bluuebunny/crossref_metadata_2025 huggingface dataset:
An Investigation into Fracture of Multi-Crystalline Silicon
Authors: Mansfield B.R. , Armstrong David E.J. , Wilshaw Peter R. , Murphy John D.
Published: October 2009

As the thickness of multi-crystalline silicon solar cells continues to reduce, understanding the mechanical properties of the material is of increasing importance. In this study, a variety of techniques are used to study multi-crystalline silicon. Fracture tests are performed using four- and three-point bending. The fracture stress of as-sawn material reduces with increasing beam width and is increased in beams with a polished front surface. This indicates that fracture initiates from surface flaws. Modifications to standard fracture testing, including testing under liquid, are made so that beams fracture into just two pieces. By determining the crystallography either side of the location of fracture, multi-crystalline silicon was found to fail by transgranular fracture in the samples studied. Further evidence for this is gained from indentation experiments at grain boundaries. In order to understand the relative strength of grain boundaries, new approaches need to be considered. Therefore, a novel micromechanical technique, which enables individual grain boundaries to be studied, has started to be applied to multi-crystalline silicon. A focused ion beam is used to mill micron-scale cantilevers across notched grain boundaries, which are then loaded to fracture using the tip of a nanoindenter. The technique is shown to reproduce the known fracture toughness of {110} planes in single-crystal silicon, giving a value of 0.7 ± 0.3MPam1/2. Preliminary results are presented for fracture of multi-crystalline silicon.
Structural and Luminescent Properties of Implanted Silicon Layers with Dislocation-Related Luminescence
Authors: Sobolev N.A. , Kalyadin  , Kyutt R.N. , Shek Elena I. , Vdovin V.I.
Published: October 2009

Structural and luminescence properties have been studied in silicon layers with dislocation-related luminescence. Multiple room temperature implantation of oxygen ions with doses low than the amorphization threshold was carried out. Silicon ions with a dose exceeding the amorphization threshold by two orders of magnitude were implanted at a higher temperature
(≥ 80°C). Both the implantations were not followed by the amorphization of the implanted layers. Annealing in a chlorine-containing atmosphere resulted in formation of extended structural defects and luminescence centers. Some regularities and peculiarities in the properties of the extended defects and dislocation-related luminescence lines were revealed in dependence on the implantation and annealing conditions.
Advanced Si-based Semiconductors for Energy and Photonic Applications
Authors: Kouvetakis J. , Menendez Jose , Tolle John
Published: October 2009

Group-IV semiconductors, including alloys incorporating Sn, have been grown on dimensionally dissimilar Si substrates using novel molecular hydride chemistries with tunable reactivities that enable low temperature, CMOS compatible integration via engineering of the interface microstructure. Here we focus on properties of three such Ge-based systems including: (1) device quality Ge layers with thicknesses >5m possessing dislocation densities <105/cm2 are formed using molecular mixtures of Ge2H6 and highly reactive (GeH3)2CH2 organometallic additives circumventing the classical Stranski-Krastanov growth mechanism, (2) metastable GeSn alloys are grown on Si via reactions of Ge2H6 and SnD4, and (3) ternary SiGeSn analogs are produced lattice-matched to Ge-buffered Si using admixtures of SiGeH6, SiGe2H8, SnD4, Ge2H6, and Si3H8. Optical experiments and prototype device fabrication demonstrate that the ternary SiGeSn system represents the first group-IV alloy with a tunable electronic structure at fixed lattice constant, effectively decoupling band gap and strain and eliminating the most important limitation in device designs based on group-IV materials. Doping at levels higher than 1019 cm-3 (both p and n-type) is achieved for all the above semiconductor systems using a similar precursor chemistry approach. Electrical and infrared optical experiments demonstrate that doped GeSn and SiGeSn have mobilities that compare or exceed that of bulk Ge. The potential applications of these materials, including micro- and optoelectronics as well as photovoltaics and thermoelectricity, are discussed.
Development of sustainable resource‐based nanostructured polyaniline/castor oil polyurethane composites
Authors: Ahmad Sharif , Riaz Ufana , Alam Javed
Published: October 2009

Processibility is one of the important requirements for the commercial utilization of conducting polymers. Studies on composites and blends based on nano polyaniline (PANI) dispersions have become the subject of scientific curiosity with regard to their morphology, stability, and electron transport properties. In general, polymer nanocomposites are made by dispersing inorganic or organic nanoparticles into either a conventional thermoplastic or thermoset polymer. The present study reports the synthesis of nanostructured MO‐PANI and castor oil polyurethane (COPU)–based composites. The effect of loading of nanostructured MO‐PANI in COPU on the spectral, physicochemical and morphological properties has been analyzed. © 2009 Wiley Periodicals, Inc. Adv Polym Techn 28:26–31, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20143
In situ generated hydroxyl‐terminated polybutadiene nanoparticles in polyimide films
Authors: Gupta Anand Kumar , Kurmvanshi S. K. , Bajpai R. , Keller J. M.
Published: October 2009

