bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of social anxiety on recognition memory for happy and angry faces: Comparison between own- and other-race faces
Authors: Kikutani Mariko
Published: March 2017

The reported experiment investigated memory of unfamiliar faces and how it is influenced by race, facial expression, direction of gaze and observers’ level of social anxiety. In total, 87 Japanese participants initially memorized images of Oriental and Caucasian faces displaying either happy or angry expressions with direct or averted gaze. They then saw the previously seen faces and additional distractor faces displaying neutral expressions and judged whether they had seen them before. Their level of social anxiety was measured with a questionnaire. Regardless of gaze or race of the faces, recognition for faces studied with happy expressions was more accurate than for those studied with angry expressions (happiness advantage), but this tendency weakened for people with higher levels of social anxiety, possibly due to their increased anxiety for positive feedback regarding social interactions. Interestingly, the reduction in the happiness advantage observed for the highly anxious participants was more prominent for the own-race faces than for the other-race faces. The results suggest that angry expression disrupts processing of identity-relevant features of the faces, but the memory for happy faces is affected by the social anxiety traits, and the magnitude of the impact may depend on the importance of the face.
How does the welfare state model influence social political attitudes? An analysis of citizens' concrete and abstract attitudes toward poverty
Authors: Toikko Timo , Rantanen Teemu
Published: March 2017

This study examines the relationship between the welfare state models and social political attitudes. The data are based on the sixth round of the European Social Survey. The study revealed a mechanism of how the relationship between concrete and abstract attitudes differs between the welfare states. In the Anglo-Saxon and Nordic welfare states the relationship is a positive one, which indicates that the welfare state has a broad support among citizens. In the Continental, Eastern and Southern welfare states the relationship is a negative one. This means that the less satisfied citizens are with governmental measures, the more positive their attitudes are regarding protecting citizens against poverty. Also the study showed that the welfare state model directly influences citizens’ concrete attitudes and indirectly influences abstract poverty attitudes. In this sense, the welfare state model is seen more as an attitudinal perception than an actual social policy.
Wave interactions and stability of the Riemann solution for a strictly hyperbolic system of conservation laws
Authors: Sen Anupam , Raja Sekhar T. , Sharma V.
Published: March 2017

In this article, we study the interaction of delta shock waves for the one-dimensional strictly hyperbolic system of conservation laws with split delta function. We prove that Riemann solutions are stable under local small perturbations of the Riemann initial data. The global structure and large time asymptotic behaviour of the perturbed Riemann solutions are constructed and analyzed case by case.
Deubiquitinating enzymes Ubp2 and Ubp15 regulate endocytosis by limiting ubiquitination and degradation of ARTs
Authors: Ho Hsuan-Chung , MacGurn Jason A. , Emr Scott D.
Published: March 2017

Endocytic down-regulation of cell-surface proteins is a fundamental cellular process for cell survival and adaptation to environmental stimuli. Ubiquitination of cargo proteins serves as the sorting signal for downstream trafficking and relies on the arrestin-related trafficking adaptor (ART)-Rsp5 ubiquitin ligase adaptor network in yeast. Hence proper regulation of the abundance and activity of these ligase–adaptor complexes is critical for main­tenance of optimal plasma membrane protein composition. Here we report that the stability of ARTs is regulated by the deubiquitinating enzymes (DUBs) Ubp2 and Ubp15. By counteracting the E3 ubiquitin ligase Rsp5, Ubp2 and Ubp15 prevent hyperubiquitination and proteasomal degradation of ARTs. Specifically, we show that loss of both Ubp2 and Ubp15 results in a defect in Hxt6 endocytosis associated with Art4 instability. Our results uncover a novel function for DUBs in the endocytic pathway by which Ubp2 and Ubp15 positively regulate the ART-Rsp5 network.
Preliminary Study of Tirofiban Infusion in Coil Embolization of Ruptured Intracranial Aneurysms
Authors: Yoon Chang Hyo , Lee Ho-Won , Kim Young Soo , Lee Sang Won , Yeom Jeong A , Roh Jieun , Baik Seung Kug
Published: March 2017

BACKGROUND

There have been some reports on the use of intra-arterial tirofiban in ruptured intracranial aneurysms, but few studies have reported on the use of 24 h of intravenous tirofiban infusion in patients with subarachnoid hemorrhage.

OBJECTIVE

To present our experience with intravenous tirofiban infusion, in the form of a monotherapy as well as in addition to intra-arterial tirofiban, as a prophylactic, and as a rescue management for thrombus in patients who have undergone embolization with coils for ruptured intracranial aneurysms.

METHODS

Between December 2008 and January 2015, we retrospectively reviewed 249 ruptured intracranial aneurysms that were treated with coiling at our institutions. A total of 28 patients harboring 28 ruptured and 3 unruptured intracranial aneurysms underwent intravenous tirofiban infusion during or after coil embolization of an aneurysm. Intra-arterial infusion of tirofiban via a microcatheter was also performed in 26 patients.

