bluuebunny/crossref_metadata_2025_split huggingface dataset:
The challenge of promoting algorithmic thinking of both sciences‐ and humanities‐oriented learners
Authors: Katai Z. 
Published: May 2014

AbstractThe research results we present in this paper reveal that properly calibrated e‐learning tools have potential to effectively promote the algorithmic thinking of both science‐oriented and humanities‐oriented students. After students had watched an illustration (by a folk dance choreography) and an animation of the studied sorting algorithm (bubble sort), they were invited to predict and perform [(1) to reconstruct on the same input; (2) to orchestrate on a random sequence stored in a white array; (3) to orchestrate on a black‐box sequence] the entire step sequence of the algorithm (using the interactive visual learning environment we developed). The results of the experiment show that while science‐oriented students' performance proved superior to those of their humanities‐oriented colleagues, the differences were observed to diminish as both groups advanced with their e‐learning tasks. Although drawing general conclusions would be premature, we can conclude that there are no unbridgeable differences in the way these two groups relate to e‐learning processes that aim to promote algorithmic thinking. Our findings also emphasize the key importance of some motivational principles in facilitating algorithmic thinking: the principle of moderate and progressive challenge, the principle of gradual shift from concrete to abstract and the principle of genuine active involvement.
Interactive effects of competition and social environment on the expression of sexual dimorphism
Authors: De Lisle S. P. , Rowe L. 
Published: May 2014

AbstractThe expression of sexual dimorphism is expected to be influenced by the acquisition of resources available to allocate to trait growth, combined with sex‐specific patterns of resource allocation. Resource acquisition in the wild may be mediated by a variety of ecological factors, such as the density of interspecific competitors. Allocation may in turn depend on social contexts, such as sex ratio, that alter the pay‐off for investment in sexual traits. How these factors interact to promote or constrain the expression and evolution of sexual dimorphism is poorly understood. We manipulated sex ratio and interspecific resource competition over the growing season of red‐spotted newts (Notophthalmus viridescens) in artificial ponds. Fish competitors had a stronger effect on female than male growth, which effectively eliminated the expression of sexual size dimorphism. In addition, newt sex ratio influenced fish growth, leading to reduction in fish mass with an increase in female newt frequency. Fish also reduced the expression of male tail height, a sexually selected trait, but only in tanks with a female‐biased sex ratio. This suggests males alter their resource allocation pattern in response to the strength of sexual selection. Our results demonstrate that ecologically and socially mediated interactions between sex‐specific resource acquisition and allocation can contribute to variation in the expression of sexual dimorphism.
Inbreeding depression in male gametic performance
Authors: Losdat S. , Chang S.‐M. , Reid J. M. 
Published: May 2014

AbstractOne key objective in evolutionary ecology is to understand the magnitude of inbreeding depression expressed across sex‐specific components of fitness. One major component of male fitness is fertilization success, which depends on male gametic performance (sperm and pollen performance in animals and plants, respectively). Inbreeding depression in male gametic performance could create sex‐specific inbreeding depression in fitness, increase the benefit of inbreeding avoidance and reduce the efficacy of artificial insemination and pollination. However, there has been no assessment of the degree to which inbreeding generally depresses male gametic performance and hence post‐copulatory or post‐pollination fertilization success. Because inbreeding depression is understood to be a property of diploid entities, it is not clear what degree of inbreeding depression in haploid gametic performance should be expected. Here, we first summarize how inbreeding depression in male gametic performance could potentially arise through gene expression in associated diploid cells and/or reduced genetic diversity among haploid gametes. We then review published studies that estimate the magnitude of inbreeding depression in traits measuring components of sperm or pollen quantity, quality and competitiveness. Across 51 published studies covering 183 study traits, the grand mean inbreeding load was approximately one haploid lethal equivalent, suggesting that inbreeding depresses male gametic performance across diverse systems and traits. However, there was an almost complete lack of explicit estimates from wild populations. Future studies should quantify inbreeding depression in systematic sets of gametic traits under naturally competitive and noncompetitive conditions and quantify the degree to which gamete phenotypes and performance reflect haploid vs. diploid gene expression.
Sex drives intracellular conflict in yeast
Authors: Harrison E. , MacLean R. C. , Koufopanou V. , Burt A. 
Published: May 2014

