bluuebunny/crossref_metadata_2025 huggingface dataset:
Body Image and Disturbed Eating Attitudes and Behaviors in Sport-Involved Adolescents: The Role of Gender and Sport Characteristics
Authors: Jankauskiene Rasa , Baceviciene Miglė
Published: December 2019

Disordered eating in adolescents who participate in sports is an issue of great concern. However, very few studies have examined the prevalence of sport-related determinants of disturbed eating attitudes and behaviours (DEABs) in sport-involved adolescents. The present study aims to assess body image and DEABs in the sample of adolescents involved in a sport of different characteristics (competitive sport, leisure sport; weight-sensitive and less-weight-sensitive sport) and to compare the results with those of the controls. A total sample of 732 adolescents (437 (59.4%) were female) participated in the study. The participants ranged in age from 16 to 19 years (mean = 17.2, SD = 0.6). Study participants completed a questionnaire assessing sports characteristics, body image, disordered eating, and health-compromising eating behaviours. Analysis of covariance was used to test the differences of major study variables between controls and weight-sensitive and less-weight-sensitive leisure and competitive sports groups. There was no significant difference observed in DEABs between the sports groups. Competitive athletes reported more satisfaction with body image than controls. The girls participating in weight-sensitive leisure sports reported higher overweight preoccupation and greater DEABs compared to those participating in less-weight-sensitive leisure sports. Boys participating in weight-sensitive leisure sports reported a greater drive for muscularity-related behaviour compared to those participating in less-weight-sensitive leisure sports. There was no observed interaction between gender and weight sensitivity in the competitive sports group. Adolescents involved in a competitive sport demonstrated greater body image satisfaction and did not seem to present a greater risk for DEABs than controls. Special prevention attempts for lowering body image concerns and DEABs should be addressed for adolescents participating in a weight-sensitive leisure sports.
No Confirmed Cases of Taenia solium Taeniasis in a Group of Recently Arrived Sub-Saharan Migrants to Italy
Authors: Zammarchi Lorenzo , Tilli Marta , Mantella Antonia , Botta Annarita , Nicoletti Alessandra , García Héctor Hugo , Castillo Yesenia , Aquilini Donatella , Boccalini Sara , Bartoloni Alessandro
Published: December 2019

One-hundred and sixty-four migrants from Sub-Saharan Africa to Italy were screened with the Taenia solium specific enzyme-linked immunosorbent assay coproantigen (ELISA CoAg) and four (2.4%) were recorded as positive, but with optical density values near to the cut-off. No ELISA CoAg positive samples were confirmed by parasitological methods. Low positivity could be attributed to false positive result or cross-reaction with other Taenia species. Further studies are needed to assess the role of migration on sporadic autochthonous transmission of T. solium taeniasis/cysticercosis in Europe.
Effect of Bioactive Phytochemicals from Phlomis viscosa Poiret on Wound Healing
Authors: Yarmolinsky Ludmila , Budovsky Arie , Yarmolinsky Leonid , Khalfin Boris , Glukhman Vladimir , Ben-Shabat Shimon
Published: December 2019

Phlomis viscosa Poiret is an evergreen shrub growing in Israel, Turkey, Lebanon, and Syria with acknowledged pro-wound healing (WH) properties. In this study, we evaluated the pro-WH potential of selected compounds found in this plant. Among the pro-WH compounds (identified by us) was a combination of three chemicals—diosmin, 1-octen-3-ol, and himachala-2,4-diene which enhanced WH significantly both in in vitro and in vivo models. The determined phytochemicals combination could be used for the treatment of chronic wounds. The effect of the extracts, diosmin, 1-octen-3-ol on the secretion of pro-inflammatory cytokines, IL-6 (A) and IL-8 (B) by human dermal fibroblasts was significant (p < 0.001). In addition, the beneficial effect of extracts of P. viscosa and its phytochemicals on WH was evidenced by inhibiting the growth of several WH delaying microorganisms.
A Novel Class of Cost Effective and High Performance Composites Based on Terephthalate Salts Reinforced Polyether Ether Ketone
Authors: Dominici Franco , Puglia Debora , Luzi Francesca , Sarasini Fabrizio , Rallini Marco , Torre Luigi
Published: December 2019

Poly(ether ether ketone) (PEEK)-based nanocomposites have been realized with incorporation (0–30 wt %) of anhydrous calcium terephthalate salts (CATAS), synthetized by reaction of terephtalic acid with the metal (Ca) oxide, by means of a melt processing. Their structure, morphology, thermal, and mechanical properties have been investigated. Scanning electron microscopy observations confirmed homogeneous dispersion of nanometer-sized fillers and a toughened fracture morphology even at the higher content, while thermal characterization confirmed an unvaried thermal stability and unmodified crystalline structure of the reference PEEK matrix. A negligible nucleating effect was evidenced, while a blocking effect of the amorphous phase fraction provide composites with increased stiffness, confirmed by enhanced values of G’ and shifts of glass transition peak to higher temperatures, for restriction in chain mobility imposed by CATAS. The proposed solutions aimed to enlarge the application range of high performance costly PEEK-based composites, by using thermally stable nanofillers with limited costs and easily controllable synthesis phase.
Progress in the Synthesis of Bifunctionalized Polyhedral Oligomeric Silsesquioxane
Authors: Wang Mingyue , Chi Hong , K.S. Joshy , Wang Fuke
Published: December 2019

