bluuebunny/crossref_metadata_2025 huggingface dataset:
Physico‐mechanical and tribological properties of nanoclay filled friction composite materials using Taguchi design of experiment approach
Authors: Singh Tej , Patnaik Amar , Chauhan Ranchan , Chauhan Pankit , Kumar Naresh
Published: June 2016

In this article, nanoclay filled organic–inorganic fiber reinforced brake friction composites are designed, fabricated by compression molding and then investigated their physical, chemical, mechanical, and tribological properties. It is observed that density of the composites increased due to incorporation of inorganic contents (nanoclay/lapinus), which are quite heavier than organic contents (Kevlar/graphite) in the composites. Similarly, as far as mechanical properties are concerned the hardness, tensile strength, and flexural strength of the composites increased with the decrease in the nanoclay/lapinus fiber content but at the same time the organic contents, that is, both Kevlar fiber and graphite content are in the increased order of proportionality. Finally, Taguchi design of experiment technique (L16 orthogonal array design) is implemented to evaluate the optimal factor settings simultaneously wear loss of the brake friction composites. In this experimental analysis, four input control factors have been taken such as composition, load, Speed, and distance at four levels each to obtain the wear rate and coefficient of friction of the fiber reinforced brake friction composites. The overall mean for the signal‐to‐noise (S/N) ratio of the coefficient of friction and wear rate of the brake friction composites is found to be −9.20 and 96.72 db, respectively. At the end, a confirmation experiment is conducted between the experimental result and predicted theoretical result in order to validate the experimental result. POLYM. COMPOS., 39:1575–1581, 2018. © 2016 Society of Plastics Engineers
Effect of supercritical CO2 on the copolymerization behavior of cyclohexene oxide/CO2 and copolymer properties with DMC/Salen‐Co(III) catalyst system
Authors: Meng Qing‐Yang , Pepper Katie , Cheng Rui‐Hua , Howdle Steven M. , Liu Bo‐Ping
Published: June 2016

The copolymerization of cyclohexene oxide (CHO) and carbon dioxide (CO2) was carried out under supercritical CO2 (scCO2) conditions to afford poly (cyclohexene carbonate) (PCHC) in high yield. The scCO2 provided not only the C1 feedstock but also proved to be a very efficient solvent and processing aid for this copolymerization system. Double metal cyanide (DMC) and salen‐Co(III) catalysts were employed, demonstrating excellent CO2/CHO copolymerization with high yield and high selectivity. Surprisingly, our use of scCO2 was found to significantly enhance the copolymerization efficiency and the quality of the final polymer product. Thermally stable and high molecular weight (MW) copolymers were successfully obtained. Optimization led to excellent catalyst yield (656 wt/wt, polymer/catalyst) and selectivity (over 96% toward polycarbonate) that were significantly beyond what could be achieved in conventional solvents. Moreover, detailed thermal analyses demonstrated that the PCHC copolymer produced in scCO2 exhibited higher glass transition temperatures (Tg ∼ 114 °C) compared to polymer formed in dense phase CO2 (Tg ∼ 77 °C), and hence good thermal stability. Additionally, residual catalyst could be removed from the final polymer using scCO2, pointing toward a green method that avoids the use of conventional volatile organic‐based solvents for both synthesis and work‐up. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2785–2793
Negative linear compressibility from rotating rigid units
Authors: Attard Daphne , Caruana‐Gauci Roberto , Gatt Ruben , Grima Joseph N.
Published: June 2016

The possibility of achieving the anomalous property of negative linear compressibility through a mechanism involving the rotations of rigid units is presented and discussed through analytical modelling. It is shown that some rotating rigid units with particular geometric features and connectivities will expand rather than contract in certain directions when a hydrostatic pressure is applied. The conditions required for this anomalous property to be achieved via rotations are elucidated in terms of specific geometric and structural requirements as well as their Poisson's ratio and stiffness properties.
Phonon‐assisted tunnel emission of holes from the double donor level of the EL2 defect
Authors: Wosinski Tadeusz
Published: June 2016

Strong electric‐field‐induced enhancement of the thermal emission rate of holes from the doubly ionised charge state of the ΕL2 defect was revealed with the double‐correlation deep‐level transient spectroscopy in p‐type GaAs crystals of various crystallographic orientations. The observed enhancement, by over four orders of magnitude of the emission rate, was analysed in a model of phonon‐assisted tunnel ionisation. Similar dependences of the hole‐emission rate on the electric‐field intensity received for the electric‐field directions parallel to three main crystallographic axes evidence for tetrahedral symmetry of the defect, which is consistent with its identification as the isolated arsenic antisite defect.
Outlook and Challenges of Nanotechnologies for Food Packaging
Authors: Wyser Yves , Adams Michael , Avella Maurizio , Carlander David , Garcia Leonor , Pieper Gabriele , Rennen Monique , Schuermans Jeroen , Weiss Jochen
Published: June 2016

Nanotechnology has been considered to have high potential for food packaging applications very early on. The ability to provide additional consumer benefits through the improvement of key properties of packaging materials and the creation of new functionalities means that the increased use of nanomaterials and nanotechnologies is highly likely. It has however up to now failed to reach the widespread use that was initially expected, mainly because of remaining uncertainties on the safety of these materials during the various stages of their life‐cycle, which limit legal and consumer acceptance.

