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Selected AbstractsInformed dispersal, heterogeneity in animal dispersal syndromes and the dynamics of spatially structured populationsECOLOGY LETTERS, Issue 3 2009Jean Clobert Abstract There is accumulating evidence that individuals leave their natal area and select a breeding habitat non-randomly by relying upon information about their natal and future breeding environments. This variation in dispersal is not only based on external information (condition dependence) but also depends upon the internal state of individuals (phenotype dependence). As a consequence, not all dispersers are of the same quality or search for the same habitats. In addition, the individual's state is characterized by morphological, physiological or behavioural attributes that might themselves serve as a cue altering the habitat choice of conspecifics. These combined effects of internal and external information have the potential to generate complex movement patterns and could influence population dynamics and colonization processes. Here, we highlight three particular processes that link condition-dependent dispersal, phenotype-dependent dispersal and habitat choice strategies: (1) the relationship between the cause of departure and the dispersers' phenotype; (2) the relationship between the cause of departure and the settlement behaviour and (3) the concept of informed dispersal, where individuals gather and transfer information before and during their movements through the landscape. We review the empirical evidence for these processes with a special emphasis on vertebrate and arthropod model systems, and present case studies that have quantified the impacts of these processes on spatially structured population dynamics. We also discuss recent literature providing strong evidence that individual variation in dispersal has an important impact on both reinforcement and colonization success and therefore must be taken into account when predicting ecological responses to global warming and habitat fragmentation. [source] Behavior selection of mobile robot based on integration of multimodal informationELECTRICAL ENGINEERING IN JAPAN, Issue 2 2007Bin Chen Abstract Recently, biologically inspired robots have been developed to acquire the capacity for directing visual attention to salient stimulus generated from the audiovisual environment. For the purpose of realizing this behavior, a general method is to calculate saliency maps to represent how much the external information attracts the robot's visual attention, where the audiovisual information and robot's motion status should be involved. In this paper, we represent a visual attention model where three modalities,audio information, visual information, and robot's motor status,are considered, because previous research has not considered all of them. First, we introduce a 2D density map, on which the value denotes how much the robot pays attention to each spatial location. Then we model the attention density using a Bayesian network where the robot's motion statuses are involved. Next, the information from both audio and visual modalities is integrated with the attention density map in integrate-fire neurons. The robot can direct its attention to the locations where the integrate-fire neurons are fired. Finally, the visual attention model is applied to make the robot select the visual information from the environment, and react to the content selected. Experimental results show that it is possible for robots to acquire the visual information related to their behaviors by using the attention model considering motion statuses. The robot can select its behaviors to adapt to the dynamic environment as well as to switch to another task according to the recognition results of visual attention. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 158(2): 39,48, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20335 [source] Inter-rater and test,retest reliability of three contingent valuation question formats in south-east NigeriaHEALTH ECONOMICS, Issue 5 2005Obinna Onwujekwe Abstract This paper examines the inter-rater and test,retest reliability of willingness to pay (WTP) for insecticide-treated mosquito nets and net re-treatment using the bidding game (BG), binary with follow-up (BWFU) and a novel structured haggling technique (SH). Inter-rater reliability was evaluated by having two sets of interviewers administer questionnaires to 109 (BG), 110 (BWFU) and 103 (SH) randomly selected household heads. Test,retest reliability was investigated by repeating interviews on 146 (BG), 161 (BWFU) and 139 (SH) household heads one month after an initial survey. Data analysis used testing of means, Spearman's correlation and Pearson's correlation coefficient for test of reliability, while non-parametric analysis was used to determine factors causing a variation in WTP. The study was conducted in Southeast Nigeria. Inter-rater reliability coefficients were estimated for the individual's WTP for own nets, WTP