bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of androgens on periodontal repair in female rats
Authors: Steffens João Paulo , Santana Luis Carlos Leal , Pitombo Jonleno Coutinho Paiva , Ribeiro Daniel Olivio , Albaricci Maria Carolina Costa , Warnavin Stephanie von Stein Cubas , Kantarci Alpdogan , Spolidorio Luis Carlos
Published: February 2018

Background

Testosterone replacement enhances cognitive function and musculoskeletal health in postmenopausal women. However, the biological role of testosterone on inflammation and bone metabolism in females is not well understood. Our objective was to measure the impact of androgens and their receptors on periodontal tissues during periodontal repair in female rats.

Methods

Seventy female Holtzman rats were divided into seven groups (n = 10/group): negative control; repair control; androgen receptor antagonist (flutamide, 50 mg/kg, every other day); estrogen receptor antagonist (fulvestrant, 1.5 mg/kg/day); testosterone supplementation (durateston, 250 mg/kg, weekly); aromatase inhibitor (anastrozole, 0.2 mg /kg/day); testosterone plus anastrozole. Cotton ligatures were kept for 13 days, when pharmacological treatment was initiated. On day 14, the ligatures were removed. The rats were euthanized on the 17th or the 28th day (n = 5/group/period) for the evaluation of markers related to inflammation and bone. The tissue and serum samples were evaluated using a multiplexed immunoassay for the inflammatory targets. Radiographic and histologic analyses were performed to assess changes in tissues.

Results

Blockage of androgen receptors had little effect on inflammatory cell count, although it tended to increase interleukin (IL)‐4, vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF) as well as decrease IL‐1β, tumor necrosis factor (TNF)‐α, and IL‐6. Flutamide also significantly impaired bone repair (P < 0.05) and had greater osteoclast count, although this last difference was not statistically significant. Testosterone supplementation significantly increased the inflammatory cell count, decreased the levels of IL‐4, IL‐10, IL‐1β, IL‐6, and TNF‐α; and increased VEGF and EGF.

Conclusion

The blockage of androgen receptors significantly impair bone repair in females through mechanisms that are different from those related to estrogen receptors.
Global perspectives on the impact of drastic environmental changes in hunter‐gatherer technologies
Authors: Bicho Nuno , Cascalheira João
Published: February 2018

Researchers have long debated the impact of climate change on human culture and particularly in hunter‐gatherer societies. Climate drifts, particularly abrupt ones, have been continuingly seen as major prompts for rapid technological and cultural innovation. Recent advances in paleoclimatic reconstructions and ongoing developments in the quality and chronological resolution of archeological data have allowed a better understanding of the extent to which patterns of specific environmental changes triggered modifications in the technological systems of hunter‐gatherers. This volume brings together contributions addressing strategic changes in the organization of hunter‐gatherer technologies as a response to drastic environmental shifts. It includes topics such as lithic, organic tools and ceramic production, pyrotechnology, hunting strategies, pigment processing, use of plants and adornments, starting with Middle Stone Age and ending with Mesolithic and coming from a diversity of geographical contexts. This introduction to the volume provides a general view on the continuing debate over cause and effect in the interplay between humans and climate with the aim to provide a better understanding of the role and magnitude of environmental determinism in the archeology of hunter‐gatherers.
Volatile composition of Carignan noir wines from ungrafted and grafted onto País (Vitis vinifera L.) grapevines from ten wine‐growing sites in Maule Valley, Chile
Authors: Gutiérrez‐Gamboa Gastón , Garde‐Cerdán Teresa , Carrasco‐Quiroz Marioli , Pérez‐Álvarez Eva Pilar , Martínez‐Gil Ana María , Del Alamo‐Sanza María , Moreno‐Simunovic Yerko
Published: February 2018

BACKGROUND

Carignan noir is one of the minor and ancient varieties from the Chilean wine scenario that has had a resurgence as a result of to its rediscovered oenological potential when cultivated under the conditions of the interior dryland area. Under these growing conditions Carignan noir wines stand out as fruit driven and fresh compared to those originating from other growing areas. On the other hand, it is well known that wine aroma composition depends mainly on variety, viticultural management and winemaking. Thus, the present study aimed to investigate the volatile composition of wines from Carignan noir grapes originating from ungrafted and grafted onto País grapevines, in ten sites of the Maule Valley (Chile) during two consecutive vintages.

RESULTS

Higher alcohols were the most abundant volatile compounds, whereas ethyl esters and ß‐damascenone were the most odoriferous compounds according to their odorant activity value. The dominant factor in Carignan noir wine volatile composition was season, whereas rootstock did not have a significant effect in differentiating the wines. In terms of climate, cold nights during the month prior to harvest correlated with higher linalool, α‐terpineol and trans‐3‐hexen‐1‐ol content. The biologically effective degree‐days index was inversely correlated with isoamyl acetate and 2‐phenylethyl acetate content. Huglin's heliothermal and the average mean temperature of the warmest month indices were inversely correlated with ethyl vanillate, ethyl hexanoate and ethyl octanoate content.

