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1.
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.  相似文献   
2.
用混合粘合剂碳糊电极测定丁螺环酮   总被引:6,自引:1,他引:5  
用混合粘合剂碳糊电极测定丁螺环酮张正奇,曾鸽鸣,刘传桂,黎艳飞(湖南大学化学化工系,长沙410082)碳糊电极无毒,制作方便,表面更新容易,应用电位范围广,在药物分析中已有应用[1~5]。我们在液体石腊中加入添加剂,组成混合粘合剂,可显著改善电极的检...  相似文献   
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OBJECTIVE: To determine factors influencing rationing decisions in a surgical ICU during a temporary nursing shortage when two to six of the unit's 16 beds were closed. DESIGN: Blinded, concurrent data collection, retrospective chart review. SETTING: Surgical ICU. PATIENTS: All patients (n = 308) for whom a surgical ICU bed was requested were studied during a 3-month period. MEASUREMENTS AND MAIN RESULTS: Admitting patterns did not change and no attempts were made to limit admissions to more severely ill patients during times of the greatest shortage of surgical ICU beds. Contrary to findings in previous reports, the severity of illness of patients admitted to the surgical ICU decreased as bed availability and bed census decreased. Bed allocation across surgical services was influenced by factors other than medical suitability. Of major users, cardiothoracic surgery experienced the highest percentage (59%) of all patient admissions and lowest percentage (1.6%) of all denied admissions. General surgery experienced the lowest percentage (15%) of all admissions and highest percentage (10.4%) of all denied admissions, although these patients had the highest average Acute Physiology and Chronic Health Evaluation (APACHE II) scores for all patients admitted (17.7) and for patients denied admission (15.8). CONCLUSIONS: Surgical attending physicians rarely used other open inhouse ICU beds when surgical ICU beds were unavailable. Political power, medical provincialism, and income maximization overrode medical suitability in the provision of critical care services.  相似文献   
5.
Two types of fluid regimen were provided for patients having labour induced under epidural analgesia. Reasons for the infusion were to pre-load the circulation before the epidural, and subsequently to sustain maternal hydration. Both fluids were isotonic, one was predominantly saline based (Hartmann's solution) and the other contained both saline and dextrose. Blood glucose and serum sodium, lactate and beta-hydroxybutyrate were measured before the start of induction, at delivery and in the cord sample. Blood glucose and serum sodium were measured in the babies at 12 and 24 h of age. The dextrose-saline fluid caused small but significant changes in blood glucose and serum sodium which did not exceed the normal reference limits for either. The use of Hartmann's solution was associated with considerable rises in maternal serum beta-hydroxybutyrate at delivery. Neither fluid had any significant effect on the blood glucose or serum sodium in infants at 12 and 24 h of age.  相似文献   
6.
CG Teo 《Oral diseases》2002,8(S2):88-90
Oral hairy leukoplakia (OHL) and Kaposi's sarcoma (KS) are commonly encountered in the HIV-infected patient. A unique feature of OHL is non-cytolytic high level of replication of Epstein–Barr virus (EBV) in the glossal epithelium. The expression of viral-encoded anti-apoptotic proteins concomitant to replicative proteins probably underlies this phenomenon. The question of whether OHL arises from activation of EBV latent in the tongue, or from superinfection by endogenous EBV shed via non-glossal sites or by exogenous EBV remains unresolved. Human herpesvirus 8 (HHV8) is now seen as necessary but not sufficient cause of KS. Expression of HHV8-encoded oncogenic proteins in endothelial cells probably explains the aberrant proliferation of these cells in KS lesions. Studies into why KS is so commonly observed at the palate in HIV-infected patients may provide important clues to its pathogenesis.  相似文献   
7.
Background: The ideal intrathecal isobaric bupivacaine dose for cesarean delivery anesthesia is uncertain. While small doses (5-9 mg) of bupivacaine may reduce side effects such as hypotension, they potentially increase spinal anesthetic failures. This study determined the ED50 and ED95 of intrathecal isobaric bupivacaine (with adjuvant opioids) for cesarean delivery.

Methods: After institutional review board approval and written informed consent were obtained, 48 parturients undergoing elective cesarean delivery under combined spinal-epidural anesthesia were enrolled in this double-blind, randomized, dose-ranging study. Patients received a 5-, 6-, 7-, 8-, 9-, 10-, 11-, or 12-mg intrathecal isobaric bupivacaine dose with 10 [mu]g fentanyl and 200 [mu]g morphine. Overall anesthetic success was recorded when no intraoperative epidural supplement was required during the cesarean delivery. ED50 and ED95 values for overall anesthetic success were determined using a logistic regression model.

Results: ED50 and ED95 values for overall anesthetic success were 7.25 and 13.0 mg, respectively. No advantages for low doses could be demonstrated with regard to hypotension, nausea, vomiting, pruritus, or maternal satisfaction, although this study was underpowered to detect significant differences in secondary outcome variables.  相似文献   

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One goal of supportive housing is to enlarge and improve the functioning of the social support networks of residents. The networks of a convenience sample of 42 residents were assessed using scales developed by Barrera. The size of the networks (11.5) was no larger than that reported for similar clients living in other types of community settings but the composition differed. Staff and co-residents appear to partially replace rather than add to family and friends. This is of concern because friends are uniquely important determinants of satisfaction. An association between perceived need for support and network size was also found. These findings suggest some positive influences but also raise questions about unintended negative consequences of living in artificially constructed social environments.When this project was undertaken, Dr. Goering, Janet Durbin, Bill Lancee and Taras Babiak were all members of the Social and Community Psychiatry Section, Clarke Institute. Robert Foster was Executive Director of Regeneration House, Inc., where Susan Boyles is Assistant Executive Director.  相似文献   
10.
This paper describes a new sensitive microELISA based on enzyme/anti-enzyme complexes following an unlabelled antibody bridging step. beta-Galactosidase/anti-beta-galactosidase complexes were made using a monoclonal antibody raised against bacterial (E. coli) beta-galactosidase and enzyme activity was quantified with a fluorogenic substrate. Because of its high sensitivity the assay is particularly suitable for the detection of limited amounts of antigen. One application illustrated is the analysis of Class I and Class II histocompatibility antigens on peripheral blood lymphocytes using 5000 cells/well in 60-well Terasaki or 96-well microtitre plates.  相似文献   
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