bluuebunny/crossref_metadata_2025 huggingface dataset:
Separation dimension and sparsity
Authors: Alon Noga , Basavaraju Manu , Chandran L. Sunil , Mathew Rogers , Rajendraprasad Deepak
Published: February 2018

The separation dimension of a hypergraph G is the smallest natural number k for which the vertices of G can be embedded in so that any pair of disjoint edges in G can be separated by a hyperplane normal to one of the axes. Equivalently, it is the cardinality of a smallest family of total orders of , such that for any two disjoint edges of G, there exists at least one total order in in which all the vertices in one edge precede those in the other. Separation dimension is a monotone parameter; adding more edges cannot reduce the separation dimension of a hypergraph. In this article, we discuss the influence of separation dimension and edge‐density of a graph on one another. On one hand, we show that the maximum separation dimension of a k‐degenerate graph on n vertices is and that there exists a family of 2‐degenerate graphs with separation dimension . On the other hand, we show that graphs with bounded separation dimension cannot be very dense. Quantitatively, we prove that n‐vertex graphs with separation dimension s have at most edges. We do not believe that this bound is optimal and give a question and a remark on the optimal bound.
The evolution of HIV-1 entry phenotypes as a guide to changing target cells
Authors: Joseph Sarah B , Swanstrom Ronald
Published: February 2018

Through a twist of fate the most common form of HIV-1, as defined by entry phenotype, was not appreciated until recently. The entry phenotype is closely linked to the target cell and thus to virus–host interactions and pathogenesis. The most abundant form of HIV-1 uses CCR5 as the coreceptor and requires a high density of CD4 for efficient entry, defining its target cell as the CD4+ memory T cell. This is the transmitted form of the virus, the form that is found in the blood, and the form that rebounds from the latent reservoir. When CD4+/CCR5+ T cells become limiting the virus evolves to use alternative target cells to support viral replication. In the CNS, the virus can evolve to use a cell that displays only a low density of CD4, while maintaining the use of CCR5 as the coreceptor. When this evolutionary variant evolves, it must be sustaining its replication in either macrophages or microglial cells, which display only a low density of CD4 relative to that on T cells. In the blood and lymphoid system, the major switch late in disease is from T cells expressing CD4 and CCR5 to T cells expressing CD4 and CXCR4, with a change in coreceptor specificity. Thus the virus responds in two different ways to different environments when its preferred target cell becomes limiting.
SALMFamide2 and serotonin immunoreactivity in the nervous system of some acoels (Xenacoelomorpha)
Authors: Dittmann Isabel L. , Zauchner Thomas , Nevard Lucy M. , Telford Maximilian J. , Egger Bernhard
Published: February 2018

Acoel worms are simple, often microscopic animals with direct development, a multiciliated epidermis, a statocyst, and a digestive parenchyma instead of a gut epithelium. Morphological characters of acoels have been notoriously difficult to interpret due to their relative scarcity. The nervous system is one of the most accessible and widely used comparative features in acoels, which have a so‐called commissural brain without capsule and several major longitudinal neurite bundles. Here, we use the selective binding properties of a neuropeptide antibody raised in echinoderms (SALMFamide2, or S2), and a commercial antibody against serotonin (5‐HT) to provide additional characters of the acoel nervous system. We have prepared whole‐mount immunofluorescent stainings of three acoel species: Symsagittifera psammophila (Convolutidae), Aphanostoma pisae, and the model acoel Isodiametra pulchra (both Isodiametridae). The commissural brain of all three acoels is delimited anteriorly by the ventral anterior commissure, and posteriorly by the dorsal posterior commissure. The dorsal anterior commissure is situated between the ventral anterior commissure and the dorsal posterior commissure, while the statocyst lies between dorsal anterior and dorsal posterior commissure. S2 and serotonin do not co‐localise, and they follow similar patterns to each other within an animal. In particular, S2, but not 5‐HT, stains a prominent commissure posterior to the main (dorsal) posterior commissure. We have for the first time observed a closed posterior loop of the main neurite bundles in S. psammophila for both the amidergic and the serotonergic nervous system. In I. pulchra, the lateral neurite bundles also form a posterior loop in our serotonergic nervous system stainings.
Values exchange: using online technology to raise awareness of values and ethics in radiography education
Authors: Mc Inerney John , Lees Amanda
Published: February 2018

Introduction

Ethics and values are increasingly significant aspects of patient‐centred healthcare. While it is widely agreed that ethics and values are essential for healthcare delivery, there is also an acknowledgement that these are areas that are challenging to teach. The purpose of this study is to report a small‐scale evaluative research project of a web‐based technology with the educational potential to facilitate learning in relation to ethics, values, self‐reflection and peer‐based learning.

Methods

Five diagnostic radiography students took part in a semi‐structured focus group with the aim of exploring their experiences of using Values Exchange, an online ethical decision‐making framework, to examine practice‐based ethical issues. Transcripts were interrogated for key themes.

Results

From the thematic analysis three major themes emerged, understanding and appreciating others, addressing the theory‐practice gap and delivering a safe and effective learning environment.

Perceived limitations of the platform included students' fear of misinterpreted responses and possibility of poor group dynamics.

