bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distribution of Collagen Cross-Links in Normal Human Trabecular Bone
Authors: Paschalis EP , Recker R , Dicarlo E , Doty SB , Atti E , Boskey AL 
Published: April 2006

Abstract
Infrared imaging analysis of normal human iliac crest biopsy specimens shows a characteristic spatial variation in the nonreducible:reducible collagen cross-links at trabecular surfaces, depending on the surfaces' metabolic status.
Introduction: Bone is a composite material consisting of mineral, collagen, non-collagenous proteins, and lipids. Bone collagen, mainly type I, provides the scaffold on which mineral is deposited and imparts specific mechanical properties, determined in part by the amount of collagen present, its orientation and fibril diameter, and the distribution of its cross-links.
Materials and Methods: In this study, the technique of Fourier transform infrared imaging (FTIRI) was used to determine the ratio of nonreducible:reducible cross-links, in 2- to 4-μm-thick sections from human iliac crest biopsy specimens (N = 14) at trabecular surfaces as a function of surface activity (forming versus resorbing), with an ∼6.3-mm spatial resolution. The biopsy specimens were obtained from patients devoid of any metabolic bone disease based on histomorphometric and bone densitometric parameters.
Results and Conclusions: Distributions of collagen cross-links within the first 50 mm at forming trabecular surfaces demonstrated a progressive increase in the nonreducible:reducible collagen cross-link ratio, unlike in the case of resorbing surfaces, in which the collagen cross-links ratio (as defined for the purposes of the present report) was relatively constant.
Patient-Specific DXA Bone Mineral Density Inaccuracies: Quantitative Effects of Nonuniform Extraosseous Fat Distributions
Authors: Bolotin Hh , Sievänen H , Grashuis Jl 
Published: April 2006

Abstract
Nonuniform extraosseous fat is shown to raise the magnitude of inaccuracies in DXA in vivo BMD measurements into the range of 20-50% in clinically relevant cases. Hence, DXA-based bone fragility diagnoses/prognoses and evaluations of bone responsiveness to treatment can be unreliable.
Patient-specific DXA in vivo bone mineral areal density (BMD) measurements have been demonstrated to be inherently inaccurate even when extraosseous fat (F) and lean muscle tissue (L) are uniformly distributed throughout the scan region of interest (ROI). The present work extends these investigations to quantitative evaluation of the extent to which clinically realistic soft tissue inhomogeneities external to the bone within the DXA scan ROI affect patient-specific in vivo BMD measurement inaccuracies. The results are particularly relevant to patient-specific lumbar vertebral and proximal femoral sites. Norland, Hologic, and Lunar DXA scans and corresponding DXA simulation studies of the same set of 225 different phantom arrays were carried out. The phantoms were specially fabricated absorptiometric replications of bone mineral material (B), red marrow (RM), and yellow marrow (YM) mixtures, and extraosseous F and L combinations spanning the anthropometric ranges encountered clinically. The three different DXA scanners yielded BMD results that effectively coincided, were in excellent agreement with the findings of the present corresponding DXA-simulation studies in each case, and confirmed the validity of the DXA BMD inaccuracy analysis formalism. It was found that only relatively small extraosseous soft tissue inhomogeneities within the ROI of DXA BMD scans can increase substantially the already sizable BMD inaccuracies shown earlier to pertain for uniformly distributed extraosseous soft tissues. The extent of these in vivo BMD inaccuracies (%) are shown to depend on the mean extraosseous F-to-L areal density ratio and its degree of nonuniformity within the local bone scan ROI, the marrow thickness and specific composition, and the actual BMD in any given case. It was found that patient-specific DXA-measured in vivo BMD inaccuracies can, in many clinically encountered cases, be as large as 20-50%, particularly so for osteopenic, osteoporotic, and elderly patients. It is concluded that, because these DXA in vivo BMD inaccuracies are unavoidable and clinically unpredictable, diagnoses/prognoses of bone fragility and evaluations of bone responsiveness to treatment of individual patients based mainly on DXA in vivo BMD measurements can be unreliable.
Integrated Single-Label Liquid-Phase Assay of APOE Codons 112 and 158 and a Lipoprotein Study in British Women,
Authors: Abdollahi Mohammad Reza , Guthrie Philip AI , Smith George Davey , Lawlor Debbie A , Ebrahim Shah , Day Ian NM 
Published: April 2006

