bluuebunny/crossref_metadata_2025 huggingface dataset:
Drosophila Gut—A Nexus Between Dietary Restriction and Lifespan
Authors: Lian Ting , Wu Qi , Hodge Brian A. , Wilson Kenneth A. , Yu Guixiang , Yang Mingyao
Published: November 2018

Aging is often defined as the accumulation of damage at the molecular and cellular levels which, over time, results in marked physiological impairments throughout the organism. Dietary restriction (DR) has been recognized as one of the strongest lifespan extending therapies observed in a wide array of organisms. Recent studies aimed at elucidating how DR promotes healthy aging have demonstrated a vital role of the digestive tract in mediating the beneficial effects of DR. Here, we review how dietary restriction influences gut metabolic homeostasis and immune function. Our discussion is focused on studies of the Drosophila digestive tract, where we describe in detail the potential mechanisms in which DR enhances maintenance of the intestinal epithelial barrier, up-regulates lipid metabolic processes, and improves the ability of the gut to deal with damage or stress. We also examine evidence of a tissue-tissue crosstalk between gut and neighboring organs including brain and fat body. Taken together, we argue that the Drosophila gut plays a critical role in DR-mediated lifespan extension.
Ontology-Based Representation for Accessible OpenCourseWare Systems
Authors: Elias Mirette , Lohmann Steffen , Auer Sören
Published: November 2018

OpenCourseWare (OCW) systems have been established to provide open educational resources that are accessible by anyone, including learners with special accessibility needs and preferences. We need to find a formal and interoperable way to describe these preferences in order to use them in OCW systems and retrieve relevant educational resources. This formal representation should use standard accessibility definitions of OCW that can be reused by other OCW systems to represent accessibility concepts. In this article, we present an ontology to represent the accessibility needs of learners with respect to the IMS AfA specifications. The ontology definitions together with rule-based queries are used to retrieve relevant educational resources. Related to this, we developed a user interface component that enables users to create accessibility profiles representing their individual needs and preferences based on our ontology. We evaluated the approach with five examples profiles.
Domain-Specific Aspect-Sentiment Pair Extraction Using Rules and Compound Noun Lexicon for Customer Reviews
Authors: Ahamed Kabeer Noor Rizvana , Gan Keng Hoon , Haris Erum
Published: November 2018

Online reviews are an important source of opinion to measure products’ quality. Hence, automated opinion mining is used to extract important features (aspect) and related comments (sentiment). Extraction of correct aspect-sentiment pairs is critical for overall outcome of opinion mining; however, current works still have limitations in terms of identifying special compound noun and parent-child relationship aspects in the extraction process. To address these problems, an aspect-sentiment pair extraction using the rules and compound noun lexicon (ASPERC) model is proposed. The model consists of three main phases, such as compound noun lexicon generation, aspect-sentiment pair rule generation, and aspect-sentiment pair extraction. The combined approach of rules generated from training sentences and domain specific compound noun lexicon enable extraction of more aspects by firstly identifying special compound noun and parent-child aspects, which eventually contribute to more aspect-sentiment pair extraction. The experiment is conducted with the SemEval 2014 dataset to compare proposed and baseline models. Both ASPERC and its variant, ASPER, result higher in recall (28.58% and 22.55% each) compared to baseline and satisfactorily extract more aspect sentiment pairs. Lastly, the reasonable outcome of ASPER indicates applicability of rules to various domains.
Investigation on the Overshoot of Transient Open-Circuit Voltage in Methylammonium Lead Iodide Perovskite Solar Cells
Authors: Li Chunhai , Lv Longfeng , Qin Liang , Zhu Lijie , Teng Feng , Lou Zhidong , Deng Zhenbo , Hu Yufeng , Cui Qiuhong , Hou Yanbing
Published: November 2018

Although the performance of hybrid organic-inorganic perovskite solar cells (PSCs) is encouraging, the detailed working principles and mechanisms of PSCs remain to be further studied. In this work, an overshoot phenomenon of open-circuit voltage (Voc) was observed when the illumination light pulse was switched off. The evolution of the Voc overshoot was systematically investigated along with the intensity and the width of the light pulse, the background illumination, and pretreatment by different bias. Based on the experimental results, we could conclude that the Voc overshoot originated from carrier motion against carrier collection direction, which happened at the ionic-accumulation-induced band bending areas near the interfaces between the perovskite active layer and the two carrier transport layers. The investigation on the Voc overshoot can help us to better understand ionic migration, carrier accumulation, and recombination of PSCs under open-circuit conditions.
Tribological Behavior of Copper–Graphite Composites Reinforced with Cu-Coated or Uncoated SiO2 Particles
Authors: Zou Haohao , Ran Xu , Zhu Weiwei , Wang Yong , Zhan Siqi , Hao Zhikang
Published: November 2018

Copper–graphite composites reinforced with SiO2 particles were fabricated by powder metallurgy technique. Electroless copper plating was introduced to improve the interfacial bonding between SiO2 particles and copper matrix. The microstructure, density, and hardness of the composites were characterized. The tribological properties, such as friction coefficient and wear rate of the composites, were studied using a pin-on-ring tribometer. The results show that the hard SiO2 can restrict the severe plastic deformation and adhesion contact in the process of wear. At the same time, parts of SiO2 particles can be broken into fine particles during wear process, which is helpful for decreasing adhesion wear and abrasive wear. Therefore, the addition of SiO2 leads to increasing friction stability and friction coefficient, and decreasing wear rate. In addition, the electroless copper plating improves the interfacial bonding between SiO2 and copper matrix, which prevents separation of SiO2 from copper matrix and further increase tribological properties of the composites.
The Anti-Angiogenic Activity of a Cystatin F Homologue from the Buccal Glands of Lampetra morii
Authors: Zhu Mingru , Li Bowen , Wang Jihong , Xiao Rong
Published: November 2018