Conclusions

There are varied approaches to how ethics and values are taught and assessed within health‐related environments. Values Exchange is one such teaching tool and has been investigated and described positively by radiography students in this study. Online teaching tools can have a positive effect in helping students identify their own values but require skilled implementation to reap positive rewards.
Estimating symbiotic N2 fixation in Robinia pseudoacacia
Authors: Marron Nicolas , Gana Cécilia , Gérant Dominique , Maillard Pascale , Priault Pierrick , Epron Daniel
Published: February 2018

Estimating symbiotic di‐nitrogen (N2) fixation is challenging, especially when working with woody N2 fixers in field trials. Fortunately, isotope methods based on 15N natural abundance or on 15N artificial enrichment (dilution method) make it possible to estimate the proportion of nitrogen derived from the atmosphere (Ndfa) in N2‐fixing species. These methods have been extensively used in the field for herbaceous species, much less for tree species such as alder and acacia, and rarely for black locust (Robinia pseudoacacia). The objectives of this study were to characterize the fixation potential of black locust in a plantation by using the two 15N isotope methods in the field, and to document values of isotope fractionation occurring during N2 fixation (the B value). B values were estimated both by growing trees on an N‐free medium in controlled conditions (Blab) and by making Ndfa calculated with the natural abundance method converge with Ndfa calculated with the 15N dilution method in the field (Bfield). The two methods gave consistent estimates of the B value. B values ranging between –1.4 and –3.2‰ were found, varying with the age of the plant material. Up to 76% of the N in the black locust trees came from the atmosphere, representing more than 45 kg N ha−1 over five years and confirming that black locust may be well adapted to N‐poor soils.
GC‐MS olfactometric and LC‐DAD‐ESI‐MS/MS characterization of key odorants and phenolic compounds in black dry‐salted olives
Authors: Selli Serkan , Kelebek Hasim , Kesen Songul , Sonmezdag Ahmet Salih
Published: February 2018

BACKGROUND

Olives are processed in different ways depending on consumption habits, which vary between countries. Different de‐bittering methods affect the aroma and aroma‐active compounds of table olives. This study focused on analyzing the aroma and aroma‐active compounds of black dry‐salted olives using gas chromatography–mass spectrometry‐olfactometry (GC–MS‐O) techniques.

RESULTS

Thirty‐nine volatile compounds which they have a total concentration of 29 459 µg kg−1, were determined. Aroma extract dilution analysis (AEDA) was used to determine key aroma compounds of table olives. Based on the flavor dilution (FD) factor, the most powerful aroma‐active compounds in the sample were methyl‐2‐methyl butyrate (tropical, sweet; FD: 512) and (Z)‐3‐hexenol (green, flowery; FD: 256). Phenolic compounds in table olives were also analyzed by LC‐DAD‐ESI‐MS/MS. A total of 20 main phenolic compounds were identified and the highest content of phenolic compound was luteolin‐7‐glucoside (306 mg kg−1), followed by verbascoside (271 mg kg−1), oleuropein (231 mg kg−1), and hydroxytyrosol (3,4‐DHPEA) (221 mg kg−1).

CONCLUSION

Alcohols, carboxylic acids, and lactones were qualitatively and quantitatively the dominant volatiles in black dry‐salted olives. Results indicated that esters and alcohols were the major aroma‐active compounds. © 2018 Society of Chemical Industry
Gender Differences in Neurocognitive Performance Among Children With Posttraumatic Stress Disorder and Mild Traumatic Brain Injury
Authors: Segev Shira , Shorer Maayan , Peleg Tammy Pilowsky , Apter Alan , Fennig Silvana , Rassovsky Yuri
Published: February 2018

Posttraumatic stress disorder (PTSD) and mild traumatic brain injury (mTBI) are frequent sequelae after motor vehicle accidents (MVAs). These two pathologies often have overlapping neurocognitive deficits across several domains, such as attention, memory, and executive functions. The present study was an effort to examine the contribution of gender to these overlapping symptoms. To this end, psychodiagnostic and neuropsychological data were collected on 61 children and adolescents 3 months following MVA. All participants were diagnosed with PTSD, and about half (n = 33) also received a diagnosis of mTBI. Analyses of variance revealed significant interactions between gender and mTBI (), such that girls with mTBIs preformed significantly worse than noninjured girls on measures of executive functions (Cohen's d = 3.88) and sustained attention (Cohen's d = 3.24). Boys, on the other hand, did not differ significantly on any of those measures, irrespective of TBI injury status. Similarly, comparisons to the normative population revealed that, whereas boys showed impaired neurocognitive performances regardless of TBI status, impaired performances in girls were limited to those cases in which the girls were comorbid for PTSD and mTBI. It appears then that whereas PTSD alone might explain boys’ reduced neurocognitive performance, among girls the comorbidity of PTSD and mTBI is required to account for performance deficits.
Topiramate as Monotherapy or Adjunctive Treatment for Posttraumatic Stress Disorder: A Meta‐Analysis
Authors: Varma Archana , Moore Michael B. , Miller Christopher W. T. , Himelhoch Seth
Published: February 2018