CONCLUSION

Site climate conditions were related to the accumulation of certain wine volatile compounds. This information may be useful for devising new Carignan noir vineyard management strategies when aiming to improve wine quality or adjust site selection approaches to maximize grape/wine volatile composition according to wine style. © 2018 Society of Chemical Industry
Biochar influences soil carbon pools and facilitates interactions with soil: A field investigation
Authors: El‐Naggar Ali , Awad Yasser M. , Tang Xiang‐Yu , Liu Chen , Niazi Nabeel Khan , Jien Shih‐Hao , Tsang Daniel C.W. , Song Hocheol , Ok Yong Sik , Lee Sang Soo
Published: February 2018

Biochar promotes the storage of organic carbon (OC) in soils. OC is unevenly distributed in soils among different particle‐size fractions showing different structures, functions, and stability. The objective of this study was to investigate the biochar–soil interactions and the redistribution of soil C in different soil fractions based on a 2‐year field experiment. Fractionation was done by particle sizes including coarse sand (250–2,000 μm), fine sand (53–250 μm), and silt/clay (<53 μm). Integrated spectroscopic techniques were employed to examine physical characteristics of biochar–soil interactions in different soil fractions. Application of biochar increased OC by 37%, 42%, and 76% in soil particle‐size fractions of 53–250, <53, and 250–2,000 μm, respectively. This was supported by X‐ray fluorescence spectroscopy analysis, which showed an increase of C contents by 5–56% with biochar addition. The highest increment in OC was found in coarse sand fraction, and redistribution of OC was detected depending on various soil particle sizes. Results of scanning electron microscopy combined with electron dispersive X‐ray spectroscopy analysis showed the interactions between soil and biochar, which could be attributed to oxidized functional groups (OCO, CO, and CO) captured by the X‐ray photoelectron spectroscopy. The long‐term aged biochar could be beneficial to enhance soil quality by promoting OC storage and facilitating positive biochar–soil interactions.
Rebuilding soil carbon in degraded steppe soils of Eastern Europe: The importance of windbreaks and improved cropland management
Authors: Wiesmeier Martin , Lungu Marina , Cerbari Valerian , Boincean Boris , Hübner Rico , Kögel‐Knabner Ingrid
Published: February 2018

Long‐term cultivation of steppe soils in a nonsustainable way caused severe soil degradation and reduced agricultural productivity in Eastern Europe, one of the world's most important areas for cereal production. In order to combat soil erosion and maintain yields, a widespread system of tree windbreaks was introduced in the 1950s, accompanied by improved agricultural practices in recent years. However, information on the effectiveness of such measures to rebuild soil organic carbon (SOC) is scarce. The objective of this study was to estimate the OC storage potential of the fine mineral fraction of degraded arable steppe soils in Moldova and to quantify SOC sequestration rates under (a) windbreaks, (b) cropland with improved crop rotation/manure application, and (c) cropland with cover cropping. Natural grassland relicts served as a reference to estimate the SOC saturation potential. Our results revealed a low SOC saturation of 50% under conventional agricultural use due to high SOC losses, indicating a high potential for SOC sequestration. Relatively high SOC sequestration rates were determined for topsoils (0–30 cm) under windbreaks (0.9 t ha−1 yr−1), improved crop rotation/manure application (1.3 t ha−1 yr−1), and cover cropping (1.9 t ha−1 yr−1). In this regard, sequestration rates derived from OC changes of the fine fraction may be more reliable than total SOC‐based rates, particularly for windbreaks with high proportions of labile SOC. We conclude that implementation of improved agricultural management together with the maintenance of windbreaks is a promising strategy to rebuild SOC, reduce widespread soil erosion and compaction, and secure Moldova's agricultural productivity.
Methylotrophic methanogenesis fuels cryptic methane cycling in marine surface sediment
Authors: Xiao Ke‐Qing , Beulig Felix , Røy Hans , Jørgensen Bo Barker , Risgaard‐Petersen Nils
Published: February 2018

Methylotrophic methanogenesis is often proposed to be responsible for methane production in sulfate‐rich environments, yet the magnitude of this process remains elusive. In this study, we incubated sediment from Aarhus Bay (Denmark) with 13C labeled CH4 to measure total methane turnover by isotope dilution, and with 14C‐radiotracers to measure specifically the gross hydrogenotrophic and acetoclastic methane production. Highest CH4 production rates (> 200 pmol cm−3 d−1) were found in the top 0–2 cm. Most of this production was via methylotrophic pathways. Methanogenesis via the hydrogenotrophic pathway accounted for less than 20 pmol cm−3 d−1 throughout the surface sediment (0–10 cm), and there was no apparent contribution from acetoclastic methanogenesis. To further assess potentials for methanogenesis from hydrogen, acetate, or trimethylamine (TMA), sediment slurry incuabtions with excess substrate addition were performed. A high and accelarating CH4 production was only detected in incubations amended with TMA. Our results show that methylotrophic methanogenesis dominated the CH4 production in these sulfate‐rich marine surface sediments.
Pseudo‐Riemannian ‐manifolds with dimension at most 21
Authors: Quiroga‐Barranco Raul
Published: February 2018

Let G2(2) be the non‐compact connected simple Lie group of type G2 over , and let M be a connected analytic complete pseudo‐Riemannian manifold that admits an isometric G2(2)‐action with a dense orbit. For the case , we provide a full description of the manifold M, its geometry and its G2(2)‐action. The latter are always given in terms of a Lie group geometry related to G2(2), and in one case M is essentially the quotient of SO0(3, 4) by a lattice.
Exploring creative marketing thought: Divergent ideation processes and outcomes
Authors: Titus Philip A.
Published: February 2018