Polyimide (PI) has been extensively investigated as matrices for blends in the search for novel materials for microelectronics and engineering application. The processing of the PI with hydroxyl‐terminated polybutadiene (HTPB) offers a considerable advantage to develop a material having good mechanical and thermal stability. Taking this into account, the HTPB was blended with polyamic acid, which is precursor to PI to form PI + HTPB films. A number of properties were evaluated for PI + HTPB films with ultra low concentrations of HTPB. The films prepared with ultra low concentration (10−3–1 wt%) showed unusual synergism, which is attributed to the presence of in situ generated micro/nanostructures derived from HTPB. The microhardness study was used to elucidate the actual mechanical performance due to structure formation of HTPB in a nanometer regime within PI matrix. Atomic force microscopy analysis confirmed the dispersion of HTPB at nano regime within PI matrix. The enhanced thermal stability as determined by thermogravimetric analyzer and Fourier transform infrared spectrometry was attributed to the presence of micro/nanoparticle of HTPB within the PI matrix. The water absorption isotherms were measured and their abnormal behavior was correlated with micro‐/nano‐sized particles in the PI/HTPB film. © 2009 Wiley Periodicals, Inc. Adv Polym Techn 28:48–59, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20144
Synthesis and characterization of uniform‐sized hollow chitosan microspheres
Authors: Wang Shan , Yu Demei
Published: October 2009

Hollow chitosan (CS) microspheres were obtained using an inverse‐emulsion crosslinking method. The temperature and viscosity of the CS emulsion affected the characteristics of the derived microspheres. The microspheres were characterized by differential scanning calorimetry, Fourier transform infrared (FT‐IR) spectroscopy, transmission electron microscopy, optical microscopy, scanning electron microscopy (SEM), and laser particle size analysis. FT‐IR indicated the sequence of transformations taking place before, during, and after the crosslinking of CS. Optical microscopy and SEM confirmed the spherical morphology of the gel. The formation of hollow microspheres with a single cavity was identified by SEM. The CS microspheres exhibited a narrow particle size distribution. Furthermore, particle size could be controlled by changing the stirring speed. © 2009 Wiley Periodicals, Inc. Adv Polym Techn 28:40–47, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20145
An investigation into the swelling properties, dimensional changes, and gel layer evolution in chitosan tablets undergoing hydration
Authors: Efentakis Manuel , Stamoylis Konstantinos
Published: October 2009

The purpose of this research is to determine several characteristics of chitosan lactate in tablet form such as dimensional changes, gel evolution, swelling (liquid uptake), and erosion using an image analysis method. The examination of these characteristics will be helpful in the design of oral drug delivery systems with this polymer. It has been demonstrated that image analysis is a valuable technique, allowing the study of quantitative measurements of dimensional and core changes and gel evolution. The dimensional expansion changes of the chitosan lactate tablets were greater in water, and the crushing strength and the stirring effect affected these attributes to a limited extent. The fastest and greatest liquid uptake was observed in water, whereas the greatest erosion was observed in HCl. The thickness of the gel layer increased considerably with time up to the eighth hour, indicating the formation and development of a thick and durable gel, particularly in water. This is an essential characteristic for potential sustained drug release delivery. Consequently, this polymer appears to be a versatile material and a promising vehicle for the preparation of various oral sustained release medications and relevant devices. © 2009 Wiley Periodicals, Inc. Adv Polym Techn 28:32–39, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20147
Modeling of turbulent precipitation: A transported population balance‐PDF method
Authors: di Veroli Giovanni , Rigopoulos Stelios
Published: October 2009

Turbulent precipitation is a complex problem, whose mathematical description of precipitation requires a coupling of fluid dynamics with the population balance equation (PBE). In the case of turbulent flow, this coupling results in unclosed equations due to the nonlinear nature of precipitation kinetics. In this article, we present a methodology for modeling turbulent precipitation using the concept of the transported probability density function (PDF) in conjunction with a discretized PBE, simulated via a Lagrangian stochastic method. The transported PBE‐PDF approach resolves the closure problem of turbulent precipitation for arbitrarily complex precipitation kinetics, while retrieving the full particle size distribution (PSD). The method is applied to the precipitation of BaSO4 in a turbulent pipe flow and comparisons are made with the experimental results of Baldyga and Orciuch (Chem Eng Sci. 2001;56:2435‐2444) showing excellent agreement, while insight is drawn into the mechanisms that determine the evolution of the product PSD. © 2009 American Institute of Chemical Engineers AIChE J, 2010
Paternal balanced reciprocal translocation t(9;22)(q34.3;q11.2) resulting in an lnfant with features of the 9q subtelomere and the 22q11 deletion syndromes due to 3:1 meiotic segregation and tertiary monosomy
Authors: McGoey Robin R. , Lacassie Yves
Published: October 2009

The constitutional chromosomal reciprocal translocation (CRT) involving chromosomes 9 and 22 has been previously published in only five occasions. We report the sixth case of a balanced t(9;22) carrier who came to medical attention following the birth of his child with tertiary monosomy due to 3:1 meiotic segregation. This is only the second occurrence of paternal parent‐of‐origin to the t(9;22) CRT and is the first report of a t(9;22) undergoing 3:1 disjunction. It is also unique in its constellation of clinical features that overlap with two well‐described cytogenetic microdeletion syndromes: the 9q subtelomeric and 22q11.2 deletion syndromes. With its uncommon breakpoint at chromosome 9q34, this case also emphasizes the added importance of array comparative genomic hybridization to analysis of offspring born to CRT carrier parents. © 2009 Wiley‐Liss, Inc.
Population‐based Tay‐Sachs screening among Ashkenazi Jewish young adults in the 21st century: Hexosaminidase a enzyme assay is essential for accurate testing
Authors: Schneider Adele , Nakagawa Sachiko , Keep Rosanne , Dorsainville Darnelle , Charrow Joel , Aleck Kirk , Hoffman Jodi , Minkoff Sherman , Finegold David , Sun Wei , Spencer Andrew , Lebow Johannah , Zhan Jie , Apfelroth Stephen , Schreiber‐Agus Nicole , Gross Susan
Published: October 2009

