bluuebunny/crossref_metadata_2025 huggingface dataset:
The origin of fibroblasts and mechanism of cardiac fibrosis
Authors: Krenning Guido , Zeisberg Elisabeth M. , Kalluri Raghu
Published: July 2010

Fibroblasts are at the heart of cardiac function and are the principal determinants of cardiac fibrosis. Nevertheless, cardiac fibroblasts remain poorly characterized in molecular terms. Evidence is evolving that the cardiac fibroblast is a highly heterogenic cell population, and that such heterogeneity is caused by the distinct origins of fibroblasts in the heart. Cardiac fibroblasts can derive either from resident fibroblasts, from endothelial cells via an endothelial–mesenchynmal transition or from bone marrow‐derived circulating progenitor cells, monocytes and fibrocytes. Here, we review the function and origin of fibroblasts in cardiac fibrosis.NB. The information given is correct. J. Cell. Physiol. 225: 631–637, 2010. © 2010 Wiley‐Liss, Inc.
A descriptive case series of patients with end‐stage liver disease hospitalized with variceal bleeding who received pharmacologic venous thromboembolism prophylaxis
Authors: Schleyer Anneliese M. , Smith Mark W. , Jarman Kenneth M. , Crane Paul K. , Schreuder Astrid B. , Goss J. Richard
Published: July 2010

BACKGROUND:

It is unknown whether venous thromboembolism prophylaxis (VTEP) should be utilized in hospitalized patients with end‐stage liver disease (ESLD), particularly in those admitted with variceal bleeding.

OBJECTIVE:

We sought to describe a cohort of patients who received pharmacologic VTEP, specifically identifying the occurrence of rebleeding.

DESIGN:

Descriptive case series.

SETTING/PATIENTS:

All adult patients with ESLD admitted to an urban county teaching hospital over three years with variceal bleeding who received pharmacologic VTEP during hospitalization.

RESULTS:

A total of 22 patients with ESLD and variceal bleeding received pharmacologic VTEP. Only 1 patient rebled after initiation of VTEP; 2 patients were diagnosed with lower extremity deep venous thrombosis while on VTEP including the 1 patient who rebled.

CONCLUSIONS:

VTEP was associated with an unexpectedly low incidence of recurrent bleeding in patients with ESLD and variceal bleeding. Further study may be warranted. Journal of Hospital Medicine 2010. © 2010 Society of Hospital Medicine.
An early viral response to standard interferon‐alpha identifies resistance to combination therapy with peginterferon and ribavirin in patients infected by HCV genotype 1
Authors: Toyoda Hidenori , Kumada Takashi , Kiriyama Seiki , Tanikawa Makoto , Hisanaga Yasuhiro , Kanamori Akira , Tada Toshifumi , Takagi Makiko , Hiramatsu Takeshi , Hosokawa Takanori , Arakawa Takahiro , Fujimori Masashi
Published: July 2010

As combination therapy with peginterferon (PEG‐IFN) and ribavirin has a high morbidity, identifying individuals with hepatitis C virus (HCV) who will not respond to the treatment would be beneficial. The early responses of serum HCV RNA levels to standard interferon (IFN) and PEG‐IFN were examined to determine if it was possible to identify resistance to combination therapy. One hundred thirty‐one patients infected with HCV genotype 1b were enrolled. Patients were given 6 MU of standard IFN alpha‐2b at least 2 weeks before initiating combination therapy. Serum HCV RNA levels were measured before, 24 hr after the administration of standard IFN, and 24 hr after the administration of PEG‐IFN (at the start of the combination therapy). The association between reductions in HCV RNA levels at 24 hr after the administration of standard IFN and PEG‐IFN and the outcome of combination therapy were analyzed. Reductions in HCV RNA levels were poorer in patients who did not respond than in those with a sustained virologic responses or relapses (P < 0.0001), both 24 hr after the administration of standard IFN and 24 hr after the administration of PEG‐IFN. Reductions in HCV RNA levels 24 hr after the administration of standard IFN were an independent factor associated with non‐response by multivariate analysis. An early reduction in viral load to a single administration of standard IFN is a useful predictor of non‐response in patients with HCV genotype 1, allowing for pretreatment identification of patients who will not benefit from combination therapy. J. Med. Virol. 82:1537–1544, 2010. © 2010 Wiley‐Liss, Inc.
Natural killer cells target HCV core proteins during the innate immune response in HCV transgenic mice
Authors: Satoh Kenichi , Takahashi Hiroki , Matsuda Chiho , Tanaka Toshiyuki , Miyasaka Masayuki , Zeniya Mikio , Kohara Michinori
Published: July 2010

The mechanism of the innate immune response to hepatitis C virus (HCV) has not been fully elucidated, largely due to the lack of an appropriate model. We used HCV transgenic (Tg) mice, which express core, E1, E2, and NS2 proteins regulated by the Cre/loxP switching expression system, to examine the innate immune response to HCV structural proteins. Twelve hours after HCV transgene expression, HCV core protein levels in Tg mouse livers were 15–47 pg/mg. In contrast, in Tg mice with a depletion of natural killer (NK) cells, we observed much higher levels of HCV core proteins (1,597 pg/ml). Cre‐mediated genomic DNA recombination efficiency in the HCV‐Tg mice was strongly observed in NK cell‐depleted mice between 0.5 and 1 day as compared to non‐treated mice. These data indicated that NK cells participate in the elimination of core‐expressing hepatocytes in the innate immune responses during the acute phase of HCV infection. J. Med. Virol. 82:1545–1553, 2010. © 2010 Wiley‐Liss, Inc.
High prevalence of hepatitis B virus genotype E in Northern Madagascar indicates a West‐African lineage
Authors: Dupinay Tatiana , Restorp Karin , Leutscher Peter , Rousset Dominique , Chemin Isabelle , Migliani Rene , Magnius Lars , Norder Heléne
Published: July 2010

