bluuebunny/crossref_metadata_2025 huggingface dataset:
β‐Cell differentiation and regeneration in type 1 diabetes
Authors: Ding L. , Gysemans C. , Mathieu C.
Published: September 2013

Pancreatic insulin‐producing β‐cells have traditionally been viewed as a quiescent cell population. However, several recent lines of evidence indicated that like most tissues the β‐cell mass is dynamically regulated with ongoing β‐cell regeneration throughout life to replenish lost or damaged β‐cells. In type 1 diabetes (T1D), this fine‐tuned balance between β‐cell death and β‐cell renewal in the endocrine pancreas is lost and the deficit in β‐cell mass is largely caused by autoimmune‐mediated apoptosis. Currently, the concept that a cure for T1D will require both re‐establishment of immunological tolerance along with replacement or regeneration of a functional β‐cell mass in T1D patients is generally accepted. In this study our current understanding of the events directing β‐cell replication, β‐cell reprogramming from different cell types and β‐cell regeneration is reviewed, in view of the results of various immunomodulatory strategies aiming at blocking autoimmune responses against pancreatic β‐cells and at improving β‐cell mass and function in subjects with T1D.
Islet autoimmunity in phenotypic type 2 diabetes patients
Authors: Brooks‐Worrell B. , Narla R. , Palmer J. P.
Published: September 2013

Historically, type 2 diabetes (T2D) was considered a metabolic disease of ageing. However, recent discoveries have demonstrated the role of chronic systemic inflammation in the development of insulin resistance and subsequent progression to T2D. Over the years, investigations into the pathophysiology of T2D have identified the presence of islet‐specific T cells and islet autoimmune disease in T2D patients. Moreover, the cell‐mediated islet autoimmunity has also been correlated with the progressive loss of β‐cell function associated with T2D disease pathogenesis. In this manuscript, the involvement of cell‐mediated islet autoimmune disease in the progression of T2D disease and the similarities in islet‐specific T‐cell reactivity between type 1 diabetes (T1D) and T2D are discussed.
NLRP3 and IL‐1β in macrophages as critical regulators of metabolic diseases
Authors: McGettrick A. F. , O'Neill L. A. J.
Published: September 2013

The activation of the NLRP3 inflammasome leads to the autocleavage and activation of caspase‐1. Caspase‐1 cleaves several substrates, including the pro‐inflammatory cytokine IL‐1β. Inflammation, in particular IL‐1β, has long been associated with the progression of metabolic disorders, and recent evidence suggests that the NLRP3 inflammasome plays a critical role in this inflammation. This review concentrates on the activation of NLRP3 during the development of metabolic disorders and the effect this activation has on the inflammatory state as well as the metabolic state of the cell.
An incubation study on the stability and biological effects of pyrogenic and hydrothermal biochar in two soils
Authors: Bamminger C. , Marschner B. , Jüschke E.
Published: September 2013

The success and feasibility of CO2‐sequestration through incorporation of biochar into soils depends strongly on the long‐term biochar stability and on the improvements of physical and microbial soil properties. In this study, the stability of two maize‐derived biochars (from pyrolysis and hydrothermal carbonization) and of a compost‐biochar mixture and their effects on microbial biomass and enzyme activity were determined in two soils during a 57‐day incubation. Soil samples amended with biochar increased soil organic carbon (SOC) content by 20 or 40%. Samples amended with hydrothermal biochar showed the largest respiration rates and the largest increase in microbial and enzymatic activity compared with the untreated controls. Carbon and 13C mass balances showed that between 13 and 16% of the added hydrochar was mineralized within 8 weeks. In the arable soil, hydrochar additions greatly stimulated the degradation of SOC, thus inducing positive priming effects. The mineralization of pyrogenic biochar (pyrochar and a pyrochar‐compost mixture) was significantly less (1.4–3%) and comparable to the SOC mineralization in the control soils.
Codes of Conduct as Private Legal Transplant: The Case of European Extractive MNEs
Authors: Ferrando Tomaso
Published: September 2013

Corporate social responsibility is a dynamic area that cuts across a multitude of disciplines. This paper combines the notion of Corporate Social Responsibility (CSR) with the theory of legal transplant, and claims that Codes of Conduct can be interpreted as proxies of unilateral legal dissemination throughout the entrepreneurial network. By using as example four European extractive Multinational Enterprises (MNEs) (ENI SpA., Total S.A., Repsol YPF, British Petroleum), the article analyses the content of the Codes, the mechanisms and spaces of circulation, and asks questions like whether they are stretching European Union law beyond its traditional boundaries. Exposed to the legal and political relevance of MNEs, the reader is confronted with a global framework characterised by increased complexity, the continuous redefinition of internal and external spaces, deep inconsistencies and unexpressed potential. Therefore, the recognition of the current theoretical weaknesses becomes a fundamental step to critically engage with the production of new legal territories.
Going from One Extreme to the Other: Food Security and Export Restrictions in the EU–CARIFORUM Economic Partnership Agreement
Authors: Gruni Giovanni
Published: September 2013