Polyhedral oligomeric silsesquioxane (POSS) has been considered as one of the most promising nanofillers in academic and industrial research due to its unique multifunctional nanostructure, easy functionalization, hybrid nature, and high processability. The progress of POSS has been extensive, particularly applications based on single- or multiple-armed POSS. In polymer hybrids, in order to enhance the properties, bifunctional POSS has been incorporated into the backbone chain of the polymer. This review summarizes recent developments in the synthesis, modification, and application of bifunctional POSS-containing composite materials. This includes amino-POSS, hydroxyl-POSS, aromatic ring-POSS, ether-POSS, and vinyl groups-POSS and their applications, exemplified by polyurethanes (PUs) and polyimides (PIs). In addition, the review highlights the enhancement of thermal, mechanical, and optical properties of the composites.
Development of Multi-Functional Graphene Polymer Composites Having Electromagnetic Interference Shielding and De-Icing Properties
Authors: Ha Ji-Hwan , Hong Soon-Kook , Ryu Jae-Kwan , Bae Joonwon , Park Sung-Hoon
Published: December 2019

We developed a multi-functional graphene composite with electromagnetic interference (EMI) shielding and de-icing properties. Two-dimensional graphene fillers were homogeneously dispersed in a polymer by three-roll milling. The electrical properties and percolation threshold of the graphene composites were measured with various graphene contents. The variation in the EMI shielding properties of the graphene composites with respect to the filler content was measured. The shielding efficiency improved with increasing graphene filler content. Furthermore, we conducted electrical heating tests on the graphene composites. The composites could be heated rapidly to 200 °C by electrical Joule heating with low electric power because of the high electrical conductivity of the composite. Moreover, the composite film was suitable for application in a de-icing unit because of its rapid and homogenous heating performance.
Thiol–Ene Click Reaction Initiated Rapid Gelation of PEGDA/Silk Fibroin Hydrogels
Authors: Liang Jianwei , Zhang Xiaoning , Chen Zhenyu , Li Shan , Yan Chi
Published: December 2019

In this work, poly(ethylene glycol) diacrylate (PEGDA) molecules were grafted to silk fibroin (SF) molecules via a thiol–ene click reaction under 405 nm UV illumination for the fabrication of a PEGDA/SF composite hydrogel. The composite hydrogels could be prepared in a short and controllable gelation time without the use of a photoinitiator. Features relevant to the drug delivery of the PEGDA/SF hydrogels were assessed, and the hydrogels were characterized by various techniques. The results showed that the prepared PEGDA/SF hydrogels demonstrated a good sustained-release performance with limited swelling behavior. It was found that a prior cooling step can improve the compressive strength of the hydrogels effectively. Additionally, the MTT assay indicated the prepared PEGDA/SF hydrogel is non-cytotoxic. Subcutaneous implantation of the PEGDA/SF hydrogel in Kunming mice did not induce an obvious inflammation, which revealed that the prepared PEGDA/SF hydrogel possessed good biocompatibility. Furthermore, the mechanism of the gelation process was discussed.
Chemically Denatured Structures of Porcine Pepsin using Small-Angle X-ray Scattering
Authors: Rho Yecheol , Kim Jun Ha , Min Byoungseok , Jin Kyeong Sik
Published: December 2019

Porcine pepsin is a gastric aspartic proteinase that reportedly plays a pivotal role in the digestive process of many vertebrates. We have investigated the three-dimensional (3D) structure and conformational transition of porcine pepsin in solution over a wide range of denaturant urea concentrations (0–10 M) using Raman spectroscopy and small-angle X-ray scattering. Furthermore, 3D GASBOR ab initio structural models, which provide an adequate conformational description of pepsin under varying denatured conditions, were successfully constructed. It was shown that pepsin molecules retain native conformation at 0–5 M urea, undergo partial denaturation at 6 M urea, and display a strongly unfolded conformation at 7–10 M urea. According to the resulting GASBOR solution models, we identified an intermediate pepsin conformation that was dominant during the early stage of denaturation. We believe that the structural evidence presented here provides useful insights into the relationship between enzymatic activity and conformation of porcine pepsin at different states of denaturation.
Surface Modification of Bamboo Fibers to Enhance the Interfacial Adhesion of Epoxy Resin-Based Composites Prepared by Resin Transfer Molding
Authors: Wang Dong , Bai Tian , Cheng Wanli , Xu Can , Wang Ge , Cheng Haitao , Han Guangping
Published: December 2019

Bamboo fibers (BFs)-reinforced epoxy resin (EP) composites are prepared by resin transfer molding (RTM). The influence of BFs surface modification (NaOH solution or coupling agents, i.e., KH550 and KH560) on interfacial properties of BFs/EP composites is systematically investigated. The synergistic effect of hydrolysis, peeling reaction of BFs, and the condensation reaction of hydrolyzed coupling agents are confirmed by FTIR. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) reveal that the interfacial compatibility of NaOH- and silane-modified BFs/EP composites was significantly improved. KH550-modified BFs/EP composite renders optimal tensile, flexural, and impact strength values of 68 MPa, 86 MPa, and 226 J/m. The impact resistance mechanism at the interface of BFs/EP composites was proposed. Moreover, the dynamic mechanical properties, creep behavior, and differential scanning calorimetry of BFs/EP composites have also been carried out to understand thermal stabilities. Overall, the surface-modified BFs-reinforced EP composites exhibited superior interfacial bonding.
Allylamine PECVD Modification of PDMS as Simple Method to Obtain Conductive Flexible Polypyrrole Thin Films
Authors: Texidó Robert , Borrós Salvador
Published: December 2019

