bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of Micro-Scale 3D Printing in Pharmaceutics
Authors: Kjar Andrew , Huang Yu
Published: August 2019

3D printing, as one of the most rapidly-evolving fabrication technologies, has released a cascade of innovation in the last two decades. In the pharmaceutical field, the integration of 3D printing technology has offered unique advantages, especially at the micro-scale. When printed at a micro-scale, materials and devices can provide nuanced solutions to controlled release, minimally invasive delivery, high-precision targeting, biomimetic models for drug discovery and development, and future opportunities for personalized medicine. This review aims to cover the recent advances in this area. First, the 3D printing techniques are introduced with respect to the technical parameters and features that are uniquely related to each stage of pharmaceutical development. Then specific micro-sized pharmaceutical applications of 3D printing are summarized and grouped according to the provided benefits. Both advantages and challenges are discussed for each application. We believe that these technologies provide compelling future solutions for modern medicine, while challenges remain for scale-up and regulatory approval.
Functional Role of VCAM-1 Targeted Flavonoid-Loaded Lipid Nanoemulsions in Reducing Endothelium Inflammation
Authors: Fuior Elena , Deleanu Mariana , Constantinescu Cristina , Rebleanu Daniela , Voicu Geanina , Simionescu Maya , Calin Manuela
Published: August 2019

Citrus flavonoids have well-documented protective effects on cardiovascular system, but the poor water solubility and reduced bioavailability restrict their therapeutic use. We aimed to overcome these limitations and encapsulated naringenin and hesperetin into lipid nanoemulsions (LNs), targeted to vascular cell adhesion molecule-1 (VCAM-1), which is expressed on activated endothelial cells (ECs). LNs were characterized by a hydrodynamic size of ~200 nm, negative zeta potential, an encapsulation efficiency of flavonoids higher than 80%, good in vitro stability and steady release of the cargo. The LNs were neither cytotoxic to human ECs line EA.hy926, nor provoked in vitro lysis of murine erithrocytes. Then, we tested whether these nanoformulations reduce tumor necrosis factor-alpha (TNF-α) induced EC-activation. We found that flavonoid-loaded LNs, either non-targeted or targeted to the endothelium, were taken up by the EA.hy926 cells in a dose-dependent manner, but dependent on TNF-α only in the case of endothelium-targeted LNs. Moreover, these nanoparticles inhibited both the adhesion and transmigration of THP-1 monocytes on/through activated ECs, by mechanisms involving a reduced expression of the pro-inflammatory chemokine monocyte chemotactic protein 1 (MCP-1) and diminished nuclear translocation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB).
Pharmacokinetic Profile and Anti-Adhesive Effect of Oxaliplatin-PLGA Microparticle-Loaded Hydrogels in Rats for Colorectal Cancer Treatment
Authors: Abuzar Sharif Md , Ahn Jun-Hyun , Park Kyung Su , Park Eun Jung , Baik Seung Hyuk , Hwang Sung-Joo
Published: August 2019

Colorectal cancer (CRC) is one of the most malignant and fatal cancers worldwide. Although cytoreductive surgery combined with chemotherapy is considered a promising therapy, peritoneal adhesion causes further complications after surgery. In this study, oxaliplatin-loaded Poly-(d,l-lactide-co-glycolide) (PLGA) microparticles were prepared using a double emulsion method and loaded into hyaluronic acid (HA)- and carboxymethyl cellulose sodium (CMCNa)-based cross-linked (HC) hydrogels. From characterization and evaluation study PLGA microparticles showed smaller particle size with higher entrapment efficiency, approximately 1100.4 ± 257.7 nm and 77.9 ± 2.8%, respectively. In addition, microparticle-loaded hydrogels showed more sustained drug release compared to the unloaded microparticles. Moreover, in an in vivo pharmacokinetic study after intraperitoneal administration in rats, a significant improvement in the bioavailability and the mean residence time of the microparticle-loaded hydrogels was observed. In HC21 hydrogels, AUC0–48h, Cmax, and Tmax were 16012.12 ± 188.75 ng·h/mL, 528.75 ± 144.50 ng/mL, and 1.5 h, respectively. Furthermore, experimental observation revealed that the hydrogel samples effectively protected injured tissues from peritoneal adhesion. Therefore, the results of the current pharmacokinetic study together with our previous report of the in vivo anti-adhesion efficacy of HC hydrogels demonstrated that the PLGA microparticle-loaded hydrogels offer novel therapeutic strategy for CRC treatment.
BMP-2 Gene Delivery-Based Bone Regeneration in Dentistry
Authors: Park Shin-Young , Kim Kyoung-Hwa , Kim Sungtae , Lee Yong-Moo , Seol Yang-Jo
Published: August 2019

