bluuebunny/crossref_metadata_2025 huggingface dataset:
Asymmetric Organocatalytic Conjugate Addition of Electron‐Rich Phenols and 1,3‐Dicarbonyls to Arylsulfonyl Indoles in an Oil‐Water Biphasic System
Authors: Han Jeng‐Liang , Liao Yu‐Ting , Chang Chia‐Hao
Published: July 2019

The asymmetric conjugate addition of electron‐rich phenols and 1,3‐dicarbonyls with arylsulfonyl indoles catalyzed by bifunctional organocatalysts has been established. The chiral 3,3‐disubstituted oxindoles derivatives were obtained in good to high yields (up to 99 % yield) with high enantioselectivies (up to 98 % ee). This study showed that the oil‐water biphasic system contributed to the high efficiency and stereoselectivity.
Electroanalytical Determination of Cd(II) and Pb(II) in Bivalve Mollusks using Electrochemically Reduced Graphene Oxide‐based Electrode
Authors: Pizarro Jaime , Segura Rodrigo , Tapia Diego , Bollo Soledad , Sierra‐Rosales Paulina
Published: July 2019

An electrochemical sensor for the simultaneous determination of Cd(II) and Pb(II) by square wave anodic stripping voltammetry (SWASV) in bivalve mollusks using a glassy carbon electrode modified with electrochemically reduced graphene oxide has been developed. The modified surface was characterized by cyclic voltammetry, high resolution scanning electron microscopy (HR‐SEM), and Raman spectroscopy. The optimum conditions were optimized and a linear range was observed from 15–105 μg L−1 with a limits of detection of 15 μg L−1 for Cd(II) and Pb(II). The methodology was validated and applied in different samples of commercial bivalve mollusks with satisfactory results. The high conductivity and greater surface area of the modifying agent improves the preconcentration capacity of the electrochemical sensor, allowing to develop a simple, rapid and sensitive analysis in the detection of lead and cadmium in marine resources.
Antidiabetic Drug Metformin Oxidation andin situInteraction with dsDNA Using a dsDNA‐electrochemical Biosensor
Authors: Machini W. B. S. , Fernandes I. P. G. , Oliveira‐Brett A. M.
Published: July 2019

The antidiabetic drug metformin (MET) is one of a group of emerging pharmaceutical drug contaminants in the wastewater treatment plants. The electrochemical behaviour of MET−Cu(II) complex by differential pulse and square wave voltammetry, in a wide pH range, at a glassy carbon electrode modified with a carbon black dihexadecylphosphate film (CB−DHP/GCE), was investigated. The MET−Cu(II) complex oxidation showed one pH‐dependent process, which leads to the formation of an oxidation product, being oxidized at a lower potential. The electroanalytical MET−Cu(II) complex detection limit, LOD=0.63 μM, and quantification limit, LOQ=2.09 μM, were obtained, and the MET−Cu(II) complex determination in wastewater samples collected from a senior residence effluent, using the CB−DHP/GCE, was achieved. Considering MET toxicity, the electrochemical evaluation of MET−dsDNA interaction, in incubated solutions and using dsDNA‐electrochemical biosensors, following the changes in the oxidation peaks of guanosine and adenosine residues electrochemical currents, was also investigated. The MET−dsDNA interaction mechanism, for shorter times, occurs by the binding of MET molecules in the minor grooves of the dsDNA, and for long times, the stabilization of the MET−dsDNA complex, causing a local distortion and/or unwinding of dsDNA morphology, is described. However, MET did not promote DNA oxidative damage.
Electrochemical Aberrant Methylation Detection Based on Ferrocenyl Naphthalene Diimide Carrying β‐Cyclodextrin, FNC
Authors: Sato Shinobu , Nishi Yukiko , Takenaka Shigeori
Published: July 2019

Electrochemical detection of the specific gene carrying aberrant methylated cytosine was achieved by ferrocenyl naphthalene diimide carrying β‐cyclodextrin (β‐CD), FNC, coupled with the probe‐DNA‐immobilized electrode. The five CpG sites in a 24‐base sequence were selected as the target DNA on the CDH4 gene, which is associated with colorectal cancer. When methylated and unmethylated samples hybridized with the DNA probe (HS‐M24) immobilized on the electrode, an increased current signal was observed in the electrolyte containing FNC and correlated with the amount of target DNA. Furthermore, an increase in current (115 %) was observed when the PCR product of 105 bp was hybridized on the HS‐M24‐immobilized electrode, whereas a background level of current increase was observed in the case of unmethylated product. Such large discrimination ability might be due to the inter‐ and/or intra‐complex formation of ferrocene with β‐CD of FNC on the surface of the electrode.
Transoral robotic retropharyngeal lymph node dissection in a recurrent head and neck carcinoma
Authors: Petruzzi Gerardo , Zocchi Jacopo , Moretto Silvia , Pichi Barbara , Cristalli Giovanni , Mercante Giuseppe , Spriano Giuseppe , De Virgilio Armando , Pellini Raul
Published: July 2019

Background

A step‐by‐step demonstration of the transoral robotic surgical approach (TORS) used in retropharyngeal node dissection (RND) in a recurrent head and neck carcinoma.

Methods

Clinical human study of TORS RND via en bloc resection using a daVinci Si system (Intuitive Surgical, Inc., Sunnyvale, California).

