bluuebunny/crossref_metadata_2025 huggingface dataset:
Smadditizin' Across the Years: Race and Class in the Work of Charles Mills
Authors: Sullivan Shannon
Published: January 2017

This article analyzes the changing relationship of race and class in the work of Charles Mills. Mills tells the story of his career by tracing an arc “from class to race,” which includes “an evolution of both focus and approach” that shifts the terms of his work “from red to black.” The article complicates this story by reading Mills's evolution through an intersectional lens. An intersectional approach to Mills's work allows a better appreciation (as he would agree) of how he does not move from class to race in the sense of abandoning the former for the latter, nor in the sense that race is utterly absent from his earlier work on class. Race and class are entangled with each other, and with gender and other axes of identity and power, in complex ways throughout his corpus. Mills's work remains red in certain respects—sometimes problematically from an intersectional perspective—even as it takes on black concerns and perspectives. On the flip side, as the end of the article asks, can Mills's work remain sufficiently red—that is, explicitly grapple with class concerns—as it tries to add some color to a whitewashed liberalism?
Supporting Mathematics Teachers’ Development through Higher Education
Authors: Prendergast Mark , Roche Joseph
Published: January 2017

Mathematics education, both nationally and internationally, is facing a number of challenges with significant on-going shifts in the structure, content, and core principles of mathematics curricula in countries around the world. For example, in Ireland there was an ambitious reform of the post-primary mathematics curricula in 2010 with further changes proposed in 2018. In light of these changes and concerns regarding ineffective teaching and a lack of continuous professional development, the National Council for Curriculum and Assessment (NCCA) has recommended that structures be put in place to facilitate practicing mathematics teachers to achieve postgraduate qualifications, ideally at Masters Level. To facilitate this recommendation, a new Mathematics Education strand of the Master in Education programme in Trinity College Dublin has been developed. This paper outlines the rationale for the new strand, as well as detailing its structure and content.
Embolisation supersélective bilatérale des artères vésicales pour contrôler une hématurie abondante d’un cancer de vessie métastatique
Authors: Saadi Ahmed , Bouzouita Abderrazak , Rebai Mohamed Hédi , Kerkeni Walid , Ayed Haroun , Cherif Mohamed , Rajhi Hatem , Ben Slama Riadh , Mnif Najla , Derouiche Amine , Chebil Mohamed
Published: January 2017

L’hématurie chez les patients présentant un cancer de la vessie localement avancé ou métastatique est une situation assez fréquente et qui pose souvent un problème de prise en charge. L’embolisation percutanée est une option mini-invasive pour gérer cette situation. Nous rapportons un cas d'un patient ayant un cancer métastatique de la vessie et qui a présenté avec une hématurie abondante et une anémie sévère. Après l'échec des résections endoscopiques et des "flushs" de radiothérapie à visée hémostatique et après le refus de la cystectomie par le patient, on a réalisé une embolisation supersélective et bilatérale des artères vésicales supérieures avec d'excellents résultats immédiats. La technique est sûre et efficace à court terme. L’évaluation de l’efficacité à long terme nécessite une étude plus approfondie.
Forecasting Volatility Stock Return: Evidence from the Nordic Stock Exchanges
Authors: Dritsakis Nikolaos , Savvas Georgios
Published: January 2017

The purpose of this study is to explore the volatility and secondary effects in the four Nordic stock exchanges of Norway: Oslo Bors Linked all-share index AXLT Denmark: OMX Copenhagen 20, Sweden: OMX Stockholm 30 and Finland: OMX Helsinki 25. Keeping in mind that there is an ARCH effect in the returns of the four stock exchanges, we move on to the evaluation to the evaluation of models ARCH (q), GARCH (p, q)  GARCH-M (p, q). Evaluating the parameters became possible through the use of the maximum likelihood method using the BHHH algorithm of (Berndt et al., 1974) and the three distributions (normal, t-Student, and the Generalized normal distribution GED). The results of this study indicate model ARMA(0,1)-GARCH-Μ(1,1) with t-student distribution as the appropriate one to describe the returns of the all Nordic stock exchanges except that of Sweden, where model ARMA(0,3)-GARCH-Μ(1,1) describes it best. Lastly, for forecasting the models ARMA(0,1)-GARCH-Μ(1,1) and ARMA(0,3)-GARCH-Μ(1,1) of the current stock exchanges we use both the dynamic and static process. The results of this study indicate that the static process forecasts better than the corresponding dynamic.
Main Worldwide Cultural Obstacles on Adopting International Financial Reporting Standards (IFRS)
Authors: Dowa Abulkasem , Elgammi Abdulmonem M. , Elhatab Abdesalam , Mutat Hassan A.
Published: January 2017

In recent times, the history of a country’s culture has become increasingly recognised as a crucial factor in its accounting methods. The globalization of the practice of economics has lead to homogenous international standards which are at the core of its development for practitioners, researchers and academics. This research considered some factors that might influence the adoption of International Financial Reporting Standards (IFRS) as cultural obstacles. This study investigates the religion, the language, technical skill and expertise as main cultural obstacles for the adoption of IFRS worldwide.Findings revealed the incompatibility of many IFRS with principles of Islamic religion, and also many non- English countries apply wrong implementation of IFRS because of translation issues of IFRS from English to their local languages. This study concluded that it is difficult to adopt IFRS in some countries and for some institutions because of the insufficient technical skill and experience of accountants and auditors to deal with those standards.
The Bank Sector Performance and Macroeconomics Environment: Empirical Evidence in Togo
Authors: Combey Adama , Togbenou Apelete
Published: January 2017

