bluuebunny/crossref_metadata_2025 huggingface dataset:
Multi‐Photon Absorption in Metal–Organic Frameworks
Authors: Medishetty Raghavender , Nemec Lydia , Nalla Venkatram , Henke Sebastian , Samoć Marek , Reuter Karsten , Fischer Roland A.
Published: September 2017

Multi‐photon absorption (MPA) is among the most prominent nonlinear optical (NLO) effects and has applications, for example in telecommunications, defense, photonics, and bio‐medicines. Established MPA materials include dyes, quantum dots, organometallics and conjugated polymers, most often dispersed in solution. We demonstrate how metal–organic frameworks (MOFs), a novel NLO solid‐state materials class, can be designed for exceptionally strong MPA behavior. MOFs consisting of zirconium‐ and hafnium‐oxo‐clusters and featuring a chromophore linker based on the tetraphenylethene (TPE) molecule exhibit record high two‐photon absorption (2PA) cross‐section values, up to 3600 GM. The unique modular building‐block principle of MOFs allows enhancing and optimizing their MPA properties in a theory‐guided approach by combining tailored charge polarization, conformational strain, three‐dimensional arrangement, and alignment of the chromophore linkers in the crystal.
Spin‐State‐Controlled Photodissociation of Iron(III) Azide to an Iron(V) Nitride Complex
Authors: Andris Erik , Navrátil Rafael , Jašík Juraj , Sabenya Gerard , Costas Miquel , Srnec Martin , Roithová Jana
Published: September 2017

The generation of iron(V) nitride complexes, which are targets of biomimetic chemistry, is reported. Temperature‐dependent ion spectroscopy shows that this reaction is governed by the spin‐state population of their iron(III) azide precursors and can be tuned by temperature. The complex [(MePy2TACN)Fe(N3)]2+ (MePy2TACN=N‐methyl‐N,N‐bis(2‐picolyl)‐1,4,7‐triazacyclononane) exists as a mixture of sextet and doublet spin states at 300 K, whereas only the doublet state is populated at 3 K. Photofragmentation of the sextet state complex leads to the reduction of the iron center. The doublet state complex photodissociates to the desired iron(V) nitride complex. To generalize these findings, we show results for complexes with cyclam‐based ligands.
Polymer nanogenerators: Opportunities and challenges for large‐scale applications
Authors: Wang Aurelia Chi , Wu Changsheng , Pisignano Dario , Wang Zhong Lin , Persano Luana
Published: September 2017

Technologies for energy harvesting from objects in motion are gaining a continuously increasing interest to directly power wearable electronics, sensors, and wireless transmitters. New networks where things will be uniquely identified and interconnected will require key enabling technologies, particularly cheap, flexible generators of renewable energy, conformable to any solid surface, to power independently individual objects and data transmission. Polymer‐based nanogenerators (PNGs), capable of converting mechanical energy into electricity, have exact features to fulfill these requirements. This article highlights advances in PNGs with focus on material chemistries and geometrical features, device design strategies, and performances. Representative examples of applications which show large‐scale capability are reported. Concluding sections summarize the key challenges and the commercialization perspectives of PNGs for use in real life applications. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45674.
Location‐aware targeted influence maximization in social networks
Authors: Su Sen , Li Xiao , Cheng Xiang , Sun Chenna
Published: September 2017

In this paper, we study the location‐aware targeted influence maximization problem in social networks, which finds a seed set to maximize the influence spread over the targeted users. In particular, we consider those users who have both topic and geographical preferences on promotion products as targeted users. To efficiently solve this problem, one challenge is how to find the targeted users and compute their preferences efficiently for given requests. To address this challenge, we devise a TR‐tree index structure, where each tree node stores users' topic and geographical preferences. By traversing the TR‐tree in depth‐first order, we can efficiently find the targeted users. Another challenge of the problem is to devise algorithms for efficient seeds selection. We solve this challenge from two complementary directions. In one direction, we adopt the maximum influence arborescence (MIA) model to approximate the influence spread, and propose two efficient approximation algorithms with
approximation ratio, which prune some candidate seeds with small influences by precomputing users' initial influences offline and estimating the upper bound of their marginal influences online. In the other direction, we propose a fast heuristic algorithm to improve efficiency. Experiments conducted on real‐world data sets demonstrate the effectiveness and efficiency of our proposed algorithms.
Coronary angiography with or without percutaneous coronary intervention in patients with hemophilia—Systematic review
Authors: Boehnel Christian , Rickli Hans , Graf Lukas , Maeder Micha T.
Published: September 2017

Objectives

We aimed to summarize the evidence for periprocedural and long‐term strategies to both minimize the bleeding risk and ensure sufficient anticoagulation and antiaggregation in hemophilia patients undergoing coronary angiography with or without percutaneous coronary interventions (PCI).

Background

Hemophilia patients undergoing coronary angiography and PCI are at risk of bleeding due to deficiency of the essential clotting factors VIII or IX combined with the need of peri‐interventional anticoagulation and antiaggregation and dual antiplatelet therapy (DAPT) after PCI.

Methods

We report on a patient with moderate hemophilia B undergoing single‐vessel PCI with administration of factor IX concentrate during the procedure and during the 1‐month DAPT period. In addition, a systematic review of patients (n = 54, mean age 58 ± 10 years) with hemophilia A (n = 45, 83%) or B (n = 9, 17%) undergoing coronary angiography with or without PCI is presented.

