bluuebunny/crossref_metadata_2025 huggingface dataset:
The robotic ENT microsurgery system: A novel robotic platform for microvascular surgery
Authors: Feng Allen L. , Razavi Christopher R. , Lakshminarayanan Pranav , Ashai Zaid , Olds Kevin , Balicki Marcin , Gooi Zhen , Day Andrew T. , Taylor Russell H. , Richmon Jeremy D.
Published: June 2017

Objective

Assess the feasibility of a novel robotic platform for use in microvascular surgery.

Study Design

Prospective feasibility study.

Setting

Robotics laboratory.

Methods

The Robotic ENT (Ear, Nose, and Throat) Microsurgery System (REMS) (Galen Robotics, Inc., Sunnyvale, CA) is a robotic arm that stabilizes a surgeon's instrument, allowing precise, tremor‐free movement. Six microvascular naïve medical students and one microvascular expert performed microvascular anastomosis of a chicken ischiatic artery, with and without the REMS. Trials were blindly graded by seven microvascular surgeons using a microvascular tremor scale (MTS) based on instrument tip movement as a function of vessel width. Time to completion (TTC) was measured, and an exit survey assessed participants' experience. The interrater reliability of the MTS was calculated.

Results

For microvascular‐naïve participants, the mean MTS score for REMS‐assisted trials was 0.72 (95% confidence interval [CI] 0.64–1.07) and 2.40 (95% CI 2.12–2.69) for freehand (P < 0.001). The mean TTC was 1,265 seconds for REMS‐assisted trials and 1,320 seconds for freehand (P > 0.05). For the microvascular expert, the mean REMS‐assisted MTS score was 0.71 (95% CI 0.15–1.27) and 0.86 (95% CI 0.35–1.37) for freehand (P > 0.05). TTC was 353 seconds for the REMS‐assisted trial and 299 seconds for freehand. All participants thought the REMS was more accurate and improved instrument handling and stability. The intraclass correlation coefficient for MTS ratings was 0.914 (95% CI 0.823–0.968) for consistency and 0.901 (95% CI 0.795–0.963) for absolute value.

Conclusion

The REMS is a feasible adjunct for microvascular surgery and a potential teaching tool capable of reducing tremor in novice users. Furthermore, the MTS is a feasible grading system for assessing microvascular tremor.

Level of Evidence

NA. Laryngoscope, 127:2495–2500, 2017
Simultaneous versus sequential bilateral cochlear implants in adults: Cost analysis in a US setting
Authors: Trinidade Aaron , Page Joshua C. , Kennett Sarah W. , Cox Matthew D. , Dornhoffer John L.
Published: June 2017

Objectives/Hypothesis

From a purely surgical efficiency point of view, simultaneous cochlear implantation (SimCI) is more cost‐effective than sequential cochlear implantation (SeqCI) when total direct costs are considered (implant and hospital costs). However, in a setting where only SeqCI is practiced and a proportion of initially unilaterally implanted patients do not progress to a second implant, this may not be the case, especially when audiological costs are factored in. We present a cost analysis of such a scenario as would occur in our institution.

Study Design

Retrospective review and cost analysis.

Methods

Between 2005 and 2015, 370 patients fulfilled the audiological criteria for bilateral implantation. Of those, 267 (72.1%) underwent unilateral cochlear implantation only, 101 (27.3%) progressed to SeqCI, and two underwent SimCI. The total hospital, surgical, and implant costs, and initial implant stimulation series audiological costs between August 2015 and August 2016 (29 adult patients) were used in this analysis.

Results

The total hospital, surgical, and implant costs for this period was $2,731,360.42. Based on previous local trends, if a projected eight (27.3%) of these patients decide to progress to SeqCI, this will cost an additional $750,811.04, resulting in an overall total of $3,482,171.46 for these 29 patients. Had all 29 undergone SimCI, the total projected cost would have been $3,332,991.75, representing a total potential saving of $149,179.67 (4.3%).

Conclusions

In institutions where only SeqCI is allowed in adults, overall patient management may cost marginally more than if SimCI were practiced. This will be of interest to CI programs and health insurance companies.

Level of Evidence

4. Laryngoscope, 127:2615–2618, 2017
Serial office‐based steroid injections for treatment of idiopathic subglottic stenosis
Authors: Hoffman Matthew R. , Coughlin Adam R. , Dailey Seth H.
Published: June 2017

Objectives/Hypothesis

Current treatment options for idiopathic subglottic stenosis include endoscopic interventions, resection, and tracheotomy. Recently, serial office‐based steroid injections were proposed as an alternative that may stabilize or induce regression of airway stenosis without the need for repeated operations. Procedure completion rate, pain, complications, effect on stenosis, time since the last operation, and limitations have not been described.

Study Design

Retrospective case series.

Methods

Retrospective series of 19 patients undergoing serial office‐based steroid injection for idiopathic subglottic stenosis. Outcome measures included completion rate, procedure‐related pain scores, complications, percentage of airway stenosis, and time since the last operative intervention.

Results

Procedure completion rate was 98.8%. Average pain score during the procedure was 2.3 ± 1.7 on a 10‐point scale. There were no immediate complications. One patient underwent awake tracheotomy 8 days after her second injection and was later decannulated. Average stenosis decreased from 35% ± 15% to 25% ± 15% (n = 16; P = .086) over the first of three injections and 40% ± 15% to 25% ± 10% to 20% ± 10% (n = 8; P = .002) for those patients completing two sets of three injections. Fourteen of 17 patients undergoing at least three injections have not returned to the operating room since the first injection.

