bluuebunny/crossref_metadata_2025 huggingface dataset:
Inverse Simulation for Extracting the Flow Characteristics of Artificial Snow Avalanches Based on Computation Fluid Dynamics
Authors: Oda Kenichi , Nakamura Katsuya , Kobayashi Yoshikazu , Suzumura Jun-ichi
Published: June 2020

Many numerical analysis methods for predicting the motion of soil or snow avalanches may set the characteristics of the dynamic friction obtained from field tests, such as the measurement of real avalanche and model slope tests. However, the friction characteristics of the actual flow of objects are influenced by changes in the velocity and density of the flowing objects and are not necessarily constant. In addition, determining the shear strain rate dependence of the frictional properties at low shear strain rates is important for accurately predicting the avalanche reach distance. In this research, model tests using a rotating drum device were carried out, and an artificial snow avalanche was generated. Then, the flow velocity distribution of the flow was extracted by organizing the motion of the artificial snow avalanche flowing in the drum device using the Digital Image Correlation method. Moreover, the changing characteristics of the viscosity coefficient of the pseudo flow were estimated using an inverse simulation. For the results, it was suggested that the method of estimating flow characteristics and friction characteristics from the artificial avalanche generated by the rotating drum and the time inverse analysis proposed in this study was effective, but it is necessary to confirm the issue of the need for a similar analysis using real scale. If it is found to be applicable to real scales in the future, it will contribute to the development of this field because it will expand the range of methods for analyzing avalanches using model experiments.
Assessment of Geotechnical Seismic Isolation (GSI) as a Mitigation Technique for Seismic Hazard Events
Authors: Forcellini Davide
Published: June 2020

Geotechnical seismic isolation (GSI) has emerged as a potential technique to mitigate the effects of earthquakes, with many applications to structural configurations, such as bridges and buildings. It consists of absorbing the seismic energy from the soil to the superstructure by interposing a superficial soil layer in order to reduce the accelerations that filter from the soil to the structure. This mitigation technique is particularly suitable in developing countries since GSIs are low-cost seismic isolation systems that through relatively simple manufacturing processes allow to safe costs and stimulate many applications. The presented study aimed to perform 3D numerical finite element models that overcome the previous contributions by performing several structural configurations. Several historical earthquakes are considered in this paper, and the results may be applied to drive general assessments of the technique in case of future seismic hazards.
Cognitive and Social Rehabilitation in Schizophrenia—From Neurophysiology to Neuromodulation. Pilot Study
Authors: Markiewicz Renata , Dobrowolska Beata
Published: June 2020

The aim of this pilot study was to analyse the influence of Galvanic Skin Response (GSR) Biofeedback training in a group of 18 men with schizophrenia at the remission stage. The results were verified according to: Positive and Negative Syndrome Scale (PANSS), Acceptance of Illness Scale (AIS), Self-efficacy Scale (GSES), Beck Cognitive Insight Scale (BCIS) scales, Colour Trial Test (CTT-1, CTT-2), d2 psychological tests, Quantitative Electroencephalogram (QEEG) Biofeedback, auditory event-related potentials (ERPs), and serum levels of brain-derived neurotrophic factor (BDNF). The results were compared in the same patients after 3 months. Statistically significant changes were noted in results for the variables on the PANSS scale. For the BDNF variable, a statistically significant increase occurred, indicating that GSR Biofeedback training may influence serum levels of the neurotrophic factor. Statistically significant changes were noted in results for the variables on the BCIS, AIS, and GSES indicating an improvement in the cognitive and social functioning. Changes were noted for results for theta/beta and theta/Sensory Motor Rhythm (SMR) ratios, which indicate an improvement in concentration and attention. Changes were noted for the N1 wave amplitude in the frontal brain region (F-z), and for the P2 wave latency in the central brain region (C-z), which indicates an improvement in the initial perceptual analysis. The use of GSR Biofeedback in a group of patients with schizophrenia gives interesting results, but requires further in-depth research.
Manipulating Self-Avatar Body Dimensions in Virtual Worlds to Complement an Internet-Delivered Intervention to Increase Physical Activity in Overweight Women
Authors: Navarro Jessica , Cebolla Ausiàs , Llorens Roberto , Borrego Adrián , Baños Rosa M.
Published: June 2020

Virtual reality has been found to be a useful tool for positively influencing relevant psychological variables in order to increase physical activity (PA), especially in the overweight population. This study investigates the use of avatars and their physical variations to extend the effectiveness of existing interventions to promote PA. The main objective is to analyze the influence of the avatars’ body dimensions on the efficacy of an Internet intervention to increase PA levels and improve other relevant variables (motivation toward PA, enjoyment, anxiety, self-efficacy, and PA goals). A total of 42 overweight women received a brief online intervention, and they were randomly assigned to one of three conditions: the “Ideal avatar” (IAC: participants are represented by avatars with ideal body dimensions); the “Real avatar” (RAC: participants are represented by avatars with participants’ current body dimensions); and the “Non avatar” (NAC: participants are not represented by avatars). Results showed that the online intervention was effective in increasing PA practice and self-efficacy expectations. However, manipulating the body dimensions of avatars did not improve this intervention, although ideal avatars helped to reduce the anxiety experienced during PA in this population.
Teacher Harassment Victimization in Adolescents with High-Functioning Autism Spectrum Disorder: Related Factors and Its Relationships with Emotional Problems
Authors: Lin Po-Chun , Peng Li-Yun , Hsiao Ray C. , Chou Wen-Jiun , Yen Cheng-Fang
Published: June 2020

