Phenomenological Study of Middle School Teacher Practices Regarding Homework in an Eastern North Carolina Rural Community

This study was an investigation of homework practices at the middle school level. For this phenomenological study, 48 certified middle school teachers in an eastern North Carolina rural community provided insight about homework at the middle school level by participating in a survey. The debate about homework is ongoing and often evokes a variety of passionate responses from those on both sides of the debate. The findings in this study revealed a spectrum of homework practices throughout the five middle schools. Homework is the most widely used instructional practice, yet one that is rarely reflected upon by teachers, administrators, and district leaders. In order to support learning, teachers need to make the time to review research-based practices in order to determine implications on their own classroom practices and then apply these practices to their current instruction to ensure homework plays a beneficial role in the learning process for students. Based on the findings, this study provided research for further studies and implication for practice for district leaders, administrators, and teachers

The New World of Pet Prosthetics

When an abandoned dog was found in Brooklyn with his paw gnawed off, the animal shelter had two options: amputate the leg, or put the dog down. But neither seemed like a solution. So they decided to do something different, and fit the dog for a prosthetic leg. Prosthetics for people have been around for millennia, and now these devices are moving into the animal kingdom. This story explores the new world of animal prosthetics, and how these devices have changed the lives of animals like Mr. Stubbs — the first alligator with a prosthetic tail — and saved the life of a dog named Buddy. Link to full story: https://abroo870.wixsite.com/animalprosthetic

Paternal Care in Collared Lemmings (Dicrostonyx richardsoni): Artifact or Adaptation?

Experiments conducted in large enclosures using 13 pairs of collared lemmings (Dicrostonyx richardsoni) and their pups examined the effects of three different treatments on paternal care. Treatments tested whether males altered their attentiveness to the pups when certainty of paternity was in question (through presence of a strange male), when alternative activities were available (through access to a running wheel), and when both factors were present simultaneously. Males covered and groomed pups equally among treatments. During the first five days of observation, males with access to a running wheel paid significantly less attention to strange males relative to males without access to a running wheel. Continuous exposure to the strange male may have been responsible for this short-term effect. Since covering and grooming of pups were unaffected by the presence of a strange male, the fathers' perceptions of their certainty of paternity were probably unaffected. Maintenance of paternal care under different conditions and in large enclosures provides further evidence that paternal care is not an artifact of laboratory conditions. Paternal care in collared lemmings may have evolved to maximize fitness of both sexes during winter.Key words: collared lemming, paternal care, winter breeding, fitnessDes expériences menées dans de grands enclos, et mettant en jeu 13 couples de lemmings à collerette (Dicrostonyx richardsonii) et leurs petits, évaluaient les effets de 3 traitements différents sur les soins paternels. Ces traitements vérifiaient si les mâles modifiaient l'attention qu'ils portaient à leurs petits lorsque leur paternité était mise en doute (par la présence d'un mâle étranger), lorsque d'autres activités étaient disponibles (par l'accès à une roue d'exercice), et lorsque ces 2 facteurs étaient présents en même temps. Les mâles protégeaient leurs petits et les nettoyaient de la même façon lors des différents traitements. Au cours des 5 premiers jours d'observation, les mâles qui avaient accès à une roue d'exercice prêtaient nettement moins attention aux mâles étrangers, comparativement aux mâles qui n'avaient pas accès à une roue. L'exposition continue au mâle étranger peut expliquer cet effet à court terme. Vu que les soins visant à protéger et à nettoyer les petits n'étaient pas affectés par la présence d'un mâle étranger, la perception qu'avaient les pères quant à la certitude de leur paternité n'était probablement pas affectée. Le maintien des soins paternels dans différentes conditions et à l'intérieur de grands enclos offre une preuve supplémentaire à l'appui que ces soins ne sont pas créés par les conditions de laboratoire. Les soins paternels chez le lemming à collerette ont peut-être évolué afin de maximiser la santé physique des 2 sexes en période hivernale.Mots clés : lemming à collerette, soins paternels, reproduction hivernale, santé physiqu

Direct selection on male attractiveness and female preference fails to produce a response

