bluuebunny/crossref_metadata_2025 huggingface dataset:
Influential Factors and Dry Deposition of Polychlorinated Biphenyls (PCBs) in Atmospheric Particles at an Isolated Island (Pingtan Island) in Fujian Province, China
Authors: Lao Qibin , Jiao Liping , Chen Fajin , Chen Liqi , Sun Xia
Published: February 2018

To explore the polychlorinated biphenyl (PCB) pollution characteristics of atmospheric particles, influential factors, and dry deposition fluxes, 28 PCB congeners were examined over a 2-year period in the environment of an isolated island in Fujian Province. In 2006 and 2007, PCB concentrations ranged from 1.12 to 87.32 pg m−3 and ND (not detected) to 44.93 pg m−3, respectively, and were predominantly highly-chlorinated PCBs. The levels were much lower than those from industrial, urban, and rural areas, but slightly higher than those found in coastal areas of Europe and in the ocean. Obvious seasonal variations were found in the PCB levels, with high levels appearing in the winter, whereas low levels appeared in the summer, which indicated a significant positive correlation with the atmospheric particle mass level. The distribution pattern of the PCB concentration was largely affected by the meteorological conditions and total organic carbon (TOC) levels. Moreover, air mass originating from Northern China may be responsible for the higher PCB levels over Pingtan Island during the winter, and tracing the source of atmospheric particles by the stable carbon isotope suggested that the PBC levels may be influenced by coal combustion during the “heating season” of Northern China. The total dry deposition flux of the 28 PCBs on Pingtan Island was 3.94 ng m−2 d−1 and 2.94 ng m−2 d−1 in 2006 and 2007, respectively, and the average yearly input to the adjacent waters was 7531.2 g y−1.
Neuroprotective Effects of Bioactive Compounds and MAPK Pathway Modulation in “Ischemia”—Stressed PC12 Pheochromocytoma Cells
Authors: Lahiani Adi , Brand-Yavin Annette , Yavin Ephraim , Lazarovici Philip
Published: February 2018

This review surveys the efforts taken to investigate in vitro neuroprotective features of synthetic compounds and cell-released growth factors on PC12 clonal cell line temporarily deprived of oxygen and glucose followed by reoxygenation (OGD/R). These cells have been used previously to mimic some of the properties of in vivo brain ischemia-reperfusion-injury (IRI) and have been instrumental in identifying common mechanisms such as calcium overload, redox potential, lipid peroxidation and MAPKs modulation. In addition, they were useful for establishing the role of certain membrane penetrable cocktails of antioxidants as well as potential growth factors which may act in neuroprotection. Pharmacological mechanisms of neuroprotection addressing modulation of the MAPK cascade and increased redox potential by natural products, drugs and growth factors secreted by stem cells, in either undifferentiated or nerve growth factor-differentiated PC12 cells exposed to ischemic conditions are discussed for future prospects in neuroprotection studies.
Coordinated Interpersonal Behaviour in Collective Dance Improvisation: The Aesthetics of Kinaesthetic Togetherness
Authors: Himberg Tommi , Laroche Julien , Bigé Romain , Buchkowski Megan , Bachrach Asaf
Published: February 2018

Collective dance improvisation (e.g., traditional and social dancing, contact improvisation) is a participatory, relational and embodied art form which eschews standard concepts in aesthetics. We present our ongoing research into the mechanisms underlying the lived experience of “togetherness” associated with such practices. Togetherness in collective dance improvisation is kinaesthetic (based on movement and its perception), and so can be simultaneously addressed from the perspective of the performers and the spectators, and be measured. We utilise these multiple levels of description: the first-person, phenomenological level of personal experiences, the third-person description of brain and body activity, and the level of interpersonal dynamics. Here, we describe two of our protocols: a four-person mirror game and a ‘rhythm battle’ dance improvisation score. Using an interpersonal closeness measure after the practice, we correlate subjective sense of individual/group connectedness and observed levels of in-group temporal synchronization. We propose that kinaesthetic togetherness, or interpersonal resonance, is integral to the aesthetic pleasure of the participants and spectators, and that embodied feeling of togetherness might play a role more generally in aesthetic experience in the performing arts.
Liver Transplantation for Alcoholic Liver Disease and Hepatocellular Carcinoma
Authors: Burra Patrizia , Zanetto Alberto , Germani Giacomo
Published: February 2018