This study aimed to examine the prevalence, related factors, and emotional problems associated with teacher harassment victimization in adolescents with autism spectrum disorder (ASD) assessed by self-reports and parent reports. A total of 219 adolescents with ASD participated in this study. The self-reported and parent-reported rates of teacher harassment victimization were calculated. Sociodemographic characteristics, parent-reported social communication deficits, attention-deficit and hyperactivity disorder (ADHD) symptoms, oppositional defiant disorder (ODD) symptoms, self-reported depression and anxiety symptoms, and suicidality were surveyed. In total, 26 (11.9%) adolescents with ASD experienced teacher harassment based on self-reports or parent reports; the convergence between adolescent and parent reports on adolescent experiences of teacher harassment was low. Victims of teacher harassment exhibited more severe social communication deficits and ODD symptoms than nonvictims of teacher harassment. Victims of teacher harassment displayed more severe depression and anxiety and were more likely to have suicidality. Socio-communication deficits and ODD symptoms were related to teacher harassment victimization, which in turn was significantly associated with emotional problems among adolescents with ASD.
Correlation between Preventive Health Behaviors and Psycho-Social Health Based on the Leisure Activities of South Koreans in the COVID-19 Crisis
Authors: Kim Young-Jae , Cho Jeong-Hyung
Published: June 2020

COVID-19 has caused unprecedented damage worldwide, and quarantine and lockdown measures have been undertaken globally. This study focused on the differences in preventive behaviors and psycho-social health of South Koreans, as people continue engaging in leisure activities under self-regulation without a lockdown measure imposed by the government. For the sample, the frame of the “2018 Population and Housing Census” in South Korea was applied, and data from 1770 people were analyzed. The results showed that the groups participating in culture and arts and social activities displayed characteristics with high prevention. Additionally, the groups that continued leisure activities for more than five years and with family showed high preventive behaviors. Meanwhile, participation in leisure activities with friends of the opposite sex lowered preventive behavior. In terms of psycho-social health, all groups were affiliated to the potential stress group and there were no differences in the period and participation time for leisure activities. Furthermore, the group participating in leisure activities with their school and group experienced psychological stability. When lockdown measures are eased, the aforementioned characteristics should be considered to design government policy; they can also be used as a reference for public health in case of a future outbreak of an epidemic.
Relationships of Dental Caries and Malocclusion with Oral Health-Related Quality of Life in Lithuanian Adolescents Aged 15 to 18 Years: A Cross-Sectional Study
Authors: Kavaliauskienė Aistė , Šidlauskas Antanas , Žemaitienė Miglė , Slabšinskienė Eglė , Zaborskis Apolinaras
Published: June 2020

There is a lack of evidence of the moderating effects of caries lesions and malocclusions on oral health-related quality of life (OHRQoL) among older adolescents. This study aimed to evaluate the relationship of dental caries and malocclusion with OHRQoL among Lithuanian adolescents aged 15 to 18 years. A survey in a representative sample of adolescents included a clinical examination to assess dental health status using the DMFT (Decayed, Missing, and Filled Permanent Teeth) index, and malocclusion using the Index of Complexity, Outcome, and Need (ICON). The Child Perceptions Questionnaire (CPQ) was used to evaluate respondents’ OHRQoL. Negative binomial regression was fitted to associate the clinical variables with the CPQ scores. A total of 600 adolescents were examined. The overall mean DMFT score was 2.7. A need for orthodontic treatment was detected among 27.7% of adolescents. Subjects with caries lesions (DMFT > 3) had higher CPQ scores in the domains of functional limitations and social wellbeing (relative risks were 1.35 (95% confidence interval: 1.09–1.67) and 1.30 (1.03–1.64), respectively), while subjects with a need for orthodontic treatment (ICON > 43) had higher CPQ scores in the domains of emotional wellbeing and social wellbeing (relative risks were 1.81 (1.40–2.22), and 1.69 (1.34–2.14), respectively). It was concluded that both dental caries and malocclusion have negative relationships with OHRQoL in adolescents above 15 years, but their effects occur differently in each OHRQoL domain.
Regional Spatial Management Based on Supply–Demand Risk of Ecosystem Services—A Case Study of the Fenghe River Watershed
Authors: Zhang Hongjuan , Feng Juan , Zhang Zhicheng , Liu Kang , Gao Xin , Wang Zidong
Published: June 2020

The supply–demand risk assessment of ecosystem services (ES) can identify the supply–demand risk level, which is very important for the sustainable management of regional ES. In this study, taking the Fenghe River watershed (FRW) as a case, based on the status and the change trend of the supply–demand ratio of ES, and the ES supply change trend, the supply–demand risk level of food provision (FP), water yield (WY), soil retention (SR), and climate regulation (CR) are evaluated, and the risk management zones of the FRW are divided using spatial superposition. The results show that: (1) The supply and demand of SR are spatially matched, while the other three ES are spatially mismatched. (2) From 2000 to 2015, the supply amount of FP, WY, and SR increases by 11.59%, 1.25% and 55%, respectively, while the supply amount of CR decreases by 5.15%. At the same time, the demand amount of FP, WY, SR and CR increases by 39.97%, 53.88%, 36.3% and 215.5%, respectively. (3) The supply–demand ratio means of four ES in the FRW are all greater than 0, but there are some areas within that are less than 0. (4) In terms of sub-watershed scale, except for SR, there are critically endangered areas for the other three ES. Moreover, the FRW is divided into 11 supply–demand risk management zones, such as FS-WY-CR critically endangered zone, WY-CR critically endangered and FS vulnerable zone. The supply–demand risk management zones based on multiple ES can identify the risk level of each ES in each zone. These results and conclusions can provide the basis for rational allocation of resources and sustainable management of ES.
Application Programming Interface for the Cloud-Based Management of Gamified eGuides
Authors: Kulpa Artur , Swacha Jakub
Published: June 2020

