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51.
This paper develops a framework for understanding the interaction between person-centered leadership by project managers (a.k.a. vertical leadership (VLS)) and team-centered leadership by individuals in the project team (a.k.a. horizontal leadership (HSL)). It builds on Archer's Realist Social Theory and its morphogenetic cycle, which describes the interaction of structure with agency for task fulfillment and the resulting reshaping (morphogenesis) or continuation (morphostasis) of structure for subsequent iterations of the cycle. Data were collected globally in 33 case studies with 166 interviews and analyzed using Alvesson's Constructing Mystery technique. A theory about the cycles and events that shape the interaction between VLS and HLS is developed, which includes events such as nomination, identification, selection, execution and governance, as well as transitioning. Managerial and theoretical implications are discussed.  相似文献   
52.
DESIGN: Case-control study among incident African patients with cancer. Questionnaire assessment of exposure to tobacco, occupation, and place of birth. SETTING: Northern Province, South Africa. SUBJECTS: Between 1993 and 1995, 288 men and 60 women with lung cancer and 183 male and 197 female controls (consisting of patients newly diagnosed with cancers other than those known to be associated with smoking) were interviewed. Unmatched, unconditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs) of developing lung cancer in relation to a number of variables. MAIN OUTCOME MEASURE: Risk of developing lung cancer related to exposure to tobacco, indoor pollution, dusty work environment, and residential exposure to asbestos. RESULTS: There was a significant increase in the risk of developing lung cancer through smoking. In men, the ORs were 2.2 (95% CI = 1.0 to 4. 6) in ex-smokers, 9.8 (95% CI = 5.9 to 16.4) in light smokers (0-14 g/day), and 12.0 (95% CI = 6.5 to 22.3) in heavy smokers. In women, the ORs were 5.8 (95% CI = 1.3 to 25.8) in ex-smokers and 5.5 (95% CI = 2.6 to 11.3) in current smokers. Work in a dusty industry showed an elevated risk (OR = 3.2, 95% CI = 1.8 to 5.8) for lung cancer only in men. Male residents of areas where asbestos was shipped for distribution (termed moderately polluted asbestos areas) had a 2.5-fold increase (95% CI = 1.0 to 4.4) in the risk (OR) of developing lung cancer, and residents of areas where asbestos was mined (termed heavily polluted asbestos areas) had a 2.8-fold increase in risk (95% CI = 0.7 to 10.4). Female residents of heavily polluted asbestos areas showed elevated risks of 5.4 (95% CI = 1.3 to 22.5) of developing lung cancer. CONCLUSION: The data suggest that tobacco smoking is the most important risk factor for the development of lung cancer in this setting. Risks for lung cancer are reminiscent of those observed in Western countries in the 1960s and 1970s. However, environmental exposure to asbestos, a dusty occupation (in men), and perhaps indoor air pollution may also contribute to the development of lung cancer in this province.  相似文献   
53.
Products can support user groups in social interaction and/or physical play in various ways. Depending on the requirements and needs of specific user groups and contexts of use, different approaches are applied to create successful designs. This special issue contains papers that describe designs for children, adults and elderly for sports, home and outdoor contexts. The papers in this issue explore how technology can contribute to enhancing user experiences in terms of social interaction and physical activities. Knowledge from very diverse research areas, such as, social psychology, persuasive technology, child development, human–robot interaction, and creativity is used as an inspiration source for the various projects.  相似文献   
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We report the synthesis, radiosynthesis and biological characterisation of two gonadotropin-releasing hormone receptor (GnRH−R) antagonists with nanomolar binding affinity. A small library of GnRH−R antagonists was synthesised in 20–67 % overall yield with the aim of identifying a high-affinity antagonist capable of crossing the blood–brain barrier. Binding affinity to rat GnRH−R was determined by autoradiography in competitive-binding studies against [125I]buserelin, and inhibition constants were calculated by using the Cheng–Prusoff equation. The radioligands were obtained in 46–79 % radiochemical yield and >95 % purity and with a molar activity of 19–38 MBq/nmol by direct nucleophilic radiofluorination. Positron emission tomography imaging in rat under baseline conditions in comparison to pretreatment with a receptor-saturating dose of GnRH antagonist revealed saturable uptake (0.1 %ID/mL) into the brain.  相似文献   
56.
A new automated static optical image analysis (SOIA) method was developed for characterising the shape of sodium oxalate crystals by separately measuring their length and width. The automated size analysis combines crystal image acquisitioning with a custom-developed numerical algorithm for morphological analysis of crystals. The automation of the two main measuring steps enables characterisation of a large number of crystals ensuring statistically meaningful results. As part of the numerical algorithm, a rectangularity-based morphological filter was implemented to eliminate overlapping crystals and crystal networks. The developed optical sizing technique has a low detection limit of 0.25 μm, which is close to the theoretical resolution of optical microscopy. It is demonstrated that the new automated SOIA sizing technique is very sensitive in identifying oxalate crystals of different shape. The measured crystal size distributions are compared to those obtained by an AccuSizer sizing instrument to confirm that they are consistent with the measurements obtained by a conventional crystal sizing instrument.  相似文献   
57.
Bekker  Jessa  Davis  Jesse 《Machine Learning》2020,109(4):719-760

Learning from positive and unlabeled data or PU learning is the setting where a learner only has access to positive examples and unlabeled data. The assumption is that the unlabeled data can contain both positive and negative examples. This setting has attracted increasing interest within the machine learning literature as this type of data naturally arises in applications such as medical diagnosis and knowledge base completion. This article provides a survey of the current state of the art in PU learning. It proposes seven key research questions that commonly arise in this field and provides a broad overview of how the field has tried to address them.

  相似文献   
58.
This paper describes three design values that we apply for designing playful interactions. Interactive play objects can stimulate social interaction and physical play by providing motivating feedback to players’ behavior; they can allow players to create their own game goals and rules in an open-ended play context and support social player interaction patterns. This design approach is illustrated by six design cases in which our assumptions were examined in various play contexts. The results show that the application of these design values can lead to rich and appealing innovative play concepts. Players can create a wide range of (physical) games using open-ended play objects, and properties of the play objects, such as being personal or shared, influence the type of social interaction.  相似文献   
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Thirteen patients with severe Paget's disease of bone [mean serum alkaline phosphatase (SAP) level 17 times the upper limit of normal] were treated with 30 mg oral risedronate daily for 8 weeks. Patients were followed for 16 weeks without treatment. The change from baseline SAP was the primary end point. Those patients whose SAP levels did not reach the normal range were retreated with 30 mg for another 8 weeks. There was a mean percent decrease in SAP of 77% after the first course of risedronate treatment and 87% after the second course of treatment. All patients who completed the study had a decrease in SAP of at least 77% from the baseline. The urinary hydroxyproline/creatinine level was decreased by 64% and 79%, respectively, during the first and second treatment courses. There were transient asymptomatic decreases in serum calcium and phosphorus levels. The urinary calcium/creatinine ratio also decreased in these patients. Serum intact PTH and 1,25-dihydroxyvitamin D levels increased transiently during risedronate treatment. Oral risedronate was well tolerated by the patients. Only one patient discontinued treatment because of an adverse event (diarrhea) thought to be related to risedronate therapy.  相似文献   
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