bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of Bioactive Potential of an Aloe vera Sterol Extract
Authors: Bawankar Raksha , Deepti V. C. , Singh Pooja , Subashkumar Rathinasamy , Vivekanandhan Govindasamy , Babu Subramanian
Published: August 2012

We prepared a crude gel material from Aloe vera succulent leaf tissues. The ethanolic extract of lyophilized A. vera gel was used for the GC‐MS analysis. Hexadecanoic acid (22.22%) was identified as major compound. Sitosterol and stigmasterol were found to be 2.89% and 2.1% in the extract. HPLC analysis was carried out to confirm the presence of stigmasterol. The concentration of sterol extract needed to scavenge DPPH free radical by 50% was calculated as 5.2 mg mL−1. In the FRAP assay, the sterol extract showed significant hydroxyl radical scavenging in a dose‐dependent manner (IC50 value 1.17 µg mL−1). Concentration of the sample required to reduce lipid peroxidation was found to be 4.18 µg mL−1, and the extract also possessed acetylcholinesterase activity (IC50 ‐ 5.26 µg mL−1). Catalase activity was 0.196 μM H2O2 decomposed min−1 µg−1 protein, whereas the peroxidase activity was 17.01 μM of pyragallol oxidized min−1 µg−1 protein. The extract recorded higher activity against growth of S. greseus and C. albicans in the experiments carried out to determine antibacterial and antifungal activity, respectively. Copyright © 2012 John Wiley & Sons, Ltd.
The Effect of Applied Electric Field on the Diameter and Size Distribution of Electrospun Nylon6 Nanofibers
Authors: Sohrabi Amirreza , Shaibani Parmiss Mojir , Thundat Thomas
Published: August 2012

One‐dimensional Nylon6 nanofibers were fabricated through the electrospinning process. The effect of the applied electric field and voltage–distance combinations on the diameter and size distribution of the fibers was examined systematically by analyzing scanning electron microscopy (SEM) images. The results indicated that maintaining the electric field at 1 kV/cm with the voltage–distance combination of 15 kV–15 cm among all other combinations would result in the optimum average diameter as well as a narrow size distribution of the fibers. SCANNING 35: 183‐188, 2013. © 2012 Wiley Periodicals, Inc.
Runx3 Protects Gastric Epithelial Cells Against Epithelial-Mesenchymal Transition-Induced Cellular Plasticity and Tumorigenicity
Authors: Voon Dominic Chih-Cheng , Wang Huajing , Koo Jason Kin Wai , Nguyen Tu Anh Pham , Hor Yit Teng , Chu Yeh-Shiu , Ito Kosei , Fukamachi Hiroshi , Chan Shing Leng , Thiery Jean Paul , Ito Yoshiaki
Published: August 2012

The transcription factor RUNX3 functions as a tumor suppressor in the gastrointestinal epithelium, where its loss is an early event in carcinogenesis. While RUNX3 acts concurrently as a mediator of TGF-β signaling and an antagonist of Wnt, the cellular changes that follow its loss and their contribution to tumorigenicity are not fully understood. Here, we report that the loss of Runx3 in gastric epithelial cells results in spontaneous epithelial-mesenchymal transition (EMT). This produces a tumorigenic stem cell-like subpopulation, which remarkably expresses the gastric stem cell marker Lgr5. This phenomenon is due to the compounding effects of the dysregulation of the TGF-β and Wnt pathways. Specifically, Runx3−/−p53−/− gastric epithelial cells were unexpectedly sensitized for TGF-β-induced EMT, during which the resultant induction of Lgr5 was enhanced by an aberrantly activated Wnt pathway. These data demonstrate a protective role for RUNX3 in safeguarding gastric epithelial cells against aberrant growth factor signaling and the resultant cellular plasticity and stemness.
A shRNA Functional Screen Reveals Nme6 and Nme7 Are Crucial for Embryonic Stem Cell Renewal
Authors: Wang Chia-Hui , Ma Nianhan , Lin Yu-Tsen , Wu Cheng-Chung , Hsiao Michael , Lu Frank Leigh , Yu Ching-Chia , Chen Shao-Yin , Lu Jean
Published: August 2012

In contrast to the somatic cells, embryonic stem cells (ESCs) are characterized by its immortalization ability, pluripotency, and oncogenicity. Revealing the underlying mechanism of ESC characteristics is important for the application of ESCs in clinical medicine. We performed systematic functional screen in mouse ESCs with 4,801 shRNAs that target 929 kinases and phosphatases. One hundred and thirty-two candidate genes that regulate both ESC expansion and stem cell marker expression were identified. Twenty-seven out of the 132 genes were regarded as most important since knockdown of each gene induces morphological changes from undifferentiated to differentiated state. Among the 27 genes, we chose nonmetastatic cell 6 (Nme6, also named as Nm23-H6) and nonmetastatic cell 7 (Nme7, also designated as Nm23-H7) to study first. Nme6 and Nme7 both belong to the members of nucleoside diphosphate kinase family. We demonstrate that Nme6 and Nme7 are important for the regulation of Oct4, Nanog, Klf4, c-Myc, telomerase, Dnmt3B, Sox2, and ERas expression. Either knockdown of Nme6 or Nme7 reduces the formation of embryoid body (EB) and teratoma. The overexpression of either Nme6 or Nme7 can rescue the stem cell marker expression and the EB formation in the absence of leukemia inhibiting factor. This implies the importance of Nme6 and Nme7 in ESC renewal. This finding not only pinpoints Nme6 or Nme7 can regulate several critical regulators in ESC renewal but also increases our understanding of the ESC renewal and oncogenesis.
Principles of nutrient management for sustainable forest bioenergy production
Authors: Mead Donald , Smith Charles
Published: August 2012

