bluuebunny/crossref_metadata_2025 huggingface dataset:
Ishophloroglucin A, a Novel Phlorotannin for Standardizing the Anti-α-Glucosidase Activity of Ishige okamurae
Authors: Ryu BoMi , Jiang Yunfei , Kim Hyun-Soo , Hyun Jee-Min , Lim Sang-Bin , Li Yong , Jeon You-Jin
Published: November 2018

Nutraceutical use of algae requires understanding of the diversity and significance of their active compositions for intended activities. Ishige okamurae (I. okamurae) extract is well-known to possess α-glucosidase inhibitory activity; however, studies are needed to investigate its active composition in order to standardize its α-glucosidase inhibitory activity. In this study, we observed the intensity of the dominant compounds of each I. okamurae extract harvested between 2016 and 2017, and the different potency of each I. okamurae extract against α-glucosidase. By comparing the anti-α-glucosidase ability of the dominant compounds, a novel Ishophloroglucin A with highest α-glucosidase inhibitory activity was identified and suggested for standardization of anti-α-glucosidase activity in I. okamurae extract. Additionally, a validated analytical method for measurement of Ishophloroglucin A for future standardization of I. okamurae extract was established in this study. We suggest using Ishophloroglucin A to standardize anti-α-glucosidase potency of I. okamurae and propose the significance of standardization based on their composition for effective use of algae as marine-derived nutraceuticals.
Anti-MRSA Sesquiterpenes from the Semi-Mangrove Plant Myoporum bontioides A. Gray
Authors: Dong Li-Mei , Huang Li-Lan , Dai Hang , Xu Qiao-Lin , Ouyang Jin-Kui , Jia Xu-Chao , Gu Wen-Xiang , Tan Jian-Wen
Published: November 2018

The striking rise of methicillin-resistant Staphylococcus aureus (MRSA) infections has become a serious threat to public health worldwide. In an effort to search for new anti-MRSA agents from natural products, a bioassay-guided phytochemical study was conducted on the semi-mangrove plant Myoporum bontioides A. Gray, which led to the isolation of two new sesquiterpene alkaloids (1 and 2) and six known furanosesquiterpenes (3–8). Their structures were elucidated on the basis of extensive analysis of their 1D, 2D NMR and mass spectroscopic data. These two new alkaloids (1 and 2) displayed potent anti-MRSA activity with MIC value of 6.25 μg/mL. This is the first report of sesquiterpene alkaloids from the plants of Myoporum genus and their anti-MRSA activity.
Folate Receptor-Targeted and GSH-Responsive Carboxymethyl Chitosan Nanoparticles Containing Covalently Entrapped 6-Mercaptopurine for Enhanced Intracellular Drug Delivery in Leukemia
Authors: Wei Xuan , Liao Jianhong , Davoudi Zahra , Zheng Hua , Chen Jingru , Li Dan , Xiong Xiong , Yin Yihua , Yu Xiuxiang , Xiong Jinghui , Wang Qun
Published: November 2018

For enhanced intracellular accumulation of 6-mercaptopurine (6-MP) in leukemia, a folate receptor-targeted and glutathione (GSH)-responsive polymeric prodrug nanoparticle was made. The nanoparticles were prepared by conjugating 6-MP to carboxymethyl chitosan via a GSH-sensitive carbonyl vinyl sulfide linkage, ultrasonic self-assembly and surface decoration with folate. The TEM graphs shows that the as-synthesized nanoparticles are spherical with a particle size of 170~220 nm. In vitro drug release of nanoparticles demonstrated acceptable stability in PBS containing 20 μM GSH at pH 7.4. However, the cumulative drug release rate of the samples containing 20 mM and 10 mM GSH medium reached 78.9% and 64.8%, respectively, in pH 5.0 at 20 h. This indicated that this nano-sized system is highly sensitive to GSH. The inhibition ratio of folate-modified nanoparticles compared to unmodified nanoparticles was higher in cancer cells (human promyelocytic leukemia cells, HL-60) while their cytotoxicity was lower in normal cells (mouse fibroblast cell lines, L929). Furthermore, in vitro cancer cell incubation studies confirmed that folate-modified nanoparticles therapeutics were significantly more effective than unmodified nanoparticles therapeutics. Our results suggest that folate receptor-targeting and GSH-stimulation can significantly elevate tumour intracellular drug release. Therefore, folate-modified nanoparticles containing chemoradiotherapy is a potential treatment for leukemia therapy.
The Impact of Pt Concentration on Crystal Growth Mechanism in Pt-Pd Binary Alloy System in the Context of Molecular Dynamics
Authors: Kizilagac Servet , Celik Fatih Ahmet , Koksal Koray
Published: November 2018