The prevalence of hepatitis B virus (HBV) markers was investigated in 563 inhabitants aged 15–55 years from a sugar cane region, Sirama, and from a village, Mataipako, in Northern Madagascar. Serological markers of past or present infection were significantly higher in Sirama, 74% versus 45%. There was no difference in the prevalence of chronic HBsAg carriers, 8.7% versus 8.5% between the two regions. Sequencing the S gene in 45 strains revealed a predominance of genotype E, in 53%, followed by subgenotype A1 in 22%, and genotype D in 18%. Phylogenetic analyses of the genotype E strains showed homology with West African strains. All A1 isolates were similar to Malawi strains. Most genotype D strains were subgenotype D7 and related to strains from Somalia and Tunisia. One genotype D strain formed a branch between Pacific D4 and African D7 strains at neighbor‐joining analysis. The pre‐core stop mutant was found in 33% of the genotype D strains, 17% of E but not in any A1 strain. The high prevalence and low variability of genotype E strains in only two villages, indicates a rather recent introduction of this genotype into Madagascar from West Africa, possibly through migration or slave trade. The wider spread and genetic relationship of genotype D with East African and Austronesian strains indicate an earlier introduction of this genotype. Molecular epidemiology of HBV may thus be used to complement linguistic and genetic studies on past human migrations in Africa. J. Med. Virol. 82:1515–1526, 2010. © 2010 Wiley‐Liss, Inc.
Enterovirus markers and serum CXCL10 in children with type 1 diabetes
Authors: Berg Anna‐Karin , Tuvemo Torsten , Frisk Gun
Published: July 2010

Most patients with type 1 diabetes are considered to have a T‐cell mediated autoimmune disease. The chemokine CXCL10 promotes the migration of activated T‐cells. Virus infections might contribute to the pathogenesis of type 1 diabetes and enterovirus protein and/or genome have been detected in β‐cells from a majority of tested newly diagnosed children with type 1 diabetes. The chemokine CXCL10 is induced in human islet cells by enterovirus infections in vivo and in vitro, but is not expressed in islets from normal organ donors. Since CXCL10 is a chemokine known to be induced by virus infections and/or cellular damage, our aim was to study if levels of CXCL10 are elevated in serum from children with type 1 diabetes and whether it correlates to the presence of enterovirus markers. CXCL10, neutralizing antibody titer rises against certain enterovirus, and antibodies against GAD65 were measured in serum, and enterovirus PCR was performed on whole blood from 83 type 1 diabetes patients at onset, 48 siblings and 69 controls. CXCL10 was also measured in serum from 46 patients with proven enterovirus infection and in serum from 46 patients with other proven virus infections. The CXCL10 serum levels were not elevated in children at onset of type 1 diabetes and there was a considerable overlap between the groups with 99 (8–498) pg/ml in serum from children with type 1 diabetes, 120 (17–538) pg/ml in serum from controls, and 117 (7–448) pg/ml in siblings of the children with type 1 diabetes. The CXCL10 serum levels in patients with proven enterovirus infection were slightly increased compared to the levels in the other groups, 172 (0–585) pg/ml but there was no statistically significant difference. In contrast, CXCL10 serum levels in patients with other proven virus infections were clearly elevated 418 (34–611) pg/ml. Despite that elevated CXCL10 levels have been demonstrated in some groups of patients with type 1 diabetes, in this study the mean CXCL10 serum levels were not elevated in patients with type 1 diabetes neither in patients with proven enterovirus infection. In contrast, in patients with other virus infections the CXCL10 levels were elevated, presumably reflecting the severity or the site of infection. This suggests that local production of CXCL10 in the affected organ cannot be measured reproducible in serum and that its potential use in clinical practice is limited. J. Med. Virol. 82:1594–1599, 2010. © 2010 Wiley‐Liss, Inc.
Prevalence of antibodies to swine influenza viruses in humans with occupational exposure to pigs, Thuringia, Germany, 2008–2009
Authors: Krumbholz Andi , Lange Jeannette , Dürrwald Ralf , Hoyer Heike , Bengsch Stefan , Wutzler Peter , Zell Roland
Published: July 2010

The Eurasian lineages of swine influenza viruses are different genetically from classical swine H1N1 influenza viruses and comprise avian‐like H1N1 and human‐like H1N2 and H3N2 subtypes. Although sporadic isolation of such viruses from human specimens has been reported, the prevalence of human infections is not known. In the present study, the seroprevalence against Eurasian swine influenza viruses was investigated. Sera were collected in Thuringia, Germany, from December 2007 to April 2009. The study group comprised 118 professionals with occupational exposure to pigs (50 pig slaughterers/meat inspectors, 46 pig farmers, 22 veterinarians caring for pig herds). The control group included 118 age‐ and gender‐matched blood donors from Thuringia. As a result, 18 sera of the study group were identified with raised hemagglutination‐inhibition titers against a panel of nine swine influenza viruses (three strains/ subtype). For 17/18 sera this finding was confirmed in the neutralization assay. For 11/18 sera the raise of titers was significant, that is, a fourfold increase of hemagglutination‐inhibition titers was observed. No gender‐specific bias of the high titer sera was observed. Twelve sera of the control group showed increased hemagglutination‐inhibition titers against swine influenza viruses. Hemagglutination‐inhibition titers of 2/12 control sera were raised fourfold but did not exhibit a significant increase of neutralization titers. All increased hemagglutination‐inhibition titers of the control group may be explained by cross‐reactivity with seasonal influenza virus strains, as all these sera also reacted with human strains. J. Med. Virol. 82:1617–1625, 2010. © 2010 Wiley‐Liss, Inc.
Raman spectroscopy of selected borate minerals of the pinakiolité group
Authors: Frost Ray L.
Published: July 2010

