bluuebunny/crossref_metadata_2025 huggingface dataset:
Capturing Causality for Fault Diagnosis Based on Multi-Valued Alarm Series Using Transfer Entropy
Authors: Su Jianjun , Wang Dezheng , Zhang Yinong , Yang Fan , Zhao Yan , Pang Xiangkun
Published: December 2017

Transfer entropy (TE) is a model-free approach based on information theory to capture causality between variables, which has been used for the modeling and monitoring of, and fault diagnosis in, complex industrial processes. It is able to detect the causality between variables without assuming any underlying model, but it is computationally burdensome. To overcome this limitation, a hybrid method of TE and the modified conditional mutual information (CMI) approach is proposed by using generated multi-valued alarm series. In order to obtain a process topology, TE can generate a causal map of all sub-processes and modified CMI can be used to distinguish the direct connectivity from the above-mentioned causal map by using multi-valued alarm series. The effectiveness and accuracy rate of the proposed method are validated by simulated and real industrial cases (the Tennessee-Eastman process) to capture process topology by using multi-valued alarm series.
Reducing Approximation Error in the Fourier Flexible Functional Form
Authors: Skolrud Tristan
Published: December 2017

The Fourier Flexible form provides a global approximation to an unknown data generating process. In terms of limiting function specification error, this form is preferable to functional forms based on second-order Taylor series expansions. The Fourier Flexible form is a truncated Fourier series expansion appended to a second-order expansion in logarithms. By replacing the logarithmic expansion with a Box-Cox transformation, we show that the Fourier Flexible form can reduce approximation error by 25% on average in the tails of the data distribution. The new functional form allows for nested testing of a larger set of commonly implemented functional forms.
Day-Ahead Wind Power Forecasting Using a Two-Stage Hybrid Modeling Approach Based on SCADA and Meteorological Information, and Evaluating the Impact of Input-Data Dependency on Forecasting Accuracy
Authors: Zheng Dehua , Shi Min , Wang Yifeng , Eseye Abinet , Zhang Jianhua
Published: December 2017

The power generated by wind generators is usually associated with uncertainties, due to the intermittency of wind speed and other weather variables. This creates a big challenge for transmission system operators (TSOs) and distribution system operators (DSOs) in terms of connecting, controlling and managing power networks with high-penetration wind energy. Hence, in these power networks, accurate wind power forecasts are essential for their reliable and efficient operation. They support TSOs and DSOs in enhancing the control and management of the power network. In this paper, a novel two-stage hybrid approach based on the combination of the Hilbert-Huang transform (HHT), genetic algorithm (GA) and artificial neural network (ANN) is proposed for day-ahead wind power forecasting. The approach is composed of two stages. The first stage utilizes numerical weather prediction (NWP) meteorological information to predict wind speed at the exact site of the wind farm. The second stage maps actual wind speed vs. power characteristics recorded by SCADA. Then, the wind speed forecast in the first stage for the future day is fed to the second stage to predict the future day’s wind power. Comparative selection of input-data parameter sets for the forecasting model and impact analysis of input-data dependency on forecasting accuracy have also been studied. The proposed approach achieves significant forecasting accuracy improvement compared with three other artificial intelligence-based forecasting approaches and a benchmark model using the smart persistence method.
Global Feedback Control for Coordinated Linear Switched Reluctance Machines Network with Full-State Observation and Internal Model Compensation
Authors: Zhang Bo , Yuan Jianping , Pan J. F. , Wu Xiaoyu , Luo Jianjun , Qiu Li
Published: December 2017

This paper discusses the tracking coordination of a linear switched reluctance machine (LSRM) network based on a global feedback control strategy with a full-state observation framework. The observer is allocated on the follower instead of the leader to form a leader–follower–observer network, by utilizing the leader as the global feedback tracking controller and the observer as the observation of the full states. The internal model compensator (IMC) is applied to the leader for the improvement of the network performance. The full-state information of the LSRM network is reconfigured by the output of the LSRM where the observer is located to provide necessary feedback information to the leader. Then, the controllability and observability of the leader–follower–observer network with the IMC are inspected, serving as a basis for the design of the global controller with the IMC and full-state observer. Experimentation verifies the effectiveness of the proposed network control scheme and the results demonstrate that both the absolute and the relative accuracy can be simultaneously improved, compared to the LSRM network with only the consensus algorithm and no global feedback mechanism.
Coupled Model of Heat and Mass Balance for Droplet Growth in Wet Steam Non-Equilibrium Homogeneous Condensation Flow
Authors: Han Xu , Han Zhonghe , Zeng Wei , Qian Jiangbo , Wang Zhi
Published: December 2017

Because of the complexity of wet steam two-phase condensation flow, many problems remain to be solved. The important part of condensation theory—the calculation of the water droplet growth model in the transition zone—is not ideal; thus, it is necessary to develop a water droplet growth model with full-scale range. On the basis of the heat and mass transfer equilibrium in droplet growth, a coupled model of heat and mass balance for droplet growth is proposed. To verify the accuracy of this model, the differences and applicable ranges of various models were analysed using the experimental data of Peters and Meyer and two widely used models. In the free molecular flow region, the heat and mass balance model coincides with the Young low-pressure correction model. In the transition region, the heat and mass balance model agrees well with the experimental values of Peters and Meyer. In the continuous flow region, the heat and mass balance model coincides with the Gyarmathy model. Therefore, the heat and mass balance model can be used to accurately describe the growth process of water droplets in the arbitrary range of Knudsen numbers.
A Single-Phase Multilevel PV Generation System with an Improved Ripple Correlation Control MPPT Algorithm
Authors: Hammami Manel , Grandi Gabriele
Published: December 2017