This article investigates short-run and long-run relationship between three main macroeconomic indicators (gross domestic product growth, real effective exchange rate, and inflation) and banking sector profitability (measured by return on assets and return on equity) in Togo, from 2006 to 2015, by using Pool Mean Group estimator. Results show that, in the short-run, banks’ return on assets and return on equity are not related to macroeconomic variables. But banks’ return on assets is determined positively by bank capital to assets ratio and bank size while banks’ return on equity is affected negatively by bank capital to assets ratio. However, in the long-run, real gross domestic product growth and real effective exchange rate affect negatively and statistically significant banks’ return on assets, while inflation rate has no effect. Concerning bank’s return on equity, in the long-run, results suggest that real gross domestic product growth, real effective exchange rate, and inflation affect negatively bank’s return on equity. These results imply that to stabilize bank profitability and make Togolese banking sector more resilient, policymakers and banking sector managers must, among others, try to improve real gross domestic product growth, real effective exchange rate, and inflation volatility anticipation.
Currency Substitution and Monetary Policy Effects: The Case of Latin American Countries
Authors: Kumamoto Hisao , Kumamoto Masao
Published: January 2017

In this study, we empirically investigate how currency substitution transmits foreign monetary policy shocks to domestic countries and evaluate how the central bank respond to real exchange rate movements in three inflation-targeting Latin American countries under currency substitution, namely Chile, Mexico and Peru, between 2000 and 2011. Our model is based on a small open economy dynamic stochastic general equilibrium model that incorporates currency substitution and incomplete financial markets, and we estimate it by using Bayesian estimation techniques. Our empirical results are as follows. First, the degree of currency substitution is higher in Mexico, while it is negligible in Chile and Peru, which reflects the slight differences in the parameter values capturing the preference for the domestic currency among these countries. Second, the estimated coefficients of the real exchange rate gap in the monetary policy rule are high, meaning that the central banks in these countries actively respond to real exchange rate movements to diminish real exchange rate volatility. Third, domestic monetary policy influences the domestic economy through the real interest rate channel. On the contrary, foreign monetary policy has a significant effect in Mexico, while it is insignificant in Chile and Peru. This finding suggests the potential instability of currency substitution in that slight changes in the parameter values capturing the preference for the domestic currency alter the degree of insulation from foreign monetary policy shocks.
What strategies are used by middle school students while solving mathematical tasks in a digital form
Authors: Czajkowska Monika
Published: January 2017

Mathematical problems are the source of mathematical and logical experience, in which student’s mind builds its mathematical competences. The sort of mathematical problems that are given to students and its form are not of no importance. Herein focus will be put on certain issues resulting from the usage of mathematical tasks presented to students in a digital form.
The author, based on her own study, characterizes the strategies that were used by the middle school students while solving interactive mathematical tasks. She states that no intervention from teacher’s side, thus letting students use a free method for solving tasks, does not positively influence the mathematical competences
to be acquired. With this, she questions the thesis that the middle school students grew up in the world of multimedia where the work with such mathematical task solving comes in a natural way. To the author’s way of thinking, it is necessary to work out a methodology that will be aiming at introducing students to solving mathematical tasks in a digital form.
Identifying NIST Impacts on Patenting: A Novel Data Set and Potential Uses
Authors: Anderson Gary W. , Breitzman Anthony
Published: January 2017

The National Institute of Standards and Technology’s (NIST’s) mission is to “promote U.S. innovation and industrial competitiveness.” To meet this mission, NIST scientists produce a great variety of scientific and technical outputs. This paper presents results from a novel effort to measure usage and impact of a more complete set of outputs, including patents, publications, research data, software, reference materials, and a variety of additional formal and informal scientific outputs. This effort captures a significantly broader set of scientific outputs than traditional citation analysis which typically examines patent-to-patent citations or more recently patent-to-(peer-reviewed) paper citations. This may be of significant importance to NIST as NIST scientists produce a wide variety of scientific and technical outputs beyond patents and papers. Our results indicate that metrics that solely rely on patents issued to NIST inventors understate NIST’s true impact on invention and do not capture usage of much of NIST’s scientific output by other inventors. Thus, identifying the magnitude and varied usage of different types of NIST outputs represents a significant improvement in NIST impact metrics. The results clearly indicate that different companies, industries and technologies rely on different types of NIST outputs. Therefore, reliance on a limited set of technology transfer tools by either researchers or policy makers creates a risk that NIST knowledge and capabilities will not be transferred to and adopted by businesses and other organizations. Finally, the data developed here suggest a number of new technology transfer metrics that promote shared technology transfer responsibilities and may focus attention on activities that increase the impact of current research without fundamentally altering the infrastructural character of this research.
NADPH oxidase-mediated redox signaling promotes oxidative stress resistance and longevity through memo-1 in C. elegans
Authors: Ewald Collin Yvès , Hourihan John M , Bland Monet S , Obieglo Carolin , Katic Iskra , Moronetti Mazzeo Lorenza E , Alcedo Joy , Blackwell T Keith , Hynes Nancy E
Published: January 2017