Cystatins are a family of cysteine protease inhibitors which are associated with a variety of physiological and pathological processes in vivo. In the present study, the cDNA sequence of a cystatin F homologue called Lm-cystatin F was cloned from the buccal glands of Lampetra morii. Although Lm-cystatin F shares a lower homology with cystatin superfamily members, it is also composed of a signal peptide and three highly conserved motifs, including the G in the N-terminal, QXVXG, as well as the PW in the C-terminal of the sequence. After sequence optimization and recombination, the recombinant protein was expressed as a soluble protein in Escherichia coli with a molecular weight of 19.85 kDa. Through affinity chromatography and mass spectrometry analysis, the purified protein was identified as a recombinant Lm-cystatin F (rLm-cystatin F). Additionally, rLm-cystatin F could inhibit the activity of papain. Based on MTT assay, rLm-cystatin F inhibited the proliferation of human umbilical vein endothelial cells (HUVECs) dose dependently with an IC50 of 5 μM. In vitro studies show that rLm-cystatin F suppressed the adhesion, migration, invasion, and tube formation of HUVECs, suggesting that rLm-cystatin F possesses anti-angiogenic activity, which provides information on the feeding mechanisms of Lampetra morii and insights into the application of rLm-cystatin F as a potential drug in the future.
From Rapid Recommendation to Online Preference-Sensitive Decision Support: The Case of Severe Aortic Stenosis
Authors: Dowie Jack , Kaltoft Mette Kjer
Published: November 2018

The launch of ‘Rapid Recommendations’ by the Grading of Recommendations Assessment, Development and Evaluation (GRADE) group, in collaboration with Making GRADE the Irresistible Choice (MAGIC) and the British Medical Journal (BMJ), is a very interesting recent development in e-healthcare. Designed to respond quickly to developments that have created new decision situations, their first project resulted from the arrival of minimally invasive Transcatheter Aortic Valve Implantation (TAVI) as an alternative to Surgical Aortic Valve Replacement (SAVR), for patients with symptomatic severe aortic stenosis. The interactive MAGIC decision aid that accompanies a Rapid Recommendation and is the main route to its clinical implementation, represents a major advance in e-health, for a cardiovascular decision in this case. However, it needs to go further in order to facilitate fully person-centred care, where the weighted preferences of the individual person are elicited at the point of decision, and transparently integrated with the best (most personalised) estimates of option performances, to produce personalised, preference-sensitive option evaluations. This can be achieved by inputting the collated GRADE evidence on the criteria relevant in the TAVI/SAVR choice into a Multi-Criteria Decision Analysis-based decision support tool, generating a personalised, preference-sensitive opinion. A demonstration version of this add-on to the MAGIC aid, divested of recommendations, is available online as proof of method.
A MEMS Variable Optical Attenuator with Ultra-Low Wavelength-Dependent Loss and Polarization-Dependent Loss
Authors: Sun Huangqingbo , Zhou Wei , Zhang Zijing , Wan Zhujun
Published: November 2018

Applications in broadband optical fiber communication system need variable optical attenuators (VOAs) with low wavelength-dependent loss (WDL). Based on analysis on the dispersion of the optical system of a MEMS-based VOA, we provide a method to reduce the WDL significantly with minor revision on the end-face angle of the collimating lens. Two samples are assembled, and the measured WDL is <0.4 dB over the C-band (1.53–1.57 μm) at a 0–20 dB attenuation range. Meanwhile, the new structure helps to reduce the polarization-dependent loss (PDL) to <0.15 dB, which is only half that of conventional devices.
Three Inulin-Type Fructans from Codonopsis pilosula (Franch.) Nannf. Roots and Their Prebiotic Activity on Bifidobacterium longum
Authors: Li Jiankuan , Zhang Xin , Cao Lingya , Ji Jiaojiao , Gao Jianping
Published: November 2018

Radix Codonopsis, derived from the roots of Codonopsis pilosula (Franch.) Nannf., Codonopsis pilosula (Franch.) Nannf. Var. modesta (Nannf.) L.T. Shen and Codonopsis tangshen Oliv., has been used as traditional Chinese medicine for improving poor gastrointestinal function, treating gastric ulcers and chronic gastritis in China. Inulin-type fructans are carbohydrates consisting mainly of β (2→1) fructosyl-fructose links in chemical structure and exhibit a range of properties such as prebiotic activity, fat substitutes in low-calorie foods and disease-modifying effects. The prebiotic effects of inulin-type fructans are hypothesized to improve gastrointestinal function through alterations to gut microbiota composition and metabolism. In the present study, three inulin-type fructans with high degree of polymerization (DP = 16, 22, and 31) were isolated from the roots of Codonopsis pilosula (Franch.) Nannf. and their structures were confirmed by MALDI-TOF-MS, 1D- and 2D-NMR. The prebiotic activity of these fructans was evaluated by detecting growth stimulation on Bifidobacterium longum. The results demonstrated that three fructans at a concentration of 2.0 g/L exhibited significant growth stimulation on Bifidobacterium longum in a time-dependent manner (p < 0.01). The data indicated that inulin-type fructans in Radix Codonopsis could be used as potential prebiotics.
Anti-Inflammatory, Antioxidant, and Hypolipidemic Effects of Mixed Nuts in Atherogenic Diet-Fed Rats
Authors: Hong Mee Young , Groven Shauna , Marx Amanda , Rasmussen Caitlin , Beidler Joshua
Published: November 2018

