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1.
The total number of computer monitors being scrapped per year worldwide is predicted to rise to 30 million units by the year 2005. Monitors contain significant quantities of lead (in the solder and CRT glass) and polybrominated flame retardants, which are potentially hazardous if released to the environment. A recent study investigated the possibility of cost-effectively recycling monitors  相似文献   
2.
OBJECTIVE: To examine the impact of central adiposity upon hemodynamic functioning at rest and during stress in adolescents. DESIGN: Cross-sectional, correlational study. SUBJECTS: 46 White and 49 Black normotensive adolescents with family histories of essential hypertension. MEASUREMENTS: Systolic and diastolic blood pressure (SBP, DBP), cardiac output and total peripheral resistance responses were assessed at rest, during postural change, video game challenge and forehead cold stimulation. Specific lower and higher waist-to-hip ratio (WHR) tertiles were created for each gender and then integrated for analyses. This resulted in a lower WHR tertile of 11 Whites and 21 Blacks and an upper WHR tertile of 15 Whites and 17 Blacks. RESULTS: No differences in age, gender or ethnicity proportions were found between tertile groups (all P > 0.21). The upper WHR group showed greater body weight, waist and hip circumferences, body mass index (BMI), triceps skinfold and body surface area (all P < 0.001). Controlling for peripheral (that is, triceps skinfold) and overall (that is, BMI) adiposity, the upper WHR group exhibited greater SBP (that is, peak response minus mean pre-stressor level) to all three stressors and greater DBP reactivity to postural change and cold pressor (all P < 0.05). CONCLUSION: Central adiposity appears to adversely influence hemodynamic functioning during adolescence. Underlying mechanisms responsible for these associations require exploration.  相似文献   
3.
An algorithm is presented in this paper to facilitate the exploration of large image collections based on visual similarities. Starting with an unordered and unannotated set of images, the algorithm first extracts the salient details into feature vectors using both color and gradient information. The feature vectors are then used to train a self-organizing map which maps high-dimensional feature vectors onto a 2D canvas so that images with similar feature vectors are grouped together. When users browse the image collection, an image collage is generated that selects and displays the most pertinent set of images based on which portion of the 2D canvas is currently in view. Flowing from an overview to details is a seamless operation controlled simply by pan and zoom, with representative images selected in a consistent and predictable way. To make organizing larger image collections practical in interactive time, the organization algorithm is designed to run in parallel on graphics processing units. Overall this paper presents an end-to-end solution that facilitates the surfing of image collections in a fresh way.  相似文献   
4.
5.
Blue light‐emitting oligotriphenylene nanofibers are synthesized by oxidizing triphenylene using ferric chloride. By adjusting the monomer concentration, the acid used, and the temperature employed, the average diameter and length of the nanofibers can be readily tuned from 50 to 200 nm and 0.5 to 5 μm, respectively. Structural characterization, electrical conductivity, thermal stability, and fluorescence of oligotriphenylene, along with a proposed nanofiber formation mechanism, are presented. Both oligotriphenylene nanofiber dispersions and oligotriphenylene/polysulfone composite films are developed as fluorescent sensors for detecting traces of nitro‐based explosives including nitromethane, nitrobenzene, and 2,4,6‐trinitrophenol, as well as an electron‐deficient metal ion, Fe(III). The sensors exhibit much better selectivity and sensitivity compared to conventional sensors, with detection limits down to 1.0 nm with a detection range covering ~4 orders of magnitude. The detection mechanism of the fluorescent sensors is also disscussed.  相似文献   
6.
Synergy in a neural code   总被引:5,自引:0,他引:5  
We show that the information carried by compound events in neural spike trains-patterns of spikes across time or across a population of cells-can be measured, independent of assumptions about what these patterns might represent. By comparing the information carried by a compound pattern with the information carried independently by its parts, we directly measure the synergy among these parts. We illustrate the use of these methods by applying them to experiments on the motion-sensitive neuron H1 of the fly's visual system, where we confirm that two spikes close together in time carry far more than twice the information carried by a single spike. We analyze the sources of this synergy and provide evidence that pairs of spikes close together in time may be especially important patterns in the code of H1.  相似文献   
7.
A retrospective analysis of 74 cases of transitional cell carcinoma of the renal pelvis and ureter treated at this institution over the past 30 years is presented. When nephrectomy alone or incomplete nephroureterectomy was performed, subsequent transitional cell carcinoma developed in 30% of the ureteral stumps. Subsequent bladder carcinoma occurred in 25% of the patients with primary upper urinary tract carcinoma. The type of initial surgery performed did not appear to influence this incidence of subsequent bladder tumors. Contralateral upper urinary tract carcinoma developed in only one patient. When nephroureterectomy is performed for carcinoma of the renal pelvis and ureter, a cuff of bladder that includes the ureteral orifice should be removed to obviate recurrent disease in the ureteral stump. Since single-incision nephroureterectomy did not include the intramural ureter in 50% of the cases in which it was performed, a second incision may be required for adequate exposure.  相似文献   
8.
The photochromic modification of bianthrone can be produced through a triplet excited state at room temperature in fluid media, as shown by biacetyl photosensitization and phosphorescence quenching. A triplet state of these compounds is observed at 77 K in a methanol ethanol glass, but it is not established if this is the photochromic precursor.  相似文献   
9.
Reliability monitoring is an important part of process control in high-volume production. For metallization, a wafer-level electromigration (WL-EM) test is usually the method of choice to get a good indication of process variation. Different WL-EM methods have been reported, including a constant current method, the SWEAT test, the isothermal test, and the breakdown energy of metal test. The method used in this paper uses the ramping procedure for the isothermal test to achieve the target temperature, but then hold the current constant without feedback correction once the target temperature has been achieved. We present practical normalization procedures to ensure an appropriate wafer-to-wafer comparison that is independent of variation in cross-sectional area as well as of the initial resistance spread. The measurements were performed on a commercially available 200-mm multiside probe station using custom software to implement the current ramp and resistance measurement. Test conditions were achieved through Joule heating; the test structures used were 800-mum-long single lines (no vias) in metal 1 to metal 3, varying in width from 0.14 to 10 mum. Due to variations in the hardware and in the temperature coefficient of resistance (TCR), several normalization steps (described below) were necessary in demonstrating reasonable and expected trends in the data. Results of the analysis suggest that the appropriate value for the current density exponent for this test methodology is two, and they also verify that the TCR varies with linewidth, decreasing as linewidth decreases.  相似文献   
10.
Proposes 3 propositions that may underlie a unificationist view of research in counseling and clinical psychology and discusses contemporary questions concerning research in psychotherapy. The propositions are that (1) psychotherapy research is science, (2) psychotherapy research is part of a unified attempt to understand human behavior, and (3) all scientific tools are acceptable in the effort to understand the process of psychotherapy. These propositions advocate the integration of basic and applied research, theory, and practice and of laboratory-experimental and field-correlational methods. They offer potential answers to questions concerning the practical value of basic research, fact-finding research, laboratory studies, theory, and technological research. The unificationist view suggests that fuller development of the theoretical side of psychological science and the integration of theory with research and application are needed in the scientific study of counseling and psychotherapy. (53 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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