Most marketing professionals deem creativity vital to successful marketing performance. However, while previous research has advanced an understanding of creative organizations, much less is known about the cognitive processes that direct the creative thinking of marketing professionals. This article presents a theoretical framework, the Divergent Marketing Thought Model (DMTM), that explores the ideation modes, processes, and outcomes involved in the generation of divergent marketing thought. The proposed model, which is based on a synthesis of research from psychology, marketing, and creativity, offers insight into specific divergent ideation processes that mediate the generation of creative marketing thought. Informed by the DMTM, several formal research propositions are advanced.
Characterization of Swedish Campylobacter coli clade 2 and clade 3 water isolates
Authors: Nilsson Anna , Skarp Astrid , Johansson Cecilia , Kaden René , Engstrand Lars , Rautelin Hilpi
Published: February 2018

Campylobacter jejuni and Campylobacter coli are important bacterial enteropathogens. Poultry is the best‐known reservoir for Campylobacter infection but natural bodies of water have also been shown to be important pathways for transmission. Campylobacter can survive in cold water but most of the studies have focused on C. jejuni only. In this paper, we take a closer look at the biology and water survival strategies of C. coli. Eight C. coli isolates cultivated from raw (incoming) surface water at water plants in Sweden were characterized using whole‐genome sequencing and phenotypical assays. Phylogenetic analysis assigned the Swedish water isolates to clades 2 and 3, known to include C. coli of environmental origin. In addition, 53 earlier published sequences of C. coli clade 2 and 3 from environmental waters were included for in silico analyses. Generally, clade 2 isolates had larger genomes, which included a functional tricarballylate utilization locus, while clade 3 isolates contained different genes involved in oxidative stress as well as putative virulence factors. The Swedish water isolates of clade 2 formed large, blurry bacterial colonies on agar, whereas clade 3 colonies were smaller. All Swedish isolates were motile, but clade 3 isolates formed larger motility zones on soft agar, and none of these isolates produced biofilm. Although water survival varied between the analyzed isolates, there were hardly any clade‐specific significant differences. Our results highlight the diversity of C. coli in general, and show differences in metabolic capabilities and ways to handle oxidative stress between clade 2 and 3 water isolates.
Pathogenesis of cranial neuropathies in Moebius syndrome: Electrodiagnostic orofacial studies
Authors: Renault Francis , Flores‐Guevara Roberto , Sergent Bernard , Baudon Jean Jacques , Aouizerate Jessie , Vazquez Marie‐Paule , Gitiaux Cyril
Published: February 2018

Introduction: We designed a retrospective study of 59 patients with congenital sporadic nonprogressive bilateral facial and abducens palsies. Methods: Examinations included needle electromyography (EMG) of facial and oral muscles, facial nerve motor latency and conduction velocity (FNCV), and blink responses (BR). Results: Neurogenic EMG changes were found in 1 or more muscles in 55 of 59 patients, with no abnormal spontaneous activity. EMG changes were homogeneously neurogenic in 17 patients, homogeneously myopathic in 1 patient, and heterogeneous in 41 of 59 patients. Motor latency was increased according to recordings from 52 of 137 facial muscles. An increase of motor latency was not associated with neurogenic EMG (Fischer's test: right, P = 1; left, P = 0.76). FNCV was slowed in 19 of 36 patients. BR was absent bilaterally in 35 of 58 patients; when present, R1 and R2 latencies were normal. Discussion: Our results support the hypothesis of an early developmental defect localized in motor cranial nerves with spared V–VII internuclear pathways. Muscle Nerve 58: 79–83, 2018
Thymus imaging in myasthenia gravis: The relevance in clinical practice
Authors: Klimiec Elzbieta , Quirke Mary , Leite Maria Isabel , Hilton‐Jones David
Published: February 2018

Introduction: The ability to distinguish between normal thymus, thymic hyperplasia, and thymoma should aid clinical management and decision making in patients with myasthenia gravis (MG). We sought to determine the accuracy of routine imaging in predicting thymic pathology. Methods: We retrospectively analyzed records of patients with MG from the Oxford Myasthenia Centre registry who had undergone thymectomy. Each patient received 1 radiological diagnosis and 1 histological diagnosis. Results: We included 106 patients. Radiological and histological diagnoses agreed in 73 (68.9%) patients. Sensitivity and specificity, respectively, were calculated for each radiological diagnosis as follows: thymoma 90% and 95.5%, hyperplasia 17.6% and 98.6%, and normal 96.9% and 60.8%. Discussion: Routine chest computed tomography and MRI can effectively identify thymoma. However, they are not reliable tools to differentiate between thymic hyperplasia and normal thymus in patients with MG. Muscle Nerve 58: 153–156, 2018
Monitoring of macrophage recruitment enhanced by Toll‐like receptor 4 activation with MR imaging in nerve injury
Authors: Chen Mei‐Wei , Zhang Xiang , Lu Lie‐Jing , Zhang Fang , Duan Xiao‐Hui , Zheng Chu‐Shan , Chen Yue‐Yao , Shen Jun
Published: February 2018