RESULTS

Thromboembolic formation during the procedure was detected in 25 cases. Intra-arterial tirofiban dissolved the thromboembolus under angiographic control after 10 or more minutes in 19 (76%) of 25 patients. Two intracranial hemorrhagic complications (increase in the extent of hematoma) occurred during the follow-up period. Two cases of other complications occurred: hematuria and perioral bleeding.

CONCLUSION

Intravenous tirofiban, as a monotherapy or in addition to intra-arterial tirofiban for thrombotic complications, seems to be useful as a treatment for acute aneurysm. However, alternatives to tirofiban should be considered if an associated hematoma is discovered before a patient receives a tirofiban infusion.
Toward the full and proper implementation of Jordan's Principle: An elusive goal to date
Authors: Blackstock Cindy
Published: March 2017

First Nations children experience service delays, disruptions and denials due to jurisdictional payment disputes within and between federal and provincial/territorial governments. The House of Commons sought to ensure First Nations children could access government services on the same terms as other children when it unanimously passed a private members motion in support of Jordan's Principle in 2007. Jordan's Principle states that when a jurisdictional dispute arises regarding public services for a First Nations child that are otherwise available to other children, the government of first contact pays for the service and addresses payment disputes later. Unfortunately, the federal government adopted a definition of Jordan's Principle that was so narrow (complex medical needs with multiple service providers) that no child ever qualified. This narrow definition has been found to be unlawful by the Federal Court of Canada and the Canadian Human Rights Tribunal. The present commentary describes Jordan's Principle, the legal cases that have considered it and the implications of those decisions for health care providers.
Paediatric school-based clinics in Saskatoon: Providing equitable access to paediatric care
Authors: Mehtar Maryam
Published: March 2017

Paediatric school-based clinics (PSBCs) were established in Saskatoon (Saskatchewan) in 2007, to provide access to specialized paediatric health care as part of multidisciplinary and interdisciplinary teams, and alongside existing services. In its ninth year, the PSBCs have grown both in number and services offered, and in patient numbers – for both new patients and repeat follow-up visits. Viewing paediatric health consistently through the lens of the social determinants of health has been essential in delivering care, which require consideration and negotiation of these contexts in formulating management plans. The responsive relationships we continue to establish with our patients through the PSBCs have enabled us to work effectively with children and youth, and continue the growth of our successes.
Medical education, social responsibility and praxis: Responding to the needs of all children
Authors: Martimianakis Maria Athina
Published: March 2017

While poverty is a recognized risk factor for ill health, directly intervening on the effects of poverty has traditionally been considered to fall outside the realm of a physician's daily practice. Yet, to appropriately respond to the health needs of all children, we have the social responsibility to help our trainees become competent health advocates. Experiential learning approaches can be used to aid students in developing identities and competencies as health advocates. Experiencing illness outside the sterility of the clinic, from the patient's point of view, encourages students to seek the knowledge they need to care for patients who are disenfranchised, socially vulnerable and/or marginalized.
Impact of Acute Kidney Injury in Patients Hospitalized With Pneumonia
Authors: Chawla Lakhmir S. , Amdur Richard L. , Faselis Charles , Li Ping , Kimmel Paul L. , Palant Carlos E.
Published: March 2017

Objectives:

Pneumonia is a common cause of hospitalization and can be complicated by the development of acute kidney injury. Acute kidney injury is associated with major adverse kidney events (death, dialysis, and durable loss of renal function [chronic kidney disease]). Because pneumonia and acute kidney injury are in part mediated by inflammation, we hypothesized that when acute kidney injury complicates pneumonia, major adverse kidney events outcomes would be exacerbated. We sought to assess the frequency of major adverse kidney events after a hospitalization for either pneumonia, acute kidney injury, or the combination of both.

Design and Setting:

We conducted a retrospective database analysis of the national Veterans Affairs database for patients with a admission diagnosis of International Classification of Diseases-9 code 584.xx (acute kidney injury) or 486.xx (pneumonia) between October 1, 1999, and December 31, 2005. Three groups of patients were created, based on the diagnosis of the index admission and serum creatinine values: 1) acute kidney injury, 2) pneumonia, and 3) pneumonia with acute kidney injury. Patients with mean baseline estimated glomerular filtration rate less than 45 mL/min/1.73 m2 were excluded.

Measurements and Main Results:

The primary endpoint was major adverse kidney events defined as the composite of death, chronic dialysis, or a permanent loss of renal function after the primary discharge. The observations of 54,894 subjects were analyzed. Mean age was 68.7 ± 12.3 years. The percentage of female was 2.4, 73.3% were Caucasian, and 19.7% were African-American. Differences across the three diagnostic groups were significant for death, 25% decrease in estimated glomerular filtration rate from baseline, major adverse kidney events following admission, and major adverse kidney events during admission (all p < 0.0001). Death alone and major adverse kidney events after discharge were most common in the pneumonia + acute kidney injury group (51% died and 62% reached major adverse kidney events). In both unadjusted and adjusted time to event analyses, patients with pneumonia + acute kidney injury were most likely to die or reach major adverse kidney events.

