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91.
This study of continuing care for substance dependent patients compared a telephone-based monitoring and brief counseling intervention (TEL) with 2 face-to-face interventions, relapse prevention (RP) and standard 12-step group counseling (STND). The participants were graduates of intensive outpatient programs who had current dependence on alcohol and/or cocaine. Self-report, collateral, and biological measures of alcohol and cocaine use were obtained over a 12-month follow-up. The treatment groups did not differ on abstinence-related outcomes in the complete sample (N = 359) or on cocaine use outcomes in participants with cocaine dependence (n = 268). However, in participants with alcohol dependence only (n = 91), TEL produced better alcohol use outcomes than STND on all measures examined and better outcomes than RP on some of the measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
92.
Objective: Examine longitudinal relationships between causal attributions and depression symptoms in adults with rheumatoid arthritis (RA). Study Design: Cross-lagged panel correlations tested the temporal precedence of attributions relative to depression symptoms over 1 year. Participants: Forty-two participants completed self-report instruments on 2 occasions. Main Outcome Measures: The Inventory to Diagnose Depression and the Attributional Style Questionnaire. Results: Time 1 attributions predicted increased levels of depression symptoms at Time 2 after perceived pain and disability were controlled: Time 1 depression symptoms were unrelated to Time 2 attributions. Cross-lagged correlation comparisons revealed statistical dominance for attribution-depression relationships relative to depression-attribution relationships. Conclusions: Results support cognitive diathesis conceptualizations of depression and support cognitive-behavioral treatments for depression in RA. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
93.
With the deployment of native multicast in commercial networks, multicast is getting closer to becoming a ubiquitous service in the Internet. The success of this deployment largely depends on the availability of good management tools and systems. One of the most important management tasks for multicast is to verify the availability of the service to its users. This task is usually referred to as reachability monitoring. Reachability monitoring requires a number of monitoring stations to work together to collect this information in a distributed manner in the interdomain scale. In this paper we present a general architecture for multicast reachability monitoring systems and focus on three critical functions: agent configuration, monitoring, and feedback collection. For each component, we provide a number of alternative approaches to implement the required functionality and discuss their advantages and disadvantages. Then, we focus on the feedback collection component. To a large extent, it determines the complexity and the overhead of a monitoring system. Using simulations, we compare a number of alternative approaches for feedback collection and make suggestions on when to use each. We believe our work provides insight into the issues and considerations in designing and developing multicast reachability monitoring systems.  相似文献   
94.
The authors compared longitudinal treatment outcomes for depressed substance-dependent veterans (N = 206) assigned to integrated cognitive–behavioral therapy plus standard pharmacotherapy (ICBT + P) or 12-step facilitation therapy plus standard pharmacotherapy (TSF + P). Drug and alcohol involvement and depressive symptomology were measured at intake and at 3-month intervals during treatment and up to 1 year posttreatment. Participants in both treatment conditions showed decreased depression and substance use from intake. ICBT + P participants maintained improvements in substance involvement over time, whereas TSF + P participants had more rapid increases in use in the months following treatment. Decreases in depressive symptoms were more pronounced for TSF + P than ICBT + P in the 6 months posttreatment. Within both treatment groups, higher attendance was associated with improved substance use and depression outcomes over time. Initial levels of depressive symptomology had a complex predictive relationship with long-term depression outcomes. Early treatment response predicted long-term substance use outcomes for a portion of the sample. Although both treatments were associated with improvements in substance use and depression, ICBT + P may lead to more stable substance use reductions compared with TSF + P. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
95.
96.
In this study,perforated cannulated magnesium(Mg)hip stents were fabricated via modified Mg injection molding and conventional machining,respectively.Additionally,the stent canal was filled with paraffin to simulate injection of biomaterials.The microstructure,mechanical performance,corrosion behavior,and biocompatibility were comparably studied.Scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS)showed higher affinity of interstitial element such as oxygen and carbon as consequences of routine molding process.After immersion in SBF,machining stents showed reduced degradation rate and increased deposition of calcium phosphate compared to molding stents.Corrosion resistance was improved via paraffin-filling.Consistently,the hemolysis and in vitro osteoblast cell culture models showed favourable biocompatibility in machining stents compared to molding ones,which was improved by paraffin-filling treatment as well.These results implied that the feasibility of the prepared machining stents as the potential in vivo orthopaedic application where slower degradation is required,which could be enhanced by designing canal-filling injection of biomaterials as well.  相似文献   
97.
