bluuebunny/crossref_metadata_2025 huggingface dataset:
Fast in-situ photoluminescence analysis for a recombination parameterization of the fast BO defect component in silicon
Authors: Niewelt T. , Mägdefessel S. , Schubert M. C.
Published: August 2016

Light-induced degradation due to BO defects in silicon consists of a fast initial decay within a few seconds followed by a slower decay within hours to days. Determination of injection dependent charge carrier lifetime curves during the initial decay is challenging due to this short timeframe. We have developed a suitable measurement technique based on in situ photoluminescence measurements and present results of our studies of the fast degradation component. The temporal evolution of the recombination activity is studied and assessed by means of a two-level Shockley-Read-Hall statistics. A quadratic dependence of the fast defect activation on the hole concentration during illumination is demonstrated. We suggest a new parameterization of the recombination activity introduced by fast-formed BO defects featuring energy levels 0.34 eV below the conduction band and 0.31 eV above the valence band. The capture asymmetry ratio determined for the donor level of 18.1 is significantly smaller than previous parameterizations in literature suggest.
A statistical study of gyro-averaging effects in a reduced model of drift-wave transport
Authors: da Fonseca J. D. , del-Castillo-Negrete D. , Sokolov I. M. , Caldas I. L.
Published: August 2016

A statistical study of finite Larmor radius (FLR) effects on transport driven by electrostatic drift-waves is presented. The study is based on a reduced discrete Hamiltonian dynamical system known as the gyro-averaged standard map (GSM). In this system, FLR effects are incorporated through the gyro-averaging of a simplified weak-turbulence model of electrostatic fluctuations. Formally, the GSM is a modified version of the standard map in which the perturbation amplitude, K0, becomes K0J0(ρ̂), where J0 is the zeroth-order Bessel function and ρ̂ is the Larmor radius. Assuming a Maxwellian probability density function (pdf) for ρ̂, we compute analytically and numerically the pdf and the cumulative distribution function of the effective drift-wave perturbation amplitude K0J0(ρ̂). Using these results, we compute the probability of loss of confinement (i.e., global chaos), Pc, and the probability of trapping in the main drift-wave resonance, Pt. It is shown that Pc provides an upper bound for the escape rate, and that Pt provides a good estimate of the particle trapping rate. The analytical results are compared with direct numerical Monte-Carlo simulations of particle transport.
Locally adaptive method to define coordination shell
Authors: Higham Jonathan , Henchman Richard H.
Published: August 2016

An algorithm is presented to define a particle’s coordination shell for any collection of particles. It requires only the particles’ positions and no pre-existing knowledge or parameters beyond those already in the force field. A particle’s shell is taken to be all particles that are not blocked by any other particle and not further away than a blocked particle. Because blocking is based on two distances and an angle for triplets of particles, it is called the relative angular distance (RAD) algorithm. RAD is applied to Lennard-Jones particles in molecular dynamics simulations of crystalline, liquid, and gaseous phases at various temperatures and densities. RAD coordination shells agree well with those from a cut-off in the radial distribution function for the crystals and liquids and are slightly higher for the gas.
Effect of interface roughness on exchange coupling in polycrystalline Co/CoO bilayer structure: An in-situ investigation
Authors: Kumar Dileep , Singh Sadhana , Gupta Ajay
Published: August 2016

The effect of interface roughness on exchange-bias (EB) properties of polycrystalline Co/CoO bilayer structure has been studied in-situ. Isothermal annealing of a 135 Å thick Co layer under the partial pressure of pure oxygen at 573 K results in the formation of a 35 Å thick CoO layer, the surface roughness of which increases with the increasing annealing time. Bilayers were characterized in-situ using magneto-optic Kerr effect, reflection high energy electron diffraction, and x-ray reflectivity for their magnetic and structural properties during each stage of bilayer growth. Combined analysis revealed that the increase in the roughness from 7 ±0.5 Å to 13 ±Å causes the exchange bias field (HEB) to decrease from 171 Oe to 81 Oe, whereas coercivity (HC) increases up to 616 Oe. In contrast to some earlier studies on polycrystalline films, where HEB increased with roughness due to the increase in the uncompensated spins at ferromagnetic-antiferromagnetic (AFM) layer interface, in the present case, dependence of HEB and HC on the roughness is attributed to the disorder at the interface of AFM layer, which leads to a decrease in HEB due to weakening of the effective spin coupling at the interface. Present in-situ experiments make it possible to study the variations in EB properties with the interface roughness in a single sample, and thus avoiding the possibility of the sample to sample variation in the morphological properties along with the change in the interface roughness.
Sequential control of step-bunching during graphene growth on SiC (0001)
Authors: Bao Jianfeng , Yasui Osamu , Norimatsu Wataru , Matsuda Keita , Kusunoki Michiko
Published: August 2016

We have investigated the relation between the step-bunching and graphene growth phenomena on an SiC substrate. We found that only a minimum amount of step-bunching occurred during the graphene growth process with a high heating rate. On the other hand, a large amount of step-bunching occurred using a slow heating process. These results indicated that we can control the degree of step-bunching during graphene growth by controlling the heating rate. We also found that graphene coverage suppressed step bunching, which is an effective methodology not only in the graphene technology but also in the SiC-based power electronics.
Strain management of AlGaN-based distributed Bragg reflectors with GaN interlayer grown by metalorganic chemical vapor deposition
Authors: Liu Yuh-Shiuan , Wang Shuo , Xie Hongen , Kao Tsung-Ting , Mehta Karan , Jia Xiao Jia , Shen Shyh-Chiang , Yoder P. Douglas , Ponce Fernando A. , Detchprohm Theeradetch , Dupuis Russell D.
Published: August 2016