Bone morphogenetic protein-2 (BMP-2) is a potent growth factor affecting bone formation. While recombinant human BMP-2 (rhBMP-2) has been commercially available in cases of non-union fracture and spinal fusion in orthopaedics, it has also been applied to improve bone regeneration in challenging cases requiring dental implant treatment. However, complications related to an initially high dosage for maintaining an effective physiological concentration at the defect site have been reported, although an effective and safe rhBMP-2 dosage for bone regeneration has not yet been determined. In contrast to protein delivery, BMP-2 gene transfer into the defect site induces BMP-2 synthesis in vivo and leads to secretion for weeks to months, depending on the vector, at a concentration of nanograms per milliliter. BMP-2 gene delivery is advantageous for bone wound healing process in terms of dosage and duration. However, safety concerns related to viral vectors are one of the hurdles that need to be overcome for gene delivery to be used in clinical practice. Recently, commercially available gene therapy has been introduced in orthopedics, and clinical trials in dentistry have been ongoing. This review examines the application of BMP-2 gene therapy for bone regeneration in the oral and maxillofacial regions and discusses future perspectives of BMP-2 gene therapy in dentistry.
A Convenient Plant-Based Detection System to Monitor Androgenic Compound in the Environment
Authors: Kim Dong-Gwan , Bahmani Ramin , Ko Jae-Heung , Hwang Seongbin
Published: August 2019

Environmental androgen analogues act as endocrine disruptors, which inhibit the normal function of androgen in animals. In the present work, through the expression of a chimeric gene specified for the production of the anthocyanin in response to androgen DHT (dihydrotestosterone), we generated an indicator Arabidopsis that displays a red color in leaves in the presence of androgen compounds. This construct consists of a ligand-binding domain of the human androgen receptor gene and the poplar transcription factor gene PtrMYB119, which is involved in anthocyanin biosynthesis in poplar and Arabidopsis. The transgenic Arabidopsis XVA-PtrMYB119 displayed a red color in leaves in response to 10 ppm DHT, whereas it did not react in the presence of other androgenic compounds. The transcript level of PtrMYB119 peaked at day 13 of DHT exposure on agar media and then declined to its normal level at day 15. Expressions of anthocyanin biosynthesis genes including chalcone flavanone isomerase, chalcone synthase, flavanone 3-hydroxylase, dihydroflavonol 4-reductase, UFGT (UGT78D2), and anthocyanidin synthase were similar to that of PtrMYB119. It is assumed that this transgenic plant can be used by nonscientists for the detection of androgen DHT in the environment and samples such as food solution without any experimental procedures.
Improving Oxygen Permeability and Thermostability of Polycarbonate via Copolymerization Modification with Bio-Phenol Polysiloxane
Authors: Pang Xiaoyan , Ge Xin , Ji Jianye , Liang Weijie , Liu Ruoling , Chen Xunjun , Yin Guoqiang , Ge Jianfang
Published: August 2019

As a new kind of functionalized polysiloxane with chemical reactivity, bio-phenol polysiloxane was synthesized through facile heterogeneous catalytic route. Bio-phenol polysiloxane/polycarbonate (Si/PC) block copolymer was synthesized via a three-step approach, and the effect of the amount of bio-phenol polysiloxane on the properties of Si/PC copolymer was then studied. The structure and morphology of Si/PC copolymer were characterized, showing that, when the amount of bio-phenol polysiloxane reached 20%, the pyrolysis temperature of Si/PC copolymer at 5% weight loss was 450.8 °C which was 76.1 °C higher than pure PC. The oxygen permeability of 20%Si/PC copolymer membrane was 502.65 cm3/m2·24h·0.1MPa, which was increased by 128.4% compared with pure PC membrane. The mechanical property and hydrophobicity of Si/PC copolymer had been improved.
Flame Retardancy and Mechanism of Novel Phosphorus-Silicon Flame Retardant Based on Polysilsesquioxane
Authors: Zhu Shengjie , Gong Weiguang , Luo Ji , Meng Xin , Xin Zhong , Wu Jie , Jiang Zewen
Published: August 2019

A novel phosphorus-silicon flame retardant (P5PSQ) was prepared by bonding phosphate to silicon-based polysilsesquioxane (PSQ) and used as flame retardant of poly (lactic acid) (PLA). The results show that PLA with 10 wt % P5PSQ has a limiting oxygen index (LOI) 24.1%, the peak heat release rate (PHRR) and total heat release (THR) of PLA decrease 21.8% and 25.2% compared to neat PLA in cone calorimetric test, indicating that P5PSQ shows better flame retardancy in comparison to PSQ. Furthermore, the study for the morphology and composition of carbon residue after the combustion of PLA and the gas release of PLA during combustion illustrate that P5PSQ has flame retardancy in condensed phase and gas phase simultaneously. In condensed phase, phosphorus from phosphate promotes the formation of more stable and better carbon layer containing Si and P, which inhibits the transfer of heat and oxygen in the combustion. In gas phase, the phosphate in P5PSQ emits phosphorus-containing compound that can restrain the release of C–O containing products, which may have effective flame retardancy for PLA in gas phase to a certain extent. In one word, P5PSQ is denoted as a good phosphorus-silicon synergistic flame-retardant.
Cationic Fluorescent Nanogel Thermometers based on Thermoresponsive Poly(N-isopropylacrylamide) and Environment-Sensitive Benzofurazan
Authors: Hayashi Teruyuki , Kawamoto Kyoko , Inada Noriko , Uchiyama Seiichi
Published: August 2019

