bluuebunny/crossref_metadata_2025 huggingface dataset:
Stability boundary analysis of the dynamic voltage restorer in weak systems with dynamic loads
Authors: Segundo‐Ramírez Juan , Medina Aurelio , Ghosh Arindam , Ledwich Gerard
Published: January 2011

In this contribution, a stability analysis for a dynamic voltage restorer (DVR) connected to a weak ac system containing a dynamic load is presented using continuation techniques and bifurcation theory. The system dynamics are explored through the continuation of periodic solutions of the associated dynamic equations. The switching process in the DVR converter is taken into account to trace the stability regions through a suitable mathematical representation of the DVR converter. The stability regions in the Thevenin equivalent plane are computed. In addition, the stability regions in the control gains space, as well as the contour lines for different Floquet multipliers, are computed. Besides, the DVR converter model employed in this contribution avoids the necessity of developing very complicated iterative map approaches as in the conventional bifurcation analysis of converters. The continuation method and the DVR model can take into account dynamics and nonlinear loads and any network topology since the analysis is carried out directly from the state space equations. The bifurcation approach is shown to be both computationally efficient and robust, since it eliminates the need for numerically critical and long‐lasting transient simulations. Copyright © 2011 John Wiley & Sons, Ltd.
Annual banned‐substance review: analytical approaches in human sports drug testing
Authors: Thevis Mario , Kuuranne Tiia , Geyer Hans , Schänzer Wilhelm
Published: January 2011

The timely update of the list of prohibited substances and methods of doping (as issued by the World Anti‐Doping Agency) is an essential aspect of international anti‐doping efforts and represents consensual agreement by expert panels regarding substances and the methods of performance manipulation in sports. The annual banned‐substance review for human doping controls critically summarizes recent innovations in analytical approaches; its purpose is to improve the quality of doping controls by reporting emerging and advancing methods that focus on detecting known and recently outlawed substances. This review surveys new and/or enhanced procedures and techniques of doping analysis together with information relevant to doping control that has been published in the literature between October 2009 and September 2010. Copyright © 2011 John Wiley & Sons, Ltd.
A New Route to Azadithiolato Complexes
Authors: Angamuthu Raja , Carroll Maria E. , Ramesh Maya , Rauchfuss Thomas B.
Published: January 2011

The reaction of [(MeC5H4)2Ti(SH)2] with cyclic imines with the formula (CH2NR)3 gives 2‐aza‐1,3‐dithiolato chelate complexes [(MeC5H4)2Ti{(SCH2)2NR}] (1, R = Ph; 2, R = Me; 3, R = CH2Ph). These compounds demonstrate that azadithiolate ligands can exist on mononuclear metal centers. The complexes were characterized by 1H NMR spectroscopy, ESI‐mass spectrometry, and X‐ray crystallography. Variable‐temperature 1H NMR studies reveal that the dithiolate ligands undergo ring inversion like other dithiatitanacyclohexanes. Treatment of [(MeC5H4)2Ti{(SCH2)2NPh}] (1) with [Fe(benzylideneacetone)(CO)3] afforded [Fe2{(SCH2)2NPh}(CO)6] in good yield.
Results of a prospective study of positron emission tomography–directed management of residual nodal abnormalities in node‐positive head and neck cancer after definitive radiotherapy with or without systemic therapy
Authors: Porceddu Sandro V. , Pryor David I. , Burmeister Elizabeth , Burmeister Bryan H. , Poulsen Michael G. , Foote Matthew C. , Panizza Benedict , Coman Scott , McFarlane David , Coman William
Published: January 2011

Background

The purpose of this study was to present our prospectively evaluated positron emission tomography (PET)‐directed policy for managing the neck in node‐positive head and neck squamous cell carcinoma (N+HNSCC) after definitive radiotherapy (RT) with or without concurrent systemic therapy.

Methods

One hundred twelve consecutive patients who achieved a complete response at the primary site underwent a 12‐week posttherapy nodal response assessment with PET and diagnostic CT. Patients with an equivocal PET underwent a repeat PET 4 to 6 weeks later. Patients with residual CT nodal abnormalities deemed PET‐negative were uniformly observed regardless of residual nodal size.

Results

Median follow‐up from commencement of RT was 28 months (range, 13–64 months). Residual CT nodal abnormalities were present in 50 patients (45%): 41 PET‐negative and 9 PET‐positive. All PET‐negative residual CT nodal abnormalities were observed without subsequent isolated nodal failure.

Conclusion

PET‐directed management of the neck after definitive RT in node‐positive HNSCC appropriately spares neck dissections in patients with PET‐negative residual CT nodal abnormalities. © 2011 Wiley Periodicals, Inc. Head Neck, 2011
Role of parathyroid hormone monitoring during parathyroidectomy
Authors: Bachar Gideon , Mizrachi Aviram , Hadar Tuvia , Feinmesser Raphael , Shpitzer Thomas
Published: January 2011

Background

The value of intraoperative parathyroid hormone (IOPTH) monitoring in parathyroidectomy has been previously debated.

Methods

This retrospective analysis was of 240 patients, operated on for primary hyperparathyroidism (PHPT) between January 2002 and January 2006 and categorized into 3 groups by preoperative and intraoperative modalities: group 1 (n = 109), technetium 99m sestamibi (MIBI), ultrasonography, and IOPTH; group 2 (n = 102), ultrasonography and MIBI; and group 3 (n = 29), ultrasonography and IOPTH. Sensitivity and specificity were calculated.

