bluuebunny/crossref_metadata_2025_split huggingface dataset:
MitraClip procedure with two MitraClips after indirect annuloplasty with the MONARC device
Authors: Rutschow Susanne , Jäger Sebastian , Gross Michael C. 
Published: December 2014

Abstract
Mitral regurgitation is associated with a worsened prognosis in dilated cardiomyopathy. First standard therapy consists of a mitral valve reconstruction through heart surgery including the heart–lung machine. In patients with high comorbidity, catheter-based techniques have been developed. In the Evolution I study, the MONARC system was implanted in the coronary sinus in the functional mitral regurgitation. A reduction in regurgitation by >1 grade was documented in 50% of the patients. MitraClip is an alternative, edge-to-edge technique, which joined the posterior and anterior leaflet by implanting a clip. It can be used for both functional and degenerative mitral regurgitations. We reported a case of MitraClip procedure with the use of two clips and a reduction of mitral regurgitation to grade 0–1 after implanting a MONARC device four years ago with missing relevant reduction in mitral regurgitation. With this report, we illustrated the management of Mitraclip in a patient with an implanted MONARC device and technical difficulties through the bowing of the posterior annulus.
“Are we architects or construction workers?” Re-examining teacher autonomy and turnover in charter schools
Authors: Torres A. Chris 
Published: December 2014

Charter school teachers nationwide expressed greater autonomy compared to traditional public school teachers at the turn of the century. But is this trend changing? The recent proliferation of Charter Management Organizations (CMOs), which often have prescriptive organizational models, has raised questions around how teachers perceive autonomy and control in these schools. Researchers consistently find that faculty input into decision-making has a strong influence on staff commitment and turnover. This exploratory, interview-based study critically examines why and how CMO teacher autonomy is linked to turnover. CMO teachers linked various concerns over autonomy, which was limited by their organization’s model, with decisions to leave their jobs. Teachers with strong expectations for autonomy or ideas inconsistent with their school’s model experienced substantial conflict involving the discipline or socialization of students that affected their career decisions. Teachers’ desires to have a voice in issues surrounding students’ socialization ultimately hinged upon their skepticism that current practices were adequately preparing students for college and life.
Femtosecond laser full and partial texturing of steel surfaces to reduce friction in lubricated contact
Authors: Ancona Antonio , Carbone Giuseppe , De Filippis Michele , Volpe Annalisa , Lugarà Pietro Mario 
Published: December 2014

Abstract
Minimizing mechanical losses and friction in vehicle engines would have a great impact on reducing fuel consumption and exhaust emissions, to the benefit of environmental protection. With this scope, laser surface texturing (LST) with femtosecond pulses is an emerging technology, which consists of creating, by laser ablation, an array of high-density microdimples on the surface of a mechanical device. The microtexture decreases the effective contact area and, in case of lubricated contact, acts as oil reservoir and trap for wear debris, leading to an overall friction reduction. Depending on the lubrication regime and on the texture geometry, several mechanisms may concur to modify friction such as the local reduction of the shear stress, the generation of a hydrodynamic lift between the surfaces or the formation of eddy-like flows at the bottom of the dimple cavities. All these effects have been investigated by fabricating and characterizing several LST surfaces by femtosecond laser ablation with different features: partial/full texture, circular/elliptical dimples, variable diameters, and depths but equivalent areal density. More than 85% of friction reduction has been obtained from the circular dimple geometry, but the elliptical texture allows adjusting the friction coefficient by changing its orientation with respect to the sliding direction.
Multi-pass absorption spectroscopy for H2O2 detection using a CW DFB-QCL
Authors: Cao Yingchun , Sanchez Nancy P. , Jiang Wenzhe , Ren Wei , Lewicki Rafał , Jiang Dongfang , Griffin Robert J. , Tittel Frank K. 
Published: December 2014

Abstract
Hydrogen peroxide (H2O2) detection was demonstrated with multi-pass absorption spectroscopy using a commercial 76-m astigmatic multi-pass absorption cell. An ∼7.73-μm continuous wave, distributed feedback quantum cascade laser (CW DFB-QCL) was employed for targeting a strong H2O2 line (1296.2 cm-1) in the fundamental absorption band. Wavelength modulation spectroscopy combined with a second harmonic detection technique was utilized to increase the signal-to-noise ratio. By optimizing the pressure inside the multi-pass cell and the wavelength modulation depth, a minimum detection limit (1σ) of 13.4 ppbv was achieved for H2O2 with a 2-s sampling time. From an Allan-Werle deviation plot, the detection limit could be improved to 1.5 ppbv with an averaging time of 200 s. Interference effects of atmospheric air components are also discussed.
On *-n-derivations in rings with involution
Authors: Ashraf Mohammad , Siddeeque Mohammad Aslam 
Published: December 2014