The implementation of maximum power point tracking (MPPT) schemes by the ripple correlation control (RCC) algorithm is presented in this paper. A reference is made to single-phase single-stage multilevel photovoltaic (PV) generation systems, when the inverter input variables (PV voltage and PV current) have multiple low-frequency (ripple) harmonics. The harmonic analysis is carried out with reference to a multilevel configuration consisting of an H-bridge inverter and level doubling network (LDN) cell, leading to the multilevel inverter having double the output voltage levels as compared to the basic H-bridge inverter topology (i.e., five levels vs. three levels). The LDN cell is basically a half-bridge fed by a floating capacitor, with self-balancing voltage capability. The multilevel configuration introduces additional PV voltage and current low-frequency harmonics, perturbing the basic implementation of the RCC scheme (based on the second harmonic component), leading to malfunctioning. The proposed RCC algorithm employs the PV current and voltage harmonics at a specific frequency for the estimation of the voltage derivative of power dP/dV (or dI/dV), driving the PV operating point toward the maximum power point (MPP) in a faster and more precise manner. The steady-state and transient performances of the proposed RCC-MPPT schemes have been preliminarily tested and compared using MATLAB/Simulink. Results have been verified by experimental tests considering the whole multilevel PV generation system, including real PV modules, multilevel insulated-gate bipolar transistor (IGBT) inverters, and utility grids.
Biomass Chars: Elaboration, Characterization and Applications
Authors: Jeguirim Mejdi , Limousy Lionel
Published: December 2017

n/a
Performance Prediction of Centrifugal Compressor for Drop-In Testing Using Low Global Warming Potential Alternative Refrigerants and Performance Test Codes
Authors: Park Joo , Shin Youhwan , Chung Jin
Published: December 2017

As environmental regulations to stall global warming are strengthened around the world, studies using newly developed low global warming potential (GWP) alternative refrigerants are increasing. In this study, substitute refrigerants, R-1234ze (E) and R-1233zd (E), were used in the centrifugal compressor of an R-134a 2-stage centrifugal chiller with a fixed rotational speed. Performance predictions and thermodynamic analyses of the centrifugal compressor for drop-in testing were performed. A performance prediction method based on the existing ASME PTC-10 performance test code was proposed. The proposed method yielded the expected operating area and operating point of the centrifugal compressor with alternative refrigerants. The thermodynamic performance of the first and second stages of the centrifugal compressor was calculated as the polytropic state. To verify the suitability of the proposed method, the drop-in test results of the two alternative refrigerants were compared. The predicted operating range based on the permissible deviation of ASME PTC-10 confirmed that the temperature difference was very small at the same efficiency. Because the drop-in test of R-1234ze (E) was performed within the expected operating range, the centrifugal compressor using R-1234ze (E) is considered well predicted. However, the predictions of the operating point and operating range of R-1233zd (E) were lower than those of the drop-in test. The proposed performance prediction method will assist in understanding thermodynamic performance at the expected operating point and operating area of a centrifugal compressor using alternative gases based on limited design and structure information.
Unified Brake Service by a Hierarchical Controller for Active Deceleration Control in an Electric and Automated Vehicle
Authors: Nie Yuliang , Liu Yahui , Cheng Shuo , Mei Mingming , Xiao Lingyun
Published: December 2017

Unified brake service is a universal service for generating certain brake force to meet the demand deceleration and is essential for an automated driving system. However, it is rather difficult to control the pressure in the wheel cylinders to reach the target deceleration of the automated vehicle, which is the key issue of the active deceleration control system (ADC). This paper proposes a hierarchical control method to actively control vehicle deceleration with active-brake actuators. In the upper hierarchical, the target pressure of wheel cylinders is obtained by dynamic equations of a pure electric vehicle. In the lower hierarchical, the solenoid valve instructions and the pump speed of hydraulic control unit (HCU) are determined to satisfy the desired pressure with the feedback of measured wheel cylinder pressure by pressure sensors. Results of road experiments of a pure electric and automated vehicle indicate that the proposed method realizes the target deceleration accurately and efficiently.
Response of Runoff and Sediment on Skid Trails of Varying Gradient and Traffic Intensity over a Two-Year Period
Authors: Jourgholami Meghdad , Labelle Eric , Feghhi Jahangir
Published: December 2017

Compacted soil has lower water infiltration and hydraulic conductivity, which contributes to increased runoff and erosion on slopes. The aim of the present study was to assess runoff and sediment on three skidding trail longitudinal gradients (15%, 25%, and 35%) and different levels of machine traffic (low, medium, and high), over a two-year period following the impact in the Hyrcanian forest, Iran. The results show that trail gradient and traffic intensity have a significant effect on soil bulk density and total porosity on the skid trails. The average runoff amount varied significantly among trail gradients and ranged from 1.59 mm on the 15% trail gradient and 2.76 mm on the 25% trail gradient, to 4.76 mm on the 35% trail gradient in the low traffic intensity. Average sediment also increased significantly with increasing trail gradient. Average sediment was 0.01 kg m−2, 0.03 kg m−2, and 0.05 kg m−2 on the low traffic intensity in the first year for the 15%, 25%, and 35% trail gradients, respectively. The largest runoff and sediment occurred in the first year and stressed the need for applying forestry Best Management Practices such as the use of brush mats during harvesting operations, as well as the installation of water diversion structures or seeding immediately after initial soil compaction and disturbance, in order to protect the bare soil from heavy rainfall.
Aboveground Biomass Equations for Small Trees of Brutian Pine in Turkey to Facilitate Harvesting and Management
Authors: Eker Mehmet , Poudel Krishna P. , Özçelik Ramazan
Published: December 2017