for others and WTP for re-treatment. Using WTP for own nets as the best reliability estimate, the coefficients were high at values of 0.77 (C.I. 0.72,0.86), 0.75 (C.I. 0.64,0.81) and 0.74 (C.I. 0.63,0.82) in the BG, BWFU and SH, respectively. In test,retest reliability coefficients, the coefficients for WTP for own nets were low-to-moderate at values of 0.51 (C.I. 0.40,0.62), 0.41 (C.I. 0.28,0.53) and 0.56 (C.I. 0.41,0.65) for the BG, BWFU and SH groups, respectively. Factors such as gender, change in income, unplanned expenditures, stated WTP in first survey, time-to-think, external information, and subjecting respondents to more than one interview explained the lower test,retest reliability coefficients. We conclude that the CVM was reliable in the study area and the question formats had similar levels of reliability. The lower coefficients in the test,retest reliability were due to the influence of factors affecting demand that had changed in the intervening period. Standard formats for determining reliability within CVM should be developed for easy comparison of results from different studies. Copyright © 2004 John Wiley & Sons, Ltd. [source] A look inside ,black box' hydrograph separation models: a study at the Hydrohill catchmentHYDROLOGICAL PROCESSES, Issue 10 2001Carol Kendall Abstract Runoff sources and dominant flowpaths are still poorly understood in most catchments; consequently, most hydrograph separations are essentially ,black box' models where only external information is used. The well-instrumented 490 m2 Hydrohill artificial grassland catchment located near Nanjing (China) was used to examine internal catchment processes. Since groundwater levels never reach the soil surface at this site, two physically distinct flowpaths can unambiguously be defined: surface and subsurface runoff. This study combines hydrometric, isotopic and geochemical approaches to investigating the relations between the chloride, silica, and oxygen isotopic compositions of subsurface waters and rainfall. During a 120 mm storm over a 24 h period in 1989, 55% of event water input infiltrated and added to soil water storage; the remainder ran off as infiltration-excess overland flow. Only about 3,5% of the pre-event water was displaced out of the catchment by in-storm rainfall. About 80% of the total flow was quickflow, and 10% of the total flow was pre-event water, mostly derived from saturated flow from deeper soils. Rain water with high ,18O values from the beginning of the storm appeared to be preferentially stored in shallow soils. Groundwater at the end of the storm shows a wide range of isotopic and chemical compositions, primarily reflecting the heterogeneous distribution of the new and mixed pore waters. High chloride and silica concentrations in quickflow runoff derived from event water indicate that these species are not suitable conservative tracers of either water sources or flowpaths in this catchment. Determining the proportion of event water alone does not constrain the possible hydrologic mechanisms sufficiently to distinguish subsurface and surface flowpaths uniquely, even in this highly controlled artificial catchment. We reconcile these findings with a perceptual model of stormflow sources and flowpaths that explicitly accounts for water, isotopic, and chemical mass balance. Copyright © 2001 John Wiley & Sons, Ltd. [source] Marketing information systems in tourism and hospitality small- and medium-sized enterprises: a study of Internet use for market intelligenceINTERNATIONAL JOURNAL OF TOURISM RESEARCH, Issue 4 2001Emma Wood Abstract This study investigates the nature of marketing information systems (MkIS) within small- and medium-sized enterprises (SMEs) and focuses on the importance of external information and market intelligence. The sources of market intelligence are investigated with particular emphasis on understanding the usefulness of the Internet for external information gathering. The empirical research to support the study uses survey methods to investigate marketing information systems, market intelligence and Internet use within hospitality and tourism SMEs in the Yorkshire and Humber region. The findings indicate that SMEs in this sector make use of informal marketing information systems which mainly concentrate on internal and immediate operating environment data. Important wider market intelligence is underutilised owing mainly to the resource constraints of these smaller businesses. The Internet has not yet been recognised as an important source for market intelligence despite having the benefits of providing much of the necessary data more quickly and at a lower cost than many other sources. Copyright © 2001 John Wiley & Sons, Ltd. [source] A comparison of methods for analysing regression models with both spectral and designed variablesJOURNAL OF CHEMOMETRICS, Issue 10 2004Kjetil Jørgensen Abstract In many situations one performs designed experiments to find the relationship between a set of explanatory variables and one or more responses. Often