Results

In group 1, IOPTH increased the success rate from 97% to 99%. In group 2, ultrasonography and MIBI were concordant in 95% of cases. In group 3, IOPTH increased the sensitivity from 89% to 96%. The duration of surgery was longer (p < .0001) when IOPTH was applied.

Conclusions

When ultrasonography and MIBI are used, the additional benefit of IOPTH is marginal, especially given the longer duration of surgery. Ultrasonography and additional IOPTH yield good success rates when MIBI is not available. © 2011 Wiley Periodicals, Inc. Head Neck, 2011
The motivation of information technology consultants: The struggle with social dimensions and identity
Authors: Wallgren Lars Göran , Hanse Jan Johansson
Published: January 2011

Increasingly, customer companies hire external information technology (IT) consultants, often on a special project basis. These consultants are employees of professional service firms, although they receive their assignments from the hiring companies, report to them, and are supervised by them. Using semistructured interviews with 12 IT consultants in Sweden, we examine the factors that influence their work motivation, including the effect of this dual allegiance—to the service firm and to the customer company. The data indicate that the primary motivators are the variety in tasks and the opportunity to influence and/or manage an entire project. Neither monetary incentives nor the consultancy firm norms are strong motivators. A factor that affects work behavior and motivation is the subordinate identity that IT consultants must assume with their powerful clients. The article concludes with practical suggestions for managers who seek to understand what motivates employees who work at a distance, under external control. © 2011 Wiley Periodicals, Inc.
Processing Chemical and Photonic Signals by Artificial Multicomponent Molecular Systems
Authors: Baroncini Massimo , Semeraro Monica , Credi Alberto
Published: January 2011

Miniaturization has been an essential ingredient in the outstanding progress of information technology over the past fifty years. The next, perhaps ultimate, limit of miniaturization is that of molecules, which are the smallest entities with definite size, shape, and properties. Molecular‐level systems that respond to external stimulation by changing some physical or chemical properties can be viewed as input–output devices and therefore may be useful for transferring, processing, and storing information. Some of these nanoscale devices can, in fact, perform logic operations of remarkable complexity. This research — although far from being transferred into technology — is attracting interest, since the nanometer realm seems to be out of reach for the “top‐down” techniques currently available to microelectronics industry. Leaving aside futuristic speculations related to the construction of a chemical computer, molecular logic devices could be interesting for specific applications in areas such as diagnostics, medicine, and materials science, where problems need to be addressed in places — for example, inside a cell — that are out of reach for a silicon‐based computer. Here we discuss the idea of processing information with artificial multicomponent molecular systems in solution by illustrating a few recent examples developed in our laboratory.
Research in progress conference for hospitalists provides valuable peer mentoring
Authors: Abougergi Marwan S. , Wright Scott M. , Landis Regina , Howell Eric E.
Published: January 2011

BACKGROUND:

Many academic hospitalist units lack senior mentors. In such groups, peer mentoring may be valuable. To formalize collaboration, we instituted a research‐in‐progress conference at our institution, and this article describes the format and evaluation data.

METHODS:

The research‐in‐progress sessions were held every 3 to 4 weeks and followed a specific format. Evaluation forms were completed after each of the 15 sessions during the 2009 academic year. Attendees and presenters completed surveys at the end of the sessions. The projects presented were tracked for successful academic outcomes, namely, publication in a peer‐reviewed journal or presentation at a national meeting.

RESULTS:

A mean of 9.6 persons were present at each session and completed the evaluations. All 15 presenters rated the climate of the sessions as extremely supportive, and 86% believed they were helpful in advancing their project. A total of 143 evaluations were completed by the attendees, 86% and 96% of whom found the sessions to be intellectually stimulating and to have satisfactorily kept them abreast of their colleagues' scholarly pursuits, respectively. To date, 10 of the 15 projects have translated into successful academic outcomes: 6 peer‐reviewed publications and 4 other presentations presented at national meetings.

CONCLUSIONS:

The research‐in‐progress conference has been well received and has resulted in academic productivity within our hospitalist division. It is likely that such a conference will be most valuable for groups with limited access to senior mentors. Journal of Hospital Medicine 2011;6:43–46. © 2011 Society of Hospital Medicine
Lucid dreaming and resilience in the face of exposure to terrorism
Authors: Soffer‐Dudek Nirit , Wertheim Reut , Shahar Golan
Published: January 2011

The relationship between resilience and lucid dreams, which involves awareness of the experience of dreaming, was examined in 79 Israeli young adults. Psychological distress and lucid dreams 3 years prior to exposure to terrorism, and exposure levels and psychological distress 1 week following exposure, were assessed. Both indirect exposure through media and perceived stress predicted an increase in distress during the 3‐year interval under low, but not high, levels of lucid dreams. Possible mechanisms are discussed.
A randomized, controlled study of treatment for alcohol dependence in patients awaiting liver transplantation
Authors: Weinrieb Robert M. , Van Horn Deborah H.A. , Lynch Kevin G. , Lucey Michael R.
Published: January 2011