Nut consumption is associated with reduced risk of cardiovascular disease (CVD). Because most studies have administered single nut varieties, it is unknown whether mixed nuts will also reduce CVD risk. The objective of this study was to compare the effects of mixed nut and pistachio consumption on lipid profiles, glucose, inflammation, oxidative stress, and antioxidant capacity in rats fed an atherogenic diet. Thirty male Sprague-Dawley rats (21 days old) were assigned into three groups (n = 10) based on initial body weight and fed either an isocaloric control diet (no nuts), 8.1% pistachio diet (single nut), or 7.5% mixed nut diet (almonds, brazil nuts, cashews, macadamia nuts, peanuts, pecans, pistachios, and walnuts) for 8 weeks. Both pistachios and mixed nuts significantly decreased triglycerides, total cholesterol, and LDL-cholesterol (p < 0.05) compared with controls. Both nut groups exhibited reductions in C-reactive protein (p = 0.045) and oxidative stress (p = 0.004). The mixed nut group had greater superoxide dismutase (p = 0.004) and catalase (p = 0.044) and lower aspartate aminotransferase (p = 0.048) activities. Gene expression for Fas, Hmgcr, and Cox2 was downregulated for both nut groups compared to controls (p < 0.05). In conclusion, mixed nuts and individual nut varieties have comparable effects on CVD risk factors in rats.
Characterization and Antiproliferative Activity of a Novel 2-Aminothiophene Derivative-β-Cyclodextrin Binary System
Authors: Ferreira Elayne Barros , Da Silva Júnior Walter Ferreira , De Oliveira Pinheiro Jonas Gabriel , Da Fonseca Aldilane Gonçalves , Moura Lemos Telma Maria Araújo , De Oliveira Rocha Hugo Alexandre , De Azevedo Eduardo Pereira , Mendonça Junior Francisco Jaime Bezerra , Neves de Lima Ádley Antonini
Published: November 2018

The novel 2-aminothiophene derivative 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile (6CN) has shown potential anti-proliferative activity in human cancer cell lines. However, the poor aqueous solubility of 6CN impairs its clinical use. This work aimed to develop binary 6CN-β-cyclodextrin (βCD) systems with the purpose of increasing 6CN solubility in water and therefore, to improve its pharmacological activity. The 6CN-βCD binary systems were prepared by physical mixing, kneading and rotary evaporation methods and further characterized by FTIR, XRD, DSC, TG and SEM. In addition, molecular modeling and phase solubility studies were performed. Finally, MTT assays were performed to investigate the cytostatic and anti-proliferative effects of 6CN-βCD binary systems. The characterization results show evident changes in the physicochemical properties of 6CN after the formation of the binary systems with βCD. In addition, 6CN was associated with βCD in aqueous solution and the solid state, which was confirmed by molecular modeling and the aforementioned characterization techniques. Phase solubility studies indicated that βCD forms stable 1:1 complexes with 6CN. The MTT assay demonstrated the cytostatic and anti-proliferative activities of 6CN-βCD binary systems and therefore, these might be considered as promising candidates for new anticancer drugs.
Monomyristin and Monopalmitin Derivatives: Synthesis and Evaluation as Potential Antibacterial and Antifungal Agents
Authors: Jumina  , Nurmala Asma , Fitria Anggit , Pranowo Deni , Sholikhah Eti Nurwening , Kurniawan Yehezkiel Steven , Kuswandi Bambang
Published: November 2018

In the present work, monoacylglycerol derivatives, i.e., 1-monomyristin, 2-monomyristin, and 2-monopalmitin were successfully prepared from commercially available myristic acid and palmitic acid. The 1-monomyristin compound was prepared through a transesterification reaction between ethyl myristate and 1,2-O-isopropylidene glycerol, which was obtained from the protection of glycerol with acetone, then followed by deprotection using Amberlyst-15. On the other hand, 2-monoacylglycerol derivatives were prepared through enzymatic hydrolysis of triglycerides in the presence of Thermomyces lanuginosa lipase enzymes. The synthesized products were analyzed using fourier transform infrared (FTIR) spectrophotometer, gas or liquid chromatography-mass spectrometer (GC-MS or LC-MS), and proton and carbon nuclear magnetic resonance (1H- and 13C-NMR) spectrometers. It was found that monomyristin showed high antibacterial and antifungal activities, while 2-monopalmitin did not show any activity at all. The 1-monomyristin compound showed higher antibacterial activity against Staphylococcus aureus and Aggregatibacter actinomycetemcomitans and also higher antifungal activity against Candida albicans compared to the positive control. Meanwhile, 2-monomyristin showed high antibacterial activity against Escherichia coli. The effect of the acyl position and carbon chains towards antibacterial and antifungal activities was discussed.
Up-Conversion Luminescence Properties of Lanthanide-Gold Hybrid Nanoparticles as Analyzed with Discrete Dipole Approximation
Authors: Lv Ruichan , Feng Miao , Parak Wolfgang J.
Published: November 2018