there are other factors that influence the results in addition to the factors that are included in the design. To obtain information about these so-called nuisance factors, one can sometimes measure them using spectroscopic methods. The question then is how to analyze this kind of data, i.e. a combination of an orthogonal design matrix and a spectroscopic matrix with hundreds of highly collinear variables. In this paper we introduce a method that is an iterative combination of partial least squares (PLS) and ordinary least squares (OLS) and compare its performance with other methods such as direct PLS, OLS and a combination of principal component analysis and least squares. The methods are compared using two real data sets and using simulated data. The results show that the incorporation of external information from spectroscopic measurements gives more information from the experiment and lower variance in the parameter estimates. We also find that the introduced algorithm separates the information from the spectral and design matrices in a nice way. It also has some advantages over PLS in showing lower bias and being less influenced by the relative weighting of the design and spectroscopic variables. Copyright © 2005 John Wiley & Sons, Ltd. [source] CONSUMER ASSESSMENT OF THE SAFETY OF RESTAURANTS: THE ROLE OF INSPECTION NOTICES AND OTHER INFORMATION CUESJOURNAL OF FOOD SAFETY, Issue 4 2006SPENCER HENSON ABSTRACT This paper explores the ways in which consumers assess the safety of food in restaurants and other eating-out establishments, and the resulting impact on restaurant choice. The analysis builds on the existing literature on restaurant choice more generally and a growing body of studies on the impact of official inspection information on the perceived safety of restaurants. Based on a two-stage consumer study in the City of Hamilton in Ontario, Canada, involving focus groups and a postal survey, the research highlights how consumers base their assessment of food safety in restaurants using a range of visible indicators of the experience and/or credence characteristics associated with foodborne illness. These include their observed judgments of restaurant hygiene, the overall quality of the restaurant, external information, including official inspection certificates, and the level of patronage. The use of these broad groups of indicators varies across consumer subgroups according to gender, age, level of education and recollections of past incidences when a restaurant was closed and/or convicted for food safety reasons. [source] Latest news and product developmentsPRESCRIBER, Issue 2 2007Article first published online: 1 MAR 200 Venlafaxine: same suicide risk Venlafaxine (Efexor) is probably not associated with a higher risk of suicide than citalopram, fluoxetine or dosulepin, even when prescribed for patients at higher risk, according to an analysis of the UK General Practice Research Database (BMJ, doi:10.1136/bmj.39041.445104.BE. Published 12 December 2006). The retrospective cohort study found that venlafaxine was associated with a significantly higher risk of completed and attempted suicide in adults than the other antidepressants but, after adjusting for risk factors, the authors concluded that much, if not all, of the difference could be explained by confounding. Raised glucose with thiazides not clinically significant? A new analysis of the ALLHAT trial suggests that the small increase in blood glucose levels associated with long-term thiazide therapy is not associated with an increased risk of cardiovascular events (Arch Intern Med 2006;166:2191-201). The ALLHAT trial compared cardiovascular outcomes in over 18 000 patients with hypertension who were treated with chlortali- done (Hygroton), amlodipine and lisinopril. After two years, fasting blood glucose had increased in all groups (by 0.47, 0.31 and 0.19mmol per litre respectively); compared with chlortalidone, the odds of developing diabetes were 45 per cent lower with lisinopril and 27 per cent lower with amlodipine. However, there was no significant link between fasting blood glucose levels and cardiovascular events, end-stage renal disease or death; developing diabetes was associated with an increased risk of CHD overall but this was not statistically significant for chlortalidone in particular. Withdrawing alendronate after five years' treatment Discontinuing treatment of osteoporosis with alendronate after five years does not significantly increase fracture risk for many women, a US study has shown (J Am Med Assoc 2006;296:2927-38). In this five-year extension to the Fracture Intervention Trial, 1099 women who had taken alendronate for five years were randomised to continue treatment or switch to placebo for a further five years. In those taking placebo, bone mineral density decreased by 2.4 per cent at the hip and 3.7 per cent in the spine but remained above pre- treatment levels. Continuing with alendronate was associated with a lower risk of clinical vertebral fractures (2.4 vs 5.3 per cent) but