bluuebunny/crossref_metadata_2025_split huggingface dataset:
An adaptive wavelet solver for a nonlinear parameter identification problem
for a parabolic differential equation with sparsity constraints
Authors: Dahlke Stephan , Friedrich Ulrich , Maass Peter , Raasch Thorsten , Ressel Rudolf A. 
Published: March 2012

Abstract.
In this paper, we combine concepts from two different mathematical research topics: adaptive wavelet techniques for well-posed problems and regularization theory for nonlinear inverse problems with sparsity constraints. We are concerned with identifying certain parameters in a parabolic reaction-diffusion equation from measured data. Analytical properties of the related parameter-to-state operator are summarized, which justify the application of an iterated soft shrinkage algorithm for minimizing a Tikhonov functional with sparsity constraints. The forward problem is treated by means of a new adaptive wavelet algorithm which is based on tensor wavelets.
In its general form, the underlying PDE describes gene concentrations in embryos at an early state of development. We implemented an algorithm for the related nonlinear parameter identification problem and
numerical results are presented for a simplified test equation.
Creation of Face-to-face π-π Stacking of Fused Acene Backbones by Aryl-perfluoroaryl Interactions and Induction of Charge Transport Properties
Authors: Okamoto Toshihiro , Nakahara Katsumasa , Saeki Akinori , Seki Shu , Oh Joon H. , Akkerman Hylke B. , Bao Zhenan , Miwa Kazumoto , Takeya Junichi , Matsuo Yutaka 
Published: March 2012

ABSTRACTThe charge transport properties critically depend on the degree of ordering of the chains in the solid state as well as on the density of chemical or structural defects. In general, goodelectronic performance requires strong electronic coupling between adjace nt molecules in the solid-state that yield strong intermolecular π-overlap. Herein, we newly designed and synthesized organic semiconducting materials having both aryl (Ar) and perfluoroaryl (FAr) as substituents for organic electronics along with molecular packing control. Regarding this molecular design, we hypothesized and expected that the Ar and FAr substituents would induce well-defined π-π stacking structure of charge transport units for high performance organic electronics devices.
Mechanisms of Oxidation of Fuel Cladding Alloys Revealed by High Resolution APT, TEM and SIMS Analysis
Authors: Grovenor Chris R. M. , Ni Na , Hudson Daniel , Yardley Sean S. , Moore Katie L. , Smith George D. W. , Lozano-Perez Sergio , Sykes John M. 
Published: March 2012

ABSTRACTAqueous corrosion of zirconium alloys has become the major factor limiting prolonged fuel campaigns in nuclear plant. Studies using SEM, TEM and electrochemical impedance measurements have been interpreted as showing a dense inner-most oxide layer, and an increased thickness of the layer has been correlated to a better corrosion resistance. Many authors have reported that an ‘intermediate layer’ at the metal oxide interface has a complex structure or/and stochiometry different to that of both the bulk oxide and bulk metal, sometimes claimed to be a suboxide phase. Diffraction evidence has suggested the presence of both cubic ZrO and rhombohedral Zr3O phases, and compositional analysis has revealed similar variations in local oxygen stoichiometry.We have carried out a systematic investigation of the structure and chemistry of the metal/oxide interface in samples of commercial ZIRLO corroded for times up to 180 days. We have developed new experimental techniques for the study of these interfaces both by Electron Energy Loss Spectroscopy (EELS) analysis in the Transmission Electron Microscope (TEM) and by Atom Probe Tomography (APT), and exactly the same samples have been investigated by both techniques. Our results show the development of a clearly defined suboxide layer of stoichiometry close to ZrO, and the subsequent disappearance of this layer at the first of the characteristic ‘breakaway’ transitions in the oxidation kinetics. We can correlate this behaviour with changes in the structure of the oxide layer, and particularly the development of interconnected porosity that links the corroding interface with the aqueous environment. Using high resolution SIMS analysis of isotopically spiked samples we demonstrate the penetration of the oxidising species through these porous outer oxide layers.
Face to face with enemy – analysis of aqua carbonate hydroxide second surface phases in proton conducting perovskite ceramic electrolytic membrane.
Authors: Slodczyk Aneta , Tran Caroline , Colomban Philippe 
Published: March 2012