Hepatocellular carcinoma is one of the main important causes of cancer-related death and its mortality is increasingly worldwide. In Europe, alcohol abuse accounts for approximately half of all liver cancer cases and it will become the leading cause of hepatocellular carcinoma in the next future with the sharp decline of chronic viral hepatitis. The pathophysiology of alcohol-induced carcinogenesis involves acetaldehyde catabolism, oxidative stress and chronic liver inflammation. Genetic background plays also a significant role and specific patterns of gene mutations in alcohol-related hepatocellular carcinoma have been characterized. Survival is higher in patients who undergo specific surveillance programmes than in patients who do not. However, patients with alcohol cirrhosis present a significantly greater risk of liver decompensation than those with cirrhosis due to other aetiologies. Furthermore, the adherence to screening program can be suboptimal. Liver transplant for patients with Milan-in hepatocellular carcinoma represents the best possible treatment in case of tumour recurrence/progression despite loco-regional or surgical treatments. Long-term result after liver transplantation for alcohol related liver disease is good. However, cardiovascular disease and de novo malignancies can significantly hamper patients’ survival and should be carefully considered by transplant team. In this review, we have focused on the evolution of alcohol-related hepatocellular carcinoma epidemiology and risk factors as well as on liver transplantation in alcoholic patients with and without hepatocellular carcinoma.
New Trendy Magnetic C-Scorpionate Iron Catalyst and Its Performance towards Cyclohexane Oxidation
Authors: Ribeiro Ana , Matias Inês , Alegria Elisabete , Ferraria Ana , Botelho do Rego Ana , Pombeiro Armando , Martins Luísa
Published: February 2018

For the first time, a magnetic C-scorpionate catalyst was prepared from the iron(II) complex [FeCl2{κ3-HC(pz)3}] (pz = pyrazol-1-yl) and ferrite, using the sustainable mechanochemical synthetic procedure. Its catalytic activity for the cyclohexane oxidation with tert-butyl hydroperoxide (TBHP) was evaluated in different conditions, namely under microwave irradiation and under the effect of an external magnetic field. The use of such magnetic conditions significantly shifted the catalyst alcohol/ketone selectivity, thus revealing a promising, easy new protocol for tuning selectivity in important catalytic processes.
New Electrospun Polystyrene/Al2O3 Nanocomposite Superhydrophobic Coatings; Synthesis, Characterization, and Application
Authors: Bahgat Radwan Ahmed , Abdullah Aboubakr , Mohamed Adel , Al-Maadeed Mariam
Published: February 2018

The effect of electrospinning operational parameters on the morphology, surface roughness, and wettability of different compositions of electrospun polystyrene (PS)–aluminum oxide (Al2O3) nanocomposite coatings was investigated using different techniques. For example, a scanning electron microscope (SEM) coupled with an energy dispersive X-ray (EDX) unit, a Fourier transform infrared (FTIR) spectrometer, an atomic force microscope (AFM), and water contact angle (WCA), and contact angle hysteresis (CAH) measurements using the sessile droplet method, were used. The latter used 4 µL of distilled water at room temperature. PS/Al2O3 nanocomposite coatings exhibited different morphologies, such as beaded fibers and microfibers, depending on the concentration ratio between the PS and Al2O3 nanoparticles and the operational parameters of the electrospinning process. The optimum conditions to produce a nanocomposite coating with the highest roughness and superhydrophobic properties (155° ± 1.9° for WCA and 3° ± 4.2° for CAH) are 2.5 and 0.25 wt % of PS and Al2O3, respectively, 25 kV for the applied potential and 1.5 mL·h−1 for the solution flow rate at 35 °C. The corrosion resistance of the as-prepared coatings was investigated using the electrochemical impedance spectroscopy (EIS) technique. The results have revealed that the highly porous superhydrophobic nanocomposite coatings (SHCs) possess a superior corrosion resistance that is higher than the uncoated Al alloy by three orders of magnitude.
Effects of the Oxide Coating Thickness on the Small Flaw Sizing Using an Ultrasonic Test Technique
Authors: Miao Xiujuan , Li Xiongbing , Hu Hongwei , Gao Guangjun , Zhang Shuzeng
Published: February 2018

When magnesium alloys are tested using ultrasonic techniques, their oxide coating will affect the transmitted ultrasonic energy and the accuracy of the flaw sizing. In this work, the effects of the coating thickness on the flaw sizing are investigated. An ultrasonic measurement model is employed to predict the flaw response signal, and the reflected and transmitted ultrasonic energy in the coated surface are corrected by modifying the reflection and transmission coefficients related to the effects of the coating thickness. The effectiveness of these coefficients and the ultrasonic measurement model are verified through experiments. With the correction of the coating thickness effects, the flaw-sizing curves predicted using the ultrasonic measurement model are provided. The flaws in magnesium alloy specimens with different coating thicknesses are tested, and the determined flaw sizes from these curves agree well with the actual sizes, which reveals the effectiveness of the proposed work. This work provides an effective tool to improve the flaw sizing performance using ultrasonic techniques in practical applications.
Energy from Negentropy of Non-Cahotic Systems
Authors: Quarati Piero , Scarfone Antonio , Kaniadakis Giorgio
Published: February 2018

Negative contribution of entropy (negentropy) of a non-cahotic system, representing the potential of work, is a source of energy that can be transferred to an internal or inserted subsystem. In this case, the system loses order and its entropy increases. The subsystem increases its energy and can perform processes that otherwise would not happen, like, for instance, the nuclear fusion of inserted deuterons in liquid metal matrix, among many others. The role of positive and negative contributions of free energy and entropy are explored with their constraints. The energy available to an inserted subsystem during a transition from a non-equilibrium to the equilibrium chaotic state, when particle interaction (element of the system) is switched off, is evaluated. A few examples are given concerning some non-ideal systems and a possible application to the nuclear reaction screening problem is mentioned.
Adaptive Waveform Design for Cognitive Radar in Multiple Targets Situation
Authors: Zhang Xiaowen , Liu Xingzhao
Published: February 2018