Between 2007 and 2008, the price of several basic food products spiked suddenly, leaving millions of people without economic access to sufficient food. During the crisis, World Trade Organization (WTO) law was unable to avoid that the use of export restrictions by influential exporting countries jeopardises food security in vulnerable states. A recent trade agreement between the EU and a group of Caribbean countries includes innovative clauses that prohibit export restrictions altogether. This article argues that the prohibition to use export restrictions contained in this agreement is an excessively restrictive solution that does not solve the problems that emerged during the global food crisis. The article concludes with a reflection on the limits of WTO law and the trade policy of the EU with regard to the improvement of food security in vulnerable countries.
Implications of sex‐specific selection for the genetic basis of disease
Authors: Morrow Edward H. , Connallon Tim
Published: September 2013

Mutation and selection are thought to shape the underlying genetic basis of many common human diseases. However, both processes depend on the context in which they occur, such as environment, genetic background, or sex. Sex has widely known effects on phenotypic expression of genotype, but an analysis of how it influences the evolutionary dynamics of disease‐causing variants has not yet been explored. We develop a simple population genetic model of disease susceptibility and evaluate it using a biologically plausible empirically based distribution of fitness effects among contributing mutations. The model predicts that alleles under sex‐differential selection, including sexually antagonistic alleles, will disproportionately contribute to genetic variation for disease predisposition, thereby generating substantial sexual dimorphism in the genetic architecture of complex (polygenic) diseases. This is because such alleles evolve into higher population frequencies for a given effect size, relative to alleles experiencing equally strong purifying selection in both sexes. Our results provide a theoretical justification for expecting a sexually dimorphic genetic basis for variation in complex traits such as disease. Moreover, they suggest that such dimorphism is interesting – not merely something to control for – because it reflects the action of natural selection in molding the evolution of common disease phenotypes.
Continuous digital hypothermia initiated after the onset of lameness prevents lamellar failure in the oligofructose laminitis model
Authors: van Eps A. W. , Pollitt C. C. , Underwood C. , Medina‐Torres C. E. , Goodwin W. A. , Belknap J. K.
Published: September 2013

Reasons for performing study

Prophylactic digital hypothermia reduces the severity of acute laminitis experimentally but there is no evidence for its efficacy as a treatment once lameness has already developed.

Objectives

To investigate the therapeutic effects of digital hypothermia, applied after the onset of lameness, in an experimental acute laminitis model.

Study design

Randomised, controlled (within subject), blinded, experimental trial.

Methods

Eight Standardbred horses underwent laminitis induction using the oligofructose model. Once lameness was detected at the walk, one forelimb was continuously cooled (CRYO), with the other forelimb maintained at ambient temperature (NON‐RX). Dorsal lamellar sections (proximal, middle and distal) harvested 36 h after the onset of lameness/initiation of cryotherapy were analysed by 2 blinded observers: laminitis pathology was scored (0 [normal] to 4 [severe]) and morphometric analyses performed.

Results

Median (interquartile range) histological scores were greater (P<0.05) in NON‐RX (proximal 2.8 [2.5–4]; middle 3.5 [2–4]; distal 2.5 [2–3.8]) compared with CRYO limbs (proximal 0.5 [0.5–1.4]; middle 1 [0.6–1]; distal 0.75 [0.5–1]). There was complete physical separation of lamellar dermis from epidermis (score of 4) in 4 of the NON‐RX feet at one or more section level(s), which was not observed in any CRYO sections. Histomorphometry was thus limited to sections that remained intact; there was a trend of increased total (TELL) and secondary (SELL) epidermal lamellar length and decreased secondary epidermal lamellar width (SELW) in NON‐RX limbs compared with CRYO at all 3 levels; differences were significant (P<0.05) for SELL and SELW in the distal sections.

Conclusions

Digital hypothermia reduced the severity of lamellar injury and prevented lamellar structural failure (complete dermoepidermal separation) when initiated at the detection of lameness in an acute laminitis model. This study provides the first evidence to support the use of therapeutic digital hypothermia as a treatment for acute laminitis.
Do by‐catch reduction devices in longline fisheries reduce capture of sharks and rays? A global meta‐analysis
Authors: Favaro Brett , Côté Isabelle M
Published: September 2013

By‐catch in marine fisheries, particularly those using pelagic and demersal longlines, is a major driver of declines in abundance of sharks and rays around the world. A wide variety of by‐catch reduction devices (BRDs), that is, modified gears designed to reduce incidental captures of a variety of marine species while maintaining target catch rates, have been proposed, but the extent to which BRDs actually reduce the risk of catching sharks and rays remains unclear. We performed a meta‐analysis of 27 publications that reported the capture of sharks and rays and, in some cases, of targeted teleosts in longline gear deployed with and without BRDs. The risk of shark and ray capture differed between types of BRDs, but only one BRD type, longlines raised off the bottom, reduced by‐catch significantly. Circle hooks did not reduce the risk of capturing sharks and rays but might improve discard survival and are inexpensive, which might make them effective in reducing the detrimental effects of longlining on these species. In addition to being generally ineffective, some devices, such as electropositive and magnetic repellents, are expensive and have inherent construction drawbacks that are likely to make them unsuitable for commercial use. Overall, most BRDs did not affect the likelihood of catching targeted teleosts, but a substantial number of studies did not adequately assess target catch. We identified two poorly studied classes of BRD gear (i.e. raised demersal longlines, and monofilament nylon leaders), which represent promising directions for future research.
Fluctuations of perch populations in Lake Geneva from 1984 to 2011 estimated from the number and size of egg strands collected in two locations exposed to different fishing practices
Authors: Gillet C. , Lang C. , Dubois J. P.
Published: September 2013

