bluuebunny/crossref_metadata_2025 huggingface dataset:
Energy Harvesting for Physical Layer Security in Cooperative Networks Based on Compressed Sensing
Authors: Chang Shuai , Li Jialun , Fu Xiaomei , Zhang Liang
Published: September 2017

Energy harvesting (EH) has attracted a lot of attention in cooperative communication networks studies for its capability of transferring energy from sources to relays. In this paper, we study the secrecy capacity of a cooperative compressed sensing amplify and forward (CCS-AF) wireless network in the presence of eavesdroppers based on an energy harvesting protocol. In this model, the source nodes send their information to the relays simultaneously, and then the relays perform EH from the received radio-frequency signals based on the power splitting-based relaying (PSR) protocol. The energy harvested by the relays will be used to amplify and forward the received information to the destination. The impacts of some key parameters, such as the power splitting ratio, energy conversion efficiency, relay location, and the number of relays, on the system secrecy capacity are analyzed through a group of experiments. Simulation results reveal that under certain conditions, the proposed EH relaying scheme can achieve higher secrecy capacity than traditional relaying strategies while consuming equal or even less power.
A Hybrid Approach for Power System Security Enhancement via Optimal Installation of Flexible AC Transmission System (FACTS) Devices
Authors: Kang Tong , Yao Jiangang , Duong ThanhLong , Yang Shengjie , Zhu Xiangqian
Published: September 2017

Increasing demand for electricity has placed heavy stress on power system security. Therefore, this paper focuses on the problem of how to maximize power system static security in terms of branch loading and voltage level under normal operation and even the most critical single line contingency conditions. This paper proposes a hybrid approach to find out the optimal locations and settings of two classical types of flexible AC transmission system (FACTS) devices, namely thyristor-controlled series compensators (TCSCs) and static var compensators (SVCs) for solving this problem. Our proposed approach requires a two-step strategy. Firstly, the min cut algorithm (MCA) and tangent vector technique (TVT) are applied to determine the proper candidate locations of TCSC and SVC respectively so as to reduce the search scope for a solution to the problem, and then the cuckoo search algorithm (CSA) is employed to solve this problem by simultaneously optimizing the locations and settings for TCSC and SVC installation. The proposed hybrid approach has been verified on the IEEE 6-bus and modified IEEE 14-bus test systems. The results indicate that CSA outperforms particle swarm optimization (PSO), proving its effectiveness and potential, and they also show that our proposed hybrid approach can find the best locations and settings for TCSC and SVC devices as an effective way for enhancing power system static security by removing or alleviating the overloads and voltage violations under normal operation and even the most critical single line contingency conditions. Using this hybrid approach, the search space for solution to the problem becomes limited hence the computational burden will be decreased.
Cost Analysis for a Hybrid Advanced Metering Infrastructure in Korea
Authors: Park Sung-Won , Son Sung-Yong
Published: September 2017

Advanced metering infrastructure (AMI) refers to the electricity service infrastructure between electricity consumers and suppliers and is technically essential for the realization of a smart grid environment. To implement AMI, various communications technologies are being used based on the application environment according to the utility. However, using a single communications method can give rise to attenuation in the downtown underground distribution line section or cause higher supply costs due to decreased density in the range from farming to fishing areas. A hybrid AMI is one solution to this problem. According to an economic analysis of previous AMI deployment, the cost to install a communications network accounts on average for 45% of the total cost. Since the installation cost of a communications network is influenced by the density of the installation environment, a hybrid AMI, which allows the configuration of a flexible network using both wired and wireless communications, can be a good alternative, both technically and financially. This study conducted a simulation based on density of the installation environment and configuration of the communications network to analyze the economic effect of installing a hybrid AMI communications network. It assumed that a hybrid AMI was deployed in an overhead distribution line in a low-density area. The simulation outcomes were compared and analyzed against the power line communication (PLC)-only AMI method. The results showed that the hybrid AMI method had a 10% communications network cost reduction effect compared to the PLC-only AMI method. In addition, the analysis indicated that there was a maximum 19% cost reduction effect in communications network installation depending on the method of network installation, suggesting that the hybrid AMI was economically more effective than the PLC-only AMI method.
Investigation of Hydraulic-Mechanical Properties of Paste Backfill Containing Coal Gangue-Fly Ash and Its Application in an Underground Coal Mine
Authors: Zhang Xinguo , Lin Jia , Liu Jinxiao , Li Fei , Pang Zhenzhong
Published: September 2017

Backfilling is widely used to control surface subsidence and stope stability to improve pillar recovery. Furthermore, it is also an effective way to process and dispose of mining waste such as coal gangue and tailings. In this study, the hydraulic-mechanical properties of cemented paste backfill materials (CPB) were investigated. Twenty-eight cemented coal gangue-fly ash backfill mixtures were prepared with different water, cement, fly ash and coal gangue content and the slump, segregation and water bleeding ratio tests were conducted. Increasing fly ash content increased the slump value and decreased the segregation value of the slurry. The uniaxial compressive strength (UCS) of the cemented coal gangue-fly ash backfill samples were tested at different curing times. Based on the test results, an optimized recipe was used for the field trial. Longwall cut and backfilling mining method was used in the 2300 mining district to recycle the coal pillar between longwall 2301 and 2302. Both stress and displacement meters were installed in the goaf and their performance was monitored continuously. An increase in stress and displacement values were observed to occur with the working face advanced (up to 325 m and 375 m, respectively); thereafter, a trend of stabilization was observed. The monitoring results suggest that the backfills can efficiently control the roof movement and surface subsidence as well as improve pillar recovery.
Ethyl Methyl Sulfone-Based Electrolytes for Lithium Ion Battery Applications
Authors: Hilbig Peter , Ibing Lukas , Wagner Ralf , Winter Martin , Cekic-Laskovic Isidora
Published: September 2017