In this paper, we report a one-step method to obtain conductive polypyrrole thin films on flexible substrates. To do this, substrates were modified through allylamine plasma grafting to create a high amount of reactive amine groups on PDMS surface. These groups are used during polypyrrole particle synthesis as anchoring points to immobilize the polymeric chains on the substrate during polymerization. Surface morphology of polypyrrole thin films are modified, tailoring the polyelectrolyte used in the polypyrrole synthesis obtaining different shapes of nanoparticles that conform to the film. Depending on the polyelectrolyte molecular weight, the shape of polypyrrole particles go from globular (500 nm diameter) to a more constructed and elongated shape. The films obtained with this methodology reflected great stability under simple bending as well as good conductivity values (between 2.2 ± 0.7 S/m to 5.6 ± 0.2 S/cm).
Plasma Treatment of Polymer Powder as an Effective Tool to Functionalize Polymers: Case Study Application on an Amphiphilic Polyurethane
Authors: Laurano Rossella , Boffito Monica , Torchio Alessandro , Cassino Claudio , Chiono Valeria , Ciardelli Gianluca
Published: December 2019

Plasma treatment is a widely applied, easy, fast, and highly reproducible surface modification technique. In this work powder plasma treatment was exploited to expose carboxylic groups along the backbone of a water soluble polymer. Specifically, a custom-made amphiphilic poly(ether urethane) containing Poloxamer® 407 blocks (Mw = 54,000 Da) was first synthesized and its powders were plasma treated in the presence of Acrylic Acid vapor. To maximize –COOH group exposure while preventing polymer degradation, different Ar gas flow rates (i.e., 10, 30, and 50 sccm) were investigated. Upon gas flow increase, significant polymer degradation was observed, with a 35% molecular weight reduction at 50 sccm Ar flow rate. On the other hand, the highest number of exposed carboxylic groups (5.3 × 1018 ± 5.5 × 1017 units/gpolymer) was obtained by setting gas flow at 10 sccm. Hence, a gas flow of 10 sccm turned out to be the best set-up to maximize –COOH exposure while preventing degradation phenomena. Additionally, upon plasma treatment, no detrimental effects were observed in the thermoresponsiveness of polymer aqueous solutions, which was ensured by Poloxamer® 407 blocks. Therefore, the newly developed technology here applied on an amphiphilic poly(ether urethane) could pave the way to the tailored design of a plethora of different multifunctional hydrogels.
Detecting and Mapping Slag Heaps at Ancient Copper Production Sites in Oman
Authors: Sivitskis Alexander J. , Lehner Joseph W. , Harrower Michael J. , Dumitru Ioana A. , Paulsen Paige E. , Nathan Smiti , Viete Daniel R. , Al-Jabri Suleiman , Helwing Barbara , Wiig Frances , Moraetis Daniel , Pracejus Bernhard
Published: December 2019

This study presents a new approach for detection and mapping of ancient slag heaps using 16-band multispectral satellite imagery. Understanding the distribution of slag (a byproduct of metal production) is of great importance for understanding how metallurgy shaped long-term economic and political change across the ancient Near East. This study presents results of slag mapping in Oman using WorldView-3 (WV3) satellite imagery. A semi-automated target detection routine using a mixed tuned matched filtering (MTMF) algorithm with scene-derived spectral signatures was applied to 16-band WV3 imagery. Associated field mapping at two copper production sites indicates that WorldView-3 satellite data can differentiate slag and background materials with a relatively high (>90%) overall accuracy. Although this method shows promise for future initiatives to discover and map slag deposits, difficulties in dark object spectral differentiation and underestimation of total slag coverage substantially limit its use. Resulting lower estimations of combined user’s (61%) and producer’s (45%) accuracies contextualize these limitations for slag specific classification. Accordingly, we describe potential approaches to address these challenges in future studies. As sites of ancient metallurgy in Oman are often located in areas of modern exploration and mining, detection and mapping of ancient slag heaps via satellite imagery can be helpful for discovery and monitoring of vulnerable cultural heritage sites.
Real-Time Dense Semantic Labeling with Dual-Path Framework for High-Resolution Remote Sensing Image
Authors: Wang Yuhao , Chen Chen , Ding Meng , Li Jiangyun
Published: December 2019

Dense semantic labeling plays a pivotal role in high-resolution remote sensing image research. It provides pixel-level classification which is crucial in land cover mapping and urban planning. With the recent success of the convolutional neural network (CNN), accuracy has been greatly improved by previous works. However, most networks boost performance by involving too many parameters and computational overheads, which results in more inference time and hardware resources, while some attempts with light-weight networks do not achieve satisfactory results due to the insufficient feature extraction ability. In this work, we propose an efficient light-weight CNN based on dual-path architecture to address this issue. Our model utilizes three convolution layers as the spatial path to enhance the extraction of spatial information. Meanwhile, we develop the context path with the multi-fiber network (MFNet) followed by the pyramid pooling module (PPM) to obtain a sufficient receptive field. On top of these two paths, we adopt the channel attention block to refine the features from the context path and apply a feature fusion module to combine spatial information with context information. Moreover, a weighted cascade loss function is employed to enhance the learning procedure. With all these components, the performance can be significantly improved. Experiments on the Potsdam and Vaihingen datasets demonstrate that our network performs better than other light-weight networks, even some classic networks. Compared to the state-of-the-art U-Net, our model achieves higher accuracy on the two datasets with 2.5 times less network parameters and 22 times less computational floating point operations (FLOPs).
A Novel Multi-Objective Electromagnetic Analysis Based on Genetic Algorithm
Authors: Sun Shaofei , Zhang Hongxin , Dong Liang , Cui Xiaotong , Cheng Weijun , Khan Muhammad Saad
Published: December 2019

