bluuebunny/crossref_metadata_2025 huggingface dataset:
An Efficient Indexing Approach for Continuous Spatial Approximate Keyword Queries over Geo-Textual Streaming Data
Authors: Deng Ze , Wang Meng , Wang Lizhe , Huang Xiaohui , Han Wei , Chu Junde , Zomaya Albert Y.
Published: January 2019

Current social-network-based and location-based-service applications need to handle continuous spatial approximate keyword queries over geo-textual streaming data of high density. The continuous query is a well-known expensive operation. The optimization of continuous query processing is still an open issue. For geo-textual streaming data, the performance issue is more serious since both location information and textual description need to be matched for each incoming streaming data tuple. The state-of-the-art continuous spatial-keyword query indexing approaches generally lack both support for approximate keyword matching and high-performance processing for geo-textual streaming data. Aiming to tackle this problem, this paper first proposes an indexing approach for efficient supporting of continuous spatial approximate keyword queries by integrating m i n - w i s e signatures into an AP-tree, namely AP-tree + . AP-tree + utilizes the one-permutation m i n - w i s e hashing method to achieve a much lower signature maintenance costs compared with the traditional m i n - w i s e hashing method because it only employs one hashing function instead of dozens. Towards providing a more efficient indexing approach, this paper has explored the feasibility of parallelizing AP-tree + by employing a Graphic Processing Unit (GPU). We mapped the AP-tree + data structure into the GPU’s memory with a variety of one-dimensional arrays to form the GPU-aided AP-tree + . Furthermore, a m i n - w i s e parallel hashing algorithm with a scheme of data parallel and a GPU-CPU data communication method based on a four-stage pipeline way have been used to optimize the performance of the GPU-aided AP-tree + . The experimental results indicate that (1) AP-tree + can reduce the space cost by about 11% compared with MHR-tree, (2) AP-tree + can hold a comparable recall and 5.64× query performance gain compared with MHR-tree while saving 41.66% maintenance cost on average, (3) the GPU-aided AP-tree + can attain an average speedup of 5.76× compared to AP-tree + , and (4) the GPU-CPU data communication scheme can further improve the query performance of the GPU-aided AP-tree + by 39.4%.
A Modified Methodology for Generating Indoor Navigation Models
Authors: Lewandowicz Elżbieta , Lisowski Przemysław , Flisek Paweł
Published: January 2019

Automatic methods for constructing navigation routes do not fully meet all requirements. The aim of this study was to modify the methodology for generating indoor navigation models based on the Medial Axis Transformation (MAT) algorithm. The simplified method for generating corridor axes relies on the Node-Relation Structure (NRS) methodology. The axis of the modeled structure (corridor) is then determined based on the points of the middle lines intersecting the structure (polygon). The proposed solution involves a modified approach to the segmentation of corridor space. Traditional approaches rely on algorithms for generating Triangulated Irregular Networks (TINs) by Delaunay triangulation or algorithms for generating Thiessen polygons known as Voronoi diagrams (VDs). In this study, both algorithms were used in the segmentation process. The edges of TINs intersected structures. Selected midpoints on TIN edges, which were located in the central part of the structure, were used to generate VDs. Corridor structures were segmented by polygon VDs. The identifiers or structure nodes were the midpoints on the TIN edges rather than the calculated centroids. The generated routes were not zigzag lines, and they approximated natural paths. The main advantage of the proposed solution is its simplicity, which can be attributed to the use of standard tools for processing spatial data in a geographic information system.
Diachronic Reconstruction and Visualization of Lost Cultural Heritage Sites
Authors: Rodríguez-Gonzálvez Pablo , Guerra Campo Ángel , Muñoz-Nieto Ángel , Sánchez-Aparicio Luis , González-Aguilera Diego
Published: January 2019

Cultural heritage (CH) documentation is essential for the study and promotion of CH assets/sites, and provides a way of transmitting knowledge about heritage to future generations. The integration of the fourth dimension into geospatial datasets enables generating a diachronic model of CH elements, namely, a set of three-dimensional (3D) models to represent their evolution in various historical phases. The enhanced four-dimensional (4D) modeling (3D plus time) pursues a better understanding of the CH scenario, enriching historical hypotheses as well as contributing to the conservation and decision-making process. Although new geomatic techniques have reduced the amount of fieldwork, when put together, the geometric and temporal dimensions imply the interpretation of heterogeneous historical information sources and their integration. However, this situation could reach a critical point when the study elements are no longer present. The main challenge is to harmonize the different historical and archaeological data sources that are available with the current remains in order to graphically rebuild and model the lost CH assets with a high degree of reliability. Moreover, 4D web visualization is a great way to disclose the CH information and cultural identity. Additionally, it will serve as a basis to perform simulations of possible future risks or changes that can happen during planned or hypothetical restoration processes. This paper aims to examine the study case of a diachronic reconstruction by means of a mobile laser system (MLS) and reverse modeling techniques for a lost urban CH element: the citadel or Alcázar gate of Ávila. Within this aim, the final model is evaluated in terms of the consistency of the historical sources to assess its suitability considering the constructive interpretations that are required to integrate heterogenous data sources. Moreover, geometric modeling is evaluated regarding the current remains and its surroundings. Finally, a web 4D viewer is presented for its dissemination and publicity. This paper is an extended and improved version of our paper that was published in the 2018 ISPRS Technical Commission II Symposium, Riva del Garda, Italy, 3–7 June 2018.
Diverse Visualization Techniques and Methods of Moving-Object-Trajectory Data: A Review
Authors: He Jing , Chen Haonan , Chen Yijin , Tang Xinming , Zou Yebin
Published: January 2019