Conclusions:

When acute kidney injury accompanies pneumonia, postdischarge outcomes are worse than either diagnosis alone. Patients who survive a pneumonia hospitalization and develop acute kidney injury are at high risk for major adverse kidney events including death and should receive careful follow-up.
Predictors of Outcome With Cerebral Autoregulation Monitoring: A Systematic Review and Meta-Analysis
Authors: Rivera-Lara Lucia , Zorrilla-Vaca Andres , Geocadin Romer , Ziai Wendy , Healy Ryan , Thompson Richard , Smielewski Peter , Czosnyka Marek , Hogue Charles W.
Published: March 2017

Objective:

To compare cerebral autoregulation indices as predictors of patient outcome and their dependence on duration of monitoring.

Data Sources:

Systematic literature search and meta-analysis using PubMed, EMBASE, and the Cochrane Library from January 1990 to October 2015.

Study Selection:

We chose articles that assessed the association between cerebral autoregulation indices and dichotomized or continuous outcomes reported as standardized mean differences or correlation coefficients (R), respectively. Animal and validation studies were excluded.

Data Extraction:

Two authors collected and assessed the data independently. The studies were grouped into two sets according to the type of analysis used to assess the relationship between cerebral autoregulation indices and predictors of outcome (standardized mean differences or R).

Data Synthesis:

Thirty-three studies compared cerebral autoregulation indices and patient outcomes using standardized mean differences, and 20 used Rs. The only data available for meta-analysis were from patients with traumatic brain injury or subarachnoid hemorrhage. Based on z score analysis, the best three cerebral autoregulation index predictors of mortality or Glasgow Outcome Scale for patients with traumatic brain injury were the pressure reactivity index, transcranial Doppler-derived mean velocity index based on cerebral perfusion pressure, and autoregulation reactivity index (z scores: 8.97, 6.01, 3.94, respectively). Mean velocity index based on arterial blood pressure did not reach statistical significance for predicting outcome measured as a continuous variable (p = 0.07) for patients with traumatic brain injury. For patients with subarachnoid hemorrhage, autoregulation reactivity index was the only cerebral autoregulation index that predicted patient outcome measured with the Glasgow Outcome Scale as a continuous outcome (R = 0.82; p = 0.001; z score, 3.39). We found a significant correlation between the duration of monitoring and predictive value for mortality (R = 0.78; p < 0.001).

Conclusions:

Three cerebral autoregulation indices, pressure reactivity index, mean velocity index based on cerebral perfusion pressure, and autoregulation reactivity index were the best outcome predictors for patients with traumatic brain injury. For patients with subarachnoid hemorrhage, autoregulation reactivity index was the only cerebral autoregulation index predictor of Glasgow Outcome Scale. Continuous assessment of cerebral autoregulation predicted outcome better than intermittent monitoring.
Escalation of Commitment in the Surgical ICU
Authors: Braxton Carla C. , Robinson Celia N. , Awad Samir S.
Published: March 2017

Objectives:

Escalation of commitment is a business term that describes the continued investment of resources into a project even after there is objective evidence of the project’s impending failure. Escalation of commitment may be a contributor to high healthcare costs associated with critically ill patients as it has been shown that, despite almost certain futility, most ICU costs are incurred in the last week of life. Our objective was to determine if escalation of commitment occurs in healthcare settings, specifically in the surgical ICU. We hypothesize that factors previously identified in business and organizational psychology literature including self-justification, accountability, sunk costs, and cognitive dissonance result in escalation of commitment behavior in the surgical ICU setting resulting in increased utilization of resources and cost.

Design:

A descriptive case study that illustrates common ICU narratives in which escalation of commitment can occur. In addition, we describe factors that are thought to contribute to escalation of commitment behaviors.

Main Results:

Escalation of commitment behavior was observed with self-justification, accountability, and cognitive dissonance accounting for the majority of the behavior. Unlike in business decisions, sunk costs was not as evident. In addition, modulating factors such as personality, individual experience, culture, and gender were identified as contributors to escalation of commitment.

Conclusions:

Escalation of commitment occurs in the surgical ICU, resulting in significant expenditure of resources despite a predicted and often known poor outcome. Recognition of this phenomenon may lead to actions aimed at more rational decision making and may contribute to lowering healthcare costs. Investigation of objective measures that can help aid decision making in the surgical ICU is warranted.
Histomorphology and Immunophenotype of Eczematous Skin Lesions Revisited—Skin Biopsies Are Not Reliable in Differentiating Allergic Contact Dermatitis, Irritant Contact Dermatitis, and Atopic Dermatitis
Authors: Frings Verena G. , Böer-Auer Almut , Breuer Kristine
Published: March 2017

