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201.
The construction industry is heavily dependent on the adequate supply of a skilled labour force, and as a result the skilled labour shortage in the UK has received considerable attention in recent years. With the current economic recovery the industry is expected to experience considerable skills shortages in both traditional and new skills areas. This paper analyses the views of construction employers in relation to the response strategies promoted by industry and government and identified in previous research which tackle elements of the skills shortage problem within the UK construction industry. The paper describes seven existing industry and government schemes, and a further nine alternative response strategies to the construction skills shortage. The survey analysis demonstrates that construction employers support: (i) the Construction Skills Certification Scheme, (ii) the Investors in People standard, (iii) economic stability within the industry; (iv) long term industry-wide training plans, (v) a return to direct employment; and (vi) the development of new technologies and construction techniques. It is concluded that the effectiveness of alternative response strategies is linked to the traditional approach of most contractors. 相似文献
202.
Lothar Sims Ulrich Hörmann Robert Hanfland Roderick C.I. MacKenzie F. René Kogler Roland Steim Wolfgang Brütting Pavel Schilinsky 《Organic Electronics》2014,15(11):2862-2867
A common failure mechanism of organic solar cells is the development of an s-shaped current voltage curve. Herein, we investigated the origin of this degradation mechanism by replacing the commonly used hole selective layer poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) with a co-evaporated layer of N,N′-bis(3-methylphenyl)-N,N′-bis(phenyl)benzidine (TPD) and Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (HATCN). By varying the ratio of TPD to HATCN we are able to tune both the mobility and work function of the hole selective layer. Using a combination of field effect mobility measurements, Kelvin-Probe work function measurements, and numerical modeling we demonstrate that a degraded mobility of the hole selective layer leads to a buildup of charge within the device and reduction of fill factor. 相似文献
203.
The ability to predict the effects of point mutations on the interaction of alpha-helices within membranes would represent a significant step toward understanding the folding and stability of membrane proteins. We use structure-based empirical parameters representing steric clashes, favorable van der Waals interactions, and restrictions of side-chain rotamer freedom to explain the relative dimerization propensities of 105 hydrophobic single-point mutants of the glycophorin A (GpA) transmembrane domain. Although the structure at the dimer interface is critical to our model, changes in side-chain hydrophobicity are uncorrelated with dimer stability, indicating that the hydrophobic effect does not influence transmembrane helix-helix association. Our model provides insights into the compensatory effects of multiple mutations and shows that helix-helix interactions dominate the formation of specific structures. 相似文献
204.
The empirical literature supports the idea of groups developing structure over time in a predictable sequence. This is a clinically useful way of conceptualizing the whole group, especially closed time-limited groups. Two general types of development are discussed: one based on recurrent cyclical patterns and the other on progressive linear patterns. A basic 4-stage model is described consisting of 4 sequential stages: engagement, differentiation, interpersonal work, and termination. This model is compatible with findings from both cyclic and linear aspects of the literature. Clinical application is discussed with a particular focus on structural aspects of group organization and specific technical intervention strategies. These strategies are particularly useful when considering how to implement a variety of models of group psychotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
205.
A volume-preserving three-dimensional smoothing approach is described that can be directly applied to 3D medical image data consisting of sets of 2D image slices, e.g., segmented intravascular ultrasound image sequences. Two local smoothing filters ℱ and 𝒢 were designed according to different smoothing goals and their performance was compared. Filtering with the ℱ filter of a relatively large frequency window keeps the important local characteristics of the object and results in little shrinkage while removing noise. Filtering with the Gaussian filter G that has an added volume compensation step results in no global shrinkage and may be used for multiscale filtering. The two filters can be easily extended to n-dimensional filtering. 相似文献
206.
207.
AT Saadi CC Blackwell SD Essery MW Raza OR el Ahmer DA MacKenzie VS James DM Weir MM Ogilvie RA Elton A Busuttil JW Keeling 《Canadian Metallurgical Quarterly》1996,16(1):51-59
The pharmacokinetic properties of glucagon-like peptide-1(7-36)amide (GLP-1(7-37) were compared. Four beagle dogs received on 4 separate occasions s.c. bolus doses of 50 micrograms/kg, and 2 min i.v. infusions of 50 micrograms/kg of each peptide. The plasma immunoreactivity of GLP-1 (P-GLP-1-IR) was measured by a sandwich enzyme-linked immunosorbent assay (ELISA). After i.v. infusion, the plasma half-life in the first-phase was 2.1 +/- 0.1 and 2.4 +/- 0.3 min, in the final-phase 68 +/- 6 and 81 +/- 3 min, the total plasma clearance 25 +/- 3 and 22 +/- 4 ml/kg.min, the volume of distribution at steady state 0.16 +/- 0.02 and 0.84 +/- 0.24 l/kg, and the mean residence time 6.2 +/- 0.3 and 36 +/- 5 min for GLP-1(7-36)amide and GLP-1(7-37), respectively. After s.c. administration, the maximum plasma concentration was reached after 15 +/- 5 and 19 +/- 4 min and the absolute bioavailability was 48 +/- 7 and 49 +/- 13% for GLP-1(7-36)amide and GLP-1(7-37), respectively. P-GLP-1-IR, measured by a radioimmunoassay (RIA), was considerably higher than when measured by ELISA. This discrepancy was due to cross-reactivity with metabolites of the parent peptide. The plasma degradation was studied in vitro in dog plasma at 37 degrees C, and the half-lives were found to be 61 +/- 9 and 132 +/- 16 min for GLP-1(7-36)amide and GLP-1(7-37), respectively (n = 6). Bacitracin inhibited the degradation of both peptides. 相似文献
208.
DJ Wustrow T Capiris R Rubin JA Knobelsdorf H Akunne MD Davis R MacKenzie TA Pugsley KT Zoski TG Heffner LD Wise 《Canadian Metallurgical Quarterly》1998,8(16):2067-2070
A series of 3-phenylpyrazolo[1,5-a]pyrimidines was prepared and found to have affinity for the human CRF-1 receptor. The 3-dimensional structure of one of the most potent analogs in this series, 10d, was determined by X-ray crystallography and suggests the spatial requirements for potent CRF-1 receptor binding affinity in this series. 相似文献
209.
J MacKenzie J Sheldon G Morgan G Cook TF Schulz RF Jarrett 《Canadian Metallurgical Quarterly》1997,350(9085):1144-1145
210.
EJ MacKenzie JA Morris GJ Jurkovich Y Yasui BM Cushing AR Burgess BJ DeLateur MP McAndrew MF Swiontkowski 《Canadian Metallurgical Quarterly》1998,88(11):1630-1637
OBJECTIVES: This study examined factors influencing return to work (RTW) following severe fracture to a lower extremity. METHODS: This prospective cohort study followed 312 individuals treated for a lower extremity fracture at 3 level-1 trauma centers. Kaplan-Meier estimates of the proportion of RTW were computed, and a Cox proportional hazards model was used to examine the contribution of multiple risk factors on RTW. RESULTS: Cumulative proportions of RTW at 3, 6, 9, and 12 months post-injury were 0.26, 0.49, 0.60, and 0.72. After accounting for the extent of impairment, characteristics of the patient that correlated with higher rates of RTW included younger age, higher education, higher income, the presence of strong social support, and employment in a white-collar job that was not physically demanding. Receipt of disability compensation had a strong negative effect on RTW. CONCLUSIONS: Despite relatively high rates of recovery, one quarter of persons with lower extremity fractures did not return to work by the end of 1 year. The analysis points to subgroups of individuals who are at high risk of delayed RTW, with implications for interventions at the patient, employer, and policy levels. 相似文献