bluuebunny/crossref_metadata_2025 huggingface dataset:
FiniteAmplitude Power Budget Equations for Acoustic Fish Abundance Estimation
Authors: Lunde Per
Published: February 2020

Finiteamplitude (nonlinear) sound propagation effects in seawater may cause measurement errors in fish and zooplankton abundance estimation and species identification for accessible echo sounder transmit electrical power levels and operating frequencies of about 100 kHz and higher. A sufficiently validated framework to quantify, control, and compensate for such errors in these applications is not available. The conventional power budget equations in fisheries acoustics are valid for smallamplitude signals only. The study aims to fill this “gap”. The conventional theory is generalized to account for finiteamplitude incident sound propagation, arbitrary electrical termination, and the range of electrical and acoustical echo sounder parameters. Equations for use in calibration and oceanic surveying are derived in terms of the backscattering cross section,, and the volume backscattering coefficient,. The “finiteamplitude terms” in these expressions can—for relevant transmit electrical power levels of relevant echo sounders—be measured in controlled tank experiments. Alternatively, they can be calculated using numerical models. The resulting equations enable estimation of finiteamplitude measurement errors in these applications; development of recommended upper limits for echo sounder power levels; controlled reduction of finiteamplitude errors in calibration and surveying; and development of correction factors for survey data already subjected to such measurement errors.
Acknowledgement to Reviewers of Laws in 2019
Authors:   Laws Editorial Office
Published: February 2020

The editorial team greatly appreciates the reviewers who have dedicated considerable time and their expertise to the journal’s rigorous editorial process over the past 12 months, regardless of whether the papers are finally published or not [...]
Structure of Fe-Mn-Al-C Steels after Gleeble Simulations and Hot-Rolling
Authors: Sozańska-Jędrasik Liwia , Mazurkiewicz Janusz , Matus Krzysztof , Borek Wojciech
Published: February 2020

In this paper, analytical results are compared for the newly developed steels, Fe-Mn-Al-C (X105) and Fe-Mn-Al-Nb-Ti-C (X98), after being hot-rolled and also after undergoing thermomechanical treatment in a Gleeble simulator. These steels have a relatively low density (~6.68 g/cm3) and a content of approx. 11% aluminum. The multistage compression of axisymmetric samples constituting a simulation of the real technological process and hot-rolling performed on a semi-industrial line were carried out using three cooling variants: in water, in air, and after isothermal heating and cooling in water. The temperature at the end of the thermomechanical treatment for all variants was 850 °C. On the basis of detailed structural studies, it was found that the main mechanism for removing the effects of the strain hardening that occurred during the four-stage compression involved the dynamic recrystallization occurring in the first and second stages, the hot formability and dynamic recovery in successive stages of deformation, and the static and/or metadynamic recrystallization that occurred at intervals between individual deformations, as well as after the last deformation during isothermal heating. Analysis of the phase composition and structure allowed us to conclude that the tested steels have an austenitic-ferritic structure with carbide precipitates. Research using scanning and transmission electron microscopy identified κ-(Fe, Mn)3AlC and M7C3 carbides in both the analyzed steels. In addition, complex carbides based on Nb and Ti were identified in X98 steel; (Ti, Nb)C carbides occurred in the entire volume of the material. Slow cooling after thermomechanical treatment influenced the formation of larger κ-carbides at the border of the austenite and ferrite grains than in the case of rapid cooling. The size and morphology of the carbides found in the examined steels was varied. Back-scattered electron diffraction studies showed that wide-angle boundaries dominated in these steels.
Evaluation Method of Relative Humidity Changes in Below-Grade Concrete Structure Space Depending on Different Waterproofing Material and Installation Method
Authors: An Ki-won , Oh Kyu-hwan , Jiang Bo , He Xingyang , Oh Sang-keun
Published: February 2020

An evaluation method for assessing the difference in the relative humidity (RH) control performance of waterproofing material is proposed. For a demonstration of this evaluation method, two waterproofing materials (urethane coating and cementitious waterproofing material) installed with different methods (positive and negative side of concrete structure respectively) are exposed to temperature conditions representing three seasonal conditions: Summer (40 °C), spring/autumn (20 °C) and winter (4 °C). Condensation level changes on the inner side of the waterproofing material installed specimen is measured, and for derive criteria for comparison, three parameters based on the average RH, intercept RH (derived from a linear regression analysis of RH measurement), and maximum relative humidity are derived for each different waterproofing material installed specimen. Based on quality specification for underground concrete structures, the demonstration evaluation establishes provisional standard criteria of below 70% RH, and all three parameters are evaluated to determine whether the tested waterproofing material/method complies to the performance requirement. Additional analysis through linear regression and cumulative probability density graphs are derived to evaluate the RH consistency and range parameters. The evaluation regime demonstrates a quantitative RH analysis method and apparatus, and a newly designed evaluation criteria is used to compare the RH control performance of positive-side installed urethane waterproofing materials and negative-side installed cementitious waterproofing material.
Experimental Evaluation of Mode II fracture Properties of Eucalyptus globulus L.
Authors: Majano-Majano Almudena , Lara-Bocanegra Antonio José , Xavier José , Morais José
Published: February 2020

