bluuebunny/crossref_metadata_2025 huggingface dataset:
Psychiatrist availability, social disintegration, and suicide deaths in U.S. counties, 1990–1995
Authors: Kposowa Augustine J.
Published: December 2008

Previous studies have found that primary care resources are associated with various health outcomes. The primary purpose of the study was to test for associations between psychiatrist availability, social disintegration and suicide rates. Data utilized were from the 2002 Area Resource File on U.S. counties (N=3080). Suicide rates were averaged over 6 years covering 1990 through 1995. Poisson and Negative binomial regression models were used to assess the association of psychiatrist availability and suicide rate ratios. Availability of psychiatrists was significantly related to suicide. Counties with greater availability of psychiatrists per 10,000 experienced a 0.12% reduction in their suicide rates (β=−0.0012, incidence density ratio [IDR]=0.9988, 95% CI=0.9984–0.9992). Divorce strongly elevated suicide rates (β=0.0724, IDR=1.0751, 95% CI=1.0664–.0858). Counties with a high percentage of men 65 years or older had significantly high suicide rates. An increase in the White population between 1980 and 1990 was also associated with a significant increase in suicide. Increases in psychiatrists reduced suicide rates, but the association was small. Psychiatrist availability may also partially reduce the effects of social disintegration at the county level. Primary care was not associated with suicide once other variables, including hospital beds were taken into account. Results provide evidence to suggest that greater mental health promotion might reduce area inequalities in suicide rates. © 2008 Wiley Periodicals, Inc.
Neighborhood immigrant concentration, acculturation, and cultural alienation in former soviet immigrant women
Authors: Miller Arlene Michaels , Birman Dina , Zenk Shannon , Wang Edward , Sorokin Olga , Connor Jorgia
Published: December 2008

Several acculturation theories note the importance of surrounding context, but few studies describe neighborhood influences on immigrant adaptation. The purpose of this study was to examine relationships among neighborhood immigrant concentration, acculturation, and alienation for 151 women aged 44–80 from the former Soviet Union who lived in the US fewer than 13 years. Participants resided in 65 census tracts in the Chicago area with varying concentrations of Russian‐speaking and diverse immigrants. Results from self‐report questionnaires suggest that the effect of acculturation on alienation varies depending on neighborhood characteristics. The study also demonstrates the complexity of individual and contextual influences on immigrant adoption. Understanding these relationships is important for developing community‐based and neighborhood‐level interventions to enhance the mental health of immigrants. © 2008 Wiley Periodicals, Inc.
Modified PEG‐anilinoquinazoline derivatives as potential EGFR PET agents
Authors: Dissoki Samar , Eshet Renana , Billauer Hana , Mishani Eyal
Published: December 2008

Inhibition of epidermal growth factor receptor tyrosine kinase (EGFR‐TK) has emerged as a major approach for cancer‐targeted therapy. Consequently, there has been a great interest in the use of labeled EGFR‐TK inhibitors as positron emission tomography (PET) imaging agents. Currently, the developed agents did not yield adequate PET imaging of animal models probably due to poor solubility, rapid washout from blood, and low stability in vivo. In order to overcome these hurdles, new derivatives of previously reported inhibitors (ML04, 2) with decreased log P and increased solubility were designed and synthesized. These compounds (3–5) exhibited high autophosphorylation inhibitory potency with an IC50 of 5–35 nM, decreased log P's (3.1, 3.34, and 3.45, respectively), and significantly increased solubility (630, 300, and 120 µg/mL, respectively) relative to the previously reported parent compound 2 (log P=3.7, solubility=3.5 µg/mL). The labeling of compound 5 with [18F] and compounds 3 and 4 with [11C] and [124I], respectively, involved a one‐step radiosynthesis. Compounds 3–5 were obtained with a total decay‐corrected radiochemical yields of 13, 31, and 5%, respectively, and were found to be stable in blood. The positive outcome achieved with compounds 3–5 merits further in vivo evaluation as PET bioprobes. Copyright © 2008 John Wiley & Sons, Ltd.
Issues surrounding lymphadenectomy in the management of endometrial cancer
Authors: Bernardini Marcus Q. , Murphy Joan K.
Published: December 2008

The development of surgical staging in the management of endometrial cancer has arisen over the last several decades with anticipated benefits including prognostic information, tailoring of adjuvant treatment, and a possible therapeutic effect. This review addresses the important issues surrounding lymphadenectomy in endometrial cancer. Other issues including the use of sentinel lymph node techniques, advanced imaging modalities and the consideration of a binary grading system to simplify triaging of patients will also be discussed. J. Surg. Oncol. 2009;99:232–241. © 2008 Wiley‐Liss, Inc.
Hip transposition as a universal surgical procedure for periacetabular tumors of the pelvis
Authors: Gebert Carsten , Gosheger Georg , Winkelmann Winfried
Published: December 2008

