bluuebunny/crossref_metadata_2025_split huggingface dataset:
Production of Human Milk Fat Substitutes by Interesterification of Tripalmitin with Ethyl Oleate Catalyzed by Candida parapsilosis Lipase/Acyltransferase
Authors: Tecelão Carla , Perrier Véronique , Dubreucq Eric , Ferreira‐Dias Suzana 
Published: June 2019

AbstractIn human milk fat, the saturated fatty acids, namely palmitic acid, are located at the sn‐2 position of triacylglycerols (TAG) while unsaturated fatty acids (e.g. oleic acid) are esterified at position sn‐1,3. Thus, sn‐1,3‐dioleoyl‐2‐palmitoylglycerol (OPO) is the target TAG to be used as human milk fat substitutes (HMFS) in infant formulas. In this study, the noncommercial recombinant lipase/acyltransferase from Candida parapsilosis (CpLIP2) was immobilized in Accurel MP1000, and used as a biocatalyst for the interesterification of tripalmitin with ethyl oleate in a solvent‐free medium, to obtain structured lipids used as HMFS. Different molar ratios (MR) of ethyl oleate to tripalmitin (2:1–8:1) were used. After 4 h reaction at 60°C, about 30 mol% of oleic acid incorporation was already observed for all tested MR. An apparent equilibrium was reached after 8–24 h, with 32–51 mol% final incorporation, increasing with the MR. The incorporation of oleic acid into TAG was compared with the maximum predicted values when a random or a sn‐1,3‐regioselective biocatalyst was used. The obtained values are consistent with the maximum incorporation expected for a sn‐1,3‐regioselective enzyme. In fact, the amount of oleic acid at position sn‐2 was approximately 15% for all the MR tested, which is explained by the acyl migration phenomenon. CpLIP2 exhibited higher activity than most commercial immobilized lipases (e.g. faster reaction in solvent‐free media, low enzyme load, and low MR needed), and showed a recognized sn‐1,3 regioselective behavior.
Improving the ductility of polylactic acid parts produced by fused deposition modeling through polyhydroxyalkanoate additions
Authors: Kaygusuz Burçin , Özerinç Sezer 
Published: June 2019

ABSTRACTPolylactic acid (PLA) is one of the most commonly used materials for fused deposition modeling (FDM) due to its low cost, biocompatibility, and desirable printing characteristics. However, its low ductility is a major disadvantage for engineering applications where high damage tolerance is needed. This study investigates the feasibility of polyhydroxyalkanoate (PHA) additions to PLA for improving the ductility of parts produced by FDM. Thermal and mechanical behavior of PLA/PHA specimens containing 12 wt % PHA is investigated for a range of printing nozzle temperatures. All PLA/PHA specimens exhibit amorphous PLA phase with semicrystalline PHA and possess outstanding ductility exceeding 160% for nozzle temperatures in the range of 200 °C–240 °C. Lower and higher nozzle temperatures result in low ductility, similar to that of pure PLA. Overall, PLA/PHA is a very promising polymer blend for FDM processes, providing a combination of sufficient strength with excellent damage tolerance. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48154.
Tuning gradient microstructures in immiscible polymer blends by viscosity ratio
Authors: Pan Dan , Hufenus Rudolf , Qin Zongyi , Chen Long , Gooneie Ali 
Published: June 2019

ABSTRACTBioinspired gradient microstructures provide an attractive template for functional materials with tailored properties. In this study, filaments with gradient microstructures are developed by melt‐spinning of immiscible polymer blends. The distribution of the gradient morphology is shown to be controlled by the viscosity ratio of polymers as well as the geometry of the capillary die. Distinct microstructure gradients with long thin fibrils near the surface region and short large droplets near the center region of the filament, as well as the inverse pattern, are formed in systems with different viscosity ratios. The shear flow field in the capillary can elucidate the formation mechanisms of gradient morphologies during processing. The results demonstrate how the features of a gradient microstructure can be tailored by the design of capillary geometry and processing conditions. The viscosity ratio is then introduced as an adjusting tool to control the gradient morphology in a given processing setup. In consequence, this study provides novel design routes for achieving gradient morphologies in immiscible polymers. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 48165.
Conductive and flexible multi‐walled carbon nanotube/polydimethylsiloxane composites made with naphthalene/toluene mixture
Authors: Mulembo Titus , Nagai Gakuji , Tamagawa Hirohisa , Nitta Takahiro , Sasaki Minoru 
Published: June 2019