Results

A daVinci Si system provided sufficient access, reach, and visualization to perform TORS‐RND. Access and exposure were achieved with a Feyh‐Kastenbauer (FK) retractor (Gyrus Medical Inc., Tuttlingen, Germany). Two surgical instruments and one 3D camera arm can be deployed with minimal collision or restriction of arm movement.

Conclusions

Routine transcervical, transparotid, and transmandibular RNDs can provoke potentially serious surgical morbidities and complications. This study demonstrates the technical feasibility of TORS RND in a 68‐year‐old man.
Capitalizing on specialists' services in rural family health unit: Interventional study
Authors: Abdel‐Razik Madiha Said , El Shafei Arwa Mohamed Hosney , Abd Al Moety AlShaimaa Mohammed , Al Amir Reham Yosry , Hosney Mennatallah Said
Published: July 2019

For achieving universal health coverage in Egypt, Ministry of Health aims to improve the accessibility to quality specialized health care.

Objectives

The objectives of the study were to explore legal and regulatory environment for the policy of specialists' visits to unit and assess the impact of gynecology specialist's visits on utilization pattern of gynecological services and clients' satisfaction.

Methods

Settings

The study settings were Ministry of Health/Headquarters, Giza Health Directorate, El‐Badrashin Health District and Hospital, and Met‐Rahinah Unit.

Study design

The study includes qualitative research (in‐depth interviews with policymakers at all Ministry of Health levels and focus group discussions with service providers) and quantitative research (interventional operation research using separate sample pretest (n = 210) and posttest (n = 209) and family‐planning service statistics).

Results

Analysis of specialist outreach services indicated integration absence between preventive and curative sectors. Capitalizing on the policy of specialists' outreach visits to the unit could support clients' access quality services and reduce referral to get specialist services in hospitals. There is a 6‐month intervention of scheduled visits of a female gynecologist to a rural health unit. The intervention led to 12% increase in efficiency and utilization of services compared with the previous 6 months. Clients' satisfaction increased from 27% to 73% after the intervention (.001, OR = 7.5, CI = 4.9‐11.6).

Conclusion

Scheduled specialists' visits increase services' efficiency and clients' satisfaction.
Establishment of a mouse model of troglitazone‐induced liver injury and analysis of its hepatotoxic mechanism
Authors: Jia Ru , Oda Shingo , Tsuneyama Koichi , Urano Yuya , Yokoi Tsuyoshi
Published: July 2019

Drug‐induced liver injury is a major problem in drug development and clinical drug therapy. Troglitazone (TGZ), a thiazolidinedione antidiabetic drug for the treatment of type II diabetes mellitus, was found to induce rare idiosyncratic severe liver injury in patients, which led to its withdrawal in 2000. However, in normal experimental animals in vivo TGZ has never induced liver injury. To explore TGZ hepatotoxic mechanism, we established a novel mouse model of TGZ‐induced liver injury. Administration of BALB/c female mice with a single intraperitoneal TGZ dose (300 mg/kg) significantly elevated alanine aminotransferase and aspartate aminotransferase levels 6 hours after the treatment. The ratio of oxidative stress marker glutathione/disulfide glutathione was significantly decreased. The increased hepatic mRNA levels of inflammation‐ and oxidative stress‐related factors were observed in TGZ‐treated mice. Subsequently, hepatic transcriptome profiles of TGZ‐exposed liver were compared with those of non‐hepatotoxic rosiglitazone. The Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway was activated in TGZ‐induced liver injury. The activation of the JAK/STAT pathway promoted phosphorylation of STAT3 in TGZ‐treated mice. Consequently, upregulation of STAT3 activation increased mRNA levels of its downstream genes. In conclusion, a single intraperitoneal dose of TGZ exposure could induce liver injury in BALB/c female mice and, by a hepatic transcriptomic analysis, we found that the activation of JAK/STAT pathway might be related to TGZ‐induced hepatotoxicity.
Higher dietary protein intake preserves lean body mass, lowers liver lipid deposition, and maintains metabolic control in participants with long‐chain fatty acid oxidation disorders
Authors: Gillingham Melanie B. , Elizondo Gabriela , Behrend Annie , Matern Dietrich , Schoeller Dale A. , Harding Cary O. , Purnell Jonathan Q.
Published: July 2019

Medical nutrition therapy for long‐chain fatty acid oxidation disorders (LC‐FAODs) currently emphasizes fasting avoidance, restricted dietary long‐chain fatty acid intake, supplementation with medium chain triglycerides, and increased carbohydrate intake. We hypothesize that increasing dietary protein intake relative to carbohydrate intake would preserve metabolic control yet induce physical benefits including reduced hepatic lipogenesis. Therefore, we compared two dietary approaches with similar fat intake but different carbohydrate to protein ratios in participants diagnosed with LC‐FAODs. Thirteen participants were enrolled and randomized into either a high‐protein (PRO) or a high‐carbohydrate (CHO) diet for 4 months. Baseline and 4‐month assessments included body composition, ectopic lipid deposition, and resting energy expenditure. End of study assessments also included total energy expenditure, metabolic responses to oral feedings, and whole‐body fatty acid oxidation capacity. At the end of the dietary intervention, both groups had similar energy expenditure, fat and glucose oxidation rates, and glucolipid responses to mixed meal and oral glucose loads. Neither dietary group experienced worsening symptoms related to their LC‐FAOD. Compared to the CHO group, the PRO group exhibited increased blood levels of short‐chain acylcarnitines, reduced intrahepatic lipid content, and maintained lean body mass while the CHO group lost lean mass. In patients with LC‐FAODs, increasing protein intake maintained metabolic control, reduced liver fat without risk of metabolic decompensation, and helped preserve lean body mass. We propose that a modest increase in dietary protein along with fasting avoidance and fat restriction may improve body composition and energy expenditure in patients with LC‐FAODs.
Association of IL1RN VNTR polymorphism with chikungunya infection: A study from Western India
Authors: Tripathy Anuradha S. , Ganu Mohini A. , Sonam Lata , Alagarasu K. , Walimbe Atul M. , Thanapati Subrat , Gupta Pooja , Puranik Shaila
Published: July 2019

