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Bird song is a classic example of a sexually selected trait, but much of the work relating individual song components to fitness has not accounted for song typically being composed of multiple, often-correlated components, necessitating a multivariate approach. We explored the role of sexual selection in shaping the complex male song of house wrens (Troglodytes aedon) by simultaneously relating its multiple components to fitness using multivariate selection analysis, which is widely used in insect and anuran studies but not in birds. The analysis revealed significant variation in the form and strength of selection acting on song across different selection episodes, from nest-site defense to recruitment of offspring to the breeding population. Males that sang more song typically employed in close communication sired more offspring that were subsequently recruited to the breeding population than those that sang more far-communication song. However, this relationship was not consistent across earlier selection episodes, as evidenced by non-linear selection acting on these song components in other contexts. Collectively, our results present a complex picture of multivariate selection on male song structure that would not be evident using univariate approaches and suggest possible trade-offs within and among song components at different points of the breeding season. [ABSTRACT FROM AUTHOR]

Differences in avian eggshell pigmentation could be an honest signal of female quality that males use to inform their nestling provisioning effort. We investigated whether among-individual variation in protoporphyrin-based eggshell pigmentation in house wrens (Troglodytes aedon) reflects female fitness-associated traits and whether males use that information. Females laying lighter clutches were older and larger than females laying darker clutches. Nestlings hatching from lighter clutches had greater size-corrected mass on post-hatch day 11, a measure that strongly predicts survival and recruitment to the breeding population. To test whether male provisioning effort responds to clutch pigmentation, we used a reciprocal clutch cross-fostering design, swapping dark with light clutches and light with dark; in controls, we swapped light with light clutches and dark with dark. Shortly before hatching, clutches were returned to their original nest to avoid confounding effects of nestling quality on male provisioning. Contrary to the sexual selection hypothesis, clutch pigmentation had no effect on male provisioning. Males were probably able to observe eggshell pigmentation and thus had information about female quality, but they did not use this information to modulate their nestling provisioning. This may be because of constraints on species-specific reproductive opportunities, or because variation in eggshell protoporphyrin serves other functions. [ABSTRACT FROM AUTHOR]

Sulfur mustard burns are characterized by delayed symptoms, slow healing, and recurrence after closure. Incomplete debridement at the level of the basement membrane is the postulated cause. Graham pioneered laser debridement of mustard burns. For field or mass-casualty use, saline wet-to-wet or antibiotic-soak debridement is more practical. In this study, we compared laser, saline, and antibiotic debridement in a porcine model of deep partial-thickness injury. Deep-dermal sulfur mustard burns were produced in 18 anesthetized Gottingen minipigs using 10-μl saturated vapor cap exposure time of 90 minutes. Debridement was started 48 hours postinjury and consisted of a single laser treatment; 5 days of 5% aqueous mafenide acetate wet-to-wet dressings; or 7 to 12 days of saline wet-to-wet dressings. Wounds were treated with daily silver sulfadiazine for 30 days and, then, assessed by histopathology, silver-ion analysis, colorimetry, and evaporimetry. All wounds healed well with no sign of infection. Antibiotic debridement showed no advantage over saline debridement. There were no significant differences between groups for colorimetry or evaporimetry. Histopathology was graded on a mustard-specific scale of 1 to 15 where higher values indicate better healing. Mean histology scores were 13.6 for laser, 13.9 for mafenide, and 14.3 for saline. Saline debridement statistically outperformed laser (P < .05) but required the longest debridement time. Laser debridement had the benefit of requiring a single treatment rather than daily dressing changes, significantly decreasing need for wound care and personnel resources. Development of a ruggedized laser for field use is a countermeasures priority. [ABSTRACT FROM AUTHOR]

Biparental care is a critical and, occasionally, unequally shared obligation that ensures that young survive to maturity. Such care may be complicated in systems in which one parent, typically the male, is unsure of his genetic relatedness to the young. Males may reduce paternal provisioning when full paternity is not assured, as occurs in mating systems in which females engage in extrapair copulations. Moreover, other factors independent of extrapair matings, such as male personality traits, likely also affect the level of paternal care. In this study, we determined the effect of a paternity threat event (i.e. a conspecific or a heterospecific territory intrusion) and male personality (i.e. the level of aggressiveness) on provisioning effort by male house wrens (Troglodytes aedon). Males were more likely to attack a conspecific intruder than a heterospecific intruder. Males that were exposed to a conspecific intruder were less likely to provision young at all. Of those males that did feed the young in their nest, male aggressiveness did not relate to feeding effort. These findings suggest that the likelihood of paternal care is reduced by perceived threats to paternity but that the costs of not feeding potentially multisired young are high and feeding efforts are unrelated to male personality. [ABSTRACT FROM AUTHOR]