We report the crack-free growth of a 45-pair Al0.30Ga0.70N/Al0.04Ga0.96N distributed Bragg reflector (DBR) on 2 in. diameter AlN/sapphire template by metalorganic chemical vapor deposition. To mitigate the cracking issue originating from the tensile strain of Al0.30Ga0.70N on GaN, an AlN template was employed in this work. On the other hand, strong compressive strain experienced by Al0.04Ga0.96N favors 3D island growth, which is undesired. We found that inserting an 11 nm thick GaN interlayer upon the completion of AlN template layer properly managed the strain such that the Al0.30Ga0.70N/Al0.04Ga0.96N DBR was able to be grown with an atomically smooth surface morphology. Smooth surfaces and sharp interfaces were observed throughout the structure using high-angle annular dark-field imaging in the STEM. The 45-pair AlGaN-based DBR provided a peak reflectivity of 95.4% at λ = 368 nm with a bandwidth of 15 nm.
Tailoring magnetostriction sign of ferromagnetic composite by increasing magnetic field strength
Authors: Gou Junming , Liu Xiaolian , Wu Kaiyun , Wang Yue , Hu Shanshan , Zhao Hui , Xiao Andong , Ma Tianyu , Yan Mi
Published: August 2016

The unitary deformation of single-phase ferromagnets by a magnetic field, i.e., either positive or negative linear magnetostriction, allows only monotonous control. Here we report a proof-of-principle ferromagnetic composite Fe73Ga27, for which the magnetostriction sign changes from positive to negative by increasing the magnetic field strength. Based on the transformation from body-centered-cubic (BCC) to face-centered-cubic (FCC) phases in this binary system, Fe73Ga27 composite is prepared by aging the BCC averaged precursor for 3 days at 803 K. Magnetic measurements indicate that the BCC phase exhibits smaller magnetocrystalline anisotropy constant than the FCC phase. The offset effect between BCC and FCC phases produces positive net magnetostriction at low magnetic fields but negative net magnetostriction at high magnetic fields. By tuning the field strength, such composites can mediate compressive and tensile strains to other functional materials, e.g., piezoelectric material or optic-fibers, which is beneficial to design multifunctional devices.
Note: Autocollimation with ultra-high resolution and stability using telephoto objective together with optical enlargement and beam drift compensation
Authors: Zhu Fan , Tan Xinran , Tan Jiubin , Fan Zhigang
Published: August 2016

An autocollimation (AC) setup with ultra-high resolution and stability for micro-angle measurement is presented. The telephoto objective, which is characterized in long focal length at a compact structure size, and the optical enlargement unit, which can magnify the image displacement to improve its measurement resolution and accuracy, are used to obtain an ultra-high measurement resolution of the AC. The common-path beam drift compensation is used to suppress the drift of measurement results, which is evident in the high-resolution AC, thus to obtain a high measurement stability. Experimental results indicate that an effective resolution of better than 0.0005 arc sec (2.42 nrad) over a measurement range of ±30 arc sec and a 2-h stability of 0.0061 arc sec (29.57 nrad) can be achieved.
Computation of Electron Delocalization for Extended Cyclic Conjugated Molecules
Authors: Song Suhwan , Han Minwoo , Sim Eunji
Published: August 2016

Cyclic conjugated molecules have relatively planar conformations due to overlap of adjacent π-orbitals of delocalized electrons and which is strongly correlated with the degree of electron delocalization. We first demonstrate the quantitative relationship between structural heterogeneity and two structural parameters: out-of-plane distances of atoms and torsional angles between neighbouring aromatic moieties. The molecular characteristic-dependent trend of planarity is presented in terms of these two parameters for the number of unit moieties, type and distribution of linkers, and substituting alkyl groups. The method presented may provide a simple yet systematic guide for determining the degree of delocalization of cyclic conjugated molecules.
Mineralogy of volcanically derived alluvial soils at Moshi, Tanzania
Authors: Taylor T. S. , Hughes J. C. , Titshall L. W.
Published: August 2016

Despite intensive commercial agriculture in the rift zone of Tanzania, mineralogical studies on the soils influenced by volcanic parent materials are scarce. A mineralogical investigation of the soils and two buried ash layers from an irrigated sugar estate was undertaken using X-ray diffraction, transmission electron microscopy and measurements of extractable iron, aluminium and silicon and the specific surface area (SSA) of the clay fraction. The dominant mineral in the sand and silt fractions was sanidine. The clay fractions contained mainly high-defect kaolin, illite and K-feldspar, with small amounts of calcite, talc and gibbsite in some samples. Electron microscopy revealed the presence of tubular and spheroidal halloysite and <0.5µm kaolinite crystals, as well as nanocrystalline material, probably allophane, and volcanic glass. The amounts of ferrihydrite (0.34–1.84%) and allophane (0.52–6.84%) were low in the soils but higher in the buried ash layers. The surface areas of the clay fractions were high (up to 145m2g–1) and it was calculated that 5% allophane constituted 22% of the total SSA. Although all soils were dominated by halloysite and small kaolinite particles, it is likely that the small amounts of allophane with high SSA has a strong effect on their physical and chemical properties.
Wettability control on multiphase flow in patterned microfluidics
Authors: Zhao Benzhong , MacMinn Christopher W. , Juanes Ruben
Published: August 2016

