bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Construction of X–CN (X=N, S, O) Bonds
Authors: Yu Jin‐Tao , Teng Fan , Cheng Jiang 
Published: November 2016

AbstractThe cyano moiety is a common and important functional group that exists in a myriad of medicinal molecules and natural products. Moreover, nitriles serve as versatile precursors that can readily be converted into diverse functional groups as well as the nitrogen‐containing cyclic molecules. As a result, cyanation has become a significant type of transformation in organic chemistry. However, in comparison with the well‐developed C‐cyanation, few works have been reported dealing with the N‐, S‐ and O‐cyanation processes. Apart from the classical von Braun reaction, chemists have developed a number of methods with various cyanating reagents to achieve such X‐cyanations (X=N, S, O). In this review, recent advances (especially those after 2000) in the X–CN (X=N, S, O) bond formation are summarized with discussion and the outlooks are also listed.magnified image
Use of Social Media in Emergency Ultrasound Fellowship Programs
Authors: Amini Richard , Wang Janelle B. , Trueger N. Seth , Hoyer Riley , Adhikari Srikar 
Published: November 2016

AbstractObjectiveSocial media has been gaining traction among learners and educators for its ability to stimulate discussion, increase participation, and promote knowledge sharing. Despite the growing research around the benefits of social media in education, there is little evidence on how it is being incorporated into emergency ultrasound (EUS) fellowships. This study aims to determine the preference and use of social media by engaging with program directors across EUS programs in the United States to assess the current landscape of and attitudes toward social media use.MethodsThis was a cross‐sectional study. An online questionnaire was electronically sent to all EUS fellowship directors across the country. The survey consisted of questions regarding current practice patterns, policies, and perceptions regarding the use of social media in EUS fellowship programs.ResultsNinety‐six ultrasound fellowship programs were identified for inclusion into this study. A total of 64 participants completed the survey, representing a 63% response rate. Thirty‐eight percent (95% confidence interval [CI] = 26% – 50%) of responding fellowship programs have an official social media outlet and 25% have a separate ultrasound handle for their EM residency program. Fifty‐eight percent (95% CI = 46% – 70%) of programs do not provide training to fellows and residents on the social media outlets used by their program. The top two social media outlets currently being used by programs are Twitter and YouTube to disseminate educational content and knowledge sharing. Twenty‐eight percent (95% CI = 17% – 39%) of programs create or post new ultrasound content at least once per month. Regarding barriers in the use of social media in EUS fellowships, 57% (95% CI = 45% – 69%) of program directors sited lack of time as the primary reason for decreased usage and implementation. Eighty‐four percent (95% CI = 75% – 93%) of responders felt that social media has the potential to impact patient care.ConclusionsThe results of this study indicate that there is perceived value in utilizing social media resources in EUS education; however, certain challenges need to be further evaluated.
Evaluation of the R2D2 protocol: A Novel Method for Assessing Emergency Department Disposition for Residents
Authors: Hernandez Jesse , Corker John , Roppolo Lynn , Jones Kyle , Hsu Daniel , Arthur D'Ann Elizabeth , Hynan Linda 
Published: November 2016

