bluuebunny/crossref_metadata_2025 huggingface dataset:
Linear Stability of Momentum Boundary Layer Flow and Heat Transfer Over a Moving Wedge
Authors: Kudenatti Ramesh B. , Misbah Noor E. , Bharathi M. C.
Published: March 2020

This paper studies the linear stability of the unsteady boundary-layer flow and heat transfer over a moving wedge. Both mainstream flow outside the boundary layer and the wedge velocities are approximated by the power of the distance along the wedge wall. In a similar manner, the temperature of the wedge is approximated by the power of the distance that leads to a wall exponent temperature parameter. The governing boundary layer equations admit a class of self-similar solutions under these approximations. The Chebyshev collocation and shooting methods are utilized to predict the upper and lower branch solutions for various parameters. For these two solutions, the velocity, temperature profiles, wall shear-stress, and temperature gradient are entirely different and need to be assessed for their stability as to which of these solutions is practically realizable. It is shown that algebraically growing steady solutions do exist and their effects are significant in the unsteady context. The resulting eigenvalue problem determines whether or not the steady solutions are stable. There are interesting results that are linked to bypass an important class of boundary layer flow and heat transfer. The hydrodynamics behind these results are discussed in some detail.
Progress Toward Roll Processing of Solar Reflective Material
Authors: Smilgys Russell V. , Wallace Steven P. , Kennedy Cheryl E.
Published: March 2020

The goal of this work is to demonstrate that high performance solar reflective material can be produced in a roll format using vacuum deposition techniques. The material consists of a multilayer thin film stack on a substrate. The essential feature of the film stack is an alumina film several microns thick deposited over a silver film. The alumina film is deposited under high vacuum using a physical vapor deposition technique called ion beam assisted deposition (IBAD). The alumina film is optically transparent, scratch resistant, and durable. Its purpose is to protect the silver film and maintain high optical reflectance.

Work on this reflective material began five years ago. Samples were produced on polyester substrates by batch coating. Those samples showed excellent durability in accelerated testing at the National Renewable Energy Laboratory (NREL) in Golden Colorado. The principal limitation to commercialization of the process was a low alumina deposition rate. Over the past three years the alumina deposition rate has been increased from 1 nm/s to 20 nm/s.

The next step is to produce material in a roll format. A roll coater has been built to process 30.48-cm wide rolls of solar reflective material. A steel strip with a highly specular surface finish will be used as the web material. The advantage of this material compared to polyester is that it withstands a higher process temperature and lowers final product installation costs. A major technical challenge will be to reproduce high reflector durability in a continuous, high rate process.
Optimization of Korean Crop Storage Insulation Systems
Authors: Yoon JongHo , Lee Euy-Joon , Krarti Moncef
Published: March 2020

With the increasing concerns with the quality and the safety of foods, several standards and guidelines have been developed to improve the design, construction, and operation of storage warehouses. Several cool storage buildings have been constructed in Korea during the last decade. However, there are no specific standards or guidelines for energy use reduction in refrigerated structures. The main objective of this study to determine the impact of various insulation systems on the total cooling load of the cool storage structures with particular consideration given to the product thermal mass effect to find optimal insulation thickness for each envelope component for various climatic locations in Korea. An energy analysis model was developed using the DOE-2.1E program and over 3500 energy simulations were performed. To determine the optimal configuration for die storage building insulation system, life-cycle cost analysis was conducted. The selection of optimal insulation configuration for each climatic location is based on various criteria including those of crop storage owners and of national energy conservation policy. The results presented in this paper provide easy-to-use design guidelines to select optimal insulation thickness for crop storage facility in Korea.
Dehumidification Through Indirect Nighttime Ventilation
Authors: Abaza Hussein , Beliveau Yvan , Jones Jim
Published: March 2020

Natural ventilation is an important passive cooling strategy. Using cool night air can cool the building structure and lower air conditions energy consumption. However, there are obstacles in using this cooling strategy, including high relative humidity, pollution, limitations in the thermal storage of the building, and low nighttime air temperature. This paper investigates energy savings by indirect ventilation to pre-cool buildings and reduces humidity. The nighttime ventilation strategy is based on optimizing the use of direct and indirect natural ventilation through an air-to-air heat exchanger. This strategy has been tested at the Beliveau House in Blacksburg, Virginia. Simulation results suggest that the indirect ventilation strategy at the Beliveau House reduces inside relative humidity on hot humid summer days by 20%, and the total summer cooling load by 38% when compared to the existing condition.
Ground-Coupled Heat and Moisture Transfer From Buildings: Part 2 — Application
Authors: Deru Michael P. , Kirkpatrick Allan T.
Published: March 2020

In this paper the effects of moisture on the heat transfer from two basic types of building foundations, a slab-on-grade and a basement, are examined. A two-dimensional finite element heat and moisture transfer program is used to show the effects of precipitation, soil type, foundation insulation, water table depth, and freezing on the heat transfer from the building foundation. Comparisons are made with a simple heat conduction model to illustrate the dependency of the soil thermal conductivity on moisture content.
Hybrid Lighting: Designing an Energy-Saving Strategy for Bioregenerative Space Life Support
Authors: Cuello Joel L.
Published: March 2020

