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Samples Used (sample + used)
Selected AbstractsEmergency Department Utilization by Noninstitutionalized EldersACADEMIC EMERGENCY MEDICINE, Issue 3 2001Manish N. Shah MD Abstract. Objectives: To the best of the authors knowledge, no nationally representative, population-based study has characterized the proportion of elders using the emergency department (ED) and factors associated with ED use by elders. This article describes the proportion of elder Medicare beneficiaries using the ED and identifies attributes associated with elder ED users as compared with nonusers. Methods: The 1993 Medicare Current Beneficiary Survey was used, a national, population-based, cross-sectional survey of Medicare beneficiaries linked with Medicare claims data. The study population was limited to 9,784 noninstitutionalized individuals aged 66 years or older. The Andersen model of health service utilization was used, which explains variation in ED use through a combination of predisposing (demographic and social), enabling (access to care), and need (comorbidity and health status) characteristics. Results: Eighteen percent of the sample used the ED at least once during 1993. Univariate analysis showed ED users were older; were less educated and lived alone; had lower income and higher Charlson Comorbidity Index scores; and were less satisfied with their ability to access care than nonusers (p < 0.01, chi-square). Logistic regression identified older age, less education, living alone, higher comorbidity scores, worse reported health, and increased difficulties with activities of daily living as factors associated with ED use (p < 0.05). Need characteristics predicted ED use with the greatest accuracy. Conclusions: The proportion of elder ED users is slightly higher than previously reported among Medicare beneficiaries. Need (comorbidity and health status) characteristics predict ED utilization with the greatest accuracy. [source] The Impact of Trade Liberalization on Regional Disparities in MexicoGROWTH AND CHANGE, Issue 1 2002Javier Sánchez-Reaza After a long period of industrialization based on import substitution (ISI), Mexico started to open up its economy by accessing the General Agreement on Tariffs and Trade (GATT) in 1986. The export-promotion strategy was transformed into one of regional integration with the signing of the North American Free Trade Agreement (NAFTA) in 1994. The paper explores the impact of the opening of the economy on regional disparities in Mexico using , and ,-convergence analyses. Four different samples have been employed to control for possible data bias linked to the inclusion of oil-producing and maquiladora-based states. The results show that whereas the final stages of the ISI period were dominated by convergence trends, trade liberalization (GATT) and economic integration (NAFTA) have led to divergence. In particular, the NAFTA period is related to divergence regardless of the type of analysis chosen and the sample used. [source] Assessment of grape skin hardness by a puncture testJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 9 2008Hend Letaief Abstract BACKGROUND: The release of grape components during wine making might be related to the mechanical properties of the skin, in particular its hardness. Samples from three varieties collected during the 2005 vintage season in Piedmont, Italy, were tested for their skin hardness using a texture analyser. The goal was to understand the statistical interactions between three factors,variety, cluster position and puncture point,and their influence on the grape skin hardness. A discussion on the relationship between the size of the sample used and the confidence level is also provided. RESULTS: Results of the ANOVA test showed that there is an interaction between the variety and the puncture point when measuring the skin hardness with the break energy. The position of the berry on the cluster does not affect the berry skin break energy. We also show that a sample size depend on the variety tested. CONCLUSION: The break energy is more useful in understanding the effect of the three factors on the skin hardness. Other factors that might affect the puncture test applied to grapes need to be studied in the future and the usefulness of the test in winemaking will need to be further developed. Copyright © 2008 Society of Chemical Industry [source] Characterization by mass spectrometry of an unknown polysiloxane sample used under uncontrolled medical conditions for cosmetic surgeryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 21 2008Cédric Schneider For a complete understanding of the raw material used for cosmetic surgery under uncontrolled medical conditions, an unknown sample of polydimethylsiloxanes has been investigated utilizing a combination of analytical techniques: pyrolysis/gas chromatography/mass spectrometry (Py/GC/MS), electrospray ionization (ESI)-MS, matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF)MS, and liquid chromatography (LC)/MS. Among these techniques, the LC/APCI-MS coupling allowed the fastest and more effective analysis. In addition, the complexity of