In this paper, the problem of cognitive radar (CR) waveform optimization design for target detection and estimation in multiple extended targets situations is investigated. This problem is analyzed in signal-dependent interference, as well as additive channel noise for extended targets with unknown target impulse response (TIR). To address this problem, an improved algorithm is employed for target detection by maximizing the detection probability of the received echo on the promise of ensuring the TIR estimation precision. In this algorithm, an additional weight vector is introduced to achieve a trade-off among different targets. Both the estimate of TIR and transmit waveform can be updated at each step based on the previous step. Under the same constraint on waveform energy and bandwidth, the information theoretical approach is also considered. In addition, the relationship between the waveforms that are designed based on the two criteria is discussed. Unlike most existing works that only consider single target with temporally correlated characteristics, waveform design for multiple extended targets is considered in this method. Simulation results demonstrate that compared with linear frequency modulated (LFM) signal, waveforms designed based on maximum detection probability and maximum mutual information (MI) criteria can make radar echoes contain more multiple-target information and improve radar performance as a result.
A Study on Electrofuels in Aviation
Authors: Goldmann Andreas , Sauter Waldemar , Oettinger Marcel , Kluge Tim , Schröder Uwe , Seume Joerg , Friedrichs Jens , Dinkelacker Friedrich
Published: February 2018

With the growth of aviation traffic and the demand for emission reduction, alternative fuels like the so-called electrofuels could comprise a sustainable solution. Electrofuels are understood as those that use renewable energy for fuel synthesis and that are carbon-neutral with respect to greenhouse gas emission. In this study, five potential electrofuels are discussed with respect to the potential application as aviation fuels, being n-octane, methanol, methane, hydrogen and ammonia, and compared to conventional Jet A-1 fuel. Three important aspects are illuminated. Firstly, the synthesis process of the electrofuel is described with its technological paths, its energy efficiency and the maturity or research need of the production. Secondly, the physico-chemical properties are compared with respect to specific energy, energy density, as well as those properties relevant to the combustion of the fuels, i.e., autoignition delay time, adiabatic flame temperature, laminar flame speed and extinction strain rate. Results show that the physical and combustion properties significantly differ from jet fuel, except for n-octane. The results describe how the different electrofuels perform with respect to important aspects such as fuel and air mass flow rates. In addition, the results help determine mixture properties of the exhaust gas for each electrofuel. Thirdly, a turbine configuration is investigated at a constant operating point to further analyze the drop-in potential of electrofuels in aircraft engines. It is found that electrofuels can generally substitute conventional kerosene-based fuels, but have some downsides in the form of higher structural loads and potentially lower efficiencies. Finally, a preliminary comparative evaluation matrix is developed. It contains specifically those fields for the different proposed electrofuels where special challenges and problematic points are seen that need more research for potential application. Synthetically-produced n-octane is seen as a potential candidate for a future electrofuel where even a drop-in capability is given. For the other fuels, more issues need further research to allow the application as electrofuels in aviation. Specifically interesting could be the combination of hydrogen with ammonia in the far future; however, the research is just at the beginning stage.
An Improved Rate-Transient Analysis Model of Multi-Fractured Horizontal Wells with Non-Uniform Hydraulic Fracture Properties
Authors: He Youwei , Cheng Shiqing , Rui Zhenhua , Qin Jiazheng , Fu Liang , Shi Jianguo , Wang Yang , Li Dingyi , Patil Shirish , Yu Haiyang , Lu Jun
Published: February 2018

Although technical advances in hydraulically fracturing and drilling enable commercial production from tight reservoirs, oil/gas recovery remains at a low level. Due to the technical and economic limitations of well-testing operations in tight reservoirs, rate-transient analysis (RTA) has become a more attractive option. However, current RTA models hardly consider the effect of the non-uniform production on rate decline behaviors. In fact, PLT results demonstrate that production profile is non-uniform. To fill this gap, this paper presents an improved RTA model of multi-fractured horizontal wells (MFHWs) to investigate the effects of non-uniform properties of hydraulic fractures (production of fractures, fracture half-length, number of fractures, fracture conductivity, and vertical permeability) on rate transient behaviors through the diagnostic type curves. Results indicate obvious differences on the rate decline curves among the type curves of uniform properties of fractures (UPF) and non-uniform properties of fractures (NPF). The use of dimensionless production integral derivative curve magnifies the differences so that we can diagnose the phenomenon of non-uniform production. Therefore, it’s significant to incorporate the effects of NPF into the RDA models of MFHWs, and the model proposed in this paper enables us to better evaluate well performance based on long-term production data.
On the Performance Optimization of Two-Level Three-Phase Grid-Feeding Voltage-Source Inverters
Authors: Smadi Issam , Albatran Saher , Ahmad Hamzeh
Published: February 2018

