bluuebunny/crossref_metadata_2025 huggingface dataset:
Repeatability of decision-making behaviour in male threespine stickleback Gasterosteus aculeatus: Effects of dummy vs. live stimuli
Authors: Dzieweczynski Teresa L. , Forrette Lindsay M.
Published: February 2016

Individuals select from a number of behaviours when responding to various situations and the decisions they make may affect their fitness. The costs and benefits of these responses vary among individuals causing them to differ even in identical situations. One example of this type of situation is when territorial males encounter both a male and female simultaneously, generating a trade-off that likely leads to individual differences due to differing costs of various actions among males. This situation commonly occurs in threespine stickleback, Gasterosteus aculeatus. However, for selection to act effectively, individuals must behave in a consistent manner and measuring repeatability can aid in understanding how selection may shape such trade-offs. Males of this species exhibit consistent individual differences in their response to dummy males and females but it is unknown if patterns are similar when feedback from the stimuli is present. To assess this, male threespine stickleback were tested with dummy and live male and female conspecifics, presented separately and simultaneously. While the same trends were found regardless of stimulus type, males were more aggressive towards the live conspecifics than to the dummies. Repeatability values were similar within a treatment regardless of whether live or dummy conspecifics were used, suggesting that individuals show the same level of consistency. This study adds to our understanding of consistent individual differences by demonstrating that feedback may not affect responses to conflicting stimuli and that male threespine stickleback respond in a consistent manner to both dummy and live stimuli.
Differences in hoarding behavior between captive and wild sympatric rodent species
Authors: Zhang Hongmao , Wang Yu
Published: February 2016

In hand reared birds and mammals, it is generally considered that the development of hoarding behavior is the result of an interaction between the development and maturation of the nervous system and learning from individual experience. However, few studies have been done on wild animals. We tested differences in hoarding behavior between captive reared and wild individuals of two sympatric small rodents, Korean field mice Apodemus peninsulae and Chinese white-bellied rats Niviventer confucianus. Our aim was to identify if lack of experience from the wild would result in poorly developed hoarding behavior. The Korean field mice perform scatterand larder-hoarding behaviors whereas Chinese white-bellied rats hoard food in larders only. Within outdoor enclosures we compared seed-hoarding behavior in reared juveniles (RJ, 40-50 d old, pregnant mothers were captured in the wild), wild juveniles (WJ, as young as the RJ) and wild adults (WA, over-winter animals). We found that a lack of experience from the wild had significant effects on seed-hoarding behavior for both species. The RJ-group removed and hoarded fewer seeds than the WJand WA-groups. The two latter groups hoarded seeds in a similar way. In the Korean filed mouse the RJ-group placed more seeds on the ground surface than other groups. These findings suggest that wild experience is important for the acquisition of an appropriate food-hoarding behavior (especially for scatter-hoarding) in these species.
Age and body size of Rana amurensis from northeastern China
Authors: Chen Wei , Lu Xin
Published: February 2016

Age and body size are two important demographic traits that determine the life history strategies of populations and species. We measured these two parameters of Rana amurensis, at a 900 m and a 500 m altitude site in northeastern China. At the two sites, age at first reproduction was 2 years for males and 3 years for females. The maximum age of males and females at the high-altitude site was 6 and 7 years, and 5 and 7 years at the low-altitude population, respectively. Females were significantly larger than males in both populations, due to greater age in both the highand low-altitude sites. Body size of either males or females did not differ significantly between populations; only males showed increased body size at the high-altitude site when age effect was statistically controlled for. The increased cline of male body size may be attributable to delayed maturation of the sex due to a shorter growing season at high altitudes.
Phylogeny and species differentiation of Mollitrichosiphum spp. (Aphididae, Greenideinae) based on mitochondrial COI and Cyt b genes
Authors: Zhang Ruiling , Huang Xiaolei , Jiang Liyun , Qiao Gexia
Published: February 2016

Phylogenetic analyses based on mitochondrial genes were conducted to reconstruct species relationships within the aphid genus Mollitrichosiphum (Aphididae, Greenideinae). MP and Bayesian analysis results using COI and Cyt b datasets, and combined MP, ML and Bayesian analysis of both were consistent with a morphologically supported monophyly. Subdivision of the genus into two subgenera was strongly supported. Samples of each included species form monophyletic clade, respectively; and the result implied the valid status of related species in this genus. These results suggest some surprising hypotheses regarding the phylogeography of the genus: the uplift of the Tibetan Plateau, reorganization of major river catchments and the isolation of Hainan Island were probably important factors contributing to the diversification of species in this genus.
A functional paradigm for evaluating culture: An example with cetaceans
Authors: Greggor Alison Linda
Published: February 2016