ABSTRACTThe various perovskite ceramic electrolytic membranes, (Ba,Sr)(Zr,Ce,Nb,In,Sn)O3 modified by incorporation of Ln/RE elements, are widely investigated due to their high industrial potential for H2 production and CO2 conversion. One of the most important criteria to classify such ceramic as a good membrane is its high mechanical and chemical stability over thousands hours in severe operating conditions: high temperature and (high water) vapour pressure cycling. It is well known that the Ba- and Sr-based materials can easily form the mixed carbonates, hydroxides, hydrates, hydroxycarbonates, … The presence of undesirable phases, even limited to traces, on the ceramic surface, and/or at the grain boundary, may lead directly to the premature degradation. Since such mixed, hydrated, poorly crystallized phases cannot be detected by diffraction experiments, we have performed thermogravimetric analysis as well as IR and Raman spectroscopic study. The comparison of vibrational and TGA signatures characteristic of complex secondary phases i.e. (Sr/ Ba)(OH)x(CO3)y, nH2O and of proton conducting perovskite reveals that the ignorance of a second phase presence can lead to wrong conclusion concerning the bulk proton nature and understanding of associated conductivity mechanisms.
Fabrication of Graphene Network via Nanoimprint Lithography
Authors: Zou Liumin , Konishi Keita , Hoga Morihisa , Yoh Kanji 
Published: March 2012

ABSTRACTWe have investigated the hexagonal graphene network (GNW) structure for the possible opening of the graphene bandgap. We have fabricated GNW by nanoimprint lithography and compared with previous GNW results based on electron beam (EB) lithography. Hall-bar device with GNW was successfully fabricated using nanoimprint lithography and verified mobility of 1,220 cm2 V-1 s-1 with graphene nanoribbon (GNR) width of 40 nm. The mobility improvement compared with GNW by EB lithography indicates the effectiveness of nanoimprint method for the hexagonal GNW approach.
CVD-Graphene Complementary Logic on Ultra-thin Multilayer Hexagonal Boron Nitride
Authors: Kim Edwin , Jain Nikhil , Xu Yang , Han Yan , Yu Bin 
Published: March 2012

ABSTRACTGraphene, a two-dimensional carbon allotrope, has raised great interests as a material candidate for future electronics due to its superb carrier transport and unique physics. The demand for future-generation large-scale carbon-based electronics motivates assembly of large-area graphene and selection of ideal substrate material that best preserves the transport property of graphene. In this work, CVD-assembled large-area graphene on thin multilayer hexagonal boron nitride (h-BN) is employed to demonstrate the basic building block of digital circuit - inverter prototype made of two graphene-channel field-effect transistors (GFETs). The doping in the CVD-grown graphene, probed via electrical measurements, is implemented through non-uniform local surface chemistry. The full transfer response of the graphene logic inverter is demonstrated in the localized P/N doping region.
Fabrication of Complex Hydrogel Materials by Utilizing Microfluidics and Micromolding
Authors: Yamada Masumi , Sugaya Sari , Kobayashi Aoi , Miyama Ayaki , Naganuma Yoji , Yamada Emi , Kakegawa Shunta , Seki Minoru 
Published: March 2012

ABSTRACTHere, we present microfluidic methods to fabricate complex hydrogel structures for 3D tissue or organ-like cell structures in vitro. First, a microfluidic system to continuously synthesize chemically and physically anisotropic Ca–alginate hydrogel microfibers is proposed to enable the guidance of cell proliferation and differentiation. Next, the microfluidic preparation methods for yarn-ball-shape hydrogel particles and extremely-small hydrogel microspheres. Finally, a newly developed micro-molding and bonding method for hydrogel micro-patterned plates is reported.
Nanomodified Endotracheal Tubes: Spatial Analysis of Reduced Bacterial Colonization in a Bench Top Airway Model
Authors: Machado Mary C. , Tarquinio Keiko M. , Webster Thomas J. 
Published: March 2012

ABSTRACTVentilator associated pneumonia (VAP) is a serious and costly clinical problem. Specifically, receiving mechanical ventilation for over 24 hours increases the risk of VAP and is associated with high morbidity, mortality and medical costs. Cost effective endotracheal tubes (ETTs) that are resistant to bacterial infection could help prevent this problem. The objective of this study was to determine differences in the growth ofStaphylococcus aureus(S. aureus) on nanomodified and unmodified polyvinyl chloride (PVC) ETTs under dynamic airway conditions. PVC ETTs were modified to have nanometer surface features by soaking them inRhizopus arrhisus,a fungal lipase. Twenty-four hour experiments (supported by computational models) showed that air flow conditions within the ETT influenced both the location and concentration of bacterial growth on the ETTs especially within areas of tube curvature. More importantly, experiments revealed a 1.5 log reduction in the total number ofS. aureuson the novel nanomodified ETTs compared to the conventional ETTs after 24 hours of air flow. This dynamic study showed that lipase etching can create nano-rough surface features on PVC ETTs that suppressS. aureusgrowth and, thus, may provide clinicians with an effective and inexpensive tool to combat VAP.
Improvement of Adhesive Strength of Polyacetal by Irradiation of Vacuum Ultra-Violet Light and Deposition of Nanometer-Sized Particles Simultaneously using Laser Ablation
Authors: Takeichi Akihiro , Okamoto Yasushi , Azuma Hirozumi 
Published: March 2012