Conclusions

Office‐based steroid injection represents a promising new treatment pathway for a disease that requires long‐term management, offering a purely pharmacologic approach to a disorder that has traditionally been approached from a mechanical perspective. It is safe, well tolerated, and effective. Furthermore, it may help patients and physicians avoid repeated trips to the operating room and the associated risks.

Level of Evidence

4. Laryngoscope, 127:2475–2481, 2017
Postoperative anticoagulation after free flap reconstruction for head and neck cancer: A systematic review
Authors: Barton Blair M. , Riley Charles A. , Fitzpatrick John C. , Hasney Christian P. , Moore Brian A. , McCoul Edward D.
Published: June 2017

Objective

Postoperative use of anticoagulation after free tissue transfer in head and neck ablative procedures is common practice, but a clear protocol has not been well established. The outcome measures including total flap failure, thrombosis, and hematoma formation for different anticoagulation regimens in free tissue transfer in the head and neck were reviewed.

Data Sources

PubMed, Ovid, and Cochrane databases were examined for patients who underwent free tissue transfer following head and neck ablative procedures.

Review Methods

Preferred Reporting Items for Systematic Reviews and Meta‐analyses guidelines were utilized to identify English‐language studies reporting anticoagulation regimens following free tissue transfer in head and neck ablative procedures. Outcomes included total flap failure, thrombosis, and hematoma formation. Two independent reviewers assessed the quality of the articles by using the Methodological Index for Non‐Randomized Studies.

Results

A total of 368 articles were identified. An additional 36 articles were identified through screening of reference lists. Twenty‐one of these studies met final inclusion criteria for qualitative analysis. Outcome data on total flap failure, thrombosis, and hematoma formation were extracted and analyzed for comparison against all anticoagulation regimens. Total flap failure, thrombosis, and hematoma formation rates were 4.4%, 4.5%, and 2.2%, respectively. Individual study rates ranged from 0.0% to 10.7%, 0.0% to 10.4%, and 0.6% to 7.2%, respectively.

Conclusions

There is not adequate evidence to develop a standardized anticoagulation protocol for head and neck free flap procedures. Comparable flap complications were reported between all the employed anticoagulation methods studied, though significant variability in study design among articles existed. Prospective, randomized studies are warranted to determine the optimal postoperative anticoagulation regimen following free tissue transfer of the head and neck. Laryngoscope, 128:412–421, 2018
On restricted simple modules of contact Lie superalgebras of odd type
Authors: Liu Wende , Wang Shujuan , Yuan Jixia
Published: June 2017

For contact Lie superalgebras of odd type over an algebraically closed field of characteristic , the composition factors of Kac modules and the character formulas for all the restricted simple modules are explicitly determined. And the dimensions of simple modules in the restricted supermodule category are precisely calculated, thereby dimensions of all the restricted simple modules are given.
Compressed perovskite aqueous mixtures near their phase transitions show very high permittivities: New prospects for high‐field MRI dielectric shimming
Authors: Neves Ana L. , Leroi Lisa , Raolison Zo , Cochinaire Nicolas , Letertre Thibaut , Abdeddaïm Redha , Enoch Stefan , Wenger Jerome , Berthelot Johann , Adenot‐Engelvin Anne‐Lise , Malléjac Nicolas , Mauconduit Franck , Vignaud Alexandre , Sabouroux Pierre
Published: June 2017

Purpose

Perovskites are greatly used nowadays in many technological applications because of their high permittivity, more specifically in the form of aqueous solutions, for MRI dielectric shimming. In this study, full dielectric characterizations of highly concentrated CaTiO3/BaTiO3 water mixtures were carried out and new permittivity maxima was reached.

Methods

Permittivity measurements were done on aqueous solutions from 0%v/v to dry powder. The permittivity dependence with pressure was investigated. Scanning electron microscopy images were performed on a few representative solutions. BaTiO3 pressed pads of different thicknesses, permittivities, and distances to the head were compared in a 7T MRI scanner.

Results

Perovskite aqueous mixtures undergo a pressure‐dependent phase transition in terms of permittivity, with increasing water content. A new relative permittivity maximum of 475 was achieved. Microscopic images revealed structural differences between phases. A
improvement in the temporal lobe was obtained with thin, high permittivity BaTiO3 head.

Conclusions

This new preparation method allows improved pad geometry and placement, as a result of the high relative permittivity values achieved. This method has great significance for medical applications of MRI dielectric shimming, being easy to replicate and implement on a large scale. Magn Reson Med 79:1753–1765, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
A cross‐sectional study of the catheter management of neurogenic bladder after traumatic spinal cord injury
Authors: Lane Giulia I. , Driscoll Amy , Tawfik Kyrollos , Chrouser Kristin
Published: June 2017

Aims

This cross‐sectional study describes the catheter management of neurogenic bladder (NGB) in patients with traumatic spinal cord injury (tSCI) with emphasis on the motivations behind transitions between intermittent (IC) and indwelling catheters.

Methods

Patients at the Minneapolis VA with history of tSCI who utilized either intermittent catheterization (IC), urethral (UC) or suprapubic (SP) catheters, participated in a voluntary, anonymous survey regarding their bladder management strategies.

Results

A total of 100 patients participated, 94% were male and 90% Caucasian with median age of 61 years. Patients with current UC or SP were older than those utilizing IC (P = 0.002). The median age at injury and years since SCI were 32 years and 20.5 years, respectively. The median time with current modality was 11 years. A total of 27% of all patients reported at least one transition between catheter type. A total of 14 of 54 patients using IC had prior use of UC or SP, while 12/25 patients using SP and 10/21 patients using UC had prior use of IC. The most common reasons to stop IC included inconvenience, physician recommendation, and dislike of IC. A total of 53% of patients currently using UC or SP reported never using IC. Patients currently using SP were more content with their current catheterization method than those using UC or IC (P = 0.046).