The popularity of smartphones and widespread access to mobile internet removed earlier barriers to reliance on mobile applications run on visitors’ own devices for guidance in tourist attractions. At the same time, the tourists’ rising expectations call for solutions that can increase their engagement and satisfaction, such as gamification. Despite the availability of platforms for both general-purpose gamification and configurable eguides, until now, there have not been any ready-made solutions of this kind supporting the implementation of gamification for eguides. In this paper, we would like to present a solution filling this gap: the eMused.eu Application Programming Interface, which can be used by mobile applications (web or native) to access both tour content and gamification functionality provided on a cloud.
Conveyor-Belt Dryers with Tangential Flow for Food Drying: Mathematical Modeling and Design Guidelines for Final Moisture Content Higher Than the Critical Value
Authors: Friso Dario
Published: June 2020

The mathematical modeling presented in this work concerns the conveyor-belt dryer with the tangential flow of air with respect to food. This dryer, if operating in co-current, has the advantage of well preserving the organoleptic and nutritional qualities of the dried product. In fact, it has a low air temperature in the final stretch where the product has low moisture content and is therefore more temperature sensitive. It is a bulkier dryer than the continuous through-circulation conveyor dryer with a perforated belt. The latter is therefore more frequently used and has received greater study attention from researchers and designers of the industry. With the aim to propose guidelines for a rational design of the conveyor-belt dryer with tangential flow, a mathematical model was developed here through the differentiation of the drying rate equation followed by its integration performed along the dryer belt. Consequently, and with the assumption that the final moisture content XF of the product is higher than the critical moisture content XC, the relationships between the intensive quantities (temperatures, humidity and enthalpies), the extensive quantities (air and product flow rates) and the dimensional ones (length and width of the belt), were obtained. Finally, on the basis of these relationships, the rules for an optimized design for XF > XC were obtained and experimentally evaluated.
Dermatofibrosarcoma Protuberans: Update on the Diagnosis and Treatment
Authors: Hao Xingpei , Billings Steven D. , Wu Fangbai , Stultz Todd W. , Procop Gary W. , Mirkin Gene , Vidimos Allison T.
Published: June 2020

Dermatofibrosarcoma protuberans (DFSP) is a slow growing, low- to intermediate-grade dermal soft-tissue tumor. It has a high local recurrence rate but low metastatic potential. It is characterized by a uniform spindle cell arrangement, classically with a storiform pattern and CD34 immunoreactivity. The histomorphology and immunophenotype overlap with a broad range of other neoplasms. The standard treatment is complete surgical excision. The surgical procedures include wide local excision (WLE) with tumor free margins, Mohs micrographic surgery (MMS) and amputation. Unresectable DFSPs are treated with radiation therapy and/or targeted therapy. DFSP has characteristic t(17; 22) (q22; q13), resulting in a COL1A1- PDGFB fusion transcripts in more than 90% of DFSPs. Molecular detection of the gene rearrangement or fusion transcripts is helpful for the diagnosis of patients with atypical morphology and for screening candidates for targeted therapy with tyrosine kinase inhibitors. The aims of the present review are to update the clinical presentation, tumorigenesis and histopathology of DFSP and its variants for diagnosis and differential diagnosis from other benign and malignant tumors, to compare the advantages and drawbacks of WLE and MMS, to propose the baseline for selecting surgical procedure based on tumor’s location, size, stage and relationship with surrounding soft tissue and bone structures, and to provide a biologic rationale for the systemic therapy. We further propose a modified clinical staging system of DFSP and a surveillance program for the patients after surgical excision.
Body Fat Assessment in International Elite Soccer Referees
Authors: Petri Cristian , Campa Francesco , Hugo Teixeira Vitor , Izzicupo Pascal , Galanti Giorgio , Pizzi Angelo , Badicu Georgian , Mascherini Gabriele
Published: June 2020

Soccer referees are a specific group in the sports population that are receiving increasing attention from sports scientists. A lower fat mass percentage (FM%) is a useful parameter to monitor fitness status and aerobic performance, while being able to evaluate it with a simple and quick field-based method can allow a regular assessment. The aim of this study was to provide a specific profile for referees based on morphological and body composition features while comparing the accuracy of different skinfold-based equations in estimating FM% in a cohort of soccer referees. Forty-three elite international soccer referees (age 38.8 ± 3.6 years), who participated in the 2018 Russian World Cup, underwent body composition assessments with skinfold thickness and dual-energy X-ray absorptiometry (DXA). Six equations used to derive FM% from skinfold thickness were compared with DXA measurements. The percentage of body fat estimated using DXA was 18.2 ± 4.1%, whereas skinfold-based FM% assessed from the six formulas ranged between 11.0% ± 1.7% to 15.6% ± 2.4%. Among the six equations considered, the Faulkner’s formula showed the highest correlation with FM% estimated by DXA (r = 0.77; R2 = 0.59 p < 0.001). Additionally, a new skinfold-based equation was developed: FM% = 8.386 + (0.478 × iliac crest skinfold) + (0.395 × abdominal skinfold, r = 0.78; R2 = 0.61; standard error of the estimate (SEE) = 2.62 %; p < 0.001). Due to these findings, national and international federations will now be able to perform regular body composition assessments using skinfold measurements.
Review of Shearing Processes of High Strength Steel Sheets
Authors: Mori Ken-ichiro
Published: June 2020