Fluctuations in the number and size of spawning perch (Perca fluviatilis) in Lake Geneva were evaluated and compared each year from 1984 to 2011 in two locations. This evaluation was based on: (1) each mature female lays only one egg strand per year and (2) the number and size of mature females are well correlated with those of their egg strands. Egg strands were counted and measured at two locations in France and in Switzerland. The collection of egg strands from either artificial substrates (France) or by direct sampling of the natural lake bottom by a diver (Switzerland) did not seem to affect the results. In most years the number and mean width of egg strands fluctuated in the same way in both locations. In addition, yearly perch catches were correlated with the number of egg strands at both locations. However, more small egg strands were found in France than in Switzerland, whereas the reverse was true of large egg strands. Fishing pressure concentrated to a greater extent on small perch in France than in Switzerland could explain this difference.
Riverine and fjord migration of wild and hatchery‐reared Atlantic salmon smolts
Authors: Urke H. A. , Kristensen T. , Ulvund J. B. , Alfredsen J. A.
Published: September 2013

Migration timing, speed, survival and effects of environmental parameters on migration, between wild and hatchery produced Atlantic salmon, Salmo salar L., smolts in the River Lærdalselva were studied. Hatchery‐reared (n = 40) and wild pre‐smolts (n = 40) were tagged with acoustic tags, and an array of receivers along the migration route was deployed. In all, 77 and 85% of the fish from the two groups, respectively, were recorded as migrating smolts, that is, predation rate and/or numbers of fish opting to remain in the river were low. Hatchery‐reared smolts showed a migration pattern, speed and migration route similar to wild smolts, even though the time period between river release and onset of migration was relatively short. Both groups of smolt showed high migration speed through both the river and the fjord compared with other studies.
Ethical Food Consumption and the City
Authors: Pottinger Laura
Published: September 2013

Whilst conceptualisations of ethical or alternative food emphasise places of production, spaces of urban ethical consumption are comparatively under‐theorised. I address this gap by considering ethical consumption in cities alongside ethical consumption of urban space. Attending to the spatiality of ethics in urban food, I examine how ethical consumption practices inflect city identities and how urban spaces shape ideas about being ethical, political or alternative. I draw on three themes: reconnection, ‘place‐frames’ and landscapes of production/consumption, referring to several contemporary urban food initiatives. These include formally accredited ethical places (Fairtrade and ‘Slow’ cities) and creative engagements with urban infrastructure.
Engaging Publics: Biodiversity Data Collection and the Geographies of Citizen Science
Authors: Toogood Mark
Published: September 2013

This article addresses issues surrounding the role of public participation in expert‐driven biodiversity monitoring and research, reviewing a range of cross‐disciplinary insights and critiques that are important for recent debate in environmental geographies. The paper identifies normative, instrumental and substantive motivations dimensions of such initiatives and examines the tensions within these. A key focus concerns the ‘win–win’ model of public participation in scientific research (PPSR); claims of multiple benefits from PPSR, such as increased knowledge of biodiversity issues and of participants’ local environments; claims that doing PPSR is a form of ‘social learning’; and suggestions that engagement in science will change attitudes and environmental behaviour. The ‘win–win’ model is found to veil important issues about the politics of knowledge. These include the framing of citizenship in ‘citizen’ science, the production of certain kinds of scientific subjects within PPSR, the framing of relationships between professional and non‐professional parties, assumptions about the role of ‘data’ in the rational evidenced‐based process and anxieties amongst professional scientists around relations between data quality and the breadth of participation. Whilst the affective engagement with subject and the non‐human world in PPSR is rich and diverse and the expert, non‐expert boundary a mutable one (particularly in natural history), there is increasing contention that the win–win model for PPSR only works if we overlook aspects of these knowledge politics.
Empires of Waste and the Food Security Meme
Authors: Cloke Jon
Published: September 2013