the mass spectra deduced from these LC/MS experiments was simplified compared to the mass spectra obtained by MALDI-TOF. In this work, we have demonstrated how the LC/APCI-MS coupling applied to polydimethylsiloxane samples permits the full characterization of samples where end groups of different nature can be present in very small quantities. Copyright © 2008 John Wiley & Sons, Ltd. [source] A Consistent Poverty Approach to Assessing the Sensitivity of Income Poverty Measures and TrendsTHE AUSTRALIAN ECONOMIC REVIEW, Issue 4 2008Peter Saunders This paper examines the sensitivity of estimates of income poverty rates and trends to variations in the poverty line and to whether or not certain households are included or excluded from the sample used to estimate poverty. The approach draws on the concept of consistent poverty, which has been used to identify those with incomes below the poverty line who also experience deprivation. Our approach involves excluding households with incomes below the poverty line if they report zero or negative income or are self-employed, have expenditure well in excess of their income, have substantial wealth holdings, or if they do not report having experienced financial stress over the past year. The combined impact of all four exclusions is to reduce the half-median income poverty rate from 9.9 per cent to 5.4 per cent, but also suggests that poverty increased by more over the decade to 2003,04 than the original estimates indicate. [source] Flow Cytometric Sorting of Fresh and Frozen-Thawed Spermatozoa in the Western Lowland Gorilla (Gorilla gorilla gorilla)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 4 2005J.K. O'Brien Abstract We adapted flow cytometry technology for high-purity sorting of X chromosome-bearing spermatozoa in the western lowland gorilla (Gorilla gorilla gorilla). Our objectives were to develop methodologies for liquid storage of semen prior to sorting, sorting of liquid-stored and frozen-thawed spermatozoa, and assessment of sorting accuracy. In study 1, the in vitro sperm characteristics of gorilla ejaculates from one male were unchanged (P>0.05) after 8 hr of liquid storage at 15°C in a non-egg yolk diluent (HEPES-buffered modified Tyrode's medium). In study 2, we examined the efficacy of sorting fresh and frozen-thawed spermatozoa using human spermatozoa as a model for gorilla spermatozoa. Ejaculates from one male were split into fresh and frozen aliquots. X-enriched samples derived from both fresh and frozen-thawed human semen were of high purity, as determined by fluorescence in situ hybridization (FISH; 90.7%±2.3%, overall), and contained a high proportion of morphologically normal spermatozoa (86.0%±1.0%, overall). In study 3, we processed liquid-stored semen from two gorillas for sorting using a modification of methods for human spermatozoa. The sort rate for enrichment of X-bearing spermatozoa was 7.3±2.5 spermatozoa per second. The X-enriched samples were of high purity (single-sperm PCR: 83.7%) and normal morphology (79.0%±3.9%). In study 4 we examined frozen-thawed gorilla semen, and the sort rate (8.3±2.9 X-bearing sperm/sec), purity (89.7%), and normal morphology (81.4%±3.4%) were comparable to those of liquid-stored semen. Depending on the male and the type of sample used (fresh or frozen-thawed), 0.8,2.2% of gorilla spermatozoa in the processed ejaculate were present in the X-enriched sample. These results demonstrate that fresh or frozen-thawed gorilla spermatozoa can be flow cytometrically sorted into samples enriched for X-bearing spermatozoa. Am. J. Primatol. 66:297,315, 2005. © 2005 Wiley-Liss, Inc. [source] A Generalized Discriminant Rule When Training Population and Test Population Differ on Their Descriptive ParametersBIOMETRICS, Issue 2 2002Christophe Biernacki Summary. Standard discriminant analysis methods make the assumption that both the labeled sample used to estimate the discriminant rule and the nonlabeled sample on which this rule is applied arise from the same population. In this work, we consider the case where the two populations are slightly different. In the multinormal context, we establish that both populations are linked through linear mapping. Estimation of the nonlabeled sample discriminant rule is then obtained by estimating parameters of this linear relationship. Several models describing this relationship are proposed and associated estimated parameters are given. An experimental illustration is also provided in which sex of birds that differ morphometrically over their geographical range is to be determined and a comparison with the standard allocation rule is performed. Extension to a partially labeled sample is also discussed. [source] Bedside analysis of human milk for adjustable nutrition strategyACTA PAEDIATRICA, Issue 2 2009Aiko Menjo Abstract Aim: Mother's milk is optimum for preterm infants, but human milk fortifier is required at times, because some nutrients are sometimes insufficient for infant growth. It is important to measure the nutrients in breast milk at bedside so that the amount of nutrients that need to be supplemented can be determined. A human milk analyser (HMA, Miris®) is currently