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101.
Chicks learned to find food hidden under sawdust by ground-scratching in the central position of the floor of a closed arena. When tested in an arena of identical shape but a larger area, chicks searched at 2 different locations, one corresponding to the correct distance (i.e., center) in the smaller (training) arena and the other to the actual center of the test arena. When tested in an arena of the same shape but a smaller area, chicks searched in the center of it. These results suggest that chicks are able to encode information on the absolute and relative distance of the food from the walls of the arena. After training in the presence of a landmark located at the center of the arena, animals searched at the center even after the removal of the landmark. Marked changes in the height of the walls of the arena produced some displacement in searching behavior, suggesting that chicks used the angular size of the walls to estimate distances. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Romolo Marcelli Giancarlo Bartolucci George Papaioannu Giorgio De Angelis Andrea Lucibello Emanuela Proietti Benno Margesin Flavio Giacomozzi François Deborgies 《Microsystem Technologies》2010,16(7):1111-1118
The reliability of RF MEMS switches is typically reduced by charging effects occurring in the dielectrics. The aim of this
paper is to discuss these effects, and to propose analytical and equivalent circuit models which account for most of the physical
contributions present in the structure. 相似文献
103.
Tasca Giorgio A.; Ramsay Tim; Corace Kimberly; Illing Vanessa; Bone Meagan; Bissada Hany; Balfour Louise 《Canadian Metallurgical Quarterly》2010,14(2):151
Many community- and hospital-based group treatment programs have an open enrolment, that is, a rolling admissions structure, in which a group member who drops out or successfully completes therapy is replaced by another individual. Although practically efficient and perhaps clinically useful, the interdependence of these group participants' data may result in incorrect inferences drawn from the data analyses if this interdependence is not accounted for. We present an analytic strategy that uses time varying covariates in multilevel models to illustrate a methodology to address these data analysis problems. Participants were adults with eating disorders (N = 229) who attended an average of 12 weeks of a rolling admissions group-based day hospital program during an 8-year period, and who completed a group therapy alliance measure weekly. Individual alliance to the group increased from week to week, and this growth remained significant even after controlling for the time varying level of other group members' alliance to the group. Further, the level of an individual's alliance score during any given week was positively related to the group's alliance during that week. The multilevel time varying covariate models presented here add to a very small but emerging set of analytic strategies available for researchers to address some of the hurdles to correctly analyze data from rolling admissions group-based treatment programs. Results from this study provide evidence that a group's culture is passed on and affects an individual's alliance to the group despite changes in group membership. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
Implications of attachment theory and research for the assessment and treatment of eating disorders.
In this paper, we review the research literature on attachment and eating disorders and suggest a framework for assessing and treating attachment functioning in patients with an eating disorder. Treatment outcomes for individuals with eating disorders tend to be moderate. Those with attachment-associated insecurities are likely to be the least to benefit from current symptom-focused therapies. We describe the common attachment categories (secure, avoidant, anxious), and then describe domains of attachment functioning within each category: affect regulation, interpersonal style, coherence of mind, and reflective functioning. We also note the impact of disorganized mental states related to loss or trauma. Assessing these domains of attachment functioning can guide focused interventions in the psychotherapy of eating disorders. Case examples are presented to illustrate assessment, case formulation, and group psychotherapy of eating disorders that are informed by attachment theory. Tailoring treatments to improve attachment functioning for patients with an eating disorder will likely result in better outcomes for those suffering from these particularly burdensome disorders. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
105.
In the last years many studies have been carried out on the possible improvements of the in situ thermal conductance measurement; as well known, this has to be derived by recorded values of temperatures and heat fluxes. A big effort has been addressed in the implementation and comparison of different analysis methods. The aim of this paper is to widen the existent literature in the study of the influence of different kinds of input data on the final result. First the problem of analysing input data with significant drift in temperature is considered, adopting both nominal clean and noise affected data. Then the effect due to the presence of the Heat Flux Meter (HFM) on the thermal field of the testing element has been analysed, as well as the possibility of recording HFM surface temperature. These studies are based on Finite Element Method (FEM) simulations; both nominal clean and noise affected data have been considered as input. Finally, a difference in emissivity between the heat flux meter and internal plaster surface has been analysed by means of FEM simulations based on nominal clean data. An overall estimation of the occurred deviations in the different cases is shown. 相似文献
106.
