bluuebunny/crossref_metadata_2025 huggingface dataset:
Method to secure the performance of the differential protection in presence of fault current limiter applied into the neutral line
Authors: Sahebi Ali , Samet Haidar , Ghanbari Teymoor
Published: July 2016

Phase‐to‐ground fault is the most probable fault type in power systems, which is generally limited through neutral grounding resistor. The grounding resistor may have negative impacts on the system such as decrease in sensitivity of the differential protection. Fault current limiter (FCL) is a suitable alternative for the grounding resistor. However, the input signals of differential protections may be adversely affected by the FCL, resulting mal‐operation of this protection. In this study, effects of FCL installed in neutral line of power transformers on the relevant differential protection algorithms are analysed. Performance of some well‐known differential protection algorithms for discrimination between internal fault and magnetising inrush currents in presence of the neutral FCL is evaluated in detail. Then, a supplementary method based on the least error squares technique is proposed to rectify the deformed portion of the current waveform due to presence of the FCL. The reconstructed signal is considered as a proper input for the discrimination algorithms. Various simulations and experiments are carried out to validate the performance of the suggested technique. The results indicate the consistency of the suggested technique for different power systems, operating conditions, and real applications.
Microwave‐based system for non‐destructive monitoring water pipe networks using support vector machine
Authors: Becari Wesley , de Oliveira Arthur M. , Peres Henrique E.M. , Correra Fatima S.
Published: July 2016

Water is the most valuable natural resource. To preserve this good, several water monitoring systems for pipe networks have been proposed. However, there is a lack of research on the development of high‐frequency electromagnetic sensors for this task. This study proposes a non‐destructive technique to locate carrying water polyvinyl chloride pipes using a microstrip patch antenna. An experimental apparatus was mounted and the resonant frequency and Q factor of the antenna were measured for different relative positions between the sensor and the pipe filled with water. To detect the pipe position, experimental data were trained and tested by applying an approach based on support vector machines. The best results were from using a simple linear kernel, which allowed 100% accuracy using a 30% fraction of data used for holdout validation.
Automatic generation control of thermal power system under varying steam turbine dynamic model parameters based on generation schedules of the plants
Authors: Pathak Nikhil , Verma Ashu , Bhatti Terlochan Singh
Published: July 2016

This paper investigates the automatic generation control (AGC) of thermal power system operating under different power generation levels/schedules of the plants. The power system load varies considerably over the period of 24 hours and accordingly thermal power plants are planned to operate at different generation schedules. It has been discovered that the steam turbine dynamic model parameters also changes along with generation schedules of the plant. Typical steam turbine model parameters are the turbine time constants and power fractions. The literature survey reveals that steam turbine dynamic model parameters are assumed to be constant in all preceding studies pertaining to AGC systems, irrespective of generation schedules of the plant. In this paper, steam turbine dynamic model parameters have been computed for an actual 500 MW thermal unit at different generation schedules. These steam turbine dynamic model parameters have been used to study the dynamic performance of AGC system. The paper also presents the general mathematical procedure to calculate steam turbine dynamic model parameters from an actual generating unit using the heat balance data of a thermal power plant. Results for two area thermal power system demonstrate the potential of the proposed approach.
Strengthened preventive start‐time optimisation that reduces congestion ratio under no failure scenario
Authors: Kaptchouang Stephane , Ouédraogo Ihsen Aziz , Oki Eiji
Published: July 2016

A conventional preventive start‐time optimisation (PSO) scheme determines a link weight set that minimises the worst congestion ratio over any link failure. However, the weight set generated by the conventional PSO creates a higher congestion ratio under no failure than an SO scheme, which minimises the congestion ratio under no failure. This study proposes a scheme to reduce the congestion ratio under no failure while keeping the same minimal worst congestion ratio under failure. Numerical results showed that the proposed scheme reduces the congestion ratio under no failure up to 29% compared with the conventional PSO in their examined networks.
Single and mechanically coupled capacitive silicon nanomechanical resonators
Authors: Van Toan Nguyen , Shimazaki Tsuyoshi , Ono Takahito
Published: July 2016

The design, fabrication and evaluation of single and mechanically coupled capacitive silicon nanomechanical resonators is reported. The structure of resonators is fabricated on a silicon on insulator wafer and transferred to a Tempax glass substrate by anodic bonding. A finite element method simulation has been conducted to investigate the vibration modes of the resonators. Single beam resonator with a length of 21.3 μm, a width of 500 nm, a thickness of 5 μm and the capacitive gap size of about 300 nm shows a nonlinear response. The amplitude of frequency response increases as the frequency is swept upward, and then suddenly jumps to a lower value. The mechanically coupled capacitive silicon nanomechanical resonator with a number of 100 individual beams above is successfully fabricated. Some resonant peaks can be observed, which shows that most nanomechanical resonators are mechanically coupled and synchronised. A mechanical resonance at a high frequency of ∼7.2 MHz in flexural mode has been detected. A small motional resistance of 1.2 kΩ has been achieved by the mechanical coupling.
Synthesis and characterisation of ceramic core/shell nanofibres via single stage co‐axial electrospinning
Authors: Rafieipour Hojjat , Vaezi Mohammad Reza , Kazemzadeh Asghar
Published: July 2016