Up-conversion nanoparticles (UCNP) under near-infrared (NIR) light irradiation have been well investigated in the field of bio-imaging. However, the low up-conversion luminescence (UCL) intensity limits applications. Plasmonic modulation has been proposed as an effective tool to adjust the luminescence intensity and lifetime. In this study discrete dipole approximation (DDA) was explored concerning guiding the design of UCNP@mSiO2-Au structures with enhanced UCL intensity. The extinction effects of gold shells could be changed by adjusting the distance between the UCNPs and the Au NPs by synthesized tunable mesoporous silica (mSiO2) spacers. Enhanced UCL was obtained under 808 nm irradiation. The original theoretical predictions could not be demonstrated to full extend by experimental data, indicating that better models for simulation need to take into account in homogeneities in particle morphologies. Yet, one very certain conclusion resulting from the DDA calculations and experiments is that the absorbance can blue-shift with more Au NPs added and the absorbance can-red shift for samples with enhanced silica sizes in the UCNP@mSiO2-Au structures. Furthermore, when the DDA model is more consistent with the practical structure (dispersed Au NPs instead of Au shell), the theoretical absorbance occurs almost the same as the practical absorbance. All in all, the DDA could fit the extinction effect of Au perfectly and be suitable for guiding how to design the UCNP and Au.
Daily Yogurt Consumption Improves Glucose Metabolism and Insulin Sensitivity in Young Nondiabetic Japanese Subjects with Type-2 Diabetes Risk Alleles
Authors: Watanabe Daiki , Kuranuki Sachi , Sunto Akiko , Matsumoto Naoki , Nakamura Teiji
Published: November 2018

This study investigated whether the association between postprandial plasma glucose (PPG) is affected by five type 2 diabetes mellitus (T2DM) susceptibility genes, and whether four weeks of yogurt consumption would affect these responses. We performed a single-arm intervention study in young nondiabetic Japanese participants, who consumed 150 g yogurt daily for four weeks, after which a rice test meal containing 50 g carbohydrate was administered. PPG and postprandial serum insulin (PSI) were measured between 0 and 120 mins at baseline and after the intervention. Genetic risk was evaluated by weighted genetic risk score (GRS) according to published methodology, and participants were assigned to one of two groups (n = 17: L-GRS group and n = 15: H-GRS group) according to the median of weighted GRS. At baseline, the H-GRS group had higher glucose area under the curve0–120 min after intake of the test meal than the L-GRS group (2175 ± 248 mg/dL.min vs. 1348 ± 199 mg/dL.min, p < 0.001), but there were no significant differences after the yogurt intervention. However, there was an improvement in PSI in the H-GRS group compared with baseline. These results suggest that habitual yogurt consumption may improve glucose and insulin responses in nondiabetic subjects who have genetically higher PPG.
The Role of Disaccharidase Deficiencies in Functional Abdominal Pain Disorders—A Narrative Review
Authors: Puertolas Mora V. , Fifi Amanda C.
Published: November 2018

Disaccharidase deficiencies are reportedly underdiagnosed in pediatric populations. Though typically thought to cause diarrheal disease, they can also be a cause of abdominal pain and dyspepsia, and patients diagnosed with these functional disorders may actually have associated enzyme deficiencies. While the effects of lactose deficiency have been widely studied, sucrase, maltase, and isomaltase are less frequently considered when approaching a patient with an apparent functional abdominal pain disorder. This review seeks to provide an up-to-date narrative on the current scientific literature on the possible role of sucrase, maltase, and isomaltase deficiency in pediatric functional gastrointestinal disorders.
The Day of Prayer and Its Potential for Engendering Public Ecclesiology Ecumenism in Zambia
Authors: Kaunda Chammah J.
Published: November 2018

This article argues that while the National Day of Prayer in Zambia has its inception in political context, it has obligated the institutional churches to break out of their religiously fixed spaces, forcing them to suspend their official doctrinal positions for that specific day, and embrace each other in enacting what could be classified as “public ecclesiology ecumenism”. The article defines public ecclesiology ecumenism as the manifestation of institutionally-defined churches in public spaces to celebrate a common liturgical life in Christ through prayer, songs, preaching, and promotion of unified prophetic witness in the public. However, being a political initiative makes the Day of Prayer a potentially dangerous neo-colonial space for advancing a dominant political ideology which perpetuates corruption and exploitation of the masses. Thus, one of the core tasks of the churches is to liberate, reclaim, and reconstitute the Day of Prayer into a prophetic site of struggle against political corruption and poor governance by seeking to produce alternative public and political cultures.
Ground-Level PM2.5 Concentration Estimation from Satellite Data in the Beijing Area Using a Specific Particle Swarm Extinction Mass Conversion Algorithm
Authors: Li Ying , Xue Yong , Guang Jie , She Lu , Fan Cheng , Chen Guili
Published: November 2018

