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This study addresses the behaviors of project managers under various conditions of cognitive and affective trust, and the implications for obtaining client loyalty. Theoretical foundations were drawn from interpersonal and interorganizational trust literature. A test of the proposed theoretical framework was conducted in a field setting utilizing a matched design of both project managers and their clients. The results show that reliable project performance positively impacted client loyalty intentions and service‐oriented OCBs positively impacted client secondary retention. An interaction showed that in low cognitive trust situations the project manager behavior of reliable project performance facilitated the obtainment of client loyalty intentions. Implications for research and practice are discussed. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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Food security and food self-sufficiency are important regional goals for the Southern African Development Coordination Conference (SADCC). In the long run, success in these areas would reduce the incidence of drought-related mass starvation and the epidemic of malnutrition and undernutrition that exists among some tribal groups. For food production to improve, the governments must commit themselves to increasing the access of peasant farmers to critical agricultural inputs. If they do not take proper action in this area of development planning, domestic food production is likely to stagnate or decline. This study is a broad examination of the relationship between government expenditures on imported inputs and the performance of the domestic food subsector. Because much data on government spending and agricultural production in Africa are unavailable, and those in published form are of suspect validity, the study is undertaken largely as a conceptual overview. The empirical analyses are conducted, therefore, largely to provide a staging ground for the conceptual arguments.  相似文献   
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Soil treatment of wastewater has the potential to achieve high purification efficiency, yet the understanding and predictability of purification with respect to removal of viruses and other pathogens is limited. Research has been completed to quantify the removal of virus and bacteria through the use of microbial surrogates and conservative tracers during controlled experiments with three-dimensional pilot-scale soil treatment systems in the laboratory and during the testing of full-scale systems under field conditions. The surrogates and tracers employed included two viruses (MS-2 and PRD-1 bacteriophages), one bacterium (ice-nucleating active Pseudomonas), and one conservative tracer (bromide ion). Efforts have also been made to determine the relationship between viruses and fecal coliform bacteria in soil samples below the wastewater infiltrative surface, and the correlation between Escherichia coli concentrations measured in percolating soil solution as compared with those estimated from analyses of soil solids. The results suggest episodic breakthrough of virus and bacteria during soil treatment of wastewater and a 2 to 3 log (99-99.9%) removal of virus and near complete removal of fecal coliform bacteria during unsaturated flow through 60 to 90 cm of sandy medium. Results also suggest that the fate of fecal coliform bacteria may be indicative of that of viruses in soil media near the infiltrative surface receiving wastewater effluent. Concentrations of fecal coliform in percolating soil solution may be conservatively estimated from analysis of extracted soil solids.  相似文献   
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Congenital heart defects (CHDs) are associated with neurodevelopmental (ND) delay. This study aims to assess evidence for impaired prenatal brain development, in fetuses with CHD. A systematical search was performed, and 34 studies evaluating the fetal brain [magnetic resonance imaging (MRI) or ultrasound] in isolated CHD were included (1990–2015). Data regarding cerebral abnormalities, head circumference growth and middle cerebral artery flow were extracted. Prenatal MRI was studied in ten articles (445 fetuses), resulting in a pooled prevalence of 18% (95%CI −6%; 42%) for combined structural and acquired cerebral abnormalities. Prenatal head circumference was studied in 13 articles (753 fetuses), resulting in a pooled z-score of −0.51 (95%CI −0.84; −0.18). Doppler was studied in 21 articles (1412 fetuses), resulting in a lower middle cerebral artery pulsatility index (z-score −0.70 95%CI −0.99; −0.41) in left-sided CHD only. We conclude that prenatal MRI and ultrasound demonstrate brain abnormalities, delay in head growth and brainsparing in subgroups of CHD. However, large MRI studies are scarce, and ultrasound data are biased towards severe and left-sided CHD. Long-term follow-up studies correlating prenatal findings with postnatal ND outcome are limited, and data are lacking to support counseling families regarding ND outcome based on prenatal findings suggestive of altered brain development. © 2016 John Wiley & Sons, Ltd.  相似文献   
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Objectives: Engaging in active transport modes (especially walking) is a healthy and environmentally friendly alternative to driving and may be particularly beneficial for older adults. However, older adults are a vulnerable group: they are at higher risk of injury compared with younger adults, mainly due to frailty and may be at increased risk of collision due to the effects of age on sensory, cognitive, and motor abilities. Moreover, our population is aging, and there is a trend for the current cohort of older adults to maintain mobility later in life compared with previous cohorts. Though these trends have serious implications for transport policy and safety, little is known about the contributing factors and injury outcomes of pedestrian collision. Further, previous research generally considers the older population as a homogeneous group and rarely considers the increased risks associated with continued ageing.

Method: Collision characteristics and injury outcomes for 2 subgroups of older pedestrians (65–74 years and 75+ years) were examined by extracting data from the state police–reported crash dataset and hospital admission/emergency department presentation data over the 10-year period between 2003 and 2012. Variables identified for analysis included pedestrian characteristics (age, gender, activity, etc.), crash location and type, injury characteristics and severity, and duration of hospital stay. A spatial analysis of crash locations was also undertaken to identify collision clusters and the contribution of environmental features on collision and injury risk.

Results: Adults over 65 years were involved in 21% of all pedestrian collisions. A high fatality rate was found among older adults, particularly for those aged 75 years and older: this group had 3.2 deaths per 100,000 population, compared to a rate of 1.3 for 65- to 74-year-olds and 0.7 for adults below 65 years of age. Older pedestrian injuries were most likely to occur while crossing the carriageway; they were also more likely to be injured in parking lots, at driveway intersections, and on sidewalks compared to younger cohorts. Spatial analyses revealed older pedestrian crash clusters on arterial roads in urban shopping precincts. Significantly higher rates of hospital admissions were found for pedestrians over the age of 75 years and for abdominal, head, and neck injuries; conversely, older adults were underrepresented in emergency department presentations (mainly lower and upper extremity injuries), suggesting an increased severity associated with older pedestrian injuries. Average length of hospital stay also increased with increasing age.

Conclusion: This analysis revealed age differences in collision risk and injury outcomes among older adults and that aggregate analysis of older pedestrians can distort the significance of risk factors associated with older pedestrian injuries. These findings have implications that extend to the development of engineering, behavioral, and enforcement countermeasures to address the problems faced by the oldest pedestrians and reduce collision risk and improve injury outcomes.  相似文献   
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In the western United States, livestock grazing often co-exists with recreation, cultural resource management and biodiversity protection on federal and state protected rangelands as well as on many local government open space areas. While the value of livestock grazing for managing rangeland vegetation to reduce fire fuel loads and improve wildlife habitat is increasingly recognized by resource management professionals, public concerns, and conflict between recreationist and livestock have led to reductions in public land grazing. Traditional public input methods yield a constrained picture of people’s attitudes toward cows and public land grazing. Public meetings, hearings, and surveys, the most commonly used mechanisms for public land managers to solicit public opinion, tend to foster participation of organized special interests or, in the case of surveys, focus on a specific topic. General public input is limited. This study explored the use of personal photography in social media to gain insight into public perceptions of livestock grazing in public spaces. Key findings of this study include that many recreationist in grazed San Francisco Bay Area parks shared views, interests, and concerns about cows and grazing on the photo-sharing website, FlickrTM that seldom show up at a public meeting or in surveys. Results suggest that social media analysis can help develop a more nuanced understanding of public viewpoints useful in making decisions and creating outreach and education programs for public grazing lands. This study demonstrates that using such media can be useful in gaining an understanding of public concerns about natural resource management.  相似文献   
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