available. We examined if the macronutrient values measured by human milk analyser are comparable with those measured by conventional methods. We also sought to discover whether we could dilute the milk sample used for the human milk analyser measurement if the amount of milk available for testing was insufficient. Subjects and Methods: First, the results of protein, fat and lactose content in breast milk samples obtained using the human milk analyser and conventional methods were compared. Second, we measured diluted samples and compared the values with nondiluted samples. Results: When comparing the human milk analyser and conventional methods, all three nutrients exhibited a significantly positive correlation (p < 0.001); lactose content was reliable on the condition that it is 6,7 g/dL. The lactose content measured by the HPLC method was obtained by 3.05 × human milk analyser value , 13.4. When comparing diluted and nondiluted samples, fat and protein had expected values after dilution whereas lactose did not. Conclusion: The human milk analyser can inform us about the amount of major nutrients in breast milk: fat, protein and lactose. However, when human milk is diluted, the lactose content measured by the human milk analyser is overestimated. [source] A breath test to assess compliance with disulfiramADDICTION, Issue 12 2006Keron Fletcher ABSTRACT Aims To evaluate the ability of a hand-held breath analyser, the Zenalyser® (Zenics Medical), to identify alcohol-dependent patients receiving disulfiram therapy and to assess the sensitivity and specificity of the instrument at different time intervals post-disulfiram dosing. Design Breath samples were taken from two groups of alcohol-dependent patients, one group on a daily disulfiram regimen and one group receiving no disulfiram. The breath samples were analysed for the combined concentration of carbon disulphide and acetone produced from the metabolism of disulfiram. From these data, two reference ranges were prepared and used for sensitivity and specificity assessments. Setting Breath samples for the reference ranges were obtained from patients at Shelton Hospital, Shrewsbury. Breath samples used to assess the sensitivity and specificity of the instrument were obtained from patients at the Edinburgh Alcohol Problems Clinic. Participants Twenty in-patients from Shelton Hospital receiving a daily 200 mg disulfiram regimen and 20 in-patients receiving no disulfiram. At the Edinburgh Clinic, 54 patients taking a thrice-weekly disulfiram regimen and 22 patients not on disulfiram. Measurements A total of 489 breath samples from Shelton Hospital and 391 breath samples from the Edinburgh Clinic were analysed for the combined concentrations of carbon disulphide and acetone. Findings The breath analyser produced results that distinguished between the disulfiram-treated and untreated groups (P < 0.001). At 1 day post-dose, the sensitivity was 100% and the specificity was 100%. At 2 and 3 days post-dose, the sensitivities and specificities were 84.6% and 100% and 88.2% and 100%, respectively. Conclusion The breath analyser can improve the assessment of the compliance status of patients receiving a daily dose regimen of disulfiram, but is less useful for this purpose if disulfiram is taken on a thrice-weekly regimen. [source] The reliability of emplacement temperature estimates using palaeomagnetic methods: a case study from Santorini, GreeceGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 1 2000Leon Bardot The mode of origin of volcaniclastic deposits can be difficult to determine from field constraints, and the palaeomagnetic technique of emplacement temperature (Te) determination provides a powerful discriminatory test for primary volcanic origin. This technique requires that the low-blocking-temperature (Tb) component of remanence in the direction of the Earth's field in inherited lithic clasts is of thermal origin and was acquired during transport and cooling in a hot pyroclastic flow; otherwise, the Te determination may be inaccurate. If the low- Tb component is not of thermal origin it may be a viscous remanent magnetization (VRM) or a chemical remanent magnetization (CRM). The acquisition of a VRM depends on the duration of exposure to an applied magnetic field, and thus the laboratory unblocking temperature (Tub) of a VRM of a certain age imposes a minimum Te that can be determined for that deposit. Palaeointensity experiments were carried out to assess the magnetic origin (pTRM, CRM, or a combination of both) of the low- Tb component in a number of samples from pyroclastic deposits from Santorini, Greece. Seven of the 24 samples used in these experiments passed the stringent tests for reliable palaointensity determination. These values demonstrated, for six of the samples, that the low- Tb component was of thermal origin and therefore that the estimate of Te was valid. In the other 17 samples, valuable information was gained about the characteristics of the magnetic alteration that occurred during the palaeointensity experiments, allowing assessment of the reliability of Te estimates in these cases. These cases showed that if a CRM is present it