Nutrient management is an important part of ensuring sustainable forest production. Essential concepts for managing site nutrients are built on the knowledge of types of soil, tree nutrient demands, and how these are impacted by silviculture, harvesting, and other management practices. Managers must clearly define forest management objectives, and how bioenergy production or carbon dioxide‐offset objectives require special consideration. Managers must examine how silviculture, harvesting, and other management practices might affect nutrient pools and availability. Soil fertility management practices are designed in response to these evaluation steps. Fertility management alternatives may include altering management practices that affect the distribution of harvested tree branches, foliage, and tops, as well as addition of fertilizers, nitrogen‐fixing plants, or wood ash. Planting on sites with pre‐existing nutrient deficiencies may require adding nutrients to obtain merchantable tree growth over the short and long term. Nutrient management principles may also be required to minimize off‐site impacts of management practices, for example, on water quality or climate change. Managers must determine what nutrients are needed on forested sites, amendment rates, and timing, and take into account the relationships among nutrients, soil, climate, and plant processes throughout the rotation. Soil and foliar analysis and the use of soil and plant bioassay tools can assist in these evaluations. Sustainable management practices require that nutrient control strategies evaluate economic and energy balances, and if necessary, modify management practices, including nutrient amendments, to ensure that they are sustainable. Examples of forest nutrient management practices are described.

This article is categorized under:

Bioenergy > Systems and Infrastructure

Energy and Development > Science and Materials

Energy and Development > Economics and Policy

Energy and Development > Climate and Environment
Opportunities and barriers of high‐voltage direct current grids: a state of the art analysis
Authors: Coll‐Mayor Debora , Schmid Jürgen
Published: August 2012

Limiting the consequences of the climate change means that global CO2 emissions are to be reduced very rapidly. Taking into account that the expected economic growth of developing countries will inevitably be accompanied by a further growth in emissions in these countries, there is a strong necessity that the energy systems in the industrialized world be transformed into emission‐free ones. This level of reduction requires, for example, that the European Union achieves a ‘nearly zero‐carbon power supply’, involving replacing of fossil fuels in most or all buildings and much of the transport sector by nearly zero‐carbon electricity. It is also clear that the current political framework is, especially in Europe, propitiating the large‐scale implementation of renewable energy sources. In order to make this large implementation economically feasible, it is essential that the potential of these sources is maximized, placing them at sites providing the highest possible output. These sites are often located far away from consumption centers, making compulsory the transmission of large amounts of energy from generation to demand. In the global scenario, the necessary capacity of the power infrastructure for doing such exceeds by far the existing infrastructure and therefore new transmission capacity is necessary. Taking into account that large amounts of Renewable Energy Sources (RES) are to be integrated in the current power system and that most of the generation will take place at remote locations requiring new transmission assets, this article answers the question of whether a supergrid is necessary to enable this transformation.

This article is categorized under:

Energy Infrastructure > Systems and Infrastructure

Energy Infrastructure > Climate and Environment
High efficiency photovoltaics: on the way to becoming a major electricity source
Authors: Wang Xiaoting , Byrne John , Kurdgelashvili Lado , Barnett Allen
Published: August 2012

The dramatic growth of the photovoltaic (PV) industry—accelerated by increased economies of scale, technology improvements, research and development efforts, and strong policy support—has pushed PV to set out on its pathway to becoming a major electricity source. The speed and course of this pathway will be determined by the development of PV energy price and its relation to market electricity sales price. The current gap between PV energy price and market electricity sales is often covered by substantial government subsidies. Using the United States PV market as a case study to illustrate the need for PV energy price decline, this article details the potential contribution of high‐efficiency PV based on different materials to realize such a decline and a substantial PV electricity share. It is found that—with considerable government support—PV's electricity share in the United States can rise to 25% by 2050. In order to help the PV industry achieve significant progress without large government subsidies, more radical decline of PV system cost is necessary. As such, quantitative analysis is deployed to investigate the value of module efficiency in lowering the total PV electricity cost through a levelized cost of energy analysis. Next, the article investigates in detail the research and development opportunities for high‐efficiency PV and projects the required efficiency‐price ranges for different types of PV modules.

