bluuebunny/crossref_metadata_2025 huggingface dataset:
A Novel Connectivity Factor for Morphological Characterization of Membranes and Porous Media: A Simulation Study on Structures of Mono-Sized Spherical Particles
Authors: Bellini Stefano , Azzato Giulia , Grandinetti Monia , Stellato Virgilio , De Marco Giuseppe , Sun Yu , Caravella Alessio
Published: April 2018

In this study, we propose to define a connectivity factor as the inverse of the diffusional tortuosity to measure quantitatively the connectivity of whatever type of structure. The concept of connectivity used here is related to the diffusional accessibility of the structure voids. This definition of connectivity factor arises from the consideration that, if we ideally imagine to decrease progressively the porosity of a regular structure, the porosity itself reaches a limit value below which the inner pores are not interconnected anymore. This leads to an evident situation of zero connectivity and infinite tortuosity, where there is no continuous diffusion path able to connect the structure voids. According to the proposed definition, the connectivity factor is comprised within [0, 1], with zero corresponding to a completely disconnected structure and unity to a completely connected one. To show the efficacy of the presented approach, a case study on the regular structure of mono-sized (mono-disperse) spherical particles (Simple Cubic (SC), Face-Centred Cubic (FCC), Body-Centred Cubic (BCC) and Tetragonal structures) is provided. In particular, the tortuosity of such structures is evaluated by Computational Fluid Dynamics simulations, calculating the connectivity factor consequently. The morphological modification with porosity is induced by changing the surface–surface interparticle distance, allowing us to take both positive (detached particles) and negative values (overlapping particles). For each structure, a comparison between the calculated trends and some correlations of literature is made, and a novel “hidden” morphological parameter has been identified, that is, the here-called Limit Porosity Value, below which the connectivity is zero. The presented approach represents a systematic methodology to quantify the connectivity of any structure and to compare the morphology of membranes, catalysts, and porous media in general.
Interface Characteristics of Ti-Clad V–4Cr–4Ti Alloy Diffusion-Bonded Joint Produced by Hot Forging
Authors: Zhang Gaowei , Han Wentuo , Yi Xiaoou , Wan Farong
Published: April 2018

Diffusion bonding of V–4Cr–4Ti alloy to pure titanium (Ti) was carried out by hot forging in the temperature range between 1150 °C and 950 °C. The microstructure and mechanical properties of the bonded joint were determined by using light optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), micro-hardness measurements, and shear tests. The results indicate that the sound dissimilar joint can be obtained through hot forging processes. The interface has a width of about 100 μm and can be divided into two distinctive zones: a Widmanstatten structure zone and a β-Ti phase structure zone. According to the micro-hardness distribution profile across the substrates and the interface, the largest hardness of 332 HV was measured in a narrow region between the Ti substrate and the joint, which is remarkably higher than that of the substrates (Ti of 190 HV and V–4Cr–4Ti alloy of 258 HV). The lowest hardness of only 182 HV was found in a region in the V–4Cr–4Ti substrate adjacent to the joint. The shear test showed that the joint has a bonding strength higher than 165 MPa and a fracture of the joint took place in the region with the highest hardness.
Actively Controlling the Topological Transition of Dispersion Based on Electrically Controllable Metamaterials
Authors: Guo Zhiwei , Jiang Haitao , Sun Yong , Li Yunhui , Chen Hong
Published: April 2018

Topological transition of the iso-frequency contour (IFC) from a closed ellipsoid to an open hyperboloid provides unique capabilities for controlling the propagation of light. However, the ability to actively tune these effects remains elusive, and the related experimental observations are highly desirable. Here, a tunable electric IFC in a periodic structure composed of graphene/dielectric multilayers is investigated by tuning the chemical potential of the graphene layer. Specially, we present the actively controlled transportation in two kinds of anisotropic zero-index media containing perfect electric conductor/perfect magnetic conductor impurities. Finally, by adding variable capacitance diodes into a two-dimensional transmission-line system, we present an experimental demonstration of the actively controlled magnetic topological transition of dispersion based on electrically controllable metamaterials. With the increase in voltage, we measure the different emission patterns from a point source inside the structure and observe the phase-transition process of IFCs. The realization of an actively tuned topological transition will open up a new avenue in the dynamical control of metamaterials.
Investigation on the Effects of Internal EGR by Variable Exhaust Valve Actuation with Post Injection on Auto-ignited Combustion and Emission Performance
Authors: Cho Insu , Lee Yumin , Lee Jinwook
Published: April 2018

Variable valve mechanisms are usually applied to a gasoline combustion engine to improve its power performance by controlling the amount of intake air according to the operating load. These mechanisms offer one possibility of resolving the conflict of objectives between a further reduction of raw emissions and an improvement in fuel efficiency. In recent years, variable valve control systems have become extremely important in the diesel combustion engine. Importantly, it has been shown that there are several potential benefits of applying variable valve timing (VVT) to a compression ignition engine. Valve train variability could offer one option to achieve the reduction goals of engine-out emissions and fuel consumption. The aim of this study was to investigate the effects on part load combustion and emission performance of internal exhaust gas recirculation (EGR) by variable exhaust valve lift actuation using a cam-in-cam system, which is an electronically variable valve device with a variable inside cam retarded to about 30 degrees. Numerical simulation based on GT-POWER has been performed to predict the NOx reduction strategy at the part load operating point of 1200 rpm in a four-valve diesel engine. A GT-POWER model of a common-rail direct injection engine with internal EGR was built and verified with experimental data. As a result, large potential for reducing NOx emissions through the use of exhaust valve control has been identified. Namely, it is possible to utilize heat efficiently as recompression of retarded post injection with downscaled specification of the exhaust valve rather than the intake valve, even if the CIC V1 condition with a reduction of the exhaust valve has a higher internal EGR rate of about 2% compared to that of the CIC V2 condition.
Studying Antimatter Gravity with Muonium
Authors: Antognini Aldo , Kaplan Daniel , Kirch Klaus , Knecht Andreas , Mancini Derrick , Phillips James , Phillips Thomas , Reasenberg Robert , Roberts Thomas , Soter Anna
Published: April 2018

