637 research outputs found
Global Production Increased by Spatial Heterogeneity in a Population Dynamics Model
Spatial and temporal heterogeneity are often described as important factors having a strong impact on biodiversity. The effect of heterogeneity is in most cases analyzed by the response of biotic interactions such as competition of predation. It may also modify intrinsic population properties such as growth rate. Most of the studies are theoretic since it is often difficult to manipulate spatial heterogeneity in practice. Despite the large number of studies dealing with this topics, it is still difficult to understand how the heterogeneity affects populations dynamics. On the basis of a very simple model, this paper aims to explicitly provide a simple mechanism which can explain why spatial heterogeneity may be a favorable factor for production.We consider a two patch model and a logistic growth is assumed on each patch. A general condition on the migration rates and the local subpopulation growth rates is provided under which the total carrying capacity is higher than the sum of the local carrying capacities, which is not intuitive. As we illustrate, this result is robust under stochastic perturbations
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Letter processing and font information during reading: beyond distinctiveness, where vision meets design
Letter identification is a critical front end of the
reading process. In general, conceptualizations of the identification process have emphasized arbitrary sets of distinctive features. However, a richer view of letter processing incorporates principles from the field of type design, including an emphasis on uniformities across letters within a font. The importance of uniformities is supported by a small body of research indicating that consistency of font increases letter identification efficiency. We review design concepts and the relevant literature, with the goal of stimulating further thinking about letter processing during reading
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Does urbanization explain differences in interactions between an insect herbivore and its natural enemies and mutualists?
Urbanization can alter the composition of arthropod communities. However, little is known about how urbanization affects ecological interactions. Using experimental colonies of the black bean aphid Aphis fabae Scopoli reared on Vicia faba L, we asked if patterns of predator-prey, host-parasitoid and ant-aphid mutualisms varied along an urbanization gradient across a large town in southern England. We recorded the presence of naturally occurring predators, parasitoid wasps and mutualistic ants together with aphid abundance. We examined how biotic (green areas and plant richness) and abiotic features (impervious surfaces and distance to town center) affected (1) aphid colony size, (2) the likelihood of finding predators, mutualistic ants and aphid mummies (indicating the presence of parasitoids), and (3) how the interplay among these factors affected patterns of parasitoid attack, predator abundance, mutualistic interactions and aphid abundance. The best model to predict aphid abundance was the number of mutualistic ants attending the colonies. Aphid predators responded negatively to both the proportion of impervious surfaces and to the number of mutualistic ants farming the colonies, and positively to aphid population size, whereas parasitized aphids were found in colonies with higher numbers of aphids and ants. The number of mutualistic ants attending was positively associated with aphid colony size and negatively with the number of aphid predators. Our findings suggest that for insect-natural enemy interactions, urbanization may affect some groups, while not influencing others, and that local effects (mutualists, host plant presence) will also be key determinants of how urban ecological communities are formed
COMPARISON OF ANN AND CBR MODELS FOR EARLY COST PREDICTION OF STRUCTURAL SYSTEMS
Reasonably accurate cost estimation of the structural system is quite desirable at the early stages of the design process of a construction project. However, the numerous interactions among the many cost-variables make the prediction difficult. Artificial neural networks (ANN) and case-based reasoning (CBR) are reported to overcome this difficulty. This paper presents a comparison of CBR and ANN augmented by genetic algorithms (GA) conducted by using spreadsheet simulations. GA was used to determine the optimum weights for the ANN and CBR models. The cost data of twenty-nine actual cases of residential building projects were used as an example application. Two different sets of cases were randomly selected from the data set for training and testing purposes. Prediction rates of 84% in the GA/CBR study and 89% in the GA/ANN study were obtained. The advantages and disadvantages of the two approaches are discussed in the light of the experiments and the findings. It appears that GA/ANN is a more suitable model for this example of cost estimation where the prediction of numerical values is required and only a limited number of cases exist. The integration of GA into CBR and ANN in a spreadsheet format is likely to improve the prediction rates
Materializing digital collecting: an extended view of digital materiality
If digital objects are abundant and ubiquitous, why should consumers pay for, much less collect them? The qualities of digital code present numerous challenges for collecting, yet digital collecting can and does occur. We explore the role of companies in constructing digital consumption objects that encourage and support collecting behaviours, identifying material configuration techniques that materialise these objects as elusive and authentic. Such techniques, we argue, may facilitate those pleasures of collecting otherwise absent in the digital realm. We extend theories of collecting by highlighting the role of objects and the companies that construct them in materialising digital collecting. More broadly, we extend theories of digital materiality by highlighting processes of digital material configuration that occur in the pre-objectification phase of materialisation, acknowledging the role of marketing and design in shaping the qualities exhibited by digital consumption objects and consequently related consumption behaviours and experiences
Patients' experiences with cancer care in Switzerland: Results of a multicentre cross-sectional survey.
The objectives were to describe patients' experiences of cancer care in Switzerland and explore the variation of these experiences by type of cancer.
The Swiss Cancer Patient Experiences (SCAPE) study was a cross-sectional, multicentre survey conducted in 2018. Adult patients (n = 7145) with breast, prostate, lung, colorectal, skin or haematological cancer from four large hospitals in French-speaking Switzerland were invited to complete a survey. Logistic regressions were used to assess whether experiences varied according to cancer type, adjusting for confounders.
