bluuebunny/crossref_metadata_2025 huggingface dataset:
Siglec-G Deficiency Leads to More Severe Collagen-Induced Arthritis and Earlier Onset of Lupus-like Symptoms in MRL/lpr Mice
Authors: Bökers Susanne , Urbat Anne , Daniel Christoph , Amann Kerstin , Smith Kenneth G. C. , Espéli Marion , Nitschke Lars
Published: March 2014

Siglec-G is a member of the sialic acid–binding Ig-like lectin (Siglec) family expressed on all B cells. Siglec-G–deficient mice show a large expansion of the B1 cell compartment, demonstrating the crucial role of Siglec-G as an inhibitory receptor on this cellular subset. Although Siglec-G–deficient mice did not develop spontaneous autoimmunity, mice double-deficient for Siglec-G and the related Siglec protein CD22 did show autoimmunity at an older age. In this study, we addressed the question of whether loss of Siglec G on its own affects disease severity in animal models of rheumatoid arthritis and systemic lupus erythematosus. Siglec-G–deficient mice showed moderately increased clinical severity and higher inflammation of the knee joints following collagen-induced arthritis, when compared with control mice. The Siglec-G–deficient mouse was also backcrossed to the autoimmune prone MLR/lpr background. Although both Siglec-G–deficient and control MRL/lpr mice developed a lupus-like disease, Siglec-G–deficient MRL/lpr mice showed an earlier occurrence of autoantibodies; a higher lymphoproliferation of B and T cells; and an earlier onset of disease, as shown by proteinuria and glomerular damage in the kidney. Moreover, Siglec-G–deficient female mice showed a significantly reduced survival compared with female control MRL/lpr mice. Thus, the loss of the inhibitory receptor Siglec-G led to a moderate exacerbation of disease severity and early onset in both collagen-induced arthritis and spontaneous lupus nephritis in MRL/lpr mice.
Evaluation of temporal difference limen in preoperative non-invasive ear canal audiometry as a predictive factor for speech perception after cochlear implantation
Authors: Sinkkonen Saku T. , Kronlund Lars , Hautamäki Johannes , Jero Jussi , Aarnisalo Antti A. , Kentala Erna
Published: March 2014

The temporal difference limen (TDL) can be measured with noninvasive electrical ear canal stimulation. The objective of the study wa to determine the role of preoperative TDL measurements in predicting patients’ speech perception after cochlear implantation. We carried out a retrospective chart analysis of fifty-four cochlear implant (CI) patients with preoperative TDL and postoperative bisyllabic word recognition measurements in Helsinki University Central Hospital between March 1994 and March 2011. Our results show that there is no correlation between TDL and postoperative speech perception. However, patient’s advancing age correlates with longer TDL but notdirectly with poorer speech perception. The results are in line with previous results concerning the lack of predictive value of preoperativ TDL measurements in CI patients.
Galois theory of quadratic rational functions
Authors: Jones Rafe , Manes Michelle
Published: March 2014

For a number field

K

with absolute Galois group

G_K

, we consider the action of

G_K

on the infinite tree of preimages of

\alpha \in K

under a degree-two rational function

\phi \in K(x)

, with particular attention to the case when

\phi

commutes with a non-trivial Möbius transformation. In a sense this is a dynamical systems analogue to the

\ell

-adic Galois representation attached to an elliptic curve, with particular attention to the CM case. Using a result about the discriminants of numerators of iterates of

\phi

, we give a criterion for the image of the action to be as large as possible. This criterion is in terms of the arithmetic of the forward orbits of the two critical points of

\phi

. In the case where

\phi

commutes with a non-trivial Möbius transformation, there is in effect only one critical orbit, and we give a modified version of our maximality criterion. We prove a Serre-type finite-index result in many cases of this latter setting.
New York's Subterranean Paradoxes: A Review Of Subway
Authors: Merrill Samuel
Published: March 2014

This review considers the recent re-publication of Bruce Davidson’s Subway series of photographs, and their exhibition at C/O in Berlin, Germany. As such, this review positions Davidson’s photographs both in relation to wider cultural analyses that highlight the paradoxical nature of subterranean space, and within a selective genealogy of subway representations. Furthermore, it views the reinvigorated interest in Davidson’s work to be reflective of the growing popularity of subterranean space that has recently re-emphasised its cultural potential.
Culturally Competent Transplant Program Improves Hispanics' Knowledge and Attitudes about Live Kidney Donation and Transplant
Authors: Gordon Elisa J. , Reddy Elizabeth , Gil Sorelly , Feinglass Joseph , Rodde Jillian , Abecassis Michael M. , Caicedo Juan Carlos
Published: March 2014

Context

Hispanics receive disproportionately fewer live donor kidney transplants than non-Hispanic whites. Increasing Hispanics' knowledge and changing attitudes about live kidney donation may reduce these disparities.

Objective

To evaluate the effectiveness of culturally and linguistically competent educational sessions delivered through Northwestern University's Hispanic Transplant Program.

Design

Baseline and postsession questionnaires were used to evaluate changes in patients' and family members' knowledge and attitudes toward live kidney donation and program satisfaction. Knowledge items related to live kidney donation were scaled, and changes in scores were evaluated via a paired t test. Multiple regression analysis of follow-up knowledge scores controlled for baseline scores was used to estimate the effects of patients' and families' sociodemographic characteristics. Changes in attitude items, including comfort with exploring live kidney donation, were analyzed with χ2 tests.