Transient increases in mitochondrially-derived reactive oxygen species (ROS) activate an adaptive stress response to promote longevity. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases produce ROS locally in response to various stimuli, and thereby regulate many cellular processes, but their role in aging remains unexplored. Here, we identified the C. elegans orthologue of mammalian mediator of ErbB2-driven cell motility, MEMO-1, as a protein that inhibits BLI-3/NADPH oxidase. MEMO-1 is complexed with RHO-1/RhoA/GTPase and loss of memo-1 results in an enhanced interaction of RHO-1 with BLI-3/NADPH oxidase, thereby stimulating ROS production that signal via p38 MAP kinase to the transcription factor SKN-1/NRF1,2,3 to promote stress resistance and longevity. Either loss of memo-1 or increasing BLI-3/NADPH oxidase activity by overexpression is sufficient to increase lifespan. Together, these findings demonstrate that NADPH oxidase-induced redox signaling initiates a transcriptional response that protects the cell and organism, and can promote both stress resistance and longevity.
Flow environment and matrix structure interact to determine spatial competition in Pseudomonas aeruginosa biofilms
Authors: Nadell Carey D , Ricaurte Deirdre , Yan Jing , Drescher Knut , Bassler Bonnie L
Published: January 2017

Bacteria often live in biofilms, which are microbial communities surrounded by a secreted extracellular matrix. Here, we demonstrate that hydrodynamic flow and matrix organization interact to shape competitive dynamics in Pseudomonas aeruginosa biofilms. Irrespective of initial frequency, in competition with matrix mutants, wild-type cells always increase in relative abundance in planar microfluidic devices under simple flow regimes. By contrast, in microenvironments with complex, irregular flow profiles – which are common in natural environments – wild-type matrix-producing and isogenic non-producing strains can coexist. This result stems from local obstruction of flow by wild-type matrix producers, which generates regions of near-zero shear that allow matrix mutants to locally accumulate. Our findings connect the evolutionary stability of matrix production with the hydrodynamics and spatial structure of the surrounding environment, providing a potential explanation for the variation in biofilm matrix secretion observed among bacteria in natural environments.
Dynamic Changes in Liver Stiffness Measured by Transient Elastography Predict Clinical Outcomes Among Patients With Chronic Hepatitis B
Authors: Zeng Jianyong , Cai Shaohang , Liu Jiajun , Xue Xiulan , Wu Xiaolu , Zheng Caixia
Published: January 2017

Objectives

We aimed to evaluate the validity of transient elastography in monitoring the antiviral outcomes in patients with chronic hepatitis B.

Methods

This study included 108 patients treated with nucleos(t)ide analogues and 67 patients treated with interferon (IFN). Liver biopsies were evaluated by the METAVIR score. Transient elastography was performed initially at baseline, 48 weeks, and 96 weeks. Liver tissue was obtained before and after 96 weeks of treatment. The area under the receiver operating characteristic curve was used to examine the diagnostic value of transient elastography in predicting and monitoring outcomes of antiviral treatment.

Results

The liver stiffness value correlated well with the baseline alanine aminotransferase level (r = 0.33; P < .001) and was significantly different among various stages of liver fibrosis (P < .001). In the nucleos(t)ide analogue group, the mean pretreatment and posttreatment liver stiffness values ± SD were 8.7 ± 3.1 and 5.9 ± 1.6 kPa, respectively (P < .001), and they were 9.2 ± 3.7 and 7.2 ± 1.9 kPa (P < .001) in the IFN group. Although the liver stiffness values at baseline between the groups were similar (P = .45), they were 5.9 ± 1.6 kPa in the nucleos(t)ide analogue group and 7.2 ± 1.9 kPa in the IFN group after 48 weeks of treatment (P < .001). With the decreased magnitude liver stiffness for predicting the improvement in liver fibrosis, the area under the receiver operating characteristic curve was 0.68 (P = .029). When the decreased magnitude of liver stiffness was 4.1 kPa or higher, the sensitivity and specificity for predicting a histologic response were 88.2% and 50.0%.

Conclusions

Our findings suggest that transient elastography is an effective measurement tool for diagnosing and monitoring the histologic response in patients with chronic hepatitis B during antiviral treatment and can help avoid multiple liver biopsies.
Interphalangeal Joint Sonography of Symptomatic Hand Osteoarthritis: Clinical and Functional Correlation
Authors: Spolidoro Paschoal Natalia de Oliva , Natour Jamil , Machado Flavia S. , Alcântara Veiga de Oliveira Hilda , Vilar Furtado Rita Nely
Published: January 2017

Objectives

To assess the correlation between inflammatory sonographic findings (grayscale synovial hypertrophy and power Doppler) and clinical and functional assessments in hand osteoarthritis (symptomatic interphalangeal joints) and to correlate the intraobserver and interobserver reliability of these findings.

Methods

A prospective double‐blind study of 60 interphalangeal joints was conducted. The joints were assessed 6 times per year by clinician and sonographer observers.

Results

A total of 720 measurement recesses were included (360 palmar and 360 dorsal). Small correlations and a few associations were found. Proximal interphalangeal joint quantitative measurements of the dorsal recess showed a statistical correlation with joint swelling (P = .043) and pulp‐to‐pulp pinch strength (P = .043); in the palmar recess, statistical correlations were seen for joint swelling (P = .007), the Australian/Canadian (AUSCAN) Function Index (P = .044), and grip and finger strength (P = .037, .003, .019, and .017). In dorsal semiquantitative assessments, there were associations between sonographic findings and joint swelling (P = .010) and pinch strength (P = .027, .003, and .014); in the palmar recess, we found associations with the AUSCAN Index (P = .048) and grip and finger strength (P = .031, .006, and 0.041). No correlations or associations were found in distal interphalangeal joints. Power Doppler signals were found in only 1.7% of the sample, precluding statistical analysis. Excluding palmar semiquantitative assessments in distal interphalangeal joints (P = .623), sonographic findings were reliable (intraclass correlation coefficients, 0.474–0.857; κ = 0.390–0.673).