Introduction: Macrophage recruitment is critical for nerve regeneration after an injury. The aim of this study was to investigate whether ultrasmall superparamagnetic iron oxide (USPIO) nanoparticle‐based MRI could be used to monitor the enhanced macrophage recruitment by Toll‐like receptor 4 (TLR4) activation in nerve injury. Methods: Rats received intraperitoneal injections of either lipopolysaccharide (LPS) or phosphate buffered saline (PBS) or no injection (controls) after a sciatic nerve crush injury. After intravenous injection of the USPIOs (LPS and PBS groups) or PBS (control group), MRI was performed and correlated with histological findings. Results: LPS group showed more remarkable hypointense signals on T2*‐weighted imaging and lower T2 values in the crushed nerves than PBS group. The hypointense signal areas were associated with an enhanced recruitment of iron‐loaded macrophages to the injured nerves. Discussion: USPIO‐enhanced MRI can be used to monitor the enhanced macrophage recruitment by means of TLR4 signal pathway activation in nerve injury. Muscle Nerve 58: 123–132, 2018
Towards a Fully Integrated Lab‐On‐A‐Chip
Authors: Nestler Joerg , Peter Harald , Bier Frank
Published: February 2018

The identification of pathogens in body fluids is important for proper treatment of infections with antibiotics. Besides the pure identification of the pathogen's species, however, its antibiotic profile can be crucial with regard to their resistance to certain drugs. By the use of DNA‐based microarrays, multiple of such parameters can be measured at the same time, e.g., by fluorescence imaging. Before the optical detection, however, sample preparation and labeling steps have to be performed which require the controlled transport of liquid reagents and the sample. To perform these steps at the point of care by a portable instrument, a fully‐integrated cartridge technology is presented which can perform all the required pumping and heating steps in a chip‐card‐like format, followed by fluorescence readout of the microarray.
Microdisplays for Smart Eyewear
Authors: Richter Bernd , Wartenberg Philipp , Vogel Uwe
Published: February 2018

Human‐machine interfaces determine how machines serve humanity and in what form information is provided. This can take the form of the label on a simple light switch. However, it can also be a highly complex control console with countless monitors and computers in an industrial facility.
Optical Metrology of Freeforms and Complex Lenses
Authors: Berger Gernot , Wendel Marc
Published: February 2018

Optical surfaces are becoming more and more complex and custom designs increasingly involve freeform surfaces and discontinuous geometries. This article discusses requirements and limitations of optical form measurements as part of the manufacturing process of such extreme optics.
Student experiences with traffic‐light labels at college cafeterias: a mixed methods study
Authors: Seward M. W. , Block J. P. , Chatterjee A.
Published: February 2018

Objective

To assess student perceptions of traffic‐light labels (TLLs) in college cafeterias.

Design

Cross‐sectional, mixed‐methods study.

Setting

One northeastern US college.

Participants

A total of 1,294 survey respondents; 57 focus group participants.

Interventions

Seven‐week traffic‐light labelling (green = ‘nutrient‐rich’, yellow = ‘less nutrient‐rich’, red = ‘more nutrient‐rich choice in green or yellow’) intervention at two college cafeterias.

Main Outcome Measure(s)

Perceptions of TLLs and food labelling; disordered eating behaviours.

Analysis

Performed χ2 analyses to test for differences between pre‐intervention and postintervention responses, and between postintervention subgroups stratified by site, gender, weight status and varsity athlete status. Qualitative analysis based on the immersion‐crystallization method.

Results

In postintervention surveys, 60% found TLLs helpful, and 57% used them a few times a week. When asked whether TLLs increased risk of developing eating disorders, 16% of participants said they did and 47% said TLLs might exacerbate existing eating disorders. In focus groups, some students thought the red ‘colour seemed jarring’, but the vast majority agreed ‘the more nutrition information available, the better’.

Conclusions and Implications

Students generally supported TLLs, but future college‐based interventions should address eating disorder concerns. Labels that incorporate nutrition information and education, and avoid negative messaging or judgment of what students eat, may be more acceptable.
A narrative review of the construct of hedonic hunger and its measurement by the Power of Food Scale
Authors: Espel‐Huynh H. M. , Muratore A. F. , Lowe M. R.
Published: February 2018

Introduction

The term ‘hedonic hunger’ refers to one's preoccupation with and desire to consume foods for the purposes of pleasure and in the absence of physical hunger. The Power of Food Scale (PFS) was developed as a quantitative measure of this construct in 2009. Since then, over 50 published studies have used the PFS to predict appetite‐related outcomes including neural, cognitive, behavioural, anthropometric and clinical measures.

Objective

This narrative review evaluates how closely the PFS captures the construct it was originally presumed to assess and to more clearly define hedonic hunger itself.

Methods

The measure's relationship to four domains is reviewed and summarized: motivation to consume palatable foods; level of actual consumption of such foods; body mass; and subjective loss‐of‐control over one's eating behaviour. Findings are synthesized to generate a more accurate understanding of what the PFS measures and how it may relate to the broader definition of hedonic hunger.

Results

Results suggest that the PFS is closely related to motivation to consume palatable foods and, in extreme cases, occurrence of loss‐of‐control eating episodes. PFS scores are not consistently predictive of amount of food consumed or body mass.