This work aims to investigate the effect of Pt concentration on the crystal growth mechanism of a Platinum-Palladium (Pt-Pd) binary alloy system during the annealing process; starting from the amorphous phase to some definite temperatures. The calculations have been performed by using molecular dynamic (MD) simulations. Interatomic interactions are described by the Sutton-Chen type Embedded Atom Potential Energy function. In order to understand the main structural properties at the stable and unstable phases; changes in radial distribution function (RDF) curves versus time have been analyzed for different annealing temperatures. Crystalline type bonded pairs have been determined using MD calculations which is required for the computation of Avrami coefficients and for understanding crystal growth mechanism. The results demonstrate that the increase in concentration of Pt during annealing leads to migration of atoms in the crystal lattice points; elimination of dislocations and formation of perfect crystal structure.
A Modified Kulka Micromethod for the Rapid and Safe Analysis of Fructose and 1-Deoxy-d-xylulose-5-phosphate
Authors: Shaw Shreya , Ghosh Robin
Published: November 2018

The Kulka resorcinol assay (Kulka, R.G., Biochemistry 1956, 63, 542–548) for ketoses has been widely used in the literature but suffers from two major disadvantages: (a) it employs large amounts of potentially harmful reagents for a general biology laboratory environment; and (b) in its original formulation, it is unsuited for modern high-throughput applications. Here, we have developed a modified Kulka assay, which contains a safer formulation, employing approx. 5.4 M HCl in 250 µL aliquots, and is suitable for use in high-throughput systems biology or enzymatic applications. The modified assay has been tested extensively for the measurement of two ketoses—fructose (a common substrate in cell growth experiments) and 1-deoxy-d-xylulose-5-phosphate (DXP), the product of the DXP-synthase reaction—which until now has only been assayable using time-consuming chromatographic methods or radioactivity. The Kulka microassay has a sensitivity of 0–250 nmol fructose or 0–500 nmol DXP. The assay is suitable for monitoring the consumption of fructose in bacterial growth experiments but is too insensitive to be used directly for the measurement of DXP in in vitro enzyme assays. However, we show that after concentration of the DXP-enzyme mix by butanol extraction, the Kulka resorcinol method can be used for enzyme assays.
Mixed-Phase MnO2/N-Containing Graphene Composites Applied as Electrode Active Materials for Flexible Asymmetric Solid-State Supercapacitors
Authors: Chiu Hsin-Ya , Cho Chun-Pei
Published: November 2018

MnO2/N-containing graphene composites with various contents of Mn were fabricated and used as active materials for the electrodes of flexible solid-state asymmetric supercapacitors. By scanning electron microscopes (SEM), transmission electron microscope (TEM), energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectrometer (XPS), fourier-transform infrared spectroscopy (FTIR) and Raman spectra, the presence of MnO2 and N-containing graphene was verified. The MnO2 nanostructures decorated on the N-containing graphene were of α- and γ-mixed phases. N-containing graphene was found to reduce the charge transfer impedance in the high-frequency region at the electrode/electrolyte interface (RCT) due to its good conductivity. The co-existence of MnO2 and N-containing graphene led to a more reduced RCT and improved charge transfer. Both the mass loading and content of Mn in an active material electrode were crucial. Excess Mn caused reduced contacts between the electrode and electrolyte ions, leading to increased RCT, and suppressed ionic diffusion. When the optimized mass loading and Mn content were used, the 3-NGM1 electrode exhibiting the smallest RCT and a lower ionic diffusion impedance was obtained. It also showed a high specific capacitance of 638 F·g−1 by calculation from the cyclic voltammetry (CV) curves. The corresponding energy and power densities were 372.7 Wh·kg−1 and 4731.1 W·kg−1, respectively. The superior capacitance property arising from the synergistic effect of mixed-phase MnO2 and N-containing graphene had permitted the composites promising active materials for flexible solid-state asymmetric supercapacitors. Moreover, the increase of specific capacitance was found to be more significant by the pseudocapacitive MnO2 than N-containing graphene.
Chitosan-MgO Nanocomposite: One Pot Preparation and Its Utility as an Ecofriendly Biocatalyst in the Synthesis of Thiazoles and [1,3,4]thiadiazoles
Authors: Riyadh Sayed M. , Khalil Khaled D. , Aljuhani Ateyatallah
Published: November 2018

A chitosan-MgO hybrid nanocomposite was prepared using a simple chemical precipitation method and characterized using Fourier transform spectroscopy (FTIR), elemental analysis (EDX), and scanning electron microscopy (SEM). The nanocomposite was served as a powerful ecofriendly basic catalyst under microwave irradiation in the synthesis of two novel series of 5-arylazo-2-hydrazonothiazoles 4a–j and 2-hydrazono[1,3,4]thiadiazoles 8a–d, incorporating a sulfonamide group. The structures of the synthesized products were elucidated by spectral data and elemental analyses. Also, their yield percentages were calculated using triethylamine (as a traditional catalyst) and chitosan-MgO nanocomposite (as a green recyclable catalyst) in a comparative study.
The Natural Philosophy of Experiencing
Authors: Prentner Robert
Published: November 2018

