bluuebunny/crossref_metadata_2025 huggingface dataset:
Molybdenum Imido, Tungsten Imido and Tungsten Oxo Alkylidene N‐Heterocyclic Carbene Olefin Metathesis Catalysts
Authors: Buchmeiser Michael R.
Published: June 2018

This article outlines the fundamental concept to molybdenum imido, tungsten imido and tungsten oxo alkylidene N‐heterocyclic carbene (NHC) catalysts for olefin metathesis. Starting from Mo(NR)(CHCMe2R′)(OTf)2⋅DME (R=alkyl, aryl; R′=CH3, Ph; OTf=CF3SO3; DME=1,2‐dimethoxyethane), W(NR)(CHCMe2Ph)X2 (X=pyrrolide, OR′′, SiPh3) and W(O)Cl2(CHCMe2Ph)(PMe2Ph)2, respectively, the neutral, pentacoordinated 16‐valence electron (VE) complexes became accessible. These serve as precursors for the corresponding cationic, tetracoordinated 14‐VE catalysts. This class of olefin metathesis catalysts based on group 6 metal alkylidene NHCs is characterized by a broad structural variability, high activity, high productivity and, in tailored systems, high functional group tolerance even vs. protic groups including alcohols and carboxylic acids. Also, high regio‐ and stereoselectivity is achieved, both in ring‐opening metathesis polymerization (ROMP) and in the cyclopolymerization of α,ω‐diynes. Fundamentals concerning the influence of the imido/oxo ligand, the different NHCs and the anionic ligands on catalyst performance and stability as well as reaction pathways are summarized. Also, the concepts for catalyst immobilization, whether via the NHC or by substitution of an alkoxide, are presented. Finally, special features such as the use of betaine‐type anionic ligands (alkoxides and sulfonates), which offer access to ionic catalysts for use biphasic reaction setups, are briefly outlined.
Structural Designs for Accommodating Volume Expansion in Sodium Ion Batteries
Authors: Wang Wenjie , Zhu Xiaohui , Zhang Yujing , Liu Yongjun , Zhang Qin , Fu Lei
Published: June 2018

At the forefront of energy storage field, developing sodium ion batteries (SIBs) has drew a wide concern due to relatively low cost and abundant resource, comparing with lithium ion batteries (LIBs). Serious volume expansion constraints the electrochemical performance of the conversion/alloying materials, despite of their high reversible capacities or theoretical capacities. Here, from the perspective of structural designs, we systematically study four types of routes to accommodate volume expansion. Delicate and peculiar nanostructures based on nanocrystallization engineering are widely focused on, covering nanosheet assembly and nanoarray construction. Robust materials such as carbon‐based materials can be utilized as the buffer matrix, mitigating the mechanical stress during the charge/discharge process. Besides, recent studies have demonstrated void space reservation in nanostructures was also beneficial for adapting to volume changes. Moreover, for conversion materials, numerous works have confirmed the advantageous influence of interlayer spacing regulation. We also explained the superiority and challenges for further giving scope to structural designs. Sketching out the future studies in SIBs, in situ characterizations are supposed to be highlighted, as well as in‐depth researches on the stress evolution caused by volume expansion.
Aspirin® – so schnell wie nie?!
Authors: Rodriguez Maren , Salzner Jens , Lühken Arnim
Published: June 2018

Der Beitrag stellt eine alltags‐ und problemorientierte Lerngelegenheit vor. Das Werbeversprechen „Aspirin® – so schnell wie nie, dank MicroAktiv‐Technologie“ wird durch Einsatz eines schultauglichen Modells einer pharmazeutischen „Basket‐Apparatur“ und der Photometrie mit Hilfe des Smartphones schulexperimentell überprüft und sachgerecht bewertet.
Assessing and fostering students’ scientific literacy in doing comparative investigation tasks
Authors: Hild Pitt , Metzger Susanne , Parchmann Ilka
Published: June 2018

Dieser Artikel liefert konkrete Beispiele zur Beurteilung und Förderung experimenteller Kompetenzen im Bereich Erkenntnisgewinnung. Es werden zunächst Grundlagen für die Entwicklung kompetenzorientierter hands‐on Experimentieraufgaben am Beispiel des „effektbasierten Vergleichens“ beschrieben. Bei diesen Aufgaben müssen Schülerinnen und Schüler unterschiedliche Objekte anhand einer gegebenen Eigenschaft experimentell vergleichen. Unterschiedliche zu erreichende Kompetenzen aus dem Bereich der Erkenntnisgewinnung wurden a priori, anhand eines Strukturmodells, postuliert. Mithilfe validierter Testaufgaben und eines standardisierten Manuals konnte bei einer Stichprobe von 418 12‐ bis 15‐jährigen Schülerinnen und Schülern (jeweils 2 Aufgaben mit gleichem Aufgabenstamm pro Person) eine Progression entlang dieser Kompetenzen nachgewiesen werden. Die Übereinstimmungen zwischen den Prüferinnen und Prüfern liegen alle in einem akzeptablen bis sehr guten Bereich. Die Ergebnisse sollen die Grundlage für die Konstruktion von Lernumgebungen liefern, die es den Lehrpersonen erlauben, Kompetenzen im Bereich der Erkenntnisgewinnung zu beurteilen und individuell zu fördern.
Use of the progression of adapted Diabetes Complications Severity Index to predict acute coronary syndrome, ischemic stroke, and mortality in Asian patients with type 2 diabetes mellitus: A nationwide cohort investigation
Authors: Hu Wei‐Syun , Lin Cheng‐Li
Published: June 2018

Background

We report on a retrospective population study aimed at identifying and validating the progression of adapted Diabetes Complications Severity Index (DCSI) for acute coronary syndrome (ACS), ischemic stroke, and mortality in Asian people with type 2 diabetes mellitus (DM).

