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Here we present an approach to measure the surface potential distribution of specimens using scanning tunnelling potentiometry with high potential gradients and relatively low sample bias. A special design of test structures containing pre-patterned electrodes was employed. Material of interest is transferred onto test structures, so that additional material processing during the investigations can be avoided. The utility of this solution is assessed in an investigation of high–strength metallurgical graphene. A maximum potential gradient of 49.2 V/mm was obtained by applying a sample bias of 0.8 V. Values of the resistivity of graphene inclusions up to 450 Ω·μm were observed. The influence of inclusions could be reduced by performing controllable post-transfer annealing. This could remove polymer residue from the graphene surface, but may introduce additional features in the Raman spectra. Work functions of 4.68–4.70 eV were estimated using Kelvin probe force microscopy. Unlabelled Image • A method for surface potential measurement using high electric field is proposed. • The utility of this method is was shown during High Strength Metallurgical Graphene investigation. • Maximum potential gradient used was 49.2 V/mm. • Potential drop caused by residues with resistivity up to 450 Ω·μm were observed. [ABSTRACT FROM AUTHOR]

• Spin-unrestricted optimisation of pernigraniline base oligomers of polyaniline. • ESP distribution maps of the preferred positions of H 2 O, OH− and O 2 approach to PB_PANI. • OH− and O attachments perturbe local charge, bond lengths and host molecule. • IR and UV/VIS spectra attachment identification and PB_PANI properties modification. • OH− attached to N results in a very narrow energy gap and possible conducting regime. In spite of extensive investigation and applications, influence of oxygen (O), and humidity on polyaniline (PANI) behaviour is not well understood. For this reason we have performed semi-empirical quantum mechanics, and ab-initio calculations of the pernigraniline base (PNB) PANI oligomers, of various lengths, before and after approach of H 2 O, O 2 , and hydroxyl (OH−) group, and attachment of OH− and O to various molecular positions. Structure, charge and electrostatic potential distribution, relevant energies and enthalpies, infrared and electronic spectra of the PNB tetramer equilibrium conformation, and their changes induced by specific OH−, and O attachments are determined. These results provide identification of the most probable positions for O 2 and H 2 O approach to PNB_PANI, enthalpies of OH− and O attachments to them, changes of molecular properties induced by the attachments, and infrared and electronic modes that are most suitable for the attachments detection. The results are compared to the existing experimental data, and the results of similar calculations, and implications for the PNB_PANI applications are notified. [ABSTRACT FROM AUTHOR]

Abstract Bismuth electrodes are particularly interesting owing to their high hydrogen evolution overpotential and electrocatalytic activity. In this work, a novel porous bismuth electrode was prepared via an electrochemical deposition of bismuth on a porous graphite felt of high specific surface area, employing bismuth(III) oxide as reactant and a flow electrochemical cell as reactor. A solubility up to 1 mol L−1 of bismuth was obtained in basic medium using a suitable complexing agent. We solved the problems linked to the heterogeneous potential distribution in the 3D porous structure and to the formation of dendritic excrescences that led to mechanically fragile material by using a suitable flow electrochemical cell, a periodically changing current with short on-pulses and long off-pulses and by limiting the electrodeposition of Bi on the external surfaces of the felt due to diffusion. A Bi-modified electrode with high specific surface area and low bulk density was achieved using this method. Graphical abstract Unlabelled Image Highlights • A solubility up to 1 mol L−1 of bismuth was obtained in basic medium using Bis-Tris. • Electrodeposition of bismuth on graphite felt with homogeneous coating of fibers. • The formation of dendrites that led to mechanically fragile material was limited. • The material has a high surface area and a low bulk density. [ABSTRACT FROM AUTHOR]

Highlights • Yield per hectare of sweet sorghum are influence by temperature and precipitation. • Xinjiang and Inner Mongolia are suitable for planting sweet sorghum. • The 2020 and 2050 biofuel goal can be satisfied by certain scenarios in this paper. • Climate change and land-use change are critical to energy crop development plan. Abstract Biofuel from energy crops will play an important role in supplying carbon-neutral fuel for the transport sector. However, there are large uncertainties regarding energy crop development and the energy crop potential and distribution need to be evaluated more comprehensively and systematically. In this study, we propose an integrated approach using the AquaCrop model, a geographic information system approach, and a scenario analysis and we conduct a land availability assessment with multiple factors including climate change, land use, soil, topography, regional crop management, and technological improvement to shed light on the potential production, distribution, and temporal-spatial variation of land suitable for sweet sorghum production in China. We evaluate a full range of spatial scales from 1-km resolution to a national assessment in four representative concentration pathways from 2010 to 2100. The results show that most provinces can plant sweet sorghum. The most suitable provinces for sweet sorghum production are Xinjiang, Heilongjiang, Jilin, Inner Mongolia, Yunnan, and Sichuan. The biofuel potential of sweet sorghum in high-slope farmland (0.30–0.73 EJ) and marginal land (11.98–15.18 EJ) can satisfy the biofuel goal in 2020 (0.12 EJ) and 2050 (6.70–8.60 EJ). Climate change and land-use change are critical factors influencing for the current implementation and long-term planning of energy crops in China. [ABSTRACT FROM AUTHOR]

Abstract Shale oil refers to oil stored in organic-rich shale. It is an important part of unconventional oil and provides a large amount of resources. Based on the systematic study of the geological characteristics of shale oil in China's major continental basins, the geological connotation of the "sweet area (section)" in shale oil is proposed in this paper, and it refers to areas (sections) that can be preferentially explored and developed in oil-bearing shale formations under current economic and technical conditions. The formation conditions and distribution characteristics of continental shale oil in China are analyzed with a focus on the geological properties of the Triassic Yanchang Formation in the Ordos Basin, the Cretaceous Qingshankou Formation in the Songliao Basin and the Permian Lucaogou Formation of the Jimusar Sag in the Junggar Basin. It is found that the "sweet areas" of shale oil with medium-high maturation are mainly located in thick shales with a Ro greater than 0.9%, and the "sweet sections" are mainly located in the middle and lower parts of the shale formation. The geological resources of continental shale oil in the major continental basins in China are estimated to be approximately 3700 × 108 tons. The in situ conversion process (ICP) may be a key technology for the effective development of medium-to low-mature shale oil. The scale, maximum burial depth and present depth of the organic-rich shale are proposed as the three key parameters for the optimization of pilot sites by taking the Triassic Yanchang Formation in the Ordos Basin as an example. Using ICP, it is expected that the recoverable resources of China's continental shale oil will be approximately (400–500) × 108 tons. The terminology of "man-made reservoir" is proposed in this paper. In an "man-made reservoir", the overall industrial output of the "sweet areas (sections)" is formed by artificial intervention and the construction of an underground fracture network system with "man-made permeability". Continental shale oil may be another revolutionary source of unconventional oil and is expected to be first successfully produced in China. Highlights • The "sweet areas(sections)" of continental shale oil with medium-high maturation are illustrated with examples and the resources are assessed. • The formation conditions and distribution characteristics of continental shale oil in China are analyzed. • Some important concepts are proposed, including "exploring oil into source kitchen", "source rock oil", "man-made oil reservoir", etc. [ABSTRACT FROM AUTHOR]

