bluuebunny/crossref_metadata_2025 huggingface dataset:
Donepezil, an acetylcholinesterase inhibitor, attenuates nicotine self‐administration and reinstatement of nicotine seeking in rats
Authors: Kimmey Blake A. , Rupprecht Laura E. , Hayes Matthew R. , Schmidt Heath D.
Published: December 2012

Nicotine craving and cognitive impairments represent core symptoms of nicotine withdrawal and predict relapse in abstinent smokers. Current smoking cessation pharmacotherapies have limited efficacy in preventing relapse and maintaining abstinence during withdrawal. Donepezil is an acetylcholinesterase inhibitor that has been shown previously to improve cognition in healthy non–treatment‐seeking smokers. However, there are no studies examining the effects of donepezil on nicotine self‐administration and/or the reinstatement of nicotine‐seeking behavior in rodents. The present experiments were designed to determine the effects of acute donepezil administration on nicotine taking and the reinstatement of nicotine‐seeking behavior, an animal model of relapse in abstinent human smokers. Moreover, the effects of acute donepezil administration on sucrose self‐administration and sucrose seeking were also investigated in order to determine whether donepezil's effects generalized to other reinforced behaviors. Acute donepezil administration (1.0 or 3.0 mg/kg, i.p.) attenuated nicotine, but not sucrose self‐administration maintained on a fixed‐ratio 5 schedule of reinforcement. Donepezil administration also dose‐dependently attenuated the reinstatement of both nicotine‐ and sucrose‐seeking behaviors. Commonly reported adverse effects of donepezil treatment in humans are nausea and vomiting. However, at doses required to attenuate nicotine self‐administration in rodents, no effects of donepezil on nausea/malaise as measured by pica were observed. Collectively, these results indicate that increased extracellular acetylcholine levels are sufficient to attenuate nicotine taking and seeking in rats and that these effects are not due to adverse malaise symptoms such as nausea.
Creating change: building the capacity of the medical workforce in Aboriginal health
Authors: Paul David
Published: December 2012

Background

This paper provides an overview of the long‐term strategies that have been in place at the University of Western Australia, which aim to build the capacity and preparedness of the health‐care workforce in Aboriginal health. In 1996, the Centre for Aboriginal Medical and Dental Health was established within the Faculty of Medicine, Dentistry and Health Sciences to implement a comprehensive approach to Aboriginal health.

Methods

The initial focus was on developing recruitment and retention strategies that meaningfully address the significant under‐representation of Aboriginal and Torres Strait Islander people in the medical and broader health professions. At the same time, the Centre developed, implemented and evaluated a comprehensive vertically and horizontally integrated Aboriginal health curriculum initially in the Medicine course and subsequently in the Podiatry and Nursing courses within the faculty.

Results

The priority has been to ensure that all graduates will be better prepared to work effectively and safely with Aboriginal and Torres Strait Islander people and communities. Without effective alternative entry processes access to tertiary health courses and health careers would not have been an option for the majority of Aboriginal and Torres Strait Islander students and graduates.

Conclusion

This paper reflects on the partnerships, structures and approaches that have enabled the achievements to date and on the challenges that confront not only initial implementation but also sustaining the gains already made.
Comparative morphology of the tentorium and hypopharyngeal–premental sclerites in sporophagous and non‐sporophagous adult Aleocharinae (Coleoptera: Staphylinidae)
Authors: Weide Daniela , Thayer Margaret K. , Betz Oliver
Published: December 2012

We elucidate the configuration of the tentorium and the sclerites of the hypopharynx–prementum complex in selected spore‐ (pollen‐) and non‐spore‐feeding Aleocharinae (Staphylinidae) by presenting the first comparative 3D reconstructions of these structures for 19 staphylinoid beetle species (six outgroups, 13 Aleocharinae). General organization of the tentorium follows the groundplan previously proposed for adult Staphylinidae, although some taxa have reduced or lost the dorsal (all Aleocharinae studied, Agathidium mandibulare [Leiodidae]) or anterior (Omalium rivulare [Omaliinae], Anotylus sculpturatus [Oxytelinae]) tentorial arms. All species investigated have premental and hypopharyngeal sclerites that are partly homologizable across taxa. We clarified that Musculus praementopalpalis externus originates from the premental sclerite, resolving its unclear origin reported in our previous publications. Eight of 13 investigated Aleocharinae species are spore/pollen feeders, six obligatorily. Three of these six (Eumicrota, Gyrophaena fasciata, G. gentilis) have grinding pseudomolae and a fully developed hypopharyngeal suspensorium with posterior bridge and anterior elongations; the remaining three (Oxypoda, Pagla, Polylobus) lack pseudomolae and suspensorial bridge, but have the suspensorium elongated anteriorly. The dorsolateral side of the hypopharyngeal sclerite interacts with the pseudomola. Obligate sporophagy/pollinivory apparently arose at least three times in Aleocharinae, not always involving the pseudomola–hypopharynx grinding mechanism.
Coronary Arteriovenous Fistula in a Patient with Aortic Valve Regurgitation
Authors: Ganji Jhansi L. , Click Roger L. , Najib Mohammad Q. , Schaff Hartzell V. , Chaliki Hari P.
Published: December 2012