Conclusions

Joint swelling, grip and pinch strength, and the AUSCAN Index were weakly correlated and associated with sonographic findings in proximal interphalangeal joints. Intraobserver and interobserver sonographic assessments were reliable.
Measurement of Blood Flow in an Intracranial Artery Bypass From the Internal Maxillary Artery by Intraoperative Duplex Sonography
Authors: Yu Zaitao , Shi Xiang'en , Brohi Shams Raza , Qian Hai , Liu Fangjun , Yang Yang
Published: January 2017

This study explored the hemodynamic characteristics of a subcranial–intracranial bypass from the internal maxillary artery by measuring blood flow on intraoperative duplex sonography. The hemodynamic parameters of the internal maxillary artery (n = 20), radial artery (n = 20), internal maxillary artery–middle cerebral artery bypass (n = 42), and internal maxillary artery–posterior cerebral artery bypass (n = 9) were measured by intraoperative duplex sonography. There was no significant difference in the internal diameters of the internal maxillary and radial arteries (mean ± SD, 2.51 ± 0.34 versus 2.56 ± 0.22 mm; P = .648). The mean radial artery graft length for subcranial–intracranial bypasses was 88.5 ± 12.78 mm (95% confidence interval [CI], 80.8–90.2 mm). Internal maxillary artery–middle cerebral artery bypasses required a shorter radial artery graft than internal maxillary artery–posterior cerebral artery bypasses (77.8 ± 2.47 versus 104.8 ± 4.77 mm; P = .001). The mean flow volumes were 85.3 ± 18.5 mL/min (95% CI, 76.6–93.9 mL/min) for the internal maxillary artery, 72.6 ± 26.4 mL/min (95% CI, 64.3–80.9 mL/min) for internal maxillary artery–middle cerebral artery bypasses, and 45.4 ± 6.7 mL/min (95% CI, 40.7–50.0 mL/min) for internal maxillary artery–posterior cerebral artery bypasses. All grafts were opened after the success of the salvage procedures had been established, and the early patency rates (1 month after the operation) were 95% for internal maxillary artery–middle cerebral artery bypasses and 100% the internal maxillary artery–posterior cerebral artery bypasses. Measurement of blood flow by intraoperative sonography can be helpful in decision making and predicting graft patency and success after neurosurgical bypass procedures.
Multiparametric Sonography of Hematologic Malignancies of the Testis: Grayscale, Color Doppler, and Contrast‐Enhanced Ultrasound and Strain Elastographic Appearances With Histologic Correlation
Authors: Kachramanoglou Carolina , Rafailidis Vasileios , Philippidou Marianna , Bertolotto Michele , Huang Dean Y. , Deganello Annamaria , Sellars Maria E. , Sidhu Paul S.
Published: January 2017

Primary testicular lymphoma is rare and appears with nonspecific findings on grayscale and color Doppler sonography. We present 8 patients further examined with contrast‐enhanced sonography, strain elastography, and histologic analysis after orchiectomy. Seven of 8 patients had a diagnosis of large B‐cell lymphoma, and 1 of 8 had a diagnosis of granulocytic sarcoma, with solitary lesions (2 of 8), multiple lesions (3 of 8), or entire testicular involvement (3 of 8). Lesions appeared hypoechoic (7 of 8) or isoechoic (1 of 8), all with increased vascularity on color Doppler sonography and a nonbranching linear pattern of intratumoral vessels (7 of 8). Contrast‐enhanced ultrasound (CEUS) confirmed this pattern and showed increased enhancement in all lesions. On strain elastography, all lesions were hard, with an elasticity score of greater than 4. Multiparametric sonography of testicular lymphoma identifies increased vascularity on color Doppler and contrast‐enhanced ultrasound and increased lesion stiffness on strain elastography.
Sonoanatomy and Pathology of the Posterior Band of the Gluteus Medius Tendon
Authors: Hoffman Douglas F. , Smith Jay
Published: January 2017

Greater trochanteric pain syndrome is a common clinical entity that most often results from disorders of the gluteus medius tendon. There are two distinct bands of the gluteus medius tendon, and abnormalities may affect the anterior or posterior band in isolation or simultaneously. Although abnormalities of the anterior band are more common, awareness and sonographic detection of posterior band abnormalities is essential to guide treatment in the setting of greater trochanteric pain syndrome.
Rab8A regulates insulin‐stimulated GLUT4 translocation in C2C12 myoblasts
Authors: Li Hanbing , Ou Liting , Fan Jiannan , Xiao Mei , Kuang Cuifang , Liu Xu , Sun Yonghong , Xu Yingke
Published: January 2017