Results

Peri‐interventional factor substitution was performed in the majority (42 of 54, 78%) but not all patients. In 38 of 54 (70%) patients undergoing coronary angiography, PCI with balloon dilation (n = 5), bare metal (n = 31), or drug‐eluting stents (n = 2) was performed. For PCI unfractioned heparin (n = 24), low molecular weight heparin (n = 2), bivalirudin (n = 4), or no periprocedural anticoagulation at all (n = 8) were used. PCI was successful in all cases. After stenting, the majority (28 of 33; 85%) was treated with DAPT (median duration 1 month). Major periprocedural bleeding episodes occurred in 3 of 54 (6%) patients. Bleeding during follow‐up occurred in 11 of 54 (20%) patients.

Conclusions

Coronary angiography and PCI in patients with hemophilia are effective and safe when applying individualized measures to prevent bleeding.
Right ventricle outflow tract prestenting: In vitro testing of rigidity and corrosion properties
Authors: Cools Bjorn , Brown Stephen , Wevers Martine , Humbeeck Jan Van , Boshoff Derize , Verdonckt Cis , Gewillig Marc
Published: September 2017

Background

The aim of this study was to assess the resistance to compression (stiffness) of frequently used stents for right ventricular outflow tract prestenting. In addition, to assess the corrosion potential when different types of stent alloys come into contact with each other.

Method

Different stents were tested in vitro in various combinations at specialized metallurgic laboratories. A bench compression test was used to assess resistance to compression of singular and joined combinations of stents. Corrosion was evaluated by standardized electrochemical galvanic tests in physiological solutions at 37°C. Single stents and combinations of stents were evaluated over a period of 4–12 weeks.

Results

Relative stiffness of the stents Optimus/Andrastent XXL/Intrastent LD Max/8zig Cheatham‐Platinum, expressed as load per length to deform the stent for 1 mm at 22 mm was 100/104/161/190. Adding additional stents to a single stent significantly strengthened the joined couples (P < 0.001). The lowest galvanic corrosion rates (about 0.000001 mm/year) were observed for the joined CP‐Andrastent, Andra‐Sapien, and Andra‐SapienXT. The corrosion rate for coupled CP‐Sapien and CP‐SapienXT was somewhat higher (about 0.000003 mm/year). The materials with the highest corrosion rates resulted in material losses of, respectively, 17 and 24 µg/year, which is negligible over a lifetime.

Conclusion

Adding stents to a single stent significantly increases stiffness which will reduce the risk of metal fatigue failure. Corrosion of individual stents or stent combinations occurs, but is negligible over a human lifetime with low risk of biological effects. No mechanical integrity problems are thus expected as there is only 0.3% of the initial diameter of the struts of a stent that will be lost as a consequence of corrosion after 100 years.
η1‐Arene Complexes as Intermediates in the Preparation of Molecular Phosphorescent Iridium(III) Complexes
Authors: Esteruelas Miguel A. , Gómez‐Bautista Daniel , López Ana M. , Oñate Enrique , Tsai Jui‐Yi , Xia Chuanjun
Published: September 2017

Molecular phosphorescent heteroleptic bis‐tridentate iridium(III) emitters have been prepared via η1‐arene intermediates. In the presence of 4.0 mol of AgOTf, the complex [(IrCl{κ3‐N,C,N‐(pyC6HMe2py)})(μ‐Cl)]2 (1; pyC6H2Me2py=1,3‐di(2‐pyridyl)‐4,6‐dimethylbenzene) reacted with 9‐(6‐phenylpyridin‐2‐yl)‐9H‐carbazole (PhpyCzH) and 2‐phenoxy‐6‐phenylpyridine (PhpyOPh) to give [Ir{κ3‐N,C,N‐(pyC6HMe2py)}{κ3‐C,N,C′‐(C6H4pyCzH)}]OTf (2) and [Ir{κ3‐N,C,N‐(pyC6HMe2py)}{κ3‐C,N,C′‐(C6H4pyOPh)}]OTf (3). The X‐ray diffraction structures of 2 and 3 reveal that the carbazolyl and phenoxy substituents of the C,N,C′ ligand coordinate to the metal center to form an η1‐arene π bond. Treatment of 2 and 3 with KOtBu led to the deprotonation of the coordinated carbon atom of the η1‐arene group to afford the molecular phosphorescent [5t+4t′] heteroleptic iridium(III) complexes [Ir{κ3‐N,C,N‐(pyC6HMe2py)}{κ3‐C,N,C′‐(C6H4pyCz)}] (4) and [Ir{κ3‐N,C,N‐(pyC6HMe2py)}{κ3‐C,N,C′‐(C6H4pyOC6H4)}] (5). These complexes are green emitters that display short lifetimes and high quantum yields of 0.73 (4) and 0.87 (5) in the solid state.
Synthesis of Coordination Polymer Nanoparticles using Self‐Assembled Block Copolymers as Template
Authors: Weber Birgit
Published: September 2017