Alcohol is the second most common cause of cirrhosis necessitating liver transplantation in the United States, yet rates of posttransplant drinking approach 50% and no controlled clinical trials of alcoholism treatment exist in this population. Eligible patients were randomly assigned to receive Motivational Enhancement Therapy (MET), or referral to local treatment sources (“treatment as usual” [TAU]). Addictive behavior, mood states, and general health were compared. Candor concerning alcohol use was encouraged by keeping drinking questionnaires in confidence, except in medical emergencies. Ninety-one subjects were studied; 46 received MET, 45 received TAU, 29 proceeded to transplantation (MET, n = 13; TAU, n = 16). A total of 69 subjects completed 24 weeks of observation, and 25 subjects were assessed at 96 weeks. No difference in study attendance was observed, but significantly more MET subjects attended 1 or more treatment sessions. Twenty-three subjects (25% of sample) drank after randomization but before transplant. Excluding an extreme outlier, MET drinkers had significantly fewer drinks per drinking days than TAU drinkers. Neither treatment plan resulted in significant variances in measures of psychosocial health. In conclusion, although MET afforded no significant benefit over TAU for mood or general health outcomes, this study provides some degree of support for MET to limit the quantity and frequency of pretransplant alcohol consumption among liver transplant candidates with alcohol dependence. However, because of the limited number of study subjects, these data must be interpreted cautiously. Further research to validate our findings or to identify better methods to identify and intervene with patients at risk of pretransplant and posttransplant drinking should continue. Liver Transpl 17:539-547, 2011. © 2011 AASLD.
Mobilization of hepatic mesenchymal stem cells from human liver grafts
Authors: Pan Qiuwei , Fouraschen Suomi M.G. , Kaya Fatima S. F. Aerts , Verstegen Monique M. , Pescatori Mario , Stubbs Andrew P. , van IJcken Wilfred , van der Sloot Antoine , Smits Ron , Kwekkeboom Jaap , Metselaar Herold J. , Kazemier Geert , de Jonge Jeroen , Tilanus Hugo W. , Wagemaker Gerard , Janssen Harry L.A. , van der Laan Luc J.W.
Published: January 2011

Extensive studies have demonstrated the potential applications of bone marrow-derived mesenchymal stem cells (BM-MSCs) as regenerative or immunosuppressive treatments in the setting of organ transplantation. The aims of the present study were to explore the presence and mobilization of mesenchymal stem cells (MSCs) in adult human liver grafts and to compare their functional capacities to those of BM-MSCs. The culturing of liver graft preservation fluids (perfusates) or end-stage liver disease tissues resulted in the expansion of MSCs. Liver-derived mesenchymal stem cells (L-MSCs) were equivalent to BM-MSCs in adipogenic and osteogenic differentiation and in wingless-type-stimulated proliferative responses. Moreover, the genome-wide gene expression was very similar, with a 2-fold or greater difference found in only 82 of the 32,321 genes (0.25%). L-MSC differentiation into a hepatocyte lineage was demonstrated in immunodeficient mice and in vitro by the ability to support a hepatitis C virus infection. Furthermore, a subset of engrafted MSCs survived over the long term in vivo and maintained stem cell characteristics. Like BM-MSCs, L-MSCs were found to be immunosuppressive; this was shown by significant inhibition of T cell proliferation. In conclusion, the adult human liver contains an MSC population with a regenerative and immunoregulatory capacity that can potentially contribute to tissue repair and immunomodulation after liver transplantation. Liver Transpl 17:596-609, 2011. © 2011 AASLD.
Graft rotation and late portal vein complications in pediatric living donor liver transplantation using left-sided grafts: Long-term computed tomography observations
Authors: Moon Suk-Bae , Moon Ju-Ik , Kwon Choon-Hyuk David , Kim Sung-Joo , Seo Jeong-Meen , Joh Jae-Won , Lee Suk-Koo
Published: January 2011

Right-side rotation of the graft is an uncommon event after pediatric living donor liver transplantation (LDLT) with a left-sided graft. However, graft rotation might lead to gradual portal vein (PV) stretching and late portal vein complications (PVCs). The goal of this study was to quantify the degree of graft rotation (R) by computed tomography (CT) and to determine the effect of graft rotation on the development of late PVCs. One hundred ten patients underwent LDLT with left-sided grafts between 1996 and 2009; CT images were available and were reviewed for 66 of these patients. To quantify R, the following variables were measured with CT: the longest distance between the midline and the extrahepatic PV at the level of the hepatic hilum (A), the distance between the midline and the center of the superior mesenteric vein at the level of the confluence of the splenic vein and superior mesenteric vein (B), and the inner transverse diameter of the body cavity at the level at which A was measured (C). R was calculated as (A − B)/C. In patients with a patent PV (n = 59) and in patients with late PVCs (n = 7), the median R values were 0.16 (range = 0.03-0.38) and 0.25 (range = 0.13-0.39), respectively; there was a significant difference between the 2 groups (P = 0.003). Multivariate analysis showed that R ≥ 0.2 was the only independent risk factor for the development of late PVCs (P = 0.021). In conclusion, the gradual stretching of the PV after right-side rotation of left-sided grafts might play an important role in the development of late PVCs. PV patency should be closely monitored when graft rotation is noted during clinical follow-up. Liver Transpl 17:717-722, 2011. © 2011 AASLD.
Development of a disease-specific questionnaire to measure health-related quality of life in liver transplant recipients
Authors: Saab Sammy , Ng Vivian , Landaverde Carmen , Lee Sung-Jae , Comulada Scott W. , Arevalo Jennifer , Durazo Francisco , Han Steven-Huy , Younossi Zobari , Busuttil Ronald W.
Published: January 2011

