The Dangerous Middle: Situational Awareness and Worker Perception of Beetle Kill

ABSTRACT

Forest workers, including loggers, foresters, and wildland firefighters, are regularly exposed to some of the most fatal occupational environments in the United States. These hazardous work environments may become even more complex and dynamic when subject to bark beetle outbreaks that have resulted in significant tree mortality. The impacts of tree death from bark beetles are significant, with the cumulative 17-year (2000–2016) footprint for bark beetle caused tree mortality estimated at 54 million acres. However, how workers think about and act in these environments is understudied. This study, therefore, approaches the issue of beetle kill and forest worker safety by examining the perspectives or workers themselves. Its contribution is to leverage ethnographic research to provide insights that can generate new research questions, better inform outreach, and ultimately improve worker safety outcomes. The resulting insights show that beetle kill was understood by workers as a hazard that increased the complexity and dynamism of the work environment, making situational awareness both more necessary and more difficult to maintain. While much research about situational awareness focuses on hazardous situations, it is suggested that building adequate situational awareness should also include broader considerations of organizational communication, as well as training and experience considered over the course of entire careers.     

rIL－2/LAK细胞治疗晚期恶性肿瘤

 胎儿来源的LAK细胞/rIL-2对5例失去手术、化疗、放疗机会的晚期恶性肿瘤病人进行了过继免疫治疗。结果都取得了-定的疗效,黑色素瘤病人肺转移结节基本消失,局部瘤细胞全部坏死,组织细胞正常;淋巴瘤病人转移灶消退59%;小肠平滑肌肉瘤病人在没进行此疗法之前2年半复发、手术三次。第三次手术后用此疗法治疗-个疗程,三年后第-次复发。为晚期恶性肿瘤病人延长了生命,提高了生存质量争得了再次治疗的机会。     

Pharmacokinetic/ pharmacodynamic evaluation of anti-infective agents

Pharmacokinetic/pharmacodynamic modeling has become an extremely important tool in evaluating and optimizing anti-infective therapy. By systematically linking the pharmacokinetic and pharmacodynamic properties of the anti-infective agent, it is possible to make educated decisions about the correct drug to be used, correct dosing regimen and to estimate the probability of success with the selected dose regimen. This article gives an overview of the current pharmacokinetic/pharmacodynamic approaches for anti-infective agents and discusses their use in optimizing drug therapy.     

Cell-wall-inhibiting antibiotic combinations with activity against multidrug-resistant Klebsiella pneumoniae and Escherichia coli

The increasing prevalence of hospital and community-acquired infections caused by multidrug-resistant (MDR) bacterial pathogens is rapidly limiting the options for effective antibiotic therapy. Systematic studies on combinations of already available antibiotics that could provide an effective treatment against MDR bacteria are needed. We tested combinations of antibiotics that target one important physiological function (peptidoglycan synthesis) at several steps, and studied Enterobacteriaceae (Klebsiella pneumoniae and Escherichia coli) for which multidrug resistance associated with ESBL-producing plasmids has become a major problem. To measure the effectiveness of antibiotics alone and in combination, we used checkerboard assays, static antibiotic concentration time-kill assays, and an improved in-vitro kinetic model that simulates human pharmacokinetics of multiple simultaneously administered antibiotics. The target strains included an MDR K. pneumoniae isolate responsible for a recent major hospital outbreak. A double combination (fosfomycin and aztreonam) and a triple combination (fosfomycin, aztreonam and mecillinam) were both highly effective in reducing bacterial populations in all assays, including the in vitro kinetic model. These combinations were effective even though each of the MDR strains was resistant to aztreonam alone. Our results provide an initial validation of the potential usefulness of a combination of antibiotics targeting peptidoglycan synthesis in the treatment of MDR Gram-negative bacteria. We suggest that a combination of fosfomycin with aztreonam could become a useful treatment option for such infections and should be further studied.     