Mini‐Abstract

We present a case of a 25‐year‐old man with aortic regurgitation secondary to infective endocarditis. A preoperative transesophageal echocardiography demonstrated an abnormal aortic valve with possible vegetation or torn leaflet with severe aortic regurgitation, markedly dilated left coronary arteries, and a fistulous communication between the circumflex artery and the coronary sinus. The aortic valve was repaired and the coronary sinus arteriovenous fistula was ligated. At 1‐year follow‐up, there was no evidence of recurrent arteriovenous fistula or aortic regurgitation.
Relationship between Myocardial Performance Index and Severity of Coronary Artery Disease Assessed with SYNTAX Score in Stable Coronary Artery Disease
Authors: Şahin Durmuş Yıldıray , Gür Mustafa , Elbasan Zafer , Uysal Onur Kadir , Özaltun Betül , Şeker Taner , Özkan Buğra , Kalkan Gülhan Yüksel , Kıvrak Ali , Çaylı Murat
Published: December 2012

Background

The aim of the study was to investigate the relationship between severity of coronary artery disease (CAD) assessed with SYNTAX score (SS) and myocardial performance index (MPI) in stable CAD.

Methods

The study participants consisted of 106 consecutive patients (mean age: 57.6 ± 9.5 years) with angiographically proven obstructive stable CAD and 30 patients with nonobstructive CAD (control group) (mean age: 58.0 ± 7.6 years). The MPI was calculated by using pulsed‐wave Doppler before coronary angiography. Coronary angiography was performed in all patients. The SS was prospectively calculated in 106 obstructive CAD patients. Patients were partitioned into 3 groups based on SS. Frequencies of risk factors, biochemical and hematological data were recorded in all patients.

Results

The SS tertiles were defined as SSlow ≤ 8 (n = 35), SSmid ≤ 17 (n = 36), and SShigh > 17 (n = 35). The patients with SShigh group (mean MPI; 0,48 ± 0.06) based on SS had significantly higher MPI values compared with the SSmid (mean MPI; 0,44 ± 0.05), SSlow (mean MPI; 0.43 ± 0.06), and control (mean MPI; 0.41 ± 0.05) groups (P < 0.05 for all). The MPI levels of control group were also lower than compared with SSmid group (P = 0.006). The MPI value was significantly correlated with SS (r = 0.564, P < 0.001), diabetes (r = 0.355, P < 0.001), hypertension (r = 0.326, P < 0.001), and ejection fraction (EF) (r = −0.224, P = 0.018) in bivariate analysis. Multivariate regression analysis showed that MPI was independently associated with SS (β = 0.486, P < 0.001) and diabetes (β = 0.205, P = 0.028).

Conclusion

Although the normal EF, MPI value was impaired in proportion to the severity of CAD in patients with stable CAD.
The effect of one additional driver mutation on tumor progression
Authors: Reiter Johannes G. , Bozic Ivana , Allen Benjamin , Chatterjee Krishnendu , Nowak Martin A.
Published: December 2012

Tumor growth is caused by the acquisition of driver mutations, which enhance the net reproductive rate of cells. Driver mutations may increase cell division, reduce cell death, or allow cells to overcome density‐limiting effects. We study the dynamics of tumor growth as one additional driver mutation is acquired. Our models are based on two‐type branching processes that terminate in either tumor disappearance or tumor detection. In our first model, both cell types grow exponentially, with a faster rate for cells carrying the additional driver. We find that the additional driver mutation does not affect the survival probability of the lesion, but can substantially reduce the time to reach the detectable size if the lesion is slow growing. In our second model, cells lacking the additional driver cannot exceed a fixed carrying capacity, due to density limitations. In this case, the time to detection depends strongly on this carrying capacity. Our model provides a quantitative framework for studying tumor dynamics during different stages of progression. We observe that early, small lesions need additional drivers, while late stage metastases are only marginally affected by them. These results help to explain why additional driver mutations are typically not detected in fast‐growing metastases.
Analysing Electroacoustic Music: an Interactive Aural Approach
Authors: Clarke Michael
Published: December 2012

Electroacoustic music presents particular challenges to the analyst. Often the music is not notated, and where notation is used it may well take a different form and serve a different purpose to that of acoustic music. Furthermore, the sounds employed may not be traditionally musical, and pitch and rhythm may not be the most significant parameters in the musical argument. The concept of the note as the basic building block of a work may not be appropriate, since significant structural activity may take place at a lower level or because seamless extended transformations may be used. Transcribing such music can also prove problematic, whether using traditional Western musical notations or other approaches. So where might the analytical process begin, and how can its outcomes be communicated? This article examines these issues and presents a new interactive aural approach, in which software is used to engage directly with the sounds and to allow the reader to interact with the musical materials and the methods used to create them. The development of this approach is discussed in relation to three analyses of contrasting works by Jonathan Harvey, Denis Smalley and Pierre Boulez.
Introduction: crise, réactions politiques et creusement des inégalités dans l'Union européenne
Authors: LESCHKE Janine , JEPSEN Maria
Published: December 2012

