bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cometary Materials Originating from Interstellar Ices: Clues from Laboratory Experiments
Authors: Fresneau A. , Mrad N. Abou , LS d’Hendecourt L. , Duvernay F. , Flandinet L. , Orthous-Daunay F.-R. , Vuitton V. , Thissen R. , Chiavassa T. , Danger G. 
Published: March 2017

Abstract
We use laboratory experiments to derive information on the chemistry occurring during the evolution of astrophysical ices from dense molecular clouds to interplanetary objects. Through a new strategy that consists of coupling very high resolution mass spectrometry and infrared spectroscopy (FT-IR), we investigate the molecular content of the organic residues synthesized from different initial ice compositions. We also obtain information on the evolution of the soluble part of the residues after their over-irradiation. The results give insight into the role of water ice as a trapping and diluting agent during the chemical evolution. They also give information about the importance of the amount of ammonia in such ices, particularly regarding its competition with the carbon chemistry. All of these results allow us to build a first mapping of the evolution of soluble organic matter based on its chemical and physical history. Furthermore, our results suggest that interstellar ices should lead to organic materials enriched in heteroatoms that present similarities with cometary materials but strongly differ from meteoritic organic material, especially in their C/N ratios.
SPIRITS 15c and SPIRITS 14buu: Two Obscured Supernovae in the Nearby Star-forming Galaxy IC 2163
Authors: Jencson Jacob E. , Kasliwal Mansi M. , Johansson Joel , Contreras Carlos , Castellón Sergio , Bond Howard E. , Monson Andrew J. , Masci Frank J. , Cody Ann Marie , Andrews Jennifer E. , Bally John , Cao Yi , Fox Ori D. , Gburek Timothy , Gehrz Robert D. , Green Wayne , Helou George , Hsiao Eric , Morrell Nidia , Phillips Mark , Prince Thomas A. , Simcoe Robert A. , Smith Nathan , Tinyanont Samaporn , Williams Robert 
Published: March 2017

Abstract
SPitzer InfraRed Intensive Transients Survey—SPIRITS—is an ongoing survey of nearby galaxies searching for infrared (IR) transients with Spitzer/IRAC. We present the discovery and follow-up observations of one of our most luminous (M
[4.5] = −17.1 ± 0.4 mag, Vega) and reddest ([3.6] − [4.5] = 3.0 ± 0.2 mag) transients, SPIRITS 15c. The transient was detected in a dusty spiral arm of IC 2163 (D ≈ 35.5 Mpc). Pre-discovery ground-based imaging revealed an associated, shorter-duration transient in the optical and near-IR (NIR). NIR spectroscopy showed a broad (≈8400 km s−1), double-peaked emission line of He i at 1.083 μm, indicating an explosive origin. The NIR spectrum of SPIRITS 15c is similar to that of the Type IIb SN 2011dh at a phase of ≈200 days. Assuming an A

V
= 2.2 mag of extinction in SPIRITS 15c provides a good match between their optical light curves. The NIR light curves, however, show some minor discrepancies when compared with SN 2011dh, and the extreme [3.6]–[4.5] color has not been previously observed for any SN IIb. Another luminous (M
4.5 = −16.1 ± 0.4 mag) event, SPIRITS 14buu, was serendipitously discovered in the same galaxy. The source displays an optical plateau lasting ≳80 days, and we suggest a scenario similar to the low-luminosity Type IIP SN 2005cs obscured by A

V
≈ 1.5 mag. Other classes of IR-luminous transients can likely be ruled out in both cases. If both events are indeed SNe, this may suggest that ≳18% of nearby core-collapse SNe are missed by currently operating optical surveys.
On Weibull's Spectrum of Nonrelativistic Energetic Particles at IP Shocks: Observations and Theoretical Interpretation
Authors: Pallocchia G. , Laurenza M. , Consolini G. 
Published: March 2017