Surgical treatment of pelvic tumors represents one of the most challenging problems in musculoskeletal oncology, especially in the periacetabular region. Because of the complex anatomy and demanding biomechanical situation, surgery leads to a considerable disability while all possible types of reconstruction are often associated with high complication rates. Nevertheless, it is known that wide resection of the tumor is one of the key points for long‐term survival in sarcoma therapy. Therefore, hip transposition was established in our clinic as a universal tool for periacetabular tumors excelling in small foreign parts and resulting in acceptable complication rates with good functional outcome. The following article gives an overview of the technique and the indications of different types of hip transposition, which were developed from the first procedure, described and published by Winkelmann in 1988. J. Surg. Oncol. 2009;99: 169–172. © 2008 Wiley‐Liss, Inc.
On the same page: The value of paid and volunteer leaders sharing mental models in churches
Authors: Solansky Stephanie T. , Duchon Dennis , Plowman Donde Ashmos , Martínez Patricia G.
Published: December 2008

We examine the idea that mental models shared among paid and volunteer leaders are associated with improved financial performance in nonprofit organizations. Our empirical analysis of thirty‐seven churches yields evidence that organizations are more effective if paid and volunteer leaders have a shared task mental model—that is, if they report similar conceptualizations of organizational goals and decision‐making processes. These findings suggest that the extent of leaders' agreement on organizational goals and the processes of how decisions are made matter for organizational performance. We argue that it is as important to ensure that everyone is on the same page with regard to goals and how decisions are made as it is to have the “right” goals or right decision processes in place. Implications for practice and future research on shared mental models are discussed.
Getting to yes … or no: Nonprofit decision making and interorganizational restructuring
Authors: Campbell David A.
Published: December 2008

This article explores the decision‐making process nonprofit organizations use to determine whether to pursue merger or other forms of interorganizational restructuring. The research uses a case study design, analyzing four examples of interorganizational restructuring. The findings describe both the structure and the characteristics of the processes used in four cases. The research found that the decision‐making processes used in the four cases had several core elements. Participants in restructuring customized decision‐making processes to meet their needs, and power dynamics shaped those processes. Findings about the characteristics of the process emphasize the importance of communication and trust. How partners used power affected the decision‐making process and had implications for postmerger success. Decision‐making processes for cases involving two partners exhibited characteristics that were different from those involving multiple partners. Future research should consider the role of trust in restructuring decisions and the responsibilities of board and staff in the restructuring assessment process.
Where you stand depends on where you sit: Participation and reactions to change
Authors: Basinger Nancy Winemiller , Peterson Jessica Romine
Published: December 2008

Although a considerable body of research on strategic planning, organizational decision making, and organizational change has emphasized the importance of participation by key stakeholders for the successful management of organizational change, few empirical studies have produced in‐depth understanding of the differing perspectives of stakeholder groups according to their level of involvement in decisions about major change. This case study examines the differing perspectives and perceptions of stakeholders leading into and during the merger of two nonprofit arts organizations. It refines and enriches existing empirical research on the effects of participation on the implementation of change.
On comparison of the solutions for an axisymmetric flow
Authors: Hayat T. , Ahmad I. , Javed T.
Published: December 2008

Recently, Ariel (Comput Math Appl, 54 (2007), 1169–1183) explored the axially stretching flow of a viscous fluid in the presence of a velocity slip. He computed the solutions by noniterative technique, the homotopy perturbation method (HPM), and the perturbation and asymptotic methods (for small and large values of the slip parameter, respectively). Through comparison between these solutions, he claimed that HPM solution is the best solution showing close agreement with an exact solution. Here, we recomputed the flow problem considered in Ariel's work for the series solution by homotopy analysis method (HAM). It is found that HAM solution is identical with the presented exact solution in Ariel's work. Furthermore, the HAM solution is better than the HPM solution. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2009
Maximum norm error bounds of ADI and compact ADI methods for solving parabolic equations
Authors: Liao Hong‐Lin , Sun Zhi‐Zhong
Published: December 2008

Alternating direction implicit (ADI) schemes are computationally efficient and widely utilized for numerical approximation of the multidimensional parabolic equations. By using the discrete energy method, it is shown that the ADI solution is unconditionally convergent with the convergence order of two in the maximum norm. Considering an asymptotic expansion of the difference solution, we obtain a fourth‐order, in both time and space, approximation by one Richardson extrapolation. Extension of our technique to the higher‐order compact ADI schemes also yields the maximum norm error estimate of the discrete solution. And by one extrapolation, we obtain a sixth order accurate approximation when the time step is proportional to the squares of the spatial size. An numerical example is presented to support our theoretical results. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2010
Modeling of complex parison formation in extrusion blow molding: Effect of medium to large die heads and fuel tank geometry
Authors: Yousefi Azizeh‐Mitra , Atsbha Haile
Published: December 2008

This work presents the effect of die geometry and die gap opening on the extrudate swell phenomenon, in complex parison formation using the vertical wall distribution system (VWDS) and partial wall distribution system (PWDS). The BlowParison© software from IMI is used to predict the parison formation for a combined VWDS/PWDS system, accounting for swell, sag, and nonisothermal effects. This software couples a fluid mechanics approach to represent the die flow, with a solid mechanics approach to represent the parison behavior outside the die, and a mathematical swell model to account for the pronounced elongational and shear stresses at high Weissenberg numbers. The emphasis is placed on experimental validation of the predicted parison dimensions using four diverging die geometries and different sets of VWDS/PWDS profiles. The experimental and predicted weight profiles for a dissected fuel tank are also presented. Both experimental and simulation results suggest a strong dependence of extrudate swell to the die geometry in the die land zone. The results also demonstrate the validity of the numerical predictions for part design purposes given the multitude of experimental validations presented in this work. POLYM. ENG. SCI., 2009. Published by the Society of Plastics Engineers
Pea starch‐based composite films with pea hull fibers and pea hull fiber‐derived nanowhiskers
Authors: Chen Yun , Liu Changhua , Chang Peter R. , Anderson Debbie P. , Huneault Michel A.
Published: December 2008