Nonhuman culture was first considered in nonhuman primates because they are genetically similar to humans. However, evolution is not progressive and therefore many species may occupy niches that favor socially transmitted, group specific behavior. Not surprisingly, evidence for culture has accrued in several taxonomic groups, including cetaceans. If culture is an adaptation, it is imperative we understand the factors that favor its formation. Understanding the evolutionary origin of culture will allow for a wider range of species to be studied, including those that are difficult to test in the laboratory. I propose a broad-based functional paradigm for evaluating nonhuman culture; based on the idea that while not all cultural behaviors may garner fitness benefits to the individual, the ecological and social environments in which cultural behaviors evolved must have favored the physical attributes and social learning capabilities that allow for cultural formation. Specifically this framework emphasizes the relationships between social learning, ecology, social systems, and biology in relation to culture. I illustrate the utility of the functional paradigm with evidence from the ceteacean group, while setting the stage for a stringent species by species analysis. By means of contextualizing culture, the Functional Paradigm can evaluate a species’ potential to exhibit culture and can investigate potentially cultural behaviors [Current Zoology 58 (2): 271–286, 2012].
Ontogenetic shift in response to prey-derived chemical cues in prairie rattlesnakes Crotalus viridis viridis
Authors: Saviola Anthony J. , Chiszar David , Mackessy Stephen P.
Published: February 2016

Snakes often have specialized diets that undergo a shift from one prey type to another depending on the life stage of the snake. Crotalus viridis viridis (prairie rattlesnake) takes different prey at different life stages, and neonates typically prey on ectotherms, while adults feed almost entirely on small endotherms. We hypothesized that elevated rates of tongue flicking to chemical stimuli should correlate with particular prey consumed, and that this response shifts from one prey type to another as individuals age. To examine if an ontogenetic shift in response to chemical cues occurred, we recorded the rate of tongue flicking for 25 neonate, 20 subadult, and 20 adult (average SVL = 280.9, 552, 789.5 mm, respectively) wild-caught C. v. viridis to chemical stimuli presented on a cotton-tipped applicator; water-soluble cues from two ectotherms (prairie lizard, Sceloporus undulatus, and house gecko, Hemidactylus frenatus), two endotherms (deer mouse, Peromyscus maniculatus and lab mouse, Mus musculus), and water controls were used. Neonates tongue flicked significantly more to chemical cues of their common prey, S. undulatus, than to all other chemical cues; however, the response to this lizard’s chemical cues decreased in adult rattlesnakes. Subadults tongue flicked with a higher rate of tongue flicking to both S. undulatus and P. maniculatus than to all other treatments, and adults tongue flicked significantly more to P. maniculatus than to all other chemical cues. In addition, all three sub-classes demonstrated a greater response for natural prey chemical cues over chemical stimuli of prey not encountered in the wild (M. musculus and H. frenatus). This shift in chemosensory response correlated with the previously described ontogenetic shifts in C. v. viridis diet. Because many vipers show a similar ontogenetic shift in diet and venom composition, we suggest that this shift in prey cue discrimination is likely a general phenomenon among viperid snakes.
Differentially-expressed opsin genes identified in Sinocyclocheilus cavefish endemic to China
Authors: Meng Fanwei , Zhao Yahui , Postlethwait John H. , Zhang Chunguang
Published: February 2016

Eye degeneration is a common troglomorphic character of cave-dwelling organisms. Comparing the morphology and molecular biology of cave species and their close surface relatives is a powerful tool for studying regressive eye evolution and other adaptive phenotypes. We compared two co-occurring and closely-related species of the fish genus Sinocyclocheilus, which is endemic to China and includes both surfaceand cave-dwelling species. Sinocyclocheilus tileihornes, a cave species, had smaller eyes than Sinocyclocheilus angustiporus, a surface species. Histological and immunohistochemical analyses revealed that the cavefish had shorter cones and more disorderly rods than did the surface-dwelling species. Using quantitative PCR and in situ hybridization, we found that rhodopsin and a long-wavelength sensitive opsin had significantly lower expression levels in the cavefish. Furthermore, one of two short-wavelength-sensitive opsins was expressed at significantly higher levels in the cavefish. Changes in the expression of opsin genes may have played a role in the degeneration of cavefish eyes.
The significance of midsummer movements of Autographa gamma: Implications for a mechanistic understanding of orientation behavior in a migrant moth
Authors: Chapman Jason W. , Lim Ka S. , Reynolds Don R.
Published: February 2016

The silver Y moth Autographa gamma undertakes windborne spring and fall migrations between winter breeding regions around the Mediterranean and summer breeding regions in northern Europe. Flight behaviors facilitating these migrations include: (i) selection of seasonally-favorable tailwinds; (ii) flying at the altitude of the fastest winds; (iii) adopting flight headings that partially counteract crosswind drift; and (iv) seasonal reversal of preferred directions between spring and fall. In the UK, radar measurements indicate that migratory activity is pronounced during the spring and fall, but is usually very low during midsummer (July). However, an atypically intense period of high-altitude flight was recorded during July 2006, and in this study we compare the flight behavior of A. gamma during these midsummer movements with the more typical spring and fall migrations. During July 2006, activity was most intense at significantly lower altitudes than occurred in spring or fall, and was not associated with the height of the fastest winds; consequently displacement speeds were significantly slower. The most striking difference was an absence of tailwind selectivity in July with windborne movements occurring on almost every night of the month and on tailwinds from all directions. Finally, orientation behavior was quantitatively different during July, with significantly greater dispersion of flight headings and displacements than observed in spring and fall. We discuss mechamsms which could have caused these differences, and conclude that a lack of appropriate photoperiod cues during development of the summer generation resulted in randomly-oriented ‘dispersive’ movements that were strikingly different from typical seasonal migrations.
Predicting ecological regime shift under climate change: New modelling techniques and potential of molecular-based approaches
Authors: Stafford Richard , Smith V. Anne , Husmeier Dirk , Grima Thomas , Guinn Barbara-ann
Published: February 2016