Zhou  Hongzhen  Wang  Shuyuan  Zhang  Tao  Liu  Demei  Yang  Kevin 《The Journal of supercomputing》2021,77(4):4151-4171

The purpose of this study was to explore the value of extraction of tumor features in contrast-enhanced ultrasonography (CEUS) images based on the deep belief networks (DBN) for the diagnosis of cervical cancer patients and realize the intelligent evaluation on effects of diagnosis and chemotherapy of the cervical cancer. An automatic extraction algorithm with the time-intensity curve (TIC) was proposed based on Sparse nonnegative matrix factorization (SNMF) in this study, and was applied to the framework of automatic analysis of cervical cancer tumors based on the deep belief networks, to assist doctors in the analysis of cervical cancer tumors. The framework was applied to the real clinical diagnostic data, and the feasibility of the method was verified by comparing the accuracy, sensitivity, and specificity. Later, the parameters of patients’ time to peak (TP), peak intensity (PI), mean transit time (MTT), and area under the curve (AUC) were obtained by drawing TICs, and the changes of p53 protein and ki-67 protein obtained by pathological section staining were analyzed to evaluate the therapeutic effect in the patients. It was found that the proposed model of tumor feature extraction based on the DBN had the higher accuracy (86.36%), sensitivity (83.33%), and specificity (87.50%). The related parameters of TIC curve obtained based on SNMF showed that there was a significant difference in p53 content between tissues with different degrees of disease (p?<?0.05), the PI of poorly differentiated tissues was significantly higher than that of those with high to medium differentiation (p?<?0.05). In addition, PI and AUC of patients after chemotherapy were significantly lower than that before chemotherapy (p?<?0.05), while MTT was significantly higher than that before chemotherapy (p?<?0.05). Therefore, the proposed TIC feature extraction of CEUS images based on SNMF and the automatic tumor classification based on deep learning can be used in the diagnosis and efficacy evaluation of cervical cancer patients.

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98.
While enjoying various LBS (location‐based services), users also face the threats of location privacy disclosure. This is because even if the communications between users and LBS providers can be encrypted and anonymized, the sensitive information inside LBS queries may disclose the exact location or even the identity of a user. The existing research on location privacy preservation in mobile peer‐to‐peer (P2P) networks assumed that users trust each other and directly share location information with each other. Nonetheless, this assumption is not practical for most of the mobile P2P scenarios, for example, an adversary can pretend to be a normal user and collect the locations of other users. Aiming at this issue, this paper presents x‐region as a solution to preserve the location privacy in a mobile P2P environment where no trust relationships are assumed amongst mobile users. The main idea is to allow users to share a blurred region known as x‐region instead of their exact locations so that one cannot distinguish any user from others inside the region. We propose a theoretical metric for measuring the anonymity property of x‐region, together with three algorithms for generating an x‐region, namely, benchmark algorithm, weighted expanding algorithm, and aggressive weighted expanding algorithm. These algorithms achieve the anonymity and QoS requirements with different strategies. Our experiments verify the performance of the algorithms against three key metrics. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
99.
The ability of evolution to shape organic form involves the interactions of multiple systems of constraints, including fabrication, phylogeny and function. The tendency to place function above everything else has characterized some of the historical biological literature as a series of ‘Just-So’ stories that provided untested explanations for individual features of an organism. A similar tendency occurs in biomaterials research, where features for which a mechanical function can be postulated are treated as an adaptation. Moreover, functional adaptation of an entire structure is often discussed based on the local characterization of specimens kept in conditions that are far from those in which they evolved. In this work, environmental- and frequency-dependent mechanical characterization of the shells of two cephalopods, Nautilus pompilius and Argonauta argo, is used to demonstrate the importance of multi-scale environmentally controlled characterization of biogenic materials. We uncover two mechanistically independent strategies to achieve deformable, stiff, strong and tough highly mineralized structures. These results are then used to critique interpretations of adaptation in the literature. By integrating the hierarchical nature of biological structures and the environment in which they exist, biomaterials testing can be a powerful tool for generating functional hypotheses that should be informed by how these structures are fabricated and their evolutionary history.  相似文献   
100.
Medication adherence—taking medication as prescribed—is critical for successful self-care, especially among older adults. Adherence depends on developing and implementing plans for taking medications. Age-related cognitive declines that affect adherence may be mitigated using external tools that support patient-provider collaboration needed to develop these adherence plans. We tested the effectiveness of structured collaborative medication tools to support better medication planning and adherence practices. Evidence for benefits of collaborative tools has been mixed in terms of their usefulness for medication-scheduling tasks, perhaps because the tools have not been explicitly designed to support patient-provider collaboration. A total of 144 community-dwelling older adults participated in pairs and performed the role of a patient or provider in a simulated patient-provider medication-scheduling task. Each pair worked with a structured (MedTable? and e-MedTable) or unstructured (Medcard) scheduling tool and completed four problems (2 simple and 2 complex). Performance was measured using the following: problem-solving (medication schedule) accuracy, problem-solving time, solution (schedule) optimality, tool usability, collaborative effectiveness, and subjective workload involved in creating the medication schedules. Participants using structured tools produced more accurate and optimal schedules. They also rated subjective workload as lower and thought that the structured tools were easier to use, reduced subjective workload associated with creating the schedules. There was also suggestive evidence that participants using the structured tools rated more highly the quality of their collaboration. Structured medication-scheduling tools have the potential to improve medication adherence among older adults because they support collaborative planning and reduce the cognitive load involved in creating these adherence plans.  相似文献   
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