bluuebunny/crossref_metadata_2025_split huggingface dataset:
Density Functional Theory Calculations of Properties of the Grain Boundaries in Aluminum
Authors: Muzyk Marek , Kurzydlowski Krzysztof J. 
Published: April 2011

ABSTRACTThe Density Functional Theory has been used to analyze an inter-granular segregation of Cu and Mg. The stability of Cu and Mg atoms in the aluminum matrix, intermetallic phases and symmetric twist grain boundaries has been compared. The quantitative description of solubility of Cu and Mg atoms in the nano-crystalline aluminum has been proposed. The calculations have been carried out to investigate the properties of symmetric twist boundaries in aluminum with and without Cu/Mg atoms. The phenomena of are discussed and its effect on the stability of precipitates containing these elements.
From lignin to spruce: Poromechanical upscaling of wood
strength
Authors: Bader Thomas K. , Hofstetter K. , Hellmich Ch. , Eberhardsteiner Josef 
Published: April 2011

ABSTRACTWood strength is highly anisotropic, due to the inherent structural
hierarchy of the material. In the framework of a combined random-periodic
multiscale poro-micromechanics model, we here translate compositional
information throughout this hierarchy into the resulting anisotropic
strength at the softwood level, based on “universal” elastic properties of
cellulose, hemicelluloses, and lignin, and on the shear strength of the
latter elementary constituent. Therefore, derivation of the elastic energy
in a piece (representative volume element – RVE) of softwood, stemming from
homogeneous macroscopic strains prescribed in terms of displacements at the
boundary of the RVE and from pressure exerted by water filling the
nanoporous space between the hemicelluloses-lignin network within the cell
walls, with respect to the shear stiffness of lignin, yields higher order
strains in the lignin phase, approximating micro-stress peaks leading to
local lignin failure. Relating this (quasi-brittle) failure to overall
softwood failure (or strictly speaking, elastic limit of softwood) results
in a macroscopic microstructure-dependent failure criterion for softwood.
The latter satisfactorily predicts the biaxial strength of spruce at various
loading angles with respect to the grain direction. The model also predicts
the experimentally well-established fact that uniaxial tensile and
compressive strengths, as well as the shear strength of wood, depend
quasi-linearly on the cell water content, but highly nonlinearly on the
lumen porosity.
Porous Scaffolds Consisting of Collagen, Chondroitin Sulfate,
and Hydroxyapatite with Enhanced Biodegradable Resistance for Cartilage
Regeneration
Authors: Kaneda H. , Ikoma T. , Yoshioka T. , Nishi M. , Matsumoto R. , Uemura T. , Cross J. S. , Tanaka J. 
Published: April 2011

ABSTRACTPorous scaffolds of alkaline-soluble collagen including nanocomposite
particles of chondroitin sulfate and low crystalline hydroxyapatite for
cartilage regeneration were fabricated by freeze-drying and thermal
dehydration treatments; porous collagen scaffolds were also synthesized as a
reference. The scaffolds were cross-linked using glutaraldehyde (GA) vapor
treatment in order to enhance biodegradable resistance. Microstructural
observation with scanning electron microscope indicated that the scaffolds
with and without GA cross-linkage had open pores between 130 to 200 μm in
diameter and well-interconnected pores of 10 to 30 μm even after
cross-linkage. In vitro biodegradable resistance to
collagenase was significantly enhanced by GA cross-linking of the scaffolds.
All these results suggest that the GA cross-linked scaffolds consisting of
collagen, chondroitin sulfate, and low crystalline hydroxyapatite have
suitable microporous structures and long-term biochemical stability for
cartilage tissue engineering.
Atomistic Study of Helium Bubbles in Fe: Equilibrium State
Authors: Stewart David M. , Osetskiy Yury N. , Stoller Roger E. 
Published: April 2011