Abstract
Some interplanetary shocks are associated with short-term and sharp particle flux enhancements near the shock front. Such intensity enhancements, known as shock-spike events (SSEs), represent a class of relatively energetic phenomena as they may extend to energies of some tens of MeV or even beyond. Here we present an SSE case study in order to shed light on the nature of the particle acceleration involved in this kind of event. Our observations refer to an SSE registered on 2011 October 3 at 22:23 UT, by STEREO B instrumentation when, at a heliocentric distance of 1.08 au, the spacecraft was swept by a perpendicular shock moving away from the Sun. The main finding from the data analysis is that a Weibull distribution represents a good fitting function to the measured particle spectrum over the energy range from 0.1 to 30 MeV. To interpret such an observational result, we provide a theoretical derivation of the Weibull spectrum in the framework of the acceleration by “killed” stochastic processes exhibiting power-law growth in time of the velocity expectation, such as the classical Fermi process. We find an overall coherence between the experimental values of the Weibull spectrum parameters and their physical meaning within the above scenario. Hence, our approach based on the Weibull distribution proves to be useful for understanding SSEs. With regard to the present event, we also provide an alternative explanation of the Weibull spectrum in terms of shock-surfing acceleration.
Microscope-Integrated OCT Feasibility and Utility With the EnFocus System in the DISCOVER Study
Authors: Runkle Anne , Srivastava Sunil K. , Ehlers Justis P. 
Published: March 2017

BACKGROUND AND OBJECTIVE:
To evaluate the feasibility and utility of a novel microscope-integrated intraoperative optical coherence tomography (OCT) system.

PATIENTS AND METHODS:
The DISCOVER study is an investigational device study evaluating microscope-integrated intraoperative OCT systems for ophthalmic surgery. This report focuses on subjects imaged with the EnFocus prototype system (Leica Microsystems/Bioptigen, Morrisville, NC). OCT was performed at surgeon-directed milestones. Surgeons completed a questionnaire after each case to evaluate the impact of OCT on intraoperative management.

RESULTS:
Fifty eyes underwent imaging with the EnFocus system. Successful imaging was obtained in 46 of 50 eyes (92%). In eight cases (16%), surgical management was changed based on intraoperative OCT findings. In membrane peeling procedures, intraoperative OCT findings were discordant from the surgeon's initial impression in seven of 20 cases (35%).

CONCLUSION:

This study demonstrates the feasibility of microscope-integrated intraoperative OCT using the Bioptigen EnFocus system. Intraoperative OCT may provide surgeons with additional information that may influence surgical decision-making.

[
Ophthalmic Surg Lasers Imaging Retina.
2017;48:216–222.]
Divided differences in noncommutative geometry: Rearrangement Lemma, functional calculus and expansional formula
Authors: Lesch Matthias 
Published: March 2017

We state a generalization of the Connes–Tretkoff–Moscovici Rearrangement Lemma and give a surprisingly simple (almost trivial) proof of it. Secondly, we put on a firm ground the multivariable functional calculus used implicitly in the Rearrangement Lemma and elsewhere in the recent modular curvature paper by Connes and Moscovici [3]. Furthermore, we show that the fantastic formulas connecting the one and two variable modular functions of loc. cit. are just examples of the plenty recursion formulas which can be derived from the calculus of divided differences. We show that the functions derived from the main integral occurring in the Rearrangement Lemma can be expressed in terms of divided differences of the Logarithm, generalizing the “modified Logarithm” of Connes–Tretkoff [4].
Finally, we show that several expansion formulas related to the Magnus expansion [13] have a conceptual explanation in terms of a multivariable functional calculus applied to divided differences.
Preoperative computer simulation for planning of vascular access surgery in hemodialysis patients
Authors: Zonnebeld Niek , Huberts Wouter , van Loon Magda M. , Delhaas Tammo , Tordoir Jan H.M. 
Published: March 2017