The Raman spectra of a series of related minerals of the pinakiolité group have been collected and the spectra related to the mineral structure. These minerals are based upon an isolated BO33− ion. The site symmetry is reduced from D3h to C1. Intense Raman bands are observed for the minerals takeuchiité, pinakiolité, fredrikssonité and azoproité at 1084, 1086, 1086 and 1086 cm−1. These bands are assigned to the ν1 BO33− symmetric stretching mode. Low‐intensity Raman bands are observed for the minerals at 1345, 1748; 1435, 1748; 1435, 1750; and 1436, 1749 cm−1, respectively. One probable assignment is to ν3 BO33− antisymmetric stretching mode. Intense Raman bands of the studied minerals at 712 cm−1 are attributed to the ν2 out‐of‐plane bending mode. Importantly, through the comparison of the Raman spectra, the molecular structure of borate minerals with ill‐defined structures can be obtained. Copyright © 2010 John Wiley & Sons, Ltd.
Differential expression of Axl in hepatocellular carcinoma and correlation with tumor lymphatic metastasis
Authors: He Ling , Zhang Jianing , Jiang Lili , Jin Changgong , Zhao Yongfu , Yang Guang , Jia Li
Published: July 2010

Protein kinases play important roles in tumor development and progression. A variety of members of the signal transduction enzymes serve as targets for therapeutic intervention in cancer. The dysregulation of Axl receptor and its ligand growth arrest‐specific 6 (Gas6) is implicated in the pathogenesis of several cancers. In this study, the differential expressions of Axl were investigated in mouse hepatocarcinoma cell lines Hca‐F and Hca‐P, which have high‐ and low‐metastatic potential to lymph nodes. Experimental inhibition of Axl by siRNA assessed further the metastatic potential of Axl. The results showed that down‐regulation of Axl expression attenuated Hca‐F cells proliferation, migration, and invasion in vitro, as well as inhibited metastasis to peripheral lymph nodes in vivo. Further analysis demonstrated that the addition of exogenous Gas6 mediated the migration and invasion of Hca‐F cells both in vitro and in vivo through Axl. Furthermore, Gas6 stimulation of Axl in Hca‐F cells resulted primarily in the down‐regulation of Cyr61, a member of the CCN protein family involved in tumor progression. These data suggest that Axl acts as a tumor lymphatic metastasis‐associated gene, and may function partly through the regulation of Cyr61. © 2010 Wiley‐Liss, Inc.
A Hybrid Galerkin–Monte‐Carlo Approach to Higher‐Dimensional Population Balances in Polymerization Kinetics
Authors: Schütte Christof , Wulkow Michael
Published: July 2010

Population balance models describing not only the chain‐length distribution of a polymer but also additional properties like branching or composition are still difficult to solve numerically. For simulation of such systems two essentially different approaches are discussed in the literature: deterministic solvers based on rate equations and stochastic Monte‐Carlo (MC) strategies based on chemical master equations. The paper presents a novel hybrid approach to polymer reaction kinetics that combines the best of these two worlds. We discuss the theoretical conditions of the algorithm, describe its numerical realization, and show that, if applicable, it is more efficient than full‐scale MC approaches and leads to more detailed information in additional property indices than deterministic solvers.

magnified image
That I Won't Translate! Experiences of a Family Medical Interpreter in a Multicultural Environment
Authors: Seidelman Rhona D. , Bachner Yaacov G.
Published: July 2010

Family members used as patients' interpreters are a common occurrence in the medical environments of multicultural societies. It is recognized that the use of the family‐member interpreter may have some benefits. However, studies show that this option also has substantial disadvantages and therefore suggest that the use of professional medical interpreters is the preferable option for effective quality care. The purpose of the current study is to present the narrative of a family‐member interpreter in Israel, a diverse immigrant society. While numerous studies have been done on the challenges in the doctor‐interpreter‐patient medical encounter, these studies tend to focus on the experiences of the physicians or the patients, and the perspective of the interpreter is often sidelined. After discussing the various interpreting options, we suggest that the perspective of the family‐member interpreter strengthens assertions that professional interpretation is the best option for multilingual medical environments. Mt Sinai J Med 77:389–393, 2010. © 2010 Mount Sinai School of Medicine
Systems Pharmacology
Authors: Boran Aislyn D. W. , Iyengar Ravi
Published: July 2010

We examine how physiology and pathophysiology are studied from a systems perspective, using high‐throughput experiments and computational analysis of regulatory networks. We describe the integration of these analyses with pharmacology, which leads to new understanding of drug action and enables drug discovery for complex diseases. Network studies of drug‐target relationships can serve as an indication on the general trends in the approved drugs and the drug‐discovery progress. There is a growing number of targeted therapies approved and in the pipeline, which meets a new set of problems with efficacy and adverse effects. The pitfalls of these mechanistically based drugs are described, along with how a systems view of drug action is increasingly important to uncover intricate signaling mechanisms that play an important part in drug action, resistance mechanisms, and off‐target effects. Computational methodologies enable the classification of drugs according to their structures and to which proteins they bind. Recent studies have combined the structural analyses with analysis of regulatory networks to make predictions about the therapeutic effects of drugs for complex diseases and possible off‐target effects. Mt Sinai J Med 77:333–344, 2010. © 2010 Mount Sinai School of Medicine
Joseph's Wishes: Ethical Decision‐Making in Duchenne Muscular Dystrophy
Authors: Penner Leigh , Mollie Cantor Rabbi , Siegel Linda
Published: July 2010