Tay‐Sachs disease (TSD) carrier screening, initiated in the 1970s, has reduced the birth‐rate of Ashkenazi Jews with TSD worldwide by 90%. Recently, several nationwide programs have been established that provide carrier screening for the updated panel of Jewish genetic diseases on college campuses and in Jewish community settings. The goals of this study were to determine the performance characteristics of clinical TSD testing in college‐ and community‐based screening programs and to determine if molecular testing alone is adequate in those settings. Clinical data for TSD testing were retrospectively anonymized and subsequently analyzed for 1,036 individuals who participated in these programs. The performance characteristics of the serum and the platelet Hexosaminidase assays were compared, and also correlated with the results of targeted DNA analysis. The serum assay identified 29 carriers and the platelet assay identified 35 carriers for carrier rates of 1/36 and 1/29, respectively. One hundred sixty‐nine samples (16.3%) were inconclusive by serum assay in marked contrast to four inconclusive samples (0.4%) by the platelet assay. Molecular analysis alone would have missed four of the 35 carriers detected by the platelet assay, yielding a false negative rate of 11.4% with a sensitivity of 88.6%. Based on the results of this study, platelet assay was superior to serum with a minimal inconclusive rate. Due to changing demographics of the Ashkenazi Jewish population, molecular testing alone in the setting of broad‐based population screening programs is not sufficient, and biochemical analysis should be the assay of choice. © 2009 Wiley‐Liss, Inc.
The genetics of sleep disorders in humans: Narcolepsy, restless legs syndrome, and obstructive sleep apnea syndrome
Authors: Caylak Emrah
Published: October 2009

Sleep disorders are a group of neurological disorders known to cause public health problems associated with interference with daily activities including cognitive problems, poor job performance and reduced productivity. There is strong evidence emerging for the presence of genes influencing sleep disorders, such as narcolepsy (NRCLP), restless legs syndrome (RLS), and obstructive sleep apnea syndrome (OSAS). NRCLP is typically characterized by excessive daytime sleepiness, cataplexy, sleep paralysis and hallucinations. RLS is manifested by compelling need to move the legs and usually experienced when trying to sleep. OSAS is major sleep problem characterized by recurrent episodes of upper airway collapse and obstruction during sleep. In the recent years, many research groups have attempted to identify the susceptibility and candidate genes for NRCLP, RLS, and OSAS through the sequential analyses of genetic linkage and association. The purpose of this review is to summarize some of remarkable molecular advances in sleep and sleep disorders, thereby providing a greater understanding of the complex sleep processes, and a platform for future therapeutic interventions. © 2009 Wiley‐Liss, Inc.
Diaryliodoniumsalze – aus dem Nichts ins Rampenlicht
Authors: Merritt Eleanor A. , Olofsson Berit
Published: October 2009

Die jüngsten bahnbrechenden Entwicklungen bei der Anwendung von Diaryliodoniumsalzen in Kreuzkupplungsreaktionen haben diese ehemals unterentwickelte Klasse von Reagentien in die vorderste Reihe der organischen Chemie katapultiert. Mit dem Aufkommen neuartiger, einfacher, effizienter Methoden zur Synthese dieser Reagentien lassen sich noch sehr viel mehr Einsatzmöglichkeiten voraussehen. Wir bieten hier einen Überblick über die historischen und neuerlichen Fortschritte bei der Synthese und Anwendung von Diaryliodoniumsalzen.
New and Old Concepts in Thermoelectric Materials
Authors: Sootsman Joseph R. , Chung Duck Young , Kanatzidis Mercouri G.
Published: October 2009

Herein we cover the key concepts in the field of thermoelectric materials research, present the current understanding, and show the latest developments. Current research is aimed at increasing the thermoelectric figure of merit (ZT) by maximizing the power factor and/or minimizing the thermal conductivity. Attempts at maximizing the power factor include the development of new materials, optimization of existing materials by doping, and the exploration of nanoscale materials. The minimization of the thermal conductivity can come through solid‐solution alloying, use of materials with intrinsically low thermal conductivity, and nanostructuring. Herein we describe the most promising bulk materials with emphasis on results from the last decade. Single‐phase bulk materials are discussed in terms of chemistry, crystal structure, physical properties, and optimization of thermoelectric performance. The new opportunities for enhanced performance bulk nanostructured composite materials are examined and a look into the not so distant future is attempted.
Magnetic survey in the investigation of sociopolitical change at a Late Bronze age fortress settlement in northwestern Armenia
Authors: Lindsay Ian , Smith Adam T. , Badalyan Ruben
Published: October 2009

The construction of large stone fortresses across much of northern Armenia during the Late Bronze Age (ca. 1500–1150 BC) represented a shift away from centuries of nomadic pastoralism, and also marked a profound transformation in the constitution of political authority and how social orders were mediated through the built environment. To date, however, little archaeological attention has been given to Late Bronze Age (LBA) settlements located outside the fortress citadels, partly due to the difficulty in detecting them from the surface. In this report we highlight results and observations from a magnetic gradiometry survey in northwestern Armenia where we test the hypothesis that an extensive LBA domestic complex existed at the base of the fortified hill at the site of Tsaghkahovit. The study surveyed four grids in the settlement area at the base of fortress. Three test units were excavated in three of the four survey areas to test selected anomalies. Two of the test units confirmed the presence of subsurface LBA deposits, including basalt stone walls, burned features, and a storage pit, appearing in the data as large dipoles. The spatial configurations of buildings revealed by the gradiometry surveys elucidate the extent of the Tsaghkahovit settlement and the formal differentiation of domestic and institutional spaces as new architectural traditions emerge during the Middle to Late Bronze Age transition. However, targeted subsurface tests also hint at the ephemeral nature of the domestic constructions suggesting the retention of mobility among subject populations under the authority of settled fortress elites. Copyright © 2009 John Wiley & Sons, Ltd.
Functional and work outcomes improve in patients with rheumatoid arthritis who receive targeted, comprehensive occupational therapy
Authors: Macedo Alyssa M. , Oakley Stephen P. , Panayi Gabriel S. , Kirkham Bruce W.
Published: October 2009

Objective

Work disability is a serious consequence of rheumatoid arthritis (RA). We conducted a 6‐month, prospective randomized controlled trial comparing assessments of function, work, coping, and disease activity in employed patients with RA receiving occupational therapy intervention versus usual care.