New applications of both pea hull fiber (PHF) and PHF‐derived nanowhiskers (PHFNW), isolated from PHF by acid‐hydrolysis, as fillers in starch‐based biocomposite films were explored in this work. Two series of films were prepared by blending pea starch (PS), respectively, with PHF and PHFNW. The effects of PHF and PHFNW as filler on the structure and properties of the composite films were comparatively investigated by observation of morphology and analysis of thermal, optical, and mechanical properties. The results revealed that the PS/PHFNW nanocomposite films exhibited improved physical properties over both the neat PS film and PS/PHF microcomposite films. The light transmittance at 800 nm, tensile strength, elongation at break, and Young's modulus were 56.0%, 4.1 MPa (Megapascal), 30.1%, 40.3 MPa, respectively, for the PS film without filler; 58.0%, 7.6 MPa, 41.8%, and 415.2 MPa for the PS/PHFNW film containing 10 wt% filler; and 37.2%, 2.8 MPa, 17.0%, and 29.8 MPa for the PS/PHF film containing 10 wt% filler. The improvement to the properties of PS/PHFNW nanocomposite films may be attributed to the nanometer size effect of PHFNW, which resulted in the homogeneous dispersion of PHFNW within the PS, and the strong interactions between the matrix and the nanoscale filler. POLYM. ENG. SCI., 2009. Published by the Society of Plastics Engineers
Cavitation bubble dynamics in non‐Newtonian fluids
Authors: Brujan Emil‐Alexandru
Published: December 2008

Cavitation phenomena play important roles in many areas of science and engineering. The most interesting effect of the non‐Newtonian properties of the liquid is the reduction of cavitation damage and noise. This article reviews experimental and theoretical efforts to understand such phenomena. Two major areas of research are described, namely the dynamics of cavitation bubbles oscillating in a liquid of infinite extent, and the behavior of bubbles collapsing near rigid walls. POLYM. ENG. SCI., 2009. © 2008 Society of Plastics Engineers
Examining developmental differences in the social‐emotional problems among frequent bullies, victims, and bully/victims
Authors: O'Brennan Lindsey M. , Bradshaw Catherine P. , Sawyer Anne L.
Published: December 2008

Bullying poses a threat to children's social‐emotional functioning and their perceptions of school climate, yet few studies have examined different types of social‐emotional and behavior problems presented by children involved in bullying, as a bully, victim, or bully/victim across multiple school levels. The current study used data from 24,345 elementary‐, middle‐, and high‐school students to examine the association between frequent involvement in bullying and aggressive impulsivity, attitudes toward aggressive retaliation, internalizing symptoms, peer relations, and perceptions of school climate. Logistic regression analyses indicated that bully/victims were most likely to display internalizing symptoms, problems in peer relationships, and have poorer perceptions of the school environment. Both frequent bullies and bully/victims displayed aggressive‐impulsive behavior and endorsed retaliatory attitudes. High‐school students frequently involved in bullying tended to display the greatest risk for internalizing problems, but less risk for aggressive impulsivity. Developmental trends and implications for prevention and early intervention are discussed. © 2008 Wiley Periodicals, Inc.
MAP dendrimer elicits antibodies for detecting rat and mouse GH‐binding proteins
Authors: Aguilar Roberto M. , Talamantes Frank J. , Bustamante Juan J. , Muñoz Jesus , Treviño Lisa R. , Martinez Andrew O. , Haro Luis S.
Published: December 2008

The membrane‐bound rat GH‐R and an alternatively spliced isoform, the soluble rat GH‐BP, are comprised of identical N‐terminal GH‐binding domains; however, their C‐terminal sequences differ. Immunological reagents are needed to distinguish between the two isoforms in order to understand their respective roles in mediating the actions of GH. Accordingly, a tetravalent MAP dendrimer with four identical branches of a C‐terminal peptide sequence of the rat GH‐BP (GH‐BP263–279) was synthesized and used as an immunogen in rabbits. Solid‐phase peptide synthesis of four GH‐BP263–279 segments onto a tetravalent Lys2‐Lys‐β‐Ala‐OH core peptide was carried out using Fmoc chemistry. The mass of the RP‐HPLC‐purified synthetic product, 8398 Da, determined by ESI‐MS, was identical to expected mass. Three anti‐rat GH‐BP263–279 MAP antisera, BETO‐8039, BETO‐8040, and BETO‐8041, at dilutions of 10−3, recognized both the rat GH‐BP263–279 MAP and recombinant mouse GH‐BP with ED50s within a range of 5–10 fmol, but did not cross‐react with BSA in dot blot analyses. BETO‐8041 antisera (10−3 dilution) recognized GH‐BPs of rat serum and liver having Mrs ranging from 35 to 130 kDa, but did not recognize full‐length rat GH‐Rs. The antisera also detected recombinant mouse GH‐BPs. In summary, the tetravalent rat GH‐BP263–279 MAP dendrimer served as an effective immunogenic antigen in eliciting high titer antisera specific for the C‐termini of both rat and mouse GH‐BPs. The antisera will facilitate studies aimed at improving our understanding of the biology of GH‐BPs. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd.
A room temperature ionic liquid as convenient solvent for the oxidative folding of conopeptides
Authors: Miloslavina Alesia A. , Leipold Enrico , Kijas Michael , Stark Annegret , Heinemann Stefan H. , Imhof Diana
Published: December 2008