Abstract To investigate the distribution of dinoflagellate cyst and their relationship with environmental factors, surface sediments were collected from 14 stations of Daya Bay of the South China Sea. In total, 44 cyst species and 3 uncertain taxa were identified and the total abundance ranged from 79 to 819 cysts g−1 dry weight (DW), showing a decreasing trend from the north-west to the south-east of the bay. Based on cluster analysis, three zones were identified. In Zone I (inner bay), the heterotrophic cyst dominated and warm-water species (Alexandrium minutum/affine and Gonyaulax spinifera) were observed. In Zone III (bay mouth), cyst assemblage was characterized by halophilic taxon Protoperidinium subinerme. Correlation analysis showed that seawater temperature, salinity and sediment particle size had the greatest impacts on the composition and distribution of cyst assemblage. Furthermore, several toxic species, including Lingulodinium polyedrum , Alexandrium spp. and Gymnodinium catenatum , were observed at most stations, indicating a wide distribution and potential risk of harmful algal blooms in Daya Bay. Highlights • Significant spatial distribution of dinoflagellate cyst in surface sediment was observed across the Daya Bay. • Seawater temperature, salinity, and sediment particle size had great impact on the composition and distribution of cysts. • Several toxic and harmful dinoflagellate species have only been observed as resting cyst in sediment. [ABSTRACT FROM AUTHOR]

Abstract Patterns of distant metastatic failure of endometrial cancer (EC) by specific anatomic site are not well described in the literature. In this manuscript, we evaluated the metastatic patterns of EC cancer and analysed the potential distribution of metastatic disease in this malignancy. Methods A total of 1444 women with EC were identified. Of which we extracted women with locoregional and distant recurrence or with distant recurrence alone. Women were scored based on first site of metastasis: multiple versus one site: bone, brain, lung, liver or sus diaphragmatic lymph nodes. Results 110 women developed distant metastatic disease with (n = 37(33.6%)) or without (n = 73(66.4%)) locoregional recurrence, including 39 women with exclusive first site of metastatic disease and 34 women with multiple sites of metastatic disease. When considering all women, the most common exclusive first site of metastasis was lung (42.8%). The median time to develop distant metastases was shorter after the completion of treatment for exclusive brain metastatic disease compared with other sites of metastatic− disease (7 months vs, 9 for lung, 10 for liver, 19 for bone and 27 months for sus-diaphragmatic LN; P = 0.004). The rate of 3-year overall survival was higher in the sus-diaphragmatic LN metastase group (83.3% vs 50.6% for lung, 37.3% for bone, 16.7% for brain and 0% for liver; P = 0.0059). Conclusion The present study has demonstrated the site-specific patterns of metastases. These data support current clinical practice of screening for site-specific metastatic disease after initial treatment of early stage EC based on concerning women-specific signs or symptoms. [ABSTRACT FROM AUTHOR]

Abstract The analysis of FT-IR spectra of isotactic and syndiotactic poly(N -pentenylcarbazole) (i -PPK and s -PPK) amorphous film samples are reported in the present paper. A comparison with FT-IR spectrum of a non stereoregular polyvinylcarbazole (PVK) commercial sample is also presented. Calculated vibration spectra of both i -PPK and s -PPK are obtained through the Density Functional Theory (DFT) method. Theoretical results are interpreted in terms of potential energy distribution (PED) analysis, and compared with i -PPK and s -PPK FT-IR experimental spectra. Only a few differences, due to the conformational constrain imposed by tacticity, are detected between the two fully amorphous polymer stereoisomers. Moreover, the observed differences between PPKs and PVK spectra are attributed to the presence of the alkylene linker (-(CH 2) 3 -) in PPK samples, distancing the carbazole groups to the main chain. The alkylene linker allows more flexibility to both the side and main chain of PPK samples, giving rise to new vibrational mixed modes which are not detected in PVK. [ABSTRACT FROM AUTHOR]

Abstract Paeonia ostii (Paeoniaceae), a famous traditional flowering plant, is an edible perennial shrub having medicinal uses. In recent decades, growing market demands and unprecedented damage to forests has caused severe degeneration of its natural habitat. As a result, land managers involved in conserving and restoring its habitat need to identify the environmental factors that shape its distribution. The present study predicted the potential distribution of this species and evaluated habitat suitable for it. The main environmental factors affecting this species were determined using 145 occurrence records, 30 environmental variables, MaxEnt modeling, and an analysis using ArcGIS 10.2 software. The results showed that the moderately and highly suitable habitat for P. ostii encompasses ca. 8.23 × 105 km2; the areas with a high suitability index (>0.6) for the distribution of this species were in southern Anhui, Henan (Kaifeng, Luoyang, Pingdingshan, Xuchang, and Zhengzhou), Hubei (Huanggang and Huangshi), and Shanxi (Yan'an) provinces. Annual mean temperature, mean UV-B of the lightest month, vapor pressure, and annual precipitation were the main environmental factors affecting the distribution of P. ostii. The results of this study can allow land managers to avoid wasted human effort and materials as well as the exhaustion of wild P. ostii resources that could result from the blind introduction of this species into unsuitable habitat while improving both the quality and yield of P. ostii. Highlights • Maxent modeling was used to predict the distribution of Paeonia ostii. • The moderate and highly suitable habitat for P. ostii encompass ca. 8.23 × 105 km2. • Annual mean temperature was the most critical factors shaping it distribution. [ABSTRACT FROM AUTHOR]

Abstract Climate change poses negative impacts on plant species, particularly for those of restricted ecology and distribution range. Rosa arabica Crép., an exclusive endemic species to Saint Catherine Protectorate in Egypt, has severely declined and become critically endangered in the last years. In this paper, we applied the maximum-entropy algorithm (MaxEnt) to predict the current and future potential distribution of this species in order to provide a basis for its protection and conservation. In total, 32 field-based occurrence points and 22 environmental variables (19 bioclimatic and three topographic) were used to model the potential distribution area under current and two future representative concentration pathways (RCP2.6 and RCP8.5) for the years 2050 and 2070. Annual temperature, annual precipitation and elevation were the key factors for the distribution of R. arabica. The response curves showed that this species prefers habitats with an annual temperature of 8.05–15.4 °C, annual precipitation of 36 to 120 mm and elevation range of 1571 to 2273 m a.s.l. Most of the potential current suitable conditions were located at the middle northern region of Saint Catherine. Prediction models under two future climate change scenarios displayed habitat range shifts through the disappearance of R. arabica in sites below 1500 m a.s.l., an altitudinal range contraction at 1500–2000 m and possible expansions towards higher elevation sites (2000–2500 m a.s.l.). Our findings can be used to define the high priority areas for reintroduction or for protection against the expected climate change impacts and future modifications. Highlights • MaxEnt modeling is a key guide for predicting current and future distribution of endangered species. • The ecological niche of Rosa arabica is mainly affected by annual temperature, annual precipitation and elevation. • R. arabica favors high elevated and cold moist sites within St. Catherine Protectorate of South Sinai in Egypt. • At global warming scenarios (CCSM4: RCP2.6 and RCP8.5), R. arabica displayed habitat range shift. • Reinforcements of the extant populations and assisted migrations can be planned [ABSTRACT FROM AUTHOR]

Abstract The influence of variations in the Si fin shape on the electrical properties of junctionless transistors (JLTs) was investigated through two-dimensional Poisson equation numerical simulations at different doping concentrations. Stronger gate coupling in a triangular fin channel was observed, arising from suppression of the variation in the conduction threshold voltage with increasing doping concentration, compared to JLTs with rectangular fin channels. The potential distribution in the channel cross-section shows a less varied potential at the bottom of a triangular channel than at the bottom of a rectangular channel, and supports the result that triangular channels are less sensitive to variations in channel doping concentration. Graphical abstract Unlabelled Image Highlights • The performance of junctionless transistors (JLT) was investigated with fin shapes. • The impact of fin shapes was studied with numerical simulations. • V th variation with doping concentration N d is suppressed in triangular channels. • Heavily doped JLTs are more vulnerable with change of fin shapes. • Stronger gate coupling in triangular fin is observed with potential distributions. [ABSTRACT FROM AUTHOR]