The performance optimization of the two-level, three-phase, grid-feeding, voltage-source inverter (VSI) is studied in this paper, which adopts an online adaptive switching frequency algorithm (OASF). A new degree of freedom has been added to the employed OASF algorithm for optimal selection of the weighting factor and overall system optimization design. Toward that end, a full mathematical formulation, including the impact of the coupling inductor and the controller response time, is presented. At first, the weighting factor is selected to favor the switching losses, and the controller gains are optimized by minimizing the integral time-weighted absolute error (ITAE) of the output active and reactive power. Different loading and ambient temperature conditions are considered to validate the optimized controller and its fast response through online field programmable gate array (FPGA)-in-the-loop. Then, the weighting factor is optimally selected to reduce the cost of the L-filter and the heat-sink. An optimization problem to minimize the cost design at the worst case of loading condition for grid-feeding VSI is formulated. The results from this optimization problem are the filter inductance, the thermal resistance of the heat-sink, and the optimal switching frequency with the optimal weighting factor. The VSI test-bed using the optimized parameters is used to verify the proposed work experimentally. Adopting the OASF algorithm that employs the optimal weighting factor for grid-feeding VSI, the percentages of the reductions in the slope of the steady state junction temperature profile compared to fixed frequencies of 10 kHz, 14.434 kHz, and 20 kHz are about 6%, 30%, and 18%, respectively.
Improving Control Efficiency of Dynamic Street Lighting by Utilizing the Dual Graph Grammar Concept
Authors: Wojnicki Igor , Kotulski Leszek
Published: February 2018

The paper introduces a definition of dual graph grammar. It enables two graphs to share information in a synchronized way. A smart city example application, which is an outdoor lighting control system utilizing the dual graph grammar, is also demonstrated. The system controls dimming of street lights which is based on traffic intensity. Each luminaire’s light level is adjusted individually to comply with the lighting norms to ensure safety. Benefits of applying the dual graph grammar are twofold. First, it increases expressive power of the mathematical model that the system uses. It becomes possible to take into account complex geographical distribution of sensors and logical dependencies among them. Second, it increases the system’s efficiency by reducing the problem size during run-time. Experimental results show a reduction of the computation time by a factor of 2.8. The approach has been verified in practice.
Power Generation Targets from Hot Composite Curves
Authors: Al-Ani Omar , Linke Patrick
Published: February 2018

The paper proposes a simple systematic procedure to target thermodynamic power generation limits from a set of heat source streams. The procedure takes the form of an algebraic targeting approach commonly applied in process heat integration. It allows the designer to quickly determine the maximum amount of power that can theoretically be generated from the available heat in thermodynamic cycles. The paper describes the procedure and is applicability in the context of common data availability for heat source streams in the form of a Composite Curve or Total Site Profile (hot composite curves) commonly developed in heat integration. The application of the procedure is illustrated with examples.
Performance Analysis of Multiple Wave Energy Converters Placed on a Floating Platform in the Frequency Domain
Authors: Lee Hyebin , Poguluri Sunny , Bae Yoon
Published: February 2018

Wind-wave hybrid power generation systems have the potential to become a significant source of affordable renewable energy. However, their strong interactions with both wind- and wave-induced forces raise a number of technical challenges for modelling. The present study undertakes a numerical investigation on multi-body hydrodynamic interaction between a wind-wave hybrid floating platform and multiple wave energy converters (WECs) in a frequency domain. In addition to the exact responses of the platform and the WECs, the power take-off (PTO) mechanism was taken into account for analysis. The coupled hydrodynamic coefficients and wave exciting forces were obtained from WAMIT, the 3D diffraction/radiation solver based on the boundary element method. The overall performance of the multiple WECs is presented and compared with the performance of a single isolated WEC. The analysis showed significant differences in the dynamic responses of the WECs when the multi-body interaction was considered. In addition, the PTO damping effect made a considerable difference to the responses of the WECs. However, the platform response was only minimally affected by PTO damping. With regard to energy capture, the interaction effect of the designed multiple WEC array layout is evaluated. The WEC array configuration showed both constructive and destructive effects in accordance with the incident wave frequency and direction.
A Mixed WLS Power System State Estimation Method Integrating a Wide-Area Measurement System and SCADA Technology
Authors: Jin Tao , Shen Xueyu
Published: February 2018

To address the issue that the phasor measurement units (PMUs) of wide area measurement system (WAMS) are not sufficient for static state estimation in most existing power systems, this paper proposes a mixed power system weighted least squares (WLS) state estimation method integrating a wide-area measurement system and supervisory control and data acquisition (SCADA) technology. The hybrid calculation model is established by incorporating phasor measurements (including the node voltage phasors and branch current phasors) and the results of the traditional state estimator in a post-processing estimator. The performance assessment is discussed through setting up mathematical models of the distribution network. Based on PMU placement optimization and bias analysis, the effectiveness of the proposed method was proved to be accurate and reliable by simulations of different cases. Furthermore, emulating calculation shows this method greatly improves the accuracy and stability of the state estimation solution, compared with the traditional WLS state estimation.
Integration of Photovoltaic Plants and Supercapacitors in Tramway Power Systems
Authors: Ciccarelli Flavio , Di Noia Luigi Pio , Rizzo Renato
Published: February 2018