Brutian pine (Pinus brutia Ten.) is the most widespread conifer species in the Eastern Mediterranean. Aboveground biomass equations for small diameter brutian pine trees are needed for accurate fuel inventory and to assess carbon sequestration potential. In this study, we developed tree biomass models based on 143 brutian pine saplings measured in 11 research plots. Aboveground biomass (AGB) was modeled with a nonlinear mixed effects model which accounted for the variability among plots. The predicted total AGB was then distributed into foliage, branch and stem components. The Beta, Dirichlet, and multinomial logistic regressions were unbiased in their estimates of biomass component proportions. The Dirichlet regression has the advantage of an additive property and does not require non-standard data.
Public-Goods Games with Endogenous Institution-Formation: Experimental Evidence on the Effect of the Voting Rule
Authors: Funaki Yukihiko , Li Jiawen , Veszteg Róbert
Published: December 2017

We report experimental results on voluntary contributions to public-goods provision from situations in which parties can create institutions to impose a certain contribution level on its members. We focus on a public-goods game where the joint decisions inside the institution are made based on the plurality voting rule. We show that, comparing to the unanimity voting rule, the plurality rule results in a significant and large decrease in the institution initiation rate, along with a significant and large increase in the institution implementation rate. In the end, as the two effects cancel each other out, the choice of the voting rule does not significantly affect the average contribution level or efficiency.
The Cost-Effectiveness of Lowering Permissible Noise Levels Around U.S. Airports
Authors: Jiao Boshen , Zafari Zafar , Will Brian , Ruggeri Kai , Li Shukai , Muennig Peter
Published: December 2017

Aircraft noise increases the risk of cardiovascular diseases and mental illness. The allowable limit for sound in the vicinity of an airport is 65 decibels (dB) averaged over a 24-h ‘day and night’ period (DNL) in the United States. We evaluate the trade-off between the cost and the health benefits of changing the regulatory DNL level from 65 dB to 55 dB using a Markov model. The study used LaGuardia Airport (LGA) as a case study. In compliance with 55 dB allowable limit of aircraft noise, sound insulation would be required for residential homes within the 55 dB to 65 dB DNL. A Markov model was built to assess the cost-effectiveness of installing sound insulation. One-way sensitivity analyses and Monte Carlo simulation were conducted to test uncertainty of the model. The incremental cost-effectiveness ratio of installing sound insulation for residents exposed to airplane noise from LGA was $11,163/QALY gained (95% credible interval: cost-saving and life-saving to $93,054/QALY gained). Changing the regulatory standard for noise exposure around airports from 65 dB to 55 dB comes at a very good value.
Nutrition Counselling Practices among General Practitioners in Croatia
Authors: Dumic Albina , Miskulin Ivan , Matic Licanin Matea , Mujkic Aida , Cacic Kenjeric Daniela , Miskulin Maja
Published: December 2017

Chronic non-communicable diseases are a significant public health problem and imbalanced nutrition is one of the most significant risk factor for them. The objective of this study was to examine Croatia’s general practitioners’ nutrition counselling practice and determine the factors that influence such practice. A cross-sectional study was conducted among 444 (17.0%) randomly selected general practitioners (GPs) in Croatia from May to July 2013 via a 32-item anonymous questionnaire. Study showed that 77.0% of participants had provided nutrition counselling exclusively to patients with specific health risks; 18.7% participants had provided nutrition counselling for all patients, regardless of their individual risks, while 4.3% had not provide nutrition counselling. As the most significant stimulating factor for implementing nutrition counselling in their daily work with patients, 55.6% of the participants identified personal interest regarding nutrition and the effects it has on health. The latter factor was more frequently emphasized among female general practitioners (p < 0.001) and general practitioners without chronic diseases (p < 0.001). The most significant barrier for nutrition counselling was lack of time (81.6%). It is necessary to make additional efforts to increase the frequency of nutrition counselling provided by general practitioners in Croatia. The majority of Croatian general practitioners could increase their nutrition counselling practice in order to promote balanced nutrition and improve the overall health status of their patients.
How Does Health-Related Advertising with a Regulatory Focus and Goal Framing Affect Attitudes toward Ads and Healthy Behavior Intentions?
Authors: Lin Chia-Yen , Yeh Wei-Ju
Published: December 2017