BACKGROUND: Theoretical studies suggest that direct and indirect selection have the potential to cause substantial evolutionary change in female mate choice. Similarly, sexual selection is considered a strong force in the evolution of male attractiveness and the exaggeration of secondary sexual traits. Few studies have, however, directly tested how female mate choice and male attractiveness respond to selection. Here we report the results of a selection experiment in which we selected directly on female mating preference for attractive males and, independently, on male attractiveness in the guppy, Poecilia reticulata. We measured the direct and correlated responses of female mate choice and male attractiveness to selection and the correlated responses of male ornamental traits, female fecundity and adult male and female survival. RESULTS: Surprisingly, neither female mate choice nor male attractiveness responded significantly to direct or to indirect selection. Fecundity did differ significantly among lines in a way that suggests a possible sexually-antagonistic cost to male attractiveness. CONCLUSIONS: The opportunity for evolutionary change in female mate choice and male attractiveness may be much smaller than predicted by current theory, and may thus have important consequences for how we understand the evolution of female mate choice and male attractiveness. We discuss a number of factors that may have constrained the response of female choice and male attractiveness to selection, including low heritabilities, low levels of genetic (co)variation in the multivariate direction of selection, sexually-antagonistic constraint on sexual selection and the "environmental covariance hypothesis"

Reconstructing and understanding the impacts of storms and surges, southern North Sea

Coastal barriers are ubiquitous globally and provide a vital protective role to valuable landforms, habitats and communities located to landward. They are, however, vulnerable to extreme water levels and storm wave impacts. A detailed record of sub-annual to annual; decadal; and centennial rates of shoreline retreat in frontages characterized by both high (> 3 m) and low (< 1 m) dunes is established for a barrier island on the UK east coast. For four storms (2006–2013) we match still water levels and peak significant wave heights against shoreline change at high levels of spatial densification. The results suggest that, at least in the short-term, shoreline retreat, of typically 5–8 m, is primarily driven by individual events, separated by varying periods of barrier stasis. Over decadal timescales, significant inter-decadal changes can be seen in both barrier onshore retreat rates and in barrier extension rates alongshore. Whilst the alongshore variability in barrier migration seen in the short-term remains at the decadal scale, shoreline change at the centennial stage shows little alongshore variability between a region of barrier retreat (at 1.15 m a$^{−1}$) and one of barrier extension. A data-mining approach, synchronizing all the variables that drive shoreline change (still water level, timing of high spring tides and peak significant wave heights), is an essential requirement for validating models that predict future shoreline responses under changing sea level and storminess.This paper was completed while the first author (SB) was a recipient of a Leverhulme Research Fellowship (RF-2015-045) for a project entitled Development and Application of a shoreline response model. This paper is a contribution to NERC BESS Consortium grant A hierarchical approach to the examination of the relationship between biodiversity and ecosystem service flows across coastal margins (grant reference NE/J015423/1). Table 1 reports information gathered as part of an EU FP7 Collaborative Project (grant agreement no: 603458) Resilience-Increasing Strategies for Coasts – toolkit (http://www.risckit.eu).This is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1002/esp.390