The growing interest in the use of energy storage systems to improve the performance of tramways has prompted the development of control techniques and optimal storage devices, displacement, and sizing to obtain the maximum profit and reduce the total installation cost. Recently, the rapid diffusion of renewable energy generation from photovoltaic panels has also created a large interest in coupling renewable energy and storage units. This study analyzed the integration of a photovoltaic power plant, supercapacitor energy storage system, and railway power system. Random optimization was used to verify the feasibility of this integration in a real tramway electric system operating in the city of Naples, and the benefits and total cost of this integration were evaluated.
Culture and Density Effects on Tree Quality in Midrotation Non-Thinned Loblolly Pine Plantations
Authors: Green P. , Bullock Bronson , Kane Michael
Published: February 2018

Six non-thinned loblolly pine (Pinus taeda L.) culture × density study sites in the Piedmont and Upper Coastal Plain of the Southeast U.S. were used to examine the effects of two cultural intensities and three planting densities on solid wood potential as well as the proportion and position of product-defining defects (forks, crooks, broken tops). A tree quality index (TQI) was used to grade stems for solid wood potential. The results show that an operational management regime exhibited a higher proportion of trees with solid wood product potential than did a very intensive management regime. Trees subject to operational management exhibited product-defining defects higher on the stem; however, the proportion of stems with defects was not significantly different from the intensive management. Planting densities of 741, 1482, and 2223 trees per hectare (TPH) exhibited a relatively narrow range of the proportion of trees with solid wood product potential that were not significantly different. Density did not have a significant effect on the heights of the product-defining defects. These results show that management intensity and less so planting density, affect the solid wood product potential indicators evaluated and should be considered when making management decisions.
Security and Privacy in Wireless and Mobile Networks
Authors: Kambourakis Georgios , Gomez Marmol Felix , Wang Guojun
Published: February 2018

Currently, at the dawn of 5G networks, and the era of the Internet-of-Things, wireless and mobile networking is becoming increasingly ubiquitous [...]
Fractional Derivatives with the Power-Law and the Mittag–Leffler Kernel Applied to the Nonlinear Baggs–Freedman Model
Authors: Gómez-Aguilar José Francisco , Atangana Abdon
Published: February 2018

This paper considers the Freedman model using the Liouville–Caputo fractional-order derivative and the fractional-order derivative with Mittag–Leffler kernel in the Liouville–Caputo sense. Alternative solutions via Laplace transform, Sumudu–Picard and Adams–Moulton rules were obtained. We prove the uniqueness and existence of the solutions for the alternative model. Numerical simulations for the prediction and interaction between a unilingual and a bilingual population were obtained for different values of the fractional order.
Observing Geohazards from Space
Authors: Cigna Francesca
Published: February 2018

With a wide spectrum of imaging capabilities—from optical to radar sensors, low to very high resolution, continental to local scale, single-image to multi-temporal approaches, yearly to sub-daily acquisition repeat cycles—Earth Observation (EO) offers several opportunities for the geoscience community to map and monitor natural and human-induced Earth hazards from space. The Special Issue “Observing Geohazards from Space” of Geosciences gathers 12 research articles on the development, validation, and implementation of satellite EO data, processing methods, and applications for mapping and monitoring of geohazards such as slow moving landslides, ground subsidence and uplift, and active and abandoned mining-induced ground movements. Papers published in this Special Issue provide novel case studies demonstrating how EO and remote sensing data can be used to detect and delineate land instability and geological hazards in different environmental contexts and using a range of spatial resolutions and image processing methods. Remote sensing datasets used in the Special Issue papers encompass satellite imagery from the ERS-1/2, ENVISAT, RADARSAT-1/2, and Sentinel-1 C-band, TerraSAR-X and COSMO-SkyMed X-band, and ALOS L-band SAR missions; Landsat 7, SPOT-5, WorldView-2/3, and Sentinel-2 multi-spectral data; UAV-derived RGB and near infrared aerial photographs; LiDAR surveying; and GNSS positioning data. Techniques that are showcased include, but are not limited to, differential Interferometric SAR (InSAR) and its advanced approaches such as Persistent Scatterers (PS) and Small Baseline Subset (SBAS) methods to estimate ground deformation, Object-Based Image Analysis (OBIA) to identify landslides in high resolution multi-spectral data, UAV and airborne photogrammetry, Structure-from-Motion (SfM) for digital elevation model generation, aerial photo-interpretation, feature extraction, and time series analysis. Case studies presented in the papers focus on landslides, natural and human-induced subsidence, and groundwater management and mining-related ground deformation in many local to regional-scale study areas in Austria, Belgium, Italy, Slovakia, Spain, and the UK.
ENSO Index-Based Insurance for Agricultural Protection in Southern Peru
Authors: Mortensen Eric , Block Paul
Published: February 2018