AbstractBackgroundThe emergency department (ED) disposition and discharge process is a critical period in a patient's transition from an acute care setting to self‐care or a bridge to other healthcare providers. The emergency physician plays a pivotal role in this process and is ultimately responsible for ensuring that patients are safely released from their care. We developed a protocol to guide residents through the ED discharge process using the mnemonic “R2D2”: reassess the patient, recheck the workup, discuss the disposition plan with the attending, and finally discuss the discharge plan with the patient.ObjectivesThe objective was to assess the effectiveness of the R2D2 discharge protocol, executed by resident physicians, in improving patients' understanding of their diagnosis and treatment plans.MethodsThis is a before‐and‐after study in the ED of a county hospital and included all patients discharged by a resident physician from the ED 1 week before and 1 week after implementation of the R2D2 protocol. All participating resident physicians received a brief 10‐minute orientation to the R2D2 protocol at the end of the first week of the study period. Consecutive patients were identified, consented, and given a brief questionnaire about their discharge by research assistants. Certain exclusion criteria applied such as inability to speak English or Spanish or no phone for follow‐up. One to 2 weeks after ED discharge, patients from both groups were contacted by phone to assess their recall of their discharge instructions. Data analyses were performed using Fisher's exact, chi‐square tests, or two independent‐sample proportions tests as appropriate.ResultsWe recruited 164 patients in the control group and 148 patients in the intervention group, totaling 312 patients. A total of 73.8% of the control group patients and 77.0% of the intervention group patients completed the follow‐up. On telephone follow‐up, 88% of the intervention patients knew their discharge diagnosis versus only 74% of control patients (p = 0.0062). Eighty percent of intervention patients knew their discharge treatment plan versus only 67% of control patients (p = 0.0259).ConclusionsThe R2D2 protocol resulted in significant improvement in patients' understanding of their discharge diagnosis and treatment plan.
Making the McMOST out of Milestones and Objectives: Reimagining Standard Setting Using the McMaster Milestones and Objectives Stratification Technique
Authors: Chan Teresa M. , Baw Bandar , McConnell Meghan , Kulasegaram Kulamakan 
Published: November 2016

AbstractBackgroundAs we enter the era of milestones and competency‐based medical education (CBME), there is an increasing need to examine the procedures for stratifying objectives into levels of achievement. Most techniques used to date (e.g., Delphi surveys) involve some sort of consensus‐based process, essentially crowd‐sourcing wisdom of multiple educators to set anticipated milestones. In most graduate education settings, however, many simply use the judgment of one or two educators when setting educational objectives. Meanwhile, standard‐setting procedures have been historically used in medical education for setting cut‐points to determine levels of acceptable performance and do so in a more robust manner.ObjectivesInspired by these standard‐setting procedures, the authors sought to develop a new way to stratify objectives into three relative levels of achievement (junior [ACGME level 1], intermediate [ACGME level 2–3], senior [ACGME level 4]).MethodsThe authors describe a novel, stepwise method that is composed of four steps. There are four steps to the McMOST procedure: 1) sorting objectives with a group of experienced teachers, 2) factor analysis to group preferences, 3) labeling components and reorganizing groupings, and 4) confirmation and final review by educational and content experts.ResultsUsing McMOST method resulted in a change of placement for 15 of 34 (44%) of the milestones and improved agreement in two of three levels (intermediate from intraclass correlation of 0.56 to 0.80; senior from 0.69 to 0.79).ConclusionsThe authors describe a novel protocol for stratifying objectives that may be useful to stratify and sort competencies into various levels of achievement (e.g., milestones) in this era of CBME.
Management of maternal anaphylaxis in pregnancy: a case report
Authors: Tsuzuki Yasunobu , Narita Mitsuo , Nawa Masayuki , Nakagawa Urara , Wakai Toshiaki 
Published: November 2016

CaseA 26‐year‐old woman (gravida 2, para 1) at 25 weeks’ gestation was brought to the emergency department because of anaphylactic symptoms. She reported eating Japanese soba and developed symptoms of dyspnea, generalized itchy rash, abdominal pain, and severe uterine contractions within 15–30 min of eating. She was immediately treated by normal saline infusion, two injections of epinephrine (intramuscularly), and a nebulized short‐acting β2‐receptor agonist, followed by H1‐antihistamine and methylprednisolone. Obstetrical management was undertaken by an obstetrician.OutcomeThe patient recovered rapidly without a biphasic reaction of anaphylaxis. After 11 weeks, a healthy, neurologically intact baby was born.ConclusionManagement of anaphylaxis in pregnant patients is basically the same of that in non‐pregnant ones. Treatment should commence immediately to prevent further development of the anaphylaxis reaction and fetal neurological deficiency.
Non‐traumatic bladder rupture showing less than 10 Hounsfield units of ascites
Authors: Mizumura Naoto , Okumura Satoshi , Toyoda Sho , Imagawa Atsuo , Ogawa Masao , Kawasaki Masayasu 
Published: November 2016

