bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanisms of Neurodegeneration and Axonal Dysfunction in Progressive Multiple Sclerosis
Authors: Correale Jorge , Marrodan Mariano , Ysrraelit María Célica
Published: February 2019

Multiple Sclerosis (MS) is a major cause of neurological disability, which increases predominantly during disease progression as a result of cortical and grey matter structures involvement. The gradual accumulation of disability characteristic of the disease seems to also result from a different set of mechanisms, including in particular immune reactions confined to the Central Nervous System such as: (a) B-cell dysregulation, (b) CD8+ T cells causing demyelination or axonal/neuronal damage, and (c) microglial cell activation associated with neuritic transection found in cortical demyelinating lesions. Other potential drivers of neurodegeneration are generation of oxygen and nitrogen reactive species, and mitochondrial damage, inducing impaired energy production, and intra-axonal accumulation of Ca2+, which in turn activates a variety of catabolic enzymes ultimately leading to progressive proteolytic degradation of cytoskeleton proteins. Loss of axon energy provided by oligodendrocytes determines further axonal degeneration and neuronal loss. Clearly, these different mechanisms are not mutually exclusive and could act in combination. Given the multifactorial pathophysiology of progressive MS, many potential therapeutic targets could be investigated in the future. This remains however, an objective that has yet to be undertaken.
The Cognitive Profile of People with High-Functioning Autism Spectrum Disorders
Authors: Rabiee Atusa , Samadi Sayyed Ali , Vasaghi-Gharamaleki Behnoosh , Hosseini Soode , Seyedin Saba , Keyhani Mohammadreza , Mahmoodizadeh Ameneh , Ranjbar Kermani Fatemeh
Published: February 2019

Several studies have examined the cognitive profile of people with high-functioning autism spectrum disorders (ASD) (IQ > 70), and its relationship with the symptoms of ASD and attention deficit hyperactivity disorder (ADHD), using the Wechsler Intelligence Scale for Children-IV (WISC-IV). However, no data exist on the similarities or differences in this profile in less affluent countries. The present study examined the cognitive profile and its relationship with the symptoms of ASD and ADHD in 30 subjects aged 6–16 years with high-functioning ASD and compared the results with those of 30 typically developing (TD) subjects. In line with previous research findings, the WISC-IV cognitive profile analysis of subjects with high-functioning ASD showed a good competence in Matrix Reasoning and weaknesses in Comprehension, but the main distinguishing point was the competence in processing speed in both groups. In the present study, the Verbal Comprehension Index correlated negatively with the communication symptoms, and the Working Memory Index correlated positively with the social symptoms in the ASD group. Given the similarities that exist between the results of the present research and previous studies, it may be concluded that there are similarities in the cognitive profile of individuals with ASD.
Wound Healing Fluid Reflects the Inflammatory Nature and Aggressiveness of Breast Tumors
Authors: Agresti Roberto , Triulzi Tiziana , Sasso Marianna , Ghirelli Cristina , Aiello Piera , Rybinska Ilona , Campiglio Manuela , Sfondrini Lucia , Tagliabue Elda , Bianchi Francesca
Published: February 2019

Wound healing fluid that originates from breast surgery increases the aggressiveness of cancer cells that remain after the surgery. We determined the effects of the extent of surgery and tumor-driven remodeling of the surrounding microenvironment on the ability of wound-healing to promote breast cancer progression. In our analysis of a panel of 34 cytokines, chemokines, and growth factors in wound healing fluid, obtained from 27 breast carcinoma patients after surgery, the levels of several small molecules were associated with the extent of cellular damage that was induced by surgery. In addition, the composition of the resulting wound healing fluid was associated with molecular features of the removed tumor. Specifically, IP-10, IL-6, G-CSF, osteopontin, MIP-1a, MIP-1b, and MCP1-MCAF were higher in more aggressive tumors. Altogether, our findings indicate that the release of factors that are induced by removal of the primary tumor and subsequent wound healing is influenced by the extent of damage due to surgery and the reactive stroma that is derived from the continuously evolving network of interactions between neoplastic cells and the microenvironment, based on the molecular characteristics of breast carcinoma cells.
The Properties of Zn-Doped AlSb Thin Films Prepared by Pulsed Laser Deposition
Authors: Tang Ping , Wang Weimin , Li Bing , Feng Lianghuan , Zeng Guanggen
Published: February 2019

Aluminum antimony (AlSb) is a promising photovoltaic material with a band gap of about 1.62 eV. However, AlSb is highly deliquescent and not stable, which has brought great difficulties to the applications. Based on the above situation, there are two purposes for preparing our Zn-doped AlSb (AlSb:Zn) thin films: One is to make P-type AlSb and the other is to find a way to suppress the deliquescence of AlSb. The AlSb:Zn thin films were prepared on glass substrates at different substrate temperatures by using the pulsed laser deposition (PLD) method. The structural, surface morphological, optical, and electrical properties of AlSb:Zn films were investigated. The crystallization of AlSb:Zn thin films was enhanced and the electrical resistivity decreased as the substrate temperature increased. The scanning electron microscopy (SEM) images indicated that the grain sizes became bigger as the substrate temperatures increased. The Raman vibration mode AlSb:Zn films were located at ~107 and ~142 cm−1 and the intensity of Raman peaks was stronger at higher substrate temperatures. In the experiment, a reduced band gap (1.4 eV) of the AlSb:Zn thin film was observed compared to the undoped AlSb films, which were more suitable for thin-film solar cells. Zn doping could reduce the deliquescent speed of AlSb thin films. The fabricated heterojunction device showed the good rectification behavior, which indicated the PN junction formation. The obvious photovoltaic effect has been observed in an FTO/ZnS/AlSb:Zn/Au device.
Transparent p-Type Semiconductors: Copper-Based Oxides and Oxychalcogenides
Authors: Zhang Nengduo , Sun Jian , Gong Hao
Published: February 2019