The gravitational acceleration of antimatter, g ¯ , has yet to be directly measured; an unexpected outcome of its measurement could change our understanding of gravity, the universe, and the possibility of a fifth force. Three avenues are apparent for such a measurement: antihydrogen, positronium, and muonium, the last requiring a precision atom interferometer and novel muonium beam under development. The interferometer and its few-picometer alignment and calibration systems appear feasible. With 100 nm grating pitch, measurements of g ¯ to 10%, 1%, or better can be envisioned. These could constitute the first gravitational measurements of leptonic matter, of 2nd-generation matter, and possibly, of antimatter.
Influence of the p ¯ -p Nuclear Interaction on the Rate of the Low-Energy p ¯	+	H μ	→	( p ¯ p ) α + μ − Reaction
Authors: Sultanov Renat , Guster Dennis , Adhikari Sadhan
Published: April 2018

The influence of an additional strong p ¯ -p nuclear interaction in a three-charge-particle system with arbitrary masses is investigated. Specifically, the system of p ¯ , μ − , and p is considered in this paper, where p ¯ is an antiproton, μ − is a muon and p is a proton. A numerical computation in the framework of a detailed few-body approach is carried out for the following protonium (antiprotonic hydrogen) formation three-body reaction: p ¯ + H μ ( 1 s ) → ( p ¯ p ) α + μ − . Here, H μ ( 1 s ) is a ground state muonic hydrogen, i.e., a bound state of p and μ − . A bound state of p and its antimatter counterpart p ¯ is a protonium atom in a quantum atomic state α , i.e., P n = ( p ¯ p ) α . The low-energy cross sections and rates of the P n formation reaction are computed in the framework of coupled Faddeev-Hahn-type equations. The strong p ¯ -p interaction is included in these calculations within a first order approximation. It was found, that the inclusion of the nuclear interaction results in a quite significant correction to the rate of the three-body reaction.
Fog Computing and the Internet of Things: A Review
Authors: Atlam Hany , Walters Robert , Wills Gary
Published: April 2018

With the rapid growth of Internet of Things (IoT) applications, the classic centralized cloud computing paradigm faces several challenges such as high latency, low capacity and network failure. To address these challenges, fog computing brings the cloud closer to IoT devices. The fog provides IoT data processing and storage locally at IoT devices instead of sending them to the cloud. In contrast to the cloud, the fog provides services with faster response and greater quality. Therefore, fog computing may be considered the best choice to enable the IoT to provide efficient and secure services for many IoT users. This paper presents the state-of-the-art of fog computing and its integration with the IoT by highlighting the benefits and implementation challenges. This review will also focus on the architecture of the fog and emerging IoT applications that will be improved by using the fog model. Finally, open issues and future research directions regarding fog computing and the IoT are discussed.
Soil Erosion as an Environmental Concern in Vineyards: The Case Study of Celler del Roure, Eastern Spain, by Means of Rainfall Simulation Experiments
Authors: Rodrigo-Comino Jesús , Keesstra Saskia , Cerdà Artemi
Published: April 2018

Soil erosion in vineyards is considered as an environmental concern as it depletes soil fertility and causes damage in the fields and downstream. High soil and water losses decrease soil quality, and subsequently, this can reduce the quality of the grapes and wine. However, in specialized journals of viticulture and enology, soil erosion studies are not present. This paper surveys the soil erosion losses in the vineyards of Celler del Roure, Eastern Spain, as an example of Mediterranean vineyards. We applied rainfall simulation experiments (10 plots) using a small portable rainfall simulator and 55 mm h−1 in one hour to characterize soil erodibility, runoff discharge, and soil erosion rates under low-frequency–high-magnitude rainfall events at different positions along the vine inter-row areas. We found that 30% of the rainfall was transformed into superficial runoff, the sediment concentration was 23 g L−1, and the soil erosion rates reached 4.1 Mg ha−1 h−1; these erosion rates are among the highest found in the existing literature. We suggest that the vineyard management should be improved to reduce land degradation, and also should be shifted to sustainable agricultural production, which could improve grape and wine quality.
Two Decades of “Horse Sweat” Taint and Brettanomyces Yeasts in Wine: Where do We Stand Now?
Authors: Malfeito-Ferreira Manuel
Published: April 2018