Results

One-hundred thirteen patients and family members completed surveys before and after an education session. Respondents' knowledge about live kidney donation and transplant increased significantly ( P < .001) between baseline and after the session. Patients' attitudes toward live kidney donation became more favorable ( P < .02), as did family members' attitudes toward being a donor ( P < .001) after participating in the program. All respondents reported high levels of satisfaction with the program and preferences for culturally congruent care.

Conclusions

The educational sessions provided by the Hispanic Transplant Program effectively addressed commonly shared Hispanic concerns about live kidney donation. Culturally congruent education increased Hispanic patients' and family members' knowledge and improved attitudes about live donor kidney transplants.
Crustal thickness and velocity structure across the Moroccan Atlas from long offset wide‐angle reflection seismic data: The SIMA experiment
Authors: Ayarza P. , Carbonell R. , Teixell A. , Palomeras I. , Martí D. , Kchikach A. , Harnafi M. , Levander A. , Gallart J. , Arboleya M. L. , Alcalde J. , Fernández M. , Charroud M. , Amrhar M.
Published: March 2014

The crustal structure and topography of the Moho boundary beneath the Atlas Mountains of Morocco has been constrained by a controlled source, wide‐angle seismic reflection transect: the SIMA experiment. This paper presents the first results of this project, consisting of an almost 700 km long, high‐resolution seismic profile acquired from the Sahara craton across the High and the Middle Atlas and the Rif Mountains. The interpretation of this seismic data set is based on forward modeling by raytracing, and has resulted in a detailed crustal structure and velocity model for the Atlas Mountains. Results indicate that the High Atlas features a moderate crustal thickness, with the Moho located at a minimum depth of 35 km to the S and at around 31 km to the N, in the Middle Atlas. Upper crustal shortening is resolved at depth through a crustal root where the Saharan crust underthrusts the northern Moroccan crust. This feature defines a lower crust imbrication that, locally, places the Moho boundary at ∼40–41 km depth in the northern part of the High Atlas. The P‐wave velocity model is characterized by relatively low velocities, mostly in the lower crust and upper mantle, when compared to other active orogens and continental regions. These low deep crustal velocities together with other geophysical observables such as conductivity estimates derived from MT measurements, moderate Bouguer gravity anomaly, high heat flow, and surface exposures of recent alkaline volcanism lead to a model where partial melts are currently emplaced at deep crustal levels and in the upper mantle. The resulting model supports the existence of a mantle upwelling as mechanism that would contribute significantly to sustain the High Atlas topography. However, the detailed Moho geometry deduced in this work should lead to a revision of the exact geometry and position of this mantle feature and will require new modeling efforts.
Three‐dimensional imaging of subsurface structural patterns using quantitative large‐scale multiconfiguration electromagnetic induction data
Authors: von Hebel Christian , Rudolph Sebastian , Mester Achim , Huisman Johan A. , Kumbhar Pramod , Vereecken Harry , van der Kruk Jan
Published: March 2014

Electromagnetic induction (EMI) systems measure the soil apparent electrical conductivity (ECa), which is related to the soil water content, texture, and salinity changes. Large‐scale EMI measurements often show relevant areal ECa patterns, but only few researchers have attempted to resolve vertical changes in electrical conductivity that in principle can be obtained using multiconfiguration EMI devices. In this work, we show that EMI measurements can be used to determine the lateral and vertical distribution of the electrical conductivity at the field scale and beyond. Processed ECa data for six coil configurations measured at the Selhausen (Germany) test site were calibrated using inverted electrical resistivity tomography (ERT) data from a short transect with a high ECa range, and regridded using a nearest neighbor interpolation. The quantitative ECa data at each grid node were inverted using a novel three‐layer inversion that uses the shuffled complex evolution (SCE) optimization and a Maxwell‐based electromagnetic forward model. The obtained 1‐D results were stitched together to form a 3‐D subsurface electrical conductivity model that showed smoothly varying electrical conductivities and layer thicknesses, indicating the stability of the inversion. The obtained electrical conductivity distributions were validated with low‐resolution grain size distribution maps and two 120 m long ERT transects that confirmed the obtained lateral and vertical large‐scale electrical conductivity patterns. Observed differences in the EMI and ERT inversion results were attributed to differences in soil water content between acquisition days. These findings indicate that EMI inversions can be used to infer hydrologically active layers.
Towards High Efficiency and Low Roll‐Off Orange Electrophosphorescent Devices by Fine Tuning Singlet and Triplet Energies of Bipolar Hosts Based on Indolocarbazole/1, 3, 5‐Triazine Hybrids
Authors: Zhang Dongdong , Duan Lian , Li Yilang , Li Haoyuan , Bin Zhengyang , Zhang Deqiang , Qiao Juan , Dong Guifang , Wang Liduo , Qiu Yong
Published: March 2014