Cationic nanogels of N-isopropylacrylamide (NIPAM), including NIPAM-based cationic fluorescent nanogel thermometers, were synthesized with a cationic radical initiator previously developed in our laboratory. These cationic nanogels were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), zeta potential measurements and fluorescence spectroscopy, as summarized in the temperature-dependent fluorescence response based on the structural change in polyNIPAM units in aqueous solutions. Cellular experiments using HeLa (human epithelial carcinoma) cells demonstrated that NIPAM-based cationic fluorescent nanogel thermometers can spontaneously enter the cells under mild conditions (at 25 °C for 20 min) and can show significant fluorescence enhancement without cytotoxicity with increasing culture medium temperature. The combination of the ability to enter cells and non-cytotoxicity is the most important advantage of cationic fluorescent nanogel thermometers compared with other types of fluorescent polymeric thermometers, i.e., anionic nanogel thermometers and cationic/anionic linear polymeric thermometers.
Effect of Semi-Conductive Layer Modified by Magnetic Particle SrFe12O19 on Charge Injection Characteristics of HVDC Cable
Authors: Wei Yanhui , Liu Mingyue , Wang Jiaxing , Li Guochang , Hao Chuncheng , Lei Qingquan
Published: August 2019

For high voltage direct current (HVDC) cable, a semi-conductive layer lies between the conductor and the insulation layer; as the charge migrates the path from the conductor to the insulation material, it will affect space charge injection. In this work, the research idea of changing the injection path of moving charges within semi-conductive layer by magnetic particles was proposed. Semi-conductive composites with different SrFe12O19 contents of 1 wt.%, 5 wt.%, 10 wt.%, 20 wt.%, and 30 wt.% were prepared, and the amount of injected charges in the insulation sample was characterized by space charge distribution, polarization current, and thermally-stimulated depolarization current. The experimental results show that a small amount of SrFe12O19 can significantly reduce charge injection in the insulation sample, owing to the deflection of the charge migration path, and only part of the electrons can enter the insulation sample. When the content is 5 wt.%, the insulation sample has the smallest charge amount, 0.89 × 10−7 C, decreasing by 37%, and the steady-state current is 6.01 × 10−10 A, decreasing by 22%. When SrFe12O19 content exceeds 10 wt.%, the charge suppression effect is not obvious and even leads to the increase of charge amount in the insulation sample, owing to the secondary injection of charges. Most moving charges will deflect towards the horizontal direction and cannot direct access to the insulation sample, resulting in a large number of charges accumulation in the semi-conductive layer. These charges will seriously enhance the interface electric field near the insulation sample, leading to the secondary injection of charges, which are easier to inject into the insulation sample.
Formation and Evolution Mechanism for Carbonaceous Deposits on the Surface of a Coking Chamber
Authors: Wang Hao , Jin Baosheng , Wang Xiaojia , Tang Gang
Published: August 2019

This work aimed to investigate the carbonaceous deposits on the surface of the coking chamber. Scanning electron microscopy (SEM), X-ray fluorescence spectrum (XRF), Fourier transform infrared spectrometer (FTIR), Raman spectroscopy, X-ray diffraction spectrum (XRD), and X-ray photoelectron spectroscopy (XPS) were applied to investigate the carbonaceous deposits. FTIR revealed the existence of carboxyl, hydroxyl, and carbonyl groups in the carbonaceous deposits. SEM showed that different carbonaceous deposit layers presented significant differences in morphology. XRF and XPS revealed that the carbonaceous deposits mainly contained C, O, and N elements, with smaller amounts of Al, Si, and Ca elements. It was found that in the formation of carbonaceous deposits, the C content gradually increased while the O and N elements gradually decreased. It was also found that the absorbed O2 and H2O took part in the oxidation process of the carbon skeleton to form the =O and –O– structure. The oxidation and elimination reaction resulted in change in the bonding state of the O element, and finally formed compact carbonaceous deposits on the surface of the coking chamber. Based on the analysis, the formation and evolution mechanisms of carbonaceous deposits were discussed.
Robust Process Design in Pharmaceutical Manufacturing under Batch-to-Batch Variation
Authors: Xie Xiangzhong , Schenkendorf René
Published: August 2019

Model-based concepts have been proven to be beneficial in pharmaceutical manufacturing, thus contributing to low costs and high quality standards. However, model parameters are derived from imperfect, noisy measurement data, which result in uncertain parameter estimates and sub-optimal process design concepts. In the last two decades, various methods have been proposed for dealing with parameter uncertainties in model-based process design. Most concepts for robustification, however, ignore the batch-to-batch variations that are common in pharmaceutical manufacturing processes. In this work, a probability-box robust process design concept is proposed. Batch-to-batch variations were considered to be imprecise parameter uncertainties, and modeled as probability-boxes accordingly. The point estimate method was combined with the back-off approach for efficient uncertainty propagation and robust process design. The novel robustification concept was applied to a freeze-drying process. Optimal shelf temperature and chamber pressure profiles are presented for the robust process design under batch-to-batch variation.
Determination of the Potential Impact of Domestic Anaerobic Digester Systems: A Community Based Research Initiative in Rural Bangladesh
Authors: Rahman Khondokar M. , Melville Lynsey , Edwards David J. , Fulford David , Thwala Wellington Didibhuku
Published: August 2019