Sulfone-based electrolytes, known for their higher oxidative stability compared to the typically used organic carbonate-based electrolytes, are considered promising electrolytes for high voltage cathode materials towards the objective of obtaining increased energy density in lithium ion batteries. Nevertheless, sulfones suffer from high viscosity as well as incompatibility with highly graphitic anode materials, which limit their application. In this paper, the effect of fluoroethylene carbonate (FEC) as an electrolyte additive for the application of ethyl methyl sulfone (EMS) electrolytes containing LiPF6 as conducting salt, is studied in graphite-based cells by means of selected electrochemical and spectroscopic methods. In addition, influence of ethylene acetate (EA) as co-solvent on the electrolyte viscosity and conductivity of the EMS-based electrolytes is discussed, revealing improved overall nickel cobalt manganese oxide (NMC)/graphite cell performance. X-ray photoelectron spectroscopy (XPS) measurements provide information about the surface chemistry of the graphite electrodes after galvanostatic cycling. The concept of EA as co-solvent is found to be applicable for other sulfones such as isopropyl methyl sulfone (MeiPrSO2) and ethyl isopropyl sulfone (EtiPrSO2).
Maximum Power Point Tracking of Photovoltaic Panels by Using Improved Pattern Search Methods
Authors: Tobón Andrés , Peláez-Restrepo Julián , Villegas-Ceballos Juan , Serna-Garcés Sergio , Herrera Jorge , Ibeas Asier
Published: September 2017

This paper deals with the optimization of maximum power point tracking when a photovoltaic panel is modelled as two diodes. The adopted control is implemented using a sliding mode control (SMC) and the optimization is implemented using an improved Pattern Search Method. Thus, the problem of maximum power point tracking is reduced to an optimization problem whose solution is implemented by Pattern Search Techniques, inheriting their convergence properties. Simulation examples show the effectiveness of the proposed technique in practice, being able to deal with different radiations. In addition, improved pattern search method (IPSM) is compared with other techniques such as perturb & observe and Particle Swarm optimization, after which IPSM presents lower energy losses in comparison with the other two algorithms, with the advantage of ensuring the location of the optimal power point in all cases.
An Energy-Efficient Coverage Algorithm for Macrocell—Small Cell Network Systems
Authors: Chung Yao-Liang
Published: September 2017

The energy efficiency of a macrocell base station (MBS) can be substantially improved via the deployment of small cell base stations (SBSs) within the coverage area of the MBS. Moreover, this approach is expected to remain a key feature of communication network markets in the future. However, little research has been conducted to uncover effective solutions to the issue of coverage holes (i.e., specific locations or areas in which a user is not able to get an adequate signal from the wireless network) that may occur in the context of such a network architecture. To address this dearth of relevant research, the present study proposes an energy-efficient coverage algorithm utilizing novel system configurations, for use in such macrocell—small cell network systems. The goal of the proposed algorithm is providing the maximum possible reduction of the combined power consumed by the transceivers of all the BSs (that is, the SBSs and the MBS), while simultaneously guaranteeing the provision of comprehensive wireless signal coverage to users under various scenarios. In order to accomplish this aim in an efficient manner, the algorithm smartly adjusts the power levels of all the SBSs in a given system, including the full deactivation of a previously active SBS, or the activation of a previously inactive SBS, according to the dynamics of the given network traffic, thereby modifying their power consumption as necessary. The results for simulations of various test scenarios indicated that the algorithm exhibits better performance than two conventional methods in terms of its overall effects on coverage, power usage, and average transmission rate. The simulated power savings yielded by the proposed algorithm were particularly notable, as it garnered an improvement as high as 78% under the condition of light traffic volumes.
Green Carbon Composite-Derived Polymer Resin and Waste Cotton Fibers for the Removal of Alizarin Red S Dye
Authors: Wanassi Béchir , Hariz Ichrak Ben , Ghimbeu Camélia Matei , Vaulot Cyril , Jeguirim Mejdi
Published: September 2017

Phenolic resin and waste cotton fiber were investigated as green precursors for the successful synthesis using a soft template approach of a composite carbon with carbon nanofibers embedded in a porous carbon network with ordered and periodically pore structure. The optimal composite carbon (PhR/NC-1), exhibited a specific surface area of 394 m2∙g−1 with the existence of both microporosity and mesoporosity. PhR/NC-1 carbon was evaluated as an adsorbent of Alizarin Red S (ARS) dye in batch solution. Various operating conditions were examined and the maximum adsorption capacity of 104 mg∙g−1 was achieved under the following conditions, i.e., T = 25 °C, pH = 3, contact time = 1440 min. The adsorption and desorption heat was assessed by flow micro-calorimetry (FMC), and the presence of both exothermic and endothermic peaks with different intensity was evidenced, meaning a partially reversible nature of ARS adsorption. A pseudo-second-order model proved to be the most suitable kinetic model to describe the ARS adsorption according to the linear regression factor. In addition, the best isotherm equilibrium has been achieved with a Freundlich model. The results show that the eco-friendly composite carbon derived from green phenolic resin mixed with waste cotton fibers improves the removal of ARS dye from textile effluents.
Development of Northern White-Cedar (Thuja occidentalis L.) Plantations within and outside Deer Yards
Authors: Villemaire-Côté Olivier , Ruel Jean-Claude , Sirois Luc
Published: September 2017