Significance

The simultaneous flow of multiple fluid phases through a porous solid occurs in many natural and industrial processes—for example, rainwater infiltrates into soil by displacing air, and carbon dioxide is stored in deep saline aquifers by displacing brine. It has been known for decades that wetting—the affinity of the solid to one of the fluids—can have a strong impact on the flow, but the microscale physics and macroscopic consequences remain poorly understood. Here, we study this in detail by systematically varying the wetting properties of a microfluidic porous medium. Our high-resolution images reveal the fundamental control of wetting on multiphase flow, elucidate the inherently 3D pore-scale mechanisms, and help explain the striking macroscopic displacement patterns that emerge.
Novel allele-dependent role for APOE in controlling the rate of synapse pruning by astrocytes
Authors: Chung Won-Suk , Verghese Philip B. , Chakraborty Chandrani , Joung Julia , Hyman Bradley T. , Ulrich Jason D. , Holtzman David M. , Barres Ben A.
Published: August 2016

Significance

Susceptibility to Alzheimer’s disease (AD) is strongly controlled by apolipoprotein E (
APOE
) genotype. The
E4
allele greatly increases risk whereas the
E2
allele decreases risk, but it is not known how the
APOE
allele controls AD risk. In this paper, we report a novel role for APOE by showing that APOE2 enhances and APOE4 decreases the rate of synapse pruning and turnover in the brain by astrocytes. We also show that
APOE
alleles control the rate of accumulation of the complement C1q protein, which we hypothesize, reflects senescent synapse accumulation during normal brain aging and vulnerability of the aging brain to neurodegenerative diseases such as AD.
Influence of a Minimum-Length Limit Regulation on Wild Brown Trout: an Example of Recruitment and Growth Overfishing
Authors: Sánchez-Hernández Javier , Shaw Stephanie L. , Cobo Fernando , Allen Mike S.
Published: August 2016

The relative abundance of the largest size-classes of individuals within a fish population has an important influence on recruitment success. Fishing regulations with a basis in size (e.g., minimum-length limits) can directly impact the abundance of these larger individuals and thus potentially influence recruitment. We analyzed whether recruitment of exploited native Brown Trout Salmo trutta populations was affected via the extraction of large individuals (>220 mm, i.e., minimum-length limit). The study was replicated temporally (2007–2009) and spatially across seven recreational fishing sections (four exploited and three catch-and-release sections) within the River Tormes located in central Spain. Catch-and-release sections were used as reference points to compare with exploited sections. We tested the hypothesis that minimum-length limit regulations would adversely affect fish recruitment through fishing-induced mortality of large individuals. Spawning stock (measured as fish >220 mm) and young-of-the-year abundances were estimated using multiple-pass depletion methods. We modeled the relationship between spawning stock and subsequent recruitment using a nonparametric approach (generalized additive models) to fit the best stock–recruit relationship. Additionally, von Bertalanffy growth and yield-per-recruit models were generated to evaluate the potential for growth and recruitment overfishing. The restrictive length limits used to regulate harvest in the study area limited both recruitment and adult abundance. The present study provides evidence that the use of minimum-length limit regulations in the management of recreational fisheries has the potential to adversely affect the species’ recruitment. Such adverse impacts could be occurring via both recruitment overfishing and growth overfishing, exemplifying that the removal of the larger size-classes of individuals through recreational fishing could have important consequences for recruitment. Management actions should be directed to protect large individuals (e.g., via harvest slots) rather than promote their removal, thereby reducing the chances of overfishing.

Received November 25, 2015; accepted April 18, 2016Published online August 24, 2016
Predicting Complex Syntactic Structure in Real Time: Processing of Negative Sentences in Russian
Authors: Kazanina Nina
Published: August 2016

In Russian negative sentences the verb's direct object may appear either in the accusative case, which is licensed by the verb (as is common cross-linguistically), or in the genitive case, which is licensed by the negation (Russian-specific “genitive-of-negation” phenomenon). Such sentences were used to investigate whether case marking is employed for anticipating syntactic structure, and whether lexical heads other than the verb can be predicted on the basis of a case-marked noun phrase. Experiment 1, a completion task, confirmed that genitive-of-negation is part of Russian speakers’ active grammatical repertoire. In Experiments 2 and 3, the genitive/accusative case manipulation on the preverbal object led to shorter reading times at the negation and verb in the genitive versus accusative condition. Furthermore, Experiment 3 manipulated linear order of the direct object and the negated verb in order to distinguish whether the abovementioned facilitatory effect was predictive or integrative in nature, and concluded that the parser actively predicts a verb and (otherwise optional) negation on the basis of a preceding genitive-marked object. Similarly to a head-final language, case-marking information on preverbal noun phrases (NPs) is used by the parser to enable incremental structure building in a free-word-order language such as Russian.
The Ccz1-Mon1-Rab7 module and Rab5 control distinct steps of autophagy
Authors: Hegedűs Krisztina , Takáts Szabolcs , Boda Attila , Jipa András , Nagy Péter , Varga Kata , Kovács Attila L. , Juhász Gábor
Published: August 2016