Particulate matter (PM) has a substantial influence on the environment, climate change and public health. Due to the limited spatial coverage of a ground-level PM2.5 monitoring system, the ground-based PM2.5 concentration measurement is insufficient in many circumstances. In this paper, a Specific Particle Swarm Extinction Mass Conversion Algorithm (SPSEMCA) using remotely sensed data is introduced. Ground-level observed PM2.5, planetary boundary layer height (PBLH) and relative humidity (RH) reanalyzed by the European Centre for Medium-Range Weather Forecasts (ECMWF) and aerosol optical depth (AOD), fine-mode fraction (FMF), particle size distribution, and refractive indices from AERONET (Aerosol Robotic Network) of the Beijing area in 2015 were used to establish this algorithm, and the same datasets for 2016 were used to test the performance of the SPSEMCA. The SPSEMCA involves four steps to obtain PM2.5 values from AOD datasets, and every step has certain advantages: (I) In the particle correction, we use η2.5 (the extinction fraction caused by particles with a diameter less than 2.5 μm) to make an accurate assimilation of AOD2.5, which is contributed to by the specific particle swarm PM2.5. (II) In the vertical correction, we compare the performance of PBLHc retrieved by satellite Lidar CALIPSO data and PBLHe reanalysis by ECMWF. Then, PBLHc is used to make a systematic correction for PBLHe. (III) For extinction to volume conversion, the relative humidity and the FMF are used together to assimilate the AVEC (averaged volume extinction coefficient, μm2/μm3). (IV) PM2.5 measured by ground-based air quality stations are used as the dry mass concentration when calculating the AMV (averaged mass volume, cm3/g) in humidity correction, that will avoid the uncertainties derived from the estimation of the particulate matter density ρ. (V) Multi-Angle Implementation of Atmospheric Correction (MAIAC) 1 km × 1 km AOD was used to retrieve high resolution PM2.5, and a LookUP Table-based Spectral Deconvolution Algorithm (LUT-SDA) FMF was used to avoid the large uncertainties caused by the MODIS FMF product. The validation of PM2.5 from the SPSEMCA algorithm to the AERONET observation data and MODIS monitoring data achieved acceptable results, R = 0.70, RMSE (root mean square error) = 58.75 μg/m3 for AERONET data, R = 0.75, RMSE = 43.38 μg/m3 for MODIS data, respectively. Furthermore, the trend of the temporal and spatial distribution of Beijing was revealed.
Multi-Temporal Vineyard Monitoring through UAV-Based RGB Imagery
Authors: Pádua Luís , Marques Pedro , Hruška Jonáš , Adão Telmo , Peres Emanuel , Morais Raul , Sousa Joaquim J.
Published: November 2018

This study aimed to characterize vineyard vegetation thorough multi-temporal monitoring using a commercial low-cost rotary-wing unmanned aerial vehicle (UAV) equipped with a consumer-grade red/green/blue (RGB) sensor. Ground-truth data and UAV-based imagery were acquired on nine distinct dates, covering the most significant vegetative growing cycle until harvesting season, over two selected vineyard plots. The acquired UAV-based imagery underwent photogrammetric processing resulting, per flight, in an orthophoto mosaic, used for vegetation estimation. Digital elevation models were used to compute crop surface models. By filtering vegetation within a given height-range, it was possible to separate grapevine vegetation from other vegetation present in a specific vineyard plot, enabling the estimation of grapevine area and volume. The results showed high accuracy in grapevine detection (94.40%) and low error in grapevine volume estimation (root mean square error of 0.13 m and correlation coefficient of 0.78 for height estimation). The accuracy assessment showed that the proposed method based on UAV-based RGB imagery is effective and has potential to become an operational technique. The proposed method also allows the estimation of grapevine areas that can potentially benefit from canopy management operations.
Developing Land Use Land Cover Maps for the Lower Mekong Basin to Aid Hydrologic Modeling and Basin Planning
Authors: Spruce Joseph , Bolten John , Srinivasan Raghavan , Lakshmi Venkat
Published: November 2018

This paper discusses research methodology to develop Land Use Land Cover (LULC) maps for the Lower Mekong Basin (LMB) for basin planning, using both MODIS and Landsat satellite data. The 2010 MODIS MOD09 and MYD09 8-day reflectance data was processed into monthly NDVI maps with the Time Series Product Tool software package and then used to classify regionally common forest and agricultural LULC types. Dry season circa 2010 Landsat top of atmosphere reflectance mosaics were classified to map locally common LULC types. Unsupervised ISODATA clustering was used to derive most LULC classifications. MODIS and Landsat classifications were combined with GIS methods to derive final 250-m LULC maps for Sub-basins (SBs) 1–8 of the LMB. The SB 7 LULC map with 14 classes was assessed for accuracy. This assessment compared random locations for sampled types on the SB 7 LULC map to geospatial reference data such as Landsat RGBs, MODIS NDVI phenologic profiles, high resolution satellite data, and Mekong River Commission data (e.g., crop calendars). The SB 7 LULC map showed an overall agreement to reference data of ~81%. By grouping three deciduous forest classes into one, the overall agreement improved to ~87%. The project enabled updated regional LULC maps that included more detailed agriculture LULC types. LULC maps were supplied to project partners to improve use of Soil and Water Assessment Tool for modeling hydrology and water use, plus enhance LMB water and disaster management in a region vulnerable to flooding, droughts, and anthropogenic change as part of basin planning and assessment.
Reconstruction of Cylindrical Surfaces Using Digital Image Correlation
Authors: Berveglieri Adilson , Tommaselli Antonio M. G.
Published: November 2018

A technique for the reconstruction of cylindrical surfaces using optical images with an extension of least squares matching is presented. This technique is based on stereo-image acquisition of a cylindrical object, and it involves displacing the camera following the object length. The basic concept behind this technique is that variations in the camera viewpoint over a cylindrical object produce perspective effects similar to a conic section in an image sequence. Such parallax changes are continuous and can be modelled by a second-order function, which is combined with an adaptive least squares matching (ALSM) for the 3D object reconstruction. Using this concept, a photogrammetric intersection with only two image patches can be used to model a cylindrical object with high accuracy. Experiments were conducted with a cylinder on a panel with coded targets to assess the 3D reconstruction accuracy. The accuracy assessment was based on a comparison between the estimated diameter and the diameter directly measured over the cylinder. The difference between the diameters indicated an accuracy of 1/10 mm, and the cylindrical surface was entirely reconstructed.
Field Evaluation of a Portable Whispering Gallery Mode Accelerometer
Authors: Li Ying Lia , Barker P. F.
Published: November 2018