AbstractTheory predicts that sex can drive the evolution of conflict within the cell. During asexual reproduction, genetic material within the cell is inherited as a single unit, selecting for cooperation both within the genome as well as between the extra‐genomic elements within the cell (e.g. plasmids and endosymbionts). Under sexual reproduction, this unity is broken down as parental genomes are distributed between meiotic progeny. Genetic elements able to transmit to more than 50% of meiotic progeny have a transmission advantage over the rest of the genome and are able to spread, even where they reduce the fitness of the individual as a whole. Sexual reproduction is therefore expected to drive the evolution of selfish genetic elements (SGEs). Here, we directly test this hypothesis by studying the evolution of two independent SGEs, the 2‐μm plasmid and selfish mitochondria, in populations of Saccharomyces cerevisiae. Following 22 rounds of sexual reproduction, 2‐μm copy number increased by approximately 13.2 (± 5.6) copies per cell, whereas in asexual populations copy number decreased by approximately 5.1 (± 1.5) copies per cell. Given that the burden imposed by this parasite increases with copy number, these results support the idea that sex drives the evolution of increased SGE virulence. Moreover, we found that mitochondria that are respiratory‐deficient rapidly invaded sexual but not asexual populations, demonstrating that frequent outcrossed sex can drive the de novo evolution of genetic parasites. Our study highlights the genomic perils of sex and suggests that SGEs may play a key role in driving major evolutionary transitions, such as uniparental inheritance.
Maternal effects are long‐lasting and influence female offspring's reproductive strategy in the swordtail fish Xiphophorus multilineatus
Authors: Murphy A. D. , Goedert D. , Morris M. R. 
Published: May 2014

AbstractThe adaptive benefits of maternal investment into individual offspring (inherited environmental effects) will be shaped by selection on mothers as well as their offspring, often across variable environments. We examined how a mother's nutritional environment interacted with her offspring's nutritional and social environment in Xiphophorus multilineatus, a live‐bearing fish. Fry from mothers reared on two different nutritional diets (HQ = high quality and LQ = low quality) were all reared on a LQ diet in addition to being split between two social treatments: exposed to a large adult male during development and not exposed. Mothers raised on a HQ diet produce offspring that were not only initially larger (at 14 days of age), but grew faster, and were larger at sexual maturity. Male offspring from mothers raised on both diets responded to the exposure to courter males by growing faster; however, the response of their sisters varied with mother's diet; females from HQ diet mothers reduced growth if exposed to a courter male, whereas females from LQ diet mothers increased growth. Therefore, we detected variation in maternal investment depending on female size and diet, and the effects of this variation on offspring were long‐lasting and sex specific. Our results support the maternal stress hypothesis, with selection on mothers to reduce investment in low‐quality environments. In addition, the interaction we detected between the mother's nutritional environment and the female offspring's social environment suggests that female offspring adopted different reproductive strategies depending on maternal investment.
Immersion challenge with low and highly virulent infectious salmon anaemia virus reveals different pathogenesis in Atlantic salmon, Salmo salar L.
Authors: McBeath A , Aamelfot M , Christiansen D H , Matejusova I , Markussen T , Kaldhusdal M , Dale O B , Weli S C , Falk K 
Published: May 2014

AbstractThe salmonid orthomyxovirus infectious salmon anaemia virus (ISAV) causes disease of varying severity in farmed Atlantic salmon, Salmo salar L. Field observations suggest that host factors, the environment and differences between ISAV strains attribute to the large variation in disease progression. Variation in host mortality and dissemination of ISAV isolates with high and low virulence (based on a previously published injection challenge) were investigated using immersion challenge. Virus dissemination was determined using real‐time PCR and immunohistochemistry in several organs, including blood. Surprisingly, the low virulent virus (LVI) replicated and produced nucleoprotein at earlier time points post‐infection compared to the virus of high virulence (HVI). This was particularly noticeable in the gills as indicated by different viral load profiles. However, the HVI reached a higher maximum viral load in all tested organs and full blood. This was associated with a higher mortality of 100% as compared to 20% in the LVI group by day 23 post‐infection. Immersion challenge represented a more natural infection method and suggested that specific entry routes into the fish may be of key importance between ISAV strains. The results suggest that a difference in virulence is important for variations in virus dissemination and pathogenesis (disease development).
Single and Sequential Application of Electrolyzed Water with Benzalkonium Chloride or Peracetic Acid for Removal of Staphylococcus Aureus Biofilms
Authors: Vázquez‐Sánchez D. , Cabo M.L. , Rodríguez‐Herrera J.J. 
Published: May 2014

