bluuebunny/crossref_metadata_2025 huggingface dataset:
Mobile data offloading in metropolitan area networks
Authors: Han Bo , Hui Pan , Srinivasan Aravind
Published: February 2011

Cellular networks, especially 3G networks, are currently overloaded with mobile data traffic. It is thus imperative to develop novel communication architectures and protocols for this problem. In this paper, we propose to exploit the delay-tolerant nature of non-realtime applications to offload mobile data traffic through opportunistic communications and WiFi networks. We argue that it is necessary for cellular network operators, WiFi service providers, and end-users to cooperate to make the offloading more effective. We also present several preliminary experiment results about the work we have been conducting, which show that it is promising to offload mobile data traffic in metropolitan area networks.
Automatic and efficient simulation of operation contracts
Authors: Krieger Matthias P. , Knapp Alexander , Wolff Burkhart
Published: February 2011

Operation contracts consisting of pre- and postconditions are a well-known means of specifying operations. In this paper we deal with the problem of operation contract simulation, i.e., determining operation results satisfying the postconditions based on input data supplied by the user; simulating operation contracts is an important technique for requirements validation and prototyping. Current approaches to operation contract simulation exhibit poor performance for large sets of input data or require additional guidance from the user. We show how these problems can be alleviated and describe an efficient as well as fully automatic approach. It is implemented in our tool OCLexec that generates from UML/OCL operation contracts corresponding Java implementations which call a constraint solver at runtime. The generated code can serve as a prototype. A case study demonstrates that our approach can handle problem instances of considerable size.
Code clones in feature-oriented software product lines
Authors: Schulze Sandro , Apel Sven , Kästner Christian
Published: February 2011

Some limitations of object-oriented mechanisms are known to cause code clones (e.g., extension using inheritance). Novel programming paradigms such as feature-oriented programming (FOP) aim at alleviating these limitations. However, it is an open issue whether FOP is really able to avoid code clones or whether it even facilitates (FOP-related) clones. To address this issue, we conduct an empirical analysis on ten feature-oriented software product lines with respect to code cloning. We found that there is a considerable number of clones in feature-oriented software product lines and that a large fraction of these clones is FOP-related (i.e., caused by limitations of feature-oriented mechanisms). Based on our results, we initiate a discussion on the reasons for FOP-related clones and on how to cope with them. We show by means of examples how such clones can be removed by applying refactorings.
Administering a Gross Anatomy Exam Using Mobile Technology
Authors: Jalali Alireza , Trottier Daniel , Tremblay Mariane , Hincke Maxwell
Published: February 2011

In less than a year since its debut the popularity of the iPad has not waned. In fact mobile devices are predicted to replace traditional PCs. At the Faculty of Medicine of the University of Ottawa, instructors were certain that incorporating mobile computing into the examination environment would benefit not only the university, but students as well. Read more about their experience in moving from paper to paperless exams to evaluate second year medical students.
A disintegrin and metalloprotease 10 activity sheds the ectodomain of the amyloid precursor-like protein 2 and regulates protein expression in proximal tubule cells
Authors: Cong Rong , Li Yuanli , Biemesderfer Daniel
Published: February 2011

A disintegrin and metalloprotease 10 (ADAM10) is a zinc protease that mediates ectodomain shedding of numerous receptors including Notch and members of the amyloid precursor protein family (APP, APLP1, and APLP2). Ectodomain shedding frequently activates a process called regulated intramembrane proteolysis (RIP) that links cellular events with gene regulation. To characterize ADAM10 in kidney and in opossum kidney proximal tubule (OKP) cells, we performed indirect immunofluorescence microscopy and immunoblotting of renal membrane fractions using specific antibodies. These studies show that ADAM10 and APLP2 are coexpressed in the proximal tubule and in OKP cells. To study the role of ADAM10 activity in the proximal tubule, we stably overexpressed wild-type ADAM10 or an inactive mutant ADAM10 in OKP cells. We found a direct correlation between the amount of active ADAM10 expressed and 1) the amount of APLP2 ectodomain shed into the culture supernatant and 2) the amount of Na+/H+ exchanger 3 (NHE3) and megalin mRNA and protein expressed compared with control proteins. To establish a link between ADAM10-mediated shedding of APLP2 and the effect on NHE3 and megalin mRNA expression we performed RNA interference experiments using APLP2-specific short hairpin RNA (shRNA) in OKP cells. Cells expressing the APLP2 shRNA showed >80% knock down of APLP2 protein and mRNA as well as 60–70% reduction in NHE3 protein and mRNA. Levels of megalin and Na-K-ATPase protein and mRNA were not changed. These studies show 1) ADAM10 and APLP2 are expressed in proximal tubule cells and, 2) ADAM10 activity has a pronounced effect on expression of specific brush-border proteins. We postulate that ADAM10 and APLP2 may represent elements of a here-to-fore unknown signaling pathway in proximal tubule that link events at the brush border with control of gene expression.
Aging and aerobic fitness affect the contribution of noradrenergic sympathetic nerves to the rapid cutaneous vasodilator response to local heating
Authors: Tew Garry A. , Saxton John M. , Klonizakis Markos , Moss James , Ruddock Alan D. , Hodges Gary J.
Published: February 2011