Dans l'introduction à ce numéro spécial de la Revue internationale du Travail, les auteurs retracent les grandes phases de la crise économique dans l'Union européenne depuis 2008 et soulignent le rôle crucial des politiques sociales pour en atténuer les effets sur la population. Toutefois, et les auteurs l'illustrent avec les inégalités entre hommes et femmes, la crise et les réactions des gouvernements ont aussi aggravé les inégalités sur le marché du travail, au sein des pays et entre eux. En outre, les variations d'un pays à l'autre, quant au contenu et à la structure des mesures de relance et d'austérité, ont aussi accentué les divergences entre les pays de l'Union.
Rémunérations et inégalités de revenu dans l'Union européenne pendant la crise
Authors: de BEER Paul
Published: December 2012

Les auteurs examinent les effets de la crise économique sur l'emploi, les rémunérations, les inégalités et la pauvreté dans l'Union européenne entre 2008 et 2010, notamment dans cinq pays: Allemagne, Danemark, Espagne, Royaume‐Uni et Slovaquie. Après une présentation des études antérieures, ils constatent, à ce premier stade de la crise, un comportement contracyclique des salaires réels, à la différence de ce que l'on observait lors des précédentes récessions. S'agissant des inégalités et de la pauvreté, l'intensité et la direction de leur évolution varient considérablement. Toutefois, les inégalités pourraient s'aggraver en raison des effets régressifs des politiques d'austérité annoncées ou engagées.
Tracing the fate of EU “social policy”: Changes in political discourse from the “Lisbon Strategy” to “Europe 2020”
Authors: BARBIER Jean‐Claude
Published: December 2012

Analysing selected European Commission and Council documents, this article identifies the changes and enduring features of the EU social policy discourse and investigates their potential determinants. It divides this discourse into three periods: the first is associated with the “Lisbon Strategy”, the second with the reforms that followed (2005–09) and the third with “Europe 2020”. The most recent period has witnessed a radical marginalization and tokenization of social policy as compared with macroeconomic and financial concerns. At the same time, EU institutions have increasingly encroached upon national jurisdiction over social policy. These changes seem to be explained by reshuffling among important actors.
Introducción: crisis, políticas para afrontarla y desigualdad en la UE
Authors: LESCHKE Janine , JEPSEN Maria
Published: December 2012

Esta introducción presenta los demás artículos del número monográfico y analiza las etapas de la crisis económica en la Unión Europea desde 2008, destacando la importancia de la política social para mitigar sus efectos iniciales en los europeos. Tanto la crisis como las medidas gubernamentales para afrontarla han exacerbado la desigualdad laboral dentro de cada país, como ponen de manifiesto el aumento desproporcionado del desempleo juvenil y los datos sobre género aportados por las autoras. Las divergencias en cuanto a estructura y contenido de los planes de estímulo y de austeridad nacionales también parecen explicar el aumento de las diferencias entre países dentro de la UE.
Environmental correlates of anuran beta diversity in the Brazilian Cerrado
Authors: Valdujo Paula H. , Carnaval Ana Carolina O. Q. , Graham Catherine H.
Published: December 2012

Evolutionary processes are known to influence contemporary patterns of biological diversity, yet disentangling the effects of current and historical drivers of biodiversity patterns remain challenging. We use spatial analyses of community dissimilarity to generate hypotheses about the current and historical processes underlying patterns of beta diversity in anuran species in the Brazilian Cerrado. Specifically, we use a generalized dissimilarity modeling (GDM) approach to model compositional dissimilarity of anuran species and endemics as a function of geographic separation and local (within‐Cerrado) environmental conditions. To gain insight about potential historical processes, we incorporate information from biomes adjacent to the Cerrado to investigate whether environmental conditions in neighboring areas can help explain patterns of beta diversity within the Cerrado. Patterns of anuran beta diversity of both endemics and all species in the Cerrado appear to be strongly influenced by local environmental gradients, with elevation as one of the most important variables in all models. However, in models using endemic species only, environmental conditions of adjacent biomes were related to beta‐diversity patterns, and more strongly so, than to total species models. These results suggest that phylogenetic niche conservatism within species groups that invaded the Cerrado from adjacent biomes may cause these species to be restricted to environmental conditions within the Cerrado that are most similar to the conditions in the adjacent biome where they originated. Time‐calibrated phylogenies of Cerrado endemics and studies of ancestral and current ranges of Cerrado species are needed to test this hypothesis.
To evaluate the comparative status of oral health practices, oral hygiene and periodontal status amongst visually impaired and sighted students
Authors: Jain Ashish , Gupta Jyoti , Aggarwal Vyom , Goyal Chinu
Published: December 2012

The aim of this study was to evaluate the comparative status of oral health practices, oral hygiene, and periodontal status amongst visually impaired and sighted students. In this study, 142 visually impaired children from a blind school in the age group of 6–18 years were enrolled with a similar number of age and sex matched sighted students studying in different schools of Chandigarh. The outcome variables were oral hygiene practices, oral hygiene status, and periodontal status. The visually impaired had been found to have better oral hygiene practices, a nonsignificant difference of oral hygiene scores but a significantly high value for bleeding scores as compared to sighted students. Age wise comparisons showed that bleeding scores were highly significant in 9–11 years and 12–14 years age group as compared to 6–8 years and 15–18 years age group. It could be related that the increased prevalence of bleeding sites despite of better oral hygiene practices in visually impaired group might be the result of their handicap to visualize plaque.
Effect of pregnancy on gingival inflammation in systemically healthy women: a systematic review
Authors: Figuero Elena , Carrillo‐de‐Albornoz Ana , Martín Conchita , Tobías Aurelio , Herrera David
Published: December 2012

Aim

To obtain an overall quantitative estimate of the association between pregnancy and gingival inflammation.