Rab proteins are important regulators of GLUT4 trafficking in muscle and adipose cells. It is still unclear which Rabs are involved in insulin‐stimulated GLUT4 translocation in C2C12 myoblasts. In this study, we detect the colocalization of Rab8A with GLUT4 and the presence of Rab8A at vesicle exocytic sites by TIRFM imaging. Overexpression of dominant‐negative Rab8A (T22N) diminishes insulin‐stimulated GLUT4 translocation, while constitutively active Rab8A (Q67L) augments it. In addition, knockdown of Rab8A inhibits insulin‐stimulated GLUT4 translocation, which is rescued by replenishment of RNAi‐resistant Rab8A. Together, these results indicate an indispensable role for Rab8A in insulin‐regulated GLUT4 trafficking in C2C12 cells.
Equatorial electrojet responses to intense solar flares under geomagnetic disturbance time electric fields
Authors: Abdu M. A. , Nogueira P. A. B. , Souza J. R. , Batista I. S. , Dutra S. L. G. , Sobral J. H. A.
Published: January 2017

Large enhancement in the equatorial electrojet (EEJ) current can occur due to sudden increase in the E layer density arising from solar flare associated ionizing radiations, as also from background electric fields modified by magnetospheric disturbances when present before or during a solar flare. We investigate the EEJ responses at widely separated longitudes during two X‐class flares that occurred at different activity phases surrounding the magnetic super storm sequences of 28–29 October 2003. During the 28 October flare we observed intense reverse electrojet under strong westward electric field in the sunrise sector over Jicamarca. Sources of westward disturbance electric fields driving large EEJ current are identified for the first time. Model calculations on the E layer density, with and without flare, and comparison of the results between Jicamarca and Sao Luis suggested enhanced westward electric field due to the flare occurring close to sunrise (over Jicamarca). During the flare on 29 October, which occurred during a rapid AE recovery, a strong overshielding electric field of westward polarity over Jicamarca delayed an expected EEJ eastward growth due to flare‐induced ionization enhancement in the afternoon. This EEJ response yielded a measure of the overshielding decay time determined by the storm time Region 2 field‐aligned current. This paper will present a detailed analysis of the EEJ responses during the two flares, including a quantitative evaluation of the flare‐induced electron density enhancements and identification of electric field sources that played dominant roles in the large westward EEJ at the sunrise sector over Jicamarca.
Inmate Altercations
Authors: Davis Jaya
Published: January 2017

The goal of prison staff is to ensure the safety and security of those within prison walls. Violence jeopardizes this main function, and inmate altercations or inmate on inmate fights are the primary source of violence within prisons. Inmate altercations are just one offense in the larger group of prison disciplinary infractions and overall prison violence. Of all disciplinary infractions that occur in prison, fights between inmates are the most common. Although inmate altercations have decreased in recent decades, they continue to exact psychological, physical, and fiscal costs.
Projective Empowerment: Co‐creative Sustainable Design Processes
Authors: Krietemeyer Bess
Published: January 2017

The human body's perception of ambient energy flows in the built environment is a complex yet important consideration in designing high performance architectural systems, buildings and cities. Bess Krietemeyer, Assistant Professor at the School of Architecture at Syracuse University and Head of the Interactive Design and Visualization Lab (IDVL) at the Syracuse Center of Excellence, explores how interactive hybrid‐reality platforms for experiencing and analysing bioclimatic flows in architectural design are empowering designers and end users to engage in collaborative design processes from diverse viewpoints and across spatial scales.
Check‐In: Foursquare and the Rich Annotated Topology of Citizen‐Generated Hyperlocal Data
Authors: Luis de Vincente José
Published: January 2017

Over the last few years, a new resource has emerged for studying the evolution of specific cities. That resource is urban annotation: the attachment of comments to places so that they can later be accessed by others in that same location via smartphone. The city guide app Foursquare is the prime example of this. Barcelona‐based curator and cultural researcher José Luis de Vicente examines the app from its origins to the types of data it generates, considering its implications and its surprisingly accurate predictive potentials.
Advanced Raman Spectroscopy Using Nanofocusing of Light
Authors: Nuytten Thomas , Bogdanowicz Janusz , Hantschel Thomas , Schulze Andreas , Favia Paola , Bender Hugo , De Wolf Ingrid , Vandervorst Wilfried
Published: January 2017

Raman spectroscopy is uniquely sensitive to crucial material properties like stress and composition, but is inherently diffraction‐limited, impeding its application potential in nanostructured devices. Under correct polarization conditions, the Raman response from a periodic array of fins is dramatically enhanced inside the semiconductor material, re‐enabling fast and non‐destructive optical characterization of deep‐subwavelength semiconductor patterns. In this paper, it is shown that the effect is not limited to the material system where it was first observed, and results of nanofocused Raman spectroscopy in a variety of semiconductor materials are presented. The authors illustrate and discuss how the universality of the enhancement creates a unique potential for non‐invasive and rapid stress and composition measurements at the nanoscale.
Anomalous Channel‐Length Dependence in Nanofluidic Osmotic Energy Conversion
Authors: Cao Liuxuan , Xiao Feilong , Feng Yaping , Zhu Weiwei , Geng Wenxiao , Yang Jinlei , Zhang Xiaopeng , Li Ning , Guo Wei , Jiang Lei
Published: January 2017