Three endpoints of in vivo tumour radiobiology and their statistical estimation

Purpose:?To review the existing endpoints of tumour growth delay assays in experimental radiobiology with an emphasis on their efficient estimation for statistically significant identification of the treatment effect. To mathematically define doubling time (DT), tumour-growth delay (TGD) and cancer-cell surviving fraction (SF) in?vivo using exponential growth and regrowth models with tumour volume measurements obtained from animal experiments.

Materials and methods:?A statistical model-based approach is used to define and efficiently estimate the three endpoints of tumour therapy in experimental cancer research.

Results:?The log scale is advocated for plotting the tumour volume data and the respective analysis. Therefore, the geometric mean should be used to display the mean tumour volume data, and the group comparison should be a t-test for the log volume to comply with the Gaussian-distribution assumption. The relationship between cancer-cell SF, TGD and rate of growth is rigorously established. The widespread formula for cell kill is corrected; it has been rigorously shown that TGD is the difference between DTs. The software for the tumour growth delay analysis based on the mixed modeling approach with a complete set of instructions and example can be found on the author's webpage.

Conclusions:?The existing practice for TGD data analysis from animal experiments suffers from imprecision and large standard errors that yield low power and statistically insignificant treatment effect. This practice should be replaced with a model-based statistical analysis on the log scale.     

杀伤细胞免疫球蛋白样受体基因及其配体相合或错配对单倍相合骨髓移植效果的影响

本研究分析杀伤细胞免疫球蛋白样受体（killer cell Ig-like receptor,KIR）及其配体分子相合与否对单倍体相合骨髓移植效果的影响。分析了74例KIR基因及其配体分子HLA-Cw的分布频率和特点,同时比较KIR分子配体缺失与否对单倍相合骨髓移植患者总体生存、无病生存、GVHD发生以及复发等的影响。结果表明：19个KIR基因表型中2DL1、2DL4和3DL2-3在所有个体100%分布,其他高频率分布的还有3DP1（98.6%）、2DP1（98.6%）、3DL1（97.3%）、2DL3（97.3%）;抑制型基因分布频次是活化型的1.37倍;所有单倍体都含有2DL1、KIR3DL2、3DL3和2DL4,其中每个单倍体中均含有2DL2和/或2DL3。HLA-C14个等位基因中Cw7分布频率最高为37.8%;KIR2DL2/2DL3识别配体Group2（HLA-Cw1,3,7,8,13,14）组占43.2%。32例单倍相合骨髓移植中KIR基因错配发生比例为43.8%,其中9/14例为2DL不相合、5/14为2DL2或3DL1不相合;46对单倍相合骨髓移植中HLA-Cw全相合者29例,不相合者14例,HLA-Cw发生完全错配比例为30.4%,全相合比例为63.4%。14例KIR基因不相合和13例KIR基因相合移植病例中,KIR基因相合组生存率高于KIR基因不相合者（p=0.032）;17例KIR分子配体HLA-Cw不相合移植患者的DFS明显高于24例相合者（p=0.024）。按供受者KIR配体是缺失的GVHD矢量组生存率高于非GVHD矢量组（p=0.015）。急性重症GVHD发生与活化型KIR2DS1/2DS2有关,2DS1/2DS2不相合组高发急性重症GVHD同时复发减低,而2DS1/2DS2相合组低GVHD但是复发增多。14例KIR配体不相合髓系白血病患者骨髓移植后1例复发死亡,而12例KIR配体相合组患者有4例复发死亡。结论：单倍体相合骨髓移植的主要特点就是HLA不全相合,KIR基因表型不一致性及其配体缺失也是其主要免疫学特征,供者型KIR配体的缺失与移植效果有密切关系,在单倍相合移植中分析KIR基因及其配体对于供者选择和判断预后有重要意义。     

蜣螂中氨基酸的测定

目的测定蜣螂中总氨基酸和游离氨基酸的含量。方法采用氨基酸分析仪测定。结果蜣螂中游离氨基酸的含量为2.07%,总氨基酸为40.58%,其中8种必需氨基酸的含量占总氨基酸含量的35.87%,谷氨酸、甘氨酸、丙氨酸的含量较高,共占总氨基酸含量的29.55%。结论蜣螂的游离氨基酸含量远低于总氨基酸。