This paper aims at presenting the latest developments in the field of nanotechnologies for food packaging applications, describing the legal framework linked to their usage and attempts to clarify the current knowledge of the safety of these materials both for the consumer and the environment.

It is shown that particulate migration into foodstuff is absent in many applications, which drastically reduces the potential risk during the use phase of packaging materials, i.e. the exposure of the consumer to nanoparticles. Other release routes are also evaluated, showing that, although safe in normal use conditions, prudence should still be used, especially with regard to release after disposal of the materials. Copyright © 2016 The Authors Packaging Technology and Science Published by John Wiley & Sons Ltd
Convective initiation and maintenance processes of two back‐building mesoscale convective systems leading to heavy precipitation events in Southern Italy during HyMeX IOP 13
Authors: Lee K.‐O. , Flamant C. , Ducrocq V. , Duffourg F. , Fourrié N. , Davolio S.
Published: June 2016

During Intensive Observation Period 13 (15 to 16 October 2012) of the first Special Observing Period of the Hydrological cycle in the Mediterranean Experiment (HyMeX), Southern Italy (SI) was affected by two consecutive heavy precipitation events (HPEs). Both HPEs were associated with multi‐cell V‐shaped retrograde regeneration mesoscale convective systems (MCSs). The life cycle of two MCSs in connection with their dynamic and thermodynamic environments were analysed using a combination of ground‐based, airborne and spaceborne observations and numerical simulations. Rain gauges revealed that heavy precipitation occurred in two phases: the first one from 1300 to 1700 UTC (35 mm h−1) was caused by a V‐shaped system initiating over the Tyrrhenian Sea in the early morning of 15 October. Convection was triggered by the low‐level convergence between the southwesterlies ahead of an upper‐level trough positioned over southeastern France and very moist southerlies from the Strait of Sicily. The convection was favoured by high convective available potential energy (1500 J kg−1) resulting from warm and moist conditions at low levels associated with high sea surface temperatures in the Strait of Sicily. In addition, humidity at mid‐level was enriched by the presence of an elevated moisture plume from tropical Africa, favouring the efficiency of the convection to produce more precipitation. The second phase of heavy precipitation (2300 UTC on 15 October to 0200 UTC on 16 October, 34 mm h−1) was caused by a MCS initiating over Algeria around 1300 UTC, which subsequently travelled over the Strait of Sicily toward Sicily and SI. Convection was maintained by the combination of large low‐level moisture contents and a marked convergence ahead of the cold front. Unlike other MCSs forming in the same region earlier on that day, this huge V‐shaped system did affect SI because the strong upper‐level flow progressively backed from southwesterly to south southwesterly.
Comparing results from multiple imputation and dynamic marginal structural models for estimating when to start antiretroviral therapy
Authors: Shepherd Bryan E. , Liu Qi , Mercaldo Nathaniel , Jenkins Cathy A. , Lau Bryan , Cole Stephen R. , Saag Michael S. , Sterling Timothy R.
Published: June 2016

Optimal timing of initiating antiretroviral therapy has been a controversial topic in HIV research. Two highly publicized studies applied different analytical approaches, a dynamic marginal structural model and a multiple imputation method, to different observational databases and came up with different conclusions. Discrepancies between the two studies' results could be due to differences between patient populations, fundamental differences between statistical methods, or differences between implementation details. For example, the two studies adjusted for different covariates, compared different thresholds, and had different criteria for qualifying measurements. If both analytical approaches were applied to the same cohort holding technical details constant, would their results be similar? In this study, we applied both statistical approaches using observational data from 12,708 HIV‐infected persons throughout the USA. We held technical details constant between the two methods and then repeated analyses varying technical details to understand what impact they had on findings. We also present results applying both approaches to simulated data. Results were similar, although not identical, when technical details were held constant between the two statistical methods. Confidence intervals for the dynamic marginal structural model tended to be wider than those from the imputation approach, although this may have been due in part to additional external data used in the imputation analysis. We also consider differences in the estimands, required data, and assumptions of the two statistical methods. Our study provides insights into assessing optimal dynamic treatment regimes in the context of starting antiretroviral therapy and in more general settings. Copyright © 2016 John Wiley & Sons, Ltd.
Facile Synthesis and Electrochemical Evaluation of Coumarin‐Tagged Pyridine and Thiophene Derivatives
Authors: Alharthy Rima D. , Hameed Abdul , Rashida Mariya al‐ , Al‐Moubaraki Aisha , Al‐Mhyawi Saedah R.
Published: June 2016

A series of coumarin pyridinethiones and pyridinones has been synthesized employing a range of substituted cyanothioacetamides and cyanoacetamides intermediates. Coumarin pyridinethiones and pyridinones bear different substituents including electron donating groups such as methyl, methoxy dimethylamine in addition to chloro, bromo and nitro as electron withdrawing groups were chosen to study the structure/electrochemical relationship. The influence of electron donating group and electron withdrawing group on different positions of coumarin scaffold was studied utilizing cyclic voltammetry and controlled potential electrolysis at platinum and glassy carbon electrodes. The electrochemical redox mechanisms of synthesized coumarins were proposed and the oxidation and reduction pathways were determined. Data for cyclic voltammetry and controlled potential electrolysis proved that amine center served as the oxidation center, while thiocarbonyl and carbonyl groups were identified as the reduction centers.
A Novel Enzymatic Strategy for the Synthesis of Substituted Tetrahydroisoquinolines
Authors: Bonamore Alessandra , Calisti Lorenzo , Calcaterra Andrea , Ismail Omar H. , Gargano Maurizio , D'Acquarica Ilaria , Botta Bruno , Boffi Alberto , Macone Alberto
Published: June 2016

