bluuebunny/crossref_metadata_2025_split huggingface dataset:
Population genetics in a fragmented population of the European tree frog (Hyla arborea)
Authors: Krug Astrid , Pröhl Heike 
Published: February 2013

Habitat degradation and fragmentation are known to be major threats for population persistence in European amphibians. The European tree frog Hyla arborea has suffered from dramatic population declines in the last decades and has therefore been categorised as threatened in many Red Data lists. In the region of Hannover (Germany), the European tree frog has a fragmented distribution. The aim of our study was to infer the genetic consequences of habitat fragmentation in this area by examining genetic variation and population structure. DNA samples from 193 individuals from 11 sampling sites (10 sampling sites located 2 to 32 km apart from each other near Hannover and for comparison one sampling site 140 km northeast) were analysed with eight highly polymorphic microsatellite loci. Bayesian analyses indicated that the tree frog occurrences near Hannover were fragmented into four genetically distinct clusters according to their geographical distribution. Pairwise genetic distances between sampling sites varied between 0 and 0.23 (FST) and 0 and 0.48 (Dest) and indicated high to moderate gene flow within genetic clusters and nearly absent gene flow among genetic clusters. Moreover, we identified a potential source population within the region for an introduced population in the southwest of Hannover. Our data suggest that the genetic structure is influenced in part by isolation by distance and in part by lack of habitat or migration barriers. Habitat fragmentation should by counteracted by targeted conservation measures in areas where gaps in distribution and genetic fragmentation have been revealed.
Ring-Around-the-Rosie Atlantic: Transatlantic Uses of Rings Among Bata Drummers, Caravan Guards, and Muslim Insurgents
Authors: Marcuzzi Michael 
Published: February 2013

Abstract
In the preparation of the bata drums of Cuba and Yorubaland, ritual specialists affix a small iron ring near the smaller of the two heads of these drums. The ring is the material marker that the drums are consecrated, imbued with the power of Ayan, the orisha of drumming. This study looks to other appearances of iron rings and iron idiophones along sub-Saharan trade routes connected to the Oyo Empire, the ‘source’ of bata drumming. The study links the use of rings in these regions to iconic sites of Yoruba culture in the Americas—Brazil and Cuba—as a means of revisiting some of the dominant narratives in the constructed past of orisha worship on both sides of the Atlantic, before and after the transatlantic separation. The prominence given to the Oyo-Shango complex in American forms of orisha worship is considered here to be unwarranted.
Growing Up to Save the World: Christ and the Fantasies of Boyhood
Authors: Saxena Vandana 
Published: February 2013

Abstract
This paper explores the intricate link between the story of Christ and the contemporary constructions of adolescence boyhood through a careful study of J.K. Rowling’s Harry Potter series. Though the success of the series can be seen in terms of the general trend of the resurfacing of religion in the current world order, the paper argues that the series attempts to revise and reconfigure the scriptural narrative by integrating the themes of boyhood and bringing in contemporary cultural and secular concerns. The story of boy-to-man transition echoes the story of Christ: his life, the temptations, the ordeals, and ultimately the sacrifice and resurrection. Linked with discourses of adolescent angst and defiance, the scriptural story acquires a potential for active political and social intervention.
Impact of prior CKD management in a renal care network on early outcomes in incident dialysis patients: a prospective observational study
Authors: Rognant Nicolas , Alamartine Eric , Aldigier Jean Claude , Combe Christian , Vendrely Benoit , Deteix Patrice , Cluzel Pascal , Juillard Laurent , Vrtovsnik François , Maurice Christelle , Fave Sophie , Laville Maurice 
Published: February 2013

Abstract

Background
Effective therapeutic strategies are available to prevent adverse outcomes in patients with chronic kidney disease (CKD) but their clinical results are hindered by unplanned implementation. Coordination of care emerges as a suitable way to improve patient outcomes. In this study, we evaluated the effect of planned and coordinated patient management within a dedicated renal care network comparatively to standard renal care delivered in nephrology departments of teaching hospitals.

Methods
This observational matched cohort study included 40 patients with CKD stage 4–5 in the network group as compared with a control group of 120 patients matched for age, sex and diabetic status. Main outcome was a composite endpoint of death from cardiovascular cause and cardiovascular events during the first year after dialysis initiation.

