Cell-free massive multiple-input multipleoutput(MIMO)is a promising technology for future wireless communications,where a large number of distributed access points(APs)simultaneously serve all users over the same time...Cell-free massive multiple-input multipleoutput(MIMO)is a promising technology for future wireless communications,where a large number of distributed access points(APs)simultaneously serve all users over the same time-frequency resources.Since users and APs may locate close to each other,the line-of-sight(Lo S)transmission occurs more frequently in cell-free massive MIMO systems.Hence,in this paper,we investigate the cell-free massive MIMO system with Lo S and non-line-of-sight(NLo S)transmissions,where APs and users are both distributed according to Poisson point process.Using tools from stochastic geometry,we derive a tight lower bound for the user downlink achievable rate and we further obtain the energy efficiency(EE)by considering the power consumption on downlink payload transmissions and circuitry dissipation.Based on the analysis,the optimal AP density and AP antenna number that maximize the EE are obtained.It is found that compared with the previous work that only considers NLo S transmissions,the actual optimal AP density should be much smaller,and the maximized EE is actually much higher.展开更多
A metropolitan city such as Los Angeles (LA) is an ideal study site with a very high population density, and it houses at least 3 treatment plants where sewage is treated preliminarily and then progressing to tertiary...A metropolitan city such as Los Angeles (LA) is an ideal study site with a very high population density, and it houses at least 3 treatment plants where sewage is treated preliminarily and then progressing to tertiary treatment before discharging into the LA River. We will gain a better understanding of the water quality in the LA River and the nitrate load in the watershed system by examining the influence of waste water treatment plants (WWTPs). The goal of this study is to pinpoint the exact source of nitrate in the LA River using the isotope signatures. We have selected sampling locations both upstream and downstream of the WWTP. This serves to monitor nitrate levels, aiding in the assessment of treatment plant effectiveness, pinpointing nitrate pollution sources, and ensuring compliance with environmental regulations. The research explores the isotopic composition of NO3 in relation to atmospheric nitrogen and Vienna Standard Mean Ocean Water, shedding light on the contributions from various sources such as manure, sewage, soil organic nitrogen, and nitrogen fertilizers. Specifically, there is a change in the δ15NAir value between the dry and wet seasons. The isotope values in the Tillman WWTP sample changed between dry and wet seasons. Notably, the presence of nitrate originating from manure and sewage is consistent across seasons, emphasizing the significant impact of anthropogenic and agricultural activities on water quality. This investigation contributes to the broader understanding of nitrogen cycling in urban water bodies, particularly in the context of wastewater effluent discharge. The findings hold implications for water quality management and highlight the need for targeted interventions to mitigate the impact of nitrogen-containing compounds on aquatic ecosystems. Overall, the study provides a valuable framework for future research and environmental stewardship efforts aimed at preserving the health and sustainability of urban water resources. This data informs decisions regarding additional treatment or mitigation actions to safeguard downstream water quality and ecosystem health.展开更多
目的比较非肽类血管紧张素Ⅱ受体Ⅰ型阻断剂氯沙坦(Losartan)和血管活性肽降钙素基因相关肽(CGRP)对血管紧张素Ⅱ诱导的血管平滑肌细胞增殖作用的影响,为探讨此两类物质的降压机制提供实验依据。方法采用MTT,3H-参入法和流式细胞仪分别...目的比较非肽类血管紧张素Ⅱ受体Ⅰ型阻断剂氯沙坦(Losartan)和血管活性肽降钙素基因相关肽(CGRP)对血管紧张素Ⅱ诱导的血管平滑肌细胞增殖作用的影响,为探讨此两类物质的降压机制提供实验依据。方法采用MTT,3H-参入法和流式细胞仪分别测定血管紧张素Ⅱ刺激下,Losartan或CGRP干预下血管平滑肌细胞的增殖变化,W est-ern b loting法测定不同状态下血管平滑肌细胞内ERK1/2的活性变化。结果Losartan或CGRP能抑制血管紧张素Ⅱ刺激下血管平滑肌细胞的生存率、DNA合成、细胞周期增殖指数,以及细胞内ERK1/2的活性,并呈剂量依赖性。而且,CGRP抑制作用强于Losartan。结论Losartan或CGRP能抑制血管紧张素Ⅱ刺激下血管平滑肌细胞增殖,其细胞内的信号传导途径与ERK1/2有关。展开更多