Methods

Utilizing a Taiwanese national dataset, we included 84 450 type 2 diabetic individuals between 2000 and 2011. The area under the receiver operating characteristic curve (C statistics of logistic model) and the C statistics of the Cox model were used to evaluate whether the progression of diabetic complication status could be a predictor of ACS, ischemic stroke, and death. The optimum threshold for adverse outcomes risk stratification were obtained using Youden's J statistic as the cutoff that gives the highest threshold.

Results

Among the study patients, the C statistics of the logistic model of the progression of the score predictive of ACS, ischemic stroke, and death were 0.72 (95% confidence interval [CI]: 0.71–0.73), 0.84 (95% CI: 0.84–0.85), and 0.66 (95% CI: 0.65–0.67), respectively. The progression of adapted DCSI had moderate discrimination for ACS, ischemic stroke, and death (C statistics = 0.71, 0.72, and 0.75, respectively) based on Cox regression analysis (Harrell C). The optimum threshold of the progression of the score for ACS, ischemic stroke, and death in type 2 DM patients were 0.30, 0.36, and 0.39, respectively.

Conclusions

The acceptable discriminative power of the progression of adapted DCSI for Asian people affected by type 2 DM was demonstrated in a large cohort in Taiwan.
Advanced chronic kidney disease: Relationship to outcomes post‐TAVR, a meta‐analysis
Authors: Makki Nader , Lilly Scott M.
Published: June 2018

Chronic kidney disease (CKD) is associated with worse outcomes in high‐surgical‐risk patients undergoing transcatheter aortic valve replacement (TAVR). However, it is unclear whether this relationship is apparent in lower‐surgical‐risk patients. We sought to analyze existing literature to assess whether or not advanced CKD is associated with increased mortality or a greater incidence of adverse events (specifically major stroke, bleeding, and vascular complications). We searched PubMed and Embase (2008–2017) for relevant studies. Studies with <1 year follow‐up and those not evaluating advanced CKD or outcomes post‐TAVR were excluded. Our co–primary endpoints were the incidence of short‐term mortality (defined as in‐hospital or 30‐day mortality) and long‐term mortality (1 year). Our secondary endpoints included incidence of major stroke, life‐threatening bleeding, and major vascular complications. Eleven observational studies with a total population of 10709 patients met the selection criteria. Among patients with CKD there was an increased risk of short‐ and long‐term mortality in high‐surgical‐risk patients who underwent TAVR (hazard ratio [HR]: 1.51, 95% confidence interval [CI]: 1.22–1.88 and HR: 1.56, 95% CI: 1.38–1.77, respectively; P < 0.01). However, there was no association between CKD and mortality in low‐ to intermediate‐risk patients (HR: 1.35, 95% CI: 0.98–1.84, P = 0.06 in short‐term and HR: 1.08, 95% CI: 0.92–1.27, P = 0.34 in long‐term). In low‐ to intermediate‐risk TAVR patients, advanced CKD is not associated with increased mortality or poorer safety outcomes. These findings should be factored into the clinical decision‐making process regarding TAVR candidacy.
Galectin‐3 and ST2 as predictors of therapeutic success in high‐risk patients undergoing percutaneous mitral valve repair (MitraClip)
Authors: Dörr Oliver , Walther Claudia , Liebetrau Christoph , Keller Till , Sommer Thomas , Boeder Niklas , Bayer Matthias , Bauer Pascal , Möllmann Helge , Gaede Luise , Troidl Christian , Voss Sandra , Bauer Timm , Hamm Christian W. , Nef Holger
Published: June 2018

Background

Percutaneous mitral valve repair (PMVR) is an interventional treatment option in patients with severe mitral regurgitation (MR) and at high risk for open‐heart surgery. Currently, limited information exists about predictors of procedural success after PMVR. Galectin‐3 (Gal‐3) and suppression of tumorigenicity 2 (ST2) induce fibrotic alterations in severe MR and heart failure. We sought to examine the predictive value of Gal‐3 and ST2 as specific indicators of therapeutic success in high‐risk patients undergoing PMVR.

Hypothesis

We hypothesize that extended cardiac fibrotic alterations might have impact on successful MR reduction after the MitraClip procedure.

Methods

A total of 210 consecutive patients undergoing PMVR using the MitraClip system were included in this study. Procedural success was defined as an immediate reduction of MR by ≥2 grades, assessed by echocardiography. Venous blood samples were collected prior to PMVR and at 6 months follow‐up for biomarker analysis.

Results

After PMVR there was a significant reduction in the severity of MR (MR grade: 3 ±0.3 vs 1.6 ±0.6, P <0.001). Low baseline Gal‐3 levels (PMVRsuccess: 22.0 ng/mL [IQR, 17.3‐30.9] vs PMVRfailure: 30.6 ng/mL [IQR, 24.8‐42.3], P <0.001) and ST2 levels (PMVRsuccess: 900.0 pg/mL [IQR, 619.5‐1114.5] vs PMVRfailure: 1728.0 pg/mL [IQR, 1051.March 1, 1930], P < 0.001) were associated with successful MR reduction after PMVR. Also, ROC analysis identified low baseline Gal‐3 and ST2 levels as predictors of therapeutic success after PMVR (AUCGal‐3:0.721 [IQR, 0.64‐0.803], P < 0.001; AUCST2: 0.807 [IQR, 0.741‐0.872], P < 0.001).

