bluuebunny/crossref_metadata_2025_split huggingface dataset:
PREPARATION AND STABILITY OF SILVER AND PALLADIUM NANOPARTICLES STABILIZED BY POLYETHER LAPROL 5003 IN N,N – DIMETHYLFORMAMIDE MEDIA
Authors: Bespalov Alexander V. , Ivanova Yana O. 
Published: May 2019

This paper is devoted to obtaining and investigating the stability of silver and palladium sols in N,N-dimethylformamide medium. Due to the unique properties exhibited by metals in the nanosized state, metallic nanoparticles are gaining increasing importance in various fields of application, science and technology. This makes the task of obtaining stable metal sols extremely urgent. The synthesis of aggregate-resistant organosols of metals is associated with a number of problems, since the metal sols obtained in organic media are much less stable than hydrosols. For this reason, there arises the challenge of choosing an appropriate stabilizer. In this study, the stabilizer was branched polyester Laprol 5003. A distinctive feature of the synthesis of silver sols was the absence of a special reducing agent, since N,N-dimethylformamide, used as a solvent, recovers silver cations itself. As a result, stable sols of silver and palladium have been obtained in N,N-dimethylformamide medium. Sodium borohydride was used as the reducing agent for the synthesis of palladium nanoparticles. Spectral studies of the resulting sols were carried out. The silver and palladium nanoparticles were sized up by scanning electron microscopy. The procedure has shown that the average size of the silver particles formed in the N,N-dimethylformamide medium is 4 ± 2 nm, which is substantially smaller than the particles obtained in isopropanol medium by the borohydride method. The silver sols aggregation in dimethylformamide under the action of potassium thiocyanate was studied via optical absorption spectroscopy. It has been found that the stability of the silver sol in dimethylformamide to the electrolyte is higher than that of the sol obtained in isopropanol. It has also been detected that several absorption bands are present in the optical spectrum of the palladium sol in dimethylformamide. The effect of the stabilizing polyester concentration on the stability of silver and palladium sols in N,N-dimethylformamide was studied. The result is that when the concentration of Laprol 5003 exceeds some quantity, a sharp increase in the aggregation time of sols is observed, which indicates a significant increase in their stability.
Performance économique des services d’eau potable et d’assainissement en Algérie, cas de Souk-Ahras
Authors: Boukhari Sofiane , de Miras Claude 
Published: May 2019

Les services d'eau potable et d’assainissement (SEPA) sont confrontés à de nombreuses contraintes de nature institutionnelle, technique et financière. Les attentes des clients et, plus largement, la dimension sociale et environnementale déterminent également l’offre de services. L’objectif de cet article est d’analyser la situation économique en vue de l’amélioration de la performance des SEPA en Algérie, en prenant comme exemple le département de Souk-Ahras. Cette recherche englobe une analyse empirique (technique et financière) de la gestion des SEPA, en analysant des données collectées auprès des services chargés de la gestion des SEPA du département de Souk-Ahras. D’après nos résultats, les tarifs de l’eau potable et de l’assainissement ne couvrent ni les coûts d’exploitation ni les coûts d’investissement de réhabilitation et renouvellement et les grilles tarifaires font bénéficier les gros consommateurs des tarifs « solidarité » pour les premières tranches de facturation.
Evaluation of dislocations under the electrodes of GaN pn diodes by X-ray topography
Authors: Kanechika Masakazu , Yamaguchi Satoshi , Imanishi Masayuki , Mori Yusuke 
Published: May 2019

Abstract
We have successfully obtained the clear images of the dislocation mapping even under the electrodes of the GaN vertical pn diodes by reflection X-ray topography using monochromatic synchrotron radiation (SPring-8, BL16B2 & BL20B2). This is a powerful analysis because of the non-destructive and rapid tool unlike the etch-pit method and TEM (transmission electron microscopy). This allows us to directly study the relationship between the dislocation and the leakage current. Applying this method to vertical pn diodes on Na-flux GaN substrates, we found that leakage current per dislocation is of the order of 10 pA. This analysis has a potential to reveal the killer dislocation structure.
A mathematical landmark-based method for measuring worn molars in hominoid systematics
Authors: Dykes Susan J. , Pilbrow Varsha C. 
Published: May 2019