A fully enzymatic asymmetric synthesis of substituted tetrahydroisoquinolines was achieved in two steps starting from dopamine and a set of amine substrates by coupling the activity of a plant diamine oxidase with the recombinant norcoclaurine synthase enzyme from Thalictrum flavum. In the first step, a variety of aliphatic and aromatic amines of general interest as pharmaceutical building blocks were transformed into the corresponding aldehydes by the broad specificity of diamine oxidase enzyme from Lathyrus cicera. In the second step, the stereoselectivity of the norcoclaurine synthase catalyzed reaction to yield (S)‐configured tetrahydroisoquinoline products was exploited by mixing the aldehyde obtained in the first step with dopamine, the committed substrate for the Pictet‐Spengler reaction. The reactions were carried out in aqueous buffer and the products thus obtained were extracted and characterized by chiral GC/MS. Enantiomeric excess > 99% were obtained for all substrates investigated. The method provided a set of novel tetrahydroisoquinolines with potentially interesting pharmacological profiles.
Selective Colorimetric Sensor for the Detection of Hg2+ and H2S in Aqueous Medium and Waste Water Samples
Authors: Kaushik Rahul , Singh Ajeet , Ghosh Amrita , Jose D. Amilan
Published: June 2016

Dabsyl based new colorimetric sensor 1 for the selective detection of environmentally most important cation Hg2+ and biologically important hydrogen sulfide (H2S) in aqueous medium have been reported. The probe 1 selectively responded to Hg2+ among various cations and shows colour change from yellow to red with the bathochromic shift in Uv‐Vis spectrum via intramolecular charge transfer (ICT) mechanism. The limit of detection for mercury was determined as 80 μM. The possibility of using 1 to detect mercury in industrial waste water samples was also explored with good recovery value. The ensemble 1.Hg2+, also applicable for the detection of H2S (LOD = 28 μM) in water among different bio‐thiols and anions. H2S displaces the mercury from 1.Hg2+ via metal displacement approach and regenerates the original probe 1 within few seconds. Regenerated receptor 1, further used for the detection of mercury ion. Receptor 1 incorporated test paper and polymer based thin films were used as a portable kit for the selective colorimetric detection of mercury and H2S in water.
Thiacalix[4]arene Derivatives Bearing Imidazole Units: A Ditopic Hard/Soft Receptor for Na+ and K+/Ag+ with an Allosteric Effect and a Reusable Extractant for Dichromate Anions
Authors: Zhao Jiang‐Lin , Wu Chong , Zeng Xi , Rahman Shofiur , Georghiou Paris E. , Elsegood Mark R. J. , Warwick Mr. Thomas G. , Redshaw Carl , Teat Simon J. , Yamato Takehiko
Published: June 2016

Two novel receptors 5,11,17,23‐tetra‐tert‐butyl‐25,27‐bis[(ethoxycarbonyl)methoxy]‐26,28‐bis‐[1‐methyl‐(imidazole)meth‐oxy]‐2,8,14,20‐tetra‐thiacalix[4]arene (L1) and 5,11,17,23‐tetra‐tert‐butyl‐25,27‐bis‐[(benzyl)methoxy]‐26,28‐bis‐[1‐methyl‐(imidazole)‐methoxy]‐2,8,14,20‐tetrathiacalix[4]arene (L2) possessing imidazole moieties based on thiacalix[4]arene in the 1,3‐alternate conformation have been synthesized and characterized. The crystal structures of L1 and L2 have been determined. The binding behaviour towards Li+, Na+, K+ and Ag+ ions has been examined by 1H NMR titration experiments in (CDCl3/CD3CN; 10:1, v/v) solution. The exclusive formation of mononuclear complexes of L1 with metal cations is of particular interest revealing a negative allosteric effect in the thiacalix[4]arene family. Liquid‐liquid extraction experiments indicate that synthesized L2 can be utilized as an efficient reusable extractant for dichromate anion by controlling the pH of the aqueous solution.
Integration of Artificial Photosynthesis System for Enhanced Electronic Energy‐Transfer Efficacy: A Case Study for Solar‐Energy Driven Bioconversion of Carbon Dioxide to Methanol
Authors: Ji Xiaoyuan , Su Zhiguo , Wang Ping , Ma Guanghui , Zhang Songping
Published: June 2016