The unwanted modification of wine sensory attributes by yeasts of the species Brettanomyces bruxellensis due to the production of volatile phenols is presently the main microbiological threat to red wine quality. The effects of ethylphenols and other metabolites on wine flavor is now recognized worldwide and the object of lively debate. The focus of this review is to provide an update of the present knowledge and practice on the prevention of this problem in the wine industry. Brettanomyces bruxellensis, or its teleomorph, Dekkera bruxellensis, are rarely found in the natural environment and, although frequently isolated from fermenting substrates, their numbers are relatively low when compared with other fermenting species. Despite this rarity, they have long been studied for their unusual metabolical features (e.g., the Custers effect). Rising interest over the last decades is mostly due to volatile phenol production affecting high quality red wines worldwide. The challenges have been dealt with together by researchers and winemakers in an effective way and this has enabled a state where, presently, knowledge and prevention of the problem at the winery level is readily accessible. Today, the main issues have shifted from technological to sensory science concerning the effects of metabolites other than ethylphenols and the over estimation of the detrimental impact by ethylphenols on flavor. Hopefully, these questions will continue to be tackled together by science and industry for the benefit of wine enjoyment.
A 3D Microfluidic Model to Recapitulate Cancer Cell Migration and Invasion
Authors: Toh Yi-Chin , Raja Anju , Yu Hanry , Van Noort Danny
Published: April 2018

We have developed a microfluidic-based culture chip to simulate cancer cell migration and invasion across the basement membrane. In this microfluidic chip, a 3D microenvironment is engineered to culture metastatic breast cancer cells (MX1) in a 3D tumor model. A chemo-attractant was incorporated to stimulate motility across the membrane. We validated the usefulness of the chip by tracking the motilities of the cancer cells in the system, showing them to be migrating or invading (akin to metastasis). It is shown that our system can monitor cell migration in real time, as compare to Boyden chambers, for example. Thus, the chip will be of interest to the drug-screening community as it can potentially be used to monitor the behavior of cancer cell motility, and, therefore, metastasis, in the presence of anti-cancer drugs.
Study of Hydrogen Interactions with Nd2Fe17 and Nd2Fe14B by Means of Calorimetric Method
Authors: Anikina Elena , Verbetsky Victor , Savchenko Alexander
Published: April 2018

Hydrogen interactions with Nd2Fe17 and Nd2Fe14B was investigated by means of the calorimetric method with application of differential heat-conducting calorimeters that were of the Tean-Calvet type. The reaction of hydrogen absorption and desorption was carried out at 250 and 300 °C for Nd2Fe17, while the pressure-composition-isotherms (P-C-T) and enthalpy change with hydrogen concentration in the intermetallic compound (IMC) were obtained. The Nd2Fe14B-H2 system was studied at 50 °C and the dependence of the enthalpy change with hydrogen concentration in the intermetallic compound was also obtained. Based on the measured data, the assumption about the order of filling the interstitial sites by hydrogen atoms was made.
Failure Detection of Composites with Control System Corrective Response in Drone System Applications
Authors: Bowkett Mark , Thanapalan Kary , Constant Ewen
Published: April 2018

The paper describes a novel method for the detection of damage in carbon composites as used in drone frames. When damage is detected a further novel corrective response is initiated in the quadcopter flight controller to switch from a four-arm control system to a three-arm control system. This is made possible as a symmetrical frame is utilized, which allows for a balanced weight distribution between both the undamaged quadcopter and the fallback tri-copter layout. The resulting work allows for continued flight where this was not previously possible. Further developing work includes improved flight stability with the aid of an underslung load model. This is beneficial to the quadcopter as a damaged arm attached to the main body by the motor wires behaves as an underslung load. The underslung load works are also transferable in a dual master and slave drone system where the master drone transports a smaller slave drone by a tether, which acts as an underslung load.
Sigfox and LoRaWAN Datasets for Fingerprint Localization in Large Urban and Rural Areas
Authors: Aernouts Michiel , Berkvens Rafael , Van Vlaenderen Koen , Weyn Maarten
Published: April 2018

Because of the increasing relevance of the Internet of Things and location-based services, researchers are evaluating wireless positioning techniques, such as fingerprinting, on Low Power Wide Area Network (LPWAN) communication. In order to evaluate fingerprinting in large outdoor environments, extensive, time-consuming measurement campaigns need to be conducted to create useful datasets. This paper presents three LPWAN datasets which are collected in large-scale urban and rural areas. The goal is to provide the research community with a tool to evaluate fingerprinting algorithms in large outdoor environments. During a period of three months, numerous mobile devices periodically obtained location data via a GPS receiver which was transmitted via a Sigfox or LoRaWAN message. Together with network information, this location data is stored in the appropriate LPWAN dataset. The first results of our basic fingerprinting implementation, which is also clarified in this paper, indicate a mean location estimation error of 214.58 m for the rural Sigfox dataset, 688.97 m for the urban Sigfox dataset and 398.40 m for the urban LoRaWAN dataset. In the future, we will enlarge our current datasets and use them to evaluate and optimize our fingerprinting methods. Also, we intend to collect additional datasets for Sigfox, LoRaWAN and NB-IoT.
Development of Small UAS Beyond-Visual-Line-of-Sight (BVLOS) Flight Operations: System Requirements and Procedures
Authors: Fang Scott , O’Young Siu , Rolland Luc
Published: April 2018

