Individual variation

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Tree phyllosphere bacterial communities: exploring the magnitude of intra- and inter-individual variation among host species

Tree phyllosphere bacterial communities: exploring the magnitude of intra- and inter-individual variation among host species

We performed analyses with the ape (Paradis et al., 2004), picante (Kembel et al., 2010), and vegan (Oksanen et al., 2007) packages in R (R Development Core Team, 2013) and ggplot2 (Wickham, 2009) for data visualization. We quantified the taxonomic variation in bacterial community structure among samples with the Bray–Curtis dissimilarity. To illustrate patterns of bacterial community structure, we performed a nonmetric multidimensional scaling (NMDS) ordination of Bray–Curtis dissimilarity. We identified relationships between bacterial community structure, host species identity, and sample canopy location by conducting a permutational multivariate analysis of variance (PERMANOVA, Anderson, 2001) on the community matrix. We employed a blocking randomization to account for the non-independence of observations among sites. To decompose the total variation in the community matrix explained by host species identity and canopy location, we performed a partial redundancy analysis (RDA; Legendre & Legendre, 1998). This technique measures the amount of variation that can be attributed exclusively to each set of explanatory variables. We performed three permutational tests of multivariate homogeneity of group dispersions (Levene’s test for variances’ homogeneity multivariate equivalent; Anderson, 2006; Anderson, Ellingsen & McArdle, 2006): one to test if variance in intra-individual canopy bacterial communities was equal between individuals (30 samples from five trees sampled at six canopy locations); a second to compare interspecific variation between species (30 bottom-canopy samples from 30 different trees); and finally a third to test per-species intra- and inter-individual variation (all 55 samples). We estimated phyllosphere bacterial alpha-diversity using the Shannon index calculated from OTU relative abundances for each community. We performed an analysis of variance (ANOVA) and subsequent post-hoc Tukey’s tests to compare differences in diversity across species. The authors declare that the experiment comply with the current laws of the country in which the experiment was performed.
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Determining individual variation in growth and its implication for life-history and population processes using the empirical Bayes method.

Determining individual variation in growth and its implication for life-history and population processes using the empirical Bayes method.

The Empirical Bayes approach applied to the estimation of a parameter-rich non-linear growth function including individ- ual random effects provides a computationally efficient methodology to estimate shared and individual variation in growth. Other methods and routines can be applied to the estimation of random-effects non-linear models of growth, for instance the nlme function in R or BUGS/JAGS. However, as we report in text S2 and in the online code, when dealing with a large number of random effects, missing data, or ‘‘noisy’’ growth of individuals, some of those methods may take a very long time to converge or fail to converge. By providing a general template for fitting growth curves (i.e. not limited to the von Bertalanffy growth function) with ADMB-RE, our goal is to encourage and help researchers using more sophisticated tools to obtain fast and reliable parameter estimates of non- linear random-effects growth models using longitudinal or back-calculated data.
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Functional brain network modularity captures inter- and intra-individual variation in working memory capacity.

Functional brain network modularity captures inter- and intra-individual variation in working memory capacity.

Individual modularity values ranged over 0.21–0.49, while the within-subject changes in modularity ranged from 0.01–0.14. Thus, modularity within individuals tended to be relatively stable compared to the differences between individuals. Visual short- term memory capacity was comparable across Session 1 (mean = 3.09) and Session 2 (mean = 2.89): paired t(16) = 0.834, p = 0.34. Individual’s network modularity and VSTM capacity were positively correlated at both Session 1 (r(20) = 0.56, p = 0.009) (Fig. 2a), and Session 2 (r(15) = 0.57, p = 0.008), indicating that working memory capacity indeed varies reliably with network modularity. (When only the 17 participants who completed both Sessions 1 and 2 were included in the analysis, the correlation between network modularity and VSTM at Session 1was comparable: r(15) = 0.54, p = 0.013). Strikingly, within- individual changes in VSTM capacity between Session 1 and Session 2 also correlated with the change in their network modularity between the two sessions (r(15) = 0.54, p = 0.013). Thus, network modularity not only captured significant variability in individual differences in working memory capacity, but also tracked the within-individual changes in memory between sessions. Importantly, another measure of global network organi- zation, small-worldness (Fig. 3), yielded similar correlations with VSTM capacity at both Session 1 (r (20) = 0.50, p = 0.042) and Session 2 (r(15) = 0.59, p = 0.013). However, unlike modularity, between-session changes in small-worldness were only weakly associated with changes in VSTM capacity (r(15) = 0.35, p = 0.17) (Fig. 3). Thus, like modularity, small-worldness is sensitive to individual differences in VSTM capacity; however, unlike modularity, it is relatively insensitive to intra-individual variability in capacity.
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Individual variation is the key to the development of a vaccine against Staphylococcus aureus: a comparative study between mice lineages