Shearing processes of high strength steel sheets increasingly applied to lightweight automobile parts were reviewed. With the increase in strength of the high strength steel sheets, shearing operations become hard. First, the sheared edge quality in shearing of high strength steel sheets and the effects on the formability and fatigue strength were shown. Next, ironing processes with a taper punch and a punched slug, a slight clearance punching with a punch having a small round corner and a thickening process of the sheared edge were explained as processes for improving the sheared edge quality. Finally, hydrogen-induced delayed fractures of cold-sheared ultra-high strength steel sheets and of hot-trimmed parts were evaluated.
Legislation, Regulations, and Reflections on Environmental Accounting as a Reflection of the Incorporation of Social Responsibility in Companies
Authors: Muñoz Prieto Maripaz
Published: June 2020

The purpose of this article is to analyze how accounting legislation has contributed to the improvement of public information on environmental aspects in the financial reports issued by companies. Also, the article aims to verify the relationship between this environmental accounting legislation and the processes of corporate social responsibility. These reports are used for decision making, so any improvement in the publication should mean a better business strategy. Companies should seek to improve their relationship with the environment, helping to minimize the environmental problems caused by their production systems. The methodology used in this study has been the deductive method, through the bibliographic review, and a descriptive research level was used. Among the main results of this work are a summary table with regulations related to environmental care, evidence of the lack of specific legislation, and the need for more demanding regulations with companies when providing environmental data.
Synthesis, Structure and Hirshfeld Surface Analysis of Phosphine–Imidazolium Salt
Authors: Smarun Alexey , Jevtovic Violeta , Ganguly Rakesh
Published: June 2020

In the field of homogeneous catalysis, particularly in anti-Markovnikov hydration, sterically demanding phosphine ligand has found to be very effective. Here we report the crystal structure of a phosphine-imidazolium salt which crystallized in monoclinic space group P21/c with a = 16.6623(13) (Å), b = 10.6686(8) (Å) and c = 12.8916(11) with = 110.232(2). Hirshfeld surface analysis show that the halogen–hydrogen interaction leads to a formation of 1D chain.
Flexural Damage of Honeycomb Paperboard—A Numerical and Experimental Study
Authors: Czechowski Leszek , Śmiechowicz Wojciech , Kmita-Fudalej Gabriela , Szewczyk Włodzimierz
Published: June 2020

This paper presents an experimental and numerical analysis using the finite element method (FEM) of the bending of honeycomb-core panel. Segments of honeycomb paperboard of several thicknesses were subjected to four-point flexure tests to determine their bending stiffness and maximum load. Several mechanical properties of orthotropic materials were taken into account to account for the experimental results. The numerical analysis of the damage prediction was conducted by using well-known failure criteria such as maximum stress, maximum strain and Tsai-Wu. The present study revealed how to model the honeycomb panel to obtain curves close to experimental ones. This approach can be useful for modelling more complex structures made of honeycomb paperboard. Moreover, thanks to the use of variously shaped cells in numerical models, i.e., the shape of a regular hexagon and models with a real shape of the core cell, results of the calculation were comparable with the results of the measurements. It turned out that the increase of maximum loads and rise in stiffness for studied samples were almost either linearly proportional or quadratically proportional as a function of the panel thickness, respectively. On the basis of failure criteria, slightly lower maximum loads were attained in a comparison to empiric maximum loads.
The Generalized H-Bézier Model: Geometric Continuity Conditions and Applications to Curve and Surface Modeling
Authors: Li Fenhong , Hu Gang , Abbas Muhammad , Miura Kenjiro T.
Published: June 2020

The local controlled generalized H-Bézier model is one of the most useful tools for shape designs and geometric representations in computer-aided geometric design (CAGD), which is owed to its good geometric properties, e.g., symmetry and shape adjustable property. In this paper, some geometric continuity conditions for the generalized cubic H-Bézier model are studied for the purpose of constructing shape-controlled complex curves and surfaces in engineering. Firstly, based on the linear independence of generalized H-Bézier basis functions (GHBF), the conditions of first-order and second-order geometric continuity (namely, G1 and G2 continuity) between two adjacent generalized cubic H-Bézier curves are proposed. Furthermore, following analysis of the terminal properties of GHBF, the conditions of G1 geometric continuity between two adjacent generalized H-Bézier surfaces are derived and then simplified by choosing appropriate shape parameters. Finally, two operable procedures of smooth continuity for the generalized H-Bézier model are devised. Modeling examples show that the smooth continuity technology of the generalized H-Bézier model can improve the efficiency of computer design for complex curve and surface models.
The Triads Geometric Consistency Index in AHP-Pairwise Comparison Matrices
Authors: Aguarón Juan , Escobar María Teresa , Moreno-Jiménez José María , Turón Alberto
Published: June 2020