Conclusions

There was an association between low Gal‐3 and ST2 plasma levels and successful MR reduction in patients with severe MR undergoing PMVR using the MitraClip system.
NiAl Layered Double Hydroxides and PdNiO as Multifunctional Anodes for Prospective Self‐Powered Lab‐on‐a‐Chip Dopamine Sensors
Authors: Galindo‐de‐la‐Rosa J. , Arriaga L. G. , Álvarez A. , Arjona N. , Déctor A. , Chavéz‐Ramírez A. U. , Vallejo‐Becerra V. , Ledesma‐García J.
Published: June 2018

The purpose of this work is the evaluation of two bimetallic materials, PdNiO and NiAl‐layered double hydroxides (NiAl‐LDHs) for their prospective use in Lab‐on‐a‐Chip devices, in which urea contained in human urine is used as fuel to provide the energy required by the device and dopamine in the sample is detected. A urea microfluidic fuel cell, using human urine as fuel and NiAl‐LDHs and PdNiO as anodes, was constructed and evaluated, resulting in a cell potential of 1 V with 50.19 mW/cm2 power density for NiAl‐LDHs and 0.9 V and 32.94 mW/cm2 for PdNiO. The multifunctionality of these anodes was extended for detecting dopamine with detection limits of 7.38×10−8 M and 5.46×10−6 M for NiAl‐LDHs and PdNiO, respectively. The higher content of hydroxides on NiAl‐LDHs than PdNiO material allowed a better activity for urea oxidation and dopamine detection. These results show the prospects for self‐powered biomedical Lab‐on‐a‐Chip device development.
Boron Centres Allow Design, Control and Systematic Tuning of Neutral Homoaromatics for Functionalization Purposes
Authors: Mattock James D. , Vargas Alfredo
Published: June 2018

Homoaromatic compounds are currently viewed mainly as an interesting novelty with little to no practical application. Based on calculations within density functional theory, we show that the unique charge redirection properties of tricoordinate boron, along with it being isolobal to a carbocation, allow for a larger range of two‐electron donors to be utilized, leading to the rational design of homoaromatic compounds better suited to functionalization. Among others, these compounds show a strong dependency on the relative positioning of the hetero‐atoms within the ring system, a modulation control rendered possible by the insertion of the boron centres.
The urge to act: A comparison of active and passive socially responsible investment funds in the United States
Authors: Chen Xing , Scholtens Bert
Published: June 2018

Innovative finance vehicles are required to facilitate the transition towards a sustainable society. Here, we investigate two very successful innovations in the fund industry, namely index mutual funds and passively managed exchange traded funds (ETFs). We study socially responsible investment (SRI) funds in the United States and particularly focus on their financial performance, cost of investing and degree of active management. We do not find persuasive evidence that the actively managed funds perform better than their passively managed counterparts do. Furthermore, we find that some active SRI funds seem to operate as ‘closet indexers’ with a low degree of active management. We conclude that passively managed socially responsible funds have the potential to enrich the spectrum of financial products that may help advance the sustainability transition.
Loadbearing capacity of infill masonry walls considering the deformation‐based membrane effect
Authors: Schmitt Michael
Published: June 2018

According to currently valid codes, it is not possible to determine the loadbearing capacity of unreinforced infill walls considering the deformation‐based membrane effect by incorporating the exact support conditions. One reason for this is the lack of a validated calculation procedure, which in addition to the equilibrium conditions also realistically represents the compatibility conditions of these systems. In the present paper, therefore, a new non‐linear analytical calculation procedure is presented. The main focus of the analysis of walls subject to area loading is the incorporation of the support conditions and thus the consideration of the deformation‐based membrane compressive force. Through generalised formulation and a standardised notation of the determination equations, different material behaviours and various support conditions can be taken into account with few parameters. On the action side, both lighter loading like wind loads and heavier loading like explosion loads can be considered. Through the implementation of the partial factor concept, it is possible to comply with the requirements of European codes and thus ensure the applicability of the analysis model.
Proposal for the simplified design of basement walls under lateral earth pressure
Authors: Mazur René , Purkert Benjamin , Graubner Carl‐Alexander , Förster Valentin
Published: June 2018

This paper deals with the design of basement walls subjected to lateral earth pressure. The current simplified calculation method according to DIN EN 1996‐3/NA only covers active earth pressure, which is the lower limiting value of the earth pressure. Designing according to DIN EN 1996‐1‐1/NA, higher coefficients of earth pressure (like earth pressure at rest) can be considered, with an additional verification of the shear resistance being necessary. This paper presents a theoretical model, which forms the basis for an analytical derivation of the loadbearing capacity, and explains the required minimum values of the acting normal force to ensure sufficient resistance to cover bending and shear. Based on these results, a simplified equation is proposed for the determination of the required minimum normal force, based on the design according to DIN EN 1996‐3/NA and providing identical values in case of an earth pressure coefficient of 1/3. The required minimum load resulting from this approach fulfils the described requirement to cover bending and shear. The presented solution is verified and the conditions for application are defined. Finally, the minimum required normal forces are evaluated and tabulated for common cases relevant to building practice.
Help students with job‐related skills
Authors: Hamblet Elizabeth C.
Published: June 2018

In my most recent article, I wrote about ways to help make sure the career services office makes things accessible to students in a general way (see April 2018 issue). Another way disability services offices can be helpful to students and the career services office is to collaborate to help students learn job‐related skills.
Medical students choose between residency placement, accommodations
Authors: Sutton Halley
Published: June 2018