AimBladder ruptures are commonly misdiagnosed as gastrointestinal perforations or intestinal ischemia. If a diagnosis is made preoperatively, conservative treatment is a safe and effective option. We evaluated the validity of using the attenuation value of ascites, measured by non‐contrast computed tomography (CT), to identify patients with bladder ruptures.MethodsA retrospective search of our hospital database identified 7 patients with confirmed bladder ruptures between 2007 and 2013. We also enrolled 18 patients with gastrointestinal perforations and 10 patients with intestinal ischemia with detectable ascites on abdominal CT that had undergone emergency exploratory laparotomy between 2007 and 2013. Between‐group comparisons of attenuation values of ascites as obtained by non‐contrast CT were evaluated.ResultsAll attenuation values were less than 10 Hounsfield units (HU) in bladder rupture patients. Moreover, the attenuation value of ascites in cases of bladder rupture (median, 5.7; range, 3.1–6.1) was significantly lower than in cases of gastrointestinal perforation (median, 14.7; range, 4.7–25.4) and intestinal ischemia (median, 13.3; range, 6.0–18.1) (P = 0.004 for both comparisons).ConclusionBladder rupture mimics gastrointestinal perforation and intestinal ischemia with acute kidney injury. Therefore, the diagnosis of bladder rupture using the attenuation value of ascites on non‐contrast CT is both useful and highly significant. We suggest that bladder rupture be considered in the differential diagnosis of patients presenting with acute abdominal pain and attenuation values of ascites of less than 10 Hounsfield units.
Diagnostic accuracy of radiographs for detecting supraglottitis: a systematic review and meta‐analysis
Authors: Fujiwara Takashi , Miyata Toyohisa , Tokumasu Hironobu , Gemba Hiroko , Fukuoka Toshio 
Published: November 2016

AimTo assess the diagnostic performance of lateral radiograph of the neck for supraglottitis in adults and children.MethodsElectronic database searches (including PubMed, EMBASE, CINAHL, Web of Science, and WHO International Clinical Trials Registry Platform) were carried out through July 2014. Citations of included studies and recent narrative reviews were searched. Studies that compared lateral radiograph of the neck with a reference standard of direct/indirect laryngoscopy were included. Two reviewers independently assessed the methodological quality of included studies by Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS‐2).ResultsOf 2,088 potentially relevant citations, two single‐gate (cohort) studies and six two‐gate (case–control) studies were identified. These included studies of design are at the moderate or high risk of bias in QUADAS‐2. The pooled sensitivity from bivariate random‐effects regression was 92.9% (95% confidence interval [CI], 88.5–95.9%) and the pooled specificity was 89.2% (95% CI, 85.9–91.9%), but the diagnostic value would be overestimated because of selection bias in the six two‐gate studies. The sensitivity and specificity of the single‐gate studies were 100.0% (95% CI, 92.2–100.0%) and 30.6% (95% CI, 15.5–35.6%) in children and 81.0% (95% CI, 78.2–93.2%) and 85.7% specificity (95% CI, 78.2–93.2%) in adults.ConclusionThis study determines that there are insufficient studies of lateral neck radiograph for detecting supraglottitis. Lateral radiograph of the neck seems to have moderate accuracy for detecting supraglottitis. Further approximately unbiased studies are needed to obtain more valid and reliable estimates of test accuracy.
Tuning of Silver Catalyst Mesostructure Promotes Selective Carbon Dioxide Conversion into Fuels
Authors: Yoon Youngmin , Hall Anthony Shoji , Surendranath Yogesh 
Published: November 2016