Trajectory big data have significant applications in many areas, such as traffic management, urban planning and military reconnaissance. Traditional visualization methods, which are represented by contour maps, shading maps and hypsometric maps, are mainly based on the spatiotemporal information of trajectories, which can macroscopically study the spatiotemporal conditions of the entire trajectory set and microscopically analyze the individual movement of each trajectory; such methods are widely used in screen display and flat mapping. With the improvement of trajectory data quality, these data can generally describe information in the spatial and temporal dimensions and involve many other attributes (e.g., speed, orientation, and elevation) with large data amounts and high dimensions. Additionally, these data have relatively complicated internal relationships and regularities, whose analysis could cause many troubles; the traditional approaches can no longer fully meet the requirements of visualizing trajectory data and mining hidden information. Therefore, diverse visualization methods that present the value of massive trajectory information are currently a hot research topic. This paper summarizes the research status of trajectory data-visualization techniques in recent years and extracts common contemporary trajectory data-visualization methods to comprehensively cognize and understand the fundamental characteristics and diverse achievements of trajectory-data visualization.
Out of Plumb Assessment for Cylindrical-Like Minaret Structures Using Geometric Primitives Fitting
Authors: Alsadik Bashar , Abdulateef Nagham Amer , Khalaf Yousif Husain
Published: January 2019

Cultural heritage documentation and monitoring represents one of the major tasks for experts in the field of surveying, photogrammetry and geospatial engineering. Cultural heritage objects in countries like Iraq and Syria have suffered from intentional destruction or demolition during the last few years. Furthermore, many heritage sites in the mentioned places have an added religious value, and were either destroyed or are still in danger. Mosques, churches and shrines typically include one or multiple tower structures, and these towers or minarets are in many cases cylindrical-like objects. Because of their tall and relatively thin body, and adding in their age of construction, observing their inclination or out of plumb is of high importance. Accordingly, it is highly necessary for the continuous monitoring and assessment of their preservation and restoration. In this paper, we suggest an out of plumb assessment procedure using a geometric primitives least squares fitting technique, namely, cylinders, cones, and 3D circles. The approach is based on reconstructing a dense point cloud of the minaret tower which is scaled to reality by control points. Accordingly, the out of plumb is computed by fitting one of the mentioned 3D primitives to the minaret point cloud where its major axis orientation is computed. Two experimental tests of heritage objects in Iraq are presented: the lost heritage of the minaret al Hadbaa in the city of Mosul (1173 AD) and an existing inclined minaret of the religious shrine of Imam Musa AlKadhim in Baghdad (1058 AD). The results show the efficiency of the suggested methodology where the out of plumb is computed as 0.45m±1cm for the shrine minaret and 1.90m±10cm for the model of the minaret al Hadbaa.
Exosomes and the Future of Immunotherapy in Pancreatic Cancer
Authors: Batista Ines A. , Melo Sonia A.
Published: January 2019

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease, associated with a late diagnosis and a five-year survival rate of 8%. Currently available treatments fall short in improving the survival and quality of life of PDAC patients. The only possible curative option is still the surgical resection of the tumor. Exosomes are extracellular vesicles secreted by cells that transport proteins, lipids, and nucleic acids to other cells, triggering phenotypic changes in the recipient cells. Tumor cells often secrete increased amounts of exosomes. Tumor exosomes are now accepted as important players in the remodeling of PDAC tumor stroma, particularly in the establishment of an immunosuppressive microenvironment. This has sparked the interest in their usefulness as mediators of immunomodulatory effects for the treatment of PDAC. In fact, exosomes are now under study to understand their potential as nanocarriers to stimulate an immune response against cancer. This review highlights the latest findings regarding the function of exosomes in tumor-driven immunomodulation, and the challenges and advantages associated with the use of these vesicles to potentiate immunotherapy in PDAC.
The Neonatal Screening Program in Brazil, Focus on Sickle Cell Disease (SCD)
Authors: Silva-Pinto Ana C. , Alencar de Queiroz Maria Cândida , Antoniazzo Zamaro Paula Juliana , Arruda Miranete , Pimentel dos Santos Helena
Published: January 2019