Orange‐emitting phosphorescent organic light‐emitting diodes (PHOLEDs) are drawing more and more attention; however, high‐performance hosts designed for orange PHOLEDs are rare. Here, four indolocarbazole/1, 3, 5‐triazine hybrids are synthesized to optimize the singlet and triplet energies, as well as transporting properties, for ideal orange PHOLEDs. By introducing moieties with different electronegativity, a graded reduction of the singlet and triplet energies is achieved, resulting in minimum injection barrier and minimum energy loss. Besides, the charge transporting abilities are also tuned to be balanced on the basis of the bipolar features of those materials. The optimized orange PHOLED shows a maximum external quantum efficiency (EQE) of 24.5% and a power efficiency of 64 lm W–1, both of which are among the best values for orange PHOLEDs. What is more, the efficiency roll‐off is extremely small, with an EQE of 24.4% at 1000 cd m–2 and 23.8% at 10 000 cd m–2, respectively, which is the lowest efficiency roll‐off for orange PHOLEDs to date, resulting in the highest EQE for orange PHOLEDs when the luminance is above 1000 cd m–2. Besides the balanced charges, the small roll‐off is also attributed to the wide recombination zone resulting from the bipolar features of the hosts.
Influence of polymer on dynamic interfacial tensions of EOR surfactant solutions
Authors: Ma Bao‐dong , Gao Bao‐yu , Zhang Lei , Gong Qing‐tao , Jin Zhi‐qiang , Zhang Lu , Zhao Sui
Published: March 2014

The effects of different types of polymers, partially hydrolyzed polyacrylamide (HPAM) and hydrophobically modified polyacrylamide (HMPAM), on dynamic interfacial tensions (IFTs) of surfactant/model oil systems have been investigated by the spinning drop method in this article. Two anionic surfactants, 1,2‐dihexyl‐4‐propylbenzene sulfonate (366), 1,4‐dibutyl‐2‐nonylbenzene sulfonate (494) and an anionic–nonionic surfactant octyl‐[ω‐alkyloxy‐poly(oxyethylene)]yl‐benzene sulfonates (828) with high purity were selected as model surfactants. The influences of polymer concentration on IFT were expounded. It was found that the addition of polymer mostly results in increasing IFT because the interfacial molecular arrangement is modified owing to the interaction between polymer and surfactants. For HPAM, the polymer chains will enter the surfactant adsorption layer to form mixed‐adsorption layer. Therefore, HPAM shows strong effect on surfactant molecules with large size, such as 366. Conversely, surfactants can interact with the hydrophobic blocks of HMPAM and form mixed micelle‐like associations at interface. As a result, HMPAM shows more impact on IFT of 494 due to small steric hindrance for the formation of interfacial associations. This mechanism has been ensured by 828 molecules with two long alkyl chains. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40562.
The influence of synoptic weather regimes on UK air quality: analysis of satellite column NO2
Authors: Pope R. J. , Savage N. H. , Chipperfield M. P. , Arnold S. R. , Osborn T. J.
Published: March 2014

Groupings of Lamb weather types (LWTs) are used to assess the influence of synoptic meteorology on UK tropospheric column NO2. Composite satellite maps using daily 2005–2011 data show significant NO2 anomalies for each group. Hence, despite large day‐to‐day variability and significant uncertainty in individual retrievals, the satellite data can be used to determine national‐scale column NO2 variations under different meteorological conditions. Under cyclonic conditions, NO2 is reduced, while anticyclonic conditions aid its accumulation, especially during winter, consistent with trapping of surface emissions and slower photochemical processing. This composite dataset can be used to test seasonal simulations of air quality models.
Hydrological scenario reduction for stochastic optimization in hydrothermal power systems
Authors: Aravena Ignacio , Gil Esteban
Published: March 2014

Most of the methods developed for hydrothermal power system planning are based on scenario‐based stochastic programming and therefore represent the stochastic hydro variable (water inflows) as a finite set of hydrological scenarios. As the level of detail in the models grows and the associated optimization problems become more complex, the need to reduce the number of scenarios without distorting the nature of the stochastic variable is arising. In this paper, we propose a scenario reduction method for discrete multivariate distributions based on transforming the moment‐matching technique into a combinatorial optimization problem. The method is applied to hydro inflow data from the Chilean Central Interconnected System and is benchmarked against results for the optimal operation of the Chilean Central Interconnected System determined with the selected subsets and the complete set of historical hydrological scenarios. Simulation results show that the proposed scenario‐reduction method could adequately approximate the probability distribution of the objective function of the operational planning problem. Copyright © 2014 John Wiley & Sons, Ltd.
Local risk‐minimization with longevity bonds
Authors: Henriksen Lars Frederik Brandt , Møller Thomas
Published: March 2014

This paper studies the criterion of local risk‐minimization for life insurance contracts in a financial market, which includes longevity bonds. The longevity bond is a bond specifying payments, which are linked to the current number of survivors in a given portfolio of insured lives. The number of survivors is modeled via a double‐stochastic process, where the mortality intensity is driven by a time‐inhomogeneous Cox–Ingersoll–Ross model. In addition to the longevity bond, the financial market is assumed to consist of a traditional bond and a savings account. We define the price process of the longevity bond by introducing a pricing measure. The paper extends previous work in the literature to the case where the traded assets are not martingales under the measure used for determining the optimal strategies. We compare our results under the real measure with the former results of globally risk‐minimizing strategies, obtained using an equivalent martingale measure. Copyright © 2014 John Wiley & Sons, Ltd.
Hypervalent Iodine‐Mediated Selective Oxidative Functionalization of (Thio)chromones with Alkanes
Authors: Narayan Rishikesh , Antonchick Andrey P.
Published: March 2014

