bluuebunny/crossref_metadata_2025 huggingface dataset:
Al Alloy Tailor-Welded Blanks Fabrication via Friction Stir Welding: Effect of Shoulder Size
Authors: Majeed Tanveer , Ansari Nooruddin , Mehta Yashwant , Siddiquee Arshad Noor
Published: September 2021

Material flow and heat generation by tool shoulder during Friction Stir Welding (FSW) significantly alters the microstructural and thermomechanical behavior of joints. The effect of shoulder size on mechanical properties of joints has not yet been reported in the FSW of Tailor-Welded Blanks (TWBs). This article reports the effect of shoulder size on joint quality in FSW of TWBs between 6.35 mm thick plates of AA2024-T3 and 2.5 mm thick plates of AA7475-T7 alloys in butt joint configuration fabricated under shoulder sizes: 18 mm, 20 mm, and 22 mm. Microstructural evaluation of FSWed joints reveals a significant increase in grain size with shoulder size. The X-ray energy-dispersive spectroscopic (EDS) elemental maps reveal the presence of fine second phase particles in the stir zone. The progressive elimination of void defects with the increase in shoulder size was observed. The tensile testing reveals the highest strength of joints fabricated via shoulder size of 18 mm. Fractographic analyses of broken tensile specimens showed the mixed mode of failure in all the welded specimens.
Al2O3 Toughening ScSZ Electrolyte Fabricated by Water-Based Tape Casting Technique for Solid Oxide Fuel Cells
Authors: Wang Haoran , Lei Ze , Zhang Han , Li Yongkang , Jing Junmeng , Jin Yiqian , Yang Zhibin , Peng Suping
Published: September 2021

A water-based tape-casting slurry is reported to prepare the ceria and scandia co-doped zirconia (ScSZ) electrolyte films. The slurry is characterized and optimized through Zeta potential and rheological property measurements. Smooth and flat ScSZ electrolyte films are obtained by improving the sintering process. The microstructure, electrical performance, and mechanical property of ScSZ with adding different contents of Al2O3 are also investigated. The results show that a proper amount of Al2O3 has a beneficial effect on the densification of ScSZ. A significant decrease in the grain boundary resistance of ScSZ is observed by adding 0.5 wt% Al2O3. The bending strength of the sample with 0.5 wt% Al2O3 (ScSZ-0.5A) is about 400 MPa, which is 20% higher than pure ScSZ. The ScSZ-0.5A electrolyte film fabricated by the water-based tape-casting method shows appropriate electrical conductivity and high mechanical strength, which is promising for practical application in solid oxide fuel cells (SOFCs).
Preparation of Fe/N Co-Doped Hierarchical Porous Carbon Nanosheets Derived From Chitosan Nanofibers for High-Performance Supercapacitors
Authors: Yang Yaqi , Shao Ziqiang , Wang Feijun
Published: September 2021

Due to the low specific capacitance and small specific surface area of conventional carbon materials used as electrode materials for double-layer capacitors, the search for more ideal materials and ingenious preparation methods remains a major challenge. In this study, fractional porous carbon nanosheets were prepared by co-doping Fe and N with chitosan as nitrogen source. The advantage of this method is that the carbon nanosheets can have a large number of pore structures and produce a large specific surface area. The presence of Fe catalyzes the graphitization of carbon in the carbon layer during carbonization process and further increases the specific surface area of the electrode material. This structure provides an efficient ion and electron transport pathway, which enables more active sites to participate in the REDOX reaction, thus significantly enhancing the electrochemical performance of SCs. The specific surface area of CS-800 is up to 1587 m2 g−1. When the current density is 1 A g−1, the specific capacitance of CS-800 reaches 319.5 F g−1 and remains 84.61% of the initial value after 10,000 cycles. The Coulomb efficiency of CS-800 is almost 100% after a long cycle, which indicates that CS-800 has more ideal double-layer capacitance and pseudo capacitance.
Algorithmic Selection of Sliding–Sticking Contacts in Robotic In-hand Manipulation
Authors: Kumar Rajesh , Mukherjee Sudipto
Published: September 2021

The paper describes a kinematic method for robotic in-hand manipulation of objects. The method focuses on repositioning the object using a combination of sticking and sliding robotic contacts. Two fingertips with sliding contacts are fixed in space while the remaining two fingertips actively manipulate the object without a change in the point of contact with the object. When sliding over two fixed contacts, the object is constrained to a “three-parameter twist space” if it is not programmed to rotate about the line joining the two fixed contacts. A gradient-descent-based kinematic algorithm is developed to project the desired twist to the allowable twist space, generating a movement sequence of robotic fingertips. The transition from fixed support vis-á-vis the sticking contacts for manipulating the object also emerges from the algorithm.
Using the Few-Group Approximation for Calculating Some Neutron-Physical Characteristics of VVER-1000 Core by Means of the Monte Carlo Universal Code
Authors: Bikeev A. S. , Daichenkova Yu. S. , Kalugin M. A. , Shkarovsky D. A. , Shkityr V. V.
Published: September 2021