Posttraumatic stress disorder (PTSD) is a chronic and debilitating condition for which clinicians sometimes turn to anticonvulsants as a treatment for symptoms. This study was a systematic review and meta‐analysis of randomized controlled trials (RCT) that have assessed the efficacy of topiramate as monotherapy or adjunctive therapy, compared to placebo, for the treatment of PTSD in adults. Prescribers may be reluctant to turn to topiramate, given the commonly reported side effects of impaired cognition, sedation, fatigue, and headache. We searched PubMed, PsycInfo, and Cochrane Central databases for relevant trials. Five studies were identified as RCTs and thus met inclusion criteria; one additional nonpublished study was identified via phone contact with its authors. Of these six studies, one was excluded from the statistical meta‐analysis due to its high dropout rate (16 of 40 participants). One of these studies was excluded from a stratified analysis of symptom types because this subscale data were unavailable.  For overall symptomatology, topiramate showed a medium, but not significant effect, standardized mean difference (SMD) = 0.55, p = .082. Topiramate showed a small and significant reduction of hyperarousal symptoms, SMD = 0.35, 95% CI [0.029, 0.689], p = .033. Topiramate did not significantly reduce reexperiencing symptoms, SMD = 0.29, 95% CI [−0.019, 0.597], p = .067, or avoidance symptoms, SMD = 0.20, 95% CI [−0.105, 0.509], p = .198. Results did not differ significantly between veteran and nonveteran subjects, or between topiramate as monotherapy and adjunctive therapy. Further studies on topiramate will clarify its role in PTSD treatment.
Ultrasound Imaging for Traumatic Brain Injury
Authors: Shin Samuel S. , Huisman Thierry A. G. M. , Hwang Misun
Published: February 2018

Traumatic brain injury (TBI) is challenging to assess even with recent advancements in computed tomography and magnetic resonance imaging. Ultrasound (US) imaging has previously been less utilized in TBI compared to conventional imaging because of limited resolution in the intracranial space. However, there have been substantial improvements in contrast‐enhanced US and development of novel techniques such as intravascular US. Also, continued research provides further insight into cerebrovascular parameters from transcranial Doppler imaging. These advancements in US imaging provides the community of TBI imaging researchers and clinicians new opportunities in clinically monitoring and understanding the pathologic mechanisms of TBI.
Telepresent Focused Assessment With Sonography for Trauma Examination Training Versus Traditional Training for Medical Students: A Simulation‐Based Pilot Study
Authors: Poland Scott , Frey Jennifer A. , Khobrani Ahmad , Ondrejka Jason E. , Ruhlin Michael U. , George Richard L. , Gothard M. David , Ahmed Rami A.
Published: February 2018

Objectives

Telepresent education is becoming an important modality in medical education, as it provides a means for instructors to lead education sessions via videoconferencing technologies. This study aimed to compare the effectiveness of telepresent ultrasound training versus traditional in‐person ultrasound training.

Methods

Medical student cohorts were educated by either traditional in‐person instruction or telementoring on how to perform a focused assessment with sonography for trauma (FAST) examination. Effectiveness was evaluated by pre– and post–multiple‐choice tests (knowledge), confidence surveys, and summative simulation scenarios (hands‐on FAST simulation). Formative simulation scenario debriefings were evaluated by each student using the Debriefing Assessment for Simulation in Healthcare student version (DASH‐SV).

Results

Each method of instruction had significant increases in knowledge, confidence, and hands‐on FAST simulation performance (P < .05). The collective increase in knowledge was greater for the in‐person group, whereas the improvement in FAST examination performance during simulations was greater for the telementored group. Confidence gains were comparable between the groups. The DASH‐SV scores were significantly higher for the in‐person group for each criterion; however, both methods were deemed effective via median scoring.

Conclusions

Telepresent education is a viable option for teaching the FAST examination to medical students.
Combining human input with machine learning: A case study
Authors: Upshall Michael
Published: February 2018

Key points

Publishers increasingly wish to create subject collections but need automated systems to carry this out in a cost‐effective fashion.

The capabilities of unsupervised machine‐based tools to create subject collections have improved dramatically.

Experts are still likely to find errors and exceptions in automated unsupervised content extractions and need ways to interact with semantic tools.

Many semi‐automated content solutions require highly skilled and expensive technical staff to develop and maintain them.

Karger's use of UNSILO's Package Manager appears to have improved efficiency and also fed back to UNSILO to help improve the product.
Carbon dioxide and methane emissions of Swedish low‐order streams—a national estimate and lessons learnt from more than a decade of observations
Authors: Wallin Marcus B. , Campeau Audrey , Audet Joachim , Bastviken David , Bishop Kevin , Kokic Jovana , Laudon Hjalmar , Lundin Erik , Löfgren Stefan , Natchimuthu Sivakiruthika , Sobek Sebastian , Teutschbein Claudia , Weyhenmeyer Gesa A. , Grabs Thomas
Published: February 2018

Low‐order streams are suggested to dominate the atmospheric CO2 source of all inland waters. Yet, many large‐scale stream estimates suffer from methods not designed for gas emission determination and rarely include other greenhouse gases such as CH4. Here, we present a compilation of directly measured CO2 and CH4 concentration data from Swedish low‐order streams (> 1600 observations across > 500 streams) covering large climatological and land‐use gradients. These data were combined with an empirically derived gas transfer model and the characteristics of a ca. 400,000 km stream network covering the entire country. The total stream CO2 and CH4 emission corresponded to 2.7 Tg C yr−1 (95% confidence interval: 2.0–3.7) of which the CH4 accounted for 0.7% (0.02 Tg C yr−1). The study highlights the importance of low‐order streams, as well as the critical need to better represent variability in emissions and stream areal extent to constrain future stream C emission estimates.
Supramolecular Stimuli‐Responsive Microgels Crosslinked by Tannic Acid
Authors: López Catalina Molano , Pich Andrij
Published: February 2018