Individual variation is the key to the development of a vaccine against Staphylococcus aureus: a comparative study between mice lineages

Little is known about the mechanisms of a protective immunity against an infection by S. aureus. Some authors believe that the activation of T and B cells by immunization is sufficient to generate a full protection. The inflammatory response is a complex event, with variations that depend on the intrinsic and extrinsic conditions of each individual and of the infectious agent. The variation among humans may be caused by differences among individual charac- teristics, such as hormonal levels, associated comorbid- ities, among others. S. aureus colonization and invasive disease are not associated with the development of pro- tective immune responses, which is attributable to a large spectrum of immune evasion factors (3,4).
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Fluctuating Asymmetry and Individual Variation in Regional Gray and White Matter Volumes: A Voxel-Based Morphometry Study

Fluctuating Asymmetry and Individual Variation in Regional Gray and White Matter Volumes: A Voxel-Based Morphometry Study

As mentioned above, FA has been previously linked with a variety of behavioral traits in humans. Unfortunately, in this study we were not able to evaluate potential relationships between anatomic variations and behavioral traits. The identified sites are involved in distributed neural circuits underlying a diverse set of functions; moreover, they likely comprise only one component of the total set of brain variables linked with FA, such as atypical laterality (Yeo et al., 1997) and variation in neurometabolite concentrations (Yeo, Hill, Campbell, Vigil, and Brooks, 2000). Nonetheless, the identified regions represent possible substrates for FA-related behavioral variation. For example, one site prominently linked with FA in our VBM analysis was the right dorsolateral frontal region. Zaatari and Trivers (2007) reported that low FA individuals are less likely to make “fair” offers in the ultimatum game. Right frontal fMRI activation occurs during performance of this game (Sanfey, Rilling, Aronson, Nystrom, and Cohen, 2003) and transcranial magnetic stimulation of this same region, creating a “temporary lesion,” specifically diminished behaviors reflecting reciprocal fairness (Knoch, Pascual-Leone, Meyer, Treyer, and Fehr, 2006). Hence, gray and white matter variation in the right dorsolateral frontal region may be related to behavioral variation linked with FA in the ultimatum game.
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Plasticity of coping styles in farmed fish:  behavioural and neuro-endocrine profiling

Plasticity of coping styles in farmed fish: behavioural and neuro-endocrine profiling

In addition, no relationship was found between escape behaviour and plasma cortisol levels. Several studies have documented the lack of correlation between plasma cortisol levels obtained after stress and behavioural responses (Silva et al. 2010; van Erp-van der Kooij et al. 2003; van de Nieuwegiessen et al. 2008). Some authors have suggested that cortisol and behavioural responses to stressors are linked to two independent dimensions of stable trait characteristics (Koolhaas et al. 2010). These authors suggested that the quality of the response to a challenging condition (coping style) is independent from the quantity of that response (stress reactivity). According to the same authors, the physiological responses to stress such as the HPI axis reactivity (one of the most significant differences between proactive and reactive individuals) is more related to an emotional response to stress than to coping styles. Eventually a decoupling of these axis, coping styles and emotional, could bring new light to understand the pronounced individual variation in plasma cortisol response observed in seabream after stress. However, in this study we observed a significant increase in the magnitude of the cortisol response, more than fourfold, from juveniles to adults. This difference maybe related with the developmental stage of the fish that can affect its responsiveness to a stressor (Barton 2002). However our results are in contrast with previous studies such as Pottinger et al. (1995) who found a reduction of stress response in adult rainbow trout as a result of a reduced regulatory feedback with the onset of maturity. The possible influence of age on the stress responsiveness in seabream remains to be investigated. Such discrepancy of results may be due to species- specific behaviour and/or age influence.
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Intrapopulation recurrent selection by mixed models in papaya of the Formosa group

