Many species that inhabit seasonally ponded wetlands also rely on surrounding upland habitats and nearby aquatic ecosystems for resources to support life stages and to maintain viable populations. ...Understanding biological connectivity among these habitats is critical to ensure that landscapes are protected at appropriate scales to conserve species and ecosystem function. Biological connectivity occurs across a range of spatial and temporal scales. For example, at annual time scales many organisms move between seasonal wetlands and adjacent terrestrial habitats as they undergo life‐stage transitions; at generational time scales, individuals may disperse among nearby wetlands; and at multigenerational scales, there can be gene flow across large portions of a species’ range. The scale of biological connectivity may also vary among species. Larger bodied or more vagile species can connect a matrix of seasonally ponded wetlands, streams, lakes, and surrounding terrestrial habitats on a seasonal or annual basis. Measuring biological connectivity at different spatial and temporal scales remains a challenge. Here we review environmental and biological factors that drive biological connectivity, discuss implications of biological connectivity for animal populations and ecosystem processes, and provide examples illustrating the range of spatial and temporal scales across which biological connectivity occurs in seasonal wetlands.
Research Impact Statement: Seasonal wetlands are connected biologically to surrounding ecosystems through the movements of animals. This connectivity is critical to species conservation and ecosystem functioning.
Coloration can evolve in response to selection targeting colorful traits that affect survival or reproductive success. Trait covariation can complicate evolutionary dynamics when selection on ...covarying traits acts antagonistically. In prairie lizards (Sceloporus consobrinus), males exhibit blue ventral patches that are reduced in females. The development of ventral coloration corresponds with increases of circulating testosterone at sexual maturity. Previous work has illustrated that testosterone and coloration covary, such that individuals with higher testosterone have bluer patches. However, testosterone is known to increase mortality in many organisms, including Sceloporus, so selection against high testosterone can lead to indirect selection against bluer males. While previous work has suggested that patch coloration does not affect fitness, this has not yet been explicitly tested using estimates of survival and reproductive success. Here, we quantify patch coloration, apparent survival, encounter probability, and reproductive success in a wild population of male prairie lizards to assess the role of patch color variation on fitness. Specifically, we tested how patch coloration affects survival and reproductive success across 2 years. We found that none of the patch phenotypes we measured covaried with fitness, suggesting that neither natural nor sexual selection act, or act very weakly, on patch morphology. We found evidence of sexual selection on body size, such that larger males sired more offspring, likely through increased activity. However, this result was inconsistent, as it was only found in one year. Interestingly, we found that, in both years, bluer males were more likely to sire at least one offspring, suggesting some role of patch coloration in reproduction, although we cannot detect what that role may be. Overall, our study suggests that neither apparent survival nor reproductive success is strong drivers of the evolution of ventral coloration in S. consobrinus.
Male prairie lizards (Sceloporus consobrinus) have vibrant blue abdominal patches that develop in response to increasing androgens at sexual maturity. In this study, we quantified apparent survival and reproductive success in a wild population of prairie lizards to test the hypothesis that natural and sexual selection favor males that exhibit certain patch phenotypes, specifically predicting that males with patches that are more vibrant would die early, due to effects of testosterone, but sire more offspring because they are attractive to females. We found that, in one of two years, bluer males had lower survival probabilities, but did not sire more offspring in either year. Therefore, we conclude that neither contemporary natural nor sexual selection are strong drivers of the evolution of ventral coloration in prairie lizards.
Livestock constitutes a potential reservoir of meticillin-resistant Staphylococcus aureus isolates belonging to a recently derived lineage within clonal complex 398 (MRSA CC398-IIa). Since its ...discovery in the early 2000s, this lineage has become a major cause of human disease in Europe, posing a serious public health challenge in countries with intensive livestock production. To retrace the history of human colonisation and infection with MRSA CC398-IIa in Denmark, we conducted a nationwide, retrospective study of MRSA isolates collected from 1999 to 2011. Among 7,429 MRSA isolates screened, we identified 416 MRSA CC398-IIa isolates. Of these, 148 were from people with infections, including 51 from patients reporting no livestock exposure. The first cases of MRSA CC398-IIa infection in Denmark occurred in 2004. Subsequently, the incidence of MRSA CC398-IIa infection showed a linear annual increase of 66% from 2004 to 2011 (from 0.09 to 1.1 per 100,000 person-years). There were clear temporal and spatial relationships between MRSA CC398-IIa-infected patients with and without livestock exposure. These findings suggest substantial dissemination of MRSA CC398-IIa from livestock or livestock workers into the Danish community and underscore the need for strategies to control its spread both on and off the farm.