Agricultural operations in southern Peru are particularly vulnerable to climate variability due to water resource scarcity. In general, the response to drier than normal conditions in this region is reactive and fairly limited due to challenges associated with climate forecasting and administrative capacity to distribute resources. To shift this paradigm, we investigate the potential for an El Niño–Southern Oscillation index-based insurance product. The article presents a demonstration of methodology and application for one specific crop in a department of southern Peru. The purpose of this product is to streamline the ability of decision makers to provide financial relief to affected farmers during, and perhaps before, drought; extending the lead-time of the index that is used to trigger product payouts produces results of similar skill to a product trained on concurrent conditions. Issues explored in this work include basis risk, initial endowment requirements, product longevity, and the potential crossover from index-based insurance to forecast-based financing. The ability of such products to mitigate losses during and after drought may be advantageous in Peru and other regions with notable interannual climate variability.
MinInversion: A Program for Petrophysical Composition Analysis of Geophysical Well Log Data
Authors: Amosu Adewale , Sun Yuefeng
Published: February 2018

Knowledge of the composition (mineral and fluid proportions) of rock formation lithologies is important for petrophysical and rock physics analysis. The mineralogy of a rock formation can be estimated by solving a system of linear equations that relate a class of geophysical log measurements to the petrophysical properties of known minerals and fluids. This method is useful for carbonate rocks with complex mineralogies and a wide range of other lithologies. Although this method of linear inversion for rock composition is well known, there are no interactive, open-source programs for routinely estimating rock mineralogy from standard digital geophysical wireline logs. We present an interactive open-source program, MinInversion, for constructing a balanced system of linear equations from digital geophysical logs and estimating the rock mineralogy as an inverse problem. MinInversion makes use of a library of petrophysical properties that can be easily expanded and modified by the users. MinInversion also provides several options for solving the system of linear equations and executing the linear matrix inversion including least squares, LU-decomposition and Moore-Penrose generalized inverse methods. In addition, MinInversion enables the estimation of the joint probability distributions for constituent minerals and measured porosity. The joint probability distributions are useful for revealing and analyzing depositional or diagenetic composition trends that affect porosity. The program introduces ease and flexibility to the problems of rock formation composition analysis and the study of the effects of rock composition on porosity.
A Longitudinal Study of Predictors for Adolescent Electronic Cigarette Experimentation and Comparison with Conventional Smoking
Authors: Kinnunen Jaana M. , Ollila Hanna , Minkkinen Jaana , Lindfors Pirjo L. , Rimpelä Arja H.
Published: February 2018

Little is known of the predictors of electronic cigarette (e-cigarette) use among adolescents, even though the use is increasing. We studied here the predictors for e-cigarette experimentation (tried and tried more than twice) and compared them with predictors for conventional smoking. A baseline school survey was conducted in the Helsinki metropolitan area, Finland, in 2011 for seventh graders (12 to 13-year-olds). Response rate was 73%. The same students were followed up in 2014 (9th grade, 15 to 16-year-olds), N = 5742. Generalized linear mixed models controlling for school clustering were used. In the follow-up, 43.3% of boys and 25.6% of girls had tried e-cigarettes and 21.9% and 8.1% correspondingly more than twice. The strongest predictors for both genders were conventional smoking, drunkenness and energy drink use. Furthermore, poor academic achievement predicted e-cigarette experimentation for both genders, and for boys, participation in team sports was a predictor. The predictors for experimenting and for experimenting more than twice were very similar, except for boys’ participation in team sports. They were also similar compared to the predictors of conventional smoking but the associations were weaker. To conclude, smoking and other addictive behaviors predict adolescents’ experimentation with e-cigarettes. Family’s socioeconomic background had little significance.
Dissection of the Mechanism for Compatible and Incompatible Graft Combinations of Citrus grandis (L.) Osbeck (‘Hongmian Miyou’)
Authors: He Wen , Wang Yan , Chen Qing , Sun Bo , Tang Hao-Ru , Pan Dong-Ming , Wang Xiao-Rong
Published: February 2018

‘Hongmian miyou’ (Citrus grandis L. Osbeck) is mutated from ‘Guanxi miyou’, with a different spongy layer coloration. Trifoliate orange (Poncirus trifoliata) is widely used as rootstocks in ‘Guanxi miyou’ grafting, whereas ‘Hongmian miyou’ is incompatible with available trifoliate orange rootstocks. To explore the reasons for the etiolation of leaves of ‘Hongmian miyou’/trifoliate orange, anatomical differences among different graft unions, gene expression profiles, and auxin levels of scion were investigated in this study. A histological assay indicated that there was no significant difference in anatomical structure between the compatible and incompatible combinations. A total of 1950 significant differentially-expressed genes (DEGs) were identified and analyzed. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed that genes involved in carbohydrate metabolism, energy metabolism, amino acid metabolism, and plant hormone signal transduction were significantly enriched. Moreover, the expression of nine genes in the auxin pathway were upregulated and three were downregulated in compatible combinations compared with those in the incompatible group. Further experiments verified that indole-3-acetic acid (IAA) content increases in the compatible graft combination, which suggests that IAA might promote graft compatibility.
Tea Polysaccharide Prevents Colitis-Associated Carcinogenesis in Mice by Inhibiting the Proliferation and Invasion of Tumor Cells
Authors: Liu Li-Qiao , Li Hai-Shan , Nie Shao-Ping , Shen Ming-Yue , Hu Jie-Lun , Xie Ming-Yong
Published: February 2018