CC bond formation is the most fundamental way for the chain propagation in organic molecules. This achievement through tandem oxidation of two different CH bonds represents the state of the art in organic synthesis. Selective functionalization of the ubiquitous aliphatic CH bonds offers an attractive option for this oxidative cross‐coupling methodology. To develop such a methodology under mild and “metal‐free” conditions remains challenging. Herein, we report hypervalent iodine‐mediated selective oxidative functionalization of aliphatic CH bonds of alkanes with chromones and (thio)chromones. A wide range of alkanes, both cyclic and acyclic, has been found to react selectively and predictably in good yields. The developed methodology is also the first report of a direct oxidative functionalization of the C‐2 position of (thio)chromones with alkanes to access bioactive compounds.
ChemInform Abstract: Stabilization of Carbon‐Supported Palladium Nanoparticles Through the Formation of an Alloy with Gold: Application to the Sonogashira Reaction.
Authors: Rossy Cybille , Majimel Jerome , Fouquet Eric , Delacote Cyril , Boujtita Mohammed , Labrugere Christine , Treguer‐Delapierre Mona , Felpin Francois‐Xavier
Published: March 2014

The recyclable Pd‐alloy nanoparticles are used as catalyst for the Sonogashira‐coupling of several substituted aryl iodides and aryl acetylenes, as well as alkyl acetylenes with good yields.
A genome‐wide association study platform built on iPlant cyber‐infrastructure
Authors: Wang Liya , Ware Doreen , Lushbough Carol , Merchant Nirav , Stein Lincoln
Published: March 2014

We demonstrate a flexible genome‐wide association study platform built upon the iPlant Collaborative Cyber‐infrastructure. The platform supports big data management, sharing, and large‐scale study of both genotype and phenotype data on clusters. End users can add their own analysis tools and create customized analysis workflows through the graphical user interfaces in both iPlant Discovery Environment and BioExtract server. Copyright © 2014 John Wiley & Sons, Ltd.
Cross‐cultural examination of beliefs about the causes of bulimia nervosa among Australian and Japanese females
Authors: Dryer Rachel , Uesaka Yuri , Manalo Emmanuel , Tyson Graham
Published: March 2014

Objective

To identify similarities and differences in beliefs about the causes of Bulimia Nervosa (BN) held by Asian (Japanese) women and Western (Australian) women, and hence, to examine the applicability of belief models of eating disorders (ED) across different cultures.

Method

Four hundred three Japanese and 256 Australian female university students (aged 17–35 years) completed a questionnaire that gauged beliefs about the causes of BN.

Results

Among the Australian women, the four‐component structure of perceived causes (dieting and eating practices, family dynamics, socio‐cultural pressure, and psychological vulnerability) found in Dryer et al. (2012) was replicated. Among the Japanese women, however, a three‐component structure (without the psychological vulnerability component) was obtained. The groups also differed in the causal component they most strongly endorsed, that being socio‐cultural pressure for the Australian women, and dieting and eating practices for the Japanese women.

Discussion

The Japanese participants were found to endorse three out of the four Western‐based causal explanations for BN, but the relative importance they placed on those explanations differed from that of the Australian participants. Further research is needed, particularly to establish whether Japanese women simply fail to see psychological vulnerability as a viable cause of BN, or there are in fact cultural differences in the extent to which such vulnerability causes BN. © 2014 Wiley Periodicals, Inc. (Int J Eat Disord 2015; 48:176–186)
A long‐term field experiment of soil transplantation demonstrating the role of contemporary geographic separation in shaping soil microbial community structure
Authors: Sun Bo , Wang Feng , Jiang Yuji , Li Yun , Dong Zhixin , Li Zhongpei , Zhang Xue‐Xian
Published: March 2014

The spatial patterns of microbial communities are largely determined by the combined effects of historical contingencies and contemporary environmental disturbances, but their relative importance remains poorly understood. Empirical biogeographic data currently available are mostly based on the traditional method of observational survey, which typically involves comparing indigenous microbial communities across spatial scales. Here, we report a long‐term soil transplantation experiment, whereby the same two soils (red Acrisol and purple Cambisol from Yingtan) were placed into two geographic locations of ~1000 km apart (i.e., Yingtan in the mid‐subtropical region and Fengqiu in warm‐temperate region; both located in China). Twenty years after the transplantation, the resulting soil microbial communities were subject to high‐throughput 454 pyrosequencing analysis of 16S and 18S rRNA genes. Additionally, bacteria and archaea involved in nitrogen cycling were estimated using clone library analysis of four genes: archaeal amoA, bacterial amoA, nirK, and nifH. Data of subsequent phylogenetic analysis show that bacteria, fungi, and other microbial eukaryotes, as well as the nitrogen cycling genes, are grouped primarily by the factor of geographic location rather than soil type. Moreover, a shift of microbial communities toward those in local soil (i.e., Chao soil in Fengqiu) has been observed. The results thus suggest that the historical effects persistent in the soil microbial communities can be largely erased by contemporary disturbance within a short period of 20 years, implicating weak effects of historical contingencies on the structure and composition of microbial communities in the soil.
Hierarchical N‐Doped TiO2 Microspheres with Exposed (001) Facets for Enhanced Visible Light Catalysis
Authors: Li Zhongtao , Ren Zhiyu , Qu Yang , Du Shichao , Wu Jun , Kong Lingjun , Tian Guohui , Zhou Wei , Fu Honggang
Published: March 2014

