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1.
ABSTRACT Telemetry data have been widely used to quantify wildlife habitat relationships despite the fact that these data are inherently imprecise. All telemetry data have positional error, and failure to account for that error can lead to incorrect predictions of wildlife resource use. Several techniques have been used to account for positional error in wildlife studies. These techniques have been described in the literature, but their ability to accurately characterize wildlife resource use has never been tested. We evaluated the performance of techniques commonly used for incorporating telemetry error into studies of wildlife resource use. Our evaluation was based on imprecise telemetry data (mean telemetry error = 174 m, SD = 130 m) typical of field-based studies. We tested 5 techniques in 10 virtual environments and in one real-world environment for categorical (i.e., habitat types) and continuous (i.e., distances or elevations) rasters. Technique accuracy varied by patch size for the categorical rasters, with higher accuracy as patch size increased. At the smallest patch size (1 ha), the technique that ignores error performed best on categorical data (0.31 and 0.30 accuracy for virtual and real data, respectively); however, as patch size increased the bivariate-weighted technique performed better (0.56 accuracy at patch sizes >31 ha) and achieved complete accuracy (i.e., 1.00 accuracy) at smaller patch sizes (472 ha and 1,522 ha for virtual and real data, respectively) than any other technique. We quantified the accuracy of the continuous covariates using the mean absolute difference (MAD) in covariate value between true and estimated locations. We found that average MAD varied between 104 m (ignore telemetry error) and 140 m (rescale the covariate data) for our continuous covariate surfaces across virtual and real data sets. Techniques that rescale continuous covariate data or use a zonal mean on values within a telemetry error polygon were significantly less accurate than other techniques. Although the technique that ignored telemetry error performed best on categorical rasters with smaller average patch sizes (i.e., ≤31 ha) and on continuous rasters in our study, accuracy was so low that the utility of using point-based approaches for quantifying resource use is questionable when telemetry data are imprecise, particularly for small-patch habitat relationships.  相似文献   

2.

Background

Research conducted in high-income countries has investigated influences of socioeconomic inequalities on drinking outcomes such as alcohol use disorders (AUD), however, associations between area-level neighborhood social deprivation (NSD) and individual socioeconomic status with these outcomes have not been explored in Brazil. Thus, we investigated the role of these factors on drink-related outcomes in a Brazilian population, attending to male-female variations.

Methods

A multi-stage area probability sample of adult household residents in the São Paulo Metropolitan Area was assessed using the WHO Composite International Diagnostic Interview (WMH-CIDI) (n = 5,037). Estimation focused on prevalence and correlates of past-year alcohol disturbances [heavy drinking of lower frequency (HDLF), heavy drinking of higher frequency (HDHF), abuse, dependence, and DMS-5 AUD] among regular users (RU); odds ratio (OR) were obtained.

Results

Higher NSD, measured as an area-level variable with individual level variables held constant, showed an excess odds for most alcohol disturbances analyzed. Prevalence estimates for HDLF and HDHF among RU were 9% and 20%, respectively, with excess odds in higher NSD areas; schooling (inverse association) and low income were associated with male HDLF. The only individual-level association with female HDLF involved employment status. Prevalence estimates for abuse, dependence, and DSM-5 AUD among RU were 8%, 4%, and 8%, respectively, with excess odds of: dependence in higher NSD areas for males; abuse and AUD for females. Among RU, AUD was associated with unemployment, and low education with dependence and AUD.

Conclusions

Regular alcohol users with alcohol-related disturbances are more likely to be found where area-level neighborhood characteristics reflect social disadvantage. Although we cannot draw inferences about causal influence, the associations are strong enough to warrant future longitudinal alcohol studies to explore causal mechanisms related to the heterogeneous patterns of association and male-female variations observed herein. Hopefully, these findings may help guide future directions for public health.  相似文献   

3.
Cells of higher organisms can commit suicide in response to genomic alterations, a process called programmed cell death. Although it is commonly thought that the loss of programmed cell death is required for carcinogenesis, we argue that the situation is more complex and that the loss of programmed cell death can have the converse effect, preventing cancer progression. If the death rate of cancer cells is low, fewer cell divisions are required for the tumor to reach a certain size, resulting in the presence of fewer mutant cells. Therefore, the chances of overcoming potential selective barriers are reduced, rendering the failure of pathogenic progression probable. However, if there is a higher cell death rate, more cell divisions need to occur for the tumor to reach a certain size, resulting in the presence of more mutant cells and in an increased probability of overcoming selective barriers and cancer progression.  相似文献   