The death of a child is an uncommon occurrence and can be difficult for families to accept. Attempts by the healthcare team to discuss end‐of‐life issues can be so upsetting to families that they refuse to participate in the discussion. Even with diseases where an early death can be anticipated, such as Duchenne muscular dystrophy, the family is often reluctant to discuss end‐of‐life issues when the patient is relatively healthy, preferring to focus on the current health issues. In this article we discuss what happens when there are disagreements between the patient and family and the needs of both must be taken into consideration. Mt Sinai J Med 77:394–397, 2010. © 2010 Mount Sinai School of Medicine
Überkritische Fluide zur Verwertung nachwachsender Rohstoffe
Authors: Vogel Herbert
Published: July 2010

Die Erschließung von Biomasse für die Chemikalien‐, Kunststoff‐ und Treibstoffproduktion ist eine der Zukunftsaufgaben der Industrienationen. Zur chemischen Umwandlung nachwachsender Rohstoffe, speziell von Kohlenhydraten in weniger funktionalisierte Zwischenprodukte (platform chemicals, building blocks), empfehlen sich Green Solvents in Form von überkritischen Fluiden; sie werden aber noch viel zu selten genutzt.
Eine neue leistungsfähige Dimension der Bildgebung
Authors: Daemi Sascha , Boese Matthias
Published: July 2010

Moderne Flächendetektoren machen die FT‐IR‐Mikroskopie zu einem neuen Bildgebungsverfahren. Auch größere Flächen sind innerhalb von Minuten bei sehr hoher Ortsauflösung zu vermessen. Ergebnisse lassen sich in leicht verständlichen Bildern auswerten.
Das neue GDCh‐Starter‐Kit für Studierende
Authors: Bengs Holger
Published: July 2010

Seit dem 1. Januar freuen sich in die Gesellschaft Deutscher Chemiker eintretende studentische Mitglieder über das neue GDCh‐Starter‐Kit für Studierende.
On sparse linear discriminant analysis algorithm for high‐dimensional data classification
Authors: Ng Michael K. , Liao Li‐Zhi , Zhang Leihong
Published: July 2010

In this paper, we present a sparse linear discriminant analysis (LDA) algorithm for high‐dimensional objects in subspaces. In high dimensional data, groups of objects often exist in subspaces rather than in the entire space. For example, in text data classification, groups of documents of different types are categorized by different subsets of terms. The terms for one group may not occur in the samples of other groups. In the new algorithm, we consider a LDA to calculate a weight for each dimension and use the weight values to identify the subsets of important dimensions in the discriminant vectors that categorize different groups. This is achieved by including the weight sparsity term in the objective function that is minimized in the LDA. We develop an iterative algorithm for computing such sparse and orthogonal vectors in the LDA. Experiments on real data sets have shown that the new algorithm can generate better classification results and identify relevant dimensions. Copyright © 2010 John Wiley & Sons, Ltd.
Nonoverlapping domain decomposition characteristic finite differences for three‐dimensional convection‐diffusion equations
Authors: Li Changfeng , Yuan Yirang
Published: July 2010

One domain decomposition method modified with characteristic differences is presented for non‐periodic three‐dimensional equations by multiply‐type quadratic interpolation and variant time‐step technique. This method consists of reduced‐scale, two‐dimensional computation on subdomain interface boundaries and fully implicit subdomain computation in parallel. A computational algorithm is outlined and an error estimate in discrete l2‐ norm is established by introducing new inner products and norms. Finally, numerical examples are given to illustrate the theoretical results, efficiency and parallelism of this method. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 28: 17‐37, 2012
The convergence of the bilinear and linear immersed finite element solutions to interface problems
Authors: He Xiaoming , Lin Tao , Lin Yanping
Published: July 2010

This article analyzes the error in both the bilinear and linear immersed finite element (IFE) solutions for second‐order elliptic boundary problems with discontinuous coefficients. The discontinuity in the coefficients is supposed to happen across general curves, but the mesh of the IFE methods can be allowed not to align with the curve of discontinuity. It has been shown that the bilinear and linear IFE solutions converge to the exact solution under the usual assumptions about the meshes and regularity.© 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 28: 312–330 2012
A posteriori boundary control for FEM approximation of elliptic eigenvalue problems
Authors: da Veiga L. Beirão , Verani M.
Published: July 2010

We derive new a posteriori error estimates for the finite element solution of an elliptic eigenvalue problem, which take into account also the effects of the polygonal approximation of the domain. This suggests local error indicators that can be used to drive a procedure handling the mesh refinement together with the approximation of the domain. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 28: 369–388, 2012
Optimization of organo‐layered double hydroxide dispersion in LDPE‐based nanocomposites
Authors: Coiai Serena , Scatto Marco , Conzatti Lucia , Azzurri Fiorenza , Andreotti Leonardo , Salmini Elena , Stagnaro Paola , Zanolin Alessandro , Cicogna Francesca , Passaglia Elisa
Published: July 2010