Sedentary aging results in a diminished rapid cutaneous vasodilator response to local heating. We investigated whether this diminished response was due to altered contributions of noradrenergic sympathetic nerves by assessing 1) the age-related decline and 2) the effect of aerobic fitness. Using laser-Doppler flowmetry, we measured skin blood flow (SkBF) in young (24 ± 1 yr) and older (64 ± 1 yr) endurance-trained and sedentary men ( n = 7 per group) at baseline and during 35 min of local skin heating to 42°C at 1) untreated forearm sites, 2) forearm sites treated with bretylium tosylate (BT), which prevents neurotransmitter release from noradrenergic sympathetic nerves, and 3) forearm sites treated with yohimbine + propranolol (YP), which antagonizes α- and β-adrenergic receptors. SkBF was converted to cutaneous vascular conductance (CVC = SkBF/mean arterial pressure) and normalized to maximal CVC (%CVCmax) achieved by skin heating to 44°C. Pharmacological agents were administered using microdialysis. In the young trained group, the rapid vasodilator response was reduced at BT and YP sites ( P < 0.05); by contrast, in the young sedentary and older trained groups, YP had no effect ( P > 0.05), but BT did ( P > 0.05). Neither BT nor YP affected the rapid vasodilator response in the older sedentary group ( P > 0.05). These data suggest that the age-related reduction in the rapid vasodilator response is due to an impairment of sympathetic-dependent mechanisms, which can be partly attenuated with habitual aerobic exercise. Rapid vasodilation involves noradrenergic neurotransmitters in young trained men and nonadrenergic sympathetic cotransmitters (e.g., neuropeptide Y) in young sedentary and older trained men, possibly as a compensatory mechanism. Finally, in older sedentary men, the rapid vasodilation appears not to involve the sympathetic system.
RapidRadio: A Domain-Specific Productivity Enhancing Framework
Authors: Surís Jorge A. , Recio Adolfo , Athanas Peter
Published: February 2011

The RapidRadio framework for signal classification and receiver deployment is discussed. The framework is a productivity enhancing tool that reduces the required knowledge-base for implementing a receiver on an FPGA-based SDR platform. The ultimate objective of this framework is to identify unknown signals and to build FPGA-based receivers capable of receiving them. The architecture of the receiver deployed by the framework and its implementation are discussed. The framework's capacity to classify a signal and deploy a functional receiver is validated with over-the-air experiments.
Vascular Pathology and Blood-Brain Barrier Disruption in Cognitive and Psychiatric Complications of Type 2 Diabetes Mellitus
Authors: Serlin Yonatan , Levy Jaime , Shalev Hadar
Published: February 2011

Vascular pathology is recognized as a principle insult in type 2 diabetes mellitus (T2DM). Co-morbidities such as structural brain abnormalities, cognitive, learning and memory deficits are also prevailing in T2DM patients. We previously suggested that microvascular pathologies involving blood-brain barrier (BBB) breakdown results in leakage of serum-derived components into the brain parenchyma, leading to neuronal dysfunction manifested as psychiatric illnesses. The current postulate focuses on the molecular mechanisms controlling BBB permeability in T2DM, as key contributors to the pathogenesis of mental disorders in patients. Revealing the mechanisms underlying BBB dysfunction and inflammatory response in T2DM and their role in metabolic disturbances, abnormal neurovascular coupling and neuronal plasticity, would contribute to the understanding of the mechanisms underlying psychopathologies in diabetic patients. Establishing this link would offer new targets for future therapeutic interventions.
Titanium-Nickel Shape Memory Alloy Spring Actuator for Forward-Looking Active Catheter
Authors: Namazu Takahiro , Komatsubara Mamoru , Nagasawa Hiroyuki , Miki Takahiro , Tsurui Takafumi , Inoue Shozo
Published: February 2011

The fabrication and characterization of forward-looking active catheter actuated by titanium-nickel (Ti-Ni) shape memory alloy (SMA) springs are described. The catheter has been designed for wide-range observation of an affected area inside a blood vessel when the blood vessel is occluded. The developed active catheter consists of eight Ti-Ni SMA spring actuators for actuation of catheter tip, an ultrasonic transducer for forward-looking, a guide wire, a polyurethane tube for coating, and spiral wirings for realization of various flexure motions of catheter tip using Ti-Ni SMA actuators. The size of the catheter is 3.5 mm in diameter and 60 mm in length of the sum of transducer and actuator sections. Ti-Ni SMA springs were fabricated from a Ti-50.9at.%Ni sheet by electrochemical etching with a mixed solution of ethanol and lithium chloride. The catheter was assembled by hand under a stereomicroscope. The tip of the produced catheter was able to move in parallel toward at least eight directions by controlling an applied current to Ti-Ni SMA springs. We have confirmed that the active catheter was able to observe an object settled in the front.
Weight Gain Is Associated with an Increased Risk of Prostate Cancer Recurrence after Prostatectomy in the PSA Era
Authors: Joshu Corinne E. , Mondul Alison M. , Menke Andy , Meinhold Cari , Han Misop , Humphreys Elizabeth B. , Freedland Stephen J. , Walsh Patrick C. , Platz Elizabeth A.
Published: February 2011

