bluuebunny/crossref_metadata_2025_split huggingface dataset:
Outlier loci highlight the direction of introgression in oaks
Authors: Guichoux E. , Garnier‐Géré P. , Lagache L. , Lang T. , Boury C. , Petit R. J. 
Published: November 2012

AbstractLoci considered to be under selection are generally avoided in attempts to infer past demographic processes as they do not fit neutral model assumptions. However, opportunities to better reconstruct some aspects of past demography might thus be missed. Here we examined genetic differentiation between two sympatricEuropean oak species with contrasting ecological dynamics (Quercus roburandQuercus petraea) with both outlier (i.e. loci possibly affected by divergent selection between species or by hitchhiking effects with genomic regions under selection) and nonoutlier loci. We sampled 855 individuals in six mixed forests inFrance and genotyped them with a set of 262SNPs enriched with markers showing high interspecific differentiation, resulting in accurate species delimitation. We identified between 13 and 74 interspecific outlier loci, depending on the coalescent simulation models and parameters used. Greater genetic diversity was predicted inQ. petraea(a late‐successional species) than inQ. robur(an early successional species) as introgression should theoretically occur predominantly from the resident species to the invading species. Remarkably, this prediction was verified with outlier loci but not with nonoutlier loci. We suggest that the lower effective interspecific gene flow at loci showing high interspecific divergence has better preserved the signal of past asymmetric introgression towardsQ. petraeacaused by the species' contrasting dynamics. Using markers under selection to reconstruct past demographic processes could therefore have broader potential than generally recognized.
Does mating behaviour affect connectivity in marine fishes? Comparative population genetics of two protogynous groupers (Family Serranidae)
Authors: Portnoy D. S. , Hollenbeck C. M. , Renshaw M. A. , Cummings N. J. , Gold J. R. 
Published: November 2012

AbstractPelagic larval duration (PLD) has been hypothesized to be the primary predictor of connectivity in marine fishes; however, few studies have examined the effects that adult reproductive behaviour may have on realized dispersal. We assessed gene flow (connectivity) by documenting variation in microsatellites and mitochondrial DNA sequences in two protogynous species of groupers, the aggregate spawning red hind, Epinephelus guttatus, and the single‐male, harem‐spawning coney, Cephalopholis fulva, to ask whether reproductive strategy affects connectivity. Samples of both species were obtained from waters off three islands (Puerto Rico, St. Thomas and St. Croix) in the Caribbean Sea. Despite the notion that aggregate spawning of red hind may facilitate larval retention, stronger signals of population structure were detected in the harem‐spawning coney. Heterogeneity and/or inferred barriers, based on microsatellites, involved St. Croix (red hind and coney) and the west coast of Puerto Rico (coney). Heterogeneity and/or inferred barriers, based on mitochondrial DNA, involved St. Croix (coney only). Genetic divergence in both species was stronger for microsatellites than for mitochondrial DNA, suggesting sex‐biased dispersal in both species. Long‐term migration rates, based on microsatellites, indicated asymmetric gene flow for both species in the same direction as mean surface currents in the region. Red hind had higher levels of variation in microsatellites and lower levels of variation in mitochondrial DNA. Long‐term effective size and effective number of breeders were greater for red hind; estimates of θf, a proxy for long‐term effective female size, were the same in both species. Patterns of gene flow in both species appear to stem in part from shared aspects of larval and adult biology, local bathymetry and surface current patterns. Differences in connectivity and levels of genetic variation between the species, however, likely stem from differences in behaviour related to reproductive strategy.
Phosphatidylglycerophosphate synthase associates with a mitochondrial inner membrane complex and is essential for growth of Trypanosoma brucei
Authors: Serricchio Mauro , Bütikofer Peter 
Published: November 2012