Lesions of allergic contact dermatitis (ACD), irritant contact dermatitis (ICD), and atopic dermatitis (AD) share similar clinical features and thus, their diagnosis can be challenging. The aim of this study was to reassess histopathology and immunophenotyping properties to distinguish between ACD, ICD, and AD. Charts of patients with eczema, who had undergone complete routine diagnostic workup (skin biopsies, patch tests, skin prick tests, and respectively or serum IgE levels), were reviewed. Thirty-five skin biopsy specimens of 28 patients (mean age 64 ± 15 years; ♀ = 13 ♂ = 15) with clear diagnosis of ACD (n = 15), ICD (n = 6), or AD (n = 14) were analyzed. Histomorphological and immunohistochemical (CD3, CD4, CD8, CD11c, CD34, CD123, S100, and IL-17) parameters were evaluated using Kruskal–Wallis test, Wilcoxon test, Fisher exact test, and decision tree analysis. Eosinophils were statistically significant (P = 0.0184), more often observed in AD than in ACD or ICD. No other statistically significant differences were found with regard to epidermal patterns, patterns of dermal infiltrates, or immunophenotyping. Using predictive modeling approaches, dermal eosinophils were found to be associated with AD, necrotic epidermal keratinocytes with ICD, and a focal type of parakeratosis with ACD. As an additional finding, pseudo-Pautrier microabscesses, which were present in the skin of 2 AD and 2 ACD patients, contained myeloid dendritic cells (CD11c+). Differentiation of ACD, ICD, and AD should be based on clinical features and results of allergy tests. Histopathology does not reliably differentiate between ACD, ICD, and AD, but helps to exclude psoriasis, tinea, or T-cell lymphoma.
Perioperative pregabalin administration does not prevent chronic postoperative pain: systematic review with a meta-analysis of randomized trials
Authors: Martinez Valeria , Pichard Xavier , Fletcher Dominique
Published: March 2017

The efficacy of perioperative pregabalin treatment for preventing chronic pain remains a matter of debate. We searched the MEDLINE, EMBASE, LILACS, Cochrane, and Clinical Trial Register databases, and other sources, for randomized controlled trials comparing the effects of pregabalin and placebo. The primary outcome was the incidence of chronic postsurgical pain (CPSP) at 3 months. The secondary endpoints were CPSP at 3, 6, and 12 months and the incidence of chronic postsurgical neuropathic pain at the same time points. A random-effect meta-analysis was performed on the combined data. Evidence quality was rated by the GRADE method. We included 18 studies (2485 patients) in the meta-analysis. Overall, 60% of the trials reporting the primary outcome at 3 months were unpublished; the unpublished trials corresponded to 1492/1884 (79%) of the patients included in these studies. No difference in CPSP incidence between pregabalin and placebo was found at any time point; the risk ratio was 0.87 (0.66, 1.14), I
2 = 57% at 3 months. The evidence was considered to be of moderate quality. Subgroup analysis by publication status, daily dose, type of administration, and type of surgery did not highlight any differences between subgroups. Insufficient data concerning the incidence of chronic postsurgical neuropathic pain were available for any firm recommendation to be made. Pooled data from published and unpublished studies provide no support for the efficacy of pregabalin for preventing CPSP.
Incubation under climate warming affects learning ability and survival in hatchling lizards
Authors: Dayananda Buddhi , Webb Jonathan K.
Published: March 2017

Despite compelling evidence for substantial individual differences in cognitive performance, it is unclear whether cognitive ability influences fitness of wild animals. In many animals, environmental stressors experienced
in utero
can produce substantial variation in the cognitive abilities of offspring. In reptiles, incubation temperatures experienced by embryos can influence hatchling brain function and learning ability. Under climate warming, the eggs of some lizard species may experience higher temperatures, which could affect the cognitive abilities of hatchlings. Whether such changes in cognitive abilities influence the survival of hatchlings is unknown. To determine whether incubation-induced changes in spatial learning ability affect hatchling survival, we incubated velvet gecko,
Amalosia lesueurii
, eggs using two fluctuating temperature regimes to mimic current (cold) versus future (hot) nest temperatures. We measured the spatial learning ability of hatchlings from each treatment, and released individually marked animals at two field sites in southeastern Australia. Hatchlings from hot-incubated eggs were slower learners than hatchlings from cold-incubated eggs. Survival analyses revealed that hatchlings with higher learning scores had higher survival than hatchlings with poor learning scores. Our results show that incubation temperature affects spatial learning ability in hatchling lizards, and that such changes can influence the survival of hatchlings in the wild.
The impact of temperature changes on vector-borne disease transmission:
Culicoides
midges and bluetongue virus
Authors: Brand Samuel P. C. , Keeling Matt J.
Published: March 2017