Since 2001, the Brazilian Ministry of Health has been coordinating a National Neonatal Screening Program (NNSP) that now covers all the 26 states and the Federal District of the Brazilian Republic and targets six diseases including sickle cell disease (SCD) and other hemoglobinopathies. In 2005, the program coverage reached 80% of the total live births. Since then, it has oscillated between 80% and 84% globally with disparities from one state to another (>95% in São Paulo State). The Ministry of Health has also published several Guidelines for clinical follow-up and treatment for the diseases comprised by the neonatal screening program. The main challenge was, and still is, to organize the public health network (SUS), from diagnosis and basic care to reference centers in order to provide comprehensive care for patients diagnosed by neonatal screening, especially for SCD patients. Considerable gains have already been achieved, including the implementation of a network within SUS and the addition of scientific and technological progress to treatment protocols. The goals for the care of SCD patients are the intensification of information provided to health care professionals and patients, measures to prevent complications, and care and health promotion, considering these patients in a global and integrated way, to reduce mortality and enhance their quality of life.
On the Design and Implementation of an IoT based Architecture for Reading Ultra High Frequency Tags
Authors: dos Santos Yago Luiz , Dias Canedo Edna
Published: January 2019

Internet of Things comprises an increasing number of interconnected smart devices, where communication happens anytime, anywhere, reducing hardware costs and the complexity of the architectures. Reading Radio Frequency Identification tags using ultra high frequency is a high-cost activity because of its infrastructure and the radio frequency identification tag reading device for these frequencies. This work proposes an architecture that enables the cost reduction of Radio Frequency Identification tag reading equipment operating ultra high frequency in an infrastructure using cloud computing and microservices. The use of cloud computing and microservices was necessary due to scalability and the management of large volumes of data that can be generated by reading Radio Frequency Identification tags using ultra high frequency and the complexity of the architecture related to the theme of this work. The proposed architecture was applied in a real case study to verify its adherence and compliance. The proposed architecture can be used in any system that presents similar characteristics to the one proposed in this work. In scenarios where reading distance is a fundamental requirement, it is necessary to include an external antenna for better results. Other practical experiments will be carried out to evaluate the use of the proposed architecture in other contexts related to the use of Internet of Things and reading of Radio Frequency Identification tags.
Using Opinion Mining in Context-Aware Recommender Systems: A Systematic Review
Authors: Sundermann Camila Vaccari , Domingues Marcos Aurélio , Sinoara Roberta Akemi , Marcacini Ricardo Marcondes , Rezende Solange Oliveira
Published: January 2019

Recommender systems help users by recommending items, such as products and services, that can be of interest to these users. Context-aware recommender systems have been widely investigated in both academia and industry because they can make recommendations based on a user’s current context (e.g., location and time). Moreover, the advent of Web 2.0 and the growing popularity of social and e-commerce media sites have encouraged users to naturally write texts describing their assessment of items. There are increasing efforts to incorporate the rich information embedded in user’s reviews/texts into the recommender systems. Given the importance of this type of texts and their usage along with opinion mining and contextual information extraction techniques for recommender systems, we present a systematic review on the recommender systems that explore both contextual information and opinion mining. This systematic review followed a well-defined protocol. Its results were based on 17 papers, selected among 195 papers identified in four digital libraries. The results of this review give a general summary of the current research on this subject and point out some areas that may be improved in future primary works.
Energy Efficiency and Renewable Energy Management with Multi-State Power-Down Systems
Authors: Andro-Vasko James , Bein Wolfgang , Ito Hiro
Published: January 2019

A power-down system has an on-state, an off-state, and a finite or infinite number of intermediate states. In the off-state, the system uses no energy and in the on-state energy it is used fully. Intermediate states consume only some fraction of energy but switching back to the on-state comes at a cost. Previous work has mainly focused on asymptotic results for systems with a large number of states. In contrast, the authors study problems with a few states as well as systems with one continuous state. Such systems play a role in energy-efficiency for information technology but are especially important in the management of renewable energy. The authors analyze power-down problems in the framework of online competitive analysis as to obtain performance guarantees in the absence of reliable forecasting. In a discrete case, the authors give detailed results for the case of three and five states, which corresponds to a system with on-off states and three additional intermediate states “power save”, “suspend”, and “hibernate”. The authors use a novel balancing technique to obtain optimally competitive solutions. With this, the authors show that the overall best competitive ratio for three-state systems is 9 5 and the authors obtain optimal ratios for various five state systems. For the continuous case, the authors develop various strategies, namely linear, optimal-following, progressive and exponential. The authors show that the best competitive strategies are those that follow the offline schedule in an accelerated manner. Strategy “progressive” consistently produces competitive ratios significantly better than 2.
Metabolic Syndrome and Its Associations with Components of Sarcopenia in Overweight and Obese Older Adults
Authors: Mesinovic Jakub , McMillan Lachlan B. , Shore-Lorenti Catherine , De Courten Barbora , Ebeling Peter R. , Scott David
Published: January 2019