The application of biomolecules as building blocks is substantial for the design of bioinspired dynamic nanomaterials with tailored properties. In this communication, the facile synthesis of aqueous supramolecular temperature‐responsive microgels is reported using the natural polyphenol tannic acid (TA) as physical crosslinker. The precipitation polymerization of N‐vinylcaprolactam in the presence of this polyphenol leads to the formation of well‐defined microgels crosslinked by hydrogen bonds. A systematic variation of the tannic acid content leads to tailored microgel properties. The obtained microgels exhibit reversible temperature‐dependent swelling/deswelling and undergo pH‐triggered degradation in aqueous solutions.
Wave‐CAIPI ViSTa: highly accelerated whole‐brain direct myelin water imaging with zero‐padding reconstruction
Authors: Wu Zhe , Bilgic Berkin , He Hongjian , Tong Qiqi , Sun Yi , Du Yiping , Setsompop Kawin , Zhong Jianhui
Published: February 2018

Purpose

This study introduces a highly accelerated whole‐brain direct visualization of short transverse relaxation time component (ViSTa) imaging using a wave controlled aliasing in parallel imaging (CAIPI) technique, for acquisition within a clinically acceptable scan time, with the preservation of high image quality and sufficient spatial resolution, and reduced residual point spread function artifacts.

Methods

Double inversion RF pulses were applied to preserve the signal from short T1 components for directly extracting myelin water signal in ViSTa imaging. A 2D simultaneous multislice and a 3D acquisition of ViSTa images incorporating wave‐encoding were used for data acquisition. Improvements brought by a zero‐padding method in wave‐CAIPI reconstruction were also investigated.

Results

The zero‐padding method in wave‐CAIPI reconstruction reduced the root‐mean‐square errors between the wave‐encoded and Cartesian gradient echoes for all wave gradient configurations in simulation, and reduced the side‐main lobe intensity ratio from 34.5 to 16% in the thin‐slab in vivo ViSTa images. In a 4 × acceleration simultaneous‐multislice scenario, wave‐CAIPI ViSTa achieved negligible g‐factors (gmean/gmax = 1.03/1.10), while retaining minimal interslice artifacts. An 8 × accelerated acquisition of 3D wave‐CAIPI ViSTa imaging covering the whole brain with 1.1 × 1.1 × 3 mm3 voxel size was achieved within 15 minutes, and only incurred a small g‐factor penalty (gmean/gmax = 1.05/1.16).

Conclusion

Whole‐brain ViSTa images were obtained within 15 minutes with negligible g‐factor penalty by using wave‐CAIPI acquisition and zero‐padding reconstruction. The proposed zero‐padding method was shown to be effective in reducing residual point spread function for wave‐encoded images, particularly for ViSTa.
Lehrer ohne Lehramtsstudium
Authors: Beuttler Holger
Published: February 2018

In naturwissenschaftlichen Fächern fehlt es an Lehrern. Da der Berufseinstieg in die Industrie für Chemiker zurzeit nicht ganz einfach ist, erscheint der Wechsel ins Lehramt als Alternative. Allerdings unterscheiden sich Chancen und Einstellungsvoraussetzungen für Quereinsteiger von Bundesland zu Bundesland.
Von Hochkultur zum Niedergang: Briefe in der Chemie
Authors: Zott Regine
Published: February 2018

Als „eine Unterred oder Wechselung zwischen Abwesenden, in der Schrift bestehend“1) wird der Brief im Jahr 1673 definiert. In der Chemie dienten Briefe seit dem 19. Jahrhundert dem Abstecken von Fachgebieten, der Organisation der ersten internationalen Fachtagung, der Kritik und der Unterstützung von Freunden und Kollegen.
Strukturchemie ‐ Ein Hauch von Nichts
Authors: Steinhauser Georg
Published: February 2018

Bereits Spuren des Actinoids Americium bestimmen die Kristallstruktur eines Terbiumsalzes.
Mehr als nicht unschuldig ‐ NO in der Bioanorganik
Authors: Aas Bianca M. , Beck Daniel , Daumann Lena J.
Published: February 2018

Lang als Luftverschmutzer und giftiges, unerwünschtes Gas abgestempelt, erfreuen sich seit seiner Entdeckung als physiologisch wichtiges Molekül Forscher an Stickstoffmonoxid. Die biologisch relevanten Wechselwirkungen mit Eisenzentren haben in der Koordinationschemie zu einer Renaissance für diesen nicht unschuldigen Liganden geführt.
Hochschuldidaktik: Elektrogeneriertes Leuchtsignal zeigt Spurenstoffe an
Authors: Habekost Achim
Published: February 2018

Die elektrogenerierte Chemilumineszenz (ECL) ist nicht nur durch seine Leuchterscheinung für Lernende attraktiv. Das Phänomen ist auch für chemische Analytik nutzbar. Versuche mit der ECL von Trisbipyridylruthenium (II) aus dem Hochschulpraktikum.
Ist mein Lebensmittel noch frisch?
Authors: van Alst Lea
Published: February 2018

Im Schnitt landen in Deutschland jährlich 6,7 Millionen Tonnen Lebensmittel im Müll. Ihr Makel ist das abgelaufene Mindesthaltbarkeitsdatum, bei dem Lebensmittel oft noch genießbar sind. Daher entwickeln Forscher Schnellanalysenmethoden, um ihren Zustand zu überprüfen.
Chemikalienregulierung ‐ Chip statt Maus
Authors: Ehrensberger Christian
Published: February 2018

Bei der Einführung der EU‐Chemikalienverordnung Reach kamen schnell Warnungen auf, es könnten zusätzliche und umfangreichere Tierversuche nötig werden. Inzwischen gibt es Verfahren, ohne Tierversuche die Risiken von Chemikalien abzuschätzen.
Prozessindustrie: Keine Diskussionen mehr
Authors: Hundertmark Stephan
Published: February 2018

