bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of age on the functioning of hemostasis system during hip joint endoprosthesis
Authors: Volokitina Elena , Antropova Irina , Yershov Anton , Chelchushev Dmitry , Kutepov Sergey
Published: July 2020

The study was performed on 109 osteoarthritis patients who underwent hip joint endoprosthetics; the effect of age on changes in hemostasis system, blood loss level and deep veins thrombosis development in the background of standard prevention with low-molecular heparins were studied. Before the surgery, it was determined that 56 elderly patients (60.3 ± 6.4 years) compared to 53 middle-aged patients (41.8 ± 6.8 years) had a significantly higher initial and postoperative endothelial dysfunction, higher fibrin formation and lower anticoagulant potential; however, it was found that on the background of pharmacological anticoagulant therapy the changes in the hemostasis functioning in elderly patients did not lead to an increase of either blood loss or the number of thromboses.
Relationship evaluation of health status and mineral metabolism in children of newborn and early age
Authors: Krylova Lidia , Levchuk Larisa , Tiunova Elena
Published: July 2020

The article presents the study results of fluorine availability of breastfed and early age children depending on the feeding type and in relation to the main bone forming minerals. The content of fluorine and calcium in biological fluids (breast milk, urine) has been determined. Clinical and laboratory indicators reflecting the impairment of fluorine metabolism in children were described. With normal availability of calcium, symptoms of musculoskeletal damage caused by fluorine deficiency have been detected. Diagnosed fluorine-deficient state reflects the disruption of chemical interaction between the main mineral-forming elements of bone tissue — fluorine and calcium. A new way of nutritive support has been proposed for prevention of fluorodeficiency conditions in children.
Development of a bioaction complex for the onychodystrophy treatment
Authors: Gurkovskaya Evgenia , Bolotova Anna , Savchenko Natalia , Petrov Alexandr , Shubina Alexandra
Published: July 2020

This article is devoted to the problem of onychodystrophy treatment. The purpose of the study was to develop a bioactive complex for the external treatment of onychodystrophies. We conducted a prospective cohort study to determine the emotional status and life quality of patients with onychodystrophies. The optimal composition and technology for producing a complex for the onychodystrophy treatment was determined in vitro. We made a literature review using the PubMed, eLibrary, Scopus, Web of Science search engines. The structure of onychodystrophies in patients of the study group was determined, clinical forms such as leukonychia, paronychia, onycholysis were diagnosed the most frequently. A significant decrease in life quality was found in 86.8% of patients. A new method of onychodystrophies treatment using the innovative medical complex, which includes an emulsion for external use and camouflage nail polish is proposed. The developed bioactive complex for patients with onychodystrophy will contribute to the rapid regeneration of the changed nail plate due to improved microcirculation and trophic innervation. More viscous and thick consistency physiological colour nail polish which does not require polymerization, will create a visual effect of a healthy nail plate, which will improve the life quality of patients with onychodystrophy.
Towards objectivity in Ostracoda species definition
Authors: Lord Alan
Published: July 2020

The problem of consistent identification of unornamented fossil ostracod taxa, especially species, is reviewed in an historical context. The solution lies in modern imaging and image storage and handling technologies combined with a careful but pragmatic (heuristic) approach to identification and taxonomy.
A novel process for cobalt and copper recovery from cobalt white alloy with high silicon
Authors: Ren Guoxing , Liu Zhihong , Pan Bing , Xiao Songwen
Published: July 2020

The cobalt white alloy, an intermediate product of cobalt smelting, is difficult to leach at atmosphere due to its corrosion-resistant structure. The current study proposed a novel process to extract Co and Cu from the cobalt white alloy with high silicon content. The process mainly involves three steps: desilication of the alloy melt through oxidation smelting using MnO-MgO-SiO2 slag, powder making of the desilication alloy melt by water atomization and atmospheric sulfuric acid leaching of the alloy powders. The results showed that 83.64% of Si in the white alloy was removed effectively by oxidizing it preferentially into the MnO-MgO-SiO2 slag. 97.99% of cobalt and 97.78% of copper were leached under optimal conditions according to: temperature of 95 °C, liquid/solid ratio of 10/1, excess of sulfuric acid of 1.3 times the stoichiometric demand, stirring rate of 1500 rpm, leaching time of 8.0 hours, and oxygen gas flow rate of 0.15 L/min. The overall recovery in this process attained 93.41% for cobalt and 94.33% for copper, separately.
Comparative study of distribution networks reconfiguration problem approaches
Authors: Moura Ana , Salvadorinho Juliana , Soares Bárbara , Cordeiro Joana
Published: July 2020

This work presents a comparative study between different resolutions approaches applied to the problem of power distribution. The main objective is to present a comparison between the various methods of resolution presented in the literature and the most used by the various authors. For this study, ninety papers that address the problem of reconfiguration of power distribution networks were analysed. The main objective is to reduce the real energy losses in the system, while several constraints regarding distribution are satisfied. The most recent papers were analysed, taking into account the approaches presented by the various authors, the formulation of the problem – namely its objective functions and constraints – the initialization methods and the stopping methods, as well as the results obtained. As such, an analysis and categorization of the various problems and approaches is presented, with the main focus being on the analysis and minimization of energy losses in 33-bus systems.
Inflammatory Cell Infiltration of Adrenals in
COVID-19
Authors: Zinserling Vsevolod A. , Semenova Natalya Yu. , Markov Alexander G. , Rybalchenko Oksana V. , Wang Jun , Rodionov Roman N. , Bornstein Stefan R.
Published: July 2020