It is a long recognized fact that climatic variations, especially temperature, affect the life history of biting insects. This is particularly important when considering vector-borne diseases, especially in temperate regions where climatic fluctuations are large. In general, it has been found that most biological processes occur at a faster rate at higher temperatures, although not all processes change in the same manner. This differential response to temperature, often considered as a trade-off between onward transmission and vector life expectancy, leads to the total transmission potential of an infected vector being maximized at intermediate temperatures. Here we go beyond the concept of a static optimal temperature, and mathematically model how realistic temperature variation impacts transmission dynamics. We use bluetongue virus (BTV), under UK temperatures and transmitted by
Culicoides
midges, as a well-studied example where temperature fluctuations play a major role. We first consider an optimal temperature profile that maximizes transmission, and show that this is characterized by a warm day to maximize biting followed by cooler weather to maximize vector life expectancy. This understanding can then be related to recorded representative temperature patterns for England, the UK region which has experienced BTV cases, allowing us to infer historical transmissibility of BTV, as well as using forecasts of climate change to predict future transmissibility. Our results show that when BTV first invaded northern Europe in 2006 the cumulative transmission intensity was higher than any point in the last 50 years, although with climate change such high risks are the expected norm by 2050. Such predictions would indicate that regular BTV epizootics should be expected in the UK in the future.
High-skilled labour mobility in Europe before and after the 2004 enlargement
Authors: Petersen Alexander M. , Puliga Michelangelo
Published: March 2017

The extent to which international high-skilled mobility channels are forming is a question of great importance in an increasingly global knowledge-based economy. One factor facilitating the growth of high-skilled labour markets is the standardization of certifiable degrees meriting international recognition. Within this context, we analysed an extensive high-skilled mobility database comprising roughly 382 000 individuals from five broad profession groups (Medical, Education, Technical, Science & Engineering and Business & Legal) over the period 1997–2014, using the 13-country expansion of the European Union (EU) to provide insight into labour market integration. We compare the periods before and after the 2004 enlargement, showing the emergence of a new east–west migration channel between the 13 mostly eastern EU entrants (E) and the rest of the western European countries (W). Indeed, we observe a net directional loss of human capital from E → W, representing 29% of the total mobility after 2004. Nevertheless, the counter-migration from W → E is 7% of the total mobility over the same period, signalling the emergence of brain circulation within the EU. Our analysis of the country–country mobility networks and the country–profession bipartite networks provides timely quantitative evidence for the convergent integration of the EU, and highlights the central role of the UK and Germany as high-skilled labour hubs. We conclude with two data-driven models to explore the structural dynamics of the mobility networks. First, we develop a reconfiguration model to explore the potential ramifications of Brexit and the degree to which redirection of high-skilled labourers away from the UK may impact the integration of the rest of the European mobility network. Second, we use a panel regression model to explain empirical high-skilled mobility rates in terms of various economic ‘push–pull’ factors, the results of which show that government expenditure on education,per capitawealth, geographical proximity and labour force size are significant attractive features of destination countries.
Frequency tuning and directional sensitivity of tympanal vibrations in the field cricketGryllus bimaculatus
Authors: Lankheet Martin J. , Cerkvenik Uroš , Larsen Ole N. , van Leeuwen Johan L.
Published: March 2017

Female field crickets use phonotaxis to locate males by their calling song. Male song production and female behavioural sensitivity form a pair of matched frequency filters, which inGryllus bimaculatusare tuned to a frequency of about 4.7 kHz. Directional sensitivity is supported by an elaborate system of acoustic tracheae, which make the ears function as pressure difference receivers. As a result, phase differences between left and right sound inputs are transformed into vibration amplitude differences. Here we critically tested the hypothesis that acoustic properties of internal transmissions play a major role in tuning directional sensitivity to the calling song frequency, by measuring tympanal vibrations as a function of sound direction and frequency. Rather than sharp frequency tuning of directional sensitivity corresponding to the calling song, we found broad frequency tuning, with optima shifted to higher frequencies. These findings agree with predictions from a vector summation model for combining external and internal sounds. We show that the model provides robust directional sensitivity that is, however, broadly tuned with an optimum well above the calling song frequency. We therefore advocate that additional filtering, e.g. at a higher (neuronal) level, significantly contributes to frequency tuning of directional sensitivity.
Atypical centrioles are present in
Tribolium
sperm
Authors: Fishman E. L. , Jo Kyoung , Ha Andrew , Royfman Rachel , Zinn Ashtyn , Krishnamurthy Malathi , Avidor-Reiss Tomer
Published: March 2017

Typical centrioles are made of microtubules organized in ninefold symmetry. Most animal somatic cells have two centrioles for normal cell division and function. These centrioles originate from the zygote, but because the oocyte does not provide any centrioles, it is surprising that the zygotes of many animals are thought to inherit only one centriole from the sperm. Recently, in the sperm of
Drosophila melanogaster
, we discovered a second centriolar structure, the proximal centriole-like structure (PCL), which functions in the zygote. Whether the sperm of other insects has a second centriolar structure is unknown. Here, we characterized spermiogenesis in the red flour beetle,
Tribolium castaneum
. Electron microscopy suggests that
Tribolium
has one microtubule-based centriole at the tip of the axoneme and a structure similar to the PCL, which lacks microtubules and lies in a cytoplasmic invagination of the nucleus. Immunostaining against the orthologue of the centriole/PCL protein, Ana1, also recognizes two centrioles near the nucleus during spermiogenesis: one that is microtubule-based at the tip of the axoneme, suggesting it is the centriole; and another that is more proximal and appears during early spermiogenesis, suggesting it is the PCL. Together, these findings suggest that
Tribolium
sperm has one microtubule-based centriole and one microtubule-lacking centriole.
Quantifying the energy stores of capital breeding humpback whales and income breeding sperm whales using historical whaling records
Authors: Irvine Lyn G. , Thums Michele , Hanson Christine E. , McMahon Clive R. , Hindell Mark A.
Published: March 2017