Less than 3 percent of medical students with disabilities seek accommodations, according to a report from the Association of American Medical Colleges and the University of California, San Francisco, School of Medicine.
P‐N Bridged Dinuclear Rh‐METAMORPhos Complexes: NMR and Computational Studies
Authors: Patureau Frederic W. , Groß Jessica , Ernsting Jan Meine , van Wüllen Christoph , Reek Joost N. H.
Published: June 2018

Sulfonamido‐phosphoramidites are known to form six‐membered ring Rh‐P‐N‐Rh‐P‐N‐ dinuclear complexes. Apart from a single X‐ray structure, little is known about their three dimensional structure in solution. This study proposes a 31P, 15N and 103Rh NMR investigation of the question, as a well as a DFT study. The AA′MM′XX′ 6 spin system of the corresponding 15N‐enriched dinuclear complex is notably described.
Interactions Between Hammer Mill Crushing Variables and Malaxation Time During Continuous Olive Oil Extraction
Authors: Polari Juan J. , Garcí‐Aguirre David , Olmo‐García Lucía , Carrasco‐Pancorbo Alegría , Wang Selina C.
Published: June 2018

Hammer mill crushing variables and malaxation time are studied through a two‐level factor factorial experimental design in order to assess the impact of these parameters and their interactions on olive oil extraction efficiency, overall quality, and minor components composition. Extraction efficiency is mainly affected by the interaction between hammer mill grid size and malaxation time; higher yields are obtained when smaller grid sizes are combined with longer malaxation times. Regarding quality parameters and volatile compounds, the main effect is caused by malaxation time. Phenolic compounds are affected by all the studied parameters, hammer mill grid size has the highest impact on their final concentration in the oil. The results show that the effect of malaxation time on the studied variables is conditioned by the crushing parameters used during paste preparation.

Practical Applications: Traditionally, the impact of processing variables on olive oil composition has been studied following a one‐variable‐at‐a‐time approach. A factor factorial experimental design allows the interactions among crushing conditions and malaxation time to be determined, as well as the individual contributions to extraction efficiency and minor components composition of these variables. Considering a more holistic approach to the study of olive oil extraction might provide processors with a wider spectrum of tools to maximize both yield and quality during olive oil processing.

Interaction of grid size, rotor speed, and malaxation time during olive oil extraction affects extraction efficiency, volatiles, and phenolics.
Development of a low flow‐resistive charged nanoporous membrane in a microchip for fast electropreconcentration
Authors: Chun Honggu
Published: June 2018

A nanoporous poly‐(styrene sulfonate) (poly‐SS) membrane was developed for fast and selective ion transport in a microfluidic chip. The poly‐SS membrane can be photopolymerized in‐situ at arbitrary location of a microchannel, enabling integrated fluidics design in the microfluidic chip. The membrane is characterized by a low hydraulic resistance and a high surface charge to maximize the electroosmotic flow and charge selectivity. The membrane characteristics were investigated by charge‐selective electropreconcentration method. Experimental results show membranes with various percentages of poly‐SS are able to concentrate anions (fluorescein and TRITC‐labeled BSA). The anion‐selective electropreconcentration process is stable and 26‐times faster than previously reported poly‐AMPS (2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid) based system. The electropreconcentration was also demonstrated to depend on the sample valency and buffer concentration.
Hydrogen Production from the Decomposition of Formic Acid over Carbon Nitride‐Supported AgPd Alloy Nanoparticles
Authors: Deng Qing‐Fang , Xin Jian‐Jiao , Ma Shang‐Kun , Cui Feng‐Juan , Zhao Zhen‐Long , Jia Li‐Hua
Published: June 2018

Highly dispersed bimetallic AgPd alloy nanoparticles with various ratios have been supported on carbon nitride by using a co‐reduction method and then tested for catalytic dehydrogenation of formic acid without base addictive. It was found that the activity of the catalyst depended directly on the AgPd ratios of the catalyst and the reaction temperature. The Ag1Pd2/CN catalyst exhibited excellent catalytic activity for hydrogen generation from formic acid with the initial TOF of 621 h−1 at 348 K. The synergetic interaction between the bimetallic AgPd nanoparticles and the carbon nitride support, the AgPd ratio and the dispersion of AgPd nanoparticles on the support contribute to the high catalytic performance of the AgPd/CN catalysts.
Stylolitic limestone, the stone of choice for ancient sanctuaries and temples, southwestern Peloponnese, Greece
Authors: Davis George H.
Published: June 2018

An Upper Cretaceous limestone was the stone of choice for classical Greek buildings and temples within the Pindos belt of the western Peloponnese. Knowledge of its properties at the Sanctuary of Zeus (Mt. Lykaion) is applied here to the Temple of Apollo Epikourios (Bassae) and the Arcadian Gate (Messene). Because of severe contortion and weathering, it was previously concluded that this bedrock was not the stone used at Bassae. Overlooked was the presence and weathered condition of its pervasive stylolites, which are closely spaced (cm‐scale) brain‐suture‐like surfaces resembling bedding laminae along which calcite dissolves and clay residue accumulates. The stylolites convey a false impression that the limestone is thin bedded and prone to splitting. Stylolites form as a response to stress during burial compaction and/or tectonic compression. Released calcium carbonate reprecipitates as calcite veins. The presence of the clay residue accounts for the severely weathered condition of outcrops and blocks. The suitability of this stone as a building material derives from cohesion acquired through bonding of interlocking stylolites and sealing by calcite veins. Its underdeveloped jointing explains how the megablock lintel of the Messene gate was geologically available. Opportunities are presented to evaluate stylolites at other geologically suitable archaeological sites.
Geochronology, petrogenesis, and tectonic implications of the Early Permian volcanic rocks in the northern margin of the North China Craton
Authors: Li Jialiang , Zhou Zhiguang , Wu Chen , Wang Yuegu , Wang Guosheng , Liu Changfeng , Liu Tong , Xu Wentao , Wu Jiangwei
Published: June 2018