This research examines the potential impact of domestic anaerobic digester (AD) systems adopted in Bangladesh and similar developing countries. Cattle dung and poultry litter feed stocks were specifically investigated, because these were freely available and plentiful to people living within agricultural areas of rural Bangladesh. Data was collected to ascertain whether these two representative AD facility types provide tangible social, economic and environmental impact that benefits homeowners. Primary quantitative and qualitative data was obtained by field data collection, and meeting with expert groups and stakeholders. Empirical analysis conducted revealed that variations were found in the biomass feedstocks available on different sites but also differences were apparent in terms of the operations and maintenance (O and M) systems of the biogas plants operated. The biogas and methane yield variation was also measured, and variations were found in the cattle dung and poultry litter AD yield capacity. Overall, 64% of feedstock was utilised, 91% of biogas plants remain underfed and energy yield efficiency was 57% from cattle smallholdings’ AD and 28% from poultry farms’ AD. These results showed that small scale AD can offer a significant impact upon rural lifestyles through augmented economics, improved social activities, relationship building with neighbours and improved lifestyle achieved via time savings accrued. These results could help rural entrepreneurs, AD equipment providers and government institutions to develop a road map to implement future AD installation on a much wider geographical scale.
Glycoalkaloids: Structure, Properties, and Interactions with Model Membrane Systems
Authors: Nepal Bishal , J. Stine Keith
Published: August 2019

The glycoalkaloids which are secondary metabolites from plants have proven to be of significant interest for their biological properties both in terms of their roles in plant biology and the effects they exhibit when ingested by humans. The main feature of the action of glycoalkaloids is their strong binding to 3β-hydroxysterols, such as cholesterol, to form complexes with the consequence that membrane structure is significantly perturbed, and leakage or release of contents inside cells or liposomes becomes possible. The glycoalkaloids have been studied for their ability to inhibit the growth of cancer cells and in other roles such as vaccine adjuvants and as synergistic agents when combined with other therapeutics. The glycoalkaloids have rich and complex physical behavior when interacting with model membranes for which many aspects are yet to be understood. This review introduces the general properties of glycoalkaloids and aspects of their behavior, and then summarizes their effects against model membrane systems. While there are many glycoalkaloids that have been identified, most physical or biological studies have focused on the readily available ones from tomatoes (α-tomatine), potatoes (α-chaconine and α-solanine), and eggplant (α-solamargine and α-solasonine).
Near-Wall Flow Characteristics of a Centrifugal Impeller with Low Specific Speed
Authors: Cao Weidong , Jia Zhixiang , Zhang Qiqi
Published: August 2019

In order to study the near-wall region flow characteristics in a low-specific-speed centrifugal impeller, based on ANSYS-CFX 15.0 software, Reynolds averaged Navier-Stokes (RANS) methods and renormalization group (RNG) k-ɛ turbulence model were used to simulate the whole flow field of a low specific speed centrifugal pump with five blades under different flow rates. Simulation results of external characteristics of the pump were in good agreement with experimental results. Profiles were set on the pressure side and suction side of impeller blades at the distances of 0.5 mm and 2 mm, respectively, to study the distributions of flow characteristics near the wall region of five groups of blades. The results show that the near-wall region flow characteristics of five groups of blades were similar, but the static pressure, relative velocity, cross flow velocity, and turbulent kinetic energy of profiles on the pressure side were quite different to those on the suction sides, and these characteristics also changed with the alternation of flow rate. As the flow rate was 13 m3/h or 20 m3/h, within the radius range of 40 to 50 mm, there was an extent of negative relative velocity of the profiles on the pressure side, and a counter-current happened not on the suction side, but on the pressure side in the low specific speed centrifugal impeller. The flow characteristics of profiles at the distances of 0.5 mm and 2 mm also showed a small difference.
Haiti’s Pact with the Devil?: Bwa Kayiman, Haitian Protestant Views of Vodou, and the Future of Haiti
Authors: Louis Jr. Bertin M.
Published: August 2019

This essay uses ethnographic research conducted among Haitian Protestants in the Bahamas in 2005 and 2012 plus internet resources to document the belief among Haitian Protestants (Haitians who practice Protestant forms of Christianity) that Haiti supposedly made a pact with the Devil (Satan) as the result of Bwa Kayiman, a Vodou ceremony that launched the Haitian Revolution (1791–1803). Vodou is the syncretized religion indigenous to Haiti. I argue that this interpretation of Bwa Kayiman is an extension of the negative effects of the globalization of American Fundamentalist Christianity in Haiti and, by extension, peoples of African descent and the Global South.
Sustainable International Relations. Pope Francis’ Encyclical Laudato Si’ and the Planetary Implications of “Integral Ecology”
Authors: Ferrara Pasquale
Published: August 2019

This paper analyzes the theoretical and pragmatic implications for international relations and world politics of the new holistic approach to climate change articulated by Pope Francis in the Encyclical Laudato Si’, particularly through the notion of “integral ecology”. It is not my intention to offer an exegesis of the Papal document. I will rather try to illustrate and discuss its planetary hermeneutics. I emphasize that the Encyclical’s perspective is not exclusively normative, and that, within the dynamic interplay between social structure and human agency, it can also be considered as a call to action. In this context, I suggest that both International Relations Theory and global politics have much to learn from the fundamental claims of contemporary religions in relation to climate disruption. In particular, Pope Francis’ document, far from being just a new chapter in the unfolding process of the “greening” of religions, raises the issue of the sustainability of the present world system. Therefore, I contend that the perspective of the Encyclical calls for a radical transformation of international relations, since it emphasizes the deep implications of environmental issues on the entire spectrum of security, development, economic and ethical challenges of contemporary world politics. Against this backdrop, my objective is to connect the main tenets of the Encyclical to the environmental turn in International Relations Theory and to the new epistemological challenges related to the paradigm shift induced by the new planetary condition of the Anthropocene and the relevant questions arising for a justice encompassing the humanity-earth system. The Encyclical seems to suggest that practicing sustainable international relations means exiting the logic of power or hegemony, while simultaneously operationalizing the concept of care.
Reconfiguration Analysis of a 3-DOF Parallel Mechanism
Authors: Ruggiu Maurizio , Kong Xianwen
Published: August 2019