Highlights • Climate change will modify the extent and location of suitable areas for species. • Climatic niche breadth is a valuable tool to predict the impact of global warming. • For five of the six species, suitable habitat was predicted to decline. • The species most affected will be the range-restricted species. Abstract The impacts of global warming on the spatial extent and location of suitable habitat can be examined through spatially explicit projections of climatic niches. We modeled the climatic niche of six oaks (Q. agrifolia, Q. cedrosensis, Q. chrysolepis, Q. devia, Q. palmeri and Q. peninsularis), some rare and others widely distributed, occurring within the Baja California Peninsula, Mexico, and projected future distributions under two contrasting scenarios of global warming. We also estimated the breadth of the climatic niche of each species and associated it with current and future distributions. We found that climate warming will modify the distribution of suitable habitat for the six oak species, with considerable variation in changes among species. We observed that the breadth of climate niche is related to the potential geographic distribution of the species and that the loss of area under future scenarios of global warming is significantly correlated with the climatic niche size. To keep pace with climate change, oak populations will need to colonize new areas, because a large part of their present ranges will not retain suitable climatic conditions. The oaks are dominant elements in the Mediterranean-climate region and pine-oak forests of the Baja California Peninsula, so changes in their distributions will probably affect other species that closely interact with them. Further studies on the demography and ecological interactions of these oaks are recommended to refine predictions concerning effects of climate change and to identify conservation management options. [ABSTRACT FROM AUTHOR]

Highlight • Under DC voltage, surface charge indicates polarity effect. • Increasing the voltage amplitudes led to an increase of the surface charge density. • Corona voltage and the charging time for both polarities rise, the amount of charges increases linearly. • Relationship between amount of surface charges and number of photons have been carried out using corona camera. Abstract The objective of the present study is to investigate the surface charge measurement on the surface of polymeric insulator under AC and DC voltages experimentally. According to the test results, increasing the voltage amplitudes led to an increase of the surface charge density, the voltage application duration was also extended. During the tests, it was observed that as the corona voltage and the charging time for both polarities rise, the amount of charges increases linearly. The results show that more surface charge was deposited by negative corona charging when compared with positive corona charging. Also in this paper, the effect of the corona variations on the amount of surface charge have been investigated. For this purpose, relationship between amount of surface charges and number of photons have been carried out using corona camera. Moreover, attempt was made to investigate the effects of surface charges on potential and electric field distribution along polymeric insulator under AC and DC voltages using computer simulations based on finite element method (FEM). The present paper was conducted to study the effects of magnitude, polarity, and location of surface charges on surface potential distribution along the insulator. [ABSTRACT FROM AUTHOR]

Abstract There are different approaches to solve the three-dimensional (3D) resistivity model. In this research, a new modeling technique has been developed to solve 3D potential distribution in a resistor network. This method uses the Kirchhoff's law for discretizing a resistor network. This different approach for the 3D resistivity modeling helps to describe an arbitrary 3D model using a resistor network. This method has no singularity constraint, although there is no need to apply any singularity removal techniques. The resistor network can be used for any electrode configuration. The potential distributions at all nodes are simultaneously solved for each injection source. Sensitivity matrix and potential distribution in both models are compared. Experiments with various physical models and numerical models show the similarity of the method with traditional resistivity modeling. Comparing the result of this approach with other methods shows better sensitivity away from edges. Furthermore, a parallel programming technique is used to improve the processing time. Flexibility and extensibility to build any resistivity model make this approach a powerful modeling tool in 2D and 3D electrical resistivity forward modeling. [ABSTRACT FROM AUTHOR]

Abstract Background/purpose Severely uneven occlusal attrition is thought to play an important role in the occurrence of spontaneous vertical root fracture (VRF), a frequent problem among Chinese people. This study evaluated the influence of occlusal slope related to uneven attrition on the root stress condition. Materials and methods A finite element model of the mandibular first molar was established. Two different occlusal slope patterns were simulated in 5 models: (A) sound tooth, (B) 0.5–1.5 mm and (C) 2–3 mm attrition increased buccally, and (D) 0.5–1.5 mm and (E) 2–3 mm attrition increased distally. A static load of 200 N was applied vertically or angled at 45° to the longitudinal axis. The von Mises stress was evaluated. Results Under vertical loading, more stress was transferred from the cervical to the middle root with attrition, especially the mesial root, while stress declined with attrition under oblique loading. Stress was mainly distributed in the buccal surface and mesial root with vertical loading, or in the lingual surface and distal root with oblique loading. The maximum von Mises with oblique loading was significantly higher than with vertical loading. Conclusion Uneven occlusal attrition made the middle of the mesial root bear more stress, increasing fracture risk under vertical load. This finding suggests that timely restoration of the sloped occlusal morphology in teeth with severe attrition should be recommended to prevent VRFs. Lateral loading was not a risk factor of typical vertical root fractures, but the high stress could cause distal root cervical fracture. [ABSTRACT FROM AUTHOR]

Highlights • The evaluated models are able to predict the potential occurrence of an invasive species. • The Hasse diagram technique proves to be useful to compare machine learning methods. • A specific combination of machine learning methods is superior to a single model. • The random combination of models can be inferior to the output of a single model. Abstract We tested four machine learning methods for their performance in the classification of mosquito species occurrence related to weather variables: support vector machine, random forest, logistic regression and decision tree. The objective was to find a method which showed the most accurate model for the prediction of the potential geographical distribution of Aedes japonicus japonicus , an invasive mosquito species in Germany. The evaluation of the model trainings was conducted using derivations of a confusion matrix. Furthermore, we introduced two quality indices, 'selectivity' and 'exactness', for the evaluation of the spatial simulation, visualised through the Hasse diagram technique. From the evaluation results we can conclude that a specific combination of two to three models performs better in predicting the potential distribution of the mosquito species than a single model or the random combination of models. [ABSTRACT FROM AUTHOR]

Abstract Lattice Boltzmann method is an effective tool for depicting all transport phenomena governed by advection-diffusion-reaction mechanisms. In the present study, five different cathode catalyst layers of PEM fuel cells with dissimilar morphologies are stochastically reconstructed. The agglomerates of carbon black particles are considered as ellipsoids which can have different level of stretching. The reactive air flow through the reconstructed catalyst layers is simulated by 3D lattice Boltzmann agglomerate modeling for the first time. Species distributions in the pore region, electrical potential distribution in the electrolyte film, and current density distribution at the interface of catalyst layer and membrane are depicted and analyzed. The results of this study show that oxygen and water vapor mole fraction variation is unsmooth and disturbed; and by increasing of ellipsoid stretching, this unsmooth and disturbed manner becomes more severe. Besides, the water content of the electrolyte film remains at its initial value mostly at the top of upper agglomerates while higher water content is observed where the agglomerates are closer to each other. Moreover, the catalyst layer in which ellipsoidal agglomerates have the highest level of stretching provides the maximum average current density. Graphical abstract Image 1 Highlights • Reactive flow in 5 electrodes is simulated by lattice Boltzmann agglomerate model. • Distribution of species, e-potential, water content, current density is analyzed. • Case with highest stretching parameter has the highest average current density. • Catalyst layer structure affects surface area vs effective diffusivity trade-off. [ABSTRACT FROM AUTHOR]

