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1.
Lymphocyte subpopulations were studied in 31 men working in a plant producing plastic materials in relation with control groups of similar age and smoking habit. 8 workers (group A) were exposed to solvents (mainly methylethylketone and dimethylformamide), 8 men (group B) to dust containing particles of calcium carbonate, polyvinylchloride, phtalates, unsaturated oils, paraffin wax, iron oxides, titanium bioxides, barium, zinc and lead and 15 men (group C), working in the same department as group B, were studied after a period of 16 months during which lead chromate was employed in the preparation of colors. The lymphocyte subpopulations were normal in group A, while in B there was a significant increase of HLA-DR + cells (monocytes, B and activated T lymphocytes). In group C, T helper/inducer lymphocytes (mainly CD4(+)-CD45RO- "virgin" lymphocytes), CD19+ B lymphocytes, CD3-HLADR+ and CD3-CD25+ (activated B lymphocytes and monocytes) were significantly reduced without changes of serum IgM, IgG and IgA. Highly significant correlation was found between B lymphocytes (reduced in the workers about 40%) and CD4(+)-CD45R0+ "memory" lymphocytes (reduced about 20%). Moreover, blood lead (correlated with urinary chromium) showed a highly significant negative correlation with the B lymphocytes. This study demonstrates that combined exposure to toxic agents produces specific modifications in the lymphocyte subsets without changes in immunoglobulins and confirms the results of previous researches showing that the exposure to lead or chromate induces reduction of lymphocytes in the peripheral blood.  相似文献   
2.
Combined in situ, model, and satellite remote-sensing observations are used to determine the location of the Gulf Stream as an aid to safe navigation for small recreational vessels.

A field study was executed from Hamilton, Bermuda, to Virginia Beach, USA, over a period of 5 days, from 30 June 2010 to 4 July 2010 to test the feasibility of using remote-sensing products as an aid to cross the Gulf Stream from the point of view of a small, slow-moving (?6 knots, 3 m s?1) sailboat. The in situ data collected were compared to NASA Moderate Resolution Imaging Spectroradiometer (MODIS) and Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) remote-sensing data, to the Global High Resolution Sea Surface Temperature (GHRSST) microwave and infrared blended data set, to the National Oceanic and Atmospheric Administration Real-Time Ocean Forecast System (NOAARTOFS) ocean model, and to selected NOAA buoy and ship measurements.

A spatio-temporal analysis was performed by comparing the in situ measurements with observations retrieved at the same time and location in each of the data sets. The least error (correlation coefficient r?=?0.94) was obtained using MODIS data, and the largest error (r?=?0.78) was obtained using the RTOFS model data. Overall, most observations agree with the general spatio-temporal trend of the in situ data, with 95% of the errors within ±1°C and 98% of the errors within ±2°C.