SummaryMaintenance of the lipid composition is important for proper function and homeostasis of the mitochondrion. In Trypanosoma brucei, the enzymes involved in the biosynthesis of the mitochondrial phospholipid, phosphatidylglycerol (PG), have not been studied experimentally. We now report the characterization of T. brucei phosphatidylglycerophosphate synthase (TbPgps), the rate‐limiting enzyme in PG formation, which was identified based on its homology to other eukaryotic Pgps. Lipid quantification and metabolic labelling experiments show that TbPgps gene knock‐down results in loss of PG and a reduction of another mitochondria‐specific phospholipid, cardiolipin. Using immunohistochemistry and immunoblotting of digitonin‐isolated mitochondria, we show that TbPgps localizes to the mitochondrion. Moreover, reduced TbPgps expression in T. brucei procyclic forms leads to alterations in mitochondrial morphology, reduction in the amounts of respiratory complexes III and IV and, ultimately, parasite death. Using native polyacrylamide gel electrophoresis we demonstrate for the first time in a eukaryotic organism that TbPgps is a component of a 720 kDa protein complex, co‐migrating with T. brucei cardiolipin synthase and cytochrome c1, a protein of respiratory complex III.
Analysis of Two Kinds of Tree as Physical Barriers Against Erythemal UVB Radiation Received
Authors: Ysasi Gonzalo G. , Ribera Luis J. C. 
Published: November 2012

AbstractDifferences between global radiation UVER (erythemal ultraviolet solar radiation) received under full sun and diffuse radiation received under the shadow of two types of tree are analyzed to check the importance of these components on human exposure to UV radiation. Blue Line spores dosimeters of VioSpor were used for measurement of erythemal dose of UV radiation (able to produce erythema in human skin.) The response profile of these devices is extremely similar to human skin, thus they are suitable to determine and predict the interactions between UV erythema and human skin. Measurements were obtained in relatively clear days from February to December 2009 between 9:30 and 15:30 h. Three dosimeters were placed on a horizontal surface: one in full sun and the other two under the shadow of each tree. Values of UVER in both cases, in full sun and under the shadow of pine and Sauce, were obtained. In addition, the comparison was made between values of dose received in each case and the exposure limits recommended by the International Commission on Non‐Ionizing Radiation Protection (ICNIRP). Finally, average daily irradiance received under the shadow of each tree in comparison with those received in full sun, was also analyzed using two PMA2100 radiometers situated on a horizontal surface.
The Bovine Luteal Histological Composition: A Topographic Point of View
Authors: Cools S , Van den Broeck W , De Vliegher S , Piepers S , Opsomer G 
Published: November 2012

ContentsHigh‐yielding dairy cows are struggling with a high incidence of embryonic loss, among others caused by an insufficient peripheral progesterone concentration which for its part might be associated with an impaired luteal progesterone production. This impaired capacity to produce progesterone might be reflected in the histology of the gland. The aim of the present pilot study was the assessment of the variation in cell density within a bovine luteal gland (LG), to examine whether it is possible to analyse histologically the functionality of the gland based on one single tissue sample. Six LGs (stage II or III) were harvested out of just as many healthy cows at the slaughterhouse. The luteal cell density was assessed by calculating the nuclear density (ND) of the different luteal cell types on haematoxylin‐eosin‐stained histological sections from a number of topographic regions evenly spread throughout the glands, to give an overview of the pattern of cellular distribution within the whole gland. Cells were differentiated into ‘large luteal cells’, ‘small luteal cells’ and ‘non‐steroidogenic cells’. Results show that the cellular density, within a tissue sample is not significantly influenced by its location in relation to the gland's equatorial plane. However, the position with respect to the polar axis of the gland has a decisive effect, as the ND is significantly higher (p < 0.05) in the peripheral regions (outer zone) when compared with the central regions (inner zone) of the gland, and this counts for all three cell types.
High levels of jasmonic acid antagonize the biosynthesis of gibberellins and inhibit the growth of Nicotiana attenuata stems
Authors: Heinrich Maria , Hettenhausen Christian , Lange Theo , Wünsche Hendrik , Fang Jingjing , Baldwin Ian T. , Wu Jianqiang 
Published: November 2012