SnO2/ZnO core–shell nanofibres were synthesised by single‐stage electrospinning technique. For synthesis of these nanofibres, the hydrophilic solutions of precursors were injected by two injectors through coaxial needles which were connected to separate syringes. The precursor's solutions were prepared by solving zinc acetate and tin chloride in polyvinyl alcohol solution, separately. The morphology and structure of nanofibres were observed by field emission scanning electron microscope, transmission electron microscopy, energy dispersive X‐ray spectroscopy and X‐ray diffraction techniques, before and after calcination. The final core/shell structure of the nanofibres was established as SnO2/ZnO, after calcination. Average diameters of the as‐eletrospun and calcined core/shell nanofibres were about 190 and 97 nm, respectively.
Initiating therapeutic relaxation in Britain: a twentieth-century strategy for health and wellbeing
Authors: Nathoo Ayesha
Published: July 2016

In 1972, a British charity, Relaxation for Living, was established “to promote the teaching of physical relaxation, to combat stress, strain, anxiety and the tension of modern life, and to reduce fatigue”. This article explores the origins and development of “physical relaxation” techniques and ideologies, starting in the interwar period, and the development of practical, therapeutic, social and cultural frameworks necessary for such an organization to come into being in 1970s Britain. It traces how relaxation was reconstituted as a scientifically-based skill that could be learnt and taught, imbued with therapeutic value for combating and preventing specific physical ailments and enhancing individual health and wellbeing. The article explores how relaxation techniques gained currency among particular demographic and clinical groups, ranging from middle-class, child-bearing women to middle-aged, “coronary-prone” men. This analysis highlights the role that relaxation practitioners played in both creating and responding to demand for individualistic health-management strategies, many of which have shaped contemporary health and wellbeing agendas. This article is published as part of a collection entitled “On balance: lifestyle, mental health and wellbeing”.
Bridging the gap between modules in isolation and as part of networks: A systems framework for elucidating interaction and regulation of signalling modules
Authors: Menon Govind , Krishnan J.
Published: July 2016

While signalling and biochemical modules have been the focus of numerous studies, they are typically studied in isolation, with no examination of the effects of the ambient network. In this paper we formulate and develop a systems framework, rooted in dynamical systems, to understand such effects, by studying the interaction of signalling modules. The modules we consider are (i) basic covalent modification, (ii) monostable switches, (iii) bistable switches, (iv) adaptive modules, and (v) oscillatory modules. We systematically examine the interaction of these modules by analyzing (a) sequential interaction without shared components, (b) sequential interaction with shared components, and (c) oblique interactions. Our studies reveal that the behaviour of a module in isolation may be substantially different from that in a network, and explicitly demonstrate how the behaviour of a given module, the characteristics of the ambient network, and the possibility of shared components can result in new effects. Our global approach illuminates different aspects of the structure and functioning of modules, revealing the importance of dynamical characteristics as well as biochemical features; this provides a methodological platform for investigating the complexity of natural modules shaped by evolution, elucidating the effects of ambient networks on a module in multiple cellular contexts, and highlighting the capabilities and constraints for engineering robust synthetic modules. Overall, such a systems framework provides a platform for bridging the gap between non-linear information processing modules, in isolation and as parts of networks, and a basis for understanding new aspects of natural and engineered cellular networks.
Microscopic origin of the charge transfer in single crystals based on thiophene derivatives: A combined NEXAFS and density functional theory approach
Authors: Chernenkaya A. , Morherr A. , Backes S. , Popp W. , Witt S. , Kozina X. , Nepijko S. A. , Bolte M. , Medjanik K. , Öhrwall G. , Krellner C. , Baumgarten M. , Elmers H. J. , Schönhense G. , Jeschke H. O. , Valentí R.
Published: July 2016

We have investigated the charge transfer mechanism in single crystals of DTBDT-TCNQ and DTBDT-F4TCNQ (where DTBDT is dithieno[2,3-d;2′,3′-d′] benzo[1,2-b;4,5-b′]dithiophene) using a combination of near-edge X-ray absorption spectroscopy (NEXAFS) and density functional theory calculations (DFT) including final state effects beyond the sudden state approximation. In particular, we find that a description that considers the partial screening of the electron-hole Coulomb correlation on a static level as well as the rearrangement of electronic density shows excellent agreement with experiment and allows to uncover the details of the charge transfer mechanism in DTBDT-TCNQ and DTBDT-F4 TCNQ, as well as a reinterpretation of previous NEXAFS data on pure TCNQ. Finally, we further show that almost the same quality of agreement between theoretical results and experiment is obtained by the much faster Z+1/2 approximation, where the core hole effects are simulated by replacing N or F with atomic number Z with the neighboring atom with atomic number Z+1/2.
Investigation of drop impact on dry and wet surfaces with consideration of surrounding air
Authors: Guo Yisen , Lian Yongsheng , Sussman Mark
Published: July 2016