Abstract
Let R be a *-ring. In this paper we introduce the notion of *-n-derivation in R. An additive mapping x ↦ x*
of R into itself is called an involution on R if it satisfies the conditions: (i) (x
*)* = x, (ii) (x
y)* = y*

x*
for all
x,y ∈ R. A ring R equipped with an involution `*' is called a *-ring. It is shown that if a prime *-ring R admits a nonzero *-n-derivation (resp. a reverse *-n-derivation) D, then R is commutative. Further, some related properties of *-n-derivation in a semiprime *-ring have also been investigated. Finally, a structure theorem for *-n-derivation has been obtained.
Synthesis of iron-doped resorcinol formaldehyde-based aerogels for the removal of Cr(VI) from water
Authors: Verma Naveen Kumar , Khare Prateek , Verma Nishith 
Published: December 2014

AbstractIron-doped resorcinol formaldehyde-based aerogels (Fe-RF-AGs) were synthesized and used for the removal of hexavalent chromium [Cr(VI)] from water using adsorption. The synthesis steps of Fe-RF-AGs comprised the gelation by the polycondensation of resorcinol and formaldehyde, followed by drying using supercritical carbon dioxide. The produced mesoporous material was
Thermal Conductivity and Viscosity of Vegetable Oil–Based Cu, Zn, and Cu–Zn Hybrid Nanofluids
Authors: Kumar Mechiri Sandeep , Vasu V. , Gopal A. Venu 
Published: December 2014

Abstract
Sustainable manufacturing can be considered as one of the most important issues, which use the processes that play down negative environmental impacts in pursuing the bigger picture of sustainable development. An eco-friendly cutting fluid will go along with machining to achieve relative sustainability. To achieve relative sustainability level in machining, eco-friendly nanofluids are developed in this paper. Nanofluid is a stable colloidal suspension of ultrafine solid particles in a nanometric dimension dispersed in conventional and lubrication fluids. A two-step approach of synthesis of Zn, Cu, and Cu–Zn nanoparticles by mechanical alloying, followed by dispersing them in a base fluid (vegetable oil) to prepare nanofluids has been adopted. Powder particles were characterized by x-ray diffraction (XRD) and a particle-size analyzer. It is found from the XRD results that the crystallite size was around 26 nm for Cu powders, 59 nm for Zn powders, and 25 nm for Cu–Zn alloy after 60 h of milling. The particles size reduced to 60 nm for Zn, 60 nm for Cu, and 70 nm for Cu–Zn alloy after 60 h of milling. The enhanced thermal conductivity for Zn, Cu, and Cu–Zn nanofluids were 36 %, 42 %, and 48 %, respectively, with a volume concentration of 0.5 %, compared to base fluid (vegetable oil). The enhancement in viscosity for Zn, Cu, and Cu–Zn nanofluids are 47 %, 53 %, and 61 %, respectively, with a volume fraction of 0.5 % were reported.
A High-Density Linkage Map for Astyanax mexicanus Using Genotyping-by-Sequencing Technology
Authors: Carlson Brian M , Onusko Samuel W , Gross Joshua B 
Published: December 2014