The study shows that MODIS data are particularly suited to identification of the location of the Gulf Stream, which can be used by small vessels to optimize the crossing route and to minimize the risks associated with the passage.  相似文献   
3.
The pgip-1 gene of Phaseolus vulgaris, encoding a polygalacturonase-inhibiting protein (PGIP), PGIP-1 (P. Toubart, A. Desiderio, G. Salvi, F. Cervone, L. Daroda, G. De Lorenzo, C. Bergmann, A. G. Darvill, and P. Albersheim, Plant J. 2:367-373, 1992), was expressed under control of the cauliflower mosaic virus 35S promoter in tomato plants via Agrobacterium tumefaciens-mediated transformation. Transgenic tomato plants with different expression levels of PGIP-1 were used in infection experiments with the pathogenic fungi Fusarium oxysporum f. sp. lycopersici, Botrytis cinerea, and Alternaria solani. No evident enhanced resistance, compared with the resistance of untransformed plants, was observed. The pgip-1 gene was also transiently expressed in Nicotiana benthamiana with potato virus X (PVX) as a vector. PGIP-1 purified from transgenic tomatoes and PGIP-1 in crude protein extracts of PVX-infected N. benthamiana plants were tested with several fungal polygalacturonases (PGs). PGIP-1 from both plant sources exhibited a specificity different from that of PGIP purified from P. vulgaris (bulk bean PGIP). Notably, PGIP-1 was unable to interact with a homogeneous PG from Fusarium moniliforme, as determined by surface plasmon resonance analysis, while the bulk bean PGIP interacted with and inhibited this enzyme. Moreover, PGIP-1 expressed in tomato and N. benthamiana had only a limited capacity to inhibit crude PG preparations from F. oxysporum f. sp. lycopersici, B. cinerea, and A. solani. Differential affinity chromatography was used to separate PGIP proteins present in P. vulgaris extracts. A PGIP-A with specificity similar to that of PGIP-1 was separated from a PGIP-B able to interact with both Aspergillus niger and F. moniliforme PGs. Our data show that PGIPs with different specificities are expressed in P. vulgaris and that the high-level expression of one member (pgip-1) of the PGIP gene family in transgenic plants is not sufficient to confer general, enhanced resistance to fungi.  相似文献   
4.
Tested the hypothesis that self-evaluative and self-efficacy mechanisms mediate the effects of goal systems on performance motivation. These self-reactive influences are activated through cognitive comparison requiring both personal standards and knowledge of performance. 45 male and 45 female undergraduates performed a strenuous activity with either goals and performance feedback, goals alone, feedback alone, or without either factor. The condition combining performance information and a standard had a strong motivational impact, whereas neither goals alone nor feedback alone effected changes in motivation. When both comparative factors were present, the evaluative and efficacy self-reactive influences predicted the magnitude of motivation enhancement. The higher the self-dissatisfaction with substandard performance and the stronger the perceived self-efficacy for goal attainment, the greater was the subsequent intensification of effort. When one comparative factor was lacking, the self-reactive influences were differentially related to performance motivation, depending on the nature of the partial information and on the type of subjective comparative structure imposed on the activity. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
Comments on L. R. Goldberg's (see record 1993-17546-001) depiction of the Big Five factor structure as an alternative theoretical perspective on personality. In light of the multiple perspectives that characterize personality psychology, it is asserted that Goldberg's remarks about an emerging consensus on the Big Five as a solution should be read with caution. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
Remote-sensing satellite data are routinely used during disasters for damage assessment and to coordinate relief operations. Although there is a plethora of satellite sensors able to provide actionable data about an event, their temporal resolution is limited by their revisit time, presence of clouds, and errors in the reception of data. These limitations do not allow for an uninterrupted monitoring, which is crucial during disasters and emergencies. This research presents an approach that leverages the increased temporal resolution of crowdsourced data to partially overcome the limitations of satellite data. The proposed approach focuses on the geostatistical analysis of a combined satellite and Twitter data to help delineate the flood extent on a daily basis. The crowdsourced data are used to augment satellite imagery from Advanced Land Imager instrument on Earth Observating One (EO-1) satellite, Landsat 8, WorldView-2, and WorldView-3. The proposed methodology was applied to estimate the daily flood extents in Charleston, South Carolina, caused by the October 2015 North American storm complex. The results of the proposed methodology indicate that the user-generated data can be utilized adequately to both bridge the temporal gaps in the satellite-based observations and also increase the spatial resolution of the flood extents.  相似文献   
7.
Examined the effects of induced mood on personal standards for performance and judgments of one's performance capabilities, or self-efficacy judgments. Three experiments involving 208 undergraduates were conducted. In Exp 1, standards and self-efficacy judgments were assessed on common social and academic tasks. In Exp 2, these variables were assessed on 2 novel tasks. In both experiments, negative mood induced higher standards for performance. Induced mood had no effect on perceived self-efficacy. Negative mood Ss thus held minimal standards for performance that significantly exceeded the levels of performance they judged they actually could attain. Exp 3 provided support for the hypothesis that negative mood raises standards by lowering evaluations of prospective outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
A genetic algorithm is paired with a Lagrangian puff atmospheric model to reconstruct the source characteristics of an atmospheric release. Observed meteorological and ground concentration measurements from the real-world Dipole Pride controlled release experiment are used to test the methodology. A sensitivity study is performed to quantify the relative contribution of the number and location of sensor measurements by progressively removing them. Additionally, the importance of the meteorological measurements is tested by progressively removing surface observations and vertical profiles. It is shown that the source term reconstruction can occur also with limited meteorological observations. The proposed general methodology can be applied to reconstruct the characteristics of an unknown atmospheric release given limited ground and meteorological observations.  相似文献   
9.
Objectives: Nearly all smokers who lapse experience a full-blown relapse, but the mediating mechanisms that contribute to this relationship are not well understood. A better understanding of these mechanisms would help to advance more effective relapse prevention treatments for smokers. The purpose of this study is to experimentally evaluate the effects of a programmed smoking lapse on smoking relapse and the effects of postlapse changes in craving on relapse. Method: Adult smokers (n = 63) who quit smoking with a brief cognitive–behavioral intervention and self-help materials were randomly assigned to one of two experimental conditions after 48 h of abstinence: No lapse (a no-smoking control/30-min waiting period) or lapse (smoking two cigarettes of their favored brand during a 30-min period). All participants were then followed daily for 14 days. Craving and biochemically verified self-reported abstinence were assessed on each follow-up day. Time (days) to relapse (7 consecutive days of smoking) was the main dependent measure. Results: Results of Cox regression analysis revealed that participants in the lapse condition relapsed more quickly than participants in the no-lapse condition (hazard ratio [HR] = 2.12, 95% confidence interval [CI] = [1.03, 4.35]). These effects were attributable, in part, to episodic increases in craving among participants in the lapse condition only (HR = 12.42, 95% CI =[2.00, 77.1]). Conclusions: Previously abstinent smokers who lapse are at risk for increased cigarette cravings and consequently, full-blown relapse. These results have implications for both cognitive–behavioral treatments for relapse prevention and for medications designed to help smokers manage cravings. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
10.
This article presents a theoretical framework for analyzing psychological systems that contribute to the variability, consistency, and cross-situational coherence of personality functioning. In the proposed knowledge-and-appraisal personality architecture (KAPA), personality structures and processes are delineated by combining 2 principles: distinctions (a) between knowledge structures and appraisal processes and (b) among intentional cognitions with varying directions of fit, with the latter distinction differentiating among beliefs, evaluative standards, and aims. Basic principles of knowledge activation and use illuminate relations between knowledge and appraisal, yielding a synthetic account of personality structures and processes. Novel empirical data illustrate the heuristic value of the knowledge/appraisal distinction by showing how self-referent and situational knowledge combine to foster cross-situational coherence in appraisals of self-efficacy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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