Numerical simulations were conducted to investigate drop impingement and splashing on both dry and wet surfaces at impact velocities greater than 50 m/s with the consideration of the effect of surrounding air. The Navier-Stokes equations were solved using the variable density pressure projection method on a dynamic block structured adaptive grid. The moment of fluid method was used to reconstruct interfaces separating different phases. A dynamic contact angle model was used to define the boundary condition at the moving contact line. Simulations showed that lowering the ambient gas density can suppress dry surface splashing, which is in agreement with the experiments. A recirculation zone was observed inside the drop after contact: a larger recirculation zone was formed earlier in the higher gas density case than in the lower gas density case. Increasing gas density also enhances the creation of secondary droplets from the lamella breakup. For high speed impact on a dry surface, lowering ambient gas density attenuates splashing. However, ambient air does not significantly affect splashing on a wet surface. Simulations showed that the splashed droplets are primarily from the exiting liquid film.
Stability and bifurcation analysis of a generalized scalar delay differential equation
Authors: Bhalekar Sachin
Published: July 2016

This paper deals with the stability and bifurcation analysis of a general form of equation Dαx(t)=g(x(t),x(t−τ)) involving the derivative of order α ∈ (0, 1] and a constant delay τ ≥ 0. The stability of equilibrium points is presented in terms of the stability regions and critical surfaces. We provide a necessary condition to exist chaos in the system also. A wide range of delay differential equations involving a constant delay can be analyzed using the results proposed in this paper. The illustrative examples are provided to explain the theory.
Fabrication of anti-protein-fouling poly(ethylene glycol) microfluidic chip electrophoresis by sandwich photolithography
Authors: Cong Hailin , Xu Xiaodan , Yu Bing , Liu Huwei , Yuan Hua
Published: July 2016

Microfluidic chip electrophoresis (MCE) is a powerful separation tool for biomacromolecule analysis. However, adsorption of biomacromolecules, particularly proteins onto microfluidic channels severely degrades the separation performance of MCE. In this paper, an anti-protein-fouling MCE was fabricated using a novel sandwich photolithography of poly(ethylene glycol) (PEG) prepolymers. Photopatterned microchannel with a minimum resolution of 10 μm was achieved. After equipped with a conventional online electrochemical detector, the device enabled baseline separation of bovine serum albumin, lysozyme (Lys), and cytochrome c (Cyt-c) in 53 s under a voltage of 200 V. Compared with a traditional polydimethylsiloxane MCE made by soft lithography, the PEG MCE made by the sandwich photolithography not only eliminated the need of a master mold and the additional modification process of the microchannel but also showed excellent anti-protein-fouling properties for protein separation.
Effects of the population pedigree on genetic signatures of historical demographic events
Authors: Wakeley John , King Léandra , Wilton Peter R.
Published: July 2016

Genetic variation among loci in the genomes of diploid biparental organisms is the result of mutation and genetic transmission through the genealogy, or population pedigree, of the species. We explore the consequences of this for patterns of variation at unlinked loci for two kinds of demographic events: the occurrence of a very large family or a strong selective sweep that occurred in the recent past. The results indicate that only rather extreme versions of such events can be expected to structure population pedigrees in such a way that unlinked loci will show deviations from the standard predictions of population genetics, which average over population pedigrees. The results also suggest that large samples of individuals and loci increase the chance of picking up signatures of these events, and that very large families may have a unique signature in terms of sample distributions of mutant alleles.
Silencing of natural transformation by an RNA chaperone and a multitarget small RNA
Authors: Attaiech Laetitia , Boughammoura Aïda , Brochier-Armanet Céline , Allatif Omran , Peillard-Fiorente Flora , Edwards Ross A. , Omar Ayat R. , MacMillan Andrew M. , Glover Mark , Charpentier Xavier
Published: July 2016

Significance

Natural transformation is a major mechanism of horizontal gene transfer (HGT) by which bacteria take up exogenous DNA directly in their environment and integrate it in their genome. Acquiring new genetic information may confer an adaptive advantage but an uncontrolled uptake of foreign DNA may be harmful. We document a previously unsuspected means to control HGT by natural transformation in the human pathogen
Legionella pneumophila
. We found that the DNA uptake system required for natural transformation is subjected to silencing. A member of the widespread ProQ/FinO domain-containing protein family acts as an RNA chaperone and allows the targeting of the mRNAs of the genes coding the DNA uptake system by a newly identified
trans
-acting small RNA.
Flexible, symmetry-directed approach to assembling protein cages
Authors: Sciore Aaron , Su Min , Koldewey Philipp , Eschweiler Joseph D. , Diffley Kelsey A. , Linhares Brian M. , Ruotolo Brandon T. , Bardwell James C. A. , Skiniotis Georgios , Marsh E. Neil G.
Published: July 2016

Significance

The ability to organize biological molecules into new hierarchical forms represents an important goal in synthetic biology. However, designing new quaternary interactions between protein subunits has proved technically challenging and has generally required extensive redesign of protein−protein interfaces. Here, we demonstrate a conceptually simple way to assemble a protein into a well-defined geometric structure that uses coiled-coil sequences as “off-the-shelf” components. This approach is inherently modular and adaptable to a wide range of proteins and symmetries, opening up avenues for the construction of biological structures with diverse geometries and wide-ranging functionalities.
Stepwise isotope editing of [FeFe]-hydrogenases exposes cofactor dynamics
Authors: Senger Moritz , Mebs Stefan , Duan Jifu , Wittkamp Florian , Apfel Ulf-Peter , Heberle Joachim , Haumann Michael , Stripp Sven Timo
Published: July 2016