ABSTRACTIn the fusion irradiation environment, helium created by transmutation will play an important role in the response of structural materials to neutron radiation damage. Recently we have developed a new 3-body potential to describe the Fe–He interaction in an Fe matrix. We have used this potential to investigate the equilibrium state of He bubbles embedded into the bcc Fe matrix. We have investigated bubble size, He content and temperature effects. It was found that the equilibrium He content is rather low and at a room temperature it is ~0.38 to 0.5 He per vacancy for bubble diameters from 1 to 6 nm. At constant bubble size, the equilibrium He/vacancy ratio decreases with temperature increase. For bubbles of 6 nm diameter it goes down as low as ~0.25 at 900K. The results are compared with the capillarity model often used for estimating the equilibrium pressure of He bubbles.
Phase State and Physical Properties of the Mo-Ru-Ph-Pd Alloys
Authors: Sugahara Tohru , Kurosaki Ken , Yusufu Aikebaier , Muta Hiroaki , Ohishi Yuji , Yamanaka Shinsuke , Komamine Satoshi , Ochi Eiji 
Published: April 2011

ABSTRACTMo3Ru5MPd (M = Ru, Rh, Pd) as the simulated materials for the undissolved residue in the nuclear fuel reprocessing were prepared by arc melting method. The physical properties and oxidation behavior of the alloys were evaluated from viewpoint of the safety and economy in the reprocessing. The electrical resistivity, ρ, of Mo3Ru5RhPd was shown to be 0.8 μΩm at room temperature. On the other hand, the ρ values of samples without Rh were marked at 0.4 μΩm. The thermal properties of the each sample had the different thermal transfer characteristics. In particular, although the thermal conductivities of Mo3Ru5RhPd and Mo3Ru5Pd2 samples show almost the same value, the lattice thermal conductivities of both samples showed different values. Oxidation behavior was analyzed using the thermogravity(TG) and differential thermal analyses(DTA). The TG curve of each sample by oxidation showed different results. These results indicate that the simulated materials of the alloys without Rh: Mo-Ru-Pd were not appropriate to simulate the thermophysical characteristics of the typical simulated materials with undissolved residue Mo-Ru-Rh-Pd alloys. Therefore, in the spent nuclear fuel reprocessing, the mock test of reprocessing without to use Rh is difficult to carry out.
The Effect of Microwave Radiation on Tensile Properties of
Silkworm (B. mori) Silk
Authors: Reed Emily J. , Viney Christopher 
Published: April 2011

ABSTRACTWe have developed a reproducible protocol for studying the effect of
microwave radiation on the mechanical behavior of Bombyx
mori cocoon silk. In the course of this work, we identified
multiple improvements that can be made to ASTM F 1317-98, the standard
according to which microwave oven power output is calibrated.Exposure to microwaves does not significantly affect mechanical properties
of silkworm silk, if samples are kept in a desiccator after degumming (or
after degumming and microwaving) and prior to testing in a dry environment.
This finding contrasts with previous work in which samples were not kept in
a desiccator, and were tested in a relatively humid environment.Because the effect of microwave radiation on the mechanical behavior of silk
is sensitive to ambient moisture, meaningful comparison or pooling of test
results acquired in different laboratories is contingent on standardization
of both the sample storage environment and the environment in which samples
are tested. Interpretation of the extensive existing literature on silk
mechanical properties must take account of the reality that the sample
storage and testing environments are not standardized and are usually not
reported.
Influence of Processing Conditions on Mechanical and Structural Properties of DLC Produced by FIB-CVD Method
Authors: Sakamoto Naomichi , Akita Yusai , Harada Hiroyuki , Yasuno Takuya , Kogo Yasuo 
Published: April 2011

ABSTRACTInfluence of processing condition on mechanical and structural properties of diamond-like carbon (DLC) by focused ion-beam chemical vapor deposition (FIB-CVD) method was investigated. The DLC specimens were produced under conditions of varying supplied amount of material gas and probe current of FIB. Volume determination results of DLC structures indicated that a deposition rate was increased with both the amount of gas and the probe current. To evaluation of mechanical property, indentation hardness was measured by a nano-indentation tester. From evaluation of mechanical property, it was found that the indentation hardness was sensitive to the processing condition, showing in the range of 8-13 GPa. The hardness of DLC structures was seemed to be lower when etching process higher contributed for formation process. Crystallographic structure of DLC remained amorphous even though the mechanical properties varied widely. Results of hydrogen concentration measurement indicated that increase of hydrogen concentration might lead to decrease of hardness.
Plasmon induced modifications of the Förster energy transfer in
reconstituted peridinin-chlorophyll-protein photosynthetic
complex
Authors: Schmidt Mikolaj K. , Govorov Alexander O. , Mackowski Sebastian 
Published: April 2011