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was originated
in November–December 2019 in Wuhan, China, and has rapidly spread
around the world causing severe health and socioeconomical damage to the
entire civilization. The key feature of coronavirus disease 2019 (COVID-19),
caused by SARS-CoV-2, is upper respiratory tract infection, which may be
complicated by bilateral pneumonia. Angiotensin converting enzyme 2 (ACE2)
has been identified as a key host factor, required for virus entry into
cells. Interestingly, ACE2 is expressed not only in the respiratory system,
but also in the other organs and systems including adrenal glands. Here we
provide the first description of the pathomorphological changes in adrenal
glands in patients with severe COVID-19 characterized by perivascular
infiltration of CD3+ and CD8+ T-lymphocytes. Due to the
central role of the adrenals in the stress response of the organism, this
finding is of potential clinical relevance, because infection with the
SARS-CoV-2 virus might critically impair adrenal function under
pathophysiological conditions.
Effects of Umbilical Cord Milking on Anemia in Preterm Infants: A Multicenter Randomized Controlled Trial
Authors: Xie Yu-jie , Xiao Jia-li , Zhu Juan-juan , Wang Yi-wen , Wang Bei , Xie Li-juan
Published: July 2020

Objective This study aimed to investigate whether umbilical cord milking (UCM) prevents and controls anemia in preterm infants, as compared with immediate cord clamping (ICC).

Study Design Pregnant women delivering at <34 weeks' gestation in four hospitals were randomly assigned to undergo UCM or ICC from July 2017 to June 2019. Hematological parameters and iron status were collected and analyzed as primary outcomes at 24 hours, 1 week, 2 weeks, and 6 months after delivery.

Results Neonates receiving UCM had significant higher levels of hemoglobin (Hb), hematocrit, and serum iron (p < 0.05). Lower prevalence of anemia and lower need for transfusions were noted in UCM group. Although UCM was associated with prolonged duration of phototherapy, the maximum levels of bilirubin were similar between two groups (p > 0.05).

Conclusion UCM is an effective intervention to help preterm infants experience less anemia with the potential to increase blood volume, as seen by higher Hb levels and more enhanced iron stores.
Using Electronic Health Record Data to Support Research and Quality Improvement: Practical Guidance from a Qualitative Investigation
Authors: Wasserman Richard C. , Ferro Daria F.
Published: July 2020

Objective The aim of the study is to identify how academic health centers (AHCs) have established infrastructures to leverage electronic health record (EHR) data to support research and quality improvement (QI).

Methods Phone interviews of 18 clinical informaticians with expertise gained over three decades at 24 AHCs were transcribed for qualitative analysis on three levels. In Level I, investigators independently used NVivo software to code and identify themes expressed in the transcripts. In Level II, investigators reexamined coded transcripts and notes and contextualized themes in the learning health system paradigm. In Level III, an informant subsample validated and supplemented findings.

Results Level I analysis yielded six key “determinants”—Institutional Relationships, Resource Availability, Data Strategy, Response to Change, Leadership Support, and Degree of Mission Alignment—which, according to local context, affect use of EHR data for research and QI. Level II analysis contextualized these determinants in a practical frame of reference, yielding a model of learning health system maturation, over-arching key concepts, and self-assessment questions to guide AHC progress toward becoming a learning health system. Level III informants validated and supplemented findings.

Discussion Drawn from the collective knowledge of experienced informatics professionals, the findings and tools described offer practical support to help clinical informaticians leverage EHR data for research and QI in AHCs.

Conclusion The learning health system model builds on the tripartite AHC mission of research, education, and patient care. AHCs must deliberately transform into learning health systems to capitalize fully on EHR data as a staple of health learning.
Nasogastric versus Orogastric Bolus Tube Feeding in Preterm Infants: Pilot Randomized Clinical Trial
Authors: Badran Ahmed Tawfik , Hashish Menna , Ali Alaa , Shokeir Mohamed , Shabaan Abd
Published: July 2020

Objective According to the most recent metanalysis, the best way to establish safe enteral feeding in preterm babies using nasogastric or orogastric tubes is still not well understood. This study aimed to determine the effects of bolus nasal tubes versus bolus orogastric tubes on the time required to reach full enteral feeding in preterm infants, as well as to compare the incidence rates of adverse events including nonintentional removal or displacement of the feeding tube, aspiration pneumonia/pneumonitis, apnea, necrotizing enterocolitis, gastric residual, and growth parameters between the studied cohort of preterm infants.

Study Design We conducted an unblinded pilot randomized clinical trial on hemodynamically stable preterm infants (>28 weeks) recruited from level 2 neonatal intensive care unit at Mansoura University Children's Hospital from June 2015 to May 2017.