Recent advances in materials science and nanotechnology have lead to considerable interest in constructing ion‐channel‐mimetic nanofluidic systems for energy conversion and storage. The conventional viewpoint suggests that to gain high electrical energy, the longitudinal dimension of the nanochannels (L) should be reduced so as to bring down the resistance for ion transport and provide high ionic flux. Here, counterintuitive channel‐length dependence is described in nanofluidic osmotic power generation. For short nanochannels (with length L < 400 nm), the converted electric power persistently decreases with the decreasing channel length, showing an anomalous, non‐Ohmic response. The combined thermodynamic analysis and numerical simulation prove that the excessively short channel length impairs the charge selectivity of the nanofluidic channels and induces strong ion concentration polarization. These two factors eventually undermine the osmotic power generation and its energy conversion efficiency. Therefore, the optimal channel length should be between 400 and 1000 nm in order to maximize the electric power, while balancing the efficiency. These findings reveal the importance of a long‐overlooked element, the channel length, in nanofluidic energy conversion and provide guidance to the design of high‐performance nanofluidic energy devices.
Degradability and Clearance of Silicon, Organosilica, Silsesquioxane, Silica Mixed Oxide, and Mesoporous Silica Nanoparticles
Authors: Croissant Jonas G. , Fatieiev Yevhen , Khashab Niveen M.
Published: January 2017

The biorelated degradability and clearance of siliceous nanomaterials have been questioned worldwide, since they are crucial prerequisites for the successful translation in clinics. Typically, the degradability and biocompatibility of mesoporous silica nanoparticles (MSNs) have been an ongoing discussion in research circles. The reason for such a concern is that approved pharmaceutical products must not accumulate in the human body, to prevent severe and unpredictable side‐effects. Here, the biorelated degradability and clearance of silicon and silica nanoparticles (NPs) are comprehensively summarized. The influence of the size, morphology, surface area, pore size, and surface functional groups, to name a few, on the degradability of silicon and silica NPs is described. The noncovalent organic doping of silica and the covalent incorporation of either hydrolytically stable or redox‐ and enzymatically cleavable silsesquioxanes is then described for organosilica, bridged silsesquioxane (BS), and periodic mesoporous organosilica (PMO) NPs. Inorganically doped silica particles such as calcium‐, iron‐, manganese‐, and zirconium‐doped NPs, also have radically different hydrolytic stabilities. To conclude, the degradability and clearance timelines of various siliceous nanomaterials are compared and it is highlighted that researchers can select a specific nanomaterial in this large family according to the targeted applications and the required clearance kinetics.
Copper‐Silver Dual Catalyzed Decyanative C–Se Cross‐Coupling
Authors: Mukherjee Nirmalya , Kundu Debasish , Ranu Brindaban C.
Published: January 2017

Traditionally, a metal‐catalyzed cross‐coupling reaction is governed by displacement of leaving groups such as halogens, tosylates, etc. by different nucleophiles leading to the formation of carbon‐carbon and carbon‐heteroatom bonds. Besides displacement of traditional leaving groups in coupling reactions decyanative cross‐coupling has also received current attention. The objective of this work is to develop a decyanative cross‐coupling through metal‐assisted nucleophilic displacement, which is less explored so far. Thus, a decyanative cross‐coupling of aryl selenocyanate with aryl‐/alkylacetylenes, boronic acids and silanes has been accomplished by a copper‐assisted nucleophilic displacement reaction for an easy access to a series of diaryl, aryl alkyl, aryl vinyl and aryl alkynyl selenides. The best yield of product was obtained using 5 mol% of Cu(OAc)2, Ag2CO3 (20 mol%) and Cs2CO3 (1 equiv.) at 100 °C for 8 h in N‐methylpyrrolidinone (NMP). The advantages of simple operation, high yields and general applicability make this procedure more attractive. A mechanistic pathway has been proposed. Silver plays a key role in the decyanation process. A plausible mechanistic pathway of this decyanative carbon‐selenium cross‐coupling has been proposed based on UV, EPR, HR‐MS and IR analytical data along with results obtained from control experiments.

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Defect Engineering in Multinary Earth‐Abundant Chalcogenide Photovoltaic Materials
Authors: Shin Donghyeop , Saparov Bayrammurad , Mitzi David B.
Published: January 2017

Application of zinc‐blende‐related chalcogenide absorbers such as CdTe and Cu(In,Ga)Se2 (CIGSe) has enabled remarkable advancement in laboratory‐ and commercial‐scale thin‐film photovoltaic performance; however concerns remain regarding the toxicity (CdTe) and scarcity (CIGSe/CdTe) of the constituent elements. Recently, kesterite‐based Cu2ZnSn(S,Se)4 (CZTSSe) materials have emerged as attractive non‐toxic and earth‐abundant absorber candidates. Despite the similarities between CZTSSe and CIGSe/CdTe, the record power conversion efficiency of CZTSSe solar cells (12.6%) remains significantly lower than that of CIGSe (22.6%) and CdTe (22.1%) devices, with the performance gap primarily being attributed to cationic disordering and associated band tailing. To capture the promise of kesterite‐like materials as prospective “drop‐in” earth‐abundant replacements for closely‐related CIGSe, current research has focused on several key directions to control disorder, including: (i) examination of the interaction between processing conditions and atomic site disorder, (ii) isoelectronic cation substitution to introduce ionic size mismatch, and (iii) structural diversification beyond the zinc‐blende‐type coordination environment. In this review, recent efforts targeting accurate identification and engineering of anti‐site disorder in kesterite‐based CZTSSe are considered. Lessons learned from CZTSSe are applied to other complex chalcogenide semiconductors, in an effort to develop promising pathways to avoid anti‐site disordering and associated band tailing in future high‐performance earth‐abundant photovoltaic technologies.
Non‐malignant respiratory disease among workers in industries using styrene—A review of the evidence
Authors: Nett Randall J. , Cox‐Ganser Jean M. , Hubbs Ann F. , Ruder Avima M. , Cummings Kristin J. , Huang Yuh‐Chin T. , Kreiss Kathleen
Published: January 2017

Background

Asthma and obliterative bronchiolitis (OB) cases have occurred among styrene‐exposed workers. We aimed to investigate styrene as a risk factor for non‐malignant respiratory disease (NMRD).