Thrombin is a novel regulator of hexokinase activity in mesangial cells

Thrombin is a novel regulator of hexokinase activity in mesangial cells.BackgroundHexokinase (HK) activity is fundamentally important to cellular glucose uptake and metabolism. Phorbol esters increase both HK activity and glucose utilization in cultured mesangial cells via a protein kinase C (PKC)- and extracellular signal-regulated kinases 1 and 2 (ERK1/2)-dependent mechanism. In adult kidneys, increased HK activity has been reported in both glomerular injury and in diabetes, but the mechanisms responsible for these changes are unknown. Thrombin, a known activator of both PKC and ERK1/2, is increased in the settings of renal injury and diabetes. Thus, thrombin may contribute to the observed changes in HK activity in vivo.MethodsThrombin and thrombin receptor agonists were tested for the ability to increase HK activity and glucose metabolism in murine mesangial (SV40 MES 13) cells. ERK1/2 activation was also evaluated in parallel. Thrombin inhibition (hirudins), PKC depletion, Ser-Thr kinase inhibition (H-7), MEK1/2 inhibition (PD98059), pertussis toxin (PTX), and general inhibitors of transcription or translation were then tested for the ability to attenuate these effects.ResultsThrombin (≥0.01 U/mL) mimicked the effect of phorbol esters, increasing HK activity 50% within 12 to 24 hours (P < 0.05). This effect was inhibited by hirudins, mimicked by thrombin receptor agonists, and accompanied by increased Glc utilization. H-7, PD98059, and general inhibitors of transcription or translation—but not PTX—prevented thrombin-induced HK activity at 24 hours. PKC depletion and PD98059 also blocked the associated phosphorylation and activation of ERK1/2.ConclusionsThrombin increases mesangial cell HK activity via a PTX-insensitive mechanism involving thrombin receptor activation, PKC-dependent activation of ERK1/2, and both ongoing gene transcription and de novo protein synthesis. As such, thrombin is a novel regulator of HK activity in mesangial cells and may play a role in coupling renal injury to metabolism

Composition dependent electrochemical properties of earth-abundant ternary nitride anodes

Growing energy storage demands on lithium-ion batteries necessitate exploration of new electrochemical materials as next-generation battery electrode materials. In this work, we investigate the previously unexplored electrochemical properties of earth-abundant and tunable Zn1-xSn1+xN2 (x = -0.4 to x = 0.4) thin films, which show high electrical conductivity and high gravimetric capacity for Li insertion. Enhanced cycling performance is achieved compared to previously published end-members Zn3N2 and Sn3N4, showing decreased irreversible loss and increased total capacity and cycle stability. The average reversible capacity observed is > 1050 mAh/g for all compositions and 1220 mAh/g for Zn-poor (x = 0.2) films. Extremely Zn-rich films (x = -0.4) show improved adhesion; however, Zn-rich films undergo a phase transformation on the first cycle. Zn-poor and stoichiometric films do not exhibit significant phase transformations which often plague nitride materials and show no required overpotential at the 0.5 V plateau. Cation composition x is explored as a mechanism for tuning relevant mechanical and electrochemical properties, such as capacity, overpotential, phase transformation, electrical conductivity, and adhesion. The lithiation/delithiation experiments confirm the reversible electrochemical reactions. Without any binding additives, the as-deposited electrodes delaminate resulting in fast capacity degradation. We demonstrate the mechanical nature of this degradation through decreased electrode thinning, resulting in cells with improved cycling stability due to increased mechanical stability. Combining composition and electrochemical analysis, this work demonstrates for the first time composition dependent electrochemical properties for the ternary Zn1-xSn1+xN2 and proposes earth-abundant ternary nitride anodes for increased reversible capacity and cycling stability

Gender Differences Concerning Physical Activity Beliefs and Practices among Fourth and Fifth Graders in Rural Virginia

Cardiovascular disease is the leading cause of death in the United States. Physical activity (PA) is a known preventative factor. It is recommended that children participate in 60 minutes of PA daily, but most do not meet these guidelines. Further, boys, aged 8-17 years, spend more time in PA than girls of the same age. The purposes of this study were to identify gender differences in PA beliefs and practices among fourth and fifth graders and to determine when gender disparities in self-confidence regarding PA and fitness occur.&nbsp; Subjects were 41 fourth (19 boys; 22 girls) and 33 fifth (16 boys; 17 girls) graders in a public elementary school in the rural northwest. They participated in the FitnessGram, a nationwide assessment of flexibility, aerobic capacity, and muscular strength and endurance, and a proctored survey about their PA beliefs, self-confidence, and participation. There were no differences in FitnessGram data between boys and girls for aerobic capacity or muscular strength and endurance, but girls had increased flexibility when compared to boys in both grades. Importantly, survey results showed fifth grade girls had less confidence they could improve their physical fitness (p = 0.002) or their overall health (p = 0.004) when compared to fourth grade girls. Research is needed to determine how these changes in self-confidence contribute to the gender gap in time spent in PA. We recommend physical education programs throughout all grades teach healthy behaviors, including time spent in PA, and work to build and maintain self-confidence in girls