bluuebunny/crossref_metadata_2025_split huggingface dataset:
Directional mitochondrial introgression and character displacement due to reproductive interference in two closely related Pterostichus ground beetle species
Authors: Kosuda S. , Sasakawa K. , Ikeda H. 
Published: February 2016

AbstractReproductive interference due to interspecific hybridization can lead to character displacement among related species with overlapping ranges. However, no studies have examined which reproductive traits are most important in reducing reproductive interference. We conducted molecular analyses of two nuclear genes (28S and Wingless) and a mitochondrial gene (COI) from two closely related ground beetle species, Pterostichus thunbergi and Pterostichus habui (Coleoptera: Carabidae), with overlapping distributions. In addition, we examined four reproductive traits (body size, organ morphologies of intromittent and non‐intromittent male genital organs, and female reproductive period) in sympatric and allopatric habitats. We compared male genital morphology using geometric morphometric analysis. The species determined by morphology were classified into separate groups based on the phylogenetic tree constructed by the nuclear gene (Wingless). However, according to the mitochondrial genes examined, P. thunbergi was not monophyletic, whereas at the sympatric sites, these species formed a monophyletic clade. This incongruence suggests that interspecific hybridization and subsequent mitochondrial introgression from P. habui to P. thunbergi have occurred. Concerning genital morphology, both of the intromittent and nonintromittent organs of P. thunbergi differed more from P. habui at the sympatric sites than between allopatric sites, suggesting reproductive character displacement. Pterostichus thunbergi, which likely arrived in P. habui habitat in small numbers, would have experienced stronger selection pressures than P. habui.
Variation in pre‐treatment count lead time and its effect on baseline estimates of cage‐level sea lice abundance
Authors: Gautam R , Boerlage A S , Vanderstichel R , Revie C W , Hammell K L 
Published: February 2016

AbstractTreatment efficacy studies typically use pre‐treatment sea lice abundance as the baseline. However, the pre‐treatment counting window often varies from the day of treatment to several days before treatment. We assessed the effect of lead time on baseline estimates, using historical data (2010–14) from a sea lice data management programme (Fish‐iTrends). Data were aggregated at the cage level for three life stages: (i) chalimus, (ii) pre‐adult and adult male and (iii) adult female. Sea lice counts were log‐transformed, and mean counts by lead time relative to treatment day were computed and compared separately for each life stage, using linear mixed models. There were 1,658 observations (treatment events) from 56 sites in 5 Bay Management Areas. Our study showed that lead time had a significant effect on the estimated sea lice abundance, which was moderated by season. During the late summer and autumn periods, counting on the day of treatment gave significantly higher values than other days and would be a more appropriate baseline estimate, while during spring and early summer abundance estimates were comparable among counts within 5 days of treatment. A season‐based lead time window may be most appropriate when estimating baseline sea lice levels.
Hospitalisation in adults with intellectual disabilities compared with the general population in Norway
Authors: Skorpen S. , Nicolaisen M. , Langballe E. M. 
Published: February 2016

AbstractBackgroundPrevious studies have found that adults with intellectual disabilities (ID) are hospitalised more often than the general population (GP). This study investigates hospital discharge rates and main diagnostic causes for hospitalisation among administratively defined people with ID compared with the GP in Norway.MethodData from the Norwegian Labour and Welfare Service was combined with data from the Norwegian Patient Register (Ntotal = 1 764 072 and NID = 7573) for the period 2008–2011. Data from a Norwegian patient report generator and Statistics Norway are also analysed.ResultsDuring the study period, 11% of people with ID and 11.5% of the GP were admitted to hospitals. The length of the average hospital stay was just over 4 days for both groups. Among those who were hospitalised, the majority were only admitted to hospital once during the study period: ID 66% and GP 70%. People with ID were admitted somewhat more often than people in the GP. Contrary to the GP, adults with ID were more frequently hospitalised at a younger age and less frequently at old age. The most common International Classification of Diseases diagnostic group for hospitalisation among people with ID is injury, poisoning and certain other consequences of external causes, whereas for the GP, it is diseases of the circulatory system.ConclusionThis study finds that the proportion of people being hospitalised per year is statistically, but only slightly, different among adult people with ID and the GP. The results must be interpreted in light of the organisation of the health care system in Norway.
Evaluation of whole cell fixation methods for the analysis of nanoscale surface features of Yersinia pestis KIM
Authors: WANG C. , STANCIU C.E. , EHRHARDT C.J. , YADAVALLI V.K. 
Published: February 2016