Correlation electromagnetic analysis (CEMA) is a method prevalent in side-channel analysis of cryptographic devices. Its success mostly depends on the quality of electromagnetic signals acquired from the devices. In the past, only one byte of the key was analyzed and other bytes were regarded as noise. Apparently, other bytes’ useful information was wasted, which may increase the difficulty of recovering the key. Multi-objective optimization is a good way to solve the problem of a single byte of the key. In this work, we applied multi-objective optimization to correlation electromagnetic analysis taking all bytes of the key into consideration. Combining the advantages of multi-objective optimization and genetic algorithm, we put forward a novel multi-objective electromagnetic analysis based on a genetic algorithm to take full advantage of information when recovering the key. Experiments with an Advanced Encryption Standard (AES) cryptographic algorithm on a Sakura-G board demonstrate the efficiency of our method in practice. The experimental results show that our method reduces the number of traces required in correlation electromagnetic analysis. It achieved approximately 42.72% improvement for the corresponding case compared with CEMA.
Two-Stage Optimization Model for Two-Side Daily Reserve Capacity of a Power System Considering Demand Response and Wind Power Consumption
Authors: Dong Jun , Fu Anyuan , Liu Yao , Nie Shilin , Yang Peiwen , Nie Linpeng
Published: December 2019

Today, wind power is becoming an important energy source for the future development of electric energy due to its clean and environmentally friendly characteristics. However, due to the uncertainty of incoming wind, the utilization efficiency of wind energy is extremely low, which means the problem of wind curtailment becomes more and more serious. To solve the issue of wind power large-scale consumption, a two-stage stochastic optimization model is established in this paper. Different from other research frameworks, a novel two-side reserve capacity mechanism, which simultaneously takes into account supply side and demand side, is designed to ensure the stable consumption of wind power in the real-time market stage. Specifically, the reserve capacity of thermal power units is considered on the supply side, and the demand response is introduced as the reserve capacity on the demand side. At the same time, the compensation mechanism of reserve capacity is introduced to encourage generation companies (GENCOs) to actively participate in the power balance process of the real-time market. In terms of solution method, compared with the traditional k-means clustering method, this paper uses the K-means classification based on numerical weather prediction (K-means-NWP) scenario clustering method to better describe the fluctuation of wind power output. Finally, an example simulation is conducted to analyze the influence of reserve capacity compensation mechanism and system parameters on wind power consumption results. The results demonstrate that with the introduction of reserve capacity compensation mechanism, the wind curtailment quantity of the power system has a significant reduction. Besides, the income of GENCOs is gradually increasing, which motivates their enthusiasm to provide reserve capacity. Furthermore, the reserve capacity mechanism designed in this paper promotes the consumption of wind power and the sustainable development of renewable energy.
Understanding Thermal Impact of Roads on Permafrost Using Normalized Spectral Entropy
Authors: Zhang Chi , Zhang Hong , Zhao Fuqiang , Sun Jing
Published: December 2019

Permafrost is characterized by low temperature, and its thermal stability is key to geohydrological cycles, energy exchange, and climate regulation. Increasing engineering activities, i.e., road construction and operations, are affecting the thermal stability in permafrost regions and have already led to the degradation of permafrost and caused environmental problems. To understand the spatiotemporal influence of road construction and operations on the thermal dynamics in permafrost regions, we conducted a study in the Ela Mountain Pass where multiple roads intersect on the Qinghai–Tibet Plateau (QTP) and calculated the thermal dynamics from 2000 to 2017 using normalized spectral entropy (measuring the disorderliness of time-series data). Our results indicate that road level is a significant influencing factor, where high-level roads (expressways) exhibit stronger thermal impacts than low-level roads (province- and county-level roads). Our results also indicate that duration of operation is the most significant factor that determines the thermal impacts of roads on permafrost: the thermal impacts of the newly paved expressway are positively related to elevation, while the thermal impacts of the old expressway are positively related to less vegetated areas. The study provides an excellent method for understanding the spatiotemporal impacts of engineering activities on the temperature dynamics in permafrost regions, thereby helping policymakers in China and other countries to better plan their infrastructure projects to avoid environmentally vulnerable regions. The study also calls for advanced techniques in road maintenance, which can reduce the accumulated disturbance of road operations on permafrost regions.
Forecasting Repair Schedule for Building Components Based on Case-Based Reasoning and Fuzzy-AHP
Authors: Park Sojin , Kwon Nahyun , Ahn Yonghan
Published: December 2019