A new philosophy of nature is urgently needed. The received ontological view, physicalism, is unable to account for experiential phenomena and in particular for consciousness in all its varieties. We shall outline the concept of experiencing which should figure as a new conceptual primitive in natural philosophy. Experiencing refers to a process which comprises the interaction of an agent with its world through action based on phenomenal experience. This process can be viewed under two different aspects. One regards the subjective aspect of experiencing, the other one regards it in terms of physical objects. The first case illustrates the “what-it-is-likeness” of experiencing, the second illustrates how experiencing gets “objectified” in nature. We furthermore wish to delineate our concept of experiencing from the concept of (meta-cognitive) awareness. Scientific theories that explain how awareness comes about in sufficiently organized brains should respect the distinction between experiencing and awareness. We also sketch how experiencing could be related to theoretical biology in terms of information processing by organisms. Experiencing is non-exclusive; it refers to a primitive and a-personal natural process and not to a property possessed only by humans or other persons.
Surface Plasmon Resonances in Silver Nanostars
Authors: Reyes Gómez Faustino , Rubira Rafael J. G. , Camacho Sabrina A. , Martin Cibely S. , Da Silva Robson R. , Constantino Carlos J. L. , Alessio Priscila , Oliveira Osvaldo N. , Mejía-Salazar J. Ricardo
Published: November 2018

The recent development of silver nanostars (Ag-NSs) is promising for improved surface-enhanced sensing and spectroscopy, which may be further exploited if the mechanisms behind the excitation of localized surface plasmon resonances (LSPRs) are identified. Here, we show that LSPRs in Ag-NSs can be obtained with finite-difference time-domain (FDTD) calculations by considering the nanostars as combination of crossed nanorods (Ag-NRs). In particular, we demonstrate that an apparent tail at large wavelengths ( λ ≳ 700 nm) observed in the extinction spectra of Ag-NSs is due to a strong dipolar plasmon resonance, with no need to invoke heterogeneity (different number of arms) effects as is normally done in the literature. Our description also indicates a way to tune the strongest LSPR at desired wavelengths, which is useful for sensing applications.
Fast and Reliable Determination of Virgin Olive Oil Quality by Fruit Inspection Using Computer Vision
Authors: Navarro Soto Javiera , Satorres Martínez Silvia , Martínez Gila Diego , Gómez Ortega Juan , Gámez García Javier
Published: November 2018

The presence of minor compounds in virgin olive oils has been proven to play multiple positive roles in health protection, encouraging its production. The key factors that influence the oil quality are ripening stages and the state of health of the fruit. For this reason, at the oil mill’s reception yard, fruits are visually inspected and separated according to their external appearance. In this way, the process parameters can be better adjusted to improve the quantity and/or quality of olive oil. This paper presents a proposal to automatically determine the oil quality before being produced from a previous inspection of the incoming fruits. Expert assessment of the fruit conditions guided the image processing. The proposal has been validated through the analysis of 74 batches of olives coming from an oil mill. Best correlation results between the image processing and the analytical data were found in the acidity index, peroxide values, ethyl ester, polyphenols, chlorophylls, and carotenoids.
Augmentation of GNSS by Low-Cost MEMS IMU, OBD-II, and Digital Altimeter for Improved Positioning in Urban Area
Authors: Lim JoonHoo , Yoo Won Jae , Kim La Woo , Lee You Dam , Lee Hyung Keun
Published: November 2018

This paper proposes an efficient multi-sensor system to complement GNSS (Global Navigation Satellite System) for improved positioning in urban area. The proposed system augments GNSS by low-cost MEMS IMU (Micro Electro Mechanical Systems Inertial Measurement Unit), OBD (On-Board Diagnostics)-II, and digital altimeter modules. For improved availability of time synchronization in urban area, an adaptive synchronization method is proposed to combine the external PPS (Pulse Per Second) signal and the internal onboard clock. For improved positioning accuracy and availability, a 17-state Kalman filter is formulated for efficient multi-sensor fusion, including OBD-II and digital altimeter modules. A strategy to apply different types of measurement updates is also proposed for improved performance in urban area. Four experiment results with field-collected measurements evaluates the performance of the proposed GNSS/IMU/OBD-II/altimeter system in various aspects, including accuracy, precision, continuity, and availability.
Quelques mécanismes chimiques du creusement des cavernes (plus particulièrement pour l'étude de la zone épinoyée)
Authors: Lismonde Baudouin
Published: November 2018

Les facteurs principaux qui commandent l'équilibre chimique des systèmes eau-air-calcaire sont la pression de l'air, la pression partielle de CO2 équilibrante et la température.

Les conditions aux limites de l'équilibre dans un système de laboratoire (fermé thermodynamiquement) et dans les systèmes karstiques (ouverts) sont ici analysées. La quantité limitée d'air atmosphérique au contact de l'eau est prise en compte par deux coefficients, dits de confinement qui représentent respectivement le rapport entre la masse d'eau et la masse totale air + eau (k), et le rapport entre la masse de CO2 dans l'eau et la masse totale de CO2 dans l'eau et Fair (kn) ; ce dernier coefficient variant avec la pression tout en restant proportionnel à la pression de CO2 équilibrante. L'influence de ces facteurs sur la spéléogenèse est ensuite abordée : le rôle de la pression de CO2 équilibrante, la température de l'eau, le mélange des eaux... L'observation fréquente de l'étagement des réseaux de montagne est souvent associée à l'idée d'une plus grande facilité de creusement chimique des cavités au voisinage du niveau piézométrique de l'eau. Le mécanisme proposé de l'agressivité plus grande de l'eau dans cette zone repose sur les mises en pression de l'air piégé et l'augmentation résultante de la pression de CO2 équilibrante de l'eau.
Geographic Variation in Surgical Practice Patterns and Outcomes for Resected Nonmetastatic Gastric Cancer in Ontario
Authors: Mahar A.L. , El-Sedfy A. , Dixon M. , Siddiqui M. , Elmi M. , Ritter A. , Vasilevska-Ristovska J. , Jeong Y. , Helyer L. , Law C. , Zagorski B. , Coburn N.G.
Published: November 2018