The small GTPase Rab5 promotes recruitment of the Ccz1-Mon1 guanosine exchange complex to endosomes to activate Rab7, which facilitates endosome maturation and fusion with lysosomes. How these factors function during autophagy is incompletely understood. Here we show that autophagosomes accumulate due to impaired fusion with lysosomes upon loss of the Ccz1-Mon1-Rab7 module in starved Drosophila fat cells. In contrast, autophagosomes generated in Rab5-null mutant cells normally fuse with lysosomes during the starvation response. Consistent with that, Rab5 is dispensable for the Ccz1-Mon1–dependent recruitment of Rab7 to PI3P-positive autophagosomes, which are generated by the action of the Atg14-containing Vps34 PI3 kinase complex. Finally, we find that Rab5 is required for proper lysosomal function. Thus the Ccz1-Mon1-Rab7 module is required for autophagosome-lysosome fusion, whereas Rab5 loss interferes with a later step of autophagy: the breakdown of autophagic cargo within lysosomes.
Spatial regulation of astral microtubule dynamics by Kif18B in PtK cells
Authors: Walczak Claire E. , Zong Hailing , Jain Sachin , Stout Jane R.
Published: August 2016

The spatial and temporal control of microtubule dynamics is fundamentally important for proper spindle assembly and chromosome segregation. This is achieved, in part, by the multitude of proteins that bind to and regulate spindle microtubules, including kinesin superfamily members, which act as microtubule-destabilizing enzymes. These fall into two general classes: the kinesin-13 proteins, which directly depolymerize microtubules, and the kinesin-8 proteins, which are plus end–directed motors that either destabilize microtubules or cap the microtubule plus ends. Here we analyze the contribution of a PtK kinesin-8 protein, Kif18B, in the control of mitotic microtubule dynamics. Knockdown of Kif18B causes defects in spindle microtubule organization and a dramatic increase in astral microtubules. Kif18B-knockdown cells had defects in chromosome alignment, but there were no defects in chromosome segregation. The long astral microtubules that occur in the absence of Kif18B are limited in length by the cell cortex. Using EB1 tracking, we show that Kif18B activity is spatially controlled, as loss of Kif18B has the most dramatic effect on the lifetimes of astral microtubules that extend toward the cell cortex. Together our studies provide new insight into how diverse kinesins contribute to spatial microtubule organization in the spindle.
PhenomeScape: a cytoscape app to identify differentially regulated sub-networks using known disease associations
Authors: Soul Jamie , Dunn Sara L. , Hardingham Tim E. , Boot-Handford Ray P. , Schwartz Jean-Marc
Published: August 2016

Summary: PhenomeScape is a Cytoscape app which provides easy access to the PhenomeExpress algorithm to interpret gene expression data. PhenomeExpress integrates protein interaction networks with known phenotype to gene associations to find active sub-networks enriched in differentially expressed genes. It also incorporates cross-species phenotypes and associations to include results from animal models of disease. With expression data imported into PhenomeScape, the user can quickly generate and visualise interactive sub-networks. PhenomeScape thus enables researchers to use prior knowledge of a disease to identify differentially regulated sub-networks and to generate an overview of altered biologically processes specific to that disease.

Availability and Implementation: Freely available for download at https://github.com/soulj/PhenomeScape

Contact:  jamie.soul@postgrad.manchester.ac.uk or jean-marc.schwartz@manchester.ac.uk
KScons: a Bayesian approach for protein residue contact prediction using the knob-socket model of protein tertiary structure
Authors: Li Qiwei , Dahl David B. , Vannucci Marina , Joo Hyun , Tsai Jerry W.
Published: August 2016

Motivation: By simplifying the many-bodied complexity of residue packing into patterns of simple pairwise secondary structure interactions between a single knob residue with a three-residue socket, the knob-socket construct allows a more direct incorporation of structural information into the prediction of residue contacts. By modeling the preferences between the amino acid composition of a socket and knob, we undertake an investigation of the knob-socket construct’s ability to improve the prediction of residue contacts. The statistical model considers three priors and two posterior estimations to better understand how the input data affects predictions. This produces six implementations of KScons that are tested on three sets: PSICOV, CASP10 and CASP11. We compare against the current leading contact prediction methods.

Results: The results demonstrate the usefulness as well as the limits of knob-socket based structural modeling of protein contacts. The construct is able to extract good predictions from known structural homologs, while its performance degrades when no homologs exist. Among our six implementations, KScons MST-MP (which uses the multiple structure alignment prior and marginal posterior incorporating structural homolog information) performs the best in all three prediction sets. An analysis of recall and precision finds that KScons MST-MP improves accuracy not only by improving identification of true positives, but also by decreasing the number of false positives. Over the CASP10 and CASP11 sets, KScons MST-MP performs better than the leading methods using only evolutionary coupling data, but not quite as well as the supervised learning methods of MetaPSICOV and CoinDCA-NN that incorporate a large set of structural features.