The main purpose of this work is to study the possibility of using the few-group approximation for calculation of some neutron-physical characteristics of VVER-1000 core by means of special version of Monte Carlo Universal code. The Monte Carlo method for VVER-1000 core neutron-physical characteristics calculation using the few-group approximation with an estimate of neutron cross sections “by location” was provided and tested in this research. The reduction of calculation time due to the transition from a pointwise model of representation of cross sections to the few-group approximation and methodical error of this approach were evaluated. Optimal number of energy groups was determined. It was found that consideration of the scattering anisotropy leads to a significant decrease in methodical error. Ways of further reduction of methodical error were worked out.
Nanoliquid Jet Impingement Heat Transfer for a Phase Change Material Embedded Radial Heating System
Authors: Selimefendigil Fatih , Öztop Hakan F.
Published: September 2021

Nanoliquid impingement heat transfer with a phase change material (PCM) installed radial system is considered. The study is performed by using the finite element method for various values of Reynolds numbers (100 ≤ Re ≤ 300), height of PCM (0.25H ≤ hpcm ≤ 0.75H), and plate spacing (0.15H ≤ hs ≤ 0.40H). Different configurations using water, nanoliquid, and nanoliquid + PCM are compared in terms of heat transfer improvement. Thermal performance is improved by using PCM, while best performance is achieved with nanoliquid and PCM-installed configuration. At Re = 100 and Re = 300, heat transfer improvements of 26% and 25.5% are achieved with the nanoliquid + PCM system as compared to water without PCM. The height of the PCM layer also influences the heat transfer dynamic behavior, while there is 12.6% variation in the spatial average heat transfer of the target surface with the lowest and highest PCM heights while discharging time increases by about 76.5%. As the spacing between the plates decreases, average heat transfer rises and there is 38% variation.
Aerodynamic Functional Diagnostics Based on Angular Momentum Transport Lines
Authors: Yang Xiang IA , Jariwala Vishal , Xu Haosen HA , Larosiliere Louis
Published: September 2021

In analogy with the classical concept of mass-flux-based streamlines, we define angular momentum transport (AMT) lines as an aerodynamic functional diagnostic tool. The AMT lines are the ones whose tangents are given by the average angular momentum flux. The mathematical and physical properties of these AMT lines are exploited to study the generation, removal, and transport of angular momentum in turbomachinery components. We illustrate the concept by visualizing AMT lines in two relatively simple flows, namely, vaneless incompressible diffuser and von Karman flow (a model of centrifugal compressors). Next, we apply the proposed diagnostic tool to flow in a return channel. A return channel is a part of a multistage centrifugal compressor stage. Its principal function is to remove angular momentum. In this work, we apply the diagnostic tool of AMT lines to a Reynolds-averaged Navier Stokes (RANS) simulation and a wall-modeled large eddy simulation (LES) of flow in the return channel. We show that AMT lines give us insights into the AMT process that are otherwise not available with conventional visualization tools.
“Moving out of the safe zone”: Promoting learning communities and reflective supervision in a social work statutory child protection agency
Authors: Rankine Matt , Thompson Andrew
Published: September 2021

INTRODUCTION: Social work supervision in statutory child protection settings is often confused with line management and has little focus on professional development, critical reflection and exploration of practice. Within Aotearoa New Zealand, the statutory child protection agency Oranga Tamariki (OT), is under considerable scrutiny regarding the management of risk, child abuse, and the over-representation of Ma ̄ori tamariki within the child welfare system. This article covers the first collection of findings from a larger supervision study.METHODS: Using critical reflection as the methodological lens, four experienced OT supervisors participated in a learning community where supervision recordings were brought to each meeting to improve reflective capacity, critical reflection and skills. Data were collected from the learning community and thematic analysis was undertaken to explore current supervision practice in OT.FINDINGS: The three themes generated from the learning community discussions were: supervisory skills/interventions; the structure of supervision; and working with emotion and trauma. These themes highlighted the significance of the learning community as a forum for supervisors to share their existing supervision practice together, “moving out of the safe zone” as they engaged in positive and constructive feedback with their colleagues in a supportive space.CONCLUSIONS: Reflective supervision, within statutory child protection, is essential for learning, critical reflection and cultivating robust decision making in social work practice. The creation and development of professional supervision spaces such as learning communities provide the basis for supervisors and supervisees to develop their skills and ensure accountable, anti-oppressive and ethical practice.
Effective leadership, management and supervision in health and social care (3rd ed.)
Authors: Smithson Diane
Published: September 2021

Book review
Young’s Two-Slit Experiment Without a Laser
Authors: Sharpe J. P. , Yee C.
Published: September 2021

