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11.
In this study, we evaluate the use of riparian tree‐geometry and bank‐characteristic data in developing riverbank stability forecasts at four study sites along a mercury‐contaminated reach of the South River, Virginia. Our forecast data set includes measurements of tree diameter, lean angle and percent root‐plate undercut, coupled with bank characteristics included in the Pfankuch Index. Stepwise comparisons and statistical analyses of our tree‐geometry data reveal that lean angle and percent root‐plate undercut are effective measures for discriminating between riparian tree populations at eroding and stable banks, with the strongest discriminant power from the percent root‐plate undercut. Our stability forecasts, using both tree and bank characteristics, agree with long‐term observations, underscoring the value of rarely used tree‐geometry data in such evaluations. The application of these results is important in long study reaches where forecasts of erosion potential from contaminated banks are required to develop mitigation strategies, but direct measurements of bank stability are not feasible. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
12.
We describe a program for the display and exploration of complex, domain-specific information: ytracc, an interactive grammar debugging tool for compiler writers. The ytracc system provides the designer of a yacc grammar a method of tracing a parser as it uses the grammar, ytracc captures the states of the parse as it is carried out. The captured parse can then be replayed forwards or backwards, step-by-step, or subtree-by-subtree, as defined by the non-terminals of the grammar. The tool has been successfully used by students as an assistant in an advanced undergraduate compiler construction class, and we use the tool in our everyday work.  相似文献   
13.
These are exciting times in nursing, with great possibilities for reforming nursing as we now know it. The desired outcome is to improve any nurse's ability to care for individuals, families, and communities wherever they are. We believe that articulating CBN and CHN practice is a necessary first step in achieving this outcome; however, it now becomes our challenge to advance this vision. We ask you to join us in this endeavor.  相似文献   
14.
Gender data for bupropion suggest that it may be a particularly effective smoking cessation medication for women. It is not known whether the efficacy of this pharmacotherapy differs as a function of the psychotherapy with which it is administered. This study used a two level factorial design to examine the independent and interactive effects of medication (bupropion 300 mg/day vs. placebo) and psychotherapy (cognitive-behavioral therapy [CBT] vs. supportive therapy [ST]). In addition to testing the hypothesis that bupropion with CBT would be most effective of all the treatments, we examined medication compliance and its role in the efficacy of bupropion. Participants were 154 women, aged at least 30 years and smoking more than 10 cigarettes/day. Compliance with study medication was assessed using Medication Event Monitoring Systems (MEMS) over 7 weeks of treatment. Psychological interventions were delivered in 60-min weekly group sessions. Longitudinal analysis of abstinence outcomes from end of treatment (EOT) through 12 months after treatment revealed a significant interaction of medication and therapy. Higher abstinence rates at EOT and 3-, 6-, 9-, and 12-month follow-ups were observed when bupropion was delivered concurrently with CBT (44%, 24%, 30%, 23%, 17%) rather than with ST (18%, 1%, 8%, 5%, 2%). The bupropion-CBT combination, however, was not clearly superior to placebo, regardless of therapy assignment. Higher rates of medication compliance were positively predictive of abstinence, and this effect was most evident in the placebo condition. Findings provide only modest support for CBT as the preferred type of intensive therapy in conjunction with bupropion in women.  相似文献   
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16.
There is a growing need for the inclusion of nonvolatile memory within implantable medical devices in order to store product identification, operating parameters, calibration information, as well as patient and diagnostic data. Due to the critical nature of the application however, the data retention reliability is of utmost importance. In the case of nonvolatile memories, a source of concern regards their exposure to ionizing radiation as the result of diagnostic or therapeutic procedures performed on the patient. This paper reports on X- and gamma-ray experiments and calculations on a representative modern electrically erasable and programmable read-only memory (EEPROM) (Atmel 24C64). No transient upsets due to 150 kVp X-rays were observed in 10 unbiased and five biased DTU's up to the maximum achievable 27 rad(Si)/s for a total dose of 200 rad(Si). Unbiased parts had no failure to an average total-dose of 40.9 krad(Si). The lowest failure level observed for an unbiased part was 30.0 krad(Si). In the biased parts, the read-mode operating current increased as a function of total dose from 47 μA prior to exposure to 385 μA at 30 krad(Si). The mean highest no-failure level for 10 unbiased parts exposed to Co60 gamma-rays was 36.9 krad(Si) with a sigma of 2.3. Five biased DUT failures occurred at a mean of 27.84 krad(Si) with a sigma of 2.42. The analysis of these data, in comparison to maximum therapeutic photon radiation doses suggest that floating-gate EEPROM technology is reliable in the presence of photon ionizing-radiation exposures typical of medical diagnostic and therapeutic environments  相似文献   
17.