Building maintenance is closely related to the performance and sustainability of buildings. However, existing approaches to maintenance are limited in terms of estimating required repairs. Therefore, this study proposes a case-based reasoning (CBR)-based model for estimating the time when the first repair will be needed after the completion of construction, even in phases where maintenance-related information is scarce. CBR and fuzzy-analytic hierarchy process (AHP) were employed as research methodologies. A database was established by collecting 257 cases related to maintenance of apartment buildings, and attributes were extracted through literature reviews and expert interviews. Then, attributes were weighted by fuzzy-AHP and case similarities were computed by measuring the Euclidean distance. Similar cases were retrieved based on similarity scores. The model was validated via a comparison of 20 randomly selected test cases with the output of retrieved cases. The results showed that the average case similarities of 3-, 5-, 7-, and 10-nearest neighbors (NN) were 98.05%, 97.86%, 97.73%, and 97.59%, respectively, and mean absolute percentage errors for 3-, 5-, 7-, and 10-NN were mostly lower than 20%, confirming the applicability of the proposed model. The proposed method will help in the preliminary estimation of the repair time of building components.
Some Identities and Inequalities Involving Symmetry Sums of Legendre Polynomials
Authors: Wang Tingting , Qiao Liang
Published: December 2019

By using the analysis methods and the properties of Chebyshev polynomials of the first kind, this paper studies certain symmetry sums of the Legendre polynomials, and gives some new and interesting identities and inequalities for them, thus improving certain existing results.
Analytical Solution of Heat Conduction in a Symmetrical Cylinder Using the Solution Structure Theorem and Superposition Technique
Authors: Kalbasi Rasool , Alaeddin Seyed Mohammadhadi , Akbari Mohammad , Afrand Masoud
Published: December 2019

In this paper, non-Fourier heat conduction in a cylinder with non-homogeneous boundary conditions is analytically studied. A superposition approach combining with the solution structure theorems is used to get a solution for equation of hyperbolic heat conduction. In this solution, a complex origin problem is divided into, different, easier subproblems which can actually be integrated to take the solution of the first problem. The first problem is split into three sub-problems by setting the term of heat generation, the initial conditions, and the boundary condition with specified value in each sub-problem. This method provides a precise and convenient solution to the equation of non-Fourier heat conduction. The results show that at low times (t = 0.1) up to about r = 0.4, the contribution of T1 and T3 dominate compared to T2 contributing little to the overall temperature. But at r > 0.4, all three temperature components will have the same role and less impact on the overall temperature (T).
The Peptide Venom Composition of the Fierce Stinging Ant Tetraponera aethiops (Formicidae: Pseudomyrmecinae)
Authors: Barassé Valentine , Touchard Axel , Téné Nathan , Tindo Maurice , Kenne Martin , Klopp Christophe , Dejean Alain , Bonnafé Elsa , Treilhou Michel
Published: December 2019

In the mutualisms involving certain pseudomyrmicine ants and different myrmecophytes (i.e., plants sheltering colonies of specialized “plant-ant” species in hollow structures), the ant venom contributes to the host plant biotic defenses by inducing the rapid paralysis of defoliating insects and causing intense pain to browsing mammals. Using integrated transcriptomic and proteomic approaches, we identified the venom peptidome of the plant-ant Tetraponera aethiops (Pseudomyrmecinae). The transcriptomic analysis of its venom glands revealed that 40% of the expressed contigs encoded only seven peptide precursors related to the ant venom peptides from the A-superfamily. Among the 12 peptide masses detected by liquid chromatography-mass spectrometry (LC–MS), nine mature peptide sequences were characterized and confirmed through proteomic analysis. These venom peptides, called pseudomyrmecitoxins (PSDTX), share amino acid sequence identities with myrmeciitoxins known for their dual offensive and defensive functions on both insects and mammals. Furthermore, we demonstrated through reduction/alkylation of the crude venom that four PSDTXs were homo- and heterodimeric. Thus, we provide the first insights into the defensive venom composition of the ant genus Tetraponera indicative of a streamlined peptidome.
Hydro-Meteorological Characterization of Major Floods in Spanish Mountain Rivers
Authors: Morán-Tejeda Enrique , Fassnacht Steven R. , Lorenzo-Lacruz Jorge , López-Moreno Juan Ignacio , García Celso , Alonso-González Esteban , Collados-Lara Antonio-Juan
Published: December 2019

Spain, one of the most mountainous countries in Europe, suffers from frequent river flooding due to specific climatic and topographic features. Many headwaters of the largest rivers in Spain are located in mountainous areas of mid-to-high elevation. These include the Pyrenees, the Central System, and the Cantabrian mountains, that have a sustained snowpack during the winter months. Most previous research on flood generation in Spain has focused on intense rainfall events, and the role of snowmelt has been ignored or considered marginal. In this paper we present a regional-scale study to quantify the relative importance of rainfall versus snowmelt in the largest floods recorded in mountain rivers in Spain during the last decades (1980–2014). We further analyzed whether catchments characteristics and weather types may favor the occurrence of rainfall or snowmelt induced floods. Results show that in 53% of the 250 analyzed floods the contribution of rainfall was larger than 90%, and in the rest of events snowmelt contribution was larger than 10%. Floods where snowmelt was the main contributor represented only 5% of the total events. The average contribution of snowmelt represents 18% of total runoff in floods that were analyzed. The role of snowmelt in floods, rather than triggering the event, was usually amplifying the duration of the event, especially after the peak flow was reached. In general, the importance of snowmelt in floods is greater in catchments with characteristics that favor snow accumulation. However, this does not apply to floods where contribution of snowmelt was larger than 90%, which tend to occur at catchments at mid-elevations that accumulate unusual amounts of snow that melt rapidly. Floods were more frequent under both cyclonic and anticyclonic synoptic situations over the Iberian Peninsula, as well as under advection of western and eastern flows. Our results contribute to the ongoing improvement of knowledge about the role of snow in the hydrology of Spanish rivers and on the importance of mountain processes on the hydrology of downstream areas.
Applications of Bayesian Networks as Decision Support Tools for Water Resource Management under Climate Change and Socio-Economic Stressors: A Critical Appraisal
Authors: Phan Thuc D. , Smart James C. R. , Stewart-Koster Ben , Sahin Oz. , Hadwen Wade L. , Dinh Lien T. , Tahmasbian Iman , Capon Samantha J.
Published: December 2019