Ageing, obesity and the metabolic syndrome (MetS) may all contribute to poor muscle health (sarcopenia). This study aimed to determine the cross-sectional associations between MetS (International Diabetes Federation classification) and sarcopenia (revised European Working Group on Sarcopenia in Older People definition) in 84 overweight and obese older adults. Components of sarcopenia included muscle strength (hand grip and leg extension), physical performance (stair climb test and short physical performance battery (SPPB), including gait speed and repeated chair stands time), muscle mass (appendicular lean mass (ALM), dual-energy X-ray absorptiometry), muscle size (peripheral quantitative computed tomography-determined calf and forearm cross-sectional area (CSA)) and muscle quality (muscle density and strength normalised to lean mass). Waist circumference was associated with greater muscle size, but poorer leg extension strength, chair stands and stair climb time, gait speed, SPPB scores and muscle quality measures (all p < 0.05). MetS was positively associated with ALM and forearm muscle CSA, and negatively associated with muscle quality measures and chair stands time (all p < 0.05). MetS is associated with larger muscle size, yet poorer muscle quality in overweight and obese older adults. Assessments of muscle function and quality should be considered for obese older adults and those with MetS.
Patient-Reported Outcome Measures for Patients with Diabetes Mellitus Associated with Foot and Ankle Pathologies: A Systematic Review
Authors: Ortega-Avila Ana Belen , Cervera-Garvi Pablo , Ramos-Petersen Laura , Chicharro-Luna Esther , Gijon-Nogueron Gabriel
Published: January 2019

Background: Diabetes mellitus (DM) is a chronic and complex disease, which is a major cause of morbidity and mortality and affects all age groups. It commonly produces secondary effects on the foot, often making daily activities impossible. Patient-reported outcome measures (PROMs) provide a standardised method of obtaining patients’ outlooks on their functional status and wellbeing. Although many instruments have been proposed for obtaining data on persons with DM whose feet are affected by the disease, in many cases the psychometric properties of the instrument have yet to be established. The principal objective of our review was to identify PROMs specific for patients with DM affecting the foot and ankle and to evaluate the psychometric properties and methodological quality of these instruments. Methods: In this systematic review, we investigate studies (published in English or Spanish) based on the use of one or more PROMs specific to foot and ankle pathologies for patients with DM (type I or II). To do so, the databases PubMed, Scopus, CINAHL, PEDro and Google Scholar were searched for studies that analysed psychometric or clinimetric properties in this respect. These were assessed according to Terwee or COSMIN criteria. Results: Of the 1016 studies identified in the initial search, only 11 were finally included in the qualitative review. Analysis according to Terwee and COSMIN criteria showed that the Foot Health Status Questionnaire (FHSQ) presented the greatest number of positive values. Conclusions: The FHSQ is the highest-quality PROM currently available for the foot and ankle, for patients with DM.
Cadherin 11 Inhibition Downregulates β-catenin, Deactivates the Canonical WNT Signalling Pathway and Suppresses the Cancer Stem Cell-Like Phenotype of Triple Negative Breast Cancer
Authors: Satriyo Pamungkas Bagus , Bamodu Oluwaseun Adebayo , Chen Jia-Hong , Aryandono Teguh , Haryana Sofia Mubarika , Yeh Chi-Tai , Chao Tsu-Yi
Published: January 2019

Background: Cancer stem cells (CSCs) promote tumor progression and distant metastasis in breast cancer. Cadherin 11 (CDH11) is overexpressed in invasive breast cancer cells and implicated in distant bone metastases in several cancers. The WNT signalling pathway regulates CSC activity. Growing evidence suggest that cadherins play critical roles in WNT signalling pathway. However, CDH11 role in canonical WNT signalling and CSCs in breast cancer is poorly understood. Methods: We investigated the functional association between CDH11 and WNT signalling pathway in triple negative breast cancer (TNBC), by analyzing their expression profile in the TCGA Breast Cancer (BRCA) cohort and immunohistochemical (IHC) staining of TNBC samples. Results: We observed a significant correlation between high CDH11 expression and poor prognosis in the basal and TNBC subtypes. Also, CDH11 expression positively correlated with β-catenin, wingless type MMTV integration site (WNT)2, and transcription factor (TCF)12 expression. IHC results showed CDH11 and β-catenin expression significantly correlated in TNBC patients (p < 0.05). We also showed that siRNA-mediated loss-of-CDH11 (siCDH11) function decreases β-catenin, Met, c-Myc, and matrix metalloproteinase (MMP)7 expression level in MDA-MB-231 and Hs578t. Interestingly, immunofluorescence staining showed that siCDH11 reduced β-catenin nuclear localization and attenuated TNBC cell migration, invasion and tumorsphere-formation. Of translational relevance, siCDH11 exhibited significant anticancer efficacy in murine tumor xenograft models, as demonstrated by reduced tumor-size, inhibited tumor growth and longer survival time. Conclusions: Our findings indicate that by modulating β-catenin, CDH11 regulates the canonical WNT signalling pathway. CDH11 inhibition suppresses the CSC-like phenotypes and tumor growth of TNBC cells and represents a novel therapeutic approach in TNBC treatment.
Manufacturing and Performance Evaluation of Carbon Fiber–Reinforced Honeycombs
Authors: Rao Sanjeev , Thomas Jimmy , Aziz Alia , Cantwell Wesley
Published: January 2019