Methods

From a literature review, we identified case reports and assessed cross‐sectional and mortality studies for strength of evidence of positive association (i.e., strong, intermediate, suggestive, none) between styrene exposure and NMRD‐related morbidity and mortality.

Results

We analyzed 55 articles and two unpublished case reports. Ten OB cases and eight asthma cases were identified. Six (75%) asthma cases had abnormal styrene inhalation challenges. Thirteen (87%) of 15 cross‐sectional studies and 12 (50%) of 24 mortality studies provided at least suggestive evidence that styrene was associated with NMRD‐related morbidity or mortality. Six (66%) of nine mortality studies assessing chronic obstructive pulmonary disease‐related mortality indicated excess mortality.

Conclusions

Available evidence suggests styrene exposure is a potential risk factor for NMRD. Additional studies of styrene‐exposed workers are warranted. Am. J. Ind. Med. 60:163–180, 2017. © 2016 Wiley Periodicals, Inc.
Total Syntheses of Two bis‐Allylic‐Deuterated DHA Analogues
Authors: Rosell Mélissa , Villa Maxime , Durand Thierry , Galano Jean‐Marie , Vercauteren Joseph , Crauste Céline
Published: January 2017

The deuteration of polyunsaturated fatty acids (PUFAs) at their bis‐allylic positions is known to limit harmful lipid peroxidation, which leads to the damage of cell membranes. Therefore, to impede toxic lipid peroxidation in retina tissue, we have designed and synthesized two deuterated analogues of docosahexaenoic acid (DHA; C22:6, n‐3), which is the main lipid constituent of retina membranes. To avoid its oxidative degradation into toxic carboxyethylpyrrole (CEP) adducts, whilst preserving enzymatic metabolization into a healthy neuroprotectine derivative (NPD1), deuterium was incorporated at specific 6‐ and 6,9‐bis‐allylic positions. A convergent synthetic strategy, based on a Wittig olefination, was developed to obtain both deuterated DHA species. Common aldehyde intermediates were synthesized from another PUFA, eicosapentaenoic acid (EPA; C20:5, n‐3). Deuterium atoms were introduced through either the reduction of an ester with a deuterated reagent or a nucleophilic reaction with deuterated paraformaldehyde.
Rare‐region effects and dynamics near the many‐body localization transition
Authors: Agarwal Kartiek , Altman Ehud , Demler Eugene , Gopalakrishnan Sarang , Huse David A. , Knap Michael
Published: January 2017

The low‐frequency response of systems near the many‐body localization phase transition, on either side of the transition, is dominated by contributions from rare regions that are locally “in the other phase”, i.e., rare localized regions in a system that is typically thermal, or rare thermal regions in a system that is typically localized. Rare localized regions affect the properties of the thermal phase, especially in one dimension, by acting as bottlenecks for transport and the growth of entanglement, whereas rare thermal regions in the localized phase act as local “baths” and dominate the low‐frequency response of the MBL phase. We review recent progress in understanding these rare‐region effects, and discuss some of the open questions associated with them: in particular, whether and in what circumstances a single rare thermal region can destabilize the many‐body localized phase.

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An Unusually Delocalized Mixed‐Valence State of a Cyanidometal‐Bridged Compound Induced by Thermal Electron Transfer
Authors: Ma Xiao , Lin Chen‐Sheng , Zhu Xiao‐Quan , Hu Sheng‐Min , Sheng Tian‐Lu , Wu Xin‐Tao
Published: January 2017

The heterometallic complexes trans‐[Cp(dppe)FeNCRu(o‐bpy)CNFe(dppe)Cp][PF6]n (1[PF6]n, n=2, 3, 4; o‐bpy=1,2‐bis(2,2′‐bipyridyl‐6‐yl)ethane, dppe=1,2‐bis(diphenylphosphino)ethane, Cp=1,3‐cyclopentadiene) in three distinct states have been synthesized and fully characterized. 13+[PF6]3 and 14+[PF6]4 are the one‐ and two‐electron oxidation products of 12+[PF6]2, respectively. The investigated results suggest that 1[PF6]3 is a Class II mixed valence compound. 1[PF6]4 after a thermal treatment at 400 K shows an unusually delocalized mixed valence state of [FeIII‐NC‐RuIII‐CN‐FeII], which is induced by electron transfer from the central RuII to the terminal FeIII in 1[PF6]4, which was confirmed by IR spectroscopy, magnetic data, and EPR and Mössbauer spectroscopy.
Preparation and properties of poly(ε‐caprolactone) self‐reinforced composites based on fibers/matrix structure
Authors: Han Lei , Xu Hong , Sui Xiaofeng , Zhang Linping , Zhong Yi , Mao Zhiping
Published: January 2017

Self‐reinforced poly(ε‐caprolactone) (PCL) composites were prepared from bi‐component PCL yarns composed of PCL drawn fibers and PCL matrix by a combined process of yarns winding and hot‐pressing. Series of PCL polymers with different melting points were synthesized and used as matrix. PCL melt‐spun fibers were subject to different draw ratios and functioned as reinforcement. During the process of hot‐pressing, the matrix with low melting points melted and bonded the unmelted drawn fibers together creating self‐reinforced composites, the morphologies of which were examined by scanning electron microscope. Tensile testing of the composites was performed along the longitudinal and transverse directions separately. The longitudinal tensile test results showed that the Young's modulus and strength at break of the self‐reinforced composites were 59% and 250% higher than that of pure PCL. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44673.
Strategic escapes: Negotiating motivations of personal growth and instrumental benefits in the decision to study abroad
Authors: Trower Holly , Lehmann Wolfgang
Published: January 2017