Little research has examined the healing and pain associated with saphenous vein (SV) harvest incisions, and no literature has addressed the associated distress and cosmetic result. The purpose of this study was to determine whether dry sterile gauze dressings, transparent film dressings or no dressings were more effective in hospitalized patients undergoing coronary artery bypass graft (CABG), in terms of minimizing leg incisional pain, minimizing the distress of a leg scar and improving the cosmetic appearance of the leg incision scar. Patients were randomized to dressing type on postoperative day (POD) 1, completed a pain and distress visual analogue scale (VAS) on PODs 1, 3 and 5, and a cosmetic result VAS upon discharge. Overall, leg incisional pain decreased over time (p < 0.05). Females reported decreasing pain between PODs 1 and 3, while males reported increasing pain between PODs 1 and 3 (p < 0.05). The film-dressing group reported decreasing pain from PODs 1 to 3, while the no-dressing and gauze-dressing groups reported increasing pain from PODs 1 to 3 (p < 0.05). Pain on POD 5 was positively correlated with an unfavorable cosmetic result (r = 0.42, p < 0.05), and distress on POD 5 was positively correlated with an unfavorable cosmetic result (r = 0.44, p < 0.05). The results of this study are encouraging and support the continued testing of dressings to minimize pain and distress, as well as enhancing cosmetic result.  相似文献   
18.
Mice, rats and guinea pigs were exposed to phosgene (COCl2), a highly irritating and oxidizing gas. Animals were exposed to 87 mg/m3 phosgene for 20 min in a whole-body exposure chamber. Within 55-65 minutes after the start of exposure, plasma was scanned spectrophotometrically from 200-600 nm. A distinct and significant increase in area under the curve in the Soret band region at 413 nm was observed in plasma from phosgene-exposed animals when compared with air-exposed controls in all three species. These peaks were consistent with hemoglobin, an indication that the integrity of the erythrocyte membrane had been compromised by exposure. An erythrocyte osmotic fragility assay on blood from mice exposed to phosgene indicated that 30% less NaCl was needed to cause 50% hemolysis compared to air-exposed mice. These results suggest a new mechanism of phosgene-induced acute lung injury that may be linked, in part, to a direct attack on the erythrocyte membrane.  相似文献   
19.
This study examined the process of change in pregnancy smoking cessation, using the stages and processes of change from the Transtheoretical Model, to compare women who stopped smoking during pregnancy with women who were in the process of smoking cessation, but were not pregnant. Differences in smoking cessation process activity and abstinence self-efficacy were hypothesized between the pregnant and nonpregnant groups of women. Study participants were 89 pregnant women who quit smoking, 28 nonpregnant women in the action stage of smoking cessation, and 92 nonpregnant women in the preparation stage. The Smoking Cessation Processes of Change Scale and the Smoking Abstinence Self-Efficacy Scale served as dependent measures. One-way MANOVA and follow-up Newman-Keuls comparisons indicated significant differences between pregnant and nonpregnant women in their levels of process activity and self-efficacy. Pregnancy smoking cessation differed dramatically from the process of nonpregnancy smoking cessation. Pregnant quitters were not engaging in experiential and behavioral processes at levels associated with the action stage of change. Low levels of process use and high efficacy indicated an externally (for the baby) motivated stopping rather than an internal, intentional process of change, which may account for high relapse rates postpartum.  相似文献   
20.
A single-chip pacemaker chip has been developed which integrates high-level sampled-data analog functions on the same chip with an 8-bit microcomputer. It uses circuit techniques to reduce power and insure long-term stability. Current-drain is typically 8 μA and minimum operating voltage is 1.7 V. The chip is described in the context of the systems choices available in design implantable medical devices  相似文献   
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