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11.
Longitudinal analyses on normal versus impaired functioning across 7 domains were conducted in children who had experienced profound institutional deprivation up to the age of 42 months and were adopted from Romania into U.K. families. Comparisons were made with noninstitutionalized children adopted from Romania and with nondeprived within-U.K. adoptees placed before the age of 6 months. Specifically, the validity of the assessment, the degree of continuity and change in levels of functioning from 6 to 11 years, and the factors in the pre- and postadoption environment accounting for heterogeneity in outcome were examined. Pervasive impairment was significantly raised in children experiencing institutional deprivation for ≥6 months of life, with a minority within this group showing no impairment. There was no additional significant effect of duration of deprivation beyond the 6-month cutoff, and few other predictors explained outcome. The pattern of normality/impairment was mainly established by 6 years of age, with considerable continuity at the individual level between 6 and 11 years. The findings are discussed in terms of the possibility of a sensitive period for development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
12.
Many companies and purchasing departments only possess a limited knowledge about the modelling of inter-company business processes for electronic procurement. In the past the discussion about electronic procurement was mostly focused on technical aspects. This article introduces a reference process model for procurement auctions. The process model is made up of a basic process, which describes a minimal process for procurement auctions, and a number of process alternatives, which allow for the adoption of the basic process to changing parameters and individual company requirements.  相似文献   
13.
Quantitative RT-PCR for measuring gene expression   总被引:1,自引:0,他引:1  
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15.
This paper presents work directed at capturing the entrepreneurial and collaborative activity of university researchers. The Triple Helix points to the emergence of the entrepreneurial university as well as to an increasing overlay of activities in universities, industry and government. This study explores ways in which patent-based metrics could be utilized in a Triple Helix context, and how hybrid indicators could be developed by combining patent with survey data. More specifically, it aims to develop indicators that connect technological inventiveness of university researchers to both funding organizations and users, as well as to entrepreneurial activities by academics. The paper develops a simplified model of the innovation process to benchmark the relevance of the indicators to the Triple Helix. An analysis of Finnish academic patents illustrates that patent data can already provide useful indicators but, on its own, cannot provide information about how academic patents are interconnected with government or industry through funding or utilization links. An exclusive analysis of patents can point to patent concentrations on certain universities, to inventors and assignees, or to potential gaps in translating applied science into industrial technology. However, the patent data had to be combined with an inventor survey in order to relate academic patents more to their Triple Helix environment. The survey indicated that most patented academic inventions are connected to (often publicly funded) scientific research by the inventors and tend to be utilized in large firms rather than in start-up companies founded by academic entrepreneurs.  相似文献   
16.
If a low weight percentage of crude fine fillers can improve properties of polymer materials directly without complicated chemical treatment process involved, it will be significant for many industrial applications. Our previous study indicated that a kind of Cancun natural sand could be an effective filler material for polymer composites. In this current work, the epoxy composites reinforced by this kind of natural sand particles were prepared and thermal and mechanical properties of the composites containing up to 5 wt % of the sand particles were characterized. Results showed that the highest flexural strength appears in the epoxy composite containing 1 wt % sand particles. A damage model was used to interpret the flexural properties, which showed an acceptable agreement with the experimental results. The glass transition temperature, high temperature storage modulus, and dimensional stability of the sand/epoxy composites monotonically increased with the addition of the sand particles. The sand particle/epoxy composites also displayed a noticeable enhancement in thermal conductivity. Theoretical analysis showed that in addition to conduction, other heat transport mechanisms played roles in the improved heat transmission through the composites. As a natural porous micron-scale material, Cancun sand has the potential for applications in cost-effective composites with enhanced mechanical and thermal properties. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
17.