Contact:  qiwei.li@rice.edu

Supplementary information:  Supplementary data are available at Bioinformatics online.
An analysis of the operative capacity of non-governmental organizations in the Southern region of Punjab Province, Pakistan
Authors: Jabeen Sadia , Yasmin Nighat
Published: August 2016

This study explores the operative capacity of non-governmental organizations (NGOs) in the Southern region of Punjab Province, Pakistan. Data from all functional NGOs registered with the Social Welfare and the Bait-ul-Maal Department, Punjab under the provisions of the Voluntary Social Welfare Agencies (Registration and Control) Ordinance, 1961 were collected. A questionnaire based on basic information about NGOs, namely about membership, elections, services offered and opportunities for capacity building, was used for data collection. The results of the study identify education, health, and vocational and technical training as the three major areas of activity for NGOs in the Southern region. The study also found that NGOs do not have an adequate democratic process for elections. Women’s participation is less than men’s in general and in particular regarding membership of executive bodies. The core areas where gaps in capacity building were found are in governance and leadership, financial and human resource management, record maintenance and reporting. On the basis of the findings of this study, it is suggested that NGOs should extend their areas of operation and field of services, and that the democratic process could be ensured by concerned departments through proper monitoring and surveillance.
Le Vieux de la Montagne, ou les vertus du contre-exemple: Le
Roman des Sept Sages
,
Barlaam et Josaphat
, Le
Décaméron
Authors: Uhlig Marion
Published: August 2016

À l’occasion d’une réflexion sur les adaptations littéraires médiévales de l’histoire du Vieux de la Montagne, l’article interroge le potentiel de vérité de la littérature, et notamment les capacités de la fiction à séduire et à subvertir. Le propos est nourri par l’analyse de trois fables qui résonnent avec cette trame légendaire et sont enchâssées dans trois ‘récits à tiroirs’ d’importance majeure: ‘L’Exemple du Haschischin’ dans le
Roman des sept sages
(version M:
L’Ystoire de la male marastre
, fin du treizième ou début du quatorzième siècle); ‘La Séduction’ dans
Barlaam et Josaphat
(rédaction du treizième siècle); et la nouvelle des ‘Oies du père Philippe’ dans le
Décaméron
de Boccace, dans l’adaptation française du quinzième siècle réalisée par Laurent de Premierfait. L’enjeu est double: il s’agit en premier lieu de mettre en valeur la quête de vérité qui habite la littérature exemplaire ou plutôt, en l’occurrence, contre-exemplaire; de manière subsidiaire, on souhaite révéler le lien, jusqu’ici insu, qui relie les fables de
Barlaam et Josaphat
et du
Décaméron
à celle des
Sept sages
et, à travers elle, au mythe du Vieux de la Montagne.
Renoir’s Automaton, Vigo’s Puppet: Automatism and Movement in
La Règle du jeu
and
L’Atalante
Authors: ffrench Patrick
Published: August 2016

Jean Renoir’s 1939 film
La Règle du jeu
incorporates several automata as indexes of the alienated status of the class it depicts, including the orchestrion that the main protagonist Robert de La Chesnaye unveils as the ultimate piece in his collection. This focus on machines is as much an expression of the film’s eighteenth-century philosophical and aesthetic references as it is a revelation of an anachronistic relation to the machine as such, and to the form of movement it embodies. In a key scene the display of the orchestrion falters, revealing a deathly repetition that the moribund pseudo-aristocracy cannot accommodate. The opposition drawn by Lacan between automaton and
tuchē
in his eleventh seminar, as well as Deleuze’s intimation of the ‘crack’ in the filmic crystal that Renoir’s cinema deploys, illuminate this moment as an event of pure repetition. In contrast, Jean Vigo’s 1934 film
L’Atalante
depicts a human–machine relation that allows for forms of connection and innovation of a more organic nature. Across these representations of automatism and movement, the cinema of the 1930s explores patterns of alienation and of historicity, for which the theses of Walter Benjamin provide a powerful interpretative framework.
If it does not kill them, it makes them stronger: collisional evolution of star clusters with tidal shocks
Authors: Gieles Mark , Renaud Florent
Published: August 2016

The radii of young (≲100 Myr) star clusters correlate only weakly with their masses. This shallow relation has been used to argue that impulsive tidal perturbations, or ‘shocks’, by passing giant molecular clouds (GMCs) preferentially disrupt low-mass clusters. We show that this mass–radius relation is in fact the result of the combined effect of two-body relaxation and repeated tidal shocks. Clusters in a broad range of environments including those like the solar neighbourhood evolve towards a typical radius of a few parsecs, as observed, independent of the initial radius. This equilibrium mass–radius relation is the result of a competition between expansion by relaxation and shrinking due to shocks. Interactions with GMCs are more disruptive for low-mass clusters, which helps to evolve the globular cluster mass function (GCMF). However, the properties of the interstellar medium in high-redshift galaxies required to establish a universal GCMF shape are more extreme than previously derived, challenging the idea that all GCs formed with the same power-law mass function.
Positive and Negative Thinking in Tinnitus: Factor Structure of the Tinnitus Cognitions Questionnaire
Authors: Handscomb Lucy E. , Hall Deborah A. , Shorter Gillian W. , Hoare Derek J.
Published: August 2016

Objectives:

Researchers and clinicians consider thinking to be important in the development and maintenance of tinnitus distress, and altering thoughts or thinking style is an object of many forms of psychological therapy for tinnitus. Those working with people with tinnitus require a reliable, psychometrically robust means of measuring both positive and negative thinking related to it. The Tinnitus Cognitions Questionnaire (TCQ) was designed as such a measure and its authors showed it to be reliable, with good psychometric properties. However, no research teams have yet carried out independent validation. This study aimed to use the TCQ to investigate thinking amongst members of the general population with both bothersome and nonbothersome tinnitus and also to verify its factor structure.

