1,343 research outputs found

    Instrumentality of Aggression and Strength and Arbitrariness of Frustration Related to Direct Physical Aggression

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    Study of the factors influencing the occurrence of aggression received impetus from the frustration-aggression hypothesis of 1939. It was hypothesized that aggression was the primary consequence of frustration, and that the stronger the frustration, the stronger the aggression. Numerous studies have shown that frustration can lead to aggression v/ith organisms ranging along the phylogenetic scale from rats to humans. While questionnaire studies have shown that the strength of aggression varies v/ith the strength of frustration, this has not been verified in laboratory studies of direct physical aggression. Recently, the importance of situational variables, such as the perceived arbitrariness of the frustration, have been stressed. The influence of this variable also has not been verified in laboratory study of direct physical aggression. V/hat happens after an aggressive act, influences the probability of future aggression. The instrumentality of aggression refers to the effectiveness of aggression in overcoming an obstacle to a goal. Instrumentality has been studied in the laboratory but not in the most effective manner. Instrumentality of aggression and the strength and arbitrariness of frustration, in relation to direct physical aggression, were investigated by employing the aggression machine (Buss, 1961) in an ostensible learning task. The subjects, 120 male Introductory Psychology students, were required to teach a confederate a concept. Frustration consisted in the confederate\u27s inability to learn the concept. The measure of aggression was the mean intensity of shock ostensibly administered to the confederate for incorrect responses. Different strengths of frustration were established by blocking at a point near the completion of the learning task and at another point more distant. There was a control group which was to experience no frustration. Instrumentality was established by reinforcement of high intensity shocks in the warmup task for those subjects in the instrumental condition but not for those in the noninstrumental condition. Arbitrariness was established through the instructions, which attempted to have the frustration viewed as arbitrary or nonarbitrary. It was hypothesized that: the strength of aggression would increase with the strength of frustration; more aggression would occur under the arbitrary than under the nonarbitrary condition; more aggression would occur when aggression was instrumental than when it was noninstrumental; and the most aggression would occur when aggression was instrumental and frustration was strong and arbitrary. The results of this study show that it was possible to establish different strengths of frustration on the basis of blocking near to or far from a goal. The stronger frustration produced more aggression than the v/eaker frustration but only when aggression was experienced as instrumental in overcoming frustration. Additional support for the frustration-aggression hypothesis was provided by ,the increase in aggression as the number of frustrations increased. No more aggression occurred in the condition where frustration was intended to be viewed as arbitrary than in the condition where frustration was intended to be viewed as nonarbitrary. This was not interpreted as indicating that situational aggression eliciting stimuli, the arbitrariness of frustration in particular, are not important determinants of aggression. Rather, the wording of the instructions was viewed as a possible cause for the ineffectiveness of this variable. The control group proved to be ineffective in this study. It was hypothesized that rather than being a control group, that this group, because of the schedule of the victim\u27s responses, really was an additional frustration group. The results of the experiment were seen as providing some support for this hypothesis

    Unifying Services Marketing and Operations with Service Experience Management

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    One of the pioneer firms in the leisure cruise industry embarked on a bold idea in 2000 to offer an unregimented experience unlike most cruises. Despite the appeal of the concept from a marketing perspective, the service innovation posed operational challenges, many of which continue to undermine the firm’s competitive position. Using a multi-method empirical approach and interdisciplinary views that draw on research from marketing and operations management, the authors analyze this business case to identify challenges that service firms face when services are developed and managed from siloed functional perspectives. Based on their research findings and guided by the literature, the authors derive a service-systems model to aid service planning and management. The authors further highlight a new organizational form and function for services under the domain of service experience management that is positioned as a means to unify service operations and marketing for delivering on service promises. The authors offer direction for further research on service operations systems and service experience management

    Spaceflight Payload Design, Flight Experience G-408

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    Worcester Polytechnic Institute\u27s first payload of spaceflight experiments flew aboard Columbia, STS-40, during June of 1991 and culminated eight years of work by students and faculty. The Get Away Special (GAS) payload was installed on the GAS bridge assembly at the aft end of the cargo bay behind the Spacelab Life Sciences (SLS-l) laboratory. The experiments were turned on by astronaut signal after reaching orbit and then functioned for 72 hours. Environmental and experimental measurements were recorded on three cassette tapes which, together with zeolite crystals grown on orbit, formed the basis of subsequent analyses. The experiments were developed over a number of years by undergraduate students meeting their project requirements for graduation. The experiments included zeolite crystal growth, fluid behavior, and microgravity acceleration measurement in addition to environmental data acquisition. Preparation also included structural design, thermal design, payload integration, and experiment control. All of the experiments functioned on orbit and the payload system performed within design estimates

    Book Reviews

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    Elective Open Suprarenal Aneurysm Repair in England from 2000 to 2010 an Observational Study of Hospital Episode Statistics