Regional surveys done over the last decades show a clear decline in abundance of Northern white-cedar (Thuja occidentalis L.) throughout its range. A lack of seed trees, difficulties in the establishment of natural regeneration and high browsing pressure caused by increasing deer populations have been identified as plausible causes. Current silvicultural strategies for cedar restoration recommend partial cutting to promote and release natural regeneration, but there is also a need to restore the species in areas where it became absent. Yet, little attention has been given to cedar plantations. This study provides a first characterisation of the effects of competition, silvicultural treatments and deer, moose and hare browsing on planted cedar growth, survival, and stem form. Pure and mixed cedar plantations aged 5–27 years located in Eastern Québec were sampled. Both inside and outside deer yards, planted cedars showed high survival rates and were generally subject to low browsing pressure, but 45% were forked. Cedars showed high growth rates and strong reaction to stand opening. Results suggest that at reduced competition levels, a 9-year browser exclusion could be sufficient to establish safe-from-browsing cedar stands of >3 m in height.
The Outer Halos of Very Massive Galaxies: BCGs and their DSC in the Magneticum Simulations
Authors: Remus Rhea-Silvia , Dolag Klaus , Hoffmann Tadziu
Published: September 2017

Recent hydrodynamic cosmological simulations cover volumes up to Gpc 3 and resolve halos across a wide range of masses and environments, from massive galaxy clusters down to normal galaxies, while following a large variety of physical processes (star-formation, chemical enrichment, AGN feedback) to allow a self-consistent comparison to observations at multiple wavelengths. Using the Magneticum simulations, we investigate the buildup of the diffuse stellar component (DSC) around massive galaxies within group and cluster environments. The DSC in our simulations reproduces the spatial distribution of the observed intracluster light (ICL) as well as its kinematic properties remarkably well. For galaxy clusters and groups we find that, although the DSC in almost all cases shows a clear separation from the brightest cluster galaxy (BCG) with regard to its dynamic state, the radial stellar density distribution in many halos is often characterized by a single Sérsic profile, representing both the BCG component and the DSC, very much in agreement with current observational results. Interestingly, even in those halos that clearly show two components in both the dynamics and the spatial distribution of the stellar component, no correlation between them is evident.
3D Microstructure Inhibits Mesenchymal Stem Cells Homing to the Site of Liver Cancer Cells on a Microchip
Authors: Yang Xingyuan , Xu Xinyue , Zhang Yuan , Wen Weijia , Gao Xinghua
Published: September 2017

The cell microenvironment consists of multiple types of biophysical and biochemical factors, and represents a complex integrated system that is variable in both time and space. Studies show that changes in biochemical and biophysical factors in cell microenvironments result in significant changes in cellular forms and functions, especially for stem cells. Mesenchymal stem cells (MSCs) are derived from adult stem cells of the mesoderm and play an important role in tissue engineering, regenerative medicine and even cancer therapy. Furthermore, it is found that MSCs can interact with multiple types of tumor cells. The interaction is reflected as two totally different aspects. The negative aspect is that MSCs manifest as tumor-associated fibroblasts and could induce migration of cancer cells and promote tumor formation. On the other hand, MSCs can home to sites of the tumor microenvironment, directionally migrate toward tumor cells and cause tumor cell apoptosis. In this study, we designed and made a simple microfluidic chip for cell co-culture, and studied stem cell homing behavior in the interaction between MSCs and liver cancer cells. Moreover, by etching a three-dimensional microstructure on the base and adding transforming growth factor-β (TGF-β) in the co-culture environment, we studied the impact of biophysical and biochemical factors on stem cell homing behavior, and the causes of such impact.
Comparison of the Mineral Element Content of Public Drinking Fountains and Bottled Water: A Case Study of Ferrara City
Authors: Di Giuseppe Dario
Published: September 2017

Mineral elements are essential nutrients for humans and play important roles in many human physiological and bio-chemical processes. In this study, a comparison between the levels of mineral elements present in the water of public drinking fountains (PDRF) and in bottled water was carried out. The aim of the study is to assess the effectiveness of PDRF as a mineral supplement, compared to the low-mineral bottled water for out-door non-competitive activity, such as jogging. The city of Ferrara was chosen as the study site. It has ancient walls and on their top there is a gravel road that people use for jogging and walking. Along the road, there are two public drinking fountains that are always used. Water from these fountains was sampled and analysed for major cations and anions using ionic chromatography. Data analyses were compared with the same analyses carried out on bottled water usually used by joggers. Results showed that fountains are a valid substitute of bottled water as they have a moderate content of mineral elements. During outdoor sport activity, the water from fountains is preferable for the reintegration of mineral elements, instead of bottled water that has a very low quantity of minerals.
Change of Title: Microarrays Becomes High-Throughput
Authors: Negrini Massimo
Published: September 2017