Results Our study included 98 stable preterm infants with mean gestational age (orogastric group: 33.27 ± 1.08, nasogastric group: 33.32 ± 1.57) and mean birthweight (orogastric group: 1,753.3 ± 414.51, nasogastric group: 1,859.6 ± 307.05). Preterm infants who were fed via bolus nasogastric tube achieved full enteral feeding in a significantly shorter duration compared with the infants fed via bolus orogastric tube. The incidence rates of aspiration and feeding tube displacement were significantly higher in the bolus orogastric tube group compared with the bolus nasogastric tube group. There was no difference in the incidence rates of apnea, necrotizing enterocolitis, bradycardia, oxygen desaturation, and gastric residual in both groups.

Conclusion Preterm infants without any respiratory support receiving bolus nasogastric tube feeding achieved full enteral feeding significantly sooner than those receiving bolus orogastric tube feeding. Additionally, bolus nasogastric tube feeding had a lower incidence of aspiration, tube displacement, and the infants regained birthweight more quickly than those receiving orogastric tube feeding.

Key Points
Magnetostrictive particulates of Tb0.3Dy0.7Fe2 integrated into carbon fiber reinforced polymer for structural damage monitoring
Authors: Seifu Dereje , Hall Asha J. , Elbert David , McGuiggan Patricia , Myers Oliver J. , Budhani Ramesh C.
Published: July 2020

Smart materials usually are either mounted on surfaces or embedded inside; in this work, we study magnetic properties of smart materials that are integrated into the structure. Magnetostrictive particles of TbxDy1−xFe2 (x ∼ 0.3), commonly known as Terfenol-D, incorporated into carbon fiber reinforced polymers showed a 3000% enhancement in the coercive field compared to the reference pristine bulk Terfenol-D. Torque magnetometer measurements revealed a magnetic anisotropy with twofold symmetry. The lowest applied field at which a reversible torque without hysteresis occurred was ∼5.0 kOe, which yields 5 Oe anisotropic field for a carbon fiber reinforced polymer magnet. This value of the anisotropic field is confirmed using the Miyajima method. Angle dependent coercive field and saturation/remanent magnetization also confirmed the twofold symmetry of magnetization in this system. The high magnetostrictive coefficient, together with the enhanced coercive field, makes Terfenol-D integrated into carbon fiber reinforced polymers serve as an excellent candidate for in situ sensing of damage in various polymer composites under several mechanical loading conditions.
Multifrequency stimulated Raman scattering of light in a calcite single crystal
Authors: Gorelik V.S. , Skrabatun A.V. , Orlovich V.A. , Vodchits A.I.
Published: July 2020

Using pulses of multifrequency stimulated Raman scattering (SRS) in calcite, nonlinear photoluminescence in a stilbene molecular crystal is excited. When multifrequency SRS is excited by the radiation of a Nd3+: YAG laser with a wavelength of 1064 nm, eleven anti-Stokes components are observed in the visible spectrum with an average frequency shift of 1086 cm−1between them. Using the second harmonic of the Nd3+: YAG laser radiation allowed three anti-Stokes and four Stokes components to be recorded. The large spectral range of the frequency comb facilitated effective reduction in the duration and increase in the intensity of the radiation pulse of multifrequency SRS.
High-speed implementation of holographic and diffraction elements using digital micromirror devices
Authors: Evtikhiev N.N. , Zlokazov E.Yu. , Krasnov V.V. , Rodin V.G. , Starikov R.S. , Cheremkhin P.A.
Published: July 2020

We report the results of simulations and experiments on the formation of light distributions by holograms and diffraction elements displayed by digital micromirror devices. Examples of successful experiments on the implementation of optical-digital systems based on them are demonstrated.
Holographic reflective Bragg gratings of gain and their role in the operation of high-power pulsed lasers
Authors: Pogoda A.P. , Sergeev A.A. , Khakhalin I.S. , Popov E.E. , Istomina N.L. , Boreisho A.S. , Petrov V.M.
Published: July 2020

The influence of reflective Bragg gratings that are formed in an active medium due to the spatial periodic modulation of gain on the spectral properties of lasing are investigated by an example of a pulsed Nd : YAG laser. It is shown that, at a certain choice of the formation regime of reflective gratings of gain, the lasing bandwidth can be reduced by a factor of 3 – 5, with a corresponding increase in the pulse energy and significant improvement of spatial beam quality.
Synthesis, Characterization, and Theoretical Studies of cis-Dichloridobis(8-quinolinethiolato)tin(IV) and bis(8-Sulfanylquinolinium) Hexachloridostannate(IV) Derivatives
Authors: Deka Rajesh , Sarkar Arup , Singh Harkesh B. , Junk Peter C. , Turner David R. , Deacon Glen B.
Published: July 2020

The structural characterisation of bis(8-sulfanylquinolinium) hexachloridostannate(iv) (2) is reported and the variable reaction behaviour of this compound in different solvents has been explored. In particular, attempted recrystallization of 2 from chloroform and dichloromethane affords two polymorphs of cis-dichloridobis(8-quinolinethiolato)tin(iv), 3m and 3t, respectively. Attempted recrystallization of 2 from methanol gives crystals of 8,8′-dithiodiquinolinium hexachloridostannate(iv) 4. When 2 is dissolved in dimethyl sulfoxide in the presence of air, it undergoes oxidation to afford diquinolinyl-8,8′-disulfide 5. The molecular structures of the isolated compounds 2–4 are unambiguously authenticated by single crystal X-ray diffraction studies. The electronic structure properties of all the isolated compounds 2–4 are thoroughly studied by DFT calculations.
An engineered chimeric toxin that cleaves activated mutant and wild-type RAS inhibits tumor growth
Authors: Vidimar Vania , Beilhartz Greg L. , Park Minyoung , Biancucci Marco , Kieffer Matthew B. , Gius David R. , Melnyk Roman A. , Satchell Karla J. F.
Published: July 2020