An accelerometer utilising the optomechanical coupling between an optical whispering gallery mode (WGM) resonance and the motion of the WGM cavity itself was prototyped and field-tested on a vehicle. We describe the assembly of this portable, battery operated sensor and the field-programmable gate array automation. Pre-trial testing using an electrodynamic shaker demonstrated linear scale-factors with <0.3% standard deviation ( ± 6 g range where g = 9.81 ms − 2 ), and a strong normalised cross-correlation coefficient (NCCC) of r ICP / WGM = 0.997 when compared with an integrated circuit piezoelectric (ICP) accelerometer. A noise density of 40 μ g Hz − 1 / 2 was obtained for frequencies of 2–7 kHz, increasing to 130 μ g Hz − 1 / 2 at 200 Hz, and 250 μ g Hz − 1 / 2 at 100 Hz. A reduction in the cross-correlation was found during the trial, r ICP / WGM = 0.36, which we attribute to thermal fluctuations, mounting differences, and the noisy vehicle environment. The deployment of this hand-fabricated sensor, shown to operate and survive during ±60 g shocks, demonstrates important steps towards the development of a chip-scale device.
Evaluation of a Low Cost Hand Held Unit with GNSS Raw Data Capability and Comparison with an Android Smartphone
Authors: Lachapelle Gérard , Gratton Paul , Horrelt Jamie , Lemieux Erica , Broumandan Ali
Published: November 2018

A newly available portable unit with GNSS raw data recording capability is assessed to determine static and kinematic position accuracy in various environments. This unit is the GPSMap 66, introduced by Garmin in early September. It is all-weather and robust for field use, and comes with a helix antenna. The high sensitivity chipset is capable of acquiring and tracking signals in highly attenuated environments. It can track single frequency GPS, GPS + GLONASS or GPS + Galileo and record code, Doppler and carrier phase data every second in the RINEX format. The evaluation presented herein focusses on GPS and Galileo. Static and kinematic test results obtained under a wide range of realistic field conditions are reported. Differential GNSS methods and Precise Point Positioning (PPP) are used to assess absolute position accuracy in ITRF coordinates, which is sufficiently close to the GPS and Galileo reference frame for the current purpose. Under low multipath conditions, measurements are found to be sufficiently accurate to provide single epoch, bias free position accuracy of a few metres. Accuracy is a function of signal attenuation and multipath conditions. The use of an external geodetic antenna significantly reduces measurement noise and multipath in high multipath environments. Carrier phase measurements, available more or less continuously under open sky conditions, significantly improve performance in differential mode. Accuracy in vehicular mode using code and carrier phase differential RTK solution is at the level of a few to several dm. Tests were conducted in parallel with a Huawei P10 Android 8.0 smartphone. The code measurement noise of this unit was found to be significantly higher than that of the GPSMap 66, a major reason being its lower performance PIFA antenna; carrier phase was only available for short time intervals, significantly degrading differential position accuracy performance.
Qualitative Dynamics of Suspended Particulate Matter in the Changjiang Estuary from Geostationary Ocean Color Images: An Empirical, Regional Modeling Approach
Authors: Shang Dinghui , Xu Huiping
Published: November 2018

The suspended particulate matter (SPM) in Changjiang Estuary is characterized by a high concentration of significant diurnal dynamics. With a higher temporal resolution (eight images obtained per day), Geostationary Ocean Color Imager (GOCI) was selected as the primary remote sensor for the dynamics monitoring in this paper, instead of other satellite sensor working in polar orbit. Based on the characteristics of the field spectra measured in the estuary, an empirical model was established with the band ratio of Rrs745 divided by Rrs490 and proven effective in Suspended Particulate Matter (SPM) estimation (R2 = 0.9376, RMSE = 89.32 mg/L). While, Validation results showed that the model performed better in coastal turbid waters than offshore clear waters with higher chlorophyll-a concentration, stressing the importance of partitioning SPM into its major components and doing separate analysis. The hourly observations from GOCI showed that the diurnal variation magnitudes exhibited clear regional characteristics, with a maximum in the turbidity belt near the mouth and a minimum in the offshore deeper areas. In addition, comparing the monthly averaged SPM distribution with the amount of sediment discharged into the estuary, the variation in estuarine turbidity maximum zone is more likely contributed by the sediments resuspended from the sea bed that has already accumulated in the estuarine delta.
Multi-UAV Path Planning for Autonomous Missions in Mixed GNSS Coverage Scenarios
Authors: Causa Flavia , Fasano Giancarmine , Grassi Michele
Published: November 2018

This paper presents an algorithm for multi-UAV path planning in scenarios with heterogeneous Global Navigation Satellite Systems (GNSS) coverage. In these environments, cooperative strategies can be effectively exploited when flying in GNSS-challenging conditions, e.g., natural/urban canyons, while the different UAVs can fly as independent systems in the absence of navigation issues (i.e., open sky conditions). These different flight environments are taken into account at path planning level, obtaining a distributed multi-UAV system that autonomously reconfigures itself based on mission needs. Path planning, formulated as a vehicle routing problem, aims at defining smooth and flyable polynomial trajectories, whose time of flight is estimated to guarantee coexistence of different UAVs at the same challenging area. The algorithm is tested in a simulation environment directly derived from a real-world 3D scenario, for variable number of UAVs and waypoints. Its solution and computational cost are compared with optimal planning methods. Results show that the computational burden is almost unaffected by the number of UAVs, and it is compatible with near real time implementation even for a relatively large number of waypoints. The provided solution takes full advantage from the available flight resources, reducing mission time for a given set of waypoints and for increasing UAV number.
Special Issue: Community Development for Equity and Empowerment
Authors: Silverman Robert Mark
Published: November 2018

In cities and settlements across the world, calls for equitable community development policy are unparalleled. [...]
What Parents Can Do to Prevent Cyberbullying: Students’ and Educators’ Perspectives
Authors: Cassidy Wanda , Faucher Chantal , Jackson Margaret
Published: November 2018