ABSTRACTIn this work we investigate theoretically the effects imposed by plasmon
excitations in spherical metallic nanoparticles (MNPs) on the rate of energy
transfer in peridinin-chlorophyll-protein (PCP) complex reconstituted with
both chlorophyll a (Chl a) and chlorophyll
b (Chl b). This light-harvesting
complex is unique since it features efficient energy transfer both from
higher-lying Chl b to lower-lying Chl a as
well as in the opposite, less energy-favorable direction. The results of
calculations show that the Förster energy transfer rate decreases with a
MNP-PCP distance changing from 2 to 144nm, while the energy
transfer from Chl a to Chl b remains less
efficient at all distances. We conclude that plasmon excitations allow for
controlling the energy transfer between Chls, as well as the excitation
distribution between two spectrally distinguishable Chls within the
reconstituted PCP complex.
Insurance, Consumer Choice, and the Equilibrium Price and Quality of Hospital Care
Authors: Katz Michael L 
Published: April 2011

Abstract
I analyze price and quality competition in a model that captures important institutional features of U.S. hospital markets. I first consider duopoly hospitals serving a population of patients who are covered by insurance that their employers purchase from duopoly health plans. I show that second-best quality levels can be sustained as equilibrium outcomes under both indemnity insurance and managed care even when patients are fully insured. I also demonstrate that a monopoly hospital system can yield efficient quality levels and that prices may be lower under monopoly than duopoly even when there are no technical efficiencies associated with monopoly. The latter result arises when employers and health insurance plans view the hospitals as complements even though any given consumer views them as substitutes.
The Upgrade of Hereditary Cancer Surveillance Schedule by Valka District Population Screening Data
Authors: Vanags Andrejs , Strumfa Ilze , Gardovskis Andris , Melbarde-Gorkusa Inga , Abolins Arnis , Trofimovics Genadijs , Gardovskis Janis 
Published: April 2011

The Upgrade of Hereditary Cancer Surveillance Schedule by Valka District Population Screening Data
Introduction. The concept of hereditary cancer is one of the most important achievements in modern oncology. It has major scientific implications as well as high practical value in surveillance, prevention and adjustment of treatment for hereditary and familial malignancies. Identification of the persons-at-risk allows recommending a follow-up schedule for timely diagnostics of the corresponding cancers. Aim of the Study is to evaluate the need for hereditary cancer surveillance program in Latvia and to adjust the surveillance schedule by population screening data. Materials and methods. The study was performed as population screening in the Valka district, evaluating the family cancer history of 18642 respondents. Hereditary cancers were diagnosed by internationally accepted clinical criteria. Descriptive statistical analysis was carried out by CIA software. Results. There were 885 persons, fulfilling the clinical diagnostic criteria of hereditary and familial cancer syndromes. The full spectrum of hereditary malignancies was identified thus indirectly characterising the familial background of oncological diseases in the local population. The cancer burden among blood relatives was high for all syndromes, exceeding 8.6%. The mean age of cancer diagnostics was significantly different among the syndromes, ranging 38.0-72.0 years. Conclusions. The presence of familial background in all most frequent cancer locations and the high cancer burden in the affected kindreds justify the need for familial cancer surveillance. The data about the age of cancer manifestation can be used to adjust the follow-up schedule for most syndromes. Specific recommendations are elaborated and described in the article.
Apolipoprotein A1 and Transferrin as Biomarkers in Ovarian Cancer Diagnostics
Authors: Macuks Ronalds , Baidekalna Ieva , Gritcina Julia , Avdejeva Arina , Donina Simona 
Published: April 2011