Although obesity at the time of prostatectomy has been associated with prostate cancer recurrence, it is unknown whether obesity before or after surgery, or weight change from the years prior to surgery to after surgery is associated with recurrence. Thus, we examined the influence of obesity and weight change on recurrence after prostatectomy. We conducted a retrospective cohort study of 1,337 men with clinically localized prostate cancer who underwent prostatectomy performed during 1993–2006 by the same surgeon. Men self-reported weight and physical activity at 5 years before and 1 year after surgery on a survey during follow-up. Mean follow-up was 7.3 years. We estimated multivariable-adjusted HRs of prostate cancer recurrence comparing obesity at 5 years before and at 1 year after surgery with normal weight, and a gain of more than 2.2 kg from 5 years before to 1 year after surgery with stable weight. During 9,797 person years of follow-up, 102 men recurred. Compared with men who had stable weight, those whose weight increased by more than 2.2 kg had twice the recurrence risk (HR = 1.94; 95% CI, 1.14–3.32) after taking into account age, pathologic stage and grade, and other characteristics. The HR of recurrence was 1.20 (95% CI, 0.64–2.23) and 1.72 (95% CI, 0.94–3.14) comparing obesity at 5 years before and at 1 year after surgery, respectively, with normal weight. Physical activity (≥5 h/wk) did not attenuate risk in men who gained more than 2.2 kg. By avoiding weight gain, men with prostate cancer may both prevent recurrence and improve overall well-being. Cancer Prev Res; 4(4); 544–51. ©2011 AACR.
Morphometric Assessments for the Prognostic Evaluation of Human Gliomas
Authors: Kararizou Evangelia G. , Davaki Panajota T. , Davou Roubini G. , Vassilopoulos Demetrios
Published: February 2011

Backgroundand Aim: To correlate stereological parameters to the WHO morphological classification of brain tumours and to address the prognostic value of the different parameters. Methods and Materials: A quantitative analysis of 50 astrocytomas was performed by an image analysis system. At least 450 nuclei were counted and measured in every sample. The ANOVA 1-way test and Newman-Keuls modification were used for statistical evaluation. Results: The morphometric data showed significant differences between the tumour grades. We found the nuclear volume and form factor to be parameters of the degree of ‘nuclear atypia’ from low- to high-grade gliomas. When malignancy was increased, the mean values of nuclear orientation were found to be elevated. Conclusions: The results of our study underline the usefulness of morphometric techniques in tumour research. These techniques seem to be an important tool for grading gliomas and also for practical therapeutic purposes.
The Allometry of Brain Miniaturization in Ants
Authors: Seid Marc A. , Castillo Armando , Wcislo William T.
Published: February 2011

Extensive studies of vertebrates have shown that brain size scales to body size following power law functions. Most animals are substantially smaller than vertebrates, and extremely small animals face significant challenges relating to nervous system design and function, yet little is known about their brain allometry. Within a well-defined monophyletic taxon, Formicidae (ants), we analyzed how brain size scales to body size. An analysis of brain allometry for individuals of a highly polymorphic leaf-cutter ant, Atta colombica, shows that allometric coefficients differ significantly for small (<1.4 mg body mass) versus large individuals (b = 0.6003 and 0.2919, respectively). Interspecifically, allometric patterns differ for small (<0.9 mg body mass) versus large species (n = 70 species). Using mean values for species, the allometric coefficient for smaller species (b = 0.7961) is significantly greater than that for larger ones (b = 0.669). The smallest ants had brains that constitute ∼15% of their body mass, yet their brains were relatively smaller than predicted by an overall allometric coefficient of brain to body size. Our comparative and intraspecific studies show the extent to which nervous systems can be miniaturized in taxa exhibiting behavior that is apparently comparable to that of larger species or individuals.
Switching from Neural Networks (PAPNET) to the Imager (Hologic) for Computer-Assisted Screening
Authors: Boon Mathilde E. , Ouwerkerk-Noordam Elisabeth , Meijer-Marres Elisabeth M. , Bontekoe T. Romke
Published: February 2011

Objective: The large set of ThinPrep slides prepared in the Leiden Cytology and Pathology Laboratory is exploited for calculating the impact of the transition from PAPNET neural network scanning to the Imager technology. Study Design: All cervical samples were suspended and fixed in the coagulant fixative BoonFix. We compared 57,541 ThinPrep slides which were scanned by PAPNET and 64,273 ThinPrep slides processed with the Imager: 99,157 cases originated from the Dutch population screening program of asymptomatic women (screenees) and the remaining 22,657 samples were of symptomatic women. In the PAPNET series, 23% were diagnosed by additional light microscopy; in the Imager method, all slides were studied light microscopically. The cytoscores (positive cytology per 1,000 samples) were calculated for normal, atypical squamous cells of undetermined significance (ASC-US), cervical intraepithelial neoplasia (CIN) grades I–II, and for CIN III+. The odds ratios (ORs) for the positive cytoscores were assessed for both the screenees and the symptomatic women. Results: The cytoscores, per 1,000 cases, for ASC-US varied from 17.77 to 40.59, for CIN I–II from 7.17 to 33.35, and for CIN III+ from 2.81 to 8.8. These 6 cytoscores were higher for symptomatic women than for screenees. We observe significantly elevated ORs for the Imager for ASC-US (1.26 and 1.23), CIN I–II (1.45) and for CIN III+ (1.58 and 1.45). These 3 ORs are higher for screenees than for symptomatic women. Conclusion: The Imager technology is more efficacious, particularly for handling screenee slides.
Congenital Heart Defects in Europe
Authors: Dolk Helen , Loane Maria , Garne Ester ,   a European Surveillance of Congenital Anomalies (EUROCAT) Working Group
Published: February 2011

Background—

This study determines the prevalence of Congenital Heart Defects (CHD), diagnosed prenatally or in infancy, and fetal and perinatal mortality associated with CHD in Europe.

