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81.
Doris Kemp 《Rocks & Minerals》2013,88(12):765-766
  相似文献   
82.
A project to assess the impact on the transmission and distribution (TD) system due to the implementation of demand-side management (DSM) programs is described. Traditional TD planning methods are reviewed and procedural changes necessary to fully integrate DSM strategy analysis with the system planning process are discussed. Test procedures and results are discussed for a study conducted at a host utility. Several DSM strategies are analyzed to assess the impacts on a TD system serving a large metropolitan area  相似文献   
83.
Developed an additive model to account for reading times for 2 different reading tasks (reading for retention and reading for comprehension). The reading strategies of 48 college students and 64 5th graders and individual differences between fast and slow readers were examined. Ss were assumed to have processors that handle the lexical, structural, and meaning information in sentences. The various task, age, and reading speed groups were hypothesized to use the 3 processors for differing amounts of time. The model was supported by word-by-word reading times for 80 sentences and by 9 empirical indices of lexical, structural, and meaning attributes of text. Results show that for skilled adult Ss, relatively more time was spent processing structure in the retention task, and meaning in the comprehension task. Fifth graders had not fully mastered the connection between task demands and linguistic processors shown by adults, and thus used mixtures of the adult strategies. (101 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
As a number of seasonal factors affect cutaneous synthesis of vitamin D, especially in young children, our objective was to verify if winter and summer vitamin D intakes in Quebec preschoolers reach the adequate intake of 5 microg/day. A three-month retrospective food frequency questionnaire and a 24-hour food recall were used with parents of 98 children (mean age 56 months) in summer and of 72 of these children (mean age 65 months) in winter. To ensure completeness of data, vitamin D content of foods not covered in the Canadian Nutrient File was taken from other sources. According to the food frequency questionnaire, total vitamin D intakes were 9.7 +/- 4.3 microg/day in summer and 11.6 +/- 4.8 microg/day in winter. Only 10% of children in summer and 7% in winter had an intake below 5 microg/day. The 24-hour food recall vitamin D intake estimate was lower (summer 7.0 +/- 3.8 microg/day, winter 7.2 +/- 4.2 microg/day). This difference could be partly due to a discrepancy in the estimation of multivitamin supplement intake. However, according to both estimates, vitamin D intakes appeared generally adequate in this sample of Quebec preschoolers.  相似文献   
85.
Examination of the range and limits of cognitive developmental reserve capacity (plasticity) by means of cognitive training has been proffered as a promising diagnostic strategy for the early identification of Alzheimer's disease. Previous findings of differential gains after cognitive training for healthy older persons and older persons at risk for dementia were supported, rendering cognitive plasticity a criterion by which the overlap in performance distributions between healthy older persons and older persons at risk can be reduced. Stepwise hierarchical regression analyses demonstrated that posttraining scores, which represented developmental reserve capacity, explained significantly more variance in mental health status than pretest or baseline performance. Older persons at risk profited significantly less from training in 2 components of fluid intelligence, figural relations, and inductive reasoning. The authors discuss the possibilities of turning this testing-the-limits procedure into an instrument for screening purposes in clinical practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
86.
The problem of parameter estimation of superimposed signals in white Gaussian noise is considered. The effect of the correlation structure of the signals on the Cramer-Rao bounds is studied for both the single and multiple experiment cases. The best and worst conditions are found using various criteria. The results are applied to the example of parameter estimation of superimposed sinusoids, or plane-wave direction finding in white Gaussian noise, and best and worst conditions on the correlation structure and relative phase of the sinusoids are found. This provides useful information on the limits of the resolvability of sinusoid signals in time series analysis or of plane waves in array processing. The conditions are also useful for designing worst-case simulation studies of estimation algorithms, and for the design of minimax signal acquisition and estimation procedures, as demonstrated by an example  相似文献   
87.
This work is aimed to conclude the effect of section thickness of a high pressure die cast (hpdc) Mg alloy on the tensile properties as ambiguous conclusions are presented in the literature. Tensile tests were performed on as-cast hpdc AZ91 alloy and the effect of section thickness on the tensile properties such as yield strength (YS), ultimate tensile strength (UTS), ductility and fracture strain (FS) are explained. Additionally, explanation on the microfailure mode of the material is presented to explain the influence of different microfeatures on the failure process. The average size, area fraction and clustering tendency of pores and Mg17Al12 (β) particles as well as average grain size are quantified and their effects on section thickness are obtained. The results confirm that the UTS, YS, ductility and FS are mainly influenced by the area fraction, size distribution and spatial arrangement of pores and phases.  相似文献   
88.
Proposes a model to explain the transitions experienced by training directors during an internship year. Six transitions are identified, including courting, bonding, rapprochement, mentoring, launching, and reunion, and the particular behaviors and events that signal each passage are described. These transitions are contrasted with those often experienced by interns. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
A general numerical solver for analyzing microstrip geometries of rectangular shape is presented in this paper. The analytical foundation of this solver is based on an integral equation approach which we formulate in the spatial domain. The unknown surface current on the microstrip is solved by the method of moments using 2D rectangular pulses as the expansion functions. Transmission-line modeling is then used to parameterize a given microstrip junction or discontinuity. Aided by a graphics interface, this solver can analyze complex structures without incurring additional analytical complexity. We illustrate the accuracy and versatility of our solver by applying it to several different microstrip discontinuities ranging from a single-stub to an interdigitated capacitor.  相似文献   
90.
Ovarian granulosa cell tumors (GCTs) are thought to arise from cells of the ovarian follicle and comprise a rare entity of ovarian masses. We recently identified the G-protein-coupled estrogen receptor (GPER/GPR30) to be present in granulosa cells, to be regulated by gonadotropins in epithelial ovarian cancer and to be differentially expressed throughout folliculogenesis. Thus, supposing a possible role of GPER in GCTs, this study aimed to analyze GPER in GCTs. GPER immunoreactivity in GCTs (n = 26; n (primary diagnosis) = 15, n (recurrence) = 11) was studied and correlated with the main clinicopathological variables. Positive GPER staining was identified in 53.8% (14/26) of GCTs and there was no significant relation of GPER with tumor size or lymph node status. Those cases presenting with strong GPER intensity at primary diagnosis showed a significant reduced overall survival (p = 0.002). Due to the fact that GPER is regulated by estrogens, as well as gonadotropins, GPER may also be affected by endocrine therapies applied to GCT patients. Moreover, with our data supposing GPER to be associated with GCT prognosis, GPER might be considered as a possible confounder when assessing the efficacy of hormone-based therapeutic approaches in GCTs.  相似文献   
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