Through a brief review of the literature in which the concept of food security has developed since the first use of the term in 1974, this paper suggests that the ‘food security’ appearing extensively in governmental, official and academic analysis is a social construct that acts to conceal the reality of corporate food production mechanisms dominating global food systems. Since the date of the first World Food Summit in Rome in 1996, representations of both food security and insecurity have increasingly become a meme, a vehicle for conveying and performing a set of socio‐cultural beliefs relating to a neoliberal view of global food production that excludes the biopolitics of corporate, systemic global food production. The analysis focuses particularly on a range of forms of waste produced by global food systems, to suggest that in a world over‐producing food of which over a third is wasted and in which waste has become a mechanism for profit, no presentation of food security that fails to take into account this systemic reality can produce valid or effective policy. The food security meme that has evolved over nearly 40 years portrays at best a partial analysis, which as a consequence continues to proffer a range of market‐based solutions, ignoring issues of dominance and control. In considering the memetic representation of food security, the paper also examines briefly the biopolitics presented by corporate systems of dominance and control in global food production, as well as the systems of waste (vastogenic systems) that they produce. In conclusion, the development of what are effectively empires of waste has fuelled an urgent need for a radical re‐think of food security issues, based on proposals for food regime and food systems analysis that have begun to emerge in the literature.
Opportunities to Build Groundwater Resilience in the Semi‐Arid Tropics
Authors: Garg Kaushal K. , Wani Suhas P.
Published: September 2013

Agricultural water management (AWM) is the adaptation strategy for increasing agricultural production through enhancing water resources availability while maintaining ecosystem services. This study characterizes groundwater hydrology in the Kothapally agricultural watershed, in hard rock Deccan plateau area in India and assesses the impact of AWM interventions on groundwater recharge using a calibrated and validated hydrological model, SWAT, in combination with observed water table data in 62 geo‐referenced open wells. Kothapally receives, on average, 750 mm rainfall (nearly 90% of annual rainfall) during the monsoon season (June to October). Water balance showed that 72% of total rainfall was converted as evapotranspiration (ET), 16% was stored in aquifer, and 8% exported as runoff from the watershed boundary with AWM interventions. Nearly 60% of the runoff harvested by AWM interventions recharged shallow aquifers and rest of the 40% increased ET. Water harvesting structures (WHS) contributed 2.5 m additional head in open wells, whereas hydraulic head under natural condition was 3.5 m, resulting in total 6 m rise in water table during the monsoon. At the field scale, WHSs recharged open wells at a 200 to 400 m spatial scale.
Water Scarcity: Moving Beyond Indexes to Innovative Institutions
Authors: Jarvis W. Todd
Published: September 2013

Water scarcity is a media darling often times described as a trigger of conflict in arid regions, a by‐product of human influences ranging from desertification to climate change, or a combination of natural‐ and human‐induced changes in the water cycle. A multitude of indexes have been developed over the past 20 years to define water scarcity to map the “problem” and guide international donor investment. Few indexes include groundwater within the metrics of “scarcity.” Institutional communication contributes to the recognition of local or regional water scarcity. However, evaluations that neglect groundwater resources may incorrectly define conditions as scarce. In cases where there is a perception of scarcity, the incorporation of groundwater and related storage in aquifers, political willpower, new policy tools, and niche diplomacy often results in a revised status, either reducing or even eliminating the moniker locally. Imaginative conceptualization and innovative uses of aquifers are increasingly used to overcome water scarcity.
Translational Ecology for Hydrogeology
Authors: Schlesinger William H.
Published: September 2013

Translational ecology—a special discipline aimed to improve the accessibility of science to policy makers—will help hydrogeologists contribute to the solution of pressing environmental problems. Patterned after translational medicine, translational ecology is a partnership to ensure that the right science gets done in a timely fashion, so that it can be communicated to those who need it.
When Can Inverted Water Tables Occur Beneath Streams?
Authors: Xie Yueqing , Cook Peter G. , Brunner Philip , Irvine Dylan J. , Simmons Craig T.
Published: September 2013

Decline in regional water tables (RWT) can cause losing streams to disconnect from underlying aquifers. When this occurs, an inverted water table (IWT) will develop beneath the stream, and an unsaturated zone will be present between the IWT and the RWT. The IWT marks the base of the saturated zone beneath the stream. Although a few prior studies have suggested the likelihood of an IWT without a clogging layer, most of them have assumed that a low‐permeability streambed is required to reduce infiltration from surface water to groundwater, and that the IWT only occurs at the bottom of the low‐permeability layer. In this study, we use numerical simulations to show that the development of an IWT beneath an unclogged stream is theoretically possible under steady‐state conditions. For a stream width of 1 m above a homogeneous and isotropic sand aquifer with a 47 m deep RWT (measured in an observation point 20 m away from the center of the stream), an IWT will occur provided that the stream depth is less than a critical value of 4.1 m. This critical stream depth is the maximum water depth in the stream to maintain the occurrence of an IWT. The critical stream depth decreases with stream width. For a stream width of 6 m, the critical stream depth is only 1 mm. Thus while theoretically possible, an IWT is unlikely to occur at steady state without a clogging layer, unless a stream is very narrow or shallow and the RWT is very deep.
Historical Perspectives on Child Sexual Abuse, Part 2
Authors: Smaal Yorick
Published: September 2013

The second part of this article explores some of the topics of inquiry that have preoccupied scholars of child sexual abuse. It begins with feminist considerations of incest and the age of consent before providing a brief historiographical overview of the concept of moral panic as it pertains to offenders and, to a lesser degree, the sexuality of young people. A significant focus is childhood sexuality, including scholarly treatment of juvenile delinquency, and paedophilia, and homosexuality, as well as assumptions underpinning concepts of harm. It concludes by addressing history's potential to inform public debate, including the deliberations of commissions and inquiries before reflecting on the methods, approaches and problems in the field.
Carolingian Catalonia: The Spanish March and the Franks, c.750–c.1050
Authors: Chandler Cullen J.
Published: September 2013