The Young’s two-slits experiment is arguably one of the most famous and beautiful experiments in physics. In introductory physics labs the experiment is almost exclusively carried out using a laser, and it is introduced this way in some introductory physics textbooks. In the case of laser illumination, light passes directly through the slits and spreads out by diffraction so that interference fringes can be viewed on a distant screen. Most students, in our experience, are unaware that the experiment can be carried out in any other way. But the laser approach depends on the remarkable light emitted by the laser: it is spatially coherent, meaning that the phase relationship between the light emitted from the slits is constant, and it is extremely bright, meaning that real interference fringes can be seen on the screen. When carried out with classical, incoherent light, a quasi-monochromatic source such a sodium lamp must first be rendered spatially coherent by focusing the light through a pinhole and then using this light to illuminate the two slits. Fringe patterns will certainly be formed, but they need to be observed by either viewing with an eyepiece or allowing them to fall directly on the photosensor of a camera. It is implied in other physics texts that the fringe pattern can be cast onto a screen and viewed, but this is not feasible because the fringes are just not bright enough. Here we report an arrangement where an extended incoherent source can be used and fringes made bright enough to be observed on a screen.
Discovering Newton’s Second Law of Motion in the Classroom
Authors: Austin Robert Andreas
Published: September 2021

Richard Feynman, in one of the Messenger Lectures he delivered at Cornell University in 1964, explained that one looks for a new law of nature by the following process:
How Eccentric Is the Orbit of the Earth, and Where Is the Sun?
Authors: Rovšek Barbara
Published: September 2021

At a conference on educational physics, someone described a series of multiple-choice problems to test students’ ideas about various mechanical phenomena. One of the problems questioned students’ conceptions about the shape of the Earth’s orbit in the solar system. The question was as follows: Which of the following schematic illustrations corresponds most accurately to the real situation regarding the position of the Sun and the shape of the Earth’s trajectory around the Sun, when viewed from top?
A New Lecture-Tutorial for Teaching Interferometry to Astro 101 Students
Authors: Wallace Colin S. , Hatcher Chase , Chambers Timothy G. , Hornstein Seth D. , Kamenetzky Julia , Prather Edward E.
Published: September 2021

The ground-breaking image of a black hole’s event horizon, which captured the public’s attention and imagination in April 2019, was captured using the power of interferometry: many separate telescopes working together to observe the cosmos in incredible detail. Many recent astrophysical discoveries that have revolutionized the scientific community’s understanding of the cosmos were made by interferometers such as LIGO, ALMA, and the Event Horizon Telescope. Astro 101 instructors who want their students to learn the science behind these discoveries must teach about interferometry. Decades of research show that using active learning strategies can significantly increase students’ learning and reduce achievement gaps between different demographic groups over what is achieved from traditional lecture-based instruction. As part of an effort to create active learning materials on interferometry, we developed and tested a new Lecture-Tutorial to help Astro 101 students learn about key properties of astronomical interferometers. This paper describes this new Lecture-Tutorial and presents evidence for its effectiveness from a study conducted with 266 Astro 101 students at the University of North Carolina at Chapel Hill.
Nodes and Antinodes in Two-Color Chladni Figures
Authors: Cortel Adolf
Published: September 2021

Chladni patterns are one of the most fascinating physics demonstrations. They can be produced very easily using commercially available apparatus based on metallic plates attached to a mechanical driver, similar to a loudspeaker without the membrane, and a signal generator. The figures are observed using sand sprinkled on the surface of the plate. The demonstration is even more impressive if the figures are produced by using a violin bow. In the usual demonstration the patterns show the nodal lines of the vibrating plate: the sand moves from the vibrating regions towards the nodes, where it remains at rest. This paper describes how the demonstration can be improved by using two different powders to produce two-color Chladni figures, where nodes and antinodes display different colors.
The Physical Cause of Atmospheric Pressure: Weight of Air or Molecular Motion and Impacts?
Authors: Sliško Josip , Topalović Tatjana Marković , Božić Mirjana
Published: September 2021

The question from the title is raised because in almost all introductory physics courses/textbooks the atmospheric pressure has been attributed to the weight of the column of air from a given level in the atmosphere up to its top. “Air is pressing on air.” However the same textbooks, in the chapter on the kinetic theory of gases, tell students that a pressure in a gas enclosed in a container is due to variation of momentum suffered by the molecules, as a consequence of their impacts against the walls or against the surface of a test object placed inside the gas. The higher the number and average energy of molecules, the higher the pressure. Despite the fact that the atmosphere consists of matter that is mostly in the gas state, introductory physics textbooks do not justify why the concept of pressure from the kinetic theory of gases would not explain the physical nature of pressure in the atmosphere. Ricci-Torricelli’s experiments realized by scientists from the Academia del Cimento suggest to abandon the “weight based” explanation in favor of a density-based explanation of atmospheric pressure. The dependence on altitude of air density, as well as of air pressure, is caused by Earth’s gravitational force acting on all chaotically moving molecules in the atmosphere.
A Scaffolded Approach to Laboratory Report Writing for Non-Major and Introductory Physics Classes
Authors: Riegel Kimberly
Published: September 2021

