Psychological Impacts of the COVID-19 Outbreak on Chinese International Students: Examining Prevalence and Associated Factors

Background: As the international community has grappled to bring the corona virus disease 2019 (COVID-19) under control, many social factors have emerged and unbearable pressure has been placed on us all. This study aimed to explore the psychological symptoms and influencing factors of the pandemic on Chinese international students. Method: Post-Traumatic Stress Disorder (PTSD) symptoms and other psychological symptoms were investigated using the PTSD Checklist Civilian Version (PCL-C) and the Depression, Anxiety, Stress Scale-21 (DASS-21). Demographic data and data pertaining to the impact of COVID-19 on Chinese international students was also collected.Result: Chinese international students in their fourth year of university education showed higher depressive symptoms, anxiety symptoms, and stress symptoms than students in other years of their degree programs. Each of these psychological symptoms were higher for Chinese international students in high school than for students in their first and second years of university education. Chinese international students who were abroad were found to be most anxious about the risk of infection, financial stress, and travel restrictions following the COVID-19 outbreak.Conclusion: Our study suggest that the effect of COVID-19 on Chinese international students’ psychological symptoms are significant. Our results are valuable for legislators and healthcare providers, who may need to develop effective psychological interventions for Chinese international students

EVALUATING MICROWAVE BREAST IMAGES

INTRODUCTION Microwave imaging shows potential in medical applications such as tracking breast tumors [1]. It is advantageous over some of the other modalities such as MRI due to its relatively low cost, non-ionizing nature, and non-invasiveness [1]. The Tissue Sensing Adaptive Radar (TSAR) system is developed for microwave breast imaging and acquires reflected signals as an antenna scans the subject at a number of locations [2]. Then, the data is processed and an image is formed using a delay and sum focusing method [2]. The TSAR imaging algorithm involves many parameters, but the effect of each parameter on the image is unclear. Some parameters, such as wave speed (related to permittivity), are difficult to estimate and often inaccurate. A lack of objective image evaluation metrics makes it difficult to determine the magnitude of the effect of a parameter. The structural similarity (SSIM) index is a tool for objective image quality assessment [3]. It is known for its simplicity and relevance to the human visual system [3]. The SSIM index evaluates how similar two images are by modelling the difference as a weighted product of three independent parameters: luminance, contrast, and structure [3]. This study evaluates if the SSIM index is a suitable metric for evaluating microwave breast images. The dominance of each component of the SSIM Index is also investigated. METHODS In this study, the effectiveness of the SSIM index is evaluated by changing parameters in the TSAR imaging algorithm, then comparing the image produced to the known reference image using the built-in MATLAB ssim function. Both simulated data and experimental data are investigated. Parameters investigated include wave speed in different regions (using permittivity) and different methods to reduce the dominant reflection from the skin. RESULTS The SSIM index is observed to be indicative of the degree of similarities in microwave images. In the cases tested, structure generally has been the most dominant component while contrast is often the least dominant component (Figure 1). Maps of local SSIM index, luminance, contrast, and structure values proved useful in identifying areas of change.The SSIM index indicated that skin permittivity has the least effect on imaging while interior permittivity is important to be within 10-15%. These observations match expectations. DISCUSSION AND CONCLUSIONS The SSIM index looks promising as a suitable image quality metric for microwave breast imaging. It provides an objective and numerical method of evaluating similarity and change between different microwave images. In the future, an improved SSIM index could help identify the effect of some parameters in the TSAR algorithm and optimize the imaging process

Multi-grained Evidence Inference for Multi-choice Reading Comprehension

Multi-choice Machine Reading Comprehension (MRC) is a major and challenging task for machines to answer questions according to provided options. Answers in multi-choice MRC cannot be directly extracted in the given passages, and essentially require machines capable of reasoning from accurate extracted evidence. However, the critical evidence may be as simple as just one word or phrase, while it is hidden in the given redundant, noisy passage with multiple linguistic hierarchies from phrase, fragment, sentence until the entire passage. We thus propose a novel general-purpose model enhancement which integrates multi-grained evidence comprehensively, named Multi-grained evidence inferencer (Mugen), to make up for the inability. Mugen extracts three different granularities of evidence: coarse-, middle- and fine-grained evidence, and integrates evidence with the original passages, achieving significant and consistent performance improvement on four multi-choice MRC benchmarks.Comment: Accepted by TASLP 2023, vol. 31, pp. 3896-390