Introduction The arteriovenous fistula (AVF) is the preferred vascular access for hemodialysis patients. Unfortunately, 20-40% of all constructed AVFs fail to mature (FTM), and are therefore not usable for hemodialysis. AVF maturation importantly depends on postoperative blood volume flow. Predicting patient-specific immediate postoperative flow could therefore support surgical planning. A computational model predicting blood volume flow is available, but the effect of blood flow predictions on the clinical endpoint of maturation (at least 500 mL/min blood volume flow, diameter of the venous cannulation segment ≥4 mm) remains undetermined. Methods A multicenter randomized clinical trial will be conducted in which 372 patients will be randomized (1:1 allocation ratio) between conventional healthcare and computational model-aided decision making. All patients are extensively examined using duplex ultrasonography (DUS) during preoperative assessment (12 venous and 11 arterial diameter measurements; 3 arterial volume flow measurements). The computational model will predict patient-specific immediate postoperative blood volume flows based on this DUS examination. Using these predictions, the preferred AVF configuration is recommended for the individual patient (radiocephalic, brachiocephalic, or brachiobasilic). The primary endpoint is FTM rate at six weeks in both groups, secondary endpoints include AVF functionality and patency rates at 6 and 12 months postoperatively. Trial registration ClinicalTrials.gov (NCT02453412), and ToetsingOnline.nl (NL51610.068.14).
Improvement of radiocephalic fistula maturation: rationale and design of the Liposomal Prednisolone to Improve Hemodialysis Fistula Maturation (LIPMAT) study – a randomized controlled trial
Authors: Voorzaat Bram M. , van Schaik Jan , van der Bogt Koen E.A. , Vogt Liffert , Huisman Laurens , Gabreëls Bas A. Th. F. , van der Meer Irene M. , van Eps Randolph G.S. , Eefting Daniël , Weijmer Marcel C. , Groeneveld Han O. , van Nieuwenhuizen Roos C. , Boom Henk , Verburgh Cornelis A. , van der Putten Karien , Rotmans Joris I. 
Published: March 2017

Background Non-maturation is a frequent complication of radiocephalic arteriovenous fistulas (RCAVF). In an animal model, liposomal prednisolone improved maturation of experimental fistulas. The Liposomal Prednisolone to Improve Hemodialysis Fistula Maturation (LIPMAT) study investigates if liposomal prednisolone improves RCAVF maturation. Methods and results The LIPMAT study is an investigator-initiated, multicenter, double-blinded, placebo-controlled randomized controlled trial with 1:1 randomization to liposomal prednisolone or placebo. Eighty patients receiving an RCAVF will be included. The primary outcome is the cephalic vein diameter six weeks after surgery, measured by ultrasound. The LIPMAT study started in May 2016. Enrollment is expected to be completed by the end of 2017. Conclusions The LIPMAT study is the first to evaluate the efficacy of liposomal prednisolone to enhance RCAVF maturation.
Upper-arm hemodialysis access in Sweden
Authors: Hedin Ulf , Welander Gunilla 
Published: March 2017

Aim To provide the contemporary use of upper-arm access for hemodialysis in Sweden using data from a unique national registry for hemodialysis access. Methods Data were retrieved from a nation-wide registry for dialysis access in Sweden, Dialysis Access Database (DiAD) on the use and function of specific access types with a focus on upper-arm accesses. Results The data demonstrate an increased use of upper-arm access, likely dependent on a changing patient population, with brachiocephalic arteriovenous fistula (AVF) as the most common access type. Women received more upper-arm accesses than men. Given the recent establishment of the registry, patency and access function can at this point give preliminary data. Indications of a better function for brachiobasilic AVFs in staged procedures were observed as well as for upper-arm arteriovenous grafts (AVGs) in women. Conclusions Registry data support an increased use of upper-arm accesses, especially in women. The study also demonstrates the potential of a dedicated national access registry to improve access care.
Elbow AVF configurations and indications
Authors: Baktiroglu Selcuk , Yanar Fatih , Yuksel Sercan , Celik Burak , Kilic Halime G. 
Published: March 2017

Introduction Brescia-Cimino radiocephalic arteriovenous fistula (AVF) remains the first-choice vascular access procedure for patients in need of long-term hemodialysis. The average life expectancy of patients receiving hemodialysis has increased in recent years and many patients now live longer and require secondary or tertiary procedures. Elbow fistulas should only rarely be constructed as primary fistulas. The aim of the surgeon must be not only to achieve a functioning fistula, but to avoid possible complications other than failure to mature (FTM), like distal ischemia and cardiac failure and to save the vessels as much as possible for future procedures Background Both arterial and venous anatomy of the elbow and upper arm have significant variations. The surgeon must be aware of these variations during the operation, and try not to harm the vasculature of the extremity while trying to construct a functioning fistula. The main advantages of elbow fistulas are the opportunity to have multiple outflows, preservation of the major veins in their original place with no dissection and giving no harm to them, and having a longer outflow tract for cannulation. Conclusions In the elbow, beginning to construct an AVF with the perforating vein is the most advantageous. If the perforating vein is not available or has been used before, median cubital vein, its branches, median antecubital vein or other available nearby veins may be used depending on the anatomy. Perforating vein should be ligated if any other elbow vein is used to prevent flow to deep veins.
Factors related to patient selection and initiation of peritoneal dialysis
Authors: Wasse Haimanot 
Published: March 2017