Due to safety concerns of integrating small unmanned aircraft systems (UAS) into non-segregated airspace, aviation authorities have required a set of detect and avoid (DAA) systems to be equipped on small UAS for beyond-visual-line-of-sight (BVLOS) flight operations in civil airspace. However, the development of small UAS DAA systems also requires BVLOS flights for testing and validation. To mitigate operational risks for small UAS BVLOS flight operations, this paper proposes to initially test small UAS DAA systems in BVLOS flights in a restricted airspace with additional safety features. Later, this paper further discusses the operating procedures and emergency action plans for small UAS BVLOS flight operations. The testing results show that these safety systems developed can help improve operational safety for small UAS BVLOS flight operations.
Multichannel Signals Reconstruction Based on Tunable Q-Factor Wavelet Transform-Morphological Component Analysis and Sparse Bayesian Iteration for Rotating Machines
Authors: Li Qing , Hu Wei , Peng Erfei , Liang Steven
Published: April 2018

High-speed remote transmission and large-capacity data storage are difficult issues in signals acquisition of rotating machines condition monitoring. To address these concerns, a novel multichannel signals reconstruction approach based on tunable Q-factor wavelet transform-morphological component analysis (TQWT-MCA) and sparse Bayesian iteration algorithm combined with step-impulse dictionary is proposed under the frame of compressed sensing (CS). To begin with, to prevent the periodical impulses loss and effectively separate periodical impulses from the external noise and additive interference components, the TQWT-MCA method is introduced to divide the raw vibration signal into low-resonance component (LRC, i.e., periodical impulses) and high-resonance component (HRC), thus, the periodical impulses are preserved effectively. Then, according to the amplitude range of generated LRC, the step-impulse dictionary atom is designed to match the physical structure of periodical impulses. Furthermore, the periodical impulses and HRC are reconstructed by the sparse Bayesian iteration combined with step-impulse dictionary, respectively, finally, the final reconstructed raw signals are obtained by adding the LRC and HRC, meanwhile, the fidelity of the final reconstructed signals is tested by the envelop spectrum and error analysis, respectively. In this work, the proposed algorithm is applied to simulated signal and engineering multichannel signals of a gearbox with multiple faults. Experimental results demonstrate that the proposed approach significantly improves the reconstructive accuracy compared with the state-of-the-art methods such as non-convex Lq (q = 0.5) regularization, spatiotemporal sparse Bayesian learning (SSBL) and L1-norm, etc. Additionally, the processing time, i.e., speed of storage and transmission has increased dramatically, more importantly, the fault characteristics of the gearbox with multiple faults are detected and saved, i.e., the bearing outer race fault frequency at 170.7 Hz and its harmonics at 341.3 Hz, ball fault frequency at 7.344 Hz and its harmonics at 15.0 Hz, and the gear fault frequency at 23.36 Hz and its harmonics at 47.42 Hz are identified in the envelope spectrum.
Shaking up the Firm Survival: Evidence from Yogyakarta (Indonesia)
Authors: Brata Aloysius , De Groot Henri , Zant Wouter
Published: April 2018

The survival of firms under changes in the business environment caused by exogenous shocks can be explained using economic Darwinism. Exogenous shocks can cause ‘cleansing effects’. Shocks clean out unproductive firms so that available resources are allocated to the remaining more productive firms. However, shocks may also force out young firms that have the potential to be highly productive in the future, which will lower the average productivity of industries. This is known as the ‘scarring effect’ of shocks. Therefore, the overall impact of exogenous shocks on the allocation of resources depends on the relative magnitude of cleansing and scarring effects. This paper investigates this natural selection mechanism after the Yogyakarta earthquake in 2006. The study uses data on medium-sized and large manufacturing firms in the Yogyakarta province collected by the Indonesian Statistical Agency. The main finding of this paper is that firms that had higher productivity prior to the earthquake in 2006 were more likely to survive after the earthquake, which suggests the existence of a natural selection mechanism, specifically cleansing effects. There is no evidence of the scarring effects of the earthquake on the new entrants.
Senior Level Administrators and HBCUs: The Role of Support for Black Women’s Success in STEM
Authors: Washington Lockett Amanda , Gasman Marybeth , Nguyen Thai-Huy
Published: April 2018

While it is important for college and university senior administrators to embrace the traditional roles of their administrative positions, senior administrators’ interactions with students also shape institutional culture, students’ engagement, and ultimately play a role in students’ motivation to succeed. This engagement is especially evident in the Historically Black College and University (HBCU) context as senior administrators’ engagement with students can directly or indirectly affect how students perceive themselves and their ability to succeed. This article aims to illuminate the role that HBCU senior level administrators play in students’ motivation toward success. We also highlight the notion that senior level administrators’ role in organizational culture ultimately led historically-disempowered Black women students toward success in even the most historically inaccessible pathways in the science, technology, engineering, and math (STEM) fields. The study used semi-structured interviews with 71 Black women STEM students across 10 HBCUs and asked questions to better understand how events in their lives and on their campuses shaped their choice to pursue and persist through a STEM degree program. The study found that the women were highly motivated by their HBCUs’ family-like community of support. Integral to this article, this support was not confined to professors and peers, but extended to senior administrators. We conclude that Black women STEM students’ perception of their ability to succeed and their motivation is influenced by the institutions’ senior administration.
Energy Analysis at a Near Zero Energy Building. A Case-Study in Spain
Authors: Rey-Hernández Javier , Velasco-Gómez Eloy , San José-Alonso Julio , Tejero-González Ana , Rey-Martínez Francisco
Published: April 2018