no significant reduction in morphometric vertebral fractures (9.8 vs 11.3 per cent respectively). The cumulative risk of nonvertebral fractures was 19 per cent in each group. The authors conclude that women at very high risk of clinical vertebral fractures may benefit from continuing alendronate, but for many discontinuation does not appear to increase fracture risk. Instructions on labels Patients with low levels of literacy are at high risk of not understanding medicines labelling (Ann Intern Med 2006;145:887-94). In 395 English-speaking adults, 71 per cent correctly repeated simple label instructions, but only 35 per cent could demonstrate the correct number of tablets involved. Low literacy levels were associated with a twofold increased risk of misunderstanding labelling. Statins campaign The National Prescribing Centre (NPC) has launched a campaign to increase prescribing of low-cost statins. Resources available from its website at www.npc.co.uk/statins.htm are divided into four categories: policy and guidance, therapeutics, implementation resources and monitoring tools. Formats include documents and case studies, Powerpoint presentations and E-learning workshops. patients feeling rested on waking and daytime functioning. The Z-drugs were also believed to cause fewer adverse effects. GPs believe in ,Z' drugs A survey of GPs in Lincolnshire has revealed that their beliefs about nonbenzodiazepine hypnotics are inconsistent with NICE guidance and published evidence (Br J Gen Pract 2006; 56:964-7). Responders believed that zaleplon (Sonata), zopiclone and zolpidem were superior to benzodiazepines in increasing sleep time, patients feeling rested on waking and daytime functioning. The Z-drugs were also believed to cause fewer adverse effects. The authors note that, while benzodiazepine prescribing is declining, that of the Z-drugs is increasing, and they suggest this may be explained by misplaced beliefs about their relative effectiveness and safety. Pharmacy EHC guidance Pharmacists can supply emergency hormonal contraception (EHC) in advance but should consider when it is clinically appropriate to do so, according to revised guidance from the Royal Pharmaceutical Society. The move follows support for advance supply from the British Pregnancy Advisory Service and Marie Stopes International. Pharmacists are advised to decline repeated requests and recommend contraception instead, and to counsel users on using EHC safely and appropriately. More support from NICE NICE has developed two databases to support implementation of its recommendations. The shared learning database (www.nice.org.uk/ sharedlearning) includes experiences of implementing NICE guidance. The second, known as ERNIE (Evaluation and Review of NICE Implementation Evidence), includes data provided by NICE on uptake of its advice and external information (www.nice.org.uk/ernie). Mental health briefings The DoH (www.dh.gov.uk) has published several briefing documents to explain the main changes to mental health legislation, covering professional roles, criteria for detention and supervised community treatment (SCT). SCT applies to patients with a stable chronic mental disorder who have been discharged from hospital and who, but for their treatment, may pose a risk to themselves or others. Patients remain the responsibility of the mental health team. Copyright © 2007 Wiley Interface Ltd [source] A parallel and distributed-processing model of joint attention, social cognition and autismAUTISM RESEARCH, Issue 1 2009Peter Mundy Abstract The impaired development of joint attention is a cardinal feature of autism. Therefore, understanding the nature of joint attention is central to research on this disorder. Joint attention may be best defined in terms of an information-processing system that begins to develop by 4,6 months of age. This system integrates the parallel processing of internal information about one's own visual attention with external information about the visual attention of other people. This type of joint encoding of information about self and other attention requires the activation of a distributed anterior and posterior cortical attention network. Genetic regulation, in conjunction with self-organizing behavioral activity, guides the development of functional connectivity in this network. With practice in infancy the joint processing of self,other attention becomes automatically engaged as an executive function. It can be argued that this executive joint attention is fundamental to human learning as well as the development of symbolic thought, social cognition and social competence throughout the life span. One advantage of this parallel and distributed-processing model of joint attention is that it directly connects theory on social pathology to a range of phenomena in autism associated with neural connectivity, constructivist and connectionist models of cognitive development, early intervention, activity-dependent gene expression and atypical ocular motor control. [source] | ||||||||||||||||