Eucalyptus globulus Labill is a hardwood species of broad growth in temperate climates, which is receiving increasing interest for structural applications due to its high mechanical properties. Knowing the fracture behaviour is crucial to predict, through finite element models, the load carrying capacity of engineering designs with possibility of brittle failures such as elements with holes, notches, or certain types of joints. This behaviour can be adequately modelled on a macroscopic scale by the constitutive cohesive law. A direct identification of the cohesive law of Eucalyptus globulus L. in Mode II was performed by combining end-notched flexure (ENF) tests with digital image correlation (DIC) for radial-longitudinal crack propagation system. The critical strain energy release for this fracture mode, which represents the material toughness to crack-growth, was determined by applying the Compliance Based Beam Method (CBBM) as data reduction scheme and resulted in a mean value of 1.54 N/mm.
Feasible Use of Cathode Ray Tube Glass (CRT) and Recycled Aggregates as Unbound and Cement-Treated Granular Materials for Road Sub-Bases
Authors: Cabrera M. , Pérez P. , Rosales J. , Agrela F.
Published: February 2020

In the last 15 years, new types of display technologies have increasingly replaced cathode ray tube (CRT) screens, which has led to an increase in landfill of old discarded CRT televisions, which present a great environmental challenge throughout the world due to their high lead content. In addition, environmental awareness has led to greater use of recycled aggregates to reduce the exploitation of existing reserves. This document aims to study the feasibility of incorporating CRT glass waste with recycled aggregate (RA) in combinations for use in civil engineering, more specifically in road bases and sub-bases. For the mechanical and environmental assessment of all of the samples and materials, the following procedures have been performed: the compliance batch test of UNE-EN 12457-4:2004 for RA, CRT, and mixtures; the Percolation Test according CEN/TS 14405 for the mixtures, CRT, and RA; Modified Proctor and load capacity (the California Bearing Ratio, or CBR) in all mixtures without cement addition, and finally, compressive strength of the material treated with cement at different ages of curing. The analysis of the mechanical and environmental properties through different techniques of lixiviation was positive, showing the ability to use CRT for certain dosage percentages mixed with recycled aggregates.
The Effects of Hot-Pack Coating Materials on the Pack Rolling Process and Microstructural Characteristics during Ti-46Al-8Nb Sheet Fabrication
Authors: Huang Haohong , Liao Minle , Yu Qikai , Liu Guohuai , Wang Zhaodong
Published: February 2020

The effects of the package materials on the hot workability and stress-strain characteristics of high-Nb TiAl alloy with a nominal composition of Ti-46Al-8Nb (in at.%) were systematically studied via “sandwich structure” hot compression. TiAl sheet fabrication was conducted by hot pack rolling, and the microstructural characteristics and deformation mechanisms were investigated. Based on the analysis of compressed samples and stress-strain curves, the stainless steel/TiAl structure showed better deformation compatibility with homogeneous deformation and decreasing resistance. However, severe interfacial reactions were inevitable. Meanwhile, for the titanium alloy/TiAl structure, few interfacial reactions happened, but wavy deformation and high resistance complicated the compression process. Finally, a package structure with an outer stainless steel isolation layer and inner titanium alloy was determined for the pack rolling process. A TiAl sheet with no crack defects was obtained with 80% reduction. The pack-rolled TiAl sheet took on alternate microstructure of the grain-boundary Al-enriched ribbons and elongated lamellar colonies ribbons. The grain-boundary recrystallized α2 phase, lumpy γ phase, and massive α2/γ lamellae could be observed, which led to the scatter microstructure. The microstructural characteristics mainly resulted from the solute segregations of as-cast Ti-46Al-8Nb alloys, which triggered the local flow softening and deformation incompatibility during hot pack rolling.
Asymptotic Convergence of the Solution of a Singularly Perturbed Integro-Differential Boundary Value Problem
Authors: Zhumanazarova Assiya , Cho Young Im
Published: February 2020

In this study, the asymptotic behavior of the solutions to a boundary value problem for a third-order linear integro-differential equation with a small parameter at the two higher derivatives has been examined, under the condition that the roots of the additional characteristic equation are negative. Via the scheme of methods and algorithms pertaining to the qualitative study of singularly perturbed problems with initial jumps, a fundamental system of solutions, the Cauchy function, and the boundary functions of a homogeneous singularly perturbed differential equation are constructed. Analytical formulae for the solutions and asymptotic estimates of the singularly perturbed problem are obtained. Furthermore, a modified degenerate boundary value problem has been constructed, and it was stated that the solution of the original singularly perturbed boundary value problem tends to this modified problem’s solution.
Proteasome Inhibitors: Harnessing Proteostasis to Combat Disease
Authors: Sherman David J. , Li Jing
Published: February 2020

The proteasome is the central component of the main cellular protein degradation pathway. During the past four decades, the critical function of the proteasome in numerous physiological processes has been revealed, and proteasome activity has been linked to various human diseases. The proteasome prevents the accumulation of misfolded proteins, controls the cell cycle, and regulates the immune response, to name a few important roles for this macromolecular “machine.” As a therapeutic target, proteasome inhibitors have been approved for the treatment of multiple myeloma and mantle cell lymphoma. However, inability to sufficiently inhibit proteasome activity at tolerated doses has hampered efforts to expand the scope of proteasome inhibitor-based therapies. With emerging new modalities in myeloma, it might seem challenging to develop additional proteasome-based therapies. However, the constant development of new applications for proteasome inhibitors and deeper insights into the intricacies of protein homeostasis suggest that proteasome inhibitors might have novel therapeutic applications. Herein, we summarize the latest advances in proteasome inhibitor development and discuss the future of proteasome inhibitors and other proteasome-based therapies in combating human diseases.
The Self-Adaptation Ability of Zinc Oxide Nanoparticles Enables Reliable Cancer Treatments
Authors: Taylor Zane , Marucho Marcelo
Published: February 2020