Chikungunya, caused by the chikungunya virus (CHIKV) mostly presents as acute and chronic articular inflammatory manifestations. Interleukin 1 receptor antagonist (IL‐1RN) is a potent endogenous competitive inhibitor of IL‐1α and 1β and has an anti‐inflammatory role. The present study evaluated the possible association of IL1RN variable number tandem‐repeat (VNTR) alleles and genotypes, and CHIKV stimulated IL‐1RN cytokine production with resistance and/or susceptibility to chikungunya infection and disease state in 224 patients with chikungunya (61 patients with acute chikungunya and 163 patients with chronic chikungunya) and 355 healthy controls. Polymerase chain reaction, CHIKV stimulated cytokine assay and luminex platform were used for assessing polymorphism and protein levels respectively. The study revealed a significant association of IL1RN*1/*1 genotype under recessive genetic model with the risk of developing chikungunya infection. Our findings also indicated that IL1RN *2 allele under dominant mode was associated with protection to chronic chikungunya. The results also revealed a higher production of IL‐1 RN protein in patients with chronic chikungunya. To conclude, the results suggest the association of ILRN VNTR polymorphism and IL‐RN protein levels with chronic chikungunya.
Work‐contingent self‐esteem: A boon or bane for worker well‐being?
Authors: Kuykendall Lauren , Craig Lydia , Tay Louis
Published: July 2019

Work‐contingent self‐esteem (WCSE; the degree to which workers' self‐esteem is based on workplace performance) has positive consequences for performance, yet less is known about its consequences for well‐being. In this paper, we contribute to the literature on WCSE by examining the mechanisms through which it impacts well‐being at work and outside of work. We challenge contingent self‐esteem (CSE) theory (Crocker & Park, 2004), which argues that CSE negatively impacts well‐being by fostering internally controlled (introjected) motivation and diminishing autonomous motivation, by suggesting that WCSE fosters autonomous and internally controlled motivation and thus has both beneficial and harmful effects on well‐being. We also expand CSE theory by suggesting that WCSE can negatively impact well‐being outcomes by causing work–nonwork conflict. Results from a time‐separated design in a sample of full‐time employees supported our arguments, revealing that WCSE impacted well‐being at work through both autonomous and internally controlled work motivations. WCSE also had negative effects on well‐being at and outside of work through work–nonwork conflict. The beneficial effects of WCSE outweighed its harmful effects on job satisfaction and neutralized its harmful effects for all other outcomes. We discuss theoretical implications for CSE theory, self‐determination theory, and work–nonwork issues and note important practical implications.
A novel method for the preconcentration and determination of ampicillin using electromembrane microextraction followed by high‐performance liquid chromatography
Authors: Aghaei Ali , Erfani Jazi Mehdi , E Mlsna Todd , Kamyabi Mohammad Ali
Published: July 2019

Electromembrane extraction was used with high‐performance liquid chromatography for preconcentration and determination of ampicillin residues in cow milk. Ampicillin is transferred from an aqueous solution through a thin layer containing octan‐1‐ol, silver nanoparticles, and reduced graphene oxide which serves as a supported liquid membrane. Inside the fiber impregnated with supported liquid membrane mixture was filled 10 µL of an acceptor phase. Experimental parameters were optimized for extraction efficiency of ampicillin. Under the optimized conditions, the proposed method provided acceptable linear range (2–100 µg/L), satisfactory repeatability (RSD% < 7.1), low limit of detection (0.6 µg/L), and a high enrichment factor (295) corresponding to extraction recovery of 37%. Consequently, the proposed method was successfully applied for the determination of ampicillin residues in different cow milks.
Acoustic emissions during tensile test of DC06 and HCT600X
Authors: Behrens B.A. , Hübner S. , Wölki K.
Published: July 2019

In this paper the acoustic emission behaviour during tensile tests of the materials DC06 and HCT600X is studied. Two steels with different characteristics (mild deep‐drawing steel DC06 and high‐strength steel HCT600X) are consciously chosen to show the influence of the material properties on the generated acoustic emissions. The acoustic emission behaviour and the corresponding signals differ clearly from each other. In addition, the effect of the strain rate as well as the rolling direction (0°, 90°) on the acoustic emission behaviour is investigated. Both parameters have a significant influence on the resulting acoustic emissions during tensile deformation. Furthermore, a new criterion based on the acoustic emission parameter FCOG (centroid frequency) for detection of damage beginning in dual‐phase steels is developed. The criterion supports the assumption that during tensile deformation of dual‐phase steels two failure mechanisms, ferrite/martensite interface decohesion and martensite phase fracture, exist.
Miniaturization of low cycle fatigue‐testing of single crystal superalloys at high temperature for uncoated and coated specimens
Authors: Meid C. , Waedt U. , Subramaniam A. , Wischek J. , Bartsch M. , Terberger P. , Vaßen R.
Published: July 2019