Methods and Results—

Data were extracted from the European Surveillance of Congenital Anomalies central database for 29 population-based congenital anomaly registries in 16 European countries covering 3.3 million births during the period 2000 to 2005. CHD cases (n=26 598) comprised live births, fetal deaths from 20 weeks gestation, and terminations of pregnancy for fetal anomaly (TOPFA). The average total prevalence of CHD was 8.0 per 1000 births, and live birth prevalence was 7.2 per 1000 births, varying between countries. The total prevalence of nonchromosomal CHD was 7.0 per 1000 births, of which 3.6% were perinatal deaths, 20% prenatally diagnosed, and 5.6% TOPFA. Severe nonchromosomal CHD (ie, excluding ventricular septal defects, atrial septal defects, and pulmonary valve stenosis) occurred in 2.0 per 1000 births, of which 8.1% were perinatal deaths, 40% were prenatally diagnosed, and 14% were TOPFA (TOPFA range between countries 0% to 32%). Live-born CHD associated with Down syndrome occurred in 0.5 per 1000 births, with >4-fold variation between countries.

Conclusion—

Annually in the European Union, we estimate 36 000 children are live born with CHD and 3000 who are diagnosed with CHD die as a TOFPA, late fetal death, or early neonatal death. Investing in primary prevention and pathogenetic research is essential to reduce this burden, as well as continuing to improve cardiac services from in utero to adulthood.
Comparison of the Structure of the Aortic Valve and Ascending Aorta in Adults Having Aortic Valve Replacement for Aortic Stenosis Versus for Pure Aortic Regurgitation and Resection of the Ascending Aorta for Aneurysm
Authors: Roberts William Clifford , Vowels Travis James , Ko Jong Mi , Filardo Giovanni , Hebeler Robert Frederick , Henry Albert Carl , Matter Gregory John , Hamman Baron Lloyd
Published: February 2011

Background—

There is debate concerning whether an aneurysmal ascending aorta should be replaced when associated with a dysfunctioning aortic valve that is to be replaced. To examine this issue, we divided the patients by type of aortic valve dysfunction—either aortic stenosis (AS) or pure aortic regurgitation (AR)—something not previously undertaken.

Methods and Results—

Of 122 patients with ascending aortic aneurysm (unassociated with aortitis or acute dissection), the aortic valve was congenitally malformed (unicuspid or bicuspid) in 58 (98%) of the 59 AS patients, and in 38 (60%) of the 63 pure AR patients. Ascending aortic medial elastic fiber loss (EFL) (graded 0 to 4+) was zero or 1+ in 53 (90%) of the AS patients, in 20 (53%) of the 38 AR patients with bicuspid valves, and in all 12 AR patients with tricuspid valves unassociated with the Marfan syndrome. An unadjusted analysis showed that, among the 96 patients with congenitally malformed valves, the 38 AR patients had a significantly higher likelihood of 2+ to 4+ EFL than the 58 AS patients (crude odds ratio: 8.78; 95% confidence interval: 2.95, 28.13).

Conclusions—

These data strongly suggest that the type of aortic valve dysfunction—AS versus pure AR—is very helpful in predicting loss of aortic medial elastic fibers in patients with ascending aortic aneurysms and aortic valve disease.
To Each Body a Spirit: Jewett and African Americans
Authors: Heller Terry
Published: February 2011

Many contemporary scholars accept that, until near the end of her career, Sarah Orne Jewett participated in the American construction of the superiority of whiteness by affirming almost universal nineteenth-century essentialist beliefs about racial hierarchy. This essay tests that interpretation by examining her fictional representations of African Americans.
In the Belly of the Beast: Hawthorne in England
Authors: Milder Robert
Published: February 2011

Hawthorne's years in England, the least studied phase of his career, are especially significant for the challenge that English materialism posed to his New England austerity and his romancer's idealism. Beyond recording his complex response to English life and character, his “English Notebooks” and “Our Old Home” show how England permanently inflected his character and sense of experience.
“The Dear Old Regiment”: Maine's Regimental Associations and the Memory of the American Civil War
Authors: Burton Crompton B.
Published: February 2011

When Maine veterans marched home after Appomattox, many sought to preserve connections with former comrades-in-arms and share Civil War experiences. They formed regimental associations, some of which persevered to publish invaluable unit histories. These narratives describe not only the conflict's events but its enduring impact upon its survivors as well.
Flood risk, vulnerability and environmental justice: Evidence and evaluation of inequality in a UK context
Authors: Walker Gordon , Burningham Kate
Published: February 2011

Flooding has only relatively recently been considered as an environmental justice issue. In this paper we focus on flooding as a distinct form of environmental risk and examine some of the key evidence and analysis that is needed to underpin an environmental justice framing of flood risk and flood impacts. We review and examine the UK situation and the body of existing research literature on flooding to fill out our understanding of the patterns of social inequality that exist in relation to both flood risk exposure and vulnerability to the diverse impacts of flooding. We then consider the various ways in which judgements might be made about the injustice or justice of these inequalities and the ways in which they are being sustained or responded to by current flood policy and practice. We conclude that there is both evidence of significant inequalities and grounds on which claims of injustice might be made, but that further work is needed to investigate each of these. The case for pursuing the framing of flooding as an environmental justice issue is also made.
Catalytic domain modification and viral gene delivery of activated factor VII confers hemostasis at reduced expression levels and vector doses in vivo
Authors: Margaritis Paris , Roy Elise , Faella Armida , Downey Harre D. , Ivanciu Lacramioara , Pavani Giulia , Zhou Shangzhen , Bunte Ralph M. , High Katherine A.
Published: February 2011