Bayesian networks (BNs) are widely implemented as graphical decision support tools which use probability inferences to generate “what if?” and “which is best?” analyses of potential management options for water resource management, under climate change and socio-economic stressors. This paper presents a systematic quantitative literature review of applications of BNs for decision support in water resource management. The review quantifies to what extent different types of data (quantitative and/or qualitative) are used, to what extent optimization-based and/or scenario-based approaches are adopted for decision support, and to what extent different categories of adaptation measures are evaluated. Most reviewed publications applied scenario-based approaches (68%) to evaluate the performance of management measures, whilst relatively few studies (18%) applied optimization-based approaches to optimize management measures. Institutional and social measures (62%) were mostly applied to the management of water-related concerns, followed by technological and engineered measures (47%), and ecosystem-based measures (37%). There was no significant difference in the use of quantitative and/or qualitative data across different decision support approaches (p = 0.54), or in the evaluation of different categories of management measures (p = 0.25). However, there was significant dependence (p = 0.076) between the types of management measure(s) evaluated, and the decision support approaches used for that evaluation. The potential and limitations of BN applications as decision support systems are discussed along with solutions and recommendations, thereby further facilitating the application of this promising decision support tool for future research priorities and challenges surrounding uncertain and complex water resource systems driven by multiple interactions amongst climatic and non-climatic changes.
Multi-Objective Optimal Operation of the Inter-Basin Water Transfer Project Considering the Unknown Shapes of Pareto Fronts
Authors: Xu Jianjian , Bai Dan
Published: December 2019

Studies have shown that the performance of multi-objective evolutionary algorithms depends to a large extent on the shape of the Pareto fronts of the problem. Although, most existing algorithms have poor applicability in dealing with this problem, especially in the multi-objective optimization operation of reservoirs with unknown Pareto fronts. Therefore, this paper introduces an evolutionary algorithm with strong versatility and robustness named the Multi-Objective Evolutionary Algorithm with Reference Point Adaptation (AR-MOEA). In this paper, we take two water conservancy hubs (Huangjinxia and Sanhekou) of the Hanjiang to Wei River Water Diversion Project as example, and build a multi-objective operation model including water supply, ecology, and power generation. We use the AR-MOEA, the Non-dominated Sorting Genetic Algorithm II (NSGA-II), the Multi-Objective Evolutionary Algorithm based on Decomposition (MOEA/D) and the Indicator-Based Evolutionary Algorithm (IBEA) to search the optimal solutions, respectively. We analyze the performance of four algorithms and the operation rules in continuous dry years. The results indicate that (1) the AR-MOEA can overcome the difficulty of the shape and distribution of the unknown Pareto fronts in the multi-objective model. (2) AR-MOEA can improve the convergence and uniformity of the Pareto solution. (3) If we make full use of the regulation ability of the Sanhekou reservoir in the dry season, the water supply for coping with possible continuous dry years can be guaranteed. The study results contribute to the identification of the relationship among objectives, and is valued for water resources management of the Hanjiang to Wei River Water Diversion Project.
Theoretical studies of the kaolin minerals : Electrostatic calculations
Authors: Giese R. F.
Published: December 2019

The kaolin minerals are not ideal ionic solids but, for many purposes, they can be treated as such. The classical ionic theory allows the calculation of the potential energy of these minerals. By minimizing the potential energy as a function of one or more parameters (distances, angles, etc.) one can determine hydroxyl orientations, the stability of layer stackings, strength of the interlayer bonding and the existence of hydrogen bonding. Some of these calculations suggest that fluorine exchanged for hydroxyl should radically alter the interlayer bonding. Recent experimental work confirms this.
Le fer dans les kaolins. Étude par spectrométries RPE, Mössbauer, EXAFS
Authors: Bonnin Dominique , Muller Sylvain , Calas Georges
Published: December 2019

Seven kaolins were examined. Several phases containing iron were analysed by comparison of the used spectroscopies. Mössbauer spectroscopy shows that a part of the Fe²⁺ cannot be in the structure of kaolinite. At low temperature, we observe for one sample, presence of superparamagnetic particles of hematite and goethite. For the others we detect it only a little, this implies either their quantities are low or particule sizes are very thin (<20 Å). EPR spectrum of Fe³⁺ consists in two parts :

— One attributed to a distribution of the sites of isolated Fe³⁺ with variable symmetries.

— The second gives a wide line attributed to superparamagnetic phases.