A newly developed miniature specimen and respective fixture for high temperature low cycle fatigue testing of nickel based single crystal superalloys is presented. Miniaturization allows the preparation of test specimens in all main crystallographic orientations of the cubic nickel crystal using laboratory sized material samples and enables excellent utilization of the costly material. The specimen geometry is optimized by means of parameter studies employing numerical calculations such that for the main crystallographic orientations the stress concentration at the fillet between gauge length and specimen head is minimized, and failure is likely to occur within the gauge length. The designed fixture allows easy specimen mounting and provides sufficient support for applying an extensometer for strain measurement. Protective metallic coatings against oxidation can be applied on the specimen by plasma spraying for studying the effect of coatings on the fatigue lifetime. The functionality of the specimen geometry and fixture design for low cycle fatigue testing is demonstrated for temperatures up to 950 °C.
Biophysically motivated efficient estimation of the spatially isotropic component from a single gradient‐recalled echo measurement
Authors: Papazoglou Sebastian , Streubel Tobias , Ashtarayeh Mohammad , Pine Kerrin J. , Edwards Luke J. , Brammerloh Malte , Kirilina Evgeniya , Morawski Markus , Jäger Carsten , Geyer Stefan , Callaghan Martina F. , Weiskopf Nikolaus , Mohammadi Siawoosh
Published: July 2019

Purpose

To propose and validate an efficient method, based on a biophysically motivated signal model, for removing the orientation‐dependent part of using a single gradient‐recalled echo (GRE) measurement.

Methods

The proposed method utilized a temporal second‐order approximation of the hollow‐cylinder‐fiber model, in which the parameter describing the linear signal decay corresponded to the orientation‐independent part of . The estimated parameters were compared to the classical, mono‐exponential decay model for in a sample of an ex vivo human optic chiasm (OC). The OC was measured at 16 distinct orientations relative to the external magnetic field using GRE at 7T. To show that the proposed signal model can remove the orientation dependence of , it was compared to the established phenomenological method for separating into orientation‐dependent and ‐independent parts.

Results

Using the phenomenological method on the classical signal model, the well‐known separation of into orientation‐dependent and ‐independent parts was verified. For the proposed model, no significant orientation dependence in the linear signal decay parameter was observed.

Conclusions

Since the proposed second‐order model features orientation‐dependent and ‐independent components at distinct temporal orders, it can be used to remove the orientation dependence of using only a single GRE measurement.
Simultaneous metabolic and functional imaging of the brain using SPICE
Authors: Guo Rong , Zhao Yibo , Li Yudu , Li Yao , Liang Zhi‐Pei
Published: July 2019

Purpose

To enable simultaneous high‐resolution mapping of brain function and metabolism.

Methods

An encoding scheme was designed for interleaved acquisition of functional MRI (fMRI) data in echo volume imaging trajectories and MR spectroscopic imaging (MRSI) data in echo‐planar spectroscopic imaging trajectories. The scheme eliminates water and lipid suppression and utilizes free induction decay signals to encode both functional and metabolic information with ultrashort TE, short TR, and sparse sampling of ‐space. A subspace‐based image reconstruction method was introduced for processing both the fMRI and MRSI data. The complementary information in the fMRI and MRSI data sets was also utilized to improve image reconstruction in the presence of intrascan head motion, field drift, and tissue susceptibility changes.

Results

In‐vivo experimental results were obtained from healthy human subjects in resting‐state fMRI/MRSI experiments. In these experiments, the proposed method was able to simultaneously acquire metabolic and functional information from the brain in high resolution. For scans of 6.5 minutes, we achieved 3.0 × 3.0 × 1.8 mm3 spatial resolution for fMRI, 1.9 × 2.5 × 3.0 mm3 nominal spatial resolution for MRSI, and 1.9 × 1.9 × 1.8 mm3 nominal spatial resolution for quantitative susceptibility maps.

Conclusion

This work demonstrates the feasibility of simultaneous high‐resolution mapping of brain function and metabolism with improved spatial resolution and synergistic image reconstruction.
Suprascapular neuropathy: A review of 87 cases
Authors: Memon Anza B. , Dymm Braydon , Ahmad Bashiruddin K. , Sripathi Naganand , Schultz Lonni , Chandok Arun
Published: July 2019

Introduction

Suprascapular neuropathy (SSN) is rare, with an estimated prevalence of 4.3% in patients with shoulder pain.

Methods

This retrospective chart review included patients with SSN seen during a 16‐year period. Demographics and clinical information were recorded. Descriptive statistics, including percentages, means, and standard deviations, were computed for the variables of interest for all patients.

Results

Of 87 patients included in this study, trauma (n = 27) was the most common cause of SSN, followed by neuralgic amyotrophy (n = 21). Fifty‐seven patients had isolated SSN. Others had SSN associated with axillary neuropathy (23 patients), brachial plexopathy (3 patients), and long thoracic, radial, or spinal accessory neuropathy (1 patient each).