SummaryManipulation of viable Yersinia pestis (etiologic agent of plague) in the laboratory usually necessitates elevated biosafety and biocontainment procedures, even with avirulent or vaccine strains. To facilitate downstream biochemical or physical analyses in a Biosafety Level 1 laboratory environment, effective inactivation without affecting its intrinsic properties is critical. Here, we report on the morphological and biochemical changes to Y. pestis surfaces following four different fixation methods that render the cells nonviable. The results, obtained at the single cell level, demonstrate that methanol inactivation is best able to preserve bacterial morphology and bioactivity, enabling subsequent analysis. This nanoscale evaluation of the effects of inactivation on cell morphology and surface bioactivity may provide a crucial preparatory approach to study virulent pathogens in the lab setting using high‐resolution microscopic techniques such as atomic force microscopy.
Kicking Off Social Entrepreneurship: How A Sustainability Orientation Influences Crowdfunding Success
Authors: Calic Goran , Mosakowski Elaine 
Published: February 2016

AbstractResearch generally suggests that, relative to commercial entrepreneurs, social entrepreneurs stand at a disadvantage at acquiring resources through traditional financial institutions. Yet interest in social entrepreneurship appears to be at an all‐time high. The current paper advances the argument that an innovative institutional form – crowdfunding – has emerged to address the needs of social entrepreneurs and other entrepreneurs with limited access to traditional sources of capital. To examine this, we study whether and how a sustainability orientation affects entrepreneurs’ ability to acquire financial resources through crowdfunding and hypothesize that a venture's sustainability orientation will enhance its fundraising capability. We also suggest that project legitimacy and creativity mediate the relationship between a sustainability orientation and funding success. Our analysis produces two key findings: 1) a sustainability orientation positively affects funding success of crowdfunding projects, and 2) this relationship is partially mediated by project creativity and third party endorsements.
Atherosclerotic Carotid Plaque Composition: A 3T and 7T MRI‐Histology Correlation Study
Authors: Lopez Gonzalez M.R. , Foo S.Y. , Holmes W.M. , Stewart W. , Muir K.W. , Condon B. , Welch G. , Forbes K.P. 
Published: February 2016

ABSTRACTBACKGROUND AND PURPOSECarotid artery atherosclerotic plaque composition may influence plaque stability and risk of thromboembolic events, and noninvasive plaque imaging may therefore permit risk stratification for clinical management. Plaque composition was compared using noninvasive in vivo (3T) and ex vivo (7T) MRI and histopathological examination.METHODSThirty‐three endarterectomy cross‐sections, from 13 patients, were studied. The data sets consisted of in vivo 3T MRI, ex vivo 7T MRI, and histopathology. Semiautomated segmentation methods were used to measure areas of different plaque components. Bland‐Altman plots and mean difference with 95% confidence interval were carried out.RESULTSThere was general quantitative agreement between areas derived from semiautomated segmentation of MRI data and histology measurements. The mean differences and 95% confidence bounds in the relative to total plaque area between 3T versus Histology were: fibrous tissue 4.99%(–4.56 to 14.56), lipid‐rich/necrotic core (LR/NC) with hemorrhage –1.81%(–14.11 to 10.48), LR/NC without hemorrhage –2.43%(–13.04 to 8.17), and calcification –3.18%(–11.55 to 5.18). The mean differences and 95% confidence bounds in the relative to total plaque area between 7T and histology were: fibrous tissue 3.17%(–3.17 to 9.52), LR/NC with hemorrhage –0.55%(–9.06 to 7.95), LR/NC without hemorrhage –12.62%(–19.8 to –5.45), and calcification –2.43%(–9.97 to 4.73).CONCLUSIONSThis study provides evidence that semiautomated segmentation of 3T/7T MRI techniques can help to determine atherosclerotic plaque composition. In particular, the high resolution of ex vivo 7T data was able to highlight greater detail in the atherosclerotic plaque composition. High‐field MRI may therefore have advantages for in vivo carotid plaque MRI.
In Vitro Assessment of the Abrasion Resistance of Two Types of Artificial Teeth Submitted to Brushing
Authors: Policastro Vivian Barnabé , Giro Gabriela , Leite Andressa Rosa Perin , Mendoza‐Marin Danny Omar , Paleari André Gustavo , Compagnoni Marco Antonio , Pero Ana Carolina 
Published: February 2016