Conclusions

Among patients using catheters for NGB, intermittent catheterization was the most common modality utilized and the transition between intermittent and indwelling catheter was most often influenced by patient preferences and clinician recommendations.
Numerical solution to a linear equation with tensor product structure
Authors: Fan Hung‐Yuan , Zhang Liping , Chu Eric King‐wah , Wei Yimin
Published: June 2017

We consider the numerical solution of a c‐stable linear equation in the tensor product space
, arising from a discretized elliptic partial differential equation in
. Utilizing the stability, we produce an equivalent d‐stable generalized Stein‐like equation, which can be solved iteratively. For large‐scale problems defined by sparse and structured matrices, the methods can be modified for further efficiency, producing algorithms of
computational complexity, under appropriate assumptions (with ns being the flop count for solving a linear system associated with
). Illustrative numerical examples will be presented.
Potent Prearranged Positive Allosteric Modulators of the Glucagon‐like Peptide‐1 Receptor
Authors: Jones Ben J. , Scopelliti Rosario , Tomas Alejandra , Bloom Stephen R. , Hodson David J. , Broichhagen Johannes
Published: June 2017

Drugs that allosterically modulate G protein‐coupled receptor (GPCR) activity display higher specificity and may improve disease treatment. However, the rational design of compounds that target the allosteric site is difficult, as conformations required for receptor activation are poorly understood. Guided by photopharmacology, a set of prearranged positive allosteric modulators (PAMs) with restricted degrees of freedom was designed and tested against the glucagon‐like peptide‐1 receptor (GLP‐1R), a GPCR involved in glucose homeostasis. Compounds incorporating a trans‐stilbene comprehensively outperformed those with a cis‐stilbene, as well as the benchmark BETP, as GLP‐1R PAMs. We also identified major effects of ligand conformation on GLP‐1R binding kinetics and signal bias. Thus, we describe a photopharmacology‐directed approach for rational drug design, and introduce a new class of stilbene‐containing PAM for the specific regulation of GPCR activity.
Decontamination and Remediation of the Sulfur Mustard Simulant CEES with “Off‐the‐Shelf” Reagents in Solution and Gel States: A Proof‐of‐Concept Study
Authors: Hiscock Jennifer R. , Bustone Gianluca P. , Clark Ewan R.
Published: June 2017

The decontamination and remediation of sulfur mustard chemical warfare agents remains an ongoing challenge. Herein, we report the use of “off‐the‐shelf” metal salts alongside commercially available peroxides to catalyze the degradation of the simulant 2‐chloroethyl ethyl sulfide (CEES) in solution and encapsulated within a supramolecular gel.
Synthesis of epoxy‐ended hyperbranched polyesters with reinforcing and toughening function for diglycidyl ether of bisphenol‐A
Authors: Wang Luping , Liang Yeyun , Yu Qian , Chen Sufang , Zhang Junheng , Miao Menghe , Zhang Daohong
Published: June 2017

Hyperbranched epoxy resins are excellent materials for toughening and reinforcing diglycidyl ether of bisphenol‐A (DGEBA), but the glass transition temperature usually decrease sharply. Here we report synthesis of novel epoxy‐ended hyperbranched polyesters (HEHP‐n, n = 1, 2, 3, and 4) with different molecular weights. Chemical structure of the HEHP‐n and intermediates were characterized by FT‐IR and 1H NMR. The HEHP‐n has shown remarkable effect for toughening and reinforcing DGEBA. The mechanical strength of the HEHP‐n/DGEBA composites first increased and then decreased as the molecular weight and content of HEHP‐n increased. When the composites contain 12 wt% HEHP‐3, the impact, flexural and tensile strengths of the cured HEHP‐n/DGEBA composites reached 48.0 kJ/m2, 41.2 MPa, and 74.8 MPa, respectively, which are 223.6%, 73.0%, and 46.1% higher than those of the cured DGEBA. The glass transition temperature of the cured HEHP‐n/DGEBA also increased in comparison with that of the epoxy‐ended hyperbranched polyesters/DGEBA composites reported previously. POLYM. COMPOS., 39:E2046–E2055, 2018. © 2017 Society of Plastics Engineers
Silver‐loaded HDPE/clay nanocomposites with antibacterial property: A potential replacement for commodity polyethylene plastic
Authors: Roy Anasuya , Joshi Mangala , Butola Bhupendra Singh , Srivastava A.K.
Published: June 2017

A silver intercalated clay based HDPE nanocomposite with excellent antibacterial activity has been reported for the first time. Antibacterial silver‐clay (Ag‐MMT) synthesized in laboratory was incorporated into HDPE to prepare antibacterial HDPE/Ag‐MMT nanocomposites. Silver has been chosen as it is a powerful antimicrobial agent with additional properties such as unique optical, electrical, and thermal characteristics. The nanocomposites were fabricated through melt mixing route in a twin‐screw extruder with varying Ag‐MMT concentrations. Transmission electron microscopy, scanning electron microscopy, differential scanning calorimetry, and X‐ray diffraction studies confirmed superior dispersion of clay platelets in HDPE. Dynamic oscillatory properties and mechanical characteristics of the nanocomposites were determined to observe the effect of Ag‐MMT on HDPE. Antimicrobial testing of these nanocomposites against Gram‐negative bacteriaEscherichia coliO157:H7 and Gram‐positive bacteriaStaphylococcus aureusshowed excellent bioactivity (>99%) at 5 wt% Ag‐MMT. These antibacterial plastic materials have potential to replace neat HDPE products in niche areas where antimicrobial property would be highly desirable. POLYM. COMPOS., 39:E366–E377, 2018. © 2017 Society of Plastics Engineers
Mechanical and viscoelastic study of functionalized MWCNTs/epoxy/Kevlar composites
Authors: Bassyouni Mohamed Ismail , Abdel‐Hamid Shereen M.‐S. , Abdel‐Aziz Mohamed Helmy , Zoromba Mohamed Shafick
Published: June 2017