Catalytic domain variants of activated factor VII (FVIIa) with enhanced hemostatic properties are highly attractive for the treatment of bleeding disorders via gene-based therapy. To explore this in a hemophilic mouse model, we characterized 2 variants of murine activated FVII (mFVIIa-VEAY and mFVIIa-DVQ) with modified catalytic domains, based on recombinant human FVIIa (rhFVIIa) variants. Using purified recombinant proteins, we showed that murine FVIIa (mFVIIa) and variants had comparable binding to human and murine tissue factor (TF) and exhibited similar extrinsic coagulant activity. In vitro in the absence of TF, the variants showed a 6- to 17-fold enhanced proteolytic and coagulant activity relative to mFVIIa, but increased inactivation by antithrombin. Gene delivery of mFVIIa-VEAY resulted in long-term, effective hemostasis at 5-fold lower expression levels relative to mFVIIa in hemophilia A mice or in hemophilia B mice with inhibitors to factor IX. However, expression of mFVIIa-VEAY at 14-fold higher than therapeutic levels resulted in a progressive mortality to 70% within 6 weeks after gene delivery. These results are the first demonstration of the hemostatic efficacy of continuous expression, in the presence or absence of inhibitors, of a high-activity gene-based FVIIa variant in an animal model of hemophilia.
Travelling in time with networks: Revealing present day hybridization versus ancestral polymorphism between two species of brown algae, Fucus vesiculosus and F. spiralis
Authors: Moalic Yann , Arnaud-Haond Sophie , Perrin Cécile , Pearson Gareth A , Serrao Ester A
Published: February 2011

Background

Hybridization or divergence between sympatric sister species provides a natural laboratory to study speciation processes. The shared polymorphism in sister species may either be ancestral or derive from hybridization, and the accuracy of analytic methods used thus far to derive convincing evidence for the occurrence of present day hybridization is largely debated.

Results

Here we propose the application of network analysis to test for the occurrence of present day hybridization between the two species of brown algae Fucus spiralis and F. vesiculosus. Individual-centered networks were analyzed on the basis of microsatellite genotypes from North Africa to the Pacific American coast, through the North Atlantic. Two genetic distances integrating different time steps were used, the Rozenfeld (RD; based on alleles divergence) and the Shared Allele (SAD; based on alleles identity) distances. A diagnostic level of genotype divergence and clustering of individuals from each species was obtained through RD while screening for exchanges through putative hybridization was facilitated using SAD. Intermediate individuals linking both clusters on the RD network were those sampled at the limits of the sympatric zone in Northwest Iberia.

Conclusion

These results suggesting rare hybridization were confirmed by simulation of hybrids and F2 with directed backcrosses. Comparison with the Bayesian method STRUCTURE confirmed the usefulness of both approaches and emphasized the reliability of network analysis to unravel and study hybridization
Advancing the STMS genomic resources for defining new locations on the intraspecific genetic linkage map of chickpea (Cicer arietinum L.)
Authors: Gaur Rashmi , Sethy Niroj K , Choudhary Shalu , Shokeen Bhumika , Gupta Varsha , Bhatia Sabhyata
Published: February 2011

Background

Chickpea (Cicer arietinum L.) is an economically important cool season grain legume crop that is valued for its nutritive seeds having high protein content. However, several biotic and abiotic stresses and the low genetic variability in the chickpea genome have continuously hindered the chickpea molecular breeding programs. STMS (Sequence Tagged Microsatellite Sites) markers which are preferred for the construction of saturated linkage maps in several crop species, have also emerged as the most efficient and reliable source for detecting allelic diversity in chickpea. However, the number of STMS markers reported in chickpea is still limited and moreover exhibit low rates of both inter and intraspecific polymorphism, thereby limiting the positions of the SSR markers especially on the intraspecific linkage maps of chickpea. Hence, this study was undertaken with the aim of developing additional STMS markers and utilizing them for advancing the genetic linkage map of chickpea which would have applications in QTL identification, MAS and for de novo assembly of high throughput whole genome sequence data.

Results

A microsatellite enriched library of chickpea (enriched for ( GT/CA)n and (GA/CT)n repeats) was constructed from which 387 putative microsatellite containing clones were identified. From these, 254 STMS primers were designed of which 181 were developed as functional markers. An intraspecific mapping population of chickpea, [ICCV-2 (single podded) × JG-62 (double podded)] and comprising of 126 RILs, was genotyped for mapping. Of the 522 chickpea STMS markers (including the double-podding trait, screened for parental polymorphism, 226 (43.3%) were polymorphic in the parents and were used to genotype the RILs. At a LOD score of 3.5, eight linkage groups defining the position of 138 markers were obtained that spanned 630.9 cM with an average marker density of 4.57 cM. Further, based on the common loci present between the current map and the previously published chickpea intraspecific map, integration of maps was performed which revealed improvement of marker density and saturation of the region in the vicinity of sfl (double-podding) gene thereby bringing about an advancement of the current map.