Serena Tolin Gabriella PasiniAndrea Curioni Giorgio Arrigoni Antonio MasiFederica Mainente Barbara Simonato 《Food Control》2012,23(1):87-94
The need of label declaration for egg proteins is temporarily suspended when they are used as a processing aid in winemaking, because of a lack of scientific data concerning their actual permanence as residual proteins in fined wines.The possibility to detect residual egg proteins in red wines treated with a commercial egg white preparation was studied. By using an immunochemical method residual egg proteins were detected in the experimental red wines only for doses of fining agent of 50 g/hL or higher, whereas no residual proteins were detected by this system in a commercial red wine.A simple method based on the recovery and identification of the wine fining proteins by liquid chromatography coupled with tandem MS (LC-MS/MS) in a gel-free approach was developed. This allowed the detection of egg proteins in red wines fined down to 5 g/hL of commercial egg white preparation and also in the commercial red wine. These results indicate that the analytical approach here suggested is superior to the immunochemical methods in detecting egg proteins in wines. Therefore hypersensitivity reactions after consumption of wines treated with egg proteins can be a real risk for egg-allergic people. 相似文献
107.
In this article, we propose an agent‐based approach for managing e‐commerce activities. In our approach, an agent is present in each e‐commerce site, managing the information stored there. In addition, another agent is associated with each customer, handling his/her profile. The proposed approach is based on the use of a particular conceptual model called the Behaviour‐Semantic Distance and Relevance (B‐SDR) network, which is capable of uniformly representing and handling information stored in e‐commerce sites and customer profiles. The capabilities of the B‐SDR network model are exploited to let customer and site agents cooperate in such a way in order to support a customer in identifying, whenever he/she accesses an e‐commerce site, those products and services present in the site itself and for better matching his/her interests. The approach has been implemented in a prototype in which its functionalities are discussed here also. © 2004 Wiley Periodicals, Inc. 相似文献
108.
Biglieri Ezio Caire Giuseppe Taricco Giorgio Ventura-Traveset Javier 《Wireless Personal Communications》1998,6(1-2):39-68
In this paper, the performance of coding and diversity in narrowband wireless cellular systems affected by fading, shadowing and co-channel interference is analyzed. We consider low-order diversity, that can be practically realized for both coherent and differential phase shift keying. We assume that the shadowing random processes affecting all transmitted signals do not vary appreciably over the transmission duration. Fading, on the contrary, is assumed to vary more rapidly. Our main focus here is on outage probability. After choosing a performance indicator, its expectation is taken with respect to fading and co-channel interference, conditionally on shadowing. Hence, the resulting average performance indicator is a random variable. The probability that this random variable exceeds a specified threshold defines the outage probability. We consider as performance indicators (i) the channel cut-off rate R0 and (ii) the bit error rate Pb of an actual coded scheme. As we are interested in interference-limited, rather than power-limited systems, we evaluate both R0 and Pb for very high signal-to-noise ratios. Results are parameterized by the frequency reuse factor and the diversity order. 相似文献
109.
Social discrimination in male and female domestic chicks (Gallus gallus) was investigated by using (1) latencies of approach response, (2) simultaneous free choice, and (3) intersubject aggressive-pecking tests. In approach-response tests, females showed shorter latencies when tested with cagemates than when tested with strangers, whereas males showed shorter latencies when tested with strangers than when tested with cagemates. In simultaneous-choice tests, females spent more time near a cagemate, whereas males spent more time near a strange chick. In aggressive-pecking tests, both sexes pecked more at strangers than at cagemates; aggressive pecking at strangers, however, was higher in males than in females. It is argued that gender effects in social discrimination can be accounted for in terms of stronger social attachment in females and aggressive responses in males. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
Vallortigara Giorgio; Cailotto Maurizio; Zanforlin Mario 《Canadian Metallurgical Quarterly》1990,104(4):361
Male and female chicks (Gallus gallus) were trained at 4 days old to run along a corridor to reach a goal box that contained either cagemates (social reinforcement) or food (nonsocial reinforcement). Females ran faster when social reinforcement was used, whereas males ran faster with nonsocial reinforcement. When social reinforcement was used with a V-shaped runway, in which chicks had to proceed toward the goal object in an indirect fashion, sex differences were reversed. The results may be due to stronger social reinstatement tendencies in females than in males: Higher levels of social motivation facilitate behavioral performance when the task is easy (straight runway) and inhibit it when the task is difficult (V-shaped runway). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献