While p-type transparent conducting materials (TCMs) are crucial for many optoelectronic applications, their performance is still not satisfactory. This has impeded the development of many devices such as photovoltaics, sensors, and transparent electronics. Among the various p-type TCMs proposed so far, Cu-based oxides and oxychalcogenides have demonstrated promising results in terms of their optical and electrical properties. Hence, they are the focus of this current review. Their basic material properties, including their crystal structures, conduction mechanisms, and electronic structures will be covered, as well as their device applications. Also, the development of performance enhancement strategies including doping/co-doping, annealing, and other innovative ways to improve conductivity will be discussed in detail.
Torsional Fretting Wear Behavior of PVD TiCN Coated CuNiAl Blade Bearing in Oil and Artificial Seawater
Authors: Zhang Po , Wang Jian
Published: February 2019

The feasibility of alleviating torsional fretting wear of the blade bearing by preparing PVD TiCN coating was studied. The results show that the friction torque was highly influenced by the wear debris acting as the solid lubricant. The TiCN coating reduced the wear volume by 97.6% and 62.3% in oil and artificial seawater, respectively, which was mainly due to an increase in surface hardness. In oil, the produced sulfates and phosphates prevent seizures between the friction pair and the worn surface was characterized by polishing wear. In artificial seawater, the wear mechanism was a combination of mechanical wear and corrosion wear. This study reveals that the TiCN coating is suitable for alleviation of fretting wear in the blade bearing.
SoS TextVis: An Extended Survey of Surveys on Text Visualization
Authors: Alharbi Mohammad , Laramee Robert S.
Published: February 2019

Text visualization is a rapidly growing sub-field of information visualization and visual analytics. There are many approaches and techniques introduced every year to address a wide range of challenges and analysis tasks, enabling researchers from different disciplines to obtain leading-edge knowledge from digitized collections of text. This can be challenging particularly when the data is massive. Additionally, the sources of digital text have spread substantially in the last decades in various forms, such as web pages, blogs, twitter, email, electronic publications, and digitized books. In response to the explosion of text visualization research literature, the first text visualization survey article was published in 2010. Furthermore, there are a growing number of surveys that review existing techniques and classify them based on text research methodology. In this work, we aim to present the first Survey of Surveys (SoS) that review all of the surveys and state-of-the-art papers on text visualization techniques and provide an SoS classification. We study and compare the 14 surveys, and categorize them into five groups: (1) Document-centered, (2) user task analysis, (3) cross-disciplinary, (4) multi-faceted, and (5) satellite-themed. We provide survey recommendations for researchers in the field of text visualization. The result is a very unique, valuable starting point and overview of the current state-of-the-art in text visualization research literature.
Resource Allocation Model for Sensor Clouds under the Sensing as a Service Paradigm
Authors: Guerreiro Joel , Rodrigues Luís , Correia Noélia
Published: February 2019

The Sensing as a Service is emerging as a new Internet of Things (IoT) business model for sensors and data sharing in the cloud. Under this paradigm, a resource allocation model for the assignment of both sensors and cloud resources to clients/applications is proposed. This model, contrarily to previous approaches, is adequate for emerging IoT Sensing as a Service business models supporting multi-sensing applications and mashups of Things in the cloud. A heuristic algorithm is also proposed having this model as a basis. Results show that the approach is able to incorporate strategies that lead to the allocation of fewer devices, while selecting the most adequate ones for application needs.
Crystal Structure of a Putative Modulator of Gyrase (TldE) from Thermococcus kodakarensis
Authors: Zhang Xin , Li Zhengqun , Zhao Yanxiang , Cheng Xilan , Liu Yang , Zhang Shihong , Liu Junfeng
Published: February 2019

TldD and TldE proteins interact and form a complex to degrade unfolded peptides. The gene Tk0499 from Thermococcus kodakarensis encoded a putative modulator of gyrase (TkTldE). Although TldE genes were common in bacteria and archaea, the structural basis on the evolution of proteins remained largely unknown. Here, the three-dimensional structure of TkTldE was determined by X-ray diffraction. Crystals were acquired by the sitting-drop vapor-diffusion method. X-ray diffraction data from crystals were collected at 2.35 Å. The space group and unit-cell parameters suggested that there were two molecules in the asymmetric unit. Our results showed that TkTldE forms a homodimer, which contained anti-parallel β-strands and a pair of α-helices. Comparison of the structures of TldE and TldD showed that despite their high sequence similarity, TldE lacked the conserved HExxxH and GxC motif in which two His and a Cys residues bound a metal ion. Taken together, these results provided insight into the structural information of this class of TldE/TldD.
Structure and Properties of 1,3-Phenylenediboronic Acid: Combined Experimental and Theoretical Investigations
Authors: Adamczyk-Woźniak Agnieszka , Cyrański Michał K. , Durka Krzysztof , Gozdalik Jan T. , Klimentowska Paulina , Rusiecki Rafał , Sporzyński Andrzej , Zarzeczańska Dorota
Published: February 2019