AbstractBackground: Apolipoprotein E (APOE) is an important element of lipid metabolism and, hence, cardiovascular disorders. APOE has 3 main allelic variants: ε3, ε4, and ε2. Of these, ε3 is the most common, followed by ε4 and ε2. The associations of these isoforms with cardiovascular disorders and Alzheimer disease have been widely studied in different populations. Most of the genotyping in these studies has been performed with gel-based methods, which have important limitations, particularly for large epidemiologic studies. We therefore developed an integrated “one-tube” liquid-phase assay.Methods: To measure APOE isoforms, we developed an integrated single-label liquid-phase fluorescence assay containing 2 PCR primers, 2 probes, and 2 quencher oligonucleotides. We used a 384-well LightTyper, but the assay would be generically applicable for use with any fluorescence detector with thermal ramp control. We validated this method and applied it in the British Women’s Heart and Health Study.Results: There were 4 melting peaks, at 41, 56, 61, and 69 °C, which generated 6 distinctive patterns representing genotypic combinations of ε3, ε4, and ε2. The magnitude and direction of the associations found with total cholesterol, HDL-cholesterol, triglycerides, and estimated LDL-cholesterol were consistent with previous reports.Conclusion: The one-tube LightTyper assay presented here enables accurate, convenient, and economical genotyping of APOE and can be used for large epidemiologic studies.
Frames, schemata, and news reporting
Authors: Scheufele Bertram 
Published: April 2006

Abstract
This article deals with frames and schemata in news reporting. It distinguishes frames and schemata in newsroom discourse and news reports. On the individual cognitive level, a frame is defined as a set of schemata for different aspects of reality. They emerge in newsroom discourse and in exchange with other (media) discourses, i. e., they are not idiosyncratic but shared among those working in a newsroom. It is supposed that news report structures (media frames) correspond to these newsroom frames and schemata. The article discusses these considerations in regard to related explanations of news production, especially attitudinal approaches such as news bias. While the latter assume that journalists prefer information consistent with their own attitudes or that news reporting is ‘synchronized’ with editorial tendencies, the framing approach proposes that information in routine news reports correspond to newsroom frames. In this study I will use xenophobia as an example to identify newsroom frames in a qualitative frame analysis. In the second part of the study, quantitative analysis of news framing examines whether news report information correlates with newsroom frames. Finally, I will present empirical evidence that shows that newsroom frames play a role in news reporting.
Das „Wundergas“ Helium, die US-amerikanische Innenpolitik und die deutschen Zeppeline
Authors: Braun Helmut 
Published: April 2006

Vorspann
Dass es in der Rüstungstechnik ganz bestimmte Schlüsseltechnologien gibt, die über das Technische hinaus eine unabsehbare militärische und politische Wirkung entfalten, ist in der zweiten Hälfte des 20. Jahrhunderts ein bekanntes Phänomen. Dieser Artikel erinnert daran, dass es sich hier nicht um eine Erscheinung aus der Zeit nach 1945 handelt. Am Beispiel eines Naturprodukts, des Edelgases Helium, wird vorgeführt, welche technischen und politischen Folgen die Entdeckung dieses chemischen Elements hatte. Aber nicht nur das. Dieser Artikel vermittelt auch eine Vorstellung davon, wie schnell die Rüstungstechnik in 20 Jahren veralten konnte.
Stalins Aufrüstungsbeschluß. Die Moskauer Beratungen mit den Parteichefs und Verteidigungsministern der „Volksdemokratien“ vom 9. bis 12. Januar 1951
Authors: Wettig Gerhard 
Published: April 2006

Vorspann
Ein weltgeschichtliches Ereignis wie der Kalte Krieg hat viele Väter. Doch ist wie immer auch hier die Verantwortung unterschiedlich verteilt. Stalins Beitrag zur Genese jener langen und tiefgreifenden Konfrontation zwischen Ost und West scheint besonders groß. Das jedenfalls bleibt als Eindruck dieses einzigartigen Schlüsseldokuments. Im Januar 1951 initiierte der sowjetische Diktator in seinem gesamten Machtbereich ein Aufrüstungsprogramm, wie es in der Zeit nach dem Zweiten Weltkrieg bislang ohne Beispiel war und mit dem er zugleich die sowjetische Macht in Ost- und Mitteleuropa noch stärker verankerte.
Mercury exposure and reproduction in fish-eating birds breeding in the Pinchi Lake region, British Columbia, Canada
Authors: Weech Shari A. , Scheuhammer Anton M. , Elliott John E. 
Published: April 2006