Ecological regime shift is the rapid transition from one stable community structure to another, often ecologically inferior, stable community. Such regime shifts are especially common in shallow marine communities, such as the transition of kelp forests to algal turfs that harbour far lower biodiversity. Stable regimes in communities are a result of balanced interactions between species, and predicting new regimes therefore requires an evaluation of new species interactions, as well as the resilience of the ‘stable’ position. While computational optimisation techniques can predict new potential regimes, predicting the most likely community state of the various options produced is currently educated guess work. In this study we integrate a stable regime optimisation approach with a Bayesian network used to infer prior knowledge of the likely stress of climate change (or, in practice, any other disturbance) on each component species of a representative rocky shore community model. Combining the results, by calculating the product of the match between resilient computational predictions and the posterior probabilities of the Bayesian network, gives a refined set of model predictors, and demonstrates the use of the process in determining community changes, as might occur through processes such as climate change. To inform Bayesian priors, we conduct a review of molecular approaches applied to the analysis of the transcriptome of rocky shore organisms, and show how such an approach could be linked to meas-ureable stress variables in the field. Hence species-specific microarrays could be designed as biomarkers of in situ stress, and used to inform predictive modelling approaches such as those described here.
Daily shoaling patterns in the zebrafish Danio rerio
Authors: Paciorek Timothy , Mcrobert Scott
Published: February 2016

Shoaling intensity in zebrafish Danio rerio is believed to vary throughout subjective day and night hours. This experiment examines long term variations in shoaling behavior. Adult zebrafish Danio rerio were maintained under a 12:12 LD cycle (with dim red light serving as reduced visibility during subjective dark hours), and their shoaling behavior was monitored every hour for a three-day period of time. Our results show that zebrafish perform shoaling behavior throughout subjective day and under reduced visibility conditions, although mean shoaling times during the light phase were significantly higher than mean shoaling times during the dark phase. However, on the 3rd day of the experiment, mean shoaling times during the subjective night had increased and mean shoaling times during the subjective day had decreased. This shift in intensity was not seen on the first two days of the study, and may represent the influence of experience on the behavior of the test fish. We believe this study shows that shoaling behavior changes with light/dark cycles and that fish shoal even during reduced visibility conditions.
Species diversification and phylogeographical patterns of birds in response to the uplift of the Qinghai-Tibet Plateau and Quaternary glaciations
Authors: Lei Fumin , Qu Yanhua , Song Gang
Published: February 2016

The Qinghai-Tibet Plateau (QTP) is well known for being of great importance in the evolution of montane species due to its unique geological history and landform configuration, climate complexity, and diversified habitats. The effect of environmental changes since the Quaternary on species diversification, population genetic structure, and demography under environmental change can be studied using phylogenetic and phylogeographical approaches. Birds are the most well-studied group of all terrestrial vertebrates with regard to their response to climatic changes over time. Herein, we briefly review the species diversification of birds in response to the uplift of the QTP, focusing on summarizing the different phylogeographical patterns of birds on the Plateau, its southeastern margin, and the Eastern Himalayas and the reasons underlying these patterns. Speciation was found to be closely related to the uplift of the QTP, with different patterns of intraspecific processes: (1) no divergence within a single refuge was identified in a restricted semi-continuous area of the eastern margin of the Plateau; (2) two divergent lineages with separated refugia were located at the south-eastern and north-eastern margins of the plateau; and (3) multiple divergent lineages within subregions were found in the Eastern Himalayas. Glacial movements and induced climate change are considered to be key factors in shaping these different patterns. The species distributed mainly in the heavily ice-covered platform regions of the Plateau experienced population expansion following the retreat of the extensive glaciations, whereas the species distributed on the ice-free edges of the plateau maintained their population size at a stable level. Demographic stresses on the edge species might have been mitigated by the milder climate in comparison to their platform-distributed counterparts. Various behavioral and ecological characteristics, including dispersal capacity, habitat preference, and elevation specificity, along with evolutionary history might have helped to shape these different phylogeographical patterns.
Phenology of high-arctic butterflies and their floral resources: Species-specific responses to climate change
Authors: Høye Toke T. , Eskildsen Anne , Hansen Rikke R. , Bowden Joseph J. , Schmidt Niels M. , Kissling W. Daniel
Published: February 2016