The structure and properties of 1,3-phenylenediboronic acid are reported. Molecular and crystal structures were determined by single crystal as well as by powder X-ray diffraction methods. Acidity constant, thermal behavior, and NMR characterization of the title compound were also investigated. In addition to the experimental data, calculations of rotational barrier and intermolecular interaction energies were performed. The compound reveals a two-step acid–base equilibrium with different pKa values. TGA and DSC measurements show a typical dehydration reaction with formation of boroxine. In crystals, hydrogen-bonded dimers with syn-anti conformation of hydroxyl groups form large numbers of ribbon motifs. The 2D potential energy surface scan of rotation of two boronic groups with respect to phenyl ring reveals that the rotation barrier is close to 37 kJ⋅mol−1, which is higher than the double value for the rotation of the boronic group in phenylboronic acid. This effect was ascribed to intermolecular interaction with C–H hydrogen atom located between boronic groups. Furthermore, the molecules in the crystal lattice adopt a less stable molecular conformation most likely resulting from intermolecular forces. These were further investigated by periodic DFT calculations supported by an estimation of dimer interaction energy, and also by topological analysis of electron density in the framework of AIM theory.
A Fast-Response and Helicity-Dependent Lens Enabled by Micro-Patterned Dual-Frequency Liquid Crystals
Authors: Duan Wei , Chen Peng , Ge Shi-Jun , Liang Xiao , Hu Wei
Published: February 2019

Liquid crystals are excellent candidates for tunable optical elements due to their large birefringence and continuous tunability by external fields. A dual-frequency liquid crystal lens integrated with Pancharatnam–Berry phase was fabricated via a dynamic photo-patterning technique. The proposed lens exhibited distinctive polarization-dependent characteristics and ultra-high efficiency rates of up to 95%. Via merely alternating the frequency of the applied electric field, the switching time between unfocused and focused states was measured in submilliseconds. This work supplies a new strategy for fast-response, high-efficiency and helicity-dependent lens with merits of easy fabrication and low power consumption.
Overexpression of AtWRKY30 Transcription Factor Enhances Heat and Drought Stress Tolerance in Wheat (Triticum aestivum L.)
Authors: El-Esawi Mohamed A. , Al-Ghamdi Abdullah A. , Ali Hayssam M. , Ahmad Margaret
Published: February 2019

Drought and heat factors have negative impacts on wheat yield and growth worldwide. Improving wheat tolerance to heat and drought stress is of the utmost importance to maintain crop yield. WRKY transcription factors help improve plant resistance to environmental factors. In this investigation, Arabidopsis WRKY30 (AtWRKY30) transcription factor was cloned and expressed in wheat. Plants growth, biomass, gas-exchange attributes, chlorophyll content, relative water content, prolines content, soluble proteins content, soluble sugars content, and antioxidant enzymes activities (catalase (CAT), superoxide dismutase (SOD), peroxidase (POX), and ascorbate peroxidase (APX)) of the AtWRKY30-overexpressing wheat plants were higher than those of the wild type. However, levels of electrolyte leakage, malondialdehyde, and hydrogen peroxide of the AtWRKY30-overexpressing wheat plants were significantly less than those of the wild-type. Additionally, the expression level of antioxidant enzyme-encoding genes and stress-responsive genes (ERF5a, DREB1, DREB3, WRKY19, TIP2, and AQP7) were significantly induced in the transgenic wheat plants in comparison with the wild type. In conclusion, the results demonstrated that AtWRKY30 overexpression promotes heat and drought tolerance in wheat by inducing gas-exchange attributes, antioxidant machinery, osmolytes biosynthesis, and stress-related gene expression. AtWRKY30 could serve as a potential candidate gene for improving stress tolerance in wheat.
Hand Hygiene Compliance Study at a Large Central Hospital in Vietnam
Authors: Le Cam Dung , Lehman Erik B. , Nguyen Thanh Huy , Craig Timothy J.
Published: February 2019

Lack of proper hand hygiene among healthcare workers has been identified as a core facilitator of hospital-acquired infections. Although the concept of hand hygiene quality assurance was introduced to Vietnam relatively recently, it has now become a national focus in an effort to improve the quality of care. Nonetheless, barriers such as resources, lack of education, and cultural norms may be limiting factors for this concept to be properly practiced. Our study aimed to assess the knowledge and attitude of healthcare workers toward hand hygiene and to identify barriers to compliance, as per the World Health Organization’s guidelines, through surveys at a large medical center in Vietnam. In addition, we aimed to evaluate the compliance rate across different hospital departments and the roles of healthcare workers through direct observation. Results showed that, in general, healthcare workers had good knowledge of hand hygiene guidelines, but not all believed in receiving reminders from patients. The barriers to compliance were identified as: limited resources, patient overcrowding, shortage of staff, allergic reactions to hand sanitizers, and lack of awareness. The overall compliance was 31%; physicians had the lowest rate of compliance at 15%, while nurses had the highest rate at 39%; internal medicine had the lowest rate at 16%, while the intensive care unit had the highest rate at 40%. In summary, it appears that addressing cultural attitudes in addition to enforcing repetitive quality assurance and assessment programs are needed to ensure adherence to safe hand washing.
Towards the Development of Artificial Bone Grafts: Combining Synthetic Biomineralisation with 3D Printing
Authors: Kurian Mima , Stevens Ross , McGrath Kathryn M
Published: February 2019