Abstract An open source compact and general tool, implemented in OpenFOAM including a novel solver with a new boundary condition and post-processing utilities, is derived to enable calculations of local current and potential distributions in electrochemical systems with activated or resistive electrodes and also leakage currents in the case of a bipolar connection. The algorithm allows the calculations for a given local potential in any electrode, for a fixed cell potential difference and also for a current flowing through the cell under galvanostatic control. In order to validate the algorithm, a detailed comparison between the suggested strategy with experimental results and some simplified theoretical models is made. It was concluded that the proposed mathematical treatment is reliable for the modelling of these electrochemical systems due to the good agreement between theoretical and experimental values with a mean relative percent error of 8.8 ± 2.1% for the current distribution for the whole set of experiments. Highlights • An open source algorithm was validated with theoretical and experimental results. • A multiregion approach avoids current conservation at electrodes as constrain. • The increase in current produces a less uniform current distribution. • Feeding by the middle point decrease the leakage current. • Resistive electrodes affect negatively the reactor performance. [ABSTRACT FROM AUTHOR]

• Wild boars produce negative impacts in South America. • Ecological niche modelling was used to predict potential wild boar distribution in South America. • Most ecoregions in South America have suitable conditions to sustain wild boar populations. • Suitable area occupied 85% of Atlantic Forest and 61.3% of Cerrado biodiversity hotspots. • An alarming large number of protected areas are currently or potentially affected by the species. • Control measures should be adopted to control wild boar impacts on biodiversity. Wild pigs, including wild boar (Sus scrofa) and feral domestic pig (Sus scrofa domestica), are associated with negative impacts in their native and introduced ranges. We compiled wild pig occurrence reports and utilized Maximum Entropy modelling to predict their potential distribution in ecoregions overlaying Argentina, Brazil, Bolivia, Chile, Uruguay and Paraguay. An analysis of their observed and potential distributions was carried out in relation to four biodiversity hotspots and 3766 protected areas to estimate the number of units and percent area currently and potentially invaded. Among biodiversity hotspots, Atlantic Forest, Cerrado, and Chilean Winter Rainfall-Valdivian Forests included 44.7% of wild pig records. The proportion of suitable area was 85% in Atlantic Forest, 61.3% in Cerrado, 37.5% in Chilean Winter Rainfall-Valdivian Forests, and 5.6% in Tropical Andes. The number of protected areas with known wild pig presence was led by Uruguay (100%), followed by Chile (20.3%), Argentina (15.8%), Paraguay (9.5%), Bolivia (6.5%), and Brazil (4.7%). The proportion of protected areas with predicted wild pig presence was highest in Uruguay (100%), followed by Paraguay (72.6%), Brazil (58.0%), Argentina (57.4%), Chile (42.2%), and Bolivia (35.9%). Our work represents the first assessment of wild pig potential distribution in South America and highlights the potentially devastating impacts of wild pigs on the regional biodiversity and national conservation targets, especially at mega-diverse areas. We present a dynamic web application that can be readily consulted by scientists, managers and decision makers to improve wild pig control and risk mitigation actions in the study region. [ABSTRACT FROM AUTHOR]

This paper proposes an electrochemical chloride extraction (ECE) model for cement-based materials that considers coupled multi-ion transport, adsorption and dissolution. Then ECE tests were designed and conducted to validate the proposed ECE model. Based on the proposed ECE model, parametric studies were conducted. Parametric studies show that the chloride binding capacity of cement pastes depends heavily on the contents of aluminate ferrite monosulfate (AFm) and alumina ferrite tri-sulfate (AFt). Moreover, the content compositions of free, absorbed and chemically-bound chloride ions vary with the types of chloride salts, i.e., the cations in the chloride salts. Moreover, temperatures within the range between 5 °C and 40 °C pose negligible influences on the ECE process. Current densities and durations are the most influential factors affecting the ECE process, which are thus the main parameters to be determined for the design of ECE. In addition, the chloride ion content distributions are bell curves during the ECE process and peaks exist within the concrete cover. Therefore, it is recommended to adopt three chloride ion contents as controlling indexes for the ECE process, i.e., 1) the chloride ion content at the surface of steel bars, 2) the average chloride ion content within the concrete cover and 3) the peak chloride ion content within the concrete cover. [ABSTRACT FROM AUTHOR]

Digital data enable researchers to obtain fine-grained temporal information about social interactions. However, positional measures used in social network analysis (e.g., degree centrality, reachability, betweenness) are not well suited to these time-stamped interaction data because they ignore sequence and time of interactions. While new temporal measures have been developed, they consider time and sequence separately. Building on formal algebra, we propose three temporal equivalents to positional network measures that incorporate time and sequence. We demonstrate how these temporal equivalents can be applied to an empirical context and compare the results with their static counterparts. We show that, compared to their temporal counterparts, static measures applied to interaction networks obscure meaningful differences in the way in which individuals accumulate alters over time, conceal potential disconnections in the network by overestimating reachability, and bias the distribution of betweenness centrality, which can affect the identification of key individuals in the network. [ABSTRACT FROM AUTHOR]

An important step in managing invasive species is determining the factors responsible for their current and potential distribution, especially when species distribution is climatically determined like in Reynoutria taxa case. The main aim of this paper was to integrate all available distribution data of the Reynoutria taxa in SE Europe and to predict in which habitats and along which corridors its future spread can be expected. Distribution data of the Reynoutria taxa were obtained from extensive field studies in the period from 2006 to 2016, as well as from the literature and herbarium sources. A total of 4081 localities in Serbia and the Kosovo region, Montenegro, Slovenia, Croatia, Bosnia and Herzegovina, Bulgaria and Romania have been recorded, most frequently in riparian and human-made habitats. Ecologically suitable ranges for the Reynoutria taxa were predicted using the MaxEnt program and 19 bioclimatic variables which were derived from the WorldClim data set. Results of this study showed that the most frequent Reynoutria taxa in SE Europe are R. japonica var. japonica and hybrid R. × bohemica . The most suitable geographical areas for R. japonica and R. sachalinensis are mostly located in the north, while for R. × bohemica the central part of SE Europe is suitable. The precipitation of the warmest quarter had a high influence on the potential distribution modelling of these closely related species. Potential distribution modelling revealed R. × bohemica ’s high temperature tolerance in different seasons with high durability of drought (up to 60 mm per year less precipitation than parental species). Moreover, this research predicts which areas are most likely to be invaded, and makes suggestions where to focus management efforts for survey and removal of these invaders, especially in protected areas. According to the future climate analysis R. japonica and R. × bohemica could expand their range in riparian habitats up to 30–40%. Consequently, invasion in Slovenia’s and Croatia’s rivers requires urgent preventative measures. This study provides empirical evidence that these plants could become widespread throughout SE Europe within 25 years under the current trend and emphasizes that regionally specific management plans should be implemented to prevent further spread of these taxa. [ABSTRACT FROM AUTHOR]