Material and Methods

Medline and EMBASE databases were searched through August 2011. Prospective cohort or cross‐sectional studies assessing the effect of pregnancy on gingival inflammation evaluated by the gingival index (GI) and/or bleeding on probing were included. Meta‐analyses were performed if possible.

Results

Forty‐four articles representing 33 studies (14 cohort and 19 cross‐sectional) were included. Meta‐analyses, performed whenever possible, revealed (1) a significantly lower GI in pregnant women in the first term compared with those in their second or third term of pregnancy; (2) a lower mean GI score in post‐partum women compared with women in their second [WMD = 0.143; 95% CI (0.031; 0.255); p = 0.012] or third term [WMD = 0.256; 95% CI (0.151; 0.360); p < 0.001] of pregnancy, when considering cohort studies; (3) Non‐pregnant women had lower mean GI values than women in their second or third term of pregnancy. Small changes in plaque levels were reported.

Conclusion

Despite the limited number of studies included in the meta‐analyses, the present systematic review confirms the existence of a significant increase in GI throughout pregnancy and between pregnant versus post‐partum or non‐pregnant women, without a concomitant increase in plaque levels.
Rural Livelihoods inSouthAfrica: Complexity, Vulnerability and Differentiation
Authors: Neves David , du Toit Andries
Published: December 2012

The livelihoods ofSouthAfrica's ruralAfrican poor have long been characterized by diverse activities, and intertwined with urban opportunities. This paper examines the interlinked nature of land, employment and rural livelihoods within contemporarySouthAfrica, in order to examine aspects of how the rural poor survive. Drawing on a body of livelihood and poverty‐oriented enquiry, several vignettes from South Africa's former ‘homeland’ communal areas are presented and discussed. Contemporary rural livelihoods are not only located in migratory networks and diverse livelihood activities, they are considered here as constituted in terms of four broad domains. First, they are forged within various land‐based and agrarian activities. Second, they are often supported by small‐scale, informal economic activities, both farm and non‐farm. Third, they are frequently shaped bySouthAfrica's comparatively well‐developed system of state cash transfers and, fourth, they are patterned by culturally inscribed patterns of mutuality and social reciprocity. The complexity and vulnerability that typically characterize rural lives are examined in terms of these four domains, along with constellations of social differentiation with which they are intertwined.
Commercial Agriculture inSouthAfrica since 1994: ‘Natural, Simply Capitalism’
Authors: Bernstein Henry
Published: December 2012

The paper provides a survey of commercial agriculture inSouthAfrica since 1994. It emphasizes, first, how effectively ‘organized agriculture’ positioned itself for the new dispensation, with the help of the last apartheid government, and, second, the importance of the removal of limits on the international mobility ofSouthAfrican capital and commodities imposed on the apartheid regime. The lacunae and ambiguities of theAfricanNationalCongress concerning land and agricultural policy during the political transition of 1990–4 and since then in government are also important here. The paper considers ‘transformation(s)’ with respect to farm labour, regulating agribusiness, and land reform, black farming, andBlackEconomicEmpowerment (BEE, specificallyAgriBEE). It concludes that the course ofSouthAfrican agriculture and agricultural policy since 1994 has done little, if anything, to ‘transform’ the circumstances of the dispossessed – rural and urban classes of labour – whose crises of social reproduction remain grounded in the inheritances of racialized inequality.
Relationship between gagging severity and its management in dentistry
Authors: Saita N. , Fukuda K. , Koukita Y. , Ichinohe T. , Yamashita S.
Published: December 2012

The purpose of this study was to investigate how grading according to our new gagging reflex index correlated with patient background and subsequent management. After obtaining institutional approval and informed consent, 110 patients with a gagging problem were enrolled. The patients completed the State–Trait Anxiety Inventory (STAI), the Dental Anxiety Scale (DAS), and a health questionnaire at initial consultation. On the second visit, an intra‐oral examination was carried out and the severity of gag reflex determined according to our new, 5‐level Classification of Gagging Problem (CGP) index: normal gagging but not desensitised (G1 = score 1); mild gagging (G2 = score 2); moderate gagging (G3 = score 3); severe gagging (G4 = score 4); and very severe gagging (G5 = score 5). No difference was found in grade based on age or STAI or DAS scores. The CGP score in male patients was significantly higher than that in female. The management classification method and degree of desensitisation were investigated retrospectively in each patient at 3 months and 1 year after initial consultation. The higher the CGP grade, the more often intravenous sedation or general anaesthesia was required due to difficultly in desensitisation. The present results suggest that determining whether it is possible to examine the molar area without inducing the gag reflex offers the key to deciding the treatment strategy.
Associations between single‐nucleotide polymorphisms of the VEGF gene and long‐term prognosis of oral squamous cell carcinoma
Authors: Kämmerer P. W. , Koch F. P. , Schiegnitz E. , Kumar V. V. , Berres M. , Toyoshima T. , Al‐Nawas B. , Brieger J.
Published: December 2012

Introduction

Functional polymorphisms (SNPs) of the vascular endothelial growth factor (VEGF) are associated with the incidence of oral squamous cell carcinoma (OSCC). An impact of VEGF‐SNPs on prognosis of OSCC patients seems possible. Therefore, correlations between prognostic parameters of OSCC patients and five VEGF‐SNPs were determined.