A synthetic technique inspired by the biomineralisation process in nacre has been previously reported to be effective in replicating the nanostructural elements of nacre in 2D chitosan hydrogel films. Here we evaluate the applicability of this synthetic biomineralisation technique, herein called the McGrath method, in replicating the flat tabular morphology of calcium carbonate and other nanostructural elements obtained when 2D chitosan hydrogel films were used, on a 3D porous chitosan hydrogel-based scaffold, hence developing 3D chitosan-calcium carbonate composites. Nozzle extrusion-based 3D printing technology was used to develop 3D porous scaffolds using chitosan hydrogel as the printing ink in a custom-designed 3D printer. The rheology of the printing ink and print parameters were optimised in order to fabricate 3D cylindrical structures with a cubic lattice-based internal structure. The effects of various dehydration techniques, including air-drying, critical point-drying and freeze-drying, on the structural integrity of the as-printed scaffolds from the nano to macroscale, were evaluated. The final 3D composite materials were characterised using scanning electron microscopy, X-ray diffraction and energy dispersive X-ray spectroscopy. The study has shown that McGrath method can be used to develop chitosan-calcium carbonate composites wherein the mineral and matrix are in intimate association with each other at the nanoscale. This process can be successfully integrated with 3D printing technology to develop 3D compartmentalised polymer-mineral composites.
Stephen Jay Gould’s Analysis of the Army Beta Test in The Mismeasure of Man: Distortions and Misconceptions Regarding a Pioneering Mental Test
Authors: Warne Russell T. , Burton Jared Z. , Gibbons Aisa , Melendez Daniel A.
Published: February 2019

In The Mismeasure of Man, Stephen Jay Gould argued that the preconceived beliefs and biases of scientists influence their methods and conclusions. To show the potential consequences of this, Gould used examples from the early days of psychometrics and allied fields, arguing that inappropriate assumptions and an elitist desire to rank individuals and/or groups produced incorrect results. In this article, we investigate a section of The Mismeasure of Man in which Gould evaluated the Army Beta intelligence test for illiterate American draftees in World War I. We evaluated Gould’s arguments that the Army Beta (a) had inappropriate content, (b) had unsuitable administration conditions, (c) suffered from short time limits, and (d) could not have measured intelligence. By consulting the historical record and conducting a pre-registered replication of Gould’s administration of the test to a sample of college students, we show that Gould mischaracterized the Army Beta in a number of ways. Instead, the Army Beta was a well-designed test by the standards of the time, and all evidence indicates that it measured intelligence a century ago and can, to some extent, do so today.
A Fresh View on the Microarchitectural Design of FPGA-Based RISC CPUs in the IoT Era
Authors: Scotti Giovanni , Zoni Davide
Published: February 2019

The Internet-of-Things (IoT) revolution has shaped a new application domain where low-power RISC architectures constitute the standard computational backbone. The current de-facto design practice for such architectures is to extend the ISA and the corresponding microarchitecture with custom instructions to efficiently manage the complex tasks imposed by IoT applications, i.e., augmented reality, artificial intelligence and autonomous driving, within narrow energy and area budgets. However, the new IoT application domain also offers a unique opportunity to revisit and optimize the RISC microarchitectural design flow from a more communication- and memory-centric viewpoint. This manuscript critically explores and optimizes the design of a RISC CPU front-end for IoT delivering a two-fold objective: (i) provide an optimized CPU microarchitecture; and (ii) present a set of three design guidelines to steer the implementation of IoT CPUs. The exploration sits on a newly proposed Systems-on-Chip (SoC) and RISC CPU implementing the RISC-V/IMF ISA and accounting for area, timing, and performance design metrics. Such SoC offers a reference design to evaluate pros and cons of different microarchitectural solutions. A wide combination of microarchitectures considering different branch prediction schemes, cache design architectures and on-chip bus solutions have been evaluated. The entire exploration is focused on the FPGA-based implementation due to the renewed interest for this technology demonstrated by both the research community and companies. We note that ARM launched the DesignStart FPGA program to make available the Cortex-M microcontrollers on Xilinx FPGAs in the form of IP blocks.
Transient Effects in Creep of Sanicro 25 Austenitic Steel and Their Modelling
Authors: Kloc Luboš , Sklenička Václav , Dymáček Petr
Published: February 2019

Transient effects upon stress changes during creep of the new Sanicro 25 steel were investigated experimentally using the helicoid spring specimen technique. The creep behaviour was found to be qualitatively the same as that observed earlier with the creep-resistant 9% Cr ferritic-martensitic P-91 steel, but the transient strains are considerably smaller. Negative creep rate, which is strain running against the applied stress, was observed with any stress decrease. Parameters for the complex creep model were estimated and model results were compared to the creep rates measured experimentally. The model can be used for the finite element method modelling of the creep and stress relaxation effects in the components made from the Sanicro 25 steel.
Properties of Jet-Plated Ni Coating on Ti Alloy (Ti6Al4V) with Laser Cleaning Pretreatment
Authors: Wang Xiao , Xu Mingyang , Wang Zhanwen , Shen Lida , Qiu Mingbo , Tian Zongjun , Ahsan Muhammad Naveed , Wang Changjiang
Published: February 2019