We report the first example of conopeptide oxidation performed in a biocompatible ionic liquid, 1‐ethyl‐3‐methylimidazolium acetate ([C2mim][OAc]), which enables the efficient formation of both hydrophilic and poorly water‐soluble conotoxins compared with conventional methods. Moreover, the method features a high‐concentration approach ultimately leading to higher yields at reduced separation effort. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd.
Between two worlds: local students in higher education and ‘scouse’/student identities
Authors: Holdsworth Clare
Published: December 2008

The restructuring of higher education (HE) finance and concomitant expansion of HE in England have implications for how students are recruited and their experiences of HE. While universities continue to be dominated by traditional entrants, widening participation policies have enabled more students from less‐advantaged backgrounds to study at university. One trend that is emerging as part of these activities is how the traditional expectation of leaving home to go to university is not necessarily being followed by ‘non‐traditional’ entrants, and many choose to study at their local university. This has implications for their experiences of student life as they have to negotiate the assumption that students are not ‘locals’ and vice versa. This paper explores how the assumption of mutual exclusivity of local and student identities is produced and perpetuated through limited interactions between ‘students’ and ‘locals’ and the implications these have for local students, who may find themselves isolated between the two communities. Copyright © 2009 John Wiley & Sons, Ltd.
Researching family migration decision‐making: a children‐in‐families approach
Authors: Bushin Naomi
Published: December 2008

This paper identifies that much geographical research exploring family migration decision‐making has overlooked the issue of children's agency. Motivations for family migration are considered to be influenced by children's presence within families, but it is often assumed that children have no actual involvement in making family migration decisions. In this paper I argue that changes in socio‐cultural constructions of ‘the family’ and ‘childhood’, alongside changes in familial forms and contexts, suggest that population geographers should consider the possibility that some children may be involved in making family migration decisions. I suggest that in order to develop deeper and more nuanced theorisations of family migration decision‐making, which reflect the involvement and experiences of children, a children‐in‐families approach to researching family migration may be fruitful. This approach is outlined in the paper, drawing on the findings of a mixed‐methods family migration research project with 37 families who moved within the UK. A possible framework for exploring children's levels of involvement in family migration decision‐making is introduced, and two key factors that influence their involvement are considered – children's age and parental consideration of children's ‘best interests’. By adopting a children‐in‐families approach to family migration decision‐making, I argue that current understandings of these processes will be furthered and population geographers will be able to contribute to broader debates on children's involvement in decision‐making within family contexts. Copyright © 2009 John Wiley & Sons, Ltd.
Gas‐phase fragmentation study of a novel series of synthetic 2‐oxo‐2H‐benzopyrano[2,3‐d]pyrimidine derivatives using electrospray ionization tandem mass spectroscopy measured with a quadrupole orthogonal time‐of‐flight hybrid instrument
Authors: Turki Hamida , Genestie Benoit , Gharbi Rachid El , Boussiry Sameh El , Banoub Joseph
Published: December 2008

The fragmentation patterns of a series of six novel synthesized benzopyranopyrimidine derivatives 1–6, possessing the same 2‐oxo‐2H‐benzopyrano[2,3‐d]pyrimidine backbone structure, were investigated by electrospray ionization mass spectrometry (ESI‐MS) and tandem mass spectrometry (MS/MS) techniques using a quadrupole orthogonal time‐of‐flight (QqToF)‐hybrid instrument. The series of six pure benzopyranopyrimidine compounds contained three constitutional isobaric isomers (compounds 4–6). A simple methodology, based on the use of ESI (positive ion mode) and increasing the declustering potential in the atmospheric pressure/vacuum interface resulting in collision‐induced dissociation (CID), was used to enhance the formation of the product ions. In general, the novel synthetic benzopyranopyrimidine derivatives 1–6 afforded exact accurate masses for the protonated molecules. This led to the confirmation of both molecular masses and chemical structures of the studied compounds. The breakdown routes of the protonated molecules were rationalized by conducting low‐energy CID‐MS/MS analyses. It was shown that the MS/MS fragmentation routes for the protonated molecules 1 and 2 were similar, and that the MS/MS fragmentations of the constitutional isobaric protonated molecules 5 and 6 were identical. It was also shown that the gas‐phase CID fragmentations of 5 and 6 were different from that of their constitutional isomer 4. Finally, the ESI‐MS and CID‐MS/MS analyses of the protonated molecules that were obtained from the monodeuterated benzopyranopyrimidine derivatives 1–6 confirmed the values obtained for the exact masses, the precise structural assignments of all product ions and all the pathways described in the proposed CID fragmentations. Copyright © 2008 John Wiley & Sons, Ltd.
Proof of the local REM conjecture for number partitioning. II. Growing energy scales
Authors: Borgs Christian , Chayes Jennifer , Mertens Stephan , Nair Chandra
Published: December 2008