Materials and Methods

In a retrospective long‐term study, in 113 OSCC patients that underwent curative resections, five VEGF‐SNPs (−1154 G/A, +405 G/C, +936 C/T, −2578 C/A, and −460 C/T) were analyzed. Associations between SNPs and prognosis (incidence of local recurrent disease, second cancer, metastases, death, total disease‐free survival) were examined.

Results

After a mean follow‐up time of 57.6 months, 32 patients had local recurrences; 15 patients had second cancer, 15 patients metastases, and 23 patients died. The mean disease‐free survival was 43.1 months. A significant increased incidence of OSCC in smokers with the VEGF −2578 A/C and −460 C/T SNP was seen (each P < 0.0001). In univariate analysis, patients with advanced OSCCs (T > 2 or N > 0) together with the −1154 A/A allele had a significant worse survival and a worse disease‐free survival (both P < 0.04). The same was seen for the +405 G/G SNP (both P = 0.002). In multivariate analysis, only the negative influence of the +405 G/G SNP on survival in advanced OSCCs (T > 2) could be confirmed (P = 0.002).

Discussion

Possible reciprocal interactions between smoking and VEGF‐SNP function were observed. Multivariate analysis confirmed the VEGF +405 G/G genotype to be associated with poor survival in advanced OSCCs; a further use of this haplotype as biomarker has to be discussed.
The Effect of Pregnancy Intention on Maternal Prenatal Behaviours and Parent and Child Health: Results of an Irish Cohort Study
Authors: McCrory Cathal , McNally Sinead
Published: December 2012

Background

Unintended pregnancy is associated with increased risk for adverse neonatal and early childhood outcomes spanning an array of indicators, but it remains unclear whether these risks hold independent of other biological, social and environmental risk factors.

Methods

This study uses data from the first wave of the ‘Growing Up in Ireland Study’, a large nationally representative cohort study of more than 11 000 infants, to examine the risk factors associated with unintended pregnancy. Adopting a staged approach to the analysis, the study investigates whether pregnancy intention influences maternal health behaviours during pregnancy independent of background characteristics, and whether pregnancy intention carries any additional risk for adverse infant and maternal health outcomes when we adjust for background characteristics and prenatal behaviours.

Results

The study confirmed that sociodemographic factors are strongly associated with unintended pregnancy and that unintended pregnancy is associated with a range of health compromising behaviours that are known to be harmful to the developing fetus. While there was little evidence to suggest that pregnancy intention was associated with adverse neonatal outcomes or developmental delay independent of other covariates, there was strong evidence that intention status had a bearing on the mother's psychosocial health. Unintended pregnancy was associated with increased risk of depression (risk ratio 1.36 [95% confidence interval 1.19, 1.54]), and higher parenting stress (risk ratio 1.27 [95% confidence interval 1.16, 1.38]).

Conclusions

Ascertaining the mother's pregnancy intention during the first antenatal visit may represent a means for monitoring those at greatest risk for adverse mother and child outcomes.
Estimating elasticities of demand and willingness to pay for clean drinking water: empirical evidence from a household level survey in northern Pakistan
Authors: Khan Himayatullah
Published: December 2012

This study estimates income and price elasticities of demand for improved drinking water quality in Peshawar, Pakistan. The estimates indicate that improved water can be described as a necessity but normal and an ordinary and price elastic service. Confidence intervals show however that the classification as a necessity is statistically significant. Income elasticities of willingness to pay for drinking water are estimated. The study finds that income and willingness to pay vary directly and significantly. The elasticity estimates, in general, are greater than zero, but less than unity. The study concludes that improvements in drinking water are more beneficial to low‐income groups than for high‐income groups.
Impact of changed cropping practices on weed occurrence in spring cereals in Finland – a comparison of surveys in 1997–1999 and 2007–2009
Authors: SALONEN J , HYVÖNEN T , KASEVA J , JALLI H
Published: December 2012

Salonen J, Hyvönen T, Kaseva J & Jalli H (2012). Impact of changed cropping practices on weed occurrence in spring cereals in Finland – a comparison of surveys in 1997–1999 and 2007–2009. Weed Research.

During recent decades, arable cropping has been intensified to increase production, but has also been constrained by agri‐environment schemes. Weed populations respond to such changes, thus indicating trends in cropping practices. In Finland, repeated monitoring of the weed flora aims to record and understand the response of weed populations to changing cultural conditions. Two recent surveys of the weed flora in Finnish spring cereal fields, conducted in 1997–1999 and 2007–2009, were evaluated to assess the effect of known changes in tillage practices and herbicide use on weed occurrence. The same 382 fields were assessed during both decades. In conventional cropping, the total abundance of weeds has remained at about the same level as recorded in the late 1990s. Overwintering weed species like Galium spurium, Lamium spp., Lapsana communis and Poa annua have become more frequent, indicating a trend towards reduced primary tillage. Increased use of glyphosate has in turn led to a decline in Elymus repens, particularly in non‐ploughed fields. Substantially increased total biomass of weeds was associated with organic cropping, due to lack of direct weed control methods and inadequate crop competition. The opposite trend was apparent in the fields, which had returned from organic farming back to conventional cropping. The results suggest that more decisive IPM strategies are required, both in organic cropping to stop the increasing weed biomass and in conventional cropping to reduce current reliance on herbicides.
Factors Affecting Hydraulically Fractured Well Performance in the Marcellus Shale Gas Reservoirs
Authors: Osholake Tunde , Yilin Wang John , Ertekin Turgay
Published: December 2012