Significance

RAS oncoproteins have long been considered among the most elusive drug targets in cancer research. At issue is the lack of accessible drug-binding sites and the extreme affinity for GTP. Covalent inhibitors against the KRAS G12C mutant have shown early clinical promise; however, targeting the other oncogenic RAS mutants across three RAS isoforms has proven challenging. Inhibition of activated wild-type RAS in the absence of canonicalRASmutations is also highly desirable in certain tumors. Here, we demonstrate delivery of an extremely potent pan-RAS and RAP1-cleaving enzyme in therapeutic quantities to specific receptor-bearing cells in vitro and in vivo. We aim to advance this approach to engineer the first targeted pan-RAS inhibitor for cancer therapy.
The challenges of modeling and forecasting the spread of COVID-19
Authors: Bertozzi Andrea L. , Franco Elisa , Mohler George , Short Martin B. , Sledge Daniel
Published: July 2020

Significance

The coronavirus disease 2019 (COVID-19) pandemic has placed epidemic modeling at the forefront of worldwide public policy making. Nonetheless, modeling and forecasting the spread of COVID-19 remain a challenge. Here, we present and detail three regional-scale models for forecasting and assessing the course of the pandemic. This work is intended to demonstrate the utility of parsimonious models for understanding the pandemic and to provide an accessible framework for generating policy-relevant insights into its course. We show how these models can be connected to each other and to time series data for a particular region. Capable of measuring and forecasting the impacts of social distancing, these models highlight the dangers of relaxing nonpharmaceutical public health interventions in the absence of a vaccine or antiviral therapies.
Why prefixes (almost) never participate in vowel harmony
Authors: Fábregas Antonio , Krämer Martin
Published: July 2020

One of the most common ways of morphological marking is affixation, morphemes are classified according to their position. In languages with affixal morphology, suffixes and prefixes are the most common types of affixes. Despite several proposals, it has been impossible to identify solid generalisations about the behaviour of prefixes, in opposition to suffixes. This article argues that the reason is that our traditional definitions of suffix and prefix are based on pre-theoretical, surface criteria that have been given up in other areas of linguistics: defining a morpheme as a prefix does not tell us anything about its grammatical nature, as that label does not take into consideration the structural configuration underlying the morpheme. Once the structural configuration is taken into account, solid generalisations begin to emerge. The article illustrates the advantages of this approach through a study of the interaction between vowel harmony and affixes.
French clitic climbing as periphrasis
Authors: Aguila-Multner Gabrielle , Crysmann Berthold
Published: July 2020

In this article, we propose a treatment of French clitic climbing as an instance of morphological periphrasis. In particular we reexamine the evidence in favour of argument composition and a flat VP structure with tense auxiliaries (Abeillé & Godard, 2002) and show (i) that the V (vs. VP) status of the complement does not strictly correlate with the possibility of clitic climbing, (ii) that transparency in bounded dependencies transcends the class of argument composition verbs, and (iii) that a flat VP structure complicates the treatment of modification and coordination. Adopting an approach in terms of periphrastic realisation along the lines ofBonami (2015), we provide a treatment of the climbing facts that does full justice to the limited mobility and their morphologically bound status (Miller, 1992) without having to rely on a flat VP structure. Finally, we show that the pronominalisation and extraction facts can be dealt with in a uniform fashion by way of constraints on canonical vs. non-canonical argument realisation.
Strategies for regional tourism development in Argentina. A path with new initiatives for tourism dispersal policies.
Authors: Port Natalia , Garcia Carolina Inés
Published: July 2020

This chapter analyses tourism development and policies in Argentina from an economic perspective. Recognizing that Argentina's geographical position (located away from the rest of the world and from the main outbound travel markets) produces social and economic uncertainty in the country's tourism development, the chapter focuses on tourism strategies that will stimulate regional economic growth and generate jobs while at the same time ensuring their equitable distribution throughout the country. Based on literature related to regional development and tourism dispersal, this chapter describes the current Argentine national and regional scenarios, discusses tourism policies at both national and regional/provincial levels and addresses tourism distribution from the demand and supply sides. It is argued that there are several potentialities and opportunities for a better distribution of tourism benefits for several regions of the country and that specific tourism dispersal policies and strategies at the national level can have a highly positive impact to attract visitors and benefit from tourism.
Ecotourism development in Costa Rica.
Authors: Bermúdez-Elizondo Melvin , Araúz-Beita Ileana , Arias-Navarro Adrián , Borbon-Sandí Ronald
Published: July 2020