In order to enhance the ion adsorption capacity and ion selective ability of electrode materials, carbon nanotube/polypyrrole (CNT/PPy) composites doped with chloride (Cl − ) and dodecyl benzene sulfonate (DBS - ) were used for capacitive deionization (CDI) process, respectively. Seven types of symmetric and asymmetric CDI cells based on the obtained composite electrodes and CNT electrode were assembled and tested. The experimental results indicated that the desalination performance for CDI cells typically depended on the potential of zero charge (PZC) of the electrodes and the potential distribution of the cells. The PZC of the CNT, CNT/PPy-Cl and CNT/PPy-DBS electrodes were measured to be 0 V, −0.1 V and 0.4 V vs. saturated calomel electrode, respectively. In the applied potential of 1.2 V, the largest effective working potential of 1.2 V and the highest adsorption capacity of 35.46 mg/g were found based on the CNT/PPy-Cl (anode)‖CNT/PPy-DBS (cathode) cell, in which the PZCs were all outside of the polarization window of the corresponding electrodes. While a diminished effective working potential and desalination performance can be observed when one of the PZCs at least was within the polarization window of the respective electrode. This work provides an effective approach for optimizing electrode configuration based on PZC analysis. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) related decreases in muscle strength may result from both central and peripheral factors. However, the effect of PD on the neuromuscular system, such as motor unit activation properties, remains unclear. The purpose of the present study was to compare the spatial distribution pattern of electromyographic activity during sustained contractions in healthy subjects and PD patients. Twenty-five female PD patients and 25 healthy age-matched female control subjects performed ramp submaximal contractions during an isometric knee extension from 20% to 80% of the maximal voluntary contraction (MVC). To evaluate alterations in the spatial electromyography (EMG) potential distribution, normalized root mean square (RMS), modified entropy, coefficient of variation, and correlation coefficients were calculated from multi-channel surface electromyography at 10% force increments. The comparison between PD and healthy subjects revealed that, during increased force exertions, PD patients exhibited less change in normalized RMS, modified entropy, coefficient of variation, and pattern of spatial EMG distribution. These data showed that the heterogeneity and the changes in the activation pattern are smaller in the PD patients than in healthy subjects. This finding may be associated with central adaptation and/or peripheral changes in PD patients. [ABSTRACT FROM AUTHOR]

Culicoides orientalis was first recorded from Sikkim, in the year 1963, but no evidence based disease outbreak were available. In the last 50 years, 260 Bluetongue disease outbreaks caused by Culicoides species have been evidenced from India. Moreover, in recent years with increase of average temperature worldwide and increase in longevity of arthropod vectors like Culicoides along with a geographical range shift to new suitable warmer regions has increased the potentiality of vector borne disease outbreak throughout the world. The Himalayan range of Sikkim in India is a biodiversity hotspot and is extremely sensitive to such global climate changes. An attempt has been made to evaluate the altitude, climate and environmental data on selected study sites of Sikkim for a period of two years (2014–2015) for discerning potential distribution of C.orientalis in this region. The altitude, temperature, precipitation and potential distribution range maps of C. orientalis showed the areas of highest species abundance within the altitudinal range of 550–1830 m, with some species extending its range up to 3750 m, with average precipitation of 2010–2590 mm and mean temperature of 11–18 °C. The Maximum Entropy Modelling (MaxEnt) and the Jackknife test of the MaxEnt model further revealed that the major contributing factors governing C. orientalis distribution are annual precipitation (78.8%), followed by precipitation of driest quarter (8.3%) and mean temperature of the warmest quarter (3.3%). Accuracy of the study was evaluated by the area under the curve (AUC = 0.860). The Biplot on F 1 –F 2 axes (N = 16, α = 0.05) in the PCA showed the linear depiction of all the variables considered in our study, major contributors were annual precipitation, precipitation of driest quarter and mean temperature of warmest quarter being the primary factors governing species distribution, as analogous to results of the MaxEnt model. This study would help in developing strategies for monitoring and managing surveillance programmes to control the chances of disease spread to livestock animals and also validate the predictions on the eventual spread of the vector midges to higher altitudes of Sikkim. [ABSTRACT FROM AUTHOR]

While imaging individual atoms can routinely be achieved in high resolution transmission electron microscopy, visualizing the potential distribution of individually charged adsorbates leading to a phase shift of the probing electron wave is still a challenging task. Low-energy electrons (30 – 250 eV) are sensitive to localized potential gradients. We employed low-energy electron holography to acquire in-line holograms of individual charged impurities on free-standing graphene. By applying an iterative phase retrieval reconstruction routine we recover the potential distribution of the localized charged impurities present on free-standing graphene. [ABSTRACT FROM AUTHOR]

The electrochemical corrosion of 907A low alloy steel under epoxy coating exposed to natural seawater was investigated by the wire beam electrode (WBE) and electrochemical impedance spectroscopy (EIS) techniques, and the correlations of the current distribution and the EIS characteristics for local defect areas of the coating were discussed. It was found that there were close corresponding relationships among the potential distribution, the current distribution and the EIS characteristics in the whole or local areas of the WBE. Each electrode of the WBE had a distinctive electrochemical corrosion characteristic during the coating degradation process. The EIS characteristics of the WBE were dominated by the substrate corrosion process of the most serious coating defect. Polarity reversals of the single electrodes under epoxy coating can be found, but the causes of the phenomena were different from each other. [ABSTRACT FROM AUTHOR]

South Africa has a major problem with invasive plant species. Many species have long residence times, are well established, and have large invasive ranges, whereas others are still in the early stages of invasion. Predicting the full extent of invasions for species that have only recently started spreading is important for guiding management strategies. Ailanthus altissima is a widespread invasive species in many parts of the world. Although it has had a long residence time in South Africa, it is yet to replicate the extent of invasiveness and major impacts reported for the species in other parts of its adventive range. We mapped the countries in which A . altissima has been reported and evaluated the invasion status of the species in each (i.e. the position of the species on the introduction-naturalization-invasion continuum as conceptualized by Richardson and Pyšek, 2012). We then mapped the current distribution in more detail for South Africa. The species is known to be present in at least 51 countries and is invasive in 23 countries. Ailanthus altissima is present in all South African provinces except Limpopo and is most common and abundant in the Western Cape, Gauteng, Eastern Cape, and the Free State. We applied species distribution modelling using global distribution data to determine parts of the world, and in particular regions within South Africa, that are climatically suitable for the species. Large parts of Africa are potentially invasible by this species. Seven regions in South Africa were identified as high-risk areas for invasion by A . altissima . The species is already far too widespread in South Africa for eradication at the national scale to be feasible. A national strategy for managing the species should focus on: 1) early detection and rapid response in areas identified as climatically suitable and where the species is not already present; and 2) local and regional-scale initiatives based on objective prioritization in terms of feasibility of management success and asset protection. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFCs) have the outstanding ability to transform the chemical energy contained in organic matter directly to electrical energy. Unfortunately, they give only low cell voltage at maximum power. Connecting several MFCs electrically in series inside the same reactor may be a way to increase the cell voltage, but experimental attempts have shown poor efficiency for such single-electrolyte stacks. The present study uses numerical modelling to understand the behaviour of single-electrolyte MFC stacks and to assess possible ways to improve it. The numerical model was validated by comparison with two experimental MFCs that produced 0.85 ± 0.05 mW each at 0.23 V cell voltage. Connected in series in a common electrolyte, the stack produced only 0.7 mW at 0.21 V, while, in theory, 1.7 mW could be reached at 0.47 V. The model showed that the drastic power loss was due to ionic short-circuiting, which may, however, be an interesting phenomenon to be exploited for designing an electro-microbial snorkel. The model also showed that decreasing the anode-cathode distance, increasing the distance between the MFCs or using baffles between them could optimize the single-electrolyte stack to produce up to 80% of the theoretical maximum power. Nevertheless, such designs are appropriate only for specific applications, e.g. biosensing. The model further suggests that benthic MFCs could be effectively connected in series. [ABSTRACT FROM AUTHOR]