Nanomaterials‐strengthened diglycidyl ether of bisphenol A (DGEBA) epoxy resin and aramid fiber composites were investigated for 0.16 wt% and 0.32 wt% of industrial and COOH‐functionalized multiwalled carbon nanotubes (MWCNTs). Epoxy/Kevlar fiber/MWCNT hybrid composites were prepared using a vacuum resin‐infusion molding method (VRIM) based on 0.68 aramid fiber mass fractions. The effects of MWCNTs on the viscoelastic, mechanical, and thermal properties of composites were investigated. The chemical structure of composites was studied using Fourier‐transform infrared spectroscopy. Samples with COOH‐functionalized nanotubes showed a strong impact on thermogravimetric analysis, in contrast to composites having the equivalent amount of industrial grade MWCNTs. The outcomes show that addition of MWCNTs to epoxy has a substantial influence on viscoelastic properties. The viscoelastic and thermal analyses show that storage modulus escalates with the addition of functionalized MWCNTs. Micrographs of MWCNTs‐enriched epoxy and Kevlar/epoxy samples revealed the uniform distribution of COOH‐functionalized MWCNTs in epoxy (as compared to industrial grade MWCNTs), resulting in increased interfacial strength between fiber/matrix. POLYM. COMPOS., 39:E2064–E2073, 2018. © 2017 Society of Plastics Engineers
Synthesis of methylene butyrolactone polymers from itaconic acid
Authors: Trotta Jacob T. , Jin Mengyuan , Stawiasz Katherine J. , Michaudel Quentin , Chen Wei‐Liang , Fors Brett P.
Published: June 2017

Herein, we report the transformation of β‐monomethyl itaconate, an inexpensive and biorenewable alternative to petroleum feedstocks, to the high‐value monomer α‐methylene‐γ,γ‐dimethyl‐γ‐butyrolactone (Me2MBL) through a selective addition strategy. This strategy is also applied to the synthesis of α‐methylene‐γ‐butyrolactone (MBL, tulipalin A), a monomer that can be polymerized to give materials with desirable properties (high decomposition temperature, glass transition temperature, and refractive index). Subsequent polymerization of both Me2MBL and MBL through reversible addition‐fragmentation chain‐transfer polymerization generates well‐defined poly(Me2MBL) and poly(MBL) (PMBL). Physical characterization of poly(Me2MBL) shows good physical properties comparable with known PMBL materials. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 2730–2737
When convergent syntheses of graft block copolymers diverge: The treachery of chemical images
Authors: Maher Michael J. , Schibur Haley J. , Bates Frank S.
Published: June 2017

A synthetic strategy to produce graft block copolymers (BCPs) with controlled grafting densities using both grafting‐through and grafting‐from methods is reported. For grafting‐through, poly(4‐methylcaprolactone‐block‐d,l‐lactide) macromonomers were synthesized with a polymerizable maleimide end group. These macromonomers were copolymerized using reversible addition‐fragmentation chain‐transfer (RAFT) polymerization with styrene and various amounts of N‐ethylmaleimide to control grafting density. A kinetic study showed that the macromonomers (>10 kDa) polymerized at the same rate as N‐ethylmaleimide under RAFT conditions, suggesting that uniform grafting density could be achieved. However, incorporating more than 5–10 grafts per chain was found to be challenging and potentially limited by kinetics. A higher number of grafts per chain with controlled densities was achieved using a grafting‐from technique. Macroinitiators of styrene, N‐ethylmaleimide, and N‐(2‐hydroxyethyl)maleimide were copolymerized with a fixed density of grafting sites. Subsequently, BCPs were grown off of the macroinitiator using ring‐opening transesterification polymerization (ROTEP). © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 3097–3104
Multi‐functional poly(vinylidene fluoride) graft copolymers
Authors: Kuila Atanu , Chatterjee Dhruba P. , Maity Nabasmita , Nandi Arun K.
Published: June 2017

Poly(vinylidene fluoride) (PVDF) is known for its biocompatibility, piezo and pyro‐electricity, and membrane forming capability. In order to tune its properties, modification through grafting from approach by atom transfer radical polymerization (ATRP) is preferred. Hydrophilic polymers like poly(ethylene glycol) methacrylate, poly(methacrylic acid), poly(dimethylaminoethyl methacrylate) (PDMAEMA), and so forth have been anchored from PVDF backbone in order to make permeation of water molecules through the PVDF based membranes. The successful solution grafting of PDMAEMA chains from PVDF backbone by ATRP resulted appreciable graft conversion and hence its bulk properties showed a significant change. This water soluble graft copolymer shows incredible mechanical and adhesive properties. PVDF‐g‐poly(n‐butyl methacrylate) generates honey‐comb porous film using “breath figure” technique. Recently, they have used further improvement of grafting where model ATRP initiators are anchored using atom transfer radical coupling and used them as macroinitiators for grafting. This approach simplified the grafting reactions even more and enabled successful grafting of a large number of monomers under relatively less drastic conditions with appreciable conversion compared with the previous conditions. This technique has resulted interesting solution properties, ion and electron conducting PVDF, antifouling membrane, super glue and super tough materials, capable of generating metal nanoparticles tunable with pH and temperature. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 2569–2584
Phase separation dynamics of a poly(vinyl methyl ether)/polystyrene (PVME/PS) blend studied by ultrafast differential scanning calorimetry
Authors: Luo Shaochuan , Wei Lai , Jiang Jing , Sha Ye , Xue Gi , Wang Xiaoliang , Zhou Dongshan
Published: June 2017

