腹部术后肺部并发症患者呼出气挥发性有机化合物分析

目的确定与腹部手术后患者发生术后肺部并发症（PPCs）相关的特征性呼出气挥发性有机化合物（VOCs）。方法本研究前瞻性、连续入组2022年12月10日至2023年6月30日在北京大学人民医院行腹部手术后转入重症监护病房（ICU）带气管插管的患者76例。采集患者围术期相关基本信息，并在患者入ICU后的24 h内经气管插管采集患者呼出气，进行气相色谱-质谱联用检测（GC-MS），分析患者呼出气VOCs成分。观察患者术后24 h采集呼出气后是否发生PPCs，将患者分为PPCs（n=44）组和无PPCs组（n=32），比较患病组和非患病组呼出气VOCs差异。应用Lasso回归分析筛选有价值VOCs变量，进而行Logistics回归分析，确定和PPCs相关的特征性VOCs。结果76例患者中发生PPCs者44例，无PPCs者32例，针对两组患者呼出气VOCs行Lasso回归分析，筛选出和PPCs可能相关的4种化合物，将4种化合物带入多因素Logistics回归分析，最终结果显示呼出气1-十六烷醇含量增高和PPCs的发生相关（OR： 1.000， P=0.002）。结论本研究显示腹部手术后患者呼出气中1-十六烷醇含量升高可能和PPCs的发生相关

Investigations on insecticidal efficacy of Bacillus thuringiensis preparations to the smaller tea tortrix, Adoxophyes sp. (Lepidoptera: Tortricidae).

本試驗中利用蘇力菌(Bacillus thuringiensis)之兩個商品化亞種B. thuringiensis subsp. aizawai及B. thuringiensis subsp. kustaki以國際單位(International unit; IU)為標準，對茶姬捲葉蛾(Adoxophyes sp.)幼蟲進行殺蟲效力測試。結果兩種蘇力菌均具有明顯的致病效果，且B. thuringiensis subsp. aizawai及 B. thuringiensis subsp. kustaki對四齡茶姬捲葉蛾LD50分別為8.6 IU/larva及4.4 IU/larva。不同齡期幼蟲接種B. thuringiensis subsp. aizawai後，其LT50 隨幼蟲齡期增加而增長。葉表施用後經陽光照射，蘇力菌的致病力隨日照時間增長而明顯的下降，顯示陽光照射會降低蘇力菌施用後的效果。在模擬田間降雨試驗中，以三種降雨強度對蘇力菌添加不同展著劑處理的茶樹葉片進行沖刷測試，較高強度的降雨確實對蘇力菌於葉片上的保留具有不良的影響。但是展著劑的添加在此三種降雨強度中，並不能有效的增加蘇力菌在葉片上殘留。由本研究測定蘇力菌製劑對茶姬捲葉蛾之殺蟲效力，並且模擬雨量沖刷與不同季節之環境條件對於蘇力菌殺蟲效力的影響。由所得到的結果，此微生物製劑似可供作實際防治之用。In this study, we used the preparations of two entomopathogenic bacteria, Bacillus thuringiensis subsp. aizawai (Bt-a) and B. thuringiensis subsp. kurstaki (Bt-k) based on international unit (IU) to examine the pathogenicity to the smaller tea tortrix, Adoxophyes sp. The LD50 values of B. thuringiensis subsp. aizawai and B. thuringiensis subsp. kurstaki to Adoxophyes sp. 4th instar larvae were 8.6 IU/ larva and 4.4 IU/ larva, respectively. The pathogenicity was not significantly different between two Bt preparations. When inoculated Adoxophyes sp. larvae with B. thuringiensis subsp. aizawai, the LT50 values increased with increasing larval instars. After exposing Bt-a sprays to different levels of solar radiation, the pathogenicity to Adoxophyes sp. larvae was decreased with increasing cumulative UV levels. Three simulated rainfall intensities were carried out for examining the wash-off of Bt sprays. The mortality of Adoxophyes sp. 4th instar larvae was decreased with increasing rainfall intensity. Addition of adjuvants to Bt preparations did not enhance adhesion on tea leaves at three rainfall intensities.. Based on pathogenic studies, it is suggested that B. thuringiensis preparations seem to be useful for biocontrol of the smaller tea tortrix.中文摘要 英文摘要 前言 文獻摘述 材料與方法 結果 討論 結論 參考文獻 圖表 附