The imbalance between cell proliferation and apoptosis can lead to tumor progression, causing oncogenic transformation, abnormal cell proliferation and cell apoptosis suppression. Tea polysaccharide (TPS) is the major bioactive component in green tea, it has showed antioxidant, antitumor and anti-inflammatory bioactivities. In this study, the chemoprophylaxis effects of TPS on colitis-associated colon carcinogenesis, especially the cell apoptosis activation and inhibition effects on cell proliferation and invasion were analyzed. The azoxymethane/dextran sulfate sodium (AOM/DSS) was used to induce the colorectal carcinogenesis in mice. Results showed that the tumor incidence was reduced in TPS-treated AOM/DSS mice compared to AOM/DSS mice. TUNEL staining and Ki-67 immunohistochemistry staining showed that the TPS treatment increased significantly the cell apoptosis and decreased cell proliferation among AOM/DSS mice. Furthermore, TPS reduced the expression levels of the cell cycle protein cyclin D1, matrix metalloproteinase (MMP)-2, and MMP-9. In addition, in vitro studies showed that TPS, suppressed the proliferation and invasion of the mouse colon cancer cells. Overall, our findings demonstrated that TPS could be a potential agent in the treatment and/or prevention of colon tumor, which promoted the apoptosis and suppressed the proliferation and invasion of the mouse colon cancer cells via arresting cell cycle progression.
Lipid Supplement in the Cultural Condition Facilitates the Porcine iPSC Derivation through cAMP/PKA/CREB Signal Pathway
Authors: Zhang Wei , Wang Hanning , Zhang Shaopeng , Zhong Liang , Wang Yanliang , Pei Yangli , Han Jianyong , Cao Suying
Published: February 2018

Large numbers of lipids exist in the porcine oocytes and early embryos and have the positive effects on their development, suggesting that the lipids may play an important role in pluripotency establishment and maintenance in pigs. However, the effects of lipids and their metabolites, such as fatty acids on reprogramming and the pluripotency gene expression of porcine-induced pluripotent stem cells (iPSCs), are unclear. Here, we generated the porcine iPSCs that resemble the mouse embryonic stem cells (ESCs) under lipid and fatty-acid-enriched cultural conditions (supplement of AlbuMAX). These porcine iPSCs show positive for the ESCs pluripotency markers and have the differentiation abilities to all three germ layers, and importantly, have the capability of aggregation into the inner cell mass (ICM) of porcine blastocysts. We further confirmed that lipid and fatty acid enriched condition can promote the cell proliferation and improve reprogramming efficiency by elevating cAMP levels. Interestingly, this lipids supplement promotes mesenchymal–epithelial transition (MET) through the cAMP/PKA/CREB signal pathway and upregulates the E-cadherin expression during porcine somatic cell reprogramming. The lipids supplement also makes a contribution to lipid droplets accumulation in the porcine iPSCs that resemble porcine preimplantation embryos. These findings may facilitate understanding of the lipid metabolism in porcine iPSCs and lay the foundation of bona fide porcine embryonic stem cell derivation.
Deficiency of Invariant Natural Killer T Cells Does Not Protect Against Obesity but Exacerbates Atherosclerosis in Ldlr−/− Mice
Authors: Subramanian Savitha , Goodspeed Leela , Wang Shari , Ding Yilei , O’Brien Kevin , Getz Godfrey , Chait Alan , Reardon Catherine
Published: February 2018

Obesity is a chronic inflammatory state characterized by altered levels of adipose tissue immune cell populations. Natural killer T (NKT) cells are CD1d restricted lymphocyte subsets that recognize lipid antigens whose level decreases in obese adipose tissue. However, studies in mice with deficiency or increased levels of NKT cells have yielded contradictory results, so the exact role of these cells in obesity and adipose tissue inflammation is not yet established. We previously showed that Ldlr−/− mice with excess invariant NKT (iNKT) cells demonstrate significant weight gain, adiposity, metabolic abnormalities, and atherosclerosis. The current study evaluates the effects of NKT cell deficiency on obesity, associated metabolic changes, and atherosclerosis in Jα18−/−Ldlr−/− (lacking iNKT cells) and Cd1d−/−Ldlr−/− (lacking invariant and type II NKT cells) mice, and control mice were fed an obesogenic diet (high fat, sucrose, cholesterol) for 16 weeks. Contrary to expectations, Ja18−/−Ldlr−/− mice gained significantly more weight than Ldlr−/− or Cd1d−/−Ldlr−/− mice, developed hypertriglyceridemia, and had worsened adipose tissue inflammation. All the mice developed insulin resistance and hepatic triglyceride accumulation. Ja18−/−Ldlr−/− mice also had increased atherosclerotic lesion area. Our findings suggest that iNKT cells exacerbates the metabolic, inflammatory, and atherosclerotic features of diet-induced obesity. Further work is required to unravel the paradox of an apparently similar effect of iNKT cell surplus and depletion on obesity.
Plant Responses to Pathogen Attack: Small RNAs in Focus
Authors: Islam Waqar , Noman Ali , Qasim Muhammad , Wang Liande
Published: February 2018