Methods

Employed patients with RA with increased perceived work disability risk were identified by the RA Work Instability Scale (WIS; score ≥10). Patients were stratified into medium‐ (score ≥10 and <17) and high‐risk (≥17) groups, then randomized into occupational therapy or usual care groups. Assessments were conducted at baseline and 6 months. The primary outcome was the Canadian Occupational Performance Measure (COPM), a standardized patient self‐report of function. Other outcomes included the disability index (DI) of the Health Assessment Questionnaire (HAQ); Disease Activity Score in 28 joints (DAS28); RA WIS; EuroQol Index; visual analog scales (VAS) for pain, work satisfaction, and work performance; and days missed/month. Independent sample t‐tests and Mann‐Whitney U tests were used.

Results

We recruited 32 employed patients with RA. At baseline the groups were well matched. At 6 months the improvement in the occupational therapy group was significantly greater than that in the usual care group for all functional outcomes (COPM performance P < 0.001, COPM satisfaction P < 0.001, HAQ DI P = 0.02) and most work outcomes (RA WIS [P = 0.04], VAS work satisfaction [P < 0.001], VAS work performance [P = 0.01]). Additionally, Arthritis Helplessness Index (P = 0.02), Arthritis Impact Measurement Scales II pain subscale (P = 0.03), VAS pain (P = 0.007), EuroQol Index (P = 0.02), EuroQol global (P = 0.02), and DAS28 (P = 0.03) scores significantly improved.

Conclusion

Targeted, comprehensive occupational therapy intervention improves functional and work‐related outcomes in employed RA patients at risk of work disability.
The infrapatellar fat pad in knee osteoarthritis: An important source of interleukin‐6 and its soluble receptor
Authors: Distel Emilie , Cadoudal Thomas , Durant Sylvie , Poignard Alexandre , Chevalier Xavier , Benelli Chantal
Published: October 2009

Objective

Obesity is a potent risk factor in knee osteoarthritis (OA). It has been suggested that adipokines, secreted by adipose tissue (AT) and largely found in the synovial fluid of OA patients, derive in part from the infrapatellar fat pad (IFP), also known as Hoffa's fat pad. The goal of this study was to characterize IFP tissue in obese OA patients and to compare its features with thigh subcutaneous AT to determine whether the IFP contributes to local inflammation in knee OA via production of specific cytokines.

Methods

IFP and subcutaneous AT samples were obtained from 11 obese women (body mass index ≥30 kg/m2) with knee femorotibial OA. Gene expression was measured by real‐time quantitative polymerase chain reaction. Cytokine concentrations in plasma and in conditioned media of cultured AT explants were determined by enzyme‐linked immunosorbent assay or by Luminex xMAP technology.

Results

In IFP tissue versus subcutaneous AT, there was a decrease in the expression of genes for key enzymes implicated in adipocyte lipid metabolism, whereas the expression levels of genes for AT markers remained similar. A 2‐fold increase in the expression of the gene for interleukin‐6 (IL‐6), a 2‐fold increase in the release of IL‐6, and a 3.6‐fold increase in the release of soluble IL‐6 receptor (sIL‐6R) were observed in IFP samples, compared with subcutaneous AT, but the rates of secretion of other cytokines in IFP samples were similar to the rates in subcutaneous AT. In addition, leptin secretion was decreased by 40%, whereas adiponectin secretion was increased by 70%, in IFP samples versus subcutaneous AT.

Conclusion

Our results indicate that the IFP cytokine profile typically found in OA patients could play a role in paracrine inflammation via the local production of IL‐6/sIL‐6R and that such a profile might contribute to damage in adjacent cartilage.
BANK1 is a genetic risk factor for diffuse cutaneous systemic sclerosis and has additive effects with IRF5 and STAT4
Authors: Dieudé P. , Wipff J. , Guedj M. , Ruiz B. , Melchers I. , Hachulla E. , Riemekasten G. , Diot E. , Hunzelmann N. , Sibilia J. , Tiev K. , Mouthon L. , Cracowski J. L. , Carpentier P. H. , Distler J. , Amoura Z. , Tarner I. , Avouac J. , Meyer O. , Kahan A. , Boileau C. , Allanore Y.
Published: October 2009

Objective

To determine whether the functional BANK1 variants rs3733197 and rs10516487 are associated with systemic sclerosis (SSc) in 2 European Caucasian populations and to investigate the putative gene–gene interactions between BANK1 and IRF5 as well as STAT4.

Methods

BANK1 single‐nucleotide polymorphisms were genotyped in a total population of 2,432 individuals. The French cohort consisted of 874 SSc patients and 955 controls (previously genotyped for both IRF5 rs2004640 and STAT4 rs7574865). The German cohort consisted of 421 SSc patients and 182 controls.