Aim To evaluate the bioequivalence of two brands of losartan/hydrochlorothiazide （50 mg/12.5 mg） compound tablets in healthy Chinese male volunteers. Methods An open, randomized, single-dose, two-period cross-over s...Aim To evaluate the bioequivalence of two brands of losartan/hydrochlorothiazide （50 mg/12.5 mg） compound tablets in healthy Chinese male volunteers. Methods An open, randomized, single-dose, two-period cross-over study with a wash-out period of 7 d was conducted. Twenty healthy male volunteers were given a single dose 50 mg losartan/12.5 mg hydrochlorothiazide of either test （T） or reference （R） compound tablets, respectively. Blood samples were collected up to 48 h after oral administration. The concentrations of losartan and hydrochlorothiazide in plasma were determined by a validated HPLC-ESI-MS method. Results In the case of losartan, the 90% confidence intervals of two one-side test for percent ratios with a significant level （α） of 0. 05 were 86% - 112% for AUC0-12 and 89% - 134% for Cmax, respectively, which were within the interval proposed in the Chinese Pharmacopoeia, 80% - 125% of AUC and 70% - 143% of Cmax, respectively. Similarly, the 90% confidence intervals for percent ratios were 85% - 100% and 75% - 102% for hydrochlorothiazide, both of which fell into the accepted interval. Conclusion Two immediate-release compound tablets of losartan/hydrochlorothiazide are bioequivalent from a statistical standpoint in the extent and rate of absorption from the single-dose study in healthy Chinese male volunteers.展开更多
基金supported in part by the National Natural Science Foundation of China under Grant 62171231in part by the Jiangsu Provincial Key Research and Development Program(No.BE2020084-1)。
文摘Cell-free massive multiple-input multipleoutput(MIMO)is a promising technology for future wireless communications,where a large number of distributed access points(APs)simultaneously serve all users over the same time-frequency resources.Since users and APs may locate close to each other,the line-of-sight(Lo S)transmission occurs more frequently in cell-free massive MIMO systems.Hence,in this paper,we investigate the cell-free massive MIMO system with Lo S and non-line-of-sight(NLo S)transmissions,where APs and users are both distributed according to Poisson point process.Using tools from stochastic geometry,we derive a tight lower bound for the user downlink achievable rate and we further obtain the energy efficiency(EE)by considering the power consumption on downlink payload transmissions and circuitry dissipation.Based on the analysis,the optimal AP density and AP antenna number that maximize the EE are obtained.It is found that compared with the previous work that only considers NLo S transmissions,the actual optimal AP density should be much smaller,and the maximized EE is actually much higher.
文摘A metropolitan city such as Los Angeles (LA) is an ideal study site with a very high population density, and it houses at least 3 treatment plants where sewage is treated preliminarily and then progressing to tertiary treatment before discharging into the LA River. We will gain a better understanding of the water quality in the LA River and the nitrate load in the watershed system by examining the influence of waste water treatment plants (WWTPs). The goal of this study is to pinpoint the exact source of nitrate in the LA River using the isotope signatures. We have selected sampling locations both upstream and downstream of the WWTP. This serves to monitor nitrate levels, aiding in the assessment of treatment plant effectiveness, pinpointing nitrate pollution sources, and ensuring compliance with environmental regulations. The research explores the isotopic composition of NO3 in relation to atmospheric nitrogen and Vienna Standard Mean Ocean Water, shedding light on the contributions from various sources such as manure, sewage, soil organic nitrogen, and nitrogen fertilizers. Specifically, there is a change in the δ15NAir value between the dry and wet seasons. The isotope values in the Tillman WWTP sample changed between dry and wet seasons. Notably, the presence of nitrate originating from manure and sewage is consistent across seasons, emphasizing the significant impact of anthropogenic and agricultural activities on water quality. This investigation contributes to the broader understanding of nitrogen cycling in urban water bodies, particularly in the context of wastewater effluent discharge. The findings hold implications for water quality management and highlight the need for targeted interventions to mitigate the impact of nitrogen-containing compounds on aquatic ecosystems. Overall, the study provides a valuable framework for future research and environmental stewardship efforts aimed at preserving the health and sustainability of urban water resources. This data informs decisions regarding additional treatment or mitigation actions to safeguard downstream water quality and ecosystem health.