Nowadays there is a high demand in specialized functional materials, for example, for applications as sensors in biomedicine. For the realization of such applications, nanostructures and the integration in a composite matrix are indispensable. Coordination polymers and networks, for example, with spin crossover properties, are a highly promising family of switchable materials in which the switching process can be triggered by various external stimuli. An overview over different strategies for the synthesis of nanoparticles of such systems is given. A special focus is set on the use of block copolymer micelles as templates for the synthesis of nanocomposites. The block copolymer defines the final size and shape of the nanoparticle core. Additionally it allows a further functionalization of the obtained nanoparticles by variation of the polymer blocks and an easy deposition of the composite material on surfaces.
High‐Pressure Chemistry and the Mechanochemical Polymerization of [5]‐Cyclo‐p‐phenylene
Authors: Qiu Lili , Peña‐Alvarez Miriam , Taravillo Mercedes , Evans Paul J. , Darzi Evan R. , Jasti Ramesh , Burrezo P. Mayorga , López Navarrete Juan T. , Baonza Valentín G. , Casado Juan , Kertesz Miklos
Published: September 2017

Evidence for the surprising formation of polymeric phases under high pressure for conjugated nanohoop molecules was found. This paper represents one of the unique cases, in which the molecular‐level effects of pressure in crystalline organic solids is addressed, and provides a general approach based on vibrational Raman spectroscopy combining experiments and computations. In particular, we studied the structural and supramolecular chemistry of the cyclic conjugated nanohoop molecule [5]cyclo‐para‐phenylene ([5]CPP) under high pressures up to 10 GPa experimentally and up to 20 GPa computationally. The theoretical modeling for periodic crystals predicts good agreements with the experimentally obtained Raman spectra in the molecular phase. In addition, we have discovered two stable polymeric phases that arise in the simulation. The critical pressures in the simulation are too high, but the formation of polymeric phases at high pressures provides a natural explanation for the observed irreversibility of the Raman spectra upon pressure release between 6 and 7 GPa. The geometric parameters show a deformation toward quinonoid structures at high pressures accompanied by other deformations of the [5]CPP nanohoops. The quinonoidization of the benzene rings is linked to the systematic change of the bond length alternation as a function of the pressure, providing a qualitative interpretation of the observed spectral shifts of the molecular phase.
Study of Ultrasound Propagation and Cavitation Activity in a Packing Bed of Spherical Particles
Authors: Lesnik Sergey , Mettin Robert , Brenner Gunther
Published: September 2017

The application of ultrasonic cavitation in chemical processing is a widespread method to accelerate dissolution processes. In recycling technology, often bulk material is introduced into a reactor forming a packed bed of granular particles. Thereby, the cavitation activity at the material surfaces is of interest. In this numerical study, the packed bed is simplified by sphere packings of different arrangement and porosity. The ultrasound propagation model considers the effect of cavitation bubbles by a linearized damping ansatz. A strong sound scattering by the spheres is found for packings with low porosities, while the sphere arrangement is less important.
Haptic simulation of tissue tearing during surgery
Authors: Quesada C. , Alfaro I. , González D. , Chinesta F. , Cueto E.
Published: September 2017

We present a method for the real‐time, interactive simulation of tissue tearing during laparoscopic surgery. The method is designed to work at haptic feedback rates (ie, around 1 kHz). Tissue tearing is simulated under the general framework of continuum damage mechanics. The problem is stated as a general, multidimensional parametric problem, which is solved by means of proper generalized decomposition methods. One of the main novelties is the reduction of history‐dependent problems, such as damage mechanics, by resorting to an approach in which a reduced‐order field of initial damage values is considered as a parameter of the formulation. We focus on the laparoscopic cholecystectomy procedure as a general example of the performance of the method.
Inflammation: Treatment Progress and Limitations
Authors: Cascorbi Ingolf
Published: September 2017

There is an increasing understanding on the etiology of chronic immune‐mediated inflammatory diseases such as inflammatory bowel disease (IBD), psoriasis, or rheumatoid arthritis. Large consortia contributed to the elucidation of the genetics, for instance, of IBD identifying a number of genes involved in innate mucosal defense and immune tolerance (most prominent, e.g., NOD2) and other related processes. For a number of such diseases, common genetic susceptibility loci were identified, suggesting overlapping immune response pathways, although there is no causality of single genetic traits.2 In particular, the elucidation of main triggers of inflammation like tumor necrosis factor alpha (TNFα), integrins, specific cytokines like interleukin (IL)‐6 or IL‐23 launched the successful development of new pharmacological approaches, leading to a tremendous improvement of therapeutic outcomes.
Enhanced Trace Carbon Dioxide Capture on Heteroatom‐Substituted RHO Zeolites under Humid Conditions
Authors: Ke Quanli , Sun Tianjun , Wei Xiaoli , Guo Ya , Wang Shudong
Published: September 2017

Boron and copper heteroatoms were successfully incorporated into the frameworks of high‐silica RHO zeolite by adopting a bulky alkali‐metal–crown ether (AMCE) complex as the template. These heteroatom‐doped zeolites show both larger micropore surface areas and volumes than those of their aluminosilicate analogue. Proton‐type RHO zeolites were then applied for the separation of CO2/CH4/N2 mixtures, as these zeolites have weaker electric fields and, thus, lower heats of adsorption. The adsorption results showed that a balance between working capacity and adsorption heat could be achieved for these heteroatom‐doped zeolites. Ideal adsorbed solution theory predictions indicate that these zeolites should have high selectivities even for remarkably dilute sources of CO2. Finally, the heteroatom‐substituted zeolites, especially the boron‐substituted one, could be thermally regenerated rapidly at 150 °C after full hydration and maintained high regenerability for up to 30 cycles; therefore, they are potential candidates for trace CO2 removal under humid conditions.
A Green and Sustainable Route to Carbohydrate Vinyl Ethers for Accessing Bioinspired Materials with a Unique Microspherical Morphology
Authors: Rodygin Konstantin S. , Werner Irina , Ananikov Valentine P.
Published: September 2017