This article is categorized under:

Photovoltaics > Economics and Policy
Large‐scale wind deployment, social acceptance
Authors: Horbaty Robert , Huber Stefanie , Ellis Geraint
Published: August 2012

The public is typically in agreement with the renewable energy targets established in many national states and generally supports the idea of increased reliance on wind energy. Nevertheless, many specific wind power projects face significant local opposition. A key question for the wind energy sector is, therefore, how to better engage local people to foster support for specific projects. IEA Wind Task 28 on Social Acceptance of Wind Energy Projects aims to facilitate wind energy development by reviewing current practices, emerging ideas, and exchanging successful practices among the participating countries. It also aims to disseminate the insights of leading research to a nontechnical audience, including project developers, local planning officials, and the general public. The interdisciplinary approach adopted by Task 28 enables an in‐depth understanding of the nature of opposition to wind projects and a critical assessment of emerging strategies for social acceptance. Task 28 has analyzed a range of key issues related to social acceptance of wind energy, including the impacts on landscapes and ecosystems, on standard of living and well‐being, the implementation of energy policy and spatial planning, the distribution of costs and benefits, and procedural justice. It is clear that although wind energy has many benefits; however, specific projects do impact local communities. As such the concerns of the affected people have to be taken seriously. Moreover, as opposition is rarely without foundation, it is in the interests of developers and advocates to engage local people and to improve projects for the benefit of all.

This article is categorized under:

Wind Power > Economics and Policy
Enhanced production of α-cyclodextrin glycosyltransferase in Escherichia coli by systematic codon usage optimization
Authors: Liu Hua , Li Jianghua , Du Guocheng , Zhou Jingwen , Chen Jian
Published: August 2012

Enhancing the production of α-cyclodextrin glycosyltransferase (α-CGTase) is a key aim in α-CGTase industries. Here, the mature α-cgt gene from Paenibacillus macerans JFB05-01 was redesigned with systematic codon optimization to preferentially match codon frequencies of Escherichia coli without altering the amino acid sequence. Following synthesis, codon-optimized α-cgt (coα-cgt) and wild-type α-cgt (wtα-cgt) genes were cloned into pET-20b(+) and expressed in E. coli BL21(DE3). The total protein yield of the synthetic gene was greater than wtα-cgt expression (1,710 mg L−1) by 2,520 mg L−1, with the extracellular enzyme activity being improved to 55.3 U mL−1 in flask fermentation. ΔG values at -3 to +50 of the pelB site of both genes were −19.10 kcal mol−1. Functionally, coα-CGTase was equally as effective as wtα-CGTase in forming α-cyclodextrin (α-CD). These findings suggest that preferred codon usage is advantageous for translational efficiency to increase protein expression. Finally, batch fermentation was applied, and the extracellular coα-CGTase enzyme activity was 326 % that of wtα-CGTase. The results suggest that codon optimization is a reasonable strategy to improve the yield of α-CGTase for industrial application.
Functional significance of the copper transporter ATP7 in peptidergic neurons and endocrine cells in Drosophila melanogaster
Authors: Sellami Azza , Wegener Christian , Veenstra Jan A.
Published: August 2012

The Drosophila ATP7 copper transporter has sequence homology to the human copper transporters ATP7A and ATP7B, which are defective in Menkes and Wilson disease, respectively. We show here that in Drosophila ATP7 is expressed by many peptidergic neurons. As C‐terminal amidation of neuropeptides depends on the copper‐containing enzyme PHM, it seemed likely that in the absence of ATP7 the activity of PHM might be compromised. Indeed, inhibition of ATP7 expression by RNAi led to a decrease in mature amidated neuropeptides and the appearance of C‐terminally Gly‐extended neuropeptides. The strength of this effect differed from one cell type to another; it was very pronounced for AKH and corazonin, but much less so for SIFamide and myosuppressin. Nevertheless, down‐regulation of ATP7 specifically in the SIFamide‐expressing neurons resulted in male–male courtship behavior.
Detection of cancer‐specific epigenomic changes in biofluids: Powerful tools in biomarker discovery and application
Authors: Nogueira da Costa André , Herceg Zdenko
Published: August 2012

The genetic and epigenetic material originating from tumour that can be found in body fluids of individuals with cancer harbours tumour‐specific alterations and represents an attractive target for biomarker discovery. Epigenetic changes (DNA methylation, histone modifications and non‐coding RNAs) are present ubiquitously in virtually all types of human malignancies and may appear in early cancer development, and thus they provide particularly attractive markers with broad applications in diagnostics. In addition, because changes in the epigenome may constitute a signature of specific exposure to certain risk factors, they have the potential to serve as highly specific biomarkers for risk assessment. While reliable detection of cancer‐specific epigenetic changes has proven to be technically challenging, a substantial progress has been made in developing the methodologies that allow an efficient and sensitive detection of epigenomic changes using the material originating from body fluids. In this review we discuss the application of epigenomics as a tool for biomarker research, with the focus on the analysis of DNA methylation in biofluids.
Numerical and functional responses of intestinal helminths in three rajid skates: evidence for competition between parasites?
Authors: RANDHAWA HASEEB S.
Published: August 2012