This chapter reports on the tourism experience of Costa Rica. It reveals how, despite being a geographically small country whose land use initially was focused on agriculture and livestock, Costa Rica is a nation in which tourism has become the main source of income in the past 10 years. Specifically, this chapter documents the transition from an agricultural economy to an economy based on the services sector, where tourism (particularly ecotourism) has been positioned as the main generator of revenue. It also reveals how the vision and conservation efforts made by Costa Rica have allowed the country to maintain 25% of its territory under some form of environmental protection, with around 70% of its international tourists visiting one protected area. It is recognized that, although tourism has experienced a sustained growth and greater economic impact in the country, the social benefits in local communities are very limited.
The challenges of natural and cultural heritages of Galapagos and Quito, Ecuador.
Authors: Muñoz-Barriga Andrea , Maldonado Pérez Gabriela
Published: July 2020

This chapter analyses tourism impacts at two UNESCO World Heritage Sites in Ecuador. Recognizing that tourism is a marginal activity in general in comparison with other mature destinations in Latin America, the Galapagos and Quito are analysed for their distinctive characteristics, tourism activity and impacts, and institutional frameworks in order to identify strategic actions for ameliorating negative tourism impacts and promoting both destinations as heritage sites. It is revealed that tourism development in these iconic destinations has brought not only benefits but also several concerns related to the country's natural and cultural diversity preservation and that, as a consequence, an increase in the number of tourists is not desirable as it could jeopardize the conservation of its flora and fauna and could lead to the degradation of historical buildings. Long-term policies and control and regulation mechanisms for the conservation and preservation of these heritage sites are thus considered as practical recommendations.
Ecuador and Panama: lifestyle mobilities, the golden years and the quest for Paradise.
Authors: Montero Carla Guerrón
Published: July 2020

This chapter examines tourism development experiences in both Ecuador and Panama. Based on ethnographic research, it discusses in particular how lifestyle mobilities are experienced in these two countries, which have both become 'best places to retire' locations for North Americans and Western Europeans in the past decade. Both countries have temperate climates, a dollar economy that affords relatively low living costs, abundant natural beauty and diverse populations that represent Latin America's multicultural history, making them ideal for lifestyle migration. This chapter reveals positive and negative outcomes of significance in tourism management and public policy design derived from governmental policies that give privilege to residential tourism, and it describes the important social consequences of lifestyle migration for the host communities of both countries.
Forecasting the outcomes of sports events: A review
Authors: Wunderlich Fabian , Memmert Daniel
Published: July 2020

In the scientific community a large literature on sports forecasting exists, covering a wide range of different sports, methods and research questions. At the same time a lack of general literature such as reviews or meta‐analyses on aspects of sports forecasting can be attested, partly attributable to characteristics of forecasting in sports that make it difficult to present through systematic approaches. The present study contributes to filling this gap by providing a narrative review about forecasting related to the outcomes of sports events. An overview about relevant topics in forecasting the outcomes of sports events is presented, a basic methodology is discussed and a categorization of methods is introduced. Having a specific focus on forecasting from ratings, we shed light on the difference between systematic and unsystematic effects influencing the outcomes of sports events. Finally an outlook on the expected impact of the increasing amount and complexity of available data on future sports forecasting research is presented. The present review can serve as a valuable starting point for researchers aiming at the investigation of sports‐related forecasts, both helping to find appropriate methods and classify their work in the context of the state of research.
A novel rotation speed uniformity evaluation method for the rotary laser scanning measurement system
Authors: Zhang Zhenyu , Ren Yongjie , Yang Linghui , Lin Jiarui , Shi Shendong , Zhu Jigui
Published: July 2020

For rotary laser scanning measurement systems, the rotation speed uniformity of the measurement part directly affects the system’s measurement accuracy. To monitor the details of the rotation speed changes within a cycle, this paper proposes a rotation speed uniformity evaluation method for rotary laser scanning measurement systems, which can both detect the rotation speed change within a cycle and obtain the speed change with the angular position. This method is expounded in detail, including the calibration of the rotary encoder gratings, the acquisition of the real-time rotation speed change sequence, and the post-processing of the rotation speed change sequence. The feasibility of the novel processing method is verified by comparison experiments: the novel method is compared with a speed signal processing method based on measuring of rotational periodicity to verify the feasibility. The measurement accuracy of the novel method was analyzed based on the theory of uncertainty propagation. Based on the verification results, the novel method was utilized to evaluate the speed uniformity of the transmitter at different speeds and analyzes the influence of rotation speed uniformity on the angular accuracy of the system, and the experimental results reveal that the novel method is able to detect the fluctuation of the rotation speed within a circle at different speeds, and for the transmitter, the higher working speeds has less relative speed changes and less angle measurement errors.
Thermal stability of magnetron sputtering Ge–Ga–S films*
Authors: Niu Lei , Chen Yimin , Shen Xiang , Xu Tiefeng
Published: July 2020

Ge–Ga–S thin films were deposited by magnetron sputtering with mean coordination number (MCN) ranging from 2.46 to 2.94. The physical properties of the Ge–Ga–S films, including optical band gap, refractive index, and thickness, vary with the time of heat treatment. Based on the analysis of the topology model, it is concluded that the Ge–Ga–S thin films with components close to the stoichiometric ratio can form the most Ga–S bonds and Ga–S bonds, and the physical properties of the Ge27.3Ga6.3S66.3 (MCN = 2.62) film are the most stable. This is an important reference for thin film photonic devices.
Perspective for aggregation-induced delayed fluorescence mechanism: A QM/MM study*
Authors: Liu Jie , Fan Jianzhong , Zhang Kai , Zhang Yuchen , Wang Chuan-Kui , Lin Lili
Published: July 2020