Results
There was no difference between the two groups neither for the primary outcome (40% vs 41%) nor for the occurrence of death from cardiovascular cause or cardiovascular events. Whereas the proportion of patients requiring at least one hospitalization was identical (83.3% vs 75%), network patients experienced less individual hospitalizations than control patients (2.3±2.0 vs 1.6±1.7) during the year before dialysis start. Patients of the network group had a slower renal function decline (7.7±2.5 vs 4.9±1.1 ml/min/1,73m2 per year; p=0.04).

Conclusions
In this limited series of patients, we were unable to demonstrate a significant impact of the coordinated renal care provided in the network on early cardiovascular events in incident dialysis patients. However, during the predialysis period, there were less hospitalizations and a slower slope of renal function decrease.
Impact of acute kidney injury exposure period among liver transplantation patients
Authors: Narciso Roberto Camargo , Ferraz Leonardo Rolim , Mies Sergio , Monte Julio Cesar Martins , dos Santos Oscar Fernando Pavão , Neto Miguel Cendoroglo , Rodrigues Cassio José de Oliveira , Batista Marcelo Costa , Junior Marcelino Souza Durão 
Published: February 2013

Abstract

Background
Acute kidney injury is a common complication of liver transplantation. In this single-centre retrospective observational study, we investigated the impact of acute kidney disease on liver recipient survival.

Methods
The study population consisted of patients who underwent a liver engraftment between January 2002 and November 2006, at a single transplantation centre in São Paulo, Brazil. Acute kidney injury diagnosis and staging were according to the recommendations of the Acute Kidney Injury Network and consisted of scanning the daily serum creatinine levels throughout the hospital stay. Patients requiring renal replacement therapy prior to transplantation, those who developed acute kidney injury before the procedure or those receiving their second liver graft were excluded from the study.

Results
A total of 444 liver transplantations were performed during the study period, and 129 procedures (29%) were excluded. The remaining 315 patients constituted the study population. In 207 procedures, the recipient was male (65%). The mean age of the population was 51 years. Cumulative incidence of acute kidney injury within 48 h, during the first week after transplantation, and throughout the hospital stay was 32, 81 and 93%, respectively. Renal replacement therapy was required within a week after the transplantation in 31 procedures (10%), and another 17 (5%) required replacement therapy after that period. Mean follow-up period was 2.3 years. Time in days from acute kidney injury diagnosis to initiation of replacement therapy or reaching serum creatinine peak was associated with lower overall survival even when adjusted for significant potential confounders (HR 1.03; 95% CI 1.01, 1.05; p=0.002). Overall, patients experiencing acute kidney injury lasting for a week or more before initiation of replacement therapy experienced a threefold increase in risk of death (HR 3.02; 95% CI 2.04, 4.46; p<0.001).

Conclusions
Acute kidney injury after liver transplantation is remarkably frequent and has a substantial impact on patient survival. Delaying the initiation of renal replacement therapy in such population may increase mortality by more than 20% per day.
Visibility enhancement using an image filtering approach
Authors: Zhang Yong-Qin , Ding Yu , Xiao Jin-Sheng , Liu Jiaying , Guo Zongming 
Published: February 2013

Abstract
The misty, foggy, or hazy weather conditions lead to image color distortion and reduce the resolution and the contrast of the observed object in outdoor scene acquisition. In order to detect and remove haze, this article proposes a novel effective algorithm for visibility enhancement from a single gray or color image. Since it can be considered that the haze mainly concentrates in one component of the multilayer image, the haze-free image is reconstructed through haze layer estimation based on the image filtering approach using both low-rank technique and the overlap averaging scheme. By using parallel analysis with Monte Carlo simulation from the coarse atmospheric veil by the median filter, the refined smooth haze layer is acquired with both less texture and retaining depth changes. With the dark channel prior, the normalized transmission coefficient is calculated to restore fogless image. Experimental results show that the proposed algorithm is a simpler and efficient method for clarity improvement and contrast enhancement from a single foggy image. Moreover, it can be comparable with the state-of-the-art methods, and even has better results than them.
Sentinel node in ovarian cancer: study protocol for a phase 1 study
Authors: Kleppe Marjolein , Van Gorp Toon , Slangen Brigitte FM , Kruse Arnold J , Brans Boudewijn , Pooters Ivo NA , Van de Vijver Koen K , Kruitwagen Roy FPM 
Published: February 2013