Background: Gastrectomy with negative resection margins and adequate lymph node dissection is the cornerstone of curative treatment for gastric cancer (GC). However, gastrectomy is a complex and invasive operation with significant morbidity and mortality. Little is known about surgical practice patterns or short- and long-term outcomes in earlystage GC in Canada. Methods: We undertook a population-based retrospective cohort study of patients with GC diagnosed between 1 April 2005 and 31 March 2008. Chart review provided clinical and operative details such as disease stage, primary tumour location, surgical approach, operation, lymph nodes, and resection margins. Administrative data provided patient demographics, geography, and vital status. Variations in treatment and outcomes were compared for 14 local health integration networks. Descriptive statistics and log-rank tests were used to examine geographic variation. Results: We identified 722 patients with nonmetastatic resected GC. We documented significant provincial variation in case mix, including primary tumour location, stage at diagnosis, and tumour grade. Short-term surgical outcomes varied across the province. The percentage of patients with 15 or fewer lymph nodes removed and examined varied from 41.8% to 73.8% (p = 0.02), and the rate of positive surgical margins ranged from 15.2% to 50.0% (p = 0.002). The 30-day surgical mortality rates did not vary statistically significantly across the province (p = 0.13); however, rates ranged from 0% to 16.7%. Overall 5-year survival was 44% and ranged from 31% to 55% across the province. Conclusions: This cohort of patients with resected stages I–III GC is the largest analyzed in Canada, providing important historical information about treatment outcomes. Understanding the causes of regional variation will support interventions aiming to improve GC operative outcomes in the cancer system.
Radiation Therapy and Immunotherapy—A Potential Combination in Cancer Treatment
Authors: Asna N. , Livoff A. , Batash R. , Debbi R. , Schaffer P. , Rivkind T. , Schaffer M.
Published: November 2018

Background: Radiation therapy (RT) is a longstanding treatment modality for cancer. In addition, immune checkpoint blockade has been a significant development in the field of immunotherapy, modifying key immunosuppressive pathways of cancer cells. Methods: The aim of the present work was to review current concepts of RT and immunotherapy synergism, the abscopal effect, and the molecular effects of RT in the tumour microenvironment, its influence on immune stimulation, and potential clinical outcomes that might evolve from ongoing studies. We also discuss potential predictors of clinical response. Results: Up-to-date literature concerning the mechanisms, interactions, and latest knowledge about RT and immunotherapy was reviewed and summarized, and is presented here. Conclusions: The possibility of using hyperfractionated RT to combine an abscopal effect with the enhanced effect of immune treatment using checkpoint blockade is a very promising method for future tumour treatments.
Evaluation of Subcutaneous Rituximab Administration on Canadian Systemic Therapy Suites
Authors: Stewart D.A. , Boudreault J.S. , Maturi B. , Boras D. , Foley R.
Published: November 2018

Background: Non-Hodgkin lymphoma (NHL) is the most common hematologic malignancy. Diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL) constitute 55% of new nhl cases and are initially treated with rituximab-based chemoimmunotherapy. Relative to intravenous (IV) rituximab, a subcutaneous (SC) formulation approved in 2016 has comparable pharmacokinetics, efficacy, and safety, and a greatly reduced administration time; it is also preferred by patients. The objective of the present study was to estimate the effect (on systemic therapy suite time and on the costs of drug acquisition and administration) of implementing SC rituximab in the initial chemoimmunotherapy for FL and DLBCL over 3 years in the Canadian market. Methods: An Excel (Microsoft Corporation, Redmond, WA, U.S.A.)–based model was created with a population size based on epidemiologic data and current rituximab use, duration of use considering initial therapy, time savings for SC rituximab administration from published studies, costs from standard Canadian sources, and assumed uptake in implementing provinces of 65%, 75%, and 80% over 3 years. Key parameters and sensitivity analysis values were validated by clinical experts located in various Canadian jurisdictions. Costs are reported in 2017 Canadian dollars from the perspective of the health care system. Results: More than 3 years after implementation of SC rituximab, we estimated that 5762 Canadians would be receiving SC rituximab, resulting in savings of 128,715 hours in systemic therapy suite time and approximately $40 million in drug and administration costs. Sensitivity analyses suggest that the model is most sensitive to SC market uptake, number of induction therapy cycles, and eligible patients. Conclusions: Subcutaneous administration of rituximab can significantly reduce systemic therapy suite time and achieve substantial savings in drug and administration costs.
Oxidative and reductive cyclization in stiff dithienylethenes
Authors: Kleinwächter Michael , Teichmann Ellen , Grubert Lutz , Herder Martin , Hecht Stefan
Published: November 2018