Worn teeth pose a major limitation to researchers in the fields of extinct and extant hominoid systematics because they lack clearly identifiable anatomical landmarks needed to take measurements on the crown enamel surface and are typically discarded from a study. This is particularly detrimental when sample sizes for some groups are already characteristically low, if there is an imbalance between samples representing populations, sexes or dietary strategies, or if the worn teeth in question are type specimens of fossil species or other key specimens. This study proposes a methodology based predominantly on mathematically-derived landmarks for measuring size and shape features of molars, irrespective of wear. With 110 specimens of lower second molars from five species of extant hominoids (Pan troglodytes, P. paniscus, Gorilla gorilla, G. beringei, Homo sapiens), n ≥ 20 per species, n ≥ 10 per subspecies, good species separation in morphospace is achieved in a principal components analysis. Classification accuracy in a discriminant function analysis is 96.4% at the species level and 88.2% at the subspecies level (92.7% and 79.1%, respectively, on cross-validation). The classification accuracy compares favorably to that achieved by anatomically-derived measurements based on published research (94% and 84% at the species and subspecies level respectively; 91% and 76% on cross-validation). The mathematical landmarking methodology is rapid and uncomplicated. The results support the use of mathematical landmarks to enable the inclusion of worn molar teeth in dental studies so as to maximize sample sizes and restore balance between populations and/or sexes in hominoid systematic studies.
Syntactic Priming: Improving Senior High School Learners' Writing Proficiency
Authors: Alojado Meraflor Montajes 
Published: May 2019

Syntactic priming is a tendency for a speaker or writer to repeat of a recently produced or heard in a language structure by processing and sharing the same underlying syntactic structure which serves as the intervention for the students who were having difficulties in writing specifically on coordinating conjunctions. It would enhance the secondary students' writing proficiency in sentence construction to produce better-written outputs not only in educational context but also to the corporate world as well. This experimental research investigated the significant difference on the Grade 11 students Section Tulip before and after using syntactic priming as an intervention in writing. The researcher made use of structured test like pre-test and post-test to measure the effectiveness of syntactic priming in students' writing performances. Statistical techniques such as mean and t-test were also used. Analyzed data revealed that there was an increased on their scored mean from pre-test to post-test among thirty identified participants as poor writers. Furthermore, there was a significant difference between pre-test and post-test since the P-Value (0.000) was lesser than 0.5, the null hypothesis was rejected with 95% level of confidence based on the students' scores before and after taking the intervention which was not the same.
Design, Development, and Evaluation of a Microgrid for the Energy Management in a Small Poultry
Authors: Saavedra, Jr. Nicasio 
Published: May 2019

The Development of an Energy Management System for a Small Poultry is another solution to help the poultry raisers/farmers obtain a reasonable and renewable source of energy. A microgrid can be characterized by its integration of distributed energy resources and controllable loads. Such integration brings unique challenges to the microgrid management and control which can be significantly different from conventional power systems. The developed device is composed of the following major components: brooder, where the chicks are placed, and the electronic devices are installed; a relay which monitors and controls the power supply of the system; a solar panel and battery that captures and saves the energy from the sun; and an inverter that converts direct current to alternating current. The total power of the poultry is 33W and used 560W per day of the power source from the battery. Test results showed that the contribution of saving power consumption reached 83% and losses are 35.75%. The voltage of the battery in 100% reached to 12.4V down to 2% has 10.45V. The actual testing for amperes of the bulb is 2.5A, the counter has 0.6A, and the temperature has 0.25A. The actual wattage of bulb is 30W, and temperature has 3W. The performance of the prototype was evaluated by twenty (20) panel of evaluators composed of electronic technicians and engineers, agriculturists, and poultry farmers using the Technological University of the Philippines (TUP) Evaluation Instrument for Prototype Developed. The prototype got a grand mean of 4.72 with a descriptive rating of â€œExcellentâ€ which proves that the project reduces the consumption of electricity from the commercial power distribution.
Salmonella Carriage among Patients in Fako Division, Cameroon: A Cross-sectional Study of Its Prevalence and Associated Risk Factors
Authors: Nkeza Awung , Anna Njunda Longdoh , Jules Clement Assob Nguedia 
Published: May 2019