AbstractBackgroundThe concept of sentinel lymph node surgery is to determine whether the cancer has spread to the very first lymph node or sentinel node. If the sentinel node does not contain cancer, then there is a high likelihood that the cancer has not spread to other lymph nodes. The sentinel node technique has been proven to be effective in different types of cancer. In this study we want to determine whether a sentinel node procedure in patients with ovarian cancer is feasible when the tracers are injected into the ovarian ligaments.Methods/DesignPatients with a high likelihood of having an ovarian malignancy in whom a median laparotomy and a frozen section analysis is planned and patients with endometrial cancer in whom a staging laparotomy is planned will be included.Before starting the surgical staging procedure, blue dye and radioactive colloid will be injected into the ligamentum ovarii proprium and the ligamentum infundibulo-pelvicum. In the analysis we calculate the percentage of patients in whom it is feasible to identify sentinel nodes. Other study parameters are the anatomical localization of the sentinel node(s) and the incidence of false negative lymph nodes.Trial registrationApproval number: NL40323.068.12Name: Medical Ethical Committee Maastricht University Hospital, University of MaastrichtAffiliation: Maastricht University HospitalBoard Chair Name: Medisch Ethische Commissie azM/UM
Optical properties and Limits of a Large-Area Periodic Nanophotonic Light Trapping Design for Polycrystalline Silicon Thin Film Solar Cells
Authors: Lockau Daniel , Sontheimer Tobias , Preidel Veit , Becker Christiane , Ruske Florian , Schmidt Frank , Rech Bernd 
Published: February 2013

ABSTRACTRigorous finite element optical simulations have been used to examine the absorption of light in various crystalline silicon based, nanostructured solar cell architectures. The compared structures can all be produced on glass substrates using a periodically structured dielectric coating and a combination of electron-beam evaporation of silicon and subsequent solid phase crystallization. A required post-treatment by selective etching of non-compact silicon regions results in an absorber material loss. We show that by adequately tailoring the optical design around the processed silicon layer, the absorptance loss due to material removal can be completely overcome. The resulting silicon structure, which is an array of holes with non-vertical sidewalls, shows promising light path enhancement and features an even higher absorptance than the initial nanodome structure of the unetched absorber.
Temperature Dependence of Electrical Characterization in n+ - CdS/ p - CdTe Thin Film Solar Cells – Study of Shallow/Deep Defects
Authors: Kharangarh Poonam Rani , Georgiou George E , Chin Ken K 
Published: February 2013

ABSTRACTFor CdTe there is no real distinction between defects and impurities exists when non-shallow dopants are used. These dopants act as beneficial impurities or detrimental carrier trapping centers. Unlike Si, the common assumption that the trap energy level Et is around the middle of the band-gap Ei, is not valid for thin film CdTe. Trap energy levels in CdTe band-gap can distributed with wide range of energy levels above EF. To identify the real role of traps and dopants that limit the solar cell efficiency, a series of samples were investigated in thin film n+-CdS/p-CdTe solar cell, made with evaporated Cu as a primary back contact. It is well known that process temperatures and defect distribution are highly related. This work investigates these shallow level impurities by using temperature dependent current-voltage (I-V-T) and temperature dependent capacitance-voltage (C-V-T) measurements. I-V-T and C-V-T measurements indicate that a large concentration of defects is located in the depletion region. It further suggests that while modest amounts of Cu enhance the cell performance by improving the back contact to CdTe, the high temperature (greater than ∼100°C) process condition degrade device quality and reduce the solar cell efficiency. This is possibly because of the well-established Cu diffusion from the back contact into CdTe. Hence, measurements were performed at lower temperatures (T = 150K to 350K). The observed traps are due to the thermal ionization of impurity centers located in the depletion region of p-CdTe/n+-CdS junction. For our n+-CdS/p-CdTe thin film solar cells, hole traps were observed that are verified by both the measurement techniques. These levels are identical to the observed trap levels by other characterization techniques.
Micromechanical testing of oxidized grain boundaries in Nickel alloys from nuclear reactors
Authors: Lozano-Perez Sergio , Dugdale Helen , Armstrong David E J , Terachi Takumi , Yamada Takuyo , Tarleton Edmund , Roberts Steve G 
Published: February 2013