Significance

[FeFe]-hydrogenases are H
2
-forming enzymes with potential in renewable energy applications. Their molecular mechanism of catalysis needs to be understood. A protocol for specific
13
CO isotope editing of all carbon monoxide ligands at the six-iron cofactor (H-cluster) was established. Analysis of vibrational modes via quantum chemical calculations implies structural dynamics at the H-cluster in the active-ready state. Site-selective introduction of isotopic reporter groups opens new perspectives to identify intermediates in the catalytic cycle.
Deletion of
DXZ4
on the human inactive X chromosome alters higher-order genome architecture
Authors: Darrow Emily M. , Huntley Miriam H. , Dudchenko Olga , Stamenova Elena K. , Durand Neva C. , Sun Zhuo , Huang Su-Chen , Sanborn Adrian L. , Machol Ido , Shamim Muhammad , Seberg Andrew P. , Lander Eric S. , Chadwick Brian P. , Aiden Erez Lieberman
Published: July 2016

Significance

In human females, one of the two X chromosomes is inactive (Xi) and adopts an unusual 3D conformation. The Xi chromosome contains superloops, large chromatin loops that are often anchored at the macrosatellite repeat
DXZ4
, and is partitioned into two large intervals, called superdomains, whose boundary lies at
DXZ4
. Here, we use spatial proximity mapping, microscopy, and genome editing to study the Xi. We find that superloops and superdomains are conserved across humans, macaque, and mouse. By mapping proximity between three or more loci, we show that superloops tend to occur simultaneously. Deletion of
DXZ4
from the human Xi disrupts superloops, eliminates superdomains, and alters chromatin modifications. Finally, we show that a model in which CCCTC-binding factor (CTCF) and cohesin extrude chromatin can explain the formation of superloops and superdomains.
No future? Narrating the past in Bosnian history museums
Authors: Puttkamer Joachim von
Published: July 2016

Recent unrest and the 2014 elections have corroborated the impression of Bosnia as a failing state, one that is constantly being undermined by the three-way impasse between constituent ethnic groups of Bosniaks, Croats, and Serbs. Major history museums in Bosnia, however, provide a more complex picture. This paper analyzes museums and exhibitions on twentieth-century history in Sarajevo, Banja Luka, and Jajce, with regard to their narrative strategies, their aesthetic appearance, and the commemorative practices in their respective locations. From this perspective, the use of history in building group identity in Bosnia is far from coherent. Although museums are one means to assert firmly entrenched national identities both old and new, they compete at the same time with nostalgic commemorations of socialist Yugoslavia and with equally nostalgic references to the Austrian occupation. Various civic groups struggle to assert their visions of belonging, mostly with rather modest financial means. Based on these findings, this paper will explore not only the underlying assumptions of what history and, in particular, museums are all about, but also how visions of the future of Bosnia and Herzegovina are inscribed in these uses of history – if indeed they are.
Stroop-Like Effects in a New-Code Learning Task: A Cognitive Load Theory Perspective
Authors: Hazan-Liran Batel , Miller Paul
Published: July 2016

To determine whether and how learning is biased by competing task-irrelevant information that creates extraneous cognitive load, we assessed the efficiency of university students with a learning paradigm in two experiments. The paradigm asked participants to learn associations between eight words and eight digits. We manipulated congruity of the digits’ ink colour with the words’ semantics. In Experiment 1 word stimuli were colour words (e.g., blue, yellow) and in Experiment 2 colour-related word concepts (e.g., sky, banana). Marked benefits and costs on learning due to variation in extraneous cognitive load originating from processing task-irrelevant information were evident. Implications for cognitive load theory and schooling are discussed.
Grasping remaps the distribution of visuospatial attention and enhances competing action activation
Authors: Colman Hayley , Remington Roger , Kritikos Ada
Published: July 2016

We examined how action goals influence the distribution of visuospatial attention near the body (Experiment 1) and how the temporal relationship between distractors and targets modifies shifts in visuospatial attention (Experiment 2). Targets were light emitting diodes (LEDs) in the left and right hemispace of a visual display. Following left or right target illumination, participants reached to point-to or grasp target object in blocked trials. Coincident with target onset, a distractor LED illuminated in the same or opposite hemispace between the initiation point and target, or no distractor appeared. In Experiment 1, during grasping there was a larger temporal interference effect (slower reach initiation) than with pointing. When grasping versus pointing, participants deviated more towards same-side distractors and away from opposite-side distractors. In Experiment 2, distractors onset 200ms prior to (−200-ms), coincident with (0 ms), or 200ms following (+200 ms) the target. For both reach types, −200-ms distractors had greater onset temporal interference than 0 ms and +200-ms distractors. For grasping, +200 ms distractors had larger temporal interference than 0 ms distractors. For −200-ms, reach trajectories deviated more towards opposite-side distractors and away from same-side distractors, the reverse of the pattern for 0 ms and +200-ms distractors.
SIM.M.FF-S7: Final report on SIM/ANDIMET supplementary comparison for volume of liquids at 100 mL and 100 μL
Authors: Trujillo S , Maldonado J M , Vega M C , Santalla E , Sica A , Cantero D , Salazar M , Morales A , Solano P , Rodríguez L D
Published: July 2016