The health costs of colorectal cancer have increased over the years in Taiwan. The National Health Insurance Administration (NHI) and the Health Promotion Administration of the Ministry of Health and Welfare (MOHW) in Taiwan advocate that people have to change their unhealthy behaviors; however, the number of patients of colorectal cancer is increasing annually. This research discussed the effects of healthy diet advocacy advertisements (ads) on healthy diet behavior intentions as influenced by the interactions between regulatory focus theory (RFT) and message framing effects. Both regulatory focus theory and message framing effect were discussed for the relationship between advertisement and behavior change in many fields, such as health-related behavior, pro-environmental behavior, consumer choice, etc. We executed an experiment with four different types of public health advocacy ads. A 2 (regulatory focus: promotion vs. prevention) × 2 (message framing: gain framing vs. loss framing) two-factor experiment was adopted, and 201 valid participants responded to the questionnaire. Results indicated that if the ad’s regulatory focus is promotion focus, viewers’ attitudes toward the ad and their behavior intentions are more positive when the slogan of the ad is gain framing rather than loss framing via the multiple analysis of variance (MANOVA), and vice versa. Respondents found the communication easier to comprehend when the ads evoked the respondents’ regulatory focus and applied the appropriate message framing, thus improving the efficacy of health-related advertising. We offer suggestions regarding the future use of health-related advertising for the MOHW.
Study on Spatial Spillover Effects of Logistics Industry Development for Economic Growth in the Yangtze River Delta City Cluster Based on Spatial Durbin Model
Authors: Xu Xinxing , Wang Yuhong
Published: December 2017

The overall entropy method is used to evaluate the development level of the logistics industry in the city based on a mechanism analysis of the spillover effect of the development of the logistics industry on economic growth, according to the panel data of 26 cities in the Yangtze River delta. On this basis, the paper uses the spatial durbin model to study the direct impact of the development of the logistics industry on economic growth and the spatial spillover effect. The results show that the direct impact coefficient of the development of the logistics industry in the Yangtze River Delta urban agglomeration on local economic growth is 0.092, and the significant spatial spillover effect on the economic growth in the surrounding area is 0.197. Compared with the labor force input, capital investment and the degree of opening to the world, and government functions, the logistics industry’s direct impact coefficient is the largest, other than capital investment; the coefficient of the spillover effect is higher than other control variables, making it a “strong engine” of the Yangtze River Delta urban agglomeration economic growth.
Sulfur-Mediated-Alleviation of Aluminum-Toxicity in Citrus grandis Seedlings
Authors: Guo Peng , Li Qiang , Qi Yi-Ping , Yang Lin-Tong , Ye Xin , Chen Huan-Huan , Chen Li-Song
Published: December 2017

Limited data are available on the sulfur (S)-mediated-alleviation of aluminum (Al)-toxicity in higher plants. Citrus grandis seedlings were irrigated for 18 weeks with 0.5 mM MgSO4 or 0.5 mM MgSO4 + 0.5 mM Na2SO4, and 0 (−Al) or 1 mM AlCl3·6H2O (+Al, Al-toxicity). Under Al-toxicity, S decreased the level of Al in leaves; increased the relative water content (RWC) of roots and leaves, the contents of phosphorus (P), calcium (Ca) and magnesium (Mg) per plant, the dry weights (DW) of roots and shoots, the ratios of root DW/shoot DW, and the Al-induced secretion of citrate from root; and alleviated the Al-induced inhibition of photosynthesis via mitigating the Al-induced decrease of electron transport capacity resulting from the impaired photosynthetic electron transport chain. In addition to decreasing the Al-stimulated H2O2 production, the S-induced upregulation of both S metabolism-related enzymes and antioxidant enzymes also contributed to the S-mediated-alleviation of oxidative damage in Al-treated roots and leaves. Decreased transport of Al from roots to shoots and relatively little accumulation of Al in leaves, and increased leaf and root RWC and P, Ca, and Mg contents per plant might also play a role in the S-mediated-alleviation of Al-toxicity.
Diffuse Axonal Injury and Oxidative Stress: A Comprehensive Review
Authors: Frati Alessandro , Cerretani Daniela , Fiaschi Anna , Frati Paola , Gatto Vittorio , La Russa Raffaele , Pesce Alessandro , Pinchi Enrica , Santurro Alessandro , Fraschetti Flavia , Fineschi Vittorio
Published: December 2017

Traumatic brain injury (TBI) is one of the world’s leading causes of morbidity and mortality among young individuals. TBI applies powerful rotational and translational forces to the brain parenchyma, which results in a traumatic diffuse axonal injury (DAI) responsible for brain swelling and neuronal death. Following TBI, axonal degeneration has been identified as a progressive process that starts with disrupted axonal transport causing axonal swelling, followed by secondary axonal disconnection and Wallerian degeneration. These modifications in the axonal cytoskeleton interrupt the axoplasmic transport mechanisms, causing the gradual gathering of transport products so as to generate axonal swellings and modifications in neuronal homeostasis. Oxidative stress with consequent impairment of endogenous antioxidant defense mechanisms plays a significant role in the secondary events leading to neuronal death. Studies support the role of an altered axonal calcium homeostasis as a mechanism in the secondary damage of axon, and suggest that calcium channel blocker can alleviate the secondary damage, as well as other mechanisms implied in the secondary injury, and could be targeted as a candidate for therapeutic approaches. Reactive oxygen species (ROS)-mediated axonal degeneration is mainly caused by extracellular Ca2+. Increases in the defense mechanisms through the use of exogenous antioxidants may be neuroprotective, particularly if they are given within the neuroprotective time window. A promising potential therapeutic target for DAI is to directly address mitochondria-related injury or to modulate energetic axonal energy failure.
Glycoprotein 90K Promotes E-Cadherin Degradation in a Cell Density-Dependent Manner via Dissociation of E-Cadherin–p120-Catenin Complex
Authors: Park So-Yeon , Yoon Somy , Sun Eun , Zhou Rui , Bae Jeong , Seo Young-Woo , Chae Jung-Il , Paik Man-Jeong , Ha Hyung-Ho , Kim Hangun , Kim Kyung
Published: December 2017