ABSTRACTThe fracture behaviour of individual grain boundaries has been studied in order to understand the mechanisms controlling stress corrosion cracking in nuclear reactors. In particular, the role of oxidation in facilitating crack initiation and propagation has been reviewed. Nickel alloys from pressurized water reactors (PWRs) have been tested in simulated primary water conditions to induce grain boundary oxidation. Microcantilevers containing an oxidized grain boundary plane have been prepared and tested for fracture. The brittle nature of the oxide was demonstrated and the required stress to fracture measured.
B Diffusion in Low Energy B/BF2 Implants with Pre-Amorphization of Different Species
Authors: Li Hong-Jyh , Rhoad Todd , Zeitzoff Peter , Tichy Robin , Larson Larry , Banerjee Sanjay 
Published: February 2013

AbstractThe formation of an amorphous layer is needed to prevent channeling effect of B in the subsequent implant and hence, shallower as-implanted and annealed profiles could be expected. B diffusion in the pre-amorphization (PAI) Si has been studied extensively by many research groups and the diffusion has been explained by the interaction of B and defects generated by the PAI and B implant processes. In our previous study, we found that B diffusion can also be affected by the immobile B clustering caused by the incorporated species and therefore, B diffusion in the PAI Si should be expected to be different with different PAI species due to their different effect on the B clustering. In this paper, we reported different B diffusion behavior in bulk Si with respective to different PAI species. The species include GeF2, Ge, F, BF2, and In and the immobile B clustering plays an important role in the B diffusion reduction.
Atomistic Simulations of Effect of Coulombic Interactions on Carrier Fluctuations in Doped Silicon
Authors: Qin Zudian , Dunham Scott T. 
Published: February 2013

AbstractCarrier distributions associated with point charges in silicon solved with quantum perturbation theory are used to determine Coulombic interactions between charged defects in the presence of carrier screening. The resulting interactions are used in kinetic lattice Monte Carlo (KLMC) simulations of point defect-mediated diffusion to study dopant redistribution and associated variations in carrier concentration. Over a broad range of doping concentrations and temperatures, Coulombic repulsion between like dopants leads to ordering, resulting in a more uniform electrical potential distribution and therefore reduced variations in device performance compared with random doping, the standard condition assumed in previous doping fluctuation analyses.
Dopant Diffusion Simulation in Thin-SOI
Authors: Li Hong-Jyh , Tichy Robin , Ross Jonathon , Gelpey Jeff , Stotts Ben , Galloway Heather 
Published: February 2013

AbstractAs the top Si layer is thinned, the dopants' diffusion in the confined Si layer in SOI wafer with respect to different thermal treatments needs to be better understood. Boron, BF2 with/without Ge pre-amorphization were implanted into bulk Si and SOI wafers with 530 Å Si and 1475A BOX. Samples were annealed using both spike (Impulse) anneal and Flash anneal. Simulations of dopant diffusion is used to resolve apparent differences in dopant profiles that resulted for SOI in contrast with bulk Si samples. Result suggests that the implantation damage difference between SOI and bulk Si makes the B diffusion in SOI higher than in bulk Si.
Indium in silicon: a study on diffusion and electrical activation.
Authors: Scalese S. , Magna A. La , Mannino G. , Privitera V. , Bersani M. , Giubertoni D. , Solmi S. , Pichler P. 
Published: February 2013

AbstractIn this work we investigate the diffusion and the electrical activation of In atoms implanted in silicon with different energies, in the range 80-360 keV, after rapid thermal processing. Our investigation shows a clear dependence of In out-diffusion and electrical activation on the implant depth, being the electrically active fraction higher with increasing the implant energy for a fixed dose. The data are explained considering the balance between the local In concentration and the C background inside the silicon substrate and the formation of C-In complexes, which play a role in the enhanced electrical activation due to the shallower level they introduce into the Si band gap (Ev+0.111 eV), with respect to the rather deep level (Ev+0.156 eV) of In alone. In and C co-implantation has also been studied within this work, in order to confirm the key role of C in the increase of the electrical activation. A large increase of the electrical activation has been detected in the co-implanted samples, up to a factor of about 8 after annealing at 900°C. However, C precipitation occurs at 1100°C, with dramatic effects on the carrier concentration.
Silicides for 65 nm CMOS and Beyond
Authors: Kittl Jorge A. , Lauwers Anne , Chamirian Oxana , Dal Mark Van , Akheyar Amal , Richard Olivier , Lisoni Judit G. , Potter Muriel De , Lindsay Richard , Maex Karen 
Published: February 2013