Conclusions

Implications of these findings are discussed in the context of behavioural health, and avenues for further inquiry are identified.
Organizational control rationales in knowledge‐intensive organizations: An integrative review of emerging trends
Authors: Martin‐Rios Carlos
Published: February 2018

This theoretical paper uses a complete review of organizational control configuration (OCC) literature to illustrate the innovation, complexity and dynamics of control in knowledge‐intensive organizations (KIOs). On the basis of interdisciplinary analysis of the extant literature on OCC, the paper offers a comprehensive look at the “control pathway” taken by the various KIOs. By means of this integrative review of existing theory and research, the paper argues for greater attention to KIOs' control rationales in OCC theory and research. In doing so, it offers a comprehensive conceptual framework for the study of control in KIOs and suggests a number of propositions for future research.
An exploration of the application of universities as artificial institutional entrepreneurs: The case of China
Authors: Zheng Connie , Hu Mei‐Chih
Published: February 2018

Universities worldwide have increasingly been encouraged to incubate and create business enterprises in order to fulfil national and regional economic development objectives via rapid research commercialization, technology transfer, and open innovation. The definitions of university‐level entrepreneurship appear to be controversial in the extant literature, with special reference to government–university–industry partnerships under the overarching theoretical framework of institutional entrepreneurship. No longer do universities act only as agents for knowledge transmission and diffusion but also as business enterprises to help change formal institutional arrangements to meet evolving economic and social demands and to graft the entrepreneurial paradigm into academic culture and structures. As a transitional economy, have China's universities also acted as institutional entrepreneurs for change? In this paper, we address this research question by exploring the nature of government–university–industry links and the application of “institutional entrepreneurship” to Chinese universities. We use a case analysis of the Industry Technology Research Institute of Geo‐Resources and Environment Co. Ltd. established by the China University of Geosciences to support our argument that Chinese universities are artificial institutional entrepreneurs. As a result of our analysis, we identified several success factors and constraints on universities as institutional entrepreneurs in the context of China.
Paying for Happiness: Experimental Results from a Large Cash Transfer Program in Malawi
Authors: Kilburn Kelly , Handa Sudhanshu , Angeles Gustavo , Tsoka Maxton , Mvula Peter
Published: February 2018

This study analyzes the short‐term impact of an exogenous, positive income shock on caregivers’ subjective well‐being (SWB) in Malawi using panel data from 3,365 households targeted to receive Malawi's Social Cash Transfer Program that provides unconditional cash to ultra‐poor, labor‐constrained households. The study consists of a cluster‐randomized, longitudinal design. After the baseline survey, half of these village clusters were randomly selected to receive the transfer and a follow‐up was conducted 17 months later. We find that the short‐term impact of household income increases from the cash transfer leads to substantial SWB gains among caregivers. After a year's worth of transfers, caregivers in beneficiary households have higher life satisfaction and are more likely to believe in a better future. We examine whether program impacts on consumption, food security, resilience, and hopefulness could explain the increase in SWB but do not find that any of these mechanisms individually mediate our results.
THE INTERNAL AND EXTERNAL VALIDITY OF THE REGRESSION DISCONTINUITY DESIGN: A META‐ANALYSIS OF 15 WITHIN‐STUDY COMPARISONS
Authors: Chaplin Duncan D. , Cook Thomas D. , Zurovac Jelena , Coopersmith Jared S. , Finucane Mariel M. , Vollmer Lauren N. , Morris Rebecca E.
Published: February 2018

Theory predicts that regression discontinuity (RD) provides valid causal inference at the cutoff score that determines treatment assignment. One purpose of this paper is to test RD's internal validity across 15 studies. Each of them assesses the correspondence between causal estimates from an RD study and a randomized control trial (RCT) when the estimates are made at the same cutoff point where they should not differ asymptotically. However, statistical error, imperfect design implementation, and a plethora of different possible analysis options, mean that they might nonetheless differ. We test whether they do, assuming that the bias potential is greater with RDs than RCTs. A second purpose of this paper is to investigate the external validity of RD by exploring how the size of the bias estimates varies across the 15 studies, for they differ in their settings, interventions, analyses, and implementation details. Both Bayesian and frequentist meta‐analysis methods show that the RD bias is below 0.01 standard deviations on average, indicating RD's high internal validity. When the study‐specific estimates are shrunken to capitalize on the information the other studies provide, all the RD causal estimates fall within 0.07 standard deviations of their RCT counterparts, now indicating high external validity. With unshrunken estimates, the mean RD bias is still essentially zero, but the distribution of RD bias estimates is less tight, especially with smaller samples and when parametric RD analyses are used.
Conductive poly(3,4‐ethylenedioxythiophene): poly(styrene sulfonate) polymer glue as an ohmic and rectifying electrical contact for H‐terminated n‐Si and p‐Si wafers
Authors: Cohen Daniel , Bostian Micah E , Nguyen Li , Walter Michael G
Published: February 2018

An organic conductive glue based on a blend of poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and d‐sorbitol was examined for laminating conductors to crystalline silicon. The PEDOT:PSS glue functions as a high‐work‐function solution processable conductor and exhibits an ohmic contact on p‐type silicon and a rectifying contact on n‐type silicon. Under illumination, the n‐Si/PEDOT:PSS:d‐sorbitol junctions exhibit current–voltage characteristics suggesting minority carrier trap states, leading to charge recombination at the silicon/polymer interface. Conductive glue for laminating to crystalline silicon is desirable for making electrical contacts to flexible materials such as molecular semiconductors, graphene or transparent conductive oxides. These materials could eliminate the need for metal contacts to the front face of silicon solar cells. Conductive glue could prove especially useful for laminating to textured silicon or novel micro‐ or nanostructured silicon materials. © 2018 Society of Chemical Industry
Optical properties and performance of pyramidal texture silicon heterojunction solar cells: Key role of vertex angles
Authors: Mrazkova Zuzana , Sobkowicz Igor Paul , Foldyna Martin , Postava Kamil , Florea Ileana , Pištora Jaromír , Roca i Cabarrocas Pere
Published: February 2018