Currently, no disease-targeted instrument is available for measuring health-related quality of life (HRQOL) in liver transplant recipients. We developed and tested a post-liver transplant quality of life (pLTQ) instrument. Item selection for the pLTQ instrument was based on responses from liver transplant recipients, 12 liver experts, and a literature search. Impact scores were generated, and a factor analysis was conducted to organize the items into domains. Questions were constructed for each item, and redundant questions were removed. The pLTQ instrument was initially administered to 196 liver transplant patients and then was again administered to 77 patients 6 to 9 months later with a generic HRQOL survey [Medical Outcomes Study Short Form 36 (SF-36)]. Analysis of variance was used to compare the scores of patients at different times since transplantation and with various indications for transplantation. After redundancies were eliminated, the pLTQ instrument included 32 items in 8 domains: Emotional Function, Worry, Medications, Physical Function, Healthcare, Graft Rejection Concern, Financial, and Pain. We found stable pLTQ instrument and SF-36 instrument scores over time. Data 6 to 9 months after the initial assessment indicated stable quality of life outcomes. The pLTQ instrument is applicable to a variety of liver transplant recipients. The questionnaire was tested with a cross-sectional and longitudinal approach. Liver Transpl 17:567-579, 2011. © 2011 AASLD.
Lipovitellin constitutes the protein backbone of glycoproteins involved in sperm–egg interaction in the amphibian Discoglossus pictus
Authors: Campanella C. , Caputo M. , Vaccaro M.C. , De Marco N. , Tretola L. , Romano M. , Prisco M. , Camardella L. , Flagiello A. , Carotenuto R. , Limatola E. , Polzonetti‐Magni A. , Infante V.
Published: January 2011

Our knowledge of the molecules that interact with sperm at the egg membrane is restricted to a short list. In the eggs of Discoglossus pictus, fusion with sperm is limited to a differentiated structure, the dimple, offering several advantages for detecting molecules involved in fertilization. Previous studies have identified fucosylated glycoproteins of 200, 260, and 270 kDa located at the surface of the dimple that are able to bind sperm in vitro. Here, we show that dimple glycoproteins and a protein represented by a 120‐kDa band released following gel‐into‐gel SDS–PAGE of both glycoproteins share the same N‐terminal amino acid sequence, which itself is similar to the N‐termini of Xenopus liver‐synthesized vitellogenin (VTG) and the lipovitellin 1. MALDI/MS mass spectrometry indicated that the 120‐kDa band is part of both gps 200 and 270/260. A 117‐kDa major protein of the egg lysate exhibits the same MALDI/MS spectrum, and LC‐MSMS indicates that this is a lipovitellin 1 (DpLIV) that coincides with the 120‐kDa band and is responsible for the formation of the 200–270‐kDa dimers. Therefore, lipovitellin 1 constitutes the protein backbone of the dimple glycoconjugates. In vitro assays using polystyrene beads coated with DpLIV or with its dimers indicate that significant sperm binding occurs only with DpLIV dimers. In amphibians, VTG is taken up by the oocyte, where it releases lipovitellins destined to form yolk. In Discoglossus, our data suggest that yolk proteins are also synthesized by the oocyte. The dimple forms in the ovulated oocyte following the exocytosis of vesicles that likely expose DpLIVs at their membrane. Indeed, in whole mounts of immunostained eggs, anti‐vitellogenin antibodies label only the surface of the dimple. Mol. Reprod. Dev. 78:161–171, 2011. © 2011 Wiley‐Liss, Inc.
Silencing of Rieske iron–sulfur protein using chemically synthesised siRNA as a potential biopesticide against Plutella xylostella
Authors: Gong Liang , Yang Xiuqun , Zhang Biliang , Zhong Guohua , Hu MeiYing
Published: January 2011

BACKGROUND: Extensive applications and frequent long‐term use of pesticides can affect behavioural mechanisms and physiological and biochemical aspects of insects, leading to resistance. However, insect control strategies involving a different mode of action would be valuable for managing the emergence of insect resistance. In this context, the development of RNA interference technology has brought a turning point in the creation of new biopesticides.

RESULTS: Full‐length cDNA of Rieske iron–sulfur protein (RISP) was cloned and characterised from Plutella xylostella L. Three siRNAs specific to RISP sequences were designed and chemically synthesised, and fed to P. xylostella larvae by coating cabbage leaves. This resulted in specific gene silencing of RISP, and consequently brought significant mortality of P. xylostella larvae compared with the control treatment. Silencing of RISP leads to significantly lower transcript levels of RISP compared with the control. In addition, the amount of ATP in the surviving larvae was lower than in the control. However, surviving larvae gradually recovered to normal transcript and protein levels.