Low‐density polyethylene/layered double hydroxide (LDPE/LDH) nanocomposites were prepared via melt extrusion using organo‐LDH particles and maleic anhydride functionalized polyethylene as compatibilizer. Processing parameters, preparation method, and feed composition were properly modulated until obtaining nanocomposites with intercalated/exfoliated morphologies, and an uniform distribution of nanolayers, as evidenced by X‐ray diffraction and transmission electron microscopy analysis. These materials showed a significant improvement of the thermal‐oxidative stability, which increased of about 50°C during the first step of the degradation process. Moreover, a remarkable reduction of the oxygen permeability, proportional to the aspect ratio of LDH stacks dispersed in the polyolefin matrix was evidenced, indicating the possible application of nanocomposite films as food packaging materials. As highlighted by dynamic mechanical thermal analysis, interactions at the interface between LDH layers and polymer chains caused a shift of the LDPE β‐relaxation toward higher temperatures and a reduction of the peak intensity with respect to the matrix. It was also found that the storage modulus of the nanocomposites was lower in all the temperature range with respect to the reference samples. Finally, on‐line capillary rheometer measurements evidenced that the shear thinning behavior of the nanocomposites was dominated by the matrix so that the melt processability was not compromised by the presence of the filler. Copyright © 2010 John Wiley & Sons, Ltd.
Long‐term performance degradation of various kinds of photovoltaic modules under moderate climatic conditions
Authors: Ishii Tetsuyuki , Takashima Takumi , Otani Kenji
Published: July 2010

Various kinds of photovoltaic (PV) modules have been developed and practically operated as PV systems up to present. Investigation of the long‐term reliability of PV modules is indispensable for the use of PV systems as reliable energy sources. In this study, we show the results of outdoor exposure test in which the performance of 14 PV modules composed of five different kinds made by six different PV manufacturers have been measured since July 2004. The average performance is calculated in each year from 2005 to 2008, and the performance degradation is quantitatively evaluated. The results are that the magnitude of the performance degradation can be clearly classified by the kinds of the PV modules. The performance difference of the single‐crystalline silicon (sc‐Si) modules between 2005 and 2008 is from 1.9% to 2.8%. Polycrystalline silicon (pc‐Si) modules show performance degradation from 0.7% to 1.4%. The performance of an amorphous silicon/crystalline silicon (a‐Si:H/c‐Si) decreased by 0.7%. Although a pair of a‐Si modules had been already exposed to sunlight for about 6 months, the pair of modules show 4.4% of performance degradation. More than half of the performance degradation happened during the initial period from 2005 to 2006. This indicates that it takes about 2 years until the performance of a‐Si modules is stable. The performance is quite stable after 2006. Interestingly, the performance of the cupper indium gallium diselenide modules in 2008 is about 0.8% higher than that in 2005. Copyright © 2010 John Wiley & Sons, Ltd.
Plasmonic light‐trapping for Si solar cells using self‐assembled, Ag nanoparticles
Authors: Beck F. J. , Mokkapati S. , Catchpole K. R.
Published: July 2010

We present experimental results for photocurrent enhancements in thin c‐Si solar cells due to light‐trapping by self‐assembled, random Ag nanoparticle arrays. The experimental geometry is chosen to maximise the enhancement provided by employing previously reported design considerations for plasmonic light‐trapping. The particles are located on the rear of the cells, decoupling light‐trapping and anti‐reflection effects, and the scattering resonances of the particles are red‐shifted to target spectral regions which are poorly absorbed in Si, by over‐coating with TiO2. We report a relative increase in photocurrent of 10% for 22 µm Si cells due to light‐trapping. Incorporation of a detached mirror behind the nanoparticles increases the photocurrent enhancement to 13% and improves the external quantum efficiency by a factor of 5.6 for weakly absorbed light. Copyright © 2010 John Wiley & Sons, Ltd.
Add‐on laser tailored selective emitter solar cells
Authors: Röder T. C. , Eisele S. J. , Grabitz P. , Wagner C. , Kulushich G. , Köhler J. R. , Werner J. H.
Published: July 2010

An elegant laser tailoring add‐on process for silicon solar cells, leading to selectively doped emitters increases their efficiency η by Δη = 0.5% absolute. Our patented, scanned laser doping add‐on process locally increases the doping under the front side metallization, thus allowing for shallow doping and less Auger recombination between the contacts. The selective laser add‐on process modifies the emitter profile from a shallow error‐function type to Gaussian type and enables excellent contact formation by screen printing, normally difficult to achieve for shallow diffused emitters. The significantly deeper doping profile of the laser irradiated samples widens the process window for the firing of screen printed contacts and avoids metal spiking through the pn‐junction. Copyright © 2010 John Wiley & Sons, Ltd.
Characterization of polycrystalline silicon wafers for solar cells sliced with novel fixed‐abrasive wire
Authors: Watanabe N. , Kondo Y. , Ide D. , Matsuki T. , Takato H. , Sakata I.
Published: July 2010

For slicing crystalline silicon ingots, we have developed a novel fixed‐abrasive wire where diamond grit is fixed onto a bare wire by resin bonding. The properties of the wafers sliced using a multi‐wire saw with the fixed‐abrasive wire have been investigated. When compared with the wafers sliced with the loose‐abrasive wire, the slicing speed is improved by approximately 2.5‐fold and the thicknesses of saw‐damage layers are reduced by more than a factor of two. Polycrystalline silicon solar cells have been fabricated for the first time utilizing the wafers sliced with the fixed‐abrasive wire, and the cells with the saw‐damage etching depth of 7 µm have shown photovoltaic properties comparable to those prepared using the wafers sliced with the loose‐abrasive wire and subsequently etched to remove the damage layers up to 15 µm. It has been clarified that wafer slicing using the fixed‐abrasive wire is promising as a next‐generation slicing technique for fabrication of solar cells, particularly thin silicon cells where the wafer thicknesses approach or become less than 150 µm. Copyright © 2010 John Wiley & Sons, Ltd.
Comparative life‐cycle energy payback analysis of multi‐junction a‐SiGe and nanocrystalline/a‐Si modules
Authors: Kim H.C. , Fthenakis V.M.
Published: July 2010