On the 20th anniversary of the Convention on Biological Diversity, a network of very large marine protected areas (the Big Ocean network) has emerged as a key strategy in the move to arrest marine ...decline and conserve some of the last remaining relatively undisturbed marine areas on the globe. Here we outline the ecological, economic and policy benefits of very large-scale MPAs and show their disproportionate value to global marine conservation targets. In particular we point out that very large-scale MPAs are a critical component of reaching the Aichi targets of protecting 10% of global marine habitats by 2020, because in addition to encompassing entire ecosystems, they will bring forward the expected date of achievement by nearly three decades (2025 as opposed to 2054). While the need for small MPAs remains critical, large MPAs will complement and enhance these conservation efforts. Big Ocean sites currently contain more than 80% of managed area in the sea, and provide our best hope for arresting the global decline in marine biodiversity.
Adiponectin, an adipocyte-specific secretory protein, is present in serum as three oligomeric complexes. Apart from its roles as an anti-diabetic and anti-atherogenic hormone, adiponectin has been ...implicated as an important regulator of cell growth and tissue remodeling. Here we show that some of these functions might be mediated by the specific interactions of adiponectin with several important growth factors. Among six different growth factors examined, adiponectin was found to bind with platelet-derived growth factor BB (PDGF-BB), basic fibroblast growth factor (FGF), and heparin-binding epidermal growth factor-like growth factor (HB EGF) with distinct affinities. The bindings of adiponectin with these growth factors are oligomerization-dependent. PDGF-BB bound to the high molecular weight (HMW) and middle molecular weight (MMW) complexes, but not to the low molecular weight (LMW) complex of adiponectin. Basic FGF preferentially interacted with the HMW form, whereas HB EGF bound to all three forms with comparable affinities. These three growth factors did not compete with each other for their bindings to adiponectin, suggesting the involvement of distinct binding sites. The interactions of adiponectin with PDGF-BB, basic FGF, and HB EGF precluded the bindings to their respective membrane receptors and attenuated the DNA synthesis and cell proliferation induced by these growth factors. Small interfering RNA-mediated down-regulation of adiponectin receptors did not affect the suppressive effects of adiponectin on cell proliferation stimulated by these growth factors. These data collectively suggest that the oligomeric complexes of adiponectin can modulate the biological actions of several growth factors by controlling their bioavailability at a pre-receptor level and that this effect might partly account for the anti-atherogenic, anti-angiogenic, and anti-proliferative functions of adiponectin.
This study examined whether HIV counseling and testing leads to reductions in sexual risk behavior.
The meta-analysis included 27 published studies that provided sexual behavior outcome data, ...assessed behavior before and after counseling and testing, and provided details sufficient for the calculation of effect sizes. The studies involved 19,597 participants.
After counseling and testing, HIV-positive participants and HIV-serodiscordant couples reduced unprotected intercourse and increased condom use more than HIV-negative and untested participants. HIV-negative participants did not modify their behavior more than untested participants. Participants' age, volition for testing, and injection drug use treatment status, as well as the sample seroprevalence and length of the follow-up, explained the variance in results.
HIV counseling and testing appears to provide an effective means of secondary prevention for HIV-positive individuals but, as conducted in the reviewed studies, is not an effective primary prevention strategy for uninfected participants. Theory-driven research with attention given to the context of testing is needed to further explicate the determinants of behavior change resulting from HIV counseling and testing, and the effectiveness of specific counseling approaches.
Thermal–mechanical analysis of solidification is important to understand crack formation, shape problems, and other aspects of casting processes. This work investigates the effect of grade on ...thermal–mechanical behavior during initial solidification of steels during continuous casting of a wide strand. The employed finite element model includes non-linear temperature-, phase-, and carbon content-dependent elastic–viscoplastic constitutive equations. The model is verified using an analytical solution, and a mesh convergence study is performed. Four steel grades are simulated for 30 seconds of casting without friction: ultra-low-carbon, low-carbon, peritectic, and high-carbon steel. All grades show the same general behavior. Initially, rapid cooling causes tensile stress and inelastic strain near the surface of the shell, with slight complementary compression beneath the surface, especially with lower carbon content. As the cooling rate decreases with time, the surface quickly reverses into compression, with a tensile region developing toward the solidification front. Higher stress and inelastic strain are generated in the high-carbon steel, because it contains more high-strength austenite. Stress in the δ-ferrite phase near the solidification front is always very small, owing to the low strength of this phase. This modeling methodology is a step toward designing better mold taper profiles for continuous casting of different steels.