Silicon heterojunction solar cells with pyramidal textured surfaces created by different etching conditions and their properties related to device efficiency (short‐circuit current density and open‐circuit voltage) are studied. An easy‐to‐apply model is proposed to estimate reflection losses, optimize the multilayer structure of the solar cell, and enhance photovoltaic conversion efficiency. The effects of etching treatments and pyramid geometry on overall device performance are discussed in detail. The study is completed by measurement of pyramid vertex angles of different textures. A difference from the expected and generally accepted theoretical value of 70.52° is demonstrated and explained based on observation from high‐resolution transmission electron microscopy. The multilayer structure of silicon heterojunction solar cells is optimized with respect to various pyramid vertex angles, using the designed optical model to minimize absorption and reflection losses.
Mechanistic aspects on molecular structure formation of polymeric networks from diisocyanates with amidine compounds
Authors: Laue Andreas , Uhlig Daniel , Fiedler Benjamin , Friedrich Joachim , Mende Carola , Kroll Lothar , Spange Stefan
Published: February 2018

Polymeric networks are produced by step‐growth polyaddition and co‐polyaddition reactions of 1‐ethylimidazoline in combination with various diisocyanates. Five aromatic, two aliphatic diisocyanates and a polyurethane prepolymer are used as particular reactant in N,N‐dimethylformamide as solvent at room temperature. Obviously, 1‐ethylimidazoline can serve as trifunctional monomer, which enables a crosslinking reaction with diisocyanates. Molecular structure elements of the polymeric networks were studied by solid state 13C‐NMR spectroscopy revealing that detailed molecular structure formations are determined whether aromatic or aliphatic diisocyanates are used. Quantum chemical calculations were used as supporting method to elucidate the complex reaction cascades. Hence, it can be shown that beside 3:1 stoichiometric structures 2:1 based structures are formed as well. These structures are observed as kinetically controlled products only when aromatic diisocyanate monomers are used. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 977–985
Dithienylmethanone‐Based Cross‐Conjugated Polymer Semiconductors: Synthesis, Characterization, and Application in Field‐Effect Transistors
Authors: Shi Keli , Zhang Weifeng , Wei Congyuan , Lin Zuzhang , Liu Xiaotong , Yu Gui
Published: February 2018

Herein, we report the synthesis, characterization, and field‐effect properties of two cross‐conjugated dithienylmethanone (DMO)‐based alternating polymers, namely, PDMO‐S and PDMO‐Se. Both polymers possess high thermal stability, good solubility, and broad absorption spectra. Their electrochemical properties were investigated using cyclic voltammetry, indicating that PDMO‐Se has higher HOMO/LUMO energy levels of −5.49/−3.49 eV than −5.57/−3.58 eV of PDMO‐S. The two polymers exhibited promising charge transport properties with the highest hole mobility of 0.12 cm2 V−1 s−1 for PDMO‐S and 0.025 cm2 V−1 s−1 for PDMO‐Se. AFM and 2D‐GIXRD analyses demonstrated that the PDMO‐S formed lamellar, edge‐on packing thin film with close π‐π stacking. These findings suggest that cross‐conjugated polymers might be potential semiconducting materials for low‐cost and flexible organic electronics. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1012–1019
The Glycoproteomics–MS for Studying Glycosylation in Cardiac Hypertrophy and Heart Failure
Authors: Yang Shuang , Chatterjee Subroto , Cipollo John
Published: February 2018

With recent advancements of analytical techniques and mass spectrometric instrumentations, proteomics has been widely exploited to study the regulation of protein expression associated with disease states. Many proteins may undergo abnormal change in response to the stimulants, leading to regulation of posttranslationally modified proteins. In this review, the physiological and pathological roles of protein glycosylation in cardiac hypertrophy is discussed, and how the signal pathways regulate heart function and leading to heart failure. The analytical methods for analysis of protein glycosylation, including glycans, glycosite, occupancy, and heterogeneity is emphasized. The rationale on glycoproteins as disease biomarkers is also discussed. The authors also propose potential research in this field and challenges in the diagnosis and treatment of this disease.
The ω‐transaminase engineering database (oTAED): A navigation tool in protein sequence and structure space
Authors: Buß Oliver , Buchholz Patrick C. F. , Gräff Maike , Klausmann Peter , Rudat Jens , Pleiss Jürgen
Published: February 2018

The ω‐Transaminase Engineering Database (oTAED) was established as a publicly accessible resource on sequences and structures of the biotechnologically relevant ω‐transaminases (ω‐TAs) from Fold types I and IV. The oTAED integrates sequence and structure data, provides a classification based on fold type and sequence similarity, and applies a standard numbering scheme to identify equivalent positions in homologous proteins. The oTAED includes 67 210 proteins (114 655 sequences) which are divided into 169 homologous families based on global sequence similarity. The 44 and 39 highly conserved positions which were identified in Fold type I and IV, respectively, include the known catalytic residues and a large fraction of glycines and prolines in loop regions, which might have a role in protein folding and stability. However, for most of the conserved positions the function is still unknown. Literature information on positions that mediate substrate specificity and stereoselectivity was systematically examined. The standard numbering schemes revealed that many positions which have been described in different enzymes are structurally equivalent. For some positions, multiple functional roles have been suggested based on experimental data in different enzymes. The proposed standard numbering schemes for Fold type I and IV ω‐TAs assist with analysis of literature data, facilitate annotation of ω‐TAs, support prediction of promising mutation sites, and enable navigation in ω‐TA sequence space. Thus, it is a useful tool for enzyme engineering and the selection of novel ω‐TA candidates with desired biochemical properties.
Longitudinal assessment of the impact of multiple switches between a biosimilar and its reference product on efficacy parameters
Authors: Mielke Johanna , Woehling Heike , Jones Byron
Published: February 2018