The surface mechanical properties of the Selective Laser Melting (SLM) formed Ti6Al4V samples were improved by adopting a novel laser cleaning pretreatment process combined with a jet electrodeposition process. This paper aimed to investigate the effects of different laser powers on the morphologies and adhesions of the nickel coatings. The advantages of the laser cleaning process are no grinding, no contact, high efficiency and environmental protection. The morphologies, adhesion, wear resistance, and hardness of the coatings were characterized. The results indicate that when the laser energy density reached 20% (4 J/cm2), the contaminations on the substrate and the oxide layer were removed and the crystalline grain of the coating was 15.3 nm. The shallow pits generated by laser burning increased the adhesion of the coatings. In addition, when the laser energy density increased to 6 J/cm2, a yellow oxide layer was produced on the surface of the cleaned titanium alloy. Moreover, the wear resistance of the titanium alloy after the nickel plating was improved. The wear volume was only 0.046 mm3, and the hardness increased to 1967.6 N/mm2.
Microstructure-Based Constitutive Modelling of Low-Alloy Multiphase TRIP Steels
Authors: Salinas Álvaro , Celentano Diego , Carvajal Linton , Artigas Alfredo , Monsalve Alberto
Published: February 2019

The microstructure of low-alloy multiphase transformation-induced plasticity (TRIP) steels consists of ferrite, bainite, and metastable retained austenite, which can be transformed into martensite by plastic deformation. In some cases, residual martensite can be present in the initial microstructure. The mechanical behavior of these steels depends on the interaction between the intrinsic characteristics of the existing phases and the austenite stability. Due to these factors, the definition of their true stress-strain flow law is complex. This work presents the mechanical characterization of a phenomenological constitutive stress-strain flow law based on the Bouquerel et al. model, as evaluated for three TRIP steels of the same composition but undergoing different heat treatments. Morphological aspects of the existing phases, austenite stability, and suitable mixture laws between phases are considered. The model is found to accurately reproduce a true stress-strain flow law obtained under tensile uniaxial conditions and provide detailed information on the effective stress strain partition between the existing phases.
A Review of Multi-Scale Computational Modeling Tools for Predicting Structures and Properties of Multi-Principal Element Alloys
Authors: Beyramali Kivy Mohsen , Hong Yu , Asle Zaeem Mohsen
Published: February 2019

Multi-principal element (MPE) alloys can be designed to have outstanding properties for a variety of applications. However, because of the compositional and phase complexity of these alloys, the experimental efforts in this area have often utilized trial and error tests. Consequently, computational modeling and simulations have emerged as power tools to accelerate the study and design of MPE alloys while decreasing the experimental costs. In this article, various computational modeling tools (such as density functional theory calculations and atomistic simulations) used to study the nano/microstructures and properties (such as mechanical and magnetic properties) of MPE alloys are reviewed. The advantages and limitations of these computational tools are also discussed. This study aims to assist the researchers to identify the capabilities of the state-of-the-art computational modeling and simulations for MPE alloy research.
Research on a Dual-Mode Infrared Liquid-Crystal Device for Simultaneous Electrically Adjusted Filtering and Zooming
Authors: Liu Zhonglun , Chen Mingce , Xin Zhaowei , Dai Wanwan , Han Xinjie , Zhang Xinyu , Wang Haiwei , Xie Changsheng
Published: February 2019

A new dual-mode liquid-crystal (LC) micro-device constructed by incorporating a Fabry–Perot (FP) cavity and an arrayed LC micro-lens for performing simultaneous electrically adjusted filtering and zooming in infrared wavelength range is presented in this paper. The main micro-structure is a micro-cavity consisting of two parallel zinc selenide (ZnSe) substrates that are pre-coated with ~20-nm aluminum (Al) layers which served as their high-reflection films and electrodes. In particular, the top electrode of the device is patterned by 44 × 38 circular micro-holes of 120 μm diameter, which also means a 44 × 38 micro-lens array. The micro-cavity with a typical depth of ~12 μm is fully filled by LC materials. The experimental results show that the spectral component with needed frequency or wavelength can be selected effectively from incident micro-beams, and both the transmission spectrum and the point spread function can be adjusted simultaneously by simply varying the root-mean-square value of the signal voltage applied, so as to demonstrate a closely correlated feature of filtering and zooming. In addition, the maximum transmittance is already up to ~20% according the peak-to-valley value of the spectral transmittance curves, which exhibits nearly twice the increment compared with that of the ordinary LC-FP filtering without micro-lenses.
Fentanyl Family at the Mu-Opioid Receptor: Uniform Assessment of Binding and Computational Analysis
Authors: Lipiński Piotr F. J. , Kosson Piotr , Matalińska Joanna , Roszkowski Piotr , Czarnocki Zbigniew , Jarończyk Małgorzata , Misicka Aleksandra , Dobrowolski Jan Cz. , Sadlej Joanna
Published: February 2019