In mammals, dosage compensation is achieved by X inactivation and is regulated in cis by the X-inactivation centre (Xic) and Xist. The Xic controls X-chromosome counting, choice of X to inactivate ...and initiation of silencing. Xic action culminates in a change in Xist RNA property from a scarce, unstable RNA to highly expressed Xist RNA that coats the future inactive X. Deleting a 65-kb region downstream of Xist results in constitutive Xist expression and X inactivation, implying the presence of a cis-regulatory element. In this region, we now report the discovery of a gene antisense to Xist. Tsix is a 40-kb RNA originating 15 kb downstream of Xist and transcribed across the Xist locus. Tsix sequence is conserved at the human XIC. Tsix RNA has no conserved ORFs, is seen exclusively in the nucleus and is localized at Xic. Before the onset of X inactivation, Tsix is expressed from both X chromosomes. At the onset of X inactivation, Tsix expression becomes monoallelic, is associated with the future active X and persists until Xist is turned off. Tsix is not found on the inactive X once cells enter the X-inactivation pathway. Tsix has features suggesting a role in regulating the early steps of X inactivation, but not the silencing step.
Background and Objective
More than 100 salivary constituents have been found to show levels significantly different in patients with oral squamous cell carcinoma (OSCC) from those found in healthy ...controls, and therefore have been suggested to be potential salivary biomarkers for OSCC detection. However, many of these potential OSCC salivary biomarkers are also involved in chronic inflammation, and whether the levels of these biomarkers could be affected by the presence of chronic periodontitis was not known. The objective of this pilot study was therefore to measure the levels of seven previously reported potential OSCC salivary mRNA biomarkers in patients with chronic periodontitis and compare them to levels found in patients with OSCC and healthy controls. The seven salivary mRNAs were interleukin (IL)‐8, IL‐1β, dual specificity phosphatase 1, H3 histone family 3A, ornithine decarboxylase antizyme 1, S100 calcium‐binding protein P (S100P) and spermidine/spermine N1‐acetyltransferase 1.
Material and Methods
Unstimulated whole saliva samples were collected from a total of 105 human subjects from the following four study groups: OSCC; CPNS (chronic periodontitis, moderate to severe degree, non‐smokers); CPS (chronic periodontitis, moderate to severe degree, smokers); and healthy controls. Levels of each mRNA in patient groups (OSCC or chronic periodontitis) relative to the healthy controls were determined by a pre‐amplification reverse transcription–quantitative polymerase chain reaction approach with nested gene‐specific primers. Results were recorded and analyzed by the Bio‐Rad CFX96 Real‐Time System. Mean fold changes between each pair of patient vs. control groups were analyzed by the Mann–Whitney U‐test with Bonferroni corrections.
Results
Only S100P showed significantly higher levels in patients with OSCC compared to both patients with CPNS (p = 0.003) and CPS (p = 0.007). The difference in S100P levels between patients with OSCC and healthy controls was also marginally significant (p = 0.009). There was no significant difference in the levels of salivary IL‐8, IL‐1β and dual specificity phosphatase 1 mRNAs between patients with OSCC and patients with CPNS (p = 0.510, 0.058 and 0.078, respectively); no significant difference in levels of salivary ornithine decarboxylase antizyme 1 and spermine N1‐acetyltransferase mRNAs between patients with OSCC and patients with CPS (p = 0.318 and 0.764, respectively); and no significant difference in levels of the H3 histone family 3A mRNA between patients with OSCC and either CPS (p = 0.449) or healthy controls (p = 0.107).
Conclusions
Salivary S100P mRNA could be a reliable biomarker for OSCC detection, regardless of the presence of chronic periodontitis. The presence of chronic periodontitis could significantly affect the levels of the other six mRNAs, and negatively influence reliability for using them as biomarkers for oral cancer detection.
This article investigates pathways between the exposure to an entertainment-education (E-E) television drama called "Three Rivers" and positive discussion of organ donation among viewers of the drama ...in the United States. A cross-sectional survey was conducted using an online advertising for a period of one week. Survey participants included 1325 adults living in the United States, who had viewed the first episode of "Three Rivers" on television. Data were collected on recall of events in the storyline, perceived entertainment value, perceived accuracy of the presented health information, rejection of organ donation myths and positive discussion of organ donation and the storyline. Covariates were registration for organ donation, membership to the donation or transplant community and demographic variables. Results show that viewers with high recall of the storyline were more likely to reject myths about organ donation and engage in pro-donation discussions with others. Perceived entertainment value and perceived accuracy acted as mediators in such relationships. The insertion of accurate health information in television drama may be effective in promoting positive discussions about organ donation and myth rejection. Recall of events from the televised E-E drama "Three Rivers," entertainment value and accuracy perception were associated with positive discussion.
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