Intrapopulation recurrent selection by mixed models in papaya of the Formosa group

A bstract – Few cultivars of papaya from the Formosa group are available to producers, and the development of new genotypes is indispensable. Thus, the use of effective selection strategies to obtain more productive cultivars and better quality fruits is also necessary. The aim of this study was to select of half-sib families (HSF) of papaya using the methodology of mixed models. Nineteen HSFs from the Incaper’s papaya breeding program were evaluated in a randomized block design with five replicates and nine plants per plot. The selection was made based on fruit mass (FM), pulp thickness (PT), soluble solids content in pulp (SS) and number of fruits (NF). The genetic parameters and genotypic values were estimated by the REML/BLUP procedure. The selected HSFs increased FM by 26.1%; the PT in 10.5%; the SS in 7.5% and; the NF in 13.0%. The additive heritability within the progenies and the individual variation coefficient obtained indicate that the selection between and within the HSFs can provide greater genetic gains. The selection based on the REML/BLUP methodology was efficient to obtain simultaneous genetic gains for all variables under study despite the negative correlation between them.
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The population growth consequences of variation in individual heterozygosity.

The population growth consequences of variation in individual heterozygosity.

The components of the population where we find heterozygosity (defined by normalised HL) most strongly influences individual contributions to population growth are prime-aged females, male lambs, and adult males (composed of prime-aged and senescents). Of these, normalised HL accounts for approximately twice as much within male contributions to population growth as in females, specifically via adult reproductive success. Despite the relative importance of normalised HL in adult males, this effect does not leave a large signature on the population dynamics because it constitutes such a small fraction of the population. Heterozygosity in males determines which males successfully mate (in some years) even if this has no effect on the number of females that would become pregnant in the absence of heterozygous males. The importance of heterozygosity in reproductive success may differ between years on account of fluctuating selection, counter- vailing selection for different fitness components or frequency- dependent selection [19,27]. Within females, normalised HL contributed little to population growth and typically much less than other measures of individual variation, such as body weight and FEC. As with all individual traits, when all females are considered together, normalised HL only contributes to survival. When each female age-class is considered separately, we find that this effect is experienced solely via prime-aged females.
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Daily oxygen consumption rhythms of Senegalese sole solea senegalensis (Kaup, 1858) juveniles

Daily oxygen consumption rhythms of Senegalese sole solea senegalensis (Kaup, 1858) juveniles

The Senegalese sole, is a common fish in the Western Mediterranean and in the Southeast coast of the Atlantic. This species is considered a nocturnal species, since in laboratorial conditions they showed a higher activity and plasma melatonin during the night (Bayarri et al., 2004). Although it is well known that oxygen consumption follows a light –dark rhythm (De la Gándara et al., 2002), the in fluence of feeding on this rhythm is not yet available in Senegalese sole, or in any flatfish. Such information may be useful to understand the oxygen requirements for this species, and for advising better feeding strategies. Furthermore, the extent of individual variation in metabolism under light and dark regimes has never been reported. A full understanding of the light –dark rhythm provides basic knowledge on variability of oxygen responses and these effects may be considered when interpreting respirometry studies on stress or nutritional effects.
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The influence of coastal access on isotope variation in Icelandic arctic foxes.

The influence of coastal access on isotope variation in Icelandic arctic foxes.