This paper deals with the reconfiguration analysis of a 3-DOF (degrees-of-freedom) parallel manipulator (PM) which belongs to the cylindrical parallel mechanisms family. The PM is composed of a base and a moving platform shaped as equilateral triangles connected by three serial kinematic chains (legs). Two legs are composed of two universal (U) joints connected by a prismatic (P) joint. The third leg is composed of a revolute (R) joint connected to the base, a prismatic joint and universal joint in sequence. A set of constraint equations of the 1-RPU−2-UPU PM is derived and solved in terms of the Euler parameter quaternion (a.k.a. Euler-Rodrigues quaternion) representing the orientation of the moving platform and of the Cartesian coordinates of the reference point on the moving platform. It is found that the PM may undergo either the 3-DOF PPR or the 3-DOF planar operation mode only when the base and the moving platform are identical. The transition configuration between the operation modes is also identified.
Chlorophyll Concentration Response to the Typhoon Wind-Pump Induced Upper Ocean Processes Considering Air–Sea Heat Exchange
Authors: Liu Yupeng , Tang Danling , Evgeny Morozov
Published: August 2019

The typhoon Wind-Pump induced upwelling and cold eddy often promote the significant growth of phytoplankton after the typhoon. However, the importance of eddy-pumping and wind-driven upwelling on the sea surface chlorophyll a concentration (Chl-a) during the typhoon are still not clearly distinguished. In addition, the air–sea heat flux exchange is closely related to the upper ocean processes, but few studies have discussed its role in the sea surface Chl-a variations under typhoon conditions. Based on the cruise data, remote sensing data, and model data, this paper analyzes the contribution of the vertical motion caused by the eddy-pumping upwelling and Ekman pumping upwelling on the surface Chl-a, and quantitatively analyzes the influence of air–sea heat exchange on the surface Chl-a after the typhoon Linfa over the northeastern South China Sea (NSCS) in 2009. The results reveal the Wind Pump impacts on upper ocean processes: (1) The euphotic layer-integrated Chl-a increased after the typhoon, and the increasing of the surface Chl-a was not only the uplift of the deeper waters with high Chl-a but also the growth of the phytoplankton; (2) The Net Heat Flux (air–sea heat exchange) played a major role in controlling the upper ocean physical processes through cooling the SST and indirectly increased the surface Chl-a until two weeks after the typhoon; (3) the typhoon-induced cyclonic eddy was the most important physical process in increasing the surface Chl-a rather than the Ekman pumping and wind-stirring mixing after typhoon; (4) the spatial shift between the surface Chl-a blooms and the typhoon-induced cyclonic eddy could be due to the Ekman transport; (5) nutrients uplifting and adequate light were two major biochemical elements supplying for the growth of surface phytoplankton.
Spatio–temporal Assessment of Drought in Ethiopia and the Impact of Recent Intense Droughts
Authors: Liou Yuei-An , Mulualem Getachew Mehabie
Published: August 2019

The recent droughts that have occurred in different parts of Ethiopia are generally linked to fluctuations in atmospheric and ocean circulations. Understanding these large-scale phenomena that play a crucial role in vegetation productivity in Ethiopia is important. In view of this, several techniques and datasets were analyzed to study the spatio–temporal variability of vegetation in response to a changing climate. In this study, 18 years (2001–2018) of Moderate Resolution Imaging Spectroscopy (MODIS) Terra/Aqua, normalized difference vegetation index (NDVI), land surface temperature (LST), Climate Hazards Group Infrared Precipitation with Stations (CHIRPS) daily precipitation, and the Famine Early Warning Systems Network (FEWS NET) Land Data Assimilation System (FLDAS) soil moisture datasets were processed. Pixel-based Mann–Kendall trend analysis and the Vegetation Condition Index (VCI) were used to assess the drought patterns during the cropping season. Results indicate that the central highlands and northwestern part of Ethiopia, which have land cover dominated by cropland, had experienced decreasing precipitation and NDVI trends. About 52.8% of the pixels showed a decreasing precipitation trend, of which the significant decreasing trends focused on the central and low land areas. Also, 41.67% of the pixels showed a decreasing NDVI trend, especially in major parts of the northwestern region of Ethiopia. Based on the trend test and VCI analysis, significant countrywide droughts occurred during the El Niño 2009 and 2015 years. Furthermore, the Pearson correlation coefficient analysis assures that the low NDVI was mainly attributed to the low precipitation and water availability in the soils. This study provides valuable information in identifying the locations with the potential concern of drought and planning for immediate action of relief measures. Furthermore, this paper presents the results of the first attempt to apply a recently developed index, the Normalized Difference Latent Heat Index (NDLI), to monitor drought conditions. The results show that the NDLI has a high correlation with NDVI (r = 0.96), precipitation (r = 0.81), soil moisture (r = 0.73), and LST (r = −0.67). NDLI successfully captures the historical droughts and shows a notable correlation with the climatic variables. The analysis shows that using the radiances of green, red, and short wave infrared (SWIR), a simplified crop monitoring model with satisfactory accuracy and easiness can be developed.
Random Noise Suppression of Magnetic Resonance Sounding Data with Intensive Sampling Sparse Reconstruction and Kernel Regression Estimation
Authors: Yao Xiaokang , Zhang Jianmin , Yu Zhenyang , Zhao Fa , Sun Yong
Published: August 2019

