bluuebunny/crossref_metadata_2025 huggingface dataset:
An Estimation of Sensitive Attribute Applying Geometric Distribution under Probability Proportional to Size Sampling
Authors: Lee Gi-Sung , Hong Ki-Hak , Son Chang-Kyoon
Published: November 2019

In this paper, we extended Yennum et al.’s model, in which geometric distribution is used as a randomization device for a population that consists of different-sized clusters, and clusters are obtained by probability proportional to size (PPS) sampling. Estimators of a sensitive parameter, their variances, and their variance estimators are derived under PPS sampling and equal probability two-stage sampling, respectively. We also applied these sampling schemes to Yennum et al.’s generalized model. Numerical studies were carried out to compare the efficiencies of the proposed sampling methods for each case of Yennum et al.’s model and Yennum et al.’s generalized model.
Finding Determinant Forms of Certain Hybrid Sheffer Sequences
Authors: Alansari Monairah , Riyasat Mumtaz , Khan Subuhi , Kazmi Kaleem Raza
Published: November 2019

In this article, the integral transform is used to introduce a new family of extended hybrid Sheffer sequences via generating functions and operational rules. The determinant forms and other properties of these sequences are established using a matrix approach. The corresponding results for the extended hybrid Appell sequences are also obtained. Certain examples in terms of the members of the extended hybrid Sheffer and Appell sequences are framed. By employing operational rules, the identities involving the Lah, Stirling and Pascal matrices are derived for the aforementioned sequences.
Transition-Age Young Adults with Cerebral Palsy: Level of Participation and the Influencing Factors
Authors: Rožkalne Zane , Mukāns Maksims , Vētra Anita
Published: November 2019

Background and Objectives: The aim of this study was to identify the level of participation in the context of the developmental transition from adolescence to adult life for young adults with cerebral palsy (CP) and the factors that had an influence on participation. Materials and Methods: Eighty-one young adults (16–21 years old) with CP and with normal or slightly decreased cognitive function participated in this study. Assessments were made using the Rotterdam Transition Profile (RTP) and the WHO Disability Assessment Schedule 2.0 (WHODAS 2.0). In the binary regression model, levels of participation (RTP scores) were set as dependents and the level of disability (WHODAS 2.0 scores), age, and level of gross motor function were set as independent variables. Results: In the age group <18 years, in three out of seven RTP domains, less than 10% of participants were in phase 2 (experimenting and orientating toward the future), i.e., finance—7%, housing—7%, sexuality—4%. In the age group ≥18 years, 21% (education and employment), 56% (intimate relationships), and 59% (sexuality) of the participants were in phase 0 (no experience). Higher scores in WHODAS 2.0 domains showed positive associations with RTP domains, i.e., cognition with social activities, mobility with transportation, self-care with sexuality and transportation, and life activities with transportation. Age was positively associated with education and employment, finance, housing, and sexuality. Low motor function according to the Gross Motor Function Classification System (GMFCS) had negative associations with autonomy in social activities, sexuality, and transportation. Conclusions: Young adults with cerebral palsy showed low levels of autonomy in all domains of participation. When addressing a person’s improvement in terms of their participation, the promotion of abilities in cognition, mobility, self-care, and life activities should be attempted. Age and gross motor function influenced autonomy in participation, but not in all domains.
Translation, Cultural, and Clinical Validation of the Lithuanian Version of the Spiritual Needs Questionnaire among Hospitalized Cancer Patients
Authors: Riklikienė Olga , Spirgienė Lina , Kaselienė Snieguolė , Luneckaitė Žydrūnė , Tomkevičiūtė Jūratė , Büssing Arndt
Published: November 2019

Background and Objectives: The aim was to translate and validate the spiritual needs questionnaire for its use in the Lithuanian context. Materials and Methods: A descriptive, cross-sectional survey design was applied. Structural individual interview method (face-to-face) was employed to collect data on spiritual needs of cancer patients. Responses were obtained from 247 patients hospitalized in nursing and supportive treatment units at public hospitals. Data were analyzed using the Statistical Package for Social Sciences (IBM SPSS Statistics) version 22.0. To assess the psychometric properties of the scale, Cronbach’s alpha, split half test, average inter-item, and item-total correlations were calculated for internal consistency. Exploratory factor analysis was used to confirm the construct validity of the translated version of instrument. Results: Lithuanian version of The Spiritual Needs Questionnaire (27 items) had a good internal consistency (Cronbach’s alpha = 0.94). The existential and connectedness with family needs factor had the lowest Cronbach’s alpha (0.71) in relation to other factors: Religious needs (0.93), giving/generativity and forgiveness needs (0.88), and inner peace needs (0.74). Split-half test showed strong relationship between the both halves of the test. The item difficulty (1.47 (mean value)/3) was 0.49; while all values were in acceptable range from 0.20 to 0.80. Item-total correlations were inspected for the items in each of the four SpNQ-27 factors. Conclusions: The Lithuanian version of Spiritual needs questionnaire demonstrated adequate psychometric properties of the instrument. This instrument, as a screening tool and conversational model, is recommended for clinicians in health care practice to identify patients with spiritual needs.
Mechanical Properties of Some Metallic Powder Alloys and Their Contribution to the Performance of Diamond Tools Used for Cutting Granite
Authors: Rosa Luís Guerra , Anjinho Carlos A. , Amaral Pedro M. , Fernandes Jorge Cruz
Published: November 2019