Optimal procedures for reliable anti-cancer treatments involve the systematic delivery of zinc oxide nanoparticles, which spread through the circulatory system. The success of these procedures may largely depend on the NPs’ ability of self-adapting their physicochemical properties to overcome the different challenges facing at each stage on its way to the interior of a cancerous cell. In this article, we combine a multiscale approach, a unique nanoparticle model, and available experimental data to characterize the behavior of zinc oxide nanoparticles under different vessels rheology, pH levels, and biological environments. We investigate their ability to prevent aggregation, allow prolonged circulation time in the bloodstream, avoid clearance, conduct themselves through the capillarity system to reach damaged tissues, and selectively approach to target cancerous cells. Our results show that non-functionalized spherical zinc oxide nanoparticles with surface density N = 5.89 × 10−6 mol/m2, protonation and deprotonation rates pKa = 10.9 and pKb = −5.5, and NP size in the range of 20–50 nm are the most effective, smart anti-cancer agents for biomedical treatments.
Calcium, Vitamin D, and Health
Authors: Gracia-Marco Luis
Published: February 2020

Calcium is the main mineral in the body [...]
Role of Daily Milk Volume and Period of Lactation in Nutrient Content of Human Milk: Results from a Prospective Study
Authors: Rigourd Virginie , Lopera Isabel , Cata Florina , Benoit Guy , Jacquemet Benedicte , Lapillonne Alexandre
Published: February 2020

Most studies assessing the macronutrient content of human milk are published retrospectively using analyzers that fail to determine sodium content and do not take into account the role of volume in milk composition. We aimed to describe macronutrient content and sodium content in human milk over time, observe any associations between them, and determine the factors associated with the evolution of milk composition. A prospective, longitudinal, monocentric study was undertaken. Contents of protein, fat, and lactose of 102 milk samples from 40 mothers were determined using a human milk analyzer and that of sodium with a flame spectrophotometer. Milk volumes along with clinical data were recorded. Protein content in the fourth quartile of volume was significantly lower than that in the first three, suggesting the existence of a volume threshold for protein content at approximately 445 mL. After multivariate analysis, it was found that maternal age, average volume, and lactation period remained significantly associated with protein content, maternal age remained significantly associated with fat content, and only average volume with sodium content. In consideration of previous findings along with our data, we suggest that extra care should be taken with fortification for feeding preterm infants when the mother’s milk volume is greater than 400–450 mL.
Whey Peptides Stimulate Differentiation and Lipid Metabolism in Adipocytes and Ameliorate Lipotoxicity-Induced Insulin Resistance in Muscle Cells
Authors: D’Souza Kenneth , Mercer Angella , Mawhinney Hannah , Pulinilkunnil Thomas , Udenigwe Chibuike C. , Kienesberger Petra C.
Published: February 2020

Deregulation of lipid metabolism and insulin function in muscle and adipose tissue are hallmarks of systemic insulin resistance, which can progress to type 2 diabetes. While previous studies suggested that milk proteins influence systemic glucose homeostasis and insulin function, it remains unclear whether bioactive peptides generated from whey alter lipid metabolism and its accumulation in muscle and adipose tissue. Therefore, we incubated murine 3T3-L1 preadipocytes and C2C12 myotubes with a whey peptide mixture produced through pepsin-pancreatin digestion, mimicking peptides generated in the gut from whey protein hydrolysis, and examined its effect on indicators of lipid metabolism and insulin sensitivity. Whey peptides, particularly those derived from bovine serum albumin (BSA), promoted 3T3-L1 adipocyte differentiation and triacylglycerol (TG) accumulation in accordance with peroxisome proliferator-activated receptor γ (PPARγ) upregulation. Whey/BSA peptides also increased lipolysis and mitochondrial fat oxidation in adipocytes, which was associated with the upregulation of peroxisome proliferator-activated receptor δ (PPARδ). In C2C12 myotubes, whey but not BSA peptides ameliorated palmitate-induced insulin resistance, which was associated with reduced inflammation and diacylglycerol accumulation, and increased sequestration of fatty acids in the TG pool. Taken together, our study suggests that whey peptides generated via pepsin-pancreatin digestion profoundly alter lipid metabolism and accumulation in adipocytes and skeletal myotubes.
Ginsenoside Rg3 Induces Browning of 3T3-L1 Adipocytes by Activating AMPK Signaling
Authors: Kim Kyungtae , Nam Ki Hong , Yi Sang Ah , Park Jong Woo , Han Jeung-Whan , Lee Jaecheol
Published: February 2020