Host-parasite interactions generally involve communities of parasites. Within these communities, species will co-exist and/or interact with one another in a manner either benefiting the species involved or to the detriment of one or more of the species. At the level of helminth infracommunities, evidence for intra- and inter-specific competition includes numerical responses, i.e. those regulating helminth intensity of infection, and functional responses, i.e. where the presence of competitors modifies the realised niche of infrapopulations. The objectives of this study are to assess the numerical and functional responses of helminths in infracommunities from 3 rajid skates using general linear models. Despite a lack of numerical responses, functional responses to intra- and inter-specific interactions were observed. A positive correlation between the number of individuals in an infrapopulation and its niche breadth (functional response) was observed for the tapewormsPseudanthobothriumspp. andEcheneibothriumspp., in all their respective hosts, and for the nematodePseudanisakissp. in the little skate. Evidence for inter-specific competition includes niche shifts inPseudanthobothrium purtoni(exlittle skate) andPseudanisakissp. (exthorny skate) in the presence ofPseudanisakissp. and the tapewormGrillotiasp., respectively. These results are consistent with other studies in providing evidence for competition between helminths of skates.
Variation in fecal egg counts in horses managed for conservation purposes: individual egg shedding consistency, age effects and seasonal variation
Authors: WOOD E. L. D. , MATTHEWS J. B. , STEPHENSON S. , SLOTE M. , NUSSEY D. H.
Published: August 2012

Cyathostomins are the most prevalent equine intestinal parasites and resistance has been reported in these nematodes against all 3 licensed anthelmintic classes. Strategies need to be developed that are less dependent upon drugs and more reliant on management-based control. To develop these we need to understand natural transmission patterns better. Here, we analysed longitudinal fecal egg count (FEC) data from 5 pony populations used for conservation purposes. We tested how egg excretion varied amongst populations and individuals, and how this was affected by age and climate. There was evidence for consistency in FECs over time at the individual level; this was generally weak and accounted for <10% of the total variance. Animals <5 years old had higher FECs and there was profound seasonal variation in FECs, with highest levels recorded in spring/summer. Effects of monthly temperature and rainfall explained most, but not all, of the observed seasonal variation and associations between climate measures and FECs were stronger in younger versus adult animals. One population was occasionally treated with anthelmintics and analysis of this population suggested that treatment substantially altered the seasonal dynamics. This paper highlights the variability in strongyle egg excretion amongst individuals and the factors involved in this variation.
Neural response to the observable self in social anxiety disorder
Authors: Pujol J. , Giménez M. , Ortiz H. , Soriano-Mas C. , López-Solà M. , Farré M. , Deus J. , Merlo-Pich E. , Harrison B. J. , Cardoner N. , Navinés R. , Martín-Santos R.
Published: August 2012

Background

Distorted images of the observable self are considered crucial in the development and maintenance of social anxiety. We generated an experimental situation in which participants viewed themselves from an observer's perspective when exposed to scrutiny and evaluation by others.

Method

Twenty patients with social anxiety disorder (SAD) and 20 control subjects were assessed using functional magnetic resonance imaging (fMRI) during the public exposure of pre-recorded videos in which they were each shown performing a verbal task. The examiners acted as the audience in the experiment and rated performance. Whole-brain functional maps were computed using Statistical Parametric Mapping.

Results

Robust activation was observed in regions related to self-face recognition, emotional response and general arousal in both study groups. Patients showed significantly greater activation only in the primary visual cortex. By contrast, they showed significant deactivation or smaller activation in dorsal frontoparietal and anterior cingulate cortices relevant to the cognitive control of negative emotion. Task-related anxiety ratings revealed a pattern of negative correlation with activation in this frontoparietal/cingulate network. Importantly, the relationship between social anxiety scores and neural response showed an inverted-U function with positive correlations in the lower score range and negative correlations in the higher range.

Conclusions

Our findings suggest that exposure to scrutiny and evaluation in SAD may be associated with changes in cortical systems mediating the cognitive components of anxiety. Disorder severity seems to be relevant in shaping the neural response pattern, which is distinctively characterized by a reduced cortical response in the most severe cases.
Welfare Mom as Warrior Mom: Discourse in the 2003 Single Mothers' Protest in Israel
Authors: HERBST ANAT
Published: August 2012

This study applies critical discourse analysis to the public discourse in Israel regarding the battle of single mothers against extensive welfare cuts. Using the protest of July 2003 as a case study, the article points to parallels between Israel's neo-liberal welfare discourse and that in the US, but also reveals a competing discourse in Israel that incorporated several basic cultural motifs: motherhood, militarism, Zionism and nationalism. While the latter discourse stresses the importance of motherhood and its contribution to society, the former presents single mothers as dependents living off the country's welfare resources. The discourse analysis shows that despite the seeming legitimacy of motherhood in Israel, especially of the Zionist mother who gives birth to soldiers, the negative imagery applied by the neo-liberal ideology to single mothers who receive allowances succeeded in eroding this legitimacy.
Multi-waypoint visual homing in piecewise linear trajectory
Authors: Fu Yu , Hsiang Tien-Ruey , Chung Sheng-Luen
Published: August 2012

This paper proposes an image sequence-based navigation method under the teaching-replay framework for robots in piecewise linear routes. Waypoints used by the robot contain either the positions with large heading changes or selected midway positions between junctions. The robot applies local visual homing to move between consecutive waypoints. The arrival at a waypoint is determined by minimizing the average vertical displacements of feature correspondences. The performance of the proposed approach is supported by extensive experiments in hallway and office environments. While the homing speed of robots using other approaches is constrained by the speed in the teaching phase, our robot is not bounded by such limit and can travel much faster without compromising the homing accuracy.
Indirect force control development procedure
Authors: Winiarski Tomasz , Woźniak Adam
Published: August 2012

