bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical treatment of degenerate diffusion equations via Feller's boundary classification, and applications
Authors: Cacio Emanuela , Cohn Stephen E. , Spigler Renato 
Published: February 2011

AbstractA numerical method is devised to solve a class of linear boundary‐value problems for one‐dimensional parabolic equations degenerate at the boundaries. Feller theory, which classifies the nature of the boundary points, is used to decide whether boundary conditions are needed to ensure uniqueness, and, if so, which ones they are. The algorithm is based on a suitable preconditioned implicit finite‐difference scheme, grid, and treatment of the boundary data. Second‐order accuracy, unconditional stability, and unconditional convergence of solutions of the finite‐difference scheme to a constant as the time‐step index tends to infinity are further properties of the method. Several examples, pertaining to financial mathematics, physics, and genetics, are presented for the purpose of illustration. © 2011 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2011
A cost effectiveness analysis of thiopurine methyltransferase testing for guiding 6‐mercaptopurine dosing in children with acute lymphoblastic leukemia
Authors: Donnan Jennifer R. , Ungar Wendy J. , Mathews Maria , Hancock‐Howard Rebecca L. , Rahman Proton 
Published: February 2011

AbstractBackgroundAn increased understanding of the genetic basis of disease creates a demand for personalized medicine and more genetic testing for diagnosis and treatment. The objective was to assess the incremental cost‐effectiveness per life‐month gained of thiopurine methyltransferase (TPMT) genotyping to guide doses of 6‐mercaptopurine (6‐MP) in children with acute lymphoblastic leukemia (ALL) compared to enzymatic testing and standard weight‐based dosing.ProcedureA cost‐effectiveness analysis was conducted from a health care system perspective comparing costs and consequences over 3 months. Decision analysis was used to evaluate the impact of TPMT tests on preventing myelosuppression and improving survival in ALL patients receiving 6‐MP. Direct medical costs included laboratory tests, medications, physician services, pharmacy and inpatient care. Probabilities were derived from published evidence. Survival was measured in life‐months. The robustness of the results to variable uncertainty was tested in one‐way sensitivity analyses. Probabilistic sensitivity analysis examined the impact of parameter uncertainty and generated confidence intervals around point estimates.ResultsNeither of the testing interventions showed a benefit in survival compared to weight‐based dosing. Both test strategies were more costly compared to weight‐based dosing. Incremental costs per child (95% confidence interval) were $277 ($112, $442) and $298 ($392, $421) for the genotyping and phenotyping strategies, respectively, compared to weight‐based dosing.ConclusionsThe present analysis suggests that screening for TPMT mutations using either genotype or enzymatic laboratory tests prior to the administration of 6‐MP in pediatric ALL patients is not cost‐effective. Pediatr Blood Cancer 2011; 57: 231–239. © 2011 Wiley‐Liss, Inc.
Multivariate analysis of the relation between immune dysfunction and treatment intensity in children with acute lymphoblastic leukemia
Authors: Ek Torben , Josefson Mats , Abrahamsson Jonas 
Published: February 2011

AbstractBackgroundImmunoreconstitution following childhood acute lymphoblastic leukemia (ALL) is a complex process during which various immune functions recover differentially. This process is difficult to elucidate since variables are interrelated and require simultaneous evaluation, rendering conventional statistical methods inappropriate.ProcedureWe used principal components analysis (PCA) and projection of latent structures (PLS) to evaluate immune competence in 32 children treated for ALL. One or 6 months after completion of therapy, the relation between lymphocyte subpopulations, lymphocyte function and response to vaccination with tetanus, diphtheria and hemophilus influenzae, was investigated.ResultsPCA demonstrated that increasing treatment intensity correlated with progressive immune dysfunction. Children treated with high intensity had poor response to vaccination associated with loss of humoral memory, decreased CD4+45RA+ T‐lymphocytes and increased CD5+ B‐lymphocytes. Patients treated with intermediate intensity had better preservation of humoral memory but decreased CD4+45RA+ T‐cells. Patients with a low intensity regimen had similar vaccination response and lymphocyte levels as controls.ConclusionsOur findings demonstrate the utility of PCA and PLS in detecting hidden structures in complex data and suggest that, even 6 months after therapy, patients treated with intermediate and high intensity have attenuated responses to de novo antigens whereas those with high intensity also respond poorly to recall antigens. Pediatr Blood Cancer 2011;56:1078–1087. © 2011 Wiley‐Liss, Inc.
The effect of a sodium octacosanoate‐based nucleating agent on the crystallization of thermoplastic polyurethanes
Authors: Freitag C.P.M. , Riegel I.C. , Pezzin S.H. , Costa M.L. , Amico S.C. 
Published: February 2011