Introduction: This study was aimed at evaluating the prevalence and the risk factors of Salmonellosis in patients who were consulted in some medical facilities in Fako Division of Cameroon.
Methods: A cross-sectional study was carried out from November 2017 to November 2018 in three hospitals in Fako division of Cameroon; Tiko District Hospital, Mutengene Medical Center and Buea Regional Hospital. A total of 510 individuals presenting with symptoms of Salmonellosis were administered comprehensive questionnaire. Salmonella enterica strains were cultured from stool and identified using API 20E. Data was entered into Excel and imported into STATA v.12 for Windows, for statistical analysis. Odd ratios were calculated to determine the risk factors associated with Salmonellosis.
Results: Fifty Salmonella enterica strains were isolated giving a prevalence of 9.8%. Univariate analysis showed the following risk factors for Salmonellosis: area of residence; suburban p=0.037, OR=5.7 95% CI (1.1-30.03) and rural p=0.077, OR=2.3 95% CI (0.91-5.76), overcrowding (2 persons in a room) p=0.047, OR=2.3 95% CI (1.01-5.41); drinking tap-water, p=0.032 OR=0.38(.16-.092); left-over drugs from the pharmacy, p=0.906 OR= 1.07(0.32-3.55) as being relatively significant risk factors.
Conclusion: The prevalence was found to be higher among the very young and older people greater than 45 years. The risk factors identified in this study are: age, area of residence; overcrowding; consuming locally prepared yoghurt or Kosam; eating out or auto-medication by taking leftover drugs. These findings highlight the need of reinforcement of hygiene promotion especially in infants and overpopulated communities, educate on proper prescription and usage of drugs, in addition to the intensification of environmental interventions.
Characterization of Sesquiterpenes and Antibacterial Activities of Extracts from Piliostigma reticulatum (DL.) Hochst and Cleistopholis patens (Benth.) Engl & Diels against Shigella dysenteriae and Streptococcus pyogenes
Authors: Daniels A. O. , Owoyemi O. O. , Famurewa O. , Oluyege J. O. 
Published: May 2019

Aim: The study characterized sesquiterpenes from the bark extracts of Piliostigma reticulatum and Cleistopholis patens and subsequently tested the extracts for their antibacterial activities. Methodology: Ground stem barks of P. reticulatum and C. patens were obtained and extracted with ethyl acetate. The extract from both plants were screened for antibacterial activities against Shigella dysenteriae and Streptococcus pyogenes using the agar well diffusion method. Furthermore, fractions obtained from the crude extracts were also assayed for antibacterial efficacy using the disc diffusion method. The phyto-constituents of the extracts were identified using Gas chromatography and mass spectra (GC-MS) and subsequent characterization was achieved via Nuclear Magnetic Resonance Spectroscopy (NMR).
Results: The results showed that P. reticulatum extract had more antibacterial activities on S. dysenteriae with zones of inhibition ranging from 6 mm – 14 mm while it had lesser inhibitory effect against S. pyogenes with zones of inhibition of 10 mm and 8 mm at concentrations of 100 mg/mL and 80 mg/mL respectively. However, C. patens was effective against S. pyogenes with zones of inhibition of 18 mm, 16 mm, 14 mm, 13 mm, and 8 mm at concentrations of 100, 60, 40, 20 and 10 mg/mL respectively. Crude extracts from both plants exhibited higher antibacterial activity compared to purified fractions against test organisms. A number of five (5) Sesquiterpenes (azulenes, alpha and beta pinene, Germacrene D, Limonene, and Farnesol) were identified from the extracts of both plants.
Conclusion: The presence of sesquiterpenes in P. reticulatum and C. patens could be responsible for the antibacterial activities on the test organisms (S. dysenteriae and S. pyogenes) evaluated in this study and subsequently justify their use in folkloric medicine. Hence, the extracts obtained from P. reticulatum and C. patens could be considered as a potential and rich source of antibacterial agent to control infections posed by the test organisms (S. dysenteriae and S. pyogenes).
Comparison of pancreatic respiratory motion management with three abdominal corsets for particle radiation therapy: Case study
Authors: Dolde Kai , Schneider Sergej , Stefanowicz Sarah , Alimusaj Merkur , Flügel Beate , Saito Nami , Troost Esther G. C. , Pfaffenberger Asja , Hoffmann Aswin L. 
Published: May 2019