AbstractPurposeTo assess the effect of brushing with different solutions on the abrasion resistance of two types of acrylic resin teeth.Materials and MethodsMaxillary premolars from two types of acrylic teeth (Biotone and Biotone IPN) were divided into six groups (n = 12), according to the solution used during brushing: distilled water (control), coconut soap, or dentifrice. A mechanical brushing machine was used to simulate approximately 1 year of brushing (11,000 strokes). The weight loss (WL) of teeth was obtained from the difference between the initial (IW) and final weight (FW) of each specimen, and the mean of percentage of weight loss (PWL) was calculated for each group. Data were analyzed using the Kruskal‐Wallis test, followed by Bonferroni's post‐test comparison (α = 0.05).ResultsA statistically significant difference was found for the factor solution (p < 0.001). Brushing using dentifrice caused the highest values of weight loss (–0.50%), in comparison with the groups brushed with coconut soap (0.00%) or distilled water (0.00%).ConclusionsFor both types of artificial teeth, brushing with dentifrice produced higher abrasion than brushing with coconut soap or water.
Reliability and Failure Modes of a Hybrid Ceramic Abutment Prototype
Authors: Silva Nelson RFA , Teixeira Hellen S. , Silveira Lucas M. , Bonfante Estevam A. , Coelho Paulo G. , Thompson Van P. 
Published: February 2016

AbstractPurposeA ceramic and metal abutment prototype was fatigue tested to determine the probability of survival at various loads.Materials and MethodsLithium disilicate CAD‐milled abutments (n = 24) were cemented to titanium sleeve inserts and then screw attached to titanium fixtures. The assembly was then embedded at a 30° angle in polymethylmethacrylate. Each (n = 24) was restored with a resin‐cemented machined lithium disilicate all‐ceramic central incisor crown. Single load (lingual‐incisal contact) to failure was determined for three specimens. Fatigue testing (n = 21) was conducted employing the step‐stress method with lingual mouth motion loading. Failures were recorded, and reliability calculations were performed using proprietary software. Probability Weibull curves were calculated with 90% confidence bounds. Fracture modes were classified with a stereomicroscope, and representative samples imaged with scanning electron microscopy.ResultsFatigue results indicated that the limiting factor in the current design is the fatigue strength of the abutment screw, where screw fracture often leads to failure of the abutment metal sleeve and/or cracking in the implant fixture. Reliability for completion of a mission at 200 N load for 50K cycles was 0.38 (0.52% to 0.25 90% CI) and for 100K cycles was only 0.12 (0.26 to 0.05)—only 12% predicted to survive. These results are similar to those from previous studies on metal to metal abutment/fixture systems where screw failure is a limitation. No ceramic crown or ceramic abutment initiated fractures occurred, supporting the research hypothesis. The limiting factor in performance was the screw failure in the metal‐to‐metal connection between the prototyped abutment and the fixture, indicating that this configuration should function clinically with no abutment ceramic complications.ConclusionThe combined ceramic with titanium sleeve abutment prototype performance was limited by the fatigue degradation of the abutment screw. In fatigue, no ceramic crown or ceramic abutment components failed, supporting the research hypothesis with a reliability similar to that of all‐metal abutment fixture systems. A lithium disilcate abutment with a Ti alloy sleeve in combination with an all‐ceramic crown should be expected to function clinically in a satisfactory manner.
Percentage of REM sleep is associated with overnight change in leptin
Authors: Olson Christy A. , Hamilton Nancy A. , Somers Virend K. 
Published: February 2016