AbstractSodium octacosanoate (NaC28‐32) is commonly used as a nucleating agent in polyester and polyamide formulations. In this work, the effect of adding this agent to three chemically identical thermoplastic polyurethanes (TPUs), but with distinct molecular weights, was addressed, focusing on the study of the crystallization phenomenon. The modified Avrami and Avrami‐Ozawa kinetic models were applied to the isothermal and non‐isothermal crystallization processes, respectively, and both indicated faster crystallization when the nucleating agent was used, with an increase in temperature and rate of crystallization of the TPU. Such effect was partly attributed to the formation of a larger number of crystallization nuclei in comparison to the neat TPU. Besides, the nucleating effect was more pronounced for the TPU with the lowest molecular weight (30,000 Dalton). The Avrami and Avrami‐Ozawa models indicated that the TPU crystallization process occurs with the development of two‐dimensional lamellar aggregates, axialites, and that the incorporation of thenucleating agent does not alter this geometry. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Replication characterization in injection molding of microfeatures with high aspect ratio: Influence of layout and shape factor
Authors: Yang Can , Huang Han‐Xiong , Castro Jose M. , Yi Allen Y. 
Published: February 2011

AbstractIn this work, both experimental study and numerical simulation were carried out to investigate the replication capability and flow behavior of polymeric melt inside microchannels with high aspect ratio. For this purpose, a mold insert with microchannels having different layouts (parallel and transverse to the main flow direction) and various cross sectional shapes (triangle, rectangle, and semicircle) was designed and fabricated. The filled length and surface morphology of the microfeatures molded under different conditions were characterized using scanning electron microscope and optical microscope. It was found that the cross sectional shape had clear influence on the filled length of the microfeatures, with a dependence on the mold layout. Moreover, serious hesitation of polymeric flows in microchannels took place in the transverse layout, which led to eccentric line defects. However, such defects were not observed in the parallel layout. At last, the specific mechanisms of how the cross sectional shape affected the replication capability and how the line defects in the microfeatures' surface formed were discussed. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Measurement and simulation of vibrations of PV‐modules induced by dynamic mechanical loads
Authors: Assmus Marcus , Jack Steffen , Weiss Karl‐Anders , Koehl Michael 
Published: February 2011

AbstractThe dynamic behavior of PV‐modules is analyzed by different methods. Outdoor measurements of the deflection show their dynamic behavior under wind loads and the correlation between wind velocity and mechanical deflection. Indoor tests were performed with acoustic excitation of the modules with monitoring of the deflection. The frequency range of the resonance frequencies of different modules was between 10 and 100 Hz. Numerical calculations, based on FEM‐modeling, yielded a very good agreement with the experimental results. Copyright © 2011 John Wiley & Sons, Ltd.
Study of the effect of excess carrier lifetime depth profiles and depth dependent absorption coefficients on the emitted photoluminescence spectrum of chalcopyrite thin films
Authors: Knabe S. , Langemeyer M. , Heidemann F. , Brüggemann R. , Bauer G. H. 
Published: February 2011

