Cystic duct syndrome and minimally invasive surgery

Cholecystectomy is an established successful operation which provides total relief of presurgical symptoms in up to 85% of patients. About 5% of patients after cholecystectomy experience severe episodes of upper abdominal pain, similar to those that they had prior to cholecystectomy. These so called postcholecystectomy syndromes may be due to biliary strictures, retained biliary calculi, cystic duct stump syndrome, stenosis or dyskinesis of the sphincter of Oddi. Postcholecystectomy symptoms caused by cystic stump and gallbladder remnant had been described early in this century and several papers have been published on the topic. During recent years laparoscopic cholecystectomy became popular but we have not found in the literature the mention of either that it could cause cystic duct stump syndrome or it could be used for its treatment. During the last seven years in 8 patients we found gallbladder remnants or cystic duct stumps causing their symptoms. Among the 8 patients 3 had laparoscopic and 5 classic cholecystectomies. After incomplete cholecystectomy we usually find that the cystic duct stump and the Calot triangle embedded in inflamed scar tissue. For this reason the surgical risk is to high with laparoscopic surgery to reoperate for these pathological changes. In all 8 cases the pathological cystic duct stumps and gallbladder remnants were removed using 3-4 cm single microlaparotomy incisions. The postoperative stay of these patients were uneventful and they were discharged home 2-3 days after surgery.     

Composition, process, and performance in self-managed groups: The role of personality.

Using the five factor model with an emphasis on extraversion and conscientiousness, the authors investigated how personality is related to small group processes and outcomes. Graduate students (N ?=?289) assigned to 4- and 5-person teams in 61 groups engaged in a series of creative problem-solving tasks over a period of several weeks. Extraversion was associated with group processes and outcomes at both individual and group levels of analysis. At the individual level, extraverts were perceived by others as having greater effect than introverts on group outcomes. Covariance structure modeling suggested that extraverts induce these perceptions through the provision of both socioemotional and task-related inputs. At the group level, the proportion of relatively extraverted members was related curvilinearly to task focus and group performance. Contrary to expectations, Conscientiousness was unrelated to processes and outcomes at either the individual or group level. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modeling of Lake Ice Characteristics in North America Using Climate, Geography, and Lake Bathymetry

Ice cover records from 128 freshwater lakes in the United States and Canada were analyzed. Multivariable linear regression models, log-transform models, and a combination of the two (the “hybrid” form) were used to express ice-in date, ice-out date, and maximum ice thickness as functions of mean air temperature, latitude, average depth, elevation, and surface area of each lake. Mean air temperatures are for periods from September 1 to December 31 for ice-in dates, February 1 to June 30 for ice-out dates, and September 1 to June 30 for maximum ice thickness. Data for individual years as well as averages (over the record length) for each lake were analyzed. The log-transform formulas proved best for estimating ice-in date, while the hybrid form provided the best models of maximum ice thickness. The linear regression model estimated the ice-out date best. In most cases, mean air temperature and/or latitude were the most influential parameters, followed by elevation. Lake surface area and depth had a small or no influence. R2 values of all equations ranged from 0.50 to 0.92.     

Incorporating biomarkers of exposure and genetic susceptibility into smoking cessation treatment: Effects on smoking-related cognitions, emotions, and behavior change.

In this article the authors report on the short-term impact of incorporating biomarker feedback about exposure and genetic susceptibility into minimal-contact quit-smoking counseling (QSC). Four hundred and twenty-seven smokers were randomized to 1 of 3 treatments: (a) QSC, (b) QSC + exposure biomarker feedback (EBF) about carbon monoxide in exhaled breath, or (b) QSC + EBF + biomarker feedback about genetic susceptibility to lung cancer (SBF). We observed significant immediate positive effects of SBF, compared with EBF and QSC, on perceived risk, perceived quitting benefits, and fear arousal. However, at the 2-month follow-up, there were no group differences in quit rates. SBF did lead to significant reductions in the number of cigarettes smoked for smokers who were in the preparation stage. Smokers in the EBF and QSC conditions showed reductions in depressive symptoms by 2 months, but smokers in the SBF condition did not. In the context of QSC, genetic feedback may heighten vulnerability and possibly promote distress, but may not immediately enhance quitting in most smokers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

水平定向钻进帮助新南威尔士扩大自来水供应

本文简要介绍了在Shannon Creek的储存设施工程采用水平定向钻进施工的情况。     

演进的可编程网络

过去30年来,通信产业经历了重大的变革,很大程度上,业务模式从提供有线宽带转变为随时随地提供无缝的互联网和应用接入。这种转变主要得益于半导体技术的持续创新以及光传输和无线传输技术的改进,从而带来了更快、更便宜的带宽。如今,正在迈入由云计算和数以万亿计的全新互联设备所驱动的行业新纪元——万物互联。这就意味着电信运营商如果想在未来取得成功,必须要在业务模式、网络架构和技术方面做出改变。对这些产业趋势进行了分析,剖析了如何实现网络创新,以满足这些新兴要求以及帮助电信运营商实现其业务目标。     

Instar and outstar learning with memristive nanodevices

The instar and outstar synaptic models are among the oldest and most useful in the field of neural networks. In this paper we show how to approximate the behavior of instar and outstar synapses in neuromorphic electronic systems using memristive nanodevices and spiking neurons. Memristive nanodevices are especially attractive for this application since such devices are tiny, can be densely packed in crossbar-like structures and possess the long time constants, or memory, needed by the synaptic models.     

Application of synthetic fluid inclusions to simultaneous temperature–pressure logging in high-temperature (sub- to supercritical) geothermal systems

Batch-autoclave experiments have been conducted to evaluate the potential use of synthetic fluid inclusions as a simultaneous temperature–pressure (and fluid sampling) logging tool in deep-seated, high-temperature (>350 °C) geothermal systems. The application of synthetic fluid inclusions allows us to obtain information about thermal-pressure conditions in deep-seated geothermal systems, where conventional tools cannot be used because of the extreme temperature conditions. Fluid inclusions, up to 50 μm long, have been readily synthesized during 5-day autoclave experiments (conducted at 375–475 °C and 39–62 MPa) in pre-fractured, inclusion- and impurity-free artificial quartz. Inferred fluid inclusion (temperature–pressure) trapping conditions are calculated by deducing the intersection of isochores derived from microthermometric data for three sets of simultaneously trapped synthetic fluid inclusions in healed microfractures. Synthetic fluid inclusion logging offers a precise borehole temperature measurement technique without need of any pressure correction. Pressure estimates are less precise, although the method may be improved by using a combination of H₂O–NaCl and H₂O–KCl solutions/salinities, and fluid/quartz/amorphous silica systems that facilitate crack healing but trap fluids that do not homogenize at near-critical conditions.