Results

The BANK1 variants were found to be associated with diffuse cutaneous SSc (dcSSc) in both cohorts, providing an odds ratio (OR) of 0.77 for the rs10516487 T rare allele in the combined populations of dcSSc patients as compared with the combined populations of controls (95% confidence interval [95% CI] 0.64–0.93) and an OR of 0.73 (95% CI 0.61–0.87) for the rs3733197 A rare allele. BANK1 haplotype analysis found the A‐T haplotype to be protective in dcSSc patients (OR 0.70 [95% CI 0.57–0.86], P = 3.39 × 10−4) and the G‐C haplotype to be a risk factor (OR 1.25 [95% CI 1.06–1.47], P = 0.008). Significant differences were also observed when the limited cutaneous subset of SSc was compared with the dcSSc subset, both for the rare alleles and for the haplotypes. The BANK1, IRF5, and STAT4 risk alleles displayed a multiplicatively increased risk of dcSSc of 1.43‐fold.

Conclusion

Our results establish BANK1 as a new SSc genetic susceptibility factor and show that BANK1, IRF5, and STAT4 act with additive effects.
Altered skeletal expression of sclerostin and its link to radiographic progression in ankylosing spondylitis
Authors: Appel Heiner , Ruiz‐Heiland Gisela , Listing Joachim , Zwerina Jochen , Herrmann Martin , Mueller Ruediger , Haibel Hildrun , Baraliakos Xenofon , Hempfing Axel , Rudwaleit Martin , Sieper Joachim , Schett Georg
Published: October 2009

Objective

Osteocytes are considered to be sensors of bone damage and regulators of bone mass by specifically expressing sclerostin, an inhibitor of bone formation. The contribution of osteocytes in regulating local bone remodeling in arthritis is unknown. The aim of this study was to investigate the role of osteocytes as contributors to bone remodeling in ankylosing spondylitis (AS).

Methods

Sclerostin expression and osteocyte death were assessed by immunohistochemistry in joints derived from patients with AS, patients with rheumatoid arthritis (RA), and patients with osteoarthritis (OA), as well as from control subjects. In addition, the serum level of sclerostin was assessed by enzyme‐linked immunosorbent assay in healthy subjects and patients with AS; this assessment included the longitudinal correlation of sclerostin serum levels and radiographic progression in the spine of patients with AS.

Results

Sclerostin expression was confined exclusively to osteocytes. Whereas the majority of osteocytes in healthy individuals and patients with RA were sclerostin positive, expression was significantly reduced in patients with OA and was virtually absent in patients with AS. Moreover, serum levels of sclerostin were significantly lower in patients with AS than in healthy individuals. Importantly, low serum sclerostin levels in patients with AS were significantly associated with the formation of new syndesmophytes (P = 0.007).

Conclusion

Sclerostin expression is impaired in patients with AS, suggesting a specific alteration of osteocyte function in this disease. A low serum level of sclerostin in the setting of AS is linked to increased structural damage, emphasizing the role of sclerostin in the suppression of bone formation.
The relationship between synovial lymphocyte aggregates and the clinical response to infliximab in rheumatoid arthritis: A prospective study
Authors: Klaasen Ruth , Thurlings Rogier M. , Wijbrandts Carla A. , van Kuijk Arno W. , Baeten Dominique , Gerlag Danielle M. , Tak Paul P.
Published: October 2009

Objective

Some patients with rheumatoid arthritis (RA) exhibit lymphocyte aggregates in the synovium. This study was undertaken to address whether the presence of lymphocyte aggregates before treatment could serve as a biomarker for the clinical response to tumor necrosis factor (TNF) blockade, and to confirm whether the aggregation of synovial lymphocytes is reversible after anti‐TNF treatment.

Methods

Synovial tissue biopsy samples were obtained from 97 patients with active RA before the initiation of infliximab treatment. Lymphocyte aggregates in the synovial tissue were counted and also graded for size. Logistic regression analysis was performed to identify whether the presence of lymphocyte aggregates could be a predictor of the clinical response at week 16. Furthermore, the effects of TNF blockade on lymphocyte aggregates were compared between patients with RA and patients with psoriatic arthritis (PsA).

Results

Fifty‐seven percent of RA synovial tissue samples contained lymphocyte aggregates, and 32% of the patients had large aggregates. Aggregates were found in 67% of clinical responders compared with 38% of nonresponders. The presence of aggregates at baseline was a highly significant predictor of the clinical response to anti‐TNF treatment (R2 = 0.10, P = 0.008). Positivity for lymphocyte aggregates increased the power to predict the clinical response (R2 = 0.29), when analyzed in a prediction model that included baseline disease activity evaluated by the Disease Activity Score in 28 joints, anti–cyclic citrullinated peptide antibody positivity, and synovial TNFα expression. There was a reduction in lymphocyte aggregates after anti‐TNF antibody therapy in both RA and PsA.

Conclusion

RA patients with synovial lymphocyte aggregates have, on average, a better response to infliximab treatment than those with only diffuse leukocyte infiltration. Moreover, the aggregation of synovial lymphocytes is reversible after anti‐TNF antibody treatment.
Tumor necrosis factor α and interleukin‐1β modulate calcium and nitric oxide signaling in mechanically stimulated osteocytes
Authors: Bakker A. D. , da Silva V. C. , Krishnan R. , Bacabac R. G. , Blaauboer M. E. , Lin Y.‐C. , Marcantonio R. A. C. , Cirelli J. A. , Klein‐Nulend J.
Published: October 2009

Objective

Inflammatory diseases often coincide with reduced bone mass. Mechanoresponsive osteocytes regulate bone mass by maintaining the balance between bone formation and resorption. Despite its biologic significance, the effect of inflammation on osteocyte mechanoresponsiveness is not understood. To fill this gap, we investigated whether the inflammatory cytokines tumor necrosis factor α (TNFα) and interleukin‐1β (IL‐1β) modulate the osteocyte response to mechanical loading.