Current global warming is particularly pronounced in the Arctic and arthropods are expected to respond rapidly to these changes. Long-term studies of individual arthropod species from the Arctic are, however, virtually absent. We examined butterfly specimens collected from yellow pitfall traps over 14 years (1996–2009) at Zackenberg in high-arctic, north-east Greenland. Specimens were previously sorted to the family level. We identified them to the species level and examined long-term species-specific phenological responses to recent summer warming. Two species were rare in the samples (Polaris fritillary Bolo-ria polaris and Arctic blue Plebejus glandon) and statistical analyses of phenological responses were therefore restricted to the two most abundant species (Arctic fritillary, B. chariclea and Northern clouded yellow Colias hecla). Our analyses demonstrated a trend towards earlier flight seasons in B. chariclea, but not in C. hecla. The timing of onset, peak and end of the flight season in B. chariclea were closely related to snowmelt, July temperature and their interaction, whereas onset, peak and end of the flight season in C. hecla were only related to timing of snowmelt. The duration of the butterfly flight season was significantly positively related to the temporal overlap with floral resources in both butterfly species. We further demonstrate that yellow pitfall traps are a useful alternative to transect walks for butterfly recording in tundra habitats. More phenological studies of Arctic arthropods should be carried out at the species level and ideally be analysed in context with interacting species to assess how ongoing climate change will affect Arctic biodiversity in the near future.
Rufous-and-white wrens Thryophilus rufalbus do not exhibit a dear enemy effects towards conspecific or heterospecific competitors
Authors: Battiston Matthew M. , Wilson David R. , Graham Brendan A. , Kovach Kristin A. , Mennill Daniel J.
Published: February 2016

Many territorial animals exhibit reduced aggression towards neighbours. Known as “the dear enemy effect”, this phenomenon has been documented among conspecific animals across a wide range of animal taxa. In theory, the dear enemy effect can also exist between individuals of different species, particularly when those species compete for shared resources. To date, a heterospecific dear enemy effects has only been documented in ants. In this study, we test for both a conspecific and heterospe-cific dear enemy effect in neotropical rufous-and-white wrens Thryophilus rufalbus. This species competes for resources with banded wrens Thryophilus pleurostictus, a closely related sympatric congener. We used acoustic playback to simulate ruf-ous-and-white wren and banded wren neighbours and non-neighbours at the edges of rufous-and-white wren territories. Ruf-ous-and-white wrens responded more strongly to signals from their own species, demonstrating that resident males discriminate between conspecific and heterospecific rivals. They did not, however, exhibit a conspecific dear enemy effect. Further, they did not exhibit a heterospecific dear enemy effect. This could be due to neighbours and non-neighbours posing similar levels of threat in this system, to the possibility that playback from the edges of the subjects’ large territories did not simulate a threatening signal, or to other factors. Our study provides the first test of a heterospecific dear enemy effect in vertebrates, and presents a valuable experimental approach for testing for a heterospecific dear enemy effect in other animals.
Natal dispersal in a social landscape: Considering individual behavioral phenotypes and social environment in dispersal ecology
Authors: Wey Tina W. , Spiegel Orr , Montiglio Pierre-Olivier , Mabry Karen E.
Published: February 2016

Natal dispersal, the movement of an organism from its birthplace to the site of first reproduction, is fundamental to many ecological and evolutionary processes. Mechanistically, individual dispersal decisions can depend on both individual phenotype and environmental cues. In particular, many established evolutionary theories of dispersal highlight the importance of the social environment. More recent research in behavioral ecology has focused on the importance of individual behavioral phenotypes. We reviewed the literature on individual behavioral phenotypes and dispersal and suggest that how individual behavioral phenotypes interact with the immediate social environment experienced by individuals in influencing dispersal is still poorly understood, despite growing interest. We found that very few studies had examined the interaction of individual behavioral phenotypes and social factors, and behavioral phenotypes related to social tendencies were less commonly measured than were behavioral phenotypes related to exploration or response to risk. Further, and unsurprisingly, studies on social behavioral phenotypes and dispersal behaviors during the transience stage of dispersal were underrepresented compared to the departure or settlement stages. Future studies in this area should aim to: a) make explicit links between behavioral traits and their proposed effects on dispersal decisions throughout multiple stages of dispersal, b) integrate more continuous dispersal variables, and c) consider the effects of the spatial distribution and phenotypes of conspecifics (i.e., the social landscape) encountered by individual dispersers.
Preinjury Aerobic Fitness Predicts Postoperative Outcome and Activity Level After Acetabular Fracture Fixation
Authors: Phruetthiphat Ong-art , Koehler Daniel M. , Karam Matthew D. , Rungprai Chamnanni , Gao Yubo , Marsh J. Lawrence
Published: February 2016

Objectives:

To investigate whether aerobic fitness as determined by preoperative metabolic equivalents (METS) better predicts postoperative functional outcomes after open reduction and internal fixation (ORIF) of acetabular fractures than chronologic age.

Design:

Retrospective review.

Setting:

Level 1 Trauma Center.

Patients/Participants:

A total of 157 patients underwent open surgical treatment for acetabular fracture between January 2005 and December 2013 with age ≥18 years and minimum 1-year follow-up inclusive of imaging, functional outcome scores, and complications.

Intervention:

ORIF of acetabular fracture.

Main Outcome Measurements:

Final postoperative functional outcomes as assessed with the University of California Los Angeles activity score and the Western Ontario and McMaster Universities Osteoarthritis Index.

Results:

Multivariate logistic regression analysis demonstrated elevated preinjury METS, female gender, and lower injury severity score (<18) to be significant independent factors predictive of improved functional outcome per the University of California Los Angeles score. Similarly, preinjury METS were identified as significant predictors for improved Western Ontario and McMaster Universities Osteoarthritis Index scores for both the stiffness and physical function components. Chronologic age was not a significant predictor for any functional outcome score. Furthermore, a Pearson correlation analysis demonstrated a weak relationship between preoperative METS and chronologic age (r = −0.346).