SummaryHormones play pivotal roles in regulating plant development, growth, and stress responses, and cross‐talk among different hormones fine‐tunes various aspects of plant physiology. Jasmonic acid (JA) is important for plant defense against herbivores and necrotic fungi and also regulates flower development; in addition, Arabidopsis mutants over‐producing JA usually have stunted stems and wound‐induced jasmonates suppress Arabidopsis growth, suggesting that JA is also involved in stem elongation. Gibberellins (GAs) promote stem and leaf growth and modulate seed germination, flowering time, and the development of flowers, fruits, and seeds. However, little is known about the interaction between the JA and GA pathways. Two calcium‐dependent protein kinases, CDPK4 and CDPK5, are important suppressors of JA accumulation in a wild tobacco species, Nicotiana attenuata. The stems of N. attenuata silenced in CDPK4 and CDPK5 (irCDPK4/5 plants) had dramatically increased levels of JA and exhibited stunted elongation and had very high contents of secondary metabolites. Genetic analysis indicated that the high JA levels in irCDPK4/5 stems accounted for the suppressed stem elongation and the accumulation of secondary metabolites. Supplementation of GA3 to irCDPK4/5 plants largely restored normal stem growth to wild‐type levels. Measures of GA levels indicated that over‐accumulation of JA in irCDPK4/5 stems inhibited the biosynthesis of GAs. Finally, we show that JA antagonizes GA biosynthesis by strongly inhibiting the transcript accumulation of GA20ox and possibly GA13ox, the key genes in GA production, demonstrating that high JA levels antagonize GA biosynthesis in stems.
Self‐adapting cyclic registration for motion‐compensated cone‐beam CT in image‐guided radiation therapy
Authors: Brehm Marcus , Paysan Pascal , Oelhafen Markus , Kunz Patrik , Kachelrieß Marc 
Published: November 2012

Purpose:In image‐guided radiation therapy an additional kV imaging system next to the linear particle accelerator provides information for an accurate patient positioning. However, the acquisition time of the system is much longer than the patientˈs breathing cycle due to the low gantry rotation speed. Our purpose is a cyclic registration in the context of motion‐compensated image reconstruction that provides high quality respiratory‐correlated 4D volumes for on‐board flat panel detector cone‐beam CT scans.Methods:Based on the small motion assumption, widely used within registration algorithms, a strategy is developed for motion estimation. In this strategy temporal restrictions are incorporated, for example, the cyclic motion patterns of respiration. The resultant cyclic registration method is to show less sensitivity on image artifacts, in particular on artifacts due to projection data sparsification. Using a new cyclic registration method a motion estimation is performed on respiratory‐correlated reconstructions, and the obtained motion vector fields are used for motion compensation.Results:The proposed cyclic registration is evaluated in the context of motion‐compensated image reconstruction using simulated data and patient data. Motion artifacts of 3D standard reconstructions can be significantly reduced by the resulting cyclic motion compensation. The method outperforms the respiratory‐correlated reconstructions regarding sparse‐view artifacts and maintains the high temporal resolution at the same time. Image artifacts show only minor to almost no effect on the motion estimation using the cyclic registration.Conclusions:The cyclic motion compensation approach provides respiratory‐correlated volumes with high image quality. The cyclic motion estimation is of such low sensitivity to sparse‐view artifacts, that it is capable to determine high quality motion vector fields based on reconstructions of low sampled data.
Delayed presentation of congenital diaphragmatic hernia presenting with intrathoracic gastric volvulus: a case report and review
Authors: Nayak Hemanta K , Maurya Gaurav , Kapoor Neha , Kar Premashis 
Published: November 2012

Acute gastric volvulus associated with congenital diaphragmatic hernia is an unusual surgical emergency and its presentation in adulthood is extremely rare. Gastric volvulus is an uncommon condition which is difficult to diagnose and treat. This case describes a middle aged man presenting with post-traumatic acute abdomen and finally being diagnosed as a case of gastric volvulus due to congenital diaphragmatic hernia which was till now asymptomatic and undiagnosed. Clinical examination and chest x-ray was suggestive of hiatus hernia. Contrast-enhanced CT of thorax and abdomen revealed hiatus hernia and gastric volvulus. A provisional diagnosis of post-traumatic hiatus hernia with associated gastric volvulus was made and was operated on an emergency basis. Surprisingly, the intraoperative findings revealed significant adhesions near the diaphragm suggestive of congenital diaphragmatic hernia. Hence, a diagnosis of gastric volvulus due to congenital diaphragmatic hernia was made which remained asymptomatic and undiagnosed till adulthood. He responded well to operative management and remained asymptomatic afterwards.
Comparison of British and French expatriate doctors’ characteristics and motivations
Authors: Quantin Catherine , Abbas Rachid , Hagi Mathieu , Breton Gwenaelle Le , Romestaing M , Carnet Dider 
Published: November 2012