We present new zircon U–Pb ages, geochemical data on the Late Palaeozoic volcanic rocks of the Suji and Dahongshan formations, which are exposed in the Plate Marginal Orogenic Belt along the northern margin of the North China Craton. Our aim is to constrain the petrogenesis, tectonic setting of volcanic rocks, and to address the late stage tectonic evolution of the Paleo‐Asian Ocean. Lithologically, the Suji and Dahongshan formations present the main rock association with basaltic andesite, andesite, dacite, rhyolite, and tuff. New zircon U–Pb dating results suggest that the volcanic rocks formed during 280–261 Ma and 277–267 Ma, respectively. Geochemically, these volcanic rocks belong to the low‐K tholeiitic to high‐K calc‐alkaline series and are characterized by highly enriched light rare earth elements, K, Rb, Ba; depleted Nb, Ta, Ti; and highly negative Eu anomalies, very similar to that of the continental arc magmatism. These data, together with geological field investigations, suggest that the Early Permian volcanic rocks from Suji and Dahongshan formations were related to southward flat subduction of the Paleo‐Asian Ocean beneath the northern margin of the North China Craton. Therefore, these volcanic rocks were interpreted as Andean‐style continental margin arc magmatism. This also indicates that the final collision between the North China Craton and the Siberian Craton did not occur until the Early Permian.
Numerical study of the hydrodynamics and heat transfer characteristics of liquid–liquid Taylor flow in microchannel
Authors: Vivekanand S.V.B. , Raju V.R.K.
Published: June 2018

A numerical study of an oil–water Taylor flow is presented in this paper to explore its flow and heat transfer characteristics. Due to the large surface area to volume ratio in narrow channels, using slug flows, high heat and mass transfer rates could be achieved. Sound knowledge of the underlying physics of slug flow is required for the practical design of microfluidic devices. In this study, hydrodynamics and heat transfer characteristics of dispersed oil droplets flowing inside a vertically upward circular microchannel (D = 0.1 mm) with water being the carrier phase have been explored numerically. ANSYS Fluent was employed to capture the liquid–liquid interface using volume of fluid method. Two different boundary conditions were considered in the present study. First, an isothermal wall of 373 K and later a constant wall heat flux (420 kW/m2) were, respectively, prescribed over the wall of the microchannel. The numerical code was validated against the results available in the literature, and the significant results in the form of pressure drop and heat transfer rates have been discussed. A considerable increase in Nusselt number, up to 180% and 210%, was observed with the oil–water slug flow in contrast to the liquid‐only single‐phase flow inside the microchannel for isothermal and constant wall heat flux conditions, respectively.
Differentiation of stem cells from apical papilla into neural lineage using graphene dispersion and single walled carbon nanotubes
Authors: Simonovic Jelena , Toljic Bosko , Nikolic Nadja , Peric Mina , Vujin Jasna , Panajotovic Radmila , Gajic Rados , Bekyarova Elena , Cataldi Amelia , Parpura Vladimir , Milasin Jelena
Published: June 2018

Stem cell‐based therapies are considered a promising treatment modality for many medical conditions. Several types of stem cells with variable differentiation potentials have been isolated from dental tissues, among them stem cells from apical papilla (SCAP). In parallel, new classes of biocompatible nanomaterials have also been developed, including graphene and carbon nanotube‐based materials. The aim of the study was to assess whether graphene dispersion (GD) and water‐soluble single walled carbon nanotubes (ws‐SWCNT), may enhance SCAPs capacity to undergo neural differentiation. SCAPs cultivated in neuroinductive medium supplemented with GD and ws‐SWCNT, separately and in combination, were subjected to neural marker analysis by real‐time polymerase chain reaction (neurofilament medium [NF‐M], neurogenin‐2 [ngn‐2], β III‐tubulin, microtubule‐associated protein 2) and immunocytochemistry (NeuN and β III‐tubulin). GD, ws‐SWCNT, and their combination, had neuro‐stimulatory effects on SCAPs, as judged by the production of neural markers. Compared to cells grown in nanomaterial free medium, cells with GD showed higher production of B3T, cells with ws‐SWCNT had higher production of ngn‐2 and NF‐M, while the combination of nanomaterials gave similar levels of both B3T and NF‐M as the neuroinductive medium alone, but with the finest neuron‐like morphology. In conclusion, GD and ws‐SWCNT seem to enhance neural differentiation of SCAP. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2653–2661, 2018.
Partitioning the edge set of a hypergraph into almost regular cycles
Authors: Bahmanian Amin , Haghshenas Sadegheh
Published: June 2018

A cycle of length t in a hypergraph is an alternating sequence of distinct vertices and distinct edges so that (with ). Let be the λ‐fold n‐vertex complete h‐graph. Let be a hypergraph all of whose edges are of size at least h, and . In order to partition the edge set of into cycles of specified lengths , an obvious necessary condition is that . We show that this condition is sufficient in the following cases.

.

, .

, , .