ABSTRACTPolyacetal is a resin which has excellent property. However, polyacetal has a poor adherence property using adhesive material. Therefore, for the improvement of the adhesive strength, simultaneous surface treatments of polyacetal by irradiation of vacuum ultra-violet (VUV) light and deposition of nanometer-sized particles using laser ablation with C, Si and Ti targets were carried out. The surface treatments were carried out with different wavelengths, energies, processing times and substrate locations from normal direction of targets. The targets were irradiated with a pulsed laser from Nd-YAG laser. After surface treatments, tensile test pieces of polyacetal were bonded by epoxide-based adhesive. And, longitudinal shear strengths were measured. As a result, after surface treatment of polyacetal using C target, the highest shear bond strength which is approximately 8 times larger than that of untreated polyacetal sample was measured (5.6 MPa). It was found that increasing functional groups and increasing surface roughness are affecting improvement of the adhesive strength. The improvement of the adhesive strength is also caused by the new-creation of the dangling-bonds on the polymer surface by VUV irradiation and preservation of each dangling-bonds from re-bonding each other by a separation effect of deposited nanometer-sized particles. This method can be expected for new applications of polymers.
Shape Memory Behavior of Ultra-High Molecular Weight Polyethylene
Authors: Kaloshkin Sergey , Maksimkin Aleksey , Kaloshkina Maria , Zadorozhnyy Mihail , Churyukanova Margarita 
Published: March 2012

ABSTRACTShape memory effect in pure ultra-high molecular weight polyethylene (UHMWPE) has been studied using dynamic mechanical analysis. Temperature dependencies of properties that define functional characteristics of shape memory polymers (SMP) such as recovery stress, recovery strain and activation temperature of transition were determined for UHMWPE. The recovery stress in UHMWPE deformed by 200% achieved rather high values, up to 7 MPa.
Understanding MOCVD Gas Chemistry to Reduce the Cost of Ownership for GaN LED and AsP CPV Technologies
Authors: Armour E.A. , Mitrovic B. , Zhang A. , Ebert C. , Pophristic M. , Paranjpe A. 
Published: March 2012

ABSTRACTAs compound semiconductors continue to make inroads into common electronic devices, it is critically important to lower the cost of the primary metal-organic chemical vapor deposition (MOCVD) epitaxial process, which creates the foundation for the devices. Both GaN-based light-emitting diode (LED) and AsP-based concentrator photovoltaic (CPV) markets have been focused on simultaneous cost-reduction, cycle time reductions, and device efficiency improvements, which can be realized utilizing higher growth rates and operating pressures. To achieve these goals, it has become increasingly important to understand the underlying growth mechanisms that drive the chemistry within the MOCVD process.Higher growth rates and higher operating pressures both result in parasitic gas-phase particle formation, which degrades the physical, electrical and optical properties of the deposited layers. In extreme cases, it can reduce the deposition efficiency to the point where increasing the reactant constituents results in reduced growth rates. In this paper, we will examine the tradeoffs that need to be made to achieve good crystal quality with abrupt interfaces, smooth surface morphology, and good minority carrier properties for films deposited at high growth rates and high pressure. While exceptional device performance has been achieved for both GaN-based LEDs and AsP-based CPV cells, it is primarily cost that is limiting full-scale adoption of compound semiconductors into these potentially enormous markets.
Long‐term experimental loss of foundation species: consequences for dynamics at ecotones across heterogeneous landscapes
Authors: Peters Debra P. C. , Yao J 
Published: March 2012