Methods

MLO‐Y4 osteocytes were incubated with TNFα (0.5–30 ng/ml) or IL‐1β (0.1–10 ng/ml) for 30 minutes or 24 hours, or with calcium inhibitors for 30 minutes. Cells were subjected to mechanical loading by pulsatile fluid flow (mean ± amplitude 0.7 ± 0.3 Pa, 5 Hz), and the response was quantified by measuring nitric oxide (NO) production using Griess reagent and by measuring intracellular calcium concentration ([Ca2+]i) using Fluo‐4/AM. Focal adhesions and filamentous actin (F‐actin) were visualized by immunostaining, and apoptosis was quantified by measuring caspase 3/7 activity. Cell‐generated tractions were quantified using traction force microscopy, and cytoskeletal stiffness was quantified using optical magnetic twisting cytometry.

Results

Pulsatile fluid flow increased [Ca2+]iwithin seconds (in 13% of cells) and NO production within 5 minutes (4.7‐fold). TNFα and IL‐1β inhibited these responses. Calcium inhibitors decreased pulsatile fluid flow–induced NO production. TNFα and IL‐1β affected cytoskeletal stiffness, likely because 24 hours of incubation with TNFα and IL‐1β decreased the amount of F‐actin. Incubation with IL‐1β for 24 hours stimulated osteocyte apoptosis.

Conclusion

Our results suggest that TNFα and IL‐1β inhibit mechanical loading–induced NO production by osteocytes via abrogation of pulsatile fluid flow–stimulated [Ca2+]i, and that IL‐1β stimulates osteocyte apoptosis. Since both NO and osteocyte apoptosis affect osteoclasts, these findings provide a mechanism by which inflammatory cytokines might contribute to bone loss and consequently affect bone mass in rheumatoid arthritis.
Brain involvement in rheumatoid arthritis: A magnetic resonance spectroscopy study
Authors: Emmer Bart J. , van der Bijl A. Egon , Huizinga Tom W. J. , Breedveld Ferdinand C. , Steens Stefan C. A. , Th. Bosma Gerlof P. , van Buchem Mark A. , van der Grond Jeroen
Published: October 2009

Objective

Tumor necrosis factor α was recently implicated as an important mediator of communication between the peripheral and cerebral immune systems in an animal model of chronic inflammation. The purpose of this study was to examine by proton magnetic resonance spectroscopy (1H‐MRS) the influence of inflammation on cerebral metabolism in patients with rheumatoid arthritis (RA).

Methods

Single‐voxel 1H‐MRS of the centrum semiovale was performed on 35 RA patients (6 men and 29 women; mean ± SD age 51.8 ± 14.6 years) and 28 healthy age‐ and sex‐matched control subjects (9 men and 19 women; mean ± SD age 50.2 ± 10.4 years). None of the study subjects had any neurologic signs or symptoms. Clinical markers of disease activity were correlated with the 1H‐MRS findings.

Results

Patients with active RA, as reflected by an elevated erythrocyte sedimentation rate (ESR), had a significantly higher ratio of choline to creatine and a significantly lower ratio of N‐acetylaspartate to choline than did patients with inactive RA, as reflected by a normal ESR. Moreover, the ratios of choline to creatine and NAA to choline were significantly correlated with the ESR after correction for age, sex, smoking status, handedness, alcohol consumption, medication use, and disease duration. Medication use had no additional effect on these associations.

Conclusion

Our data show that systemic inflammation in RA is associated with metabolic changes in the brain.
Cancer risk in patients with rheumatoid arthritis treated with anti–tumor necrosis factor α therapies: Does the risk change with the time since start of treatment?
Authors: Askling Johan , van Vollenhoven Ronald F. , Granath Fredrik , Raaschou Pauline , Fored C. Michael , Baecklund Eva , Dackhammar Christina , Feltelius Nils , Cöster Lars , Geborek Pierre , Jacobsson Lennart T. , Lindblad Staffan , Rantapää‐Dahlqvist Solbritt , Saxne Tore , Klareskog Lars
Published: October 2009

Objective

To determine the short‐term and medium‐term risks of cancer in patients receiving anti–tumor necrosis factor α (anti‐TNFα) therapies that have proven effective in the treatment of chronic inflammatory conditions.

Methods

By linking together data from the Swedish Biologics Register, Swedish registers of RA, and the Swedish Cancer Register, we identified and analyzed for cancer occurrence a national cohort of 6,366 patients with RA who first started anti‐TNF therapy between January 1999 and July 2006. As comparators, we used a national biologics‐naive RA cohort (n = 61,160), a cohort of RA patients newly starting methotrexate (n = 5,989), a cohort of RA patients newly starting disease‐modifying antirheumatic drug combination therapy (n = 1,838), and the general population of Sweden. Relative risks (RRs) were estimated using Cox regression analyses, examining overall RR as well as RR by time since the first start of anti‐TNF therapy, by the duration of active anti‐TNF therapy, and by the anti‐TNF agent received.

Results

During 25,693 person‐years of followup in 6,366 patients newly starting anti‐TNF, 240 first cancers occurred, yielding an RR of 1.00 (95% confidence interval 0.86–1.15) versus the biologics‐naive RA cohort, and similar RRs versus the other 2 RA comparators. RRs did not increase with increasing time since the start of anti‐TNF therapy, nor with the cumulative duration of active anti‐TNF therapy. During the first year following the first treatment start, but not thereafter, dissimilar cancer risks for adalimumab, etanercept, and infliximab were observed.