This article presents findings related to the role parents can play in the prevention of cyberbullying and the promotion of cyber-kindness. The findings are drawn from a study conducted at a private school in Western Canada, involving 177 student survey participants in Grades 8 through 10 (including both day students and boarding students) and interviews with 15 educators employed at the same school. Findings relate to parental supervision of computer usage, students’ willingness to inform parents about cyberbullying, and how students and educators view the role of parents in relation to the prevention of cyberbullying and the promotion of cyber-kindness. Education, dialogue, relationship strengthening, computer usage monitoring, and partnerships between schools and parents are emphasized as solutions, which are highly consistent with the existing research literature on this topic. Additionally, the study reveals the particular vulnerability of boarding students to cyberbullying victimization and perpetration.
Dynamic Relationships between Mega Projects and Official Development Assistance: Case of South Korean Infrastructure Construction Projects in ASEAN’s Developing Countries
Authors: Lee Suk-Won , Jeon Jae-Keun
Published: November 2018

In developing countries, infrastructure construction projects are sometimes recognized as mega projects that are important for national development. Such projects are usually implemented as official development assistance (ODA). However, the correlation between the size of ODA and the infrastructure construction project orders gained cannot be completely confirmed. South Korea gives constant aid to developing countries and increases the budget of ODA simultaneously in order to select which country’s construction market to advance. The largest portion of South Korea’s aid continues to be provided to Asian countries. This study analyzes the dynamic relationship between South Korea’s ODA to the Association of Southeast Asian Nations (ASEAN) developing countries and the economic fluctuations represented by infrastructure construction projects, gross domestic product (GDP), gross national income (GNI), and foreign direct investment (FDI). The analysis result shows that the scale of ODA is synergistic to the number of infrastructure construction project orders awarded. In other words, as ODA increases, developing countries can continue to construct infrastructure, and South Korean companies can improve their performance in overseas construction projects in cooperation with those countries. The results of this study can be used as basic data for the decision-making of donor countries when selecting a country’s construction market to advance.
Path Loss Model for Outdoor Parking Environments at 28 GHz and 38 GHz for 5G Wireless Networks
Authors: Al-Samman Ahmed M. , Rahman Tharek Abd , Hindia MHD Nour , Daho Abdusalama , Hanafi Effariza
Published: November 2018

It has been widely speculated that the performance of the next generation Internet of Things (IoT) based wireless network should meet a transmission speed on the order of 1000 times more than current wireless networks; energy consumption on the order of 10 times less and access delay of less than 1 ns that will be provided by future 5G systems. To increase the current mobile broadband capacity in future 5G systems, the millimeter wave (mmWave) band will be used with huge amounts of bandwidth available in this band. Hence, to support this wider bandwith at the mmWave band, new radio access technology (RAT) should be provided for 5G systems. The new RAT with symmetry design for downlink and uplink should support different scenarios such as device to device (D2D) and multi-hop communications. This paper presents the path loss models in parking lot environment which represents the multi-end users for future 5G applications. To completely assess the typical performance of 5G wireless network systems across these different frequency bands, it is necessary to develop path loss (PL) models across these wide frequency ranges. The short wavelength of the highest frequency bands provides many scatterings from different objects. Cars and other objects are some examples of scatterings, which represent a critical issue at millimeter-wave bands. This paper presents the large-scale propagation characteristics for millimeter-wave in a parking lot environment. A new physical-based path loss model for parking lots is proposed. The path loss was investigated based on different models. The measurement was conducted at 28 GHz and 38 GHz frequencies for different scenarios. Results showed that the path loss exponent values were approximately identical at 28 GHz and 38 GHz for different scenarios of parking lots. It was found that the proposed compensation factor varied between 10.6 dB and 23.1 dB and between 13.1 and 19.1 in 28 GHz and 38 GHz, respectively. The proposed path loss models showed that more compensation factors are required for more scattering objects, especially at 28 GHz.
Influence of Irradiance and Temperature on the Virus MpoV-45T Infecting the Arctic Picophytoplankter Micromonas polaris
Authors: Piedade Gonçalo J. , Wesdorp Ella M. , Montenegro-Borbolla Elena , Maat Douwe S. , Brussaard Corina P. D.
Published: November 2018

Arctic marine ecosystems are currently undergoing rapid changes in temperature and light availability. Picophytoplankton, such as Micromonas polaris, are predicted to benefit from such changes. However, little is known about how these environmental changes affect the viruses that exert a strong mortality pressure on these small but omnipresent algae. Here we report on one-step infection experiments, combined with measurements of host physiology and viability, with 2 strains of M. polaris and the virus MpoV-45T under 3 light intensities (5, 60 and 160 μmol quanta m−2 s−1), 2 light period regimes (16:8 and 24:0 h light:dark cycle) and 2 temperatures (3 and 7 °C). Our results show that low light intensity (16:8 h light:dark) delayed the decline in photosynthetic efficiency and cell lysis, while decreasing burst size by 46%. In contrast, continuous light (24:0 h light:dark) shortened the latent period by 5 h for all light intensities, and even increased the maximum virus production rate and burst size under low light (by 157 and 69%, respectively). Higher temperature (7 °C vs 3 °C) led to earlier cell lysis and increased burst size (by 19%), except for the low light conditions. These findings demonstrate the ecological importance of light in combination with temperature as a controlling factor for Arctic phytoplankton host and virus dynamics seasonally, even more so in the light of global warming.
Un spectroscope pour résonances piézoélectriques et nucléaires
Authors: Coeuré Philippe
Published: November 2018

On décrit un appareil susceptible de déceler la piézo˗électricité d'un corps cristallin à l'état de poudre fine, par l'absorption à la résonance dans la sonde˗condensateur du circuit oscillant d'un oscillateur. Cette résonance (dans un domaine de 6 à 40 MHz) est directement affichée sur l'écran oscilloscopique incorporé à l'appareil.