ABSTRACTConventional conductive materials face challenges when utilizing them for flexible and wearable electronics and soft robotics. Carbon nanotube/polydimethylsiloxane (CNT/PDMS) composites are a promising alternative to the conventional hard conductors because they are light and can realize large deformation. To date, well dispersion of CNTs into PDMS to increase conductivity while maintaining flexibility remains challenging. We aimed at developing highly electrically conductive and flexible multi‐walled carbon nanotube/PDMS (MWCNT/PDMS) composites. To this end, we proposed a method to enhance the dispersion of MWCNTs into PDMS using naphthalene and toluene. Our results showed that the addition of naphthalene and toluene into the composites improved dispersion of the MWCNTs and increased the direct current (DC) electrical conductivity. We also found that the morphology of primary aggregates of the MWCNTs influenced the DC electrical conductivity of the composites. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48167.
Exploring the filler–polymer interaction and solvent transport behavior of nanocomposites derived from reduced graphene oxide and polychloroprene rubber
Authors: Maya M. G. , Abraham Jiji , George Soney C. , Thomas Sabu 
Published: June 2019

ABSTRACTAliphatic solvent resistance of polychloroprene rubber (CR) reinforced reduced graphene oxide (RGO) nanocomposites were explored in the temperature range of 30–50 °C using hexane, heptane, and octane. Microstructure‐assisted solvent resistant property is evident from transmission electron microscopy images of fabricated composites. Different transport parameters such as diffusion, permeation, and sorption constants were moderate while increasing RGO content. Diffusion mechanism was explained based on the permeating molecule and is found to be close to Fickian mechanism except for heptane. Evaluation of kinetic and thermodynamic parameters shows the ability of nanoreinforcement to alter thermodynamic characteristics and rate constant values. The extent of reinforcement was also evaluated by Kraus equation. From swelling studies, molecular mass between crosslinks was evaluated using Flory–Rehner equation and compared these values with theoretical predictions such as phantom and affine models to analyze the deformation and mobility of the network during swelling. Temperature plays a significant role in the transport of organic solvent through CR/RGO nanocomposites. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48168.
Sea Change Tai Timu Tai Pari: addressing catchment and marine issues in an integrated marine spatial planning process
Authors: Peart Raewyn 
Published: June 2019

Abstract

Marine spatial planning (MSP) has increasingly been applied around the world to better manage the pressures and conflicts arising from human use of the sea. More recently it has been conceived as an approach to implement an ecosystem‐based management approach to the marine environment.
New Zealand was a late adopter of MSP, commencing its first MSP process in 2013 for the Hauraki Gulf (Sea Change Tai Timu Tai Pari), and completing the plan in late 2016.
The planning process drew on international experience in MSP and collaborative processes but was adapted considerably to take account of the local context. Most particularly, the plan reflected concerns about the ecological decline of the Hauraki Gulf as well the strong and growing role of Māori in natural resource management in New Zealand.
The Sea Change Tai Timu Tai Pari project was experimental and represents an innovation in MSP practice in a number of respects including: establishing a co‐governance structure for the project; tasking a group of Māori tribal and stakeholder representatives with producing the plan on a collaborative basis; addressing both catchment and marine issues and sectors in an integrated manner; and integrating indigenous knowledge with science.
A number of valuable lessons from marine planning can be drawn from this project, including: MSP can support ecosystem‐based management; collaborative processes can be powerful in achieving shared outcomes for the community and can create a rich learning environment for scientists; indigenous knowledge can strengthen planning processes by providing more holistic knowledge; and scientists within a MSP project can help frame the planning process and act as a conduit between the scientific and layperson communities.
Novel ketoprofen–antioxidants mutual codrugs as safer nonsteroidal anti‐inflammatory drugs: Synthesis, kinetic and pharmacological evaluation
Authors: Sehajpal Shikha , Prasad Deo Nandan , Singh Rajesh K. 
Published: June 2019