Cetacean energy stores are known to vary according to life history, reproductive status and time of year; however, the opportunity to quantify these relationships is rare. Using a unique set of historical whaling records from Western Australia (1952–1963), we investigated energy stores of large cetaceans with differing life histories, and quantified the relationship between total body lipid and length for humpback whales (Megaptera novaeangliae)(n = 905) and sperm whales(Physeter macrocephalus)(n = 1961). We found that total body lipid increased with body length in both humpback and sperm whales, consistent with size-related energy stores. Male humpback whales stored 2.49 kl (15.6 barrels) (31.9–74.9%) more lipid than male sperm whales of equivalent length, to fuel their annual migration. Relative lipid stores of sperm whales (males) were constant throughout the year, while those of humpback whales varied with reproductive class and sampling date. Pregnant female humpback whales had higher relative energy stores than non-pregnant females and males (26.2% and 37.4%, respectively), to fuel the energy demands of gestation and lactation. Those that reached the sampling site later (en routeto their breeding grounds) carried higher lipid stores than those that arrived earlier, possibly reflecting individual variation in residency times in the Antarctic feeding grounds. Importantly, longer pregnant females had relatively larger energy stores than the shorter pregnant females, indicating that the smaller individuals may experience higher levels of energetic stress during the migration fast. The relationships we developed between body lipid and length can be used to inform bioenergetics and ecosystem models when such detailed information is not available.
Human mobility networks and persistence of rapidly mutating pathogens
Authors: Aleta Alberto , Hisi Andreia N. S. , Meloni Sandro , Poletto Chiara , Colizza Vittoria , Moreno Yamir
Published: March 2017

Rapidly mutating pathogens may be able to persist in the population and reach an endemic equilibrium by escaping hosts’ acquired immunity. For such diseases, multiple biological, environmental and population-level mechanisms determine the dynamics of the outbreak, including pathogen's epidemiological traits (e.g. transmissibility, infectious period and duration of immunity), seasonality, interaction with other circulating strains and hosts’ mixing and spatial fragmentation. Here, we study a susceptible-infected-recovered-susceptible model on a metapopulation where individuals are distributed in sub-populations connected via a network of mobility flows. Through extensive numerical simulations, we explore the phase space of pathogen's persistence and map the dynamical regimes of the pathogen following emergence. Our results show that spatial fragmentation and mobility play a key role in the persistence of the disease whose maximum is reached at intermediate mobility values. We describe the occurrence of different phenomena including local extinction and emergence of epidemic waves, and assess the conditions for large-scale spreading. Findings are highlighted in reference to previous studies and to real scenarios. Our work uncovers the crucial role of hosts’ mobility on the ecological dynamics of rapidly mutating pathogens, opening the path for further studies on disease ecology in the presence of a complex and heterogeneous environment.
Mechanisms of vortices termination in the cardiac muscle
Authors: Hornung D. , Biktashev V. N. , Otani N. F. , Shajahan T. K. , Baig T. , Berg S. , Han S. , Krinsky V. I. , Luther S.
Published: March 2017

We propose a solution to a long-standing problem: how to terminate multiple vortices in the heart, when the locations of their cores and their critical time windows are unknown. We scan the phases of all pinned vortices in parallel with electric field pulses (E-pulses). We specify a condition on pacing parameters that guarantees termination of one vortex. For more than one vortex with significantly different frequencies, the success of scanning depends on chance, and all vortices are terminated with a success rate of less than one. We found that a similar mechanism terminates also a free (not pinned) vortex. A series of about 500 experiments with termination of ventricular fibrillation by E-pulses in pig isolated hearts is evidence that pinned vortices, hidden from direct observation, are significant in fibrillation. These results form a physical basis needed for the creation of new effective low energy defibrillation methods based on the termination of vortices underlying fibrillation.
Niche partitioning and the role of intraspecific niche variation in structuring a guild of generalist anurans
Authors: Cloyed Carl S. , Eason Perri K.
Published: March 2017