Development of shale gas reservoirs has become an integral part of the North American gas supply. The Marcellus shale reservoir contains large untapped natural gas resources and its proximity to high demand markets along the East Coast of the United State makes it an attractive target for energy development. The economic viability of such unconventional gas development hinges on the effective stimulation of extremely low permeability reservoir rocks. Horizontal wells with multistage hydraulic fracturing technique are the stimulation method of choice and have been successful in shale gas reservoirs. However, the fundamental science and engineering of the process are yet to be fully understood and hence the protocol that needs to be followed in the stimulation process needs to be optimized. There are several factors affecting the hydraulic fracture treatment and the postfracture gas production in shale gas reservoirs. In this paper, we used numerical reservoir simulation techniques and quantified the effect of the following pertinent factors: multiphase flow, proppant crushing, proppant diagenesis, reservoir compaction, and operating conditions on the performance of the designed multistage hydraulic fracturing process. The knowledge generated in this study is expected to enable engineers to better design fracture treatments and operators to better manage the wells in the Marcellus shale gas reservoir.
Hydromagnetic Fluid Flow and Heat Transfer at a Stretching Sheet With Fluid-Particle Suspension and Variable Fluid Properties
Authors: Vajravelu K. , Prasad K. V. , Datti P. S.
Published: December 2012

In this paper, we investigate the influence of temperature-dependent fluid properties on the flow and heat transfer characteristics of an electrically conducting dusty fluid over a stretching sheet. Temperature-dependent fluid properties are assumed to vary as a function of the temperature. The governing coupled nonlinear partial differential equations along with the appropriate boundary conditions are transformed into coupled, nonlinear ordinary differential equations by a similarity transformation. The resultant coupled highly nonlinear ordinary differential equations are solved numerically by a second order implicit finite difference scheme known as the Keller–Box method. The numerical solutions are compared with the approximate analytical solutions, obtained by a perturbation technique. The analysis reveals that even in the presence of variable fluid properties the transverse velocity of the fluid is to decrease with an increase in the fluid-particle interaction parameter. This observation holds even in the presence of magnetic field. Furthermore, the effects of the physical parameters on the fluid velocity, the velocity of the dust particle, the density of the dust particle, the fluid temperature, the dust-phase temperature, the skin friction, and the wall-temperature gradient are assessed through tables and graphs.
Forecasting the Time Evolution of the Oil Price During Months of Negative Inflation Rate
Authors: Gori Fabio
Published: December 2012

Mass conservation equation is employed to study the time evolution of the mass of oil in a reservoir, according to the actual mass flow rate of extraction. It is also possible to define the critical mass flow rate of extraction, which is the value exhausting the reservoir in an infinite time. The evolution with time of the price of the resources extracted and sold to the market is investigated in case of no-accumulation and no-depletion of the resources, i.e., when the resources are extracted and sold to the market at the same mass flow rate. The total energy conservation equation is transformed into a money or capital per time conservation equation, which allows to study the price evolution with time, which is dependent on the following parameters. The price evolution with time of the extracted resource is dependent on the parameter PIFE, “Price-Increase Factor of Extracted resource,” which is the difference between the basic interest rate of the capital, e.g., the inflation rate, and the mass flow rate of extraction. The price evolution with time of the sold resource is dependent on the parameter PIFS, “Price-Increase Factor of Sold resource,” which is the difference between the interest rate of the capital, e.g., discount or prime rate, and the mass flow rate of extraction. The parameter CIPS, “Critical Initial Price of Sold resource,” depends on the initial price of the extracted resource, on the interest rate of nonextracted resource, and on the difference between PIFS and PIFE. The parameter CIPES, “Critical Initial Price Extreme of Sold resource,” depends on the initial price of the extracted resource, on the interest rate of nonextracted resource, and PIFS. The time evolution of the oil price during the 8 months of 2009, when the inflation rate was negative, and following the economic crisis of 2008, is investigated introducing a new category of cases, i.e., the negative inflation rate one. The paper presents and discusses the results of the forecasting for different values of the interest rate of the capital, i.e., prime and discount rate, with the conclusion that the present theory can forecast the evolution of the oil price with a reasonable confidence using the prime and the discount rates as extreme limits.
Numerical Modeling of the Effects of Disproportionate Permeability Reduction Water-Shutoff Treatments on Water Coning
Authors: Bekbauov Bakhbergen E. , Kaltayev Aidarkhan , Wojtanowicz Andrew K. , Panfilov Mikhail
Published: December 2012