ABSTRACTThe emitted photoluminescence (PL) resulting from radiative recombination in semiconductors is strongly governed by excess carrier density, which is influenced by excess carrier lifetime, absorption coefficient and according boundary conditions at front and rear contact. We have numerically solved the diffusion equation for the excess carrier density with depth dependent lifetime profiles (originating from a depth dependent defect density) and depth dependent absorption coefficient (originating from a depth dependent band‐gap) using a residual control based boundary value problem solver. The emitted PL from the absorber has been calculated on the basis of the excess carrier density with a 1D‐matrix transfer formalism including propagation, multireflection at phase boundaries and reabsorption of PL‐photons. For different lifetime or absorption depth profiles we have characterized the influence on the excess carrier depth profile as well as on the resulting spectral PL yield. Finally the calculated PL spectra were compared to the quasi‐Fermi level splitting from the excess carriers to show the influence of both depth profiles on the shape of the photoluminescence spectrum. Copyright © 2010 John Wiley & Sons, Ltd.
Ray tracing for the optics at nano‐textured ZnO–air and ZnO–silicon interfaces
Authors: Schulte Melanie , Bittkau Karsten , Pieters Bart Elger , Jorke Silvia , Stiebig Helmut , Hüpkes Jürgen , Rau Uwe 
Published: February 2011

AbstractWe investigate the scattering behavior of nano‐textured ZnO–Air and ZnO–Silicon interfaces for the application in thin film silicon solar cells. Contrary to the common approach, the numerical solution of the Maxwell's equations, we introduce a ray tracing approach based on geometric optics and the measured interface topography. The validity of this model is discussed by means of scanning near‐field optical microscopy (SNOM) measurements and numerical solutions of the Maxwell's equations. We show, that the ray tracing model can qualitatively describe the formation of micro lenses, which are the dominant feature of the local scattering properties of the investigated interfaces. A quantitative analysis for the ZnO–Silicon interface at λ = 488 and 780 nm shows that the ray tracing model corresponds well to the numerical solution of the Maxwell's equations, especially within the first 1.5 µm distance from the interface. Direct correlations between the locally scattered intensity and the interface topographies are found. Copyright © 2011 John Wiley & Sons, Ltd.
Thirty Years of Geographical (In)consistency in the British Population Census: Steps towards the Harmonisation of Small‐Area Census Geography
Authors: Walford Nigel S. , Hayles Kelly N. 
Published: February 2011

ABSTRACTThe existence of digital boundary data files to accompany area census statistics for small units has now become accepted as the norm in respect of population census output in many countries. However, there has been growing variation in the specification of census geography and widespread inconsistency in the sets of polygons between the constituent countries of the UK. This paper reports on research that has created data sets of consistent areas and estimates of census counts spanning the last four British censuses from 1971 to 2001 to enable the comparison of small spatial units and the analysis of population change. The paper assesses the data sets produced by areal weighting and dasymetric mapping by comparison with a subset of consistent spatial units between 1981 and 1991 and with published statistics for larger areas. The results are also examined in relation to previously published methods of obtaining weights empirically for use in the dasymetric mapping. The paper highlights the potential of the consistent small spatial units that have been created for the analysis of population change over time. Copyright © 2011 John Wiley & Sons, Ltd.
On the role of the metal‐to‐ligand charge transfer states in the light‐induced spin crossover in FeII (bpy)3
Authors: Graaf Coen De , Sousa Carmen 
Published: February 2011

AbstractThe light‐induced spin crossover in FeII complexes is studied with complete active space second‐order perturbation theory. The potential energy surfaces of the low‐spin and high‐spin states are determined as function of the Fe‐‐ligand distance interpolating between the high‐spin and low‐spin equilibrium geometries. In addition, we calculate the relative energies of the lowest excited
${\rm Fe}-3{\rm d}^6$
states along this coordinate. To address the mechanism of spin crossover, the metal‐to‐ligand charge transfer states with singlet, triplet, and quintet spin coupling were also treated. The curves of the singlet and triplet MLCT states nearly coincide, but the quintet MLCT curve is higher in energy and the equilibrium distance displaced to larger distances. The possible deactivation mechanisms of the 1MLCT state are discussed considering the relative energies and spin‐orbit coupling matrix elements of the relevant electronic states. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem 111:3385–3393, 2011
The quantile method for symbolic principal component analysis
Authors: Ichino Manabu 
Published: February 2011