In this work, the manufacturing characteristics and a performance evaluation of carbon fiber–reinforced epoxy honeycombs are reported. The vacuum-assisted resin transfer molding process, using a central injection point, is used to infuse a unidirectional dry slit tape with the epoxy resin system Prime 20 LV in a wax mold. The compression behavior of the manufactured honeycomb structure was evaluated by subjecting samples to quasi-static compression loading. Failure criteria for the reinforced honeycombs were developed and failure maps were constructed. These maps can be used to evaluate the reliability of the core for a prescribed loading condition. Improvements in the load-carrying capacity for the reinforced samples, as compared with unreinforced specimens, are discussed and the theoretical predictions are compared with the experimental data. The compression test results highlight a load-carrying capacity up to 26 kN (~143 MPa) for a single hexagonal cell (unit cell) and 160 kN (~170 MPa) for cores consisting of 2.5 × 3.5 cells. The failure map indicates buckling to be the predominant mode of failure at low relative densities, shifting to cell wall fracture at relative densities closer to a value of 10−1. The resulting energy absorption diagram shows a monotonic increase in energy absorption with the increasing t/l ratio of the honeycomb core cell walls.
Biomaterial Enhanced Regeneration Design Research for Skin and Load Bearing Applications
Authors: Feldman Dale S.
Published: January 2019

Biomaterial enhanced regeneration (BER) falls mostly under the broad heading of Tissue Engineering: the use of materials (synthetic and natural) usually in conjunction with cells (both native and genetically modified as well as stem cells) and/or biological response modifiers (growth factors and cytokines as well as other stimuli, which alter cellular activity). Although the emphasis is on the biomaterial as a scaffold it is also the use of additive bioactivity to enhance the healing and regenerative properties of the scaffold. Enhancing regeneration is both moving more toward regeneration but also speeding up the process. The review covers principles of design for BER as well as strategies to select the best designs. This is first general design principles, followed by types of design options, and then specific strategies for applications in skin and load bearing applications. The last section, surveys current clinical practice (for skin and load bearing applications) including limitations of these approaches. This is followed by future directions with an attempt to prioritize strategies. Although the review is geared toward design optimization, prioritization also includes the commercializability of the devices. This means a device must meet both the clinical performance design constraints as well as the commercializability design constraints.
Organized Sports and Physical Activities as Sole Influencers of Fitness: The Homeschool Population
Authors: Kabiri Laura S. , Rodriguez Augusto X. , Perkins-Ball Amanda M. , Diep Cassandra S.
Published: January 2019

Homeschool children may rely solely on organized sports and physical activities to achieve recommended levels of physical activity and fitness. The purpose of this study was to investigate differences in fitness levels between homeschool children who did, and did not, participate in organized sports or physical activities, and then examine relationships between hours per week in sports or physical activities and cardiorespiratory fitness as measured by portions of the FitnessGram® test battery. Organized sports/physical activity participation information was gathered on 100 children ages 10–17 years who completed tests of upper, abdominal, and cardiorespiratory fitness. The current investigation revealed that participation alone was not associated with higher levels of physical fitness as assessed by the 90° push-up test or curl-up test nor was time in participation related to cardiorespiratory fitness as assessed by the Progressive Aerobic Capacity Endurance Run (PACER). These activities alone may be insufficient for meeting physical activity recommendations and improving physical fitness. Therefore, children and adolescents educated at home may need additional opportunities to participate in unstructured daily physical activity.
The Role of Latent Heat Flux in Tropical Cyclogenesis over the Western North Pacific: Comparison of Developing versus Non-Developing Disturbances
Authors: Gao Si , Jia Shengbin , Wan Yanyu , Li Tim , Zhai Shunan , Shen Xinyong
Published: January 2019

The possible role of air–sea latent heat flux (LHF) in tropical cyclone (TC) genesis over the western North Pacific (WNP) is investigated using state-of-the-art satellite and analysis datasets. The authors conducted composite analyses of several meteorological variables after identifying developing and non-developing tropical disturbances from June to October of the period 2000 to 2009. Compared to the non-developing disturbances, increased LHF underlying the developing disturbances enhances boundary–layer specific humidity. The secondary circulation then transports more boundary–layer moisture inward and upward and, thus, induces a stronger moist core in the middle troposphere. Accordingly, the air in the core region ascends following a warmer moist adiabat than that in the environment and results in a stronger upper-level warm core, which is associated with a stronger near-surface tangential wind based on the thermal wind balance. This enlarges the magnitude and negative radial gradient of LHF and, thereby, further increases boundary–layer specific humidity. A tropical depression forms when the near-surface tangential wind increases to a certain extent as a result of the continuing positive feedback between near-surface wind and LHF. The results suggest an important role of wind-driven LHF in TC genesis over the WNP.
Deforestation and Forest Degradation as an Environmental Behavior: Unpacking Realities Shaping Community Actions
Authors: Duguma Lalisa A. , Atela Joanes , Minang Peter A. , Ayana Alemayehu N. , Gizachew Belachew , Nzyoka Judith M. , Bernard Florence
Published: January 2019