Hierarchical N‐doped TiO2 microspheres with exposed (001) facets [N‐TiO2‐(001)] were synthesized through a simple, fluorine‐free solvothermal reaction with subsequent thermal treatment. The results show that the hierarchical N‐TiO2‐(001) microspheres are made up of numerous TiO2 nanosheets, and that isopropylamine (IPAN) acts as both the nitrogen source and the capping and shape‐controlling agent that generates the high‐energy (001) facets. In addition, IPAN is also effective in increasing the onset temperature of the phase transformation of TiO2 from anatase to rutile. Compared with the commercially available P25 TiO2, the as‐prepared TiO2 microspheres exhibit good photocatalytic activity and high stability under visible‐light irradiation. The high photocatalytic performance is derived from the synergy effect of N‐doping and the separation of photogenerated electrons and holes among different facets, as evidenced by surface photovoltage spectroscopy.
Synthesis of Purine Nucleosides from D‐Glucuronic Acid Derivatives and Evaluation of Their Cholinesterase‐Inhibitory Activities
Authors: Xavier Nuno M. , Schwarz Stefan , Vaz Pedro D. , Csuk René , Rauter Amélia P.
Published: March 2014

Glucuronolactones were used as precursors for N9 and N7 purine nucleosides containing glucuronic acid derivatives in their structures. Acetylated N‐benzylglucofuran‐ and glucopyranuronamides were synthesized in a few steps from glucofuranurono‐6,3‐lactone. They were converted into the corresponding furanosyl and pyranosyl uronamide‐based nucleosides by N‐glycosylation with silylated 2‐acetamido‐6‐chloropurine in the presence of trimethylsilyl triflate. The triacetylated bicyclic lactone was coupled itself with the nucleobase to give bicyclic N9,N7 nucleosides. Tri‐O‐acetylglucopyranurono‐6,1‐lactone was used for the first time as a glycosyl donor for N‐glycosylation, and led to β‐configured N9‐ and N7‐linked purinylglucuronides under reaction conditions similar to those used with the 1‐O‐acetyl‐substituted glycosyl donors. The cholinesterase inhibitory profiles of the synthetic nucleosides bearing glucuronic acid derivatives as glycons were evaluated, and they showed moderate selective acetylcholinesterase inhibitory activities (Ki = 14.78–50.53 μM). The best inhibition was shown by the furanosyl N9‐linked uronamide‐based purine nucleoside.
Biomechanical analyses of prosthetic mesh repair in a hiatal hernia model
Authors: Alizai Patrick Hamid , Schmid Sofie , Otto Jens , Klink Christian Daniel , Roeth Anjali , Nolting Jochen , Neumann Ulf Peter , Klinge Uwe
Published: March 2014

Recurrence rate of hiatal hernia can be reduced with prosthetic mesh repair; however, type and shape of the mesh are still a matter of controversy. The purpose of this study was to investigate the biomechanical properties of four conventional meshes: pure polypropylene mesh (PP‐P), polypropylene/poliglecaprone mesh (PP‐U), polyvinylidenefluoride/polypropylene mesh (PVDF‐I), and pure polyvinylidenefluoride mesh (PVDF‐S). Meshes were tested either in warp direction (parallel to production direction) or perpendicular to the warp direction. A Zwick testing machine was used to measure elasticity and effective porosity of the textile probes. Stretching of the meshes in warp direction required forces that were up to 85‐fold higher than the same elongation in perpendicular direction. Stretch stress led to loss of effective porosity in most meshes, except for PVDF‐S. Biomechanical impact of the mesh was additionally evaluated in a hiatal hernia model. The different meshes were used either as rectangular patches or as circular meshes. Circular meshes led to a significant reinforcement of the hiatus, largely unaffected by the orientation of the warp fibers. In contrast, rectangular meshes provided a significant reinforcement only when warp fibers ran perpendicular to the crura. Anisotropic elasticity of prosthetic meshes should therefore be considered in hiatal closure with rectangular patches. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 1485–1495, 2014.
Failure evaluation of steam‐side oxide scales in superheater tubes during unsteady thermal processes: A probabilistic method
Authors: Huang J.‐L. , Zhou K.‐Y. , Xu J.‐Q. , Xu X.‐H. , Xie J.‐W.
Published: March 2014

Issues resulting from failure of steam‐side oxide scales in boiler superheater or reheater tubes seriously influence the safety of coal‐fired power plants. In this work, an analysis model for the failure of steam‐side oxide scales during unsteady thermal processes is established. This model employs the advanced oxide scale failure diagram as the failure criterion, and also takes into account the influence of temperature on the coefficients of thermal expansion of both metal substrate and oxide scale. Since the stochastic nature of related geometrical, mechanical, and thermophysical parameters may hinder the usual deterministic investigation from obtaining a reliable evaluation, probabilistic failure evaluation which is not based on bivalent logic is thus performed. Focusing on the unsteady thermal processes induced by the variation of steam temperature, effects of oxide scale thickness as well as different steam temperature variation processes on the failure probability of steam‐side oxide scales are analyzed. It is found that the failure probability of thicker steam‐side oxide scales is higher, while through reasonably selecting steam temperature variation mode and appropriately lengthening variation duration, lower failure probability can be achieved. Feasible measures are presented with the aspiration to solve the steam‐side oxide scale failure issues.
Some properties of a class of symmetric functions and its applications
Authors: Sun Mingbao , Chen Nanbo , Li Songhua
Published: March 2014