Synthesizing chemicals and materials from renewable sources is one of the main aims of modern science. Carbohydrates represent excellent renewable natural raw materials that are ecofriendly, inexpensive, and biologically compatible. A green procedure has been developed for the vinylation of carbohydrates by using readily available calcium carbide. Various carbohydrates were utilized as starting materials, resulting in mono‐, di‐, and tetravinyl ethers in high to excellent yields (81–92 %). The synthesized biobased vinyl ethers were utilized as monomers in free radical and cationic polymerizations. A unique combination of a smooth surface and intrinsic microcompartments was achieved in the synthesized materials. Two types of biobased materials were prepared involving microspheres and intrinsic hollow compartments in polymers. Scanning electron microscopy with built‐in ion beam cutting was applied to reveal the spatial hierarchical structures in 3D space.
Catalytic Upgrading of Ethanol to n‐Butanol: Progress in Catalyst Development
Authors: Wu Xianyuan , Fang Geqian , Tong Yuqin , Jiang Dahao , Liang Zhe , Leng Wenhua , Liu Liu , Tu Pengxiang , Wang Hongjing , Ni Jun , Li Xiaonian
Published: September 2017

Because n‐butanol as a fuel additive has more advantageous physicochemical properties than those of ethanol, ethanol valorization to n‐butanol through homo‐ or heterogeneous catalysis has received much attention in recent decades in both scientific and industrial fields. Recent progress in catalyst development for upgrading ethanol to n‐butanol, which involves homogeneous catalysts, such as iridium and ruthenium complexes, and heterogeneous catalysts, including metal oxides, hydroxyapatite (HAP), and, in particular, supported metal catalysts, is reviewed herein. The structure–activity relationships of catalysts and underlying reaction mechanisms are critically examined, and future research directions on the design and improvement of catalysts are also proposed.
Inbreeding depression is high in a self‐incompatible perennial herb population but absent in a self‐compatible population showing mixed mating
Authors: Voillemot Marie , Pannell John R.
Published: September 2017

High inbreeding depression is thought to be one of the major factors preventing evolutionary transitions in hermaphroditic plants from self‐incompatibility (SI) and outcrossing toward self‐compatibility (SC) and selfing. However, when selfing does evolve, inbreeding depression can be quickly purged, allowing the evolution of complete self‐fertilization. In contrast, populations that show intermediate selfing rates (a mixed‐mating system) typically show levels of inbreeding depression similar to those in outcrossing species, suggesting that selection against inbreeding might be responsible for preventing the transition toward complete self‐fertilization. By implication, crosses among populations should reveal patterns of heterosis for mixed‐mating populations that are similar to those expected for outcrossing populations. Using hand‐pollination crosses, we compared levels of inbreeding depression and heterosis between populations ofLinaria cavanillesii(Plantaginaceae), a perennial herb showing contrasting mating systems. TheSIpopulation showed high inbreeding depression, whereas theSCpopulation displaying mixed mating showed no inbreeding depression. In contrast, we found that heterosis based on between‐population crosses was similar forSIandSCpopulations. Our results are consistent with the rapid purging of inbreeding depression in the derivedSCpopulation, despite the persistence of mixed mating. However, the maintenance of outcrossing after a transition toSCis inconsistent with the prediction that populations that have purged their inbreeding depression should evolve toward complete selfing, suggesting that the transition toSCinL. cavanillesiihas been recent.SCinL. cavanillesiithus exemplifies a situation in which the mating system is likely not at an equilibrium with inbreeding depression.
The influence of forest regrowth on soil hydraulic properties and erosion in a semiarid region of Brazil
Authors: Leite Pedro A.M. , de Souza Eduardo S. , dos Santos Eduardo S. , Gomes Rafael J. , Cantalice José R. , Wilcox Bradford P.
Published: September 2017

Dryland tropical forests are important but little‐understood ecosystems. These landscapes are at risk globally because of accelerated deforestation and the consequent losses of hydrological functions. An example is the Caatinga shrublands in northeastern Brazil; these dry tropical forests are undergoing rapid change as the land is converted to cultivated cropland and pastureland and then often abandoned after the land is exhausted, allowing forests to regrow. In this study, we evaluated how these changes influence soil hydraulic properties and soil erosion in Caatinga landscapes, by examining four sites of different ages: a recently abandoned pasture, a young (7 years of regrowth) secondary forest, an intermediate (35 years of regrowth) secondary forest, and an older (more than 55 years) forest. Rainfall simulation was used to assess soil infiltrability and susceptibility to erosion. In addition, we determined hydrological conductivity in the field using the Beerkan method (Kfs) and collected samples for laboratory‐determined measurements (Ks). We found that infiltrability and Kfs values were progressively higher as time since land abandonment increased, whereas Ks values were not significantly different across sites. Infiltrability was approximately 2 times smaller than Ks and Kfs—possibly owing to the formation of soil crusts from raindrop impact. Soil erosion did not show a progressive improvement with forest age and was better explained by site characteristics, such as herbaceous cover and slope. In general, our results suggest that in Caatinga landscapes, more than 35 years is required for the recovery of soil hydraulic properties following land abandonment.
Diversity‐Oriented Synthesis of Carbohydrate Scaffolds through the Prins Cyclization of Differently Protected d‐Mannitol‐Derived Homoallylic Alcohols
Authors: Dubbu Sateesh , Vankar Yashwant D.
Published: September 2017