Abstract
The Mexican tetra, Astyanax mexicanus, is a unique model system consisting of cave-adapted and surface-dwelling morphotypes that diverged &gt;1 million years (My) ago. This remarkable natural experiment has enabled powerful genetic analyses of cave adaptation. Here, we describe the application of next-generation sequencing technology to the creation of a high-density linkage map. Our map comprises more than 2200 markers populating 25 linkage groups constructed from genotypic data generated from a single genotyping-by-sequencing project. We leveraged emergent genomic and transcriptomic resources to anchor hundreds of anonymous Astyanax markers to the genome of the zebrafish (Danio rerio), the most closely related model organism to our study species. This facilitated the identification of 784 distinct connections between our linkage map and the Danio rerio genome, highlighting several regions of conserved genomic architecture between the two species despite ∼150 My of divergence. Using a Mendelian cave-associated trait as a proof-of-principle, we successfully recovered the genomic position of the albinism locus near the gene Oca2. Further, our map successfully informed the positions of unplaced Astyanax genomic scaffolds within particular linkage groups. This ability to identify the relative location, orientation, and linear order of unaligned genomic scaffolds will facilitate ongoing efforts to improve on the current early draft and assemble future versions of the Astyanax physical genome. Moreover, this improved linkage map will enable higher-resolution genetic analyses and catalyze the discovery of the genetic basis for cave-associated phenotypes.
Stress engineering using AlN/GaN superlattices for epitaxy of GaN on 200 mm Si wafers
Authors: Su Jie , Armour Eric A. , Krishnan Balakrishnan , Lee Soo Min , Papasouliotis George D. 
Published: December 2014

ABSTRACTStress control using AlN/GaN superlattices (SLs) for epitaxy of GaN on 200 mm Si (111) substrates is reported. Crack-free 2 μm GaN layers were grown over structures containing 50 to 100 pairs of 3-5 nm AlN/10-30 nm GaN SLs. Compressive and tensile stress can be precisely adjusted by changing the thickness of the AlN and GaN layers in the SLs. For a constant period thickness, the effects of growth conditions, such as growth rate of GaN, V/III ratio during AlN growth, and growth temperature, on wafer stress were investigated.
Randomized Trial of Two Dissemination Strategies for a Skin Cancer Prevention Program in Aquatic Settings
Authors: Glanz Karen , Escoffery Cam , Elliott Tom , Nehl Eric J. 
Published: December 2014

Objectives. We compared 2 strategies for disseminating an evidence-based skin cancer prevention program. Methods. We evaluated the effects of 2 strategies (basic vs enhanced) for dissemination of the Pool Cool skin cancer prevention program in outdoor swimming pools on (1) program implementation, maintenance, and sustainability and (2) improvements in organizational and environmental supports for sun protection. The trial used a cluster-randomized design with pools as the unit of intervention and outcome. The enhanced group received extra incentives, reinforcement, feedback, and skill-building guidance. Surveys were collected in successive years (2003–2006) from managers of 435 pools in 33 metropolitan areas across the United States participating in the Pool Cool Diffusion Trial. Results. Both treatment groups improved their implementation of the program, but pools in the enhanced condition had significantly greater overall maintenance of the program over 3 summers of participation. Furthermore, pools in the enhanced condition established and maintained significantly greater sun-safety policies and supportive environments over time. Conclusions. This study found that more intensive, theory-driven dissemination strategies can significantly enhance program implementation and maintenance of health-promoting environmental and policy changes. Future research is warranted through longitudinal follow-up to examine sustainability.
The Role of Stigma and Medical Mistrust in the Routine Health Care Engagement of Black Men Who Have Sex With Men
Authors: Eaton Lisa A. , Driffin Daniel D. , Kegler Christopher , Smith Harlan , Conway-Washington Christopher , White Denise , Cherry Chauncey 
Published: December 2014

Objectives. We assessed how health care–related stigma, global medical mistrust, and personal trust in one’s health care provider relate to engaging in medical care among Black men who have sex with men (MSM). Methods. In 2012, we surveyed 544 Black MSM attending a community event. We completed generalized linear modeling and mediation analyses in 2013. Results. Twenty-nine percent of participants reported experiencing racial and sexual orientation stigma from heath care providers and 48% reported mistrust of medical establishments. We found that, among HIV-negative Black MSM, those who experienced greater stigma and global medical mistrust had longer gaps in time since their last medical exam. Furthermore, global medical mistrust mediated the relationship between stigma and engagement in care. Among HIV-positive Black MSM, experiencing stigma from health care providers was associated with longer gaps in time since last HIV care appointment. Conclusions. Interventions focusing on health care settings that support the development of greater awareness of stigma and mistrust are urgently needed. Failure to address psychosocial deterrents will stymie progress in biomedical prevention and cripple the ability to implement effective prevention and treatment strategies.
GPR Profiles of Glacial Till and its Transition to Bedrock: Interpretation of Water Content, Depth and Signal Loss from Diffractions
Authors: Arcone Steven , Campbell Seth , Pfeffer W. Tad 
Published: December 2014