Biocatalyzed artificial photosynthesis systems provide a promising strategy to store solar energy in a great variety of chemicals. However, the lack of direct interface between the light‐capturing components and the oxidoreductase generally hinders the trafficking of the chemicals and photo‐excited electrons into the active center of the redox biocatalysts. To address this problem, a completely integrated artificial photosynthesis system for enhanced electronic energy‐transfer efficacy is reported by combining co‐axial electrospinning/electrospray and layer‐by‐layer (LbL) self‐assembly. The biocatalysis part including multiple oxidoreductases and coenzymes NAD(H) was in situ encapsulated inside the lumen polyelectrolyte‐doped hollow nanofibers or microcapsules fabricated via co‐axial electrospinning/electrospray; while the precise and spatial arrangement of the photocatalysis part, including electron mediator and photosensitizer for photo‐regeneration of the coenzyme, was achieved by ion‐exchange interaction‐driven LbL self‐assembly. The feasibility and advantages of this integrated artificial photosynthesis system is fully demonstrated by the catalyzed cascade reduction of CO2 to methanol by three dehydrogenases (formate, formaldehyde, and alcohol dehydrogenases), incorporating the photo‐regeneration of NADH under visible‐light irradiation. Compared to solution‐based systems, the methanol yield increases from 35.6% to 90.6% using the integrated artificial photosynthesis. This work provides a novel platform for the efficient and sustained production of a broad range of chemicals and fuels from sunlight.
Encapsulation of Single Plasmonic Nanoparticles within ZIF‐8 and SERS Analysis of the MOF Flexibility
Authors: Zheng Guangchao , de Marchi Sarah , López‐Puente Vanesa , Sentosun Kadir , Polavarapu Lakshminarayana , Pérez‐Juste Ignacio , Hill Eric H. , Bals Sara , Liz‐Marzán Luis M. , Pastoriza‐Santos Isabel , Pérez‐Juste Jorge
Published: June 2016

Hybrid nanostructures composed of metal nanoparticles and metal‐organic frameworks (MOFs) have recently received increasing attention toward various applications due to the combination of optical and catalytic properties of nanometals with the large internal surface area, tunable crystal porosity and unique chemical properties of MOFs. Encapsulation of metal nanoparticles of well‐defined shapes into porous MOFs in a core–shell type configuration can thus lead to enhanced stability and selectivity in applications such as sensing or catalysis. In this study, the encapsulation of single noble metal nanoparticles with arbitrary shapes within zeolitic imidazolate‐based metal organic frameworks (ZIF‐8) is demonstrated. The synthetic strategy is based on the enhanced interaction between ZIF‐8 nanocrystals and metal nanoparticle surfaces covered by quaternary ammonium surfactants. High resolution electron microscopy and tomography confirm a complete core–shell morphology. Such a well‐defined morphology allowed us to study the transport of guest molecules through the ZIF‐8 porous shell by means of surface‐enhanced Raman scattering by the metal cores. The results demonstrate that even molecules larger than the ZIF‐8 aperture and pore size may be able to diffuse through the framework and reach the metal core.
Critical Perspectives on Disability Identity
Authors: Peña Edlyn Vallejo , Stapleton Lissa D. , Schaffer Lenore Malone
Published: June 2016

The authors examine the social construction of language, labels, and knowledge associated with disabilities, arguing in favor of critical and intersectional perspectives on disability identity.
Evaluating the Systems Engineering Problem Management Process for Industrial Manufacturing Problems
Authors: Perry Dennis A. , Olson Bill , Blessner Paul , Blackburn Timothy D.
Published: June 2016

Problems are ever‐present in nearly all engineered systems. A Systems Engineering Problem Management Process (SEPMP) has been proposed, and this research presents empirical evidence to support its validity. In order to evaluate the SEPMP, which uses a risk management style matrix to monitor problem timeliness and impact, it is necessary to determine the importance of communicating these components of the SEPMP model. A correlation and regression analysis is employed using existing empirical problem data and an analysis including communication of impact and timeliness components as independent variables. The dependent variable is the effectiveness of problem management, modeled as a measurement of the problem timeliness, implemented process improvements, training completed, and process delay as a result of the problem. Communication of timeliness and communication of impact are demonstrated to be significantly predictive of effective problem management. Finally, a plan for continued research is presented, including suggested future analyses to include additional empirical research and case studies of the implementation of a comprehensive problem management process, all of which may encourage acceptance of the SEPMP as a standard systems engineering tool.
Recent Advances in Self‐Oscillating Polymer Material Systems
Authors: Tamate Ryota , Mizutani Akimoto Aya , Yoshida Ryo
Published: June 2016

In 1996, we first reported self‐oscillating polymer gels exhibiting autonomous swelling‐deswelling oscillations driven by the Belousov‐Zhabotinsky reaction. In contrast to conventional stimuli‐responsive gels, the self‐oscillating gel can autonomously and periodically change its volume in a closed solution without any external stimuli. Since the first report, the novel concept of self‐oscillating gels has been expanded into various polymer and gel systems. Herein, we summarize recent advances in self‐oscillating polymers and gels.
English as a Second Language and World WarII: Possibilities for Language and Historical Learning
Authors: Stewart Mary Amanda , Walker Katie
Published: June 2016

Although, traditionally, the purpose of the social studies class in secondary schools is to teach content knowledge, this article argues that historical learning can be a powerful vehicle for English language development for late‐arrival English learners (ELs) in middle and high schools.ELs bring a wealth of life experiences, diverse perspectives, and global travel into the classroom that can nurture a dynamic learning environment when English as a second language (ESL) and social studies instruction are juxtaposed as content and language are taught simultaneously. This article details the learning results of a thematic unit on World WarIIfor late‐arrival refugeeELs in one high school using a formative design approach. Using the award‐winning historical fiction novelSylvia and Aki(Conkling, 2011) as well as other supporting texts, the teacher leveraged students' experiences to help them gain historical knowledge, literacy skills, and universal perspectives, all while acquiring English. Findings suggest that the social studies provide a rich space to naturally acquire a second language while simultaneously gaining a variety of content area knowledge. Specifically, World WarIImay provideESLteachers with a wealth of literary resources to engageELs in deep language and content learning.
Quality Matters: Content Literacy for English Language Learners
Authors: Zhang Wei
Published: June 2016