This work examined some pre-alloyed cobalt-, iron-, and copper-based powder binder systems—such as those launched commercially under the brand names of Cobalite and Next—in terms of their as-sintered physical-mechanical properties, namely, apparent density, Young´s modulus, yield strength, rupture strength, rupture strain, toughness modulus, and Vickers hardness. These types of sintered products are traditionally used in the fabrication of diamond impregnated tools for cutting granite stones. The following powder binder systems were evaluated: Cobalite HDR pre-alloyed powder, Next 300 pre-alloyed powder, and four other mixtures of these with Cu and Fe powders: Cobalite HDR + 20 wt% Cu; Cobalite HDR + 20 wt% Fe; Next 300 + 20 wt% Cu; Next 300 + 20 wt% Fe. The evaluation methodology aimed to establish criteria for developing new diamond tools and, therefore, it included the measurement of several technological parameters directly related to the cutting performance of the tools (e.g., energy consumption measurements made exclusively in the tool drive motor, forces generated in the tool, tool consumption per unit weight of stone removed by the cutting). The results show the adequacy of the methodology for the optimisation of diamond retention capacity of these types of metal matrices and for improving the working performance of the diamond tools.
Properties of TiC and TiN Reinforced Alumina–Zirconia Composites Sintered with Spark Plasma Technique
Authors: Szutkowska Magdalena , Cygan Sławomir , Podsiadło Marcin , Laszkiewicz-Łukasik Jolanta , Cyboroń Jolanta , Kalinka Andrzej
Published: November 2019

In this paper, Al2O3–ZrO2 composites with an addition of 20 wt% TiN and 10 wt% TiC were modified. The addition of zirconia in a range from 2 to 5 wt% of the monoclinic phase and 10 wt% of Y2O3 stabilised ZrO2 affected the mechanical properties of the composites. A new type of sintering technique—the spark plasma sintering (SPS) method—within a temperature range from 1575 °C to 1675 °C, was used. Vickers hardness, apparent density, wear resistance and indentation fracture toughness KIC(HV) were evaluated at room temperature. An increase of the sintering temperature resulted in an improvement of Vickers hardness and an increase of the fracture toughness of the tested composites. The tribological properties of the samples were tested using the ball-on-disc method. The friction coefficient was in a range from 0.31 to 0.55, depending on the sintering temperature. An enhancement of the specific wear rate was dependent on the sintering temperature. The mechanical properties of the samples sintered by pressureless sintering (PS) were compared. X-ray diffraction patterns were presented in order to determine the phase composition. SEM microstructure of the tested composites sintered at different temperatures was observed.
Metallothermic Al-Sc Co-Reduction by Vacuum Induction Melting Using Ca
Authors: Brinkmann Frederic , Mazurek Carolin , Friedrich Bernd
Published: November 2019

Due to its enhancing properties in high-tech material applications, the rare earth element Scandium (Sc) is continuously gaining interest from researchers and material developers. The aim of this research is to establish an energy and resource efficient process scheme for an in situ extraction of Al-Sc master alloys, which offers usable products for the metallurgical industry. An AlSc20 alloy is targeted with an oxyfluoridic slag as a usable by-product. The thermochemical baseline is presented by modelling using the software tool FactSage; the experimental metal extraction is conducted in a vacuum induction furnace with various parameters, whereas kinetic aspects are investigated by thermogravimetric analysis. The Sc-containing products are analyzed by ICP-OES/IC concerning their chemical composition. Optimum parameters are derived from a statistical evaluation of the Sc content in the obtained slag phase. The material obtained was high in Ta due to the crucible material and remarkably low in Al and F; a comparison between the modelled and the obtained phases indicates kinetic effects inhibiting the accomplishment of equilibrium conditions. The formation of a Sc-rich Al-Sc phase (32.5 wt.-% Sc) is detected by SEM-EDS analysis of the metal phase. An in situ extraction of Al from Ca with subsequent metallothermic reduction of ScF 3 as a process controlling mechanism is presumed.
Effects of Aging and Methionine Restriction on Rat Kidney Metabolome
Authors: Pradas Irene , Jové Mariona , Cabré Rosanna , Ayala Victoria , Mota-Martorell Natalia , Pamplona Reinald
Published: November 2019

Methionine restriction (MetR) in animal models extends maximum longevity and seems to promote renoprotection by attenuating kidney injury. MetR has also been proven to affect several metabolic pathways including lipid metabolism. However, there is a lack of studies about the effect of MetR at old age on the kidney metabolome. In view of this, a mass spectrometry-based high-throughput metabolomic and lipidomic profiling was undertaken of renal cortex samples of three groups of male rats—An 8-month-old Adult group, a 26-month-old Aged group, and a MetR group that also comprised of 26-month-old rats but were subjected to an 80% MetR diet for 7 weeks. Additionally, markers of mitochondrial stress and protein oxidative damage were analyzed by mass spectrometry. Our results showed minor changes during aging in the renal cortex metabolome, with less than 59 differential metabolites between the Adult and Aged groups, which represents about 4% of changes in the kidney metabolome. Among the compounds identified are glycerolipids and lipid species derived from arachidonic acid metabolism. MetR at old age preferentially induces lipid changes affecting glycerophospholipids, docosanoids, and eicosanoids. No significant differences were observed between the experimental groups in the markers of mitochondrial stress and tissue protein damage. More than rejuvenation, MetR seems to induce a metabolic reprogramming.
Dynamics Behaviors of Droplet on Hydrophobic Surfaces Driven by Electric Field
Authors: Liu Jie , Liu Sheng
Published: November 2019