Apolipoprotein A1 and Transferrin as Biomarkers in Ovarian Cancer Diagnostics
Introduction. Advanced technologies such as matrix assisted laser desorption/ionization and surface enhanced laser desorption/ionization mass spectrometry has introduced promising insights into ovarian cancer detection. Several highly sensitive and specific protein peaks have been identified that discriminates ovarian cancer patients from patients with benign ovarian tumors and controls. Aim of the Study. Objective of this study is to evaluate diagnostic accuracy each individual marker and combined serum biomarker assay consisting of apolipoprotein A1, transferrin and Ca125. Materials and methods. A case-control study consisted of 99 women - 37 patients with ovarian cancer, 31 patients with benign ovarian diseases, and 31 age-matched healthy controls. Apolipoprotein A1 and transferrin was measured in sera using immunological turbidimetric assay. Tumor marker CA125 was analyzed by standard enzyme-labeled chemiluminescent immunometric assay. To compare the difference between variables in the study groups, ANOVA test was performed and for correlation Pearson's correlation analysis applied. Sensitivity and specificity of the diagnostic tests was calculated using statistical program Vassarstat. Results. Serum apolipoprotein A1 and transferrin were down regulated, controversially to Ca125, which was up regulated among ovarian cancer patients. Negative correlation between transferrin and Ca 125 (p<0.00), apolipoprotein A1 and Ca 125 (p<0.00) and positive correlation between transferrin and apolipoprotein A1 (p<0.00) was observed. For single biomarker test highest diagnostic sensitivity and specificity for Ca125 was observed. Addition of apolipoprotein A1 or transferrin to serum level of Ca125 with the condition, that both have to overlap the threshold (Ca125 > 21U/ml and apolipoprotein A1 ≤ 139.1 mg/dl or transferrin ≤ 2.3 g/l), yielded test specificity of 96.7%. Addition of apolipoprotein A1 to Ca125 improved test sensitivity up to 94.5% maintaining high sensitivity at the same time 91.1%, respectively, when discriminating controls from ovarian cancer patients. Biomarker test consisting of apolipoprotein A1, transferrin and Ca125 had high specificity at unacceptable sensitivity. Conclusions. Combined biomarker tests discovered using advanced technologies can aid more accurate ovarian cancer detection. Use of apolipoprotein A1 in combination with Ca125 at distinct thresholds can improve ovarian cancer detection.
Predicting Fetal Prognosis by Assessing Fetal and Maternal Blood Flow Patterns in Pregnancies with Fetal Growth Restriction
Authors: Vedmedovska Natalija , Rezeberga Dace , Teibe Uldis , Donders Gilbert 
Published: April 2011

Predicting Fetal Prognosis by Assessing Fetal and Maternal Blood Flow Patterns in Pregnancies with Fetal Growth Restriction
Introduction. Fetal growth restriction (FGR) is associated with prematurity and a number of complications, as well as long-term impact on metabolic or cardiac function in adults. Aim of the Study. To study the prognostic value of staging maternal and fetal Doppler blood flow velocities in women with FGR; and evaluate prenatal characteristics as possible risk factors for severe vascular abnormalities. Materials and methods. 70 singleton pregnancies complicated by FGR were included in prospective follow-up study. Blood flow velocities in the uterine (UtA), umbilical (AU), middle cerebral (ACM) arteries and ductus venosus (DV) were measured. FGR neonates grouped as follows: I) normal blood velocity waveforms; II) abnormal UtA velocimetry and/or presence of early diastolic "notch"; III) abnormal AU without signs of "brain sparing"; IV) abnormal AU and ACM pulsatility index (PI) and V) AU absent or reversed end diastolic flow and an abnormal DV. Prenatal risk factors and perinatal outcome were assessed in relation to these Doppler blood flow patterns and compared with Fisher exact and Pearson c2 test. Results. There was a strong correlation between the severity of grouping and birth weight (p<0.001), gestational age at delivery (p<0.001), low amniotic fluid index (p<0.001), low Apgar scores (p=0.01) and neonatal transfer rate to NICU or hospital (p=0.02). Groups IV and V fetuses had the highest perinatal mortality (p=0.01). Women having genital infections (RTI) had significantly worse Doppler flow profile than non-smoking women at term without RTI (p=0.02). Conclusions. Severity of blood flow redistribution correlates with fetal morbidity and mortality. Less severe vascular changes, such as abnormal AU flow without centralization, and even increased uterine artery PI alone are linked to reduced birth weight, higher likelihood of preterm birth and increased risk of morbidity. Genital infections contribute significantly to hemodynamic changes related to the FGR. Screening and preventing of STI as well as optimizing the time of delivery may improve the overall outcome of compromised fetuses.
The Evaluation of Early Results after Total Hip Replacement in Dysplastic Hip Patients
Authors: Zebolds Silvestris , Jumtins Andris 
Published: April 2011

