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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   
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FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease.  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   
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Development of a new wound dressing with antimicrobial delivery capability   总被引:1,自引:0,他引:1  
A bilaminar wound dressing composed of an outer membrane and an inner three-dimensional matrix of a fabric or a sponge may be considered to constitute an ideal structure that promotes wound healing: the outer membrane prevents body fluid loss, controls water evaporation, and protects the wound surface from bacterial invasion, and the inner matrix encourages adherence by tissue growth into the matrix. Using this concept, we developed a biosynthetic wound dressing with a drug delivery capability. This medicated wound dressing is composed of a spongy sheet of a chitosane derivative and collagen mixture that is laminated to an antimicrobial-impregnated polyurethane membrane. In this study, a gentamycin sulfate-impregnated wound dressing was prepared and evaluated. The antimicrobial efficacy of this wound dressing was examined on an agar plate seeded with Pseudomonas aeruginosa. Also, the cytotoxicity of an antimicrobial released from this wound dressing was examined in an in vitro system with cultured skin substitutes. Both in vitro tests have shown that this wound dressing is capable of suppressing bacterial growth and minimizing cellular damage. In addition, in the treatment of wounds inflicted on rats and rabbits, this wound dressing was shown to be efficacious in covering full-thickness and split-thickness skin defects. Finally, the efficacy of this wound dressing was evaluated in a nonrandomized open-label study of 31 clinical cases. In 31 cases treated with this wound dressing, good or excellent wound healing was achieved.  相似文献   
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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   
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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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