Glycoprotein 90K (also known as LGALS3BP or Mac-2BP) is a tumor-associated protein, and high 90K levels are associated with poor prognosis in some cancers. To clarify the role of 90K as an indicator for poor prognosis and metastasis in epithelial cancers, the present study investigated the effect of 90K on an adherens junctional protein, E-cadherin, which is frequently absent or downregulated in human epithelial cancers. Treatment of certain cancer cells with 90K significantly reduced E-cadherin levels in a cell-population-dependent manner, and these cells showed decreases in cell adhesion and increases in invasive cell motility. Mechanistically, 90K-induced E-cadherin downregulation occurred via ubiquitination-mediated proteasomal degradation. 90K interacted with the E-cadherin–p120-catenin complex and induced its dissociation, altering the phosphorylation status of p120-catenin, whereas it did not associate with β-catenin. In subconfluent cells, 90K decreased membrane-localized p120-catenin and the membrane fraction of the p120-catenin. Particularly, 90K-induced E-cadherin downregulation was diminished in p120-catenin knocked-down cells. Taken together, 90K upregulation promotes the dissociation of the E-cadherin–p120-catenin complex, leading to E-cadherin proteasomal degradation, and thereby destabilizing adherens junctions in less confluent tumor cells. Our results provide a potential mechanism to explain the poor prognosis of cancer patients with high serum 90K levels.
Plasma Sphingolipids in Acute Pancreatitis
Authors: Konończuk Tomasz , Łukaszuk Bartłomiej , Żendzian-Piotrowska Małgorzata , Dąbrowski Andrzej , Krzyżak Michalina , Ostrowska Lucyna , Kurek Krzysztof
Published: December 2017

Acute pancreatitis (AP) is a prevalent gastrointestinal disorder associated with systemic inflammatory response syndrome and, in the case of severe AP, a mortality rate ranging from 36% to 50%. Standard clinical treatment of AP includes intensive hydration, analgesia, and management of complications. Unfortunately, the direct treatment of AP at the level of its molecular pathomechanism has not yet been established. Recent studies indicate that the sphingolipid signaling pathway may be one of the important factors contributing to the development of inflammation in pancreatic diseases. In the current study, we sought to investigate this promising route. We examined the plasma sphingolipid profile of 44 patients with acute pancreatitis, dividing them into three groups: mild, moderate and severe AP. Samples were collected from these groups at days 1, 3 and 7 following their hospital admission. We demonstrated significant changes in blood plasma sphingolipids in relation to the time course of AP. We also found an inhibition of de novo ceramide synthesis in mild and moderate AP. However, the most important and novel finding was a significant elevation in sphingosine-1-phosphate (S1P) (a downstream metabolite of ceramide) in mild AP, as well as a dramatic reduction in the lipid molecule content in the early stage (days 1 and 3) of severe AP. This strongly indicates that plasma S1P could serve as a prognostic marker of AP severity.
Molecular and Genetic Determinants of Glioma Cell Invasion
Authors: Masui Kenta , Kato Yoichiro , Sawada Tatsuo , Mischel Paul , Shibata Noriyuki
Published: December 2017

A diffusely invasive nature is a major obstacle in treating a malignant brain tumor, “diffuse glioma”, which prevents neurooncologists from surgically removing the tumor cells even in combination with chemotherapy and radiation. Recently updated classification of diffuse gliomas based on distinct genetic and epigenetic features has culminated in a multilayered diagnostic approach to combine histologic phenotypes and molecular genotypes in an integrated diagnosis. However, it is still a work in progress to decipher how the genetic aberrations contribute to the aggressive nature of gliomas including their highly invasive capacity. Here we depict a set of recent discoveries involving molecular genetic determinants of the infiltrating nature of glioma cells, especially focusing on genetic mutations in receptor tyrosine kinase pathways and metabolic reprogramming downstream of common cancer mutations. The specific biology of glioma cell invasion provides an opportunity to explore the genotype-phenotype correlation in cancer and develop novel glioma-specific therapeutic strategies for this devastating disease.
Efficient Generation of Somatic Cell Nuclear Transfer-Competent Porcine Cells with Mutated Alleles at Multiple Target Loci by Using CRISPR/Cas9 Combined with Targeted Toxin-Based Selection System
Authors: Sato Masahiro , Miyoshi Kazuchika , Nakamura Shingo , Ohtsuka Masato , Sakurai Takayuki , Watanabe Satoshi , Kawaguchi Hiroaki , Tanimoto Akihide
Published: December 2017