The objective of this paper was to provide an overview of current ground-based efforts in the design and development of hybrid lighting systems, combining solar irradiance and electric lighting, to effect reduced electrical power demand for growing plants in a bioregenerative life support system (BLSS) for future space applications on the Moon or Mars. Two experimental Hybrid Solar and Artificial Lighting (HYSAL) systems have been developed: one employing xenon-metal halide (XMH) lamps and the other adopting light-emitting diodes (LEDs) as the electric-lighting components, and both using a mirror-based, fiberoptic-based solar collection system. The results showed that both HYSAL systems provided acceptable spectral quality and lighting uniformity. The apparent electrical conversion efficiency of the HYSAL system with LEDs, however, exceeded that of the HYSAL system with XMH by five-fold. Preliminary simulations of a Martian BLSS indicated that the lighting power required for plant production could be supplemented by the available extraterrestrial solar irradiance by as much as 50%. The use of solar stationary orbits over Mars for an orbiting Martian BLSS to reduce the required electrical power was also suggested.
Roof Integrated Solar Absorber: The Measured Performance of “Invisible” Solar Collectors
Authors: Colon Carlos J. , Merrigan Tim
Published: March 2020

The Florida Solar Energy Center (FSEC), with the support of the National Renewable Energy Laboratory (NREL), has investigated the thermal performance of solar absorbers which are an integral yet indistinguishable part of a building’s roof. The first roof-integrated solar absorber (RISA) system was retrofitted into FSEC’S Flexible Roof Facility in Cocoa, Florida in September 1998. This “proof-of-concept” system uses the asphalt shingle roof surface and the plywood decking under the shingles as an unglazed solar absorber. The absorbed solar heat is then transferred to water that is circulated from a storage tank through polymer tubing attached to the underside of the roof decking. Data collected on this direct 3.9 m2 (42 ft2) solar system for a period of 12 months indicates that it was able to provide an average of 3.4 kWh per day of hot water energy to the storage tank under a 242 liters (64 gal) per day load. The RISA system’s average annual solar conversion efficiency was also determined to be 8 percent, with daily efficiencies reaching a maximum of 13 percent. In addition, a thermal performance equation has been determined to characterize the Phase 1 RISA system’s year-long efficiency under various ambient temperature, insolation, and wind speed conditions.

As a follow-on to the proof-of-concept phase, two prototypes of approximately 4.5 m2 (48 ft2) surface area were constructed and submitted for FSEC thermal performance testing. These Phase 2 RISA prototypes differ in both roof construction and the position of the polymer tubing. One prototype is similar to the “proof-of-concept” RISA system as it employs an asphalt shingle roof surface and has the tubing mounted on the underside of the plywood decking. The second RISA prototype uses metal roofing panels over a plywood substrate and places the polymer tubing between the plywood decking and the metal roofing. Both prototypes were tested according to ASHRAE Standard 93 for determining the thermal performance of solar collectors. From performance data measured both outdoors and indoors using a solar Simulator, FR(ταe)’s were determined to be approximately 18% and 33% for the asphalt shingle and metal roof RISA prototypes, respectively. In addition, the coefficients of linear and second-order efficiency equations were also determined at various wind speeds. Finally, an FSEC thermal performance rating was calculated at the low and intermediate temperature levels. In summary, this paper is a first look at the thermal performance results for these “invisible” solar absorbers that use the actual roof surface of a building for solar heat collection.
Experiences With Using Solar Photovoltaics to Heat Domestic Water
Authors: Dougherty Brian P. , Fanney A. Hunter
Published: March 2020

The solar photovoltaic (PV) industry continues to make progress in increasing the efficiency while reducing the manufacturing costs of PV cells. Economies of scale are being realized as manufacturers expand their production capabilities. Products are commercially available that integrate photovoltaic cells within building façade, fenestration, and roofing components. Legislation and incentive programs by government and commercial entities are supporting both reduced first costs and greater rates of return. The combination of factors support improved cost-effectiveness. As this trend continues, more options for using PV become possible. One such application is a stand-alone, PV-direct, solar water heating application.

Solar water heating can be effectively accomplished by directly using the DC power production from solar photovoltaic modules. A simple controller having multiple power relays connects the PV modules with different combinations of in-tank resistive elements. The controller actively changes the resistive combination so that the photovoltaic modules generate power at or near their maximum output.

The technology, which has been patented and licensed, is applicable to configurations that use a single water heater and to two water heaters that are piped in series. Prototypes using both tank configurations have been in operation at four field sites. This paper emphasizes the single-tank application and the field results from installations in Maryland and Florida.
Field Tests of a PV-Powered Air Monitoring System
Authors: Sanidad L. , Baghzouz Y. , Boehm R. , Hodge Earl
Published: March 2020

A compact stand-alone PV power system was recently designed and built to run an air sampler for environmental monitoring at the Nevada Test Site. This paper presents an overview of the system design and analysis of some of the recorded daily cycles of various power flows during the summer period. The system long-term performance during both high and low solar resource periods is simulated with the computer code PVFORM using historical weather data.
Recommendations for Maximizing Battery Life in Photovoltaic Systems: A Review of Lessons Learned
Authors: Dunlop James P. , Farhi Brian N.
Published: March 2020