Conclusion

An arsenal of 181 new chickpea STMS markers was reported. The developed intraspecific linkage map defined map positions of 138 markers which included 101 new locations.Map integration with a previously published map was carried out which revealed an advanced map with improved density. This study is a major contribution towards providing advanced genomic resources which will facilitate chickpea geneticists and molecular breeders in developing superior genotypes with improved traits.
The hyl
Efm
gene in pHylEfm of Enterococcus faecium is not required in pathogenesis of murine peritonitis
Authors: Panesso Diana , Montealegre Maria C , Rincón Sandra , Mojica Maria F , Rice Louis B , Singh Kavindra V , Murray Barbara E , Arias Cesar A
Published: February 2011

Background

Plasmids containing hyl

Efm
(pHylEfm) were previously shown to increase gastrointestinal colonization and lethality of Enterococcus faecium in experimental peritonitis. The hyl

Efm
gene, predicting a glycosyl hydrolase, has been considered as a virulence determinant of hospital-associated E. faecium, although its direct contribution to virulence has not been investigated. Here, we constructed mutants of the hyl

Efm
-region and we evaluated their effect on virulence using a murine peritonitis model.

Results

Five mutants of the hyl

Efm
-region of pHylEfmTX16 from the sequenced endocarditis strain (TX16 [DO]) were obtained using an adaptation of the PheS* system and were evaluated in a commensal strain TX1330RF to which pHylEfmTX16 was transferred by mating; these include i) deletion of hyl

Efm
only; ii) deletion of the gene downstream of hyl

Efm
(down) of unknown function; iii) deletion of hyl

Efm
plus down; iv) deletion of hyl

Efm
-down and two adjacent genes; and v) a 7,534 bp deletion including these four genes plus partial deletion of two others, with replacement by cat. The 7,534 bp deletion did not affect virulence of TX16 in peritonitis but, when pHylEfmTX16Δ7,534 was transferred to the TX1330RF background, the transconjugant was affected in in vitro growth versus TX1330RF(pHylEfmTX16) and was attenuated in virulence; however, neither hyl

Efm
nor hyl

Efm
-down restored wild type function. We did not observe any in vivo effect on virulence of the other deletions of the hyl

Efm
-region

Conclusions

The four genes of the hyl

Efm
region (including hyl

Efm
) do not mediate the increased virulence conferred by pHylEfmTX16 in murine peritonitis. The use of the markerless counterselection system PheS* should facilitate the genetic manipulation of E. faecium in the future.
Identification of potential target genes for the tomato fruit-ripening regulator RIN by chromatin immunoprecipitation
Authors: Fujisawa Masaki , Nakano Toshitsugu , Ito Yasuhiro
Published: February 2011

Background

During ripening, climacteric fruits increase their ethylene level and subsequently undergo various physiological changes, such as softening, pigmentation and development of aroma and flavor. These changes occur simultaneously and are caused by the highly synchronized expression of numerous genes at the onset of ripening. In tomatoes, the MADS-box transcription factor RIN has been regarded as a key regulator responsible for the onset of ripening by acting upstream of both ethylene- and non-ethylene-mediated controls. However, except forLeACS2, direct targets of RIN have not been clarified, and little is known about the transcriptional cascade for ripening.

Results

Using immunoprecipitated (IPed) DNA fragments recovered by chromatin immunoprecipitation (ChIP) with anti-RIN antibody from ripening tomato fruit, we analyzed potential binding sites for RIN (CArG-box sites) in the promoters of representative ripening-induced genes by quantitative PCR. Results revealed nearly a 5- to 20-fold enrichment of CArG boxes in the promoters ofLeACS2,LeACS4,PG,TBG4,LeEXP1, andLeMAN4and ofRINitself, indicating direct interaction of RIN with their promotersin vivo. Moreover, sequence analysis and genome mapping of 51 cloned IPed DNAs revealed potential RIN binding sites. Quantitative PCR revealed that four of the potential binding sites were enriched 4- to 17-fold in the IPed DNA pools compared with the controls, indicating direct interaction of RIN with these sitesin vivo. Near one of the four CArG boxes we found a gene encoding a protein similar to thioredoxin y1. An increase in the transcript level of this gene was observed with ripening in normal fruit but not in therinmutant, suggesting that RIN possibly induces its expression.

Conclusions

The presented results suggest that RIN controls fruit softening and ethylene production by the direct transcriptional regulation of cell-wall-modifying genes and ethylene biosynthesis genes during ripening. Moreover, the binding of RIN to its own promoter suggests the presence of autoregulation forRINexpression. ChIP-based analyses identified a novel RIN-binding CArG-box site that harbors a gene associated withRINexpression in its flanking region. These findings clarify the crucial role of RIN in the transcriptional regulation of ripening initiation and progression.
Variability in school closure decisions in response to 2009 H1N1: a qualitative systems improvement analysis
Authors: Klaiman Tamar , Kraemer John D , Stoto Michael A
Published: February 2011

Background

School closure was employed as a non-pharmaceutical intervention against pandemic 2009 H1N1, particularly during the first wave. More than 700 schools in the United States were closed. However, closure decisions reflected significant variation in rationales, decision triggers, and authority for closure. This variability presents the opportunity for improved efficiency and decision-making.

Methods

We identified media reports relating to school closure as a response to 2009 H1N1 by monitoring high-profile sources and searching Lexis-Nexis and Google news alerts, and reviewed reports for key themes. News stories were supplemented by observing conference calls and meetings with health department and school officials, and by discussions with decision-makers and community members.