• Electrochemical impedance of porous electrodes. • Investigation of relationship between pore shape and electrochemical impedance. • 3D simulation using finite element method showing potential distributions. • Inclination angle of impedance spectrum increases for shallow pores. • Inclination angle observable with simulated porous enzyme electrodes. Porous electrodes are widely used in many applications, such as enzyme electrodes, energy devices, and electrosynthesis. However, evaluation of porous electrodes using electrochemical impedance spectroscopy, one of the most promising methods for determining electrochemically relevant structural information, is challenging. Thus, in this study, impedance spectra were simulated using a three-dimensional, finite element method-based model for porous electrodes. The shape of the electrode pore was varied, and the effect on the resulting impedance spectrum was analyzed. The results indicated that for certain pore shapes, such as wide and shallow cylinders, a three-dimensional model was required to obtain accurate results. However, for narrow and deep cylindrical pores, a classical one-dimensional approximation was sufficiently accurate, and a 45º inclined line was observed in the impedance spectra with high frequencies, even when a three-dimensional model was employed. Moreover, wide and shallow or narrowing pores result in a higher inclination angle, whereas widening or branching pores result in a lower inclination angle. These features were also observed when charge transfer and diffusion processes were considered in terms of a mediator-type enzyme electrode reaction. [Display omitted] [ABSTRACT FROM AUTHOR]

An Au/SiO 2 /Si MOS structure was fabricated by the thermal oxidation of H-terminated Si(100) surface and the electrode formation, and hard X-ray photo-emission spectroscopy (HAXPES) measurements of MOS structure under the different applied bias conditions were performed systematically to investigate the potential distribution such as the band bending in the MOS structure and the chemical bonding features in the region near the Au/SiO 2 interface. And, the measured energy position of HAXPES signals originating from the Au electrode, SiO 2 , and Si substrate were compared with the calculation results of potential change for ideal MOS structure in consideration of SiO 2 thickness and impurity concentration of Si substrate. [ABSTRACT FROM AUTHOR]

Even though researchers have paid a great deal of attention to wetland loss and status, the actual extent of wetland loss on a global scale, especially the loss caused directly by human activities, and the actual extent of currently surviving wetlands remains uncertain. This paper simulated the potential distribution of global wetlands by employing a new Precipitation Topographic Wetness Index (PTWI) and global remote sensing training samples. The results show earth would have approximately 29.83 million km 2 of wetlands, if humans did not interfere with wetland ecosystems. By combining datasets related to global wetlands, we found that at least 33% of global wetlands had been lost as of 2009, including 4.58 million km 2 of non-water wetlands and 2.64 million km 2 of open water. The areal extent of wetland loss has been greatest in Asia, but Europe has experienced the most serious losses. Wetland-related datasets suffer from major inconsistencies, and estimates of the areal extent of the remaining global wetlands ranged from 1.53 to 14.86 million km 2 . Therefore, although it is challenging, thematic mapping of global wetlands is necessary and urgently needed. [ABSTRACT FROM AUTHOR]

We propose and study a novel O2O business model for real-estate purchases, called Information-based Real-Estate Platform (iREP in short). The new model leverages the power of Internet and mobile Apps for connecting directly the customers via a federation of human expert agents which work in a loosely coupled relation and on-demand basis. The unique features of this O2O model include: the use of mobile Apps in engaging customers together with selected agents, better resource sharing and allocation of the human agents, and relatively higher-speed of transactions by liberating the restrictions of agents. Unlike the traditional sales models where agents were dedicated to specific property agency companies, this one-stop model enables wider range of products to be marketed to all the potential buyers, leading to better matching between demands and supplies. iREP is modeled using BPR modeling tool for illustrating its model structure and the values that flow within the federation framework among the parties involved. Then the value model is subject to business process re-engineering simulation, for demonstrating how the dynamic processed are streamlined, thereby creating net values for both the developers and the end-consumers. [ABSTRACT FROM AUTHOR]

To improve the resolution capabilities of MCP, numerical simulation of the MTF of MCP has been made. Solving the electron trajectory equation, we obtain the potential distribution of MCP, and then obtain the electron trajectory in MCP. On this basis, a group of MTF curves are plotted by varying the tilt angle, the channel diameter, and the output end spoiling depth, individually. The simulation results show that in a moderate range a larger the tilt angle, a smaller the channel diameter, and a deeper the output end spoiling depth can improve the resolution of MCP significantly, according to the state of the art. Research on the effect of the above parameters on the resolution properties of MCP will provide a theoretical support for developing MCP with high resolution and further improving the resolution of image intensifiers. [ABSTRACT FROM AUTHOR]

Local species distribution models (SDMs) were constructed for three of the most harmful invasive alien plant species ( Fallopia spp., Solidago spp. and Heracleum mantegazzianum ) in the Kokořínsko Protected Landscape Area (Czech Republic), using Natura 2000 habitat types and other environmental conditions as predictors for the SDMs. Presence or absence data (recorded by field mapping) was entered into the SDMs and used to predict the potential distribution of particular species. Here, we critically evaluate the accuracy of the models and assess their applicability for natural resource protection. Variables such as habitat and soil type tend to dictate the current distribution of Solidago spp., while distance from roads and water corridors and elevation are important for Fallopia spp. distribution. For Solidago spp., ‘generalised boosted models’ and ‘generalised additive models’ were considered the most suitable algorithms. For Fallopia spp., however, the predictive power of the models tended to be weak, while the number of localities was too low for SDMs in the case of H. mantegazzianum . The number of initial localities containing invasive alien species was an important factor for making significant predictions of potential distribution. In general, the predictive power of the models was too low when using less than 10 localities; for good predictive power at the local scale, we suggest that at least 100 localities/100 km 2 are used. [ABSTRACT FROM AUTHOR]

The electrical-double-layer (EDL)-based adsorption models for ionic surfactants propose all surfactant heads ideally aligned in the Stern layer, creating a single surface potential which controls the distribution of counterions within the diffuse layer. Despite their successful application to many surfactant systems, these models exhibit a noticeable shortcoming when it comes to explaining the larger surface excess of ionic surfactants at air|water interface than oil|water interface. Experiments and computation simulations have already shown that some surfactant head groups tend to immerse into the deeper layers of interfacial water at high surface coverage. Such an immersion alters the surface potential distribution and characteristics of EDL. However, a theoretical study of this phenomenon is not available yet. This paper presents a useful modeling approach to quantification of the surfactant immersion. We combined the ionic surfactant adsorption models with the theory of equilibrium adsorption constant. We modified several non-ionic surfactant adsorption models for describing the ionic surfactant adsorption by accounting for their immersion. The adsorption parameters were determined by fitting to experimental adsorption data and were then used along with the theory of equilibrium adsorption constants to successfully explain the reported difference in the surface excess of sodium dodecyl sulphate (SDS) at air|water and oil|water interfaces. The surfactant immersion directly affected the intermolecular interaction parameter which was closely related with the adsorption energy of surfactants at the interfaces. The collaborative effect of these two parameters was also found to be responsible for the immersion of surfactants and shaping their different concentration profiles across various liquid|fluid interfaces. The immersion of surfactants was found to enhance their surface adsorption effectively. Also, our model successfully elucidated why SDS adsorption at the oil|water interface unexpectedly decreases as the hydrophobicity of the oil phase increases. [ABSTRACT FROM AUTHOR]