This paper develops an energy analysis for an existing near Zero Energy (nZEB) and Zero Carbon Emissions building called LUCIA, located at the university campus in Valladolid (Spain). It is designed to supply electricity, cooling and heating needs through solar energy (Photovoltaic Systems, PV), biomass and an Earth–Air Heat Exchanger (EAHE), besides a Combined Heat Power (CHP). It is currently among the top three buildings with the highest LEED certification in the World. The building model is simulated with DesignBuilder version 5. The results of the energy analysis illustrate the heating, cooling and lighting consumptions expected, besides other demands and energy uses. From this data, we carried out an energy balance of the nZEB, which will help to plan preventive actions when compared to the actual energy consumptions, improving the management and control of both the building and its systems. The primary energy indicator obtained is 67 kWh/m2 a year, and 121 kWh/m2 a year for renewable energy generation, with respect to 55 kWh/m2 and 45 kWh/m2 set as reference in Europe. The Renewable Energy Ratio (RER) is 0.66. These indicators become a useful tool for the energy analysis of the nZEB according to the requirements in the European regulations and for its comparison with further nZEB.
Phase Change Material Selection for Thermal Energy Storage at High Temperature Range between 210 °C and 270 °C
Authors: Maldonado José , Fullana-Puig Margalida , Martín Marc , Solé Aran , Fernández Ángel , De Gracia Alvaro , Cabeza Luisa
Published: April 2018

The improvement of thermal energy storage systems implemented in solar technologies increases not only their performance but also their dispatchability and competitiveness in the energy market. Latent heat thermal energy storage systems are one of those storing methods. Therefore, the need of finding the best materials for each application becomes an appealing research subject. The main goal of this paper is to find suitable and economically viable materials able to work as phase change material (PCM) within the temperature range of 210–270 °C and endure daily loading and unloading processes in a system with Fresnel collector and an organic Rankine cycle (ORC). Twenty-six materials have been tested and characterized in terms of their thermophysical conditions, thermal and cycling stability, and health hazard. Two materials out of the 26 candidates achieved the last stage of the selection process. However, one of the two finalists would require an inert working atmosphere, which would highly increase the cost for the real scale application. This leads to a unique suitable material, solar salt (40 wt % KNO3/60 wt % NaNO3).
Impulsive Noise Characterization in Narrowband Power Line Communication
Authors: Bai Li , Tucci Mauro , Barmada Sami , Raugi Marco , Zheng Tao
Published: April 2018

Currently, narrowband Power line communication (PLC) is considered an attractive communication system in smart grid environments for applications such as advanced metering infrastructure (AMI). In this paper, we will present a comprehensive comparison and analysis in time and frequency domain of noise measured in China and Italy. In addition, impulsive noise in these two countries are mainly analyzed and modeled using two probability based models, Middleton Class A (MCA) model and α stable distribution model. The results prove that noise measured in China is rich in impulsive noise, and can be modeled well by α stable distribution model, while noise measured in Italy has less impulsive noise, and can be better modeled by the MCA model.
Flow-Through Pretreatment of Corn Stover by Recycling Organosolv to Reduce Waste Solvent
Authors: Park Yong , Kim Tae , Kim Jun
Published: April 2018

In this study, the optimum conditions for pretreatment of corn stover using organosolv were determined. The predicted optimum conditions, determined using the response surface methodology, were ethanol concentration of 56.6 wt %, reaction temperature of 187.5 °C, and 320 mL of liquid throughput. Moreover, the pretreatment using recycled organosolv was carried out under the predicted optimum conditions. The pretreatment effect of the organosolv decreased as the organosolv was reused in the pretreatment process. When performing pretreatment with the initial organosolv, enzymatic digestibility for glucan was 71.0%. The digestibility was reduced as low as less than 66% in the first reuse process. Nevertheless, when repeatedly reusing the organosolv, the glucan digestibility remained mostly stable. It was confirmed that organosolv can be reused in the flow-through pretreatment of corn stover.
Facile Synthesis of Highly Hydrophobic Cellulose Nanoparticles through Post-Esterification Microfluidization
Authors: Lin Chunxiang , Ma Qianli , Su Qiaoquan , Bian Huiyang , Zhu J.
Published: April 2018

A post-esterification with a high degree of substitution (hDS) mechanical treatment (Pe(hDS)M) approach was used for the production of highly hydrophobic cellulose nanoparticles (CNPs). The process has the advantages of substantially reducing the mechanical energy input for the production of CNPs and avoiding CNP aggregation through drying or solvent exchange. A conventional esterification reaction was carried out using a mixture of acetic anhydride, acetic acid, and concentrated sulfuric acid, but at temperatures of 60–85 °C. The successful hDS esterification of bleached eucalyptus kraft pulp fibers was confirmed by a variety of techniques, such as Fourier transform infrared (FTIR), solid state 13C NMR, X-ray photoelectron spectroscopy (XPS), elemental analyses, and X-ray diffraction (XRD). The CNP morphology and size were examined by atomic force microscopy (AFM) as well as dynamic light scattering. The hydrophobicity of the PeM-CNP was confirmed by the redispersion of freeze-dried CNPs into organic solvents and water contact-angle measurements. Finally, the partial conversion of cellulose I to cellulose II through esterification improved PeM-CNP thermal stability.
The Relation between the Rheological Properties of Gels and the Mechanical Properties of Their Corresponding Aerogels
Authors: Sun Mingze , Sun Hua , Wang Yutao , Sánchez-Soto Miguel , Schiraldi David
Published: April 2018

