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Physiological consequences of rising water salinity for a declining freshwater turtle.
Sea-level rise, drought and water diversion can all lead to rapid salinization of freshwater habitats, especially in coastal areas. Increased water salinities can in turn alter the geographic distribution and ecology of freshwater species including turtles. The physiological consequences of salinization for freshwater turtles, however, are poorly known. Here, we compared the osmoregulatory response of two geographically separate populations of the freshwater Western Pond Turtle (Actinemys marmorata)-a species declining across its range in western North America-to three constant salinities: 0.4Â ppt, 10Â ppt and 15Â ppt over 2Â weeks. We found that turtles from a coastal estuarine marsh population regulated their plasma osmolality at lower levels than their conspecifics from an inland freshwater creek population 45Â km away. Plasma osmolalities were consistently lower in estuarine marsh turtles than the freshwater creek turtles over the entire 2-week exposure to 10Â ppt and 15Â ppt water. Furthermore, estuarine marsh turtles maintained plasma osmolalities within 1 SD of their mean field osmolalities over the 2-week exposure, whereas freshwater creek turtles exceeded their field values within the first few days after exposure to elevated salinities. However, individuals from both populations exhibited body mass loss in 15Â ppt water, with significantly greater loss in estuarine turtles. We speculate that the greater ability to osmoregulate by the estuarine marsh turtles may be explained by their reduced feeding and drinking in elevated salinities that was not exhibited by the freshwater creek population. However, due to mass loss in both populations, physiological and behavioural responses exhibited by estuarine marsh turtles may only be effective adaptations for short-term exposures to elevated salinities, such as those from tides and when traversing saline habitats, and are unlikely to be effective for long-term exposure to elevated salinity as is expected under sea-level rise
An alginate hydrogel dura mater replacement for use with intracortical electrodes
The collagenous dura mater requires a secure closure following implantation of neural prosthetic devices to avoid complications due to cerebrospinal fluid leakage and infections. Alginate was previously suggested for use as a dural sealant. The liquid application and controllable gelling conditions enable alginate to conform to the unique geometries of a neural prosthetic device and the surrounding dura mater to create a barrier with the external environment. In this study, we evaluated the use of alginate as a method to securely reclose a dural defect and seal around an untethered microscale neural probe in the rabbit model. After 3 days and 3 weeks, the sealing strength of alginate remained eight times greater than normal rabbit intracranial pressure and similar in both the presence and absence of a penetrating neural probe. For time points up to 3 months, there was no significant difference in dura mater fibrosis or thickness between alginate and controls. Application of alginate to a dural defect results in a watertight seal that remains intact while the dura mater reforms. These findings indicate that alginate is an effective tool for sealing around microscale neural probes and suggests broader application as a sealant for larger neural prosthetic devices. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78236/1/31733_ftp.pd
Industry cognitive distance in alliances and firm innovation performance
This paper focuses on the role of industry cognitive distance in innovation alliances on firm innovation performance. Drawing from the literature on technological cognitive distance in alliances, we elaborate on the role of industry cognitive distance between partners and its impact on managerial attention to investigate the role of numbers of alliances of low (intraâindustry) and high (interâindustry) industry cognitive distance on firm innovation performance. Intraâindustry alliances offer lower opportunities for innovation compared to interâindustry alliances and are less demanding on firm management due to higher cognitive similarity between partners from the same industry. We propose that tradeâoffs between innovation opportunities and management efforts result in an inverted U and a Uâshaped relationship between the number of intraâ and interâindustry alliances and innovation performance, respectively. We find support for both hypotheses in the context of the UK bioâpharmaceutical sector
Punching above their weight: a network to understand broader determinants of increasing life expectancy
BACKGROUND: Life expectancy initially improves rapidly with economic development but then tails off. Yet, at any
level of economic development, some countries do better, and some worse, than expected â they either punch
above or below their weight. Why this is the case has been previously researched but no full explanation of the
complexity of this phenomenon is available.