AbstractAn overview of silicide development for the 65 nm node and beyond is presented. The scaling behavior of Co based and Ni based silicides to sub-100 nm junctions and sub-40 nm gate lengths was investigated. Co and Co-Ni silicides required a high thermal budget to achieve low diode leakage. Even for lower thermal budgets, the sheet resistance of Co and Co-Ni silicides increased at gate lengths below 40 nm. NiSi had low sheet resistance down to 30 nm gate lengths exhibiting a reverse linewidth effect (sheet resistance decreased with decreasing linewidth), achieved lower contact resistivity than CoSi2 and lower diode leakage for similar sheet resistance values. Bridging issues cannot be ignored for NiSi, in particular for thicker Ni films, higher RTP temperatures and in the presence of Ti. Material issues for the application of NiSi were also investigated. Ni2Si was found to grow with diffusion limited kinetics in the 225-300°C range, with an activation energy of 1.5 eV. Results of the kinetic studies were used to design a two-step RTP process that limited the silicide thickness on small features by a low thermal budget first RTP step, reducing the reverse linewidth effect and avoiding excessive silicidation. In the presence of an interfacial oxide, undesired epitaxial NiSi2 pyramidal grains grew directly at temperatures as low as 310°C on p+ Si. Thermal stability of NiSi was also investigated. We found that the initial mechanism of degradation for thin NiSi films was agglomeration, with activation energies of 2.5-3 eV. The surface after agglomeration remained quite flat with alternating NiSi and exposed Si areas, while the interface roughened significantly. Thick films also degraded initially by agglomeration at low temperatures, but by transformation to NiSi2 at higher temperatures. The addition of Pt improved thermal stability of NiSi films against agglomeration. The Ni/Si-Ge reaction was also studied, finding that the addition of Ge reduced the thermal process window and resulted in a slightly higher resistivity.
Recursive Partitioning Analysis for the Prediction of Stereotactic Radiosurgery Brain Metastases Lesion Control
Authors: Rodrigues George , Zindler Jaap , Warner Andrew , Lagerwaard Frank 
Published: February 2013

Abstract

Learning Objectives
Describe the results of a new recursive partitioning analysis (RPA) predicting for SRS lesion control. Discuss the SRS lesion in the light of other literature assessing predictors of lesion control in SRS for brain metastases.

Purpose.
The objective of this investigation was to identify independent pretreatment factors that predict for control of local brain metastases (BM) in a large single-institution series of patients receiving stereotactic radiosurgery (SRS). Recursive partitioning analysis was used to potentially identify a class of patients with durable lesion control characteristics.

Methods.
A retrospective SRS database containing baseline characteristics, treatment details, and follow-up data of newly diagnosed patients with 1–3 BM (on magnetic resonance imaging) treated with linear accelerator-based SRS was created. Three study endpoints were used: time to progression (primary endpoint, individual lesion progression; n = 536), time to first progression (secondary endpoint, first lesion progression on an individual patient basis; n = 380), and overall survival (secondary endpoint; n = 380). Recursive partitioning analysis (RPA) was performed to identify predictors of time to progression.

Results.
Multivariable analysis demonstrated that lesion aspect/phenotype and radiotherapy schedule were independent factors associated with both progression outcomes. Presence of tumor necrosis was found to be associated with a significant hazard of progression (hazard ratio &gt;3), whereas use of the most intense radiotherapy fractionation schedule (21 Gy in one fraction) was associated with significant reductions in progression (hazard ratio &lt;0.3). RPA using SRS dose and lesion aspect/phenotype was created and described three distinct prognostic groups.

Conclusions.
RPA of a large retrospective database of patients receiving SRS confirmed previous observations regarding the importance of SRS dose and lesion aspect/phenotype in lesion control and overall survival. The SRS lesion analysis may help to stratify future clinical trials and better define patient care options and prognosis.