In the present paper, we analyze numerically the disproportionate permeability reduction (DPR) water-shutoff (WSO) treatments in oil production well, i.e., the ability to reduce relative permeability (RP) to water more than to oil. The technique consists of bullhead injection of polymer solutions (gelant) into the near-wellbore formation without zone isolation. By assuming the low dissolution of polymer in oil and the low mobility of the gel in porous medium, we reduced the compositional model of the process to a simple two-phase model, with RP and capillary pressure (PC) dependent on the water and gel saturation. We proposed the extension of the LET correlations used to calculate RP and PC for the case of three phases (oil–water–gel). The problem is divided into two stages: the polymer injection and the post-treatment production. Both of these processes are described by the same formal mathematical model, which results from incompressible two-phase flow equations formulated in terms of normalized saturation and global pressure. The thermal effects caused by the injection of a relatively cold aqueous solution are taken into account. The numerical solution shows favorable results for the DPR WSO treatments. Other techniques, such as the creation of impermeable barrier and downhole water sink (DWS) technology, are also tested in order to check the validity of the developed numerical model with experimental data.
A Novel Combined Particle Swarm Optimization and Genetic Algorithm MPPT Control Method for Multiple Photovoltaic Arrays at Partial Shading
Authors: Liu Liqun , Liu Chunxia
Published: December 2012

The output characteristics of multiple photovoltaic (PV) arrays at partial shading are characterized by multiple steps and peaks. This makes that the maximum power point tracking (MPPT) of a large scale PV system becomes a difficult task. The conventional MPPT control method was unable to track the maximum power point (MPP) under random partial shading conditions, making the output efficiency of the PV system is low. To overcome this difficulty, in this paper, an improved MPPT control method with better performance based on the genetic algorithm (GA) and adaptive particle swarm optimization (APSO) algorithm is proposed to solve the random partial shading problem. The proposed genetic algorithm adaptive particle swarm optimization (GAAPSO) method conveniently can be used in the real-time MPPT control strategy for large scale PV system, and the implementation of the collect circuit is easy to gain the global peak of multiple PV arrays, thereby resulting in lower cost, higher overall efficiency. The proposed GAAPSO method has been experimentally validated by using several illustrative examples. Simulations and experimental results demonstrate that the GAAPSO method provides effective, fast, and perfect tracking.
Expression of RORγt Marks a Pathogenic Regulatory T Cell Subset in Human Colon Cancer
Authors: Blatner Nichole R. , Mulcahy Mary F. , Dennis Kristen L. , Scholtens Denise , Bentrem David J. , Phillips Joseph D. , Ham Soo , Sandall Barry P. , Khan Mohammad W. , Mahvi David M. , Halverson Amy L. , Stryker Steven J. , Boller Anne-Marie , Singal Ashima , Sneed Rebekka K. , Sarraj Bara , Ansari Mohammed Javeed , Oft Martin , Iwakura Yoichiro , Zhou Liang , Bonertz Andreas , Beckhove Philipp , Gounari Fotini , Khazaie Khashayarsha
Published: December 2012

T
regs
that expand in human colon cancer have proinflammatory properties and contribute to tumor progression.
Dantrolene Enhances Antisense-Mediated Exon Skipping in Human and Mouse Models of Duchenne Muscular Dystrophy
Authors: Kendall Genevieve C. , Mokhonova Ekaterina I. , Moran Miriana , Sejbuk Natalia E. , Wang Derek W. , Silva Oscar , Wang Richard T. , Martinez Leonel , Lu Qi L. , Damoiseaux Robert , Spencer Melissa J. , Nelson Stanley F. , Miceli M. Carrie
Published: December 2012

The ryanodine receptor antagonist dantrolene facilitates exon skipping of dystrophin for treatment of Duchenne muscular dystrophy.
Warranted Wiretapping: Listening in on Cancer’s Conversations
Authors: Baker Aaron B.
Published: December 2012

A new type of microfluidic chip allows monitoring of microvesicles to aid in detecting and treating brain cancer.
Remembering the Variants in Alzheimer’s Disease
Authors: Bettegowda Chetan
Published: December 2012

Individuals with a rare variant of
TREM2
, which codes for an immune cell–related receptor, are more likely to develop Alzheimer’s disease.
Simultaneous bilateral elbow dislocation with bilateral medial epicondyle fractures in a 13-year-old female gymnast with hyperlaxity
Authors: Bauer Stefan , Dunne Ben , Whitewood Colin
Published: December 2012

Bilateral simultaneous elbow dislocations are extremely rare and have only been described in 12 cases. In the paediatric population unilateral elbow dislocations are rare with 3–6% of all elbow injuries and there are only few studies describing this injury exclusively in children. There is only one case report of a paediatric patient who sustained a simultaneous bilateral elbow dislocation with medial epicondyle fractures. We present a second paediatric case of simultaneous bilateral elbow dislocation with associated displaced bilateral medial epicondyle fractures in a gymnast with joint hyperlaxity (3 of 5 Wynne-Davies criteria) treated with closed reduction and short-term immobilisation (3 weeks). The patient returned to full trampoline gymnastics between 4 and 5 months postinjury and made an uneventful recovery.
SUPERSYMMETRIC UNIFICATION AND R SYMMETRIES
Authors: CHEN MU-CHUN , FALLBACHER MAXIMILIAN , RATZ MICHAEL
Published: December 2012