Deforestation and forest degradation (D&D) in the tropics have continued unabated and are posing serious threats to forests and the livelihoods of those who depend on forests and forest resources. Smallholder farmers are often implicated in scientific literature and policy documents as important agents of D&D. However, there is scanty information on why smallholders exploit forests and what the key drivers are. We employed behavioral sciences approaches that capture contextual factors, attitudinal factors, and routine practices that shape decisions by smallholder farmers. Data was collected using household surveys and focus group discussions in two case study forests—Menagesha Suba Forest in Ethiopia and Maasai Mau Forest in Kenya. Our findings indicate that factors that forced farmers to engage in D&D were largely contextual, i.e., sociodemographic, production factors constraint, as well as policies and governance issues with some influences of routine practices such as wood extraction for fuelwood and construction. Those factors can be broadly aggregated as necessity-driven, market-driven, and governance-driven. In the forests studied, D&D are largely due to necessity needs and governance challenges. Though most factors are intrinsic to smallholders’ context, the extent and impact on D&D were largely aggravated by factors outside the forest landscape. Therefore, policy efforts to reduce D&D should carefully scrutinize the context, the factors, and the associated enablers to reduce forest losses under varying socioeconomic, biophysical, and resource governance conditions.
Synthetic Mutualism and the Intervention Dilemma
Authors: Denton Jai A. , Gokhale Chaitanya S.
Published: January 2019

Ecosystems are complex networks of interacting individuals co-evolving with their environment. As such, changes to an interaction can influence the whole ecosystem. However, to predict the outcome of these changes, considerable understanding of processes driving the system is required. Synthetic biology provides powerful tools to aid this understanding, but these developments also allow us to change specific interactions. Of particular interest is the ecological importance of mutualism, a subset of cooperative interactions. Mutualism occurs when individuals of different species provide a reciprocal fitness benefit. We review available experimental techniques of synthetic biology focused on engineered synthetic mutualistic systems. Components of these systems have defined interactions that can be altered to model naturally occurring relationships. Integrations between experimental systems and theoretical models, each informing the use or development of the other, allow predictions to be made about the nature of complex relationships. The predictions range from stability of microbial communities in extreme environments to the collapse of ecosystems due to dangerous levels of human intervention. With such caveats, we evaluate the promise of synthetic biology from the perspective of ethics and laws regarding biological alterations, whether on Earth or beyond. Just because we are able to change something, should we?
Modeling Sliding Friction of a Multiscale Wavy Surface over a Viscoelastic Foundation Taking into Account Adhesion
Authors: Makhovskaya Yulia
Published: January 2019

A model for calculating the hysteretic friction force for a multilevel wavy surface sliding in dry conditions over the surface of a viscoelastic foundation is suggested, taking into account adhesion force acting in the direction normal to the contact surface. At each scale level, the contact problem for a 3D periodic wavy indenter is solved by using the strip method to reduce the problem to 2D formulation in a strip. Different regimes of contact and adhesion interaction are possible in each strip, including partial and saturated contact. The friction force is calculated as a sum of two terms. The first term is due to hysteretic losses occurring when asperities of this scale level cyclically deform the viscoelastic foundation during sliding. The second term is the law of friction determined from the solution of the contact problem at the inferior scale level. For the case of a two-level wavy surface, the contribution of both levels into the total friction force is calculated and analyzed depending on the sliding velocity and specific energy of adhesion of the contacting surfaces.
Insights on the Use of Carbon Additives as Promoters of the Visible-Light Photocatalytic Activity of Bi2WO6
Authors: Gomis-Berenguer Alicia , Eliani Irma , F. Lourenço Vânia , J. Carmona Rocio , F. Velasco Leticia , O. Ania Conchi
Published: January 2019

We have explored the impact of the incorporation of various amounts of carbons from varied physicochemical features as additives to Bi2WO6 for the photocatalytic degradation of a dye using simulated solar light. Data has revealed that the composition and acidic character of the carbon additive are important parameters in the performance of the Bi2WO6/carbon catalysts. The presence of a carbon additive improved the conversion of the dye, evidencing the occurrence of charge transfer reactions that involve radical mediated reactions. The catalysts prepared with 2 and 5 wt.% of carbon additive outperformed the bare semiconductor, despite the shielding effect of the carbon matrix. The acidic nature of the Bi2WO6/carbon catalysts governs the degradation pathway (due to the preferential adsorption of the dye), that proceeds via the deethylation of the auxochrome groups of the dye at short irradiation times, followed by the cleavage of the chromophore at long irradiation times. Regarding the characteristics of the carbons, the photocatalytic degradation rate is accelerated by carbons of acidic character and high oxygen content, whereas the porosity seems to play a minor role. The presence of the carbon additives also affects the toxicity of the treated solutions, rendering lower values after shorter irradiation periods.
Surface Characteristics and Hydrophobicity of Ni-Ti Alloy through Magnetic Mixed Electrical Discharge Machining
Authors: Feng C.C. , Li L. , Zhang C.S. , Zheng G.M. , Bai X. , Niu Z.W.
Published: January 2019