This report contains notes, observations and recommendations about the use of batteries in small stand-alone photovoltaic (PV) systems. The conclusions of this work are based on the results of more than a decade’s worth of battery testing at the Florida Solar Energy Center and related work with Sandia National Laboratories, the PV industry and user groups. The most critical findings were the relationship between battery state-of-charge and battery life and the importance of an adequate PV array-to-load ratio.
Photovoltaic Phenomena in Thin Film ZnTe-CdSe Heterojunctions
Authors: Focsha Alexandru , Gashin Petru , Simashkevich Alexei
Published: March 2020

Thin layer ZnTe-CdSe heterojunctions were produced by vapor phase epitaxial growth of ZnTe and CdSe layers on mica and single-crystal ZnSe substrates. These heterojunctions photosensitivity covers the wavelength region of 0.56–0.85 μm. The shape of photosensitivity spectral dependence of ZnTe-CdSe heterojunction depends on the components thickness and their doping level. Thin layer ZnTe-CdSe epitaxial heterojunction parameters under illumination of 80 mW/cm2 (AM1.5) are: FF=0.53, Uoc=0.72V, Isc=14.8 mA/cm2, efficiency η=7.1%. Thin film polycrystalline ZnTe-CdSe heterojunctions having the efficiency η=4.3%, Uoc=0.54 V, Isc=10.6 mA/cm2 were fabricated by using As or Cu doped ZnTe layers and In doped CdSe layers produced by HWT.
TRNSYS Modeling of the SEGS VI Parabolic Trough Solar Electric Generating System
Authors: Jones Scott A. , Pitz-Paal Robert , Schwarzboezl Peter , Blair Nathan , Cable Robert
Published: March 2020

A detailed performance model of the 30 MWe SEGS VI parabolic trough plant was created in the TRNSYS simulation environment using the Solar Thermal Electric Component model library. Both solar and power cycle performance were modeled, but natural gas-fired hybrid operation was not. Good agreement between model predictions and plant measurements was found, with errors usually less than 10%, and transient effects such as startup, shutdown, and cloud response were adequately modeled. While the model could be improved, it demonstrates the capability to perform detailed analysis and is useful for such things as evaluating proposed trough storage systems.
Novel Ionic Liquid Thermal Storage for Solar Thermal Electric Power Systems
Authors: Wu Banqiu , Reddy Ramana G. , Rogers Robin D.
Published: March 2020

Feasibility of ionic liquids as liquid thermal storage media and heat transfer fluids in a solar thermal power plant was investigated. Many ionic liquids such as [C4min][PF6], [C8mim][PF6], [C4min][bistrifluromethane sulflonimide], [C4min][BF4], [C8mim][BF4], and [C4min][bistrifluromethane sulflonimide] were synthesized and characterized using thermogravimetric analysis (TGA), differential scanning calorimeter (DSC), nuclear magnetic resonance (NMR), viscometry, and some other methods. Properties such as decomposition temperature, melting point, viscosity, density, heat capacity, and thermal expansion coefficient were measured. The calculated storage density for [C8mim][PF6] is 378 MJ/m3 when the inlet and outlet field temperatures are 210°C and 390°C. For a single ionic liquid, [C4mim][BF4], the liquid temperature range is from −75°C to 459°C. It is found that ionic liquids have advantages of high density, wide liquid temperature range, low viscosity, high chemical stability, non-volatility, high heat capacity, and high storage density. Based on our experimental results, it is concluded that ionic liquids could be excellent liquid thermal storage media and heat transfer fluids in solar thermal power plant.
Heat, Mass and Fluid Flow in a Solar Reactor for Fullerene Synthesis
Authors: Guillard Tony , Flamant Gilles , Laplaze Daniel
Published: March 2020

A 2 kW solar furnace was used to vaporize a graphite target for fullerene synthesis. Tests were performed in a wide range of vaporization rates (0.1–4 g/h), under variable pressure and argon flow rate. Experimental results are interpreted with numerical simulation to define key parameters for large-scale synthesis of fullerenes with solar energy. We demonstrate that the vaporization process is controlled by diffusion in the temperature and pressure ranges 3000–3700 K and 70–250 hPa respectively.

Experimental data and numerical simulation suggest that in the solar reactor, fullerene yield is governed by the dilution of carbon vapor in argon and by the temperature gradient in the cooling zone. Criteria for both parameters are suggested. Consequently, these data, combined with the numerical model accounting for heat, mass and fluid flow inside the reactor, may be used for the design of large-scale solar process.
Seasonally-invariant head wave speed extracted from ocean noise cross-correlation
Authors: Yang Xishan , Li Fenghua , Zhang Bo , Luo Wenyu
Published: March 2020

Ambient noise was recorded continuously for 9 months by two horizontal arrays deployed in shallow water with a horizontal separation of approximately 0.5 km. Stable empirical Green's functions (EGFs) were extracted from ambient noise correlations between the two arrays. The EGFs have three distinct envelopes which correspond to the head waves, direct waves, and surface-reflected waves. The arrival time of the head wave was almost constant with season. Corresponding simulations were carried out, and implied that the relatively small penetration depth of heat flow is the main reason for the seasonally-invariant head wave speed.
Exploring the Influence of Stimulus Events: A Case Study of Undergraduate Student Internships
Authors: McClean Cole , Odio Michael A. , Kerwin Shannon
Published: March 2020