The electrochemical behavior of stiff dithienylethenes, undergoing double bond isomerization in addition to ring-closure, has been investigated. Electrochromism was observed in almost all cases, with the major pathway being the oxidatively induced cyclization of the open isomers. The influence of the ring size (to lock the reactive antiparallel conformation) as well as substituents (to modulate the redox potential) on the electrocyclization was examined. In the series of derivatives with 6-membered rings, both the E- and the Z-isomer convert to the closed isomer, whereas for the 7-membered rings no cyclization from the E-isomer was observed. For both stiff and normal dithienylethenes bearing benzonitrile substituents an additional and rare reductive electrocyclization was observed. The mechanism underlying both observed electrocyclization pathways has been elucidated.
Does Nonaxisymmetric Dynamo Operate in the Sun?
Authors: Pipin V. V. , Kosovichev A. G.
Published: November 2018

We explore effects of random nonaxisymmetric perturbations of kinetic helicity (the α effect) and diffusive decay of bipolar magnetic regions on generation and evolution of large-scale nonaxisymmetric magnetic fields on the Sun. Using a reduced 2D nonlinear mean-field dynamo model and assuming that bipolar regions emerge due to magnetic buoyancy in situ of the large-scale dynamo action, we show that fluctuations of the α effect can maintain the nonaxisymmetric magnetic fields through a solar-type α
2Ω dynamo process. It is found that diffusive decay of bipolar active regions is likely to be the primary source of nonaxisymmetric magnetic fields observed on the Sun. Our results show that nonaxisymmetric dynamo models with stochastic perturbations of the α effect can explain periods of extremely high activity (“super-cycle” events) as well as periods of deep decline of magnetic activity. We compare the models with synoptic observations of solar magnetic fields for the last four activity cycles and discuss implications of our results for interpretation of observations of stellar magnetic activity.
Systèmes d’emprise dans les mondes du travail
Authors: Jamoulle Pascale
Published: November 2018

Nous explorerons la problématique de l’emprise socio-professionnelle à partir d’une étude de cas princeps, celle d’un chauffeur-livreur dans une entreprise de transport. Avec lui, nous chercherons à démonter les rouages des systèmes d’emprise au travail et les atteintes subjectives et sociales vécues. Dans une approche d’ethnographie clinique, nous explorerons en aval, les modes opératoires de la violence et de l’emprise au travail et, en amont, les vulnérabilités qui ont souvent affaibli les protections des personnes. Dans une situation d’emprise, des composants viennent souvent se cristalliser d’une dimension de l’existence à l’autre, de la vie privée à la vie socio-professionnelle. Enfin, en final, nous explorerons les processus de déprise et de (re)construction d’un rapport soutenable au travail.
Nier la souffrance au travail, naturaliser la violence sociale : un écueil psycho-thérapeutique centenaire
Authors: Demaegdt Christophe
Published: November 2018

Cet article aborde certaines difficultés conceptuelles auxquelles les cliniciens qui font face à la souffrance au travail de leurs patients peuvent se confronter, dès lors qu’ils se réfèrent à la théorie psychanalytique. En partant de l’analyse des textes relatifs à l’entité fondatrice de la psychopathologie psychanalytique du travail, à savoir les névroses de guerre, l’article montre que la conceptualisation freudienne passée à la postérité, et considérée aujourd’hui comme classique, procède d’un déni de la souffrance et travail, assortit d’une naturalisation de la violence sociale. Force est alors de constater que cette psychanalyse ne dispose pas des outils conceptuels qui permettent de se référer au travail, de l’écouter, de le comprendre, et de l’interpréter. L’auteur propose de reprendre certaines propositions conceptuelles de Freud, originales mais restées sans suite, et de les réexaminer à partir de la référence à la clinique du travail contemporaine. En conclusion, il s’agira d’envisager une théorie sociale psychanalytique alternative au modèle canonique, qui accorderait une place centrale à la référence au travail.
La prise de risque et l’exposition au danger des travailleurs sociaux dans leur activité
Authors: Benhaïm Michèle
Published: November 2018

Ce texte pose la question fondamentale de la souffrance au travail des pompiers contemporains que sont aujourd’hui les travailleurs sociaux. La construction de l’identité de travailleur social a toujours reposé sur des notions aux accents de valeurs telles que l’engagement, l’implication, la détermination. Qu’en est-il aujourd’hui alors que les travailleurs sociaux sont confrontés à des données inédites, à la transformation du travail social qui s’est opérée ces dernières décennies, à la diversification des publics, à la régression, voire à la destruction des conditions de l’action, à la complexification des rapports du social avec les financeurs et les politiques ?
A Data Driven Educational Decision Support System
Authors: Zhu Yaqiong
Published: November 2018

To make use of the latest Internet technology to provide innovative support for teacher education, a comprehensive study is made on DDEDSS (data driven education decision support system) and DDEDSS software prototype is designed and developed as an auxiliary tool for educational decision-making. At the same time, the two sessions of education data is collected and tested in practice. The multidimensional summation and average are carried out for different time, different source regions, different gender learners and different subjects. The research results show that the system can evaluate learners' learning and further provide decision-making basis for curriculum optimization and class adjustment. It can be seen that DDEDSS is a frontier educational research, which has important research significance.
An Algorithm for Generating a Recommended Rule Set Based on Learner's Browse Interest
Authors: Hao Xiaowei , Han Shanshan
Published: November 2018