Parental and territory quality are often correlated in territorial birds, and both factors influence the resources allocated to offspring. Surprisingly, the relative contribution of these two components of variation in parental investment remains obscure. We experimentally decoupled the normal covariation between parental quality and territory quality to test the hypothesis that territory quality influences female prenatal and postnatal reproductive allocation. Territories were categorized into low-, intermediate-, and high-quality based on fledging success of nests over the previous 6 years (nesting sites are fixed in space).To decouple covariation between territory quality and individual quality, nestbox entrance size was increased on high-quality territories and left small on poor-quality sites because house wrens (Troglodytes aedon) prefer small over large entrances to their nest sites. We found a significant prenatal effect of territory quality on nestling provisioning: when reared on intermediate-quality territories, nestlings hatching from eggs produced on low-quality territories were provisioned at a higher rate than those hatching from eggs produced on high-quality territories. We propose that the increased provisioning was brought about by increased nestling begging mediated by a maternally derived compound, such as corticosterone, transferred to the eggs of stressed females in poor-quality habitat. [ABSTRACT FROM AUTHOR]

Despite keen interest in extra-pair mating in birds, its adaptive significance remains unresolved. Here, we use a multi-year dataset to test whether traits of a female's social mate influence her propensity to produce extra-pair offspring in a population of house wrens, and whether producing extra-pair young has consequences for a female's fitness through effects on offspring survival. Females were most likely to produce extra-pair offspring when paired with old males and when paired with males on poor-quality territories, although this latter effect was marginally nonsignificant. Among offspring, the cutaneous immunity of within-pair young decreased as the age of their sires increased, but cutaneous immunity of extra-pair young was not affected by the age of their extra-pair sires or by the age of the males rearing them. Extra-pair offspring were more likely than within-pair offspring to return as breeding adults to the local population, with extra-pair sons being more likely to return as a breeder for multiple years. Our findings support the hypothesis that females produce extra-pair offspring to enhance their inclusive fitness beyond what they are capable of given the male with which they are socially paired. [ABSTRACT FROM AUTHOR]

In biparental species, conflict between the sexes is expected when optimal levels of parental care differ between males and females. We studied food provisioning in house wrens (Troglodytes aedon) to test whether male provisioning is more strongly affected than female provisioning by brood size, because this should influence the marginal return on a male’s investment. To test this, we created broods of reduced and enlarged size, and found that per-nestling food delivery varied more strongly for males than for females in association with brood size and nestling age; males delivered more food per nestling to enlarged broods, and less to small broods, as nestlings grew and approached asymptotic size. Although parents delivered a greater amount of prey to larger broods, the amount of food per nestling was initially higher for nestlings in small broods, and the amount of food delivered early in nestling development, particularly by males, affected offspring body mass, survival to fledging, and recruitment to the breeding population. However, provisioning rates were negatively associated with prey size, suggesting a trade-off between prey quantity and size. Finally, parents provisioning at a high rate to broods of reduced size were less likely to return to breed, suggesting that they assessed the low return on their investment and dispersed. Although potential for sexual conflict in house wrens remains, our data suggest that its resolution does not involve negotiation over provisioning, possibly because selection for offspring viability favors heavy investment by both parents.In biparental species, optimal levels of parental care for offspring should differ between males and females, and they are expected to ‘negotiate’ over how much to provide. Male food provisioning varied more strongly with brood size than female provisioning, which may reflect a form of negotiation over investment if females determine brood sizes and males respond accordingly. Food availability to offspring positively influenced whether they reproduced as adults, favoring heavy investment from both parents. [ABSTRACT FROM PUBLISHER]

Mothers adjust the sex of their offspring strategically to maximize fitness. Theory predicts that high-quality mothers should over-produce sons, but whether or not this occurs in nature is subject to debate. Here, we show that female house wrens capable of laying more eggs than normal produced a higher proportion of sons than females laying fewer eggs. Last-laid eggs were also more likely to contain daughters than earlier-laid eggs.Theory predicts that a mother’s ability to produce high-quality offspring should influence whether she produces sons or daughters. We tested this hypothesis in house wrens (Troglodytes aedon) using a within-clutch design in which we induced females to produce more eggs (8–10 eggs) than they normally would (6 or 7 eggs) to determine whether maternal effort and the allocation of resources to supernumerary eggs (those laid beyond the usual number) influence the offspring sex ratio. At the clutch level, we predicted that high-quality females, as defined by their ability to produce supernumerary eggs in response to egg removal, would overproduce sons relative to females treated the same way but producing fewer eggs. At the level of the egg, we predicted that supernumerary eggs would more likely contain daughters than sons. As predicted, females producing extralarge clutches overproduced sons and those producing smaller clutches produced relatively more daughters. Last-laid eggs were also more likely to contain daughters than earlier-laid eggs although there was no difference in the mass of eggs containing males and females. These results suggest that mothers adjust the sex of their offspring strategically to maximize fitness. [ABSTRACT FROM PUBLISHER]