The paper presents the Triads Geometric Consistency Index ( T - G C I ), a measure for evaluating the inconsistency of the pairwise comparison matrices employed in the Analytic Hierarchy Process (AHP). Based on the Saaty’s definition of consistency for AHP, the new measure works directly with triads of the initial judgements, without having to previously calculate the priority vector, and therefore is valid for any prioritisation procedure used in AHP. The T - G C I is an intuitive indicator defined as the average of the log quadratic deviations from the unit of the intensities of all the cycles of length three. Its value coincides with that of the Geometric Consistency Index ( G C I ) and this allows the utilisation of the inconsistency thresholds as well as the properties of the G C I when using the T - G C I . In addition, the decision tools developed for the G C I can be used when working with triads ( T - G C I ), especially the procedure for improving the inconsistency and the consistency stability intervals of the judgements used in group decision making. The paper further includes a study of the computational complexity of both measures ( T - G C I and G C I ) which allows selecting the most appropriate expression, depending on the size of the matrix. Finally, it is proved that the generalisation of the proposed measure to cycles of any length coincides with the T - G C I . It is not therefore necessary to consider cycles of length greater than three, as they are more complex to obtain and the calculation of their associated measure is more difficult.
Improvement of the Fairness of Non-Preemptive Priorities in the Transmission of Heterogeneous Traffic
Authors: Dudin Sergei , Dudina Olga , Samouylov Konstantin , Dudin Alexander
Published: June 2020

A new flexible discipline for providing priority to one of two types of customers in a single-server queue is proposed. This discipline assumes the use of additional finite storages for each type of arriving customer. During the stay in a storage, a customer can leave the system or transfer to the main infinite buffer. Preference to priority customers is provided via the proper choice of the rates of a customer transfer from the storages to the buffer. Analysis of this discipline is implemented under quite general assumptions about the arrival and service processes. The advantage of the proposed discipline over the classical non-preemptive discipline is numerically demonstrated.
Detection of Near-Nulticollinearity through Centered and Noncentered Regression
Authors: Salmerón Gómez Román , García García Catalina , García Pérez José
Published: June 2020

This paper analyzes the diagnostic of near-multicollinearity in a multiple linear regression from auxiliary centered (with intercept) and noncentered (without intercept) regressions. From these auxiliary regressions, the centered and noncentered variance inflation factors (VIFs) are calculated. An expression is also presented that relates both of them. In addition, this paper analyzes why the VIF is not able to detect the relation between the intercept and the rest of the independent variables of an econometric model. At the same time, an analysis is also provided to determine how the auxiliary regression applied to calculate the VIF can be useful to detect this kind of multicollinearity.
Coupled Systems of Nonlinear Integer and Fractional Differential Equations with Multi-Point and Multi-Strip Boundary Conditions
Authors: Di Bin , Chen Guo , Pang Huihui
Published: June 2020

We first consider a second order coupled differential system with nonlinearities involved two unknown functions and their derivatives, subject to a new kinds of multi-point and multi-strip boundary value conditions. Since the coupled system contains two dependent variables and their derivatives, the classical method of upper and lower solutions on longer applies. So we adjust and redefine the forms of upper and lower solutions, to establish the existence results. Secondly, we study a Caputo fractional order coupled differential system with discrete multi-point and integral multi-strip boundary value conditions which are very popular recently, and can accurately describe a lot of practical dynamical phenomena, such as control theory, biological system, electroanalytical chemistry and so on. In this part the existence and uniqueness results are achieved via the Leray-Schauder’s alternative and the Banach’s contraction principle. Finally, an example is presented to illustrate the main results.
On Some Recent Results Concerning F-Suzuki-Contractions in b-Metric Spaces
Authors: Gilić Ersin , Dolićanin-Đekić Diana , Mitrović Zoran D. , Pučić Dženis , Aydi Hassen
Published: June 2020

The purpose of this manuscript is to provide much simpler and shorter proofs of some recent significant results in the context of generalized F-Suzuki-contraction mappings in b-complete b-metric spaces. By using our new approach for the proof that a Picard sequence is b-Cauchy, our results generalize, complement and improve many known results in the existing literature. Further, some new contractive conditions are provided here to illustrate the usability of the obtained theoretical results.
Seaweeds as a Functional Ingredient for a Healthy Diet
Authors: Peñalver Rocío , Lorenzo José M. , Ros Gaspar , Amarowicz Ryszard , Pateiro Mirian , Nieto Gema
Published: June 2020

Seaweeds have been used since ancient times as food, mainly by Asian countries, while in Western countries, their main application has been as gelling agents and colloids for the food, pharmaceuticals, and the cosmetic industry. Seaweeds are a good source of nutrients such as proteins, vitamins, minerals, and dietary fiber. Polyphenols, polysaccharides, and sterols, as well as other bioactive molecules, are mainly responsible for the healthy properties associated with seaweed. Antioxidant, anti-inflammatory, anti-cancer, and anti-diabetic properties are attributed to these compounds. If seaweeds are compared to terrestrial plants, they have a higher proportion of essential fatty acids as eicosapentaenoic (EPA) and docosahexaenoic (DHA) fatty acids. In addition, there are several secondary metabolites that are synthesized by algae such as terpenoids, oxylipins, phlorotannins, volatile hydrocarbons, and products of mixed biogenetic origin. Therefore, algae can be considered as a natural source of great interest, since they contain compounds with numerous biological activities and can be used as a functional ingredient in many technological applications to obtain functional foods.
Electrochemical Characteristics of Glycerolized PEO-Based Polymer Electrolytes
Authors: Mustafa Muhammad S. , Ghareeb Hewa O. , Aziz Shujahadeen B. , Brza M. A. , Al-Zangana Shakhawan , Hadi Jihad M. , Kadir M. F. Z.
Published: June 2020