AbstractBackground and purposeAbdominal organ motion seriously compromises the targeting accuracy for particle therapy in patients with pancreatic adenocarcinoma. This study compares three different abdominal corsets regarding their ability to reduce pancreatic motion and their potential usability in particle therapy.Materials and methodsA patient‐individualized polyurethane (PU), a semi‐individualized polyethylene (PE), and a patient‐individualized three‐dimensional‐scan based polyethylene (3D‐PE) corset were manufactured for one healthy volunteer. Time‐resolved volumetric four‐dimensional‐magnetic resonance imaging (4D‐MRI) and single‐slice two‐dimensional (2D) cine‐MRI scans were acquired on two consecutive days to compare free‐breathing motion patterns with and without corsets. The corset material properties, such as thickness variance, material homogeneity in Hounsfield units (HU) on computed tomography (CT) scans, and manufacturing features were compared. The water equivalent ratio (WER) of corset material samples was measured using a multi‐layer ionization chamber for proton energies of 150 and 200 MeV.ResultsAll corsets reduced the pancreatic motion on average by 9.6 mm in inferior–superior and by 3.2 mm in anterior‐posterior direction. With corset, the breathing frequency was approximately doubled and the day‐to‐day motion variations were reduced. The WER measurements showed an average value of 0.993 and 0.956 for the PE and 3DPE corset, respectively, and of 0.298 for the PU corset. The PE and 3DPE corsets showed a constant thickness of 2.8 ± 0.2 and 3.8 ± 0.2 mm, respectively and a homogeneous material composition with a standard deviation (SD) of 31 and 32 HU, respectively. The PU corset showed a variable thickness of 4.2 − 25.6 mm and a heterogeneous structure with air inclusions with an SD of 113 HU.ConclusionAbdominal corsets may be effective devices to reduce pancreatic motion. For particle therapy, PE‐based corsets are preferred over PU‐based corset due to their material homogeneity and constant thickness.
Fast Yet Quantum‐Efficient Few‐Layer Vertical MoS2 Photodetectors
Authors: Maeso David , Castellanos‐Gomez Andres , Agraït Nicolas , Rubio‐Bollinger Gabino 
Published: May 2019

AbstractSemiconducting 2D materials, such as molybdenum disulfide (MoS2) and other members of the transition‐metal dichalcogenide family, have emerged as promising materials for applications in high‐performance nanoelectronics that exhibit excellent electrical and optical properties. Highly efficient photocurrent (PC) generation is reported in vertical few‐layer MoS2 devices contacted with semitransparent metallic electrodes. The light absorption of the device can be improved by fabricating vertical photodevices using few‐layer flakes, achieving a photoresponse of up to 0.11 A W−1 and an external quantum efficiency (EQE) of up to 30%. Because of the vertical design, the distance between electrodes can be kept in the range of a few nanometers, thus substantially reducing the collection time of photogenerated carriers and increasing the efficiency of the devices. The wavelength‐dependent PC, photoresponsivity, and EQE are measured over a photon energy range from 1.24 to 2.58 eV. Compared to previous in‐plane and vertical devices, these vertical few‐layer MoS2 photodevices exhibit very short response time, ≈60 ns, and a cutoff frequency of 5.5 MHz, while maintaining high photoresponsivity.
Room‐Temperature Reversible and Nonvolatile Tunability of Electrical Properties of Cr‐Doped In2O3 Semiconductor Thin Films Gated by Ferroelectric Single Crystal and Ionic Liquid
Authors: Xu Meng , Yan Jian‐Min , Chen Ting‐Wei , Xu Zhi‐Xue , Wang Hui , Guo Lei , Gao Guan‐Yin , Yan Shu‐Ying , Wang Fei‐Fei , Zhang Jin‐Xing , Zhao Weiyao , Li Xiao‐Guang , Luo Hao‐Su , Zheng Ren‐Kui 
Published: May 2019

AbstractIntegration of different functional materials into a device in which the physical properties can be tuned using an electric field in a reversible and nonvolatile manner is highly desired for the fabrication of compact and energy‐efficient multifunctional electronic devices. The integration of In2O3‐based semiconductor thin films with ferroelectric 0.71PbMg1/3Nb2/3O3‐0.29PbTiO3 (PMN‐0.29PT) single crystals in ferroelectric‐field‐effect‐transistor devices that allow for the tuning of carrier density, carrier type, Fermi level, and their related properties in a reversible and nonvolatile manner, is reported. Specifically, gating of In2–x
Crx
O3 (x = 0, 0.02, 0.05, 0.08, 0.11) films with a PMN‐0.29PT layer provides a means to reversibly tune and modulate the resistivity of the films up to an on‐and‐off ratio of 5.2 × 104% in a nonvolatile manner at room temperature. Such resistivity modulation is associated with reversible and nonvolatile transformation of the carrier type between n‐type and p‐type due to polarization switching. Additionally, reversible switching of resistivity is realized utilizing DEME‐TFSI ionic liquid as a top‐gate material. These results demonstrate that electrical‐voltage control of physical properties using PMN‐xPT as both substrate and gating material provides a highly effective approach to study the carrier‐density/type‐related physical properties of semiconductor films.
Highly Stretchable and Self‐Healable MXene/Polyvinyl Alcohol Hydrogel Electrode for Wearable Capacitive Electronic Skin
Authors: Zhang Jiaqi , Wan Lijia , Gao Yang , Fang Xiaoliang , Lu Ting , Pan Likun , Xuan Fuzhen 
Published: May 2019