Interactions of 21 fentanyl derivatives with μ-opioid receptor (μOR) were studied using experimental and theoretical methods. Their binding to μOR was assessed with radioligand competitive binding assay. A uniform set of binding affinity data contains values for two novel and one previously uncharacterized derivative. The data confirms trends known so far and thanks to their uniformity, they facilitate further comparisons. In order to provide structural hypotheses explaining the experimental affinities, the complexes of the studied derivatives with μOR were modeled and subject to molecular dynamics simulations. Five common General Features (GFs) of fentanyls’ binding modes stemmed from these simulations. They include: GF1) the ionic interaction between D147 and the ligands’ piperidine NH+ moiety; GF2) the N-chain orientation towards the μOR interior; GF3) the other pole of ligands is directed towards the receptor outlet; GF4) the aromatic anilide ring penetrates the subpocket formed by TM3, TM4, ECL1 and ECL2; GF5) the 4-axial substituent (if present) is directed towards W318. Except for the ionic interaction with D147, the majority of fentanyl-μOR contacts is hydrophobic. Interestingly, it was possible to find nonlinear relationships between the binding affinity and the volume of the N-chain and/or anilide’s aromatic ring. This kind of relationships is consistent with the apolar character of interactions involved in ligand–receptor binding. The affinity reaches the optimum for medium size while it decreases for both large and small substituents. Additionally, a linear correlation between the volumes and the average dihedral angles of W293 and W133 was revealed by the molecular dynamics study. This seems particularly important, as the W293 residue is involved in the activation processes. Further, the Y326 (OH) and D147 (Cγ) distance found in the simulations also depends on the ligands’ size. In contrast, neither RMSF measures nor D114/Y336 hydrations show significant structure-based correlations. They also do not differentiate studied fentanyl derivatives. Eventually, none of 14 popular scoring functions yielded a significant correlation between the predicted and observed affinity data (R < 0.30, n = 28).
Chlamyphilone, a Novel Pochonia chlamydosporia Metabolite with Insecticidal Activity
Authors: Lacatena Federica , Marra Roberta , Mazzei Pierluigi , Piccolo Alessandro , Digilio Maria Cristina , Giorgini Massimo , Woo Sheridan L. , Cavallo Pierpaolo , Lorito Matteo , Vinale Francesco
Published: February 2019

Metabolites from a collection of selected fungal isolates have been screened for insecticidal activity against the aphid Acyrthosiphon pisum. Crude organic extracts of culture filtrates from six fungal isolates (Paecilomyces lilacinus, Pochonia chlamydosporia, Penicillium griseofulvum, Beauveria bassiana, Metarhizium anisopliae and Talaromyces pinophilus) caused mortality of aphids within 72 h after treatment. In this work, bioassay-guided fractionation has been used to characterize the main bioactive metabolites accumulated in fungal extracts. Leucinostatins A, B and D represent the bioactive compounds produced by P. lilacinus. From P. griseofulvum and B. bassiana extracts, griseofulvin and beauvericin have been isolated, respectively; 3-O-Methylfunicone and a mixture of destruxins have been found in the active fractions of T. pinophilum and M. anisopliae, respectively. A novel azaphilone compound, we named chlamyphilone, with significant insecticidal activity, has been isolated from the culture filtrate of P. chlamydosporia. Its structure has been determined using extensive spectroscopic methods and chemical derivatization.
Lateral Flow Aptasensor for Simultaneous Detection of Platelet-Derived Growth Factor-BB (PDGF-BB) and Thrombin
Authors: Liu Guodong , Gurung Anant S , Qiu Wanwei
Published: February 2019

Here we report a lateral flow aptasensor (LFA) for the simultaneous detection of platelet-derived growth factor-BB (PDGF-BB) and thrombin. Two pairs of aptamers, which are specific against PDGF-BB and thrombin, respectively, were used to prepare the LFA. Thiolated aptamers were immobilized on a gold nanoparticle (AuNP) surface and biotinylated aptamers were immobilized on the test zones of an LFA nitrocellulose membrane. The assay involved the capture of PDGF-BB and thrombin simultaneously in sandwich-type formats between the capture aptamers on the test zones of LFA and AuNP-labeled detection aptamers. AuNPs were thus captured on the test zones of the LFA and gave red bands to enable the visual detection of target proteins. Quantitative results were obtained by reading the test band intensities with a portable strip reader. By combining the highly specific molecular recognition properties of aptamers with the unique properties of lateral flow assay (low-cost, short assay time and a user-friendly format), the optimized aptasensor was capable of simultaneously detecting 1.0 nM of PDGF-BB and 1.5 nM of thrombin in association with a 10-min assay time. The biosensor was also successfully applied to detect PDGF-BB and thrombin in spiked human serum samples. The LFA shows great promise for the development of aptamer-based lateral flow strip biosensors for point-of-care or for the in-field detection of disease-related protein biomarkers.
Electrospun Polyvinyl Alcohol/d-Limonene Fibers Prepared by Ultrasonic Processing for Antibacterial Active Packaging Material
Authors: Lan Weijie , Liang Xue , Lan Wenting , Ahmed Saeed , Liu Yaowen , Qin Wen
Published: February 2019

Novel fibers containing different ratios of PVA and d-limonene were fabricated using electrospinning for antibacterial active packaging applications. The PVA/d-limonene fibers were thoroughly characterized using a scanning electron microscope, fourier-transform infrared spectrometry, thermal gravimetry, differential scanning calorimetry, tensile tests, and oxygen permeability tests. The results of these analyses showed that the highest tensile strength and elongation at break values of 3.87 ± 0.25 MPa and 55.62 ± 2.93%, respectively, were achieved for a PVA/d-limonene ratio of 7:3 (v/v) and an ultrasonication time of 15 min during processing. This material also showed the lowest oxygen permeation and the best degradability and bacteriostatic properties of all samples.
Multi-Level Cell Properties of a Bilayer Cu2O/Al2O3 Resistive Switching Device
Authors: Deuermeier Jonas , Kiazadeh Asal , Klein Andreas , Martins Rodrigo , Fortunato Elvira
Published: February 2019