Droplet microfluidic technology achieves precise manipulation of droplet behaviors by designing and controlling the flow and interaction of various incompatible fluids. The electric field provides a non-contact, pollution-free, designable and promising method for droplet microfluidics. Since the droplet behaviors in many industrial and biological applications occur on the contact surface and the properties of droplets and the surrounding environment are not consistent, it is essential to understand fundamentally the sessile droplet motion and deformation under various conditions. This paper reports a technique using the pin-plate electrode to generate non-uniform dielectrophoresis (DEP) force to control sessile droplets on hydrophobic surfaces. The electrohydrodynamics phenomena of the droplet motion and deformation are simulated using the phase-field method. It is found that the droplet moves along the substrate surface to the direction of higher electric field strength, and is accompanied with a certain offset displacement. In addition, the effect of pin electric potentials, surface contact angles and droplet volumes on the droplet motion and deformation are also studied and compared. The results show that higher potentials, more hydrophobic surfaces and larger droplet volumes exhibit greater droplet horizontal displacement and offset displacement. But for the droplet vertical displacement, it is found that during the first revert process, the release of the surface tension can make the droplet with low potentials, small contact angles or small droplet volumes span from negative to positive. These results will be helpful for future operations encountered in sessile droplets under non-uniform electric fields towards the droplet microfluidics applications.
Electrical Performance and Bias-Stress Stability of Amorphous InGaZnO Thin-Film Transistors with Buried-Channel Layers
Authors: Zhang Ying , Xie Haiting , Dong Chengyuan
Published: November 2019

To improve the electrical performance and bias-stress stability of amorphous InGaZnO thin-film transistors (a-IGZO TFTs), we fabricated and characterized buried-channel devices with multiple-stacked channel layers, i.e., a nitrogen-doped a-IGZO film (front-channel layer), a conventional a-IGZO film (buried-channel layer), and a nitrogen-doped a-IGZO film (back-channel layer). The larger field-effect mobility (5.8 cm2V−1s−1), the smaller subthreshold swing value (0.8 V/dec, and the better stability (smaller threshold voltage shifts during bias-stress and light illumination tests) were obtained for the buried-channel device relative to the conventional a-IGZO TFT. The specially designed channel-layer structure resulted in multiple conduction channels and hence large field-effect mobility. The in situ nitrogen-doping caused reductions in both the front-channel interface trap density and the density of deep states in the bulk channel layers, leading to a small subthreshold swing value. The better stability properties may be related to both the reduced trap states by nitrogen-doping and the passivation effect of the nitrogen-doped a-IGZO films at the device back channels.
Nataliakulikite, Ca4Ti2(Fe3+,Fe2+)(Si,Fe3+,Al)O11, a New Perovskite-Supergroup Mineral from Hatrurim Basin, Negev Desert, Israel
Authors: Sharygin Victor V. , Yakovlev Grigory A. , Wirth Richard , Seryotkin Yurii V. , Sokol Ellina V. , Nigmatulina Elena N. , Karmanov Nikolai S. , Pautov Leonid A.
Published: November 2019

Nataliakulikite, Ca4Ti2(Fe3+,Fe2+)(Si,Fe3+,Al)O11, is a mineral intermediate between perovskite CaTiO3 and brownmillerite Ca2(Fe,Al)2O5. It was discovered as a minor mineral in a high-temperature pyrometamorphic larnite-gehlenite rock at the Nahal Morag Canyon of the Hatrurim Basin, Israel. Nataliakulikite is associated with larnite, flamite, gehlenite, magnesioferrite, Fe3+-rich perovskite, fluorapatite, barite, Hashemite, and retrograde phases (afwillite, hillebrandite, portlandite, calcite, ettringite, hydrogarnet, and other hydrated Ca-silicates). The mineral forms brown subhedral or prismatic grains (up to 20 µm) and their intergrowths (up to 50 μm). Its empirical formula (n = 47) is (Ca3.992Sr0.014U0.004)(Ti1.933Zr0.030Nb0.002) (Fe3+0.610Fe2+0.405Cr0.005Mn0.005)(Si0.447Fe3+0.337Al0.216)O11 and shows Si predominance in tetrahedral site. The unit-cell parameters (HRTEM data) and space group are: a = 5.254, b = 30.302, c = 5.488 Å, V = 873.7 Å3, Pnma, Z = 4. These dimensions and Electron backscatter diffraction (EBSD) data strongly support the structural identity between nataliakulikite and synthetic Ca4Ti2Fe3+2O11 (2CaTiO3∙Ca2Fe3+2O5), an intermediate compound in the system CaTiO3-Ca2Fe3+2O5. In general, this mineral is a Si-Fe2+-rich natural analog of synthetic Ca4Ti2Fe3+2O11. The X-ray powder diffraction data (CuKα -radiation), calculated from unit-cell dimensions, show the strongest lines {d [Å], (Icalc)} at: 2.681(100), 1.898(30), 2.627(26), 2.744(23), 1.894(22), 15.151(19), 1.572(14), 3.795(8). The calculated density is 4.006 g/cm3. The crystal structure of nataliakulikite has not been refined because of small sizes of grains. The Raman spectrum shows strong bands at 128, 223, 274, 562, and 790 cm−1. Nataliakulikite from the Hatrurim Basin crystallized under the conditions of combustion metamorphism at high temperatures (1160–1200 °C) and low pressures (HT-region of the spurrite-merwinite facies).
Novel Selective Depressant of Titanaugite and Implication for Ilmenite Flotation
Authors: Liu Nengyun , Wang Zhen , Xiao Junhui , Wang Hongbin , Deng Bing , Zhang Yushu , Chen Chao
Published: November 2019