Internships are crucial in many sport management students’ paths to the sport industry. This mixed-methods case study sought to understand the nature of events occurring in sport management internships and the impact on two outcomes: student career decision making and subjective well-being. Pre–post internship surveys (n = 23) and follow-up interviews (n = 21) identified stimulus events, if intern expectations were met, and if career intentions or subjective well-being were shifted. For participants, stimulus events involved different aspects of the internship (e.g., tasks, supervisor, social interactions, inclusivity, and the environment), and the perceptions of outcomes related to internships varied. In line with image theory, participants followed four impact pathways, with the focus on stimulus events influencing career intentions and then well-being as a result, or conversely well-being then career intentions. The findings have important theoretical and practical implications for both sport management educators and organizational supervisors that can help ensure mutually beneficial experiences for all parties involved.
“I Just Want to Be Left Alone”: Novel Sociological Insights Into Dramaturgical Demands on Professional Athletes
Authors: Roderick Martin , Allen-Collinson Jacquelyn
Published: March 2020

To date, no sociological studies of professional athletes have investigated the lived experiences of sportspeople in highly publicly visible occupations that provide relatively few opportunities for backstage relaxation from role demands. Drawing on findings from a British Academy-funded project examining high-profile sports workers and employing Goffman’s dramaturgical insights, this article provides a novel examination of high-profile athletes who work in highly publicly visible contexts. This working context can render them “open” persons in interactional situations. To explore this sociologically significant occupational domain, interviews were conducted with 26 U.K.-based professional athletes (females and males) from seven different sports. For these athletes, dramaturgical demands were found to be relentless and unremitting, as backstage regions proved so challenging to access.
Timing matters in combination therapy
Authors: Ferrarelli Leslie K.
Published: March 2020

Subsequent, not concurrent, treatment with CDK4/6 inhibitors improves the efficacy of chemotherapy.
Early Paleocene Magnetostratigraphy and Revised Biostratigraphy of the Ojo Alamo Sandstone and Lower Nacimiento Formation, San Juan Basin, New Mexico, USA
Authors: Flynn Andrew G. , Davis Adam J. , Williamson Thomas E. , Heizler Matthew , Fenley C. William , Leslie Caitlin E. , Secord Ross , Brusatte Stephen L. , Peppe Daniel J.
Published: March 2020

The lower Paleocene Ojo Alamo Sandstone and Nacimiento Formation from the San Juan Basin (SJB) in northwestern New Mexico preserve arguably the best early Paleocene mammalian record in North America and is the type location for the Puercan (Pu) and Torrejonian (To) North American land mammal ages (NALMA). However, the lack of precise depositional age constraints for the Ojo Alamo Sandstone and lower Nacimiento Formation has hindered our understanding of the timing and pacing of mammalian community change in the SJB following the Cretaceous–Paleogene mass extinction. Here we produced a high-resolution age model for the Ojo Alamo Sandstone and lower Nacimiento Formation combining magnetostratigraphy and 40Ar/39Ar geochronology spanning the first ∼3.5 m.y. of the Paleocene. Mean sediment accumulation rates during C29n were relatively low (<50 m/m.y.) and equalized from basin center to basin margin indicating an accommodation minimum; sediment accumulation rates approximately double (>90 m/m.y.) during C28r and are highest in the basin center and lowest on basin margin, which indicates high accommodation and an increase in basin subsidence near the C29n/C28r boundary (ca. 64.96 Ma). Puercan fossil localities were restricted to C29n, Torrejonian 1 localities to C28n, and lower Torrejonian 2 localities to C27r. Our revised age model for the SJB suggests that the first appearance of To1 mammals may have been diachronous across North America, with the Torrejonian 1 mammals first appearing in the north (Montana and North Dakota) during C29n, then in middle latitudes (Utah) in C28r, and lastly in southern North America (New Mexico) in C28n.
First mid-ocean ridge-type ophiolite from the Meso-Tethys suture zone in the north-central Tibetan plateau
Authors: Tang Yue , Zhai Qing-Guo , Chung Sun-Lin , Hu Pei-Yuan , Wang Jun , Xiao Xu-Chang , Song Biao , Wang Hai-Tao , Lee Hao-Yang
Published: March 2020

The Meso-Tethys was a late Paleozoic to Mesozoic ocean basin between the Cimmerian continent and Gondwana. Part of its relicts is exposed in the Bangong–Nujiang suture zone, in the north-central Tibetan Plateau, that played a key role in the evolution of the Tibetan plateau before the India-Asia collision. A Penrose-type ophiolitic sequence was newly discovered in the Ren Co area in the middle of the Bangong–Nujiang suture zone, which comprises serpentinized peridotites, layered and isotropic gabbros, sheeted dikes, pillow and massive basalts, and red cherts. Zircon U-Pb dating of gabbros and plagiogranites yielded 206Pb/238U ages of 169–147 Ma, constraining the timing of formation of the Ren Co ophiolite. The mafic rocks (i.e., basalt, diabase, and gabbro) in the ophiolite have uniform geochemical compositions, coupled with normal mid-ocean ridge basalt-type trace element patterns. Moreover, the samples have positive whole-rock εNd(t) [+9.2 to +8.3], zircon εHf(t) [+17 to +13], and mantle-like δ18O (5.8–4.3‰) values. These features suggest that the Ren Co ophiolite is typical of mid-ocean ridge-type ophiolite that is identified for the first time in the Bangong–Nujiang suture zone. We argue that the Ren Co ophiolite is the relic of a fast-spreading ridge that occurred in the main oceanic basin of the Bangong–Nujiang segment of Meso-Tethys. Here the Meso-Tethyan orogeny involves a continuous history of oceanic subduction, accretion, and continental assembly from the Early Jurassic to Early Cretaceous.
Onset of slip partitioning under oblique convergence within scaled physical experiments
Authors: Cooke Michele L. , Toeneboehn Kevin , Hatch Jennifer L.
Published: March 2020