For , the symmetric functions are defined by

urn:x-wiley:dummy:mana201300073:equation:mana201300073-math-0003where , and are non‐negative integers. In this paper, the Schur convexity, geometric Schur convexity and harmonic Schur convexity of are investigated. As applications, Schur convexity for the other symmetric functions is obtained by a bijective transformation of independent variable for a Schur convex function, some analytic and geometric inequalities are established by using the theory of majorization, in particular, we derive from our results a generalization of Sharpiro's inequality, and give a new generalization of Safta's conjecture in the n‐dimensional space and others.
Identification of Hsf1 as a novel androgen receptor‐regulated gene in mouse Sertoli cells
Authors: Yang Lihua , Wang Yadong , Zhang Qiang , Lai Yongqing , Li Cailing , Zhang Qiaoxia , Huang Weiren , Duan Yonggang , Jiang Zhimao , Li Xianxin , Cai Zhiming , Mou Lisha , Gui Yaoting
Published: March 2014

Androgen signaling plays a crucial role in spermatogenesis, yet few downstream targets for this signaling pathway have been identified. In the current study, we found that the expression of heat‐shock transcription factor 1 (Hsf1) was increased in the testes of Sertoli cell‐selective androgen receptor knockout (S‐AR−/y) mice compared with wild‐type mice by quantitative real‐time PCR, and the expression of HSF1 in the S‐AR−/y Sertoli cells was significantly increased, based on immunofluorescence analysis. In vitro cell‐culture studies showed that testosterone repressed the expression of Hsf1 in TM4 cells, a mouse Sertoli cell line. Moreover, a luciferase assay, electrophoretic mobility shift assay, and chromatin immunoprecipitation assay showed that testosterone repressed Hsf1 expression by facilitating the binding of androgen receptor to the Hsf1 promoter. Our experiments also demonstrated that testosterone‐mediated inhibition of Hsf1 transcription down‐regulated the expression of heat‐shock proteins HSP105 and HSP60. Taken together, these results reveal that Hsf1 is a novel target of androgen receptor in mouse Sertoli cells, and testosterone and its receptor regulate the process of spermatogenesis partially by inhibiting Hsf1 expression. Mol. Reprod. Dev. 81: 514–523, 2014. © 2014 Wiley Periodicals, Inc.
Conjugated polymers for the fluorescent detection of nitroaromatics: Influence of side‐chain sterics and π‐system electronics
Authors: Duniho Tyler L. , Laughlin Brynna J. , Buelt Ashley A. , Baker William F. , Conrad Catherine A. , Smith Rhett C.
Published: March 2014

A series of eight poly(p‐phenylene vinylene) (PPV) and poly(p‐phenylene ethynylene) (PPE) (P1–P8) derivatives were tested for their ability to detect the nitroaromatic explosive 2,4,6‐trinitrotoluene (TNT) and its model compound 2,6‐dinitrotoluene (DNT). The polymers P1–P8 represent five structural classes that have not been examined for nitroaromatic sensing. These new motifs include PPE derivatives with a main‐chain m‐terphenyl unit (P1) or oxacyclophane canopy‐like structure (P2) and PPV derivatives with 2,6‐mesitylenephenylene repeats (P3 and P4), 9,9‐dialkyl‐1,4‐fluorenylene repeats (P5 and P6), or m‐phenylene units that periodically disrupt π‐conjugation along the backbone of the polymer (P7 and P8). The time‐dependent photoluminescent response of films to TNT and DNT and the solution‐phase Stern‐Volmer quenching constants for both TNT and DNT were determined. The results are rationalized in terms of side‐chain sterics and π‐system electronics and are discussed relative to known conjugated polymers. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1487–1492
Resistive switching characteristics of indium‐tin‐oxide thin film devices
Authors: Khiat Ali , Salaoru Iulia , Prodromakis Themistoklis
Published: March 2014

We demonstrate that indium tin oxide (ITO), when used as an active core material in metal–insulator–metal type devices, facilitates resistive switching. We fabricated devices both on silicon as well as quartz wafers, to demonstrate transparent devices. Furthermore, we investigated the influence of active core thickness on the devices' characteristics, showing that their switching threshold scales with the ITO thickness. Unipolar switching was observed for devices comprising thick ITO films while bipolar switching occurred for both thin and thick ITO films at the absence of high voltage forming steps. Our study demonstrates that ITO holds good potential for resistive memory applications.
The influence of external separate heating on the synchronization of Josephson junctions
Authors: Grib Alexander , Seidel Paul
Published: March 2014

Recent experiments on synchronized radiation from intrinsic Josephson junctions in high‐temperature superconductors showed that the difference of temperatures of the junctions can influence synchronization. We investigated numerically the mechainsm of this influence on the example of two overdamped Josephson junctions loaded by a shunt consisting of the resistance and the inductance. We showed that strong synchronization of radiation was obtained by means of external separate heating/cooling of junctions. Due to the change of critical currents in the process of heating or cooling, the current–voltage (I–V) characteristics of the junctions cross each other and junctions are synchronized by the ac current in the load in the vicinity of this crossing. The maximal tolerant spread of critical currents for this mechanism of synchronization is 15–20% that is twice larger than the maximal tolerant spread for this system without the separate heating.