ObjectiveThe aim of this study was to analyse the migration of doctors between the UK and France, in an attempt to identify the reasons for these migrations.DesignThis was a cross-sectional study conducted using a self-completed questionnaire.SettingThe questionnaire was sent to all British doctors practising in France and to all French doctors practising in the UK.ParticipantsThe doctors were identified, thanks to official data of the National Medical Councils. There were 244 French doctors practising in the UK and 86 British doctors practising in France.Outcome measuresA questionnaire was specifically developed for the study to determine the reasons why doctors moved to the other country and their level of satisfaction with regard to their expatriation.ResultsA total of 98 French doctors (of 244) and 40 British doctors (of 86) returned the questionnaire. The motivations of the two studied populations were different: French doctors were attracted by the conditions offered by the National Health Service, whereas British doctors were more interested in opportunities for career advancement, moved to join a husband or wife or to benefit from favourable environmental conditions. Overall, the doctors who responded considered the expatriation a satisfactory experience. After expatriation, 84% of French doctors were satisfied with their new professional situation compared with only 58% of British doctors.ConclusionsThis study, which is the first of its kind and based on representative samples, has led to a clearer understanding of the migration of doctors between France and the UK.
Capsaicin induces de-differentiation of activated hepatic stellate cell
Authors: Bitencourt Shanna , de Mesquita Fernanda C. , Caberlon Eduardo , da Silva Gabriela V. , Basso Bruno S. , Ferreira Gabriela A. , de Oliveira Jarbas R. 
Published: November 2012

Hepatic stellate cells (HSC) play a key role in liver fibrogenesis. Activation of PPARγ and inhibition of fibrogenic molecules are potential strategies to block HSC activation and differentiation. A number of natural products have been suggested to have antifibrotic effects for the de-activation and de-differentiation of HSCs. The purpose of this study was to investigate the in vitro effects of capsaicin on HSC de-activation and de-differentiation. The results demonstrated that capsaicin induced quiescent phenotype in GRX via PPARγ activation. Significant decrease in COX-2 and type I collagen mRNA expression was observed in the first 24 h of treatment. These events preceded the reduction of TGF-β1 and total collagen secretion. Thus, capsaicin promoted down-regulation of HSC activation by its antifibrotic and anti-inflammatory actions. These findings demonstrate that capsaicin may have potential as a novel therapeutic agent for the treatment of liver fibrosis.
Gambogic acid promotes apoptosis and resistance to metastatic potential in MDA-MB-231 human breast carcinoma cells
Authors: Li Chenglin , Qi Qi , Lu Na , Dai Qinsheng , Li Fanni , Wang Xiaotang , You Qidong , Guo Qinglong 
Published: November 2012

Gambogic acid (GA) is considered a potent anti-tumor agent for its multiple effects on cancer cells in vitro and in vivo. Low concentrations of GA (0.3–1.2 µmol/L) can suppress invasion of human breast carcinoma cells without affecting cell viability. To get a whole profile of the inhibition on breast cancers, higher concentrations of GA and spontaneous metastatic animal models were employed. Treatment with GA (3 and 6 µmol/L) induced apoptosis in MDA-MB-231 cells and the accumulation of reactive oxygen species (ROS). Furthermore, GA induced PARP cleavage, activation of caspase-3, caspase-8, and caspase-9, as well as an increased ratio of Bax/Bcl-2. Moreover, the translocation of apoptotic inducing factor (AIF) and the release of cytochrome c (Cyt c) from mitochondria were observed, indicating that GA induced apoptosis through accumulation of ROS and mitochondrial apoptotic pathway. GA also inhibited cell survival via blocking Akt/mTOR signaling. In vivo, GA significantly inhibited the xenograft tumor growth and lung metastases in athymic BALB/c nude mice bearing MDA-MB-231 cells. Collectively, these data provide further support for the multiple effects of GA on human breast cancer cells, as well as for its potential application to inhibit tumor growth and prevent metastasis in human cancers.
Self-healing in unattended wireless sensor networks
Authors: Pietro Roberto Di , Ma Di , Soriente Claudio , Tsudik Gene 
Published: November 2012