Catalonia is an autonomous community within modern Spain with a distinct history. In the Middle Ages the region became a key component of the Crown of Aragon, and it has attracted a great deal of scholarly attention for its wealth, power, and ‘feudal revolution’. Most historians recognize but do not emphasize the earlier history of the later principality, with roots in the Carolingian period. This article draws attention to the conclusions reached by historians who have built our understanding of Catalonia's early medieval history. The nucleus of the later Catalonia was the Carolingian Spanish March, established as the Franks conquered the territory in the period around 800 CE. The Spanish March functioned as an integral province of the Carolingian Empire, and its leaders, both Franks and locals, played important roles in the dynamics of monarchy in the ninth century. In the tenth century, as Carolingian royal power faded, the locally based leaders of the Spanish March had to find their own ways through trying times. By the beginning of the 11th century, the Carolingian legacy remained intact, even as Frankish royal authority was a thing of the past.
A Crisis of Masculinity? Re‐writing the History of Shell‐shock and Gender in First World War Britain
Authors: Loughran Tracey
Published: September 2013

Shell‐shock is a powerful symbol of the devastating effects of the First World War on men. Until recently, scholars of gender and trauma tended to follow the lines established by Elaine Showalter's interpretation of shell‐shock as a crisis of masculinity. However, over the past decade, historians have investigated different aspects of war trauma and have placed it in different social and cultural contexts. This essay examines recent histories of masculinity and male war experience and discussions of female war trauma and military nursing. It argues that historically and historiographically, shell‐shock has been defined as a masculine illness, and this constitutes a ‘blind spot’ in historical discourse. Historians must explicitly articulate and justify their definitions of war trauma, incorporate the possibility of female trauma into their histories and move beyond gender to explore the multiple contexts within which contemporaries understood trauma.
Pan‐Africanism and the Politics of History
Authors: Onyebuchi Eze Michael
Published: September 2013

Africa is not a country! It is neither a homogenous socio‐cultural group nor a unanimous ethno‐political sovereign. How then could we speak of Pan‐Africanism without generating an ambiguous vernacular mode of identity formation deeply rooted in questionable intellectual claims grounded in politics of history? To make sense of our discourse, therefore, is to localize it within the context of its emergence. These context(s) are the Trans‐Atlantic era and colonial historicity with their associative epochs of subjective domination and shared responses of African peoples to this condition. Among other things, colonialism thrived through a denial of historical culture to non‐Western people(s) with a false promise of “civilizing” the barbarian – a strategy that evacuates all possibility of human enterprise. In Africa and in the African Diaspora, the “uncivilized” is also a non‐historical being of no consequence; an imposed misrecognition that enabled his/her objectification and domination. Pan‐Africanism emerged as a restorative agency in this struggle for freedom and dignity by offering a new pose of repudiation grounded in historical unity of the African experience.
Atomic force microscopic evaluation of nanostructure alterations of rotary NiTi instruments after immersion in irrigating solutions
Authors: Fayyad D. M. , Mahran A. H.
Published: September 2013

Aim

To compare the effect of 5.25% NaOCl or 17% EDTA solutions on the surface topography and roughness of GTX, TF, RaCe and Hero Shaper instruments using atomic force microscopy (AFM) analysis.

Methodology

Four new files of each brand were subjected to AMF analysis; then each group was subdivided into two subgroups (n = 2) in which instruments were immersed in either 5.25% NaOCl or 17% EDTA solutions for 5 min, thereafter subjected to AFM analysis again. Ra and the RMS values were chosen to investigate the surface features of endodontic files.

Results

Before immersion in irrigating solution, TF and Hero Shaper instruments had the significantly highest roughness values and RaCe had the significantly lowest values (P ≤ 0.05). After immersion in NaOCl, GTX and RaCe instruments were not significantly different from the new instruments, nor between them. There was a significant increase in Ra and RMS values for TF and Hero Shaper instruments over that of untreated ones and that of GTX and RaCe instruments. No significant increase in surface roughness of the instruments was recorded with EDTA.

Conclusion

17% EDTA did not significantly affect the surface roughness of the instruments, whilst 5.25% NaOCl increased the surface roughness of TF and Hero Shaper significantly more than that of RaCe and GTX instruments.
HLA and disease: guilt by association
Authors: Howell W. M.
Published: September 2013

It is now over forty years since the first associations between particular HLA antigens and disease susceptibility were described, and the identification of large numbers HLA‐associated diseases parallels our increased understanding of the genetic complexity of the HLA system and its extensive polymorphism. However, surprisingly and frustratingly, clear identification of the underlying mechanisms resulting in a causative role for HLA polymorphism in the molecular immunopathogenesis of individual HLA‐associated diseases remains the exception rather than the rule. This review, while not intended to be a comprehensive catalogue of HLA‐associated diseases, aims to revisit a number of well known and more recently described HLA‐associated diseases as exemplars of our current understanding of the underlying molecular mechanisms which may result in genetic disease predisposition. Such mechanisms may act as pointers for further investigations in other HLA‐associated diseases. The clinical utility of specific HLA disease associations in disease diagnosis/exclusion is also considered.
Elephant behaviour in a semi‐arid environment*
Authors: BARNES R. F. W.
Published: September 2013

Elephants were observed for two dry seasons and the intervening wet season in Ruaha National Park, Tanzania. The behaviour of cows was influenced to a greater extent by weather than was the behaviour of bulls. Variations in bulls' ranging behaviour could be explained by the proportion of the bull population that was sexually active at any particular time of year.