Patients, physicians, and health care providers in Europe have more than 10 years of experience with biosimilars. However, there are still debates if switching between a biosimilar and its reference product influences the efficacy of the treatment. In this paper, we address this uncertainty by developing a formal statistical test that can be used for showing that switching has no negative impact on the efficacy of biosimilars. For that, we first introduce a linear mixed‐effects model that is used for defining the null hypothesis (switching influences the efficacy) and the alternative hypothesis (switching has no influence on the efficacy). Using this as the foundation of our work, we propose several approaches for testing for changes in the efficacy of the treatment due to switching and discuss the properties of these tests in an extensive simulation study. It is shown that all these methods have advantages and disadvantages and the decision regarding which method is preferred depends on the expectation of a switching assessment. To demonstrate the applicability of the methods in practice, the approaches were applied to the data of the EGALITY study, which compares the reference product Enbrel® (Amgen) with the approved biosimilar Erelzi® (Sandoz).
Why don't SSRIs work in the medical subspecialty clinic?
Authors: Price Lawrence H.
Published: February 2018

During a recent supervision session with a resident, the question arose as to whether the diazepam being given to one of his clinic patients with chronic renal insufficiency should be replaced by a benzodiazepine that was either shorter‐acting or without active metabolites (the answer: probably unnecessary, since most of diazepam's metabolism is hepatic). Quite by coincidence, results of the Chronic Kidney Disease Antidepressant Sertraline Trial (CAST) had just been published by Hedayati et al., allowing our supervision discussion to meander onto a related, and probably more important, topic: What is the best way to treat depression in the medically compromised?
The effect of potential vorticity fluxes on the circulation of the tropical upper troposphere
Authors: Ortega Sebastián , Webster Peter J. , Toma Violeta , Chang Hai‐Ru
Published: February 2018

With simple analytical arguments, we suggest that the subtropical westerly jets, the equatorial easterly winds, the westerly ducts (i.e. regions of westerly winds over the Equator), and the tropical upper tropospheric troughs, are coupled via potential vorticity (PV) dynamics. We suggest that deep tropical convection leads to advective PV fluxes towards the Poles over the subtropical westerly jets, triggering Rossby waves on the jet, and leading to advective PV fluxes towards the Equator when the Rossby waves break over the westerly ducts. Moreover, we show that the advective PV fluxes towards the Poles closely balance those towards the Equator, and suggest that this close balance is to be expected from the impermeability theorem. We then argue that small imbalances of these advective PV fluxes play an important role in maintaining the upper tropospheric mean flow of the tropical atmosphere.

We test our ideas using a shallow‐water model of the atmosphere, where diabatic heating terms are absent, and show how imbalances in the advective PV fluxes of a shallow‐water model maintain its mean flow. We focus on the periodicity of the shallow‐water models to study the effect of transient eddies and relate our results to previous studies.
Tuning thermal stability and electronic properties of germanium oxide on Ge(001) surface with the incorporation of nitrogen
Authors: Yang Yu Lin
Published: February 2018

The application of germanium as a channel material of transistors in near future requires an improved understanding of the interface between germanium and its potential passivation layer. In this study, we study effects of nitrogen incorporation on the thermal stability and electronic properties of GeOxNy/Ge interface by using high‐resolution X‐ray photoemission spectroscopy. We find that with the increasing nitrogen concentration in the GeOxNy films, the thermal stability can be increased, while the valence band offset with the Ge(001)substrate is decreased. First‐principles calculations further suggest that the unpaired p orbitals of nitrogen atoms induce electronic states near valence band edge, contributing to the reduction of the valence band offset. Our results provide a possibility to tune electronic and thermal properties of GeOxNy/Ge interface by controlling nitrogen concentrations during the growth.
High Efficient Cu2O/TiO2 Nanocomposite Photocatalyst to Degrade Organic Polluant under Visible Light Irradiation
Authors: Ding Ruocheng C. , Fan Yuzun Z. , Wang Guangsheng S.
Published: February 2018

The enhanced photocatalytic properties of Cu2O/TiO2 nanocomposites resulting from the synthesis of uniform p‐type Cu2O and n‐type TiO2 via wet chemical method were studied. The nanocomposite also had been well characterized and tested for its photocatalytic activity. These results indicate that the photocatalytic performance of the composites is clearly improved. The degradation rate of methylene blue solution (10 mg/L) increased to 93.67% in 45 minutes. The p‐n heterojunction theory was used to explain the enhanced photocatalytic properties. The photocatalytic performances of Cu2O/TiO2 nanocomposites and its photoreaction mechanism were proposed and discussed in this work.
Oxidative Coupling of Naphthols to Ketones: An Approach to 1,2‐Diketones
Authors: Deb Mohit L. , Saikia B‐Shriya , Rastogi Gaurav K. , Baruah Pranjal K.
Published: February 2018