The majority of dialysis patients initiate dialysis using hemodialysis, rather than peritoneal dialysis (PD), although they may be candidates for either modality. Multiple factors account for this selection, including pre-dialysis education, physician familiarity with hemodialysis versus PD, and patient-related factors. This paper will discuss the various considerations by both providers and patients in the selection of PD as a modality.
Between a rock and a hard place: The reasons why women delay childbearing
Authors: Daniluk Judith C , Koert Emily 
Published: March 2017

The increasing trend for women to delay childbearing is often met with harsh criticism and judgment, based on the assumption that women are prioritizing their careers over having children. An on-line survey of 500 currently childless Canadian women between the ages of 18 and 38 (M = 28) assessed participants’ childbearing intentions and beliefs, and the factors they felt were most important in the timing of childbearing. Although the respondents felt women should ideally have their first child in their late 20s, most expected that they would begin their families in their 30s. The ability to financially support a child was the most strongly endorsed factor in the timing of childbearing, followed by good health, being with a partner who would be an involved and loving parent, and having a proper home in which to raise a child. These findings highlight the values and beliefs that were most salient in participants’ decisions about the timing of childbearing.
Disclosure of sexual orientation to health professionals in China: results from an online cross‐sectional study
Authors: Tang Weiming , Mao Jessica , Tang Songyuan , Liu Chuncheng , Mollan Katie , Cao Bolin , Wong Terrence , Zhang Ye , Hudgens Michael , Qin Yilu , Han Larry , Ma Baoli , Yang Bin , Ma Wei , Wei Chongyi , Tucker Joseph D ,   Group SESH Study
Published: March 2017

AbstractBackground: Many men who have sex with men (MSM) in China are “in the closet.” The low rate of disclosure may impact sexual behaviours, testing for HIV and other sexually transmitted infections (STIs), and diseases transmission. This study examines factors associated with overall sexual orientation disclosure and disclosure to healthcare professionals.Methods: A nationwide cross‐sectional online survey was conducted from September 2014 to October 2014 in China. Participants completed questions covering socio‐demographic information, sexual behaviours, HIV/STI testing history, and self‐reported HIV status. We defined healthcare professional disclosure as disclosing to a doctor or other medical provider.Results: A total of 1819 men started the survey and 1424 (78.3%) completed it. Among the 1424 participants, 62.2% (886/1424) reported overall disclosure, and 16.3% (232/1424) disclosed to healthcare professionals. In multivariate analyses, the odds of sexual orientation disclosure were 56% higher among MSM who used smartphone‐based, sex‐seeking applications [adjusted odds ratio (aOR) = 1.56, 95% CI: 1.25–2.95], but were lower among MSM reporting sex while drunk or recreational drug use. The odds of disclosure to a healthcare professional were greater among MSM who had ever tested for HIV or STIs (aOR = 3.36, 95% CI: 2.50–4.51 for HIV, and aOR = 4.92, 95% CI: 3.47–6.96 for STIs, respectively) or self‐reported as living with HIV (aOR = 1.59, 95% CI: 0.93–2.72).Conclusion: Over 80% of MSM had not disclosed their sexual orientation to health professionals. This low level of disclosure likely represents a major obstacle to serving the unique needs of MSM in clinical settings. Further research and interventions to facilitate MSM sexual orientation disclosure, especially to health professionals, are urgently needed.
Atmospheric Chemistry
Authors: Stockwell William R. 
Published: March 2017

AbstractThe Earth's atmosphere is composed of several layers each one has its distinct chemistry. Major environmental problems involving atmospheric chemistry include air pollution, acid rain, stratospheric ozone depletion, and climate change.The article describes the atmosphere layers, related atmospheric chemistry reactions, and the role of photochemistry as their driver. Air quality models that provide a powerful framework for understanding the dynamics of pollutants in the atmosphere and for assessing the impact emission sources have on pollutant concentrations are discussed.
Photovoltaic Cells
Authors: Wohlgemuth John 
Published: March 2017