A SIM/ANDIMET comparison for liquid volume using two 100 mL pycnometers and two 100 μL piston pipettes was performed between January 2012 and October 2013. The National Metrology Institute (NMI) of Bolivia was the coordinating laboratory and the Mexican NMI provided technical assistance. The participating labs were IBMETRO (Bolivia), INM (Colombia), INEN (Ecuador), INDECOPI (Peru), LACOMET (Costa Rica), LATU (Uruguay), INTN (Paraguay), and CENAM (Mexico). Based on measurements made by CENAM at the beginning and end of the comparison, the transfer standards were stable during the comparison within 0.0001 mL for the 100 mL pycnometers and 0.03 μL for the 100 μL pipettes. For 100 mL, six of the eight participants agreed within ± 0.003 % and had standardized degrees of equivalence (EN) less than 1. Two participants (INEN and INM) had EN values greater than 1. For the 100 μL pipettes, the results were corrected for the influence of altitude and seven of the eight participants agreed within ± 0.3 %. Results from INEN and some from INM and IBMETRO had EN values greater than 1 for the 100 μL pipettes. Uncertainties recommended by Guideline DKD-R 8-1 for micropipettes were included.

Main text

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.

The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Family-Joining: A Fast Distance-Based Method for Constructing Generally Labeled Trees
Authors: Kalaghatgi Prabhav , Pfeifer Nico , Lengauer Thomas
Published: July 2016

The widely used model for evolutionary relationships is a bifurcating tree with all taxa/observations placed at the leaves. This is not appropriate if the taxa have been densely sampled across evolutionary time and may be in a direct ancestral relationship, or if there is not enough information to fully resolve all the branching points in the evolutionary tree. In this article, we present a fast distance-based agglomeration method called family-joining (FJ) for constructing so-called generally labeled trees in which taxa may be placed at internal vertices and the tree may contain polytomies. FJ constructs such trees on the basis of pairwise distances and a distance threshold. We tested three methods for threshold selection, FJ-AIC, FJ-BIC, and FJ-CV, which minimize Akaike information criterion, Bayesian information criterion, and cross-validation error, respectively. When compared with related methods on simulated data, FJ-BIC was among the best at reconstructing the correct tree across a wide range of simulation scenarios. FJ-BIC was applied to HIV sequences sampled from individuals involved in a known transmission chain. The FJ-BIC tree was found to be compatible with almost all transmission events. On average, internal branches in the FJ-BIC tree have higher bootstrap support than branches in the leaf-labeled bifurcating tree constructed using RAxML. 36% and 25% of the internal branches in the FJ-BIC tree and RAxML tree, respectively, have bootstrap support greater than 70%. To the best of our knowledge the method presented here is the first attempt at modeling evolutionary relationships using generally labeled trees.
Worms at Work: Long-run Impacts of a Child Health Investment*
Authors: Baird Sarah , Hicks Joan Hamory , Kremer Michael , Miguel Edward
Published: July 2016

This study estimates long-run impacts of a child health investment, exploiting community-wide experimental variation in school-based deworming. The program increased labor supply among men and education among women, with accompanying shifts in labor market specialization. Ten years after deworming treatment, men who were eligible as boys stay enrolled for more years of primary school, work 17% more hours each week, spend more time in nonagricultural self-employment, are more likely to hold manufacturing jobs, and miss one fewer meal per week. Women who were in treatment schools as girls are approximately one quarter more likely to have attended secondary school, halving the gender gap. They reallocate time from traditional agriculture into cash crops and nonagricultural self-employment. We estimate a conservative annualized financial internal rate of return to deworming of 32%, and show that mass deworming may generate more in future government revenue than it costs in subsidies.
Doctors as Makers
Authors: Baruch Jay M.
Published: July 2016

Traditional skills and expertise are not enough to prepare future physicians for the complexity, instability, and uncertainty of clinical practice. Responding and making meaning from ill-defined or unusual problems calls for, even demands, creativity. In this article, the author suggests expanding the traditional role of doctor as science-using, evidence-based practitioner to include that of doctor as a “maker” (creator) and artist. Such a reimagining requires a shift in how we view medical knowledge and patients’ stories, as well as a new appreciation for “not-knowing” as a generative, creative space in medicine. Creative thinking deserves a central place in the training of doctors, driven by a reconceptualization of the traditional educational model to include medical disciplines, humanities scholars, artists, and designers.
The Mediating Effects of the Different Dimensions of Pain Catastrophizing on Outcomes in an Interdisciplinary Pain Rehabilitation Program
Authors: Gilliam Wesley P. , Craner Julia R. , Morrison Eleshia J. , Sperry Jeannie A.
Published: July 2016

Objective:

Although reducing pain catastrophizing has been shown to contribute to functional improvement in patients receiving interdisciplinary pain care, little is known about how changes in the different dimensions of pain catastrophizing uniquely contribute to improvement in outcome. The study examined the unique relationship between changes in the 3 distinct factors of pain catastrophizing—helplessness, rumination, and magnification—and changes in pain outcomes.

Materials and Methods:

In this nonrandomized study, 641 patients who completed treatment in a 3-week interdisciplinary pain rehabilitation program between the years 2013 and 2014 completed a battery of psychometrically validated measures of pain catastrophizing, pain severity, pain interference, mental and physical health-related quality of life, and depressive symptoms at pretreatment and posttreatment.