MDPI’s journal Microarrays released its first volume in 2012. Since then, the journal has published 129 articles on the topic of microarrays, including their applications, analysis and new developments. [...]
Oral Health: The Need for Both Conventional Microbial and Molecular Characterization
Authors: Friedman Elisheva , Alizadeh Negin , Loewy Zvi
Published: September 2017

This study aims to consider the microbial distribution in oral disease, as well as gene analysis and expression, in elucidating: 1, the fundamental underpinnings of oral disease, and 2, the potential relationship between oral diseases and systemic health. A key focus is identifying the microbiota associated with oral disease manifestations characterized by both conventional microbiological and molecular methods. Variations in the observed microbial populations characterized by conventional and molecular approaches have been identified for caries, periodontitis, peri-implantitis, and stomatitis. The discovery of therapeutic approaches for oral disease will require comprehensive microbial and genomic analysis. This study evaluated the current state of the relevant microbial and genomic information for several prevalent oral diseases.
High‐Throughput Methods to Detect Long Non‐Coding RNAs
Authors: Uchida Shizuka
Published: September 2017

Increasing evidence suggests that the numbers of long non‐coding RNAs (lncRNAs) are more than those of protein‐coding genes in various organisms. Although the detection methods for lncRNAs are being increasingly established, there are advantages and disadvantages that exist for each method. In this opinion article, I highlight the differences between microarrays and RNA sequencing (RNA‐seq) for the detection of lncRNAs. Compared to RNA‐seq, microarrays are limited to the known sequences. However, the detection method as well as data analysis workflow is more established, which makes it easier to analyze the data for bench scientists without extensive knowledge about computer programming. In order to highlight the usage of microarrays over RNA‐seq for the detection of lncRNAs, we are organizing a special issue for High‐Throughput called “Microarrays in Non‐Coding RNAs Profiling”, which will include the specific usages of microarrays for lncRNAs.
Identification of a Group’s Physiological Synchronization with Earth’s Magnetic Field
Authors: Timofejeva Inga , McCraty Rollin , Atkinson Mike , Joffe Roza , Vainoras Alfonsas , Alabdulgader Abdullah , Ragulskis Minvydas
Published: September 2017

A new analysis technique for the evaluation of the degree of synchronization between the physiological state of a group of people and changes in the Earth’s magnetic field based on their cardiac inter-beat intervals was developed and validated. The new analysis method was then used to identify clusters of similar synchronization patterns in a group of 20 individuals over a two-week period. The algorithm for the identification of slow wave dynamics for every person was constructed in order to determine meaningful interrelationships between the participants and the local magnetic field data. The results support the hypothesis that the slow wave rhythms in heart rate variability can synchronize with changes in local magnetic field data, and that the degree of synchronization is affected by the quality of interpersonal relationships.
Antimicrobial Susceptibility of Staphylococcus aureus Isolated from Recreational Waters and Beach Sand in Eastern Cape Province of South Africa
Authors: Akanbi Olufemi Emmanuel , Njom Henry Akum , Fri Justine , Otigbu Anthony C. , Clarke Anna M.
Published: September 2017

Background: Resistance of Staphylococcus aureus to commonly used antibiotics is linked to their ability to acquire and disseminate antimicrobial-resistant determinants in nature, and the marine environment may serve as a reservoir for antibiotic-resistant bacteria. This study determined the antibiotic sensitivity profile of S. aureus isolated from selected beach water and intertidal beach sand in the Eastern Cape Province of South Africa. Methods: Two hundred and forty-nine beach sand and water samples were obtained from 10 beaches from April 2015 to April 2016. Staphylococcus aureus was isolated from the samples using standard microbiological methods and subjected to susceptibility testing to 15 antibiotics. Methicillin-resistant Staphylococcus aureus (MRSA) was detected by susceptibility to oxacillin and growth on Brilliance MRSA II agar. Antibiotic resistance genes including mecA, femA rpoB, blaZ, ermB, ermA, ermC, vanA, vanB, tetK and tetM were screened. Results: Thirty isolates (12.3%) were positive for S. aureus by PCR with over 50% showing phenotypic resistance to methicillin. Resistance of S. aureus to antibiotics varied considerably with the highest resistance recorded to ampicillin and penicillin (96.7%), rifampicin and clindamycin (80%), oxacillin (73.3%) and erythromycin (70%). S. aureus revealed varying susceptibility to imipenem (96.7%), levofloxacin (86.7%), chloramphenicol (83.3%), cefoxitin (76.7%), ciprofloxacin (66.7%), gentamycin (63.3%), tetracycline and sulfamethoxazole-trimethoprim (56.7%), and vancomycin and doxycycline (50%). All 30 (100%) S. aureus isolates showed multiple antibiotic-resistant patterns (resistant to three or more antibiotics). The mecA, femA, rpoB, blaZ, ermB and tetM genes were detected in 5 (22.7%), 16 (53.3%), 11 (45.8%), 16 (55.2%), 15 (71.4%), and 8 (72.7%) isolates respectively; Conclusions: Results from this study indicate that beach water and sand from the Eastern Cape Province of South Africa may be potential reservoirs of antibiotic-resistant S. aureus which could be transmitted to exposed humans and animals.
Variations in the Rate of Infestations of Dogs with Zoonotic Nematodes and the Contamination of Soil in Different Environments
Authors: Studzińska Maria Bernadeta , Demkowska-Kutrzepa Marta , Borecka Anna , Meisner Michał , Tomczuk Krzysztof , Roczeń-Karczmarz Monika , Kłapeć Teresa , Abbass Zahrai , Cholewa Alicja
Published: September 2017