Discussion

SSN is commonly associated with axillary neuropathy. Trauma remains the most common cause of SSN. Electrodiagnostic findings aid in the initial diagnosis and may indicate the need for close clinical follow‐up based on the severity of the axonal injury.
Nanofibrous poly(ethylene oxide)‐based structures incorporated with multi‐walled carbon nanotube and graphene oxide as all‐solid‐state electrolytes for lithium ion batteries
Authors: Banitaba Seyedeh Nooshin , Semnani Dariush , Heydari‐Soureshjani Elahe , Rezaei Behzad , Ensafi Ali Asghar
Published: July 2019

Nanofibrous solid polymer electrolytes were prepared using the electrospinning method. These nanofibres were constructed from poly(ethylene oxide), lithium perchlorate and ethylene carbonate, which were incorporated with multi‐walled carbon nanotube (MWCNT) and graphene oxide (GO). The morphological properties of the as‐prepared electrolytes and the interaction between the components of the composites were characterized using scanning electron microscopy and Fourier transform infrared spectroscopy, respectively. X‐ray spectra and differential scanning calorimetry indicated an increase in amorphous regions of the nanofibrous electrolytes on addition of the fillers. However, the crystalline regions were increased on incorporation of fillers into polymeric film electrolytes. The conductivity values of the nanofibrous electrolytes reached 0.048 and 0.057 mS cm−1 when 0.35 wt% MWCNT and 0.21 wt % GO were introduced into the nanofibrous structures, respectively. The capacity and cycling stability of the nanofibrous electrolytes were improved by incorporation of MWCNT filler. Furthermore, stress and elongation modulus were improved at low MWCNT and GO filler contents. Results revealed that the nanofibrous structures could be promising candidates as solvent‐free electrolytes applicable in lithium ion batteries. © 2019 Society of Chemical Industry
Ignition of Mechanically Activated Aluminum Powders Doped with Metal Oxides
Authors: Dossi Stefano , Maggi Filippo
Published: July 2019

Use of mechanical milling to increase micrometric powder reactivity is of interest due to several intrinsic advantages of this technique (e. g. versatility and safety). In this work, 30 μm propulsion‐grade aluminum has been activated with and without metal oxides. The powders so obtained were characterized in terms of particle size distribution, metal content, morphology, and ignition temperature. This last parameter represents a good indicator to rate the reaction properties of powders and the effects of activation parameters on the final product. All the ingredients containing metal oxides feature an enhanced reactivity as a consequence of both additives and modification of particle morphology.
Effect of Temperature on Shock Initiation of RDX‐Based Aluminized Explosives
Authors: Zhao Pin , Chen Lang , Yang Kun , Geng Deshen , Lu Jianying , Wu Junying
Published: July 2019

An increase in temperature of an explosive will lead shock sensitivity to change, which affects explosive safety. Therefore, a study of the effect of temperature on the shock initiation of explosives is of great significance. We carried out a series of tests on explosive‐driven flyer‐initiating heated RDX‐based aluminized explosives (61 wt % RDX, 30 wt % Al, 9 wt % binder) and the temperature and input shock pressure of the explosives were controlled accurately during the tests. The pressure histories at different depths inside the explosives were measured by using manganin pressure gauges, and the effect of temperature on detonation wave growth was analysed. The ignition and growth reaction model, some parameters of which rely on temperature, was used to simulate the shock‐initiation processes. The relationship between the model parameters and the temperature were obtained from the experimental results. The run distance to detonation as a function of the initial input pressure in a temperature range, the Pop plot, and the reaction degree of the explosives were determined. For the RDX‐based aluminized explosives, binder softening and the increasing sensitivity of RDX are the two main reasons that change the shock sensitivity. For 25 °C–110 °C, the shock sensitivity decreases with an increase in temperature, mainly because of binder softening. However, for 110 °C–170 °C, the shock sensitivity increases with an increase in temperature, which depends on the increasing sensitivity of the RDX.
Structural modeling of protein complexes: Current capabilities and challenges
Authors: Dapkūnas Justas , Olechnovič Kliment , Venclovas Česlovas
Published: July 2019

Proteins frequently interact with each other, and the knowledge of structures of the corresponding protein complexes is necessary to understand how they function. Computational methods are increasingly used to provide structural models of protein complexes. Not surprisingly, community‐wide Critical Assessment of protein Structure Prediction (CASP) experiments have recently started monitoring the progress in this research area. We participated in CASP13 with the aim to evaluate our current capabilities in modeling of protein complexes and to gain a better understanding of factors that exert the largest impact on these capabilities. To model protein complexes in CASP13, we applied template‐based modeling, free docking and hybrid techniques that enabled us to generate models of the topmost quality for 27 of 42 multimers. If templates for protein complexes could be identified, we modeled the structures with reasonable accuracy by straightforward homology modeling. If only partial templates were available, it was nevertheless possible to predict the interaction interfaces correctly or to generate acceptable models for protein complexes by combining template‐based modeling with docking. If no templates were available, we used rigid‐body docking with limited success. However, in some free docking models, despite the incorrect subunit orientation and missed interface contacts, the approximate location of protein binding sites was identified correctly. Apparently, our overall performance in docking was limited by the quality of monomer models and by the imperfection of scoring methods. The impact of human intervention on our results in modeling of protein complexes was significant indicating the need for improvements of automatic methods.
A free‐energy landscape for the glucagon‐like peptide 1 receptor GLP1R
Authors: Alhadeff Raphael , Warshel Arieh
Published: July 2019