In this article, poly(ethylene oxide)-based polymer electrolyte films doped with ammonium iodide (NH4I) and plasticized with glycerol were provided by a solution casting method. In the unplasticized system, the maximum ionic conductivity of 3.96 × 10 − 5   S cm−1 was achieved by the electrolyte comprised of 70 wt. % PEO:30 wt. % NH4I. The conductivity was further enhanced up to   ( 1.77 × 10 − 4 S cm−1) for the plasticized system when 10 wt. % glycerol was added to the highest conducting unplasticized one at ambient temperature. The films were characterized by various techniques to evaluate their electrochemical performance. The results of impedance spectroscopy revealed that bulk resistance (Rb) considerably decreased for the highest plasticized polymer electrolyte. The dielectric properties and electric modulus parameters were studied in detail. The LSV analysis verified that the plasticized system can be used in energy storage devices with electrochemical stability up to 1.09 V and the TNM data elucidated that the ions were the main charge carrier. The values of the ion transference number (tion) and electron transfer number (tel) were calculated. The nonappearance of any redox peaks in the cyclic voltammograms indicated that the chemical reaction had not occurred at the electrode/electrolyte interface.
Recovery of Cerium Oxide Abrasive from an Abrasive–Glass Polishing Waste through Alkaline Roasting Followed by Water Leaching
Authors: Wang Li-Pang , Liu Pei-Hsin , Chen Yan-Jhang
Published: June 2020

Abrasive–glass polishing waste is generated from the polishing process of glass components by using cerium oxide abrasive, which contains the cerium oxide abrasive and the polished glass. This study attempted to recover the cerium oxide abrasive from the abrasive–glass polishing waste through removing the polished glass by alkaline roasting using sodium hydroxide (NaOH) followed by water leaching. The experimental results indicated that the polished glass in the abrasive–glass polishing waste could be fully removed under the optimal alkaline roasting and water leaching conditions of roasting temperature of 450 °C, mass ratio of polishing waste to NaOH of 1:1, roasting time of 30 min, leaching pH of 3, leaching temperature of 25 °C, and liquid–solid ratio of 25 mL/g. The characteristics including elemental composition, particle size distribution, mineralogical phases, and morphology of the recovered cerium oxide abrasive obtained under the optimal conditions were similar to those of the original unused one, which was suitable to be reused for polishing again.
Novel Hybrid Conductor of Irregularly Patterned Graphene Mesh and Silver Nanowire Networks
Authors: Sohn Hiesang , Shin Weon , Seok Dohyeong , Lee Taek , Park Chulhwan , Oh Jong-Min , Kim Se , Seubsai Anusorn
Published: June 2020

We prepared the hybrid conductor of the Ag nanowire (NW) network and irregularly patterned graphene (GP) mesh with enhanced optical transmittance (~98.5%) and mechano-electric stability (ΔR/Ro: ~42.4% at 200,000 (200k) cycles) under 6.7% strain. Irregularly patterned GP meshes were prepared with a bottom-side etching method using chemical etchant (HNO3). The GP mesh pattern was judiciously and easily tuned by the regulation of treatment time (0–180 min) and concentration (0–20 M) of chemical etchants. As-formed hybrid conductor of Ag NW and GP mesh exhibit enhanced/controllable electrical-optical properties and mechano-electric stabilities; hybrid conductor exhibits enhanced optical transmittance (TT = 98.5%) and improved conductivity (ΔRs: 22%) compared with that of a conventional hybrid conductor at similar TT. It is also noteworthy that our hybrid conductor shows far superior mechano-electric stability (ΔR/Ro: ~42.4% at 200k cycles; TT: ~98.5%) to that of controls (Ag NW (ΔR/Ro: ~293% at 200k cycles), Ag NW-pristine GP hybrid (ΔR/Ro: ~121% at 200k cycles)) ascribed to our unique hybrid structure.
Phase Transitions in the α–γ–β Spodumene Thermodynamic System and Impact of γ-Spodumene on the Efficiency of Lithium Extraction by Acid Leaching
Authors: Dessemond Colin , Soucy Gervais , Harvey Jean-Philippe , Ouzilleau Philippe
Published: June 2020