Abstract
Photovoltaic cells, or solar cells, are solid‐state devices that convert light into electricity via the photovoltaic effect. Solar cells are utilized to convert sunlight into direct current (dc) electricity, which can be used to operate DC loads, charge batteries, or to run an inverter that turns DC into alternating current (AC) to directly power AC appliances or to feed electricity into the utility grid.Starting with the Vanguard satellite in the 1950s, photovoltaic (PV) cells have been utilized to power many space satellites. In the 1970s, PV was recognized as an excellent power source for remote sites, leading to the development of the terrestrial PV industry. In the 1990s, national programs in Japan and Germany moved PV into grid‐connected applications. Today, large‐scale implementation of PV includes utility scale systems, large commercial systems on such businesses as Walmart and Kohl's, and large numbers of smaller residential sized systems. In 2015, PV systems made up 28% of all new electricity supply in the world.
Raman Scattering
Authors: Smith W. Ewen 
Published: March 2017

AbstractRaman scattering involves the detection of inelastic light scattering resulting from molecular vibrations. Sharp clear vibrational spectra can be obtained when a sample is irradiated with monochromatic radiation. Modern equipment developments have made Raman scattering much simpler to collect with the result that the field has grown considerably recently.This article outlines the basic theory and shows how vibrational assignments are made from the data. A brief description of the factors to consider in setting up or purchasing an instrument is given, and two methods that arise from Raman scattering, resonance Raman scattering, and surface‐enhanced Raman scattering are introduced.
Research and Development Management
Authors: Sapienza Alice M. 
Published: March 2017

Abstract
This article highlights the responsibility of those in a leadership role in supporting the innovative and beneficial output of scientists in research and development (R&D).
The article begins by providing an overview of the global context in which R&D take place and the turbulence and complexity that characterize this environment. It then characterizes R&D professionals and discusses implications for those leading them, particularly challenges to creative and productive endeavors. Science and technology strategy of R&D programs and projects, with an emphasis on consistency and competitiveness and the potential effects on the professionals involved, are discussed next. The article concludes with a brief review on managing work and personal life stressors.
Solar Energy Materials For Thermal Applications
Authors: Granqvist Claes G. 
Published: March 2017

AbstractSolar energy materials for thermal applications have properties tailored to meet requirements set by the spectral distribution, angle of incidence, and intensity of the electromagnetic radiation prevailing in our natural surroundings. Specifically, the optimization can be performed with regard to solar irradiation, thermal emission, atmospheric absorption, visible light, and photosynthetic efficiency. The materials may be metals, glasses, polymers, gases, paints and, especially, thin surface coatings of many kinds. Discussions are given on a number of specific topics such as transparent thermal insulation, solar thermal converters, radiative cooling, as well as windows and glass facades with static or dynamic properties.
Acid–Base and Solvation properties of Metal Enolates. Part 1: The Enolate Ion and Main‐Group Metal Enolates
Authors: Bastos Erick L. 
Published: March 2017

Abstract
This chapter presents an overview of the fundamental aspects of the formation and structure of metal enolates, focusing on the consequences of acid–base and solvation properties of main‐group metal enolates on their chemical reactivity. Reference data such as equilibrium and acid dissociation constants are compiled.
Perovskite Materials: Solar Cell and Optoelectronic Applications
Authors: Yang Bin , Geohegan David B. , Xiao Kai 
Published: March 2017

Abstract
Hybrid organometallic trihalide perovskites are promising candidates in the applications for next‐generation, high‐performance, low‐cost optoelectronic devices, including photovoltaics, light‐emitting diodes, and photodetectors. In particular, the solar cells based on this type of materials have reached 22% lab‐scale power conversion efficiency in only about 7 years, comparable to the other thin‐film photovoltaic technologies. Hybrid perovskite materials not only exhibit superior optoelectronic properties but also show many interesting physical properties such as ion migration and defect physics, which may allow the exploration of more device functionalities. In this article, the fundamental understanding of the interrelationships between crystal structure, electronic structure, and material properties is discussed. Various chemical synthesis and processing methods for superior device performance in solar cells and optoelectronic devices are reviewed.