Biome transition zones where species co‐exist near their geographic limits are expected to be among the most responsive to changes in climate that result in mortality of foundation species. Long‐term (>13 years) patterns in dominance and cover of functional types were examined following the annual experimental removal of one of three foundation species at an arid‐semiarid biome transition zone. Objectives were to identify key processes influencing these patterns, and to predict future landscape‐scale dynamics following mortality of different foundation species. Aboveground biomass of dominant species was removed from 3 × 4 m plots. Cover by species on control and removal plots was estimated annually in communities with a single dominant species, and in ecotonal communities with two dominant species across two types of ecotones (semiarid grassland‐arid grassland, arid grassland‐arid shrubland).For most species and functional types, trends in cover through time were related to the remaining species assemblages rather than to variable climatic conditions. In ecotonal communities, resident co‐dominant species increased to dominance following the loss of a foundation species with little change in community composition. In mono‐dominated communities, dominant species loss resulted in a shift to species that are currently sub‐dominants of the same functional type as the species that was removed. Subdominant perennial grass and shrub species increased rapidly following removals in most grassland locations. Annuals and perennial forbs had variable cover values through time that were not clearly related to pulses in precipitation and were not synchronized across locations. The most common response regardless of the identity of the foundation species removed or the community type was an increase in cover by sub‐dominant grasses and by the arid grass species (Bouteloua eriopoda). The rate of increase by B. eriopoda depended on initial cover, and resulted from both vegetative growth and seedling recruitment from other locations. Seed dispersal and seedling recruitment from other locations were not found for the semiarid grass, Bouteloua gracilis or the arid shrub, Larrea tridentata. Because B. eriopoda is more susceptible to shrub invasion, drought, and livestock grazing than the other two foundation species, widespread loss of either of the other species and subsequent increase in B. eriopoda is expected to result in an increase in landscape‐scale vulnerability to these environmental drivers. The extent and magnitude of this change in vulnerability will depend on the ability of B. eriopoda to respond based on the micro‐environmental conditions of the site regardless of which species (B. gracilis, L. tridentata) is lost.
Multiple Thoracic Hydatidosis: A Case Report
Authors: Mlika Mona , Ayadi-Kaddour Aida , El Mezni Faouzi 
Published: March 2012

Background:
Multiple thoracic hydatidosis is uncommon even in endemic countries.
Case Presentation: A 37-year-old Caucasian man came to our observation with a 10-day history of basi-thoracic chest
pain and dyspnea. Chest X-ray showed a well limited cardiac opacity associated to an opacity of the upper lobe of the
right lung. Chest CT-scan showed a mediastinal cyst evoking a hydatid cyst in the left ventricle associated to a right
pleural effusion. The patient underwent surgery that consisted in the drainage of multiple pericardial cysts, cystectomy of
a left ventricle cyst and right pleural cystectomy. Microscopic examination showed a pleuro-pulmonary and cardiopericardial
hydatidosis. The patient was treated with albendazole and did not present complications or recurrences after
one year of follow up.

Conclusion:

Multiple thoracic hydatidosis is rare. Cardiac location is most challenging because it is difficult to manage
and life threatening. Treatment modalities continue to be based mainly on surgery. Preventive measures are necessary to
avoid disease recurrence.
Validation of Microcapillary Flow Cytometry for Community-Based CD4+ T Lymphocyte Enumeration in Remote Burkina Faso
Authors: Renault Cybèle A , Traore Arouna , Machekano Rhoderick N , Israelski Dennis M 
Published: March 2012

BackgroundCD4+ T lymphocyte enumeration plays a critical role in the initiation and monitoring of HIV-infected patients on antiretroviral therapy. There is an urgent need for low-cost CD4+ enumeration technologies, particularly for use in dry, dusty climates characteristic of many small cities in Sub-Saharan AfricaDesignCross-sectional studyMethodsBlood samples from 98 HIV-infected patients followed in a community HIV clinic in Ouahigouya, Burkina Faso were obtained for routine CD4+ T lymphocyte count monitoring. The blood samples were divided into two aliquots, on which parallel CD4+ measurements were performed using microcapillary (Guava EasyCD4) and dedicated (Becton Dickinson FACSCount) CD4+ enumeration systems. Spearman rank correlation coefficient was calculated, and the sensitivity, specificity and positive predictive value (PPV) for EasyCD4 <200 cells/µL were determined compared to the reference standard FACSCount CD4 <200 cells/µLResultsMean CD4 counts for the EasyCD4 and FACSCount were 313.75 cells/µL and 303.47 cells/µL, respectively. The Spearman rank correlation coefficient was 0.92 (p<0.001). Median values using EasyCD4 were higher than those with the FACSCount (p=0.004). For a CD4<350 cells/uL, sensitivity of the EasyCD4 was 93.9% (95%CI 85.2-98.3%), specificity was 90.6% (95% CI 75.0-98.0%), and PPV was 95.4% (95%CI 87.1-99.0%)ConclusionUse of the EasyCD4 system was feasible and highly accurate in the harsh conditions of this remote city in Sub-Saharan Africa, demonstrating acceptable sensitivity and specificity compared to a standard operating system. Microcapillary flow cytometry offers a cost-effective alternative for community-based, point-of-care CD4+ testing and could play a substantial role in scaling up HIV care in remote, resource-limited settings
Cholesterol Synthesis, Cholesterol Absorption, and Mortality in Hemodialysis Patients
Authors: Rogacev Kyrill S. , Pinsdorf Tobias , Weingärtner Oliver , Gerhart Markus K. , Welzel Elena , van Bentum Kai , Popp Julius , Menzner Andreas , Fliser Danilo , Lütjohann Dieter , Heine Gunnar H. 
Published: March 2012