We continue our analysis of the number partitioning problem with n weights chosen i.i.d. from some fixed probability distribution with density ρ. In Part I of this work, we established the so‐called local REM conjecture of Bauke, Franz and Mertens. Namely, we showed that, as n → ∞, the suitably rescaled energy spectrum above some fixed scale α tends to a Poisson process with density one, and the partitions corresponding to these energies become asymptotically uncorrelated. In this part, we analyze the number partitioning problem for energy scales αn that grow with n, and show that the local REM conjecture holds as long as n‐1/4αn → 0, and fails if αn grows like κn1/4 with κ > 0.

We also consider the SK‐spin glass model, and show that it has an analogous threshold: the local REM conjecture holds for energies of order o(n), and fails if the energies grow like κn with κ > 0. © 2008 Wiley Periodicals, Inc. Random Struct. Alg., 2009
Hemostatic Step‐by‐Step Procedure to Control Presacral Bleeding During Laparoscopic Total Mesorectal Excision
Authors: D’Ambra Luigi , Berti Stefano , Bonfante Pierfrancesco , Bianchi Claudio , Gianquinto Daniela , Falco Emilio
Published: December 2008

Background

A new procedure of hemostasis during laparoscopic total mesorectal excision is described.

Methods

In our surgical department, from January 2004 to December 2007, 128 patients underwent laparoscopic total mesorectal excision. Among them, 47 patients underwent laparoscopic anterior resection after preoperative radiotherapy, 68 patients underwent laparoscopic anterior resection without preoperative radiotherapy, and 13 patients underwent laparoscopic abdominal perineal amputation.

Results

In seven laparoscopic rectal surgery cases, we encountered unstoppable presacral bleeding, not amenable by conventional hemostatic solutions. In these cases we applied a simple staging hemostatic procedure. We first performed local compression: tamponing with a small gauze or absorbable fabric hemostat. If bleeding did not stop, we localized an epiploic or omental scrap and excised it by using bipolar forceps and use it as a plug on the tip of a grasping forceps. This plug is then put on the bleeding source and monopolar coagulation is applied by electrified dissecting forceps through the interposed grasping forceps. If bleeding did not stop, we used a little scrap of bovine pericardium graft and tacked it to the bleeding site using endoscopic helicoidal protack.

Conclusions

Our experience suggests that this hemostatic step‐by‐step procedure is a valid option to control persistent presacral hemorrhages.
Gender and Elections: An Examination of the 2006 Canadian Federal Election
Authors: Rekkas Marie
Published: December 2008

Abstract. The existing literature on gender effects in the electoral process offers little evidence of significant gender vote share differentials. In this paper it is shown that for the 2006 Canadian federal election, once candidate campaign spending is introduced into the model with appropriate flexibility in the vote share responsiveness across genders, significant differences are found to exist between male and female candidates. The findings suggest that, for equal levels of spending, male incumbents have a vote share advantage relative to female incumbents, though this vote share advantage is found to diminish with increased expenditures. Female non-incumbent candidates, on the other hand, have a vote share advantage over male non-incumbent candidates for higher levels of expenditure and this advantage was found to increase with increased expenditures.

Résumé. Les écrits traitant des effets du genre dans le processus électoral offrent peu de preuves d'un écart significatif dans le pourcentage des voix selon le genre. Cet article montrera que, dans le contexte des élections fédérales canadiennes de 2006, une fois que les dépenses de campagne des candidats sont introduites dans le modèle avec la flexibilité adéquate sur la réceptivité du pourcentage des voix selon les genres, on découvre que des différences significatives existent entre les candidats masculins et féminins. Le résultat des recherches montre que pour des dépenses équivalentes, les titulaires masculins ont un avantage sur le pourcentage des voix par rapport aux titulaires de sexe féminin bien qu'il s'avère que cet avantage diminue lorsque les dépenses augmentent. D'autre part, les candidates féminines non-titulaires ont un avantage sur le pourcentage des voix par rapport aux candidats masculins non-titulaires quand les dépenses sont plus élevées et cet avantage s'avère augmenter lorsque les dépenses augmentent.
Association between the food retail environment surrounding schools and overweight in Canadian youth
Authors: Seliske Laura M , Pickett William , Boyce William F , Janssen Ian
Published: December 2008

Introduction

There is growing interest in how the physical environment influences obesity. Few studies have considered how the food retail environment surrounding schools influences overweight in students.

Objective

To determine whether there is a relationship between food retailers surrounding schools and overweight among Canadian youth.

Design

Cross-sectional study.

Setting/methods/subjects

The number of food retailers was obtained within a 1 km and 5 km radius around 178 schools in Canada. Retailers included full-service restaurants, fast-food restaurants, sub/sandwich retailers, doughnut/coffee shops, convenience stores and grocery stores. An index of total food retailer exposure was also created. Multilevel analyses were used to control for individual- and area-level covariates.