G‐protein‐coupled receptors (GPCRs) are among the most important receptors in human physiology and pathology. They serve as master regulators of numerous key processes and are involved in as well as cause debilitating diseases. Consequently, GPCRs are among the most attractive targets for drug design and pharmaceutical interventions (>30% of drugs on the market). The glucagon‐like peptide 1 (GLP‐1) hormone receptor GLP1R is closely involved in insulin secretion by pancreatic β‐cells and constitutes a major druggable target for the development of anti‐diabetes and obesity agents. GLP1R structure was recently solved, with ligands, allosteric modulators and as part of a complex with its cognate G protein. However, the translation of this structural data into structure/function understanding remains limited. The current study functionally characterizes GLP1R with special emphasis on ligand and cellular partner binding interactions and presents a free‐energy landscape as well as a functional model of the activation cycle of GLP1R. Our results should facilitate a deeper understanding of the molecular mechanism underlying GLP1R activation, forming a basis for improved development of targeted therapeutics for diabetes and related disorders.
Polarization Engineering to Manipulate the Breakdown Voltage for GaN‐Based PIN Diodes
Authors: Hou Xu , Chen Xin , Jia Xingyu , Liu Yajin , Zhang Yonghui , Zhang Zi-Hui , Kuo Hao-Chung
Published: July 2019

This study proposes to increase the breakdown voltage for GaN‐based PIN diodes using the polarization effect, such that a thin AlGaN layer is inserted into the drift layer to modulate the electric field profiles, and by properly designing the device architecture, the electric field in the drift layer can be remarkably reduced by the polarization effect, and this enables the enhancement of the breakdown voltage. The study further investigates the parametric sensitivity of the breakdown voltage for the proposed GaN‐based PIN diodes to different device structures with various drift layer thicknesses. Moreover, it is found that the position of the inserted AlGaN thin layer is also important in affecting the breakdown voltage, such that the AlGaN insertion layer reduces the electric field with the maximum intensity in the drift layer.
Role of Impurities in Silicon Solidification and Electrical Properties Studied by Complementary In Situ and Ex Situ Methods
Authors: Ouaddah Hadjer , Périchaud Isabelle , Barakel Damien , Palais Olivier , Di Sabatino Marisa , Reinhart Guillaume , Regula Gabrielle , Mangelinck-Noël Nathalie
Published: July 2019

All silicon (Si) ingot fabrication processes share challenges to control grain structure, defect, and impurity contamination during the solidification step to improve the material properties. The final grain structure and inherent structural defects issued from the solidification step are responsible for the photovoltaic (PV) properties for a large part, all the more as they are often associated with impurity distribution. Impurities play a major role as they not only can modify the development of the grain structure formation but can also interact with structural defects creating the regions of deleterious minority carrier lifetime recombination. Samples containing different levels of impurities and solidified with different processes are selected and analyzed as‐grown or observed by X‐ray imaging during resolidification from as‐grown seeds. The growth features and relative crystallographic orientation of neighbor grains are characterized. Moreover, minority carrier lifetime measurements are performed and correlated with the growth features. The complementarity of the different techniques improves the understanding of phenomena at stake during the formation of grains and twins, the effect of impurities, and their impact on photovoltaic properties. The results show the significant influence of light and metallic impurities, such as copper, on the grain structure and on the electrical properties.
Saponins as chemosensitizing substances that improve effectiveness and selectivity of anticancer drug—Minireview of in vitro studies
Authors: Koczurkiewicz Paulina , Klaś Katarzyna , Grabowska Karolina , Piska Kamil , Rogowska Katarzyna , Wójcik‐Pszczoła Katarzyna , Podolak Irma , Galanty Agnieszka , Michalik Marta , Pękala Elżbieta
Published: July 2019

Triterpene saponins (saponosides) are found in higher plants and display a wide range of biological and pharmacological activities. The antitumor effects of saponins have been proved by their cytotoxic, cytostatic, proapoptotic, and anti‐invasive effects in many cellular models. Saponins hold great potential for being developed into chemopreventive and chemotherapeutic drugs. A promising way of reducing the adverse effects of chemotherapy without attenuating its efficiency is provided by the combined application of chemotherapeutic agents and saponosides in subtoxic concentrations. Until recently, saponosides were primarily used as adjuvants that enhance the effect of vaccines. In cancer therapy, saponins are applied in combination with immunotoxins because they increase the selectivity of given immunotoxins against cancer cells and therefore inure normal cells to the cytotoxic effects of immunotoxins. Significantly, certain saponins have been identified that drastically enhance the efficacy of many chemotherapeutic agents, including cisplatin, paclitaxel, doxorubicin, docetaxel, mitoxantrone, and cyclophosphamide. Moreover, saponins used in combination therapy enhance the sensitivity of chemoresistant tumor cells to clinically used chemotherapeutic agents. This review sheds light on the molecular mechanisms underlying cancer co–treatment with saponins and chemotherapy, with a particular focus on modulation of the cell signaling pathways associated with the promotion and progression of cancer cell proliferation, apoptosis, and metastasis.
Electric field amplification of plasmon‐molecule hybrids revealed by first‐principles time dependent density functional theory calculations
Authors: Muhammed Mufasila M. , John Joicy , Mokkath Junais H.
Published: July 2019