Conclusions:

Pre-operative aerobic fitness as determined by METS may prove to be a superior prognostic factor for predicting postoperative functional outcome after acetabular fracture fixation than chronologic age. Consideration of aerobic fitness, in addition to other established prognostic factors, may be useful to patients and surgeons for injury counseling purposes.

Level of Evidence:

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Succession in the family business: drivers and pathways
Authors: Bizri Rima
Published: February 2016

Purpose

– The succession process represents one of the most critical events in the family business lifecycle. The purpose of this paper is to explore this process while focussing first on the drivers behind the choice of successor and, second, on the impact of this choice on the entrepreneurial behavior of the siblings.

Design/methodology/approach

– The qualitative approach was used in which multiple case analyses were performed. A total of 12 cases were purposively selected from the Lebanese private sector, and semi-structured interviews were conducted with the successors and the founders when available. The interview data were transcribed and a coding scheme was created to generate relevant categories. Those categories were named and later re-assessed by an external researcher to ensure inter-rater reliability.

Findings

– The three dimensions of social capital were found to have a profound influence on the succession decision with much focus on familial stewardship as an emerging cognitive driving force. When “familial stewardship” is shared by incumbent and sibling, it strengthens the latter’s chances of being chosen as successor. Further, a succession pathways model was introduced that depicts the siblings’ behavior following the succession decision which seems to often trigger further entrepreneurship.

Originality/value

– This study is distinct as it introduces a new cognitive construct that helps rationalize the successor-selection decision in a Middle Eastern context. It also goes beyond the succession event to depict potential entrepreneurial behavior triggered by succession.
The tangled web of mobile telecommunication mergers: Hutchison Whampoa, Telefónica and BT
Authors: Curwen Peter , Whalley Jason
Published: February 2016

Purpose

– This paper aims to demonstrate how consolidation within Europe’s mobile telecommunication markets requires willing buyers and sellers.

Design/methodology/approach

– After highlighting the resurgence in merger and acquisition (M
&
A) activity in mobile telecommunications, the paper draws on a variety of secondary sources to analyse the strategies of three companies.

Findings

– The paper highlights the interwoven nature of the strategies of three companies: BT, Hutchison Whampoa and Telefónica. BT has returned to the mobile telecommunications market in the UK, with the company it did not acquire being purchased by Hutchison. As Hutchison implements a “double or quits” strategy in Europe, it has acquired operations from Telefónica, which, in turn, has exited most of its non-Spanish European operations to focus on Latin America.

Research limitations/implications

– The paper relies on secondary data and thus highlights the challenges of doing so and the need for more information regarding M
&
As to be in the public domain.

Practical implications

– There is a need to adopt a sector-wide or regional approach for analysing the strategies of telecommunication companies.

Originality/value

– The paper uniquely provides an overview of three corporate strategies to show how they interact with one another.
Flavor and Functional Characteristics of Whey Protein Isolates from Different Whey Sources
Authors: Smith T.J. , Foegeding E.A. , Drake M.A.
Published: February 2016

This study evaluated flavor and functional characteristics of whey protein isolates (WPIs) from Cheddar, Mozzarella, Cottage cheese, and rennet casein whey. WPIs were manufactured in triplicate. Powders were rehydrated and evaluated in duplicate by descriptive sensory analysis. Volatile compounds were extracted by solid‐phase microextraction followed by gas chromatography‐mass spectrometry. Functional properties were evaluated by measurement of foam stability, heat stability, and protein solubility. WPI from Cheddar and Cottage cheese whey had the highest cardboard flavor, whereas sweet aromatic flavor was highest in Mozzarella WPI, and rennet casein WPI had the lowest overall flavor and aroma. Distinct sour taste and brothy/potato flavor were also noted in WPI from Cottage cheese whey. Consistent with sensory results, aldehyde concentrations were also highest in Cheddar and Cottage cheese WPI. Overrun, yield stress, and foam stability were not different (P > 0.05) among Cheddar, Mozzarella, and rennet casein WPI, but WPI foams from Cottage cheese whey had a lower overrun and air‐phase fraction (P < 0.05). Cottage cheese WPI was more heat stable at pH 7 (P < 0.05) than other WPI in 4% protein solutions, and was the only WPI to not gel at 10% protein. Cottage cheese WPI was less soluble at pH 4.6 compared to other WPI (P < 0.05) and also exhibited higher turbidity loss at pH 3 to 7 compared to other WPI (P < 0.05). This study suggests that WPI produced from nontraditional whey sources could be used in new applications due to distinct functional and flavor characteristics.
Antibiotic Resistance Patterns of Gram‐Negative Psychrotrophic Bacteria from Bulk Tank Milk
Authors: Decimo Marilù , Silvetti Tiziana , Brasca Milena
Published: February 2016