Results

None of the individual food retailers was associated with an increased likelihood of overweight. The total food retailer index was most strongly related to overweight, but in the opposite direction to that hypothesized. At 1 km, students attending schools with at least one food retailer had a lower relative odds of overweight (OR = 0·70, 95 % CI 0·61, 0·81). At 5 km, students attending schools with the highest exposure to the total food retailer index had a lower relative odds of overweight (OR = 0·56, 95 % CI 0·47, 0·68) compared with students attending schools with no exposure.

Conclusions

Exposure to various types of food retailers in school neighbourhoods was not associated with an increased likelihood of overweight in Canadian school-aged youth. The opportunity to make healthy choices from a variety of options and the unique Canadian context may explain the findings.
Ethnic variance in iron status: is it related to dietary intake?
Authors: Wall Clare R , Brunt Deborah R , Grant Cameron C
Published: December 2008

Objective

In New Zealand (NZ), Fe deficiency (ID) is present in 14 % of children aged <2 years. Prevalence varies with ethnicity (NZ European 7 %, Pacific 17 %, Maori 20 %). We describe dietary Fe intake, how this varies with ethnicity and whether intake predicts Fe status.

Design

A random sample of children aged 6–23 months. Usual Fe intake and dietary sources were estimated from 2 d weighed food records. Associations were determined between adequacy of Fe intake, as measured by the Estimated Average Requirement (EAR), and ID.

Subjects

Sampling was stratified by ethnicity. Dietary and blood analysis data were available for 247 children.

Results

The median daily Fe intake was 8·3 mg (age 6–11 months) and 6·3 mg (age 12–23 months). Breast milk and milk formulas (median 58 %; age 6–11 months), and cereals (41 %) and fruit and vegetables (17 %; age 12–23 months), were the predominant dietary sources of Fe. Fe intake was below the EAR for 25 % of the children. Not meeting the EAR increased the risk of ID for children aged 6–11 months (relative risk = 18·45, 95 % CI 3·24, 100·00) and 12–23 months (relative risk = 4·95, 95 % CI 1·59, 15·41). In comparison with NZ European, Pacific children had a greater daily Fe intake (P= 0·04) and obtained a larger proportion of Fe from meat and meat dishes (P= 0·02).

Conclusions

A significant proportion of young NZ children have inadequate dietary Fe intake. This inadequate intake increases the risk of ID. Ethnic differences in Fe intake do not explain the increased risk of ID for Pacific children.
GROUPS AND SEMIGROUPS WITH A ONE-COUNTER WORD PROBLEM
Authors: HOLT DEREK F. , OWENS MATTHEW D. , THOMAS RICHARD M.
Published: December 2008

We prove that a finitely generated semigroup whose word problem is a one-counter language has a linear growth function. This provides us with a very strong restriction on the structure of such a semigroup, which, in particular, yields an elementary proof of a result of Herbst, that a group with a one-counter word problem is virtually cyclic. We prove also that the word problem of a group is an intersection of finitely many one-counter languages if and only if the group is virtually abelian.
RECOGNITION OF SMALL DIMENSIONAL REPRESENTATIONS OF GENERAL LINEAR GROUPS
Authors: MAGAARD KAY , O’BRIEN E. A. , SERESS ÁKOS
Published: December 2008

LetGbe isomorphic to a groupHsatisfying SL(d,q)≤H≤GL(d,q) and letWbe an irreducibleFqG-module of dimension at mostd2. We present a Las Vegas polynomial-time algorithm which takes as inputWand constructs ad-dimensional projective representation ofG.
A NOTE ON PERMUTATION GROUPS AND THEIR REGULAR SUBGROUPS
Authors: XU MING-YAO
Published: December 2008

In this note we first prove that, for a positive integern>1 withn≠porp2wherepis a prime, there exists a transitive group of degreenwithout regular subgroups. Then we look at 2-closed transitive groups without regular subgroups, and pose two questions and a problem for further study.
Composition, microstructures, and petrophysics of the Mozumi fault, Japan: In situ analyses of fault zone properties and structure in sedimentary rocks from shallow crustal levels
Authors: Isaacs Angela J. , Evans James P. , Kolesar Peter T. , Nohara Tsuyoshi
Published: December 2008