A diversity‐oriented synthesis of a variety of carbohydrate scaffolds, including sugar‐fused isochroman derivatives, bicyclic vinyl halide derivatives, fluorine‐substituted tetrahydropyrans, and a furan derivative, is reported. This was achieved through the Prins reaction of d‐mannitol‐derived homoallylic alcohols in which the allylic alcohol bears a different protecting group, leading to structural variation in the products. Some of the products were also converted into more functionalized scaffolds of wider utility and of possible biological importance. Appropriate mechanisms have been proposed to account for the product formation.
Offset analgesia: The role of peripheral and central mechanisms
Authors: Ligato D. , Petersen K.K. , Mørch C.D. , Arendt‐Nielsen L.
Published: September 2017

Background

Offset Analgesia (OA) can be evoked by a three‐heat‐stimulus train (T1‐T2‐T3), with T1 (5 s) and T3 (20 s) having the same temperature (e.g. 48 °C) and T2 (5 s) being slightly higher (1–3 °C). OA is defined as a disproportional pain reduction caused by the slight temperature decrease from T2 to T3. As the pain modulatory mechanisms behind OA are still poorly understood, the current study aimed to investigate the role of peripheral and central mechanisms by applying heat stimuli to the same location and to different unilateral and bilateral locations.

Method

Young healthy volunteers participated in the study. A ‘standard‐OA’ paradigm (48–49–48 °C) was applied to the non‐dominant volar forearm (T1–T2–T3 applied on the same location). ‘Unilateral‐OA’ trials were applied on three different locations of the non‐dominant volar forearm (the same dermatome). ‘Bilateral‐OA’ trials were applied by shifting T1–T2–T3 between dominant and non‐dominant volar forearms. A constant stimulus of 48 °C was applied as control for the evoked pain. The pain intensities were continuously recorded using an electronic visual analogue scale.

Results

The largest pain intensity reduction was reported for the ‘standard‐OA’ paradigm (p < 0.001) compared with the control stimulus. Both ‘Unilateral‐OA’ and ‘Bilateral‐OA’ trials caused a significant pain reduction (p < 0.05) compared with the control; however, the pain reduction was less than that evoked by ‘standard‐OA’ (p < 0.05).

Conclusion

This study showed that OA could be elicited when the stimuli were applied both to the same and to different locations (ipsi‐ and contralateral) indicating that peripheral as well as central mechanisms are involved in mediating OA.

Significance

This study investigated offset analgesia by applying thermal painful stimuli to the ipsi‐ and bilateral forearms in healthy subjects and found that both peripheral and central mechanisms seem to mediate offset analgesia.
Electrochemically Reduced Graphene Oxide for Forensic Electrochemistry: Detection of Cocaine and its Adulterants Paracetamol, Caffeine and Levamisole
Authors: Rocha Diego P. , Dornellas Rafael M. , Nossol Edson , Richter Eduardo M. , Silva Sidnei G. , Santana Mário H. P. , Munoz Rodrigo A. A.
Published: September 2017

This communication shows the improved performance of electrochemically‐reduced graphene oxide (ERGO) modified electrodes for the square‐wave voltammetric detection of cocaine (COC) and its main adulterants paracetamol (PAR), caffeine (CAF) and levamisole (LEV). The four compounds can be identified in a single voltammetric scan on the ERGO‐modified electrode with adequate resolution of peaks and increase in current (at least 2‐fold) in comparison with the unmodified electrode. Moreover, electrode fouling typically verified during the oxidation of CAF and LEV is eliminated. CAF and PAR were determined in a real COC sample and satisfactory recovery values were obtained (103 and 85 %, respectively).
A novel efficient hybrid DSMC–dynamic collision limiter algorithm for multiscale transitional flows
Authors: G Malaikannan , Kumar Rakesh , Chinnappan Arun Kumar
Published: September 2017

A new 2D parallel multispecies polyatomic particle–based hybrid flow solver is developed by coupling the Direct Simulation Monte Carlo (DSMC) method with a novel Dynamic Collision Limiter (DCL) approach to solve multiscale transitional flows. The hybrid DSMC‐DCL solver can solve nonequilibrium multiscale flows with length scales ranging from continuum to rarefied. The DCL method, developed in this work, dynamically assigns different number of collisions in cells, which is based on the local value of K‐S parameter such that the number of collisions per time step is limited in near‐equilibrium flow regions. Present hybrid solver uses the Kolmogorov‐Smirnov statistical test as the continuum breakdown parameter, based on which, the solution domain is decomposed into near‐equilibrium and nonequilibrium flow regions. Direct Simulation Monte Carlo is used where nonequilibrium flow regions are encountered, while the DCL method is used where flow regions are found to be in near‐equilibrium state. In this work, we have studied hypersonic flow of nitrogen over a blunt body with an aerospike and supersonic flow of argon through a micronozzle. The results obtained by the hybrid DSMC‐DCL solver are compared and shown to agree well with the experimental data and with those obtained from DSMC, with significant savings in the computational cost.
Momentum‐based approximation of incompressible multiphase fluid flows
Authors: Cappanera Loïc , Guermond Jean‐Luc , Herreman Wietze , Nore Caroline
Published: September 2017