4.
5.
When analyzing the metabolism of our economy, the usual choice for a measure of resource consumption is the throughput of matter and energy. This, however, cannot be sufficient, since consumption by definition is always relating to the destruction or transformation, and hence a change in quality, not only in quantity, of material or energy flows. Here, an approach is presented that takes the entropy production associated with any process as a measure for the resource consumption of that process. Entropy production is thereby used to approximate the intuitive notion of consumption, which can best be described by the term loss of potential utility. This article delivers theoretical evidence for the validity of this choice, and a second article in a future issue will present an application taken from the metallurgical sector. The related concept of exergy analysis is discussed and compared against the entropy approach.  相似文献   

6.
In the first part of this series of two articles, an approach was presented that takes the entropy production associated with any process as a measure of the resource consumption of that process. Entropy production is thereby used to approximate the intuitive notion of consumption, which can best be described by the term “loss of potential utility.” This article presents an application example from the metallurgical sector. The related concept of exergy analysis is discussed and compared against the entropy approach. It was found that the production of 1 ton of refined copper generates 90.2 megajoules per Kelvin of entropy. A comparison with exergy analyses of copper production processes from the literature shows agreement at least on the order of magnitude. While results in one case deviate from the entropy analysis by about 40%, in another case the deviation is about 160%. One can only speculate on the reasons for this discrepancy, without knowing the exact process specifications of the processes analyzed. For entropy production as a measure for resource consumption, a baseline for comparison and interpretation of the results based on natural entropy disposal and reduction mechanisms is suggested.  相似文献   

7.
Planthoppers and leafhoppers are important rice pests. We tried to find out whether a polyculture of silver barb, common carp and Nile tilapia could control hoppers in intensively cropped rice fields. We used the data of five rice-fish experiments conducted between 1995 and 1998 at the Co Do rice-fish research station, Can Tho province, Mekong Delta, Vietnam. Our results showed that the number of Nilaparvata lugens (Stål), Sogatella furcifera (Horváth), Nephotettix virescens (Distant) and Recilia dorsalis (Motschulsky) was the same in fields with and without stocked fish. We concluded that the three stocked fish species are not able to control hopper numbers. Other, predatory fish species might be more effective in hopper control.  相似文献   

8.
Abundant evidence across the behavioral and social sciences suggests that there are substantial individual differences in pro-social behavior. However, little is known about the psychological mechanisms that underlie social preferences. This paper investigates whether empathy and Theory of Mind shape individual differences in pro-social behavior as conventionally observed in neutrally framed social science experiments. Our results show that individual differences in the capacity for empathy do not shape social preferences. The results qualify the role of Theory of Mind in strategic interaction. We do not only show that fair individuals exhibit more accurate beliefs about the behavior of others but that Theory of Mind can be effectively used to pursue both self-interest and pro-social goals depending on the principle objectives of a person.  相似文献   

9.
10.
Currently assessment and management of animal welfare are based on the supposition that welfare status is something experienced identically by each individual animal when exposed to the same conditions. However, many authors argue that individual welfare cannot be seen as an ‘objective’ state, but is based on the animal’s own self-perception; such perception might vary significantly between individuals which appear to be exposed to exactly the same challenges. We argue that this has two implications: (1) actual perceived welfare status of individuals in a population may vary over a wide range even under identical environmental conditions; (2) animals that appear to an external observer to be in better or poorer welfare condition may all in fact perceive their own individual status as the same. This would imply that optimum welfare of a social group might be achieved in situations where individual group members differ markedly in apparent welfare status and perceive their own welfare as being optimal under differing circumstances. Welfare phenotypes may also vary along a continuum between self-regarding and other-regarding behaviour; a variety of situations exist where (social) individuals appear to invest in the welfare of other individuals instead of maximising their own welfare; in such a case it is necessary to re-evaluate individual welfare within the context of a social group and recognise that there may be consequences for the welfare of individuals, of decisions made at the group level or by other group members.  相似文献   