Companion animals are an important aspect in human life. However, they may also be considered a source of pathogens. An example of zoonotic parasitoses is toxocarosis or cutaneous larva migrans (CLM). The aim of the study was to detect zoonotic nematodes of dogs living in different areas and the intensity of contamination in parasite polluted environments that are hazardous to human health. The fecal samples were examined using standard flotation and decantation methods as well as McMaster’s quantitative technique. The soil samples in urban and rural areas were examined using a modified flotation method as described by Quinn et al. Statistical analyses were performed by IBM SPSS Statistics Version 23. The overall prevalence of parasites in dogs was 38%, 17.02% and 56.60% from urban and rural areas, respectively. The percentage values of nematodes important for human health (Toxocara canis, Ancylostomatidae, Trichuris vulpis) remained at the same level (16%). The infected dogs were dominated by a single parasite species, the main was T. canis (28.95%). In total, 54.30% of the soil samples were contaminated with parasite eggs. The contamination of urban and rural sandpits was 40% and 60%, respectively. The molecular examinations of soil samples using LAMP (loop-mediated isothermal amplification) confirmed the presence of nematode eggs of the species T. canis in all samples previously classified as positive
An Assessment of the Food and Nutrition Security Status of Weaned 7–12 Months Old Children in Rural and Peri-Urban Communities of Gauteng and Limpopo Provinces, South Africa
Authors: Ntila Sithandiwe , Siwela Muthulisi , Kolanisi Unathi , Abdelgadir Hafiz , Ndhlala Ashwell
Published: September 2017

This study assessed the food and nutrition security status of children receiving complementary food in rural and peri-urban communities. A group of 106 mothers from Lebowakgomo village and Hammanskraal Township, respectively, participated in the survey. Additionally, six focus group discussions were conducted per study area to assess the mothers’ perceptions about children’s food access. The Children’s Food Insecurity Access Scale (CFIAS) was used to assess the food security status (access) of the children. The Individual Dietary Diversity Score (IDDS) together with the unquantified food consumption frequency survey were used as a proxy measure of the nutritional quality of the children’s diets. The age and weight of the children obtained from the children’s clinic health cards were used to calculate Weight-for-Age Z scores (WAZ) in order to determine the prevalence of underweight children. The findings showed that a large percentage of children were severely food-insecure, 87% and 78%, in rural and peri-urban areas, respectively. Additionally, Lebowakgomo children (23.6%) and Hammanskraal children (17.9%) were severely underweight. Overall, children’s diets in both study areas was characterized by nutrient-deficient complementary foods. Cheaper foods with a longer stomach-filling effect such as white maize meal and sugar were the most commonly purchased and used. Hence, the children consumed very limited amounts of foods rich in proteins, minerals, and vitamins, which significantly increased the risk of their being malnourished.
Closing Data Gaps with Citizen Science? Findings from the Danube Region
Authors: Lisjak Josip , Schade Sven , Kotsev Alexander
Published: September 2017

Although data is increasingly shared online and accessible for re-use, we still witness heterogeneous coverage of thematic areas and geographic regions. This especially becomes an issue when data is needed for large territories and including different nations, as, for example, required to support macro-regional development policies. Once identified, data gaps might be closed using different approaches. Existing—but so far non accessible—data might be made available; new public sector information could be gathered; or data might be acquired from the private sector. Our work explores a fourth option: closing data gaps with direct contributions from citizen (Citizen Science). This work summarizes a particular case study that was conducted in 2016 in the Danube Region. We provide a gap analysis over an existing macro-regional data infrastructure, and examine potential Citizen Science approaches that might help to close these gaps. We highlight already existing Citizen Science projects that could address a large part of the identified gaps, and suggest one particular new application in order to indicate how a—so far uncovered—gap might be approached. This new application addresses bioenergy as a particular field of the circular economy. On this basis we discuss the emerging opportunities and challenges for this particular way of public participation in regional development policy. We close by highlighting areas for future research.
Bromopropane Compounds Increase the Stemness of Colorectal Cancer Cells
Authors: Cho Young-Chang , Nguyen Thanh , Park So-Yeon , Kim Kwonseop , Kim Hyung , Jeong Hye , Kim Kyung , Kim Hangun
Published: September 2017