The recent advancement in genome editing such a CRISPR/Cas9 system has enabled isolation of cells with knocked multiple alleles through a one-step transfection. Somatic cell nuclear transfer (SCNT) has been frequently employed as one of the efficient tools for the production of genetically modified (GM) animals. To use GM cells as SCNT donor, efficient isolation of transfectants with mutations at multiple target loci is often required. The methods for the isolation of such GM cells largely rely on the use of drug selection-based approach using selectable genes; however, it is often difficult to isolate cells with mutations at multiple target loci. In this study, we used a novel approach for the efficient isolation of porcine cells with at least two target loci mutations by one-step introduction of CRISPR/Cas9-related components. A single guide (sg) RNA targeted to GGTA1 gene, involved in the synthesis of cell-surface α-Gal epitope (known as xenogenic antigen), is always a prerequisite. When the transfected cells were reacted with toxin-labeled BS-I-B4 isolectin for 2 h at 37 °C to eliminate α-Gal epitope-expressing cells, the surviving clones lacked α-Gal epitope expression and were highly expected to exhibit induced mutations at another target loci. Analysis of these α-Gal epitope-negative surviving cells demonstrated a 100% occurrence of genome editing at target loci. SCNT using these cells as donors resulted in the production of cloned blastocysts with the genotype similar to that of the donor cells used. Thus, this novel system will be useful for SCNT-mediated acquisition of GM cloned piglets, in which multiple target loci may be mutated.
Fixed and Adaptive Parallel Subgroup-Specific Design for Survival Outcomes: Power and Sample Size
Authors: Antoniou Miranta , Jorgensen Andrea L. , Kolamunnage-Dona Ruwanthi
Published: December 2017

Biomarker-guided clinical trial designs, which focus on testing the effectiveness of a biomarker-guided approach to treatment in improving patient health, have drawn considerable attention in the era of stratified medicine with many different designs being proposed in the literature. However, planning such trials to ensure they have sufficient power to test the relevant hypotheses can be challenging and the literature often lacks guidance in this regard. In this study, we focus on the parallel subgroup-specific design, which allows the evaluation of separate treatment effects in the biomarker-positive subgroup and biomarker-negative subgroup simultaneously. We also explore an adaptive version of the design, where an interim analysis is undertaken based on a fixed percentage of target events, with the option to stop each biomarker-defined subgroup early for futility or efficacy. We calculate the number of events and patients required to ensure sufficient power in each of the biomarker-defined subgroups under different scenarios when the primary outcome is time-to-event. For the adaptive version, stopping probabilities are also explored. Since multiple hypotheses are being tested simultaneously, and multiple interim analyses are undertaken, we also focus on controlling the overall type I error rate by way of multiplicity adjustment.
Enrichment of Circular Code Motifs in the Genes of the Yeast Saccharomyces cerevisiae
Authors: Michel Christian J. , Nguefack Ngoune Viviane , Poch Olivier , Ripp Raymond , Thompson Julie D.
Published: December 2017

A set

X

of 20 trinucleotides has been found to have the highest average occurrence in the reading frame, compared to the two shifted frames, of genes of bacteria, archaea, eukaryotes, plasmids and viruses. This set

X

has an interesting mathematical property, since

X

is a maximal

C

3

self-complementary trinucleotide circular code. Furthermore, any motif obtained from this circular code

X

has the capacity to retrieve, maintain and synchronize the original (reading) frame. Since 1996, the theory of circular codes in genes has mainly been developed by analysing the properties of the 20 trinucleotides of

X

, using combinatorics and statistical approaches. For the first time, we test this theory by analysing the

X

motifs, i.e., motifs from the circular code

X

, in the complete genome of the yeast Saccharomyces cerevisiae. Several properties of

X

motifs are identified by basic statistics (at the frequency level), and evaluated by comparison to

R

motifs, i.e., random motifs generated from 30 different random codes

R

. We first show that the frequency of

X

motifs is significantly greater than that of

R

motifs in the genome of S. cerevisiae. We then verify that no significant difference is observed between the frequencies of

X

and

R

motifs in the non-coding regions of S. cerevisiae, but that the occurrence number of

X

motifs is significantly higher than

R

motifs in the genes (protein-coding regions). This property is true for all cardinalities of

X

motifs (from 4 to 20) and for all 16 chromosomes. We further investigate the distribution of

X

motifs in the three frames of S. cerevisiae genes and show that they occur more frequently in the reading frame, regardless of their cardinality or their length. Finally, the ratio of

X

genes, i.e., genes with at least one

X

motif, to non-

X

genes, in the set of verified genes is significantly different to that observed in the set of putative or dubious genes with no experimental evidence. These results, taken together, represent the first evidence for a significant enrichment of

X

motifs in the genes of an extant organism. They raise two hypotheses: the

X

motifs may be evolutionary relics of the primitive codes used for translation, or they may continue to play a functional role in the complex processes of genome decoding and protein synthesis.
Co-Precipitation, Strength and Electrical Resistivity of Cu–26 wt % Ag–0.1 wt % Fe Alloy
Authors: Li Rui , Wang Engang , Zuo Xiaowei
Published: December 2017

Both a Cu–26 wt % Ag (Fe-free) alloy and Cu–26 wt % Ag–0.1 wt % Fe (Fe-doping) alloy were subjected to different heat treatments. We studied the precipitation kinetics of Ag and Cu, microstructure evolution, magnetization, hardness, strength, and electrical resistivity of the two alloys. Fe addition was incapable of changing the precipitation kinetics of Ag and Cu; however, it decreased the size and spacing of rod-shaped Ag precipitates within a Cu matrix, because Fe might affect the elastic strain field and diffusion field, suppressing the nucleation of Ag precipitates. Magnetization curves showed that γ-Fe precipitates were precipitated out of the Cu matrix, along with Ag precipitates in Fe-doping alloy after heat treatments. The yield strength of the Fe-doping alloy was higher than that of the Fe-free alloy, and the maximum increment was about 41.3%. The electrical conductivity in the aged Fe-doping alloy was up to about 67% IACS (International Annealed Copper Standard). Hardness, strength, and electrical resistivity were intensively discussed, based on the microstructural characterization and solute contributions of both alloys. Our results demonstrated that an increasing fraction of nanoscale γ-Fe precipitates and decreasing spacing between Ag precipitates resulted in the increasing strength of the Fe-doping alloy.
The Osteogenic and Tenogenic Differentiation Potential of C3H10T1/2 (Mesenchymal Stem Cell Model) Cultured on PCL/PLA Electrospun Scaffolds in the Absence of Specific Differentiation Medium
Authors: Baudequin Timothée , Gaut Ludovic , Mueller Marc , Huepkes Angela , Glasmacher Birgit , Duprez Delphine , Bedoui Fahmi , Legallais Cécile
Published: December 2017