Results:

A series of within groups (repeated measures) mediation analyses were conducted. Change in the helplessness, rumination, and magnification subscales were entered as multiple mediators in the model. Analyses revealed that change in helplessness partially mediated improvement in all outcome variables beyond the influence of change in other variables in the model, whereas change in rumination partially mediated improvement in pain severity, interference, and depressive symptoms. Change in magnification had the least impact on outcome, partially mediating improvements in only mental health quality of life.

Discussion:

Results suggest that changes in the 3 dimensions of pain catastrophizing differentially mediate improvement in pain outcome. Treatment approaches that specifically target helplessness and rumination may be particularly useful in improving the outcomes of patients with refractory pain conditions enrolled in interdisciplinary pain rehabilitation program.
Multisite Randomized Controlled Trial to Compare Two Methods of Tinnitus Intervention to Two Control Conditions
Authors: Henry James A. , Stewart Barbara J. , Griest Susan , Kaelin Christine , Zaugg Tara L. , Carlson Kathleen
Published: July 2016

Objectives:

In this four-site clinical trial, we evaluated whether tinnitus masking (TM) and tinnitus retraining therapy (TRT) decreased tinnitus severity more than the two control groups: an attention-control group that received tinnitus educational counseling (and hearing aids if needed; TED), and a 6-month-wait-list control (WLC) group. The authors hypothesized that, over the first 6 months of treatment, TM and TRT would decrease tinnitus severity in Veterans relative to TED and WLC, and that TED would decrease tinnitus severity relative to WLC. The authors also hypothesized that, over 18 months of treatment, TM and TRT would decrease tinnitus severity relative to TED. Treatment effectiveness was hypothesized not to be different across the four sites.

Design:

Across four Veterans affairs medical center sites, N = 148 qualifying Veterans who experienced sufficiently bothersome tinnitus were randomized into one of the four groups. The 115 Veterans assigned to TM (n = 42), TRT (n = 34), and TED (n = 39) were considered immediate-treatment subjects; they received comparable time and attention from audiologists. The 33 Veterans assigned to WLC were, after 6 months, randomized to receive delayed treatment in TM, TRT, or TED. Assessment of outcomes took place using the Tinnitus Handicap Inventory (THI) at 0, 3, 6, 12, and 18 months.

Results:

Results of a repeated measures analysis of variance using an intention-to-treat approach showed that the tinnitus severity of Veterans receiving TM, TRT, and TED significantly decreased (p < 0.05) relative to Veterans in the WLC group at 3 months (effect sizes = 0.44, 0.52, and 0.27, respectively) and at 6 months (effect sizes = 0.52, 0.56, and 0.40, respectively). Analyses comparing effectiveness of TM, TRT, and TED over 18 months revealed that the three conditions were not significantly different, but that tinnitus severity in the combined groups significantly decreased (p < 0.01) from baseline to 3 months (5.6 THI points) and from 3 to 6 months (3.7 THI points). With respect to clinically significant change, about half of Veterans who received TM (55%), TRT (59%), or TED (46%) showed strong or modest improvement on the THI by 18 months. Without treatment, the WLC group did not show significant change. Treatment effectiveness did not differ by study site.

Conclusions:

Audiologists who provided interventions to Veterans with bothersome tinnitus in the regular clinic setting were able to significantly reduce tinnitus severity over 18 months using TM, TRT, and TED approaches. These results suggest that TM, TRT, and TED, when implemented as in this trial, will provide effectiveness that is relatively similar by 6 months and beyond.
Double V-Y Flap to Cover the Fingertip Injury: New Technique and Cases
Authors: Díaz Luis C. , Vergara-Amador Enrique , Fuentes Losada Lina M.
Published: July 2016

The volar V-Y flap is used in transverse or dorsal oblique amputations in fingertip injuries; however, its use is contraindicated in patients with volar oblique amputations and cannot advance distally enough to cover the defect. The aim of this report is to describe a technique of double V-Y flap to cover fingertip defects in which a simple V-Y flap is not enough. This technique allows advancement between 30% and 50% farther than the original, simple V-Y flap. Report of cases a series of fingertip amputation covered with this technique. This technique was performed in 7 patients between 25 and 64 years old, with transverse, volar and dorsal oblique defects in the fingertip. The advancing of the flap was between 3 and 5 mm. There were no infections or necrosis of the flaps. In all patients there were acceptable aesthetic results with 2-point discrimination between 4 and 6 mm in the proximal flap and up to 10 mm in the distal flap with a minimum follow-up of 6 months. With this double V-Y flap, we have seen a good coverage even in volar oblique amputation. In addition, it is possible to advance up to 5 mm more with this second V-Y flap without compromising the vitality of the flap. It is a simple and reproducible technique that can be used on any finger, with good results, without flap necrosis.
Platelet Count Trends and Prevalence of Heparin-Induced Thrombocytopenia in a Cohort of Extracorporeal Membrane Oxygenator Patients
Authors: Sokolovic Mladen , Pratt Alexandra K. , Vukicevic Vladimir , Sarumi Molly , Johnson Laura S. , Shah Nimesh S.
Published: July 2016

Objectives:

To assess the prevalence of heparin-induced thrombocytopenia and to study platelet count trends potentially suggestive of heparin-induced thrombocytopenia in a population of extracorporeal membrane oxygenator patients.