The Common Core State Standards (CCSS) require students to read and comprehend complex content texts. They specify three dimensions of a text that simultaneously contribute to text complexity across the curriculum: qualitative dimensions, quantitative dimensions, and reader and task considerations. In literacy instruction, recognizing and analyzing the qualitative dimension of a content text is the most challenging for teachers (Frey, Fisher, & Lapp, 2012). This article describes a TESOL course project to target the qualitative analysis of complex texts assigned to in‐service content teachers pursuing a TESOL endorsement. Building on the definition of text complexity specified in the CCSS and drawing on the text analysis tools of systemic functional linguistics, the project requires the teachers to conduct a comparative qualitative analysis of two quantitatively comparable content texts to enhance their own understanding of text complexity in order to design effective teaching strategies to support content literacy development of English language learners. An analysis of two literary texts is presented to illustrate the breadth and depth of this project, with suggestions of teaching strategies.
Closing the Gap: Student Attitudes Toward First Language Use in Monolingual EFL Classrooms
Authors: Neokleous Georgios
Published: June 2016

This article challenges the widely held assumption in monolingual English as a foreign language (EFL) settings that students prefer their teachers to rarely use their mother tongue (MT)—the language children initially learn in order to communicate. Through an examination of data derived from eight classrooms in four private language schools in Cyprus, the author identifies 16 speech acts performed by the students' exploitation of the first language (L1)—MT and L1 are used interchangeably—and unveils the students' overall stance toward MT classroom integration. The findings reveal that the participants did not perceive L1 usage in the EFL classroom as imposing a learning constraint, with the majority of them accentuating its benefits and admitting the impossibility of alienating it from the classroom. Although they opposed an L1 usage prohibition, the participants also stressed the necessity to improve the oral input of their second language—the language students learn in addition to their MT. Studies that explore the student voice, the article concludes, should form a productive starting point for important EFL research areas because they can foster awareness on issues that are considered important by learners but are undervalued by teachers (and vice versa).
Home Automation—A Fast ‐ Expanding Market
Authors: Khedekar Darshan Chandrashekhar , Truco Amelia Carrera , Oteyza Diego A. , Huertas Guillermo Florez
Published: June 2016

In recent years, a host of companies have tried to bridge the technology gap between home automation systems. This collective effort has led to the development of technologies that have triggered the beginning of device interoperability. A seamless ecosystem is being created that aims to improve comfort for dwellers, improve efficiency of homes, and, as an additional result, will create a massive market for home automation devices. Our research revealed that the home automation market has been growing at an enormous pace and additional integration of technologies would continue to stimulate demand even more, further diminishing costs and thereby reducing the exclusivity of the market by bringing them to the masses. © 2016 Wiley Periodicals, Inc.
Does menopausal transition really influence mental health? Findings from the prospective long‐term Zurich study
Authors: Rössler Wulf , Ajdacic‐Gross Vladeta , Riecher‐Rössler Anita , Angst Jules , Hengartner Michael P.
Published: June 2016

In the prospective long‐term Zurich study, we re‐examined the hypothesized association between mental health problems in women and the transition through menopausal stages. One hundred sixty‐eight women from a population‐based Swiss community cohort were prospectively followed up from age 21 to 50. At age 50, the occurrence of hot flushes/night sweats and sleep disturbances was significantly more frequent in peri‐ and post‐menopausal women. Irritability/nervousness was increased only in peri‐menopausal women, but that association was accounted for by neuroticism trait scores at age 30. Transitions to peri‐ or post‐menopause were not related to changes in either the prevalence rates of DSM major depressive episode or anxiety disorders, or the course of psychopathological syndromes as assessed by the Symptom Checklist 90 ‐ Revised. The null associations held when adjusting for duration of reproductive period or age at menopause. Preceding mental health problems between ages 21 and 41, increased neuroticism trait scores at age 30, and concurrent psychosocial distress were significantly related to mental health problems occurring between ages 41 and 50. Depending upon the cut‐off point that was chosen, the arbitrary dichotomization of a continuous depression outcome produced spurious associations with the menopausal transition. We conclude that mental health problems between ages 41 and 50 are probably not directly related to the menopausal transition, and that previously reported associations could be false positives due to inadequate dichotomizations, reporting bias, undisclosed multiple adjustments or overfitting.
Childhood adversities and psychosis: evidence, challenges, implications
Authors: Morgan Craig , Gayer‐Anderson Charlotte
Published: June 2016