In (R2), we guarantee that each cycle is almost regular. In (R3), we also solve the case where a “small” subset L of edges of is removed.
Cover Image, Volume 93, Issue 7
Authors: Zhu Mimi , Fuks Preston , Carta Giorgio
Published: June 2018

The cover image, by Mimi Zhu et al., is based on the Research Article Protein adsorption in anion exchange resins ‐ effects of polymer grafting, support structure porosity, and protein size, DOI: 10.1002/jctb.5410.

image
Highly edge‐connected factors using given lists on degrees
Authors: Akbari Saieed , Hasanvand Morteza , Ozeki Kenta
Published: June 2018

Let G be a 2k‐edge‐connected graph with and let for every . A spanning subgraph F of G is called an L‐factor, if for every . In this article, we show that if for every , then G has a k‐edge‐connected L‐factor. We also show that if and for every , then G has a k‐edge‐connected L‐factor.
Etiology of viral respiratory infections in Northern Lao People's Democratic Republic
Authors: Snoeck Chantal J. , Ponghsavath Valy , Luetteke Nina , Kaufmann Sabine , Sausy Aurélie , Samountry Bounthome , Jutavijittum Prapan , Weber Bernard , Muller Claude P.
Published: June 2018

In Lao People's Democratic Republic (PDR), acute respiratory infections overburden the health care system, but viral etiology, genetic diversity, and seasonality, especially in light of the introduction of influenza vaccination in the country, are poorly understood. From August 2010 to April 2011, 309 outpatients were recruited at the Luang Prabang Provincial Hospital covering highland Lao communities. Nasopharyngeal swabs were screened for the presence of 13 respiratory viruses. At least one virus was detected in 69.6% and dual/triple viral infections in 12.9%/1.9% of the patients. Influenza A and B viruses combined were the most frequently detected pathogens, followed by human adenovirus and respiratory syncytial virus (RSV). The other viruses were detected in less than 10% of the patients. Phylogenetic analyses on a representative set of RSV strains revealed that, while otherwise very rare, the RSV‐B CB1/THB genotype cocirculated with other common genotypes. A single wave of influenza virus and RSV activity was observed during the rainy season, providing further support to influenza vaccination before the onset of the rains. This study provides recommendations for influenza vaccination that still needs optimization and highlights the need for revised guidelines for treatment and prevention of respiratory infections in Lao PDR, as well as for increased surveillance efforts.
Isolation, identification, and characterization of Ustilaginoidea virens from rice false smut balls with high ustilotoxin production potential
Authors: Lin Xiaoyan , Bian Yingfang , Mou Renxiang , Cao Zhaoyun , Cao Zhenzhen , Zhu Zhiwei , Chen Mingxue
Published: June 2018

Ustilaginoidea (U.) virens grows on rice grains and leads to significant rice yield losses in most of the major rice producing areas. Meanwhile, ustiloxins produced by U. virens are a serious hazard to human health and ecological safety of farmlands. The other key point is that ustiloxins have been regarded as a novel resource with their potential in the treatment of cancers. There is no better way to extract ustiloxins than from pure culture of the high ustilotoxin‐producing strains. U. virens has become a key research organism. However, due to the presence of some interference components, it is a certain difficulty in the successful isolation of the strain from the false smut balls. We present here a detailed study based on the separation, screening and identification of high ustiloxins‐producing strains of U. virens. Through this study, we got a satisfactory success rate of separation and provided a good solution to the problem of separation. At the same time, this study provides quality resources for researchers interested in ustiloxins as anticancer agents.
Novel rabbit model of moderate knee contracture induced by direct capsular damage
Authors: Hazlewood David , Feng Yi , Lu Qinghua , Yang Xinmai , Wang Jinxi
Published: June 2018

The treatment of joint contracture continues to represent a challenging problem in orthopedic surgery and rehabilitation medicine. Existing animal models of knee contracture for evaluating new treatments are mostly created by extensive joint tissue damage with Kirschner‐wire immobilization which requires a second surgery to remove Kirschner‐wires. This study aimed to develop a less invasive rabbit model of moderate knee contracture through a single surgery. Skeletally mature New Zealand White rabbits had their right knee operated to create surgical damage to the posterior capsule under direct visualization. Operated knees were then held in a flexed position by suturing the superficial flexion muscles with absorbable sutures. The flexion contracture (net extension loss) was determined by comparing the extension angles between the operated and non‐operated knees from 8 to 24 weeks post‐surgery. The flexion contracture of the operated knees was significantly greater (p < 0.01/0.001) than the non‐operated knees at each weekly measurement. The mean flexion contractures were 22° at 8 weeks, 19° at 16 weeks, and 18° at 24 weeks. No significant differences in the severity of flexion contracture were observed between 8‐week and each of the following weeks, suggesting that the flexion contracture was essentially stabilized by 8 weeks post‐surgery. Histopathologic analyses demonstrated intra‐articular and peri‐articular scar formation. This less invasive rabbit model of moderate knee contracture is more quickly established through a single surgery with lower risk of surgical complications compared to the previously reported invasive models, and could be an alternative animal model for joint contracture research. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2687–2695, 2018.
Role of maturity stages and modified‐atmosphere packaging on the quality attributes of cornelian cherry fruits (Cornus mas L.) throughout shelf life
Authors: Yarılgaç Tarık , Kadim Hayrullah , Ozturk Burhan
Published: June 2018

BACKGROUND

A study was conducted to determine the effects of modified‐atmosphere packaging (MAP) treatments on fruit quality attributes and bioactive compounds of cornelian cherry fruits (Cornus mas L.) harvested at two different maturity stages – maturity (M): M‐1, skin red color <10%; M‐2, skin red color >90% – throughout the shelf life. Fruits were stored at 0 ± 0.5 °C and 90 ± 5% relative humidity (RH) for 30 days, and then kept at 22 ± 0.5 °C and 80 ± 5% RH over 3 days for shelf life.