AbstractThe effectiveness of electrolyzed water (EW) to remove biofilms formed on stainless steel by Staphylococcus aureus strains isolated from fishery products was assessed. The bactericidal activity of EW against biofilms was hardly any affected by any variations in the pH of production. Neutral EW (NEW) was therefore used in subsequent studies as it has a higher potential for long‐term application than acidic EW (due to a lower corrosiveness and toxicity) and due to the higher yield rate of the production unit at neutral pH.The application of NEW caused a high reduction in the number of viable biofilm cells initially. However, a high available chlorine concentration (800 mg/L) was needed to achieve logarithmic reductions (LR) demanded by the European quantitative surface test of bactericidal activity (≥ 4 log CFU/cm2 after 5 min). A double sequential application of NEW at much lower concentrations for 5 min each allowed LR ≥ 4 log CFU/cm2 to be reached in most of the experimental range. Sequential applications of NEW and either benzalkonium chloride or peracetic acid (PAA) showed a similar effect, with PAA‐NEW being most effective. The combination of NEW with other antimicrobial treatments can thus be an environmentally friendly alternative to disinfection protocols traditionally used in the food industry.Practical ApplicationsSpain is the largest producer and the second largest consumer of seafood in the European Union, thus ensuring the safety of these products is of outmost importance. However, a high incidence of Staphylococcus aureus was recently found in fishery products marketed in Spain, which questioned the efficacy of disinfectants traditionally applied in the food industry. This study focused on electrolyzed water (EW) because it is an environmentally friendly, safe‐to‐use and relatively inexpensive option. The data obtained in this study demonstrated that the combination of neutral EW and other disinfectants resulted in an effective alternative to control the contamination of food‐processing facilities by foodborne pathogens such as S. aureus.
Testosterone or Oestradiol Implants in the Medial Preoptic Area Induce Mating in Noncopulating Male Rats
Authors: Antonio‐Cabrera E. , Paredes R. G. 
Published: May 2014

Noncopulating (NC) male rats are those males that do not mount, intromit or ejaculate when repeatedly tested with receptive females. The lack of sexual behaviour in these males is not associated with alterations in testosterone or oestradiol (E2) plasma concentrations. Instead, it has been shown that androgen receptors are higher and oestrogen receptors are lower in the medial preoptic area (MPOA) of NC male rats than those observed in copulating (C) male rats. We have also observed reduced aromatase activity in the MPOA (but not in other brain regions) of NC male rats. The aim of the present study was to determine whether testosterone or E2 implants in the MPOA of NC male rats could induce sexual behaviour. Accordingly, in Experiment 1, we evaluated the long‐term effects of testosterone or E2 implants in the MPOA, the ventromedial nucleus of the hypothalamus or the medial amygdala with respect to inducing sexual behaviour in castrated C male rats. Male rats were bilaterally implanted with a guide cannula, either empty or containing testosterone or E2. Starting 1 week later, all male rats were mated once weekly for 5 months. As described previously, the site where hormone implants most consistently induced sexual behaviour in castrated C male rats was the MPOA. Experiment 1 extended these findings showing that the males continued mating even 5 months after the implant. In the second experiment, NC males were implanted in the MPOA with a guide cannula empty or filled with testosterone or E2. One week after the testosterone or E2 implant, the percentage of males that mounted and intromitted started to increase and, 5 weeks after the implant, 50% of the subjects displayed mounts and intromissions. All NC males implanted with testosterone ejaculated consistently from week 11 after the implant until the end of testing (5 months), whereas all subjects implanted with E2 ejaculated from week 16 after the implant until the end of testing. These results support the hypothesis that, in the MPOA of NC male rats, there is a hormonal alteration associated with the lack of sexual behaviour.
Diurnal and Circadian Oscillations in Expression of Kisspeptin, Kisspeptin Receptor and Gonadotrophin‐Releasing Hormone 2 Genes in the Grass Puffer, A Semilunar‐Synchronised Spawner
Authors: Ando H. , Ogawa S. , Shahjahan Md. , Ikegami T. , Doi H. , Hattori A. , Parhar I. 
Published: May 2014