Small RNAs (sRNA) are a significant group of gene expression regulators for multiple biological processes in eukaryotes. In plants, many sRNA silencing pathways produce extensive array of sRNAs with specialized roles. The evidence on record advocates for the functions of sRNAs during plant microbe interactions. Host sRNAs are reckoned as mandatory elements of plant defense. sRNAs involved in plant defense processes via different pathways include both short interfering RNA (siRNA) and microRNA (miRNA) that actively regulate immunity in response to pathogenic attack via tackling pathogen-associated molecular patterns (PAMPs) and other effectors. In response to pathogen attack, plants protect themselves with the help of sRNA-dependent immune systems. That sRNA-mediated plant defense responses play a role during infections is an established fact. However, the regulations of several sRNAs still need extensive research. In this review, we discussed the topical advancements and findings relevant to pathogen attack and plant defense mediated by sRNAs. We attempted to point out diverse sRNAs as key defenders in plant systems. It is hoped that sRNAs would be exploited as a mainstream player to achieve food security by tackling different plant diseases.
Hypoxia Enhances Differentiation of Adipose Tissue-Derived Stem Cells toward the Smooth Muscle Phenotype
Authors: Wang Fang , Zachar Vladimir , Pennisi Cristian , Fink Trine , Maeda Yasuko , Emmersen Jeppe
Published: February 2018

Smooth muscle differentiated adipose tissue-derived stem cells are a valuable resource for regeneration of gastrointestinal tissues, such as the gut and sphincters. Hypoxia has been shown to promote adipose tissue-derived stem cells proliferation and maintenance of pluripotency, but the influence of hypoxia on their smooth myogenic differentiation remains unexplored. This study investigated the phenotype and contractility of adipose-derived stem cells differentiated toward the smooth myogenic lineage under hypoxic conditions. Oxygen concentrations of 2%, 5%, 10%, and 20% were used during differentiation of adipose tissue-derived stem cells. Real time reverse transcription polymerase chain reaction and immunofluorescence staining were used to detect the expression of smooth muscle cells-specific markers, including early marker smooth muscle alpha actin, middle markers calponin, caldesmon, and late marker smooth muscle myosin heavy chain. The specific contractile properties of cells were verified with both a single cell contraction assay and a gel contraction assay. Five percent oxygen concentration significantly increased the expression levels of α-smooth muscle actin, calponin, and myosin heavy chain in adipose-derived stem cell cultures after 2 weeks of induction (p < 0.01). Cells differentiated in 5% oxygen conditions showed greater contraction effect (p < 0.01). Hypoxia influences differentiation of smooth muscle cells from adipose stem cells and 5% oxygen was the optimal condition to generate smooth muscle cells that contract from adipose stem cells.
Fine-Tuning of Gene Expression by tRNA-Derived Fragments during Abiotic Stress Signal Transduction
Authors: Park Eun , Kim Tae-Houn
Published: February 2018

When plants are subjected to unfavorable environmental conditions, overall gene expression in stressed cells is altered from a programmed pattern for normal development to an adaptive pattern for survival. Rapid changes in plant gene expression include production of stress responsive proteins for protection as well as reduction of irrelevant proteins to minimize energy consumption during growth. In addition to the many established mechanisms known to modulate gene expression in eukaryotes, a novel strategy involving tRNA-derived fragments (tRFs) was recently reported to control gene expression. In animals, tRFs are shown to play a certain role in infected or cancer cells. However, tRFs are expected to function in the regulation of gene expression against abiotic stress conditions in plants. Moreover, the underlying mechanism linking up-regulation of tRFs under stress conditions with the stress tolerant response remains unknown. In this review, the biogenesis and putative function of diverse tRFs in abiotic stress signaling are discussed with a focus on tRFs as a transcriptional/post-transcriptional/translational regulator.
De Novo Assembly and Characterization of the Xenocatantops brachycerus Transcriptome
Authors: Zhao Le , Zhang Xinmei , Qiu Zhongying , Huang Yuan
Published: February 2018

Grasshoppers are common pests but also have high nutritional and commercial potential. Xenocatantops brachycerus Willemse (Orthoptera: Acrididae) is an economically important grasshopper species that is reared in China. Using the IlluminaHiSeqTM 4000 platform, three transcriptomes of the adult male, adult female, and nymph of X. brachycerus were sequenced. A total of 133,194,848 clean reads were obtained and de novo assembled into 43,187 unigenes with an average length of 964 bp (N50 of 1799 bp); of these, 24,717 (57.23%) unigenes matched known proteins. Based on these annotations, many putative transcripts related to X. brachycerus growth, development, environmental adaptability, and metabolism of nutritional components and bioactive components were identified. In addition, the expression profiles of all three transcriptome datasets were analyzed, and many differentially expressed genes were detected using RSEM and PossionDis. Unigenes. Unigenes with functions associated with growth and development exhibited higher transcript levels at the nymph stage, and unigenes associated with environmental adaptability showed increased transcription in the adults. These comprehensive X. brachycerus transcriptomic data will provide a useful molecular resource for gene prediction, molecular marker development, and studies on signaling pathways in this species and will serve as a reference for the efficient use of other grasshoppers.