Despite the publicity of nanotechnologies in high tech industries including the photovoltaic sector, their life‐cycle energy use and related environmental impacts are understood only to a limited degree as their production is mostly immature. We investigated the life‐cycle energy implications of amorphous silicon (a‐Si) PV designs using a nanocrystalline silicon (nc‐Si) bottom layer in the context of a comparative, prospective life‐cycle analysis framework. Three R&D options using nc‐Si bottom layer were evaluated and compared to the current triple‐junction a‐Si design, i.e., a‐Si/a‐SiGe/a‐SiGe. The life‐cycle energy demand to deposit nc‐Si was estimated from parametric analyses of film thickness, deposition rate, precursor gas usage, and power for generating gas plasma. We found that extended deposition time and increased gas usages associated to the relatively high thickness of nc‐Si lead to a larger primary energy demand for the nc‐Si bottom layer designs, than the current triple‐junction a‐Si. Assuming an 8% conversion efficiency, the energy payback time of those R&D designs will be 0.7–0.9 years, close to that of currently commercial triple‐junction a‐Si design, 0.8 years. Future scenario analyses show that if nc‐Si film is deposited at a higher rate (i.e., 2–3 nm/s), and at the same time the conversion efficiency reaches 10%, the energy‐payback time could drop by 30%. Copyright © 2010 John Wiley & Sons, Ltd.
Different radical initiation techniques of hydrosilylation reactions of multiple bonds in water: thermal and photochemical initiation
Authors: Calandra Julia , Postigo Al , Russo Diana , Nudelman Norma Sbarbati , Tereñas Juan José
Published: July 2010

The classical radical‐based hydrosilylation reaction of organic compounds bearing CC multiple bonds is usually carried out in organic solvents and is herein presented in water with both hydrophobic and hydrophilic substrates. Thermal and photochemical initiations are used to accomplish the radical‐induced hydrosilylation reaction of CC multiple bonds in water with tris(trimethylsilyl)silane ((Me3Si)3SiH). Photochemical radical initiation in the absence of a chemical radical precursor other than the silane is found to be a very efficient and convenient method to induce the hydrosilylation reaction of CC multiple bonds of organic compounds with (Me3Si)3SiH in water. This new alternate radical‐based methodology studied in water is confronted with the classical radical thermal initiation of hydrosilylation reactions triggered through the thermal decomposition of azo compounds. Copyright © 2010 John Wiley & Sons, Ltd.
The polarisability potential as a steric index
Authors: Camacho Cristopher , Mata‐Segreda Julio F.
Published: July 2010

The acid‐catalysed hydrolysis of carboxylic esters is the reference chemical reaction used for the empirical evaluation of steric effects. In this work, the polarisability potential (Hehre, et al., J. Am. Chem. Soc. 1986, 108, 1711–1712) is identified as quantum‐mechanical size of substituent groups. Correlation is found between this quantity and reactivity features of the reference reaction. Copyright © 2010 John Wiley & Sons, Ltd.
Synthesis and characterization of nitrogen‐linked carbazole‐containing fluorescent polymers
Authors: Takagi Koji , Takao Hidenobu , Nakagawa Tsuyoshi
Published: July 2010

We have prepared four light‐emitting polymers bearing a chromophore composed of carbazole and fluorene by the Suzuki coupling polycondensation. Two nonconjugated polymers (P3CzBFXy and P2CzFXy) had a chromophore tethered by the p‐xylylene spacer, whose connection point between carbazole and fluorene in addition to the number of fluorene unit was systematically changed to investigate the emission wavelength and intensity. The red‐shifted absorption and emission maximum wavelengths together with the improved fluorescence quantum yield of polymers P3CzBFXy and P2CzFXy indicate that the increment of the number of para‐connected benzene rings included in the chromophore effectively extends the conjugation length. The fact that polymer P3CzBFXy has longer wavelength absorption and emission spectra also indicates the interaction of the carbazole nitrogen lone pair with the oligophenylene moiety. Other two polymers P3CzFPy and P3CzFPym having the heterocycle directly bound to the carbazole nitrogen were prepared to know the character of the carbazole nitrogen lone pair and their influence on the fluorescence behavior. The fluorescence spectra of polymer P3CzFPym bearing the pyrimidine ring gradually red‐shifted in conjunction with the decrease of fluorescence quantum yield on going from toluene solution to CHCl3 solution because of the intramolecular charge transfer at the excited state. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3729–3735, 2010
Synthesis and characterization of functionalized water soluble cationic poly(ester amide)s
Authors: Pang Xuan , Wu Jun , Reinhart‐King Cynthia , Chu Chih‐Chang
Published: July 2010