AbstractKetoprofen belongs to one of the most common nonsteroidal anti‐inflammatory drugs (NSAIDs) but its clinical usefulness has been restricted due to the high incidence of gastrointestinal complications. The release of reactive oxygen species (ROS) in NSAIDs therapy plays a major role in causing gastric complications. Antioxidants not only prevent gastric ulceration and lipid peroxidation but also preserve glutathione‐type peroxidase (GPO) activity. Therefore, the present study investigates the utility of combining anti‐inflammatory and antioxidant properties of two different compounds in a single molecule to form a series of 16 ketoprofen–antioxidant mutual codrugs. The free carboxylic group, which is believed to be one of the reasons for gastric toxicity of ketoprofen, was masked temporarily by simple and double esterification with alcoholic/phenolic–OH of natural antioxidants. In simple esterification, ketoprofen is directly linked to natural antioxidants (IIa–h) in the hope to obtain drugs free of gastric side effects. In an attempt to improve the in vivo lability, as well as gastric side effects, the double ester codrugs, that is, ketoprofen–antioxidant through the glycolic acid spacer (–CH2COO; IIIa–h), have also been designed and synthesized. The synthesized codrugs were characterized by IR, 1H NMR, 13C NMR, mass spectroscopy and elemental analysis. The in vitro hydrolysis studies showed the lowest hydrolysis (highest stability) in acidic pH 1.2, whereas moderate hydrolysis was seen at pH 7.4 and significant hydrolysis in 80% human blood plasma, as indicated by their t1/2. The pharmacological evaluation results indicate that these ketoprofen–antioxidant mutual codrugs showed the retention of anti‐inflammatory and analgesic activity with a significant reduction in the ulcer index.
Radial basis neural tree model for improving waste recovery process in a paper industry
Authors: Chakraborty Tanujit , Chattopadhyay Swarup , Chakraborty Ashis Kumar 
Published: June 2019

AbstractIn this article, we propose a novel hybridization of regression trees (RTs) and radial basis function networks, namely, radial basis neural tree model, for waste recovery process (WRP) improvement in a paper industry. As a by‐product of the paper manufacturing process, a lot of waste along with valuable fibers and fillers come out from the paper machine. The WRP involves separating the unwanted materials from the valuable ones so that the recovered fibers and fillers can be further reused in the production process. This job is done by fiber‐filler recovery equipment (FFRE). The efficiency of FFRE depends on several crucial process parameters, and monitoring them is a difficult proposition. The proposed model can be useful to find the essential parameters from the set of available data and to perform prediction task to improve WRP efficiency. An idea of parameter optimization along with regularity conditions for the universal consistency of the proposed model is given. The proposed model has the advantages of easy interpretability and excellent performance when applied to the FFRE efficiency improvement problem. Improved waste recovery will help the industry to become environmentally friendly with less ecological damage apart from being cost‐effective.
Meta-analysis of routine calcium/vitamin D3 supplementationversusserum calcium level-based strategy to prevent postoperative hypocalcaemia after thyroidectomy
Authors: Sanabria A , Rojas A , Arevalo J 
Published: June 2019

AbstractBackgroundThe aim was to assess the effectiveness of routine administration of calcium +/– vitamin D3 compared with a serum calcium level-based strategy to prevent symptomatic hypocalcaemia after thyroidectomy.MethodsRCTs comparing routine supplementation of calcium +/– vitamin D3 with treatment based on serum calcium levels measured after total thyroidectomy, published between 1980 and 2017, were identified in MEDLINE, Embase, LILACS and Google Scholar databases. Risk of bias was evaluated using the Cochrane Collaboration tool. Risk differences were calculated by random-effects meta-analysis. Meta-regression and cumulative meta-analysis were used to explore the best therapeutic approach.ResultsFifteen studies with 3037 patients were included, and seven treatment comparisons were made. Routine supplementation with calcium + vitamin D3 offered a lower risk of symptomatic (risk difference (RD) –0·25, 95 per cent c.i. –0·32 to –0·18) and biochemical (RD –0·24, –0·31 to –0·17) hypocalcaemia than treatment based on measurement of calcium levels. The number needed to treat was 4 (95 per cent c.i. 3 to 6) for symptomatic hypocalcaemia. No publication bias was found; although heterogeneity was high for some comparisons, sensitivity analysis did not change the main results.ConclusionRoutine postoperative administration of calcium + vitamin D3 is effective in decreasing the rate of symptomatic and biochemical hypocalcaemia.
Electrical storm in an acquired short QT syndrome successfully treated with quinidine
Authors: Spartalis Michael , Livanis Efthimios , Spartalis Eleftherios , Tsoutsinos Alexandros 
Published: June 2019