Laboratory report assignments for non-major and introductory classes can be challenging because the students are unfamiliar with the type of technical writing required and the subject matter. These issues for the student make the grading for the instructor difficult and time consuming. Determining the level of detail to require, the format, and how to distribute the grading between good writing and physics knowledge is a difficult balancing act. Many courses use laboratory reports to assess if a student can communicate scientific concepts effectively so ignoring the writing issues is not an option, but many students have no experience reading technical documents, let alone writing them. Furthermore, the students need to understand the scientific concepts to effectively communicate them. In this article, a method for providing a scaffolded approach to lab reports is given. This approach aims to provide the student with some much needed examples of technical writing while they are new to the laboratory environment and the course material. A sample lab report template was provided with key information and conclusions removed. As the course continued, the students were required to do an increasing amount of independent writing while the provided content was slowly decreased. By the end of the course the students submitted full independently written lab reports.
Low-Cost Astrophotography with a Smartphone: STEAM in Action
Authors: Paula Marcos Emanuel , Micha Daniel Neves
Published: September 2021

Astrophotography has been responsible for the discovery of planets, solar systems, stars, and several other celestial objects, which directly helps with expanding our knowledge about the universe and creating scientific models for nature. Practical techniques have been extensively described, including Covington, who has published an extensive guide to amateur astrophotography. Furthermore, aiming to introduce such important scientific activity among students, several authors have described possibilities of using the technique in physics and astronomy teaching. However, the proposed activities and methods normally need expensive equipment, such as telescopes, professional cameras, mounts, tripods, optical components, and other items not commonly owned by teachers, students, or the general public.The ubiquity of the smartphone, especially among students, makes it interesting for educational purposes. The device can be used as a mobile laboratory due to the several integrated sensors. Furthermore, the possible uses in classroom are extensive, including the ones involving astronomical subjects, especially with the use of its camera for sky imaging. In this work, we propose a simple and low-cost technique for the practice of astrophotography using the smartphone. Moreover, we suggest teaching activities involving the STEAM disciplines (science, technology, engineering, the arts, and math), including the analysis of the Earth’s rotation and the artistic treatment of the astrophotographs.
Bringing Physical Physics Classroom Online – Challenges of Online Teaching in the New Normal
Authors: Tan Da Yang , Chen Jer-Ming
Published: September 2021

The onset of the COVID-19 pandemic in 2020 greatly impacted all forms of social activities globally, including traditional classroom activities across all levels of instruction (kindergarten to universities). While online and blended learning (including MOOCs) have been an active subject of research and discourse during the pre-pandemic days, onset of the pandemic created an immediacy to such means of course delivery better than any administrator or teaching committee could have. This created both a gap and tension in terms of successful and engaging content delivery, where traditional modes of synchronous content delivery were forced online. This situation provided educators with an opportunity to explore the merits and weaknesses of online learning. Thus, this article seeks to outline the challenges and paradigm shifts involved in such synchronous online learning as a replacement for traditional classroom learning, following our experience at Singapore University of Technology and Design (SUTD) of conducting a full 13-week online physics course between May to August 2020. At the same time, we reflect on the merits brought about by the availability of such technologies that can potentially be translated back to the physical physics classroom.
Improving Experiential Learning in Sport Management Through Work-Integrated Learning
Authors: Foster Susan B. , Pierce David A.
Published: September 2021

Experiential learning has played an integral role in curricular innovation since the inception of North American sport management education. However, internationally, work-integrated learning, and specifically cooperative education, have proven to be robust methods for preparing students for the workforce with little to no mention of these terms as applied to sport management curricula in the United States. This educational research review positions involving both of these structured pedagogies that combine classroom instruction with highly contextualized, authentic work experiences of at least two semesters to improve experiential learning and calls for more research to be done to demonstrate its efficacy. Recommendations are made to spur faculty to consider ways these pedagogies can be applied to their sport management curricula. In addition, this review addresses keys to successfully implement them on campus.
Architectures of neuronal circuits
Authors: Luo Liqun
Published: September 2021

General principles of neuronal communication

The explosion of modern technologies over the past years has produced vast amounts of knowledge about the molecular, anatomical, and physiological properties of individual neurons. However, individual neurons do not function in isolation; they interact with each other in circuits to process information. Luo attempted to synthesize different types of investigations to extract generalized principles underlying how neurons communicate with each other through specific patterns of synaptic connectivity. Although different elements of the projection motifs and architectural plans have been discussed separately in the past, these motifs and architectures can now be brought together in the same intellectual framework. —PRS
Vortex beams of atoms and molecules
Authors: Luski Alon , Segev Yair , David Rea , Bitton Ora , Nadler Hila , Barnea A. Ronny , Gorlach Alexey , Cheshnovsky Ori , Kaminer Ido , Narevicius Edvardas
Published: September 2021

