The increased operational tempo associated with current deployments to Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) is placing considerable strain on military families. Among other sequelae of OIF and OEF deployment, findings from recent studies suggest high rates of depression in spouses of service members. This review presents a rationale for targeting depression among military spouses. It examines how stressors relating to the deployment cycle may contribute to depression in spouses and outlines the effects of spousal depression on the mental health of service members and their children. Mental health services currently available to military spouses as well as barriers to their care are also described. Considerations for the adaptation of treatment to their unique circumstances and needs are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
Recent years have seen a drastic rise in the construction of web knowledge bases (e.g., Freebase, YAGO, DBPedia). These knowledge bases store structured information about real-world people, places, organizations, etc. However, due to the limitations of human knowledge, web corpora, and information extraction algorithms, the knowledge bases are still far from complete. To infer the missing knowledge, we propose the Ontological Pathfinding (OP) algorithm to mine first-order inference rules from these web knowledge bases. The OP algorithm scales up via a series of optimization techniques, including a new parallel-rule-mining algorithm, a pruning strategy to eliminate unsound and inefficient rules before applying them, and a novel partitioning algorithm to break the learning task into smaller independent sub-tasks. Combining these techniques, we develop a first rule mining system that scales to Freebase, the largest public knowledge base with 112 million entities and 388 million facts. We mine 36,625 inference rules in 34 h; no existing system achieves this scale.Based on the mining algorithm and the optimizations, we develop an efficient inference engine. As a result, we infer 0.9 billion new facts from Freebase in 17.19 h. We use cross validation to evaluate the inferred facts and estimate a degree of expansion by 0.6 over Freebase, with a precision approaching 1.0. Our approach outperforms state-of-the-art mining algorithms and inference engines in terms of both performance and quality. 相似文献
This article deals with powder metallurgical production and modification of properties of a composite material based on an age‐hardenable Al–Cu alloy. The main objective is to improve the mechanical properties by particle reinforcement and equal‐channel angular pressing (ECAP). Our approach makes use of four hardening mechanisms: precipitation hardening, particle reinforcement, strain‐hardening, and grain boundary hardening associated with an ultrafine‐grained microstructure produced by ECAP. The main processing steps are high‐energy ball milling, hot‐isostatic pressing, extrusion, heat treatment, and a single ECAP pass. Microstructures are analyzed by optical microscopy, scanning electron microscopy, and scanning transmission electron microscopy. The mechanical properties are characterized by hardness measurements and quasi‐static tensile testing. Our experimental results show that the proposed processing route results in a nearly homogeneous distribution of SiC particles in the matrix. The combination of particle reinforcement and ECAP leads to an improvement of ultimate tensile strength by almost 300 MPa compared to the unreinforced alloy. A subsequent heat treatment leads to a further increase in hardness and strength that can be related to changes in the defect structure. Our study provides detailed information on how processing steps, microstructures, and mechanical behavior are interrelated in this technologically relevant class of materials. 相似文献
The retrosplenial cortex (RSP) is highly interconnected with medial temporal lobe structures, yet relatively little is known about its specific contributions to learning and memory. One possibility is that RSP is involved in forming associations between multiple sensory stimuli. Indeed, damage to RSP disrupts learning about spatial or contextual cues and also impairs learning about co-occurring conditioned stimuli (CSs). Two experiments were conducted to test this notion more rigorously. In Experiment 1, rats were trained in a serial feature negative discrimination task consisting of reinforced presentations of a tone alone and nonreinforced serial presentations of a light followed by the tone. Thus, in contrast to prior studies, this paradigm involved serial presentation of conditioned stimuli (CS), rather than simultaneous presentation. Rats with damage to RSP failed to acquire the discrimination, indicating that RSP is required for forming associations between sensory stimuli regardless of whether they occur serially or simultaneously. In Experiment 2, a sensory preconditioning task was used to determine if RSP was necessary for forming associations between stimuli even in the absence of reinforcement. During the first phase of this procedure, one auditory stimulus was paired with a light while a second auditory stimulus was presented alone. In the next phase of training, the same light was paired with food. During the final phase of the procedure both auditory stimuli were presented alone during a single session. Control, but not RSP-lesioned rats, exhibited more food cup behavior following presentation of the auditory cue that was previously paired with light compared with the unpaired auditory stimulus, indicating that a stimulus-stimulus association was formed during the first phase of training. These results support the idea that RSP has a fundamental role in forming associations between environmental stimuli. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
Taking into consideration that DNA damage plays an important role in carcinogenesis, the purpose of this study was to evaluate
whether some radiopacifiers widely used in clinical practice are able to induce genetic damage in primary human cells in vitro.
Human peripheral lymphocytes obtained from 10 healthy volunteers were exposed to barium sulphate (BaSO4), zirconium oxide (ZnO2) and bismuth oxide (Bi2O3) at final concentrations ranging from 1 to 1000 μg/mL for 1 h at 37 °C. The negative control group was treated with vehicle
control (phosphate buffer solution) for 1 h at 37 °C and the positive control group was treated with hydrogen peroxide (at
100 μM) for 5 min on ice. Results were analyzed by the Friedman non-parametric test. The results pointed all compounds tested
out did not induce DNA breakage in human peripheral lymphocytes as depicted by the mean tail moment and tail intensity in
all concentrations tested. In summary, our results indicate that exposure to these radiopacifiers may not be a factor that
increases the level of DNA lesions in human peripheral lymphocytes as detected by single cell gel (comet) assay. 相似文献
The reaction of enamine compounds with disulfides in the presence of tert‐butyl hydroperoxide and a catalytic amount of tetrabutylammonium iodide conveniently afforded a variety of α‐thioenamine compounds through the intermolecular oxidative C(sp2) S coupling. Incorporating both of the sulfide moieties in the disulfides into the final products under oxidative conditions, this novel approach exhibits the feature of atom efficiency. A radical mechanistic pathway for the reaction process has been proposed.
A domino reaction of palladium(II)‐catalyzed dual C–H functionalization with subsequent intramolecular annulation is presented. This method provides a convenient synthesis of a range of symmetrical and unsymmetrical biologically important (E)‐bisindole‐2‐ones under extremely mild reaction conditions – room temperature, green oxidant and no additive. The reaction mechanism is elucidated in light of the yield values as well as additional control experiment results.
Porous silicon (PS) layers were formed on p-type, 〈1 0 0〉 oriented, 1-5 Ω cm resistivity Cz silicon wafers by electrochemical etching in an HF:C2H5OH (1:2 by volume) electrolyte at room temperature at a constant current density 20 mA/cm2. The etching duration was varied to achieve PS layers of different morphologies and thicknesses. Both the photoluminescence (PL) and the total diffused reflectivity spectra of the PS layers were measured. It was found that for the PS layers grown for etching durations of less than 90 s the PL emission is insignificant and reflectivity is quite low. Such PS layers can be used as antireflection coatings (ARC) on solar cells. The PS layers formed for etching durations greater than 90 s show a significant PL emission in 500-800 nm range with peak lying in 630-660 nm wavelength range. When etching duration increases from 90 s to 8 min the PL intensity increases and the PL peak shows a blue shift. With further increase in etching duration the PL intensity decreases and PL peak shows a red shift. The reflectivity of the photoluminescent layers increases with etching duration showing a highest value for a sample grown for 8 min. Further increase in etching duration up to 20 min the reflectivity decreases and then increases. Striking observation is that both the PL emission intensity and reflectivity in the wavelength range of 550-800 nm are maximum for the PS layer grown for the etching duration of 8 min. 相似文献