We characterize the chemical, microstructural, and geophysical properties of fault‐related rock samples from the 80–100 m wide Mozumi fault zone, north central Honshu, Japan. The fault is exposed in a research tunnel 300–400 m below the ground, and we combine geological data with borehole geophysical logs to determine the elastic and seismic properties of the fault zone. Detailed mapping within the tunnel reveals that the fault zone consists of two zones of breccia to foliated cataclasites 20 and 50 m thick. Two narrow (tens of centimeters wide) principal slip zones on which most of the slip occurred bound the central fault zone. The dominant deformation mechanisms within the fault zone were brittle fracture, brecciation, slip localization, plastic deformation, and vein formation in a sericite‐calcite rich matrix. Clay alteration patterns are complex within the fault zone, with clay‐rich fault breccia enriched in smectite, illite, and kaolinite relative to the kaolinite and illite dominant in the host rock. Whole rock geochemical analyses show that the fault‐related rocks are depleted in Fe, Na, K, Al, Mg, and Si relative to the host rock. The fault zone exhibits depressed electrical resistivity values by 10–100 ohm m relative to the wall rock, values of Vp and Vs values that are ∼0.30 and ∼0.40 km/s (10–20%) less than protolith values. The spontaneous potential logs indicate that the fault zone has increased freshwater content relative to formation waters. Wellbore‐based measurements of Vp and Vs in fault‐related rocks to enable us to calculate values of Young's modulus from 16.2 to 44.9 GPa and Poisson's ratio for the fault zone of 0.263 to 0.393. The protolith has Young's modulus of 55.4 GPa and a Poisson's ratio of 0.242. Lowest calculated values of Young's modulus and highest calculated values of Poisson's ratio correspond to fault breccia with increased porosity, high fluid content, and low resistivity values. Taken together, these data show that the shallow portion of the Mozumi fault consists of a complex zone of anastomosing narrow slip zones that bound broad zones of damage. Fluid‐rock alteration and deformation created altered fault‐related rocks, which have resulted in overall reduced interval velocities of the fault zone. These data indicate that seismic waves traveling along the interface or internally reflected in the fault zone would encounter rocks of differing and reduced elastic properties relative to the host rocks but that in detail, material properties within the fault may vary.
Heliospheric sector boundaries: Single or multiple?
Authors: Neugebauer Marcia
Published: December 2008

Solar wind data were examined for a period when the Ulysses spacecraft moved roughly parallel to the boundary between inward and outward interplanetary fields at a solar distance of 1.4 AU. Multiple crossings of the magnetic sector boundary were observed. Three tests were used to evaluate whether or not the crossings were due to multiple crossings of a single surface or single crossings of separate surfaces: (1) a correlation between the latitude and longitude directions of the normals to the surface, (2) the radius of curvature of the surface calculated from consecutive crossings, and (3) the variation of plasma parameters across the surfaces. Both multiple crossings of a single rippled surface and single crossings of multiple boundary surfaces were observed.
Crystallographic preferred orientation produced by diffusional creep of harzburgite: Effects of chemical interactions among phases during plastic flow
Authors: Sundberg Marshall , Cooper Reid F.
Published: December 2008

Experimental deformation experiments have been conducted on fine‐grained, two‐phase aggregates of olivine and orthopyroxene to investigate the role of grain and phase boundary sliding on rheology and fabric development. A suite of large‐strain (γ ≥ 1) general shear experiments conducted at T = 1200°C and P = 1.6 GPa on aggregates ranging from 65 to 0 vol % orthopyroxene, to characterize the evolution of fabric, were complemented by small‐strain axial compression experiments at T = 1200°C and P = 0.3 GPa, to better constrain the rheology. Microstructural and rheological data suggest that deformation of these two‐phase aggregates in the diffusion creep regime occurs via interface‐reaction‐controlled diffusion creep that is accompanied by extensive migration of olivine‐orthopyroxene phase boundaries. The resulting rheologies suggest that olivine + orthopyroxene composites are weaker than the olivine end‐member at the conditions tested. Physically, this behavior arises because long‐range, i.e., grain‐scale, diffusion of Si4+ is unnecessary in these pseudobinary two‐phase aggregates. We further demonstrate that interface‐controlled diffusion creep leads to strong crystallographic preferred orientations (CPO) of the component minerals, which develops in the near absence of dislocation activity. The CPO formed in these anhydrous, low‐stress experiments has the olivine a axis aligned perpendicular to the flow direction (“type B” fabric) argued by some to be the unique result of deformation under conditions of high differential stress and high water fugacity. Phase boundary dynamics, thus, are argued as a significant factor in the accumulation of strain in polyphase aggregates.
The molecular machinery of Keilin's respiratory chain
Authors: Rich P.R.
Published: December 2008

Keilin's classic paper of 1925 [Keilin (1925) Proc. R. Soc. London Ser. B 100, 129–151], achieved with simple, but elegant, techniques, describes the cytochrome components of the respiratory chain and their roles in intracellular respiration and oxygen consumption. Since that time, a tremendous amount of work has clarified the intricate details of the prosthetic groups, cofactors and proteins that comprise the respiratory chain and associated machinery for ATP synthesis. The work has culminated in advanced crystallographic and spectroscopic methods that provide structural and mechanistic details of this mitochondrial molecular machinery, in many instances to atomic level. I review here the current state of understanding of the mitochondrial respiratory chain in terms of structures and dynamics of the component proteins and their roles in the biological electron and proton transfer processes that result in ATP synthesis. These advances, together with emerging evidence of further diverse roles of mitochondria in health and disease, have prompted a new era of interest in mitochondrial function.
The glucose–fatty acid cycle: a physiological perspective
Authors: Frayn K.N.
Published: December 2008