AbstractAn electrode's performance for catalytic CO2 conversion to fuels is a complex convolution of surface structure and transport effects. Using well‐defined mesostructured silver inverse opal (Ag‐IO) electrodes, it is demonstrated that mesostructure‐induced transport limitations alone serve to increase the turnover frequency for CO2 activation per unit area, while simultaneously improving reaction selectivity. The specific activity for catalyzed CO evolution systematically rises by three‐fold and the specific activity for catalyzed H2 evolution systematically declines by ten‐fold with increasing mesostructural roughness of Ag‐IOs. By exploiting the compounding influence of both of these effects, we demonstrate that mesostructure, rather than surface structure, can be used to tune CO evolution selectivity from less than 5 % to more than 80 %. These results establish electrode mesostructuring as a powerful complementary tool for tuning both catalyst selectivity and efficiency for CO2 conversion into fuels.
Evaporite Borate‐Containing Mineral Ensembles Make Phosphate Available and Regiospecifically Phosphorylate Ribonucleosides: Borate as a Multifaceted Problem Solver in Prebiotic Chemistry
Authors: Kim Hyo‐Joong , Furukawa Yoshihiro , Kakegawa Takeshi , Bita Andrei , Scorei Romulus , Benner Steven A. 
Published: November 2016

AbstractRNA is currently thought to have been the first biopolymer to support Darwinian natural selection on Earth. However, the phosphate esters in RNA and its precursors, and the many sites at which phosphorylation might occur in ribonucleosides under conditions that make it possible, challenge prebiotic chemists. Moreover, free inorganic phosphate may have been scarce on early Earth owing to its sequestration by calcium in the unreactive mineral hydroxyapatite. Herein, it is shown that these problems can be mitigated by a particular geological environment that contains borate, magnesium, sulfate, calcium, and phosphate in evaporite deposits. Actual geological environments, reproduced here, show that Mg2+ and borate sequester phosphate from calcium to form the mineral lüneburgite. Ribonucleosides stabilized by borate mobilize borate and phosphate from lüneburgite, and are then regiospecifically phosphorylated by the mineral. Thus, in addition to guiding carbohydrate pre‐metabolism, borate minerals in evaporite geoorganic contexts offer a solution to the phosphate problem in the “RNA first” model for the origins of life.
Kryo‐Elektronenmikroskopie als Methode für die strukturbasierte Wirkstoffentwicklung
Authors: Merino Felipe , Raunser Stefan 
Published: November 2016

AbstractÜber Jahrzehnte hinweg waren die Röntgenkristallographie und NMR‐Spektroskopie die wichtigsten Techniken, um atomare Strukturen von Makromolekülen zu erforschen. Aufgrund ihrer Größe, Instabilität, niedrigen Ausbeuten und anderen Faktoren sind jedoch viele Makromoleküle schwer zu kristallisieren oder nicht geeignet für NMR‐Studien. Die Kryo‐Elektronenmikroskopie (Kryo‐EM) benötigt keine Kristalle und ist deshalb oft die Methode der Wahl für makromolekulare Komplexe, die nicht kristallisiert werden können. Die Methode litt aber bisher unter der Einschränkung, dass selten atomare Auflösung erreicht wurde. Eine neue Generation von Detektoren, die in der Lage sind, einfallende Elektronen direkt zu messen, hat aber das Gebiet in den vergangenen drei Jahren revolutioniert. Mit dieser Technik gelingt es nun routinemäßig, die Strukturen von Makromolekülen mit nahezu atomarer Auflösung zu bestimmen. In diesem Aufsatz stellen wir einige der jüngsten Beispiele für hochaufgelöste Kryo‐EM‐Strukturen vor. Wir legen den Schwerpunkt auf Proteine mit pharmakologischer Relevanz, deren Strukturen mittels klassischer Kristallographie bisher nicht lösbar waren. Des Weiteren diskutieren wir Beispiele, in denen die Wechselwirkungen von Proteinen mit kleinen Molekülen bei atomarer Auflösung charakterisiert wurden. Abschließend erörtern wir die derzeitigen Grenzen der Kryo‐EM sowie wichtige Aspekte bezüglich ihrer Anwendung als Routine‐Methode für die Wirkstoffentwicklung.
Ketenimines from Isocyanides and Allyl Carbonates: Palladium‐Catalyzed Synthesis of β,γ‐Unsaturated Amides and Tetrazoles
Authors: Qiu Guanyinsheng , Mamboury Mathias , Wang Qian , Zhu Jieping 
Published: November 2016