Vortex beams of nonelementary particles

The discovery of photon and electron vortex beams carrying orbital angular momentum (as a result of a twisting wave front) has led to appreciable advances in optical imaging, optical and electron microscopy, communications, quantum optics and micromanipulation, and more advances are expected. In an effort to extend this progress to other types of beams, Luski
et al
. demonstrate the production of vortex beams of helium atoms and dimers formed from supersonic beams with large coherence lengths diffracted off of specifically nanofabricated gratings with fork dislocations (see the Perspective by Kornilov). Vortex beams made of nonelementary particles with internal degrees of freedom represent a direct manifestation of quantum mechanics on macroscopic scale, and their production paves the way for many long-awaited applications. —YS
Transformational ecology and climate change
Authors: Jackson Stephen T.
Published: September 2021

Management of imminent ecosystem shifts demands adaptive, translational approaches
Stressing out translation
Authors: Mellado Wilfredo , Willis Dianna E.
Published: September 2021

Integrated stress response activation drives neuropathy in Charcot-Marie-Tooth disease
Steven Weinberg (1933–2021)
Authors: Preskill John
Published: September 2021

Titan of theoretical physics
Stratospheric winds trigger cold spells
Authors: Coumou Dim
Published: September 2021

Changes in Arctic sea ice and snow cover can alter wind patterns at high altitudes
In Science Journals
Authors: Funk Michael A. , Diesner Jana , Jiang Di , Stajic Jelena , Vinson Valda , Foley John F. , Smith H. Jesse , Osborne Ian S. , Hurtley Stella M. , Suleymanov Yury , Smith Keith T. , Purnell Beverly A. , Hines Pamela J. , Erkes Dan A. , Stern Peter , Maroso Mattia
Published: September 2021

Highlights from the
Science
family of journals
In Other Journals
Authors: Sugden Andrew M. , Alderton Gemma , Smith H. Jesse , Grocholski Brent , Ash Caroline , Osborne Ian S. , Vinson Valda
Published: September 2021

Editors’ selections from the current scientific literature
Call of the wild
Authors: Cohen Jon
Published: September 2021

Why most scientists say it’s unlikely that SARS-CoV-2 originated from a “lab leak”
SARS-CoV-2 infection confers greater immunity than shots
Authors: Wadman Meredith
Published: September 2021

Study from Israel, the largest of its kind, also finds infection combined with a single jab is highly protective
Using mirrors to tame the savage x-ray laser
Authors: Cho Adrian
Published: September 2021

Scheme that harkens back to ordinary lasers could open new research avenues
Molecular cleanup crew moves outside the cell
Authors: Service Robert F.
Published: September 2021

Drug candidates now target extracellular proteins, broadening diseases they may treat
JUN promotes hypertrophic skin scarring via CD36 in preclinical in vitro and in vivo models
Authors: Griffin Michelle F. , Borrelli Mimi R. , Garcia Julia T. , Januszyk Michael , King Megan , Lerbs Tristan , Cui Lu , Moore Alessandra L. , Shen Abra H. , Mascharak Shamik , Diaz Deleon Nestor M. , Adem Sandeep , Taylor Walter L. , desJardins-Park Heather E. , Gastou Marc , Patel Ronak A. , Duoto Bryan A. , Sokol Jan , Wei Yuning , Foster Deshka , Chen Kellen , Wan Derrick C. , Gurtner Geoffrey C. , Lorenz Hermann P. , Chang Howard Y. , Wernig Gerlinde , Longaker Michael T.
Published: September 2021

JUN drives scarring by modifying the roles of fibroblast subpopulations, and JUN antagonism via CD36 may represent an antiscarring therapy.
Comparison of the clinical outcomes of percutaneous kyphoplasty for the management of osteolytic and osteoblastic-related metastatic vertebral lesions
Authors: Wu Wence , Zhang Xinxin , Li Xiaoyang , Liu Huanmei , Xu Libin , Liu Ting , Yu Shengji
Published: September 2021

Objective

To retrospectively compare the clinical efficacy and safety of percutaneous kyphoplasty (PKP) for the management of osteolytic and osteoblastic-related metastatic vertebral lesions.

Methods

A total of 117 patients with osteolytic (87 cases, 159 lesions, OL group) or osteoblastic-related (30 cases, 56 lesions, OB group) metastatic vertebral lesions underwent PKP. The clinical efficacy was assessed based on parameters including Visual Analog Scale (VAS), Oswestry Disability Index (ODI), vertebral body height (VBH) variation, and quality of life (QoL). Major and minor complications were systematically evaluated to assess the safety of the procedure.

Results

No significant differences were found in the age, sex, or amount of bone cement between both groups (p>0.05). Compared with the OB group, the OL group was superior in operation duration (p<0.05) but was inferior in inflation pressure (p<0.05). Both groups experienced significant pain relief and improvement in the ODI, VBH, and QoL after PKP (p<0.05). The OB group had a better pain relief according to the VAS score but a poorer VBH restoration than the OL group throughout the follow-up period (p<0.05). No significant differences were observed in ODI and QoL between the two groups (p>0.05). The incidence of complications in the OL group was significantly higher than that in the OB group (p<0.05).