Objectives and methods The present study’s objective was to evaluate serotonin toxicity with concomitant use of linezolid or comparators and serotonergic agents from 20 Phase III and IV comparator-controlled clinical studies on treatment of various Gram-positive infections. All reported adverse events were evaluated for serotonin toxicity using exact and surrogate terms consistent with Sternbach Criteria and Hunter Serotonin Toxicity Criteria. Results Baseline demographics and co-morbidities were similar between linezolid and comparator groups. No patients in either group were reported to have adverse events identified as serotonin toxicity. Among the patients receiving at least one serotonergic agent, 9 of the 2208 (0.41%) linezolid patients and 3 of the 2057 (0.15%) comparator patients met the Sternbach Criteria [risk ratio (RR) 2.79; 95% confidence interval (95% CI) 0.76–10.31]; 3 (0.14%) of the linezolid patients and 1 (0.05%) of the comparator patients met the Hunter Serotonin Toxicity Criteria (RR 2.79; 95% CI 0.29–26.85). No patients met both criteria. Most patients meeting criteria for serotonin toxicity had past or present co-morbidities that may have contributed to or overlapped with reported adverse events. Conclusions While the potential exists for serotonin toxicity to occur with concomitant use of linezolid and serotonergic agents, the risk appears to be low. Based on the large database of Phase III and IV studies included in our analysis, we did not find enough evidence to conclude that linezolid-induced serotonin toxicity was different from that of comparators. [ABSTRACT FROM PUBLISHER]

Female reproductive investment can vary according to their mate's attractiveness, and males may differentially invest according to their own attractiveness. Thus, when studying female parental investment, male investment must also be considered. We tested the hypothesis that the attractiveness of male house wrens (Troglodytes aedon) influences their investment independent of their own intrinsic quality by manipulating the number of nest sites (one = control; 4 = attractive) in each male's territory. Treatments (attractive or control) were applied prior to (natural state) or after (imposed state) male settlement, and male investment was determined twice during the nestling stage by the number of trips males made to the nest to provision their nestlings. Males that settled in the attractive territories were significantly older than those that settled in control territories in the natural state. There was a significant interaction effect between state and treatment on male provisioning. Provisioning rates of attractive and control males in the imposed state did not differ, but attractive males in the natural state provisioned at a lower rate than control males late in the nestling stage. Thus, provisioning by males is influenced more by their intrinsic quality than their attractiveness. [ABSTRACT FROM PUBLISHER]

The classical laboratory tests for exposure to organophosphorus toxicants (OP) are inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activity in blood. In a search for new biomarkers of OP exposure, we treated mice with a biotinylated organophosphorus agent, FP-biotin. The biotinylated proteins in muscle were purified by binding to avidin-Sepharose, separated by gel electrophoresis, digested with trypsin, and identified from their fragmentation patterns on a quadrupole time-of-flight mass spectrometer. Albumin and ES1 carboxylesterase (EC 3.1.1.1) were found to be major targets of FP-biotin. These FP-biotinylated proteins were also identified in mouse plasma by comparing band patterns on nondenaturing gels stained for albumin and carboxylesterase activity, with band patterns on blots hybridized with Streptavidin Alexa-680. Two additional FP-biotin targets, AChE (EC 3.1.1.7) and BChE (EC 3.1.1.8), were identified in mouse plasma by finding that enzyme activity was inhibited 50–80%. Mouse plasma contained eight additional FP-biotinylated bands whose identity has not yet been determined. In vitro experiments with human plasma showed that chlorpyrifos oxon, echothiophate, malaoxon, paraoxon, methyl paraoxon, diazoxon, diisopropylfluorophosphate, and dichlorvos competed with FP-biotin for binding to human albumin. Though experiments with purified albumin have previously shown that albumin covalently binds OP, this is the first report of OP binding to albumin in a living animal. Carboxylesterase is not a biomarker in man because humans have no carboxylesterase in blood. It is concluded that OP bound to albumin could serve as a new biomarker of OP exposure in man. [ABSTRACT FROM AUTHOR]