has a direction parallel to the applied field, and not parallel to the direction of the parent grain. They also show that, even if a CRM is present, it does not necessarily affect the estimate of Te. Two samples used in these experiments displayed curvature between their two components of magnetization. Data from this study indicate that the curvature in these vector plots is probably due to the presence of MD grains and not CRM, although CRM is not ruled out as the cause of curvature in other samples with two vector components. [source] Outcomes of the International Union of Crystallography Commission on Powder Diffraction Round Robin on Quantitative Phase Analysis: samples 1a to 1hJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2001Ian C. Madsen The International Union of Crystallography (IUCr) Commission on Powder Diffraction (CPD) has sponsored a round robin on the determination of quantitative phase abundance from diffraction data. Specifically, the aims of the round robin were (i) to document the methods and strategies commonly employed in quantitative phase analysis (QPA), especially those involving powder diffraction, (ii) to assess levels of accuracy, precision and lower limits of detection, (iii) to identify specific problem areas and develop practical solutions, (iv) to formulate recommended procedures for QPA using diffraction data, and (v) to create a standard set of samples for future reference. Some of the analytical issues which have been addressed include (a) the type of analysis (integrated intensities or full-profile, Rietveld or full-profile, database of observed patterns) and (b) the type of instrument used, including geometry and radiation (X-ray, neutron or synchrotron). While the samples used in the round robin covered a wide range of analytical complexity, this paper reports the results for only the sample 1 mixtures. Sample 1 is a simple three-phase system prepared with eight different compositions covering a wide range of abundance for each phase. The component phases were chosen to minimize sample-related problems, such as the degree of crystallinity, preferred orientation and microabsorption. However, these were still issues that needed to be addressed by the analysts. The results returned indicate a great deal of variation in the ability of the participating laboratories to perform QPA of this simple three-component system. These differences result from such problems as (i) use of unsuitable reference intensity ratios, (ii) errors in whole-pattern refinement software operation and in interpretation of results, (iii) operator errors in the use of the Rietveld method, often arising from a lack of crystallographic understanding, and (iv) application of excessive microabsorption correction. Another major area for concern is the calculation of errors in phase abundance determination, with wide variations in reported values between participants. Few details of methodology used to derive these errors were supplied and many participants provided no measure of error at all. [source] Application of chitosan solutions gelled by melB tyrosinase to water-resistant adhesivesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2008Kazunori Yamada Abstract An investigation was undertaken on the application of dilute chitosan solutions gelled by melB tyrosinase-catalyzed reaction with 3,4-dihydroxyphenethylamine (dopamine). The tyrosinase-catalyzed reaction with dopamine conferred water-resistant adhesive properties to the semi-dilute chitosan solutions. The viscosity of the chitosan solutions highly increased by the tyrosinase-catalyzed quinone conversion and the subsequent nonenzymatic reactions of o -quinones with amino groups of the chitosan chains. The viscosity of chitosan solutions highly increased in shorter reaction times by addition of melB tyrosinase. Therefore, in this study, the gelation of a chitosan solution was carried out without poly(ethylene glycol) (PEG), which was added for the gelation of chitosan solutions using mushroom tyrosinase. The highly viscous, gel-like modified chitosan materials were allowed to spread onto the surfaces of the glass slides, which were tightly lapped together and were held under water. Tensile shear adhesive strength of over 400 kPa was observed for the modified chitosan samples. An increase in either amino group concentration of the chitosan solutions or molecular mass of the chitosan samples used effectively led to an increase in adhesive strength of the glass slides. Adhesive strength obtained by chitosan materials gelled enzymatically was higher than that obtained by a chitosan gel prepared with glutaraldehyde as a chemical crosslinking agent. In addition, the use of melB tyrosinase led to a sharp increase in adhesive strength in shorter reaction times without other additives such as PEG. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Accuracy of the Calibration Curve Method for Absorbed Dose Assessment in Irradiated Refrigerated Chicken BoneJOURNAL OF FOOD SCIENCE, Issue 1 2001A.A. Basfar ABSTRACT: The influence of the decay of the radiation induced free radicals on electron spin resonance (ESR) bone dosimetry was studied. The absorbed doses in irradiated bone are usually assessed by applying correction factors for decay. An alternative procedure is presented in which the ESR readout was performed only when the ESR signal had reached good stability for the bone samples used to establish the calibration curves and also on bones for which absorbed dose assessment was to be made. The results of the evaluated doses obtained by using this approach were the same as the ones obtained by using corrections for the decay of ESR signals. [source] Soft-sensor development using correlation-based just-in-time modelingAICHE JOURNAL, Issue 7 2009Koichi Fujiwara Abstract Soft-sensors have been widely used for estimating product quality or other key variables, but their estimation performance deteriorate when the process characteristics change. To cope with such changes, recursive PLS and Just-In-Time (JIT) modeling have been developed. However, recursive PLS does not always function well when process characteristics change abruptly and JIT modeling does not always achieve the high-estimation performance. In the present work, a new method for constructing soft-sensors based on a JIT modeling technique is proposed. In the proposed method, referred to as correlation-based JIT modeling (CoJIT), the samples used for local modeling are selected on the basis of the correlation among measured variables and the model can adapt to changes in process characteristics. The usefulness of the proposed method is demonstrated through a case study of a CSTR process, in which catalyst deactivation and recovery are taken into account. In addition, its industrial application to a cracked gasoline fractionator is reported. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] XAFS analysis of corroded metal surfaces with molten salts by conversion-electron-yield methodJOURNAL OF SYNCHROTRON RADIATION, Issue 2 2001Etsuya Yanase We have measured XAFS spectra of metal surfaces corroded with melting salt (NaCl, KCl, and Na2SO4). Steel samples used were S45C, SCM435, SUS310S, and SUS304. We measured the Fe K-edge XAFS spectra for all samples and the Ni K-edge for SUS310S and SUS304 samples before and after the corrosion. The XANES spectra of samples before the corrosion show metallic structure because surface oxide thickness is thinner than probing depth with a conversion yield XAFS method. Each result of these XAFS spectra gives good agreements with the FEFF calculation in the assumption of bcc and/or fcc structure. The Fe K-edge spectra of steel samples except SUS310S after corroded treatment show existence bonding between Fe and another light element although the spectra of SUS310S samples before and after corroded treatment are much the same. Keywords: metal, molten salts, corrosion. [source] Measuring Mental Health Following Traumatization: Psychometric Analysis of the Kuwait Raha Scale Using a Random National Household Data SetAMERICAN JOURNAL OF ORTHOPSYCHIATRY, Issue 2 2009Paula Chapman PhD The authors report on the psychometric properties of the Kuwait Raha Scale (KRS), a measure developed to assess well-being among Kuwaitis. Specific aims of the study were to (a) evaluate competing models of the latent structure of the KRS using exploratory factor analysis and identify the best model, (b) compare the model developed from a nationally representative sample with the initial model reported with Kuwaiti undergraduate students, and (c) assess the discriminant validity of the KRS with the General Health Questionnaire (GHQ). Factor analysis suggested that a 5-factor model best suited the data, whereas the development of the KRS indicated a 4-factor model. Differences in the latent structure found between the current study and the original examination of the KRS factor structure may be attributed to the demographics of the samples used in the 2 studies. Whereas the earlier study used a sample of undergraduate college students, the current study acquired a nationally representative sample of the Kuwaiti population. Discriminant validity of the KRS with the GHQ indicated that the KRS and the GHQ measure different dimensions of health. Implications for theory and research are discussed, with particular attention to overcoming the challenges confronting the meaning and measurement of well-being in developing countries and stimulating interdisciplinary research. [source] Optimal Two-Stage Design for Case-Control Association Analysis Incorporating Genotyping ErrorsANNALS OF HUMAN GENETICS, Issue 3 2008Y. Zuo Summary Two-stage design is a cost effective approach for identifying disease genes in genetic studies and it has received much attention recently. In general, there are two types of two-stage designs that differ on the methods and samples used to measure allele frequencies in the first stage: (1) Individual genotyping is used in the first stage; (2) DNA pooling is used in the first stage. In this paper, we focus on the latter. Zuo et al. (2006) investigated statistical power of such a design, among other things, but the cost of the study was not taken into account. The purpose of this paper is to study the optimal design under the given overall cost. We investigate how to