11.
Gray mouse lemurs (Microcebus murinus) occur in western Madagascar from the evergreen littoral rain forests at the southern tip of the island to the seasonal dry deciduous forests of the west and northwest. The wide geographic distribution allows researchers to investigate whether ecogeographic variations reflect adaptations to ambient temperatures, as a proxy for constraints of thermoregulation, or to rainfall, as a proxy of food availability. We compared body mass, number of litters/yr, and longevity for 3 populations: 1 from the evergreen littoral rain forest of the south (Mandena: annual mean temperature 23°C, 1600 mm rain/yr), 1 from the dry deciduous forest of the west (Kirindy/CFPF: 25°C, 800 mm), and 1 from the dry deciduous forest of northwestern Madagascar (Ampijoroa: 27°C, 1200 mm). Body mass decreases with increasing ambient temperature from south to north (Mandena > Kirindy/CFPF > Ampijoroa). The number of litters/yr was highest in the littoral rain forest (2 or 3 litters/yr) and decreased with decreasing rainfall (Mandena > Ampijoroa > Kirindy/CFPF). Life expectancy is lowest in the littoral forest (13% recaptures of mouse lemurs between years) and high (ca. 30–40% recaptures between years) in the dry forests (Mandena < Kirindy/CFPF and Ampijoroa). We postulate that constraints of thermoregulation result in the latitudinal gradient of body mass. Reduced resource productivity or seasonality is reflected in differences in reproductive rates, which seemed to be traded off against longevity. Thus body mass, longevity, and reproductive parameters respond differently to ambient conditions.  相似文献   

12.
Protocatechuic aldehyde (PAL) has been reported to bind to DJ-1, a key protein involved in Parkinson’s disease (PD), and exerts potential neuroprotective effects via DJ-1 in SH-SY5Y cells. In this study, we investigated the neuroprotective pharmacological effects of PAL against neurotoxin-induced cell and animal models of PD. In cellular models of PD, PAL markedly increased cell viability rates, mitochondrial oxidation-reduction activity and mitochondrial membrane potential, and reduced intracellular ROS levels to prevent neurotoxicity in PC12 cells. In animal models of PD, PAL reduced the apomorphine injection, caused turning in 6-OHDA treated rats, and increased the motor coordination and stride decreases in MPTP treated mice. Meanwhile, in an MPTP mouse model, PAL prevented a decrease of the contents of dopamine (DA) and its metabolites in the striatum and TH-positive dopaminergic neuron loss in the substantia nigra (SN). In addition, PAL increased the protein expression of DJ-1 and reduced the level of α-synuclein in the SN of MPTP lesioned mice. PAL also increased the spine density in hippocampal CA1 neurons. The current study demonstrates that PAL can efficiently protect dopaminergic neurons against neurotoxin injury in vitro and in vivo, and that the potential mechanisms may be related to its effects in increasing DJ-1, decreasing α-synuclein and its growth-promoting effect on spine density.  相似文献   

13.
Native plant individuals often persist within communities dominated by exotics but the influence of this exposure on native populations is poorly understood. Selection for traits contributing to competitive ability may lead to native plant populations that are more tolerant of the presence of exotic invaders. In this way, long‐term coexistence with an exotic may confer competitive advantages to remnant (experienced) native populations and be potentially beneficial to restoration. In past studies we have documented genetic differentiation within native grass populations exposed to the exotic invader Russian knapweed (Acroptilon repens). Here, we examine populations of a cool‐season grass, needle‐and‐thread (Hesperostipa comata [Trin. & Rupr.]) and a warm season, alkali sacaton (Sporobolus airoides [Torr.]) collected from Russian knapweed‐invaded sites and adjacent noninvaded sites to assess their relative competitive ability against a novel exotic neighbor, Canada thistle (Cirsium arvense). Experienced S. airoides (from within A. repens invasions) appear to better tolerate (accumulate biomass, leaf nitrogen content, and to initiate new tillers) the presence of a novel competitor (C. arvense). Experienced and inexperienced H. comata genets differ in their response to the presence of C. arvense. Relative neighbor effects of native grasses on C. arvense were generally greater from experienced grasses. The ability to compete with novel neighbors may be driven by general competitive traits rather than species‐specific coevolutionary trajectories. Irrespective of competitive mechanisms, the conservation of native species populations within weed invasions may provide an important restoration tool by retaining unique components of native gene pools selected by competitive interactions with exotics.  相似文献   

14.
Ruiz-Mercado  Ilse  Masera  Omar 《EcoHealth》2015,12(1):42-56
EcoHealth - The implementation of clean fuel and stove programs that achieve sustained use and tangible health, environmental, and social benefits to the target populations remains a key challenge....  相似文献   