Placing electrical charges on nanomaterials is a means to extend their functional capabilities in nanoelectronics and sensoring applications. This paper explores the effect of charging nitrogen bases cytosine (Cyt) and adenine (Ade) via protonation on their noncovalent interaction with carbon nanotubes (CNT) using quantum chemical calculations performed at the M05-2X/6-31++G** level of theory alongside with a molecular graphics method. It is shown that the protonation of the bases causes threefold increase of the interaction energy in the CNT·Cyt·H + and СNT·Ade·H + complexes as compared to the CNT complexes formed with neutral bases. There is also some shortening of the base-CNT distance by ca 0.13 Ǻ. The visualization of the electrostatic potential distribution with the molecular graphics reveals that the positive potential due to the protonated bases extends to a cylindrical domain of the nanotube segment adjacent to the base binding site. Furthermore, subtraction of the electrostatic potential maps of the protonated bases from the maps of their complexes with CNTs reveals an area of negative potential on the CNT surface, which reflects the location of the adsorbed base. The positive charge transfer of ca 0.3 e from the protonated bases to the CNT strengthens the interaction in the CNT·Cyt·H + and СNT·Ade·H + complexes. The analysis of the frontier orbitals shows that the LUMOs of the complexes mainly reside on the CNT, while the HOMOs spread over both components of each complex. The observed effects may facilitate the design of nanomaterials involving nitrogen bases and CNTs. [ABSTRACT FROM AUTHOR]

In this paper, the Duffing oscillator with three different forms of asymmetrical double-well potentials is considered. We mainly focus our attention on how the three different forms of asymmetrical potentials can affect the dynamical behaviors of the bursting oscillations generated by double-well Duffing oscillator. Applying the dynamical mechanism of bursting oscillations, we carry out an analysis on the bifurcation diagram and dynamics of the system when the asymmetry parameter and amplitude of the external force vary. Our results show that the period, amplitude and numbers of spikes depend on the value of the control parameter. [ABSTRACT FROM AUTHOR]

We report on a technique to determine in-operando transport properties of Organic Light Emitting Diodes (OLEDs). Two types of OLEDs that solely differ in the emission layer but obviously exhibit a different potential distribution are investigated in this study. If the emission layer consists of the isomer TH-A a large shift in onset voltage can be observed in case of layer thickness variation of the emission layer. In case of the isomer TH-B a thickness variation has no impact on the onset voltage. Therefore the voltage developments per layer are determined with the help of IV measurements on a set of devices with varying layer thickness. From an empirical point of view the voltage behaviour in each layer follows a simple power law. A drift-diffusion model is developed that well describes the current density dependent evolution of coefficient and exponent of the power law. From the model we are able to derive the carrier injection mechanism into the respective layer as well as the injection barrier height. Also the carrier mobility is determined. Finally we are able to show that the existence of a large injection barrier can not explain the observed onset voltage shifts in case of TH-A. Instead an electric field at or close to the interface is necessary to describe the TH-A behaviour. [ABSTRACT FROM AUTHOR]

In this paper, a two-dimensional analytical model is established for the Buried Oxide Double Step Silicon On Insulator structure proposed by the authors. Based on the two-dimensional Poisson equation, the analytic expressions of the surface electric field and potential distributions for the device are achieved. In the BODS (Buried Oxide Double Step Silicon On Insulator) structure, the buried oxide layer thickness changes stepwise along the drift region, and the positive charge in the drift region can be accumulated at the corner of the step. These accumulated charge function as the space charge in the depleted drift region. At the same time, the electric field in the oxide layer also varies with the different drift region thickness. These variations especially the accumulated charge will modulate the surface electric field distribution through the electric field modulation effects, which makes the surface electric field distribution more uniform. As a result, the breakdown voltage of the device is improved by 30% compared with the conventional SOI structure. To verify the accuracy of the analytical model, the device simulation software ISE TCAD is utilized, the analytical values are in good agreement with the simulation results by the simulation software. That means the established two-dimensional analytical model for BODS structure is valid, and it also illustrates the breakdown voltage enhancement by the electric field modulation effect sufficiently. The established analytical models will provide the physical and mathematical basis for further analysis of the new power devices with the patterned buried oxide layer. [ABSTRACT FROM AUTHOR]

Ornithodoros ticks as vectors of pathogens have had serious implications on public health. In China, these ticks are mainly distributed among arid and semiarid areas of the northwest. To improve prevention and risk control of such tick-borne diseases, suitable habitats for four Ornithodoros tick species found in China were predicted using a Maxent model. These habitats were identified based on the global geographic distributions that the tick is known to inhabit. For this study, literature reviews were conducted for each Ornithodoros species at a global level based on published studies and available online databases. Study results showed that high species suitability was primarily concentrated in northwest China for the species Ornithodoros lahorensis , O. papillipes , and O. tartakovskyi , with O. capensis limited to a predicted distribution along the coast in southeastern China. Under future climate conditions Representative Concentration Pathway scenario 4.5 and 8.5, suitable habitats for O. lahorensis , O. papillipes , and O. tartakovskyi were predicted to shift and would likely increase the potential of the species to spread, and O. capensis would reduce compared with the current climatic conditions. For all four species, temperature and precipitation were the main variables influencing distribution. • Northwest China was high species suitability areas for Ornithodoros. • O. capensis limited to a predicted distribution along the coast in southeastern China. • Using atmospheric and ground-derived data to assess the environmental niche. [ABSTRACT FROM AUTHOR]

In recent years, Italian cocklebur (Xanthium italicum Moretti) and stab cocklebur (X. spinosum Linnaeus) has become rapidly expanded invasive plants in Xinjiang, China. Some of their mature fruits set down on the dry ground, some might fall into the water, and the other might remain on the branches of the mother plant until next spring. The habitats that seeds are exposed to in the winter will affect the seed germination in the following year. To assess their invasiveness, predict their potential distribution area, and provide scientific guidance for effective prevention and control of the invaders, four kinds of natural winter habitats that the seeds might be exposed to in Xinjiang were simulated in our study. In conclusion, seeds of X. italicum has a better over-winter performance than that of X. spinosum. We suggested that province-wide monitor of the X. italicum in Xinjiang should be carried out. However, X. spinosum should be mainly monitored in moderate and arid habitats at lower latitude and altitude regions. • Seeds of Xanthium italicum can overwinter successfully in Xinjiang of China, whatever they fall on ground, fall into water, or stay on branches of their mother plants. • Seeds of Xanthium spinosum staying on their mother plants or falling on ground can safely overwinter in Xinjiang of China, but hardly can the seeds falling into the water. • In view of seed germination characteristics of the two invaders, it is suggested that different strategies should be adopted to monitor them. [ABSTRACT FROM AUTHOR]

Herein, differences in intermolecular interactions between the two positional hetero-substituents-aromatic isomers i.e. 4-hydroxycoumarin (4-HC) and 7-hydroxycoumarin (7-HC) are studied by terahertz (THz) spectroscopy and density functional theory (DFT) calculations. Combining the THz spectra with potential energy distribution (PED) results to analyze characteristic absorption peaks and vibrational modes, we found that the characteristic absorption peaks of 4-HC and 7-HC are dominated by intermolecular interactions, including electrostatic interactions and van der Waals (vdW) interactions. Comparing the electrostatic potential (ESP) and vdW potential distribution between 4-HC and 7-HC, we deduced that the differences in the THz spectra can be possibly attributed to the difference in vibrational modes and intermolecular hydrogen bonds between 4-HC and 7-HC due to the different position of hydroxyl group. Results demonstrate that THz spectroscopy combined with the above analysis methods is an effective way to analyse intermolecular interactions and identify biomolecules with similar structures. [ABSTRACT FROM AUTHOR]

In this article a mathematical model of multi-tip field cathode is presented. The field emitters periodic system for rectangular lattice serves as a field cathode on a flat substrate. A flat anode is parallel to the substrate. A unit cell with the individual field emitter is considered to calculate the electrostatic potential distribution. The effect of the field emitter on the distribution of the electrostatic potential is simulated as the effect of a finite charged line that is located at the axis of the system. The variable separation method is used to solve the boundary-value problem. The three-dimensional analytical solution for the Laplace/Poisson equation is obtained in the Cartesian coordinate system. The potential distribution is represented as an Fourier expansion, and the expansion coefficients are found in an explicit form. Values of the emission characteristics are determined by FowlerNordheim equation. The effect of electrostatic shielding on the emission characteristics is presented. [ABSTRACT FROM AUTHOR]