Acoustic measurements at 1.5–5 kHz on fish in the Gulf of Maine showed a swimbladder-resonance peak near 2.5 kHz at 160–190-m depth. Midwater trawls confirmed that the fish were likely to be Atlantic herring (Clupea harengus) of 19–29 cm length. Calculation using a model of swimbladder resonance gives swimbladder volumes of 1.2% of fish weight at 160–190 m. Extrapolation of this volume of gas using Boyle''s Law suggests that at the sea surface, these herring would need to inflate their swimbladders by up to five to six times the volume required for neutral buoyancy. If these fish were to maintain this volume of gas with surface “gulping”, they would need to submerge from the sea surface with a 30% excess buoyancy. In general, swimbladders of the Clupeidae may have greater volumes of gas than if the fish were neutrally buoyant at the sea surface and the interpretation of HF-echosounder surveys may be additionally complex when the volume of gas and swimbladder volume are difficult to predict. Mechanisms of how herring obtain additional swimbladder gas are discussed. [Copyright &y& Elsevier]

The objectives of this study were to develop competencies for wartime and operations other than war for 46N3 Medical/Surgical Air Force nurses and to validate those competencies among a group of experts in the field. The sample consisted of 109 nurses with mobilization experiences. A Delphi consensus technique was used to validate both the importance of competencies required in a mobilization environment and to determine the level at which those competencies should be practiced. A web-based questionnaire was used to collect responses during three rounds of data collection. At the end of round 3, 83% of the importance statements achieved consensus whereas 67% of the level of practice statements achieved consensus. Those importance items validated were traditional assessment and interventions skills that represented noncontroversial practices. Those items not validated were either controversial or perceived as not pertinent in an austere mobilization environment. [ABSTRACT FROM AUTHOR]

Presents a study which tested the sex-ratio adjustment hypothesis predicting that female House Wrens should modify offspring sex ratios according to the potential reproductive success of their offspring under existing ecological conditions. Conditions when parents should produce male or female offsprings; Explanation for the unchanged sex ratio during the course of the breeding season; Reason for the biased nestling sex ratios at fledging.

The heightened worldwide recognition of the health burden of tickborne infection derives largely fromthe increasing incidence of Lyme disease, human babesiosis, and human granulocytic ehrlichiosis, both individually and in concert. Because these infections share the same rodent reservoir and tick vector hosts, they can be cotransmitted to human hosts. Indeed, human coinfections involving various combinations of these pathogens are common, and some tend to be particularly severe. Diagnostic procedures and clinical management of the resulting disease syndrome is rendered complex by the diversity of pathogens involved and by the unusual diversity and duration of symptoms. [ABSTRACT FROM AUTHOR]

Presents a study which tested the hypothesis proposing that female House Wren in poor physical condition postpones incubation and hatches their clutches synchronously. Cause of asynchronous hatching in birds; Differences in reproductive success between synchronously and asynchronously hatching clutches; Methods used; Results; Discussion.

Broadband low-frequency measurements have been used in conjunction with a fish swimbladder scattering model to determine size distributions and areal densities of well-known populations of dispersed fishes. The method has also been used to identify and estimate the abundance of deep-dwelling fishes that are generally beyond the range of high-frequency echo-sounders. It can also be used to examine swimbladder behavior. Results on five fish species in three widespread locations are presented to demonstrate the capabilities of the method. [ABSTRACT FROM PUBLISHER]

Current models explaining the establishment and maintenance of social monogamy and polygyny within avian populations typically assume that the reproductive success of polygynous males exceeds that of monogamous males. This assumption is almost always supported when the number of fledglings or recruits to future breeding populations is used tomeasure adult reproductive success. However, recent studies using DNA markers indicate that simple counts of fledglings or recruits may be a poor estimator of the number of nestlings sired by the social father. In this paper, we compare the number of genetic offspring produced by so monogamous and polygynous house wren (Troglodytes aedon) males in nests at which they were the social father. Polygynous males did, in fact, sire more nestlings in their own nests than did monogamous males. Moreover, although we have not identified the sires of extrapair nestlings, we document that even when all extrapair nestlings inthis population are hypothetically assigned to monogamous males, thetotal reproductive success of polygynous males exceeds that of monogamous males. These results and those of several other recent studies are consistent with the assumption that polygynous males produce moreoffspring than monogamous males. [ABSTRACT FROM AUTHOR]