A series of low density, highly porous clay/poly(vinyl alcohol) composite aerogels, incorporating ammonium alginate, were fabricated via a convenient and eco-friendly freeze drying method. It is significant to understand rheological properties of precursor gels because they directly affect the form of aerogels and their processing behaviors. The introduction of ammonium alginate impacted the rheological properties of colloidal gels and improved the mechanical performance of the subject aerogels. The specific compositions and processing conditions applied to those colloidal gel systems brought about different aerogel morphologies, which in turn translated into the observed mechanical properties. The bridge between gel rheologies and aerogel structures are established in the present work.
Squamous Cell Carcinoma Antigen 2 (SCCA2, SERPINB4): An Emerging Biomarker for Skin Inflammatory Diseases
Authors: Izuhara Kenji , Yamaguchi Yukie , Ohta Shoichiro , Nunomura Satoshi , Nanri Yasuhiro , Azuma Yoshinori , Nomura Noriko , Noguchi Yasuhiko , Aihara Michiko
Published: April 2018

Squamous cell carcinoma antigens 1 and 2 (SCCA1 and 2, SERPIN B3 and B4), members of the ovalbumin serpin (ov-serpin)/clade B serpin family, were originally discovered as tumor-specific antigens and are used as tumor markers for various kinds of squamous cell carcinomas. Recently, our understanding of the underlying mechanisms of how SCCA1/2 enhance tumor growth has greatly increased. Moreover, it has been shown that SCCA1/2 are involved in the pathogenesis of several inflammatory diseases: asthma, psoriasis, and atopic dermatitis (AD). IL-22 and IL-17, signature cytokines of type 17 inflammation, as well as IL-4 and IL-13, signature cytokines of type 2 inflammation, both of which are positively correlated with the pathogenesis of psoriasis and allergic diseases, respectively, can induce expression of SCCA1/2 in airway epithelial cells and/or keratinocytes, leading to high expression of SCCA1/2 in these diseases. Based on these findings, several trials have been performed to examine the potential of applying SCCA1/2 to biomarkers for these diseases. The findings show that SCCA2 is useful to aid diagnosis, estimate clinical severity and disease type, and assess responses to treatment in psoriasis and AD. These results suggest that SCCA2 has emerged as a novel biomarker for skin inflammatory diseases.
Global and Complement Gene-Specific DNA Methylation in Grass Carp after Grass Carp Reovirus (GCRV) Infection
Authors: Xiong Lv , He Libo , Luo Lifei , Li Yongming , Liao Lanjie , Huang Rong , Zhu Zuoyan , Wang Yaping
Published: April 2018

Grass carp reovirus (GCRV) causes huge economic loss to the grass carp cultivation industry but the mechanism remains largely unknown. In this study, we investigated the global and complement gene-specific DNA methylation in grass carp after GCRV infection aimed to uncover the mechanism underlying GCRV infection. The global DNA methylation level was increased after GCRV infection. Expression levels of enzymes involved in DNA methylation including DNA methyltransferase (DNMT), ten-eleven translocation proteins (TETs), and glycine N-methyltransferase (GNMT) were significantly altered after GCRV infection. In order to investigate the relationship between the gene expression level and DNA methylation level, two representative complement genes, complement component 3 (C3) and kininogen-1 (KNG1), were selected for further analysis. mRNA expression levels of the two genes were significantly increased at 5 and 7 days after GCRV infection, whereas the DNA methylation level at the 5′ flanking regions of the two genes were down-regulated at the same time-points. Moreover, a negative correlation was detected between gene expression levels and DNA methylation levels of the two genes. Therefore, the current data revealed a global and complement gene-specific DNA methylation profile after GCRV infection. Our study would provide new insights into understanding the mechanism underlying GCRV infection.
Differential Expression and Clinical Significance of Transforming Growth Factor-Beta Isoforms in GBM Tumors
Authors: Roy Laurent-Olivier , Poirier Marie-Belle , Fortin David
Published: April 2018

Glioblastoma (GBM) represents the most common and aggressive malignant primary brain tumors in adults. Response to standard treatment is transitory and the survival of clinical trial cohorts are little more than 14 months. GBM are characterized by excessive proliferation, invasiveness, and radio-/chemoresistance features; which are strongly upregulated by transforming growth factor-beta (TGF-β). We hypothesized that TGF-β gene expression could correlate with overall survival (OS) and serve as a prognostic biomarker. TGF-β1 and -β2 expression were analyzed by qPCR in 159 GBM tumor specimens. Kaplan–Meier and multivariate analyses were used to correlate expression with OS and progression-free survival (PFS). In GBM, TGF-β1 and -β2 levels were 33- and 11-fold higher respectively than in non-tumoral samples. Kaplan–Meier and multivariate analyses revealed that high to moderate expressions of TGF-β1 significantly conferred a strikingly poorer OS and PFS in newly diagnosed patients. Interestingly, at relapse, neither isoforms had meaningful impact on clinical evolution. We demonstrate that TGF-β1 is the dominant isoform in newly diagnosed GBM rather than the previously acknowledged TGF-β2. We believe our study is the first to unveil a significant relationship between TGF-β1 expression and OS or PFS in newly diagnosed GBM. TGF-β1 could serve as a prognostic biomarker or target affecting treatment planning and patient follow-up.
BMP9 Promotes the Proliferation and Migration of Bladder Cancer Cells through Up-Regulating lncRNA UCA1
Authors: Gou Liyao , Liu Mengyao , Xia Jing , Wan Qun , Jiang Yayun , Sun Shilei , Tang Min , Zhou Lan , He Tongchuan , Zhang Yan
Published: April 2018