The magnetic resonance sounding (MRS) method is a non-invasive, efficient and advanced geophysical method for groundwater detection. However, the MRS signal received by the coil sensor is extremely susceptible to electromagnetic noise interference. In MRS data processing, random noise suppression of noisy MRS data is an important research aspect. We propose an approach for intensive sampling sparse reconstruction (ISSR) and kernel regression estimation (KRE) to suppress random noise. The approach is based on variable frequency sampling, numerical integration and statistical signal processing combined with kernel regression estimation. In order to realize the approach, we proposed three specific sparse reconstructions, namely rectangular sparse reconstruction, trapezoidal sparse reconstruction and Simpson sparse reconstruction. To solve the distortion of peaks and valleys after sparse reconstruction, we introduced the KRE to deal with the processed data by the ISSR. Further, the simulation and field experiments demonstrate that the ISSR-KRE approach is a feasible and effective way to suppress random noise. Besides, we find that rectangular sparse reconstruction and trapezoidal sparse reconstruction are superior to Simpson sparse reconstruction in terms of noise suppression effect, and sampling frequency is positively correlated with signal-to-noise improvement ratio (SNIR). In one case of field experiment, the standard deviation of noisy MRS data was reduced from 1200.80 nV to 570.01 nV by the ISSR-KRE approach. The proposed approach provides theoretical support for random noise suppression and contributes to the development of MRS instrument with low power consumption and high efficiency. In the future, we will integrate the approach into MRS instrument and attempt to utilize them to eliminate harmonic noise from power line.
Quasi Similar Routes of NO2 and NO Sensing by Nanocrystalline WO3: Evidence by In Situ DRIFT Spectroscopy
Authors: Yang Lili , Marikutsa Artem , Rumyantseva Marina , Konstantinova Elizaveta , Khmelevsky Nikolay , Gaskov Alexander
Published: August 2019

Tungsten oxide is a renowned material for resistive type gas sensors with high sensitivity to nitrogen oxides. Most studies have been focused on sensing applications of WO3 for the detection of NO2 and a sensing mechanism has been established. However, less is known about NO sensing routes. There is disagreement on whether NO is detected as an oxidizing or reducing gas, due to the ambivalent redox behavior of nitric oxide. In this work, nanocrystalline WO3 with different particle size was synthesized by aqueous deposition of tungstic acid and heat treatment. A high sensitivity to NO2 and NO and low cross-sensitivities to interfering gases were established by DC-resistance measurements of WO3 sensors. Both nitrogen oxides were detected as the oxidizing gases. Sensor signals increased with the decrease of WO3 particle size and had similar dependence on temperature and humidity. By means of in situ infrared (DRIFT) spectroscopy similar interaction routes of NO2 and NO with the surface of tungsten oxide were unveiled. Analysis of the effect of reaction conditions on sensor signals and infrared spectra led to the conclusion that the interaction of WO3 surface with NO was independent of gas-phase oxidation to NO2.
Investigation on Vortex-Induced Vibration Experiment of a Standing Variable-Tension Deepsea Riser Based on BFBG Sensor Technology
Authors: Li Peng , Cong Aijun , Dong Zhengkai , Wang Yu , Liu Yu , Guo Haiyan , Li Xiaomin , Fu Qiang
Published: August 2019

A vortex-induced vibration (VIV) experiment on a standing variable-tension deepsea riser was conducted to investigate the applicability and sensitivity of Bare Fiber Bragg Grating (BFBG) sensor technology for testing deepsea riser vibrations. The dominant frequencies, dimensionless displacements, in-line and cross-flow couplings of the riser VIV under different top tensions were observed through wavelet transform and modal decomposition. The result indicated that, excited by the same external flow velocities, the cross-flow and in-line dominant frequencies of the riser both decreased with increasing top tension. In terms of displacement responses, increasing top tension caused the root mean square (RMS) displacement to decrease and the vibration amplitude to reduce. In terms of cross-flow and in-line coupling, the closer a location is to the ends of the riser, the smaller the trajectory is and the more standard the “8” becomes. During top tension increases, there exists a “lag” in the time when the riser’s vibration trajectory becomes an “8”. The Slalom Surround Installation approach can effectively prevent the local breakage of the optical fiber string. BFBG sensor technology can give an accurate presentation of the displacement time history, vibration amplitude and frequency of the riser, provides a clear picture of how the riser’s mode and VIV evolve as a function of flow velocity.
PARSUC: A Parallel Subsampling-Based Method for Clustering Remote Sensing Big Data
Authors: Xia Huiyu , Huang Wei , Li Ning , Zhou Jianzhong , Zhang Dongying
Published: August 2019