In the mid dry season, when there was very little food available, bulls moved short distances each day, while cows travelled long distances in search of food for themselves and their dependent offspring. Later in the dry season the benefits of long day ranges were outweighed by increasing juvenile mortality.

Des éléphants ont été observés durant deux saisons sèches et la saison des pluies intermédiaire, au Ruaha N.P. en Tanzanie. Le comportement des femelles est plus influencé par le temps que celui des mâles. Les variations dans le comportement des mâles pourraient être expliquées par la proportion de la population des mâles sexuellement active à chaque moment précis de l'année.

Au milieu de la saison sèche, quand il y a peu de nourriture disponible, les mâles parcourent de courtes distances chaque jour alors que les femelles couvrent de longs trajets à la recherche de nourriture pour elles‐mêmes et leur progéniture. Plus tard dans la saison sèche, les bénéfices de longs déplacements sont contrebalancés par l'augmentation de la mortalité juvénile.
Spatial and temporal variability in species richness in a temperate intertidal community
Authors: de Juan S. , Hewitt J.
Published: September 2013

Understanding changes in estuarine benthic communities has important implications for conservation and yet it is a challenge due to the high natural variability of these systems. We addressed this challenge through the study of temporal and spatial patterns of species richness in an intertidal benthic community in New Zealand North Island. Five different locations within the estuary were monitored seasonally over 12 yr. This data set allowed the study of species–time–area relationships (STAR) and the delineation of patterns in species richness, heterogeneity and turnover in space and time. The site with the highest species richness also had the highest within‐site heterogeneity in species richness, a high number of species occurring infrequently in time, the lowest mud content and the most variable wave climate. Similarities and differences between sites were generally maintained over time, although seasonal and multi‐year patterns in species richness occurred at all sites. The STAR showed a significant negative interaction between space and time, with species accumulation rates in space and time being equivalent at 4 spatial replicates (250 m2) and 2 temporal replicates (6 months). The lowest source of variability in species turnover was within site, and the highest source was over years. This was reflected in the lack of an asymptotic relationship in the species accumulation curve despite the 12 yr of monitoring. These results contribute to the knowledge of the variability in diversity patterns in estuaries and have important implications for long‐term monitoring of natural communities and the estimation of diversity for conservation.
Where is positional uncertainty a problem for species distribution modelling?
Authors: Naimi Babak , Hamm Nicholas A. S. , Groen Thomas A. , Skidmore Andrew K. , Toxopeus Albertus G.
Published: September 2013

Species data held in museum and herbaria, survey data and opportunistically observed data are a substantial information resource. A key challenge in using these data is the uncertainty about where an observation is located. This is important when the data are used for species distribution modelling (SDM), because the coordinates are used to extract the environmental variables and thus, positional error may lead to inaccurate estimation of the species–environment relationship. The magnitude of this effect is related to the level of spatial autocorrelation in the environmental variables. Using local spatial association can be relevant because it can lead to the identification of the specific occurrence records that cause the largest drop in SDM accuracy. Therefore, in this study, we tested whether the SDM predictions are more affected by positional uncertainty originating from locations that have lower local spatial association in their predictors. We performed this experiment for Spain and the Netherlands, using simulated datasets derived from well known species distribution models (SDMs). We used the K statistic to quantify the local spatial association in the predictors at each species occurrence location. A probabilistic approach using Monte Carlo simulations was employed to introduce the error in the species locations. The results revealed that positional uncertainty in species occurrence data at locations with low local spatial association in predictors reduced the prediction accuracy of the SDMs. We propose that local spatial association is a way to identify the species occurrence records that require treatment for positional uncertainty. We also developed and present a tool in the R environment to target observations that are likely to create error in the output from SDMs as a result of positional uncertainty.
ModestR: a software tool for managing and analyzing species distribution map databases
Authors: García‐Roselló Emilio , Guisande Cástor , González‐Dacosta Jacinto , Heine Juergen , Pelayo‐Villamil Patricia , Manjarrás‐Hernández Ana , Vaamonde Antonio , Granado‐Lorencio Carlos
Published: September 2013

The ModestR package consists of three applications: MapMaker, DataManager and MRFinder. MapMaker facilitates making range maps by drawing the areas, by importing existing data or using the Global Biodiversity Information Facility portal. It can discriminate between different habitats, thereby making data cleaning tasks easier. DataManager allows the management of taxonomically structured databases for range maps. MRFinder supports querying ModestR databases to find the species present in specific areas. Possible applications include the compilation and management of species distribution databases, cleaning data and computing aggregated data to perform subsequent analyses in other packages thanks to emphasized interoperability.
Inferring the similarity of species distributions using Species’ Distribution Models
Authors: Godsoe William
Published: September 2013