To personalize the recommended learning information according to the interests of the learner, a recommendation rule set generation algorithm based on learner browsing interests was proposed. First, the learner's browsing behavior was captured. A multivariate regression method was used to calculate the quantitative relationship between the learner's browsing behavior and the degree of interest in the web page to generate a learner's current interest view (CIV). With this current interest view, a content-based collaborative filtering personalized information recommendation service was provided to learners. Then, a new weighted association rule algorithm was used to discover the associations between the items, so that the degree of recommendation was obtained. Furthermore, the degree of recommendation was used as a personalized recommendation service for learners with long-term interests. The results showed that the proposed algorithm effectively improved the quality of information recommendation and the real-time performance of the recommendation. Therefore, this algorithm has a good application value in the field of personalized learning recommendation.
Emotional Tendency Dictionary Construction for College Teaching Evaluation
Authors: Shen Weiwen , Zhang Shuping
Published: November 2018

To deal with a large amount of emotional information, the text was analyzed by constructing a sentiment dictionary. The mining system was used in the teaching evaluation of colleges and universities. Taking the high-quality emotional dictionary construction algorithm as the research object, a general emotion dictionary construction method based on function optimization was proposed. This method transformed the universal emotion dictionary construction problem into a function optimization problem and used a simulated annealing algorithm to solve it. A universal sentiment dictionary was constructed using the Modularity optimization method in the discovery of complex web communities. In addition, the traditional Modularity method was improved. The results showed that the improved method only compared the Modularity values for all bipartite cases and optimized them. This not only made Modularity method applicable to this problem, but also greatly reduced the amount of computation. In summary, the traditional information clustering method is improved. By making full use of the relationship between the emotional words and documents in the source domain and the target domain, the domain emotional dictionary in the target domain is established.
Solar Energy Absorbing Materials that are Capable of Withstanding Long-Term Exposure at 600 °C: Research Strategy
Authors: Pavlovska Ilona , Mežinskis Gundars , Bīdermanis Laimons Paulis
Published: November 2018

Pipes for parabolic-trough solar energy collectors (PTSC) must be able to operate and withstand high temperatures in corrosive environments for a long time without changing its microstructure and losing its original properties. The stages of development of a new material and technology for solar energy collectors that allows the production of a PTSC solar energy-absorbing material that is capable of withstanding temperatures ≥ 600 °C for at least 250 days are described. This material is a glass-crystalline enamel coating that is adhered to tubular stainless steel pipes. Such enamel coatings have high coefficients of thermal expansion (CTE) that are similar to the metal surface. These matching CTEs allow the enamel coatings to resist flaking during the heating at 900 °C. The high-temperature resistance of the developed coating was ensured not only by specific additives added to the frit of the coating but also by an additional nanosized sol-gel coating over the enamelled metal substrate.
Increase of Temperature and Fire Resistance for Reinforced-Concrete Structures by Surface Treatment with Protective Coating
Authors: Demydchuk Liudmyla , Sapozhnyk Dmytro
Published: November 2018

The normative documents of Ukraine (DBN V.1.1.7 ̶ 2016) [1] establish that the limit of fire resistance of reinforced-concrete building structures is determined by the calculation method or by fire tests, and shall be at least 45 minutes. Taking into account the modern construction technologies, namely, the reduction of the section of the main building reinforced-concrete structures, it is expedient to use fire-retardant coatings to provide the necessary fire resistance limit.
Natural Radioactivity in Clay Ceramics and their Raw Materials in Latvia
Authors: Riekstina Daina , Krasta Tamara , Švinka Ruta
Published: November 2018

Natural radionuclides K-40, and Th-232, U-238 (Ra-226) decay chain products contained in building materials are the main source of radiation dose received by population and the only source of indoor radiation exposure. Present work contains results of the study of natural radionuclide activity level in clay, clay ceramics and silica bricks used in Latvia. Obtained data show that radionuclide content in different clay products can differ up to five times. However, determined activity index values for all tested materials, except fireproof bricks, were below radionuclide concentration level permitted by EU and Latvian national regulations. Comparison with analogous data from other North European and Baltic countries shows that average concentrations of natural radionuclides and activity index values for clay and clay bricks used in Latvia are on the same level as in other countries, except Sweden.
Adsorption of Organic Compounds on Refined Latvian Clay
Authors: Leščinskis Oskars , Švinka Ruta , Švinka Visvaldis
Published: November 2018

Clays are materials consisting of clay minerals and non-clay minerals. Clay mineral fraction is considered to be a nanofraction. Clay minerals can be used for water purification and treatment. Description and characterization of 3 different Latvian clay nanosized minerals from 3 different geological periods (clay Liepa from Devonian period, clay Vadakste from Triassic period and clay Apriki from Quaternary period) as well as their adsorption capacity concerning organic compounds such as methyl orange and rhodamine B are summarized. Nanosized clay mineral particles were obtained using sedimentation method. Particle size distribution, zeta potential and FTIR spectra is given. The adsorption tests of above mentioned organic compounds were carried out in water solutions at 3 different pH values. The adsorption values were determined by means of UV-spectrophotometric technique. Zeta potential values for clay minerals Apriki, Liepa and Vadakste are -40.9 mV, -49.6 mV and -43.0 mV, respectively. FTIR spectra show similar tendencies for all 3 clay minerals. The best adsorption capacity concerning methyl orange and rhodamine B were in solutions with a pH value of 2, whereas at neutral and alkaline pH values adsorption in 24 hours was not observed.
Late-acting self-incompatibility and a narrow floral tube as selective forces for stylar dimorphism in Narcissus (Amaryllidaceae): A response to Simón-Porcar
Authors: Faivre Amy
Published: November 2018