Remote sensing big data (RSBD) is generally characterized by huge volumes, diversity, and high dimensionality. Mining hidden information from RSBD for different applications imposes significant computational challenges. Clustering is an important data mining technique widely used in processing and analyzing remote sensing imagery. However, conventional clustering algorithms are designed for relatively small datasets. When applied to problems with RSBD, they are, in general, too slow or inefficient for practical use. In this paper, we proposed a parallel subsampling-based clustering (PARSUC) method for improving the performance of RSBD clustering in terms of both efficiency and accuracy. PARSUC leverages a novel subsampling-based data partitioning (SubDP) method to realize three-step parallel clustering, effectively solving the notable performance bottleneck of the existing parallel clustering algorithms; that is, they must cope with numerous repeated calculations to get a reasonable result. Furthermore, we propose a centroid filtering algorithm (CFA) to eliminate subsampling errors and to guarantee the accuracy of the clustering results. PARSUC was implemented on a Hadoop platform by using the MapReduce parallel model. Experiments conducted on massive remote sensing imageries with different sizes showed that PARSUC (1) provided much better accuracy than conventional remote sensing clustering algorithms in handling larger image data; (2) achieved notable scalability with increased computing nodes added; and (3) spent much less time than the existing parallel clustering algorithm in handling RSBD.
Effect of Biochar on TDR-Based Volumetric Soil Moisture Measurements in a Loamy Sand Podzolic Soil
Authors: Wanniarachchi Dinushika , Cheema Mumtaz , Thomas Raymond , Galagedara Lakshman
Published: August 2019

Considering the increased interests in biochar (BC) as a soil amendment and a growing media substrate in agriculture, we evaluated the effect of BC incorporation on TDR (time-domain reflectometer)-based volumetric soil moisture content (VSMC) estimations in a loamy sand podzolic soil. Two commercial BC types (powdered—BCP, and granular—BCG) were mixed in different rates (w/w) with a podzolic soil. The dielectric constants measured using a TDR cable tester (MOHR CT 100) were converted to VSMC. Three commonly used models: (i) Topp’s equation, M-1; (ii) mixing model, M-2; and (iii) the forest soil model, M-3, were used. The accuracy of the estimated VSMC using these three models was statistically compared with measured VSMC. BCP at lower rates produced very similar results to the actual VSMC with M-1 and M-2 but deviated with increasing rates. The M-3 showed a non-linear relationship with measured VSMC. In BCG treatments, all models overestimated the VSMC. BCG rates higher than 15% (w/w) resulted in highly attenuated TDR waveforms and the signal was completely dissipated when rates higher than 50% (w/w) were used (typical application for field soils is less than 5% w/w). These results showed that predictions of the soil moisture content based on the soil dielectric constant might not be feasible for tested podzolic soils amended at high BC rates.
Communication Factors Affecting Tourist Adoption of Social Network Sites
Authors: Ho Chien-Ta Bruce , Gebsombut Nathatenee
Published: August 2019

Smart tourism technologies (STTs) are technological media that tourists apply in various stages of the tourism decision-making process. The purpose of this study was to explore how the communication elements of social network sites (SNSs), as a part of STTs, enhance tourists’ motivation and usage intention. A structural framework based on communication elements and the uses and gratification theory with regard to SNSs usage was developed and investigated. An online survey was employed for the data collection, and structural equation modeling was used in the hypotheses analysis. The findings indicated that Internet self-efficacy, information quality, and systems quality trigger the information-seeking motive while service quality and source credibility positively determine the relationship maintenance motive. The information-seeking motive, entertainment motive, relationship maintenance motive, and Internet self-efficacy positively influence the intention to use SNSs for trips. New findings were found in terms of the relationship between the motives. The information-seeking motive and relationship maintenance motive influence the entertainment motive. Moreover, the relationship maintenance motive influences the information-seeking motive.
Managerial Shareholding and CSR: Does Internal Control Quality Matter?—Evidence from China
Authors: Guo Mingyuan , Shen Shuyu
Published: August 2019

This paper uses the data of Corporate Social Responsibility (CSR) performance of A-share listed companies in China from 2013–2017 as sample to study on the impacts of managerial shareholding on CSR performance. By dividing the sample into mandatory disclosure group and voluntary disclosure group, we first empirically test the impacts of managerial shareholding on CSR performance. Then, we discuss the role of internal control quality in the impacts of managerial shareholding on CSR performance. Panel data models are employed in the empirical research and robust test. The empirical results show that: Firstly, in mandatory disclosure group, managerial shareholding has no significant impacts on CSR performance. In voluntary disclosure group, managerial shareholding has a positive impact on CSR performance. Secondly, in voluntary disclosure group, internal control quality has a positive role in the impacts of managerial shareholding on CSR performance, but this positive role cannot be supported empirically in mandatory disclosure group. Overall, these findings indicate that CSR performance is influenced by managerial shareholding and varies with CSR disclosure behaviors. The results of robust test also support this conclusion. Finally, we put forward that it would be a good choice for the companies to implement long-term equity incentives and improve internal control quality to promote CSR performance.
Measurement and Spatial Difference Analysis on the Accessibility of Road Networks in Major Cities of China
Authors: Zhang Xiaorui , Ren Andong , Chen Lihua , Zheng Xianyou
Published: August 2019