Nickel–titanium (Ni-Ti) alloy has been selected as stent material given its good biocompatibility. In this study, experimental research on this material was conducted using magnetic field-assisted electrical discharge machining (EDM). The surface topography of the machined workpiece was analyzed with a scanning electron microscope (SEM). Hydrophobicity was measured by using an optical contact angle measuring instrument. The roughness values of different positions on the surface were measured using a TR200 roughness instrument. Results showed that the composite structure of solidification bulge–crater–pore–particle can be prepared on the surface of the Ni-Ti alloy through magnetic mixed EDM using suitable processing parameters. Moreover, the contact angle of the surface reaches 138.2°.
Validation of Selected Non-Destructive Methods for Determining the Compressive Strength of Masonry Units Made of Autoclaved Aerated Concrete
Authors: Jasiński Radosław , Drobiec Łukasz , Mazur Wojciech
Published: January 2019

Minor-destructive (MDT) and non-destructive (NDT) techniques are not commonly used for masonry as they are complex and difficult to perform. This paper describes validation of the following methods: semi-non-destructive, non-destructive, and ultrasonic technique for autoclaved aerated concrete (AAC). The subject of this study covers the compressive strength of AAC test elements with declared various density classes of: 400, 500, 600, and 700 (kg/m3), at various moisture levels. Empirical data including the shape and size of specimens, were established from tests on 494 cylindrical and cuboid specimens, and standard cube specimens 100 mm × 100 mm × 100 mm using the general relationship for ordinary concrete (Neville’s curve). The effect of moisture on AAC was taken into account while determining the strength fBw for 127 standard specimens tested at different levels of water content (w = 100%, 67%, 33%, 23%, and 10%). Defined empirical relations were suitable to correct the compressive strength of dry specimens. For 91 specimens 100 mm × 100 mm × 100 mm, the P-wave velocity cp was tested with the transmission method using the ultrasonic pulse velocity method with exponential transducers. The curve (fBw–cp) for determining the compressive strength of AAC elements with any moisture level (fBw) was established. The developed methods turned out to be statistically significant and can be successfully applied during in-situ tests. Semi-non-destructive testing can be used independently, whereas the non-destructive technique can be only applied when the developed curve fbw–cp is scaled.
Enhanced Wear Performance of Cu-Carbon Nanotubes Composite Coatings Prepared by Jet Electrodeposition
Authors: Ning Dongdong , Zhang Ao , Wu Hui
Published: January 2019

Cu-carbon nanotubes (CNTs) composite coatings with high CNT content and uniformly distributed CNTs were successfully prepared via jet electrodeposition. Pristine CNTs, without any treatment like acid functionalization, were used. Anionic surfactant sodium dodecyl sulfate (SDS) was used to increase the wettability of the CNTs and improve the content of incorporated CNTs. With an appropriate SDS concentration (300 mg/L) in the electrolyte, the incorporated CNT content is as high as 2.84 wt %, much higher than the values reported using conventional electrodeposition (0.42–1.05 wt %). The high-content CNTs were uniformly distributed in the composite coating. The surface morphology of this composite coating (2.84 wt % CNTs) was flat due to the uniform electric field in jet electrodeposition. In the wear test a with load of 1 N and sliding speed of 0.02 m/s, the wear rate of this composite coating was 1.3 × 10−2 mg/Nm, 85.4% lower than that of pure Cu. The enhanced wear performance of Cu-CNTs composite coatings can be attributed to high CNT content and flat surface morphology.
The Fabrication of Fragrance Microcapsules and Their Sustained and Broken Release Behavior
Authors: Zhao Hongbin , Fei Xuening , Cao Lingyun , Zhang Baolian , Liu Xin
Published: January 2019

Their controlled release property is the most important feature of functional microcapsules and carriers. In this work, melamine resin shell fragrance microcapsules were fabricated in a non-ionic system, and their chemical structure, particle size, and morphology were analyzed. The sustained release property of the prepared microcapsules over 2400 h was studied with a weighing calculation method, and based on the fitting results, the release rate trend was consistent with the Peppas model (y = 100 − 2.30t0.3213). Furthermore, the sustained and broken release behavior of the microcapsules in impregnated fabric samples were investigated for the first time by our proposed Solid Phase Microextraction-Gas Chromatography-Mass Spectrometer (SPME-GC-MS) method. The qualitative and quantitative analysis results showed that the middle and base note compositions were outstanding in the sustained release state, and the top note showed more advantages in the broken release state. In addition, it was found that the characteristic peak species and intensities of the sample finished with the microcapsules were more similar to pure essence oil than the sample finished by traditional methods, suggesting that the prepared microcapsules showed an excellent odor recovery and strength.
Characterization of Asphalt Mixture Moduli under Different Stress States
Authors: Fan Xiyan , Lv Songtao , Zhang Naitian , Xia Chengdong , Li Yipeng
Published: January 2019