Oblique convergent margins host slip-partitioned faults with simultaneously active strike-slip and reverse faults. Such systems defy energetic considerations that a single oblique-slip fault accommodates deformation more efficiently than multiple faults. To investigate the development of slip partitioning, we record deformation throughout scaled experiments of wet kaolin over a low-convergence (<30°), obliquely slipping basal dislocation. The presence of a precut vertical weakness in the wet kaolin impacts the morphology of faults but is not required for slip partitioning. The experiments reveal three styles of slip partitioning development delineated by the order of faulting and the extent of slip partitioning. Low-convergence angle experiments (5°) produce strike-slip faults prior to reverse faults. In moderate-convergence experiments (10°–25°), the reverse fault forms prior to the strike-slip fault. Strike-slip faults develop either along existing weaknesses (precut or previous reverse-slip faults) or through the coalescence of new echelon cracks. The third style of local slip partitioning along two simultaneously active dipping faults is transient while global slip partitioning persists. The development of two active fault surfaces arises from changes in off-fault strain pattern after development of the first fault. With early strike-slip faults, off-fault contraction accumulates to produce a new reverse fault. Systems with early lobate reverse faults accommodate limited strike-slip and produce extension in the hanging wall, thereby promoting strike-slip faulting. The observation of persistent slip partitioning under a wide range of experimental conditions demonstrates why such systems are frequently observed in oblique convergence crustal margins around the world.
Evaluation of a complex integrated, cross-sectoral psycho-oncological care program (isPO): a mixed-methods study protocol
Authors: Jenniches Imke , Lemmen Clarissa , Cwik Jan Christopher , Kusch Michael , Labouvie Hildegard , Scholten Nadine , Gerlach Alexander , Stock Stephanie , Samel Christina , Hagemeier Anna , Hellmich Martin , Haas Peter , Hallek Michael , Pfaff Holger , Dresen Antje
Published: March 2020

Introduction

International standards of care require the complete integration of psycho-oncological care into biomedical cancer treatment. The structured integrated, cross-sectoral psycho-oncological programme ‘isPO’ is aiming to ensure a provision of care in inpatient and outpatient settings according to a stepped-care approach. Up to now, psycho-oncological care is missing regulated and standardised processes to demonstrate the effectiveness. This study protocol describes the process and outcome evaluation that is conducted, along with the isPO study. The programme evaluation is aiming to proof effectiveness, explain potential discrepancies between expected and observed outcomes. Additionally, provide insight into the implementation process, as well as contextual factors that might promote or inhibit the dissemination and implementation of the stepped care programme will be gained. In addition to these measures, a cost–consequence analysis will provide further evidence aimed at integrating psycho-oncological care into primary healthcare.

Methods and analysis

The evaluation concept is based on a tripartite strategy consisting of a prospective, formative and summative evaluation. To capture all determinants, a concurrent mixed-method design is applied comprising qualitative (interviews and focus groups) and quantitative (standardised questionnaires) surveys of patients and healthcare providers. In addition, analysis of the psycho-oncological care data (isPO care data) and statutory health insurance claims data will be conducted. Primary and secondary data will complement one another (data linkage) to obtain a more comprehensive picture of the effectiveness and implementation of the complex intervention within the isPO study.

Ethics and dissemination

The study has been approved by the ethics committee of the Medical Faculty of the University of Cologne. For all collected data, the relevant national and European data protection regulations will be considered. All personal identifiers (eg, name, date of birth) will be pseudonymised. Dissemination strategies include annual reports as well as quality workshops for the organisations, the presentation of results in publications and on conferences, and public relations.

Trial registration number

DRKS00015326; Pre-results.
Dissemination and implementation of thee-MCHHandbook, UNRWA’s newly released maternal and child health mobile application: a cross-sectional study
Authors: Nasir Seif , Goto Ryunosuke , Kitamura Akiko , Alafeef Sahar , Ballout Ghada , Hababeh Majed , Kiriya Junko , Seita Akihiro , Jimba Masamine
Published: March 2020

Objectives

In April 2017, the United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA) released the electronicMaternal andChildHealth Handbook,thee-MCH Handbookapplication. One of the first mobile health (m-Health) interventions in a refugee setting, the application gives pregnant women and mothers access to educational information and health records on smartphones. This study investigated factors associated with the dissemination and implementation of m-Health in the refugee setting.

Setting and participants

A cross-sectional study was conducted in 9 of 25 UNRWA health centres for Palestine refugees in Jordan. Self-administered questionnaires were distributed for 1 week to pregnant women and mothers with children aged 0–5 years.