Addition of extra sensors, especially video cameras and force sensors, under control of appropriate software makes robotic manipulators working in factories suitable for a range of new applications. This paper presents a method of manipulator indirect force control development, in which the force set values are specified in the operational space and the manipulator is equipped with a force sensor in its wrist. Standard control development methods need the estimation of parameters of the detailed model of a manipulator and position servos, which is a complicated and time-consuming task. Hence, in this work a time-efficient hybrid procedure of controller development is proposed consisting of both analytical and experimental stages: proposal of an approximate continuous model of a manipulator, experimental determination and verification of its parameter values using the resonance phenomenon, continuous regulator development, and digitization of the regulator.
Generalized maximum principles and the rigidity of complete spacelike hypersurfaces
Authors: CAMARGO FERNANDA , CAMINHA ANTONIO , DE LIMA HENRIQUE , PARENTE ULISSES
Published: August 2012

In this paper, we apply several forms of generalized maximum principles to the study of the uniqueness of complete, non-compact spacelike hypersurfaces immersed in a class of Lorentzian warped products obeying a suitable convergence condition.
Comparative assessment of different methods for using land-cover variables for distribution modelling ofSalamandra salamandra longirotris
Authors: ROMERO DAVID , OLIVERO JESÚS , REAL RAIMUNDO
Published: August 2012

Predictive models are frequently used to define the most suitable areas for species protection or reintroduction. Land-cover variables can be used in different ways for distribution modelling. The surface area of a set of land-cover classes is often used, each land-cover presence/absence or the distance to them from any point of the study area can be preferred; multiple types of land-cover variables may be combined to produce a single model. This paper assesses whether different approaches to using land-cover variables may lead to different ecological conclusions when interpreted for conservation by focusing on the distribution of the salamaderSalamandra salamandra longirostris, an endangered amphibian subspecies in the south of the Iberian Peninsula. Twenty-eight land-cover classes and another 42 environmental variables were used to construct four different models. Three models used a unique type of land-cover variable: either the presence of each class, the surface area of each class or the distance to each class, with all three variable types jointly entered in a fourth model. All models attained acceptable scores according to some criteria (discrimination, descriptive and predictive capacities, classification accuracy and parsimony); however most of the assessment parameters computed indicated a better performance of the models using either the surface area of land classes or the distance to them from every sampled square, compared to the model using class presences. The best scores were obtained with the fourth model, which combined different types of land-cover variables. This model suggested that oak forest fragmentation in favour of herbaceous crops and pastures may have negative effects on the distribution ofS. s. longirostris. This was only partially suggested by the first three models, which considered a single type of land-cover variable, demonstrating the importance of considering a multi-variable analysis for conservation planning.
Lifestyle values, resilience, and nature-based tourism's contribution to conservation on Australia's Great Barrier Reef
Authors: BIGGS D. , BAN N. C. , HALL C. M.
Published: August 2012

Innovative partnerships for conservation are required to stem the tide of continued ecosystem degradation. Nature-based tourism is one such partnership. Yet the natural attractions that nature-based tourism depends on are under increasing anthropogenic threat. Because of their dependence on international visitors, nature-based tourism enterprises are under additional pressure from socioeconomic and political crises in a globalized world. Recent research shows that lifestyle values, the motives that entice owners and staff of tourism enterprises to live and work in a chosen natural attraction, strengthen the resilience of enterprises to crises. This paper empirically explores the relationship between the lifestyle values of nature-based tourism enterprises, their resilience, and their support of and contribution to conservation of Australia's Great Barrier Reef. Semi-structured interviews with the owners and senior managers of 48 reef tourism enterprises showed that those that reported high lifestyle values had higher levels of conservation ethic and participated more extensively in conservation actions. The relationship between resilience and conservation ethic was not statistically significant. Bureaucratic, regulatory and cost constraints, and a lack of knowledge, limit enterprise participation in conservation. Conservation agencies can work to reduce some of these constraints to ensure that conservation benefits from nature-based tourism enterprises are maximized.
A continuum theory for one-dimensional self-similar elasticity and applications to wave propagation and diffusion
Authors: MICHELITSCH THOMAS M. , MAUGIN GÉRARD A. , RAHMAN MUJIBUR , DEROGAR SHAHRAM , NOWAKOWSKI ANDRZEJ F. , NICOLLEAU FRANCK C. G. A.
Published: August 2012

We analyse some fundamental problems of linear elasticity in one-dimensional (1D) continua where the material points of the medium interact in a self-similar manner. This continuum with ‘self-similar’ elastic properties is obtained as the continuum limit of a linear chain with self-similar harmonic interactions (harmonic springs) which was introduced in [19] and (Michelitsch T.M. (2011) The self-similar field and its application to a diffusion problem. J. Phys. A Math. Theor.44, 465206). We deduce a continuous field approach where the self-similar elasticity is reflected by self-similar Laplacian-generating equations of motion which are spatially non-local convolutions with power-function kernels (fractional integrals). We obtain closed-form expressions for the static displacement Green's function due to a unit δ-force. In the dynamic framework we derive the solution of the Cauchy problem and the retarded Green's function. We deduce the distributions of a self-similar variant of diffusion problem with Lévi-stable distributions as solutions with infinite mean fluctuations. In both dynamic cases we obtain a hierarchy of solutions for the self-similar Poisson's equation, which we call ‘self-similar potentials’. These non-local singular potentials are in a sense self-similar analogues to Newtonian potentials and to the 1D Dirac's δ-function. The approach can be a point of departure for a theory of self-similar elasticity in 2D and 3D and for other field theories (e.g. in electrodynamics) of systems with scale invariant interactions.
Cops and Robbers on Geometric Graphs
Authors: BEVERIDGE ANDREW , DUDEK ANDRZEJ , FRIEZE ALAN , MÜLLER TOBIAS
Published: August 2012