A common problem in ecology is our need to reliably compare information on the distributions of distinct species. Since it is not always possible to directly compare the distributions of two species, numerous papers now seek to compare the predictions of Species’ Distribution Models (SDMs, estimates of the probability that two species are present, given environmental data). At present, it is not clear when these analyses of SDMs actually reproduce comparisons of species’ distributions. I use analytic results and simulations to show that even if the SDMs for two species are identical; their distributions may still differ dramatically. I use this problem to motivate a new index to compare SDMs – an estimate of the Sørensen's similarity of the distributions of two species. I then provide a script to compute this estimator in R. Using simulations I show that this estimator provides a much stronger inference of the similarity of species distributions than previously proposed methods. This work clarifies the interpretation of comparisons of SDMs.
Planar Solid Oxide Fuel Cells Using PSZ, Processed by Sequential Aqueous Tape Casting and Constrained Sintering
Authors: Aguilar‐Arias Jaime , Hotza Dachamir , Lenormand Pascal , Ansart Florence
Published: September 2013

A process for obtaining planar anode‐supported solid oxide fuel cells was developed. Aqueous‐based slurries were prepared and sequentially deposited via tape casting to form half cell tapes consisting of the electrolyte, functional, and structural anode. Sintering of the three‐layered tapes was done in two stages: presintering circular samples of 25 mm diameter in free conditions first, and then sintering them using zirconium disks as light loads (90 Pa), to obtain half cells having 20 mm and 3.8 m−1 in diameter and curvature, respectively. Active materials for the electrolyte, anode, and cathode were partially stabilized zirconia (PSZ), Ni and LSM, respectively. Finally, thicknesses of complete cells were 400, 30, 30, and 80 μm for the structural anode, functional anode, electrolyte, and cathode, respectively. The cells were tested in a no‐chamber (direct‐flame) setup evaluating electrochemical performance and shock thermal resistance. Open circuit voltage was 830 mV at 560°C using methanol as fuel in a burner with porous media to modify the shape of the flame. Cells were also strong enough to resist the rapid temperature changes during several no‐chamber tests.
Solution Synthesis of BiFeO3 Thin Films onto Silicon Substrates with Ferroelectric, Magnetic, and Optical Functionalities
Authors: Gutiérrez‐Lázaro Carmen , Bretos Iñigo , Jiménez Ricardo , Ricote Jesús , Hosiny Hitham El , Pérez‐Mezcua Dulce , Jiménez Rioboó Rafael J. , García‐Hernández Mar , Calzada Maria L.
Published: September 2013

Single‐BiFeO3 perovskite films onto Pt‐coated silicon substrates have been fabricated by chemical solution deposition using a synthesis strategy based on the use of nonhazardous reagents. Different routes were tested to obtain precursors for the deposition of the films, inferring that bismuth (III) nitrate and iron (III) 2,4‐pentanedionate dissolved in acetic acid and 1,3‐propendiol led to the best solution. Ferroelectric, magnetic, and optical functionalities were demonstrated in these films, obtaining a high ferroelectric polarization at room temperature, ~67 μC × cm−2, a dependence of the magnetization with the film thickness, 0.60 and 2.50 emu × g−1 for the ~215 and ~42‐nm‐thick films, and a direct band gap in the visible range, Eg ~2.82 eV. These results support the interest of solution methods for the fabrication of BiFeO3 thin films onto the silicon substrates required in microelectronic devices.
Transparent ZnS Ceramics by Sintering of High Purity Monodisperse Nanopowders
Authors: Chlique Christophe , Merdrignac‐Conanec Odile , Hakmeh Noha , Zhang Xianghua , Adam Jean‐Luc
Published: September 2013

We report an efficient way of preparing transparent ZnS ceramics using the hot‐pressing technique. It has been found that the transparency is highly dependent on the purity and the grain size distribution of the starting ZnS powders. Highly pure and monodisperse ZnS powders have been obtained by posttreatment of the precipitated powders in a H2S/N2 flow for 2 h at 600°C. The obtained ZnS ceramics show fully dense and homogeneous microstructure with average grain size of ~1 μm and smooth grain boundaries, leading to an excellent transmission of around 70% in the mid‐ and far‐ IR regions. The preparation technique described in this study is highly reproducible.
The moderating role of emotional competence in suicidal ideation among Chinese university students
Authors: Kwok Sylvia Y.C.L.
Published: September 2013

Aims

To explore the relationship among perceived family functioning, emotional competence and suicidal ideation and to examine the moderating role of emotional competence in suicidal ideation.

Background

Previous studies have highlighted that poor family relationships and emotional symptoms are significant predictors of suicidal ideation. However, the roles of perceived family functioning and emotional competence in predicting suicidal ideation have not been given adequate attention.

Design

A cross‐sectional survey using convenience sampling.