Of the 3121 persons who returned the survey (44% response rate), 2755 reporting an eligible cancer were included in the analyses. Participants' average score for overall care was 8.5 out of a maximum score of 10. Higher rates of positive experiences were found for nurse consultations (94%), diagnostic tests (85%) and inpatient care (82%). Lower positive responses were reported for support for people with cancer (70%), treatment decisions (66%), diagnosis (65%) and home care (55%). We observed non-systematic differences in experiences of care by cancer type.
This large study identified that cancer patient experiences can be improved in relation to communication, information and supportive care aspects. Improvement efforts should target these areas of care to enhance responsiveness of cancer care
Nurse-Led Medicines' Monitoring for Patients with Dementia in Care Homes: A Pragmatic Cohort Stepped Wedge Cluster Randomised Trial
People with dementia are susceptible to adverse drug reactions (ADRs). However, they are not always closely monitored for potential problems relating to their medicines: structured nurse-led ADR Profiles have the potential to address this care gap. We aimed to assess the number and nature of clinical problems identified and addressed and changes in prescribing following introduction of nurse-led medicines' monitoring.Pragmatic cohort stepped-wedge cluster Randomised Controlled Trial (RCT) of structured nurse-led medicines' monitoring versus usual care.Five UK private sector care homes.41 service users, taking at least one antipsychotic, antidepressant or anti-epileptic medicine.Nurses completed the West Wales ADR (WWADR) Profile for Mental Health Medicines with each participant according to trial step.Problems addressed and changes in medicines prescribed.Information was collected from participants' notes before randomisation and after each of five monthly trial steps. The impact of the Profile on problems found, actions taken and reduction in mental health medicines was explored in multivariate analyses, accounting for data collection step and site.Five of 10 sites and 43 of 49 service users approached participated. Profile administration increased the number of problems addressed from a mean of 6.02 [SD 2.92] to 9.86 [4.48], effect size 3.84, 95% CI 2.57-4.11, P <0.001. For example, pain was more likely to be treated (adjusted Odds Ratio [aOR] 3.84, 1.78-8.30), and more patients attended dentists and opticians (aOR 52.76 [11.80-235.90] and 5.12 [1.45-18.03] respectively). Profile use was associated with reduction in mental health medicines (aOR 4.45, 1.15-17.22).The WWADR Profile for Mental Health Medicines can improve the quality and safety of care, and warrants further investigation as a strategy to mitigate the known adverse effects of prescribed medicines.ISRCTN 48133332
Effect of measuring patient satisfaction during or after staying in a psychiatric hospital
BACKGROUND: Patient satisfaction surveys are commonly conducted to evaluate health care quality. However, little is known about the impact of the time point of survey administration on the level of satisfaction, questionnaire acceptability, and costs, especially for inpatient psychiatric care. AIMS: To assess whether inpatient satisfaction, questionnaire acceptability, and total costs of study differ according to the time point of questionnaire administration for inpatient psychiatric care. METHOD AND SAMPLE: Inpatients completed the ©Saphora-Psy, a French validated tool measuring satisfaction with care with 35 items assessing 7 dimensions of care, 2-3 days before leaving the ward (first phase). Four to eight weeks after discharge, patients received the same instrument at home (second phase). Time needed to fill the questionnaire and items assessing its acceptability were requested. RESULTS: Only fifty of 104 inpatients in the acute psychiatric hospital, aged >18, who completed the first questionnaire, participated to the second phase, although they all agreed to complete it twice. The participation rate during the hospital stay was 47%. Acceptability did not differ significantly. The mean proportion of missing values was slightly higher after hospital stay (3.84%) than during hospital stay (3.52%), while the number of manuscript comments was identical (n=13). Global evaluation of the questionnaire was similar when administered after or before discharge (excellent/very good : 41% and 42% respectively). General satisfaction with care was rated higher when measured during (vs after) hospital stay. Satisfaction was significantly lower when measured after discharge on four items: nursing staff's empathy (p=0.02) and communication about care (p=0.03), smoking directives (p=0.01), and information regarding treatment after discharge (p=0.01). Costs were about eight times higher during the first phase. CONCLUSIONS: Satisfaction appeared to vary slightly according to the time point of questionnaire administration, with higher ratings measured during hospital stay. In terms of acceptability, the surveys offered identical rates. The costs were much higher during the first phase, due to the hot pursuit of patients about to leave the hospital. [Authors]]]>
Patient Satisfaction; Quality of Health Care; Questionnaires; Hospitals, Psychiatric; Hospitalization
eng
oai:serval.unil.ch:BIB_8CB02C4CD096
2022-05-07T01:22:28Z
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https://serval.unil.ch/notice/serval:BIB_8CB02C4CD096
Change in defense mechanisms and coping patterns during the course of 2-year-long psychotherapy and psychoanalysis for recurrent depression: a pilot study of a randomized controlled trial.
info:doi:10.1097/NMD.0b013e3182982982
info:eu-repo/semantics/altIdentifier/doi/10.1097/NMD.0b013e3182982982
info:eu-repo/semantics/altIdentifier/pmid/23817160
Kramer, U.
de Roten, Y.
Perry, J.C.
Despland, J.N.
info:eu-repo/semantics/article
article
2013
Journal of Nervous and Mental Disease, vol. 201, no. 7, pp. 614-620
info:eu-repo/semantics/altIdentifier/eissn/1539-736X
urn:issn:0022-3018
<