Bromopropane (BP) compounds, including 1-bromopropane, 2-bromopropane, and 1,2-dibromopropane, are used in industry for various purposes, and their deleterious effects on human health are becoming known. In this study, we examined the effects of BP compounds on the stemness of colorectal cancer cells. At low, non-cytotoxic concentrations, BP compounds significantly increased spheroid formation in CSC221, DLD1, Caco2, and HT29 cells. In addition, the levels of cancer stem cell markers, such as aldehyde dehydrogenase-1, cluster of differentiation 133 (CD133), CD44, Lgr5, Musashi-1, Ephrin receptor, and Bmi-1 increased after exposure to BP compounds. BP compounds increased the transcriptional activity of the TOPflash and glioma-associated oncogene homolog zinc finger protein (Gli) promoters in reporter assays and increased the expression of Gli-1, Gli-2, Smoothened (SMO), and β-catenin by RT-PCR. These results demonstrate for the first time that BP compounds have the potential to promote cancer stemness.
Brassica-Derived Plant Bioactives as Modulators of Chemopreventive and Inflammatory Signaling Pathways
Authors: Sturm Christine , Wagner Anika E.
Published: September 2017

A high consumption of vegetables belonging to the Brassicaceae family has been related to a lower incidence of chronic diseases including different kinds of cancer. These beneficial effects of, e.g., broccoli, cabbage or rocket (arugula) intake have been mainly dedicated to the sulfur-containing glucosinolates (GLSs)—secondary plant compounds nearly exclusively present in Brassicaceae—and in particular to their bioactive breakdown products including isothiocyanates (ITCs). Overall, the current literature indicate that selected Brassica-derived ITCs exhibit health-promoting effects in vitro, as well as in laboratory mice in vivo. Some studies suggest anti-carcinogenic and anti-inflammatory properties for ITCs which may be communicated through an activation of the redox-sensitive transcription factor nuclear factor erythroid 2–related factor 2 (Nrf2) that controls the expression of antioxidant and phase II enzymes. Furthermore, it has been shown that ITCs are able to significantly ameliorate a severe inflammatory phenotype in colitic mice in vivo. As there are studies available suggesting an epigenetic mode of action for Brassica-derived phytochemicals, the conduction of further studies would be recommendable to investigate if the beneficial effects of these compounds also persist during an irregular consumption pattern.
Locomotion Inhibition of Cimex lectularius L. Following Topical, Sublethal Dose Application of the Chitin Synthesis Inhibitor Lufenuron
Authors: Campbell Brittany , Baldwin Rebecca , Koehler Philip
Published: September 2017

To date, few studies have evaluated chitin synthesis inhibitors against bed bugs, although they would provide an alternative mode of action to circumvent insecticide resistance. Acute and sublethal effects of lufenuron were evaluated against two strains of the common bed bug. Combined acute and sublethal effects were used to calculate effective doses. The dose that was effective against 50% of Harlan strain bed bugs was 0.0081% (w/v), and was much higher against Bradenton strain bed bugs (1.11% w/v). Sublethal doses were chosen to determine the effect that leg abnormalities had on pulling force. Both Harlan and Bradenton strain bed bugs had significantly lower locomotion ability (p < 0.0001) following topical application of lufenuron. The observed sublethal effects that limit locomotion could prevent bed bugs from moving within a domicile and taking a blood meal, subsequently reducing a bed bug population over time.
The Effect of Precipitate Evolution on Austenite Grain Growth in RAFM Steel
Authors: Yan Biyu , Liu Yongchang , Wang Zejun , Liu Chenxi , Si Yonghong , Li Huijun , Yu Jianxing
Published: September 2017

To study the effects of various types of precipitates and precipitate evolution behavior on austenite (size and phase fraction) in reduced activation ferritic/martensitic (RAFM) steel, RAFM steel was heated to various austenitizing temperatures. The microstructures of specimens were observed using optical microscopy (OM) and transmission electron microscopy (TEM). The results indicate that the M23C6 and MX precipitates gradually coarsen and dissolve into the matrix as the austenitizing temperatures increase. The M23C6 precipitates dissolve completely at 1100 °C, while the MX precipitates dissolve completely at 1200 °C. The evolution of two types of precipitate has a significant effect on the size of austenite. Based on the Zener pinning model, the effect of precipitate evolution on austenite grain size is quantified. It was found that the coarsening and dissolution of M23C6 and MX precipitates leads to a decrease in pinning pressure on grain boundaries, facilitating the rapid growth of austenite grains. The austenite phase fraction is also affected by the coarsening and dissolution of precipitates.
Pharmacokinetics of Jaspine B and Enhancement of Intestinal Absorption of Jaspine B in the Presence of Bile Acid in Rats
Authors: Choi Min-Koo , Lee Jihoon , Nam So , Kang Yun , Han Youjin , Choi Kwangik , Choi Young , Kwon Mihwa , Lee Dongjoo , Song Im-Sook
Published: September 2017

We aimed to investigate the pharmacokinetics and the underlying mechanisms of the intestinal absorption, distribution, metabolism, and excretion of Jaspine B in rats. The oral bioavailability of Jaspine B was 6.2%, but it decreased to 1.6% in bile-depleted rats and increased to 41.2% (normal) and 23.5% (bile-depleted) with taurocholate supplementation (60 mg/kg). Consistent with the increased absorption in the presence of bile salts, rat intestinal permeability of Jaspine B also increased in the presence of 10 mM taurocholate or 20% bile. Further studies demonstrated that the enhanced intestinal permeability with bile salts was due to increased lipophilicity and decreased membrane integrity. Jaspine B was designated as a highly tissue-distributed compound, because it showed large tissue to plasma ratios in the brain, kidney, heart, and spleen. Moreover, the recovery of Jaspine B from the feces and urine after an intravenous administration was about 6.3%, suggesting a substantial metabolism of Jaspine B. Consistent with this observation, 80% of the administered Jaspine B was degraded after 1 h incubation with rat liver microsomes. In conclusion, the facilitated intestinal permeability in the presence of bile salts could significantly increase the bioavailability of Jaspine B and could lead to the development of oral formulations of Jaspine B with bile salts. Moreover, the highly distributed features of Jaspine B in the brain, kidney, heart, and spleen should be carefully considered in the therapeutic effect and toxicity of this compound.
Biological and Chemical Diversity of Bacteria Associated with a Marine Flatworm
Authors: Lin Hui-Na , Wang Kai-Ling , Wu Ze-Hong , Tian Ren-Mao , Liu Guo-Zhu , Xu Ying
Published: September 2017