To enhance the potential application of thermally activated delayed fluorescence (TADF) molecular materials, new functions are gradually cooperated to the TADF molecules. Aggregation induced emission can effectively solve the fluorescence quenching problem for TADF molecules in solid phase, thus aggregation-induced delayed fluorescence (AIDF) molecules were recently focused. Nevertheless, their luminescent mechanisms are not clear enough. In this work, excited state properties of an AIDF molecule DMF-BP-DMAC [reported in Chemistry–An Asian Journal
14 828 (2019)] are theoretically studied in tetrahydrofuran (THF) and solid phase. For consideration of surrounding environment, the polarizable continuum method (PCM) and the combined quantum mechanics and molecular mechanics (QM/MM) method were applied for solvent and solid phase, respectively. Due to the increase of the transition dipole moment and decrease of the energy difference between the first single excited state (S1) and the ground state (S0), the radiative rate is increased by about 2 orders of magnitude in solid phase. The energy dissipation of the non-radiative process from S1 to S0 is mainly contributed by low-frequency vibrational modes in solvent, and they can be effectively suppressed in aggregation, which may lead to a slow non-radiation process in solid phase. Both factors would induce enhanced luminescence efficiency of DMF-BP-DMAC in solid phase. Meanwhile, the small energy gap between S1 and triplet excited states results in high reverse intersystem crossing (RISC) rates in both solvent and solid phase. Therefore, TADF is confirmed in both phases. Aggregation significantly influences both the ISC and RISC processes and more RISC channels are involved in solid state. The enhanced delayed fluorescence should be induced by both the enhanced fluorescent efficiency and ISC efficiency. Our calculation provides a reasonable explanation for experimental measurements and helps one to better understand the luminescence mechanism of AIDF molecules.
An improved global-direction stencil based on the face-area-weighted centroid for the gradient reconstruction of unstructured finite volume methods*
Authors: Kong Ling-Fa , Dong Yi-Dao , Liu Wei , Zhang Huai-Bao
Published: July 2020

The accuracy of unstructured finite volume methods is greatly influenced by the gradient reconstruction, for which the stencil selection plays a critical role. Compared with the commonly used face-neighbor and vertex-neighbor stencils, the global-direction stencil is independent of the mesh topology, and characteristics of the flow field can be well reflected by this novel stencil. However, for a high-aspect-ratio triangular grid, the grid skewness is evident, which is one of the most important grid-quality measures known to affect the accuracy and stability of finite volume solvers. On this basis and inspired by an approach of using face-area-weighted centroid to reduce the grid skewness, we explore a method by combining the global-direction stencil and face-area-weighted centroid on high-aspect-ratio triangular grids, so as to improve the computational accuracy. Four representative numerical cases are simulated on high-aspect-ratio triangular grids to examine the validity of the improved global-direction stencil. Results illustrate that errors of this improved methods are the lowest among all methods we tested, and in high-mach-number flow, with the increase of cell aspect ratio, the improved global-direction stencil always has a better stability than commonly used face-neighbor and vertex-neighbor stencils. Therefore, the computational accuracy as well as stability is greatly improved, and superiorities of this novel method are verified.
Sintering reaction and microstructure of MAl (M = Ni, Fe, and Mg) nanoparticles through molecular dynamics simulation*
Authors: Zhang Yuwen , Deng Yonghe , Zeng Qingfeng , Wen Dadong , Zhao Heping , Gao Ming , Dai Xiongying , Wu Anru
Published: July 2020

The sintering–alloying processes of nickel (Ni), iron (Fe), and magnesium (Mg) with aluminum (Al) nanoparticles were studied by molecular dynamics simulation with the analytic embedded-atom model (AEAM) potential. Potential energy, mean heterogeneous coordination number

N
A
B

, and surface atomic number N
surf–A were used to monitor the sintering–reaction processes. The effects of surface segregation, heat of formation, and melting point on the sintering–alloying processes were discussed. Results revealed that sintering proceeded in two stages. First, atoms with low surface energy diffused onto the surface of atoms with high surface energy; second, metal atoms diffused with one another with increased system temperature to a threshold value. Under the same initial conditions, the sintering reaction rate of the three systems increased in the order MgAl < FeAl < NiAl. Depending on the initial reaction temperature, the final core–shell (FeAl and MgAl) and alloyed (NiAl and FeAl) nanoconfigurations can be observed.
Short-wavelength infrared InAs/GaSb superlattice hole avalanche photodiode*
Authors: Liu Jia-Feng , Zhang Ning-Tao , Teng Yan , Hao Xiu-Jun , Zhao Yu , Chen Ying , Zhu He , Zhu Hong , Wu Qi-Hua , Li Xin , Chen Bai-Le , Huang Yong
Published: July 2020