CONCLUSION: This is the first demonstration of the potential use of chemically synthesised siRNA in the development of new biopesticides as a mitochondrial electron transport inhibitor. Copyright © 2011 Society of Chemical Industry
Addressing multicollinearity in semiconductor manufacturing
Authors: Chang Yu‐Ching , Mastrangelo Christina
Published: January 2011

When building prediction models in the semiconductor environment, many variables, such as input/output variables, have causal relationships which may lead to multicollinearity. There are several approaches to address multicollinearity: variable elimination, orthogonal transformation, and adoption of biased estimates. This paper reviews these methods with respect to an application that has a structure more complex than simple pairwise correlations. We also present two algorithmic variable elimination approaches and compare their performance with that of the existing principal component regression and ridge regression approaches in terms of residual mean square and R2. Copyright © 2011 John Wiley & Sons, Ltd.
State feedback stabilization of stochastic nonlinear systems with SiISS inverse dynamics
Authors: Duan Na , Xie Xue‐Jun , Yu Xin
Published: January 2011

This paper further considers a more general class of stochastic nonlinear systems with stochastic integral input‐to‐state stability (SiISS) inverse dynamics and drift and diffusion terms depending upon the other states besides stochastic inverse dynamics and the first state. By skillfully choosing the designed functions and the update laws of parameters, and using the important mathematical tools established in IEEE Trans. Automat. Contr. 2010; 55(2):304–320, a unifying framework of state feedback controller is proposed to guarantee that all the signals of the closed‐loop system are bounded almost surely and the states can be regulated to zero almost surely. A simulation example demonstrates the effectiveness of the control scheme. Copyright © 2011 John Wiley & Sons, Ltd.
Bayesian inference of gene–environment interaction from incomplete data: What happens when information on environment is disjoint from data on gene and disease?
Authors: Gustafson Paul , Burstyn Igor
Published: January 2011

Inference in gene–environment studies can sometimes exploit the assumption of Mendelian randomization that genotype and environmental exposure are independent in the population under study. Moreover, in some such problems it is reasonable to assume that the disease risk for subjects without environmental exposure will not vary with genotype. When both assumptions can be invoked, we consider the prospects for inferring the dependence of disease risk on genotype and environmental exposure (and particularly the extent of any gene–environment interaction), without detailed data on environmental exposure. The data structure envisioned involves data on disease and genotype jointly, but only external information about the distribution of the environmental exposure in the population. This is relevant as for many environmental exposures individual‐level measurements are costly and/or highly error‐prone. Working in the setting where all relevant variables are binary, we examine the extent to which such data are informative about the interaction, via determination of the large‐sample limit of the posterior distribution. The ideas are illustrated using data from a case–control study for bladder cancer involving smoking behaviour and the NAT2 genotype. Copyright © 2011 John Wiley & Sons, Ltd.
Work–home interference and the relationship with job characteristics and well‐being: a South African study among employees in the construction industry
Authors: Mostert Karina , Peeters Maria , Rost Izel
Published: January 2011

Although the relationship between job characteristics, work–home interference (WHI) and work‐related well‐being has been researched in Western societies, this relationship has not often been tested in non‐Western societies such as South Africa and among low‐wage non‐professional workers, like construction workers. The aim of this study was to test the mediating effect of negative and positive WHI in the relationship between job characteristics (job demands and job resources) and work‐related well‐being (burnout and work engagement) in a sample of 528 employees in the construction industry in South Africa. Structural equation modelling showed that, as expected, job demands and job resources were partially related to burnout, both directly and indirectly through negative WHI. Similarly, job resources were partially related to work engagement, both directly and indirectly, through positive WHI. It can be concluded that these results extend previous research by showing that the relationships between job characteristics, WHI and well‐being hold true for low‐wage workers in a non‐Western society. Copyright © 2011 John Wiley & Sons, Ltd.
Concise Review: Making a Retina—From the Building Blocks to Clinical Applications
Authors: Wallace Valerie A.
Published: January 2011

The retina is the neural tissue located at the back of the eye that captures and processes light and transmits this information to visual processing centers in the brain, which enables us to see. Basic research in retinal development has provided important insight on the control of cell fate, proliferation, and neurogenesis in the central nervous system. This review summarizes the major cellular and molecular events that occur during retinal development and highlights how this knowledge may be harnessed for new therapeutic strategies to treat retinal disease.
Handover approaches for seamless mobility management in next generation wireless networks
Authors: Magagula Linoh A. , Chan H. Anthony , Falowo Olabisi E.
Published: January 2011

Next generation wireless networks (NGWN) will be an integration of heterogeneous wireless access networks that will interwork over an IP‐based infrastructure. This all‐IP vision has led to the development of handover mechanisms to support seamless mobility for active network services among the different interworking wireless networks in order to ensure network access ubiquity in NGWN. These handover mechanisms need to ensure that mobile devices continue to receive ongoing communication without any noticeable disruption during handover events among the heterogeneous networks. This paper gives a qualitative and quantitative review of current handover approaches of IP mobility management protocols for NGWN with an objective to introduce a new way of further optimizing the handover performance. In particular, the paper focuses on handover approaches of mobile IPv6 (MIPv6) based mobility management protocols. Thus, the need, benefits, and limitations of these handover approaches are explored. Thereafter, dynamic handover coordination is introduced as a new viable solution that exploits the benefits and mitigates the limitations of these handover approaches hence improving handover performance in terms of handover delay, packet loss, and signaling overhead. Copyright © 2011 John Wiley & Sons, Ltd.
Fast data access and energy‐efficient protocol for wireless data broadcast
Authors: Shin Haw‐Yun , Yen Mao‐Hsu , Tseng Chih‐Cheng , Liu Hung‐Huan
Published: January 2011