We make semi-quantitative the analysis of this wide line by comparison with the other spectroscopies. For example, EXAFS spectroscopy shows for one sample that all the iron atoms belong amorphous structure, this is possible only in a subsidiary phase of the clay. With these results, we can say that the majority of iron is in phases associated with kaolinite.
Spectre infrarouge des hydroxyles, cristallinité et énergie de cohésion des kaolins
Authors: Cruz-Cumplido Maribel , Sow Cheik , Fripiat José Jean
Published: December 2019

L'examen des spectres de vibration des oscillateurs OH situés dans l'espace interlamellaire de diverses kaolinites permet de les classer en quatre catégories suivant un degré décroissant de cristallinité. A mesure que la cristallinité décroît, la cohésion interfoliaire augmente, comme le démontre le degré de gonflement dans l'hydrazine. Les caractéristiques spectrales et la cohésion sont intimement reliées à l'orientation des vibrateurs OH. La réduction de l'angle que forment ces oscillateurs avec l'axe C* augmente la cohésion. L'orientation par ailleurs semble dépendre de la distribution des lacunes octaédriques d'un feuillet à l'autre.
Le mécanisme de la transformation thermique de la métakaolinite
Authors: Lemaitre Jacques , Léonard André J. , Delmon Bernard
Published: December 2019

A review of the most recent studies concerning the thermal transformations of metakaolinite in the range 900-1 000 °C is presented. An agreement is found between the results obtained with several physico-chemical techniques (absolute density measurements, radial electron distribution, X-Ray fluorescence, infrared spectroscopy), pointing to the transformation of metakaolinite into mullite through two parallel routes : the first one involves a complete segregation of ill crystallized silica and alumina, mullite being formed above 1 000 °C through the recombination of the segregated phases ; the second one involves the transformation into mullite without any segregation. By introducing selected mineralizers in a well-dispersed state in the metakaolinite, it is possible to direct selectively its transformation : for instance MgO promotes the complete segregation mechanism and the formation of gamma-alumina, whereas CaO promotes the direct formation of mullite.
Valorisation des argiles kaoliniques des Charentes dans le caoutchouc naturel
Authors: Yvon Jacques , Garin Philippe , Delon Jean-François , Cases Jean-Maurice
Published: December 2019

Unmodified kaolinitic clays have semi-reinforcement properties in natural rubber. The amount of kaolinite is favourable to reinforcement, the amounts of quartz and mica is prejudicial. Properties connected with crystallinity and consequently with fineness are the second reason why vulcanized products vary : these are best when filler is well crystallized.

The properties of rubbers change also according to the processing way as a function of the geologic level the kaolinite is extracted from. Wet processing ways using sodium salts give the best results when the crystallinity decreases with the amount of potassium. Dry grinding and classification in air give the best results when the crystallinity does not depend on the amount of potassium. Vulcanisation accelerators directly incorporated in the filler increase also mechanical properties.

Aminoplasts grafting leads to a product whose properties are similar to the carbon black properties. Though grafted kaolinites have weaker reinforcement properties than carbon blacks, they present two main advantages i.e. the low processing cost and the good ageing of vulcanized products.
R.P.E. de la fluorite naturelle : inventaire des ions lanthanides et autres impuretés paramagnétiques
Authors: Chatagnon Bruno , Galland Daniel
Published: December 2019

E.P.R. studies of paramagnetic centers in natural fluorite show that the great majority of these centers are substitutional lanthanide ions. No iron group ions have been observed.

E.P.R. enables us to identify the nature and charge-state of the substitutional rare-earth ions (trivalent for gadolinium, erbium, ytterbium, neodymium, cerium and dysprosium, divalent for europium, thulium and holmium). Although europium can enter the lattice as Eu⁺⁺ under sufficiently reducing crystallisation conditions, this is not the case for thulium and holmium. The divalent charge state of these ions is probably due to ionising radiation.

The presence in the crystal of a trivalent ion L⁺⁺⁺ implies a charge deficit which must be compensated. The compensating ion can form a complex with the rare-earth ion. The complexes Gd⁺⁺⁺-Na⁺, Er⁺⁺⁺-F⁻, Ce³⁺-F⁻, Nd³⁺-F⁻ have been observed.
Géochimie des transformations métasomatiques à l'origine du gisement de talc et chlorite de Trimouns (Luzenac, Ariège, France). II. Approche des conditions physico-chimiques de la métasomatose
Authors: Moine Bernard
Published: December 2019

Le gisement de Trimouns résulte de la transformation métasomatique de roches variées en talcites et chloritites. Les minéraux alumineux (micas, feldspaths des micaschistes et roches granitiques) se transforment en chlorite ; la dolomite (marbres) et une partie du quartz se transforment en talc ; le quartz est finalement dissous. Dans une première partie (Moine et al., 1982), nous avons décrit les zonalités métasomatiques, défini les réactions à chaque front et montré le comportement des différents éléments. Nous étudions ici les paramètres des équilibres fluides-minéraux mis en jeu (P, T, composition des solutions) afin de définir un modèle cohérent des conditions physico-chimiques de la métasomatose envisagée selon la théorie de Korzhinskii. Les transformations des roches silico-alumineuses sont difficilement interprétables en raison de déséquilibres probables entre le talc et la chlorite, issus de minéraux différents. L'étude porte donc principalement sur l'équilibre dolomite-talc-solution hydrothermale, en s'appuyant sur les travaux expérimentaux de Frantz et Popp (1979). On définit le domaine de stabilité du talc par rapport aux domaines des autres minéraux du système considéré. D'autres contraintes sont introduites en raison de la stabilité du sphène et en tenant compte de la simultanéité de la transformation des dolomies en talc et de la dissolution du quartz dans les colonnes issues des micaschistes. Des relations étroites sont ainsi déterminées entre les paramètres P, T et la composition des solutions. Si l'on admet que la concentration en Mg total ne dépasse pas 0,2 m, le modèle conduit à T ≃ 475 °C pour P[F] = 1 000 bars, et par extrapolation à T ≃ 425-450 °C pour P[F] = 500 bars.
La vanmeersscheite U(UO2)3(PO4)2(OH)6 • 4 H2O et la méta-vanmeersscheite U(UO2)3(PO4)2(OH)6 • 2 H2O, nouveaux minéraux
Authors: Piret Paul , Deliens Michel
Published: December 2019