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    Background: Open surgery is widely used as a benchmark for the results of fenestrated endovascular repair of complex abdominal aortic aneurysms (AAA). However, the existing evidence stems from single-centre experiences, and may not be reproducible in wider practice. National outcomes provide valuable information regarding the safety of suprarenal aneurysm repair. Methods: Demographic and clinical data were extracted from English Hospital Episodes Statistics for patients undergoing elective suprarenal aneurysm repair from 1 April 2000 to 31 March 2010. Thirty-day mortality and five-year survival were analysed by logistic regression and Cox proportional hazards modeling. Results: 793 patients underwent surgery with 14% overall 30-day mortality, which did not improve over the study period. Independent predictors of 30-day mortality included age, renal disease and previous myocardial infarction. 5-year survival was independently reduced by age, renal disease, liver disease, chronic pulmonary disease, and known metastatic solid tumour. There was significant regional variation in both 30-day mortality and 5-year survival after risk-adjustment. Regional differences in outcome were eliminated in a sensitivity analysis for perioperative outcome, conducted by restricting analysis to survivors of the first 30 days after surgery. Conclusions: Elective suprarenal aneurysm repair was associated with considerable mortality and significant regional variation across England. These data provide a benchmark to assess the efficacy of complex endovascular repair of supra-renal aneurysms, though cautious interpretation is required due to the lack of information regarding aneurysm morphology. More detailed study is required, ideally through the mandatory submission of data to a national registry of suprarenal aneurysm repair

    Comet nucleus and asteroid sample return missions

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    During the 1991-92 academic year, the Pennsylvania State University has developed three sample return missions: one to the nucleus of comet Wild 2, one to the asteroid Eros, and one to three asteroids located in the Main Belt. The primary objective of the comet nucleus sample return mission is to rendezvous with a short period comet and acquire a 10 kg sample for return to Earth. Upon rendezvous with the comet, a tethered coring and sampler drill will contact the surface and extract a two-meter core sample from the target site. Before the spacecraft returns to Earth, a monitoring penetrator containing scientific instruments will be deployed for gathering long-term data about the comet. A single asteroid sample return mission to the asteroid 433 Eros (chosen for proximity and launch opportunities) will extract a sample from the asteroid surface for return to Earth. To limit overall mission cost, most of the mission design uses current technologies, except the sampler drill design. The multiple asteroid sample return mission could best be characterized through its use of future technology including an optical communications system, a nuclear power reactor, and a low-thrust propulsion system. A low-thrust trajectory optimization code (QuickTop 2) obtained from the NASA LeRC helped in planning the size of major subsystem components, as well as the trajectory between targets

    Homologous and heterologous desensitization of guanylyl cyclase-B signaling in GH3 somatolactotropes

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    The guanylyl cyclases, GC-A and GC-B, are selective receptors for atrial and C-type natriuretic peptides (ANP and CNP, respectively). In the anterior pituitary, CNP and GC-B are major regulators of cGMP production in gonadotropes and yet mouse models of disrupted CNP and GC-B indicate a potential role in growth hormone secretion. In the current study, we investigate the molecular and pharmacological properties of the CNP/GC-B system in somatotrope lineage cells. Primary rat pituitary and GH3 somatolactotropes expressed functional GC-A and GC-B receptors that had similar EC50 properties in terms of cGMP production. Interestingly, GC-B signaling underwent rapid homologous desensitization in a protein phosphatase 2A (PP2A)-dependent manner. Chronic exposure to either CNP or ANP caused a significant down-regulation of both GC-A- and GC-B-dependent cGMP accumulation in a ligand-specific manner. However, this down-regulation was not accompanied by alterations in the sub-cellular localization of these receptors. Heterologous desensitization of GC-B signaling occurred in GH3 cells following exposure to either sphingosine-1-phosphate or thyrotrophin-releasing hormone (TRH). This heterologous desensitization was protein kinase C (PKC)-dependent, as pre-treatment with GF109203X prevented the effect of TRH on CNP/GC-B signaling. Collectively, these data indicate common and distinct properties of particulate guanylyl cyclase receptors in somatotropes and reveal that independent mechanisms of homologous and heterologous desensitization occur involving either PP2A or PKC. Guanylyl cyclase receptors thus represent potential novel therapeutic targets for treating growth-hormone-associated disorders

    Weather and our food supply

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    The steep rate of increase in yield of grain crops in the United States since the mid-1950\u27s has resulted in the use of the term explosion in technology. Surplus grains piled up to such proportions after the 1960 · harvest that acreage control appeared. to be in order. But despite substantial reductions in acreages after 1960 the increased output per acre has just about compensated for acreage reductions. During this period of rapid increase in output per acre there has been a growing tendency to believe that technology has reduced the influence of weather on grain production so that we no longer need to fear shortages due to unfavorable weather. There is also a popular belief that acreage control$ fail to achieve the objective of production control, and that public funds are being wasted in storing surplus grains which we don\u27t need. There is increasing evidence, however, that a period of favorable weather interacted with technology to produce our recent high yields, and that perhaps half of the increase in yield per acre since 1950 has been due to a change to more favorable weather for grain crops. These findings have important implications in continued support for research in production technology and in the way in which we look at our surplus stocks of feed and food grains. If a period of favorable weather has been responsible for half of the increase in yields since 19501 then what can we expect if the weather trend reverses itself for a few years? Do we have periodicity in weather, and have we just passed through a run of favorable years that might be followed by a run of unfavorable years? Should we treat our surplus grains as reserves? How does our rate of growth in grain output compare with the needs of a growing world population? And of course I in the background of these questions is one big question -- how much of our recent high yields is really due to weather? To answer these important questions the Center for Agriculture and Economic Development invited outstanding authorities to present their ideas under three main headings: (1) Techniques for Evaluation of Weather Variables in Agricultural Production I (2) Periodicity in Weather Patterns: Implications in Agriculture I and (3) Weather Considerations in Agricultural Policy. The papers have been assembled in the order of their presentation under the general outline above.https://lib.dr.iastate.edu/card_reports/1021/thumbnail.jp
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