Conclusions

PKP can safely achieve pain relief, functional improvement, VBH restoration, and QoL improvement for patients with osteolytic or osteoblastic-related metastatic vertebral lesions. Patients with osteolytic metastatic vertebral lesions showed better VBH restoration and had a shorter operation time but experienced less pain relief and had a greater incidence of complications than patients with osteoblastic-related metastatic vertebral lesions after PKP.
Socioeconomic settings and food consumption patterns of 2–5-year-old children in developed countries: a scoping review
Authors: Anstruther Se’era May , Barbour-Tuck Erin , Vatanparast Hassan
Published: September 2021

Introduction: Early childhood overweight and obesity, as a result of unhealthy dietary habits and sedentary life, is a growing global public health concern, particularly in Canada. There are limited data on how socioeconomic factors influence dietary habits of young children living in developed countries. Methods: We conducted a scoping review to examine the existing literature on how socioeconomic settings influence food consumption patterns of children 2–5 years old in developed countries. The inclusion criteria were relevant articles in the English language between 2007 and 2019. Results: From the initial 1854 articles, only 12 articles from Europe, Canada, and the United States met the inclusion criteria. There are differences in eating patterns of preschool-aged children based on parental education, whereas income level did not have a clear influence on dietary patterns. The existing studies suffer from a variety of limitations that limit a cohesive conclusion. Conclusion: Studies with children 2–5 years old are scarce. Parental education seems to influence the dietary habits of young children, whereas the role of income is not clear. There is a need for further high-quality research, preferably longitudinal studies, to inform health promotion initiatives and preventive strategies to facilitate healthy growth and development in young children.
Electronic and optical response of HfO2: DFT calculations with Ti and Zr incorporation
Authors: Khan M. Junaid Iqbal , Yousaf Muhammad , Ramay Shahid M. , Mahmood Asif , Ullah Hamid , Saleem Murtaza
Published: September 2021

Optical properties of semiconductor materials have been intensively studied for potential applications in perovskite solar cells. HfO2is recently substituting the conventional semiconductor materials due to excellent photovoltaic characteristics. The electronic and optical properties of Ti- and Zr-incorporated HfO2were investigated in this work using density functional theory. Ab-initio calculations were performed using Perdew–Burke–Ernzerhof (PBE) generalized gradient approximation (GGA). Electronic properties were studied by analyzing the band structure and density of states. Refractive index, attenuation coefficient, dielectric function, loss factor, energy loss spectra and absorption coefficient were calculated for the detailed study of optical response. A significant increase in absorption of HfO2in the visible region with the incorporation of Ti revealed its important practicability in photovoltaic devices.
Generalized r-Lambert Function in the Analysis of Fixed Points and Bifurcations of Homographic 2-Ricker Maps
Authors: Leonel Rocha J. , Taha Abdel-Kaddous
Published: September 2021

This paper aims to study the nonlinear dynamics and bifurcation structures of a new mathematical model of the [Formula: see text]-Ricker population model with a Holling type II per-capita birth function, where the Allee effect parameter is [Formula: see text]. A generalized [Formula: see text]-Lambert function is defined on the 3D parameters space to determine the existence and variation of the number of nonzero fixed points of the homographic [Formula: see text]-Ricker maps considered. The singularity points of the generalized [Formula: see text]-Lambert function are identified with the cusp points on a fold bifurcation of the homographic [Formula: see text]-Ricker maps. In this approach, the application of the transcendental generalized [Formula: see text]-Lambert function is demonstrated based on the analysis of local and global bifurcation structures of this three-parameter family of homographic maps. Some numerical studies are included to illustrate the theoretical results.
Predicting Limit Cycle Boundaries Deep Inside Parameter Space of a 2D Biochemical Nonlinear Oscillator Using Renormalization Group
Authors: Dutta Ayan , Roy Jyotipriya , Banerjee Dhruba
Published: September 2021

Formation and study of periodic orbits in phase space in the case of nonlinear oscillators have been a topic of much interest in the recent past. In the current work, a method to go deep inside the limit cycle zone on one side of the bifurcation curve of a 2D non-Lienard biochemical oscillator has been introduced. It is discussed how such an introduction facilitates predicting the boundaries of limit cycles at various points of parameter space, nearly accurately, by the use of perturbative Renormalization Group. Sel’kov model of Glycolytic oscillator has been chosen as the base model to introduce the method.
Steady-State Problem of an S-K-T Competition Model with Spatially Degenerate Coefficients
Authors: Zhou Hao , Wang Yu-Xia
Published: September 2021

In this paper, we study the steady-state problem of an S-K-T competition model with a spatially degenerate intraspecific competition coefficient. First, the global bifurcation continuum of positive steady-state solutions from its semitrivial steady-state solution is given, which depends on the spatial heterogeneity and cross-diffusion. Second, two limiting systems are derived as the cross-diffusion coefficient tends to infinity. Moreover, we demonstrate the existence of positive steady-state solutions near the two limiting systems, and show which one of the limiting systems characterizes the positive steady-state solution.
Shrinkage properties of natural and diesel oil-contaminated fine soils from central Poland
Authors: Izdebska-Mucha Dorota , Wójcik Emilia
Published: September 2021