Outcome measures

The outcomes were whether participants knew about, downloaded or used the application. Multiple regression analyses were conducted to determine factors associated with application download and usage.

Results

1042 participants were included in the analysis. 979 (95.5%) had a mobile phone and 862 (86.9%) had a smartphone. 499 (51.3%) knew about, 235 (23.8%) downloaded and 172 (17.4%) used the application. Having other mobile applications (OR 6.17, p<0.01), staff knowledge of the application (OR 11.82, p<0.01), using the internet as a source of medical information (OR 1.63, p=0.01) and having internet access at home (OR 1.46, p=0.05) were associated with application download. The age of the husband was associated with application usage (OR 1.04, p=0.11).

Conclusions

Though m-Health may be a promising means of promoting health in refugees, multiple barriers may exist to its dissemination and implementation. Those who regularly use mobile applications and get medical information from the internet are potential targets of m-Health dissemination. For successful implementation of a m-Health intervention, health staff should have thorough knowledge of the application and users should have access to the internet. Husband-related factors may also play a role.
Animation-supported consent for urgent angiography and angioplasty: a service improvement initiative
Authors: Wald David S , Casey-Gillman Oliver , Comer Katrina , Mansell Josephine Sarah , Teoh Zhi H , Mouyis Kyriacos , Kelham Matthew , Chan Fiona , Ahmet Selda , Sayers Max , McCaughan Vincent , Polenio Nito
Published: March 2020

Objective

Patient understanding of angiography and angioplasty is often incomplete at the time of consent. Language barriers and time constraints are significant obstacles, particularly in the urgent setting. We introduced digital animations to support consent and assessed the effect on patient understanding.

Methods

Multi-language animations explaining angiography and angioplasty (www.explainmyprocedure.com/heart) were introduced at nine district hospitals for patients with acute coronary syndrome before urgent transfer to a cardiac centre for their procedure. Reported understanding of the reason for transfer, the procedure, its benefits and risks in 100 consecutive patients were recorded before introduction of the animations into practice (no animation group) and in 100 consecutive patients after their introduction (animation group). Patient understanding in the two groups was compared.

Results

Following introduction, 83/100 patients reported they had watched the animation before inter-hospital transfer (3 declined and 14 were overlooked). The proportions of patients who understood the reason for transfer, the procedure, its benefits and risks in the no animation group were 58%, 38%, 25% and 7% and in the animation group, 85%, 81%, 73% and 61%, respectively. The relative improvement (ratio of proportions) was 1.5 (95% CI 1.2 to 1.8), 2.1 (1.6 to 2.8), 2.9 (2.0 to 4.2) and 8.7 (4.2 to 18.1), respectively (p<0.001 for all comparisons).

Conclusion

Use of animations explaining angiography and angioplasty is feasible before urgent inter-hospital transfer and was associated with substantial improvement in reported understanding of the procedure, its risks and its benefits. The approach is not limited to cardiology and has the potential to be applied to all specialties in medicine.
Too much fertilizer? An observational association between inputs at planting and crop yield on a Saskatchewan farming operation
Authors: Pittman Tyler
Published: March 2020

Grain yield and its variability is a major driver of seeding rate and inorganic fertilizer use at planting among grain growers. Recommended rates for fertilizer application with regard to crop utilization and soil management are discretionary and vary between producer and agronomist. This observational case study with Bayesian inference examines the association between application rates of inorganic nitrogen, phosphorus, potassium chloride and sulphur at planting, and yield of durum wheat (Triticum turgidum L.), large green lentils (Lens culinaris Medik.), canola (Brassica napus L.), canaryseed (Phalaris canariensis L.), and spring barley (Hordeum vulgare L.). Using precision agriculture, input and crop yield information for each parcel of cultivated land was collected over a 4 yr period from 2015 to 2018 on a continuous no-till farming operation in the semiarid region of Saskatchewan, Canada. Hierarchical models were derived that accounted for yield variability in crop types due to the random effects of field, cultivar, crop planted in previous year, planting year, combine machine, observation location within field, and elevation. Evidence from this longitudinal study suggests that seed-placed fertilizer above the recommended safe rate can be associated with yield decline on farming operations in the semiarid environment of Saskatchewan, Canada.
Impedance spectroscopy of (TlGaSe2)1−x(TlInSe2)x solid solutions in radio frequency range
Authors: Sardarli R. M. , Salmanov F. T. , Alieva N. A. , Abbasli R. M.
Published: March 2020

The processes of charge transport on alternating current in [Formula: see text] solid solutions have been studied. It has been established that in weak alternating electric fields, there is a hopping mechanism of charge transfer over localized states in the vicinity of the Fermi level. A quantitative assessment of parameters was made in the framework of the effective medium theory and the Mott approximation. The use of impedance spectroscopy methods in [Formula: see text] solid solutions in the frequency range of 25–106 Hz, at temperatures of 180, 240 and 300 K charge transfer processes has been investigated. It was found that at 300 K in the low-frequency region, there are additional contributions to the conductivity, which, apparently, is associated with diffuse ion transfer near the boundary of the solid electrolyte and the electrode. Impedance locus curves, at low frequencies and at a temperature of 300 K, are characteristic of Warburg diffuse impedance.
Effect of Li interstitials on magnetic properties of V-doped LiZnAs
Authors: Wang Manfu , Tao Hualong , Liang Yao , Cui Yan , Liu Shimin , Zhang Zhihua , He Ming , Song Bo
Published: March 2020