A new family of positively charged, water soluble and functional amino acid‐based poly(ester amide)s (Arg‐AG PEA) consisting of four building blocks (L‐Arginine, DL‐2‐Allylglycine, oligoethylene glycol, and aliphatic diacid) were synthesized by the solution copolycondensation. Functional pendant carbon–carbon double bonds located in the DL‐2‐allylglycine unit were incorporated into these Arg‐AG PEAs, and the double bond contents could be adjusted by tuning the feed ratio of L‐arginine to DL‐2‐allylglycine monomers. Chemical structures of this new functional Arg‐AG PEA family were confirmed by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) spectra. The thermal property of these polymers was investigated; increasing the methylene chain in both the amino acid and diacid segments resulted in a reduction in the polymer glass‐transition temperature. All these cationic Arg‐AG PEAs had good solubility in water and polar organic solvents. The cytotoxity of Arg‐AG PEAs was evaluated by 3‐(4,5‐Dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay. These preliminary MTT results indicated that Arg‐AG PEAs were nontoxic to bovine aortic endothelial cells (BAECs). © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3758–3766, 2010
Synthesis and application of molybdenum (III) complexes bearing weakly coordinating anions as catalysts of isobutylene polymerization
Authors: Diebl Bernd E. , Li Yang , Cokoja Mirza , Kühn Fritz E. , Radhakrishnan Narayanan , Zschoche Stefan , Komber Hartmut , Yeong Hui Yee , Voit Brigitte , Nuyken Oskar , Hanefeld Phillip , Walter Hans‐Michael
Published: July 2010

Acetonitrile ligated molybdenum (III) complexes of the structure [MoCl(NCCH3)5]2+ bearing different weakly coordinating anions [B(C6F5)4]− (WCA a), [B{C6H3(m‐CF3)2}4]− (WCA b) and [(C6F5)3B‐C3H3N2‐B(C6F5)3]− (WCA c) were applied as homogeneous catalysts of the polymerization of isobutylene. High monomer conversions were obtained in short reaction times (<30 min). The molecular weight of the resulting polyisobutylene is nearly independent of parameters such as temperature, solvent, monomer concentration, but is strongly influenced by the type of WCA and by chain transfer reactions which were observed in these systems. Highly reactive low molecular weight polyisobutylenes (Mn < 2000 g/mol) were obtained with a high content of exo double bond end groups as shown by 1H NMR analysis. Furthermore, experiments were performed to reduce the isomerization of these exo end groups into other internal double bonds by varying the polymerization parameters. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3775–3786, 2010
Synthesis of an amphiphilic polymer having hydrophobic acetal and hydrophilic pyrrolidone moieties and its application to persisting release of aldehyde as a pro‐fragrance
Authors: Wang Yanmei , Morinaga Hisatoyo , Sudo Atsushi , Endo Takeshi
Published: July 2010

A polymer having acetal moiety in the side chain was synthesized by a reaction of 1,3‐diol structure of poly(vinyl alcohol‐co‐N‐vinylpyrrolidone) and octanal. The hydrophobicity of the resulting acetal moiety and the hydrophilicity of the pyrrolidone moiety allowed the polymer to exhibit amphiphilicity. The polymer released octanal by hydrolysis of the acetal side chains under acidic conditions. The release of octanal was enhanced by the increased hydrophilicity of the polymer because of the presence of pyrrolidone moiety. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3816–3822, 2010
Synthesis of heterocyclic monomers via Reissert chemistry
Authors: Gibson Harry W. , Brumfield Kimberly K. , Grisle Roger A. , Hermann Christine K. F.
Published: July 2010

The chemistry of Reissert compounds has been used to synthesize activated difluorotetraketone monomers containing two coupled isoquinolyl moieties, linked at either the 1,1′‐ or 4,4′‐positions. These monomers offer routes to novel families of poly(heteroarylene ether)s. New 4,4′‐coupled bis(Reissert compound) 9 containing 4,4′‐diketo moieties failed to afford the desired difluorotetraketo monomer upon attempted rearrangement. However, analogous bis(Reissert compound) 19 containing 4,4′‐dibenzyl units did so, via aldehyde condensation, hydrolysis of the intermediate ester and oxidation of the four benzylic moieties to keto groups; thus the novel difluorotetraketone monomer 10 was prepared. Novel bis(Reissert compound)s 24, 28, and 35 were synthesized from diacid chlorides and 4‐(p‐fluorobenzyl)isoquinoline. Rearrangement of 24 to the diketone 29, followed by oxidation of the 4‐benzyl moieties resulted in difluorotetraketone monomer 30 containing a 1,1′‐linked bisisoquinoline. The 1,1′‐linked bis(isoquinolylfluorodiketo) monomer 38, isomeric with 10, was prepared from 4‐(p‐fluorobenzyl) Reissert compound 36 by condensation with terephthaldehyde, ester hydrolysis to diol 37, and oxidation. In the course of this effort, a number of new isoquinoline Reissert compounds were synthesized as model systems. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3856–3867, 2010
Photo‐crosslinked fluorinated thin films from azido‐functionalized random copolymers
Authors: Al Akhrass Samer , Damiron Denis , Carrot Géraldine , Drockenmuller Eric
Published: July 2010

Random copolymers of styrene, p‐azidomethylstyrene and 1H,1H,2H,2H‐perfluorodecyl methacrylate were prepared in two steps involving nitroxide‐mediated radical copolymerization and azidation reaction and further characterized by 1H and 19F NMR, size exclusion chromatography, differential scanning calorimetry, and thermal gravimetric analysis. Ultrathin films of these azidomethyl‐functionalized fluorinated random copolymers, with thicknesses ranging from 20 to 100 nm, were spin coated onto Si substrates and then crosslinked by ultraviolet irradiation resulting in smooth and insoluble crosslinked fluorinated polymer mats. The surface properties of the supported thin films were investigated by X‐ray photoelectron spectroscopy and water contact angle measurements. These tailored photo‐crosslinked coatings afford a versatile control and homogenization of the wetting properties of different organic and inorganic substrates. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3888–3895, 2010
(2‐Hydroxy isobutyric) acid containing poly(glycolic acid): Structure–properties relationship
Authors: Soccio Michelina , Lotti Nadia , Finelli Lara , Gazzano Massimo , Munari Andrea
Published: July 2010