RESULTS

In the measurements performed at harvest, MS‐2 fruits had significantly greater respiration rate, soluble solids content, acidity, anthocyanin, flavonoids, and phenolics and significantly lower ethylene productions, firmness, L*, chroma, and hue angle values than MS‐1 fruits. In the last measurement period, MAP‐treated fruits had significantly greater firmness, total flavonoids, and total phenolics and significantly lower respiration rates, ethylene productions, and decay rates than the untreated fruits. While color parameters of MS‐2 fruits were significantly lower than the color values of MS‐1 fruits, they had greater vitamin C and anthocyanin contents.

CONCLUSION

It was concluded that the cornelian cherry fruits harvested at MS‐2 stage of maturity and preserved in MAP better maintained quality attributes throughout their shelf life. © 2018 Society of Chemical Industry
Findings of OCT‐angiography compared to fluorescein and indocyanine green angiography in central serous chorioretinopathy
Authors: Min Jing‐Yu , Lv Yanan , Yu Suqin , Gong Yuan‐Yuan
Published: June 2018

Purpose

The present study analyzed the appearances of optical coherence tomography angiography (OCTA) in patients with central serous chorioretinopathy (CSC) based on fluorescein angiography (FA) and indocyanine green angiography (ICGA).

Method

In the current case series, 54 eyes of 50 patients diagnosed as CSC were evaluated retrospectively. OCTA, FA, and ICGA were performed on each patient. Two trained observers examined the OCTA images independently to confirm and compare the choriocapillary appearance with that on FA/ICGA. Also, the leakage of vessels on FA, perfusion of choroidal blood flow on ICGA, blood flow density, and vascular morphology on OCTA, as well as, the effect of serous retinal detachment (SRD) on imaging were observed. Furthermore, the image findings of contralateral eyes were included.

Results

47/54 eyes (corresponding to 43 patients in 50 patients) were finally diagnosed with CSC that presented a leakage on FA and dilated vessels on ICGA, and the corresponding areas could be recognized on OCTA. However, in some of the cases (15 eyes, 31.9%), a portion of the leakage lesion on FA did not overlap completely with that on OCTA. On the OCTA B‐scan, six eyes did not show a choriocapillary flow signal under subretinal fluid (SRF) with a median SRD height of 485 µm, despite the dilated vessels on ICGA. Approximately, 21 contralateral eyes without SRD and leakage presented dilated vessels on ICGA; however, only 13 eyes could be recognized on OCTA. In addition, seven eyes presented CSC on FA/ICGA but manifested explicit abnormal vascularization beneath the retinal pigment epithelium (RPE) on OCTA.

Conclusion

FA/ICGA remains the gold standard for the diagnosis of CSC and cannot be completely replaced by OCTA. However, in some cases displaying hot‐spots CNV, OCTA can contribute toward a definite diagnosis. The SRD height may exert a shielding effect on the choriocapillary flow signals on OCTA. Lasers Surg. Med. 50:987–993, 2018. © 2018 Wiley Periodicals, Inc.
Impact of Cationic Charge Density and PEGylated Poly(amino acid) Tercopolymer Architecture on Their Use as Gene Delivery Vehicles. Part 1: Synthesis, Self‐Assembly, and DNA Complexation
Authors: Ulkoski David , Scholz Carmen
Published: June 2018

The interaction of PEGylated poly(amino acid)s with their biological targets depends on their chemical nature and spatial arrangement of their building blocks. The synthesis, self‐assembly, and DNA complexation of ABC terblock copolymers consisting of poly(ethylene glycol), (PEG), poly(l‐lysine), and poly(l‐leucine), are reported. Block copolymers are produced by a metal‐free, living ring‐opening polymerization of respective amino acid N‐carboxyanhydrides using amino‐terminated PEG as macroinitiator: (PEG‐b‐p(l‐Lys)x‐b‐p(l‐Leu)y, PEG‐b‐p(l‐Leu)x‐b‐p(l‐Lys)y, and PEG‐b‐p((l‐Lys)x‐co‐p(l‐Leu)y). Sizes of self‐assembled nanoparticles depend on the formation method. The nanoprecipitation method proves useful for copolymers with the poly(l‐lysine) block protected as trifluoroacetate, effective diameters range between 92 and 132 nm, while direct dissolution in distilled water is suitable for the deprotected copolymers, yielding effective diameters between 52 and 173 nm. Critical micelle concentration (CMC) analyses corroborate particle size analyses and show a distinct impact of the molecular architecture; the lowest CMC (8 µg mL−1) is observed when the poly(l‐leucine) segment forms the C‐block and the hydrophilic, disassembly driving poly(l‐lysine) segment is short. DNA complexation, evaluated by gel motility and RiboGreen analyses, depends strongly on the molecular architecture. A more efficient DNA complexation is observed when poly(l‐lysine) and poly(l‐leucine) form individual blocks as opposed to them forming a copolymer.
Changes in dominant Escherichia coli and antimicrobial resistance after 24 hr in fecal matter
Authors: Barrera Sofía , Cardenas Paul , Graham Jay P. , Trueba Gabriel
Published: June 2018