AbstractCapacitive strain sensors could become an important component of electronic skin (E‐skin) due to their low hysteresis and high linearity. However, to fully mimic the functionality of human skin, a capacitive strain sensor should be stretchable and self‐healable. The development of such a sensor is limited by electrode materials which generally lack self‐healability and/or stretchability. A highly stretchable and self‐healing MXene (Ti3C2Tx)/polyvinyl alcohol (PVA) hydrogel electrode is developed for use in capacitive strain sensors for E‐skin. The incorporation of MXene into the PVA enhances the conductivity and self‐healability of the hydrogel. The electrode exhibits high stretchability at break (≈1200%) and instantaneous self healing (healing time ≈ 0.15 s). A capacitive sensor based on these electrodes shows high linearity, up to 200%, low hysteresis, a sensitivity of ≈0.40, and good mechanical durability (a 5.8% reduction in relative capacitance change after 10 000 cycles). Moreover, this sensor maintains its performance after a self‐healing test, proving its potential for the monitoring of human motion.
Loss of function BMP4 mutation supports the implication of the BMP/TGF‐β pathway in the etiology of combined pituitary hormone deficiency
Authors: Rodríguez‐Contreras Francisco J. , Marbán‐Calzón Mercedes , Vallespín Elena , del Pozo Ángela , Solís‐López Mario , Lobato‐Vidal Nerea , Fernández‐Elvira María , del Valle Rex‐Romero María , Heath Karen E. , González‐Casado Isabel , Campos‐Barros Ángel 
Published: May 2019

AbstractDespite BMP4 signaling being critical to Rathke's pouch induction and maintenance during early stages of pituitary development, its implication in the etiology of combined pituitary hormone deficiency (CPHD) and other clinical presentations of congenital hypopituitarism has not yet been definitely demonstrated. We report here the first CPHD patient with a de novo pathogenic loss‐of‐function variant in BMP4. A 6‐year‐old boy, with macrocephaly, myopia/astigmatism, mild psychomotor retardation, anterior pituitary hypoplasia and ectopic posterior pituitary, clinically diagnosed with growth hormone deficiency, and central hypothyroidism, was referred for genetic analysis of CPHD. Targeted NGS analysis with a custom panel (n = 310 genes) identified a novel heterozygous de novo nonsense variant, NM_001202.5:c.794G > A, p.(Trp265*) in BMP4, which introduces a premature stop codon in the BMP4 pro‐domain, impairing the transcription of the TGF‐β mature peptide domain. Additional relevant variants in other genes implicated in pituitary development signaling pathways such as SMAD4 and E2F4 (BMP/TGF‐pathway), ALMS1 (NOTCH‐pathway), and TSHZ1 (Prokineticin‐pathway), were also identified. Our results support the implication of the BMP/TGF‐β signaling pathway in the etiology of CPHD and suggest that oligogenic contribution of additional inherited variants may modify the phenotypic expressivity of BMP4 pathogenic variants.
Oxygen Vacancy Diffusion and Condensation in Lithium‐Ion Battery Cathode Materials
Authors: Lee Sanghan , Jin Wooyoung , Kim Su Hwan , Joo Se Hun , Nam Gyutae , Oh Pilgun , Kim Young‐Ki , Kwak Sang Kyu , Cho Jaephil 
Published: May 2019

AbstractOxygen vacancies (OV) are native defects in transition metal (TM) oxides and their presence has a critical effect on the physicochemical properties of the oxide. Metal oxides are commonly used in lithium‐ion battery (LIB) cathodes and there is still a lack of understanding of the role of OVs in LIB research field. Here, we report on the behavior of OVs in a single‐crystal LIB cathode during the non‐equilibrium states of charge and discharge. We found that microcrack evolution in a single crystal occurs due to OV condensation in specific crystallographic orientations generated by the continuous migration of OVs and TM ions. Moreover, understanding the effects of the presence and diffusion of OVs in metal oxides enables the elucidation of most of the conventional mechanisms of capacity fading in LIBs and provides new insights for new electrochemical applications.