SummarySleep contributes importantly to energy homeostasis, and may impact hormones regulating appetite, such as leptin, an adipocyte‐derived hormone. There is increasing evidence that sleep duration, and reduced rapid eye movement sleep, are linked to obesity. Leptin has central neural effects beyond modulation of appetite alone. As sleep is not a unifrom process, interactions between leptin and sleep stages including rapid eye movement sleep may play a role in the relationship between sleep and obesity. This study examined the relationship between serum leptin and rapid eye movement sleep in a sample of healthy adults. Participants were 58 healthy adults who underwent polysomnography. Leptin was measured before and after sleep. It was hypothesized that a lower percentage of rapid eye movement sleep would be related to lower leptin levels during sleep. The relationship between percentage of rapid eye movement sleep and leptin was analysed using hierarchical linear regression. An increased percentage of rapid eye movement sleep was related to a greater reduction in leptin during sleep even when controlling for age, gender, percent body fat and total sleep time. A greater percentage of rapid eye movement sleep was accompanied by more marked reductions in leptin. Studies examining the effects of selective rapid eye movement sleep deprivation on leptin levels, and hence on energy homeostasis in humans, are needed.
Sampling effort required to recover the main gradients in marine benthic species composition
Authors: van Son Thijs Christiaan , Halvorsen Rune , Bakke Torgeir 
Published: February 2016

AbstractMarine benthic surveys and monitoring programs may have several goals. When the aim of such studies is to reveal and describe gradients in species composition, the gain in ecological insight achieved by the study depends on how well the spatial variability of species’ occurrence and abundance within the study area is covered by the sampling design. The common practice in such programs is to collect four or five grab samples from each visited site to capture the site's species composition. The rationale for this practice is based on the aim of capturing a large proportion of species at a specific site (i.e. point). We argue that this practice has been established without taking Iterative approaches into account, such as decreasing the sampling effort at each site and instead increase the number of sites visited. The collection and processing of data from marine sediment ecosystems are time‐consuming and, thus, expensive. Therefore, finding the optimal trade‐off between the number of sites visited and the number of samples per site is important. We examined this trade‐off by exploring how reduction of sampling effort per site affects the stability and recovery of gradients in species composition of marine benthic macrofauna. Our full data set consisted of four grab samples from each of 28 sites from the inner part of the Oslofjord, SE Norway. Procrustes analysis and calculation of Kendall's rank correlation coefficients showed that the main gradient in species composition extracted by detrended correspondence analysis of data sets with reduced per‐site sampling effort closely resembled the main gradient extracted for the full data set. Our results therefore suggest that marine benthic surveys that aim to identify the main gradient structure of species composition and relate this structure to main environmental complex gradients are likely to benefit from reducing the sampling effort at each site and, instead, increasing the number of visited sites. We argue that coverage of both the variation in species composition and the environment in the study area will then be improved. Monitoring programs with other aims than to identify the main gradients in species composition may also benefit from the adoption of a many‐sites, one‐sample sampling strategy. This may be particularly true if additional sampled sites are based on a stratified sampling strategy that ensures that the spatial variability in the study area is accounted for.
Efficiency of calcein tagging on juveniles of the sea urchins Diadema africanum and Paracentrotus lividus
Authors: Rodríguez Adriana , Hernández José Carlos , Clemente Sabrina 
Published: February 2016

AbstractWe evaluated the effectiveness of chemical tagging with the fluorescent marker calcein for two key species of herbivorous sea urchins, Diadema africanum and Paracentrotus lividus, to facilitate medium‐ and long‐term ecological experiments. In total, 98 juveniles of D. africanum and 98 P. lividus were tagged with this fluorescent marker, with 12 combinations of different tagging techniques (chemical bath or injection), concentrations of calcein (2, 10 and 20 mg · l−1), and soaking times (2, 4 and 24 h). Respective control treatments were conducted by means of seawater injection and bathing. The success of tagging was assessed after a month of feeding individuals ad libitum with the algae Dictyota sp. Sea urchins were dissected and their Aristotle's lanterns cleaned with 10% sodium hypochlorite to examine these structures under UV light using a binocular microscope. Each species was evaluated in terms of survival, percentage of tagged individuals and intensity of the resulting tag. The results showed that the method of soaking individuals of both species for 24 h in concentrations of calcein of 10 and 20 mg · l−1 gave the highest percentage survival (100%) and the resulting tags were clearly visible.
Type IV traffic ATPase TrwD as molecular target to inhibit bacterial conjugation
Authors: Ripoll‐Rozada Jorge , García‐Cazorla Yolanda , Getino María , Machón Cristina , Sanabria‐Ríos David , de la Cruz Fernando , Cabezón Elena , Arechaga Ignacio 
Published: February 2016