To quantify the ecological effects of predator populations, it is important to evaluate how population-level specializations are dictated by intra- versus inter-individual dietary variation. Coastal habitats contain prey from the terrestrial biome, the marine biome and prey confined to the coastal region. Such habitats have therefore been suggested to better support predator populations compared to habitats without coastal access. We used stable isotope data on a small generalist predator, the arctic fox, to infer dietary strategies between adult and juvenile individuals with and without coastal access on Iceland. Our results suggest that foxes in coastal habitats exhibited a broader isotope niche breadth compared to foxes in inland habitats. This broader niche was related to a greater diversity of individual strategies rather than to a uniform increase in individual niche breadth or by individuals retaining their specialization but increasing their niche differentiation. Juveniles in coastal habitats exhibited a narrower isotope niche breadth compared to both adults and juveniles in inland habitats, and juveniles in inland habitats inhabited a lower proportion of their total isotope niche compared to adults and juveniles from coastal habitats. Juveniles in both habitats exhibited lower intra-individual variation compared to adults. Based on these results, we suggest that foxes in both habitats were highly selective with respect to the resources they used to feed offspring, but that foxes in coastal habitats preferentially utilized marine resources for this purpose. We stress that coastal habitats should be regarded as high priority areas for conservation of generalist predators as they appear to offer a wide variety of dietary options that allow for greater flexibility in dietary strategies.
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Individual, spatial and inter-sex variation in somatic growth: a study of Piaractus mesopotamicus (Characiformes: Serrasalmidae), a long-distance freshwater Neotropical migratory fish

Individual, spatial and inter-sex variation in somatic growth: a study of Piaractus mesopotamicus (Characiformes: Serrasalmidae), a long-distance freshwater Neotropical migratory fish

A robust growth model must take into account individual variation at a variety of levels, since any observed difference in somatic growth in populations can result from the interaction of the genotype with exogenous factors (Weisberg et al., 2010). Each individual is born with a particular genetic make-up that to some extent controls its growth profile, but physical and biological processes modify the on-going growth rate of an individual (Shelton et al., 2013; Vincenzi et al., 2014). Traditional growth models (i.e., a single observation of length-at-age data per individual) clearly ignore such individual variability because they do not consider the growth trajectory of each individual in the population, and estimates of somatic growth parameters are usually described by “average” population parameters. Recent studies emphasize the importance of including intra- population variation in growth models so as to reduce bias in parameter estimation (Pilling et al., 2002; Dieterman et al., 2012; Shelton et al., 2013; Vincenzi et al., 2014). This is important because individuals in a population do not have similar growth parameters. The main problem in the use of models that assume the absence of individual variability is the bias in the life expectancy of the species. In the case of selective fishing size, longevity is a attribute dependent on individual body size, and those individuals that grow most rapidly tend to be captured at a younger age than those
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Cloacal Microbiome Structure in a Long-Distance Migratory Bird Assessed Using Deep 16sRNA Pyrosequencing.

Cloacal Microbiome Structure in a Long-Distance Migratory Bird Assessed Using Deep 16sRNA Pyrosequencing.

The Chao1 index [46], phylogenetic diversity index (computed as total branch length), and number of OTUs detected in individual samples were calculated to provide further information on CM alpha diversity. In addition, total OTU richness for individual samples was estimated based on best-fitting parametric model implemented in CatchAll [47]. Coverage of CM diver- sity by our sequencing data was assessed based on rarefaction analysis and Goods coverage index [48]. Paired t-tests were used to test whether alpha diversity differed between males and females. Distances between samples were visualised using non-metric multidimensional scaling (NMDS) and distance-based redundancy analysis (db-RDA), implemented in the vegan pack- age [49], was used to test whether CM composition differed systematically between males and females and between breeding colonies. The betadisper function (analogous to Levene’s test of equality of variance), was used as a next step to assess whether inter-individual variation in Hellinger and UniFrac distance differed between males and females. Finally, we applied the Wilcoxon signed rank test to detect differences in proportional composition of individual bac- terial phyla and families between males and females. The same approach was used to compare the proportion of individual OTUs (i.e. number of reads for a given OTU in a given sample divided by total number of reads for a given sample) that were represented by < 0.1% reads (number of OTUs = 123, see S2 Table for more detail). The q-value method was applied to account for false discoveries when using multiple comparisons [50] (q-value threshold was set to 0.05). In addition, corrected moment estimates of k parameter of the negative binomial dis- tribution was calculated for these OTUs. This index is widely used in parasitology to quantify the level of parasite aggregation among hosts. Low values of this index imply highly aggregated distribution, whereas high values (k > 20) indicate near-Poisson distribution of infection intensities [51].
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Unusual intra-individual karyotypical variation and evidence of cryptic species in Amazonian populations of Pristimantis (Anura, Terrarana)