AbstractIn this article, we present a new quantification method to realize the principal component analysis (PCA) for symbolic data tables. We first describe the nesting property for the monotone point sequences and the correlation matrix by the rank correlation coefficient. Then, we present the object splitting method by which interval valued data table can be transformed to a usual numerical data table. We are able to apply the traditional PCA to this transformed data table. The quantile method is a generalization of the object splitting method, and can manipulate histograms, nominal multi‐value types, and other types simultaneously. We present several experimental results in order to illustrate the usefulness of the quantile method. © 2011 Wiley Periodicals, Inc. Statistical Analysis and Data Mining 4: 184–198, 2011
Peripheral DNA damage in active pulmonary tuberculosis
Authors: Selek Sahbettin , Aslan Mehmet , Horoz Mehmet , Celik Hakim , Cosar Niyet , Gunak Faruk , Kocyigit Abdurrahim 
Published: February 2011

AbstractIn pulmonary tuberculosis patients, little is known about peripheral DNA damage, although increased oxidative stress is a well documented entity. Therefore, we aimed to investigate DNA damage along with oxidative status parameters in pulmonary tuberculosis patients. Twenty‐seven pulmonary tuberculosis patients and 26 controls were included. DNA damage was assessed by comet assay. Total oxidant and antioxidant status, and oxidative stress index were determined. DNA damage, total oxidant status and oxidative stress index were higher in pulmonary tuberculosis patients than controls (all P < 0.05), while total antioxidant status was lower (P < 0.05). DNA damage was correlated with total oxidant and antioxidant status, and oxidative stress index (r = 0.69, P < 0.05; r = 0.48, P < 0.05, r = −0.47, P < 0.05; respectively) in pulmonary tuberculosis patients. Oxidative stress and DNA damage are increased in pulmonary tuberculosis patients. Increased oxidative stress associated DNA damage may be one of the pathogenetic mechanisms involved in the disorders suggested to be associated with pulmonary tuberculosis. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2012.
On restoring of the pre‐stressed state in elastic bodies
Authors: Dudarev V.V. , Vatulyan A.O. 
Published: February 2011

AbstractThis research is devoted to the development of theoretical foundations for identification of an essentially inhomogeneous prestressed state by analyzing the gain‐frequency characteristic of boundary points of the body. The proposed scheme to the reconstruction of inhomogeneous prestresses is constructed on the iterative processes. It includes the finite element solution of the direct problem and the regularizing procedure to solve the Fredholm integral equation of the first kind in the inverse problem. In the series of one‐dimensional model examples it was shown that this scheme is effective.
Surgeon‐patient barrier efficiency monitored with an electronic device in three surgical settings
Authors: Hentz Vincent R. , Stephanides Michael , Boraldi Attilio , Tessari Renato , Isani Riccardo , Cadossi Ruggero , Biscione Roberto , Massari Leo , Traina GianCarlo 
Published: February 2011