Ginsenoside Rg3, one of the major components in Panax ginseng, has been reported to possess several therapeutic effects including anti-obesity properties. However, its effect on the browning of mature white adipocytes as well as the underlying mechanism remains poorly understood. In this study, we suggested a novel role of Rg3 in the browning of mature 3T3-L1 adipocytes by upregulating browning-related gene expression. The browning effects of Rg3 on differentiated 3T3-L1 adipocytes were evaluated by analyzing browning-related markers using quantitative PCR, immunoblotting, and immunostaining. In addition, the size and sum area of lipid droplets in differentiated 3T3-L1 adipocytes were measured using Oil-Red-O staining. In mature 3T3-L1 adipocytes, Rg3 dose-dependently induced the expression of browning-related genes such as Ucp1, Prdm16, Pgc1α, Cidea, and Dio2. Moreover, Rg3 induced the expression of beige fat-specific genes (CD137 and TMEM26) and lipid metabolism-associated genes (FASN, SREBP1, and MCAD), which indicated the activation of lipid metabolism by Rg3. We also demonstrated that activation of 5’ adenosine monophosphate-activated protein kinase (AMPK) is required for Rg3-mediated up-regulation of browning gene expression. Moreover, Rg3 inhibited the accumulation of lipid droplets and reduced the droplet size in mature 3T3-L1 adipocytes. Taken together, this study identifies a novel role of Rg3 in browning of white adipocytes, as well as suggesting a potential mechanism of an anti-obesity effect of Panax ginseng.
Withania somnifera Extract Enhances Energy Expenditure via Improving Mitochondrial Function in Adipose Tissue and Skeletal Muscle
Authors: Lee Da-Hye , Ahn Jiyun , Jang Young-Jin , Seo Hyo-Deok , Ha Tae-Youl , Kim Min Jung , Huh Yang Hoon , Jung Chang Hwa
Published: February 2020

Withania somnifera (WS), commonly known as ashwagandha, possesses diverse biological functions. WS root has mainly been used as an herbal medicine to treat anxiety and was recently reported to have an anti-obesity effect, however, the mechanisms underlying its action remain to be explored. We hypothesized that WS exerts its anti-obesity effect by enhancing energy expenditure through improving the mitochondrial function of brown/beige adipocytes and skeletal muscle. Male C57BL/6J mice were fed a high-fat diet (HFD) containing 0.25% or 0.5% WS 70% ethanol extract (WSE) for 10 weeks. WSE (0.5%) supplementation significantly suppressed the increases in body weight and serum lipids, and lipid accumulation in the liver and adipose tissue induced by HFD. WSE supplementation increased oxygen consumption and enhanced mitochondrial activity in brown fat and skeletal muscle in the HFD-fed mice. In addition, it promoted browning of subcutaneous fat by increasing mitochondrial uncoupling protein 1 (UCP1) expression. Withaferin A (WFA), a major compound of WS, enhanced the differentiation of pre-adipocytes into beige adipocytes and oxygen consumption in C2C12 murine myoblasts. These results suggest that WSE ameliorates diet-induced obesity by enhancing energy expenditure via promoting mitochondrial function in adipose tissue and skeletal muscle, and WFA is a key regulator in this function.
Influences of Parental Snacking-Related Attitudes, Behaviours and Nutritional Knowledge on Young Children’s Healthy and Unhealthy Snacking: The ToyBox Study
Authors: Gibson Edward Leigh , Androutsos Odysseas , Moreno Luis , Flores-Barrantes Paloma , Socha Piotr , Iotova Violeta , Cardon Greet , De Bourdeaudhuij Ilse , Koletzko Berthold , Skripkauskaite Simona , Manios Yannis ,   on behalf of the Toybox-study Group
Published: February 2020

This study investigated parental influences on preschool children’s healthy and unhealthy snacking in relation to child obesity in a large cross-sectional multinational sample. Parents and 3–5 year-old child dyads (n = 5185) in a kindergarten-based study provided extensive sociodemographic, dietary practice and food intake data. Parental feeding practices that were derived from questionnaires were examined for associations with child healthy and unhealthy snacking in adjusted multilevel models, including child estimated energy expenditure, parental education, and nutritional knowledge. Parental healthy and unhealthy snacking was respectively associated with their children’s snacking (both p < 0.0001). Making healthy snacks available to their children was specifically associated with greater child healthy snack intake (p < 0.0001). Conversely, practices that were related to unhealthy snacking, i.e., being permissive about unhealthy snacking and acceding to child demands for unhealthy snacks, were associated with greater consumption of unhealthy snacks by children, but also less intake of healthy snacks (all p < 0.0001). Parents having more education and greater nutritional knowledge of snack food recommendations had children who ate more healthy snacks (all p < 0.0001) and fewer unhealthy snacks (p = 0.002, p < 0.0001, respectively). In the adjusted models, child obesity was not related to healthy or unhealthy snack intake in these young children. The findings support interventions that address parental practices and distinguish between healthy and unhealthy snacking to influence young children’s dietary patterns.
Saga of Superfluid Solids
Authors: Yukalov Vyacheslav I.
Published: February 2020

The article presents the state of the art and reviews the literature on the long-standing problem of the possibility for a sample to be at the same time solid and superfluid. Theoretical models, numerical simulations, and experimental results are discussed.
Ionic Conductivity and Structure of Chitosan Films Modified with Lactic Acid-Choline Chloride NADES
Authors: Smirnov Mikhail A. , Nikolaeva Alexandra L. , Vorobiov Vitaly K. , Bobrova Natalia V. , Abalov Ivan V. , Smirnov Alexander V. , Sokolova Maria P.
Published: February 2020