I–V characteristics of two separately heated junctions. Phase locking in this system is impossible without heating for such large spreads of critical currents.
Elimination of isobaric interference and signal‐to‐noise ratio enhancement using on‐line mobile phase filtration in liquid chromatography/tandem mass spectrometry
Authors: Lahaie Mathieu , Youhnovski Nikolay , Furtado Milton , Garofolo Fabio
Published: March 2014

RATIONALE

Liquid chromatography/tandem mass spectrometry (LC/MS/MS) instruments are selective and sensitive but can still be affected by isobaric interference or chemical noise arising from multiple sources such as the mobile phase. In this study, a high‐performance liquid chromatography (HPLC) on‐line mobile phase filtration setup is described and used to remove interference to allow better detection of the analyte of interest.

METHODS

For instance, a filtration device containing a chemical sorbent is installed at the HPLC outlet of the aqueous solvent pump A or the organic solvent pump B. This manuscript reports different case scenarios under reversed‐phase and HILIC separations either in positive (ESI(+)) or negative electrospray ionization (ESI(–)) mode using selected reaction monitoring (SRM) scans as well as additional Q1 MS scans.

RESULTS

The filtration of the aqueous effluent of the mobile phase using a porous graphitic carbon filter eliminated the isobaric interferences and improved the detectability of gestodene and perindopril‐D4. Also, a strong cation‐exchange guard column installed at the acetonitrile outlet pump was found helpful on reducing the baseline intensity and improving significantly the signal‐to‐noise ratio (S/N) of methenamine. Moreover, the on‐line mobile phase filtration was efficient at removing chemical background ions in full scan mode.

CONCLUSIONS

This strategy demonstrated its usefulness by removing co‐eluting isobaric interference, and reducing chemical background ions from the mobile phase, while drastically improving S/N. Copyright © 2014 John Wiley & Sons, Ltd.
Einfluss von Querkraftanschlüssen auf das Biegedrillknicken von Einfeldträgern – Teil 2: Aufbereitung für die Praxis
Authors: Mensinger Martin , Möller Heidrun
Published: March 2014

Querkraftanschlüsse stellen eine häufig verwendete oberkantenbündige Verbindungsmöglichkeit eines Nebenträgers an einen Hauptträger dar. Hierbei zeichnen sich insbesondere lange Fahnenblechanschlüsse durch ihre Vorteile in der Montage aus. Ausgeklinkte Träger mit Doppelwinkel‐ oder Fahnenblechanschlüssen müssen aufgrund der Ausklinkung des Nebenträgers umständlich zwischen die Hauptträger eingeschwenkt werden, stellen aber nichts desto trotz eine gerne verwendete Anschlussform mit großer Tradition dar. Allen Varianten gemein ist die Tatsache, dass sie kein Gabellager bilden, sondern ein torsionsweiches Auflager. Damit sind die üblichen Berechnungsmöglichkeiten zur Ermittlung des idealen Biegedrillknickmomentes Mcr nicht anwendbar. Um für Träger mit diesen Anschlüssen Mcr ermitteln zu können und damit die Grundlage für einen normkonformen Nachweis zu legen, bedurfte es einiger eingehender Untersuchungen. Im Rahmen des AiF‐Forschungsvorhabens 16872 N wurden diese Untersuchungen am Lehrstuhl für Metallbau der Technischen Universität München durchgeführt. Im folgenden Beitrag wird auf die Erkenntnisse der Parameterstudie, das Ersatzmodell zur Ermittlung von Mcr sowie auf die weiteren Hilfsmittel, aufbereitet für die Praxis, eingegangen (s. auch Teil 1 [9]).

Influence of hinged connections on the lateral‐torsional buckling of single‐span beams – Part 2: Practical application. Hinged connections are an often used type of connection between secondary and primary beam with flushed upper flanges. A very economic type of connection in terms of manufacturing and erection are long fin‐plates. Unfortunately they are no fork bearing, therefore the usual formula for the elastic critical moment Mcr for beams cannot be used. To design a beam according to DIN EN 1993‐1‐1 it is necessary to know the actual stiffness of such connections to be able to consider it in the calculation of Mcr. This is also the case for other typical hinged connections like notched beams with either fin‐plate or double angle connection. This problem of otherwise very economic connections is the reason for taking a closer look at their influence on the lateral‐torsional buckling in the research project AiF‐No. 16872 N at the Lehrstuhl für Metallbau (chair of metal structures) der Technischen Universität München. The following second part of the paper deals with the results of the parametric study, the substitute model to calculate Mcr and the additional aids for practical use (for part 1 of the paper see [9]).
Apolipoprotein E receptor pathways in Alzheimer disease
Authors: Schmidt Vanessa , Carlo Anne‐Sophie , Willnow Thomas E.
Published: March 2014

Alzheimer disease (AD) is the most common neurodegenerative disease affecting millions of patients worldwide. According to the amyloid cascade hypothesis, the formation of neurotoxic oligomers composed of amyloid‐β (Aβ) peptides is the main mechanism that causes synaptic dysfunction and, eventually, neuronal cell death in this condition. Intriguingly, apolipoprotein E (apoE), the most important genetic risk factor for sporadic AD, emerges as a key factor that contributes to many aspects of the amyloid cascade including the clearance of Aβ from brain interstitial fluid and the ability of this peptide to form neurotoxic oligomers. Central to the activity of apoE in the healthy and in the diseased brain are apoE receptors that interact with this protein to mediate its multiple cellular and systemic effects. This review describes the molecular interactions that link apoE and its cellular receptors with neuronal viability and function, and how defects in these pathways in the brain promote neurodegeneration.