Design:

Retrospective cohort study.

Setting:

A total of 926-bed teaching hospital.

Patients:

Extracorporeal membrane oxygenator patients who survived longer than 48 hours from extracorporeal membrane oxygenator initiation between January 1, 2009, and December 31, 2013.

Interventions:

None.

Measurements and Main Results:

Demographic and clinical data were collected prospectively on all extracorporeal membrane oxygenator patients. Heparin-induced thrombocytopenia testing results and platelet count variables were obtained from the electronic medical record. We used our institutional algorithm to interpret the results of heparin-induced thrombocytopenia testing. Ninety-six extracorporeal membrane oxygenator patients met the inclusion criteria. Eight patients met the algorithm criteria for heparin-induced thrombocytopenia diagnosis and seven of those had documented thromboembolic event while on extracorporeal membrane oxygenator (prevalence of heparin-induced thrombocytopenia and heparin-induced thrombocytopenia related thrombosis, 8.3 and 7.3, respectively). Heparin-induced thrombocytopenia positive patients were younger; all underwent venoarterial extracorporeal membrane oxygenator; spent more hours on extracorporeal membrane oxygenator; had significantly higher heparin-induced thrombocytopenia enzyme-linked immunosorbent assays optical density; had a higher prevalence of thromboembolic events and reached platelet count nadir later. There was no difference in mortality between heparin-induced thrombocytopenia positive and negative patients. Comparison of platelet count trends revealed that there was no statistically significant difference between the predefined study groups.

Conclusions:

Prevalence of heparin-induced thrombocytopenia and heparin-induced thrombocytopenia-related thrombosis among extracorporeal membrane oxygenator patients at our institution is relatively high. Using platelet count trends to guide decision to test for heparin-induced thrombocytopenia is not an optimal strategy in extracorporeal membrane oxygenator patients. Without a validated pretest probability clinical score, serosurveillance in a defined high-risk group of extracorporeal membrane oxygenator patients may be needed.
False-negative rate cannot be reduced by lowering the haemoglobin concentration cut-off in colorectal cancer screening using faecal immunochemical test
Authors: Ibañez-Sanz Gemma , Garcia Montse , Milà Núria , Rodríguez-Moranta Francisco , Binefa Gemma , Gómez-Matas Javier , Benito Llúcia , Padrol Isabel , Barenys Mercè , Moreno Victor
Published: July 2016

The aim of this study was to analyse false-negative (FN) results of the faecal immunochemical test (FIT) and its determinants in a colorectal cancer screening programme in Catalonia. We carried out a cross-sectional study among 218 screenees with a negative FIT result who agreed to undergo a colonoscopy. A false-negative result was defined as the detection, at colonoscopy, of intermediate/high-risk polyps or colorectal cancer in a patient with a previous negative FIT (<20 µgHb/g). Multivariate logistic regression models were constructed to identify sociodemographic (sex, age) and screening variables (quantitative faecal haemoglobin, colonoscopy findings) related to FN results. Adjusted odds ratios and their 95% confidence intervals were estimated. There were 15.6% FN FIT results. Faecal haemoglobin was undetected in 45.5% of these results and was below 4 µgHb/g in 94.0% of the individuals with a FN result. About 60% of the lesions were located in the proximal colon, whereas the expected percentage was 30%. Decreasing the positivity threshold of FIT does not increase the detection rate of advanced neoplasia, but may increase the costs and potential adverse effects.
Association between circulatory levels of adipokines and bone mineral density in postmenopausal women
Authors: Cervellati Carlo , Bonaccorsi Gloria , Bergamini Carlo M. , Fila Enrica , Greco Pantaleo , Valacchi Giuseppe , Massari Leo , Gonelli Arianna , Tisato Veronica
Published: July 2016

Objective:

Epidemiological evidence indicates that excess fat may be beneficial for bone health, offering protective effects against the onset of postmenopausal osteoporosis. Experimental data suggest that this link might be due to the direct effect of adipokines on bone tissue. Confirmatory evidence of this association, however, remains limited.

Methods:

The levels of a panel of selected adipokines including interleukin (IL)-6, -8, -1β, adipsin, lipocalin-2/neutrophil gelatinase-associated ipocalin, tumor necrosis factor alpha, monocyte chemoattractant protein-1, plasminogen activator inhibitor-1, hepatocyte growth factor, resistin, leptin, and adiponectin in a group of osteopenic and osteoporotic postmenopausal women were compared with those of unaffected women (n = 127).

Results:

Univariate analysis revealed that leptin and adiponectin were significantly correlated with bone mineral density (BMD). In particular, leptin was positively associated with BMD of the spine (r = 0.22, P < 0.05), femoral neck (r = 0.23, P < 0.05), trochanter (r = 0.20, P < 0.05), and total hip (r = 0.27, P < 0.01), whereas adiponectin was inversely correlated with BMD at the trochanter (r = −0.21, P < 0.05). No correlations were, however, significant after adjusting for body fat variables. Stratification of the sample according to IL-6 levels revealed that adiponectin remained significantly inversely associated with BMD, regardless of fat levels and age (β=−0.29, P < 0.05; r
2 = 0.198) in the subgroup of participants with low levels of IL-6.