Conclusion

During the first 6 years after the start of anti‐TNF therapy in routine care, no overall elevation of cancer risk and no increase with followup time were observed.
Recursive identification for dynamic systems with backlash
Authors: Dong Ruili , Tan Yonghong , Chen Hui
Published: October 2009

A recursive algorithm for identification of nonlinear dynamic systems with backlash is proposed in this paper. In this method, the backlash, which is a non‐smooth function, is decomposed into a combination of a group of piecewise linearized models so that all the parameters of the backlash can be estimated separately. Moreover, the model of the backlash is embedded into a Hammerstein‐type model. Thus, a pseudo‐Hammerstein model with backlash is constructed. The estimation of the parameters for such a non‐smooth nonlinear system can be implemented through a so‐called recursive general identification algorithm (RGIA). Then, the corresponding convergence analysis of the RGIA for the model with backlash is also investigated. After that, two examples are presented to show the performance of the proposed method. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Hochdynamische Materialeigenschaften von Ultrahochleistungsbeton (UHPC)
Authors: Nöldgen Markus , Millon Oliver , Thoma Klaus , Fehling Ekkehard
Published: October 2009

Der vorliegende Bericht liefert einen Beitrag zur Werkstoffbeschreibung von Ultrahochleistungsbetonen unter hochdynamischer Belastung. Grundlage für die Ermittlung der Werkstoffeigenschaften ist eine Hopkinson‐Bar Versuchsreihe, die Werte für die dynamische Zugfestigkeit, den dynamischen E‐Modul und die dynamische Bruchenergie unter Dehnraten von 102· s–1liefert. Ein Vergleich mit den Ergebnissen dieser Parameter für Normalbeton und hochfesten Betonen ermöglicht eine Einordnung des Ultrahochleistungsbetons in etablierte Ansätze und Berechnungsvorschriften und liefert einen Bewertungsansatz für die maßgebenden mechanischen Vorgänge. Unter Einbeziehung der Bruchenergie und der Spannungs‐Rissöffnungs‐Beziehung für UHPC in das RHT‐Betonmodell werden Hydrocode Simulationen durchgeführt, die den Versuch am Hopkinson‐Bar adäquat abbilden können.

Material Properties of Ultra High Performance Concrete (UHPC) at High Strain Rates

The presented paper is a contribution to the material description of Ultra High Performance Concrete (UHPC) under high‐speed dynamical loading conditions. Based on a series of Hopkinson‐Bar experiments dynamical material parameters such as the Tensile Strength, Young's Modulus and Fracture Energy are derived at high strain rates of 102· s–1. A comparison with the results of these parameters for normal and high strength concrete leads to a qualitative and quantitative evaluation of UHPC at high strain rates. With the extension of the established RHT material model for UHPC by the material's Fracture Energy and Stress‐Crack‐Opening‐Relation the Hopkinson‐Bar experiments are simulated appropriately.
Zur Querkraftgefährdung bestehender Spannbetonbrücken
Authors: Hegger Josef , Karakas Alexander , Pelke Eberhard , Schölch Udo
Published: October 2009

Zur Formulierung einer Handlungsanweisung werden in Teil I die geänderten Lastannahmen für Brücken nach DIN Fachbericht 101 mit den Belastungsklassen nach alten Normen verglichen und gezeigt, wie anhand aktueller Verkehrszahlen die Lastansätze modifiziert werden können. Der aktuelle Brückenbestand in Hessen wird mit der Straßeninformationsbank (Teilprojekt Bauwerksdaten) ausgewertet, um Klassifizierungs‐ und Bewertungskriterien zu erarbeiten. Zur Beurteilung des Querkraftwiderstandes werden die Grundlagen der Querkraftbemessung nach DIN 1045, DIN 4227, DIN Fachbericht 102 und aus der Literatur gegenübergestellt.

Shear‐Vulnerability of Existing Pre‐Stressed Concrete Bridges. Part One: Basics

In Part I, to formulate an operation directive the revised load assumptions for bridges of DIN Technical Report 101 are compared with the loading classes according to old standards and it is demonstrated, how the loading models can be modified based on actual traffic data. The current bridge asset in the Federal State of Hesse is evaluated using the “Road Information Database (Sub‐Project: Structural Data)” in order to work out classification and evaluation criteria. Regarding the assessment of the shear load‐bearing capacity the fundamentals of the shear load design models of DIN 1045, DIN 4227, DIN TR 102 and from the literature are compared.
Innovative Großbrücken im Eisenbahn‐Hochgeschwindigkeitsverkehr am Beispiel der Neubaustrecke Erfurt‐Leipzig/Halle
Authors: Schenkel Marcus , Marx Steffen , Krontal Ludolf
Published: October 2009