Summary

Background and objectives
Recent clinical trials on cholesterol-lowering in patients with CKD yielded conflicting results, which might have resulted from different treatment strategies. Serum cholesterol levels are determined by endogenous synthesis and intestinal absorption, which are differentially influenced by various classes of cholesterol-lowering agents. Assessing markers of cholesterol metabolism has thus been proposed for guidance of lipid-lowering therapy. This study analyzed surrogate markers of cholesterol absorption and synthesis in hemodialysis (HD) patients.

Design, setting, participants, & measurements
In 113 HD patients, lathosterol was measured as a marker of cholesterol synthesis and cholestanol was measured as a marker of cholesterol absorption via gas chromatography. Controls were 229 healthy persons. Overall survival in HD patients was recorded over 3.4-year follow-up.

Results
Compared with controls, HD patients had lower lathosterol and higher cholestanol levels (P<0.001 for both). During follow-up, 58 patients died; higher cholestanol (indicating higher cholesterol absorption) predicted poor outcome among HD patients in multivariate Cox regression analysis after adjustment for potential confounders (hazard ratio for cholestanol above median, 2.24 [95% confidence interval (CI), 1.29–3.89]; P=0.004), whereas lower lathosterol (indicating lower cholesterol synthesis) did not (hazard ratio for lathosterol below median, 1.43 [95% CI, 0.81–2.50]; P=0.22).

Conclusions
This analysis of markers of cholesterol metabolism characterizes HD patients as cholesterol absorbers. In longitudinal analysis, higher levels of cholestanol were associated with all-cause mortality.
Antibodies against Linear Epitopes on the Goodpasture Autoantigen and Kidney Injury
Authors: Jia Xiao-yu , Cui Zhao , Yang Rui , Hu Shui-yi , Zhao Ming-hui 
Published: March 2012

Summary

Background and objectives
Linear epitopes on the Goodpasture autoantigen involved in human anti-glomerular basement membrane (GBM) disease are not fully defined. This study investigated the linear epitopes recognized by circulating antibodies in anti-GBM patients, aiming to identify the potential nephrogenic linear epitopes and their clinical significance.

Design, setting, participants, & measurements
Sixty-eight patients with anti-GBM disease were enrolled. Twenty-four overlapping linear peptides were synthesized across the whole sequence of the human Goodpasture autoantigen. ELISA detected circulating antibodies against linear epitopes. Their associations with clinical features were further analyzed.

Results
Antibodies against linear peptides were detected in sera from 55 patients (80.9%). Three major epitopes with high frequencies were identified: P14 (41%), P16 (36.8%), and P18 (57%). P14, a formerly defined T cell epitope, was a mutual B cell epitope. Antibodies against P14 were frequently detected in patients with positive antineutrophil cytoplasmic antibodies (39.3% versus 12.5%; P=0.01). Patients with anti-P16 antibodies presented with higher serum creatinine on diagnosis (665.5±227.2 versus 443.7±296.8 μmol/L; P=0.001) and worse renal outcome during follow-up (hazard ratio, 2.10; 95% confidence interval, 1.10–3.90; P=0.02). The level of anti-P18 antibodies positively correlated with the percentage of crescents in glomeruli (r=0.54; P=0.008). Recognition of P22 was an independent predictor for patient death (hazard ratio, 3.02; 95% confidence interval, 1.20–7.57; P=0.02).

Conclusions
Antibodies against linear epitopes on the Goodpasture autoantigen could be detected in human anti-GBM disease and were associated with kidney injury. P14 was a mutual T and B cell epitope, implying its nephrogenic role in disease initiation.