This article is categorized under:

Models of Systems Properties and Processes > Cellular Models

Biological Mechanisms > Metabolism

Physiology > Mammalian Physiology in Health and Disease
Integrating Pricing and Inventory Control: Is it Worth the Effort?
Authors: Gimpl-Heersink Lisa , Rudloff Christian , Fleischmann Moritz , Taudes Alfred
Published: March 2014

In this paper we first show that the gains achievable by integrating pricing and inventory control are usually small for classical demand functions. We then introduce reference price models and demonstrate that for this class of demand functions the benefits of integration with inventory control are substantially increased due to the price dynamics. We also provide some analytical results for this more complex model. We thus conclude that integrated pricing/inventory models could repeat the success of revenue management in practice if reference price effects are included in the demand model and the properties of this new model are better understood.
Do Taxes Matter in the CAPM?
Authors: Kruschwitz Lutz , Löffler Andreas
Published: March 2014

The traditional literature on the CAPM assumes that investor’s tax payments simply vanish from the model. This assumption is not at all consistent with the actual behavior of the Treasury. The theory of general equilibrium states that an interest rate rf = 0 will not affect prices if taxes are introduced. We show that this result can be extended to the CAPM if the tax payments are redistributed among investors.
Tariff-Specific Preferences and Their Influence on Price Sensitivity
Authors: Wolk Agnieszka , Skiera Bernd
Published: March 2014

For many services, consumers can choose among a range of optional tariffs that differ in their access and usage prices. Recent studies indicate that tariff-specific preferences may lead consumers to choose a tariff that does not minimize their expected billing rate. This study analyzes how tariff-specific preferences influence the responsiveness of consumers’ usage and tariff choice to changes in price. We show that consumer heterogeneity in tariff-specific preferences leads to heterogeneity in their sensitivity to price changes. Specifically, consumers with tariff-specific preferences are less sensitive to price increases of their preferred tariff than other consumers. Our results provide an additional reason why firms should offer multiple tariffs rather than a uniform nonlinear pricing plan to extract maximum consumer surplus.
Setting Inventory Levels of CONWIP Flow Lines via Linear Programming
Authors: Helber Stefan , Schimmelpfeng Katja , Stolletz Raik
Published: March 2014

This paper treats the problem of setting the inventory level and optimizing the buffer allocation of closed-loop flow lines operating under the constant-work-in-process (CONWIP) protocol. We solve a very large but simple linear program that models an entire simulation run of a closed-loop flow line in discrete time to determine a production rate estimate of the system. This approach introduced in Helber, Schimmelpfeng, Stolletz, and Lagershausen (2011) for open flow lines with limited buffer capacities is extended to closed-loop CONWIP flow lines. Via this method, both the CONWIP level and the buffer allocation can be optimized simultaneously. The first part of a numerical study deals with the accuracy of the method. In the second part, we focus on the relationship between the CONWIP inventory level and the short-term profit. The accuracy of the method turns out to be best for such configurations that maximize production rate and/or short-term profit.
Exact Solutions to the Symmetric and Asymmetric Vehicle Routing Problem with Simultaneous Delivery and Pick-Up
Authors: Rieck Julia , Zimmermann Jürgen
Published: March 2014

In reverse logistics networks, products (e.g., bottles or containers) have to be transported from a depot to customer locations and, after use, from customer locations back to the depot. In order to operate economically beneficial, companies prefer a simultaneous delivery and pick-up service. The resulting Vehicle Routing Problem with Simultaneous Delivery and Pick-up (VRPSDP) is an operational problem, which has to be solved daily by many companies. We present two mixed-integer linear model formulations for the VRPSDP, namely a vehicle-flow and a commodity-flow model. In order to strengthen the models, domain-reducing preprocessing techniques, and effective cutting planes are outlined. Symmetric benchmark instances known from the literature as well as new asymmetric instances derived from real-world problems are solved to optimality using CPLEX 12.1.
Authoritarian Origins of Democratic Party Systems in Africa
Authors: Riedl Rachel Beatty
Published: March 2014

Why have seemingly similar African countries developed very different forms of democratic party systems? Despite virtually ubiquitous conditions that are assumed to be challenging to democracy - low levels of economic development, high ethnic heterogeneity, and weak state capacity - nearly two dozen African countries have maintained democratic competition since the early 1990s. Yet the forms of party system competition vary greatly: from highly stable, nationally organized, well-institutionalized party systems to incredibly volatile, particularistic parties in systems with low institutionalization. To explain their divergent development, Rachel Beatty Riedl points to earlier authoritarian strategies to consolidate support and maintain power. The initial stages of democratic opening provide an opportunity for authoritarian incumbents to attempt to shape the rules of the new multiparty system in their own interests, but their power to do so depends on the extent of local support built up over time.
Constructing Cause in International Relations
Authors: Lebow Richard Ned
Published: March 2014

Cause is a problematic concept in social science, as in all fields of knowledge. We organise information in terms of cause and effect to impose order on the world, but this can impede a more sophisticated understanding. In his latest book, Richard Ned Lebow reviews understandings of cause in physics and philosophy and concludes that no formulation is logically defensible and universal in its coverage. This is because cause is not a feature of the world but a cognitive shorthand we use to make sense of it. In practice, causal inference is always rhetorical and must accordingly be judged on grounds of practicality. Lebow offers a new approach - 'inefficient causation' - that is constructivist in its emphasis on the reasons people have for acting as they do, but turns to other approaches to understand the aggregation of their behaviour. This novel approach builds on general understandings and idiosyncratic features of context.