The differentiation potential of mesenchymal stem cells (MSC) has been extensively tested on electrospun scaffolds. However, this potential is often assessed with lineage-specific medium, making it difficult to interpret the real contribution of the properties of the scaffold in the cell response. In this study, we analyzed the ability of different polycaprolactone/polylactic acid PCL/PLA electrospun scaffolds (pure or blended compositions, random or aligned fibers, various fiber diameters) to drive MSC towards bone or tendon lineages in the absence of specific differentiation medium. C3H10T1/2 cells (a mesenchymal stem cell model) were cultured on scaffolds for 96 h without differentiation factors. We performed a cross-analysis of the cell–scaffold interactions (spreading, organization, and specific gene expression) with mechanical (elasticity), morphological (porosity, fibers diameter and orientation) and surface (wettability) characterizations of the electrospun fibers. We concluded that (1) osteogenic differentiation can be initiated on pure PCL-based electrospun scaffolds without specific culture conditions; (2) fiber alignment modified cell organization in the short term and (3) PLA added to PCL with an increased fiber diameter encouraged the stem cells towards the tendon lineage without additional tenogenic factors. In summary, the differentiation potential of stem cells on adapted electrospun fibers could be achieved in factor-free medium, making possible future applications in clinically relevant situations.
Extraction of Palladium(II) from Hydrochloric Acid Solutions by Solvent Extraction with Mixtures Containing Either Cyanex 301 or LIX 63
Authors: Truong Hoai , Lee Man , Son Seong
Published: December 2017

Cyanex 301 and 5,8-diethyl-7-hydroxyldodecane-6-oxime (LIX 63) can selectively extract Pd(II) over Pt(IV) from concentrated hydrochloric acid solutions. Therefore, solvent extraction experiments have been performed by extractant mixtures containing either Cyanex 301 or LIX 63, and the extraction behavior of Pd(II) was compared. Among the mixtures of Cyanex 301, the highest synergistic enhancement coefficient was achieved by mixing Cyanex 301 and trioctylphosphine oxide (TOPO). However, it was very difficult to strip the Pd(II) from the loaded mixture phase. Among the mixtures of LIX 63, the mixture of LIX 63 and alamine 336/TOPO enhanced the extraction of Pd(II). Although the synergistic coefficient by Cyanex 301 + TOPO was higher than that by LIX 63 + Alamine 336, the Pd(II) in the loaded mixture phase of LIX 63 and alamine 336 was easily stripped by thiourea.
Discovery of a Novel Cationic Surfactant: Tributyltetradecyl-Phosphonium Chloride for Iron Ore Flotation: From Prediction to Experimental Verification
Authors: Chen Pan , Hu Yuehua , Gao Zhiyong , Zhai Jihua , Fang Dong , Yue Tong , Zhang Chenyang , Sun Wei
Published: December 2017

In this work, tributyltetradecyl-phosphonium chloride (TTPC), has been first introduced to be a novel and efficient cationic surfactant for cationic reverse flotation separation of quartz from magnetite. The first-principles density functional theory calculations, Zeta potential measurements and adsorption isotherm measurements consistently predict that TTPC may be a promising collector that is better than dodecyl triethyl ammonium chloride (DTAC), based on the facts that TTPC and DTAC both prefer to physically adsorb on the quartz surface owing to electrostatic force, but the active part (P+(C4H9)3) of TTPC takes much more positive charges than that (N+(CH3)3) of DTAC. The micro-flotation and Bench-scale flotation results further verify that TTPC presents a stronger collecting power and much better selectivity for iron ore reverse flotation in comparison to the conventional collector DTAC. Furthermore, the corresponding adsorption mechanism of TTPC on the quartz have also been investigated in detail. This work might show a good example to discover a potential candidate collector by analogy with a known excellent collector based on reasonable prediction.
Evaluation of Poly(Lactic-co-glycolic) Acid Alone or in Combination with Hydroxyapatite on Human-Periosteal Cells Bone Differentiation and in Sinus Lift Treatment
Authors: Ceccarelli Gabriele , Presta Rossella , Lupi Saturnino , Giarratana Nefele , Bloise Nora , Benedetti Laura , Cusella De Angelis Maria , Rodriguez y Baena Ruggero
Published: December 2017