This paper studies the effects of sodium polystyrene sulfonate (PSSNa) used as a depressant upon the separation of ilmenite from titanaugite through flotation when sodium oleate (NaOl) is used as a collector by performing single mineral flotation experiments. The depression mechanism of PSSNa on titanaugite flotation was studied by electrokinetic potential and adsorbed amount measurements together with FTIR and XPS detection. Single mineral flotation experiments show that PSSNa is a selective depressant for the separation of ilmenite and titanaugite via flotation with NaOl as the collector. The results of the adsorbed amount tests show that the biggest distinction is in terms of the amount of NaOl adsorbed on the surfaces of ilmenite and titanaugite; the amount is expanded from 2.28 × 10−7 to 9.34 × 10−7 mol/m2 when the dosage of PSSNa is 1 mg/L, as compared with no PSSNa, suggesting that PSSNa is a selective depressant when separating ilmenite and titanaugite through flotation. FTIR testing shows that chemisorption has occurred between the –SO3− groups of the molecular PSSNa and titanaugite surfaces. The results of further XPS testing reveal that PSSNa chemically interacts with Ca/Mg/Al/Fe on the titanaugite surface. The test results of FTIR in combination with XPS confirm that PSSNa stops NaOl from interacting with Mg, Fe, Al, and Ca on the titanaugite surface, and this outcome is the main reason for the widening of the adsorption quantity gap of NaOl on titanaugite and ilmenite surfaces, and titanaugite flotation is suppressed. The results of the comparison flotation testing on actual Panzhihua titanic iron ore (TiO2 grade: 15.63%) with titanaugite as the main gangue show that a better effect is obtained by replacing sodium silicate (SS) with PSSNa, and the recovery of TiO2 using PSSNa is higher than that when using sodium silicate. In a closed circuit flotation test, ilmenite concentrate is obtained with a TiO2 grade of 45.97% and a recovery of 76.32% by using PSSNa as a titanaugite depressant.
Natural and Chemically Modified Post-Mining Clays—Structural and Surface Properties and Preliminary Tests on Copper Sorption
Authors: Jabłońska Beata , Busch Mark , Kityk Andriy V. , Huber Patrick
Published: November 2019

The structural and surface properties of natural and modified Pliocene clays from lignite mining are investigated in the paper. Chemical modifications are made using hydrofluoric acid (HF), sulfuric acid (H2SO4), hydrochloric acid (HCl), nitric acid (HNO3), sodium hydroxide (NaOH), and hydrogen peroxide (H2O2), at a concentration of 1 mol/dm3. Scanning electron microscopy is used to detect the morphology of the samples. Nitrogen adsorption isotherms were recorded to determine the specific surface area (SSA), mesoporosity, microporosity, and fractal dimensions. The raw clay has an SSA of 66 m2/g. The most promising changes in the structural properties are caused by modifications with HF or H2SO4 (e.g., the SSA increased by about 60%). In addition, the raw and modified clays are used in preliminary tests with Cu(II) sorption, which were performed in batch static method at initial Cu(II) concentrations of 25, 50, 80, 100, 200, 300, and 500 mg/dm3 in 1% aqueous suspensions of the clayey material. The maximum sorption of Cu(II) on the raw material was 15 mg/g. The structural changes after the modifications roughly reflect the capabilities of the adsorbents for Cu(II) adsorption. The modifications with HF and H2SO4 bring a similar improvement in Cu(II) adsorption, which is around 20–25% greater than for the raw material. The structural properties of investigated clays and their adsorptive capabilities indicate they could be used as low-cost adsorbents (e.g., for industrial water pretreatment).
AC Electrodeposition of PEDOT Films in Protic Ionic Liquids for Long-Term Stable Organic Electrochemical Transistors
Authors: Ji Jianlong , Zhu Xiaoxian , Han Dan , Li Mangmang , Zhang Qiang , Shu Yang , Cheng Zhengdong , Zhang Wendong , Hua Er , Sang Shengbo
Published: November 2019

Poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS)-based organic electrochemical transistors (OECTs) are widely utilized to construct highly sensitive biosensors. However, the PSS phase exhibits insulation, weak acidity, and aqueous instability. In this work, we fabricated PEDOT OECT by alternating current electrodeposition in protic ionic liquids. The steady-state characteristics were demonstrated to be stable in long-term tests. In detail, the maximum transconductance, the on/off current ratio, and the hysteresis were stable at 2.79 mS, 504, and 0.12 V, respectively. Though the transient behavior was also stable, the time constant could reach 218.6 ms. Thus, the trade-off between switching speed and stability needs to be considered in applications that require a rapid response.
Nanostructured Nickel Aluminate as a Key Intermediate for the Production of Highly Dispersed and Stable Nickel Nanoparticles Supported within Mesoporous Alumina for Dry Reforming of Methane
Authors: Karam Leila , Reboul Julien , El Hassan Nissrine , Nelayah Jaysen , Massiani Pascale
Published: November 2019