In wireless mobile computing environments, broadcasting is an effective and scalable technique to disseminate information to a massive number of clients, wherein the energy usage and responsiveness are considered major concerns. Existing air indexing schemes for data broadcast have focused on energy efficiency (reducing tuning time) only. On the other hand, existing broadcast scheduling schemes have aimed at reducing access latency through nonflat data broadcast to improve responsiveness only. Not much work has addressed the energy efficiency and responsiveness issues concurrently. In this paper, we propose a fast data access scheme concurrently supporting energy saving protocol that constructs the broadcast channels according to the access frequency of each type of message in order to improve energy efficiency in mobile devices (MDs). The pinwheel scheduling algorithm (PSA) presented in this paper is used to organize all types of messages in the broadcast channel in the most symmetrical distribution in order to reduce both the tuning and access time. The performance of the proposed mechanism is analyzed, and the improvement over existing methods is demonstrated numerically. The results show that the proposed mechanism is capable of improving both the tuning and access time due to the presence of skewness in the access distribution among the disseminated messages. Copyright © 2011 John Wiley & Sons, Ltd.
Content creation in virtual worlds to support adolescent identity development
Authors: Beals Laura M.
Published: January 2011

Virtual worlds are online graphical environments that are becoming an increasingly large part of the online experience of young people. Virtual worlds have the potential to become one additional environment, like school, home, and the playground, where youth can learn, play, and grow. The physical world is becoming interconnected with virtual worlds, and it is important for researchers to understand how this will affect children's development. Virtual worlds technologies provide a unique opportunity to allow youth to explore many types of content creation, including customizable avatars, media galleries, and virtual representations of personal spaces. This ability for youth to create content can be an important means by which to support and encourage adolescent identity development.
Mobilizing Communities to Implement Evidence‐Based Practices in Youth Violence Prevention: The State of the Art
Authors: Backer Thomas E. , Guerra Nancy G.
Published: January 2011

Community mobilization can increase the effective implementation of evidence‐based practices (EBPs) in youth violence prevention. These strategies bring together people and organizations in a community to try to solve or reduce a problem. They help communities address the challenges of identifying EBPs, disseminating them to local decision‐makers, and then implementing and sustaining them if they are successful. Science‐based systems for implementing EBPs such as PROSPER and Communities That Care can help to integrate this complex work in communities. Further insight about implementing EBPs in youth violence prevention is being developed through the CDC‐funded Academic Centers for Excellence in Youth Violence Prevention. Community mobilization approaches for seven of these programs are discussed, highlighting successful approaches and challenges encountered.
Selection of nest sites by wood mice Apodemus sylvaticus in a Mediterranean agro‐forest landscape
Authors: Rosalino Luís M. , Ferreira Dulce , Leitão Inês , Santos‐Reis Margarida
Published: January 2011

One of the most important structures for an individual's survival is a refuge, especially for species subject to significant predatory pressure or living in environments affected by severe climatic conditions. We studied how wood mice (Apodemus sylvaticus), inhabiting a Mediterranean environment, use nests and the factors that could be determining this use. Radio‐tracking of 16 mice allowed us to detect 24 diurnal nests, which were used with a high fidelity rate (1.75 nests/animal). Nest sites that had been identified using radio‐tracking were matched with 24 randomly selected non‐nest sites (located within an area defined by the sum of all individual home ranges), and all sites were characterized according to their macro‐ and micro‐habitat parameters. Using a generalized linear model, we tested three hypotheses: (1) a nest's use is influenced by its proximity to food patches; (2) the degree of sheltering provided by each site influences its use; and (3) nest use is constrained by a combination of food‐ and shelter‐related features. Females had higher nest fidelity than males, and the degree of sheltering provided by each site had a positive significant influence on its use. Nests offering higher protection (e.g., under thick vegetation), good drainage (e.g., sleep slopes), and lower human and predatory disturbance (far from orchards) were most often used. The proximity to food patches seemed to negatively influence nest use. Results indicate the need to preserve patches of natural dense vegetation near riparian habitats, which is in agreement with the focus of mammalian protection plans in Mediterranean agricultural landscapes. These patches are important areas for Apodemus sylvaticus, an acorn disperser species, which is preyed on by raptors and mammalian carnivores.
Les tumeurs testiculaires à cellules de Leydig: à propos de quatre cas et revue de la littérature
Authors: Tazi M. F. , Ahsaini M. , Khalouk A. , Fassi M. J. , Farih M. H.
Published: January 2011

Introduction

Les tumeurs testiculaires à cellules de Leydig (TTCL) sont rares, elles représentent entre 1 et 3 % de l’ensemble des tumeurs testiculaires, ce sont les plus fréquentes des tumeurs des cordons sexuels et du stroma. Ces tumeurs se développent le plus fréquemment (55 %) chez les sujets jeunes de 15 à 35 ans, mais elles peuvent se voir aussi chez les enfants lors de la première décennie (20 %) et chez les hommes après 50 ans (25 %). Le mode de révélation le plus fréquent chez l’adulte est la gynécomastie, par contre chez l’enfant, c’est la pseudopuberté précoce isosexuelle. Elles posent le problème de leur diagnostic biologique devant des formes non palpables et du choix de leur traitement chirurgical en raison de la difficulté diagnostique entre les formes bénignes et malignes.