15.
The effective population size (Ne) is proportional to the loss of genetic diversity and the rate of inbreeding, and its accurate estimation is crucial for the monitoring of small populations. Here, we integrate temporal studies of the gecko Oedura reticulata, to compare genetic and demographic estimators of Ne. Because geckos have overlapping generations, our goal was to demographically estimate NbI, the inbreeding effective number of breeders and to calculate the NbI/Na ratio (Na = number of adults) for four populations. Demographically estimated NbI ranged from 1 to 65 individuals. The mean reduction in the effective number of breeders relative to census size (NbI/Na) was 0.1 to 1.1. We identified the variance in reproductive success as the most important variable contributing to reduction of this ratio. We used four methods to estimate the genetic based inbreeding effective number of breeders NbI(gen) and the variance effective populations size NeV(gen) estimates from the genotype data. Two of these methods - a temporal moment-based (MBT) and a likelihood-based approach (TM3) require at least two samples in time, while the other two were single-sample estimators - the linkage disequilibrium method with bias correction LDNe and the program ONeSAMP. The genetic based estimates were fairly similar across methods and also similar to the demographic estimates excluding those estimates, in which upper confidence interval boundaries were uninformative. For example, LDNe and ONeSAMP estimates ranged from 14–55 and 24–48 individuals, respectively. However, temporal methods suffered from a large variation in confidence intervals and concerns about the prior information. We conclude that the single-sample estimators are an acceptable short-cut to estimate NbI for species such as geckos and will be of great importance for the monitoring of species in fragmented landscapes.  相似文献   

16.
Differences in host behavior and resistance to disease can influence the outcome of host-pathogen interactions. We capitalized on the variation in aggregation behavior of Fowler''s toads (Anaxyrus [ = Bufo] fowleri) and grey treefrogs (Hyla versicolor) tadpoles and tested for differences in transmission of Batrachochytrium dendrobatidis (Bd) and host-specific fitness consequences (i.e., life history traits that imply fitness) of infection in single-species amphibian mesocosms. On average, A. fowleri mesocosms supported higher Bd prevalences and infection intensities relative to H. versicolor mesocosms. Higher Bd prevalence in A. fowleri mesocosms may result, in part, from higher intraspecific transmission due to the aggregation of tadpoles raised in Bd treatments. We also found that, independent of species, tadpoles raised in the presence of Bd were smaller and less developed than tadpoles raised in disease-free conditions. Our results indicate that aggregation behavior might increase Bd prevalence and that A. fowleri tadpoles carry heavier infections relative to H. versicolor tadpoles. However, our results demonstrate that Bd appears to negatively impact larval growth and developmental rates of A. fowleri and H. versicolor similarly, even in the absence of high Bd prevalence.  相似文献   

17.
18.
Medicinal plants continue to play an important role in healthcare, both in Mexico and around the world. We investigated the relationship between various sociodemographic factors, such as age, economic activity, years of schooling, socioeconomic levels, gender, and language proficiency, and the knowledge and frequency of medicinal plant use in Santiago Camotlán, Sierra Norte of Oaxaca, with a mainly Zapotec population. In a first stage, we interviewed specialists in depth and collected and identified plants for a catalogue of the medicinal plant flora (90 species). With this catalogue, we then interviewed a sample of the general population and the specialists on knowledge and frequency of use. The relationship between the sociodemographic variables and knowledge was analyzed by multiple regression. To explore differences of knowledge within the population, we identified three groups with a two-step cluster analysis; the results were compared statistically with a Kruskal-Wallis non-parametric test and then a post hoc Dunn’s test to see if all the differences between groups were significant. Age and occupation explained 54% of the variation of knowledge. Medicinal plant knowledge in the region persists mainly because of the necessity to treat the diseases that the “doctor does not cure,” the culture-bound syndromes, and the most common ailments, malfunctions of the digestive system.  相似文献   

19.
20.

Objective

Lack of social support is a strong predictor for poor mental health after disasters. Psychosocial post-disaster interventions may benefit from targeting survivors at risk of low support, yet it is unknown whether demographic and disaster exposure characteristics are associated with social support. This study assessed if age, gender, educational status, cohabitation, and disaster exposure severity predicted aspects of informal social support in a cohort of Swedish survivors from the 2004 Southeast Asian tsunami.

Methods

The participants were 3,536 disaster survivors who responded to a mail survey 14 months after the disaster (49% response rate). Their perceptions of present emotional support, contact with others, tangible support, negative support and overall satisfaction with informal support were assessed with the Crisis Support Scale and analysed in five separate ordinal regressions.

Results

Demographic factors and exposure severity explained variation in social supports although the effect size and predictive efficiency were modest. Cohabitation and female gender were associated with both more positive and more negative support. Single-household men were at risk for low emotional support and younger women were more likely to perceive negative support. Higher education was associated with more positive support, whereas no clear pattern was found regarding age as a predictor. Disaster exposure severity was associated with more negative support and less overall support satisfaction.

Conclusions

After a disaster that entailed little disruptions to the community the associations between demographic characteristics and social support concur with findings in the general population. The findings suggest that psychosocial disaster interventions may benefit from targeting specific groups of survivors.  相似文献   

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