Two routes of preparation of mesoporous Ni-alumina materials favoring the intermediate formation of nanostructured nickel-aluminate are presented. The first one involves an aluminum containing MOF precursor used as sacrificial template to deposit nickel while the second is based on a one-pot synthesis combined to an EISA method. As shown by a set of complementary techniques, the nickel-aluminate nanospecies formed after calcination are homogeneously distributed within the developed mesoporous alumina matrices whose porous characteristics vary depending on the preparation method. A special attention is paid to electron-microscopy observations using especially STEM imaging with high chemical sensitivity and EDS elemental mapping modes that help visualizing the extremely high nickel dispersion and highlight the strong metal anchoring to the support that persists after reduction. This leads to active nickel nanoparticles particularly stable in the reaction of dry reforming of methane.
Identification of The Fipronil Resistance Associated Mutations in Nilaparvata lugens GABA Receptors by Molecular Modeling
Authors: Tian Yafeng , Gao Ya , Chen Yanming , Liu Genyan , Ju Xiulian
Published: November 2019

Fipronil, as the first commercialized member of phenylpyrazole insecticides, has been widely used to control planthoppers in China due to its high insecticidal activity and low toxicity to mammals. However, insects have developed resistance to phenylpyrazoles after their long-term use. The resistance mechanism of insects to fipronil has not been well identified, which limited the development of phenylpyrazole insecticides. In the present study, we aimed to elucidate the related fipronil-resistance mechanism in N. lugens GABA receptors by homology modeling, molecular docking, and molecular dynamics. The results indicated that fipronil showed the weakest interaction with the mutant (R0′Q + A2′S) GABA receptors, which is consistent with the experimental study. The binding poses of fipronil were found to be changed when mutations were conducted. These findings verified the novel fipronil-resistance mechanism in silico and provide important information for the design of novel GABAR-targeting insecticides.
Synthesis and Biological Evaluation of Genistein-IR783 Conjugate: Cancer Cell Targeted Delivery in MCF-7 for Superior Anti-Cancer Therapy
Authors: Guan Yang , Zhang Yi , Zou Juan , Huang Li-Ping , Chordia Mahendra D. , Yue Wei , Wu Jin-Jun , Pan Dong-Feng
Published: November 2019

The flavonoid-based natural product genistein is a biologically active compound possessing promising anti-oxidant and anti-cancer properties. Poor pharmacokinetics along with low potency limit however the therapeutic application of genistein in cancer therapy. In order to overcome those limitations and to expand its therapeutic window of efficacy, we sought to covalently attach genistein with a heptamethine cyanine dye—IR 783—for cancer cell targeting and enhanced delivery to tumors. Herein we report the synthesis, a selective detailed characterization and preliminary in vitro/in vivo biological evaluation of genistein-IR 783 conjugate 4. The conjugate 4 displayed improved potency against human breast cancer MCF-7 cells (10.4 ± 1.0 μM) as compared with the parent genistein (24.8 ± 0.5 μM) or IR 783 (25.7 ± 0.7 μM) and exhibited selective high uptake in MCF-7 as against the normal mammary gland MCF-10A cells in various assays. In the cell viability assay, conjugate 4 exhibited over threefold lower potency against MCF-10A cells (32.1 ± 1.1 μM) suggesting that the anti-cancer profile of parent genistein is significantly improved upon conjugation with the dye IR783. Furthermore, the genistein-IR783 conjugate 4 was shown to be especially accumulated in MCF-7 cancer cells by fluorescent intensity measurements and inverted fluorescence microscopy in fixed cells as well as in live cells with time via live cell confocal fluorescence imaging. The mechanism-based uptake inhibition of conjugate 4 was observed with OATPs inhibitor BSP and in part with amiloride, as a macropinocytosis inhibitor. For the first time we have shown amiloride inhibited uptake of cyanine dye by about ~40%. Finally, genistein-IR 783 conjugate 4 was shown to be localized in MCF-7 tumor xenografts of mice breast cancer model via in vivo near infrared fluorescence (NIRF) imaging. In conclusion, conjugation of genistein with cyanine dye IR783 indeed improved its pharmacological profile by cancer cell selective uptake and targeting and therefore warrants further investigations as a new anti-cancer therapeutics derived from natural product genistein.
Development of Bioepoxy Resin Microencapsulated Ammonium-Polyphosphate for Flame Retardancy of Polylactic Acid
Authors: Decsov Kata , Bocz Katalin , Szolnoki Beáta , Bourbigot Serge , Fontaine Gaëlle , Vadas Dániel , Marosi György
Published: November 2019

Ammonium-polyphosphate (APP) was modified by microencapsulation with a bio-based sorbitol polyglycidyl ether (SPE)-type epoxy resin and used as a flame retardant additive in polylactic acid (PLA) matrix. The bioresin-encapsulated APP (MCAPP) particles were characterized using Fourier transform infrared (FTIR) spectroscopy and Raman mapping, particle size distribution was determined by processing of scanning electron microscopic (SEM) images. Interaction between the APP core and the bioresin shell was revealed by combined thermogravimetric analysis (TGA)‑FTIR spectroscopy. The APP to SPE mass ratio of 10 to 2 was found to be optimal in terms of thermal, flammability, and mechanical properties of 15 wt% additive containing biocomposites. The bioresin shell effectively promotes the charring of the APP-loaded PLA composites, as found using TGA and cone calorimetry, and eliminates the flammable dripping of the specimens during the UL-94 vertical burning tests. Thus, the V-0 rating, the increased limiting oxygen index, and the 20% reduced peak of the heat release rate was reached compared to the effects of neat APP. Furthermore, better interfacial interaction of the MCAPP with PLA was indicated by differential scanning calorimetry and SEM observation. The stiff interphase resulted in increased modulus of these composites. Besides, microencapsulation provided improved water resistance to the flame retardant biopolymer system.
Co2TiO4/Reduced Graphene Oxide Nanohybrids for Electrochemical Sensing Applications
Authors: Venegas Constanza J. , Gutierrez Fabiana A. , Eguílaz Marcos , Marco José F. , Reeves-McLaren Nik , Rivas Gustavo A. , Ruiz-León Domingo , Bollo Soledad
Published: November 2019