L'appareil réalisé, robuste et compact, s'avère particulièrement sensible et d'un emploi facile. Son usage peut être rendu à l'observation de raies de résonances paramagnétiques et piézomagnétiques grâce à l'adjonction d'une sonde de type « self ».
Étude cristallographique de nouveaux sulfures de terres rares et de métaux alcalins M = Li, K
Authors: Ballestracci Régis
Published: November 2018

On décrit de nouveaux sulfures de terres rares et de métaux alcalins (Li, K). Les composés TLiS₂ (T = Pr à Y) ont une structure cubique du type NaCl, les atomes T et Li étant désordonnés ; pour les terres rares de rayons plus petits (Ho, Er, Yb), les atomes T et Li s'ordonnent et il apparaît une déformation rhomboédrique dans le groupe R[-3] m (type α FeNaO₂), les composés LaLiS₂ et CeLiS₂ n'existent pas.

Tous les sulfures TKS₂ (T = La à Yb) sont ordonnés et cristallisent avec la structure rhomboédrique précédente. Les sulfures de terres rares et de métaux alcalins forment une famille très homogène ; on étudie les domaines d'existence de chaque phase en fonction des rayons atomiques.
Paramètres atomiques et structures magnétiques de UCrO4
Authors: Bacmann Madeleine , Lewy-Bertaut Erwin Félix , Bassi Gérard
Published: November 2018

La diffraction neutronique nucléaire permet de préciser les coordinences octaédriques de Cr et de U dans UCrO₄ orthorhombique (a = 4,87₁ Å ; b = 11,78₇ Å ; c = 5,05₃ Å ; groupe Pbcn). Cr est à l'état trivalent, U à l'état pentavalent. La diffraction neutronique magnétique à 4°,2 K montre un arrangement antiferromagnétique avec des liaisons Cr˗Cr et Cr˗O˗U négatives. Les valeurs observées des spins Sobs. (Cr) = 1,20 ± 0,05, Sobs. (U) = 0,15 ± 0,02 sont considérablement réduites par des effets de covalence par rapport aux valeurs théoriques de spin seul Sth (Cr³⁺) = 3/2 et Sth (U⁵⁺) = 1/2.
La jouravskite, une nouvelle espèce minérale
Authors: Gaudefroy Christophe , Permingeat François
Published: November 2018

Hexagonale P6₃ ou P6 ₃/m ; a = 11,06 ± 0,03 ; c = 10,50 ± 0,03 Å ; z = 1. Apparentée à la thaumasite. Principales raies du diagramme de poudre (très voisin de celui de la thaumasite) : 9,6 FFF, 5,53 F, 3,81 F, 3,42 mF, 2,73 mF, 2,52 mF, 2,17 mF. Se présente en mouches jaunes à orangé verdâtre de 1 à 5 mm, constituées de grains de quelques dixièmes de mm, présentant 3 bons clivages m (10. o) mais très rarement des formes propres avec m et b² (10.2). Fragile. Dureté 21/2 ; dmes = 1,95 ± 0,01 ; dx = 1,93 ± 0,02. Transparente et colorée en jaune vif, non pléochroïque. Teintes de polarisation très anormales : il n'apparaît que du vert, du vert˗jaunâtre et du roux jusque dans les ordres supérieurs. Uniaxe négative. n₀ = 1,556 ; ne = 1,540 (± 0,002). L'analyse chimique sur un échantillon de 1 g environ, soigneusement trié et contrôlé, conduit à la formule : Ca₆Mn⁴⁺₂ [SO₄/(S₀,₇, C₀,₃) (O, OH)₄/(CO₃)₂/(OH)₁₂. 24H₂O

ou peut-être, par analogie avec la thaumasite : Ca₆H₄ [SO₄/(S₀,₇, C₀,₃) (O, OH)₄/(CO₃)₂/(MnO₄)⁴⁻₂]. 28H₂O

La composition chimique peut probablement varier quelque peu d'un échantillon à l'autre. Les courbes d'analyse thermique différentielle et thermopondérale montrent une déshydratation brutale dès 100° puis diverses transformations. La jouravskite a été trouvée dans le filon 2 du gîte de manganèse de Tachgagalt (Anti˗Atlas, Maroc), associée à : calcite, manganite, marokite, gaudefroyite et barytine. Les échantillons-types sont conservés à Paris. Le nom est proposé en mémoire de G. Jouravsky (1896-1964).
Le problème du plomb dans certaines aragonites plombifères
Authors: Goñi Juan C. , Pierrot Roland , Passaqui Bernard
Published: November 2018

Une aragonite plombifère (5,1 % de PbO) provenant de Castelminier a été étudiée à l'aide de la microsonde électronique. Il est montré que le plomb est localisé dans le champ fissural de l'aragonite et fixé par des produits d'aspect colloïdal. La présence possible du plomb dans le réseau de l'aragonite est au plus de l'ordre de 0,1 %.

Par comparaison, l'étude d'une aragonite plombifère (7,5 % de PbO) de Tsumeb (tarnowitzite) a permis de montrer que dans ce cas, le plomb était sous forme de cérusite en inclusion de l'ordre du micron dans l'aragonite.

L'existence généralement admise d'un remplacement isomorphe du calcium par le plomb dans l'aragonite est discutée.