In seasonally breeding animals, the circadian and photoperiodic regulation of neuroendocrine system is important for precisely‐timed reproduction. Kisspeptin, encoded by the Kiss1 gene, acts as a principal positive regulator of the reproductive axis by stimulating gonadotrophin‐releasing hormone (GnRH) neurone activity in vertebrates. However, the precise mechanisms underlying the cyclic regulation of the kisspeptin neuroendocrine system remain largely unknown. The grass puffer, Takifugu niphobles, exhibits a unique spawning rhythm: spawning occurs 1.5–2 h before high tide on the day of spring tide every 2 weeks, and the spawning rhythm is connected to circadian and lunar‐/tide‐related clock mechanisms. The grass puffer has only one kisspeptin gene (kiss2), which is expressed in a single neural population in the preoptic area (POA), and has one kisspeptin receptor gene (kiss2r), which is expressed in the POA and the nucleus dorsomedialis thalami. Both kiss2 and kiss2r show diurnal variations in expression levels, with a peak at Zeitgeber time (ZT) 6 (middle of day time) under the light/dark conditions. They also show circadian expression with a peak at circadian time 15 (beginning of subjective night‐time) under constant darkness. The synchronous and diurnal oscillations of kiss2 and kiss2r expression suggest that the action of Kiss2 in the diencephalon is highly dependent on time. Moreover, midbrain GnRH2 gene (gnrh2) but not GnRH1 or GnRH3 genes show a unique semidiurnal oscillation with two peaks at ZT6 and ZT18 within a day. The cyclic expression of kiss2, kiss2r and gnrh2 may be important in the control of the precisely‐timed diurnal and semilunar spawning rhythm of the grass puffer, possibly through the circadian clock and melatonin, which may transmit the photoperiodic information of daylight and moonlight to the reproductive neuroendocrine centre in the hypothalamus.
Evidence that Insulin Signalling in Gonadotrophin‐Releasing Hormone and Kisspeptin Neurones does not Play an Essential Role in Metabolic Regulation of Fertility in Mice
Authors: Evans M. C. , Rizwan M. , Mayer C. , Boehm U. , Anderson G. M. 
Published: May 2014

Insulin in the brain plays an important role in regulating reproductive function, as demonstrated via conditional brain‐specific insulin receptor (Insr) deletion (knockout). However, the specific neuronal target cells mediating the central effects of insulin on the reproductive axis remain unidentified. We first investigated whether insulin can act via direct effects on gonadotrophin‐releasing hormone (GnRH) neurones. After clearly detecting Insr mRNA in an immunopurified GnRH cell fraction, we confirmed the presence of insulin receptor protein (InsR) in approximately 82% of GnRH neurones using dual‐label immunohistochemistry. However, we did not observe any insulin‐induced phospho‐Akt (pAkt) or phospho‐extracellular‐signal‐regulated kinase 1/2 in GnRH neurones, and therefore we investigated whether insulin signals via kisspeptin neurones to modulate GnRH release. Using dual‐label immunohistochemistry, InsRs were detected only in approximately 5% of kisspeptin‐immunoreactive cells. Insulin‐induced pAkt was not observed in any kisspeptin‐immunoreactive cells in either the rostral periventricular region of the third ventricle or arcuate nucleus in response to 200 mU of insulin treatment, although a more pharmacological dose (10 U) induced pronounced (> 20%) pAkt–kisspeptin coexpression in both regions. To confirm that insulin signalling via kisspeptin neurones does not critically modulate reproductive function, we generated kisspeptin‐specific InsR knockout (KIRKO) mice and assessed multiple reproductive and metabolic parameters. No significant differences in puberty onset, oestrous cyclicity or reproductive competency were observed in the female or male KIRKO mice compared to their control littermates. However, significantly decreased fasting insulin (P < 0.05) and a nonsignificant trend towards reduced body weight were observed in male KIRKO mice. Thus, InsR signalling in kisspeptin cells is not critical for puberty onset or reproductive competency, although it may have a small metabolic effect in males.
AMP‐activated protein kinase: a key regulator of energy balance with many roles in human disease
Authors: Grahame Hardie D. 
Published: May 2014