We demonstrate two short-wavelength infrared avalanche photodiodes based on InAs/GaSb superlattice grown by metal-organic chemical vapor deposition. The difference between the two devices, namely, p+n−n+ and p+nn−n+, is that the p+nn−n+ device possesses an additional middle-doped layer to separate the multiplication region from the absorption region. By properly controlling the electric field distribution in the p+nn−n+ device, an electric field of 906 kV/cm has been achieved, which is 2.6 times higher than that in the p+n−n+ device. At a reverse bias of –0.1 V at 77 K, both devices show a 100% cut-off wavelength of 2.25 μm. The p+n−n+ and p+nn−n+ show a dark current density of 1.5 × 10−7 A/cm2 and 1.8 × 10−8 A/cm2, and a peak responsivity about 0.35 A/W and 0.40 A/W at 1.5 μm, respectively. A maximum multiplication gain of 55 is achieved in the p+nn−n+ device while the value is only less than 2 in the p+n−n+ device. Exponential nature of the gain characteristic as a function of reverse bias confirms a single carrier hole dominated impact ionization.
Thermoelectric properties of orthorhombic silicon allotrope Si (oP32) from first-principles calculations*
Authors: Zhang Pei , Ouyang Tao , Tang Chao , He Chao-Yu , Li Jin , Zhang Chun-Xiao , Zhong Jian-Xin
Published: July 2020

The diamond-like cubic silicon (d-Si) is widely used in modern electronics and solar cell industries. However, it is not an optimal candidate for thermoelectric application due to its high lattice thermal conductivity. Si (oP32) is a recently predicted orthorhombic silicon allotrope, whose total energy is close to that of d-Si. Using first-principles calculations and Boltzmann transport theory, we systematically investigate the thermoelectric properties of Si (oP32). The lower phonon thermal conductivity and higher power factor are obtained in Si (oP32) than those in diamond silicon. The low phonon thermal conductivity (33.77 W/mK at 300 K) is mainly due to the reduction of the phonon group velocity and enhancement of phonon–phonon scattering (including scattering phase space and strength). Meanwhile, the results also show that the thermoelectric performance along the zz lattice direction is better than that along the xx and yy lattice directions, and the figure of merit (700 K) along the zz lattice direction could approach to 2.45 and 1.75 for p-type and n-type Si (oP32), respectively. The values are much higher than those of d-Si (about 0.06)) and Si24 (0.6), indicating that the Si (oP32) is a promising candidate for thermoelectric applications. Our theoretical studies shed light on the thermoelectric properties of Si (oP32) and could stimulate further experimental studies.
Research of influence of the additional electrode on Hall thruster plume by particle-in-cell simulation*
Authors: Cao Xi-Feng , Liu Hui , Yu Da-Ren
Published: July 2020

Hall thruster is an electric propulsion device for attitude control and position maintenance of satellites. The discharge process of Hall thruster will produce divergent plume. The plume will cause erosion, static electricity, and other interference to the main components, such as solar sailboard, satellite body, and thruster. Therefore, reducing the divergence of the plume is an important content in the research of thruster plume. The additional electrode to the plume area is a way to reduce the divergence angle of the plume, but there are few related studies. This paper uses the particle-in-cell (PIC) simulation method to simulate the effect of the additional electrode on the discharge of the Hall thruster, and further explains the effect mechanism of the additional electrode on parameters such as the electric field and plume divergence angle. The simulation results show that the existence of the additional electrode can enhance the potential near the additional position. The increase of the potential can effectively suppress the radial diffusion of ions, and effectively reduce the plume divergence angle. The simulation results show that when the additional electrode is 30 V, the half plume divergence angle can be reduced by 18.21%. However, the existence of additional electric electrode can also enhance the ion bombardment on the magnetic pole. The additional electrode is relatively outside, the plume divergence angle is relatively small, and it can avoid excessive ion bombardment on the magnetic pole. The research work of this paper can provide a reference for the beam design of Hall thruster.
Mobile Based Geographic Information System for mapping and data collection Towards 4.0 Industry
Authors: Bahtiar Hariman , Kerta Wijaya L.
Published: July 2020

Geographic Information System Technology makes it easier for us to manage geo-referenced information data or mapping the location of an area that is connected to the database. Nahdlatul Wathan is one of the largest organizations in West Nusa Tenggara, where there has been rapid development from year to year, especially in the field of education. The number of Islamic schools (madrasas) under the Nahdlatul Wathan organization is increasing every year. But until now, the location (geographical location) of each school is still not well recorded and mapped. Therefore, we need a geographic information system that can be used for the process of mapping and data collection of schools under the Nahdlatul Wathan organization that can help the management of Nahdlatul Wathan and each Islamic school and community to find out the location. from each school, which can be accessed quickly and precisely.
IOT Base Household Equipment Control Using Arduino and Smartphone
Authors: Ahmad Ramli , Candra P Baiq Andriska
Published: July 2020