Simón-Porcar proposes an alternative origin in the evolutionary pathway to heterostyly as described in a model proposed by Lloyd and Webb. Below I summarize her key points and namely consider the implications of comparing her model to ideas within the Charlesworth and Charlesworth model. The hypothesis that she has chosen to propose is similar to ones that others have proposed for this same genus, thus I have tried to distinguish how Simón-Porcar’s hypothesis differs from theirs, as well as give credit to their contributions to these ideas. Finally, I have added a few more suggestions related to testing her hypothesis.
Silver nanoparticles impregnated with polyamide-66 to disinfect drinking water
Authors: Koslowski Luciano André Deitos , Nogueira André Lourenço , Licodiedoff Silvana , Comper Adrieny Taliny , Folgueras Marilena Valadares
Published: November 2018

The importance of the preservation of water resources has resulted in the application of technologies such as nanostructured materials, which are able to minimize the impact associated with water contamination. This work evaluated the application of polyamide-66 (PA) pellets functionalized with silver nanoparticles (AgNPs) at polymer mass percentages of 0.05, 0.10 and 0.50% to disinfect of drinking water. Studies were carried out in three stages. The first stage was the synthesis of the silver nanoparticles by using silver nitrate as a metal precursor and sodium borohydrate as a reduction agent. The colloidal dispersion was characterized by UV-Vis spectrophotometry and transmission electron microscopy (MET). Afterwards, the nanostructures were incorporated into a polyamide-66 polymeric matrix. In the second stage, the silver ions leached from the polymer matrix in the water after a three-hour period were quantified in order to evaluate the limit established by Conama Resolution 357/2005, which imposes a concentration limit of 0.010 mg L-1. The best results were obtained with the application of 0.05% AgNPs in the polymeric matrix, yielding an average concentration of silver ions lixiviated of 0.008 mg L-1. The last step comprised the quantification of the antibacterial activity of the polymer matrix containing 0.05% of AgNPs against the microorganism E. coli using the Standard Test Method for Determining the Antimicrobial Agents Under Dynamic Contact Conditions. The samples containing 0.05% of AgNPs exhibited an antibacterial reduction of 97.89% after 24 h of incubation under stirring at room temperature (25°C).
Sensitivity analysis of the Soil and Water Assessment Tools (SWAT) model in streamflow modeling in a rural river basin
Authors: Moreira Luana Lavagnoli , Schwamback Dimaghi , Rigo Daniel
Published: November 2018

The uncertainties present in hydrological models have made them difficult and often impossible to apply. This work evaluated the sensitivity of input parameters in the SWAT model used for the modeling of average monthly flow-discharge in the Jucu River Basin, located in the southeast portion of the state of Espírito Santo, Brazil. Sensitivity analysis was performed using the SWAT-CUP program, which uses the SUFI-2 algorithm. Four sensitivity analysis tests differing by the length of hydrological series, number of iteration and fluviometric station locations resulted in different sensitivity levels of input parameters used in the model. In this way, the present study emphasizes the need for a greater detailing of methodological processes used in the sensitivity analysis, so that different hierarchies of parameters can be obtained through the same tool.
Low-Temperature Coolant Circuit Nomenclature and Applications
Authors:   Cooling Systems Standards Committee
Published: November 2018

The document provides clarity related to multiple temperature coolant circuits used in on- and off-highway, gasoline, and light- to heavy-duty diesel engine cooling systems.

Out of scope are the terms and definitions of thermal flow control valves used in either low- or high-temperature coolant circuits. This subject is covered in SAE J3142.
Hybridizing Bayesian and variational data assimilation for high-resolution hydrologic forecasting
Authors: Hernández Felipe , Liang Xu
Published: November 2018