AbstractTo determine whether Hg from geologic/mining-related sources at Pinchi Lake (BC, Canada) was causing elevated Hg exposure and/or adversely affecting reproduction in fish-eating birds, breeding bald eagles (Haliaeetus leucocephalus) on Pinchi Lake and four nearby reference lakes were sampled for blood and feather Hg concentrations and monitored for reproductive success during the summers of 2000, 2001, and 2002. Eggs of red-necked grebes (Podiceps grisgena) also were collected and analyzed. Mercury levels in species at various trophic levels from Pinchi Lake averaged approximately twice those in the same species from nearby lakes combined, even in the absence of substantial new inputs of Hg to Pinchi Lake over several decades. In Pinchi Lake, Hg concentrations in blood and feathers of eagles and eggs of grebes were significantly higher than those in corresponding samples from reference lakes. However, the mean Hg concentration (0.25 μg/g wet wt) in grebe eggs from Pinchi Lake was substantially lower than accepted threshold levels for reproductive toxicity in most avian species (0.5–1.0 μg/g wet wt). Mercury concentrations in the blood of adult eagles and their chicks were highly correlated (r = 0.91, p = 0.004). Despite elevated Hg exposure in adult eagles nesting on Pinchi Lake (blood Hg concentration, 4.3–9.4 μg/ml), birds appeared to be in good body condition, did not differ significantly in terms of weight from eagles nesting on reference lakes, and exhibited no evidence of obvious abnormal behavior or lack of coordination. Eagle reproductive success and productivity on Pinchi Lake were not significantly different from those on all reference lakes combined (p = 0.483).
Sublethal effects of lead on northern leopard frog (Rana pipiens) tadpoles
Authors: Chen Te-Hao , Gross Jackson A. , Karasov William H. 
Published: April 2006

AbstractNorthern leopard frogs (Rana pipiens) were exposed to environmentally relevant concentrations of lead in water (3, 10, and 100 μg/L as lead nitrate) from the embryonic stage to metamorphosis. Survival, growth, deformity, swimming ability, metamorphosis, and lead tissue concentrations were evaluated. Tadpole growth was significantly slower in the early stages (Gosner stages 25–30) in 100 μg/L treatment. More than 90% of tadpoles in the 100 μg/L treatment developed lateral spinal curvature, whereas almost all the tadpoles in the other groups were morphologically normal. Spinal deformity was associated with abnormal swimming behavior. Maximum swimming speed of tadpoles in the 100 μg/L treatment was significantly lower than that in the other groups. No significant effect of lead exposure was found on percentage metamorphosis, snout-vent length, mortality, and sex ratio of metamorphs. Time to metamorphosis was delayed in 100 μg/L treatment. Lead tissue concentrations in the tadpoles ranged from 0.1 to 224.5 mg/kg dry mass, were positively related to lead concentrations in the water, and fell within the range of tissue concentrations of wild tadpoles found in previous studies. According to our results, the current U.S. Environmental Protection Agency freshwater-quality chronic criterion for lead (2.5 μg/L) is appropriate to protect northern leopard frog larvae.
Toxicities of dinitrotoluenes and trinitrobenzene freshly amended or weathered and aged in a sandy loam soil toenchytraeus crypticus
Authors: Kuperman Roman G. , Checkai Ronald T. , Simini Michael , Phillips Carlton T. , Kolakowski Jan E. , Kurnas Carl W. 
Published: April 2006

AbstractScientifically based ecological soil-screening levels are needed to identify concentrations of contaminant energetic materials (EMs) in soil that present an acceptable ecological risk at a wide range of military installations. Insufficient information regarding the toxicity of 2,4-dinitrotoluene (2,4-DNT), 2,6-dinitrotoluene (2,6-DNT), and 1,3,5-trinitrobenzene (TNB) to soil invertebrates necessitated toxicity testing. We adapted the standardized Enchytraeid Reproduction Test (International Standardization Organization 16387:2003) and selected Enchytraeus crypticus for these studies. Tests were conducted in Sassafras sandy loam soil, which supports relatively high bioavailability of nitroaromatic EMs. Weathering and aging procedures for EMs amended to test soil were incorporated into the study design to produce toxicity data that better reflect the soil exposure conditions in the field compared with toxicity in freshly amended soils. This included exposing hydrated, EM-amended soils in open glass containers in the greenhouse to alternating wetting and drying cycles. Definitive tests established that the order of EM toxicity to E. crypticus based on the median effect concentration values for juvenile production in either freshly amended or weathered and aged treatments was (from the greatest to least toxicity) TNB &gt; 2,4-DNT &gt; 2,6-DNT. Toxicity to E. crypticus juvenile production was significantly increased in 2,6-DNT weathered and aged soil treatments compared with toxicity in freshly amended soil, based on 95% confidence intervals. This result shows that future investigations should include a weathering and aging component to generate toxicity data that provide more complete information regarding ecotoxicological effects of energetic contaminants in soil.
Selenite transport and its inhibition in the unicellular green alga Chlamydomonas reinhardtii
Authors: Morlon Hélène , Fortin Claude , Adam Christelle , Garnier-Laplace Jacqueline 
Published: April 2006