First-principle calculations were performed to study electronic structures and magnetic properties of V-doped LiZnAs, as well as the effect of Li interstitial. The results showed that the magnetism origin of V-doped LiZnAs could be explained by [Formula: see text]–[Formula: see text] hybridization and the ferromagnetic (FM) state of the system was the ground state. The introduction of Li interstitials increased the distance between V and As atoms, which impaired the hybridization of V-[Formula: see text] and As-[Formula: see text]. As a result, the magnetic moment of V atom increased but the stability of FM coupling between V impurities was weakened.
Symmetries of Quotient Networks for Doubly Periodic Patterns on the Hexagonal Lattice
Authors: Stewart Ian , Gökaydin Dinis
Published: March 2020

Pattern formation, dynamics and bifurcations for lattice models are strongly influenced by the symmetry of the lattice. However, network structure introduces additional constraints, which sometimes affect the resulting behavior. We compute the automorphism groups of all doubly periodic quotient networks of the hexagonal lattice with nearest-neighbor coupling, with emphasis on “exotic” cases where this quotient network has extra automorphisms not induced by automorphisms of the square lattice. These cases comprise three isolated networks and two infinite families with wreath product structure. We briefly discuss the implications for pattern formation, dynamics and bifurcations. This paper is a sequel to a similar analysis of the square lattice and uses similar methods.
Stability and Bifurcation in a Predator–Prey System with Prey-Taxis
Authors: Qiu Huanhuan , Guo Shangjiang , Li Shangzhi
Published: March 2020

In this paper, we consider a generalized predator–prey system with prey-taxis under Neumann boundary condition, that is, the predators can survive even in the absence of the prey species. It is proved that for an arbitrary spatial dimension, the corresponding initial boundary value problem possesses a unique global bounded classical solution when the prey-taxis is restricted to a small range. Moreover, the local stabilities of constant steady states (including trivial, semi-trivial and positive constant steady states) are investigated. A further study on the coexistence steady state implies that the prey-taxis term suppresses the global asymptotical stability and influences the steady-state/Hopf bifurcations (if they exist). Analyses of steady-state bifurcation, Hopf bifurcation, and even Hopf/steady-state mode interaction are carried out in detail by means of the Lyapunov–Schmidt procedure. In particular, we obtain stable or unstable steady states, time-periodic solutions, quasi-periodic solutions, and sphere-like surfaces of solutions. These results provide theoretical evidences to the complex spatiotemporal dynamics found in numerical simulations.
Bifurcation Analysis in a Cancer Growth Model
Authors: Chang Yu , Wang Xiaoli , Feng Zhihong , Feng Wei
Published: March 2020

A mathematical model describing interactions among tumor cells, healthy host cells and immune cells is extensively investigated through bifurcation analysis with all parameters fixed except one bifurcation parameter. Transcritical bifurcation and saddle-node bifurcation are studied in the vector fields restricted to the corresponding center manifolds. Hopf bifurcation is analyzed in the frequency domain. In particular, the sixth-order harmonic balance approximations to the frequency and the amplitude of the periodic solutions, and the analytical expressions for these solutions are given. Numerical simulation study demonstrates various types of bifurcations and the complex solution behaviors, such as cyclic fold bifurcation, period-doubling bifurcation, period-doubling cascade and chaotic orbits. All these results complement previous theoretical studies on the model, and contribute to a better understanding of the qualitative dynamics of the cancer model.
On Weak Asymptotic Periodicity
Authors: Gryszka Karol
Published: March 2020

We introduce the asymptotic property associated with recurrence-like behavior of orbits in dynamical systems in general metric spaces. We define a notion of weak asymptotic periodicity and determine its elementary properties and relations including the invariance by topological conjugacy. We use the equicontinuity and the topology of the space to describe necessary and sufficient conditions for the existence of such a behavior.
Relative Entropy and Mean Li–Yorke Chaos for Biorderable Amenable Group Actions
Authors: Yan Kesong , Zeng Fanping
Published: March 2020

We consider the relative entropy and mean Li–Yorke chaos for [Formula: see text]-systems, where [Formula: see text] is a countable discrete infinite biorderable amenable group. We prove that positive relative topological entropy implies a multivariant version of mean Li–Yorke chaos on fibers for a [Formula: see text]-system.
A gradient boosted decision tree-based sentiment classification of twitter data
Authors: Neelakandan S. , Paulraj D.
Published: March 2020