The natural deep eutectic solvent (NADES) based on choline chloride (ChCl) and lactic acid (LA) was used for the preparation of chitosan (CS) films by the solution casting method. The content of NADES in films was from 0 to 82 wt%. The impact of NADES on the morphology and crystalline structure of films was investigated using scanning electron microscopy as well as wide-angle and small-angle X-ray scattering. The experimental results allow to propose CS chains swelling in NADES. FTIR spectroscopy confirms the interactions between CS and NADES components via the formation of hydrogen and ion bonds. The thermal properties of the composite films were studied by simultaneous thermogravimetric and differential thermal analysis. Thermomechanical analysis demonstrated appearance of two transitions at temperatures between −23 and −5 °C and 54–102 °C depending on NADES content. It was found that electrical conductivity of film with 82 wt% of NADES reaches 1.7 mS/cm. The influence of the composition and structure of films on the charge carriers concentration and their mobility is discussed.
Preparation and Characterization of UV-Curable Acrylic Membranes Embedding Natural Antioxidants
Authors: Rajczak Ewa , Tylkowski Bartosz , Constantí Magda , Haponska Monika , Trusheva Boryana , Malucelli Giulio , Giamberini Marta
Published: February 2020

We examine the behaviour of acrylic resin-based membranes containing natural anti-oxidants, such as Galla chinensis tea powder extract (TP) and Taiwanese green propolis (TGP), in different concentrations ranging between 5 and 20 wt %. Membrane morphology was investigated by means of Environmental Scanning Electron Microscopy (ESEM), while the UV-curing reaction was monitored by Fourier-Transform Infra-red (FTIR) spectroscopy. In most cases Thermogravimetric (TG), Differential Scanning Calorimetric (DSC) and Dynamo-mechanical Thermal (DMT) analyses showed that the desirable characteristics of the UV-cured acrylic resin are not substantially altered by the presence of the organic fillers. The release kinetics of polyphenols and flavonoids, determined in water for TP-containing membranes (ETx) and in ethanol/water mixture (7:3 v/v) for TGP-containing ones (EPx), was satisfactory, reaching a plateau after 24 h. Finally, preliminary antibacterial tests against S. epidermidis were performed on the membranes with higher additive amount and gave positive results for ET-type; on the contrary, no inhibitory effect was observed for the tested EP-type membranes.
Investigation on Foamed PP/Nano-CaCO3 Composites in a Combined in-Mold Decoration and Microcellular Injection Molding Process
Authors: Yan Kui , Guo Wei , Mao Huajie , Yang Qing , Meng Zhenghua
Published: February 2020

A combined in-mold decoration and microcellular injection molding (IMD/MIM) method has been used in this paper. The foamed PP/nano-CaCO3 composites were prepared to investigate their mechanical properties, cellular structure, and surface quality. The content of nano-CaCO3 varied from 0 to 10 wt %. The results showed that nano-CaCO3 acted as a reinforcing phase and nucleating agent, which help to improve the mechanical properties of foamed composites. The cellular structure and mechanical properties were optimum when the nano-CaCO3 content was 6 wt %. In the vertical section, the cell size and density of transition layer on the film side was bigger than that on the non-film side. In the parallel section, the cell ratio of length to diameter of transition layer on the film side was smaller than that on the non-film side, and the cell tile angle was larger than that on the non-film side. With nano-CaCO3 content increasing, the surface quality showed a trend of decreasing first and then increasing.
Effect of Organic Modifier and Clay Content on Non-Isothermal Cold Crystallization and Melting Behavior of Polylactide/Organovermiculite Nanocomposites
Authors: Fernández M. Jesús , Fernández M. Dolores
Published: February 2020

In clay/polymer nanocomposites, the crystallization behavior and kinetics of the polymer can be affected by the presence of clay, its content and the degree of miscibility between the clay and the polymer matrix. The effect of two different organomodified vermiculites on the non-isothermal cold crystallization and melting behavior of polylactide (PLA) was studied by differential scanning calorimetry (DSC). In the presence of vermiculites, the cold crystallization of PLA occurred earlier, particularly for the highest content of the most miscible organovermiculite with PLA. The cold crystallinity of PLA decreased at low heating rates, notably at high organoclay loadings, and increased at high heating rates, especially at low vermiculite contents. According to the crystallization half-time, crystallization rate coefficient (CRC), and crystallization rate parameter (CRP) approaches, the cold crystallization rate of PLA increased by incorporating vermiculites, with the effect being most noteworthy for the vermiculite showing better compatibility. The Mo model was successful in describing the non-isothermal cold crystallization kinetics of the PLA/vermiculite composites. The melting behavior was affected by the heating rate and the type and content of clay. The nucleating effect of the most compatible clay resulted in the less perfect crystallites. The activation energy was evaluated using the Kissinger and Takhor methods.
Thermoresponsive Poly(ε-Caprolactone)-Poly(Ethylene/Propylene Glycol) Copolymers as Injectable Hydrogels for Cell Therapies
Authors: Brewer Kyle , Gundsambuu Batjargal , Facal Marina Paula , Barry Simon C. , Blencowe Anton
Published: February 2020