Glucose and fatty acids are the major fuels for mammalian metabolism and it is clearly essential that mechanisms exist for mutual co-ordination of their utilization. The glucose–fatty acid cycle, as it was proposed in 1963, describes one set of mechanisms by which carbohydrate and fat metabolism interact. Since that time, the importance of the glucose–fatty acid cycle has been confirmed repeatedly, in particular by elevation of plasma non-esterified fatty acid concentrations and demonstration of an impairment of glucose utilization. Since 1963 further means have been elucidated by which glucose and fatty acids interact. These include stimulation of hepatic glucose output by fatty acids, potentiation of glucose-stimulated insulin secretion by fatty acids, and the cellular mechanism whereby high glucose and insulin concentrations inhibit fatty acid oxidation via malonyl-CoA regulation of carnitine palmitoyltransferase-1. The last of these mechanisms, discovered by Denis McGarry and Daniel Foster in 1977, provides an almost exact complement to the mechanism described in the glucose–fatty acid cycle whereby high concentrations of fatty acids inhibit glucose utilization. These additional discoveries have not detracted from the important of the glucose–fatty acid cycle: rather, they have reinforced the importance of mechanisms whereby glucose and fat can interact.
VEGF signalling: integration and multi-tasking in endothelial cell biology
Authors: Zachary I.
Published: December 2008

The central role of VEGF (vascular endothelial growth factor A) in angiogenesis is dependent upon its ability to co-ordinately regulate multiple endothelial functions. The multifunctionality of VEGF at the cellular level results from its ability to initiate a diverse, complex and integrated network of signalling pathways via its major receptor, kinase-insert-domain-containing receptor (KDR). Activation of phospholipase C-γ, protein kinase C, Ca2+, ERK (extracellular-signal-regulated protein kinase), Akt, Src, focal adhesion kinase and calcineurin pathways has been implicated in mediating multiple VEGF functions, including survival, proliferation, migration, vascular permeability, tubulogenesis, NO and prostanoid synthesis, and gene expression. NO and prostanoids in turn play paracrine and autocrine roles in linking post-receptor signalling to biological functions. Integration between biologically important signalling cascades occurs at several points. Akt and ERK, for example, are key junction points linking together signal transduction involved in survival and NO generation, and proliferation and prostanoid biosynthesis. Together, the multiplicity, functional versatility and integration of VEGF signalling provide a useful framework for understanding the mechanisms underlying the endothelial biological response to this key factor.
Exogenous and intracellularly generated sphingosine 1-phosphate can regulate cellular processes by divergent pathways
Authors: Spiegel S. , Milstien S.
Published: December 2008

S1P (sphingosine 1-phosphate) is the ligand for a family of specific G-protein-coupled receptors that regulate a wide variety of important cellular functions, including vascular maturation, angiogenesis, cell growth, survival, cytoskeletal rearrangements and cell motility. However, S1P also may have intracellular functions. In this review, we discuss two examples that clearly indicate that intracellularly generated and exogenous S1P can regulate biological processes by divergent pathways.
Maintaining the permeability barrier during protein trafficking at the endoplasmic reticulum membrane
Authors: Johnson A.E.
Published: December 2008

Many proteins are translocated across or integrated into a cellular membrane without disrupting its integrity, although it is difficult to imagine how such macromolecular transmembrane movement can occur without simultaneously allowing significant small-molecule and ion diffusion across the bilayer. Recent studies have identified some molecular mechanisms that are involved in maintaining the permeability barrier of the endoplasmic reticulum membrane during co-translational protein translocation and integration. These mechanisms are both simple and direct in concept, but are operationally complex and require the co-ordinated and regulated interaction of several multicomponent complexes.
Getting to the membrane: how is co-translational protein targeting to the endoplasmic reticulum regulated?
Authors: Pool M.R.
Published: December 2008

Co-translational protein targeting to the endoplasmic reticulum requires the signal-recognition particle, its cognate receptor and the translocation channel. Co-ordination of the targeting process necessitates the interaction of these components with each other and with the ribosome. These interactions are regulated by three GTPases, which act in concert, ensuring the fidelity of the targeting process.
Making membrane proteins at the mammalian endoplasmic reticulum
Authors: Lecomte F.J.L. , Ismail N. , High S.
Published: December 2008

Whereas protein biogenesis at the endoplasmic reticulum is well understood in the case of secretory proteins and simple membrane proteins, much less is known about the synthesis of multi-spanning integral membrane proteins. While it is clear that the multiple membrane-spanning domains of these proteins must be inserted into the lipid bilayer during biosynthesis, the mechanism by which their integration is achieved and their subsequent folding/assembly are poorly defined. In this review, we summarize our current understanding of protein synthesis at the endoplasmic reticulum and highlight specific features that are relevant to the biogenesis of multi-spanning membrane proteins.
Nutritional status, metabolic responses to exercise and implications for performance
Authors: Maughan R.J.
Published: December 2008

Diet can significantly influence exercise performance. Diet alone will not ensure successful performance in sport, but it plays a permissive role in allowing sustained intensive training with limited risk of illness and injury. Diet may also promote adaptations to training by stimulating synthesis and breakdown of the specific proteins that respond to the training stimulus. Protein synthesis and breakdown are both stimulated for some time after exercise, and protein ingestion before, during or immediately after exercise will enhance the fractional synthetic rate. Carbohydrate and fat are key energy substrates during exercise, and acute nutritional manipulation will affect both substrate selection and exercise performance.