As the most common malignant tumor of the urinary system worldwide, the bladder tumor has a high mortality rate, which is mainly due to its onset of concealment. Therefore, research into novel diagnostic markers and treatment of bladder cancer is urgently needed. BMP9 (Bone morphogenetic protein 9) is a member of BMP, which belongs to the TGF-β (transforming growth factor-β) superfamily. It has been associated with multiple tumors. We found that BMP9 is highly expressed in bladder cancer cells and it could significantly promote the proliferation and migration of bladder cancer cells. In the study of the mechanism of this effect, we found that BMP9 can increase the expression of lncRNA UCA1 (Urothelial cancer associated 1) through phosphorylated AKT. The promoting effect of BMP9 on bladder cancer cells was rescued after interfering with UCA1 in BMP9 overexpressed bladder cancer cells both in vitro and in vivo. Our research confirms that BMP9 promotes the proliferation and migration of bladder cancer cells through up-regulated lncRNA UCA1. It also shows that BMP9 is a novel diagnostic marker and a potential therapeutic target in bladder cancer.
Prospects of Understanding the Molecular Biology of Disease Resistance in Rice
Authors: Singh Pankaj , Nag Akshay , Arya Preeti , Kapoor Ritu , Singh Akshay , Jaswal Rajdeep , Sharma Tilak
Published: April 2018

Rice is one of the important crops grown worldwide and is considered as an important crop for global food security. Rice is being affected by various fungal, bacterial and viral diseases resulting in huge yield losses every year. Deployment of resistance genes in various crops is one of the important methods of disease management. However, identification, cloning and characterization of disease resistance genes is a very tedious effort. To increase the life span of resistant cultivars, it is important to understand the molecular basis of plant host–pathogen interaction. With the advancement in rice genetics and genomics, several rice varieties resistant to fungal, bacterial and viral pathogens have been developed. However, resistance response of these varieties break down very frequently because of the emergence of more virulent races of the pathogen in nature. To increase the durability of resistance genes under field conditions, understanding the mechanismof resistance response and its molecular basis should be well understood. Some emerging concepts like interspecies transfer of pattern recognition receptors (PRRs) and transgenerational plant immunitycan be employed to develop sustainable broad spectrum resistant varieties of rice.
Effects of Introducing Methoxy Groups into the Ancillary Ligands in Bis(diimine) Copper(I) Dyes for Dye-Sensitized Solar Cells
Authors: Büttner Annika , Brauchli Sven , Constable Edwin , Housecroft Catherine
Published: April 2018

A systematic investigation of four heteroleptic bis(diimine) copper(I) dyes in n-type Dye-Sensitized Solar Cells (DSSCs) is presented. The dyes are assembled using a stepwise, on-surface assembly. The dyes contain a phosphonic acid-functionalized 2,2′-bipyridine (bpy) anchoring domain (5) and ancillary bpy ligands that bear peripheral phenyl (1), 4-methoxyphenyl (2), 3,5-dimethoxyphenyl (3), or 3,4,5-trimethoxyphenyl (4) substituents. In masked DSSCs, the best overall photoconversion efficiency was obtained with the dye [Cu(5)(4)]+ (1.96% versus 5.79% for N719). Values of JSC for both [Cu(5)(2)]+ (in which the 4-MeO group is electron releasing) and [Cu(5)(4)]+ (which combines electron-releasing and electron-withdrawing effects of the 4- and 3,5-substituents) and are enhanced with respect to [Cu(5)(1)]+. DSSCs with [Cu(5)(3)]+ show the lowest JSC. Solid-state absorption spectra and external quantum efficiency spectra reveal that [Cu(5)(4)]+ benefits from an extended spectral range at higher energies. Values of VOC are in the order [Cu(5)(4)]+ > [Cu(5)(1)]+ > [Cu(5)(2)]+ > [Cu(5)(3)]+. Density functional theory calculations suggest that methoxyphenyl character in MOs within the HOMO manifold in [Cu(5)(2)]+ and [Cu(5)(4)]+ may contribute to the enhanced performances of these dyes with respect to [Cu(5)(1)]+.
Differential Diagnosis of Autism Spectrum Disorder and Post Traumatic Stress Disorder: Two Clinical Cases
Authors: Stavropoulos Katherine , Bolourian Yasamine , Blacher Jan
Published: April 2018

Autism spectrum disorder (ASD) is estimated to affect one in 68 children. Given the increase in both prevalence and awareness of ASD, it is critical to provide accurate and timely diagnosis. However, ASD often co-occurs with other disorders, making diagnosis difficult. The objective of the current case study was to provide two examples of differential diagnosis in ASD and post-traumatic stress disorder (PTSD) observed in an autism clinic. In both cases, the goal was to decide whether each child should be given a diagnosis of ASD, PTSD, or both.
Asymptomatic Effect of Occupational Radiation Exposure on Thyroid Gland Hormones and Thyroid Gland Ultrasonographic Abnormalities
Authors: Alawneh Khaled , Alshehabat Musa , Al-Ewaidat Haytham , Raffee Liqaa , Forihat Duaa , Khader Yousef
Published: April 2018