There is a substantial body of research reporting evidence of associations between various forms of childhood adversity and psychosis, across the spectrum from experiences to disorder. This has been extended, more recently, to include studies of cumulative effects, of interactions with other factors, of specific effects, and of putative biological and psychological mechanisms. In this paper we evaluate this research and highlight the remaining methodological issues and gaps that temper, but do not dismiss, conclusions about the causal role of childhood adversity. We also consider the emerging work on cumulative, synergistic, and specific effects and on mechanisms; and discuss the broader implications of this line of research for our understanding of psychosis. We conclude that the current balance of evidence is that childhood adversities – particularly exposure to multiple adversities involving hostility and threat – do, in some people, contribute to the onset of psychotic experiences and psychotic disorders.
CRISPR/Cas9 genome editing throws descriptive 3‐D genome folding studies for a loop
Authors: Beagan Jonathan A. , Phillips‐Cremins Jennifer E.
Published: June 2016

CRISPR/Cas9 genome editing studies have recently shed new light into the causal link between the linear DNA sequence and 3‐D chromatin architecture. Here we describe current models for the folding of genomes into a nested hierarchy of higher‐order structures and discuss new insights into the organizing principles governing genome folding at each length scale. WIREs Syst Biol Med 2016, 8:286–299. doi: 10.1002/wsbm.1338

This article is categorized under:

Biological Mechanisms > Cell Fates

Developmental Biology > Developmental Processes in Health and Disease

Laboratory Methods and Technologies > Genetic/Genomic Methods
Bismuth(III) Complexes Based on Bis(triazol) Ligands: Effect of Fluorine Substitution on the Structure and Catalysis for the Polymerization of Glycolide
Authors: Gao Jian , Yuan Yu , Cui Ai‐Jun , Tian Feng , Chen Sheng‐Chun , He Ming‐Yang , Chen Qun
Published: June 2016

Two bismuth(III) complexes {[Bi(btx)0.5Cl4](Hbtx)}n (1) and [Bi2(Fbtx)Cl10](H2Fbtx)2(MeOH) (2) based on the nonfluorinated ligand 1,4‐bis[(1,2,4‐triazole‐1‐yl)methyl] benzene (btx) or the perfluorinated analogue 1,4‐bis[(1,2,4‐triazole‐1‐yl)methyl]‐2,3,5,6‐benzene (Fbtx) were synthesized and characterized. Single‐crystal X‐ray diffraction revealed that 1 is a coordination polymer consisting of an anionic one‐dimensional chain, whereas 2 shows a discrete ionic‐paired structure. Furthermore, 1 was found to be more active than 2 toward the bulk solvent‐free polymerization of glycolide, giving poly(glycolic acid) (PGA) with high molecular weights and moderate molecular weight distributions. The results indicated that the substituent effect plays an important role in controlling the structure and catalytic activity of such complexes.
Assembly of Two Coordination Polymers Based on the Flexible Carboxylate and N‐Donor Ligands with Polycatenane Characterization: Syntheses, Crystal Structures, and Luminescent Properties
Authors: Du Jie , Zou Guanglong , Guo Feng
Published: June 2016

The coordination polymers {[Zn3(bcp)2(bip)(OH)2]·2H2O}n (1) and {[Cd(bcp)(bpa)]·2H2O}n (2) [H2bcp = 1,3‐bis(4‐carboxy‐phenoxy) propane, bmp = 1,4‐bis(2‐methylimidazol‐3‐ium‐1‐yl) biphenyl, and bpa = bis(4‐pyridyl) amine] based on the flexible carboxylate and N‐donor ligands were synthesized and characterized. The structures were determined by single‐crystal X‐ray diffraction analysis and further characterized by elemental analysis, IR spectroscopy, and XPRD. Complex 1 displays a 2D→2D threefold interpenetrated network and complex 2 shows a 1D+1D→2D interpenetrated network. Furthermore, the luminescent properties of complexes 1 and 2 were investigated.
Predispositions to Lymphoma: A Practical Review for Genetic Counselors
Authors: Similuk Morgan , Rao V. Koneti , Churpek Jane , Lenardo Michael
Published: June 2016

This review provides a synopsis for genetic counselors of the major concepts of lymphoma predisposition: genomic instability, immune deficiency, inappropriate lymphoproliferation, and chronic antigen stimulation. We discuss syndromes typifying each of these mechanisms. Importantly, our review of the genetic counseling literature reveals sparse discussion of genetically‐based immune‐mediated lymphoma predisposition, which we address in depth here. We aim to increase awareness among genetic counselors and colleagues in oncology about familial susceptibility and facilitate critical thinking about lymphoma risk assessment. Clinical application of this knowledge is aided by recommendations for collection of personal and family history to guide risk assessment and testing. Lastly, we include a special discussion of genetic counseling issues including perceptions of the context, nature, and magnitude of lymphoma risk, as well as coping with awareness of susceptibility to lymphoma.
Medical students’ use of Facebook for educational purposes
Authors: Ali Anam
Published: June 2016