Wireless sensor networks (WSNs) appeal to a wide range of applications that involve the monitoring of various physical phenomena. However, WSNs are subject to many threats. In particular, lack of pervasive tamper-resistant hardware results in sensors being easy targets for compromise. Having compromised a sensor, the adversary learns all the sensor secrets, allowing it to later encrypt/decrypt or authenticate messages on behalf of that sensor. This threat is particularly relevant in the novel unattended wireless sensor networks (UWSNs) scenario. UWSNs operate without constant supervision by a trusted sink. UWSN's unattended nature and increased exposure to attacks prompts the need for special techniques geared towards regaining security after being compromised.
In this article, we investigate cooperative self-healing in UWSNs and propose various techniques to allow unattended sensors to recover security after compromise. Our techniques provide seamless healing rates even against a very agile and powerful adversary. The effectiveness and viability of our proposed techniques are assessed by thorough analysis and supported by simulation results. Finally, we introduce some real-world issues affecting UWSN deployment and provide some solutions for them as well as a few open problems calling for further investigation.
Dynamic process model for identifying modified data using mobile agents in real time ETL processes
Authors: Mrunalini M. , Kumar T. V. Suresh , Kanth K. Rajani 
Published: November 2012

Usability and accessibility issues are common causes why software fails to meet user requirements. However, requirements engineers still focus on functional requirements and might ignore to also elicit system usability and accessibility requirements. This is a high risk which can lead to project and software failure. Improving the usability and accessibility of a system in a later development stage is costly and time consuming. Targeting these concerns, the workshop envisioned that research must address the proper integration of system usability and accessibility requirements into the requirements engineering process and also must focus on how to manage and control the evaluation of these requirements in a systematic way.
UsARE 2012 provided a platform for discussing issues which are relevant for both fields, the Requirements Engineering (RE) and the Human Computer Interaction (HCI). The workshop aim was to bring\ together people from these two communities (RE and HCI) to explore this integration. Researchers and practitioners were invited to submit contributions including problem statements, technical solutions, experience reports, planned work and vision papers. Envisioned results may help aligning RE and HCI processes in order to overcome open issues in these fields.
Plk1 Phosphorylation of Orc2 and Hbo1 Contributes to Gemcitabine Resistance in Pancreatic Cancer
Authors: Song Bing , Liu X. Shawn , Rice Steven J. , Kuang Shihuan , Elzey Bennett D. , Konieczny Stephen F. , Ratliff Timothy L. , Hazbun Tony , Chiorean Elena G. , Liu Xiaoqi 
Published: November 2012

Abstract
Although gemcitabine is the standard chemotherapeutic drug for treatment of pancreatic cancer, almost all patients eventually develop resistance to this agent. Previous studies identified Polo-like kinase 1 (Plk1) as the mediator of gemcitabine resistance, but the molecular mechanism remains unknown. In this study, we show that Plk1 phosphorylation of Orc2 and Hbo1 mediates the resistance to gemcitabine. We show that the level of Plk1 expression positively correlates with gemcitabine resistance, both in pancreatic cancer cells and xenograft tumors. Overexpression of Plk1 increases gemcitabine resistance, while inhibition of Plk1 sensitizes pancreatic cancer cells to gemcitabine treatment. To validate our findings, we show that inhibition of Plk1 sensitizes tumors to gemcitabine treatment in a mouse xenograft study. Mechanistically, we find that Plk1 phosphorylation of Orc2 maintains DNA replication on gemcitabine treatment. Furthermore, Plk1 phosphorylation of Hbo1 transcriptionally increases cFos expression and consequently elevates its target multidrug resistance 1 (MDR1), which was previously reported to confer chemotherapeutic drug resistance. Knockdown of cFos or MDR1 sensitizes gemcitabine-resistant cells to gemcitabine treatment. Finally, pancreatic cancer cells expressing Plk1-unphosphorylatable mutants of Orc2 or Hbo1 are more sensitive to gemcitabine than cells expressing wild-type Orc2 or Hbo1. In short, our study provides a mechanism for Plk1-mediated gemcitabine resistance, suggesting that Plk1 is a promising target for treatment of gemcitabine-resistant pancreatic cancer. Mol Cancer Ther; 12(1); 58–68. ©2012 AACR.