Injectable, thermoresponsive hydrogels are promising candidates for the delivery, maintenance and controlled release of adoptive cell therapies. Therefore, there is significant interest in the development of cytocompatible and biodegradable thermoresponsive hydrogels with appropriate gelling characteristics. Towards this end, a series of thermoresponsive copolymers consisting of poly(caprolactone) (PCL), poly(ethylene glycol) (PEG) and poly(propylene glycol) (PPG) segments, with various PEG:PPG ratios, were synthesised via ring-opening polymerisation (ROP) of ε-caprolactone and epoxy-functionalised PEG and PPG derivatives. The resultant PCL–PEG–PPG copolymers were characterised via proton nuclear magnetic resonance (1H NMR) spectroscopy, gel permeation chromatography (GPC) and differential scanning calorimetry (DSC). The thermoresponsive characteristics of the aqueous copolymer solutions at various concentrations was investigated using the inversion method. Whilst all of the copolymers displayed thermoresponsive properties, the copolymer with a ratio of 1:2 PEG:PPG exhibited an appropriate sol–gel transition (28 °C) at a relatively low concentration (10 wt%), and remained a gel at 37 °C. Furthermore, the copolymers were shown to be enzymatically degradable in the presence of lipases and could be used for the encapsulation of CD4+ T-cell lymphocytes. These results demonstrate that the thermoresponsive PCL–PEG–PPG hydrogels may be suitable for use as an adoptive cell therapy (ACT) delivery vehicle.
Synthesis of Polyaniline in Seawater
Authors: Yonehara Takuya , Komaba Kyoka , Goto Hiromasa
Published: February 2020

To date, polyaniline (PANI) has been synthesized in pure water. Aside from this, the application of PANI as a conducting polymer could be extended if it can be effectively synthesized in seawater, which constitutes 70% of the surface of the Earth. The production of functional plastics using natural resources without any additional purification would improve industrial production and enhance the comfort associated with our daily life. However, no examples of the effective application of seawater to PANI synthesis have been reported. Herein, PANI with an electrical conductivity of ~10−2 S/cm was synthesized in seawater as the reaction solvent. The electron spin resonance measurements confirmed the role of the polarons of PANI as charge carriers. In addition, a PANI/silk composite was prepared in seawater to produce a conducting cloth for further applications. The performance of the PANI prepared in seawater as the solvent was comparable to that of the PANI prepared in pure water. Thus, the proposed method allowed for the production of the conducting polymer via a convenient and low-cost method. This is the first study to report the usage of seawater as an abundant natural resource for synthesizing conducting polymers, promoting their wide application.
Efficient Adsorption Performance of Lithium Ion onto Cellulose Microspheres with Sulfonic Acid Groups
Authors: Xu Chenxi , Yu Tianlin , Peng Jing , Zhao Long , Li Jiuqiang , Zhai Maolin
Published: February 2020

The separation of Li+ from an aqueous solution has received much attention in recent years because of its wide application in batteries and nuclear energy. A cellulose microsphere adsorbent with sulfonic acid groups (named as CGS) was successfully prepared by the pre-irradiation-induced emulsion graft polymerization of glycidyl methacrylate onto cellulose microspheres through subsequent sulfonation and protonation. The adsorption performance of Li+ onto the CGS adsorbent is investigated in detail. The as-prepared CGS adsorbent exhibited fast adsorption kinetics and a high adsorption capacity of Li+ (16.0 mg/g) in a wide pH range from 4 to 10. The existence of K+ and Na+ was found to have the ability to affect the adsorption capacity of Li+ due to the cation-exchange adsorption mechanism, which was further confirmed by X-ray photoelectron spectroscopy (XPS). The column adsorption experiment indicated that the adsorption capacity of CGS agreed well with the batch adsorption, and a fast desorption could be obtained in 10 min. It is expected that CGS has potential usage in the adsorption separation of Li+ from an aqueous solution.
Precipitation of Pt Nanoparticles inside Ion-Track-Etched Capillaries
Authors: Yamamoto Shunya , Koshikawa Hiroshi , Taguchi Tomitsugu , Yamaki Tetsuya
Published: February 2020

Ion-track-etched capillaries containing nanoparticles of precious metals (e.g., Pt, Au, and Ag) can be applied to plasmonic absorber materials. The precipitation of homogeneous and highly dispersed precious metal nanoparticles inside capillaries represents a key process. Ion-track-etched capillaries (diameter: ~500 nm, length: ~25 μm) were created in polyimide film by 350 MeV Xe irradiation (3 × 107 ions/cm2) and chemical etching (using a sodium hypochlorite solution). The films with capillaries were immersed in an aqueous solution containing 0.1–10 mmol/L H2PtCl6 and 0.5 vol% C2H5OH, and then irradiated with a 2 MeV electron beam up to a fluence of 1.4 × 1016 e/cm2. The Pt particles inside the capillaries were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The precipitation of Pt nanoparticles and isolated aggregates inside the capillaries was confirmed by TEM. The Pt nanoparticles tended to aggregate under increasing concentrations of H2PtCl6 in the aqueous solution; meanwhile, no changes in nanoparticle size were noted under increasing electron beam fluence. The results suggest that the proposed method can be used to form metal nanoparticles in nanosized capillaries with a high aspect ratio.
Geometric Quality Assessment of Chang’E-2 Global DEM Product
Authors: Xin Xin , Liu Bin , Di Kaichang , Yue Zongyu , Gou Sheng
Published: February 2020