Medical students use Facebook to interact with one another both socially and educationally. This study investigates how medical students in a UK medical school use Facebook to support their learning. In particular, it identifies the nature of their educational activities, and details their experiences of using an educational Facebook group. Twenty-four medical students who self-identified as being Facebook users were invited to focus groups to attain a general overview of Facebook use within an educational context. A textual analysis was then conducted on a small group of intercalating medical students who used a self-created Facebook group to supplement their learning. Five of these students participated in semi-structured interviews. Six common themes were generated. These included ‘collaborative learning’, ‘strategic uses for the preparation for assessment’, ‘sharing experiences and providing support’, ‘creating and maintaining connections’, ‘personal planning and practical organization’ and ‘sharing and evaluating educational resources’. Evidence from this study shows that medical students are using Facebook informally to enhance their learning and undergraduate lives. Facebook has enabled students to create a supportive learning community amongst their peers. Medical educators wishing to capitalize on Facebook, as a platform for formal educational initiatives, should remain cautious of intruding on this peer online learning community.
Las capacidades de absorción del conocimiento como ventajas competitivas para la inserción de pymes en cadenas globales de valor
Authors: Olea-Miranda Jaime , Contreras Oscar F. , Barcelo-Valenzuela Mario
Published: June 2016

El propósito del estudio es identificar las capacidades de absorción del conocimiento como fuente de ventajas competitivas que potencializan en las pymes las posibilidades de integrarse a las cadenas globales de valor. Para ello se realizó una revisión del estado del arte que fundamenta la propuesta de un modelo basado en 2 enfoques teóricos: el de sistemas de innovación y el de cadenas globales de valor. La implementación se realizó en pymes del noroeste de México en los sectores de tecnologías de información y metalmecánica. Los resultados muestran que cuando las pymes locales son proveedoras de empresas transnacionales reciben transferencia de conocimientos que les permiten ingresar o mejorar su posición en las cadenas globales de valor.
Nonsurgical Resolution of a Bucket Handle Meniscal Tear: A Case Report
Authors: Urzen Jessica M. , Fullerton Bradley D.
Published: June 2016

A bucket handle meniscal tear (BHMT) often causes intermittent locking of the affected knee as the displaced fragment flips into the intercondylar notch. Surgical correction is usually required. Rare spontaneous healing of BHMTs has been described, primarily in young patients. This case report describes a 43‐year‐old man with magnetic resonance imaging–confirmed medial BHMT who received 3 treatments of platelet‐rich plasma injections in and around the meniscus within 7 months after the diagnosis of the tear. The patient reported resolution of pain with walking 8 months after the injury. Magnetic resonance imaging 10 months after the injury and arthroscopy 47 months after the injury showed complete resolution of the meniscal tear.

Level of Evidence

V
Effect of ring size on the side force over ogive-cylinder body at subsonic speed
Authors: Kumar P. , Prasad J.K.
Published: June 2016

Experiments and computations have been made to obtain the details of the flow field over a slender body at high angles of attack at a freestream velocity of 17 m/s corresponding to a Reynolds number of 2.9×104based on the base diameter. Experiments indicated that the existence of side force at higher angles of attack is mainly due to the presence of asymmetric vortices in the leeward side. A rectangular cross-section circular ring placed at an axial distance of 3.5 times the base diameter reduced the side force at all the angles of attack. Investigations were made to obtain the effect of the height of the ring at an angle-of-attack of 50° where the side force experienced is relatively large. A ring placed at a distance of 3.5 times the base diameter alters the initial vortices and hence helps in substantial reduction of the side force. Studies with rings of different heights indicate that a ring having a height of 3% of the local diameter reduced the side force at almost all the angles of attack for the present flow conditions and provided the least disturbance to the lift and drag of the body.
Helping Families Cope with the Severe Stress of Dravet Syndrome
Authors: Camfield Peter , Camfield Carol , Nolan Kathleen
Published: June 2016

A child with Dravet syndrome shakes family life to the core. Dravet syndrome usually has three phases: (1) up to 1-1½ years: with episodes of febrile status epilepticus but normal development; (2) age 1½ to ~6-10 years: with frequent seizures of varying types, developmental stagnation, behavioural and sleep problems; (3) after ~10 years: improvement in seizures, deteriorating gait, intellectual disability but some developmental gains. Complete seizure control is rare—simply prescribing medication is inadequate to help families. Based on structured interviews with 24 families and confirmed by more informal discussions with other families, we suggest strategies for coping with this catastrophe. A child with Dravet syndrome usually means that one parent cannot work—financial pressures should be anticipated. In Stage 1, the approach to status should include a written protocol. An indwelling catheter for rapid venous access may be helpful. In Stage 2, assistance finding qualified babysitters is required, and the extended family needs encouragement to help. Appropriate equipment, rescue medication and protocols should travel with the child. Siblings may benefit from a system of one parent “on call.” An internet support group provides an invaluable lifeline. In Stage 3, family isolation may be extreme—respite care and personal time for parents are important. Death from status, accidents and SUDEP (sudden unexplained death in epilepsy) occurs in 15%. Fear of SUDEP needs to be addressed. Moving from paediatric to adult care is frightening; an epilepsy transition clinic is useful. Attention to these realities may improve the quality of life for both child and family.
Treatment of Dravet Syndrome
Authors: Wirrell Elaine C.
Published: June 2016