We introduce a time stepping technique using the momentum as dependent variable to solve incompressible multiphase problems. The main advantage of this approach is that the mass matrix is time‐independent making this technique suitable for spectral methods. A level set method is applied to reconstruct the fluid properties such as density. We also introduce a stabilization method using an entropy‐viscosity technique and a compression technique to limit the flattening of the level set function. We extend our algorithm to immiscible conducting fluids by coupling the incompressible Navier‐Stokes and the Maxwell equations. We validate the proposed algorithm against analytical and manufactured solutions. Results on test cases such as Newton's bucket problem and a variation thereof are provided. Surface tension effects are tested on benchmark problems involving bubbles. A numerical simulation of a phenomenon related to the industrial production of aluminium is presented at the end of the paper.
Convergence acceleration of continuous adjoint solvers using a reduced‐order model
Authors: Kaminsky Andrew L. , Djeddi Reza , Ekici Kivanc
Published: September 2017

A novel acceleration technique using a reduced‐order model is presented to speed up convergence of continuous adjoint solvers. The acceleration is achieved by projecting to an improved solution within an iterative process solely using early solution results. This is achieved by forming basis vectors from early iteration adjoint solutions to perform model order reduction of the adjoint equations. The reduced‐order model of the adjoint equations is then substituted into the full‐order discretized governing equations to determine weighting coefficients for each basis vector. With these coefficients, a linear combination of the basis vectors is used to project to an improved solution. The method is applied to 3 inviscid quasi‐1D nozzle flow cases including fully subsonic flow, subsonic inlet to supersonic outlet flow, and transonic flow with a shock. Significant cost reductions are achieved for a single application as well as repeated applications of the convergence acceleration technique.
Organic solute transporter‐β (SLC51B) deficiency in two brothers with congenital diarrhea and features of cholestasis
Authors: Sultan Mutaz , Rao Anuradha , Elpeleg Orly , Vaz Frédéric M. , Abu‐Libdeh Bassam , Karpen Saul J. , Dawson Paul A.
Published: September 2017

Primary bile acid malabsorption is associated with congenital diarrhea, steatorrhea, and a block in the intestinal return of bile acids in the enterohepatic circulation. Mutations in the ileal apical sodium‐dependent bile acid transporter (ASBT; SLC10A2) can cause primary bile acid malabsorption but do not appear to account for most familial cases. Another major transporter involved in the intestinal reclamation of bile acids is the heteromeric organic solute transporter alpha‐beta (OSTα‐OSTβ; SLC51A‐SLC51B), which exports bile acid across the basolateral membrane. Here we report the first patients with OSTβ deficiency, clinically characterized by chronic diarrhea, severe fat soluble vitamin deficiency, and features of cholestatic liver disease including elevated serum gamma‐glutamyltransferase activity. Whole exome sequencing revealed a homozygous single nucleotide deletion in codon 27 of SLC51B, resulting in a frameshift and premature termination at codon 50. Functional studies in transfected cells showed that the SLC51B mutation resulted in markedly reduced taurocholic acid uptake activity and reduced expression of the OSTα partner protein. Conclusion: The findings identify OSTβ deficiency as a cause of congenital chronic diarrhea with features of cholestatic liver disease. These studies underscore OSTα‐OSTβ's key role in the enterohepatic circulation of bile acids in humans. (Hepatology 2017).
50 years of rational‐emotive and cognitive‐behavioral therapy: A systematic review and meta‐analysis
Authors: David Daniel , Cotet Carmen , Matu Silviu , Mogoase Cristina , Stefan Simona
Published: September 2017

Objective

Rational emotive behavior therapy (REBT), introduced by Albert Ellis in the late 1950s, is one of the main pillars of cognitive‐behavioral therapy. Existing reviews on REBT are overdue by 10 years or more. We aimed to summarize the effectiveness and efficacy of REBT since its beginnings and investigate the alleged mechanisms of change.

Method

Systematic search identified 84 articles, out of which 68 provided data for between‐group analyses and 39 for within‐group analyses.

Results

We found a medium effect size of REBT compared to other interventions on outcomes (d = 0.58) and on irrational beliefs (d = 0.70), at posttest. For the within‐group analyses, we obtained medium effects for both outcomes (d = 0.56) and irrational beliefs (d = 0.61). Several significant moderators emerged.

Conclusion

REBT is a sound psychological intervention. Directions for future studies are outlined, stemming from the limitations of existing ones.
Catalytic distillation for esterification of acetic acid with ethanol: promising SS‐fiber@HZSM‐5 catalytic packings and experimental optimization via response surface methodology
Authors: Deng Tao , Ding Jia , Zhao Guofeng , Liu Ye , Lu Yong
Published: September 2017

BACKGROUND

Catalytic distillation (CD) is considered a promising green chemical process for numerous catalytic esterification reactions. Rendering novel structured CD packings is particularly desirable but remains challenging.

RESULTS

A microfibrous‐structured HZSM‐5 solid acid catalyst is proposed as CD packing and its separation and esterification reaction efficiency for producing ethyl acetate from acetic acid and ethanol are demonstrated. Factorial design based on response surface methodology is employed for fast determination of optimum reaction conditions, which is working effectively and efficiently. Such structured catalyst packing is obtained by direct growth of zeolite onto the θ‐ring analogues shaped from a microfibrous‐structure consisting of 15 vol% 20 µm stainless‐steel‐fiber (SS‐fiber) and 85 vol% voidage.