For the first time, the synthesis, characterization, and analytical application for hydrogen peroxide quantification of the hybrid materials of Co2TiO4 (CTO) and reduced graphene oxide (RGO) is reported, using in situ (CTO/RGO) and ex situ (CTO+RGO) preparations. This synthesis for obtaining nanostructured CTO is based on a one-step hydrothermal synthesis, with new precursors and low temperatures. The morphology, structure, and composition of the synthesized materials were examined using scanning electron microscopy, X-ray diffraction (XRD), neutron powder diffraction (NPD), and X-ray photoelectron spectroscopy (XPS). Rietveld refinements using neutron diffraction data were conducted to determine the cation distributions in CTO. Hybrid materials were also characterized by Brunauer–Emmett–Teller adsorption isotherms, Scanning Electron microscopy, and scanning electrochemical microscopy. From an analytical point of view, we evaluated the electrochemical reduction of hydrogen peroxide on glassy carbon electrodes modified with hybrid materials. The analytical detection of hydrogen peroxide using CTO/RGO showed 11 and 5 times greater sensitivity in the detection of hydrogen peroxide compared with that of pristine CTO and RGO, respectively, and a two-fold increase compared with that of the RGO+CTO modified electrode. These results demonstrate that there is a synergistic effect between CTO and RGO that is more significant when the hybrid is synthetized through in situ methodology.
Influence of Nanoscale Textured Surfaces and Subsurface Defects on Friction Behaviors by Molecular Dynamics Simulation
Authors: Tong Ruiting , Quan Zefen , Zhao Yangdong , Han Bin , Liu Geng
Published: November 2019

In nanomaterials, the surface or the subsurface structures influence the friction behaviors greatly. In this work, nanoscale friction behaviors between a rigid cylinder tip and a single crystal copper substrate are studied by molecular dynamics simulation. Nanoscale textured surfaces are modeled on the surface of the substrate to represent the surface structures, and the spacings between textures are seen as defects on the surface. Nano-defects are prepared at the subsurface of the substrate. The effects of depth, orientation, width and shape of textured surfaces on the average friction forces are investigated, and the influence of subsurface defects in the substrate is also studied. Compared with the smooth surface, textured surfaces can improve friction behaviors effectively. The textured surfaces with a greater depth or smaller width lead to lower friction forces. The surface with 45° texture orientation produces the lowest average friction force among all the orientations. The influence of the shape is slight, and the v-shape shows a lower average friction force. Besides, the subsurface defects in the substrate make the sliding process unstable and the influence of subsurface defects on friction forces is sensitive to their positions.
Effects of Phytochemicals on Blood Pressure and Neuroprotection Mediated Via Brain Renin-Angiotensin System
Authors: Kim Hye Lin , Kim Woo Kyoung , Ha Ae Wha
Published: November 2019

Background: The renin-angiotensin system (RAS) in the brain plays a crucial role in maintaining blood pressure as well as neuroprotection. This study compared the effects of curcumin, quercetin, and saponin on blood pressure, the brain RAS, and cholinergic system using perindopril, an angiotensin converting enzyme inhibitor (ACEI), as a positive control. Methods: Five-week-old male mice were stabilized and randomly assigned into a control group (n = 8), three phytochemical-treated groups (curcumin (n = 8), quercetin (n = 8), and saponin (n = 8)), and a positive control group (n = 8). The groups treated with the phytochemical were orally administered daily at a dose of 50 mg/kg body weight of phytochemicals. During the experiments, the weight and dietary intakes were measured regularly. After experiments, the brain tissue was homogenized and centrifuged for an additional assay. The concentrations of ACE, angiotensin II (AngII), and aldosterone levels were measured, and the mRNA expressions of renin and ACE were measured. As biomarkers of neuroprotection, the concentrations of acetylcholine (ACh) as well as the concentration and activity of acetylcholine esterase (AChE) were measured. Results: After 4 weeks of treatment, the perindopril group showed the lowest blood pressure. Among the groups treated with the phytochemicals, treatment with curcumin and saponin significantly reduced blood pressure, although such effect was not as high as that of perindopril. Among phytochemicals, curcumin treatment significantly inhibited the concentration and activity of ACE, concentration of AngII, and mRNA expression of ACE. All phytochemical treatments significantly increased the concentration of ACh. The levels of AChE activity in groups exposed to curcumin or saponin (not quercetin) were significantly inhibited, Conclusion: Curcumin administration in rats reduced blood pressure by blocking the brain RAS components and protected the cholinergic system in brain by inhibiting the activity of AChE.
Factors Associated with the Early Initiation of Breastfeeding in Economic Community of West African States (ECOWAS)
Authors: Ezeh Osita , Ogbo Felix , Stevens Garry , Tannous Wadad , Uchechukwu Osuagwu , Ghimire Pramesh , Agho Kingsley ,   Global Maternal and Child Health Research Collaboration (GloMACH)
Published: November 2019