The Evaluation of Early Results after Total Hip Replacement in Dysplastic Hip Patients
Introduction. Dysplasia of hip joint leads to osteoarthritis. Suffer relatively young population in ages between 20 and 40. Due to severe changes of anatomy total hip replacement (THR) in dysplastic hip patients is a challenge for orthopaedic surgeons. Radical anatomical and biomechanical reconstruction may lead to high complication rate. The planning of the rotation center of hip joint is a key of success in the treatment of dysplastic osteoarthritis patients. Aim of the Study. The aim of the study was to evaluate the early results for dysplastic osteoarthritis patients (DOA), who underwent THR in Riga State Hospital of Traumatology and Orthopaedics in 2008-2009. Materials and methods. 63 THR were performed in 59 patients (50 women, 9 men). In all cases cementless acetabular components of endoprosthesis were used. Functional evaluation was made due to method of grading functional value of hip - Merle d'Aubigne and Postel. Hip dysplasia was divided in 4 groups due to classification after Crowe. Special digital orthopaedic programmes (AGFA, IMPAX) were used for preoperative planning and radiographic postoperative analysis. Results. Regarding to method of grading functional value of hip - Merle d'Aubigne and Postel we found out a significant improvement in range of movements, mobility and pain relief. Due to Crowe classification there were 19 patients with Crowe type I dysplasia, 29 with Crowe type II and 15 with Crowe type III. 43 acetabular cups were placed in the primary socket and 20 in the secondary socket. Radiographic analysis showed significant changes in location of rotation center of hip and offset after THR in dysplastic hip patients. Conclusions. Significant functional improvement was achieved after THR in DOA patients and the radiographic analysis showed significant decrease of horizontal location of RC and increase of offset after THR in DOA patients.
Immunohistochemical Study of Choledochal Cyst Wall
Authors: Ozolina Linda , Pilmane Mara , Engelis Arnis 
Published: April 2011

Immunohistochemical Study of Choledochal Cyst Wall
Introduction. Choledochal cysts are rare congenital anomalies that appear as localized cystic or fusiform biliary tree dilatations. Choledochal cyst is a rare congenital anomaly with a reported incidence of 1 in 100,000-150,000 live births (7). Nearly 25% of choledochal cysts are diagnosed in the first year of life and 60% in the first decade, but 20% detected are after the age of 20 years (12). Aim of the Study. The pathogenesis of choledochal cysts remains still unknown. The aim of this study was to examine relative distribution of growth factors, neuropeptide-containing innervation and apoptosis in the choledochal cyst wall. Materials and methods. Histopathological study of choledochal cyst wall was conducted on four patients aging from six months till 14 years. Tissues were processed for haematoxylin - eosin staining, immunohistochemistry for PGP 9.5, NGFR, NF, VEGF, CGRP and TUNEL method. Results. In overview sections we observed granulation tissue, blood vessel sanguineness and inflammatory infiltrate. Fibromuscular coat was thickened showing thick collagen bundles and dispersed smooth myocytes. Serosa was present in one case, all the rest demonstrated adhesions with dilated blood vessels and perivascular infiltrate. PGP 9.5 - containing nerve fibers and nerve fiber bundles were mostly observed in moderate and large amounts. NGFR in large amount was seen in nerve fiber bundles and nerve fibers among smooth muscle cells in the wall of small blood vessels. NF positive structures - nerve fibers and nerve fiber bundles - were found in moderate amount, except one case were the expression was very low. CGRP was found in neuroendocrine cells, nerve fiber bundles, leukocytes, inflammatory cells and endoteliocytes. Expression varied from low to moderately high. VEGF expression in most patient material was negative. Apoptosis was observed in inflammatory cells and epiteliocytes, showing large amount of positive structures. Conclusions. The amount of PGP 9.5 and CGRP demonstrates relatively good cyst wall innervation. Marked expression of NGFR proves still existing neuronal growth stimulation despite relatively unchanged neuronal cytoskeleton. Negative expression of VEGF proves lack of ischemia. Apoptosis mainly affects inflammatory cells and epiteliocytes, while the choledochal cyst wall presumably is composed of functionaly viable tissue.