Heat-treatment of spodumene concentrate at 1323 K (1050 °C) for 30 min in a rotary kiln yielded a successful decrepitation. Particle size decreased from 2 cm to less than 425 µm for 80% of the initial mass. X-ray analysis of both fractions did not reveal the presence of α-spodumene or γ-spodumene. The coarse fraction was ground to less than 425 µm with minimal mechanical energy and mixed with the finer fraction to perform lithium extraction. The lithium extraction efficiency reached 98 wt% without the need for flotation. Some aspects of the thermodynamic behavior of the spodumene system were assessed. Results show that metastable γ-spodumene may hinder the formation of β-spodumene at lower heat treatment temperatures. Some heat-treated samples presented non-negligible γ-spodumene content and lithium extraction efficiency decreases as the γ content increases. Finally, the assumed irreversibility of the transformations was studied by analyzing heat-treated samples following long controlled-storage periods. The results show that concentrate composition is not static over the studied time. This suggests that the β formation is not as irreversible as claimed. It is recommended to avoid long periods between heat-treatment and extraction to avoid the slow conversion of β-spodumene to other allotropes, which are less susceptible to lithium extraction.
Encapsulated Limonene: A Pleasant Lemon-Like Aroma with Promising Application in the Agri-Food Industry. A Review
Authors: Ibáñez María Dolores , Sanchez-Ballester Noelia M. , Blázquez María Amparo
Published: June 2020

Limonene, mainly found as a major component in Citrus spp., has been proven to possess a valuable potential as sustainable replacement to synthetic pesticides and food preservatives. This review intends to give a clear overview of the principal emerging applications of limonene in the agri-food industry as antimicrobial, herbicidal and antioxidant agent. To successfully use limonene in a greener agri-food industry, its preservation had become a top concern for manufacturers. In order to elucidate the most efficient and sustainable manner to encapsulate limonene, the different techniques and materials tested up to the present are also reviewed. In general, encapsulation conserves and protects limonene from outside aggressions, but also allows its controlled release as well as enhances its low water solubility, which can be critical for the discussed applications. Other parameters such as scalability, low cost and availability of equipment will need to be taken into account. Further efforts would likely be oriented to the elucidation of encapsulating sustainable systems obtained by cost-efficient elaboration processes, which can deliver effective concentrations of limonene without affecting crops and food products.
Inhibitory Effects of Tangeretin, a Citrus Peel-Derived Flavonoid, on Breast Cancer Stem Cell Formation through Suppression of Stat3 Signaling
Authors: Ko Yu-Chan , Choi Hack Sun , Liu Ren , Kim Ji-Hyang , Kim Su-Lim , Yun Bong-Sik , Lee Dong-Sun
Published: June 2020

Breast cancer stem cells (BCSCs) are responsible for tumor chemoresistance and recurrence. Targeting CSCs using natural compounds is a novel approach for cancer therapy. A CSC-inhibiting compound was purified from citrus extracts using silica gel, gel filtration and high-pressure liquid chromatography. The purified compound was identified as tangeretin by using nuclear magnetic resonance (NMR). Tangeretin inhibited cell proliferation, CSC formation and tumor growth, and modestly induced apoptosis in CSCs. The frequency of a subpopulation with a CSC phenotype (CD44+/CD24−) was reduced by tangeretin. Tangeretin reduced the total level and phosphorylated nuclear level of signal transducer and activator of transcription 3 (Stat3). Our results in this study show that tangeretin inhibits the Stat3 signaling pathway and induces CSC death, indicating that tangeretin may be a potential natural compound that targets breast cancer cells and CSCs.
Extra Virgin Olive Oil Phenols Dilate the Rat Mesenteric Artery by Activation of BKCa2+ Channels in Smooth Muscle Cells
Authors: D’Agostino Rossana , Barberio Laura , Gatto MariaCarmela , Muzzalupo Innocenzo , Mandalà Maurizio
Published: June 2020

Accumulating evidence has shown the beneficial health effects of extra virgin olive oil (EVOO) consumption in reducing blood pressure and preventing the risk of developing hypertension. Some studies associate the hypotensive activity of EVOO to a minor component—the phenols. This study was designed to investigate the effects of EVOO phenols on the rat resistance mesenteric artery (MA) and to find out the possible vascular pathways involved. The experiments were carried out using a pressurized myograph, which allowed the effects of phenols on isolated MA to be tested under different conditions: (a) with endothelium removed; (b) with inhibition of nitric oxide synthase by Nω-Nitro-l-arginine methyl ester hydrochloride (l-NAME, 10−4 M) + Nω-Nitro-l-arginine (l-NNA, 10−4 M); (c) with inhibition of cyclooxygenase by indomethacin (10−5 M); (d) with inhibition of guanylate cyclase by 1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one (ODQ,10−5 M) or adenylate cyclase by 9-(Tetrahydro-2′-furyl)adenine (SQ, 10−5 M); (e) with depolarization by high potassium chloride (40 mM); and (f) with inhibition of the large conductance Ca2+–potassium channels (BKCa2+) with paxilline (10−5 M). EVOO phenols induce vasodilation of the endothelium, mediated by a direct effect on smooth muscle cells (SMC) by activation of BKCa2+ channels, an action by which phenols can regulate the vascular tone of the resistance artery. Phenols can be regarded as bioactive molecules that may contribute to the antihypertensive effects of EVOO.
Bisphosphonate-Based Molecules as Potential New Antiparasitic Drugs
Authors: Branco Santos Joice Castelo , de Melo Jonathas Alves , Maheshwari Sweta , de Medeiros Wendy Marina Toscano Queiroz , de Freitas Oliveira Johny Wysllas , Moreno Cláudia Jassica , Mario Amzel L. , Gabelli Sandra B. , Sousa Silva Marcelo
Published: June 2020