Der Prozessindustrie stehen genügend Steuerungsgrößen zur Verfügung. Unternehmen müssen diese verknüpfen und Schlüsse daraus ziehen.
Aktiv auch noch im Ruhestand
Authors: Jäckel Klaus‐Peter
Published: February 2018

Seit dem Jahr 2007 verhelfen die Seniorexperten Chemie den älteren GDCh‐Mitgliedern zu mehr Sichtbarkeit in der GDCh.
Computing the nearest stable matrix pairs
Authors: Gillis Nicolas , Mehrmann Volker , Sharma Punit
Published: February 2018

In this paper, we study the nearest stable matrix pair problem: given a square matrix pair (E,A), minimize the Frobenius norm of (ΔE,ΔA) such that (E+ΔE,A+ΔA) is a stable matrix pair. We propose a reformulation of the problem with a simpler feasible set by introducing dissipative Hamiltonian matrix pairs: A matrix pair (E,A) is dissipative Hamiltonian if A=(J−R)Q with skew‐symmetric J, positive semidefinite R, and an invertible Q such that QTE is positive semidefinite. This reformulation has a convex feasible domain onto which it is easy to project. This allows us to employ a fast gradient method to obtain a nearby stable approximation of a given matrix pair.
An investigation on the reinforcement mechanism of the nano‐sized carbonaceous filled epoxy‐glass fiber hybrid‐composites through analysis of fracture surfaces
Authors: Soltani Ehsan , Shahrousvand Mohsen , Babaei Amir
Published: February 2018

The objective of this work was to investigate the influence of delamination degree of the graphite on the mechanical properties of glass fiber/epoxy composite. To aim this, graphene and highly expanded graphite (HEG) nanofillers were synthesized using intensive ultrasonic method and were added to the epoxy and also glass fiber/epoxy composite, separately. Subsequently, tensile, flexural and impact strength of prepared samples were studied. Furthermore, the lateral size and dispersion quality of synthesized fillers in the epoxy matrix was inspected through using field emission scanning electron microscopy. Mechanical results demonstrated an enhancement by addition of both synthesized nanofillers to both nanocomposites and hybrid‐composites. Highest increment rate of tensile strength was related to the nanocomposites containing 0.5 wt% nanofillers in which 61 and 51% enhancement for graphene nanoplate and highly expanded graphite loaded samples, respectively, was observed compared with the neat epoxy. It was found that, degree of delamination and dispersion of graphite platelets has a fundamental influence on the mechanical properties. In addition, fracture surface of epoxy nanocomposites and hybrid‐composites were inspected to study the toughening mechanism. POLYM. COMPOS., 39:E2460–E2471, 2018. © 2018 Society of Plastics Engineers
Confidence and Prediction Intervals for Pharmacometric Models
Authors: Kümmel Anne , Bonate Peter L. , Dingemanse Jasper , Krause Andreas
Published: February 2018

Supporting decision making in drug development is a key purpose of pharmacometric models. Pharmacokinetic models predict exposures under alternative posologies or in different populations. Pharmacodynamic models predict drug effects based on exposure to drug, disease, or other patient characteristics. Estimation uncertainty is commonly reported for model parameters; however, prediction uncertainty is the key quantity for clinical decision making. This tutorial reviews confidence and prediction intervals with associated calculation methods, encouraging pharmacometricians to report these routinely.
Intermetallic Pd3Pb Nanoplates Enhance Oxygen Reduction Catalysis with Excellent Methanol Tolerance
Authors: Wang Kai , Qin Yingnan , Lv Fan , Li Mingqiang , Liu Qiao , Lin Fei , Feng Jianrui , Yang Chao , Gao Peng , Guo Shaojun
Published: February 2018

Herein, a new class of intermetallic Pd3Pb square nanoplates (SNP) and nanoplates assemblies is demonstrated with tunable crystalline orientation for boosting oxygen reduction reaction (ORR) activity and stability with excellent methanol tolerance. The Pd3Pb intermetallic nanostructures show the crystalline‐orientation‐dependent electrocatalytic activity for ORR with (100)‐facet‐dominated Pd3Pb SNP being the most active. The Pd3Pb intermetallic SNP exhibits the highest ORR mass activity of 0.78 A mg−1 at 0.9 V versus reversible hydrogen electrode in alkaline electrolyte for the state‐of‐art reported Pd‐based nanocatalysts, 7.1 times higher than that of commercial Pt/C. The unique structure of Pd3Pb intermetallic SNP makes it highly stable for ORR with almost no activity decrease and no composition and morphology changes after a 5000‐cycle durability test. The Pd3Pb intermetallic SNP also exhibits much higher methanol tolerance behavior than commercial Pt/C and Pd/C during ORR catalysis. Density functional theory calculations reveal that presence of Pb decreases adsorption strength of methanol on Pd3Pb intermetallic SNP. The calculated Emethanol follows the order of Pd3Pb (100) < Pd (111) < Pt (111) with (100)‐oriented Pd3Pb SNP having the lowest methanol adsorption energy, thus boosting methanol tolerance performance.
Recovering disk storage metrics from low‐level trace events
Authors: Daoud Houssem , Dagenais Michel R.
Published: February 2018

Block devices such as magnetic disks are nonvolatile data storage devices that transfer data in fixed‐size chunks. They are the main nonvolatile memory that holds the file system, and they are also used in virtual memory mechanisms such swapping and page fault handling. Investigating storage performance issues requires a full insight into the operating system internals. Kernel tracing offers an efficient mechanism to gather information about the storage subsystem at runtime. Still, the tracing output is often huge and difficult to analyze manually.