Using first‐principles quantum mechanical calculations, we investigate the electric field amplification in hybrid nanostructures composed of few‐atom Ni linear chains attached to an organic molecule. We found that the pristine Ni linear chains exhibit localized plasmons and produce nanoscale hotspot regions, acting as a plasmon‐like nanoantenna. We demonstrate that localized plasmons provide massive electric field amplification in the vicinity of the molecule. Besides, we also investigated the active modulation of the optical absorption spectra due to the inclusion of a positive and/or negative electric field in the Hamiltonian. We believe that the results presented in this work are important for the emerging field of cavity induced photo‐catalysis and will aid in the realization of new quantum nano‐optic devices.
Semiconductor Quantum Dots for Integrated Quantum Photonics
Authors: Hepp Stefan , Jetter Michael , Portalupi Simone Luca , Michler Peter
Published: July 2019

Quantum mechanics promises to have a strong impact on many aspects of research and technology, improving classical analogues via purely quantum effects. A large variety of tasks are currently under investigation, for example, the implementation of quantum computing, sensing, metrology, and communication. From a general perspective, in a similar way as classical computing benefited by the reduction of the device footprint, enabling the realization of highly complex chips, a range of quantum applications will sensibly improve thanks to the successful realization of on‐chip quantum photonics. Conversely to bulky table‐top experiments, it would be very advantageous to transfer all required functionalities on the same quantum photonic chip. The key elements for quantum photonic circuits are on‐demand nonclassical light sources, a versatile photonic logic, the ability to store quantum information, and highly efficient detectors, directly integrated on‐chip. Among several systems capable of the efficient generation of single‐ and indistinguishable photons, quantum dots are rapidly establishing as one of the most appealing candidates. This paper reviews the recent progress in the on‐chip integration of quantum‐dot‐based nonclassical light sources as well as in the development of the main building blocks, either integrated monolithically or hybridly on a compact and scalable platform.
Finite‐horizon fault estimation for time‐varying systems with multiple fading measurements under torus‐event–based protocols
Authors: Ju Yamei , Wei Guoliang , Ding Derui , Liu Shuai
Published: July 2019

In this paper, the issue of the finite‐horizon H∞ fault estimation is dealt with for a class of discrete time‐varying systems subject to randomly occurring faults and multiple fading measurements. The missing phenomena may occur in a random way from different sensors, which is represented by an individual stochastic variable meeting a certain probability distribution. Furthermore, in order to alleviate the communication burden, the torus‐event–based protocols are adopted to schedule the data transmissions only when some significant events occur. Our aim of the presented issue is to estimate the fault such that, with multiple fading measurements via the received information governed by torus‐event–based protocols, the H∞ index is satisfied over a given finite horizon. Sufficient conditions are obtained for the desired time‐varying estimator in terms of the technique of stochastic analysis and the methods of completing squares. The desired estimator gains are calculated by working out two backward recursive Riccati difference equations. Finally, a numerical simulation is given to verify the usefulness of our designed fault estimation approach.
Surface Modification of Polypropylene with Primary Amines by Acrylamide Radiation Grafting and Hofmann's Transposition Reaction
Authors: Rodríguez‐Alba Efraín , Huerta Lázaro , Ortega Alejandra , Burillo Guillermina
Published: July 2019

Polypropylene (PP) film surface is modified with primary amines by means of gamma radiation to graft acrylamide (AAm) using the pre‐irradiation oxidative method at a dose of 50 kGy, a monomer concentration of 13%, and a temperature of 60 °C for 6 h, followed by Hofmann rearrangement to reduce the primary amide groups of the grafted polymer (PP‐g‐AAm) to obtain vinylamine (VAm) groups (PP‐g‐VAm). The films are characterized using infrared spectroscopy before and after the reduction reaction; the hydrophilicity is studied using the contact angle; the thermal stability of the films are observed using TGA and DSC; and the surface morphology is determined using SEM. The presence of primary amines and the corresponding decrease in C=O and O=C‐NH2 groups due to reduction reaction, are confirmed using X‐ray photoelectron spectroscopy. In addition, the surface primary amines are quantified using a colorimetric method that calculated the amount as 1.9+0.1 nmol/mm2.
Inlaying Ultrathin Bimetallic MOF Nanosheets into 3D Ordered Macroporous Hydroxide for Superior Electrocatalytic Oxygen Evolution
Authors: Li Xiaofang , Ma Dong‐Dong , Cao Changsheng , Zou Ruqiang , Xu Qiang , Wu Xin‐Tao , Zhu Qi‐Long
Published: July 2019

Controllable synthesis of ultrathin metal–organic framework (MOF) nanosheets and rational design of their nano/microstructures in favor of electrochemical catalysis is critical for their renewable energy applications. Herein, an in situ growth method is proposed to prepare the ultrathin NiFe MOF nanosheets with a thickness of 1.5 nm, which are vertically inlaid into a 3D ordered macroporous structure of NiFe hydroxide. The well‐designed composite delivers an efficient electrocatalytic performance with a low overpotential of 270 mV at a current density of 10 mA cm−2 and stable electrolysis as long as 10 h toward the electrochemical oxygen evolution reaction, much superior to the state‐of‐the‐art RuO2 electrocatalyst. A comprehensive analysis demonstrates that the excellent performance originates from the desirable combination of the highly exposed active centers in the ultrathin bimetallic MOF nanosheets, effective electron conduction between MOF nanosheets and ordered macroporous hydroxide, and efficient mass transfer across the hierarchically porous hybridization. This study sheds light on the exploration of powerful protocols to gain diverse high‐performance MOF nanosheets and may open a perspective to achieve their efficient electrocatalytic performance.
Hydrophilic Fullerene Derivative Doping in Active Layer and Electron Transport Layer for Enhancing Oxygen Stability of Perovskite Solar Cells
Authors: Xu Guiying , Wang Shuhui , Bi Pengqing , Chen Haiyang , Zhang Moyao , Xue Rongming , Hao Xiaotao , Wang Zhaokui , Li Yaowen , Li Yongfang
Published: July 2019