Unusual intra-individual karyotypical variation and evidence of cryptic species in Amazonian populations of Pristimantis (Anura, Terrarana)

We report a cytogenetic analysis of three Pristimantis fenestratus frog populations of the Amazon region in Brazil. The specimens were sampled in Borba and Manaus, Amazonas State, and in rio Branco, Acre State. They were analyzed using giemsa, silver staining, c-banding and FISH with rDnA probes. The karyotypes of the three populations revealed 2n =฀34 chromosomes, but they differed in the number and position of Ag-nOrs and in the heterochromatin pattern as well. The nOr was located on the pairs 05 and 07 in the rio Branco specimens, pair 10 in the Manaus specimens, and pair 1 in the Borba specimens. A small c-band was detected on the telomeric region of the pair 05 in the Borba population, while in the Manaus there was a heterochromatic block adjacent to the centromere of pair 9. An unusual intra-individual variation of chromosome number was observed in metaphases of rio Branco specimens, comprising fundamental numbers of 33, 34 and 35. Additionally, interchromosome thread connections were detected between telomere – telomere, centromere – telomere and centromere – centromere regions, and among chromosomal heterochromatin-rich sites. The nOr sites were also involved in those connections. We hypothesize that this variation is due to chromosome missegregation during mitosis. The inter- and intraindividual variation in chromosome number suggests chromosomal instability in P. fenestratus, which has not been detected in any other anuran group. Since Borba is the type-locality of P. fenestratus, a taxonomic review of the Manaus and rio Branco populations should be done, as indicated by the cytogenetic evidence that they could be new species of Pristimantis.
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Dialysis water treated by reverse osmosis decreases the levels of C-reactive protein in uremic patients

Dialysis water treated by reverse osmosis decreases the levels of C-reactive protein in uremic patients

by others (33,34). It is interesting to note that CRP levels after the change of the water purification system correlated closely with the previous CRP levels, suggesting that the patients present a pattern of inflammatory activity dependent on other factors. This fact has been emphasized before, making this protein useful as a prognostic tool, even after single isolated measurements (24,25,35,36), despite a high intra-individual variation (37). In conclusion, in a natural experiment based on the change of the water purification system in a hemodialysis unit treating unse- lected patients, we demonstrated that: a) patients who eventually died had higher in- flammatory activity than the survivors; b) the survivors, without obvious clinical in- flammation, when dialyzing with another water purification system, apparently with lower levels of endotoxin, presented a sig- nificant and clinically relevant reduction of CRP levels. This occurred even though both water treatments presented acceptable levels of bacterial contamination and endotoxin. Although several causes contribute to the chronic microinflammatory state of uremic patients on dialysis, a small contamination of dialysate water with bacterial endotoxin may be an important factor to be considered, specially in developing countries, where cost restrictions may lead to the use of less efficient water purification systems.
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Selection and genetic gain in rubber tree (Hevea) populations using a mixed mating system

Selection and genetic gain in rubber tree (Hevea) populations using a mixed mating system

The accuracy and genetic gain estimates for RP var- ied within and among locations in the different selection methods. When the accuracy values associated to the ge- netic gain are greater, the expected progress with selection was also greater, i.e., the greater the precision in selection the greater the gain. The genetic gain was much more ex- pressive at Pindorama than at Votuporanga or Jaú. These results agree with those obtained by Moreti et al. (1994) for mass selection and can be explained by the high herita- bility values at the individual level at Pindorama compared to those at Votuporanga and Jaú. They also indicate that Pindorama was a more favorable environment for the ex- pression of genetic variability, as shown by the RP coeffi- cients of genetic variation (CV g %).
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Rev. adm. empres.  vol.54 número6