The early initiation of breastfeeding (EIBF) within one hour after birth enhanced mother–newborn bonding and protection against infectious diseases. This paper aimed to examine factors associated with EIBF in 13 Economic Community of West African States (ECOWAS). A weighted sample of 76,934 children aged 0–23 months from the recent Demographic and Health Survey dataset in the ECOWAS for the period 2010 to 2018 was pooled. Survey logistic regression analyses, adjusting for country-specific cluster and population-level weights, were used to determine the factors associated with EIBF. The overall combined rate of EIBF in ECOWAS was 43%. After adjusting for potential confounding factors, EIBF was significantly lower in Burkina Faso, Cote d’Ivoire, Guinea, Niger, Nigeria, and Senegal. Mothers who perceived their babies to be average and large at birth were significantly more likely to initiate breastfeeding within one hour of birth than those mothers who perceived their babies to be small at birth. Mothers who had a caesarean delivery (AOR = 0.28, 95%CI = 0.22–0.36), who did not attend antenatal visits (ANC) during pregnancy, and delivered by non-health professionals were more likely to delay initiation of breastfeeding beyond one hour after birth. Male children and mothers from poorer households were more likely to delay introduction of breastfeeding. Infant and young child feeding nutrition programs aimed at improving EIBF in ECOWAS need to target mothers who underutilize healthcare services, especially mothers from lower socioeconomic groups.
Vitamin D Food Fortification and Nutritional Status in Children: A Systematic Review of Randomized Controlled Trials
Authors: Brandão-Lima Paula Nascimento , Santos Beatriz da Cruz , Aguilera Concepción Maria , Freire Analícia Rocha Santos , Martins-Filho Paulo Ricardo Saquete , Pires Liliane Viana
Published: November 2019

Children are in the risk group for developing hypovitaminosis D. Several strategies are used to reduce this risk. Among these, fortification of foods with vitamin D (25(OH)D) has contributed to the achievement of nutritional needs. This systematic review aims to discuss food fortification as a strategy for maintenance or recovery of nutritional status related to vitamin D in children. The work was developed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and registered in the International prospective register of systematic reviews (PROSPERO) database (CRD42018052974). Randomized clinical trials with children up to 11 years old, who were offered vitamin D-fortified foods, and who presented 25(OH)D concentrations were used as eligibility criteria. After the selection stages, five studies were included, totaling 792 children of both sexes and aged between two and 11 years. Interventions offered 300–880 IU of vitamin D per day, for a period of 1.6–9 months, using fortified dairy products. In four of the five studies, there was an increase in the serum concentrations of 25(OH)D with the consumption of these foods; additionally, most children reached or maintained sufficiency status. Moreover, the consumption of vitamin D-fortified foods proved to be safe, with no concentrations of 25(OH)D > 250 nmol/L. Based on the above, the fortification of foods with vitamin D can help maintain or recover the nutritional status of this vitamin in children aged 2–11 years. However, it is necessary to perform additional randomized clinical trials in order to establish optimal doses of fortification, according to the peculiarities of each region.
Applying Methods for Postnatal Growth Assessment in the Clinical Setting: Evaluation in a Longitudinal Cohort of Very Preterm Infants
Authors: Izquierdo Renau Montserrat , Aldecoa-Bilbao Victoria , Balcells Esponera Carla , del Rey Hurtado de Mendoza Beatriz , Iriondo Sanz Martin , Iglesias-Platas Isabel
Published: November 2019

Aim: To analyze different methods to assess postnatal growth in a cohort of very premature infants (VPI) in a clinical setting and identify potential early markers of growth failure. Methods: Study of growth determinants in VPI (≤32 weeks) during hospital stay. Nutritional intakes and clinical evolution were recorded. Growth velocity (GV: g/kg/day), extrauterine growth restriction (%) (EUGR: weight < 10th centile, z-score < −1.28) and postnatal growth failure (PGF: fall in z-score > 1.34) at 36 weeks postmenstrual age (PMA) were calculated. Associations between growth and clinical or nutritional variables were explored (linear and logistic regression). Results: Sample: 197 VPI. GV in IUGR patients was higher than in non-IUGRs (28 days of life and discharge). At 36 weeks PMA 66.0% of VPIs, including all but one of the IUGR patients, were EUGR. Prevalence of PGF at the same time was 67.4% (IUGR patients: 48.1%; non-IUGRs: 70.5% (p = 0.022)). Variables related to PGF at 36 weeks PMA were initial weight loss (%), need for oxygen and lower parenteral lipids in the first week. Conclusions: The analysis of z-scores was better suited to identify postnatal growth faltering. PGF could be reduced by minimising initial weight loss and assuring adequate nutrition in patients at risk.
Further Exploration of Sucrose-Citric Acid Adhesive: Synthesis and Application on Plywood
Authors: Sun Shijing , Zhao Zhongyuan , Umemura Kenji
Published: November 2019