Design:

Three hundred forty-two members of the public with tinnitus completed the TCQ online or on paper. They also rated their tinnitus on a scale as “not a problem,” “a small problem,” “a moderate problem,” “a big problem,” or a “very big problem.” The authors tested the original factor structure of the TCQ using confirmatory factor analysis and then calculated the mean scores for each item, comparing mean total scores across “problem categories” for the full questionnaire and for the positive and negative subscales.

Results:

The original two-factor structure of the TCQ was a good fit to the data when the correlation between positive and negative factors was fixed at zero (root mean square error of approximation = 0.064, 90% confidence interval = 0.058 to 0.070). Items pertaining to wishing the tinnitus would go away and despairing that it would ever get better had the highest mean scores. The mean total score for the “no problem” group (M = 31.17, SD = 16.03) was not significantly different from the mean total score for the “small problem” group (M = 34.00, SD = 12.44,p= 0.99). Differences between mean scores for all other groups were statistically significant. For the negative subscale, differences were statistically significant between all problem categories. For the positive subscale, the differences between mean scores were only statistically significant for the “no problem” group (M = 28.40, SD = 17.11) compared with the “moderate problem” group (M = 18.55, SD = 8.64,p= 0.02) and for the “moderate problem” group compared with the “very big problem” group (M = 26.79, SD = 11.66,p= 0.002). Positive and negative factors were uncorrelated (ρ= −0.03.)

Conclusions:

The TCQ is a valid measure of positive and negative thinking in tinnitus, and the authors recommend its use in research and therapeutic settings. Negative thinking appears to be associated with more problematic tinnitus, but positive thinking is not associated with unproblematic tinnitus, suggesting that reducing negative thinking may be more important than teaching positive thinking in therapy.
Aberrant immune response with consequent vascular and connective tissue remodeling – causal to scleroderma and associated syndromes such as Raynaud phenomenon and other fibrosing syndromes?
Authors: Durmus Nedim , Park Sung-Hyun , Reibman Joan , Grunig Gabriele
Published: August 2016

Purpose of review

Scleroderma and other autoimmune-induced connective tissue diseases are characterized by dysfunctions in the immune system, connective tissue and the vasculature. We are focusing on systemic sclerosis (SSc)-associated pulmonary hypertension, which remains a leading cause of death with only a 50–60% of 2-year survival rate.

Recent findings

Much research and translational efforts have been directed at understanding the immune response that causes SSc and the networked interactions with the connective tissue and the vasculature. One of the unexpected findings was that in some cases the pathogenic immune response in SSc resembles the immune response to helminth parasites. During coevolution, means of communication were developed which protect the host from over-colonization with parasites and which protect the parasite from excessive host responses. One explanation for the geographically clustered occurrence of SSc is that environmental exposures combined with genetic predisposition turn on triggers of molecular and cellular modules that were once initiated by parasites.

Future research is needed to further understand the parasite-derived signals that dampen the host response. Therapeutic helminth infection or treatment with parasite-derived response modifiers could be promising new management tools for autoimmune connective tissue diseases.
Myopathy in scleroderma and in other connective tissue diseases
Authors: Paik Julie J.
Published: August 2016

Purpose of review

This review discusses the most updated literature of myopathy in scleroderma and other connective tissue diseases.

Recent findings

In the past year, studies have demonstrated that myopathy in scleroderma is associated with poor outcomes such as disability and mortality. In addition, muscle histopathology in scleroderma continues to reveal that it is a heterogeneous entity, and that necrosis and acute neurogenic atrophy may be a more prevalent histopathologic feature in muscle biopsies than previously reported. In other connective tissue diseases such as SLE, the onset of overlap myositis typically does not occur simultaneously as it does in scleroderma or rheumatoid arthritis.

Myopathy in scleroderma is heterogeneous and given that it is associated with poor outcomes, it is imperative that optimal diagnostic strategies and therapies including a classification criterion be developed. In other connective tissue diseases, such as rheumatoid arthritis and systemic lupus erythematosus, myopathy is even more poorly defined and requires more robust studies to clarify both the clinical features and muscle histopathology in this group.
The role of myokines in muscle health and disease
Authors: Lightfoot Adam P. , Cooper Robert G.
Published: August 2016

Purpose of review

This article updates on the concept that muscle-derived cytokines (myokines) play important roles in muscle health and disease.

Recent findings

Interleukin-6 (IL-6) is released from normal skeletal muscle in response to exercise, mediating both anti-inflammatory responses and metabolic adaptations, actions contradictory to the prevailing view that IL-6 is a proinflammatory cytokine that is inducing and propagating disease. The anti-inflammatory effects of IL-6 result from its trans-membrane signalling capability, via membrane-bound receptors, whereas its proinflammatory effects result instead from signalling via the soluble IL-6 receptor and gp130. IL-15 is elevated following exercise, promoting muscle fibre hypertrophy in some circumstances, while inducing fibre apoptosis in others. This functional divergence appears because of variations in expression of IL-15 receptor isoforms. Decorin, a recently described myokine, is also elevated following exercise in normal muscle, and promotes muscle fibre hypertrophy by competitively binding to, and thus inhibiting, myostatin, a negative regulator of muscle protein synthesis. Exercise-induced myostatin downregulation thus promotes muscle fibre growth, prompting recent trials of a biological myostatin inhibitor in inclusion body myositis.