Abstract
The influence of time, ambient concentration, and medium composition on selenite (Se(IV)) uptake by the unicellular green alga Chlamydomonas reinhardtii has been investigated. The aims of the performed experiments were to describe the kinetics of accumulation, to characterize transport capacities, to identify key nutrients influencing absorption, and to establish links between speciation and bioavailability. Our results suggested that the adsorbed fraction was negligibl compared to the absorbed one. Over the short time scale considered, the absorption was linear with time, with an estimated conductance of approximately 0.2 nmol/m2/h/nM. Uptake was proportional to ambient levels in a broad range of intermediat concentrations (from nM to μM). However, conductances were higher at low concentrations (&lt;nM) and then decreased with increasing concentrations (&gt;μM). These results suggested that a specific but rapidly saturated transport system was involved at low concentrations, coupled with a nonspecific one that was only saturated at high ambient concentrations (∼mM). The latter could involve transporters used by anionic macronutrients, which is supported by the fact that increasing sulfate and nitrate concentrations induced significant inhibition of Se(IV) uptake. Finally, Se(IV) speciation changes caused y varying pH did not significantly affect bioavailability.
Binding diversity of the two binding sites of ricin B lectin
Authors: Ganguly Debabani , Mukhopadhyay Chaitali 
Published: April 2006

AbstractRicin B is a galactose‐binding protein, which contains two binding sites. We have compared the binding properties of the two binding sites of ricin B chain toward different mono‐ and disaccharide ligands. The free energies of binding are calculated using the free energy perturbation simulation (thermodynamic integration method) and linear interaction energy approach using CHARMM force field. The second binding site of the protein was found to be weaker compared to the first. The details of the hydrogen‐bonding scheme suggested the origin of the epimeric specificity of the protein. The reason for the weaker binding capacity of the second binding site has been addressed. © 2006 Wiley Periodicals, Inc. Biopolymers 83: 83–94, 2006This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Frequent gene dosage alterations in stromal cells of epithelial ovarian carcinomas
Authors: Tuhkanen Hanna , Anttila Maarit , Kosma Veli‐Matti , Heinonen Seppo , Juhola Matti , Helisalmi Seppo , Kataja Vesa , Mannermaa Arto 
Published: April 2006

AbstractStromal cells are an active and integral part of epithelial neoplasms. We have previously observed allelic imbalance on chromosome 3p21 in both stromal and epithelial cells of ovarian tumors. This study was designed to explore gene dosage alterations throughout human chromosomes from stromal and epithelial cells of epithelial ovarian carcinomas. Thirteen stromal and 24 epithelial samples, microdissected from epithelial ovarian carcinomas, were analyzed using multiplex ligation‐dependent probe amplification technique. Analysis covered 110 cancer related genes. Frequent genetic alterations were detected both in the stroma and epithelium of ovarian carcinomas. The mean number of altered genes per tumor was 10.8 in stroma and 23.6 in epithelium. In the stroma, the mean number of gains was 6.6 and of losses 4.2 and in the epithelium 13.7 and 9.9. The high number of changes associated with advanced tumor stage (p = 0.035) and death due to ovarian cancer (p = 0.032). The most frequent alteration was the deletion of the deleted in colorectal carcinoma (DCC) on chromosome 18q21.3 in 62% of samples. Loss of DCC was related to endometrioid subtype (p = 0.033). Large chromosomal aberrations were detected on the basis of alterations in adjacent genes. Most importantly, 38 genes showed similar genetic alterations (gain–gain or loss–loss) in stromal and epithelial compartments of 11 tumor pairs. Thus, frequent genetic alterations in stromal cells of epithelial ovarian carcinomas resembled those of malignant epithelial cells and may indicate a common precursor cell type. Epithelial–mesenchymal transition may generate transformed cancer cells and modify the tumor microenvironment with distinct properties. © 2006 Wiley‐Liss, Inc.
Radon, secondhand smoke, glutathione‐S‐transferase M1 and lung cancer among women
Authors: Bonner Matthew R. , Bennett William P. , Xiong Wenying , Lan Qing , Brownson Ross C. , Harris Curtis C. , Field R. William , Lubin Jay H. , Alavanja Michael C.R. 
Published: April 2006