The aim of this research is to explore the biological and chemical diversity of bacteria associated with a marine flatworm Paraplanocera sp., and to discover the bioactive metabolites from culturable strains. A total of 141 strains of bacteria including 45 strains of actinomycetes and 96 strains of other bacteria were isolated, identified and fermented on a small scale. Bioactive screening (antibacterial and cytotoxic activities) and chemical screening (ultra-performance liquid chromatography–mass spectrometry (UPLC-MS)) yielded several target bacterial strains. Among these strains, the ethyl acetate (EA) crude extract of Streptomyces sp. XY-FW47 fermentation broth showed strong antibacterial activity against methicillin-resistant Staphylococcus aureus ATCC43300 (MRSA ATCC43300) and potent cytotoxic effects on HeLa cells. The UPLC-MS spectral analysis of the crude extract indicated that the strain XY-FW47 could produce a series of geldanamycins (GMs). One new geldanamycin (GM) analog, 4,5-dihydro-17-O-demethylgeldanamycin (1), and three known GMs (2–4) were obtained. All of these compounds were tested for antibacterial, cytotoxic, and antifungal activities, yet only GM (3) showed potent cytotoxic (HeLa cells, EC50 = 1.12 μg/mL) and antifungal (Setosphaeria turcica MIC = 2.40 μg/mL) activities. Their structure–activity relationship (SAR) was also preliminarily discussed in this study.
Literature Review of Research on Chronic Pain and Yoga in Military Populations
Authors: Miller Shari , Gaylord Susan , Buben Alex , Brintz Carrie , Rae Olmsted Kristine , Asefnia Nakisa , Bartoszek Michael
Published: September 2017

Background: Although yoga is increasingly being provided to active duty soldiers and veterans, studies with military populations are limited and effects on chronic pain are largely unknown. We reviewed the existing body of literature and provide recommendations for future research. Methods: We conducted a literature review of electronic databases (PubMed, PsychINFO, Web of Science, Science Citation Index Expanded, Social Sciences Citation Index, Conference Proceedings Citation Index—Science, and Conference Proceedings Citation Index—Social Science & Humanities). The studies were reviewed for characteristics such as mean age of participants, sample size, yoga type, and study design. Only peer-reviewed studies were included in the review. Results: The search yielded only six studies that examined pain as an outcome of yoga for military populations. With one exception, studies were with veteran populations. Only one study was conducted with Operation Enduring Freedom (OEF) or Operation Iraqi Freedom (OIF) veterans. One study was a randomized controlled trial (RCT). Four of the five studies remaining used pre/post design, while the last study used a post-only design. Conclusions: Studies on the use of yoga to treat chronic pain in military populations are in their infancy. Methodological weaknesses include small sample sizes, a lack of studies with key groups (active duty, OEF/IEF veterans), and use of single group uncontrolled designs (pre/post; post only) for all but one study. Future research is needed to address these methodological limitations and build on this small body of literature.
Steel Weld Metal Deposit Measured Properties after Immediate Micro-Jet Cooling
Authors: Szczucka-Lasota Bożena , Gajdzik Bożena , Węgrzyn Tomasz , Wszołek Łukasz
Published: September 2017

The aim of this paper is to present a welding process connected with micro-jet cooling. This method allowed us to guide the metallographic structure, and furthermore, the properties of the weld metal deposit. The main conclusion of this paper was that after welding with micro-jet cooling, it was possible to achieve beneficial metallographic structures that are impossible to obtain in any other way. These structures corresponded to very good mechanical properties of the welds. The research results described the influence of an artificially enhanced amount of acicular ferrite in the weld metal deposit (WMD) even above 65% when using micro-jet cooling. The results of this process were very positive due to the very high impact toughness of welds at negative temperature. The main parameters of micro-jet cooling are: cooling stream diameter (about 60 µm), gas pressure (about 0.6 MPa), the use of various gases and gas mixtures (main micro-jet gases: argon, helium, nitrogen, carbon dioxide, oxygen, air).
Definition of a First Process Window for Purification of Aluminum via “Cooled Finger” Crystallization Technique
Authors: Curtolo Danilo , Friedrich Semiramis , Bellin Dominic , Nayak Gargi , Friedrich Bernd
Published: September 2017