Given the current lack of accessibility research on road networks in 36 major cities in China, the accessibility and its spatial difference were measured by using space syntax and Moran index. The purpose is to provide an important decision-making basis for the Chinese government to grasp the accessibility level of China’s urban roads in general and formulate urban traffic development policies. The results show that the mean value of the global integration average is only 1.0009, indicating that the accessibility level is not optimistic in general. The accessibility of 36 major cities was divided into four levels: very low, low, high, and very high. Only four cities, namely Beijing, Shijiazhuang, Xi’an, and Zhengzhou, were at a very high level. The spatial differences of accessibility presented a spatial pattern of "middle-high, east-middle, and west-low". The global integration average, intelligibility, and synergy had significant global spatial autocorrelation, while the local spatial agglomeration distributions of these three indexes were dominated by high-high types. The five cities of Beijing, Shijiazhuang, Hohhot, Taiyuan, and Zhengzhou constituted the core area of high-value clustering of local spatial autocorrelation and presented a spatial form of inverted "T" shape. The research still has some limitations. The reasons for the low accessibility of developed cities, such as Guangzhou and Nanjing, are worth further analysis. Besides, the main possible influencing factors affecting accessibility, such as urban road density and spatial form, are also worthy of further analysis.
Plant Biodiversity Knowledge Varies by Gender in Sustainable Amazonian Agricultural Systems Called Chacras
Authors: Luzuriaga-Quichimbo Carmen X. , Hernández del Barco Míriam , Blanco-Salas José , Cerón-Martínez Carlos E. , Ruiz-Téllez Trinidad
Published: August 2019

Chacras, which are Amazonian agricultural systems, are examples of traditional agricultural management that are sustainable. They are also characteristic of the identities of different ethnographic groups in tropical America. However, information regarding the botanical characterization of chacras is scant. In tropical rural communities, there is a gender bias hypothesis that makes women potential reservoirs of traditional chacras plant knowledge. We present an experimental study in order to demonstrate if this knowledge difference really exists and to plan accordingly. We performed workshops in an isolated Kichwa community from Amazonian Ecuador. We calculated the cultural signififcance index (CSI) for 97 local flora plants. Our results revealed statistically significant differences. They were coherent with the Kichwa worldview and the structure of their society. We concluded that gender perspective must be taken into account in biodiversity conservation programs, such as, for example, those to implement the resilient agricultural practices of tropical contexts promoted by The United Nations Sustainable Development Goal 2 (SGD2).
Energy Efficiency for Supplier and Sustainability for Demand: A Case of Heating Systems in South Korea
Authors: Lee Chulseung , Park Jaechan , Lee Kangmun , Yang Ji Yeon , Roh Taewoo
Published: August 2019

This paper addresses an analysis of a recent debate in South Korea on energy efficiencies between a combined heat and power system with district heating (CHP-DH) and separate heat and power system (SHP) by applying a scenario analysis technique. In accordance with the Low Carbon Green Growth strategy where the rise of social awareness for energy savings is imminent, various scenarios were considered including CHP-DH (excluding waste heat recovery) versus SHP and CHP-DH (including waste heat recovery) versus SHP. To analyze the satisfaction on energy efficiency of each heating system, nationwide average field data were acquired via a survey with the help of the Korea District Heating Corporation (KDHC), and a comprehensive model for measuring sustainable value related to energy consumption, including economic (ECON), non-economic (NECON), and environmental (ENV) values were presented based on customer satisfaction (SAT). As a result of the structural equation model (SEM) and ordinary least squares (OLS) regression, variations of energy efficiencies of each heat and power delivery system are rather distinctive among different scenarios due to the performance characteristics of each system in the field. The energy savings of CHP-DH systems owned by KDHC, based on nationwide average performance, was found to be higher than the SHP system by 3.25% to 18.1%. While the effect of NECON and ENV on SAT was not significant in SHP, it was significant in CHP-DH. Based on these results, rational decisions can be made to lead the government and energy consumers to maximize energy efficiency, especially in South Korea, where the energy market heavily relies on foreign countries.
Past Performance, Organizational Aspiration, and Organizational Performance: The Moderating Effect of Environmental Jolts
Authors: Hu Chunjia , Zhang Haili , Song Michael , Liang Dapeng
Published: August 2019

Previous research has implied that past performance and organizational aspiration may have an important effect on the sustainable growth of organizational performance. Under the conditions of environmental jolts, their relationships are more complicated to discern. However, few studies have undertaken this investigation. Using data from 183 U.S. firms, this study proposes and tests a theoretical model of the relationships between past performance, organizational aspiration, and organizational performance at different environmental jolt levels. Through hierarchical regression analysis, the empirical findings suggest that low levels of environmental jolt weaken the positive relationship between organizational aspiration and organizational performance, while high levels of environmental jolt magnify the positive influence of past performance on organizational performance. Most importantly, the empirical findings reveal that at low levels of environmental jolt, past performance has no effect on organizational performance, while organizational aspiration has no effect on organizational performance when the level of environmental jolt is high. These interesting findings provide some implications for managers and enrich the theory of sustainable development.