Rev. adm. empres. vol.54 número6

ΔROIC = return on invested capital (ROIC) variation; ΔROA = return on assets (ROA) variation; Sls Grth = percentage variation in sales; Op Cst Incr = percentage variation in operational[r]

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Rev. CEFAC  vol.18 número3

Rev. CEFAC vol.18 número3

Methods: quantitative cross-sectional study, with 13 singers, eight women and ive men, mean age of 39± 20.11 years, with different voice types. The vocal range proile was obtained using Vocalgrama software (CTS Informática). Samples were collected at three different times: before, after one minute and after two minutes of applying the sonorous tongue-trill technique associated with tonal variation. Results: six chorists (46.2%) showed an increase in vocal range proile after two minutes of the techni- que. Sopranos and tenors obtained higher mean vocal range proile at any of the three times considered. Conclusion: the sonorous tongue-trill technique associated with tonal variation had no effect on the vocal range proile of the chorists under study. However, time spent on exercises and voice types seemed to have an inluence on the results.
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Do habitus ao patrimônio individual de disposições: rumo a uma sociologia em escala individual

Do habitus ao patrimônio individual de disposições: rumo a uma sociologia em escala individual

economia das lógicas sociais individualizadas, supondo que a sociologia se interessa pelo indivíduo (não como átomo, mas como produto complexo de múltiplos processos de socialização).. N[r]

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Sex, Diet, and the Social Environment: Factors Influencing Hair Cortisol Concentration in Free-Ranging Black Bears (Ursus americanus).

Sex, Diet, and the Social Environment: Factors Influencing Hair Cortisol Concentration in Free-Ranging Black Bears (Ursus americanus).

regards to ursids, the temporal relationship between serum total cortisol concentration and HCC is ambiguous [19], thereby complicating interpretations about the biological relevance and temporal frame over which HCC represents [2]. Hair collected from different parts of the body also may have different cortisol concentrations [19]. Because we used samples obtained through noninvasive methods [25, 26], we acknowledge that hair samples used in our study likely came from several different parts of the body, which may have affected our results; although we observed little differences among individuals of the same sex. Despite these chal- lenges, mounting evidence suggests that as a retrospective biomarker of endocrine activity in wildlife, including assessments from four species of bears [13, 16, 17, 19, 42, 48, 57, 58], mea- sures of HCC may provide meaningful insight into the long-term physiological responses of individuals to their environment. Greater understanding of observed HCC patterns in non- invasively sampled, free-ranging wildlife can help build our understanding of the eco-evolu- tionary significance of intrapopulation differences in HCC, which also can inform conservation and management planning. However, for HCC to be a useful tool, factors that contribute to intrapopulation variability in HCC must be identified. As such, in addition to measures of diet, sex and densities of conspecific and heterospecific competitors, future studies would benefit from incorporating measures of reproductive condition (e.g., testosterone, estradiol), identify- ing presence of young, age data and when possible, social rank. Moreover, studies that evaluate linkages between HCC and measures of fitness (e.g., survival, reproduction) in wildlife would enhance the utility of HCC as a conservation tool. Macbeth et al. [48] found preliminary evi- dence that HCC in polar bears (U. maritimus) was inversely related to measures of growth (i.e., length, mass, body condition index [BCI; [59]] and previous research provides evidence of a direct relationship between growth and fitness in polar bears [60 – 62]. However, few studies have linked HCC in mammals to measures of fitness. Once we understand the drivers of intra- population differences in HCC and how HCC is related to measures of fitness, HCC will have tremendous potential to inform our understanding of the physiological stress burden experi- enced by wildlife due to diverse environmental challenges and inform our understanding of the eco-evolutionary consequences of that stress burden to individual and population-level well- being.
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Higiene publica e individual

Higiene publica e individual

El carbunco humano es una de las enfermedades más propagadas en la Argentina, donde alcanza proporciones no igualadas ni en el Brasil, ni otros países sudamerican[r]

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