The objectives of this paper are to provide a regional description of the shrinkage parameters of Neogene clays and glacial tills from central Poland; and to present the effects of hydrocarbon contamination on the shrinkage behaviour of soils. Forty samples containing from 19 to 90% clay-size particles were tested. The comparison of the three methods applied has indicated that the shrinkage limit values obtained by the BS 1377-2 method provide a greater margin of safety when used in the classification of expansive soils and yield the best match in the analysis of the variability of the shrinkage limit in relation to other soil index parameters. A good correlation was found between the shrinkability index and the consistency index, which leads to a new classification of soils. The shrinkage tests of clean and diesel oil-contaminated samples revealed that contamination has a significant and irregular effect on the values of shrinkage parameters. For a low degree of contamination the shrinkage limit of both soils had the lowest values and the volumetric shrinkage was at its maximum, and with increasing diesel oil content the shrinkage limit values tend to increase whereas the volumetric shrinkage decreased.
Social Robots for the Care of Persons with Dementia
Authors: Ghafurian Moojan , Hoey Jesse , Dautenhahn Kerstin
Published: September 2021

Intelligent assistive robots can enhance the quality of life of people with dementia and their caregivers. They can increase the independence of older adults, reduce tensions between a person with dementia and their caregiver, and increase social engagement. This article provides a review of assistive robots designed for and evaluated by persons with dementia. Assistive robots that only increased mobility or brain-computer interfaces were excluded. Google Scholar, IEEE Digital Library, PubMed, and ACM Digital Library were searched. A final set of 53 articles covering research in 16 different countries are reviewed. Assistive robots are categorized into five different applications and evaluated for their effectiveness, as well as the robots’ social and emotional capabilities. Our findings show that robots used in the context of therapy or for increasing engagement received the most attention in the literature, whereas the robots that assist by providing health guidance or help with an activity of daily living received relatively limited attention. PARO was the most commonly used robot in dementia care studies. The effectiveness of each assistive robot and the outcome of the studies are discussed, and particularly, the social/emotional capabilities of each assistive robot are summarized. Gaps in the research literature are identified and we provide directions for future work.
Computer-based virtual laboratory simulations: LabHEART cardiac physiology practical
Authors: Monteiro Olivia , Bhaskar Anand , Ng Anna K. M. , Murdoch Colin E. , Baptista-Hon Daniel T.
Published: September 2021

Practical demonstration of cardiomyocyte function requires substantial preparation, a source of freshly isolated animal hearts, and specialized equipment. Even where such resources are available, it is not conducive for demonstration to any more than a few students at a time. These approaches are also not consistent with the 3R principle (replacement, reduction, and refinement) of ethical use of animals. We present an implementation of the LabHEART software, developed by Donald Bers and Jose Puglisi, for medical students. Prior to the activity, students had lectures covering the physiological and pharmacological aspects of cardiac excitation-contraction (EC) coupling. We used this problem-based activity to help students consolidate their knowledge and to allow a hands-on approach to explore the key features of EC coupling. Students simulate and measure action potentials, intracellular calcium changes, and cardiomyocyte contraction. They also apply drugs that target ion channels (e.g., nifedipine or tetrodotoxin) or sympathetic input (using isoproterenol) and explore changes to EC coupling. Furthermore, by modifying the biophysical parameters of key ion channels involved in the electrical activity of the heart, students also explore the effect of channelopathies such as long QT syndromes. We describe approaches to implement this activity in a flipped classroom format, with recorded lecture materials provided ahead of the practical to facilitate active learning. We also describe our experiences implementing this activity online. The content and difficulty of the activity can be altered to suit individual courses and is also amenable to promote peer-driven learning.
Urban Planning Image Feature Enhancement and Simulation Based on Partial Differential Equation Method
Authors: Li Duo
Published: September 2021

Based on the introduction of the basic ideas and related technologies of partial differential equations, as well as the method of path planning, the application of partial differential equations in solving urban path planning is studied. The path planning model of partial differential equations and the setting of obstacle boundary conditions are introduced, and adaptive. Theoretical research and experimental results show that it is feasible and effective to solve urban path planning by partial differential equations, which provides a new way for urban path planning research ideas and methods. This paper proposes an image detection algorithm based on diffusion equation. According to the logarithmic transformation, the multiplicative speckle noise in the image can be converted into additive noise. We first perform logarithmic transformation on the image and then use the denoising model of the diffusion equation to filter out the noise in the image and then use the logarithm to recognize the image. The difference image is obtained by the domain difference method, and finally, the difference image is classified by the clustering algorithm, and the change area is extracted. Experiments show that the algorithm can effectively reduce the effect of multiplicative speckle noise on the change detection results, improve the accuracy of change detection, and shorten the change detection time. This article takes the path planning problem of a two-dimensional space city as an example to discuss the application of partial differential equations. According to the principle of energy conservation, this paper uses the two-dimensional space radiant heat conduction equation as an example to model and illustrate the solution of the path planning problem.
HIF‐1α Activation Promotes Luteolysis by Enhancing ROS Levels in the Corpus Luteum of Pseudopregnant Rats
Authors: Tang Zonghao , Chen Jiajie , Zhang Zhenghong , Bi Jingjing , Xu Renfeng , Lin Qingqiang , Wang Zhengchao
Published: September 2021