In this work, ultrafast differential scanning calorimetry (UFDSC) is used to study the dynamics of phase separation. Taking poly(vinyl methyl ether)/polystyrene (PVME/PS) blend as the example, we firstly obtained the phase diagram that has lower critical solution temperature (LCST), together with the glass transition temperature (Tg) of the homogeneous blend with different composition. Then, the dynamics of the phase separation of the PVME/PS blend with a mass ratio of 7:3 was studied in the time range from milliseconds to hours, by the virtue of small time and spatial resolution that UFDSC offers. The time dependence of the glass transition temperature (Tg) of PVME‐rich phase, shows a distinct change when the annealing temperature (Ta) changes from below to above 385 K. This corresponds to the transition from the nucleation and growth (NG) mechanism to the spinodal decomposition (SD) mechanism, as was verified by morphological and rheometric investigations. For the SD mechanism, the temperature‐dependent composition evolution in PVME‐rich domain was found to follow the Williams–Landel–Ferry (WLF) laws. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 1357–1364
Colloidal Flower‐Shaped Iron Oxide Nanoparticles: Synthesis Strategies and Coatings
Authors: Gavilán Helena , Kowalski Anja , Heinke David , Sugunan Abhilash , Sommertune Jens , Varón Miriam , Bogart Lara K. , Posth Oliver , Zeng Lunjie , González‐Alonso David , Balceris Christoph , Fock Jeppe , Wetterskog Erik , Frandsen Cathrine , Gehrke Nicole , Grüttner Cordula , Fornara Andrea , Ludwig Frank , Veintemillas‐Verdaguer Sabino , Johansson Christer , Morales M. Puerto
Published: June 2017

The assembly of magnetic cores into regular structures may notably influence the properties displayed by a magnetic colloid. Here, key synthesis parameters driving the self‐assembly process capable of organizing colloidal magnetic cores into highly regular and reproducible multi‐core nanoparticles are determined. In addition, a self‐consistent picture that explains the collective magnetic properties exhibited by these complex assemblies is achieved through structural, colloidal, and magnetic means. For this purpose, different strategies to obtain flower‐shaped iron oxide assemblies in the size range 25–100 nm are examined. The routes are based on the partial oxidation of Fe(OH)2, polyol‐mediated synthesis or the reduction of iron acetylacetonate. The nanoparticles are functionalized either with dextran, citric acid, or alternatively embedded in polystyrene and their long‐term stability is assessed. The core size is measured, calculated, and modeled using both structural and magnetic means, while the Debye model and multi‐core extended model are used to study interparticle interactions. This is the first step toward standardized protocols of synthesis and characterization of flower‐shaped nanoparticles.
Structural Insight into Stabilization of Pickering Emulsions with Fe3O4@SiO2 Nanoparticles for Enzyme Catalysis in Organic Media
Authors: Qu Yanning , Huang Renliang , Qi Wei , Qu Qi , Su Rongxin , He Zhimin
Published: June 2017

Encapsulation of enzymes with enhanced activity and recyclability in water‐in‐oil Pickering emulsions is a simple and efficient method for their immobilization; however, the effect produced by the structure of colloidal particles on the stabilization of the Pickering emulsion for enzyme catalysis has not been investigated in detail. In this study, four types of hydrophobic Fe3O4@SiO2 nanoparticles (NPs) with similar chemical compositions, particle diameters, but different surface characteristics have been prepared and utilized for enzyme encapsulation in various water‐in‐oil magnetic Pickering emulsions, after which the relationship between NPs structure, size of emulsions droplets, and enzyme activity is examined. The obtained results indicate that (i) the more hydrophobic Fe3O4@SiO2 NPs cause the higher enzyme activity; (ii) the higher hydrophobicity of oil phase also increases the enzyme activity, especially for Fe3O4@w‐SiO2 NPs which form in the solvent of water. The results are mainly attributed to the higher specific surface area of emulsion droplets and interfacial mass transfer of substrates through the interfaces of droplets. The reported data provide new insights into the mechanism of stabilization of Pickering emulsions for enhancing enzyme activity and demonstrate efficient theoretical references for enzyme immobilization and synthesis of stable and active biocatalysts with high recyclability.
Noncompetitive inhibition of human CYP2C9 in vitro by a commercial Rhodiola rosea product
Authors: Thu Ole Kristian Forstrønen , Spigset Olav , Hellum Bent
Published: June 2017