AbstractTobacco smoke and ionizing radiation induce oxidative stress by transmitting or generating reactive oxygen species (ROS). We hypothesized that glutathione‐S‐transferase M1 (GSTM1) null homozygotes would have decreased ability to neutralize ROS that might increase their susceptibility to lung cancer. A case‐only design was used with lung cancer cases pooled from 3 previously completed case‐control studies using archival tissue samples from 270 lung cancer cases to genotype GSTM1. Radon concentrations were measured with long‐term α‐track radon detectors. Secondhand smoke (SHS) was measured with questionnaires and interviews. Unconditional logistic regression was used to calculate the interaction odds ratios (OR) and 95% confidence intervals (95% CI). Radon concentrations >121 Bq m−3 were associated with a >3‐fold interaction OR (OR = 3.41; 95% CI = 1.10, 10.61) for GSTM1 null homozygotes compared to GSTM1 carriers; the linear trend was significant (p trend = 0.03). The SHS and GSTM1 interaction OR was also elevated (OR = 2.28; 95% CI = 1.15–4.51) among never‐smokers. This may be the first study to provide evidence of a GSTM1 and radon interaction in risk of lung cancer. Additionally, these findings support the hypothesis that radon and SHS promote neoplasia through shared elements of a common pathway. © 2006 Wiley‐Liss, Inc.
Die Werkstoffermüdung bei Wälzbeanspruchung – Eine Hypothese zum Mechanismus
Authors: Schlicht H. 
Published: April 2006

AbstractDie Erforschung der Wälzermüdung liefert eine Fülle experimenteller Ergebnisse und theoretischer Erkenntnisse. Aus einer Zusammenschau dieser bekannten Einzel‐Informationen wird eine Hypothese zum Mechanismus der Wälzermüdung entwickelt und im Folgenden vorgestellt. Nach dieser Hypothese läuft der Ermüdungsprozess in drei Phasen ab. In den Phasen 1 und 2 wird der Werkstoff mikroplastisch verformt. Das Gefüge verliert an Festigkeit. Es entstehen Druckeigenspannungen, die sich den Lastspannungen überlagern und die Belastung stetig verändern. Die Verformungen kommen in der Phase 2 annähernd zum Stillstand. Bei einem kritischen Werkstoff‐ und Eigenspannungszustand, dem Übergang der Phase 2 in die Phase 3, geht die mikroplastische Verformung in einen makroplastischen Vorgang über. Das Gefüge „fließt”︁ in Teilbereichen – entsprechend der dann vorliegenden Richtung der „relativen”︁ Zugspannungen – zunehmend in Richtung Oberfläche. Dort entstehen zu beiden Seiten der Laufbahnfläche Aufwölbungen. Auch in der Laufbahn selbst entstehen Aufwölbungen; sie werden aber durch die Überrollungen wieder eingeebnet. Hierdurch bilden sich Zugeigenspannungen senkrecht zur Oberfläche. Die Eigenspannungen nehmen zu und lösen schließlich während der Entlastung, die der Überrollung folgt, die Bildung von „subsurface cracks”︁ aus.Die Hypothese vermittelt ein Ermüdungsmodell, das die Phänomene, die bislang bei der experimentellen Erforschung des Ermüdungsvorgangs festgestellt wurden, weitgehend erklärt.Sie eröffnet Möglichkeiten, Wälzsysteme auch weiterhin in ihrer Leistungsfähigkeit zu optimieren.
The secondary flow and its stability for natural convection in a tall vertical enclosure
Authors: Chait Arnon , Korpela Seppo A. 
Published: April 2006

The multicellular flow between two vertical parallel plates is numerically simulated using a time-splitting pseudospectral method. The steady flow of air, and the time-periodic flow of oil (Prandtl numbers of 0.71 and 1000, respectively) are investigated and descriptions of these flows using both physical and spectral approaches are presented. The details of the time dependency of the flow and temperature fields of oil are shown, and the dynamics of the process is discussed. The spectral transfer of energy among the axial modes comprising the flow is explored. The spectra of kinetic energy and thermal variance for air are found to be smooth and viscously dominated. Similar spectra for oil are bumpier, and the dynamics of the time-dependent flow are determined to be confined to the lower end of the spectrum alone.The three-dimensional linear stability of the multicellular flow of air is parametrically studied. The domain of stable two-dimensional cellular motion was found to be constrained by the Eckhaus instability and by two types of monotone instability. The two-dimensional multicellular flow is unstable above a Grashof number of about 8550 (with the critical Grashof number for the base flow being 8037). Therefore the flow of air in a sufficiently tall vertical enclosure should be considered to be three-dimensional for most practical applications.