Multi-level resistive switching characteristics of a Cu2O/Al2O3 bilayer device are presented. An oxidation state gradient in copper oxide induced by the fabrication process was found to play a dominant role in defining the multiple resistance states. The highly conductive grain boundaries of the copper oxide—an unusual property for an oxide semiconductor—are discussed for the first time regarding their role in the resistive switching mechanism.
Thioredoxin Reductase Activity Predicts Gold Nanoparticle Radiosensitization Effect
Authors: Penninckx Sébastien , Heuskin Anne-Catherine , Michiels Carine , Lucas Stéphane
Published: February 2019

Gold nanoparticles (GNPs) have been shown to be effective contrast agents for imaging and emerge as powerful radiosensitizers, constituting a promising theranostic agent for cancer. Although the radiosensitization effect was initially attributed to a physical mechanism, an increasing number of studies challenge this mechanistic hypothesis and evidence the importance of oxidative stress in this process. This work evidences the central role played by thioredoxin reductase (TrxR) in the GNP-induced radiosensitization. A cell type-dependent reduction in TrxR activity was measured in five different cell lines incubated with GNPs leading to differences in cell response to X-ray irradiation. Correlation analyses demonstrated that GNP uptake and TrxR activity inhibition are associated to a GNP radiosensitization effect. Finally, Kaplan-Meier analyses suggested that high TrxR expression is correlated to low patient survival in four different types of cancer. Altogether, these results enable a better understanding of the GNP radiosensitization mechanism, which remains a mandatory step towards further use in clinic. Moreover, they highlight the potential application of this new treatment in a personalized medicine context.
Phased-Array Radar System Simulator (PASIM): Development and Simulation Result Assessment
Authors: Li Zhe , Perera Sudantha , Zhang Yan , Zhang Guifu , Doviak Richard
Published: February 2019

In this paper, a system-specific phased-array radar system simulator was developed, based on a time-domain modeling and simulation method, mainly for system performance evaluation of the future Spectrum-Efficient National Surveillance Radar (SENSR). The goal of the simulation study was to establish a complete data quality prediction method based on specific radar hardware and electronics designs. The distributed weather targets were modeled using a covariance matrix-based method. The data quality analysis was conducted using Next-Generation Radar (NEXRAD) Level-II data as a basis, in which the impact of various pulse compression waveforms and channel electronic instability on weather radar data quality was evaluated. Two typical weather scenarios were employed to assess the simulator’s performance, including a tornado case and a convective precipitation case. Also, modeling of some demonstration systems was evaluated, including a generic weather radar, a planar polarimetric phased-array radar, and a cylindrical polarimetric phased-array radar. Corresponding error statistics were provided to help multifunction phased-array radar (MPAR) designers perform trade-off studies.
Statistical Characteristics of Raindrop Size Distribution in the Monsoon Season Observed in Southern China
Authors: Zhang Asi , Hu Junjun , Chen Sheng , Hu Dongming , Liang Zhenqing , Huang Chaoying , Xiao Liusi , Min Chao , Li Haowen
Published: February 2019

This study investigates the statistical characteristics of raindrop size distributions (DSDs) in monsoon season with observations collected by the second-generation Particle Size and Velocity (Parsivel2) disdrometer located in Zhuhai, southern China. The characteristics are quantified based on convective and stratiform precipitation classified using the rainfall intensity and total number of drops. On average of the whole dataset, the DSD characteristic in southern China consists of a higher number concentration of relatively small-sized drops when compare with eastern China and northern China, respectively. In the meanwhile, the Dm and log10Nw scatter plots prove that the convective rain in monsoon season can be identified as maritime-like cluster. The DSD is in good agreement with a three-parameter gamma distribution, especially for the medium to large raindrop size. Using filtered data observed by Parsivel2 disdrometer, a new Z–R relationship, Z = 498R1.3, is derived for convective rain in monsoon season in southern China. These results offer insights of the microphysical nature of precipitation in Zhuhai during monsoon season, and provide essential information that may be useful for precipitation retrievals based on weather radar observations.
A Fine Velocity and Strain Rate Field of Present-Day Crustal Motion of the Northeastern Tibetan Plateau Inverted Jointly by InSAR and GPS
Authors: Song Xiaogang , Jiang Yu , Shan Xinjian , Gong Wenyu , Qu Chunyan
Published: February 2019