A commercial Rhodiola rosea (R. rosea) product has previously demonstrated CYP2C9 inhibition in humans. The purpose of this study was to provide in vitro inhibitory data for this particular interaction and to classify the mechanism of the interaction. Another aim was to examine the in vitro influence of ethanol on the CYP2C9 activity. Human CYP2C9 (wild type) isolated from a baculovirus‐infected cell system was incubated with 0.8 μmol/L losartan for 20 min. Sulfaphenazole was used as a positive control. The commercial R. rosea product “Arctic Root” was used as test inhibitor. Formation of the CYP2C9‐produced losartan metabolite EXP‐3174 was determined by validated LC‐MS/MS methodology. Possible mechanism‐based (irreversible) inhibition was evaluated using time‐ and NADPH‐dependent inhibition assays. Kinetic constants (Km, Vmax, and Ki) were calculated from a Lineweaver‐Burk plot. Mode of inhibition was determined. CYP2C9 was inhibited by “Arctic Root” with an IC50 (extract concentration yielding 50% reduction in enzyme activity) of 19.2 ± 2.7 μg/mL. Inhibitor concentrations of 20 μg/mL and 40 μg/mL yielded Ki values of 16.37 μg/mL and 5.59 μg/mL, respectively. The Lineweaver‐Burk plot showed noncompetitive inhibition mode. No time‐ or NADPH‐dependent inhibition was observed. The presence of ethanol inhibited CYP2C9 activity in a concentration‐dependent manner. In conclusion, the commercial R. rosea product “Arctic Root” demonstrated noncompetitive inhibition of CYP2C9 in vitro. Further work identifying the constituents responsible for this inhibition is needed.
A serious nightmare: psychiatric and neurologic adverse reactions to mefloquine are serious adverse reactions
Authors: Nevin Remington L.
Published: June 2017

Mefloquine (originally marketed as Lariam) is a neurotoxic quinoline derivative antimalarial drug that is known to cause serious and potentially lasting neuropsychiatric adverse reactions. Since 2013, drug regulators in several jurisdictions, including the United States, the United Kingdom, Ireland, and Canada, have required their mefloquine labels be updated to warn that when used for malaria prophylaxis the drug should be discontinued at the onset of neurologic or psychiatric symptoms. These recent changes to the international labeling serve to imply that psychiatric and neurologic reactions to mefloquine prophylaxis may be an early warning of an impending more serious reaction that may further jeopardize the patient with continued use of the drug. To prevent these more serious effects, these drug labels now warn that mefloquine should be discontinued and that patients seek immediate medical intervention to obtain an alternative antimalarial drug when psychiatric or neurologic symptoms occur. When used correctly for malaria prophylaxis as the updated labeling now directs, it is reasonable to expect that mefloquine will be discontinued, and an alternative drug substituted, in each patient who develops psychiatric or neurologic symptoms. This opinion discusses the implications of this updated labeling for the reporting of adverse reactions and for the continued use of the drug in malaria prophylaxis.
Pollen contamination in seed mixture increases the dominance of resistance to Bt maize in Spodoptera frugiperda (Lepidoptera: Noctuidae)
Authors: Yang Fei , Kerns David L , Brown Sebe , Head Graham P , Huang Fangneng
Published: June 2017

BACKGROUND

Seed mixture, also called ‘RIB’, has been used to provide refuge populations for delaying insect resistance. Pollen contamination in RIB could result in refuge kernels of non‐Bt maize expressing variable Bt proteins. Data are lacking regarding the impact of pollen contamination on evolution of resistance for ear‐feeding insects. Here, we used Spodoptera frugiperda and Cry1F‐maize as a model to examine if pollen contamination in RIB increases the dominance of insect resistance.

RESULTS

Pollen contamination caused >66% refuge kernels in 5:95% (non‐Bt:Bt) and 20:80% RIBs to express Cry1F protein. Survival at adult stage on pure non‐Bt ears was similar (54.4–63.3%) among Cry1F‐susceptible (SS), Cry1F‐resistant (RR) and Cry1F‐heterozygous (RS) S. frugiperda. On Bt ears, survival was similar between SS and RS (0.0–1.7%), but it was significantly less than that of RR (59.2%). On the two RIB refuge ears, survival at adult stage for RS (42.3% in 5:95% RIB; 50.0% in 20:80% RIB) was significantly higher than for SS (8.7% in 5:95% RIB; 10.0% in 20:80% RIB).

CONCLUSION

The results suggest that pollen contamination in RIB could increase the dominance of resistance for ear‐feeding insects by significantly reducing susceptible refuge populations and supporting higher survival of heterozygotes relative to homozygous susceptible insects. © 2017 Society of Chemical Industry
A quantitative assay for Amaranthus palmeri identification
Authors: Murphy Brent P , Plewa Diane E , Phillippi Elizabeth , Bissonnette Suzanne M , Tranel Patrick J
Published: June 2017

BACKGROUND

Amaranthus palmeri recently has been brought into the Midwestern USA as a contaminant in Conservation Reserve Program seeding mixes. Rapid species screening is required to mitigate the risk of continued species movement.

RESULTS

Markers were developed for A. palmeri‐specific nucleotide polymorphisms in the internal transcribed spacer of the ribosomal coding region. A quantitative polymerase chain reaction (qPCR) assay successfully identified A. palmeri from single‐plant samples, simulated mixed‐plant samples and seed mixtures.