Cops and robbers is a turn-based pursuit game played on a graph G. One robber is pursued by a set of cops. In each round, these agents move between vertices along the edges of the graph. The cop number c(G) denotes the minimum number of cops required to catch the robber in finite time. We study the cop number of geometric graphs. For points x1, . . ., xn ∈ ℝ2, and r ∈ ℝ+, the vertex set of the geometric graph G(x1, . . ., xn; r) is the graph on these n points, with xi, xj adjacent when ∥xi − xj∥ ≤ r. We prove that c(G) ≤ 9 for any connected geometric graph G in ℝ2 and we give an example of a connected geometric graph with c(G) = 3. We improve on our upper bound for random geometric graphs that are sufficiently dense. Let (n,r) denote the probability space of geometric graphs with n vertices chosen uniformly and independently from [0,1]2. For G ∈ (n,r), we show that with high probability (w.h.p.), if r ≥ K1 (log n/n)1/4 then c(G) ≤ 2, and if r ≥ K2(log n/n)1/5 then c(G) = 1, where K1, K2 > 0 are absolute constants. Finally, we provide a lower bound near the connectivity regime of (n,r): if r ≤ K3 log n/ then c(G) > 1 w.h.p., where K3 > 0 is an absolute constant.
HARM AND ITS MORAL SIGNIFICANCE
Authors: Shiffrin Seana Valentine
Published: August 2012

Standard, familiar models portray harms and benefits as symmetrical. Usually, harm is portrayed as involving a worsening of one's situation, and benefits as involving an improvement. Yet morally, the aversion, prevention, and relief of harms seem, at least presumptively, to matter more than the provision, protection, and maintenance of comparable and often greater benefits. Standard models of harms and benefits have difficulty acknowledging this priority, much less explaining it. They also fail to identify harm accurately and reliably. In this paper, I develop these problems, argue that we should reconsider our commitment to the standard models, and then merely gesture at the direction in which we might locate a superior approach, one that better accounts for the moral significance of harm and its relation to autonomy rights.
The Feasibility and Acceptability of a Cognitive-Behavioural Self-help Intervention for Adolescents with Obsessive-Compulsive Disorder
Authors: Robinson Sarah , Turner Cynthia , Heyman Isobel , Farquharson Lorna
Published: August 2012

Background:Breaking Free from OCD is a cognitive behavioural self-help book for young people with obsessive compulsive disorder (OCD). The book is written for 11–16 year olds as a first step intervention for reducing mild to moderate symptoms of OCD. Aims: This report describes a preliminary evaluation of the feasibility and acceptability of the book as a self-help intervention. Method: Using a case-series design, eight 11–16 year olds with OCD were monitored for symptom stability 3 weeks prior to receiving Breaking Free from OCD for use over an 8-week period. Weekly telephone calls were received to complete the CY-BOCS for symptom severity and to monitor adherence to the intervention. The CHOCI and SDQ were sent to participants and their parents pre-, mid- and post-intervention. Results: There was a significant reduction in CY-BOCS symptom severity over the course of the intervention; however, there were no statistically significant changes on the self-report measures. The intervention was well received by the majority of young people who took part. Conclusions:Breaking Free from OCD may help young people with OCD and is an acceptable low intensity intervention. This evaluation is the first step in developing low intensity approaches for child OCD.
Entity-wide risk management for pension funds ‐ Abstract of the Edinburgh discussion
Authors: Kemp Malcolm
Published: August 2012

This abstract relates to the following paper:

KempM.H.D., and PatelC.C.Entity-wide risk management for pension funds. British Actuarial Journal, doi:10.1017/S1357321712000086
Entity-wide risk management for pension funds ‐ Abstract of the London discussion
Authors: Kemp Malcolm
Published: August 2012

This abstract relates to the following paper:

KempM.H.D., and PatelC.C.Entity-wide risk management for pension funds. British Actuarial Journal, doi:10.1017/S1357321712000086
Whole grain consumption is inversely associated with BMI Z-score in rural school-aged children
Authors: Choumenkovitch Silvina F , McKeown Nicola M , Tovar Alison , Hyatt Raymond R , Kraak Vivica I , Hastings Alia V , Herzog Julia Bloom , Economos Christina D
Published: August 2012

Objective

To examine the relationship between intake of whole grains and BMI Z-score in rural children.

Design

General linear models and logistic regression were used to examine the cross-sectional associations between whole grain intake and BMI Z-score, prevalence and odds ratios of overweight and obesity. Dietary intake was assessed using the Block Food Screener for ages 2–17 years. Children were classified into three categories according to servings of whole grain intake: <1·0 serving/d, 1·0–1·5 servings/d and >1·5 servings/d.