Method

A questionnaire was administered to 302 university students from February–April in 2011 in Hong Kong. The means, standard deviations and Cronbach's alphas of the variables were computed. Pearson correlation analyses and hierarchical regression analyses were performed.

Results

Hierarchical regression analyses showed that perceived high family functioning and emotional competence were significant negative predictors of suicidal ideation. Further analyses showed that parental concern, parental control and creative use of emotions were significant predictors of suicidal ideation. Emotional competence, specifically creative use of emotions, was found to moderate the relationship between perceived family functioning and suicidal ideation.

Conclusion

The findings support the family ecological framework and provide evidence for emotional competence as a resilience factor that buffers low family functioning on suicidal ideation. Suggested measures to decrease suicidal ideation include enhancing parental concern, lessening parental control, developing students' awareness, regulation and management of their own emotions, fostering empathy towards others' emotional expression, enhancing social skills in sharing and influencing others' emotions and increasing the positive use of emotions for the evaluation and generation of new ideas.
Development of the Chesapeake Bay Watershed Total Maximum Daily Load Allocation
Authors: Linker Lewis C. , Batiuk Richard A. , Shenk Gary W. , Cerco Carl F.
Published: September 2013

Nutrient load allocations and subsequent reductions in total nitrogen and phosphorus have been applied in the Chesapeake watershed since 1992 to reduce hypoxia and to restore living resources. In 2010, sediment allocations were established to augment nutrient allocations supporting the submerged aquatic vegetation resource. From the initial introduction of nutrient allocations in 1992 to the present, the allocations have become more completely applied to all areas and loads in the watershed and have also become more rigorously assessed and tracked. The latest 2010 application of nutrient and sediment allocations were made as part of the Chesapeake Bay total maximum daily load and covered all six states of the Chesapeake watershed. A quantitative allocation process was developed that applied principles of equity and efficiency in the watershed, while achieving all tidal water quality standards through an assessment of equitable levels of effort in reducing nutrients and sediments. The level of effort was determined through application of two key watershed scenarios: one where no action was taken in nutrient control and one where maximum nutrient control efforts were applied. Once the level of effort was determined for different jurisdictions, the overall load reduction was set watershed‐wide to achieve dissolved oxygen water quality standards. Further adjustments were made to the allocation to achieve the James River chlorophyll‐a standard.
Deriving Chesapeake Bay Water Quality Standards
Authors: Tango Peter J. , Batiuk Richard A.
Published: September 2013

Achieving and maintaining the water quality conditions necessary to protect the aquatic living resources of the Chesapeake Bay and its tidal tributaries has required a foundation of quantifiable water quality criteria. Quantitative criteria serve as a critical basis for assessing the attainment of designated uses and measuring progress toward meeting water quality goals of the Chesapeake Bay Program partnership. In 1987, the Chesapeake Bay Program partnership committed to defining the water quality conditions necessary to protect aquatic living resources. Under section 303(c) of the Clean Water Act, States and authorized tribes have the primary responsibility for adopting water quality standards into law or regulation. The Chesapeake Bay Program partnership worked with U.S. Environmental Protection Agency to develop and publish a guidance framework of ambient water quality criteria with designated uses and assessment procedures for dissolved oxygen, water clarity, and chlorophyll a for Chesapeake Bay and its tidal tributaries in 2003. This article reviews the derivation of the water quality criteria, criteria assessment protocols, designated use boundaries, and their refinements published in six addendum documents since 2003 and successfully adopted into each jurisdiction's water quality standards used in developing the Chesapeake Bay Total Maximum Daily Load.
Computing Atmospheric Nutrient Loads to the Chesapeake Bay Watershed and Tidal Waters
Authors: Linker Lewis C. , Dennis Robin , Shenk Gary W. , Batiuk Richard A. , Grimm Jeffrey , Wang Ping
Published: September 2013

Application of integrated Chesapeake Bay models of the airshed, watershed, and estuary support air and water nitrogen controls in the Chesapeake. The models include an airshed model of the Mid‐Atlantic region which tracks the estimated atmospheric deposition loads of nitrogen to the watershed, tidal Bay, and adjacent coastal ocean. The three integrated models allow tracking of the transport and fate of nitrogen air emissions, including deposition in the Chesapeake watershed, the subsequent uptake, transformation, and transport to Bay tidal waters, and their ultimate influence on Chesapeake water quality. This article describes the development of the airshed model, its application to scenarios supporting the Chesapeake Total Maximum Daily Load (TMDL), and key findings from the scenarios. Key findings are that the atmospheric deposition loads are among the largest input loads of nitrogen in the watershed, and that the indirect nitrogen deposition loads to the watershed, which are subsequently delivered to the Bay are larger than the direct loads of atmospheric nitrogen deposition to Chesapeake tidal waters. Atmospheric deposition loads of nitrogen deposited in coastal waters, which are exchanged with the Chesapeake, are also estimated. About half the atmospheric deposition loads of nitrogen originate from outside the Chesapeake watershed. For the first time in a TMDL, the loads of atmospheric nitrogen deposition are an explicit part of the TMDL load reductions.