CONCLUSION

A qPCR assay for distinguishing A. palmeri from 12 other Amaranthus spp. was developed and validated. The assay can consistently detect a single A. palmeri seed when present in a pool of 100 total Amaranthus spp. seeds. © 2017 Society of Chemical Industry
Protein Corona: Impact of Lymph Versus Blood in a Complex In Vitro Environment
Authors: Bonvin Debora , Aschauer Ulrich , Alexander Duncan T. L. , Chiappe Diego , Moniatte Marc , Hofmann Heinrich , Mionić Ebersold Marijana
Published: June 2017

In biological environments, the surface of nanoparticles (NPs) are modified by protein corona (PC) that determines their biological behavior. Unfortunately, in vitro tests still give different PC than in vivo tests causing in vitro–in vivo discrepancy; hence, in vitro studies are not indicative for the NPs' behavior in vivo. Here is demonstrated that PC in vitro is strongly influenced by the type of extracellular fluid (ECF), blood or lymph, by their high and low flow conditions and transitions between ECFs, and a combination of these parameters. As a result, this in vitro study approaches fluidic and dynamic variations to which NPs are exposed in vivo: different ECF that NPs encounter first in different injection routes, different transitions in‐between ECFs during circulation, and simultaneous change in the exposed flow in these transitions. The most‐abundant proteins in PCs are found to be not the most abundant in ECFs, but those having high affinity for binding to the surface of NPs. Moreover, some proteins are differently abundant in PCs at different flows, which indicate force‐promoted binding, catch bonds. These results suggest that future in vitro studies should consider more complex incubation conditions to improve the in vitro–in vivo consistency necessary for translational research.
RNA Biomarkers: Diagnostic and Prognostic Potentials and Recent Developments of Electrochemical Biosensors
Authors: Islam Md Nazmul , Masud Mostafa Kamal , Haque Md Hakimul , Hossain Md Shahriar Al , Yamauchi Yusuke , Nguyen Nam‐Trung , Shiddiky Muhammad J. A.
Published: June 2017

Ribonucleic acids (RNAs) are considered as effective and minimally invasive biomarkers for disease diagnosis and prognosis due to their critical role in the regulation of different cellular processes. Over the past several years, the rapid progress in RNA biomarker research has resulted in the development of a large number of high‐performance RNA‐detection methods. Most of these methods are based on molecular‐biology techniques such as quantitative reverse transcription polymerase chain reaction (RT‐qPCR), microarrays, and RNA sequencing. In recent years, considerable attention has also been dedicated to developing RNA biosensors, exploiting micro‐ and nanofabrication technologies, and various readout strategies, including electrochemical and optical transducers. Here, the recent developments of RNA biosensors are concisely reviewed with a special emphasis on electrochemical‐detection approaches. The following points are also highlighted: i) all the types of clinically relevant RNAs (mRNAs, miRNAs, lncRNAs) and their diagnostic and prognostic potential in cancer are outlined, ii) major challenges associated with current techniques are identified, followed by a critical analysis of how these challenges have been addressed by different biosensing approaches, and iii) the current requirements that still need to be met for effective screening of RNA biomarkers in both research and clinical settings.
Evolution of Desulfurization and Characterization of Inclusions in Dual Alloy Ingot Processed by Electroslag Remelting
Authors: Liu Yu , Zhang Zhao , Li Guangqiang , Wang Qiang , Wang Li , Li Baokuan
Published: June 2017

Desulfurization and characterization of inclusions during ESR of dual alloy ingot were experimentally studied. The composition and inclusions in electrode and ESR ingot were analyzed by means of various analytical techniques. The results show that the size of inclusions in ingot is smaller and more uniform. The single larger (Mn,Cr)S inclusion (11.6 µm) is found in NiCrMoV electrode. But, no single (Mn,Cr)S inclusion is found in NiCrMoV and CrMoV zones in dual alloy ingot, whereas found in transition zone (TZ). The size of inclusions in TZ is larger than that in NiCrMoV and CrMoV zones due to the inclusions with a thicker (Mn,Cr)S layer and large (Mn,Cr)S inclusions in TZ. Thermodynamic calculations show that (Mn,Cr)S inclusions with high x(Mn)/x(Cr) can precipitate at the solidification front of TZ due to the enrichment of [Mn] and [S] in residual liquid steel. To eliminate (Mn,Cr)S inclusions, a deeper desulfurization is needed. The sulfur content decreases from 0.039 (mass pct) to 0.0171% in NiCrMoV zone and from 0.011 to 0.0017% in CrMoV zone. The gasifying desulfurization plays a dominate role, the ratio of gasifying desulfurization is 92.2%.
Mesenchymal Stem Cells Stabilize Axonal Transports for Autophagic Clearance of α-Synuclein in Parkinsonian Models
Authors: Oh Se Hee , Lee Seok Cheol , Kim Dong Yeol , Kim Ha Na , Shin Jin Young , Ye Byoung Seok , Lee Phil Hyu
Published: June 2017

Genome-wide association studies have identified two loci, SNCA and the microtubule (MT)-associated protein tau, as common risk factors for Parkinson’s disease (PD). Specifically, α-synuclein directly destabilizes MT via tau phosphorylation and induces axonal transport deficits that are the primary events leading to an abnormal accumulation of α-synuclein that causes nigral dopaminergic cell loss. In this study, we demonstrated that mesenchymal stem cells (MSCs) could modulate cytoskeletal networks and trafficking to exert neuroprotective properties in wild-type or A53T α-synuclein overexpressing cells and mice. Moreover, we found that eukaryotic elongation factor 1A-2, a soluble factor derived from MSCs, stabilized MT assembly by decreasing calcium/calmodulin-dependent tau phosphorylation and induced autophagolysosome fusion, which was accompanied by an increase in the axonal motor proteins and increased neuronal survival. Our data suggest that MSCs have beneficial effects on axonal transports via MT stability by controlling α-synuclein-induced tau phosphorylation, indicating that MSCs may exert a protective role in the early stages of axonal transport defects in α-synucleinopathies.
Leveraging Social Networking for Talent Management: An Exploratory Study of Indian Firms
Authors: Nayak Sunanda , Bhatnagar Jyotsna , Budhwar Pawan
Published: June 2017