People communicate their views, arguments and emotions about their everyday life on social media (SM) platforms (e.g. Twitter and Facebook). Twitter stands as an international micro-blogging service that features a brief message called tweets. Freestyle writing, incorrect grammar, typographical errors and abbreviations are some noises that occur in the text. Sentiment analysis (SA) centered on a tweet posted by the user, and also opinion mining (OM) of the customers review is another famous research topic. The texts are gathered from users’ tweets by means of OM and automatic-SA centered on ternary classifications, namely positive, neutral and negative. It is very challenging for the researchers to ascertain sentiments as a result of its limited size, misspells, unstructured nature, abbreviations and slangs for Twitter data. This paper, with the aid of the Gradient Boosted Decision Tree classifier (GBDT), proposes an efficient SA and Sentiment Classification (SC) of Twitter data. Initially, the twitter data undergoes pre-processing. Next, the pre-processed data is processed using HDFS MapReduce. Now, the features are extracted from the processed data, and then efficient features are selected using the Improved Elephant Herd Optimization (I-EHO) technique. Now, score values are calculated for each of those chosen features and given to the classifier. At last, the GBDT classifier classifies the data as negative, positive, or neutral. Experiential results are analyzed and contrasted with the other conventional techniques to show the highest performance of the proposed method.
Approximate Solution of Homogeneous and Nonhomogeneous 5αth-Order Space-Time Fractional KdV Equations
Authors: Biswas Swapan , Ghosh Uttam
Published: March 2020

In this paper, the semi-inverse method is applied to derive the Lagrangian of the [Formula: see text]th Korteweg de Vries equation (KdV). Then the time and space differential operators of the Lagrangian are replaced by corresponding fractional derivatives. The variation of the functional of this Lagrangian is devoted to lead the fractional Euler Lagrangian via Agrawal’s method, which gives the space-time fractional KdV equation. Jumarie derivative is used to obtain the space-time fractional KdV equations. The homotopy analysis method (HAM) is applied to solve the derived space-time fractional KdV equation. Then numerical solutions are compared with the known analytical solutions by tables and figures.
A Finite Pointset Method for Extended Fisher–Kolmogorov Equation Based on Mixed Formulation
Authors: Doss L. Jones Tarcius , Kousalya N.
Published: March 2020

In this paper, numerical solutions of the extended Fisher–Kolmogorov equation are obtained using finite pointset method. Finite pointset method is a meshless method which is a local iterative method based on the weighted least square approximation. By employing splitting technique, the extended Fisher–Kolmogorov equation is split into a two coupled system of differential equations by introducing an intermediate function. The method is applied to the resulting coupled system of differential equation. The numerical results confirm the good efficiency of the finite pointset method.
Enhancing Frequency and Reducing the Power of Spin-Torque Nanooscillator By The Generated Oersted Field
Authors: Bhoomeeswaran H. , Sabareesan P.
Published: March 2020

The current-driven magnetization precession dynamics stimulated by Spin-Transfer Torque (STT) in a trilayer spin-valve device (typically Spin-Torque Nanooscillator (STNO)) is numerically investigated by solving the Landau–Lifshitz–Gilbert–Slonczewski (LLGS) equation. We have devised four STNO devices made of ferromagnetic alloys such as CoPt, CoFeB, Fe[Formula: see text]B[Formula: see text]Ni2 and EuO, which act as free and fixed layers. Here, copper acts as a nonmagnetic spacer for all the devices. In this work, we have introduced the current-induced Oersted field, which is generated when a spin-polarized current passes through the device. The generated Oersted field strength is varied by increasing the diameter of the STNO device. Frequency tunability is achieved in all the four devices, whereas the power of the individual device reduces. The frequency and power of the devices depend entirely on the saturation magnetization of the material, which inherently reflects in the current density and the coherence of the spin-polarized DC. In all devices, the frequency increases, whereas the power decreases by increasing the strength of the Oersted field. Among the four devices, the maximum frequency can be tuned up to 104[Formula: see text]GHz with 40[Formula: see text]nm device diameter, which is obtained for EuO material. This opens a promising source and paves a glittering future for the nanoscale spintronic devices.
The New Age of Cell-Free Biology
Authors: Noireaux Vincent , Liu Allen P.
Published: March 2020

The cell-free molecular synthesis of biochemical systems is a rapidly growing field of research. Advances in the Human Genome Project, DNA synthesis, and other technologies have allowed the in vitro construction of biochemical systems, termed cell-free biology, to emerge as an exciting domain of bioengineering. Cell-free biology ranges from the molecular to the cell-population scales, using an ever-expanding variety of experimental platforms and toolboxes. In this review, we discuss the ongoing efforts undertaken in the three major classes of cell-free biology methodologies, namely protein-based, nucleic acids–based, and cell-free transcription–translation systems, and provide our perspectives on the current challenges as well as the major goals in each of the subfields.
Computational Fluid Dynamics for Fixed Bed Reactor Design
Authors: Dixon Anthony G. , Partopour Behnam
Published: March 2020

Flow, heat, and mass transfer in fixed beds of catalyst particles are complex phenomena and, when combined with catalytic reactions, are multiscale in both time and space; therefore, advanced computational techniques are being applied to fixed bed modeling to an ever-greater extent. The fast-growing literature on the use of computational fluid dynamics (CFD) in fixed bed design reflects the rapid development of this subfield of reactor modeling. We identify recent trends and research directions in which successful methodology has been established, for example, in computer generation of packings of complex particles, and where more work is needed, for example, in the meshing of nonsphere packings and the simulation of industrial-size packed tubes. Development of fixed bed reactor models, by either using CFD directly or obtaining insight, closures, and parameters for engineering models from simulations, will increase confidence in using these methods for design along with, or instead of, expensive pilot-scale experiments.