We review the role of R symmetries in models of supersymmetric unification in four and more dimensions, and in string theory. We show that, if one demands anomaly freedom and fermion masses, only R symmetries can forbid the supersymmetric Higgs mass term μ. We then review the proof that R symmetries are not available in conventional grand unified theories (GUTs) and argue that this prevents natural solutions to the doublet–triplet splitting problem in four dimensions. On the other hand, higher-dimensional GUTs do not suffer from this problem. We briefly comment on an explicit string-derived model in which the μ and dimension-5 proton decay problems are solved simultaneously by an order four discrete R symmetry. We also comment on the higher-dimensional origin of this symmetry.
EVALUATION OF RAPID PROTOTYPING SOLUTIONS FOR A 802.16D FREQUENCY OFFSET ESTIMATION SCHEME
Authors: GONZÁLEZ-BAYÓN JAVIER , FERNÁNDEZ-HERRERO ANGEL , CARRERAS CARLOS
Published: December 2012

Synchronization of the carrier frequency offset (CFO) is a critical task in orthogonal frequency division multiplexing systems. Imperfect estimation of the CFO causes inter-carrier interference (ICI) that severely degrades the performance of the communications system. Although this is a well studied subject at the algorithmic level, more research is needed when considering implementations in real hardware. Translation of an algorithmic specification to a hardware language is a time consuming task for the designer. This task is more difficult when the target technology offers limited resources, as in the case of field programmable gate arrays (FPGAs). Some rapid prototyping tools, as System Generator from Xilinx or Synplify DSP from Synopsys Synplicity, are available for the designer to facilitate this task. However, their performance has not been evaluated in the literature. Therefore, the goal of this paper is to present an illustrating example of an implementation methodology using these tools and to evaluate their performance when considering a real design. In particular, several FPGA implementations of a frequency synchronization scheme for the 802.16d (fixed WiMAX) standard using these rapid prototyping tools are studied and evaluated. The results from the different solutions are analyzed and compared to draw conclusions about their advantages and drawbacks.
FOLDING OF A TYPE OF DEPLOYABLE ORIGAMI STRUCTURES
Authors: CHEN YAO , FENG JIAN
Published: December 2012

Some types of rigid origami possess specific geometric properties. They have a single degree of freedom, and can experience large configuration changes without cut or being stretched. This study presents a numerical analysis and finite element simulation on the folding behavior of deployable origami structures. Equivalent pin-jointed structures were established, and a Jacobian matrix was formed to constrain the internal mechanisms in each rigid plane. A nonlinear iterative algorithm was formulated for predicting the folding behavior. The augmented compatibility matrix was updated at each step for correcting the incompatible strains. Subsequently, finite element simulations on the deployable origami structures were carried out. Specifically, two types of generalized deployable origami structures combined by basic parts were studied, with some key parameters considered. It is concluded that, compared with the theoretical values, both the solutions obtained by the nonlinear algorithm and finite element analysis are in good agreement, the proposed method can well predict the folding behavior of the origami structures, and the error of the numerical results increases with the increase of the primary angle.
COMMUNICATION SUPPORT FOR MOBILE COLLABORATIVE WORK: AN EXPERIMENTAL STUDY
Authors: MESSEGUER ROC , MEDINA ESUNLY , OCHOA SERGIO F. , PINO JOSÉ A. , NEYEM ANDRES , NAVARRO LEANDRO , ROYO DOLORS
Published: December 2012

Advances in mobile computing and wireless communication are easing the evolution from traditional nomadic work to computer-mediated mobile collaborative work. Technology allows efficient and effective interaction among mobile users and also provides access to shared resources available to them. However, the features and capabilities of the communication infrastructure supporting these activities influence the type of coordination and collaboration employed by mobile collaborative applications in real work scenarios. Developers of these applications are typically unaware of the constraints the communication infrastructure imposes on mobile collaborative systems, because they are not easy to foresee. That leads to a high probability of communication problems in otherwise fully functional mobile collaborative support applications. This paper presents an experimental study with real devices and networks on a realistic physical environment that shows how ad hoc networks can effectively support mobile collaborative work and the practical limitations. The paper analyzes several networking issues and determines how they influence mobile collaborative work in various interaction scenarios. The paper also presents the lessons learned in the study and provides recommendations to deal with some networking issues related to real-world ad hoc networks.
COOPERATIVE RECONFIGURATION OF USER INTERFACE MODELS FOR LEARNING CRYPTOGRAPHIC PROTOCOLS
Authors: WEYERS BENJAMIN , LUTHER WOLFRAM , BALOIAN NELSON
Published: December 2012

Cooperative work in learning environments has been shown to be a successful extension to traditional learning systems due to the great impact of cooperation on students' motivation and learning success. A recent evaluation study has confirmed our hypothesis that students who constructed their roles in a cryptographic protocol cooperatively as sequence of actions in a user interface were faster in finding a correct solution than students who worked on their own. Here, students of a cooperation group modeled a user interface collaboratively for simulation of a cryptographic protocol using interactive modeling tools on a shared touch screen. In this paper, we describe an extended approach to cooperative construction of cryptographic protocols. Using a formal language for modeling and reconfiguring user interfaces, students describe a protocol step-by-step, modeling subsequent situations and thereby actions of the protocol. The system automatically generates a colored Petri net, which is matched against an existing action logic specifying the protocol, thus allowing formal validation of the construction process. The formal approach to modeling of user interfaces covers a much broader field than a simple cryptographic protocol simulation. Still, this paper seeks at investigating the use of such a formal modeling approach in the context of cooperative learning of cryptographic protocols and to develop a basis for more complex learning scenarios.