Fluctuations in population size of Theileria orientalis Ikeda within the tick vector Haemaphysalis longicornis Neumann : an investigation into the life cycle of T. orientalis Ikeda : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Science in Zoology, Massey University, Palmerston North, New Zealand

Figures are re-used with publishers' permission.Theileria orientalis Ikeda is a protozoan parasite of cattle that causes disease through the destruction of the host's erythrocytes. In 2012, the parasite caused an epidemic of bovine theileriosis in New Zealand at great economic cost to the farming community. As a result, a large number of scientific studies have been undertaken to understand the epidemiology of the T. orientalis Ikeda parasite in the hopes of mitigating the damage done by the parasite. An essential part of the epidemiology of any pathogen is the understanding of its life cycle and this holds true with T. orientalis Ikeda which, like other Theileria parasites, exhibits a complex life cycle involving multiple hosts. In this thesis, fluctuations of T. orientalis Ikeda populations within nymph tick hosts were investigated over the course of six months. By doing so, this investigation highlights a part of the T. orientalis Ikeda lifecycle that is poorly covered in the scientific literature. The population of T. orientalis Ikeda within the tick was determined through qPCR analysis. Analysis of the qPCR results found that populations of T. orientalis Ikeda fluctuated greatly within the ticks over the course of six months. Ticks infected with Theileria were procured through the development of a novel mass tick- rearing protocol: the artificial infestation of a cattle-beast with naïve ticks through the fixation of tick-containing ear-bags. A pilot study of the protocol showed that the fixation of ear-bags onto cattle using Kamar® adhesive did not negatively impact the welfare of the cattle involved. The subsequent field trial of the protocol resulted in the successful engorgement and infection of five thousand naïve tick larva. These results demonstrated a viable method to obtain T. orientalis Ikeda infected ticks that would be suitable for further research. Also described in detail in this thesis are attempts at adapting the protocol of Krober and Guerin (2007) to create a silicone membrane for the artificial feeding of tick larvae on Theileria-infected blood without the involvement of live hosts. Despite multiple attempts, the experiments yielded no successful attachments of ticks onto the synthetic membranes. Failure here was attributed largely to the adapted protocol creating silicone membranes that were too thick for the larval ticks to successfully penetrate with their mouthparts. However, the in vitro feeding of ticks presents itself as a great potential contributor to future tick research. It is hoped that the knowledge gained from the repeated trials of the in vitro feeding apparatus in this experiment may help in the development of successful protocols in the future

Dissecting the Bond Formation Process of d10d^{10}-Metal-Ethene Complexes with Multireference Approaches

The bonding mechanism of ethene to a nickel or palladium center is studied by the density matrix renormalization group algorithm, the complete active space self consistent field method, coupled cluster theory, and density functional theory. Specifically, we focus on the interaction between the metal atom and bis-ethene ligands in perpendicular and parallel orientations. The bonding situation in these structural isomers is further scrutinized using energy decomposition analysis and quantum information theory. Our study highlights the fact that when two ethene ligands are oriented perpendicular to each other, the complex is stabilized by the metal-to-ligand double-back-bonding mechanism. Moreover, we demonstrate that nickel-ethene complexes feature a stronger and more covalent interaction between the ligands and the metal center than palladium-ethene compounds with similar coordination spheres.Comment: 13 pages, 9 figure

Evaluation of corrosion expansion of reinforced concrete specimen using fiber optical Brillouin sensing technique

This paper investigated the evaluation of the concrete damage degree due to steel bar corrosion for reinforced concrete structures. Brillouin optical fiber time domain analysis (BOTDA) sensors were developed to monitor the steel bar corrosion expansion strain. Electrochemical accelerating experimental results showed the sensors could be used for early detection and the lifelong monitoring. The damage factor was proposed to quantitatively evaluate the concrete damage degree before initial cracking and during the development of cracks. Finite element analysis was performed on concrete specimens to map the monitoring results with the damage factor, which supported the capability of the damage factor