Abstract. The success of real-time estimation and forecasting applications based on
geophysical models has been possible thanks to the two main existing
frameworks for the determination of the models' initial conditions: Bayesian
data assimilation and variational data assimilation. However, while there
have been efforts to unify these two paradigms, existing attempts struggle to
fully leverage the advantages of both in order to face the challenges posed
by modern high-resolution models – mainly related to model indeterminacy and
steep computational requirements. In this article we introduce a hybrid
algorithm called OPTIMISTS (Optimized PareTo Inverse Modeling through
Integrated STochastic Search) which is targeted at non-linear high-resolution
problems and that brings together ideas from particle filters (PFs),
four-dimensional variational methods (4D-Var), evolutionary Pareto
optimization, and kernel density estimation in a unique way. Streamflow
forecasting experiments were conducted to test which specific configurations
of OPTIMISTS led to higher predictive accuracy. The experiments were
conducted on two watersheds: the Blue River (low resolution) using the VIC
(Variable Infiltration Capacity) model and the Indiantown Run (high
resolution) using the DHSVM (Distributed Hydrology Soil Vegetation Model). By
selecting kernel-based non-parametric sampling, non-sequential evaluation of
candidate particles, and through the multi-objective minimization of
departures from the streamflow observations and from the background states,
OPTIMISTS was shown to efficiently produce probabilistic forecasts with
comparable accuracy to that obtained from using a particle filter. Moreover,
the experiments demonstrated that OPTIMISTS scales well in high-resolution
cases without imposing a significant computational overhead. With the
combined advantages of allowing for fast, non-Gaussian, non-linear,
high-resolution prediction, the algorithm shows the potential to increase the
efficiency of operational prediction systems.
Usability of a classroom response system in an online course: Testing of a smartphone-downloadable technology enhanced learning tool for distance education
Authors: Pajarillo Edmund J.Y. , Kaplan Daniel B.
Published: November 2018

Background and objective: Classroom response systems (CRS) have been used in higher education since the 1990s to enhance student learning and engagement. It began with portable “TV remote control-looking” devices that students used in class to answer questions posed by the professor. Aggregated responses are available instantaneously and projected on the screen to serve as a feedback mechanism for the professor and students to gauge learning, potentially prompt further review of the topics, or inspire further discussion. Companies which produce CRS tools are beginning to develop apps to allow students to use their own technology mobile devices during similar learning activities. Many educational institutions are increasingly offering distance education courses and programs, yet little is currently known about the effectiveness of CRS integration into online courses. This usability study was conducted to determine whether a technology enhanced learning tool, specifically a CRS that can be downloaded to one’s smartphone, would be suitable for adoption in online classes in one particular suburban university in New York.Methods: The study is a mixed method, one group, pretest/posttest descriptive design. Convenience sampling (n = 48) was used to engage students enrolled in an online nursing course during their first semester in a master’s degree program. A five-point Likert scale was designed for respondents to rate 21 statements in terms of their degree of agreement (with 5 being “strongly agree” and 1 being “strongly disagree”). The statements included descriptors of the three usability domains (functionality, support and effectiveness) selected to evaluate the smartphone-based CRS app. Open-ended questions were included to provide contextual perspectives on these criteria.Results: T-tests demonstrated an improvement in student ratings of agreement with the evaluative criteria for this CRS smartphone app when comparing pre- and post-implementation survey data. This includes agreement with the CRS’s functionality (p = .001), support (p = .004) and effectiveness (p = .189) at α = 0.05, as well as overall usability across criteria domains (p = .000 at α = 0.05). Respondents additionally suggested that specific features be changed or added to the current design to make it easier to navigate.Conclusions: For educational apps to achieve optimal use and effectiveness, iterative design assessments should continue until the end-users truly benefit from the technology enhanced learning tool. This smartphone-downloadable CRS app proved to be a useful adjunctive tool for enhancing student learning in an online class. Yet there were numerous design recommendations provided by students that could further improve its usability.
Importance of Dealing with Cybersecurity Challenges and Cybercrime in the Senior Population
Authors: Lošonczi Peter
Published: November 2018

This article deals with the importance of focusing seniors’ attention on cybercrime and cybersecurity.
We should perceive cybersecurity as a key component of state security. Technological
development has brought new forms of crime in this area. The people above 55
belong to the most vulnerable group in terms of cybersecurity threats and consequently
they become a common target for cyber criminals. Prevention in this area is therefore
of the utmost importance. Information and communication technologies make our lives
easier. They speed up communication and information access and as well as access to various
services on one hand. But in case of insufficient security, an increasing dependency
of the public and private sector on these technologies is increasing the threat of a cybercrime.
This makes cybersecurity one of the biggest challenges that need to be properly
addressed by the state.
Por que existe o dia e a noite? Uma proposta de ensino interdisciplinar em museu interativo
Authors: De Vargas Matos Diego , Purper Thiele Ana Lúcia , Machado de Lara Isabel Cristina , Ferraro José Luis
Published: November 2018

Este artigo apresenta o relato de experiência advindo da realização de um projeto de ensino interdisciplinar acerca do tema Rotação da Terra com estudantes de quinto ano do Ensino Fundamental de uma escola pública de Porto Alegre, RS. Objetiva verificar as mudanças na percepção dos estudantes acerca do motivo da existência do dia e da noite na Terra ocasionada pela exploração de recursos disponibilizados por um museu interativo. Para tanto, foi realizada uma pesquisa qualitativa, analisando e comparando as respostas dadas pelos estudantes a um pré e pós questionário por meio da Análise Textual Discursiva. Utilizou-se a Modelagem Matemática como método de ensino e um museu interativo como espaço não formal de educação durante a realização do projeto. Evidencia que a exploração de museus interativos aliada à utilização da Modelagem Matemática como método de ensino causou uma mudança significativa na percepção que os estudantes tinham sobre a existência do dia e da noite na Terra. Além disso, aponta a eficácia de projetos interdisciplinares de ensino para aprimorar a visualização e a compreensão dos estudantes a respeito do mundo em que vivem.