The Chang’E-2 digital elevation model (DEM, named CE2TMap2015), which is the highest resolution DEM product in China, was released with global coverage of the lunar surface. A detailed geometric quality assessment of the product is desirable for wider applications by users. A novel procedure for evaluating DEM geometric quality, which investigates both the global geometric uncertainty and local gross errors, is proposed in this paper. First, the DEM was divided into regular blocks and matched with the reference DEM. Then, the characteristics of errors were investigated using the statistical information of the matched tie points. Next, the local outlier factor (LOF) algorithm was performed to locate the gross errors. In our experiment, CE2TMap2015 was evaluated using the proposed method, with SLDEM2015 as the reference DEM. The results show that there were widespread geometric inconsistencies with an area-weighted average of 183.1 m horizontally (with the standard deviation being 101.2 m) and 2.3 m vertically (with the standard deviation being 15.4 m). Gross errors were detected automatically and were excluded in the statistical analysis. The periodic errors were extracted in the frequency domain using a Fourier transform. Our research results provide instructional information for the utilization of CE2TMap2015 by world-wide users. The proposed method can be used in the assessment of other planetary DEMs.
Carbon Dynamics in the Northeastern Qinghai–Tibetan Plateau from 1990 to 2030 Using Landsat Land Use/Cover Change Data
Authors: Li Jingye , Gong Jian , Guldmann Jean-Michel , Li Shicheng , Zhu Jie
Published: February 2020

Land use/cover change (LUCC) has an important impact on the terrestrial carbon cycle. The spatial distribution of regional carbon reserves can provide the scientific basis for the management of ecosystem carbon storage and the formulation of ecological and environmental policies. This paper proposes a method combining the CA-based FLUS model and the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model to assess the temporal and spatial changes in ecosystem carbon storage due to land-use changes over 1990–2015 in the Qinghai Lake Basin (QLB). Furthermore, future ecosystem carbon storage is simulated and evaluated over 2020–2030 under three scenarios of natural growth (NG), cropland protection (CP), and ecological protection (EP). The long-term spatial variations in carbon storage in the QLB are discussed. The results show that: (1) Carbon storage in the QLB decreased at first (1990–2000) and increased later (2000–2010), with total carbon storage increasing by 1.60 Tg C (Teragram: a unit of mass equal to 1012 g). From 2010 to 2015, carbon storage displayed a downward trend, with a sharp decrease in wetlands and croplands as the main cause; (2) Under the NG scenario, carbon reserves decrease by 0.69 Tg C over 2020–2030. These reserves increase significantly by 6.77 Tg C and 7.54 Tg C under the CP and EP scenarios, respectively, thus promoting the benign development of the regional ecological environment. This study improves our understanding on the impact of land-use change on carbon storage for the QLB in the northeastern Qinghai–Tibetan Plateau (QTP).
Inference in Supervised Spectral Classifiers for On-Board Hyperspectral Imaging: An Overview
Authors: Alcolea Adrián , Paoletti Mercedes E. , Haut Juan M. , Resano Javier , Plaza Antonio
Published: February 2020

Machine learning techniques are widely used for pixel-wise classification of hyperspectral images. These methods can achieve high accuracy, but most of them are computationally intensive models. This poses a problem for their implementation in low-power and embedded systems intended for on-board processing, in which energy consumption and model size are as important as accuracy. With a focus on embedded and on-board systems (in which only the inference step is performed after an off-line training process), in this paper we provide a comprehensive overview of the inference properties of the most relevant techniques for hyperspectral image classification. For this purpose, we compare the size of the trained models and the operations required during the inference step (which are directly related to the hardware and energy requirements). Our goal is to search for appropriate trade-offs between on-board implementation (such as model size and energy consumption) and classification accuracy.
Image Similarity Metrics Suitable for Infrared Video Stabilization during Active Wildfire Monitoring: A Comparative Analysis
Authors: Valero Mario M. , Verstockt Steven , Mata Christian , Jimenez Dan , Queen Lloyd , Rios Oriol , Pastor Elsa , Planas Eulàlia
Published: February 2020

Aerial Thermal Infrared (TIR) imagery has demonstrated tremendous potential to monitor active forest fires and acquire detailed information about fire behavior. However, aerial video is usually unstable and requires inter-frame registration before further processing. Measurement of image misalignment is an essential operation for video stabilization. Misalignment can usually be estimated through image similarity, although image similarity metrics are also sensitive to other factors such as changes in the scene and lighting conditions. Therefore, this article presents a thorough analysis of image similarity measurement techniques useful for inter-frame registration in wildfire thermal video. Image similarity metrics most commonly and successfully employed in other fields were surveyed, adapted, benchmarked and compared. We investigated their response to different camera movement components as well as recording frequency and natural variations in fire, background and ambient conditions. The study was conducted in real video from six fire experimental scenarios, ranging from laboratory tests to large-scale controlled burns. Both Global and Local Sensitivity Analyses (GSA and LSA, respectively) were performed using state-of-the-art techniques. Based on the obtained results, two different similarity metrics are proposed to satisfy two different needs. A normalized version of Mutual Information is recommended as cost function during registration, whereas 2D correlation performed the best as quality control metric after registration. These results provide a sound basis for image alignment measurement and open the door to further developments in image registration, motion estimation and video stabilization for aerial monitoring of active wildland fires.
Two-Phase Object-Based Deep Learning for Multi-Temporal SAR Image Change Detection
Authors: Zhang Xinzheng , Liu Guo , Zhang Ce , Atkinson Peter M. , Tan Xiaoheng , Jian Xin , Zhou Xichuan , Li Yongming
Published: February 2020