CONCLUSION

The SS‐fiber@HZSM‐5 packing provides a unique combination of instantaneous distillation and desired catalytic properties with respect to stability, adequate acidic sites and high mass/heat transfer, and therefore works efficiently and effectively. High total (95.9%) and actual (90.9%) yields of ethyl acetate with 89.8% purity are achievable while the high CD efficiency was well‐preserved after at least 240 h over 30 consecutive batch runs. © 2017 Society of Chemical Industry
Bringing radical behaviorism to revolutionary Brazil and back: Fred Keller's Personalized System of Instruction and Cold War engineering education
Authors: Akera Atsushi
Published: September 2017

This article traces the shifting epistemic commitments of Fred S. Keller and his behaviorist colleagues during their application of Skinnerian radical behaviorism to higher education pedagogy. Building on prior work by Alexandra Rutherford and her focus on the successive adaptation of Skinnerian behaviorism during its successive applications, this study utilizes sociologist of science Karin Knorr Cetina's concept of epistemic cultures to more precisely trace the changes in the epistemic commitments of a group of radical behaviorists as they shifted their focus to applied behavioral analysis. The story revolves around a self‐paced system of instruction known as the Personalized System of Instruction, or PSI, which utilized behaviorist principles to accelerate learning within the classroom. Unlike Skinner's entry into education, and his focus on educational technologies, Keller developed a mastery‐based approach to instruction that utilized generalized reinforcers to cultivate higher‐order learning behaviors. As it happens, the story also unfolds across a rather fantastic political terrain: PSI originated in the context of Brazilian revolutionary history, but circulated widely in the U.S. amidst Cold War concerns about an engineering manpower(sic) crisis. This study also presents us with an opportunity to test Knorr Cetina's conjecture about the possible use of a focus on epistemic cultures in addressing a classic problem in the sociology of science, namely unpacking the relationship between knowledge and its social context. Ultimately, however, this study complements another historical case study in applied behavioral analysis, where a difference in outcome helps to lay out the range of possible shifts in the epistemic commitments of radical behaviorists who entered different domains of application. The case study also has some practical implications for those creating distance learning environments today, which are briefly explored in the conclusion.
Recent progress using the Staudinger ligation for radiolabeling applications
Authors: Mamat Constantin , Gott Matthew , Steinbach Jörg
Published: September 2017

The increasing application of positron emission tomography and single‐photon emission computer tomography in radiopharmacy and nuclear medicine has stimulated the development of a multitude of novel and versatile bioorthogonal conjugation techniques. Currently, there is particular interest in radiolabeling biologically active, high molecular weight compounds like peptides, proteins, or antibodies, but also for the labeling of small organic compounds. An enormous challenge in radiolabeling these biologically active molecules is that the introduction of radiohalogens like fluorine‐18 as well as various radiometals proceeds under harsh conditions, which could destroy the biomolecule. The Staudinger ligation is one of the most powerful bioorthogonal conjugation techniques. The reaction proceeds over wide temperature and pH ranges; an amide (peptide) bond is formed as the ligation unit, which minimizes distortion of the structure; no isomers are obtained; and the reaction proceeds without any metal catalyst. Due to this adaptability, this robust ligation type is a perfect candidate with a high potential for various applications in the field of radiopharmacy for the labeling of biomolecules under mild conditions. This review summarizes recent research concerning the implementation of the Staudinger ligation for radiolabeling applications.
Climate evolution and forcing during the last 40 ka from the oscillations in Apennine glaciers and high mountain lakes, Italy
Authors: Giraudi Carlo
Published: September 2017

The results of studies carried out on the variations of glaciers and lakes in the higher Apennines during the last 40 ka are considered for correlation with some climate forcing agents, e.g. changes in insolation, variations in origin of the air masses carrying moisture and North Atlantic events, acting both at regional and hemispheric scales. The origin of air masses was assessed using the Apennine equilibrium line altitude pattern, the presence of a quartz‐rich loess in the former glacial environment and the sedimentation rate of Sahara quartz in maar lakes. Temperature and humidity variations have been deduced from glacier expansions and retreats and lake oscillations. The data discussed in the paper show that variations in insolation have driven climatic changes in the Apennines for most of the considered time span, producing gradual changes that took place during periods lasting several thousand years. However, during some periods, insolation seems to have been of minor importance compared to variations in frequency and intensity of southern air currents, and to the influence of North Atlantic events. The data, as a whole, allow us to highlight the climatic evolution of the high Apennine mountains during the last 40k cal a BP.
An overview of genetically modified crop governance, issues and challenges in Malaysia
Authors: Andrew Johnny , Ismail Normaz Wana , Djama Marcel
Published: September 2017

The application of agricultural biotechnology attracts the interest of many stakeholders. Genetically modified (GM) crops, for example, have been rapidly increasing in production for the last 20 years. Despite their known benefits, GM crops also pose many concerns not only to human and animal health but also to the environment. Malaysia, in general, allows the use of GM technology applications but it has to come with precautionary and safety measures consistent with the international obligations and domestic legal frameworks. This paper provides an overview of GM crop technology from international and national context and explores the governance and issues surrounding this technology application in Malaysia. Basically, GM research activities in Malaysia are still at an early stage of research and development and most of the GM crops approved for release are limited for food, feed and processing purposes. Even though Malaysia has not planted any GM crops commercially, actions toward such a direction seem promising. Several issues concerning GM crops as discussed in this paper will become more complex as the number of GM crops and varieties commercialised globally increase and Malaysia starts to plant GM crops. © 2017 Society of Chemical Industry
Work‐related musculoskeletal symptoms among otolaryngologists by subspecialty: A national survey
Authors: Ho Thuy‐Van Tina , Hamill Chelsea S. , Sykes Kevin J. , Kraft Shannon M.
Published: September 2017

Objective

Given the high prevalence of work‐related musculoskeletal symptoms, increased appreciation for workplace ergonomics is critical. The purpose of this study is to assess work‐related musculoskeletal symptoms and injury among otolaryngologists across subspecialties, as well as to quantify the understanding and application of ergonomic principles in the operating room.