Modulus testing methods under various test conditions have a large influence on modulus test results, which hinders the accurate evaluation of the stiffness of asphalt mixtures. In order to decrease the uncertainty in the stiffness characteristics of asphalt mixtures under various stress states, the traditional unconfined compression test, direct tensile test, and the synchronous test method, based on the indirect tension and four-point bending tests, were carried out for different loading frequencies. Results showed that modulus test results were highly sensitive to the shape, size, and stress state of the specimen. Additionally, existing modulus characteristics did not reduce these differences. There is a certain correlation between the elastic modulus ratio and the frequency ratio for asphalt under multiple stress states. The modulus, under multiple stress states, was processed using min–max normalization. Then, the standardization model for tensile and compressive characteristics of asphalt under diverse stress states was established based on the sample preparation, modulus ratio variations, and loading frequency ratio. A method for deriving other moduli from one modulus was realized. It is difficult to evaluate the stiffness performance in diverse stress states for asphalt by only using conventional compressive and tensile tests. However, taking into account the effects of stress states and loading frequencies, standardized models can be used to reduce or even eliminate these effects. The model realizes the unification of different modulus test results, and provides a theoretical, methodological, and technical basis for objectively evaluating moduli.
Laser Microdrilling of Slate Tiles
Authors: Penide Joaquín , Riveiro Antonio , Soto Ramón , Boutinguiza Mohamed , Arias-Gonzalez Felipe , del Val Jesús , Comesaña Rafael , Lusquiños Fernando , Quintero Félix , Pou Juan
Published: January 2019

Slate is a natural rock usually used in roofs, façades, and for tiling. In spite of this broad use, the production process of slate tiles requires substantial improvements. An important quantity of slate from the quarry is wasted during the manufacturing of the final product. Furthermore, processes are not automatized and the production lead times can be considerably shortened. Therefore, new processing methods to increase productivity, reduce costs and to provide added value to the final slate product are required. Drilling is an important part of these manufacturing processes. Conventional drilling processes usually cause the breaking of the slate tiles; then, even a higher quantity of material is wasted. To overcome these problems, lasers emerge as a feasible tool to produce holes in this material, since mechanical stresses are not induced on the workpiece. In this work, we have studied the CO2 laser microdrilling of slate tiles. We used a Design of Experiments (DOE) methodology to determine the influence of the laser processing parameters on the hole quality. This work demonstrates the capability of a CO2 laser to produce holes in slate with less than 100 microns in diameter, avoiding any fracture, and with a processing time of less than 50 ms per hole. Finally, this process demonstrates the viability of the production of high-density micron-sized holes in a slate tile for water draining purposes.
Investigation of Ferroelectric Grain Sizes and Orientations in Pt/CaxSr1–xBi2Ta2O9/Hf–Al–O/Si High Performance Ferroelectric-Gate Field-Effect-Transistors
Authors: Zhang Wei , Takahashi Mitsue , Sakai Shigeki
Published: January 2019

Electron backscatter diffraction (EBSD) was applied to investigate the grain size and orientation of polycrystalline CaxSr1–xBi2Ta2O9 (CxS1–xBT) films in ferroelectric-gate field-effect transistors (FeFETs). The CxS1–xBT FeFETs with x = 0, 0.1, 0.2, 0.5, and 1 were characterized by the EBSD inverse pole figure map. The maps of x = 0, 0.1, and 0.2 showed more uniform and smaller grains with more inclusion of the a-axis component along the film normal than the maps of x = 0.5 and 1. Since spontaneous polarization of CxS1–xBT is expected to exist along the a-axis, inclusion of the film normal a-axis component is necessary to obtain polarization versus electric field (P–E) hysteresis curves of the CxS1–xBT when the E is applied across the film. Since memory windows of FeFETs originate from P–E hysteresis curves, the EBSD results were consistent with the electrical performance of the FeFETs, where the FeFETs with x = 0, 0.1, and 0.2 had wider memory windows than those with x = 0.5 and 1. The influence of annealing temperature for C0.1S0.9BT poly-crystallization was also investigated using the EBSD method.
Evaluation of the Properties of Asphalt Mixes Modified with Diatomite and Lignin Fiber: A Review
Authors: Yue Yanchao , Abdelsalam Moustafa , Luo Dong , Khater Ahmed , Musanyufu Josephine , Chen Tangbing
Published: January 2019

Due to rapid growth of traffic density, the phenomenon of overloading on high-grade highways causes various modes of distresses to the pavement such as rutting, thermal cracking, and water damage. Modification of asphalt mixes is the most common solution to improve the performance of asphalt pavement to mitigate its damages. This paper provides a review on the influence of diatomite or lignin fiber as a modifier in asphalt mixes. In order to assess the effectiveness of selected additives on asphalt mix performance, several tests, such as wheel tracking, indirect tensile, three points bending, freeze thaw splitting, and marshall immersion, were reviewed. The review indicated that the addition of diatomite increases the high temperature rutting resistance of asphalt mixes, but some researchers observed that it has a little improvement on the low temperature performance of asphalt mixes and the optimum amount of diatomite at 12–14% of asphalt binder can be added into the mix. In contrast, lignin fiber has a significant effect on the low temperature cracking resistance of asphalt mixes; however, its influence on the high temperature rutting resistance of asphalt mix is limited, and the optimum amount of lignin fiber is 0.2–0.4% per asphalt mix composition. The review also indicated that the single additives haven’t the ability to enhance the overall performance of asphalt mix. Consequently, the utilization of double additives can improve the overall performance of asphalt mixes at the same time, but it is still in an early stage in the application of highway engineering due to all previous researches concentrated on the single modification. Moreover, this review suggests that the future use of diatomite and lignin fiber compound modified asphalt mix can improve the overall mix performance.