Intra-population niche differences in generalist foragers have captured the interest of ecologists, because such individuality can have important ecological and evolutionary implications. Few researchers have investigated how these differences affect the relationships among ecologically similar, sympatric species. Using stable isotopes, stomach contents, morphology and habitat preference, we examined niche partitioning within a group of five anurans and determined whether variation within species could facilitate resource partitioning. Species partitioned their niches by trophic level and by foraging habitat. However, there was considerable intraspecific variation in trophic level, with larger individuals generally feeding at higher trophic levels. For species at intermediate trophic levels, smaller individuals overlapped in trophic level with individuals of smaller species and larger individuals overlapped with the smallest individuals from larger species. Species varied in carbon isotopes; species with enriched carbon isotope ratios foraged farther from ponds, whereas species with depleted carbon isotope values foraged closer to ponds. Our study shows that these species partition their niches by feeding at different trophic levels and foraging at different distances from ponds. The intraspecific variation in trophic level decreased the number of individuals from each species that overlapped in trophic level with individuals from other species, which can facilitate species coexistence.
Fluid dynamics of acoustic and hydrodynamic cavitation in hydraulic power systems
Authors: Ferrari A.
Published: March 2017

Cavitation is the transition from a liquid to a vapour phase, due to a drop in pressure to the level of the vapour tension of the fluid. Two kinds of cavitation have been reviewed here: acoustic cavitation and hydrodynamic cavitation. As acoustic cavitation in engineering systems is related to the propagation of waves through a region subjected to liquid vaporization, the available expressions of the sound speed are discussed. One of the main effects of hydrodynamic cavitation in the nozzles and orifices of hydraulic power systems is a reduction in flow permeability. Different discharge coefficient formulae are analysed in this paper: the Reynolds number and the cavitation number result to be the key fluid dynamical parameters for liquid and cavitating flows, respectively. The latest advances in the characterization of different cavitation regimes in a nozzle, as the cavitation number reduces, are presented. The physical cause of choked flows is explained, and an analogy between cavitation and supersonic aerodynamic flows is proposed. The main approaches to cavitation modelling in hydraulic power systems are also reviewed: these are divided into homogeneous-mixture and two-phase models. The homogeneous-mixture models are further subdivided into barotropic and baroclinic models. The advantages and disadvantages of an implementation of the complete Rayleigh–Plesset equation are examined.
Equilibrium shapes of a heterogeneous bubble in an electric field: a variational formulation and numerical verifications
Authors: Wang Hanxiong , Liu Liping , Liu Dong
Published: March 2017

The equilibrium shape of a bubble/droplet in an electric field is important for electrowetting over dielectrics (EWOD), electrohydrodynamic (EHD) enhancement for heat transfer and electro-deformation of a single biological cell among others. In this work, we develop a general variational formulation in account of electro-mechanical couplings. In the context of EHD, we identify the free energy functional and the associated energy minimization problem that determines the equilibrium shape of a bubble in an electric field. Based on this variational formulation, we implement a fixed mesh level-set gradient method for computing the equilibrium shapes. This numerical scheme is efficient and validated by comparing with analytical solutions at the absence of electric field and experimental results at the presence of electric field. We also present simulation results for zero gravity which will be useful for space applications. The variational formulation and numerical scheme are anticipated to have broad applications in areas of EWOD, EHD and electro-deformation in biomechanics.
History dependence and the continuum approximation breakdown: the impact of domain growth on Turing’s instability
Authors: Klika Václav , Gaffney Eamonn A.
Published: March 2017

A diffusively driven instability has been hypothesized as a mechanism to drive spatial self-organization in biological systems since the seminal work of Turing. Such systems are often considered on a growing domain, but traditional theoretical studies have only treated the domain size as a bifurcation parameter, neglecting the system non-autonomy. More recently, the conditions for a diffusively driven instability on a growing domain have been determined under stringent conditions, including slow growth, a restriction on the temporal interval over which the prospect of an instability can be considered and a neglect of the impact that time evolution has on the stability properties of the homogeneous reference state from which heterogeneity emerges. Here, we firstly relax this latter assumption and observe that the conditions for the Turing instability are much more complex and depend on the history of the system in general. We proceed to relax all the above constraints, making analytical progress by focusing on specific examples. With faster growth, instabilities can grow transiently and decay, making the prediction of a prospective Turing instability much more difficult. In addition, arbitrarily high spatial frequencies can destabilize, in which case the continuum approximation is predicted to break down.
Microprocessors: the engines of the digital age
Authors: Furber Steve
Published: March 2017

The microprocessor—a computer central processing unit integrated onto a single microchip—has come to dominate computing across all of its scales from the tiniest consumer appliance to the largest supercomputer. This dominance has taken decades to achieve, but an irresistible logic made the ultimate outcome inevitable. The objectives of this Perspective paper are to offer a brief history of the development of the microprocessor and to answer questions such as: where did the microprocessor come from, where is it now, and where might it go in the future?
Life-history evolution in ants: the case ofCardiocondyla
Authors: Heinze Jürgen
Published: March 2017