文摘目的比较非肽类血管紧张素Ⅱ受体Ⅰ型阻断剂氯沙坦(Losartan)和血管活性肽降钙素基因相关肽(CGRP)对血管紧张素Ⅱ诱导的血管平滑肌细胞增殖作用的影响,为探讨此两类物质的降压机制提供实验依据。方法采用MTT,3H-参入法和流式细胞仪分别测定血管紧张素Ⅱ刺激下,Losartan或CGRP干预下血管平滑肌细胞的增殖变化,W est-ern b loting法测定不同状态下血管平滑肌细胞内ERK1/2的活性变化。结果Losartan或CGRP能抑制血管紧张素Ⅱ刺激下血管平滑肌细胞的生存率、DNA合成、细胞周期增殖指数,以及细胞内ERK1/2的活性,并呈剂量依赖性。而且,CGRP抑制作用强于Losartan。结论Losartan或CGRP能抑制血管紧张素Ⅱ刺激下血管平滑肌细胞增殖,其细胞内的信号传导途径与ERK1/2有关。
文摘Aim To evaluate the bioequivalence of two brands of losartan/hydrochlorothiazide （50 mg/12.5 mg） compound tablets in healthy Chinese male volunteers. Methods An open, randomized, single-dose, two-period cross-over study with a wash-out period of 7 d was conducted. Twenty healthy male volunteers were given a single dose 50 mg losartan/12.5 mg hydrochlorothiazide of either test （T） or reference （R） compound tablets, respectively. Blood samples were collected up to 48 h after oral administration. The concentrations of losartan and hydrochlorothiazide in plasma were determined by a validated HPLC-ESI-MS method. Results In the case of losartan, the 90% confidence intervals of two one-side test for percent ratios with a significant level （α） of 0. 05 were 86% - 112% for AUC0-12 and 89% - 134% for Cmax, respectively, which were within the interval proposed in the Chinese Pharmacopoeia, 80% - 125% of AUC and 70% - 143% of Cmax, respectively. Similarly, the 90% confidence intervals for percent ratios were 85% - 100% and 75% - 102% for hydrochlorothiazide, both of which fell into the accepted interval. Conclusion Two immediate-release compound tablets of losartan/hydrochlorothiazide are bioequivalent from a statistical standpoint in the extent and rate of absorption from the single-dose study in healthy Chinese male volunteers.
文摘目的 研究 L osartan对肾小球系膜细胞 (MCs)结缔组织生长因子 (CTGF)表达的影响。进一步探讨 L osartan延缓肾纤维化的机制。方法 将体外培养的 MCs分为 3组 :1正常对照组 ,未加任何刺激因素 ;2浓度为 10 - 5mol/L 的 Ang 组 ;3Ang 中加入 10 - 5m ol/L 的 L osartan组。分别刺激 MCs72小时后 ,提取细胞RNA,采用逆转录 -聚合酶链反应技术测定 MCs CTGF m RNA水平变化。结果 L osartan干预 72小时后 ,MCsCTGF m RNA表达水平较 Ang 组下降 2 5 .1%,但仍高于对照 ,为对照组的 1.95倍。结论 L osartan通过部分抑制 Ang 对 CTGF m RNA表达的诱导而有益于延缓肾纤维化的进展 ,这可能是 L osartan延缓肾纤维化的机制。