Results

There was significant variation in the stated goal of closure decision, including limiting community spread of the virus, protecting particularly vulnerable students, and responding to staff shortages or student absenteeism. Because the goal of closure is relevant to its timing, nature, and duration, unclear rationales for closure can challenge its effectiveness. There was also significant variation in the decision-making authority to close schools in different jurisdictions, which, in some instances, was reflected in open disagreement between school and public health officials. Finally, decision-makers did not appear to expect the level of scientific uncertainty encountered early in the pandemic, and they often expressed significant frustration over changing CDC guidance.

Conclusions

The use of school closure as a public health response to epidemic disease can be improved by ensuring that officials clarify the goals of closure and tailor closure decisions to those goals. Additionally, authority to close schools should be clarified in advance, and decision-makers should expect to encounter uncertainty disease emergencies unfold and plan accordingly.
Modified Alvarado Scoring System as a diagnostic tool for Acute Appendicitis at Bugando Medical Centre, Mwanza, Tanzania
Authors: Kanumba Emmanuel S , Mabula Joseph B , Rambau Peter , Chalya Phillipo L
Published: February 2011

Background

Decision-making in patients with acute appendicitis poses a diagnostic challenge worldwide, despite much advancement in abdominal surgery. The Modified Alvarado Scoring System (MASS) has been reported to be a cheap and quick diagnostic tool in patients with acute appendicitis. However, differences in diagnostic accuracy have been observed if the scores were applied to various populations and clinical settings. The purpose of this study was to evaluate the diagnostic value of Modified Alvarado Scoring System in patients with acute appendicitis in our setting.

Methods

A cross-sectional study involving all patients suspected to have acute appendicitis at Bugando Medical Centre over a six-month period between November 2008 and April 2009 was conducted. All patients who met the inclusion criteria were consecutively enrolled in the study. They were evaluated on admission using the MASS to determine whether they had acute appendicitis or not. All patients underwent appendicectomy according to the hospital protocol. The decision to operate was the prerogative of the surgeon or surgical resident based on overall clinical judgment and not the MASS. The diagnosis was confirmed by histopathological examination. Data was collected using a pre-tested coded questionnaire and analyzed using SPSS statistical computer software.

Results

A total number of 127 patients were studied. Their ages ranged from eight to 76 years (mean 29.64 ± 12.97). There were 37 (29.1%) males and 90 (70.9%) females (M: F = 1:2.4). All patients in this study underwent appendicectomy. The perforation rate was 9.4%. Histopathological examination confirmed appendicitis in 85 patients (66.9%) and the remaining 42 patients had normal appendix giving a negative appendicectomy rate of 33.1% (26.8% for males and 38.3% for females). The sensitivity and specificity of MASS in this study were 94.1% (males 95.8% and females 88.3%) and 90.4% (males 92.9% and females 89.7%) respectively. The Positive Predictive Value and Negative Predictive Value were 95.2% (males 95.5% and females 90.6%) and 88.4% (males 89.3% and females 80.1%) respectively. The accuracy of MASS was 92.9% (males 91.5% and females 87.6%).

Conclusion

The study shows that use of MASS in patients suspected to have acute appendicitis provides a high degree of diagnostic accuracy and can be employed at Bugando Medical Centre to improve the diagnostic accuracy of acute appendicitis and subsequently reduces negative appendicectomy and complication rates. However, additional investigations may be required to confirm the diagnosis in case of atypical presentation.
Response to mTOR inhibition: activity of eIF4E predicts sensitivity in cell lines and acquired changes in eIF4E regulation in breast cancer
Authors: Satheesha Sampoorna , Cookson Victoria J , Coleman Louise J , Ingram Nicola , Madhok Brijesh , Hanby Andrew M , Suleman Charlotte AB , Sabine Vicky S , Macaskill E Jane , Bartlett John MS , Dixon J Michael , McElwaine Jim N , Hughes Thomas A
Published: February 2011

Background

Inhibitors of the kinase mTOR, such as rapamycin and everolimus, have been used as cancer therapeutics with limited success since some tumours are resistant. Efforts to establish predictive markers to allow selection of patients with tumours likely to respond have centred on determining phosphorylation states of mTOR or its targets 4E-BP1 and S6K in cancer cells. In an alternative approach we estimated eIF4E activity, a key effector of mTOR function, and tested the hypothesis that eIF4E activity predicts sensitivity to mTOR inhibition in cell lines and in breast tumours.

Results

We found a greater than three fold difference in sensitivity of representative colon, lung and breast cell lines to rapamycin. Using an assay to quantify influences of eIF4E on the translational efficiency specified by structured 5'UTRs, we showed that this estimate of eIF4E activity was a significant predictor of rapamycin sensitivity, with higher eIF4E activities indicative of enhanced sensitivity. Surprisingly, non-transformed cell lines were not less sensitive to rapamycin and did not have lower eIF4E activities than cancer lines, suggesting the mTOR/4E-BP1/eIF4E axis is deregulated in these non-transformed cells. In the context of clinical breast cancers, we estimated eIF4E activity by analysing expression of eIF4E and its functional regulators within tumour cells and combining these scores to reflect inhibitory and activating influences on eIF4E. Estimates of eIF4E activity in cancer biopsies taken at diagnosis did not predict sensitivity to 11-14 days of pre-operative everolimus treatment, as assessed by change in tumour cell proliferation from diagnosis to surgical excision. However, higher pre-treatment eIF4E activity was significantly associated with dramatic post-treatment changes in expression of eIF4E and 4E-binding proteins, suggesting that eIF4E is further deregulated in these tumours in response to mTOR inhibition.