1,2‐Diketones are highly useful building blocks for the synthesis of pharmaceuticals, natural products and heterocycles. A simple and efficient route to 1,2‐diketones is developed here. The strategy involves coupling of naphthols to methyl ketones via oxidative C−H functionalization of methyl group of ketones. CuI (10 mol %) is used as catalyst and FeSO4.7H2O (10 mol %) as additive, both of which are environmentally benign and cheap. The reaction is carried out in DMSO solvent at 120 oC for 8–10 h. Little amount of 1,1′‐bi‐2‐naphthol (BINOL) is also formed as side product. A tentative mechanism is proposed for the reaction which demonstrates a free‐radical pathway. Although Cu(I) is used as catalyst, however, the in situ generated Cu(II) behaves as the active catalytic species. Aerial oxygen acts as the oxygen source for the newly formed carbonyl functional group.
Rh/DNA Nanoparticles, Synthesis, Characterization and Catalytic Activity in “On Water” Asymmetric Hydroformylation Reaction
Authors: Alsalahi Waleed , Trzeciak Anna M.
Published: February 2018

DNA‐stabilized Rh NPs were synthesized by the chemical reduction of Rh(acac)(CO)2 (acac=acetylacetonate) in water at 80 °C. The obtained nanoparticles, Rh/DNA, were characterized by various spectroscopic and microscopic methods, such as IR, UV‐Vis, XRD (X‐ray diffraction), ICP‐AES (Inductively coupled plasma atomic emission spectroscopy), EDX (Energy‐dispersive X‐ray spectroscopy analysis), TEM (Transmission electron microscopy), and SEM (Scanning electron microscopy) analyses. Their catalytic activity was successfully investigated in the “on water” hydroformylation of styrene. The conversion of styrene and chemoselectivity towards aldehydes were 100%. A high iso/n ratio was also obtained, up to 6.1 and 16.7 with PPh3 (triphenylphosphine) and (R)‐BINAP (2,2′‐bis(diphenylphosphino)‐1,1′‐binaphthyl) ligands respectively. In the hydroformylation of vinyl acetate with Rh/DNA, performed in the presence of a chiral BINAP ligand “on water”, high enantioselectivity was obtained, up to 49% ee. These results were significantly better than when utilizing Rh(acac)(CO)2 as a catalyst under the same conditions.
Highly Efficient and Stable Flexible Perovskite Solar Cells with Metal Oxides Nanoparticle Charge Extraction Layers
Authors: Najafi Mehrdad , Di Giacomo Francesco , Zhang Dong , Shanmugam Santhosh , Senes Alessia , Verhees Wiljan , Hadipour Afshin , Galagan Yulia , Aernouts Tom , Veenstra Sjoerd , Andriessen Ronn
Published: February 2018

In this study, the fabrication of highly efficient and durable flexible inverted perovskite solar cells (PSCs) is reported. Presynthesized, solution‐derived NiOx and ZnO nanoparticles films are employed at room temperature as a hole transport layer (HTL) and electron transport layer (ETL), respectively. The triple cation perovskite films are produced in a single step and for the sake of comparison, ultrasmooth and pinhole‐free absorbing layers are also fabricated using MAPbI3 perovskite. The triple cation perovskite cells exhibit champion power conversion efficiencies (PCEs) of 18.6% with high stabilized power conversion efficiency of 17.7% on rigid glass/indium tin oxide (ITO) substrates (comparing with 16.6% PCE with 16.1% stabilized output efficiency for the flexible polyethylene naphthalate (PEN)/thin film barrier/ITO substrates). More interestingly, the durability of flexible PSC under simulation of operative condition is proved. Over 85% of the maximum stabilized output efficiency is retained after 1000 h aging employing a thin MAPbI3 perovskite (over 90% after 500 h with a thick triple cation perovskite). This result is comparable to a similar state of the art rigid PSC and represents a breakthrough in the stability of flexible PSC using ETLs and HTLs compatible with roll to roll production speed, thanks to their room temperature processing.
In Situ Oxidation Synthesis of p‐Type Composite with Narrow‐Bandgap Small Organic Molecule Coating on Single‐Walled Carbon Nanotube: Flexible Film and Thermoelectric Performance
Authors: Gao Caiyan , Chen Guangming
Published: February 2018

Although composites of organic polymers or n‐type small molecule/carbon nanotube (CNT) have achieved significant advances in thermoelectric (TE) applications, p‐type TE composites of small organic molecules as thick surface coating layers on the surfaces of inorganic nanoparticles still remain a great challenge. Taking advantage of in situ oxidation reaction of thieno[3,4‐b]pyrazine (TP) into TP di‐N‐oxide (TPNO) on single‐walled CNT (SWCNT) surface, a novel synthesis strategy is proposed to achieve flexible films of TE composites with narrow‐bandgap (1.19 eV) small molecule coating on SWCNT surface. The TE performance can be effectively enhanced and conveniently tuned by poly(sodium‐p‐styrenesulfonate) content, TPNO/SWCNT mass ratio, and posttreatment by various polar solvents. The maximum of the composite power factor at room temperature is 29.4 ± 1.0 µW m−1 K−2. The work presents a way to achieve flexible films of p‐type small organic molecule/inorganic composites with clear surface coating morphology for TE application.