The development of eco-friendly adhesives is a major research direction in the wood-based material industry. Previous research has already demonstrated the mixture of sucrose and citric acid could be utilized as an adhesive for the manufacture of particleboard. Herein, based on the chemical characteristics of sucrose, a synthesized sucrose-citric acid (SC) adhesive was prepared, featuring suitable viscosity and high solid content. The investigation of synthesis conditions on the bond performance showed that the optimal mass proportion between sucrose and citric acid was 25/75, the synthesis temperature was 100 °C, and the synthesis time was 2 h. The wet shear strength of the plywood bonded with SC adhesive, which was synthesized at optimal conditions and satisfied the China National Standard GB/T 9846-2015. The synthesis mechanism was studied by both 13C NMR analysis and HPLC, and the chemical composition manifesting caramelization reaction occurred during the synthesis process. The results of ATR FT-IR indicated the formation of a furan ring, carbonyl, and ether groups in the cured insoluble matter of the SC adhesive, which indicated dehydration condensation as the reaction mechanism between sucrose and citric acid.
Injection Molding of Highly Filled Polypropylene-based Biocomposites. Buckwheat Husk and Wood Flour Filler: A Comparison of Agricultural and Wood Industry Waste Utilization
Authors: Andrzejewski Jacek , Barczewski Mateusz , Szostak Marek
Published: November 2019

The study presents a comparative analysis for two types of polymer fillers used during the processing of polypropylene by the injection molding technique. The aim of the study was to assess the usefulness of buckwheat husk waste as an alternative to the widely used wood fiber fillers. For this purpose, we prepared composite samples containing 10, 30 and 50 wt % of the filler, which were subjected to mechanical tests, thermal analysis, and structural observations in order to evaluate and compare their properties. Additionally, we evaluated the effectiveness of the composite system’s compatibility by using maleic anhydride grafted polypropylene (PP-g-MA). The results of mechanical tests confirmed a more effective reinforcement mechanism for wood fibers; however, with the addition of PP-g-MA compatibilizer, these differences were significantly reduced: we observed a 14% drop for tensile modulus and 5% for strength. This suggests high susceptibility to this type of adhesion promoter, also confirmed by SEM observations. The paper also discusses rheological measurements conducted on a rotational rheometer, which allowed to confirm more favorable flow characteristics for composites based on buckwheat husks.
Electrically Self-Healing Thermoset MWCNTs Composites Based on Diels-Alder and Hydrogen Bonds
Authors: Macedo R. Lima Guilherme , Orozco Felipe , Picchioni Francesco , Moreno-Villoslada Ignacio , Pucci Andrea , Bose Ranjita K. , Araya-Hermosilla Rodrigo
Published: November 2019

In this work, we prepared electrically conductive self-healing nanocomposites. The material consists of multi-walled carbon nanotubes (MWCNT) that are dispersed into thermally reversible crosslinked polyketones. The reversible nature is based on both covalent (Diels-Alder) and non-covalent (hydrogen bonding) interactions. The design allowed for us to tune the thermomechanical properties of the system by changing the fractions of filler, and diene-dienophile and hydroxyl groups. The nanocomposites show up to 1 × 104 S/m electrical conductivity, reaching temperatures between 120 and 150 °C under 20–50 V. The self-healing effect, induced by electricity was qualitatively demonstrated as microcracks were repaired. As pointed out by electron microscopy, samples that were already healed by electricity showed a better dispersion of MWCNT within the polymer. These features point toward prolonging the service life of polymer nanocomposites, improving the product performance, making it effectively stronger and more reliable.
Prosthetic and Mechanical Parameters of the Facial Bone under the Load of Different Dental Implant Shapes: A Parametric Study
Authors: Cicciù Marco , Cervino Gabriele , Terranova Antonella , Risitano Giacomo , Raffaele Marcello , Cucinotta Filippo , Santonocito Dario , Fiorillo Luca
Published: November 2019

In recent years the science of dental materials and implantology have taken many steps forward. In particular, it has tended to optimize the implant design, the implant surface, or the connection between implant and abutment. All these features have been improved or modified to obtain a better response from the body, better biomechanics, increased bone implant contact surface, and better immunological response. The purpose of this article, carried out by a multidisciplinary team, is to evaluate and understand, through the use also of bioengineering tests, the biomechanical aspects, and those induced on the patient’s tissues, by dental implants. A comparative analysis on different dental implants of the same manufacturer was carried out to evaluate biomechanical and molecular features. Von Mises analysis has given results regarding the biomechanical behavior of these implants and above all the repercussions on the patient’s tissues. Knowing and understanding the biomechanical characteristics with studies of this type could help improve their characteristics in order to have more predictable oral rehabilitations.
Quantifying Age-Related Differences of Ankle Mechanical Properties Using a Robotic Device
Authors: Martelli Francesca , Taborri Juri , Del Prete Zaccaria , Palermo Eduardo , Rossi Stefano
Published: November 2019

A deep analysis of ankle mechanical properties is a fundamental step in the design of an exoskeleton, especially if it is to be suitable for both adults and children. This study aims at assessing age-related differences of ankle properties using pediAnklebot. To achieve this aim, we enrolled 16 young adults and 10 children in an experimental protocol that consisted of the evaluation of ankle mechanical impedance and kinematic performance. Ankle impedance was measured by imposing stochastic torque perturbations in dorsi-plantarflexion and inversion-eversion directions. Kinematic performance was assessed by asking participants to perform a goal-directed task. Magnitude and anisotropy of impedance were computed using a multiple-input multiple-output system. Kinematic performance was quantified by computing indices of accuracy, smoothness, and timing. Adults showed greater magnitude of ankle impedance in both directions and for all frequencies, while the anisotropy was higher in children. By analyzing kinematics, children performed movements with lower accuracy and higher smoothness, while no differences were found for the duration of the movement. In addition, adults showed a greater ability to stop the movement when hitting the target. These findings can be useful to a proper development of robotic devices, as well as for implementation of specific training programs.