Ants are important components of most terrestrial habitats, and a better knowledge of the diversity of their life histories is essential to understand many aspects of ecosystem functioning. The myrmicine genusCardiocondylashows a wide range of colony structures, reproductive behaviours, queen and male lifespans, and habitat use. Reconstructing the evolutionary pathways of individual and social phenotypic traits suggests that the ancestral life history ofCardiocondylawas characterized by the presence of multiple, short-lived queens in small-sized colonies and a male polyphenism with winged dispersers and wingless fighters, which engage in lethal combat over female sexuals within their natal nests. Single queening, queen polyphenism, the loss of winged males and tolerance among wingless males appear to be derived traits that evolved with changes in nesting habits, colony size and the spread from tropical to seasonal environments. The aim of this review is to bring together the information on life-history evolution inCardiocondylaand to highlight the suitability of this genus for functional genomic studies of adaptation, phenotypic plasticity, senescence, invasiveness and other key life-history traits of ants.
Control of Hox transcription factor concentration and cell-to-cell variability by an auto-regulatory switch
Authors: Papadopoulos Dimitrios K. , Skouloudaki Kassiani , Engstrom Ylva , Terenius Lars , Rigler Rudolf , Zechner Christoph , Vukojevic Vladana , Tomancak Pavel
Published: March 2017

The variability in transcription factor concentration among cells is an important developmental determinant, yet how variability is controlled remains poorly understood. Studies of variability have focused predominantly on monitoring mRNA production noise. Little information exists about transcription factor protein variability, since this requires the use of quantitative methods with single-molecule sensitivity. Using Fluorescence Correlation Spectroscopy (FCS), we characterised the concentration and variability of 14 endogenously tagged TFs in live Drosophila imaginal discs. For the Hox TF Antennapedia we investigated whether protein variability results from random stochastic events or is developmentally regulated. We found that Antennapedia transitioned from low concentration/high variability early, to high concentration/low variability later, in development. FCS and temporally resolved genetic studies uncovered that Antp itself is necessary and sufficient to drive a developmental regulatory switch from auto-activation to auto-repression, thereby reducing variability. This switch is controlled by progressive changes in relative concentrations of preferentially activating and repressing Antennapedia isoforms, which bind chromatin with different affinities. Mathematical modelling demonstrated that the experimentally supported auto-regulatory circuit can explain the increase of Antennapedia concentration and suppression of variability over time.
Habitat fragmentation causes coevolutionary burning spots
Authors: De Kort H. , Baguette M. , Prunier J.G , Tessier M. , Monsimet J. , Turlure C. , Stevens V.M.
Published: March 2017

Habitat fragmentation increasingly threatens the services provided by natural communities and ecosystem worldwide. An understanding of the underlying eco-evolutionary processes in natural settings is lacking, yet critical to realistic and sustainable conservation. Through integrating the multivariate genetic, biotic and abiotic facets of a natural community network experiencing various degrees of habitat fragmentation, we provide unique insights into the processes underlying community functioning in real, natural conditions. The focal community network comprises a parasitic butterfly of conservation concern, and its two obligatory host species, a plant and an ant. We show that fragmentation of butterfly habitat has the potential to impair the balance between dispersal and coevolution. This process can cause coevolutionary burning spots of decreased genetic diversity and therefore of increased extinction risk. We stress that ignoring such eco-evolutionary feed-backs inherent to the very functioning of natural communities can strongly impact their persistence.

One Sentence Summary:

Communities under threat of habitat fragmentation suffer increased extinction risk through coevolutionary overheating.
Tracking electron uptake from a cathode intoShewanellacells: implications for generating maintenance energy from solid substrates
Authors: Rowe Annette R. , Rajeev Pournami , Jain Abhiney , Pirbadian Sahand , Okamotao Akihiro , Gralnick Jeffrey A. , El-Naggar Mohamed Y. , Nealson Kenneth H.
Published: March 2017

While typically investigated as a microorganism capable of extracellular electron transfer to minerals or anodes,Shewanella oneidensisMR-1 can also facilitate electron flow from a cathode to terminal electron acceptors such as fumarate or oxygen, thereby providing a model systems for a process that has significant environmental and technological implications. This work demonstrates that cathodic electrons enter the electron transport chain of S.oneidensiswhen oxygen is used as the terminal electron acceptor. The effect of electron transport chain inhibitors suggested that a proton gradient is generated during cathode-oxidation, consistent with the higher cellular ATP levels measured in cathode-respiring cells relative to controls. Cathode oxidation also correlated with an increase in the cellular redox (NADH/FMNH2) pool using a bioluminescent assay. Using a proton uncoupler, generation of NADH/FMNH2under cathodic conditions was linked to reverse electron flow mediated by the proton pumping NADH oxidase Complex I. A decrease in cathodic electron uptake was observed in various mutant strains including those lacking the extracellular electron transfer components necessary for anodic current generation. While no cell growth was observed under these conditions, here we show that cathode oxidation is linked to cellular energy conservation, resulting in a quantifiable reduction in cellular decay rate. This work highlights a potential mechanism for cell survival and/or persistence in environments where growth and division are severely limited.