Setting

The CHANGE (Creating Healthy, Active and Nurturing Growing-up Environments) study, an obesity prevention intervention in elementary schools in eight rural US communities in California, Mississippi, Kentucky and South Carolina.

Subjects

Seven hundred and ninety-two children attending 3rd–6th grade.

Results

After adjusting for age, sex, race/ethnicity, physical activity and state of residence, whole grain intake was inversely associated with BMI Z-score (0·90 v. 0·61 in the lowest v. the highest whole grain intake category; P trend = 0·01). Children who consumed >1·5 servings of whole grains/d had a 40 % lower risk of being obese (OR = 0·60; 95 % CI 0·38, 0·95, P = 0·02) compared with children who consumed <1·0 serving/d. Further adjustment for potential dietary predictors of body weight (fruit, vegetable and dairy intakes) did not change the observed associations.

Conclusions

Increasing the intake of whole grains as part of an overall healthy lifestyle may be beneficial for children to achieve and maintain a healthy weight.
Dietary salt intake assessed by 24 h urinary sodium excretion in Australian schoolchildren aged 5–13 years
Authors: Grimes Carley A , Riddell Lynn J , Campbell Karen J , Nowson Caryl A
Published: August 2012

Objective

To measure total daily salt intake using 24 h urinary Na excretion within a sample of Victorian schoolchildren aged 5–13 years and to assess discretionary salt use habits of children and parents.

Design

Cross-sectional study.

Setting

Completed within a convenience sample of independent primary schools (n9) located in Victoria, Australia.

Subjects

Two hundred and sixty children completed a 24 h urine collection over a school (34 %) or non-school day (66 %). Samples deemed incomplete (n18), an over-collection (n1) or that were incorrectly processed at the laboratory (n3) were excluded.

Results

The sample comprised 120 boys and 118 girls with a mean age of 9·8 (sd1·7) years. The average 24 h urinary Na excretion (n238) was 103 (sd43) mmol/24 h (salt equivalent 6·0 (sd2·5) g/d). Daily Na excretion did not differ by sex; boys 105 (sd46) mmol/24 h (salt equivalent 6·1 (sd2·7) g/d) and girls 100 (sd41) mmol/24 h (salt equivalent 5·9 (sd2·4) g/d;P= 0·38). Sixty-nine per cent of children (n164) exceeded the recommended daily Upper Limit for Na. Reported discretionary salt use was common: two-thirds of parents reported adding salt during cooking and almost half of children reported adding salt at the table.

Conclusions

The majority of children had salt intakes exceeding the recommended daily Upper Limit. Strategies to lower salt intake in children are urgently required, and should include product reformulation of lower-sodium food products combined with interventions targeting discretionary salt use within the home.
Relative validation of a quantitative FFQ for use in Brazilian pregnant women
Authors: Barbieri Patrícia , Nishimura Renata Y , Crivellenti Lívia C , Sartorelli Daniela S
Published: August 2012

Objective

To evaluate the ability of an FFQ, designed for use in Brazilian pregnant women, to estimate nutrient intakes during pregnancy.

Design

A prospective study was conducted among 103 pregnant women attended by the Brazilian national health-care service. Food intake during pregnancy was evaluated by three 24 h dietary recalls (24hR), one per trimester of pregnancy, and also by two FFQ. The FFQ with eighty-five food items included questions about frequency of intake and portion sizes during two periods: the first 24 weeks of pregnancy and the pregnancy period as a whole. Deattenuated Pearson's correlation coefficients and joint classification into quartiles of nutrient intake were applied.

Setting

Ribeirão Preto, São Paulo State, Brazil.

Subjects

One hundred and three pregnant women, aged 18–35 years.

Results

Acceptable correlation coefficients (r > 0·35) were found for Ca, K, Zn, Mg, fibre, vitamin C, niacin and folic acid for intake for the first 24 weeks; and for energy, lipids, protein, carbohydrate, Fe, K, Zn, fibre, vitamin B6, riboflavin and niacin for the gestational period as a whole. A high proportion of study participants (≥70 %) were categorized into the same or adjacent quartiles for estimated energy, carbohydrate, Ca, K, fibre, Zn, cholesterol, vitamin A, riboflavin, niacin, vitamin C, vitamin E and folic acid. Gross misclassification ranged from 2·3 % (dietary fibre) to 12·5 % (vitamin A, thiamin and SFA).

Conclusions

The FFQ is a useful tool for assessing categories of nutrient intake during pregnancy, since a high proportion of women were classified into the same or adjacent quartiles.
Testing the fetal overnutrition hypothesis; the relationship of maternal and paternal adiposity to adiposity, insulin resistance and cardiovascular risk factors in Indian children
Authors: Veena Sargoor R , Krishnaveni Ghattu V , Karat Samuel C , Osmond Clive , Fall Caroline HD
Published: August 2012

Objective

We aimed to test the fetal overnutrition hypothesis by comparing the associations of maternal and paternal adiposity (sum of skinfolds) with adiposity and cardiovascular risk factors in children.

