Manipulation of Skyrmion Motion Dynamics for Logical Device Application Mediated by Inhomogeneous Magnetic Anisotropy

Magnetic skyrmions are promising potential information carriers for future spintronic devices owing to their nanoscale size, non-volatility and high mobility. In this work, we demonstrate the controlled manipulation of skyrmion motion and its implementation in a new concept of racetrack logical device by introducing an inhomogeneous perpendicular magnetic anisotropy (PMA) via micromagnetic simulation. Here, the inhomogeneous PMA can be introduced by a capping nano-island that serves as a tunable potential barriers/well which can effectively modulate the size and shape of isolated skyrmion. Using the inhomogeneous PMA in skyrmion-based racetrack enables the manipulation of skyrmion motion behaviors, for instance, blocking, trapping or allowing passing the injected skyrmion. In addition, the skyrmion trapping operation can be further exploited in developing special designed racetrack devices with logic AND and NOT, wherein a set of logic AND operations can be realized via skyrmion–skyrmion repulsion between two skyrmions. These results indicate an effective method for tailoring the skyrmion structures and motion behaviors by using inhomogeneous PMA, which further provide a new pathway to all-electric skyrmion-based memory and logic devices.

Thriving in Graduate School as an International Student: How to Combat the Hidden Costs and Barriers

International students face various hidden costs that pose potential barriers to thriving in graduate school. In this chapter, we lay out several types of hidden costs: (1) higher expenses and time needed for the international status, (2) adjusting to living in a new country and its cultural differences, and (3) biases and racism. We emphasize that the success and happiness of international students depend on the department and the committee’s understanding of these hidden costs. We highlight strategies that international students can take as well as point-by-point advice for the supporters of international students.

On Theoretical and Numerical Aspects of Bifurcations and Hysteresis Effects in Kinetic Energy Harvesters

The piezoelectric energy-harvesting system with double-well characteristics and hysteresis in the restoring force is studied. The proposed system consists of a bistable oscillator based on a cantilever beam structure. The elastic force potential is modified by magnets. The hysteresis is an additional effect of the composite beam considered in this system, and it effects the modal solution with specific mass distribution. Consequently, the modal response is a compromise between two overlapping, competing shapes. The simulation results show evolution in the single potential well solution, and bifurcations into double-well solutions with the hysteretic effect. The maximal Lyapunov exponent indicated the appearance of chaotic solutions. Inclusion of the shape branch overlap parameter reduces the distance between the external potential barriers and leads to a large-amplitude solution and simultaneously higher voltage output with smaller excitation force. The overlap parameter works in the other direction: the larger the overlap value, the smaller the voltage output. Presumably, the successful jump though the potential barrier is accompanied by an additional switch between the corresponding shapes.

Enhanced terahertz detection of multigate graphene nanostructures

Terahertz (THz) waves have revealed a great potential for use in various fields and for a wide range of challenging applications. High-performance detectors are, however, vital for exploitation of THz technology. Graphene plasmonic THz detectors have proven to be promising optoelectronic devices, but improving their performance is still necessary. In this work, an asymmetric-dual-grating-gate graphene-terahertz-field-effect-transistor with a graphite back-gate was fabricated and characterized under illumination of 0.3 THz radiation in the temperature range from 4.5 K up to the room temperature. The device was fabricated as a sub-THz detector using a heterostructure of h-BN/Graphene/h-BN/Graphite to make a transistor with a double asymmetric-grating-top-gate and a continuous graphite back-gate. By biasing the metallic top-gates and the graphite back-gate, abrupt n+n (or p+p) or np (or pn) junctions with different potential barriers are formed along the graphene layer leading to enhancement of the THz rectified signal by about an order of magnitude. The plasmonic rectification for graphene containing np junctions is interpreted as due to the plasmonic electron-hole ratchet mechanism, whereas, for graphene with n+n junctions, rectification is attributed to the differential plasmonic drag effect. This work shows a new way of responsivity enhancement and paves the way towards new record performances of graphene THz nano-photodetectors.

Creative Pedagogy for Literacy Instruction

This chapter intends to provide a definition for the multi-faceted concept of creativity, describe components of the creative process, identify potential barriers to nurturing creativity, and present an explanation of creative pedagogy. The author believes that the pervasiveness of literacy in all subject matter provides an ideal mechanism for training preservice teachers in creative pedagogy. Throughout the chapter, the reader will find descriptions of activities that promote creativity through literacy instruction and examples of creative pedagogy in a preservice teacher education course.