The increase of oxidative stress is one of the important characteristics of mammalian luteal regression. Previous investigations have revealed the essential role of reactive oxygen species (ROS) in luteal cell death during luteolysis, while it is unknown how ROS is regulated in this process. Considering the decrease of blood flow and increase of PGF2α during luteolysis, we hypothesized that the HIF‐1α pathway may be involved in the regulation of ROS in the luteal cell of the late corpus luteum (CL). Here, by using a pseudopregnant rat model, we showed that the level of both HIF‐1α and its downstream BNIP3 was increased during luteal regression. Consistently, we observed the increase of autophagy level during luteolysis, which is regulated in a Beclin1‐independent manner. Comparing with early (Day 7 of pseudopregnancy) and middle CL (Day 14), the level of ROS was significantly increased in late CL, indicating the contribution of oxidative stress in luteolysis. Inhibition of HIF‐1α by echinomycin (Ech), a potent HIF‐1α inhibitor, ameliorated the upregulation of BNIP3 and NIX, as well as the induction of autophagy and the accumulation of ROS in luteal cells on Day 21 of pseudopregnancy. Morphologically, Ech treatment delayed the atrophy of the luteal structure at the late‐luteal stage. An in vitro study indicated that inhibition of HIF‐1α can also attenuate PGF2α‐induced ROS and luteal cell apoptosis. Furthermore, the decrease of cell apoptosis can also be observed by ROS inhibition under PGF2α treatment. Taken together, our results indicated that HIF‐1α signaling is involved in the regression of CL by modulating ROS production via orchestrating autophagy. Inhibition of HIF‐1α could obviously hamper the apoptosis of luteal cells and the process of luteal regression.
A Decomposition-Based Multiobjective Optimization Evolutionary Algorithm with Adaptive Weight Generation Strategy
Authors: Fu Guo-Zhong , Yu Tianda , Li Wei , Deng Qiang , Yang Bo
Published: September 2021

Multiobjective evolutionary algorithm based on decomposition (MOEA/D) is the seminal framework of multiobjective evolutionary algorithms (MOEAs). To alleviate the nonuniformly distributed solutions generated by a fixed set of evenly distributed weight vectors in the presence of nonconvex and disconnected problems, an adaptive vector generation mechanism is proposed. A coevolution strategy and a vector generator are synergistically cooperated to remedy the weight vectors. Optimal weight vectors are generated to replace the useless weight vectors to assure that optimal solutions are distributed evenly. Experiment results indicate that this mechanism is efficient in improving the diversity of MOEA/D.
Evaluation of the Findings of Patients Who Underwent Sutureless Flanged Transconjunctival Intrascleral Intraocular Lens Implantation with or without Pars Plana Vitrectomy
Authors: Suren Elcin , Kalayci Mustafa , Cetinkaya Ersan , Kucuk Mehmet Fatih , Dogan Mehmet Erkan , Durmaz Doğan , Duman Fulya , Erol Muhammet Kazim
Published: September 2021

Purpose. To compare the visual outcomes and complications of patients who underwent flanged transconjunctival sutureless intrascleral intraocular lens (SIS IOL) implantation after anterior and pars plana vitrectomy. Methods. All patients who underwent flanged transconjunctival SIS IOL fixation using a 27-gauge needle between September 2017 and November 2019 and were followed up for at least six months were evaluated. The cases in which anterior vitrectomy was performed were classified as Group 1, and those that underwent pars plana vitrectomy were classified as Group 2. The best-corrected visual acuity (BCVA), spherical equivalent values, corneal endothelial cell density, and intraocular pressures were compared between the two groups before and after the operation. Intraoperative and postoperative complications were assessed. Results. The study included 108 eyes of 108 patients who were included in the study. Group 1 consisted of 48 patients and Group 2 comprised of 60 patients. When the findings between Groups 1 and 2 were compared in the postoperative period, there was no statistically significant difference in terms of the mean intraocular pressure increase, endothelial cell density, BCVA, and spherical equivalent value (

P
=
0.818

, 0.601, 0.368, and 0.675, respectively). When all the patients were considered as a single group, the mean spherical value at the sixth postoperative month was 0.3 ± 2.2 D (min-max, (−5.5)–(+6)), the mean cylindrical value was −1.7 ± 2.4 D (min-max, (−9.25)–(+4)), and the mean spherical equivalent value was −0.5 ± 2.3 D (min-max, (−6.5)–(+6)). Conclusion. The flanged transconjunctival SIS IOL fixation technique performed using a 27-gauge needle is safe and effective in the patient group with aphakia and lens/IOL dislocation or subluxation. However, in patients planned to undergo flanged transconjunctival SIS IOL implantation, pars plana vitrectomy seems to be a more suitable option than anterior vitrectomy to reduce complications.