Poor stability is one of the main limiting factors for the commercialization of perovskite solar cells (pero‐SCs). The degradation of perovskite films is usually triggered by the reaction of the perovskite active layer with the superoxide when exposed in ambient atmosphere, which is not prevented by simple encapsulation. Herein, an oxygen‐stabilizing effect is found by utilizing a hydrophilic [6,6]‐phenyl‐C61‐butyric acid‐(3,4,5‐tris(2‐(2‐(2‐methoxyethoxy)ethoxy)ethoxy)phenyl)methanol ester (PCBB‐OEG) as a dopant of the perovskite film and electron‐transporting layer (ETL). PCBB‐OEG accelerates photoelectron transport in perovskite films and enhances the electron‐extracting ability of ETL. This process is demonstrated to efficiently prevent the reaction between electrons and oxygen to form a superoxide. Hence, the presence of PCBB‐OEG in the perovskite film improves its stability against oxygen. The stability and efficiency of pero‐SCs are further improved by doping PCBB‐OEG in [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) ETL. As a result, the p‐i‐n pero‐SCs with PCBB‐OEG as an additive in both the perovskite active layer and ETL show the best power conversion efficiency of 20.49%. Importantly, the related device retains 98% of this initial efficiency after 60 days of storage in ambient atmosphere without encapsulation.
Mesoporous silica nanoparticles for tissue‐engineering applications
Authors: Chen Liang , Zhou Xiaojun , He Chuanglong
Published: July 2019

Mesoporous silica nanoparticles (MSNs) have been widely investigated as a nanocarrier for the delivery of various cargoes in nanomedicine. The application of MSNs in tissue engineering is a relatively newly emerged field that has gained much research interest. In this review, the recent advances in the tissue‐engineering application of MSNs are summarized. The controlled synthesis of MSNs is delineated first in terms of tuning the morphology, pore size of MSNs, and its surface chemistry, as well as biodegradability. Then, the different roles of MSNs in tissue engineering are successively introduced, which mainly comprise the delivery of bioactive factors, the inherent bioactivity of MSNs, stem cells labelling, and the impacts of incorporated MSNs on scaffolds. Furthermore, the recent progress in the applications of MSNs for tissue engineering, particularly bone tissue engineering, is summarized in detail. Finally, the challenges or potential trends for the further applications of MSNs in tissue engineering are also discussed.

This article is categorized under:

Implantable Materials and Surgical Technologies > Nanotechnology in Tissue Repair and Replacement

Implantable Materials and Surgical Technologies > Nanomaterials and Implants
Erratum to: Entanglement harvesting with moving mirrors
Authors: Cong Wan , Tjoa Erickson , Mann Robert B.
Published: July 2019

We provide a minor correction to the caption of figure 3, as well as a replacement for the left figure of figure 5.
Having a look at the Bayes Blind Spot
Authors: Rédei Miklós , Gyenis Zalán
Published: July 2019

The Bayes Blind Spot of a Bayesian Agent is, by definition, the set of probability measures on a Boolean$$\sigma $$σ-algebra that are absolutely continuous with respect to the background probability measure (prior) of a Bayesian Agent on the algebra and which the Bayesian Agent cannot learn by a single conditionalization no matter what (possibly uncertain) evidence he has about the elements in the Boolean$$\sigma $$σ-algebra. It is shown that if the Boolean algebra is finite, then the Bayes Blind Spot is a very large set: it has the same cardinality as the set of all probability measures (continuum); it has the same measure as the measure of the set of all probability measures (in the natural measure on the set of all probability measures); and is a “fat” (second Baire category) set in topological sense in the set of all probability measures taken with its natural topology. Features of the Bayes Blind Spot are determined from the perspective of repeated Bayesian learning when the Boolean algebra is finite. Open problems about the Bayes Blind Spot are formulated in probability spaces with infinite Boolean$$\sigma $$σ-algebras. The results are discussed from the perspective of Bayesianism.
Integrated process planning and scheduling in networked manufacturing systems for I4.0: a review and framework proposal
Authors: Varela Maria L. R. , Putnik Goran D. , Manupati Vijay K. , Rajyalakshmi Gadhamsetty , Trojanowska Justyna , Machado José
Published: July 2019

Integrated process planning and scheduling in networked manufacturing systems plays a crucial role nowadays and in the forthcoming context of Industry 4.0 to enable effective and efficient decisions, and to improve the business market, based on collaboration, along with computer-based distributed manufacturing and management functions. In this paper some insights regarding a literature review carried out about this main subjects analysed are presented and discussed. Moreover, a framework for integrated process planning and scheduling in networked manufacturing systems is proposed and briefly described, along with some main underlying issues, which are further discussed. Thus, the main purpose of this research consists on presenting a proposed methodology, based on the study conducted, to enable to further assist either academia or industry to develop new tools, techniques and approaches for integrated process planning in networked manufacturing environments. The findings and contributions of this research can help in the implementation and improvement in distributed manufacturing environments, to be linked with small and medium enterprises, to further expand their potentialities through well suited integrated process planning and scheduling decision making processes.