AbstractShort QT syndrome (SQTS) is a malignant heart disorder defined by the presence of ventricular arrhythmias causing syncope and sudden cardiac arrest. The prevalence in the pediatric population is 0.05%. Quinidine is an established agent for pharmacological prophylaxis in SQTS patients, but can also terminate an electrical storm.
Oxygen Reduction Reaction Activity of Mesostructured Cobalt‐Based Metal Oxides Studied with the Cavity‐Microelectrode Technique
Authors: Behnken Julian , Yu Mingquan , Deng Xiaohui , Tüysüz Harun , Harms Corinna , Dyck Alexander , Wittstock Gunther 
Published: June 2019

AbstractCobalt oxides are known as abundant and stable catalysts for the oxygen reduction reaction (ORR) in an alkaline environment. Here, the ORR activity of Co3O4 and mixed metal oxides NiCo2O4 and CuCo2O4 was studied. Synthesis by using the nanocasting procedure resulted in a mesostructured spinel phase with uniform morphology and high surface area. However, the evaluation of the specific activity of this material class is often hampered by limitations in determining the real surface area. The cavity‐microelectrode technique did not require the addition of any additives to the catalytic material. Thus, measuring the double layer capacitance was used to assess the surface area. This approach showed comparable and reliable values for all samples and different cavity depths. Furthermore, the in situ derived surface area enabled the determination of the specific ORR activity, which is more accurate than utilizing the geometric and nitrogen absorption derived surface area. Although the activity of Co3O4 was rather low, the presence of Ni2+ and Cu2+ in the mixed metal oxides led to a substantial activity enhancement, possibly by providing additional active sites.
Enhancing the Variability of [Ge9] Cluster Chemistry through Phosphine Functionalization
Authors: Wallach Christoph , Geitner Felix S. , Klein Wilhelm , Fässler Thomas F. 
Published: June 2019

AbstractThe synthetic approach towards molecules that contain Ge atoms with oxidation state 0, and which are exclusively connected to other Ge atoms, is explored by using anionic clusters extracted from binary solids. Besides providing a novel variable method for the introduction of alkenyl moieties to [Ge9] cluster compounds, this work expands the spectrum of mixed‐functionalized [Ge9] cluster anions, which are suitable for the straightforward synthesis of zwitterionic compounds upon coordination to metal cations. In detail, the synthesis of a series of mixed‐functionalized [Ge9] clusters is reported, including [Ge9{Si(TMS)3}3PRRI] (R=tBu, RI=(CH2)3CH=CH2; 2) and [Ge9{Si(TMS)3}2PRRI]− (R and RI: alkyl, alkenyl, aryl, aminoalkyl; 3 a to 11 a, TMS: (trimethyl)silyl). In 2 and 3 a, pentenyl functionalization of the [Ge9] clusters was achieved by reaction of the novel chlorophosphine tBu{(CH2)3CH=CH2}PCl (1) with silylated [Ge9] clusters. Furthermore, the reactivity of the cluster anions 3 a to 11 a towards NHCDippMCl (NHCDipp=1,3‐di(2,6‐diisopropylphenyl)imidazolylidine; M=Cu, Ag) showed a dependency on the steric demand of the phosphine either zwitterions (3‐MNHCDipp to 7‐MNHCDipp) featuring P–M interactions are formed, or Ge–M coordination (8‐MNHCDipp to 11‐MNHCDipp) occurs. For M=Ag, the formation of zwitterionic complexes was unequivocally proven by NMR investigations showing 1J(31P‐107Ag/109Ag) spin‐spin coupling.
Multi‐tier authentication schemes for fog computing: Architecture, security perspective, and challenges
Authors: Manzoor Awais , Shah Munam Ali , Khattak Hasan Ali , Din Ikram Ud , Khan Muhammad Khurram 
Published: June 2019