Utilizing the social capital and social network theories, this research explores and highlights how social networking has been strategically utilized as an effective tool by organizations for employer branding and innovative talent acquisition strategies in India. Qualitative data from 78 semistructured interviews with human resources (HR) professionals of information technology (IT), information technology–enabled services (ITeS), and talent acquisition organizations confirm the growing utilization of social networking sites (SNSs) as part of the organizational HR strategy for employer branding and talent sourcing, acquisition and retention, and reinforcing stronger relationship with their employees. The study contributes to the fields of talent management and social networks and has several key implications for practitioners regarding the usefulness of SNSs to organizational branding, talent management, and retention. © 2017 Wiley Periodicals, Inc.
The divide–expand–consolidate coupled cluster scheme
Authors: Kjærgaard Thomas , Baudin Pablo , Bykov Dmytro , Kristensen Kasper , Jørgensen Poul
Published: June 2017

The Divide‐Expand‐Consolidate (DEC) scheme is a linear‐scaling and massively parallel framework for high accuracy coupled cluster (CC) calculations on large molecular systems. It is designed as a black‐box method, which ensures error control in the correlation energy and molecular properties. DEC is combined with a massively parallel implementation to fully utilize modern manycore architectures providing a fast time to solution. The implementation ensures performance portability and will straightforwardly benefit from new hardware developments. The DEC scheme has been applied to several levels of CC theory and extended the range of application of those methods. WIREs Comput Mol Sci 2017, 7:e1319. doi: 10.1002/wcms.1319

This article is categorized under:

Electronic Structure Theory > Ab Initio Electronic Structure Methods

Software > Quantum Chemistry
Theory and applications of surface micro‐kinetics in the rational design of catalysts using density functional theory calculations
Authors: Mao Yu , Wang Hai‐Feng , Hu P.
Published: June 2017

Rational design of catalysts has long been an important and challenging goal in heterogeneous catalysis. To achieve this target, density functional theory (DFT) calculations and micro‐kinetics are two of the cornerstones. The DFT calculations make it possible to obtain microscopic properties of catalytic systems by computational simulations, and the micro‐kinetic modeling of surface reactions provides a tool to link quantum‐chemical data with macroscopic behaviors of the systems. In this review, we focus on the basic concepts and latest theoretical progresses of strategies for the catalysts design, including Brønsted−Evans−Polanyi relation, the volcano curve, and the activity window. Among the progresses, the theory of chemical potential kinetics in heterogeneous catalysis and its implications on catalysts design, which was developed by our group, are described in detail with extensive derivations. Furthermore, the applications of this method on screening low‐cost counter electrodes for dye‐sensitized solar cells are presented with experimental evidences. WIREs Comput Mol Sci 2017, 7:e1321. doi: 10.1002/wcms.1321

This article is categorized under:

Structure and Mechanism > Reaction Mechanisms and Catalysis

Theoretical and Physical Chemistry > Reaction Dynamics and Kinetics
A New Type of Dispersant [Sodium Salt of Styrene–Methacrylic Acid Copolymer (SSMA)/Montmorillonite (MMT) Nanocomposite] for Pesticide Water Dispersible Granules
Authors: Liu Zequan , Cheng Shuangyuan , Zhang Qiang
Published: June 2017

A new type of dispersant [sodium salt of styrene–methacrylic acid copolymer (SSMA)/montmorillonite (MMT) nanocomposite] with different content of the MMT was synthesized through in situ solution free radical copolymerization. X‐ray diffraction measurements and electron microscopy observations prove that SSMA molecules can enter the interlayer space of MMT and form an intercalated structure. There are both fully intercalated and partly intercalated structures in the nanocomposites, which are related to the loading content of MMT. Transmission and scanning electron microscopy images indicate that the exfoliation degree of MMT in the nanocomposites decrease with increasing MMT content. Infrared spectroscopy (FTIR) analysis shows that there are hydrogen‐bonding interactions between carboxyl groups of SSMA and hydroxyl groups of MMT. Atrazine water dispersible granules were prepared by using SSMA/MMT nanocomposite as dispersant and their suspensibility in aqueous solution was determined to evaluate the dispersion properties of the nanocomposite. The results show that the addition of MMT can not only increase the steric effect of the SSMA to improve its dispersion properties, but also reduce the production cost of SSMA. The optimum loading content of MMT is 10 wt%.
Antioxidant Efficacy of a New Synergistic, Multicomponent Formulation for Fish Oil Omega‐3 Concentrates
Authors: Moen Vidar , Stoknes Iren , Breivik Harald
Published: June 2017

Today, tocopherols serve as the industrial standard antioxidant protection for fish oil omega‐3 concentrates. Synergistic interactions between tocopherols, ascorbyl palmitate and natural polyphenols extracted from plant sources have been demonstrated in model systems. The main goal for this work was to develop a mix of such antioxidants with improved efficacy in the context of preserving industrial marine oil concentrates. The antioxidant formulation comprises tocopherols, ascorbyl palmitate, rosemary extract and green tea catechins. Part of the scope was to develop a method for dissolving green tea catechins in oil. The key element of the method is to introduce green tea on a lipid insoluble carrier when dissolving the extract in the oil, and thereafter remove the carrier by filtration. The antioxidant mix was tested against tocopherol in omega‐3 concentrates of minimum 300 mg/g eicosapentaenoic acid (EPA) plus 200 mg/g docosahexaenoic acid (DHA) in the form of triacylglycerides and ethyl esters. The mix was superior compared to tocopherols in suppressing both primary‐ and secondary oxidation. Weight increase measurements of oil in contact with air correlated well with standard oxidation tests within individual samples and the method was considered simple and useful for monitoring oxidation in omega‐3 concentrates.