Study Design

Cross‐sectional study.

Methods

An online REDCap survey was distributed electronically to University of Kansas faculty, alumni, and residents; members of the American Academy of Facial Plastic and Reconstructive Surgery; and residency program coordinators for distribution to residents and faculty between August 2016 and March 2017. The survey assessed caseload, ergonomic practices, and associated musculoskeletal symptoms by type of procedure and impact of symptoms on surgeon practice.

Results

The survey was distributed to 3,006 individuals. We received 377 responses (12.5%), with 63.9% reporting symptoms. The majority of respondents began to experience symptoms in residency or fellowship. Neck and shoulder were the most affected body areas across all types of surgeries. One‐third of surgeons were formally taught or actively sought information on ergonomics principles. Among those who applied ergonomics in practice, 69.6% observed improvement in their symptoms.

Conclusion

Although musculoskeletal issues are prevalent among otolaryngologists, awareness of surgical ergonomics principles among otolaryngologists remains limited. Early instruction in ergonomic principles is important because work‐related musculoskeletal symptoms commonly present in residency. Most respondents reporting the application of ergonomic principles also acknowledge symptom improvement.

Level of Evidence

NA. Laryngoscope, 128:632–640, 2018
Laryngeal EMG: Preferential damage of the posterior cricoarytenoid muscle branches especially in iatrogenic recurrent laryngeal nerve lesions
Authors: Foerster Gerhard , Mueller Andreas H.
Published: September 2017

Objective

Laryngeal electromyography (LEMG) of the thyroarytenoid (TA) muscle alone may not be sufficient in all patients to characterize or prove a recurrent laryngeal nerve (RLN) lesion in cases of vocal fold immobility. LEMG of the posterior cricoarytenoid (PCA) muscle may provide additional information.

Study Design

Retrospective review.

Method

Between 2008 and 2016, 339 patients in our laryngeal paralysis clinic were examined by transcutaneous needle TA‐LEMG and, if tolerated, by PCA‐LEMG. LEMGs were rated and compared according to criteria of the European Laryngological Society. Etiology was categorized as iatrogenic, noniatrogenic, or malignancy related.

Results

A total of 282 out of 339 patients had a partial or complete RLN or vagal nerve lesion: 178 iatrogenic, 74 noniatrogenic, and 30 because of nerve involvement by malignancies. Of paralytic vocal folds, 35.7% had normal or near‐normal TA innervation, whereas corresponding PCA traces (if present) were pathologic in 94.6%. Comparing pairs of TA and PCA‐LEMGs in paralysis of less than 4 months duration showed a predominance of PCA branch injuries in iatrogenic lesions (71.7 %), while in noniatrogenic lesions this was less pronounced (44.4%). In the few malignancy cases, there was an almost even distribution. Synkinetic reinnervation was earlier in iatrogenic RLN lesions.

Conclusion

PCA‐LEMG was better in proving an RLN lesion than TA‐EMG alone. Our findings suggest etiology‐dependent differences in the TA/PCA lesion pattern. To confirm this, larger sample sizes are needed. A preferential damage to PCA innervation in iatrogenic lesions could be relevant for further improvements of intraoperative neuromonitoring.

Level of Evidence

4. Laryngoscope, 128:1152–1156, 2018
Chemosensory function before and after multimodal treatment in chronic rhinosinusitis patients
Authors: Walliczek‐Dworschak Ute , Pellegrino Robert , Taube Franziska , Mueller Christian A. , Stuck Boris Alexander , Dworschak Philipp , Güldner Christian , Steinbach Silke
Published: September 2017

Objectives/Hypothesis

Olfactory dysfunction is common among the general population, with chronic rhinosinusitis (CRS) as one of the leading causes. Patients affected by CRS often report changes in taste sensations; however, quantitative measurements have not been performed to date. Therefore, the present study aimed to investigate gustatory and olfactory function in CRS patients prior to and after multimodal treatment.

Study Design

Prospective cohort study.

Methods

Twenty‐one patients suffering from CRS with nasal polyps (14 male, seven female) with a mean age of 48 ± 15 years were included in the study. Chemosensory function was assessed prior to and approximately 190 days after multimodal treatment, which included endoscopic sinus surgery, oral antibiotics for 5 days, oral steroids for 12 days, and at least 6 weeks of topical nasal steroids. Olfactory function was tested with the Sniffin’ Sticks test battery, whereas gustatory function was measured with taste strips. A clinically relevant change in olfactory function was defined as a change of ≥5 points in the threshold, discrimination, and identification scores.

Results

Compared to normative data, patients baseline gustatory and olfactory function was impaired. After multimodal treatment, improvements were seen in olfactory function for eight patients (42%), remained stable in 10 patients (53%), and deteriorated in one patient (5%). Taste function remained unchanged following sinus surgery.

Conclusions

Patients suffering from CRS with polyps exhibit olfactory and taste dysfunctions. Multimodal treatment leads to an improvement in olfactory, but not gustatory functionality.

Level of Evidence

4. Laryngoscope, 128:E86–E90, 2018