簡析NFT之法律性質及監管

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土的基本特性及本构关系

面对土的外延持续拓展、内涵不断深化、本构模拟精度要求日趋提升的挑战,土的基本特性与本构关系研究要回归初心,面向工程需求,聚焦于达到工程分析精度而需要刻画的土的宏细观一体化特性,称作土的工程本征性。工程本征性主要有三相性、各向异性、摩擦性和剪胀性等几个方面,其内涵和发展趋势基于研究现状进行探讨。研究与刻画土的工程本征性时,应基于一体化的思路,注重细观特征和宏观特性刻画精度的均衡性,即:宏观层面的研究指导在细观层面有目标的观测,而不需要无止境的追求各类细观层面的细节;细观层面的研究为宏观层面的刻画提供充分依据,从而克服脱离细观机理的唯象假设。以土的工程本征性为核心探讨土的基本特性与本构关系研究的宏细观一体化建模方法,结合强度理论和多过程耦合模型等课题探讨研究现状与发展趋势。简要回顾本构理论研究的重要进展,指出土的本构理论研究已经具备深厚积累,以期为宏细观一体化的工程本征性研究奠定坚实的基础。With the development of geotechnical projects, the soil types continues to diversify, the soil behavior continues to complicate, and the soil constitutive model continues to be required for higher accuracy. Facing these challenges, the study on the fundamental behavior and constitutive relationship should focus on the integrated behaviors of the soil with macro-and micro-aspects that are essential for the required accuracy of engineering analysis. These behaviors are termed engineering characteristics of the soil, including three-phase feature, anisotropy, friction, and dilatancy. The contents and tendency are discussed based on the reviews of research literature. Integrated scheme, with a balance of analysis accuracy for the microstructure and macro-response, is required for the investigation and description of the engineering characteristics of the soil. In other words, the macro-investigation directs the micro-observations to avoid overemphasizing the pursuit of micro-details; while micro-investigation provide sufficient evidences to avoid assumptions without the micro-mechanism. The macro-and micro-integrated modeling schemes are proposed for the fundamental behavior and constitutive relationship of the soil on the basis of the engineering characteristics. The literature and development tendency are reviewed with the strength theory and multi-process coupling model of the soil. A brief review is conducted on the important development of the constitutive models of the soil. It is pointed out that the constitutive theories of the soil have established a firm foundation of the macro-and micro-integrated study on the engineering characteristics of the soil. © 2020, Editorial Office of China Civil Engineering Journal. All right reserved

Identification Shallow Foundation Bridge Scour Based on Routine Inspection Data

臺灣於2000年正式建置臺灣地區橋梁管理系統，以登錄每兩年一次之橋梁目視檢測資料，作為公路橋梁現況判釋的基礎。臺灣因山勢陡峭河川短促，過河橋梁毀損成因多與沖刷關係密切，然臺灣適用之沖刷評估表格目前尚未有一致性的共識，而地方政府在經費與人力均拮倨情況下，勢必極度仰賴橋梁目視檢測資料，作為判斷橋梁是否受沖刷威脅之依據。本文嘗試透過審視某一受沖刷損毀橋梁之目視檢測資料，發掘橋梁現況改變跡象與時間點，以瞭解定期目視檢測結果，可否足以提供判釋橋基受沖刷威脅之訊息。本文除提及美國一般橋梁目視檢測作業之外，並以美國橋梁檢測架構內之「關鍵發現」與「評分牽制」等兩類觀念切入，探討該案例橋檢測評分作業之缺失與誤判，須注意目視檢測評分沖刷相關項目之關聯性，補充註記檢測員意見哪些重要且必要事實，反映橋址沖刷潛藏徵兆，以期確切掌握與處置橋梁沖刷關鍵現況。The current web-based Taiwan Bridge Management System (TBMS), the most complete bridge database in Taiwan, was funded by the Ministry of Transportation and Communications (MOTC) in Taiwan in 2000. This bridge inventory archived biennial visual inspection data on more than 28,000 bridges in total and also provided as an official appraisal basis for highway bridge agencies. In Taiwan, bridges usually crossed rivers with severe channel variation. Most of the failure causes of cross-river bridges were associated with foundation scour and hydrological migration. Flood-induced scour could have continuously undermined the effective embedment depth of bridge foundation, degraded the structural stability of the abutment and piers, and severely threatened their safety. Several scour evaluation methods were developed for identifying scour-potential bridges in Taiwan in the past few years; unfortunately, a compromise agreement has not been reached by government and industrial circles yet. Meanwhile, in order to identify whether or not a bridge confronts scour threat and take a proper contingent action or plan, local governments limited in manpower and budget were bound to deeply reply the outcomes of the conventional visual inspection records. In this paper, the authors collected and reviewed the 10-year-long visual inspection records of one specific scour-damaged spread footing bridge located in central Taiwan. The qualitative changes of bridge site and its surrounding environmental condition were updated and re-constructed on the whole bridge history based each routine inspection. A conventional field investigation was also executed to assemble relevant disaster information immediately after its single span falling accident. A comprehensive overview into the progressive scour was conducted to determine whether visual inspection database could play a useful source on a bridge scour event or not. For integrity and consistency concerns on data were found in the bridge inspection recording and rating, visual inspection information could partially reflect the severity of scour threat on the bridge piers. This paper also reviewed the information of the National Bridge Inspection Standards (NBIS) implemented by the Federal Highway Administration (FHWA) in the U.S. The NBIS firmly required bridge agencies and contractors to record and code all aberration or deficiency findings in visual inspection. Relevant images, sketches, written description should be attached as part of bridge inspection documentation in detail. In order to overcome blind spots in the common bridge visual inspection process, the NBIS provides two another key concepts, Critical Finding and Coding Collocation, which guide crucial conditions for structural or safety issues and re-code tight relation inspection items, respectively. Using these two filter mechanisms could effectively identify the turning point of scour aggravation and inform the bridge agencies to take an efficient action or countermeasure in time before tragedy occurrence. Based on the above steps, the deficiency and miscoding could be interpreted and recognized on this proposed bridge in routine inspection operation used in Taiwan. The bridge inspectors should cautiously notice scour-related inspection items, such as waterway, pier foundation, protection works, abutment, and abutment foundation, record important and necessary deficiencies in detail, and give integrated judgment on scour symptoms and engineering suggestions in the future