In this paper, we introduce a framework to compute meaningful storage performance metrics from low‐level trace events generated by LTTng. A stateful approach is used to model the state of the storage subsystem. Efficient data structures and algorithms are proposed to offer a reasonable response time, allowing the user to navigate throughout the trace and to retrieve metrics from any time range. The framework includes a visualization system that provides different graphical views that represent the collected information in a convenient way. These views are synchronized together, forming a comprehensive perspective that makes storage performance investigation a much more comfortable task. Different use cases are presented to show the usefulness of the framework in real‐world applications.
Nanoporous silica aerogel modified by triethylchlorosilane as a new sorbent for the needle‐trap extraction
Authors: Roostaie Ali , Bargozin Hasan , Mohammadiazar Sirwan , Ehteshami Shokooh
Published: February 2018

In this work, nanoporous silica aerogel modified by triethylchlorosilane is used as a new sorbent for headspace needle‐trap extraction of chlorobenzenes from aqueous samples. The needle trap extraction is derived from solid‐phase microextraction, and the sorbent is in the inside a needle. The thermal stability and functional groups of the sorbent were studied by thermal gravimetric/differential thermal analyses and FTIR spectroscopy, respectively. The modified silica aerogel characterized by field‐emission scanning electron microscopy shows a 3D network containing homogeneous pore structure with pore sizes of a few tens of nm and a nanoporous structure. The influential parameters on the extraction efficiency, including the extraction temperature, ionic strength and extraction time, were optimized. Under optimized conditions, the detection limit and quantification limit were obtained in the range of 0.3–1 and 1–3 ng/L, respectively. The relative standard deviation values for water spiked with the chlorobenzenes at 100 ng/L under optimum conditions were 3–9%. The dynamic linear range of method was investigated in the range of 3–3000 ng/L. Finally, the current method for the analysis of real water samples containing spiked chlorobenzenes was applied and the relative recovery values were found to be in the range of 96–101%.
Recent Advances in Ring‐Opening Functionalization of Cycloalkanols by C–C σ‐Bond Cleavage
Authors: Wu Xinxin , Zhu Chen
Published: February 2018

Cycloalkanols prove to be privileged precursors for the synthesis of distally substituted alkyl ketones and polycyclic aromatic hydrocarbons (PAHs) by virtue of cleavage of their cyclic C−C bonds. Direct functionalization of cyclobutanols to build up other chemical bonds (e. g., C−F, C−Cl, C−Br, C−N, C−S, C−Se, C−C, etc.) has been achieved by using the ring‐opening strategy. Mechanistically, the C−C cleavage of cyclobutanols can be involved in two pathways: (a) transition‐metal catalyzed β‐carbon elimination; (b) radical‐mediated ‘radical clock’‐type ring opening. The recent advances of our group for the ring‐opening functionalization of tertiary cycloalkanols are described in this account.
Neonatal Gastric Perforation: Case Series and Literature Review
Authors: Yang Tianyou , Huang Yongbo , Li Jiahao , Zhong Wei , Tan Tianbao , Yu Jiakang , Li Le , Pan Jing , Hu Chao , Yang Jiliang , Zou Yan
Published: February 2018

Purpose

We reported clinical findings of neonatal gastric perforation in a tertiary children’s hospital.

Patients and methods

Retrospective chart reviews were conducted for neonatal gastric perforation between 1980 and 2016. Factors including sex, gestational age, birth weight, age, main symptoms and signs, white blood cell count (WBC), surgical intervention time (time between development of main symptom and surgical intervention), surgical findings, pathologic results, clinical outcomes, and causes of death were collected.

Results

Sixty‐eight patients were identified. In total, 76.5% were male infants, the median age was 4 days, median birth weight was 2500 g, and 42.6% were premature. Abdominal distention and vomiting were the most common symptoms, and pneumoperitoneum was the most common radiographic finding. The median surgical intervention time was 51 h (range 8–312). In total, 73.5% of perforations occurred in the great curvature, 17.6% in the lesser curvature, and 8.9% unspecified. The median perforation size was 4 cm (range 0.2–16). Associated gastrointestinal anomalies were found in 20.6% of patients, and the most common anomaly was intestinal malrotation. Of the 51 patients with pathologic results, 11 showed the presence of musculature in the perforated gastric wall, while 40 showed the absence of musculature. Of the 66 patients with known clinical outcomes, 26 (39.4%) died, 23 of who died of infection. Among those aforementioned factors, WBC has a significant impact on survival. The mortality for four arbitrary divided year groups (1980–1989, 1990–1999, 2000–2009, and 2010–2016) was 100, 50, 31.6, and 16.7%, respectively.

Conclusions

The mortality of neonatal gastric perforation is constantly decreasing. Associated gastrointestinal anomalies and the presence of musculature are found in a minority of this condition.
Classic Primary Hyperparathyroidism Versus Normocalcemic and Normohormonal Variants: Do They Really Differ?
Authors: Kiriakopoulos Andreas , Petralias Athanasios , Linos Dimitrios
Published: February 2018

Background

Normocalcemic (NCpHPT) and normohormonal (NHpHPT) variants have been recognized primary hyperparathyroidism entities that pose serious challenges. We sought to define the differences among them in a series of surgically treated patients.