SummaryFog computing has revolutionized the computing domain by enabling resource sharing, such as online storage, and providing applications and software as services in near vicinity to the edge nodes through the Internet. Small‐ to large‐sized companies, like Amazon, Google, Facebook, Twitter, and LinkedIn, have started switching to fog‐computing–enabled infrastructures. Fog computing being distributed in nature and in near vicinity gives rises to security and privacy issues. Although mostly now a days, user identification is adopted via single sign‐in process, such as simple password‐based authentications, which is not a secure process. Several multi‐tier authentication techniques are proposed to overcome single sign‐in process limitations. In this article, we go through state‐of‐the‐art schemes proposed over the period of 2011‐2018 for multi‐tier authentication, their weaknesses and security issues, and finally their solutions for fog‐computing environment. We performed the comparison of available multi‐tier authentication techniques based on three factors, ie, level of security, cost of deployment, and usability. Multi‐tier authentication techniques are classified into categories in accordance with the aspects that are concerned with the authentication process. We are optimistic that this work will provide useful information to the researchers about the architectures of fog enabled systems and the underlying authentication models in a consolidated form.
Acacia dealbata invasion in Chile: Surprises from climatic niche and species distribution models
Authors: Langdon Bárbara , Pauchard Aníbal , Bustamante Ramiro O. 
Published: June 2019

AbstractAimTree invasions are a threat to biodiversity conservation, and although it is hard to predict the future spread of invasive tree species, there are tools available which could allow some estimations. The magnitude of spatial spread (a proxy of invasiveness) can be predicted from species climatic requirement (climatic niche) and can be represented by species distribution models (SDMs). We aimed to assess whether Acacia dealbata conserves its niche in the new environment of south‐central Chile, and also, to estimate the invasive stage of the species.LocationSouth‐central area of Chile, between the O'Higgins (34°0″0′S) and Aysen Regions (47°0″0′S).MethodsWe used a combination of global, native, and regional data to improve the estimation of the potential distribution of A. dealbata, which has been considered one of the most invasive species of the genus, being registered in at least 34 countries in all the Continents.ResultsOur results show that A. dealbata does not conserve its niche in the study area, invading areas with climatic conditions different from those of the native range. It is also not at equilibrium with the environment. According to the global versus regional SDM comparisons, populations present in south‐central Chile present different invasion stages. There are some stable populations, but there are other populations colonizing new areas, occupying unsuitable habitats and some of them are adapting to new climatic conditions. Climatic factors, such as precipitation seasonality, could be acting behind the expansion to new environments, and biotic factors or dispersal limitations could be preventing the species to colonize suitable areas.Main conclusionsThe invasion process of A. dealbata is far from stabilizing, and management options should focus on prevention, avoiding, for example, the introduction of the species to Patagonia where the species has not spread yet. More research is needed to complement our results and enhance the development of effective management strategies.
Population structure and the evolution of Homo sapiens in Africa
Authors: Klein Richard G. 
Published: June 2019

AbstractIt has been proposed that a multiregional model could describe how Homo sapiens evolved in Africa beginning 300,000 years ago. Multiregionalism would require enduring morphological or behavioral differences among African regions and morphological or behavioral continuity within each. African fossils, archeology, and genetics do not comply with either requirement and are unlikely to, because climatic change periodically disrupted continuity and reshuffled populations. As an alternative to multiregionalism, I suggest that reshuffling produced novel gene constellations, including one in which the additive or cumulative effect of newly associated genes enhanced cognitive or communicative potential. Eventual fixation of such a constellation in the lineage leading to modern H. sapiens would explain the abrupt appearance of the African Later Stone Age 50–45 thousand years ago, its nearly simultaneous expansion to Eurasia in the form of the Upper Paleolithic, and the ability of fully modern Upper Paleolithic people to swamp or replace non‐modern Eurasians.