Change detection is one of the fundamental applications of synthetic aperture radar (SAR) images. However, speckle noise presented in SAR images has a negative effect on change detection, leading to frequent false alarms in the mapping products. In this research, a novel two-phase object-based deep learning approach is proposed for multi-temporal SAR image change detection. Compared with traditional methods, the proposed approach brings two main innovations. One is to classify all pixels into three categories rather than two categories: unchanged pixels, changed pixels caused by strong speckle (false changes), and changed pixels formed by real terrain variation (real changes). The other is to group neighbouring pixels into superpixel objects such as to exploit local spatial context. Two phases are designed in the methodology: (1) Generate objects based on the simple linear iterative clustering (SLIC) algorithm, and discriminate these objects into changed and unchanged classes using fuzzy c-means (FCM) clustering and a deep PCANet. The prediction of this Phase is the set of changed and unchanged superpixels. (2) Deep learning on the pixel sets over the changed superpixels only, obtained in the first phase, to discriminate real changes from false changes. SLIC is employed again to achieve new superpixels in the second phase. Low rank and sparse decomposition are applied to these new superpixels to suppress speckle noise significantly. A further clustering step is applied to these new superpixels via FCM. A new PCANet is then trained to classify two kinds of changed superpixels to achieve the final change maps. Numerical experiments demonstrate that, compared with benchmark methods, the proposed approach can distinguish real changes from false changes effectively with significantly reduced false alarm rates, and achieve up to 99.71% change detection accuracy using multi-temporal SAR imagery.
Relationship between Light Use Efficiency and Photochemical Reflectance Index Corrected Using a BRDF Model at a Subtropical Mixed Forest
Authors: Ma Li , Wang Shaoqiang , Chen Jinghua , Chen Bin , Zhang Leiming , Ma Lixia , Amir Muhammad , Sun Leigang , Zhou Guoyi , Meng Ze
Published: February 2020

Light use efficiency (LUE) is a key indicator of vegetation photosynthesis, which provides important insights into how vegetation productivity responds to environmental conditions. The photochemical reflectance index (PRI) is based on reflectance at 531 and 570 nm, which reflects the xanthophyll cycle process of plants under different radiation conditions, and makes LUE related to plant optical characteristics. In this study, tower-based PRI and eddy covariance (EC) based LUEs were used to explore the ability of PRI to track LUE variations in a subtropical, evergreen mixed forest in South China. The results indicate that there is a stronger relationship between PRI and LUE, corrected by the bidirectional reflectance distribution function (BRDF), where R2 = 0.46 before correction and R2 = 0.60 after correction. Generally, PRI is able to capture diurnal and seasonal changes in LUE. Simultaneously, this study highlights a significant correlation between LUE and PRI, but there is also a large seasonal difference in its correlation. The correlation in winter was significantly stronger than summer. The strongest correlation is found in November (R2 = 0.91) and the weakest is in July (R2 = 0.34). Photosynthetically active radiation (PAR) had a strong influence on the LUE-PRI relationship, while vapor pressure deficit (VPD) and air temperature (Ta) had negative influences on the relationship between LUE and PRI. Terrestrial laser scanning is used to retrieve the vertical structure of forest crown. Our results show that the vegetation canopy structure (i.e., effective leaf area index, LAIe), extracted from terrestrial laser scanning (TLS) point data in subtropical mixed forests, had a weak influence on LUE. Our research suggests that environmental factors and vegetation canopy structures should be considered when using PRI to accurately estimate LUE.
Monitoring Rock Glacier Kinematics with Satellite Synthetic Aperture Radar
Authors: Strozzi Tazio , Caduff Rafael , Jones Nina , Barboux Chloé , Delaloye Reynald , Bodin Xavier , Kääb Andreas , Mätzler Eva , Schrott Lothar
Published: February 2020

Active rock glaciers represent the best visual expression of mountain permafrost that can be mapped and monitored directly using remotely sensed data. Active rock glaciers are bodies that consist of a perennially frozen ice/rock mixture and express a distinct flow-like morphology indicating downslope permafrost creep movement. Annual rates of motion have ranged from a few millimeters to several meters per year, varying within the annual cycle, from year to year, as well as at the decennial time scale. During the last decade, in situ observations in the European Alps have shown that active rock glaciers are responding almost synchronously to inter-annual and decennial changes in ground temperature, suggesting that the relative changes of their kinematics are a general indicator of the evolution of mountain permafrost conditions. Here, we used satellite radar interferometry (InSAR) to monitor the rate of motion of various active rock glaciers in the Swiss Alps, Qeqertarsuaq (Western Greenland), and the semiarid Andes of South America. Velocity time series computed with Sentinel-1 SAR images, regularly acquired since 2014, every six days over Europe and Greenland and every 12 days over the Andes, show annual fluctuations, with higher velocities at the end of the summer. A JERS-1 image pair of 1996 and stacks of very high-resolution SAR images from TerraSAR-X and Cosmo-SkyMed from 2008 to 2017 were analyzed using InSAR and offset tracking over the Western Swiss Alps in order to extend the main observation period of our study. A quantitative assessment of the accuracy of InSAR and offset tracking was performed by comparison with in situ methods. Our results for the three different study regions demonstrate that Sentinel-1 InSAR can complement worldwide in situ measurements of active rock glacier kinematics.