Matériel et méthodes

Nous rapportons quatre présentations différentes de cette pathologie dont les paramètres étudiés seront l’âge, le mode de révélation, le profil hormonal, le type de traitement et le mode évolutif.

Résultats

L’âge moyen de nos patients était de 37 ans et demi. Le mode de révélation était deux fois sur quatre en rapport avec une grosse bourse unilatérale, une fois pour grosse bourse bilatérale, une fois en rapport avec une gynécomastie. Dans tous les cas, la testostérone était normale ou basse et l’estradiol normal ou élevé. Les quatre patients ont subi une orchidectomie associée à une énucléation controlatérale chez un seul des patients. L’évolution était favorable pour tous nos patients, avec un recul moyen de 15 mois.

Conclusion

Le but de cette revue est de présenter, sur la base de quatre observations cliniques différentes et de l’analyse de la littérature, les différents aspects cliniques, biologiques, radiologiques pathologiques et thérapeutiques des TTCL.
Direct nodal sampling by echoendoscopy in lung cancer: the clinician’s expectations
Authors: Schuhmann Maren , Eberhardt Ralf , Herth Felix J. F.
Published: January 2011

Background

Mediastinal lymph node staging for lung cancer remains one of the most important factors to determine patient outcome.

Methods

Noninvasive imaging techniques such as CT, MRI, PET and PET-CT provide some answers but no tissue diagnosis.

Results

The development of endo-oesophageal (EUS) and endobronchial ultrasound (EBUS) with fine-needle aspiration has provided the clinician with a tool to investigate the mediastinum and the adrenal gland with a safe, minimally invasive procedure that can be performed on an outpatient basis.

Conclusion

The aim of this article was to give radiologists an overview of the techniques of EUS and EBUS and their role in the staging of lung cancer patients.
Pflegestützpunkte und Nutzerorientierung – eine langfristige Organisationsentwicklungsaufgabe
Authors: Röber Michaela , Hämel Kerstin
Published: January 2011

Einleitung

Mit dem Pflegeweiterentwicklungsgesetz (2008) wurde ein Rechtsanspruch auf Pflegeberatung geschaffen. In der Mehrzahl der Bundesländer soll die Beratung, die von den Pflegekassen vorzuhalten ist, in Pflegestützpunkten stattfinden. Dort sollen mit Beteiligung der Kommunen Unterstützungsangebote im Bereich Hilfe und Pflege wohnort- und nutzernah gebündelt werden. In diesem Beitrag werden Implementierungsprobleme sowie Handlungsfelder für eine nutzerorientierte Ausrichtung diskutiert.
Interne und externe Patientenorientierung in der medizinischen Rehabilitation
Authors: Körner Mirjam , Ehrhardt Heike , Steger Anne-Kathrin
Published: January 2011

Einleitung

In der medizinischen Rehabilitation besteht die Notwendigkeit, aus dem bislang arztorientierten System ein patientenorientiertes System zu entwickeln. Es ist dabei nicht ausreichend die Bedürfnisse und Präferenzen der Patienten in den Behandler-Patient-Interaktionen (externe Patientenorientierung) zu berücksichtigen, sondern die gesamten Strukturen, Prozesse in der Klinik (interne Patientenorientierung) müssen konsequent an den Patientenanforderungen ausgerichtet werden.
Assessing incrementalism: Formative assumptions, contemporary realities
Authors: Pal Leslie A
Published: January 2011

Lindblom's 1959 article on incrementalism is one of the most cited works in social science.1 This article examines and probes five of the theory's basic, underlying assumptions in light of current empirical and theoretical approaches. The five assumptions are: (1) the limited nature of rationality and the weak powers of human cognition, (2) the emphasis on practical reason and applied knowledge, (3) partisan mutual adjustment conceived as interactions and conflicts among singular, distinct, and disconnected entities, (4) policy decisions made incrementally can be remediated and reversed, and (5) the United States political system is taken as the model for incremental politics. In our assessment, incrementalism holds up quite well with more recent thinking on public policy process with respect to the first and second assumptions. The third assumption has been confronted by new work on networks. The fourth has been challenged by theories on path dependency. The fifth assumption betrayed a national focus and strong value consensus – globalization and “culture wars” have rendered it untenable. The article therefore gives only qualified support for the continued relevance of incrementalism as a theory of the policy process.
Modulatory effect of fatty acids on fungicidal activity, respiratory burst and TNF-α and IL-6 production in J774 murine macrophages
Authors: Martins de Lima-Salgado Thais , Coccuzzo Sampaio Sandra , Fernanda Cury-Boaventura Maria , Curi Rui
Published: January 2011

