大体积混凝土裂缝成因分析

随着社会经济的发展,各种大型、特大型的混凝土结构物即大体积混凝土与日俱增。我国在《普通混凝土配合比设计规程》一书中,对大体积混凝土解释为"混凝土结构物中实体最小尺寸大于或等于1 m或易引起裂缝的混凝土"。文章针对大体积混凝土施工中容易出现的裂缝问题,进行了一系列的原因分析,并提出防治措施,以避免裂缝的产生。     

聚氯乙烯热稳定剂种类的研究现状

概述了聚氯乙烯(PVC)的热降解机理及热稳定剂的作用机理,重点介绍了铅盐类稳定剂、金属皂类稳定剂、有机锡类稳定剂、稀土类稳定剂等的研究发展情况,对热稳定剂的发展趋势进行了展望。     

论教学督导模式对提高高职院校教学质量的保障作用

教学督导对高校教学质量的提高起着保驾护航的作用,为了有效地发挥督导体系对高职院校教学质量的保障作用,应当健全教学督导工作制度,形成特色的高职高专督导运行模式,丰富并拓展教学督导工作的方法和内涵,构建科学合理的督导运行机制。     

通信用热交换型户外机柜节能降噪设计

通信用热交换型户外机柜节能降噪设计突破常规使用的集成式热交换器的设计,以一个全新设计的机柜结构,以最简单的风机加散热风道的设计革新了热交换户外机柜的设计,在直接成本、噪音、能耗上均比集成式热交换户外机柜要好,甚至在噪音和能耗上高于风扇型户外机柜,各项性能指标均高于行标。真正达到功耗小、无污染、防护等级高。     

节能减排下热电联产燃机项目电价政策的思考

随着天然气价格上涨,燃机发电上网电价政策成为热电联产燃机项目生存的重要条件之一.通过理论分析和实证检验,就当前热电联产燃机发电上网的＂高电价＂对燃机项目运营的影响进行了探讨,结果表明：相对于热价,偏高的上网电价易导致电厂愿意多发电,少供热,结果降低了全厂的热效率,不利于全社会的节能降耗.     

Disease-specific cost savings of treating nighttime versus daytime gastroesophageal reflux disease in an employed population

Summary

Objective: The extent to which proton pump inhibitors (PPIs) can offset direct medical costs by reducing symptoms related to gastroesophageal reflux disease (GERD) in order to improve work productivity is not well understood. This study aimed to evaluate the economic impact of treating GERD with PPIs versus no treatment, from an employer's perspective.

Study design: An economic model was developed to simulate symptom reduction and breakthrough symptoms as well as associated costs over 1 year among a population of 100,000 with a 20% GERD prevalence rate. Medical costs, including GERD-related office visits, hospitalisations and procedures, were delineated by symptom severity. Indirect costs represented the monetised work productivity loss. PPI treatment costs $2/day (standard dose).

Results: The GERD burden was substantial ($62,500,000). Treatment yielded $32,600,000 in savings ($1,630 saved/patient/year), mostly from reducing indirect costs. Treatment produced greater savings among nighttime GERD patients throughout the PPI cost range ($1–$5/day). Savings dropped if the price of standard doses of PPI exceeded $3.92/day for the treatment of daytime GERD patients.     

试析人类耗用能源对气候变暖的贡献

在对地球气候变暖原因的探讨中，人们较注意“温室气体”的贡献，但与“温室气体”排放几乎同时进行的巨额热量的释放也是不应 忽视的；由205个国家和地区在1年内消耗的商品能源量数据。计算出每年释放的热量相当于地球接受30分钟的太阳辐射量，在绝热情况下可使全球陆地2m厚的表层、全球海洋2m深的水体和全球大气温度提高0.06℃；对上述结果进行了讨论。     

Pediatric gastroesophageal reflux disease and acid-related conditions: trends in incidence of diagnosis and acid suppression therapy

Abstract

Objective: To describe the incidence of diagnosis of gastroesophageal reflux disease and acid-related conditions (GERD/ARC) throughout childhood and characterize patterns of diagnosis and treatment with proton pump inhibitors (PPIs) and histamine-2 receptor antagonists (H₂RAs).

Methods: Cohorts of GERD/ARC children (age 0–18 years) were identified from a large US administrative claims database covering 1999–2005 using ICD-9 codes. Incidence, healthcare utilization (HCU), costs, therapy discontinuation and switching rates were compared between various age and patient groups.

Results: Between 2000 and 2005 annual incidence of GERD/ARC diagnosis among infants (age ≤1 year) more than tripled (from 3.4 to 12.3%) and increased by 30% to 50% in other age groups. Patients diagnosed by GI specialists (9.2%) were more likely to be treated with PPIs compared to patients diagnosed by primary care physician (PCP). PPI-initiated patients doubled (from 31.5% in 1999 to 62.6% in 2005) and, when compared with H₂RA-initiated patients, were associated with 30% less discontinuation and 90% less therapy switching in the first month, and with higher comorbidity burden and pre-treatment total HCU and costs when diagnosed by GI specialists.

Limitations: The use of an exploratory definition for GERD/ARC, administrative claims data and potential coding errors in diagnosis codes used in selection process may limit the generalizability of the results.

Conclusions: GERD/ARC incidence increased for children of all ages between 2000 and 2005. PCPs made the majority of diagnoses. PPI initiations have now surpassed H₂RA initiations.     

广义基本解方法求解具有一类特殊热源的热传导方程反边界值问题

给出一种求解具有一类特殊热源的非齐次热传导方程反边界值问题的无网格方法，即广义基本解方法．该方法将问题的解分成特解和相应齐次问题的解两个部分：齐次解用基本解方法求解，而特解则是利用源项的特殊性由相应的特征方程的基本解近似得到．最后给出数值例子说明该方法的稳定性和有效性．