AbstractThe AMP‐activated protein kinase (AMPK) is a sensor of cellular energy status that regulates cellular and whole‐body energy balance. A recently reported crystal structure has illuminated the complex regulatory mechanisms by which AMP and ADP cause activation of AMPK, involving phosphorylation by the upstream kinase LKB1. Once activated by falling cellular energy status, AMPK activates catabolic pathways that generate ATP whilst inhibiting anabolic pathways and other cellular processes that consume ATP. A role of AMPK is implicated in many human diseases. Mutations in the γ2 subunit cause heart disease due to excessive glycogen storage in cardiac myocytes, leading to ventricular pre‐excitation. AMPK‐activating drugs reverse many of the metabolic defects associated with insulin resistance, and recent findings suggest that the insulin‐sensitizing effects of the widely used antidiabetic drug metformin are mediated by AMPK. The upstream kinase LKB1 is a tumour suppressor, and AMPK may exert many of its antitumour effects. AMPK activation promotes the oxidative metabolism typical of quiescent cells, rather than the aerobic glycolysis observed in tumour cells and cells involved in inflammation, explaining in part why AMPK activators have both antitumour and anti‐inflammatory effects. Salicylate (the major in vivo metabolite of aspirin) activates AMPK, and this could be responsible for at least some of the anticancer and anti‐inflammatory effects of aspirin. In addition to metformin and salicylates, novel drugs that modulate AMPK are likely to enter clinical trials soon. Finally, AMPK may be involved in viral infection: downregulation of AMPK during hepatitis C virus infection appears to be essential for efficient viral replication.
A daily diary study on ambidextrous leadership and self‐reported employee innovation
Authors: Zacher Hannes , Wilden Ruth G. 
Published: May 2014

Ambidextrous leadership involves a combination of behaviours that stimulate employee exploration (‘opening behaviour’) and behaviours that facilitate exploitation of ideas (‘closing behaviour’). We hypothesized that the interaction between leaders’ daily opening and closing behaviours (i.e., ambidextrous leadership) predicts employees’ daily self‐reported innovative performance. Results based on diary data provided by 113 employees across five work days supported this hypothesis: daily self‐reported innovative performance was highest when both daily opening and closing behaviours were high.Practitioner points

Findings suggest that selecting and training leaders to engage in ‘opening behaviour’, which stimulates employee exploration, result in higher daily employee innovation.

Leaders should additionally be selected and trained to engage in ‘closing behaviour’, which facilitates exploitation of new ideas, in order to further boost the positive effect of ‘opening behaviour’ on daily employee innovation.
Selected terpenoids from medicinal plants modulate endoplasmic reticulum stress in metabolic disorders
Authors: Beukes Natasha , Levendal Ruby-Ann , Frost Carminita L 
Published: May 2014

Abstract

Objectives
The majority of research performed on cellular stress and apoptosis focuses on mitochondrial dysfunction; however, the importance of the endoplasmic reticulum dysfunction and the link to metabolic diseases has gained a substantial interest. This review focuses on the potential of terpenoids to influence endoplasmic reticulum stress and the possible role terpenoids play as the treatment of metabolic diseases.

Key findings
Metabolic diseases develop as a result of a cascade of cellular pathways. In most cases, cells are able to compensate for the disruption of the cellular homeostasis although the initiation of response pathways; however, chronic stress initiates apoptotic pathways. This reviewed (1) showed the importance of phytoterpenoids to influence endoplasmic reticulum (ER) stress and homeostasis, (2) showed how regulating ER stress affect the cell survival and death, and (3) highlighted some examples of how the progression of metabolic diseases can be influenced by ER.

Summary
Due to the substantial number of terpenoids that have been identified in literature, this review gave examples of 21 terpenoids that have been documented to have an effect on the different proteins associated with ER stress, how these plant terpenoids influence ER dysfunction and metabolic diseases such as diabetes, cancer, liver, and neurological diseases and parasitic infections.