Conclusions:

Our data suggest that circulating adiponectin is inversely associated with markers of bone health in postmenopausal women, and that the interaction is influenced by IL-6 levels.
Ospemifene's effect on vasomotor symptoms: a post hoc analysis of phase 2 and 3 clinical data
Authors: Constantine Ginger D. , Archer David F. , Pollycove Ricki , Jiang Wei , Altomare Corrado , Pinkerton JoAnn V.
Published: July 2016

Objective:

To examine the effect of ospemifene 60 mg/d on vasomotor symptoms in postmenopausal women using clinical safety and efficacy data from five phase 2 and 3 studies.

Methods:

The incidence of hot flush treatment-emergent adverse events (TEAEs) was compiled from five randomized, placebo-controlled clinical studies; baseline parameters associated with hot flush incidence were also identified. Ospemifene's effects on the frequency and severity of hot flushes were evaluated in a previously unpublished, 6-week, placebo-controlled study.

Results:

Analysis of pooled hot flush TEAE data for 2,166 women showed an incidence of hot flush of 8.5% for ospemifene and 3.2% for placebo (P < 0.0001). Hot flushes were most frequent during the first 4 weeks of ospemifene treatment and decreased in frequency thereafter. Logistic regression analysis revealed that hormone therapy within 6 months before study start (P = 0.0234), longer study treatment duration (P = 0.0234), and more hot flush days per month at baseline (P = 0.0313) were associated with more hot flushes. Ospemifene 60 mg/d did not worsen the frequency and severity of existing hot flushes in a 6-week, placebo-controlled trial of 198 postmenopausal women who were experiencing moderate to very severe hot flushes.

Conclusions:

In randomized trials, hot flush TEAEs were more frequent with ospemifene 60 mg/d than with placebo, particularly among women with prior history of hormone therapy use. The majority of hot flushes, however, waned after 4 weeks of ospemifene treatment. Ospemifene did not worsen existing hot flushes in women experiencing moderate to very severe hot flushes.
Bone loss after oophorectomy among high-risk women: an NRG oncology/gynecologic oncology group study
Authors: Hibler Elizabeth A. , Kauderer James , Greene Mark H. , Rodriguez Gustavo C. , Alberts David S.
Published: July 2016

Objective:

Women undergoing premenopausal oophorectomy for a variety of reasons, including to reduce ovarian or breast cancer risk were evaluated for accelerated bone loss.

Methods:

The Gynecologic Oncology Group (GOG)-0215 randomized phase-II trial of zoledronic acid was initiated to determine if postoophorectomy bisphosphonate therapy could prevent this bone loss. The study was closed after slow accrual prevented evaluation of the primary study endpoint. We analyzed changes in bone mineral density (BMD) among the 80 women randomized to the observation arm of this study, as measured 3, 9, and 18 months postenrollment.

Results:

The mean change in BMD from baseline to 18 months was −0.09 (95% CI, −0.12 to −0.07), −0.05 (95% CI, −0.07 to −0.03), and −0.06 (95% CI, −0.07 to −0.05) g/cm2 across the lumbar spine, right hip, and left hip, respectively. This represents a BMD decrease of −8.5% for the lumbar spine and −5.7% for both the right and left hips from baseline to 18 months’ observation.

Conclusions:

These results demonstrate that premenopausal women undergoing oophorectomy clearly experience bone loss, an adverse effect of oophorectomy, which requires attention and active management. BMD should be monitored postoophorectomy, and treated per standard practice guidelines. Future studies will be required to determine if early treatment can mitigate fracture risk, and to test promising therapeutic interventions and novel prevention strategies, such as increased physical activity or alternative medications, in randomized trials.
Use of Intraoperative Indocyanine Green Videoangiography to Guide Cutaneous Angiosarcoma Excision
Authors: Ko Wai Shan , Tan Teresa , Mo Kevin W. L. , Wong Pauline S. Y. , Chiu Tor
Published: July 2016

Complete excision of cutaneous angiosarcoma, which is a rare, vascular, and aggressive tumor, is challenging. Its multifocal nature and propensity for lateral spread make the gross assessment of surgical margins difficult. Neither the use of frozen section analysis nor Mohs surgery consistently improves the probability of margin-free excision. Recent studies have advocated the use of indocyanine green to evaluate the vascular system perioperatively. We describe the intraoperative use of indocyanine green to help define the excision margin of a locally extensive scalp angiosarcoma in an elderly man.
Neuroepithelial Cyst of the Optic Nerve in a Newborn
Authors: Mehta Viraj J. , Chelnis James G. , Nickols Hilary H. , Mawn Louise A.
Published: July 2016

Cystic lesions of the optic nerve are uncommon findings that have been associated with neoplasms, systemic disorders, or described as idiopathic. They have been described in a wide range of ages, with few congenital cysts having been described in infants. Surgical excision of these lesions may lead to significant morbidity as previously reported cases often involved transection of the optic nerve. The authors describe a unique case of a newborn with a rare neuroepithelial cyst of the intraorbital optic nerve that was successfully excised while sparing the optic nerve, ultimately resulting in the resolution of an afferent pupillary defect. This case demonstrates that careful surgical excision of a benign optic nerve cyst can be performed without significant morbidity to potentially preserve vision.