Eisenbahnbrücken, insbesondere im Hochgeschwindigkeitsbereich, müssen enormen funktionalen Anforderungen genügen. Gleichzeitig prägen gerade die großen Talbrücken der Neubaustrecken sehr stark die Landschaft, so dass neben den technischen Aspekten auch die gestalterischen Fragen einen sehr hohen Stellenwert haben. Auf der Eisenbahn‐Neubaustrecke zwischen Erfurt und Leipzig/Halle werden derzeitig mehrere Talbrücken nach neuen Entwurfskonzepten realisiert, welche die technischen und baukulturellen Ansprüche vereinen. In diesem einführenden Beitrag werden die außerordentlich vielschichtigen Rahmenbedingungen aus dem geltenden Regelwerk, dem Finanzierungs‐ sowie Vergaberecht und der hoheitlichen Bauaufsicht erläutert und die im Projekt erfolgte Umsetzung dargelegt. Ergänzend erfolgt beispielhaft eine Gegenüberstellung der ursprünglich geplanten und abschließend in die Realisierung geführten Bauwerksentwürfe der Scherkondetalbrücke und der Unstruttalbrücke. In nachfolgenden Aufsätzen ist geplant, die Entwurfskonzepte und die technischen Besonderheiten einzelner Brückenbauwerke der NBS Erfurt – Leipzig/Halle im Detail wiederzugeben.
Iron metabolism: microbes, mouse, and man
Authors: Latunde‐Dada Gladys O.
Published: October 2009

Recent advances in research on iron metabolism have revealed the identity of a number of genes, signal transduction pathways, and proteins involved in iron regulation in mammals. The emerging paradigm is a coordination of homeostasis within a network of classical iron metabolic pathways and other cellular processes such as cell differentiation, growth, inflammation, immunity, and a host of physiologic and pathologic conditions. Iron, immunity, and infection are intricately linked and their regulation is fundamental to the survival of mammals. The mutual dependence on iron by the host and invading pathogenic organisms elicits competition for the element during infection. While the host maintains mechanisms to utilize iron for its own metabolism exclusively, pathogenic organisms are armed with a myriad of strategies to circumvent these measures. This review explores iron metabolism in mammalian host, defense mechanisms against pathogenic microbes and the competitive devices of microbes for access to iron.
Synthetic cells and organelles: compartmentalization strategies
Authors: Roodbeen Renée , van Hest Jan C. M.
Published: October 2009

The recent development of RNA replicating protocells and capsules that enclose complex biosynthetic cascade reactions are encouraging signs that we are gradually getting better at mastering the complexity of biological systems. The road to truly cellular compartments is still very long, but concrete progress is being made. Compartmentalization is a crucial natural methodology to enable control over biological processes occurring within the living cell. In fact, compartmentalization has been considered by some theories to be instrumental in the creation of life. With the advancement of chemical biology, artificial compartments that can mimic the cell as a whole, or that can be regarded as cell organelles, have recently received much attention. The membrane between the inner and outer environment of the compartment has to meet specific requirements, such as semi‐permeability, to allow communication and molecular transport over the border. The membrane can either be built from natural constituents or from synthetic polymers, introducing robustness to the capsule.
Supporting the development of interactive applications in introductory programming courses
Authors: Aispuro Elvia E. , Licea Guillermo , Suárez Jaime , Sandoval Andrés , Carreño Mónica A. , Estrada Italia , Juárez‐Ramírez Reyes , Aguilar Leocundo , Martínez Luis G.
Published: October 2009

Extended Library for Visual Interactive Applications (ELVIA) is a programming tool developed and used by the two most important public universities in the Baja California peninsula in México. ELVIA provides a Java class framework that helps novice students of programming to automatically generate the graphical user interface of interactive applications, focusing in the classes and objects that compose the applications. This paper describes ELVIA, some application examples and experiences applying this programming tool in introductory programming courses. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 214–220, 2012
The strategy on replicate and similar web collections' detecting and clustering
Authors: Gao Kai
Published: October 2009

The fraction of the web collections consisting of duplicates has been surveyed at a high level. The quality of a web crawler increases if it can assess whether a newly crawled web page is a duplicate of a previously crawled page, so the strategy on detecting and filtering duplicates is important to improve the performance of search engine. This paper first presents the algorithm based on URL hashing to filter duplicates. On the basis of the Chinese key‐concepts weighting and extracting, this paper then proposes a method to cluster similar results based on content analysis. Both the experimental results and the application validate the feasibility of the approach as this can minimize the overlap while clustering similar results effectively. Some existing problems and further works are also present in the end. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 221–231, 2012
Determination of Residence Time Distribution in Gas‐Phase Microreactors using Light Emitting (Quasi‐)Continuous Plasma Discharges
Authors: Lohse S. , Michels A. , Tombrink S. , Agarl D. W. , Franzke J.
Published: October 2009

A novel technique for determining the residence time distribution in gas‐phase microreactors has been developed, which both minimizes flow distortions upon tracer injection and provides precise tracer detection with high temporal resolution. The methodology proposed has been demonstrated as a suitable means for characterizing gas‐phase microreactors by measurements on two idealized test reactors and two different ceramic plate microreactor modules.
Microreactor Process for the Optimized Synthesis of 5‐Hydroxymethylfurfural: A Promising Building Block Obtained by Catalytic Dehydration of Fructose
Authors: Tuercke T. , Panic S. , Loebbecke S.
Published: October 2009

A continuous microreaction process was set up to analyze and improve the “green” synthesis of 5‐hydroxymethylfurfural (5‐HMF) based on the HCl‐catalyzed dehydration of fructose in pure aqueous solutions. The process conditions were deliberately shifted to high temperatures and pressures (185 °C, 17 bar) and combined with a reduced reaction time of only 1 min to avoid extensive rehydration of the product. 5‐HMF was obtained with 75 % selectivity and 54 % yield at 71 % fructose conversion. In comparison to published data, a 24 % increase in selectivity and a 21 % increase in conversion could be achieved. Moreover, by adding organic co‐solvents and extraction agents to the reaction system, both 5‐HMF selectivity and yield could be further enhanced to 85 and 82 %, respectively. However, the use of additional organic solvents cannot be considered as a “green” process anymore.