Design

Children from a prospective birth cohort had anthropometry, fat percentage (bio-impedance), plasma glucose, insulin and lipid concentrations and blood pressure measured at 9·5 years of age. Detailed anthropometric measurements were recorded for mothers (at 30 ± 2 weeks’ gestation) and fathers (5 years following the index pregnancy).

Setting

Holdsworth Memorial Hospital, Mysore, India.

Subjects

Children (n504), born to mothers with normal glucose tolerance during pregnancy.

Results

Twenty-eight per cent of mothers and 38 % of fathers were overweight/obese (BMI ≥ 25·0 kg/m2), but only 4 % of the children were overweight/obese (WHO age- and sex-specific BMI ≥ 18·2 kg/m2). The children's adiposity (BMI, sum of skinfolds, fat percentage and waist circumference), fasting insulin concentration and insulin resistance increased with increasing maternal and paternal sum of skinfolds adjusted for the child's sex, age and socio-economic status. Maternal and paternal effects were similar. The associations with fasting insulin and insulin resistance were attenuated after adjusting for the child's current adiposity.

Conclusions

In this population, both maternal and paternal adiposity equally predict adiposity and insulin resistance in the children. This suggests that shared family environment and lifestyle, or genetic/epigenetic factors, influence child adiposity. Our findings do not support the hypothesis that there is an intra-uterine overnutrition effect of maternal adiposity in non-diabetic pregnancies, although we cannot rule out such an effect in cases of extreme maternal obesity, which is rare in our population.
Mini-Review: Probing the limits of extremophilic life in extraterrestrial environment-simulated experiments
Authors: Lage Claudia A.S. , Dalmaso Gabriel Z.L. , Teixeira Lia C.R.S. , Bendia Amanda G. , Paulino-Lima Ivan G. , Galante Douglas , Janot-Pacheco Eduardo , Abrevaya Ximena C. , Azúa-Bustos Armando , Pelizzari Vivian H. , Rosado Alexandre S.
Published: August 2012

Astrobiology is a relatively recent scientific field that seeks to understand the origin and dynamics of life in the Universe. Several hypotheses have been proposed to explain life in the cosmic context throughout human history, but only now, technology has allowed many of them to be tested. Laboratory experiments have been able to show how chemical elements essential to life, such as carbon, nitrogen, oxygen and hydrogen combine in biologically important compounds. Interestingly, these compounds are ubiquitous. How these compounds were combined to the point of originating cells and complex organisms is still to be unveiled by science. However, our 4.5 billion years old Solar system appeared in a 10 billion years old Universe. Thus, simple cells such as micro-organisms may have had time to form in planets older than ours or in other suitable places in the Universe. One hypothesis related to the appearance of life on Earth is called panspermia, which predicts that microbial life could have been formed in the Universe billions of years ago, travelling between planets, and inseminating units of life that could have become more complex in habitable planets such as Earth. A project designed to test the viability of extremophile micro-organisms exposed to simulated extraterrestrial environments is in progress at the Carlos Chagas Filho Institute of Biophysics (UFRJ, Brazil) to test whether microbial life could withstand inhospitable environments. Radiation-resistant (known or novel ones) micro-organisms collected from extreme terrestrial environments have been exposed (at synchrotron accelerators) to intense radiation sources simulating Solar radiation, capable of emitting radiation in a few hours equivalent to many years of accumulated doses. The results obtained in these experiments reveal an interesting possibility of the existence of microbial life beyond Earth.
Privatization, Marketization, and Neoliberalism—The Political Dynamics of Post-Katrina New Orleans
Authors: Sakakeeny Matt
Published: August 2012

Hurricane Katrina was a “disaster” both “natural” and “social.” The storm destroyed a major American city that, like most American cities, was already the site of great inequality and vulnerability. It also dramatically put to the test both the logistical capabilities and the political responsibilities of national, state, and local governmental institutions.The Neoliberal Deluge: Hurricane Katrina, Late Capitalism, and the Remaking of New Orleansis an important collection of essays on the dynamics of “remaking New Orleans” and the limits of that effort. We have thus asked a diverse group of political scientists to review the book, and at the same time to treat it as an opportunity to reflect on two related questions: 1) What are the most important economic, cultural, and political dimensions of the crisis precipitated by Katrina, both for New Orleans and for US cities more generally? 2) What resources does political science as a discipline possess to help us understand these issues, and can political science as a discipline do a better job on this score?—Jeffrey C. Issac, Editor
Reputation and Power: Organizational Image and Pharmaceutical Regulation at the FDA. By Daniel Carpenter. Princeton: Princeton University Press, 2010. 856p. $78.50 cloth, $35.00 paper.
Authors: Ferejohn John
Published: August 2012

Dan Carpenter's massive new study of the Food and Drug Administration (FDA) is a definitive study of regulatory politics and administrative behavior destined to stand alongside other classic studies of administrative agencies, such as Herbert Kaufman's The Forest Ranger (1960) or Martha Derthick's Policy Making for Social Security (1979). Like Carpenter's earlier work, Reputation and Power is marked by deep erudition, thorough scholarship, painstaking attention to detail, and a wide-ranging attention to alternative disciplinary paradigms. And it is argued with great craft, subtlety, and creativity both in developing its historical narrative and in its cogent theoretical analysis.