The reported effects of different families of fatty acids (FA; SFA, MUFA, n-3 and n-6 PUFA) on human health and the importance of macrophage respiratory burst and cytokine release to immune defence led us to examine the influence of palmitic acid (PA), oleic acid (OA), linoleic acid, arachidonic acid, EPA and DHA on macrophage function. We determined fungicidal activity, reactive oxygen species (ROS) and cytokine production after the treatment of J774 cells with non-toxic concentrations of the FA. PA had a late and discrete stimulating effect on ROS production, which may be associated with the reduced fungicidal activity of the cells after treatment with this FA. OA presented a sustained stimulatory effect on ROS production and increased fungicidal activity of the cells, suggesting that enrichment of diets with OA may be beneficial for pathogen elimination. The effects of PUFA on ROS production were time- and dose-dependently regulated, with no evident differences between n-3 and n-6 PUFA. It was worth noting that most changes induced after stimulation of the cells with lipopolysaccharide were suppressed by the FA. The present results suggest that supplementation of the diet with specific FA, not classes of FA, might enable an improvement in host defence mechanisms or a reduction in adverse immunological reactions.
ZAI IMPROVES NUTRIENT AND WATER PRODUCTIVITY IN THE ETHIOPIAN HIGHLANDS
Authors: AMEDE TILAHUN , MENZA MESFIN , AWLACHEW SELESHI BEKELE
Published: January 2011

In the East African highlands, crop yields tend to increase with proximity of the farm plots to homesteads. Farmers identified soil erosion as the most detrimental cause of low crop yield in the outfields followed by soil compaction due to livestock trampling. The main objective of this study was to determine whether zai pits (i.e. small water harvesting pits) developed for dryland regions of the Sahel could increase crop yield and water productivity of degraded outfields in high rainfall areas, where mean annual rainfall exceeds 1300 mm but soil water infiltration is reduced by slope, low soil organic matter and hardpans. The pits were enlarged to resist strong runoff flows. The research was conducted over three years from 2004 to 2006. Potatoes and beans were used as test crops. Overall, compared to control plots, the zai pits, in combination with nitrogen (N) inputs, increased potato yields from 500% to 2000% (p ≤ 0.001). The pits contributed more to increased crop yield than N inputs. Similarly, bean yields from the zai pits were up to 250% higher. Crop water productivity was 300–700% higher with zai pits than with control plots. The income of farmers who used zai pits was up to 20-fold higher than the labour costs required to prepare them. Contrary to conventional wisdom, this study reveals that the major constraint of the outfields is not nutrient deficiency per se rather low soil water holding capacity, which hinders crop growth and efficient utilization of available nutrients.
INSTITUTIONAL IMPLICATIONS OF GOVERNANCE OF LOCAL COMMON POOL RESOURCES ON LIVESTOCK WATER PRODUCTIVITY IN ETHIOPIA
Authors: DENEKE TILAYE TEKLEWOLD , MAPEDZA EVERISTO , AMEDE TILAHUN
Published: January 2011

Improving water productivity depends on how local communal water and grazing resources are governed. This involves institutional and organizational issues. In the mixed farming systems of the Amhara Regional State, Ethiopia, non-participatory water users’ associations, neglect of traditional water rights, corruption, village power relations, inequitable allocation of irrigated land and free-grazing practice impact the governance of local common pool resources (CPR). Indigenous governance structures for CPR such as thekireare participatory and effective in terms of rule enforcement. Externally initiated governance structures lack acceptance by farmers and sufficient support from local government. In order to improve water productivity in the mixed farming systems, institutional deficiencies need attention and existing indigenous governance structures require recognition and support.
The role of urban agriculture in building resilient cities in developing countries
Authors: DE ZEEUW H. , VAN VEENHUIZEN R. , DUBBELING M.
Published: January 2011

The current paper briefly summarizes the available evidence regarding the potential of urban agriculture to respond to a number of key urban challenges and reviews the perspectives on urban agriculture applied by local and national authorities. The last section of the paper briefly presents the authors’ views on the development of urban agriculture as an integral part of sustainable city development.
Direct numerical simulation of heat transfer from the stagnation region of a heated cylinder affected by an impinging wake
Authors: WISSINK JAN G. , RODI WOLFGANG
Published: January 2011

The effect of an incoming wake on the flow around and heat transfer from the stagnation region of a circular cylinder was studied using direct numerical simulations (DNSs). Four simulations were carried out at a Reynolds number (based on free-stream velocity and cylinder diameterD) ofReD= 13200: one two-dimensional (baseline) simulation and three three-dimensional simulations. The three-dimensional simulations comprised a baseline simulation with a uniform incoming velocity field, a simulation in which realistic wake data – generated in a separate precursor DNS – were introduced at the inflow plane and, finally, a simulation in which the turbulent fluctuations were removed from the incoming wake in order to study the effect of the mean velocity deficit on the heat transfer in the stagnation region. In the simulation with realistic wake data, the incoming wake still exhibited the characteristic meandering behaviour of a near-wake. When approaching the regions immediately above and below the stagnation line of the cylinder, the vortical structures from the wake were found to be significantly stretched by the strongly accelerating wall-parallel (circumferential) flow into elongated vortex tubes that became increasingly aligned with the direction of flow. As the elongated streamwise vortical structures impinge on the stagnation region, on one side they transport cool fluid towards the heated cylinder, while on the other side hot fluid is transported away from the cylinder towards the free stream, thereby increasing the heat transfer. The DNS results are compared with various semi-empirical correlations for predicting the augmentation of heat transfer due to free-stream turbulence.