Bacterial resistance to antibiotics is a major global health problem and resistance of Pseudomonadaceae and Enterobacteriaceae is a serious concern. We investigated the prevalence of drug‐resistance in a total of 80 psychrotrophic strains from bulk milk belonging to Pseudomonas genus (n. 63) and Enterobacteriaceae group (n. 17). All the strains were tested against 16 antibiotics. Pseudomonas were further investigated for their sensitivity against 12 additional antibiotics. Pseudomonas showed a high susceptibility toward fluoroquinolones, aminoglycosides, and piperacillin and, to a lesser extent, to imipenem, ceftazidime, cefepime. Thirty‐five out of 63 Pseudomonas strains were susceptible to meropenem, while among antibiotics for which recommended breakpoints are not yet available, 55% of Pseudomonas strains had no inhibition halo in presence of nitrofurantoin, highlighting a resistance toward this drug. The results obtained in this study indicate a high efficiency of fluoroquinolones, chloramphenicol (94%), and kanamycin (76%) for Enterobacteriaceae while a high prevalence of resistant strains was found to ampicillin (13/17). Serratia marcescens is highly susceptible to fluoroquinolones, chloramphenicol, and kanamycin. Moreover, mupirocin seems to be the new antibiotic with the less efficacy for Enterobacteriaceae, with 41% of strains without halo, pointing out an important resistance. Further knowledge on resistance to known and new antibiotics among Pseudomonas species and Enterobacteriaceae of milk origin was acquired.
Antecedents of cerebral palsy according to severity of motor impairment
Authors: Ahlin Kristina , Himmelmann Kate , Nilsson Staffan , Sengpiel Verena , Jacobsson Bo
Published: February 2016

Introduction

The purpose of this study was to determine whether antecedents and neuroimaging patterns vary according to the severity of motor impairment in children with cerebral palsy.

Material and methods

A population‐based study in which all 309 term‐born children with spastic and dyskinetic cerebral palsy born between 1983 and 1994 and 618 matched controls were studied. Antecedents were retrieved from obstetric records. Information on neuroimaging was retrieved from the cerebral palsy Register of Western Sweden. Cases were grouped by severity of motor impairment: mild (walks without aids), moderate (walks with aids) or severe (dependent on wheelchair). Binary logistic regression, the Cochran–Armitage test for trends, interaction analyses and interrelationship analyses were performed.

Results

Antecedents associated with mild motor impairment were antepartum (placental weight, maternal weight and antibiotic therapy) or intrapartum and postpartum adverse events (meconium‐stained amniotic fluid, low Apgar score, admission to neonatal intensive care unit and neonatal encephalopathy). Antecedents associated with severe motor impairment were antepartum (congenital infection, small head circumference and brain maldevelopment) or intrapartum and postpartum (emergency cesarean section and maternal antibiotic therapy). Comparisons between mild and severe motor impairment revealed congenital infection, maldevelopment, neonatal encephalopathy and meconium aspiration syndrome significantly more often in the group with severe motor impairment (p < 0.05). White matter injury was the most common neuroimaging pattern in mild motor impairment, whereas maldevelopment and cortical/subcortical lesions were most common in the severe motor impairment group.

Conclusions

Our results suggest a variation in antecedents associated with cerebral palsy, related to severity of motor impairment. Timing of antecedents corresponded to neuroimaging patterns.
Long‐term facilitation of expiratory and sympathetic activities following acute intermittent hypoxia in rats
Authors: Lemes E. V. , Aiko S. , Orbem C. B. , Formentin C. , Bassi M. , Colombari E. , Zoccal D. B.
Published: February 2016

Aim

Acute intermittent hypoxia (AIH) promotes persistent increases in ventilation and sympathetic activity, referred as long‐term facilitation (LTF). Augmented inspiratory activity is suggested as a major component of respiratory LTF. In this study, we hypothesized that AIH also elicits a sustained increase in expiratory motor activity. We also investigated whether the expiratory LTF contributes to the development of sympathetic LTF after AIH.

Methods

Rats were exposed to AIH (10 × 6–7% O2 for 45 s, every 5 min), and the cardiorespiratory parameters were evaluated during 60 min using in vivo and in situ approaches.

Results

In unanesthetized conditions (n = 9), AIH elicited a modest but sustained increase in baseline mean arterial pressure (MAP, 104 ± 2 vs. 111 ± 3 mmHg, P < 0.05) associated with enhanced sympathetic and respiratory‐related variabilities. In the in situ preparations (n = 9), AIH evoked LTF in phrenic (33 ± 12%), thoracic sympathetic (75 ± 25%) and abdominal nerve activities (69 ± 14%). The sympathetic overactivity after AIH was phase‐locked with the emergence of bursts in abdominal activity during the late‐expiratory phase. In anesthetized vagus‐intact animals, AIH increased baseline MAP (113 ± 3 vs. 122 ± 2 mmHg, P < 0.05) and abdominal muscle activity (535 ± 94%), which were eliminated after pharmacological inhibition of the retrotrapezoid nucleus/parafacial respiratory group (RTN/pFRG).

Conclusion

These findings indicate that increased expiratory activity is also an important component of AIH‐elicited respiratory LTF. Moreover, the development of sympathetic LTF after AIH is linked to the emergence of active expiratory pattern and depends on the integrity of the neurones of the RTN/pFRG.
Alcohol consumption at age 11–12 years and traumatic dental injuries at age 15–16 years in school children from East London
Authors: Baig Enver Muneera , Marcenes Wagner , Stansfeld Stephen A. , Bernabé Eduardo
Published: February 2016

Aim

To explore the association between alcohol consumption at age 11–12 years and traumatic dental injuries (TDI) at age 15–16 years.