Aluminum ultra-purification is commonly realized through a combination of three-layer electrolytic refining and fractional crystallization, mostly using zone melting. In order to achieve a purity over 6N with the aid of zone melting, many passes have to be performed, taking several days to be accomplished. This paper focuses on a fractional crystallization methodology using a rotating and internally gas cooled crystallizer (“cooled finger”), based on a Japanese patent from the 1980s, about which no scientific investigation or publication has yet been found. This paper focuses on the impact of process conditions (mainly cooling gas flow and rotation velocity) on the growth rate of the crystallized material as well as on the reduction factor of the impurities Fe, Si, Pb, and Zn in aluminum in relationship to their initial concentration and their interaction in a multi-component system. This technique can be considered as a promising alternative for purification of aluminum as well as other metallic systems.
Visualization Study of Oil-in-Water-in-Oil (O/W/O) Double Emulsion Formation in a Simple and Robust Co-Flowing Microfluidic Device
Authors: Lu Pengfei , Wu Liangyu , Liu Xiangdong
Published: September 2017

A simple and robust co-flowing microfluidic device for double emulsion preparation is designed and assembled to visually study the double emulsion formation by the use of a microscope and high-speed camera. Using a visualization system, the transient processes of double emulsion formation in co-flowing stream are observed and recorded for a variety of flow rates. The effects of flow rates of each fluid on flow modes, drop sizes, and polydispersities are examined and analyzed. The results indicate that the detaching of the inner drops accelerates the detaching of the outer drops and speeds up the drop formation process of double emulsions. The manipulation of flow rates is capable to actively control the sizes of the inner and outer drops as well as the number of inner drops encapsulated. Without surface modification, the microfluidic device produces a variety of emulsions, including the single-core and multi-core O/W/O double emulsions as well as binary emulsions of single and double emulsions. The proposed co-flowing microfluidic device is highly desirable in producing double emulsions in an easy and cheap way.
Miniaturization of Implantable Micro-Robot Propulsion Using a Wireless Power Transfer System
Authors: Kim Dongwook , Hwang Karam , Park Jaehyoung , Park Hyun , Ahn Seungyoung
Published: September 2017

This paper presents an efficient coil design for a mm-sized micro-robot which generates a propulsion force and torque and receives electrical energy using a wireless power transfer system. To determine the most efficient coil structures and produce propulsion and torque on the micro-robot, both helical and spiral coil modeling was conducted, and analytical formulations of the propulsion force and torque were derived for helical and spiral coil structures. Additionally, the dominant dimensional factors for determining propulsion and coil torque were analyzed in detail. Based on the results, an optimum coil structure for generating maximum force on the micro-robot was developed and is herein presented with dimensional analysis. Simulations and experiments were also conducted to verify the design, and good agreement was achieved. A 3-mm micro-robot that simultaneously generated a propulsion force and torque and received electrical energy via wireless power transfer was successfully fabricated using the proposed method and verified.
Flotation Behavior of Different Colored Fluorites Using Sodium Oleate as a Collector
Authors: Zheng Renji , Ren Zijie , Gao Huimin , Qian Yupeng
Published: September 2017

Using sodium oleate (NaOL) as a collector, the flotation characteristics of natural colorless fluorite (CF), green fluorite (GF), and purple fluorite (PF) were investigated through micro-flotation tests, collector adsorption measurements, and surface tension measurement. The micro-flotation results indicated that CF had a much better flotation response than both GF and PF, and had higher floatation recovery. The results demonstrated a considerable discrepancy in the interfacial properties between colorless and colored fluorite, even though all the samples were obtained from the same deposit, holding a similar high purity of CaF2. The adsorption capacity of CF, GF, and PF for NaOL was 2.27, 4.18, and 8.21 × 10−6 mol/g under neutral conditions, respectively. Fourier transform infrared (FT-IR) measurements revealed that the carboxyl groups of NaOL reacted with Ca sites on the surface of fluorites by chemical adsorption. From the zeta potential analyses, PF exhibited a lower positive potential than CF and GF, mainly due to its surface carbonation. In the presence of NaOL, the surface potential of fluorites changed from positive to negative because the NaOL collector had been adsorbed onto the mineral surface and changed their surface potential, which was consistent with the flotation results at different pH values. We found that the floatability of the fluorite samples was influenced by their surface roughness, measured by an atomic force microscope (AFM) and scanning electron microscope (SEM). PF can be floated with adding more reagent dosage than CF and GF to compensate for its higher surface roughness.
Constituents of the Fruits of Citrus medica L. var. sarcodactylis and the Effect of 6,7-Dimethoxy-coumarin on Superoxide Anion Formation and Elastase Release
Authors: Chan Yu-Yi , Hwang Tsong-Long , Kuo Ping-Chung , Hung Hsin-Yi , Wu Tian-Shung
Published: September 2017

Investigation of the chemical constituents from the fruits of Citrus medica L. var. sarcodactylis Swingle has led to the characterization of a new sesquiterpene 1 along with thirty-two known compounds. The structure of 1 was established on the basis of 2D NMR spectroscopic and mass spectrometric analyses, and the known compounds were identified by comparison of their physical and spectroscopic data with those reported in the literature. In addition, most of the isolated compounds were evaluated for the activity assayed by the in vitro inhibition of superoxide anion generation and elastase release by human neutrophils. The results showed that only 6,7-dimethoxycoumarin (5) exhibited significant inhibition of superoxide anion generation, with IC50 value of 3.8 ± 1.4 μM.