissions,and also to measure airflow in the field.The accuracy of indirect measurement methods needs to be evaluated by comparing with direct measurements.In this study,the direct and indirect methods of determining hourly and daily mean VRs were applied to a mechanically-ventilated dairy free stall barn monitored by the 24-month National Air Emissions Monitoring Study.The direct method was used to continuously monitor fan rotational speeds,and differential static pressures,coupled with periodic in-situ fan performance assessments,to calculate the VR.The indirect method consisted of estimating the VR using CO2 concentration measurements and the CO2 mass balance method.The average daily and hourly means(mean±SD)of directly measured barn ventilation rates for two years were(246±73)m3/s and(245±77)m3/s,respectively.The average daily and hourly means(mean±SD)of barn ventilation rates estimated by the CO2 mass balance method were(287±93.4)m3/s and(287±118)m3/s,respectively.Correlation analyses showed a strong correlation between the indirect CO2 mass balance method and direct measurement methods(r=0.93 for daily means and r=0.85 for hourly means).

Junction temperature measurement of alternating current light-emitting-diode by threshold voltage method

Junction temperature of alternating current light-emitting-diode （AC-LED） has a significant effect on its stable light output and lifetime. The threshold voltage measurement is employed to characterize the junction temperature of AC-LED, due to its excellent merits in high efficiency and accuracy. The threshold voltage is measured when the driving current of an AC-LED rises to a reference on-set value from the zero-crossing node. Based on multiple measurements of threshold voltage at different temperatures, a linear relationship was uncovered between the threshold voltage and the junction temperature of AC- LED with the correlating factor of temperature sensitive parameter （TSP）. Thereby, we can calculate the junction temperature with the TSP and threshold voltage once the AC-LED stays at thermal equilibrium state. The accuracy of the proposed junction temperature measurement technique was found to be ＋3.2℃ for the reference current of 1 mA. It is concluded that the method of threshold voltage is accurate and simple to implement, making it highly suitable for measuring the junction temperature of AC-LED in industry.

Dose escalation guided by^(18)F-FDG PET/CT for esophageal cancer

Objective:To assess the feasibility of dose escalation guided by ^(18)F-deoxyglucose positron emission tomography/computer tomography(^(18)F-FDG PET/CT)for esophageal cancer(EC).Methods and materials:Ten random patients treated with definitive chemoradiotherapy and pre-therapeutic ^(18)FFDG PET/CT were included in this study.Retrospectively,a threshold of 50%of SUVmax was used to define the high FDG uptake region of the GTV(GTVPET).Three intensity-modulated radiation therapy(IMRT)plans were generated,delivering three dose levels to three different planning target volumes(PTVs).50.4 Gy delivered to PTV50.4 was defined on computed tomography(CT)as Plan50.4,63 Gy was delivered to PTV63 was defined as GTV plus a uniform margin of 0.5 cm as Plan63,and 70 Gy delivered to PTV70 was defined as GTVPET plus a 0.5 cm margin as Plan70.A dosimetric comparison was performed based on normal tissue complication probability(NTCP)for the lung and heart.Results:Clinically acceptable dose escalation failed for 2 of 10 patients in Plan63 due to heart dose constraints.One patient failed heart dose constraint for Plan70.Two patients failed spinal cord constraint for Plan63.Three patients failed lung dose constraints for both Plan63 and Plan70,two of which were even not suitable for Plan50.4 for the same reason.NTCP modeling for lung showed increased risk for Plan63 and Plan70 compared to Plan50.4.The difference between Plan63 and Plan70 was insignificant.NTCP modeling for heart showed an increased risk from 6.38%of Plan50.4 to 8.88%of Plan70(P=0.009)or 9.79%of Plan63(P=0.007).The risk of heart mortality was significantly higher for Plan63 than Plan70(P=0.047).Conclusions:Selective boosting of sub-volumes based on ^(18)F-FDG PET/CT is feasible way with a modest increase in the risk of cardiac and lung toxicities.