Due to the rapid development of mobile technology, especially android smartphones as a communication device and smart phone has improved a lot of developments, such as remote control that can control electronic devices. Indirectly, the use of a remote control can reduce the user’s task in handling electronic equipment. This research aims to build a control system that can control electronic devices using Arduino ESP and Android based on Internet of Things (IOT). The construction of this system is expected to make it is easier for users to control electronic devices remotely. Users only provide voice commands via Google Assistant on Android, which was built to make commands to turn on or turn off electronic devices by utilizing an internet connection. The tests on the system have been done and the result show that the system can work well to turn on and turn off electronic devices. The system has a delay of (3 seconds) for each command sent by the user via an Android smartphone.
Application of Expert System with Web-Based Forward Chaining Method in Diagnosing Corn Plant Disease
Authors: Saiful Muhammad , Muliawan Nur Amri
Published: July 2020

Corn plants are crops in agriculture which are widely cultivated, especially in the Jerowaru area. The empowerment of corn plants is often constrained by disease. Diseases in maize plants are caused by fungi, bacteria, viruses, soil conditions, and weather conditions. Diseases that attack corn plants can result in decreased productivity of corn plants. On the other hand, the limited number of agricultural extension workers makes farmers unable to quickly consult, therefore it is necessary to create a system that can provide information, make decisions and provide solutions regarding web-based corn plant diseases can diagnose corn plant diseases based on symptoms experienced corn plant. This expert system is designed using the Forward Chaining method consisting of several stages, namely, the stages of assessment, knowledge acquisition, design, and testing. Based on the results of tests conducted, this method can provide solutions in dealing with problems related to corn diseases and pests.
The Influence of Using Video Media on Basic Movement Skills Lay-Up Shoot Basketball
Authors: Nopiana Rina , Akbar M. Falahil , Husni Tamim Muhammad
Published: July 2020

This study aimed to know the effect of the use of video media on basic motion skills basketball extracurricular lay-up shoot of high school students at senior high school 01 in the school year 2018/2019. The research used in this study was quantitative research with research design which was experimentation. To determine the sampling in this study used saturated sampling technique which was using all students who take part in basketball extracurricular activities at SMAN 01 Suela. The samples in this study were 15 students participating in basketball extracurricular activity at SMAN 01 Suela in the school year 2018/2019. Data collection techniques used in this research is pre-test and post-test one group. From the calculation results showed that the t-count value was greater than t-table (5.58> 1.761) at a significance level of 5% indicating that there was an influence of the use of video media on the basic motion ability of basketball lay-up shoot on SMAN 01 Suela in the school year 2018/2019. This showed Ha: accepted and Ho: rejected.
Red blood cells and white blood cells detection by image processing
Authors: Rahadi Irwan , Choodoung Meechoke , Choodoung Arunsri
Published: July 2020

The common method of red and white blood cells identification and counting consider the manual processes on microscope which is arranged by the laboratory’s technician with their own experience. In this research, we will develop a computer program to detect and identify the proposed objects based on their pattern. The proposed objects are Red Blood Cells (RBCs), and White Blood Cells (WBCs). For blood cells identification and classification, an idea of Viola and Jones will be followed. Adaboost (adaptive boosting) method will be applied to increase the accuracy of the error of learning algorithm. The output of the proposed program shows that all the types of cells mentioned can be detected and classify effectively by showing the number and time spent of cells detected.
Comparison Of Pso-Based Naive Bayes And Naive Bayes Algorithm In Determining The Feasibility Of Bumdes Credit
Authors: Putra Yupi Kuspandi , Fathurrahman  , Sadali Muhamad
Published: July 2020

In analyzing a credit, sometimes an analysis performs an inaccurate analysis so that some customers are less able to make credit installment payments, resulting in less smooth or even bad loans. From these problems, researchers conducted a credit analysis using computerized techniques using RapidMiner software in data processing. The right data processing technique to use is classification. One method of data mining classification is the Naive Bayes algorithm. Researchers use weighting by implementing Particle Swarm Optimization (PSO) for attribute selection to improve the accuracy of Naive Bayes. After testing with two models namely Naive Bayes algorithm and Naive Bayes based on PSO, the results obtained are for the Naive Bayes algorithm with an accuracy value of 93.24%, while the Naive Bayes algorithm based on particle swarm optimization models produces a higher accuracy value of 98.16% compared to the Naive Bayes algorithm model. From these results, the difference between the two models is 4.92%. Then for the results of using the ROC curve for both models, for the Naive Bayes algorithm, the AUC value is 0.939 with an Excellent Classification diagnostic level, and for the Naive Bayes algorithm model based on particle swarm optimization, the AUC value is 0.977 with an Excellent Classification diagnostic level. From the evaluation of the ROC curve, it is seen that the Naive Bayes model based on particle swarm optimization is higher when compared to the Naive Bayes algorithm. From the results of the AUC, the difference between the two models is 0.038.
M-Absence : Analysis and Design using Unified Modelling Language (UML)
Authors: Anjani Dewi , Hilaliyah Hilda , Novianti Desi
Published: July 2020

The development of cellular technology is very fast; this has led to technological advances in all fields where one of them is education. E-absent is an Android-based technology that serves to help student guardians report or notify student absence to the teacher and enter the necessary documents into the system. Then the teacher will send the subject matter and lesson assignments to students when students are absent, so students do not miss the lesson. This paper discusses system analysis and design using the Unified Modelling Language (UML), which makes it easier to describe the system as a whole. And the results of this study are an e-absence model that fits the needs of the school.