Vanmeersscheite (VM) and meta-vanmeersscheite (mVM) occur as canary yellow tablets. Optically for VM : 2V(-) = 56°, np = 1.704, nm = 1.715, ng = 1.718, and for mVM : 2 V(-) = 83°, np = 1.67, nm = 1.68 et ng = 1.69. Orthorhombic system with, for VM : a = 17.06, b = 16.76, c = 7.023 Å, Z = 4, space group P2₁mn, and for mVM : a = 34.18, b = 33.88, c = 14.074 Å, Z = 32, space group Fddd. Chemical analysis by electron microprobe : VM : UO₃ 80.76, P₂O₅ 10.40, H₂O 8.84 ; mVM : UO₃ 83.24, P₂O₅ 10.20, H₂O 6.56. The crystal structure of VM has been determined by X-ray diffraction (R = 12.6 %). Structure type : phosphuranylite. Both minerals occur at Kobokobo (Kivu, Zaïre). Names are in honor of the Belgian crystallographer Maurice Van Meerssche.
Crystal structural refinement of Na-exchanged stellerite
Authors: Passaglia Elio , Sacerdoti Michele
Published: December 2019

Natural crystals of stellerite (space group Fmmm) have been Na-exchanged, therefore becoming crystals which are chemically similar to barrerite (space group Amma). Weissenberg and precession long exposure photographs revealed that the cation exchange does not cause the expected symmetry variation, the exchanged crystals still having space group Fmmm and not Amma. The X-ray structure refinement shows that Na enters the cation sites analogous to those of barrerite and the crystals remains orthorhombic. The Fmmm symmetry is exactly maintained for the framework, whereas it is only statistically maintained for the extra-framework cations owing to the random distribution of Na atoms in those sites, alternated occupancy of which in barrerite is responsible for the Amma space group.
Données chimiques sur les pegmatites potassiques de l'Ile de Batz (Finistère, France)
Authors: Chauris Louis , Corre Yvon , Cotten Joseph
Published: December 2019

Composition chimique des principaux minéraux de pegmatites potassiques de l'île de Batz : biotite, microcline, albite, muscovite, grenat, tourmaline, béryl, apatite.
Présence de kanemite dans les sédiments récents du Lac Bogoria, Rift Gregory, Kenya
Authors: Périnet Guy , Tiercelin Jean-Jacques , Barton Charles Edward
Published: December 2019

Seuls quatre silicates de sodium hydratés sont connus à ce jour dans la nature : la magadiite (Na₂ Si₁₄ O₂₉ • 11 H₂O), la makatite (Na₂ Si₄ O₉ • 5 H₂O), la kenyaite (Na₂ Si₂₂ O₄₅ • 10 H₂O) et la kanemite (Na H Si₂O₅ • 3 H₂O). Le premier minéral est relativement fréquent, rencontré en plusieurs sites d'Afrique ou d'Amérique ; les trois autres sont rares et mentionnés seulement en Afrique. La kanemite découverte dans un seul site d'Afrique occidentale, vient d'être reconnue en Afrique orientale, dans les sédiments récents du lac Bogoria au Kenya.

Les examens au microscope électronique à balayage, par diffraction des rayons X, par analyse thermopondérale, par analyse thermique différentielle et par spectrométrie d'absorption infrarouge ont montré qu'il s'agit bien du même minéral que celui décrit par Johan et Maglione (1972) et récemment synthétisé par Beneke et Lagaly (1977).

Dans les sédiments du lac Bogoria, kanemite et magadiite sont associées. Le problème de la genèse de ces deux silicates est discuté.
On the lexical diversity of grain-supply systems in the Roman East
Authors: Solonakis Nicolas
Published: December 2019

L’approvisionnement urbain en blé constituait une préoccupation majeure pour les cités grecques de l’époque hellénistique et romaine, comme pour l’ensemble des sociétés préindustrielles. Commerce et bienfaiteurs jouaient à n’en pas douter un rôle crucial dans la fluidification des marchés alimentaires, mais les mécanismes civiques et les systèmes de distributions publiques étaient également proéminents, et bien souvent responsables des interventions les plus régulières. Ceci étant dit, les charges publiques liées à l’approvisionnement en blé sont caractérisées par une considérable profusion de termes, difficilement explicable expliquée a priori. Se fondant sur un croisement de sources littéraires et épigraphiques, cet article se donne pour but de mettre en lumière les différents schémas facteurs expliquant cette variabilité terminologique, en se concentrant sur l’orient méditerranéen. Il révèle, entre autres, que cette variabilité résulte dans une large mesure du haut degré d’institutionnalisation du secteur de l’approvisionnement en grains.