AbstractBlood‐borne viral pathogens are an occupational threat to health care workers (HCWs), particularly those in the operating room. A major risk is posed by accidental penetrating injury, but skin contamination with body fluids from an infected patient, with prolonged intimate cutaneous contact, is a frequent occurrence during surgery, carrying further risk of transdermal infection. We have monitored barrier failure in three surgical settings (microsurgery, orthopedic surgery, general surgery) by means of an electronic surveillance device. A total of 111 surgical procedures were monitored: 67 microsurgeries, 22 orthopedic surgeries, and 22 general surgeries. Of the 278 electronic alarms signaling barrier failure, 44 (15.8%) were associated with glove perforation, 39 of which (88.6%) were not perceived by the operator. In 16 of those, the skin was visibly stained with the patient’s blood. Altogether, 76 of the alarms (27.3%) were consequent to contacts caused by soaked gowns/sleeves, and 121 (43.5%) were attributed to hydration of latex porosities; 37 alarms (13.4%) were unexplained false positives. On only one occasion did a surgeon observe blood stains on his hands without a previous alarm; this event was classified as a device failure due to incorrect wiring. Doublegloving offered satisfactory protection against skin contamination during microsurgery but not during orthopedic surgery. The data presented here indicate that electronic monitoring of the surgical barrier enables prompt detection of barrier failure, especially at the level of the gloves, thereby limiting skin contamination with patients’ body fluids during surgery.
Mycotic aneurysm of common carotid artery induced byStaphylococcus bureus infection after cervical reoperation
Authors: Machens Andreas , Dralle Henning 
Published: February 2011

AbstractThe objective of this study was to define a novel type of mycotic aneurysm of the carotid artery arising after cervical reoperation. We retrospectively analyzed all staphylococcal mycotic aneurysms of the common carotid artery. These aneurysms had developed after reoperative thyroid or parathyroid surgery, including resection of the central lymph node compartment and cervical reexploration. Mycotic aneurysms were found in three patients, with an incidence of 0.77% (2/261) and 0.62% (1/161) for thyroid and parathyroid reoperations, respectively. Postoperatively, a lymphatic fistula and cervical hematoma emerged in all patients, as did cervical wound infections on days 3, 4, and 6. Deep wound infections were noted on surgical revision. Cultures grew exclusivelyStaphylococcus aureus, which was resistant to methicillin (MRSA) in one patient. Mycotic aneurysms were identified 1 week after cervical reoperation. One aneurysm was discovered incidentally on planned lavage. The other two aneurysms presented as severe arterial hemorrhages, resulting in exsanguination in one patient. The other two patients had their aneurysms replaced by saphenous venous autografts. There seems to be accelerated arterial media destruction with formation of mycotic aneurysms in staphylococcal wound infections after cervical reoperation. It is important to recognize this novel type of mycotic aneurysm, as it must be repaired immediately to anticipate imminent rupture.
Prognostic significance of synchronous and metachronous bilateral breast cancer
Authors: Kollias James , Ellis Ian O. , Elston Christopher W. , Blamey Roger W. 
Published: February 2011

AbstractWomen previously treated for primary operable breast cancer are at increased risk of developing cancer in the contralateral breast, but the clinical significance of this development is unclear. The purpose of this study was to assess the impact of synchronous bilateral breast cancer or the development of a metachronous contralateral breast primary on the prognosis. In a series of 3210 women age ≤70 years treated between 1975 and 1995 for primary operable breast cancer, 106 were identified to have bilateral breast cancer. Of these women, 26 were noted to have synchronous bilateral breast primaries (0.8%), and 80 developed a contralateral breast cancer after treatment for an initial primary breast cancer. Using life‐tables analysis, there was a significant difference in survival between women with unilateral breast cancer, those with synchronous bilateral breast cancers, and those with metachronous contralateral breast with survivals at 16 years of 53.8%, 42.4%, and 60.1%, respectively (p<0.0001), from the date of the diagnosis of the first primary tumor. There was no difference in survival seen between the three groups when survival was calculated from the date of diagnosis of the second primary in cases of metachronous contralateral breast cancer (p=0.31). When contralateral breast cancer was incorporated as a time‐dependent covariate in a Cox multivariate model together with the three factors used to determine the Nottingham Prognostic Index (invasive tumor size, grade, and lymph node stage), contralateral breast cancer continued to be a significant prognostic determinant (p=0.02). The survival of women with synchronous bilateral breast cancer or metachronous breast cancers diagnosed within 2 years of the original primary was worse than those with unilateral disease. However, the time duration to metachronous contralateral breast cancer did not have prognostic significance in a multivariate model compared with the prognostic features of the original primary.