The electrical resistivity of short carbon fibre filled thermoplastic elastomers based on natural rubber-high density polyethylene (NR-HDPE) blend and styrene-isoprene-styrene (S-I-S) block copolymer has been studied by varying the concentration of fibre from the 0 to 40 phr level. A sharp drop in resistivity is observed in both cases after a critical concentration of fibre is reached, with the S-I-S system showing lower values of critical concentration. At higher concentrations, experimental values of the electrical conductivity agreed reasonably well with the calculated values from a theory based on the probability of formation of a conductive network. The effect of temperature on the resistivity of the composites has also been investigated in a temperature range of 27–120 °C and 27–90 °C for the NR-HDPE system and S-I-S system, respectively. The type of carrier in both the composites is found to be n-type, i.e. electrons, and the activation energy of hopping of the electrons for both the systems has been calculated. A Hall effect study has also been carried out to determine the carrier concentration and drift mobility of both the composites.  相似文献   
18.
Wide band gap a-SiOx:H films have been prepared by the photochemical decomposition of a SiH4, CO2 and H2 gas mixture. Deposition parameters namely the CO2 to SiH4 gas flow ratio, H2 dilution and chamber pressure were optimized in order to achieve highly photoconducting (1 × 10-6 S cm-1) films with an optical gap of 1.99 eV. The optical gap was found to increase with an increase in the CO2 to SiH4 flow ratio. A decrease in the photoconductivity, refractive index, spin g-value and a simultaneous increase in the spin density are attributed to an incorporation of oxygen into the films. Upon hydrogen dilution the photoconductivity of a-SiOx:H films was observed to improve along with an increase of the optical gap. The spin density of a-SiOx:H films was of the order of 1017 cm-9. The optoelectronic properties of the films have been correlated with the bonding configurations in the film, deposition parameters and the growth kinetics. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
19.
Although filial therapy has traditionally been viewed as suitable for children of diverse cultures, there is limited research to support this perspective. This qualitative case study examined the perceived effectiveness of filial therapy for a Jamaican mother and the perceived effect on the mother-child relationship. Findings indicate that some aspects of filial therapy are congruent with the parenting practices and values of this Jamaican mother. The mother reported an increase in empathy, a heightened awareness of her child's needs, and a stronger relationship with her child. She expressed some difficulty with limit setting and tracking skills taught as part of the model. Future research directions include further examination of the compatibility of filial therapy with other Jamaican parents and the effectiveness of group filial therapy with Jamaican parents or other parents of Caribbean descent. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
20.
Nutrient export from agricultural land to surface waters is a significant environmental concern within the Great Lakes Basin (GLB). A field-based watershed-scale study was completed to investigate spatial and temporal variations of phosphorus and nitrate to assess nutrient transport pathways and groundwater-surface water interactions in an agriculturally dominated clay plain system. This was conducted in the 127 km2 Upper Parkhill Watershed, near Lake Huron in southwestern Ontario, Canada. Data collection occurred from June 2018 to May 2019 via continuous sensor deployment and discrete sampling of stream water, groundwater, hyporheic zone, and tile drainage water. Samples were analyzed for various nutrient species (total, total dissolved, soluble reactive, and particulate phosphorus, and nitrate-N) to examine the hydrological dynamics of principal transport pathways of agriculturally-derived nutrients. Total phosphorus and nitrate concentrations in stream water ranged from 0.007 to 0.324 mg/L and 0.32 to 13.13 mg NO3?-N/L, respectively. Tile drainage water total phosphorous concentrations varied from 0.006 to 0.066 mg/L. Groundwater total dissolved phosphorus concentrations ranged from <0.003 to 0.085 mg/L. Transport of phosphorus through tile drainage was observed to be greater than through groundwater over the study period. No distinct relationship was observed between nutrient concentrations in the hyporheic zone and the vertical hydraulic gradient within this zone in the studied stream reach. Preliminary correlations were discerned between water quality observations and recognized land management practices. Given the elevated stream nutrient concentrations, these results are consequential for the continual improvement of strategies and programs devised to conserve water resources within the GLB.  相似文献   
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