Dravet syndrome is among the most challenging electroclinical syndromes. There is a high likelihood of recurrentstatus epilepticus; seizures are medically refractory; and patients have multiple co-morbidities, including intellectual disability, behaviour and sleep problems, and crouch gait. Additionally, they are at significant risk of sudden unexplained death. This review will focus predominantly on the prophylactic medical management of seizures, addressing both first-line therapies (valproate and clobazam) as well as second-line (stiripentol, topiramate, ketogenic diet) or later options (levetiracetam, bromides, vagus nerve stimulation). Sodium channel agents—including carbamazepine, oxcarbazepine, phenytoin and lamotrigine—should be avoided, as they typically exacerbate seizures. Several agents in development may show promise, specifically fenfluramine and cannabidiol, but they need further evaluation in randomized, controlled trials. In addition to prophylactic treatment, all patients need home-rescue medication and astatus epilepticusprotocol that can be carried out in their local hospital. Families must be counselled on non-pharmacologic strategies to reduce seizure risk, including avoidance of triggers that commonly induce seizures (including hyperthermia, flashing lights and patterns). In addition to addressing seizures, holistic care for a patient with Dravet syndrome must involve a multidisciplinary team that includes specialists in physical, occupational and speech therapy, neuropsychology, social work and physical medicine.
Surface manifestation of internal waves emitted by submerged localized stratified turbulence
Authors: Zhou Qi , Diamessis Peter J.
Published: June 2016

The internal waves (IWs) radiated by the turbulent wake of a sphere of diameter $D$ towed at speed $U$ are investigated using three-dimensional fully nonlinear simulations performed in a linearly stratified Boussinesq fluid with buoyancy frequency $N$. The study focuses on a broad range of wave characteristics in the far field of the turbulent wave source, specifically at the sea surface (as modelled by a free-slip rigid lid) where the IWs reflect. Six simulations are performed at Reynolds number $Re\equiv UD/{\it\nu}\in \{5\times 10^{3},10^{5}\}$ and Froude number $Fr\equiv 2U/(ND)\in \{4,16,64\}$, where ${\it\nu}$ is viscosity. The wave-emitting wake is located at a fixed distance of $9D$ below the surface. As the wake evolves for up to $O(300)$ units of buoyancy time scale $1/N$, IW characteristics, such as horizontal wavelength ${\it\lambda}_{H}$ and wave period $T$, are sampled at the sea surface via wavelet transforms of horizontal divergence signals. The statistics of amplitudes and orientations of IW-induced surface strains are also reported. The mean dimensionless observable wavelength $\overline{{\it\lambda}}_{H}/D$ at the sea surface decays in time as $(Nt)^{-1}$, which is due to the waves’ dispersion. This observation is in agreement with a linear propagation model that is independent of the wake $Re$ and $Fr$. This agreement further suggests that the most energetic waves impacting the surface originate from the early-time wake that is adjusting to buoyancy. The most energetic dimensionless wavelength $\hat{{\it\lambda}}_{H}/D$ is found to scale as $Fr^{1/3}$ and decrease with $Re$, which causes the arrival time (in $Nt$ units) of the strongest waves at the surface to scale as $Fr^{-1/3}$ and increase with $Re$. This wavelength $\hat{{\it\lambda}}_{H}$ is also found to correlate with the vertical Taylor scale of the wake turbulence. IW-driven phenomena at the surface that are of interest to an observer, such as the local enrichment of surfactant and the transport of ocean surface tracers, are also examined. The local enrichment ratio of surface scalar scales linearly with the steepness of IWs that reach the surface, and the ratio often exceeds a possible visibility threshold. The Lagrangian drifts of ocean tracers, which are linked to the nonlinear interaction between incident and reflecting IW packets, create a local divergence in lateral mass transport right above the wake centreline, an effect that intensifies strongly with increasing $Fr$. The findings of this study may serve as a platform to investigate the generation and surface manifestation of IWs radiated by other canonical submerged stratified turbulent flows.
Misdiagnosed neurosyphilis associated with prolonged psychosis
Authors: Faden Justin , O’Reardon John
Published: June 2016

Objective

After the prevalence of syphilis had reached historic lows, the Center for Disease Control devised a plan to eradicate syphilis in the United States. Since that decree there has been a dramatic rise in new cases. Psychosis is an ominous symptom of neurosyphilis.

Methods

We report a case of neurosyphilis that was misdiagnosed and staged incorrectly.

Results

Failure to diagnose neurosyphilis was associated with prolonged psychosis that has been refractory to antipsychotic treatment.

Conclusion

Psychiatrists should renew their vigilance for neurosyphilis in the setting of a positive screening test and psychosis.
Parasites, politics and public science: the promotion of biological control in Western Australia, 1900–1910
Authors: DEVESON EDWARD
Published: June 2016

Biological control of arthropods emerged as a scientific enterprise in the late nineteenth century and the orchard industry of California was an early centre of expertise. In 1900, as the Australian colonies prepared for federation, each had a government entomologist attached to its agriculture department. The hiring of George Compere from California by the Western Australian Department of Agriculture began a controversial chapter in the early history of biological control that was linked to a late, local popularization of acclimatization. Compere became known as the ‘travelling entomologist’ and for a decade brought ‘parasites’ of pest insects from overseas and released them in Perth. His antagonistic disciplinary rhetoric and inflated claims for the ‘parasite theory’ created conflict with his counterparts in the eastern states. The resulting inter-state entomological controversy was played out in the press, revealing the political use of science for institutional and even state identity. It is a story of transnational exchanges, chance discoveries and popular public science: popular because of the promise of a simple, natural solution to agricultural insect pests and because of the public nature of the disputes it generated between the experts. This microcosm contributes to the global historiography of acclimatization, biological control, scientific exposition and the professionalization of agricultural science.