Studying abroad is one way in which university students can develop personal capital and distinguish themselves in an increasingly congested graduate labour market. Data show that studying abroad indeed provides employment benefits, with evidence pointing to even greater positive effects for students from low socio‐economic status backgrounds. Focusing on a group of Canadian students about to embark on a study exchange, we find no evidence that career‐instrumental reasons played a role in participants’ decisions to study abroad. Rather, they sought personal growth and escape from the everyday frustrations of being an undergraduate student. We argue, however, that these motivations nonetheless have to be understood as strategic, since going on a study exchange abroad allows students to escape temporarily, while ‘staying in the game’ of becoming credentialed at home. We discuss the role of socio‐economic status, as well as the policy implications of these findings.
Latitude as a co‐driver of human gut microbial diversity?
Authors: Dikongué Emma , Ségurel Laure
Published: January 2017

The human gut microbial diversity has been reported to be lower in industrialized populations as compared to non‐industrialized ones. Since it is also reduced in individuals with some metabolic and inflammatory diseases as compared to healthy ones, this “loss” of diversity in industrialized populations is currently considered to be a public health issue. However, little is known on the mechanisms that are causing this pattern. Is it due to differences in diet, sanitation, medication, host genetics, and/or other unidentified factors? In this review, we propose that part of this decrease in diversity is driven by latitude, as all studied industrialized countries are in higher latitudes than non‐industrialized ones, and latitude is known to correlate with species diversity. Reanalyzing available data, we find that part of the gut microbial diversity is significantly correlated with latitude, which might therefore exacerbate the effect of lifestyle. Intriguingly, the observation of a higher diversity in industrialized countries has not been replicated in other human microbiomes.
The Buffering Effect of Parental Mediation in the Relationship between Adolescents' Cyberbullying Victimisation and Adjustment Difficulties
Authors: Wright Michelle F.
Published: January 2017

As cyberbullying research advances, many researchers have focused on identifying factors that might reduce the negative consequences associated with cyberbullying victimisation. One prominent factor receiving attention is the role of parental mediation in digital technology use, and how such mediation reduces the risk of cybervictimisation. Parents utilise different mediation strategies (i.e. restrictive, co‐viewing, instructive), which could potentially contribute to differential patterns in the relationships between cyberbullying victimisation and the associated psychosocial adjustment difficulties (i.e. depression, loneliness, anxiety). The present study investigated this proposal among 568 US (53% female) adolescents in the eighth grade (age ranging from 13–15 years), utilising a longitudinal design. Cyberbullying victimisation was related positively to restrictive mediation and Time 2 depression, anxiety and loneliness, while such associations were negative for co‐viewing mediation and instructive mediation. High levels of co‐viewing mediation and instructive mediation made the relationship of cyberbullying victimisation to Time 2 (1 year later) depression more negative. The results of this study are discussed in terms of the supportive role of parents in adolescents' digital technology use. Copyright © 2017 John Wiley & Sons, Ltd.

‘Identifying factors that might reduce the negative consequences associated with cyberbullying victimisation’

Key Practitioner Messages

Cyberbullying victimisation is linked positively to depression, anxiety and loneliness as well as restrictive mediation.

Cyberbullying victimisation is related negatively to co‐viewing mediation and instructive mediation.

Co‐viewing mediation and instructive mediation buffer against adolescents' depression and anxiety resulting from cyberbullying victimisation.

‘Co‐viewing mediation and instructive mediation buffer against adolescents' depression and anxiety resulting from cyberbullying victimisation’
Chemodiversity of Epicuticular n‐Alkanes and Morphological Traits of Natural Populations of Satureja subspicata Bartl. ex Vis. along Dinaric Alps – Ecological and Taxonomic Aspects
Authors: Dodoš Tanja , Rajčević Nemanja , Tešević Vele , Marin Petar D.
Published: January 2017

Morphological characters and the composition of epicuticular leaf n‐alkanes of two Satureja subspicata Bartl. ex Vis. subspecies (subsp. liburnica Šilić and subsp. subspicata) from nine natural populations along Dinaric Alps range were studied. Morphological characters were chosen based on Šilićʼs subspecies separation. Seventeen n‐alkane homologues (C19 – C35) were identified using gas chromatography/mass spectrometry (GC/MS) and GC/flame ionisation detector (FID). The most abundant n‐alkane in all populations was n‐nonacosane (C29), followed by n‐hentriacontane (C31), with the exception of Divača population where these two alkanes were co‐dominant. Diversity and variability of n‐alkane patterns and morphological characters and their relation to different geographic and bioclimatic parameters, including exposure, were analysed by several statistical multivariate methods (PCA, HCA, Discriminant Analysis, Mantel test). These tests showed clear separation of subsp. liburnica from subsp. subspicata, even though population Velebit showed separation from other subsp. liburnica populations based on phytochemical characters. Mantel test showed high correlation with geographical distribution in both investigated data sets. High correlation between morphological and phytochemical characters was also established. However, exposure can influence n‐alkane profile, suggesting precaution while taking samples from natural habitats.