Myokines appear to exert diverse beneficial effects, though their mechanistic roles in myositis and other myopathologies remain poorly understood.
Laparoscopic prolapse surgery: types and evidence
Authors: Wattiez Arnaud , Nasir Razan , Al Maamari Basma , Schindler Larissa
Published: August 2016

Purpose of review

Recommendations for the surgical treatment of pelvic organ prolapse have undergone significant changes over the last few decades.

First described to be too difficult, the laparoscopic technique has gained popularity but is still controversial. The recent warning on vaginal mesh was the sign of revival and we start now to have many articles published on results and on techniques for laparoscopic prolapse repair.

Recent findings

If nothing is new in the comparison of the routes including vaginal mesh placement, the new articles are very interesting in terms of technical information and recommendations. Those articles are very important and help us understand some failures in the laparoscopic approach mainly in the anterior compartment.

New models have been created and eventually in the future, we will be able to simulate the repair on our own patients and to assess virtually the mobility of each compartment preoperatively. This will allow us to adjust and tailor the treatment to each patient.
Eating disorders in children and adolescents: what does the gynecologist need to know?
Authors: Sieke Erin H. , Rome Ellen S.
Published: August 2016

Purpose of review

The purpose of this review is to discuss the diagnosis, medical complications, and treatment of eating disorders as defined by the newly released Diagnostic and Statistical Manual, 5th edition.

Recent findings

With the introduction of the Diagnostic and Statistical Manual, 5th edition, the diagnostic criteria for anorexia nervosa and bulimia nervosa have been revised to better capture the varied presentations of patients with eating disorders. In addition, new eating disorder diagnoses including binge-eating disorder, characterized by recurrent bingeing without associated compensatory behaviors, and avoidant/restrictive food intake disorder, characterized by a restrictive eating pattern without associated body dysmorphism, allow for increased recognition, diagnosis, and treatment of disordered eating patterns. In addition to a high mortality rate, eating disorders are associated with serious medical sequelae secondary to malnutrition and disordered behaviors, including disturbances of the cardiovascular, neurologic, gastrointestinal, reproductive, and skeletal systems. Early diagnosis and family-based treatment are associated with improved outcomes in children and adolescents.

Eating disorders are illnesses with biological, psychological, and social implications that commonly present in childhood and adolescence. Gynecologists are on the front line for the screening and diagnosis of eating disorders in adolescent women.
Prosthetic Aortic Valve Fixation Study: 48 Replacement Valves Analyzed Using Digital Pressure Mapping
Authors: Lee Candice Y. , Wong Joshua K. , Ross Ronald E. , Liu David C. , Khabbaz Kamal R. , Martellaro Angelo J. , Gorea Heather R. , Sauer Jude S. , Knight Peter A.
Published: August 2016

Objective

Prostheses attachment is critical in aortic valve replacement surgery, yet reliable prosthetic security remains a challenge. Accurate techniques to analyze prosthetic fixation pressures may enable the use of fewer sutures while reducing the risk of paravalvular leaks (PVL).

Methods

Customized digital thin film pressure transducers were sutured between aortic annulus models and 21-mm bioprosthetic valves with 15 × 4-mm, 12 × 4-mm, or 9 × 6-mm-wide pledgeted mattress sutures. Simulating open and minimally invasive access, 4 surgeons, blinded to data acquisition, each secured 12 valves using manual knot-tying (hand-tied [HT] or knot-pusher [KP]) or automated titanium fasteners (TFs). Real-time pressure measurements and times were recorded. Two-dimensional (2D) and 3D pressure maps were generated for all valves. Pressures less than 80 mm Hg were considered at risk for PVL.

Results

Pressures under each knot (intrasuture) fell less than 80 mm Hg for 12 of 144 manual knots (5/144 HT, 7/144 KP) versus 0 of 288 TF (P < 0.001). Pressures outside adjacent sutures (extrasuture) were less than 80 mm Hg in 10 of 60 HT, zero of 60 KP, and zero of 120 TF sites for 15 × 4-mm valves; 17 of 48 HT, 25 of 48 KP, and 12 of 96 TF for 12 × 4-mm valves; and 15 of 36 HT, 17 of 36 KP and 9 and 72 TF for 9 × 6-mm valves; P < 0.001 all manual versus TF. Annular areas with pressures less than 80 mm Hg ranged from 0% of the sewing-ring area (all open TF) to 31% (12 × 4 mm, KP). The average time per manual knot, 46 seconds (HT, 31 seconds; KP, 61 seconds), was greater than TF, 14 seconds (P < 0.005).