Interferometric synthetic aperture radar (InSAR) data from 6 Envisat ASAR descending tracks; spanning the 2003–2010 period; was used to measure interseismic strain accumulation across the Northeastern Tibetan Plateau. Mean line-of-sight (LOS) ratemaps are computed by stacking atmospheric-corrected and orbital-corrected interferograms. The ratemaps from one track with different atmospheric-corrected results or two parallel; partially overlapping tracks; show a consistent pattern of left-lateral motion across the fault; which demonstrates the MERIS and ECMWF atmospheric correction works satisfactorily for small stain measurement of this region; even with a limited number of interferograms. By combining the measurements of InSAR and GPS; a fine crustal deformation velocity and strain rate field was estimated on discrete points with irregular density depending on the fault location; which revealed that the present-day slip rate on the Haiyuan fault system varies little from west to east. A change (2–3 mm/year) in line-of-sight (LOS) deformation rate across the fault is observed from the Jinqianghe segment to its eastern end. Inversion from the cross-fault InSAR profiles gave a shallow locking depth of 3–6 km on the main rupture of the 1920 earthquake. We therefore infer that the middle-lower part of the seismogenic layer on the 1920 rupture is not yet fully locked since the 1920 large earthquake. Benefit from high spatial resolution InSAR data; a low strain accumulation zone with high strain rates on its two ends was detected; which corresponds to the creeping segment; i.e., the Laohushan fault segment. Contrary to the previous knowledge of squeezing structure; an abnormal tension zone is disclosed from the direction map of principal stress; which is consistent with the recent geological study. The distribution of principal stress also showed that the expanding frontier of the northeastern plateau has crossed the Liupan Shan fault zone; even arrived at the northeast area of the Xiaoguan Shan. This result agrees with the deep seismic reflection profile.
Biogenic Amines in Traditional Fiore Sardo PDO Sheep Cheese: Assessment, Validation and Application of an RP-HPLC-DAD-UV Method
Authors: Zazzu Claudia , Addis Margherita , Caredda Marco , Scintu Maria Francesca , Piredda Giovanni , Sanna Gavino
Published: February 2019

This contribution aimed to measure for the first time the amount of biogenic amines (BAs) in one of the most ancient and traditional sheep cheese produced in Sardinia, Italy: the Protected Designation of Origin (PDO) Fiore Sardo. To achieve this, an original RP-HPLC-DAD-UV method has been developed that was completely validated in terms of LoD, LoQ, linearity, precision and trueness, and tested on 36 real Fiore Sardo PDO cheese samples produced by four different cheesemakers and marketed by four stores. The average total concentration of the eight BAs (i.e., tyramine, tryptamine, histidine, putrescine, cadaverine, 2-phenylethylamine, spermine and spermidine) measured in Fiore Sardo cheese was 700 mg/kg, with a range between 170 mg/kg and 1100 mg/kg. A great variability in the total amount of BAs has been evidenced among the Fiore Sardo marketed in the four stores as well as for the cheeses purchased in different times in the same store. Tyramine (350 mg/kg), putrescine (150 mg/kg), histamine (80 mg/kg) and cadaverine (30 mg/kg) are the most abundant BAs found in this matrix. Among the many factors concurring, the dominant microflora of Fiore Sardo PDO is likely the principal cause of the qualitative and quantitative distribution of BAs in this matrix. Finally, the total amount of BAs found in Fiore Sardo PDO is not able to cause any health alert situation for consumers.
Nutrition Labeling Schemes and the Time and Effort of Consumer Processing
Authors: Alonso-Dos-Santos Manuel , Quilodrán Ulloa René , Salgado Quintana Álvaro , Vigueras Quijada Diego , Farías Nazel Pablo
Published: February 2019

Guideline Daily Amount (GDA) and nutrition tables are the most used front-of-pack (FOP) nutrition labeling schemes in the world; however, they are hard to process considering the nutritional knowledge, effort, and time needed for interpretation. Consumers spend little time and effort evaluating food products. Consumers are selective, and FOP nutrition labeling schemes should be too. Recent studies have shown that warning messages—a new FOP nutrition labeling scheme—improves consumers’ ability to correctly identify less-healthy products. This study proposes that warning messages are also easier to process. Using eye-tracking, this study demonstrates that warning messages require less processing effort and time than GDA and nutrition tables. This study also shows that females process warning messages easier than males. Additionally, this study found no significant differences between physically active and inactive consumers in their processing of warning messages. The results are robust across product categories and brands.
Long-term use of benzodiazepines and Z drugs: a qualitative study of patients’ and healthcare professionals’ perceptions and possible levers for change
Authors: Mokhar Aliaksandra , Kuhn Silke , Topp Janine , Dirmaier Jörg , Härter Martin , Verthein Uwe
Published: February 2019

Background

Although long-term use of benzodiazepines (BZDs) and Z drugs is associated with various side effects, they remain popular among the older population. Possible reasons for this phenomenon could be ineffective ways of transmitting information on the health risks associated with long-term use, and communication gaps between patients and healthcare professionals.

Aim

The aim was to investigate the views of patients, physicians, nurses, and pharmacists regarding long-term BZD and Z drug use.

Design & setting

The qualitative study design used focus group interviews with physicians, pharmacists, and nurses in Hamburg. Patient interviews were conducted in Lippstadt, Germany.

Method

The interviews were audiotaped with each participant’s permission, transcribed, and thematically analysed using a software program for qualitative research (MAXQDA).

Results

The data from the four focus groups consisting of 28 participants were analysed. Patients indicated lack of knowledge about risks and side effects, difficult access to alternatives, and fears of ceasing drug use without professional support. Although the physicians were reported to be cautious about prescribing BZDs and Z drugs, the psychosocial problems of older patients are often considered to be complex and treatment knowledge, experience, and resources are frequently unsatisfactory. Nurses described that when BZDs were prescribed, they did not feel it was their responsibility to evaluate their effects. Pharmacists were reported to be strongly ambivalent in informing patients about the risks, which may contradict the prescription advice provided by the physician.

Conclusion

Patients, physicians, nurses, and pharmacists reported differences in the perception of long-term BZD and Z drug use. Nevertheless, all of the participants described lack of information and expressed the need for greater communication exchange.