We discuss GPR reflection profiles that we recorded on glacial till and a colluvial diamict at several locations in New Hampshire, and from which we interpret water contents, depths and rates of signal loss. We used pulses centered from 150–200 MHz and 300–360 MHz. The boulder-rich sediments reside over granitic and metavolcanics, the horizons of which we recognize from the relative strengths and phase of their waveforms, underlying fractures, and well-developed diffraction asymptotes. The till produced an apparent dense distribution of diffractions with limited asymptotes and dispersion, and occasional minor stratification. We use these diffractions and moveout profiles to calculate relative dielectric permittivities between 17 and 27, values which suggest up to 30% volumetric water, and likely saturation within these over-consolidated sediments. The evidence for transitions from till to bedrock ranges from a simple horizon to complex horizon segments, all characterized by diffractions and amenable to single-layer migration. A gradational loss in diffraction strength with depth suggests gradational weathering or changes in grain size as the cause. Maximum profiled depths range from 4 m to at least 10 m, with estimated scattering attenuation rates of about 3.3 dB m−1. In contrast, one and possible two colluvial diamicts, which likely contained 3-m-size boulders, show short segments of stratification, rare diffraction asymptotes, allow more than 20-m penetration and provide scattering losses of about 0.5 dB m−1. We measured extremely low conductivity and calculated permittivities ranging from 9–12, which suggest high densities and volumetric water content of 4–12%. Low, single scattering loss and deep penetration in the till are consistent with evidence of ground waves traveling up to 40 m one way. The phase polarity of waveforms within till and colluvial events show they may originate from either high or low dielectric contrasts, likely related to water or large boulders, respectively.
Auditor Industry Specialization and Evidence of Cost Efficiencies in Homogenous Industries
Authors: Bills Kenneth L. , Jeter Debra C. , Stein Sarah E. 
Published: December 2014

ABSTRACT
This study examines the audit pricing effects when auditors specialize in industries conducive to transferable audit processes. Our results indicate that industry specialists charge incrementally lower fees in industries with homogenous operations, and particularly in industries with both homogenous operations and complex accounting practices. Moreover, we discover that audit quality is no lower for clients audited by these specialists offering fee discounts, consistent with a conclusion that the reduction in fees indicates cost efficiencies rather than lower-quality audits. Further analysis indicates that the shared economies of scale only occur in a subsample of client firms with relatively high bargaining power. When considered in conjunction with prior research using a survivorship approach, our study provides evidence that certain industries lend themselves to specialization because auditors generate cost-based competitive advantages without compromising service quality.
Data Availability: Data are publicly available from the sources identified in the paper.
Comparative Study of Glucose Homeostasis, Lipids and Lipoproteins, HDL Functionality, and Cardiometabolic Parameters in Modestly Severely Obese African Americans and White Americans With Prediabetes: Implications for the Metabolic Paradoxes
Authors: Healy Sara J. , Osei Kwame , Gaillard Trudy 
Published: December 2014

OBJECTIVE
To determine whether modestly severe obesity modifies glucose homeostasis, levels of cardiometabolic markers, and HDL function in African Americans (AAs) and white Americans (WAs) with prediabetes.

RESEARCH DESIGN AND METHODS
We studied 145 subjects with prediabetes (N = 61 WAs, N = 84 AAs, mean age 46.5 ± 11.2 years, mean BMI 37.8 ± 6.3 kg/m2). We measured fasting levels of lipids, lipoproteins, and an inflammatory marker (C-reactive protein [CRP]); HDL functionality (i.e., levels of paraoxonase 1 [PON1]); and levels of oxidized LDL, adiponectin, and interleukin-6 (IL-6). We measured serum levels of glucose, insulin, and C-peptide during an oral glucose tolerance test. Values for insulin sensitivity index (Si), glucose effectiveness index (Sg), glucose effectiveness at zero insulin (GEZI), and acute insulin response to glucose (AIRg) were derived using a frequently sampled intravenous glucose tolerance test (using MINMOD software).