AbstractThe reaction of allyl ethyl carbonates with isocyanides in the presence of a catalytic amount of Pd(OAc)2 provided ketenimines through β‐hydride elimination of the allyl imidoylpalladium intermediates. The insertion of the isocyanide into the π‐allyl Pd complex proceeded via an unusual η1‐allyl Pd species. The resulting ketenimines were hydrolyzed to β,γ‐unsaturated carboxamides during purification by flash column chromatography on silica gel or converted in situ into 1,5‐disubstituted tetrazoles by [3+2] cycloaddition with hydrazoic acid or trimethylsilyl azide.
Pentafluorethylkieselsäuren
Authors: Schwarze Nico , Steinhauer Simon , Neumann Beate , Stammler Hans‐Georg , Hoge Berthold 
Published: November 2016

AbstractReine, wasserfreie Hexafluorkieselsäure, H2[SiF6], ist immer noch schwer fassbar, obwohl ihre Existenz in wässriger Lösung ausführlich dokumentiert wurde. Beim Einengen entsprechender Lösungen tritt unausweichlich Zersetzung unter Bildung von Tetrafluorsilan und Fluorwasserstoff ein. Auch Oxoniumhexafluorosilicat ist bei Raumtemperatur nicht stabil. Partielle Substitution von Fluoratomen im [SiF6]2−‐Ion durch stark elektronenziehende Perfluoralkylgruppen führt zu einer erheblichen Stabilisierung der entsprechenden Fluorkieselsäure‐Derivate. So wurden mono‐ und bis(pentafluorethyl)substituierte Fluorkieselsäuren durch Umsetzung der zugehörigen Halogensilane (Si(C2F5)nX4−n, mit X=Cl, Br) mit Flusssäure (wässrige HF) synthetisiert und in Form ihrer Oxonium‐Salze als farblose Feststoffe isoliert. Die Präparate sind bei Raumtemperatur mehrere Monate ohne Zersetzung beständig und repräsentieren die ersten stabilen Hydrate von Fluorkieselsäuren.
Phosphor(V)‐nitrid macht pyrotechnische Tarnnebel sicherer
Authors: Koch Ernst‐Christian , Cudziło Stanisław 
Published: November 2016

AbstractDer mögliche Ersatz von rotem Phosphor, PR, durch Phosphor(V)‐nitrid, P3N5, wurde theoretisch und experimentell untersucht. P3N5 kann gefahrlos mit KNO3 und sogar KClO3 sowie KClO4 gemischt werden. Die entsprechenden Formulierungen sind erstaunlicherweise reibunempfindlich und wenig schlagempfindlich. P3N5/KNO3‐Sätze mit ξ=20–80 Gew.‐% P3N5 erzeugen ein dichtes Aerosol und brennen etwa 200‐mal schneller ab als entsprechende Sätze mit PR. Daher haben P3N5/KNO3‐Tarnnebelsätze eine Leistungskennzahl, die diejenige herkömmlicher Tarnnebel auf der Grundlage von PR deutlich übersteigt. Auch ist P3N5 an feuchter Luft stabil und liefert nicht wie PR verschiedene Phosphorsäuren und Phosphan, PH3. P3N5 ist daher ein sicherer, stabiler und leistungsstarker Ersatz für PR zur Verwendung in unempfindlicher Munition.
Rhodium(I)‐Catalyzed C−C Bond Activation of Siloxyvinylcyclopropanes with Diazoesters
Authors: Feng Sheng , Mo Fanyang , Xia Ying , Liu Zhenxing , Liu Zhen , Zhang Yan , Wang Jianbo 
Published: November 2016