超声速燃烧室对流传热特性数值研究

超燃冲压发动机的热防护始终是高超声速飞行器的关键技术之一。作为发动机核心部件的燃烧室,其热环境最为恶劣。对于马赫6的飞行条件,燃烧室内燃气的总温接近3 000K,壁面热流局部高达2～5 MW/m~2。采用机载燃料作为冷却剂,导入燃烧室固壁内的冷却通道,利用对流换热和裂解化学吸热机制吸收热量、降低壁温,是一种公认的有效热防护方法。在冷却结构的设计中,能否获得详细的热载荷分布显得至关重要。由于超声速燃烧室内气流温度、速度高以及流动与结构的多尺度,采用常规的测温、测热流技术较难获得高分辨率数据,同时光学诊断方法难以获得壁面参数信息。因此,高精度的数值模拟和理论分析方法将提供详细的空间分布数据。这里需..

A Coupled Heat Transfer Analysis with Effects of Catalytic Cracking of Kerosene for Actively Cooled Supersonic Combustor

为了分析宽马赫数飞行条件下超声速燃烧室再生冷却性能以及考虑燃料高温裂解效应对冷却的影响,发展了具有一定通用性的超声速燃烧室再生冷却系统气-固-液传热分析模型,对燃烧室内流、冷却剂流动以及冷却结构进行了气-固-液传热耦合计算。燃烧室内流计算模型无需实验测量的静压数据以及总温/释热分布假设,通过直接求解质量、动量、能量守恒微分方程并结合燃料混合及燃烧模型来获得内流参数分布。同时对燃烧室壁面传热进行了计算,将冷却结构内冷却剂的流动、换热与燃烧室内流耦合,并且着重考虑了煤油作为冷却剂,其物态随温度、压力变化以及高温时出现的热/催化裂解吸热化学反应。基于实验数据发展了煤油热/催化裂解总包反应模型,对煤油热裂解和催化裂解两种过程的化学吸热性能进行了对比,研究了热/催化裂解效应对再生冷却的影响

考虑煤油热/催化裂解效应的超声速燃烧室冷却系统气-固-液耦合传热分析

本文发展了具有一定通用性的超燃冲压发动机燃烧室流动与传热一维分析模型,对燃烧室内流、冷却剂流动以及冷却结构进行了气一固一液传热耦合计算。所采用的内流计算模型无需实验测量的静压数据以及总温/释热分布假设,直接求解质量、动量、能量守恒微分方程并结合燃料混合及燃烧模型来获得内流参数分布。同时对燃烧室壁面传热进行了计算,将冷却结构内冷却剂流动

A coupled heat transfer analysis with effects of thermal/catalytic cracking of kerosene for regenerative cooled supersonic combustor

In this paper,a heat transfer analysis coupling the combustor flow, the coolant flow(on-board hydrocarbon fuel) and the cooling wall was introduced for the study of regenerative cooling of supersonic combustor.The combustor flow was determined by solving differential equations of mass,momentum an..