allocate the resources to the two stages. Note that in addition to the measurement errors associated with DNA pooling, genotyping errors are also unavoidable with individual genotyping. Therefore, we discuss the optimal design combining genotyping errors associated with individual genotyping. The joint statistical distributions of test statistics in the first and second stages are derived. For a fixed cost, our results show that the optimal design requires no additional samples in the second stage but only that the samples in the first stage be re-used. When the second stage uses an entirely independent sample, however, the optimal design under a given cost depends on the population allele frequency and allele frequency difference between the case and control groups. For the current genotyping costs, we can roughly allocate 1/3 to 1/2 of the total sample size to the first stage for screening. [source] The interdependence of wavelength, redundancy and dose in sulfur SAD experimentsACTA CRYSTALLOGRAPHICA SECTION D, Issue 12 2008Michele Cianci In the last decade, the popularity of sulfur SAD anomalous dispersion experiments has spread rapidly among synchrotron users as a quick and streamlined way of solving the phase problem in macromolecular crystallography. On beamline 10 at SRS (Daresbury Laboratory, UK), a versatile design has allowed test data sets to be collected at six wavelengths between 0.979 and 2.290,Ĺ in order to evaluate the importance and the interdependence of experimental variables such as the Bijvoet ratio, wavelength, resolution limit, data redundancy and absorbed X-ray dose in the sample per data set. All the samples used in the experiments were high-quality hen egg-white lysozyme crystals. X-radiation damage was found to affect disulfide bridges after the crystals had been given a total dose of 0.20 × 107,Gy. However, with such a total dose, it was still possible in all cases to find a strategy to collect data sets to determine the sulfur substructure and produce good-quality phases by choosing an optimum combination of wavelength, exposure time and redundancy. A ,|,ano|/,(,ano), greater than 1.5 for all resolution shells was a necessary requirement for successful sulfur SAD substructure location. Provided this is achieved, it seems possible to find an optimum compromise between wavelength, redundancy and dose to provide phasing information. The choice of the wavelength should then follow the sample composition and the diffracting properties of the crystal. For strongly diffracting crystals, wavelengths equal or shorter than 1.540,Ĺ can be selected to capture the available data (provided the Bijvoet ratio is reasonable), while a longer wavelength, to gain as high a Bijvoet ratio as possible, must be used for more weakly diffracting crystals. These results suggest that an approach to a sulfur SAD experiment based on a complete description of the crystal system and the instrument for data collection is useful. [source] Differential impacts of habitat heterogeneity on male and female connectivity in a spatially structured pest systemAUSTRAL ECOLOGY, Issue 1 2009G. S. HAMILTON Abstract In a previous study, a model of landscape heterogeneity was developed and applied to a spatially structured wild rabbit (Oryctolagus cuniculus) population. That study showed clearly the influence of resource heterogeneity on connectivity levels. The simulation study was based on female movements and used population genetic validation data appropriate for a female study. Most models assume that males and females will exhibit similar patterns, although this has rarely been tested. In the current study we extend the analysis to consider differences between female and male connectivity in the same spatially structured pest system. Amplified fragment length polymorphism (AFLP) markers were screened on the same samples used previously for mtDNA analysis. The mtDNA data were used to validate female results, and AFLP data were used to validate combined male and female results. Connectivity patterns from the two simulations (female, and combined male and female) connectivity patterns showed no association. However, each was concordant with appropriate validation data, showing highly significant associations between pairwise population connectivity and the genetic data. A relative connectivity metric for the combined simulation was regressed against the mean of pairwise ,ST values, with almost 70% of the variation explained by a linear model. Demonstrating differential effects of habitat heterogeneity on male and female connectivity provides further evidence that spatial resource heterogeneity impacts on connectivity. Understanding differences in population connectivity will allow improved predictions of disease spread, local extinctions and recolonizations. Furthermore, modelling such differences in pest systems will allow management plans to be better targeted, for example by strategically introducing diseases for control purposes into populations which exhibit high male connectivity to aid spread, but low female connectivity to inhibit recolonization potential after control. [source] | |||||||||||||||||||||||||||||||