Data evaluating the effect of asymptomatic effects of radiation on thyroid hormone panels and ultrasonographic abnormalities among radiology technologists are scarce. This study aimed to determine the asymptomatic effect of radiation in a total of 39 male and 11 female exposed radiology technologists working in radiology departments, and a total of 34 male and 16 female age-matched controls working in other departments in the same hospital. The level of triiodothyronine (T3), thyroxine (T4) and thyroid-stimulating hormone (TSH) were evaluated using Enzyme Linked Immunosorbent Assay (ELISA). Thyroid ultrasonographic evaluation outcomes were given as normal or abnormal. There was significant interaction between exposure and gender in the mean TSH and T4 but not T3. The mean TSH for exposed men was significantly higher than that among non-exposed men (2.28 mIU/L vs. 1.59 mIU/L; p-value = 0.003). The mean TSH was not significantly different between exposed and non-exposed women. The mean T4 for exposed men was significantly higher when compared with non-exposed men (11.1 pmol/L vs. 10.05 pmol/L; p-value = 0.005). In the non-exposed group, 93.8% of women and 94.1% of men had T4 values lower than established normal reference range, while in the exposed group, 90.9% of women and 74.4% of men had low values of T4. There was no significant difference in mean T3 between exposed and non-exposed groups for men and women. Furthermore, there were no significant differences in the thyroid gland ultrasonographic findings between exposed and non-exposed groups. Occupational radiation exposure is associated with increased means of TSH and T3, especially among men.
Enhanced Efficacy of High Dose Oral Vancomycin Therapy in Clostridium difficile Diarrhea for Hospitalized Adults Not Responsive to Conventional Oral Vancomycin Therapy: Antibiotic Stewardship Implications
Authors: Cunha Burke , Sessa Julia , Blum Sharon
Published: April 2018

Current therapy of Clostridium difficile diarrhea (CDD) is problematic. Optimal treatment for CDD remains oral vancomycin, but there is little data on oral vancomycin dosing regimens. The objective of this C. difficile diarrhea study was to compare the efficacy of “high dose” vancomycin, 500 mg (PO) q6h, as sole treatment and in those who after 72 h failed to respond to conventional doses of oral vancomycin, 125–250 mg (PO) q6h. Hospitalized adults with CDD were evaluated by various oral vancomycin regimens, i.e., a conventional dose group (125–250 mg (PO) q6h), a “high dose escalation” dose group (250 mg → 500 mg (PO) q6h), and a “high dose” group (500 mg (PO) q6h). Oral vancomycin treatment groups were compared by time to improvement, i.e., decrease in >50% of watery stools/day and duration of therapy. The high dose escalation and high dose oral vancomycin groups showed the most rapid resolution of diarrhea. There was marked decrease in stools/day after “high dose” vancomycin escalation from conventional dosing, i.e., 250 mg (PO) q6h → 500 mg (PO) q6h. This study demonstrated that “high dose” escalation or initial high dose oral vancomycin, i.e., 500 mg (PO) q6h was the most efficacious regimen for CDD.
Mucormycosis: Battle with the Deadly Enemy over a Five-Year Period in India
Authors: Chander Jagdish , Kaur Mandeep , Singla Nidhi , Punia R. , Singhal Surinder , Attri Ashok , Alastruey-Izquierdo Ana , Stchigel Alberto , Cano-Lira Jose , Guarro Josep
Published: April 2018

Mucormycosis is an emerging opportunistic fungal infection. Increasing immunocompromization, widespread use of antibacterial and antifungal agents (such as voriconazole prophylaxis), carcinomas, transplantation and lifestyle diseases such as diabetes are the main contributors to this situation. The predominant clinical manifestations of mucormycosis vary from host to host, with rhino-orbital-cerebral, pulmonary, cutaneous, and gastrointestinal infections being the most common. In India, the prevalence of mucormycosis is approximately 0.14 cases/1000 population, which is about 70 times the worldwide-estimated rate for mucormycosis. The present study was undertaken over a period of five years (January 2009–December 2014) to determine the prevalence of mucormycosis. The samples suspected of mucormycosis were examined by direct KOH wet mount and cultured on Sabouraud’s dextrose agar without actidione and on blood agar as per standard mycological techniques. Histopathological correlation was done for most of the cases. Antifungal susceptibility testing was performed by the EUCAST reference method. We identified a total of 82 cases of mucormycosis out of a total of 6365 samples received for mycological culture and examination during the said time period. Out of these, 56 were male patients and 27 were females. Most common presentation was rhino-orbito-cerebral (37), followed by cutaneous (25), pulmonary (14), oral cavity involvement (4) and gastrointestinal (2). The most common risk factors were diabetes and intramuscular injections. The fungi isolated were Rhizopus arrhizus (17), Apophysomyces variabilis (12), R. microsporus (9), Lichtheimia ramosa (8), Saksenaea erythrospora (5), Syncephalastrum racemosus (4), R. homothallicus (2), Rhizomucor pusillus (1), Mucor irregularis (1) and A. elegans (1). The mainstay of the treatment was amphotericin B, along with extensive surgical debridement whenever feasible. Most of the patients (50) recovered, but 25 died. The rest of the patients left against medical advice. “Nip in the Bud” should be the mantra for clinicians/surgeons for a favorable prognosis. Early diagnosis, prompt institution of appropriate antifungal therapy, surgical debridement whenever necessary, knowledge of risk factors and their timely reversal is the key for management.