Patients and methods

Between 2011 and 2015, 149 patients were enrolled into three groups: CpHPT (Ca > 10.2 mg/dL, PTH > 65 pg/mL), NCpHPT (normal Ca, PTH > 65 pg/mL) and NHpHPT (Ca > 10.2 mg/dL, normal PTH). Descriptive statistics and inter‐group differences were computed, whereas multiple logistic/linear regression tests were used for further analysis.

Results

Of these patients 125 were female and 24 male, mean age 56.3 years (range 8–83). A total of 115 (77.2%) patients presented with CpHPT, 23 (15.4%) with NCpHPT and 11 (7.4%) with NHpHPT. MGD was found in 25 (16.8%) patients and SGD in 124 (83.2%); multivariate analysis failed to reveal statistically significant association of MGD with any pHPT variant (CpHPT 16.5% vs NCpHPT 21.7% vs NHpHPT 9.1%, p = 0.726). Conversely, NCpHPT patients exhibited statistically significant smaller adenoma weight (p = 0.023). Moreover, U/S in these patients had smaller positive predictive value (p = 0.278), whereas concordance between U/S and MIBI was also lower (p = 0.669). The utility of MIBI and U/S differed significantly (p < 0.001); more frequent use of U/S was observed for all groups. However, their predictive values did not differ significantly (p = 0.832).

Conclusions

NCpHPT is more similar than different to CpHPT. NCpHPT constitutes the most challenging entity: it is associated with smaller adenoma weight, whereas U/S exhibited lower positive predictive value and lower concordance rate with MIBI. A trend for higher MGD presence in this group of patients was observed, though without statistical significance.
Low-Intensity Shockwave Therapy for Erectile Dysfunction: A Randomized Clinical Trial Comparing 2 Treatment Protocols and the Impact of Repeating Treatment
Authors: Kalyvianakis Dimitrios , Memmos Evangelos , Mykoniatis Ioannis , Kapoteli Paraskevi , Memmos Dimitrios , Hatzichristou Dimitrios
Published: February 2018

Background

There is lack of evidence-based optimization of the protocol for low-intensity shockwave therapy for erectile dysfunction. Furthermore, the safety and efficacy of repeating shockwave therapy have not been explored.

Aim

To compare the efficacy and safety of 6 and 12 treatment sessions within a 6-week treatment period and investigate the effect of repeat treatment after a 6-month period in a 2-phase study.

Methods

Patients with vasculogenic erectile dysfunction that responded to phosphodiesterase type 5 inhibitors were randomized into 2 groups: low-intensity shockwave therapy sessions once (group A, n = 21) or twice (group B, n = 21) per week for 6 consecutive weeks (phase 1). Patients who completed 6-month follow-up were offered 6 additional sessions (phase 2); group A received 2 sessions per week and group B received 1 session per week. Patients were followed for 6 months.

Outcomes

International Index for Erectile Function erectile function domain (IIEF-EF) score, minimally clinical important differences (MCIDs), Sexual Encounter Profile question 3 (SEP3) score, and triplex ultrasonographic parameters.

Results

In phase 1, groups A and B showed improvement in IIEF-EF score, MCID, SEP3 score, and mean peak systolic velocity compared with baseline. MCIDs were achieved in 62% of group A and 71% of group B, and the percentage of yes responses to SEP3 was 47% in group A and 65% in group B (P = .02). Mean peak systolic velocity at baseline and at 3-month follow-up were 29.5 and 33.4 cm/s for group A and 29.6 and 35.4 cm/s for group B (P = .06). In phase 2, group A showed a greater increase in the percentage of yes responses to SEP3 (group A = +14.9; group B = +0.3). When the impact of the total number of sessions received was examined, MCIDs in IIEF-EF score from baseline were achieved in 62%, 74%, and 83% of patients after 6, 12, and 18 sessions, respectively. No treatment-related side effects were reported.

Clinical Implications

The total number of low-intensity shockwave therapy sessions affects the efficacy of erectile dysfunction treatment. Retreating patients after 6 months could further improve erectile function without side effects. 12 sessions can be delivered within 6 weeks without a 3-week break period.

Strengths and Limitations

This study lacked a sham-controlled arm. However, all patients were randomized to different groups, and baseline characteristics were similar between groups. Also, all patients were confirmed by triplex ultrasonography to have arterial insufficiency.

Conclusion

Patients can benefit more in sexual performance from 12 sessions twice per week compared with 6 sessions once a week. Shockwave therapy can be repeated up to a total of 18 sessions.
Centrality of religiosity versus civic involvement. The case of Poland
Authors: Turska-Kawa Agnieszka
Published: February 2018

The article is an expression of search for the motivational role of religiosity in individuals’ civic activity. Mature civic attitude is shaped by the person’s values, individual and communal needs, and experience. The main thesis of the presented study is that the relation between religiosity and human will in many points overlap with the factors which determine the citizen’s activity for the benefit of the community. Stefan Huber’s Centrality of Religiosity Scale emphasizing the primary importance of the motivational value of religiosity and an original scale measuring civic involvement were used in the study (N = 732). The study proved that religiosity mostly serves as a civic involvement predictor among women from the middle age group. Although a higher level of civic involvement was found in men, religiosity did not prove to be a significant factor explaining its higher level, which means that the determinants for it need to be sought in other spheres.
Wilderness First Responder: Are Skills Soon Forgotten?
Authors: Rhue Alexandra L. , VanDerveer Beth
Published: February 2018