Neglected tropical diseases such as Chagas disease and leishmaniasis affect millions of people around the world. Both diseases affect various parts of the globe and drugs traditionally used in therapy against these diseases have limitations, especially with regard to low efficacy and high toxicity. In this context, the class of bisphosphonate-based compounds has made significant advances regarding the chemical synthesis process as well as the pharmacological properties attributed to these compounds. Among this spectrum of pharmacological activity, bisphosphonate compounds with antiparasitic activity stand out, especially in the treatment of Chagas disease and leishmaniasis caused by Trypanosoma cruzi and Leishmania spp., respectively. Some bisphosphonate compounds can inhibit the mevalonate pathway, an essential metabolic pathway, by interfering with the synthesis of ergosterol, a sterol responsible for the growth and viability of these parasites. Therefore, this review aims to present the information about the importance of these compounds as antiparasitic agents and as potential new drugs to treat Chagas disease and leishmaniasis.
GC-MS Composition and Olfactory Profile of Concretes from the Flowers of Four Nicotiana Species
Authors: Popova Venelina , Ivanova Tanya , Stoyanova Albena , Nikolova Violeta , Hristeva Tsveta , Zheljazkov Valtcho D.
Published: June 2020

The genus Nicotiana (Solanaceae) includes over 70 species, with a long history of traditional use; many of them are nowadays used in bioengineering, biosynthesis, molecular biology, and other studies, while common tobacco, N. tabacum L., is one of the most economically important industrial crops worldwide. Although Nicotiana species have been extensively investigated, relatively less research has focused on flowers, especially research related to obtaining aromatic products for cosmetic and perfumery use. On the other hand, there is evidence that Nicotiana flowers accumulate various secondary metabolites with a distinct aroma and biological activities, and the flowers represent a biomass available in sufficient quantities. Therefore, this study aimed to determinate the chemical composition (by GC-MS) and the olfactory profiles of a specific type of natural aromatic product (concrete), obtained from the flowers of four Nicotiana species, in a direct comparison between them. The yields of extracted concrete were sufficiently high, varying between the species, 1.4% (N. rustica L.), 2.5% (N. glutinosa L.), 1.6% (N. alata Link&Otto genotype with white flowers), 2.7% (N. alata genotype with pink flowers), 3.2% (N. tabacum, Oriental type), and 5.2% (N. tabacum, Virginia type). The major components of the obtained concretes belonged to different chemical classes: N. rustica and N. tabacum (OR), the hydrocarbons n-tetratriacontane (14.5%; 15.0%) and n-triacontane (12.1%; 13.3%), and 3-methyl-pentanoic acid (11.1%; 12.2%); N. glutinosa, the diterpenes sclareol (25.9%), 3-α-hydroxy-manool (16.3%), and 13-epimanool (14.9%); N. alata (WF), the phenylpropanoid terephthalic acid and di(2-ethylhexyl) ester (42.9%); N. alata (PF), the diterpene tributyl acetylcitrate (30.7%); and N. tabacum (FCV), the hydrocarbons n-hexacosane (12.9%) and n-pentacosane (12.9%). Each of the flower concretes revealed a characteristic odor profile. This is the first report about Nicotiana species as a source for obtaining flower concretes; these initial results about the concrete yield, olfactory profile, and chemical composition are a prerequisite for the possible processing of Nicotiana flowers into new aromatic products for use in perfumery and cosmetics. The study provides new data in favor of the potential of the four Nicotiana species as aromatic plants, as well as a possible alternative use of flowers, a valuable, but discarded, plant material in other applications.
A Co-Delivery System of Curcumin and p53 for Enhancing the Sensitivity of Drug-Resistant Ovarian Cancer Cells to Cisplatin
Authors: Guo Xinli , Fang Zhou , Zhang Min , Yang Deyu , Wang Shuyue , Liu Kehai
Published: June 2020

In order to enhance the sensitivity of drug-resistant ovarian cancer cells to cisplatin (DDP), a co-delivery system was designed for simultaneous delivery of curcumin (CUR) and p53 DNA. Firstly, the bifunctional peptide K14 composed of tumor targeting peptide (tLyP-1) and nuclear localization signal (NLS) was synthesized. A nonviral carrier (PEI-K14) was synthesized by cross-linking low molecular weight polyethyleneimine (PEI) with K14. Then, CUR was coupled to PEI-K14 by matrix metalloproteinase 9 (MMP9)-cleavable peptide to prepare CUR-PEI-K14. A co-delivery system, named CUR-PEI-K14/p53, was obtained by CUR-PEI-K14 and p53 self-assembly. Furthermore, the physicochemical properties and gene transfection efficiency were evaluated. Finally, ovarian cancer cisplatin-resistant (SKOV3-DDP) cells were selected to evaluate the effect of CUR-PEI-K14/p53 on enhancing the sensitivity of drug-resistant cells to DDP. The CUR-PEI-K14/DNA complexes appeared uniformly dispersed and spherical. The particle size was around 20–150 nm and the zeta potential was around 18–37 mV. It had good stability, high transfection efficiency, and low cytotoxicity. CUR-PEI-K14/p53 could significantly increase the sensitivity of SKOV3-DDP cells to DDP, and this effect was better as combined with DDP. The sensitizing effect might be related to the upregulation of p53 messenger RNA (mRNA), the downregulation of P-glycoprotein (P-gp) mRNA, and the upregulation of BCL2-Associated X (bax) mRNA. CUR-PEI-K14/p53 can be used as an effective strategy to enhance the sensitivity of drug-resistant ovarian cancer cells to DDP.