Poly(glycolic acid) (PGA) and a series of novel random copolymers of PGA containing 2‐hydroxyisobutyrric acid (PGAPHIB) (HIB unit content from 1.5 to 7.4 mol %) were synthesized and characterized in terms of chemical structure and molecular weight. Afterward, the polyesters were examined by thermogravimetric analysis, differential scanning calorimetry, and X‐ray diffraction techniques. The copolymers, which displayed a better thermal stability than PGA, at room temperature appeared as semicrystalline materials: the main effect of copolymerization was a lowering in the amount of crystallinity and a decrease of the melting temperature with respect to homopolymer PGA. Baur's equation described well the Tm‐composition data. X‐ray diffraction measurements allowed the identification of the PGA crystalline structure in all cases. After melt quenching, semicrystalline samples were obtained with the exception of PGAPHIB7.4 copolymer. The introduction of HIB units decreased the crystallization rate compared with pure PGA. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1901–1910, 2010
Bound fractions of methacrylate polymers adsorbed on silica using FTIR
Authors: Krisanangkura Piyawan , Packard Alyssa M. , Burgher Jacqueline , Blum Frank D.
Published: July 2010

The H‐bonding of carbonyl groups on a series of methacrylate polymers with silanols on fumed silica was studied with transmission FTIR. The set included poly(alkyl methacrylates) with alkyl groups, (n‐CnH2n+1) of n = 1, 2, 4, and 12 and poly(benzyl methacrylate). Shifts in the vibrational frequencies for bound carbonyl groups (of ∼20 cm−1 lower than those found in the bulk) were observed in the adsorbed polymer samples. A series of samples with different adsorbed amounts (varying from 0.5 to 2.0 mg m−2) of each polymer was prepared to determine the effect of the side chain on the H‐bonding. The fractions of bound carbonyls, p, for each of the methacrylate polymers studied, were calculated from a model based on the ratios of the absorption coefficients of the bound to free carbonyl resonances, X (= αb/αf). The X values were determined from linear regressions of the ratios of the free to bound carbonyl intensities as a function of the amounts of adsorbed polymer, Mt. The bound fractions, p, were observed to decrease with increase in adsorbed amounts and with increase in the lengths of the side chains of the methacrylate polymers, except for poly(lauryl methacrylate) (PLMA). PLMA has a very low glass transition temperature (Tg) and is likely rubbery on the surface, whereas the other polymers are likely glassy at ambient temperature. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1911–1918, 2010
Automated ‘X‐Y’ robot for peptide synthesis with microwave heating: application to difficult peptide sequences and protein domains
Authors: Malik Leila , Tofteng A. Pernille , Pedersen Søren L. , Sørensen Kasper K. , Jensen Knud J.
Published: July 2010

Precise microwave heating has emerged as a valuable method to aid solid‐phase peptide synthesis (SPPS). New methods and reliable protocols, as well as their embodiment in automated instruments, are required to fully use this potential. Here we describe a new automated robotic instrument for SPPS with microwave heating, report protocols for its reliable use and report the application to the synthesis of long sequences, including the β‐amyloid 1‐42 peptide. The instrument is built around a valve‐free robot originally developed for parallel peptide synthesis, where the robotic arm transports reagents instead of pumping reagents via valves. This is the first example of an ‘X‐Y’ robotic microwave‐assisted synthesizer developed for the assembly of long peptides. Although the instrument maintains its capability for parallel synthesis at room temperature, in this paper, we focus on sequential peptide synthesis with microwave heating. With this valve‐free instrument and the protocols developed for its use, fast and efficient syntheses of long and difficult peptide sequences were achieved. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Phase II monitoring of multivariate multiple linear regression profiles
Authors: Eyvazian M. , Noorossana R. , Saghaei Abbas , Amiri Amirhossein
Published: July 2010

In certain cases, the quality of a process or a product can be effectively characterized by two or more multiple linear regression profiles in which response variables are correlated. This structure can be modeled as multivariate multiple linear regression profiles. When linear profiles are monitored separately, then correlation between response variables is ignored and misleading results could be expected. To overcome this problem, the use of methods that consider the multivariate structure between response variables is inevitable. In this paper, we propose four methods to monitor this structure in Phase II. The performance of the methods is compared through simulation studies in terms of the average run length criterion. Furthermore, a method based on likelihood ratio approach is developed to determine the location of shifts and a numerical simulation is used to evaluate the performance of the proposed method. Finally, the use of the methods is illustrated by a numerical example. Copyright © 2010 John Wiley & Sons, Ltd.
Optimal process adjustment by integrating production data and design of experiments
Authors: Li Jing , Xie Hairong , Jin Jionghua
Published: July 2010

This paper proposes a method to improve the process model estimation based on limited experimental data by making use of abundant production data and to achieve the optimal process adjustment based on the improved process model. The proposed method is called an Estimation‐adjustment (EA) method. Furthermore, this paper proves three properties associated with the EA, which guarantee the feasibility and effectiveness of using EA for integrating production and experimental data for optimal process adjustment. Also, the paper develops a sequential hypothesis testing procedure for implementing the EA. The properties and implementation of the EA are demonstrated in a cotton spinning process. Copyright © 2010 John Wiley & Sons, Ltd.