SummaryBacterial conjugation is the main mechanism responsible for the dissemination of antibiotic resistance genes. Hence, the search for specific conjugation inhibitors is paramount in the fight against the spread of these genes. In this pursuit, unsaturated fatty acids have been found to specifically inhibit bacterial conjugation. Despite the growing interest on these compounds, their mode of action and their specific target remain unknown. Here, we identified TrwD, a Type IV secretion traffic ATPase, as the molecular target for fatty acid‐mediated inhibition of conjugation. Moreover, 2‐alkynoic fatty acids, which are also potent inhibitors of bacterial conjugation, are also powerful inhibitors of the ATPase activity of TrwD. Characterization of the kinetic parameters of ATPase inhibition has led us to identify the catalytic mechanism by which fatty acids exert their activity. These results open a new avenue for the rational design of inhibitors of bacterial conjugation in the fight against the dissemination of antibiotic resistance genes.
Acyldepsipeptide antibiotics kill mycobacteria by preventing the physiological functions of the ClpP1P2 protease
Authors: Famulla Kirsten , Sass Peter , Malik Imran , Akopian Tatos , Kandror Olga , Alber Marina , Hinzen Berthold , Ruebsamen‐Schaeff Helga , Kalscheuer Rainer , Goldberg Alfred L. , Brötz‐Oesterhelt Heike 
Published: February 2016

SummaryThe Clp protease complex in Mycobacterium tuberculosis is unusual in its composition, functional importance and activation mechanism. Whilst most bacterial species contain a single ClpP protein that is dispensable for normal growth, mycobacteria have two ClpPs, ClpP1 and ClpP2, which are essential for viability and together form the ClpP1P2 tetradecamer. Acyldepsipeptide antibiotics of the ADEP class inhibit the growth of Gram‐positive firmicutes by activating ClpP and causing unregulated protein degradation. Here we show that, in contrast, mycobacteria are killed by ADEP through inhibition of ClpP function. Although ADEPs can stimulate purified M. tuberculosis ClpP1P2 to degrade larger peptides and unstructured proteins, this effect is weaker than for ClpP from other bacteria and depends on the presence of an additional activating factor (e.g. the dipeptide benzyloxycarbonyl‐leucyl‐leucine in vitro) to form the active ClpP1P2 tetradecamer. The cell division protein FtsZ, which is a particularly sensitive target for ADEP‐activated ClpP in firmicutes, is not degraded in mycobacteria. Depletion of the ClpP1P2 level in a conditional Mycobacterium bovis BCG mutant enhanced killing by ADEP unlike in other bacteria. In summary, ADEPs kill mycobacteria by preventing interaction of ClpP1P2 with the regulatory ATPases, ClpX or ClpC1, thus inhibiting essential ATP‐dependent protein degradation.
Monitoring population‐level responses of marine mammals to human activities
Authors: Fleishman Erica , Costa Daniel P. , Harwood John , Kraus Scott , Moretti David , New Leslie F. , Schick Robert S. , Schwarz Lisa K. , Simmons Samantha E. , Thomas Len , Wells Randall S. 
Published: February 2016

AbstractWe provide guidance for monitoring whether human activities affect the physiology or behavior of marine mammals and, if so, whether those effects may lead to changes in survival and reproduction at the population level. We suggest that four elements be included in designing and implementing such a monitoring program. The first is development of a theory of change: a set of mechanistic hypotheses that outline why a given activity might be expected to have one or more measurable effects on individuals and populations, and ideally the magnitude, timing, and duration of the effects. The second element, definition of biologically meaningful effect sizes, ultimately facilitates the development of a monitoring program that can detect those magnitudes of effect with the desired levels of precision. The third element, selection of response variables for monitoring, allows inference to whether observed changes in the status of individuals or populations are attributable to a given activity. Visual observations, passive acoustic and tagging instruments, and direct physical measurements all can provide data that facilitate quantitative hypothesis testing. The fourth element is specification of the temporal sequence of monitoring. These elements also can be used to inform monitoring of the responses of other taxonomic groups to human activities.