This study systematically investigated the potential of mitigating sulfide induced sewer concrete corrosion by surface washing. Washing interrupted the corrosion activity of concrete coupons by increasing the surface pH and decreasing the H 2 S uptake rates (SUR). The SUR recovered to the level prior to washing within 60–140 days. The slowest recovery rate was from the most severely corroded coupon. However, no significant difference was observed for concrete mass loss of the washed and unwashed coupons after 54 months. The results suggest that frequent washing at short intervals of a few months might be needed to control corrosion over a long term. [ABSTRACT FROM AUTHOR]

In game theory the interaction among players obligates each player to develop a belief about the possible strategies of the other players, to choose a best-reply given those beliefs, and to look for an adjustment of the best-reply and the beliefs using a learning mechanism until they reach an equilibrium point. Usually, the behavior of an individual cost-function, when such best-reply strategies are applied, turns out to be non-monotonic and concluding that such strategies lead to some equilibrium point is a non-trivial task. Even in repeated games the convergence to a stationary equilibrium is not always guaranteed. The best-reply strategies analyzed in this paper represent the most frequent type of behavior applied in practice in problems of bounded rationality of agents considered within the Artificial Intelligence research area. They are naturally related with the, so-called, fixed-local-optimal actions or, in other words, with one step-ahead optimization algorithms widely used in the modern Intelligent Systems theory. This paper shows that for an ergodic class of finite controllable Markov games the best-reply strategies lead necessarily to a Lyapunov/Nash equilibrium point. One of the most interesting properties of this approach is that an expedient (or absolutely expedient) behavior of an ergodic system (repeated game) can be represented by a Lyapunov-like function non-decreasing in time. We present a method for constructing a Lyapunov-like function: the Lyapunov-like function replaces the recursive mechanism with the elements of the ergodic system that model how players are likely to behave in one-shot games. To show our statement, we first propose a non-converging state-value function that fluctuates (increases and decreases) between states of the Markov game. Then, we prove that it is possible to represent that function in a recursive format using a one-step-ahead fixed-local-optimal strategy. As a result, we prove that a Lyapunov-like function can be built using the previous recursive expression for the Markov game, i.e., the resulting Lyapunov-like function is a monotonic function which can only decrease (or remain the same) over time, whatever the initial distribution of probabilities. As a result, a new concept called Lyapunov games is suggested for a class of repeated games. Lyapunov games allow to conclude during the game whether the applied strategy provides the convergence to an equilibrium point (or not). The time for constructing a Potential (Lyapunov-like) function is exponential. Our algorithm tractably computes the Nash, Lyapunov and the correlated equilibria: a Lyapunov equilibrium is a Nash equilibrium, as well it is also a correlated equilibrium. Validity of the proposed method is successfully demonstrated both theoretically and practically by a simulated experiment related to the Duel game. [ABSTRACT FROM AUTHOR]

Climate change is becoming an increasing threat to biodiversity. Consequently, methods for delineation, establishment and management of protected areas must consider the species' future distribution in response to future climate conditions. Biodiversity in high altitude semiarid regions may be particularly threatened by future climate change. In this study we assess the main environmental variables that best explain present day presence of the world's highest elevation woodlands in the South American Altiplano, and model how climate change may affect the future distribution of this unique ecosystem under different climate change scenarios. These woodlands are dominated by Polylepis tarapacana (Rosaceae), a species that forms unique biological communities with important conservation value. Our results indicate that five environmental variables are responsible for 91% and 90.3% of the present and future P. tarapacana distribution models respectively, and suggest that at the end of the 21st century, there will be a significant reduction (56%) in the potential habitat for this species due to more arid conditions. Since it is predicted that P. tarapacana 's potential distribution will be severely reduced in the future, we propose a new network of national protected areas across this species distribution range in order to insure the future conservation of this unique ecosystem. Based on an extensive literature review we identify research topics and recommendations for on-ground conservation and management of P. tarapacana woodlands. [ABSTRACT FROM AUTHOR]

The use of scanning thermal microscopy (SThM) and Kelvin probe force microscopy (KPFM) to investigate silicon nanowires (SiNWs) is presented. SThM allows imaging of temperature distribution at the nanoscale, while KPFM images the potential distribution with AFM-related ultra-high spatial resolution. Both techniques are therefore suitable for imaging the resistance distribution. We show results of experimental examination of dual channel n -type SiNWs with channel width of 100 nm, while the channel was open and current was flowing through the SiNW. To investigate the carrier distribution in the SiNWs we performed SThM and KPFM scans. The SThM results showed non-symmetrical temperature distribution along the SiNWs with temperature maximum shifted towards the contact of higher potential. These results corresponded to those expressed by the distribution of potential gradient along the SiNWs, obtained using the KPFM method. Consequently, non-uniform distribution of resistance was shown, being a result of non-uniform carrier density distribution in the structure and showing the pinch-off effect. Last but not least, the results were also compared with results of finite-element method modeling. [ABSTRACT FROM AUTHOR]

The presence of invasive species has been predicted using species distribution models (SDMs) and presence-only data to assist environmental management. However, SDMs include substantial uncertainty and the lack of absence data hampers the use of probabilistic predictions. A non-statistical theoretical basis able to deal with uncertainty on which to model invasive species distributions with presence-only data is thus needed. Fuzzy set theory satisfies these two requirements but has been little used. This paper proposes a fuzzy modelling approach for predicting invasive species potential distributions using presence-only data and SDMs to support the design of cost-effective monitoring schemes. The invasion of Gunnera tinctoria (Molina) Mirbel (Giant rhubarb) in the island of São Miguel (the Azores, Portugal) is used as case study. The latter involved the prediction of the potential distribution of the invader using MaxEnt and the selection of priority areas for monitoring the spread of the invader in case of scarcity of resources. In addition, MaxEnt was used within a traditional (non-fuzzy) approach, unable to quantity and report on uncertainty. The results of the fuzzy and non-fuzzy approaches are compared and their differences discussed, thus highlighting the potential benefits of using fuzzy set theory for species distribution modelling and management. [ABSTRACT FROM AUTHOR]

Since the Moreno's et al. (2005) work, no study was done to update the distribution patterns of Stenella dolphins in the southwestern Atlantic Ocean. Ecological niche modeling was used to redefine the distribution patterns of Stenella dolphins in this area of Atlantic Ocean. Maximum entropy method (Maxent) was employed to generate models using a set of environmental variables as explanatory variables of the location records obtained by sighting and accidental captures. All ecological niche models performed returned AUC values > 0.9. Areas with high environmental suitability for pantropical spotted dolphin ( Stenella attenuata ), Clymene dolphin ( Stenella clymene ) and spinner dolphins ( Stenella longirostris ) are found in warm (> 25 °C) and deep waters (≥ 1000 m). High environmental suitability for Atlantic spotted dolphin ( Stenella frontalis ) seems to occur between 20.5°S and 30°S in the southeastern Brazilian coastal waters. The projected maps of species distributions showed patterns closely related to environmental changes at a fine spatial scale and added valuable information about the offshore limits of those oceanic species. The results suggest that the different species of Stenella have distinct environmental requirements in the southwestern Atlantic Ocean. [ABSTRACT FROM AUTHOR]