AbstractThe rhodium(I)‐catalyzed C−C bond activation reaction of siloxyvinylcyclopropanes with diazoesters demonstrates a novel mode of C−C bond cleavage of siloxyvinvylcyclopanes. The alkene products were obtained as single E‐configured isomers in good yields. A σ,η3‐allyl rhodium complex, which has been previously proposed as the key intermediate in rhodium(I)‐catalyzed cycloaddition of vinylcyclopropanes, has been isolated and characterized by X‐ray crystallography.
Direct Observation of Oxygen Dissociation on Non‐Stoichiometric Metal Oxide Catalysts
Authors: Huang Yi‐Lin , Pellegrinelli Chistopher , Wachsman Eric D. 
Published: November 2016

AbstractOxygen dissociation on metal oxides is a key reaction step, limiting the efficiency of numerous technologies. The complexity of the multi‐step oxygen reduction reaction (ORR) makes it difficult to investigate the oxygen dissociation step independently. Direct observation of the oxygen dissociation process is described, quantitatively, on perovskites La0.6Sr0.4Co0.2Fe0.8O3‐δ and (La0.8Sr0.2)0.95MnO3±δ, using gas‐phase isotope‐exchange with a 1:1 16O2:18O2 ratio. Oxygen transport mechanisms between gas–surface reactions and surface–bulk exchange are deconvoluted. Our findings show that regardless of participation of lattice oxygen, La0.6Sr0.4Co0.2Fe0.8O3‐δ is better at oxygen dissociation than (La0.8Sr0.2)0.95MnO3±δ. Heteroexchange, involving lattice oxygen, dominates on La0.6Sr0.4Co0.2Fe0.8O3‐δ. In contrast, (La0.8Sr0.2)0.95MnO3±δ shows both homoexchange and heteroexchange, with the latter only happening above 600 °C. Using a 1:1 isotope mixture, a simple method is presented for separation of the oxygen dissociation step from the overall ORR.
Chemically Delaminated Free‐Standing Ultrathin Covalent Organic Nanosheets
Authors: Khayum M. Abdul , Kandambeth Sharath , Mitra Shouvik , Nair Sanoop B. , Das Anuja , Nagane Samadhan S. , Mukherjee Rabibrata , Banerjee Rahul 
Published: November 2016

AbstractCovalent organic nanosheets (CONs) are a new class of porous thin two‐dimensional (2D) nanostructures that can be easily designed and functionalized and could be useful for separation applications. Poor dispersion, layer restacking, and difficult postsynthetic modifications are the major hurdles that need to be overcome to fabricate scalable CON thin films. Herein, we present a unique approach for the chemical exfoliation of an anthracene‐based covalent organic framework (COF) to N‐hexylmaleimide‐functionalized CONs, to yield centimeter‐sized free‐standing thin films through layer‐by‐layer CON assembly at the air–water interface. The thin‐layer fabrication technique presented here is simple, scalable, and does not require any surfactants or stabilizing agents.
Identification of Two Distinct Sites for Antagonist and Biased Agonist Binding to the Human Chemokine Receptor CXCR3
Authors: Milanos Lampros , Saleh Noureldin , Kling Ralf C. , Kaindl Jonas , Tschammer Nuska , Clark Timothy 
Published: November 2016

AbstractThe chemokine receptor CXCR3 is a G protein‐coupled receptor that conveys extracellular signals into cells by changing its conformation upon ligand binding. We previously hypothesized that small‐molecule allosteric CXCR3‐agonists do not bind to the same allosteric binding pocket as 8‐azaquinazolinone‐based negative allosteric modulators. We have now performed molecular‐dynamics (MD) simulations with metadynamics enhanced sampling on the CXCR3 system to refine structures and binding modes and to predict the CXCR3‐binding affinities of the biased allosteric agonist FAUC1036 and the negative allosteric modulator RAMX3. We have identified two distinct binding sites; a “shallow” and a second “deeper” pocket to which the biased allosteric agonist FAUC1036 and negative allosteric modulator RAMX3 bind, respectively.