Evaluation of hybrid threats to DU technologies transfer

An object of this research is to evaluate the premises of transfer of dual use technologies appeared in Ukraine and other CIS countries. It aims to highlight a hybrid impact of political, historical and other potential barriers faced between technology offeror/recipient nowadays. The investigated problem. Apart from the highlighted affect of political, historical and other potential barriers faced between technology supplier /recipient these days, the paper also discusses how the covid pandemic and democracy crisis on the global joined to and affect an efficiency, proper functioning and transparency of technology transfer process. The experience and practice show that the process of technology transfer is rather complicated, multi-leveled and involves more than two players. It is impacted with and follows few factors and conditions that constrain its success or failure at the end. It was shown that the development of dual use technologies continues in a quagmire of conflicting interests, in light of discussed factors therein, national security and export control rationales. For the time being, debates on dual use (DU) technologies and their misuse lack creativity and rather dim; political and diplomatic initiatives came finally to nowhere trying to find turnkey solutions, thus the discussed set of factors affecting the efficient transfer and strategic export control, is quite a challenge nowadays. The main scientific results. The discussed therein factors imply the hybrid threat to transfer of technologies, closely interrelated and possess a profound significance, tho. From today and forward each step towards optimization of transfer should be carried out considering all groups and specifics of high level of science intensity of advanced technologies. Ukraine being a country with still transitional (from socialist to capitalist) type of economy, a mechanism for IP protection with regard to their scientific and technical results providing this necessary level of science intensity of technology, in the analyzed period of time has not yet been properly worked out and not enshrined in bylaws. The result of this eresearch makes a solid background for further debates as to technology transfer in terms of political science and export control

THE AMMONIA VAPORS INFLUENCE ON THE ELECTRICAL CHARACTERISTICS OF NANOSIZED TIN DIOXIDE FILMS OBTAINED USING A POLYMER

In the presented paper the effect of ammonia vapors on the electrical properties of nanosized tin dioxide films obtained using polymers was investigated to assess the possibility of their use as an ammonia sensor’s sensitive element at room temperature. Ammonia vapor leads to a decrease in the conductivity of the studied SnO2 films. This is due to the fact that the adsorbed ammonia molecules increase the height of the intergranular potential barriers, and the surface shut-off bend of the energy bands. The main role in this is played by the processes of physical adsorption of ammonia molecules. The sensitivity of the films to ammonia vapor is in the range of 0.35-0.63 and reaches a maximum at a voltage of 300 V. The processes of adsorption and desorption take place in two stages and are reversible, as evidenced by the calculated time constants of adsorption and desorption.

Innovative Patient Involvement During Covid-19: Keeping Patients at the Heart of HTA

The COVID-19 pandemic and lockdown measures in the United Kingdom resulted in significant challenges and created opportunities for innovation to keep patients at the heart of HTA. The introduction of the Coronavirus Act 2020 and the associated public health guidance meant that NICE's conventional HTA methods were no longer feasible. NICE introduced rapid, innovative updates to patient and public involvement (PPI), decision-making meetings, and consultations to harness the expertise of patients and the public to ensure guidance addressed the expected concerns and identified barriers which could impact access. This article describes the PPI support for NICE's rapid shift to virtual meetings and virtual engagement. We utilize the authors' experience and patient and public contributor feedback to understand the experience of participating in a virtual setting and identify four themes: accessibility; inclusivity; transparency; and intrapersonal relationships and committee dynamics. The article also considers how patient representatives participated in, and facilitated, the development of guidance for a hypothetical technology to keep patients and the public at the heart of expedited and novel HTA processes to identify and understand the expected patient concerns and potential barriers for when a technology would be introduced.

Library Staff Need More Support in Order to Alleviate Teaching Anxiety

A Review of: Lundstrom, K., Fagerheim, B. & Van Geem, S. (2021). Library teaching anxiety: Understanding and supporting a persistent issue in librarianship. College & Research Libraries, 82(3), 389-409. https://doi.org/10.5860/crl.82.3.389 Abstract Objective – To determine academic librarians’ attitudes towards their teaching, how teaching anxiety manifests itself, and how teaching anxiety affects these attitudes. Design – Online Survey. Setting – The survey was distributed through various library science listservs. Subjects – Any library staff with a teaching component in their role were invited to respond. There was a total of 1,035 initial responses. Methods – The survey questions were based on a previously published survey about teaching anxiety by Davis (2007). However, the survey for this study added questions about formal and self-diagnosis of other types of anxieties, physical and psychological anxiety symptoms, and how teaching anxiety impacts other areas of the respondents’ lives. There were also questions on potential supports to reduce teaching anxiety, as well as potential barriers to these supports. Main Results – It was found that approximately 65% of respondents experience teaching anxiety. Approximately 40% of those respondents were formally diagnosed with anxiety, and approximately 42% were self-diagnosed. There was a significant association between a formal diagnosis of anxiety, and teaching anxiety. There were also significant associations between past training, preparation, and teaching anxiety, with anxiety occurring less with increased training and preparation. Conclusion – Teaching anxiety is a significant issue among library staff. Supports in the form of workshops on teaching as well as coping with anxiety can possibly help to reduce this phenomenon.

Assessing the perception of stakeholders regarding the impact of coastal tourism on the environment in the Romanian Black Sea coastal area

The coastal and marine area is one of an endlessly increasing number of human activities and provisions, the most significant of which are those associated with tourism. With the start of the MARSPLAN BS-II project in 2019, the planning of public participation actions of stakeholders to identify areas and important features for each maritime activity to develop and implement MSP has started. This study, using an appropriate exploratory approach, namely Grounded Theory, aims to assess stakeholders' perceptions of the environmental impact of tourism in the Romanian Black Sea coastal area to identify potential barriers that may arise from the perspective of implementing the Black Sea MSP. Even if the impact of tourism on the environment cannot be studied in-depth and fully proven, it is obvious, through our results, that tourism should fully enjoy the management and planning efforts.