NEW RESEARCH NETWORK: In order to advance understanding, the newly formed Punching Above Their Weight
Research Network has developed a model to frame future research. It provides for consideration of the following
INFLUENCES WITHIN A COUNTRY: political and institutional context and history; economic and social policies; scope for
democratic participation; extent of health promoting policies affecting socio-economic inequities; gender roles and
power dynamics; the extent of civil society activity and disease burdens.
CONCLUSION: Further research using this framework has considerable potential to advance effective policies to
advance health and equity
Factors associated with disease evolution in Greek patients with inflammatory bowel disease
BACKGROUND: The majority of Crohn's disease patients with B1 phenotype at diagnosis (i.e. non-stricturing non-penetrating disease) will develop over time a stricturing or a penetrating pattern. Conflicting data exist on the rate of proximal disease extension in ulcerative colitis patients with proctitis or left-sided colitis at diagnosis. We aimed to study disease evolution in Crohn's disease B1 patients and ulcerative colitis patients with proctitis and left-sided colitis at diagnosis. METHODS: 116 Crohn's disease and 256 ulcerative colitis patients were followed-up for at least 5 years after diagnosis. Crohn's disease patients were classified according to the Vienna criteria. Data were analysed actuarially. RESULTS: B1 phenotype accounted for 68.9% of Crohn's disease patients at diagnosis. The cumulative probability of change in disease behaviour in B1 patients was 43.6% at 10 years after diagnosis. Active smoking (Hazard Ratio: 3.01) and non-colonic disease (non-L2) (Hazard Ratio: 3.01) were associated with behavioural change in B1 patients. Proctitis and left-sided colitis accounted for 24.2%, and 48.4% of ulcerative colitis patients at diagnosis. The 10 year cumulative probability of proximal disease extension in patients with proctitis and left-sided colitis was 36.8%, and 17.1%, respectively (p: 0.003). Among proctitis patients, proximal extension was more common in non-smokers (Hazard Ratio: 4.39). CONCLUSION: Classification of Crohn's disease patients in B1 phenotype should be considered as temporary. Smoking and non-colonic disease are risk factors for behavioural change in B1 Crohn's disease patients. Proximal extension is more common in ulcerative colitis patients with proctitis than in those with left-sided colitis. Among proctitis patients, proximal extension is more common in non-smokers
Tragicomic presentations of self : starring Phil Silvers as Bilko : the incomplete comic human
When a performer becomes over-associated with a particular, celebrated comic character can this lead to problems, not merely in terms of type-casting, but in creating confusions for the actorâs own perception of self? In instances where a comic creation is perceived to be an extension of the performerâs actual âselfâ, what dissonances in self construct may arise between the comic actorâs created persona and his/her own presentation of self? This article considers the nature of tensions created through the permeation of persona and person which can beset comedians who become closely identified with their particular mediated role. Can, indeed, over-association with their successful âsignatureâ comic role be seen to prove psychologically destabilising for certain performers whose own fragile, sense of identity becomes further compromised by presentation of their own most familiar and definitive, comic creations? Drawing specifically upon the career and comedy of Phil Silvers (aka âSergeant âBilkoâ), this article attempts to evaluate the forms of crises of identity that can arise between presentations of public and private selves for those performers who become, in effect, âpublic comic propertyâ
An investigation of prescribed and nonprescribed medicine use behavior within the household context
The goal of this study was to study empirically individual and household characteristics and their relation to individual medicine use behavior. The study accounted for 40% of the variance in prescribed medicine use and 20% of the variance in nonprescribed medicine use behavior for 545 AFDC households in Northern Mississippi. Perceived morbidity was the primary mediator of medicine use and 57% of the explained variance in nonprescribed medicine use. Age was a significant contributor to the variance explained in prescribed medicine use behavior. The use of nonprescribed medicines by other members of the household also significantly enhanced individual nonprescribed medicine use. Although many of the other individual and household variables were significant predictors of medicine use behavior they contributed little to the total explained variance. Research concerning medicine use in the context of the household is in the initial stage of theory development.
A Child's Day at School: Variations in More and Less Effective Schools in Low- and Middle-Socioeconomic Status Contexts
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