Methods

Data of 635 adolescents who participated in phases I and III of the Research with East London Adolescents Community Health Survey (RELACHS), a longitudinal school‐based survey of a representative sample of adolescents from East London, were used for this study. Information on socio‐demographic characteristics and alcohol consumption was obtained from questionnaires in phase I when adolescents were 11–12 years of age. Data on TDI and clinical characteristics (incisor overjet and lip coverage) were taken from clinical examination in phase III when adolescents were 15–16 years of age. The association between (lifetime and last month) alcohol consumption and TDI was assessed in crude and adjusted logistic regression models.

Results

Overall, 14.5% of adolescents had ever consumed alcohol and 3.5% had consumed alcohol the month before the baseline survey, whereas 17% of adolescents had experienced TDI by age 15–16 years. No significant association of alcohol consumption with TDI was seen in these adolescents for either lifetime (adjusted odds ratio [OR]: 0.87; 95% confidence interval [CI]: 0.45–1.67) or last month consumption of alcohol (adjusted OR: 0.86; 95% CI: 0.28–2.69).

Conclusion

This study did not support the association between alcohol use and TDI in adolescents.
A comparison of survival in patients with hepatocellular carcinoma and portal vein invasion treated by radioembolization or sorafenib
Authors: de la Torre Manuel A. , Buades‐Mateu Juan , de la Rosa Pedro A. , Lué Alberto , Bustamante Francisco J. , Serrano María T. , Testillano Milagros , Lorente Sara , Arenas Juan I. , Gil Cristina , Iñarrairaegui Mercedes , Sangro Bruno
Published: February 2016

Background & Aims

Sorafenib (SOR) is the standard of care for patients with hepatocellular carcinoma (HCC) and portal vein invasion (PVI), based on the results of phase 3 trials. However, radioembolization (RE) using yttrium‐90 microspheres has been shown to achieve higher response rates and better survival in large cohorts and phase 2 trials. This study aimed to compare survival of HCC patients with PVI treated by RE or SOR.

Methods

Survival among patients with HCC and PVI treated with RE or SOR in four Spanish hospitals between 2005 and 2013 was analysed retrospectively. Kaplan–Meier survival curves were plotted and baseline variables tested for prognostic value using the log‐rank test. A multivariate prognostic model including variables identified in the univariate analysis and adjusted by a propensity score based on factors that may determine the probability of exposure to RE was generated using Cox regression analyses.

Results

After a median follow‐up of 6 months, 60 deaths had occurred: 38 and 22 in SOR and RE groups respectively. Median survival was 6.7 months (95%CI 5.2–8.1 months) for the entire cohort, and 8.8 months (95%CI 1.8–15.8) in the RE group and 5.4 months (95%CI 2.7–8.1) in the SOR group (P = 0.047). The difference in survival was still statistically significant when 13 patients in the RE group who started SOR after a median time of 8 months were censored from the analysis.

Conclusions

In a cohort of patients with HCC and PVI treatment with RE was associated with a more prolonged survival compared with SOR.
A new computer aided diagnosis system for evaluation of chronic liver disease with ultrasound shear wave elastography imaging
Authors: Gatos Ilias , Tsantis Stavros , Spiliopoulos Stavros , Karnabatidis Dimitris , Theotokas Ioannis , Zoumpoulis Pavlos , Loupas Thanasis , Hazle John D. , Kagadis George C.
Published: February 2016

Purpose:

Classify chronic liver disease (CLD) from ultrasound shear‐wave elastography (SWE) imaging by means of a computer aided diagnosis (CAD) system.

Methods:

The proposed algorithm employs an inverse mapping technique (red‐green‐blue to stiffness) to quantify 85 SWE images (54 healthy and 31 with CLD). Texture analysis is then applied involving the automatic calculation of 330 first and second order textural features from every transformed stiffness value map to determine functional features that characterize liver elasticity and describe liver condition for all available stages. Consequently, a stepwise regression analysis feature selection procedure is utilized toward a reduced feature subset that is fed into the support vector machines (SVMs) classification algorithm in the design of the CAD system.

Results:

With regard to the mapping procedure accuracy, the stiffness map values had an average difference of 0.01 ± 0.001 kPa compared to the quantification results derived from the color‐box provided by the built‐in software of the ultrasound system. Highest classification accuracy from the SVM model was 87.0% with sensitivity and specificity values of 83.3% and 89.1%, respectively. Receiver operating characteristic curves analysis gave an area under the curve value of 0.85 with [0.77–0.89] confidence interval.

Conclusions:

The proposed CAD system employing color to stiffness mapping and classification algorithms offered superior results, comparing the already published clinical studies. It could prove to be of value to physicians improving the diagnostic accuracy of CLD and can be employed as a second opinion tool for avoiding unnecessary invasive procedures.
An aromatic ion platform for enantioselective Brønsted acid catalysis
Authors: Gheewala Chirag D. , Collins Bridget E. , Lambert Tristan H.
Published: February 2016

Competition for binaphthyl catalysts

The binaphthyl framework has proven extremely effective in biasing a broad range of chemical reactions toward just one of two mirror-image products. The motif was first applied as a ligand in metal catalysis, and more recently as a conjugate base in acid catalysis. Gheewala
et al.
report a class of chiral carbon acids based around a cyclopentadiene framework that are easily accessible from readily available precursors. The compounds are showcased as highly selective catalysts for asymmetric Mukaiyama Mannich and oxocarbenium aldol reactions.