Most recent advances in tissue engineering in the fields of oral surgery and dentistry have aimed to restore hard and soft tissues. Further improvement of these therapies may involve more biological approaches and the use of dental tissue stem cells in combination with inorganic/organic scaffolds. In this study, we analyzed the osteoconductivity of two different inorganic scaffolds based on poly (lactic-co-glycolic) acid alone (PLGA-Fisiograft) or in combination with hydroxyapatite (PLGA/HA-Alos) in comparison with an organic material based on equine collagen (PARASORB Sombrero) both in vitro and in vivo. We developed a simple in vitro model in which periosteum-derived stem cells were grown in contact with chips of these scaffolds to mimic bone mineralization. The viability of cells and material osteoconductivity were evaluated by osteogenic gene expression and histological analyses at different time points. In addition, the capacity of scaffolds to improve bone healing in sinus lift was examined. Our results demonstrated that the osteoconductivity of PLGA/HA-Alos and the efficacy of scaffolds in promoting bone healing in the sinus lift were increased. Thus, new clinical approaches in sinus lift follow-up should be considered to elucidate the clinical potential of these two PLGA-based materials in dentistry.
A Diastereoselective Synthesis of Dispiro[oxindole-cyclohexanone]pyrrolidines by 1,3-Dipolar Cycloaddition
Authors: Anis’kov Alexander , Klochkova Irina , Tumskiy Roman , Yegorova Alevtina
Published: December 2017

For the first time, arylmethylidene cyclohexanones that are non-symmetrical due to the presence of peripheral substituents were studied in 1,3-dipolar cycloaddition reactions. It is shown that the interaction with the azomethine ylide generated from sarcosine proceeds regio- and diastereoselectively, with the participation of two non-equivalent parts of the dipolarophile. Also for the first time, β-amino ketones (Mannich bases) were used as dipolarophile equivalents of unsaturated ketones. It was found that cycloaddition occurs diastereoselectively at the generated center.
Monitoring the Activity of Immobilized Lipase with Quinizarin Diester Fluoro-Chromogenic Probe
Authors: Aparecida Sabatini Carolina , Massucatto dos Santos Denis , Matos de Oliveira da Silva Sabrina , Henrique Gehlen Marcelo
Published: December 2017

Quinizarin diester is used as a fluoro-chromogenic substrate of the activity of lipase supported in poly(methylmetacrylate) beads (CALB, Novozym® 435) dispersed in organic solvents. The monoester and diester of quinizarin are both non-fluorescent species contrasting with the enzymatic product quinizarin that shows optical absorption in the visible region and strong fluorescence signal. The enzymatic conversion is accomplished by spectroscopic measurements and it follows a sigmoid curve from which the mean reaction time of the enzymatic process can be determined. This parameter indicates the enzyme activity of the immobilized lipase. Its dependency with the amount of lipase allowed the determination of the ratio of the catalytic rate and the Michaelis constant (kc/Km) and the experimental value found was (1.0 ± 0.1) × 10−2 mg−1/min in the case of quinizarin diacetate.
Plants of the Genus Zingiber as a Source of Bioactive Phytochemicals: From Tradition to Pharmacy
Authors: Sharifi-Rad Mehdi , Varoni Elena Maria , Salehi Bahare , Sharifi-Rad Javad , Matthews Karl R. , Ayatollahi Seyed Abdulmajid , Kobarfard Farzad , Ibrahim Salam A. , Mnayer Dima , Zakaria Zainul Amiruddin , Sharifi-Rad Majid , Yousaf Zubaida , Iriti Marcello , Basile Adriana , Rigano Daniela
Published: December 2017

Plants of the genus Zingiber (Family Zingiberaceae) are widely used throughout the world as food and medicinal plants. They represent very popular herbal remedies in various traditional healing systems; in particular, rhizome of Zingiber spp. plants has a long history of ethnobotanical uses because of a plethora of curative properties. Antimicrobial activity of rhizome essential oil has been extensively confirmed in vitro and attributed to its chemical components, mainly consisting of monoterpene and sesquiterpene hydrocarbons such as α-zingiberene, ar-curcumene, β-bisabolene and β-sesquiphellandrene. In addition, gingerols have been identified as the major active components in the fresh rhizome, whereas shogaols, dehydrated gingerol derivatives, are the predominant pungent constituents in dried rhizome. Zingiber spp. may thus represent a promising and innovative source of natural alternatives to chemical food preservatives. This approach would meet the increasing concern of consumers aware of the potential health risks associated with the conventional antimicrobial agents in food. This narrative review aims at providing a literature overview on Zingiber spp. plants, their cultivation, traditional uses, phytochemical constituents and biological activities.
Cationic Biomimetic Particles of Polystyrene/Cationic Bilayer/Gramicidin for Optimal Bactericidal Activity
Authors: Xavier Gabriel R. S. , Carmona-Ribeiro Ana M.
Published: December 2017

Nanostructured particles of polystyrene sulfate (PSS) covered by a cationic lipid bilayer of dioctadecyldimethylammonium bromide (DODAB) incorporated gramicidin D (Gr) yielding optimal and broadened bactericidal activity against both Escherichia coli and Staphylococcus aureus. The adsorption of DODAB/Gr bilayer onto PSS nanoparticles (NPs) increased the zeta-average diameter by 8–10 nm, changed the zeta-potential of the NPs from negative to positive, and yielded a narrow size distributions for the PSS/DODAB/Gr NPs, which displayed broad and maximal microbicidal activity at very small concentrations of the antimicrobials, namely, 0.057 and 0.0057 mM DODAB and Gr, respectively. The results emphasized the advantages of highly-organized, nanostructured, and cationic particles to achieve hybrid combinations of antimicrobials with broad spectrum activity at considerably reduced DODAB and Gr concentrations.