RESULTS
Mean levels of fasting and incremental serum glucose, insulin, and C-peptide tended to be higher in WAs versus AAs. The mean Si was not different in WAs versus AAs (2.6 ± 2.3 vs. 2.9 ± 3.0 × 10−4 × min−1 [μU/mL]−1). Mean values for AIRg and disposition index as well as Sg and GEZI were lower in WAs than AAs. WAs had higher serum triglyceride levels than AAs (116.1 ± 55.5 vs. 82.7 ± 44.2 mg/dL, P = 0.0002). Mean levels of apolipoprotein (apo) A1, HDL cholesterol, PON1, oxidized LDL, CRP, adiponectin, and IL-6 were not significantly different in obese AAs versus WAs with prediabetes.

CONCLUSIONS
Modestly severe obesity attenuated the ethnic differences in Si, but not in Sg and triglyceride levels in WAs and AAs with prediabetes. Despite the lower Si and PON1 values, AAs preserved paradoxical relationships between the Si and HDL/apoA1/triglyceride ratios. We conclude that modestly severe obesity has differential effects on the pathogenic mechanisms underlying glucose homeostasis and atherogenesis in obese AAs and WAs with prediabetes.
Modeling of the Propagation of Methane from the Longwall Goaf, Performed by Means of a Two-Dimensional Description
Authors: Krawczyk Jerzy , Janus Jakub 
Published: December 2014

Abstract
The paper presents results of a research on the migration of methane from goaf into an area of a longwall ventilated by means of the U-type ventilation system. Two-dimensional models of the area in question were prepared. The models encompassed longwalls whose length was 240 m, as well as segments of the main and tailgate whose length was minimum 50 m. The geometry of the models took into account the details that could make three-dimensional models too complex. These details include: the ribs of the arch support of the headings, frictional and hydraulic props, and the ribs of a section of the longwall powered roof support. Additionally, the presence of gaps between the support sections, by means of which an exchange of gases between the longwall and the adjacent goaf could take place - was taken into consideration. Using the 2D description method, an analysis of the flow of air in the area was carried out. The simulation results were shown as profiles of velocity and streamlines in surrounding of intersections of longwall. with main and tailgate Then, the grid depenadncy of numerical solutions was investigated. This was done by comparing results for three grid densities. The process of methane propagation was simulated for shearer located at two-thirds of the longwall length. The fields of methane concentrations for a steady inflow from goaf were calculated. Subsequently, the effects of a sudden inflow of methane along a segment comprising ten recently advanced roof support sections were computed. The results were presented as a sequence of concentration distributions for selected simulation moments.
Safe Vibrations of Spilling Basin Explosions at “Gotvand Olya Dam” Using Artificial Neural Network
Authors: Bakhshandeh Amnieh Hassan , Bahadori Moein 
Published: December 2014

Abstract
Ground vibration is an undesirable outcome of an explosion which can have destructive effects on the surrounding environment and structures. Peak Particle Velocity (PPV) is a determining factor in evaluation of the damage caused by an explosion. To predict the ground vibration caused by blasting at the Gotvand Olya Dam (GOD) spilling basin, thirty 3-component records (totally 90) from 19 blasts were obtained using 3 VIBROLOC seismographs. Minimum and the maximum distance from the center of the exploding block to the recording station were set to be 11 and 244 meters, respectively. To evaluate allowable safe vibration and determining the permissible explosive charge weight, Artificial Neural Networks (ANN) was employed with Back Propagation (BP) and 3 hidden layers. The mean square error and the correlation coefficient of the network in this study were found to be 1.95 and 0.995, respectively, which compared to those obtained from the known empirical correlations, indicating substantially more accurate prediction. Considering the network high accuracy and precision in predicting vibrations caused by such blasting operations, the nearest distance from the center of the exploding block at this study was 11 m, and considering the standard allowable vibration of 120 mm/sec for heavy concrete structures, the maximum permissible explosive weight per delay was estimated to be 47.00 Kg. These results could be employed in subsequent safer blasting operation designs.
Evaluation and Management of the Gas and Rock Outburst Hazard in the Light of International Legal Regulations
Authors: Skoczylas Norbert , Wierzbicki Mirosław 
Published: December 2014

Abstract
As part of the present article, the Authors analyzed relevant legal rules that are in force in countries where the gas and coal outburst hazard occurs (Australia, the Czech Republic, China, Germany, Poland, Russia, and Ukraine). Similarities and differences between particular solutions were highlighted. As the subject of the analysis were the original legal standards, the article incorporates the parameter symbols and units adopted in the discussed regulations.