Science
, this issue p.
961
Saving freshwater from salts
Authors: Cañedo-Argüelles M. , Hawkins C. P. , Kefford B. J. , Schäfer R. B. , Dyack B. J. , Brucet S. , Buchwalter D. , Dunlop J. , Frör O. , Lazorchak J. , Coring E. , Fernandez H. R. , Goodfellow W. , Achem A. L. González , Hatfield-Dodds S. , Karimov B. K. , Mensah P. , Olson J. R. , Piscart C. , Prat N. , Ponsá S. , Schulz C.-J. , Timpano A. J.
Published: February 2016

Ion-specific standards are needed to protect biodiversity
Response to Comment on “Abrupt warming events drove Late Pleistocene Holarctic megafaunal turnover”
Authors: Cooper Alan , Turney Chris , Hughen Konrad
Published: February 2016

Rasmussen and Svensson correctly point out that there is currently no satisfactory method to fully align the Greenland and Cariaco Basin records of climate change. However, our approach using interstadial onsets as tie-points allows direct comparison between radiocarbon dates and Greenland climate records. Crucially, both the standard Greenland and the merged Greenland-Cariaco time scales show that interstadial warming was associated with megafaunal genetic transitions.
Site-resolved imaging of a fermionic Mott insulator
Authors: Greif Daniel , Parsons Maxwell F. , Mazurenko Anton , Chiu Christie S. , Blatt Sebastian , Huber Florian , Ji Geoffrey , Greiner Markus
Published: February 2016

Watching fermions transition on site

Optical lattices are a promising platform for simulating the many-body physics that occurs in solids. In lattices filled with cold bosonic atoms, “quantum microscopy” makes it possible to watch quantum phase transitions as they unravel. Greif
et al.
bring a similar capability to lattices filled with fermions, which are trickier to cool but are a closer match to electrons in a solid. Tuning the interaction between the
6
Li atoms allowed for the observation of transitions from a metallic phase to a band insulator and then to an interaction-dominated Mott insulator phase.

Science
, this issue p.
953
How do you like your tap water?
Authors: Rosario-Ortiz Fernando , Rose Joan , Speight Vanessa , Gunten Urs von , Schnoor Jerald
Published: February 2016

Safe drinking water may not need to contain a residual disinfectant
Predictability of Phenotype in Relation to Common β-Lactam Resistance Mechanisms in Escherichia coli and Klebsiella pneumoniae
Authors: Agyekum Alex , Fajardo-Lubián Alicia , Ai Xiaoman , Ginn Andrew N. , Zong Zhiyong , Guo Xuejun , Turnidge John , Partridge Sally R. , Iredell Jonathan R.
Published: February 2016

The minimal concentration of antibiotic required to inhibit the growth of different isolates of a given species with no acquired resistance mechanisms has a normal distribution. We have previously shown that the presence or absence of transmissible antibiotic resistance genes has excellent predictive power for phenotype. In this study, we analyzed the distribution of six β-lactam antibiotic susceptibility phenotypes associated with commonly acquired resistance genes in
Enterobacteriaceae
in Sydney, Australia.
Escherichia coli
(
n
= 200) and
Klebsiella pneumoniae
(
n
= 178) clinical isolates, with relevant transmissible resistance genes (
bla
TEM
,
n
= 33; plasmid AmpC,
n
= 69; extended-spectrum β-lactamase [ESBL],
n
= 116; and carbapenemase,
n
= 100), were characterized. A group of 60 isolates with no phenotypic resistance to any antibiotics tested and carrying none of the important β-lactamase genes served as comparators. The MICs for all drug-bacterium combinations had a normal distribution, varying only in the presence of additional genes relevant to the phenotype or, for ertapenem resistance in
K. pneumoniae
, with a loss or change in the outer membrane porin protein OmpK36. We demonstrated mutations in
ompK36
or absence of OmpK36 in all isolates in which reduced susceptibility to ertapenem (MIC, >1 mg/liter) was evident. Ertapenem nonsusceptibility in
K. pneumoniae
was most common in the context of an OmpK36 variant with an ESBL or AmpC gene. Surveillance strategies to define appropriate antimicrobial therapies should include genotype-phenotype relationships for all major transmissible resistance genes and the characterization of mutations in relevant porins in organisms, like
K. pneumoniae
.
Diagnosis of Clostridium difficile Infections in Children
Authors: Antonara Stella , Leber Amy L.
Published: February 2016

The detection and diagnosis of
Clostridium difficile
infection in pediatric populations have some unique considerations in comparison to testing in adults. The testing methodologies, including toxigenic culture, cell cytotoxicity, antigen detection, and, more recently, molecular testing, are the same in all age groups. However, limited data exist on the specific performance characteristics in children. In this review, we focus on the challenges of testing in pediatric populations and assess the available data on test performance in these populations. Additionally, a review of the existing guidance for testing is provided.