Conclusions

Reduced operative times and PVL risk would fortify the advantages of surgical aortic valve replacement. This research encourages continued exploration of technical factors in optimizing prosthetic valve security.
Hedonic and motivational responses to food reward are unchanged in rats with neuropathic pain
Authors: Okun Alec , McKinzie David L. , Witkin Jeffrey M. , Remeniuk Bethany , Husein Omar , Gleason Scott D. , Oyarzo Janice , Navratilova Edita , McElroy Brian , Cowen Stephen , Kennedy Jeffrey D. , Porreca Frank
Published: August 2016

Rewards influence responses to acute painful stimuli, but the relationship of chronic pain to hedonic or motivational aspects of reward is not well understood. We independently evaluated hedonic qualities of sweet or bitter tastants and motivation to seek food reward in rats with experimental neuropathic pain induced by L5/6 spinal nerve ligation. Hedonic response was measured by implantation of intraoral catheters to allow passive delivery of liquid solutions, and “liking/disliking” responses were scored according to a facial reactivity scale. Spinal nerve ligation rats did not differ from controls in either “liking” or “disliking” reactions to intraoral sucrose or quinine, respectively, at postsurgery day 21, suggesting no differences in perceived hedonic value of sweet or bitter tastants. To assess possible motivational deficits during acute and chronic pain, we used fixed- and progressive-ratio response paradigms of sucrose pellet presentation in rats with transient inflammatory or chronic neuropathic pain. Assessment of response acquisition and break points under the progressive ratio schedule revealed no differences between sham and spinal nerve ligation rats for up to 120 days after injury. However, rats with inflammation showed decrements in lever pressing and break points on days 1 and 2 after complete Freund adjuvant injection that normalized by day 4, consistent with transient ongoing pain. Thus, although acute ongoing inflammatory pain may transiently reduce reward motivation, we did not detect influences of chronic neuropathic pain on hedonic or motivational responses to food rewards. Adaptations that allow normal reward responding to food regardless of chronic pain may be of evolutionary benefit to promote survival.
Improvements in Function and Strength with Decompressive Bracing of the Osteoarthritic Knee
Authors: Lamberg Eric M. , Streb Robert , Werner Marc , Kremenic Ian J. , Penna James
Published: August 2016

Introduction

The aim of this study was to investigate if a decompressive knee brace used in the presence of unicompartment knee osteoarthritis (OA) alters knee strength, walking endurance, balance abilities, perception of pain, symptoms, activities of daily living (ADLs), and quality of life (QoL).

Materials and Methods

Nineteen individuals with unilateral unicompartment knee OA participated. Participants wore a knee brace for 6 months that decompresses the OA compartment. Muscle strength, 6-minute walk test (6MWT) distance, and balance abilities were assessed at baseline and at 2 weeks (post) and 8 weeks (final) after receiving the brace. The Knee Osteoarthritis Outcome Survey (KOOS: domains of pain, symptoms, ADLs, and QoL) and the Activities-specific Balance Confidence (ABC) scale were used at baseline, brace fitting, post, final, 3 months, and 6 months.

Results

Muscle strength into knee extension and flexion increased at final compared with that at baseline (P < 0.05). The 6MWT distance improved by 68 m at final compared with that at baseline. Improvements on the KOOS and ABC were found at 6 months compared with that at baseline (P < 0.05). No changes in balance abilities were identified (P > 0.05).

Conclusions

Using a decompressive knee brace is beneficial for individuals with unicompartment knee OA. Brace use results in reduced pain, symptoms, improved ADLs, and QoL as well as increases in knee muscle strength and walking capacity.
Radiogenomics: towards a personalized radiation oncology
Authors: Roberson John D. , Burnett Omer L. , Robin Nathaniel
Published: August 2016

Purpose of review

This article evaluates the field of radiogenomics within recent developments in genomics and radiation biology.

Recent findings

Many pediatric cancer survivors have undergone treatment with radiation, putting them at risk for long-term side-effects associated with this therapy, especially cardiac disease and secondary malignancies. Advancements in our understanding of radiation biology have led to the understanding that genetics plays a major role in determining a patient's susceptibility to developing long-term side-effects, leading to the field of ‘radiogenomics’. Although initial candidate gene studies did not demonstrate replicable genetic variants that affected radiosensitivity, genome-wide association studies have recently begun to identify genes that may help explain some of the observed variation in radiosensitivity. As genomic sciences continues to progress and whole genome studies become more accessible, our understanding of the genes responsible for radiosensitivity will continue to progress.

The field of radiogenomics continues to evolve with the availability and improved cost of genomic technologies allowing the study of an increasing fraction of the human genome. Studies into genetic factors influencing individual radiosensitivity will increase our understanding of radiobiology and improve our ability to counsel patients on the adverse effects they will likely experience.
Navigating genetic diagnostics in patients with hearing loss
Authors: Sloan-Heggen Christina M. , Smith Richard J.H.
Published: August 2016

Purpose of review

In the age of targeted genomic enrichment and massively parallel sequencing, there is no more efficient genetic testing method for the diagnosis of hereditary hearing loss. More clinical tests are on the market, which can make choosing good tests difficult.

Recent findings

More and larger comprehensive genetic studies in patients with hearing loss have been published recently. They remind us of the importance of looking for both single nucleotide variation and copy number variation in all genes implicated in nonsyndromic hearing loss. They also inform us of how a patient's history and phenotype provide essential information in the interpretation of genetic data.

Choosing the most comprehensive genetic test improves the chances of a genetic diagnosis and thereby impacts clinical care.