Wilderness first responders are trained to provide competent medical care in wilderness settings or until evacuation for more advanced treatment can be obtained. In light of the isolated environments in which they are called upon to respond to illnesses and injuries, their ability to effectively apply their training is crucial. Despite the responsibility assigned to them, there is an absence of research assessing the skill and knowledge retention of wilderness first responders, creating a gap in understanding whether a deficit in their ability to perform exists between certifications. Without such research, it is important to review knowledge and skill retention in related responder groups. The literature over the past 4 decades documents the loss over time of skills and knowledge across an array of trained responders, both professional and laypeople. Although the findings reviewed suggest that WFRs will exhibit a similar pattern of increasing skill loss beginning shortly after certification and a slower, but concurrent, decrease in knowledge, research is needed to document or refute this assumption.
Proteomics pattern associated with gingival oral squamous cell carcinoma and epulis: A case analysis
Authors: Papa Francesco , Siciliano Rosa Anna , Inchingolo Francesco , Mazzeo Maria Fiorella , Scacco Salvatore , Lippolis Rosa
Published: February 2018

Objectives: Oral squamous cell carcinoma (OSCC) is the most common epithelial malignant neoplasm affecting the oral cavity. OSCC can mimic oral lesions of inflammatory origin with benign features, often leading to delay in diagnosis and treatment. Early detection is important to greatly increase the chances of a successful treatment. The present study reports a proteomic analysis of a gingival oral squamous cell carcinoma (G‐OSCC) and an epulis.

Materials and methods: Normal mucosae tissue, G‐OSCC tissue, and epulis tissue as a comparative sample of benign nature were collected and immediately frozen in liquid nitrogen. Tissue‐extracted proteins were separated by two‐dimensional gel electrophoresis and subjected to image analysis. Proteins that showed a significant difference in the expression level in the G‐OSCC tissue were identified by the nano‐ESI‐HPLC‐MS/MS experiment and database searchi.

Results and conclusion: The proteomic analysis of G‐OSCC tissue enabled the identification of proteins that are potentially related to the disease; these proteins can be considered as signature molecules for diagnostic and prognostic tumor markers.
Design and content validation of a set of SMS to promote seeking of specialized mental health care within the Allillanchu Project
Authors: Toyama M. , Diez-Canseco F. , Busse P. , Del Mastro I. , Miranda J. J.
Published: February 2018

Background

The aim of this study was to design and develop a set of, short message service (SMS) to promote specialized mental health care seeking within the framework of the Allillanchu Project.

Methods

The design phase consisted of 39 interviews with potential recipients of the SMS, about use of cellphones, and perceptions and motivations towards seeking mental health care. After the data collection, the research team developed a set of seven SMS for validation. The content validation phase consisted of 24 interviews. The participants answered questions regarding their understanding of the SMS contents and rated its appeal.

Results

The seven SMS subjected to content validation were tailored to the recipient using their name. The reminder message included the working hours of the psychology service at the patient's health center. The motivational messages addressed perceived barriers and benefits when seeking mental health services. The average appeal score of the seven SMS was 9.0 (SD±0.4) of 10 points. Participants did not make significant suggestions to change the wording of the messages.

Conclusions

Five SMS were chosen to be used. This approach is likely to be applicable to other similar low-resource settings, and the methodology used can be adapted to develop SMS for other chronic conditions.
Exploring with Māori organizations comparative advantage in the context of climate change
Authors: Beall Elizabeth , Brocklesby John
Published: February 2018

This paper reports on a project conducted with representatives of indigenous Māori organizations that are active in New Zealand land-based sectors. The primary aim of the research was to assist these organizations in thinking about their current and future positioning with regard to climate change. Using Peter Checkland’s Soft Systems Methodology as a broad framework for the research, the paper first seeks to capture some of the likely issues that enable and constrain strategic activity in the climate change arena. It then uses various soft systems modelling tools to research and structure a debate to consider the desirability and feasibility of particular interventions.
How does enterprise assistance support Māori entrepreneurs? An identity approach
Authors: Warren Lorraine , Mika Jason , Palmer Farah
Published: February 2018

Indigenous entrepreneurs represent a growing segment of the business community in many countries, but face sometimes stark challenges in starting and running enterprises. The success of indigenous entrepreneurs matters because they draw upon their indigeneity as sources of inspiration and innovation, contribute to the collective wellbeing of indigenous peoples, and some represent world class exemplars of sustainable ways of doing business. While enterprise assistance for entrepreneurs is widely accepted as a worthwhile use of public funds few guidelines exist to help policy makers and providers understand the needs of indigenous entrepreneurs and how best to respond. In this paper, we use the theoretical lens of entrepreneurial identity to provide insight into this challenging context. Taking an identity perspective may enable us to tease out how identifying as a Māori entrepreneur can enable and also hinder change in this community context. In doing so we lay foundations for future empirical work.
The curvilinear relationship between team familiarity and team innovation: A secondary data analysis
Authors: Xie Xiao-Yun , Ji Hao , Luan Kun , Zhao Ying-Zhen
Published: February 2018

Paradoxical arguments and mixed empirical evidence coexist in the current literature concerning the relationship between team familiarity and team innovation. To resolve this contradiction, we apply habitual routines theory to propose that team familiarity and team innovation have an inverted U-shaped relationship. Using a data set of 68,933 R&D teams in the electrical engineering industry, our results support a nonlinear relationship between team familiarity and team innovation, and suggest that the best innovative performance is produced by moderately familiar teams. Furthermore, we find that external learning can moderate this curvilinear relationship. Theoretical contributions and future implications are discussed.