Conclusions

Estimates of eIF4E activity predict sensitivity to mTOR inhibition in cell lines but breast tumours with high estimated eIF4E activity gain changes in eIF4E regulation in order to enhance resistance.
Inorganic nanotubes reinforced polyvinylidene fluoride composites as low-cost electromagnetic interference shielding materials
Authors: Eswaraiah Varrla , Sankaranarayanan Venkataraman , Ramaprabhu Sundara
Published: February 2011

Novel polymer nanocomposites comprising of MnO2 nanotubes (MNTs), functionalized multiwalled carbon nanotubes (f-MWCNTs), and polyvinylidene fluoride (PVDF) were synthesized. Homogeneous distribution of f-MWCNTs and MNTs in PVDF matrix were confirmed by field emission scanning electron microscopy. Electrical conductivity measurements were performed on these polymer composites using four probe technique. The addition of 2 wt.% of MNTs (2 wt.%, f-MWCNTs) to PVDF matrix results in an increase in the electrical conductivity from 10-16S/m to 4.5 × 10-5S/m (3.2 × 10-1S/m). Electromagnetic interference shielding effectiveness (EMI SE) was measured with vector network analyzer using waveguide sample holder in X-band frequency range. EMI SE of approximately 20 dB has been obtained with the addition of 5 wt.% MNTs-1 wt.% f-MWCNTs to PVDF in comparison with EMI SE of approximately 18 dB for 7 wt.% of f-MWCNTs indicating the potential use of the present MNT/f-MWCNT/PVDF composite as low-cost EMI shielding materials in X-band region.
Luminescence of colloidal CdSe/ZnS nanoparticles: high sensitivity to solvent phase transitions
Authors: Antipov Andrei , Bell Matt , Yasar Mesut , Mitin Vladimir , Scharmach William , Swihart Mark , Verevkin Aleksandr , Sergeev Andrei
Published: February 2011

We investigate nanosecond photoluminescence processes in colloidal core/shell CdSe/ZnS nanoparticles dissolved in water and found strong sensitivity of luminescence to the solvent state. Several pronounced changes have been observed in the narrow temperature interval near the water melting point. First of all, the luminescence intensity substantially (approximately 50%) increases near the transition. In a large temperature scale, the energy peak of the photoluminescence decreases with temperature due to temperature dependence of the energy gap. Near the melting point, the peak shows N-type dependence with the maximal changes of approximately 30 meV. The line width increases with temperature and also shows N-type dependence near the melting point. The observed effects are associated with the reconstruction of ligands near the ice/water phase transition.
Impact of AFM-induced nano-pits in a-Si:H films on silicon crystal growth
Authors: Verveniotis Elisseos , Rezek Bohuslav , Šípek Emil , Stuchlík Jiří , Ledinský Martin , Kočka Jan
Published: February 2011

Conductive tips in atomic force microscopy (AFM) can be used to localize field-enhanced metal-induced solid-phase crystallization (FE-MISPC) of amorphous silicon (a-Si:H) at room temperature down to nanoscale dimensions. In this article, the authors show that such local modifications can be used to selectively induce further localized growth of silicon nanocrystals. First, a-Si:H films by plasma-enhanced chemical vapor deposition on nickel/glass substrates are prepared. After the FE-MISPC process, yielding both conductive and non-conductive nano-pits in the films, the second silicon layer at the boundary condition of amorphous and microcrystalline growth is deposited. Comparing AFM morphology and current-sensing AFM data on the first and second layers, it is observed that the second deposition changes the morphology and increases the local conductivity of FE-MISPC-induced pits by up to an order of magnitude irrespective of their prior conductivity. This is attributed to the silicon nanocrystals (<100 nm) that tend to nucleate and grow inside the pits. This is also supported by micro-Raman spectroscopy.
Study of the formation processes of gold droplet arrays on Si substrates by high temperature anneals
Authors: Klimovskaya Alla , Sarikov Andrey , Pedchenko Yury , Voroshchenko Andrey , Lytvyn Oksana , Stadnik Alexandr
Published: February 2011

In this study, the peculiarities of the transformations of gold films deposited on the Si wafer surfaces as a result of high temperature anneals are investigated experimentally depending on the conditions of wafer surface preparation and the annealing regimes. The morphology and the distribution functions of the crystallites of gold films as well as the gold droplets formed as a result of anneals are studied as functions of annealing temperature, type of annealing (rapid thermal or rapid furnace annealing), and the state of the surface of Si wafers. The results obtained can be used for the controlled preparation of the arrays of catalytic gold droplets for subsequent growth of Si wire-like crystals.
Solvothermal synthesis of uniform bismuth nanospheres using poly(N-vinyl-2-pyrrolidone) as a reducing agent
Authors: Wu Jiliang , Qin Fan , Lu Zhong , Yang Hai-Jian , Chen Rong
Published: February 2011

Uniform bismuth nanospheres were successfully prepared from bismuth nitrate in the presence of poly(N-vinyl-2-pyrrolidone) (PVP) by solvothermal process. The product was characterized by powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, selected area electron diffraction, and energy-dispersive X-ray. PVP plays a critical role both as a reducing agent and a capping agent in the formation of bismuth nanospheres. Shape and size of bismuth nanospheres could be tuned by changing the employed PVP/bismuth salt ratio. It was also found the solvent had an effect on the morphologies of bismuth nanomaterials. The possible formation and growth mechanism of bismuth nanospheres were also discussed and proposed to explain the reduction step.