Intestinal bacteria carry antimicrobial resistance (AMR) genes in mobile genetic elements which have the potential to spread to bacteria in other animal hosts including humans. In fecal matter, Escherichia coli can continue to multiply for 48 hr after being excreted, and in certain environments, E. coli survive long periods of time. It is unclear the extent to which AMR in E. coli changes in the environment outside of its host. In this study, we analyzed changes in the population structure, plasmid content, and AMR patterns of 30 E. coli isolates isolated from 6 chickens (cloacal swabs), and 30 E. coli isolates from fecal samples (from the same 6 chickens) after 24 hr of incubation. Clonality of isolates was screened using the fumC gene sequence and confirmed in a subset of isolates (n = 14) by multi‐locus sequence typing. Major shifts in the population structure (i.e., sequence types) and antibiotic resistance patterns were observed among the numerically dominant E. coli isolates after 24 hr. Four E. coli clones isolated from the cloaca swabs and the corresponding fecal samples (after 24 hr incubation) showed different antibiotic resistance patterns. Our study reveals that fecal matter in the environment is an intermediate habitat where rapid and striking changes occur in E. coli populations and antibiotic resistance patterns.
Succession of embryonic and the intestinal bacterial communities of Atlantic salmon (Salmo salar) reveals stage‐specific microbial signatures
Authors: Lokesh Jep , Kiron Viswanath , Sipkema Detmer , Fernandes Jorge M.O. , Moum Truls
Published: June 2018

Host‐associated microbiota undergoes a continuous transition, from the birth to adulthood of the host. These developmental stage‐related transitions could lead to specific microbial signatures that could impact the host biological processes. In this study, the succession of early‐life and intestinal bacterial communities of Atlantic salmon (starting from embryonic stages to 80‐week post hatch; wph) was studied using amplicon sequencing of 16S rRNA. Stage‐specific bacterial community compositions and the progressive transitions of the communities were evident in both the early life and the intestine. The embryonic communities showed lower richness and diversity (Shannon and PD whole tree) compared to the hatchlings. A marked transition of the intestinal communities also occurred during the development; Proteobacteria were dominant in the early stages (both embryonic and intestinal), though the abundant genera under this phylum were stage‐specific. Firmicutes were the most abundant group in the intestine of late freshwater; Weissella being the dominant genus at 20 wph and Anaerofilum at 62 wph. Proteobacteria regained its dominance after the fish entered seawater. Furthermore, LEfSe analysis identified genera under the above ‐ mentioned phyla that are significant features of specific stages. The environmental (water) bacterial community was significantly different from that of the fish, indicating that the host is a determinant of microbial assemblage. Overall the study demonstrated the community dynamics during the development of Atlantic salmon.
SERS sensing of perampanel with nanostructured arrays of gold particles produced by pulsed laser ablation in water
Authors: Santoro Marco , Fazio Enza , Trusso Sebastiano , Tommasini Matteo , Lucotti Andrea , Saija Rosalba , Casazza Marina , Neri Fortunato , Ossi Paolo Maria
Published: June 2018

Noble metal nanoparticles (NPs) are among the most extensively studied colloidal systems, due to their surface plasmon resonances (SPR) of interest for biological sensing. We report here the synthesis of Au nanoparticles as water‐based colloids by nanosecond (τ = 5 ns) and picosecond (τ = 6 ps) pulsed laser ablation at the fixed fluence of 1.5 J/cm2 (λ = 532 nm) and different irradiation times (20 minutes, ns irradiations; 5 minutes, ps irradiations). Both ns and ps ablation lead to the synthesis of highly stable and chemically pure NPs. ps pulses allow synthesizing in remarkably short times (few minutes) smaller NPs with a narrower size distribution than using ns pulses. The surface‐enhanced Raman scattering (SERS) activity of Au NPs produced by ps ablation was tested, obtaining the first SERS spectrum of the new generation antiepileptic drug perampanel, whose clinical interest is relevant.
Risk factors for osteoporosis in chronic inflammatory demyelinating polyradiculoneuropathy
Authors: Kim Seung Woo , Choi Young‐Chul , Kim Seung Min , Shin Ha Young
Published: June 2018

Introduction: Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) patients possess multiple risk factors for osteoporosis, but few studies have evaluated bone mineral density (BMD) in CIDP patients. Methods: We retrospectively compared the BMD of CIDP patients with that of normal controls, and evaluated the clinical factors associated with osteoporosis. Results: Total BMD was lower in CIDP patients than in normal controls (P = 0.017). In a comparison of 16 osteoporotic CIDP patients with 25 non‐osteoporotic patients, the cumulative prednisolone dose was lower (P = 0.022) and the duration from disease onset to BMD measurement was shorter (P = 0.014) in osteoporotic patients than in non‐osteoporotic patients. Function, as measured by modified Rankin scale score within 3 years of the BMD measurement, was worse in osteoporotic than in non‐osteoporotic patients (P = 0.008). Discussion: BMD in CIDP patients was significantly lower than in normal controls. Functional status rather than cumulative steroid dose was associated with osteoporosis. Muscle Nerve 58: 407–412, 2018
Comment on the paper “Heat and mass transfer in unsteady MHD slip flow of Casson fluid over a moving wedge embedded in a porous medium in the presence of chemical reaction: Numerical solutions using Keller‐Box method, Imran Ullah, Ilyas Khan, Sharidan Shafie, Numerical Methods for Partial Differential Equations, November 2017, https://doi.org/10.1002/num.22221”
Authors: Pantokratoras Asterios
Published: June 2018

The present comment concerns some doubtful results included in the above paper.