Size-regulated group separation of CoFe2O4 nanoparticles using centrifuge and their magnetic resonance contrast properties

Magnetic nanoparticle (MNP)-based magnetic resonance imaging (MRI) contrast agents (CAs) have been the subject of extensive research over recent decades. The particle size of MNPs varies widely and is known to influence their physicochemical and pharmacokinetic properties. There are two commonly used methods for synthesizing MNPs, organometallic and aqueous solution coprecipitation. The former has the advantage of being able to control the particle size more effectively; however, the resulting particles require a hydrophilic coating in order to be rendered water soluble. The MNPs produced using the latter method are intrinsically water soluble, but they have a relatively wide particle size distribution. Size-controlled water-soluble MNPs have great potential as MRI CAs and in cell sorting and labeling applications. In the present study, we synthesized CoFe(2)O(4) MNPs using an aqueous solution coprecipitation method. The MNPs were subsequently separated into four groups depending on size, by the use of centrifugation at different speeds. The crystal shapes and size distributions of the particles in the four groups were measured and confirmed by transmission electron microscopy and dynamic light scattering. Using X-ray diffraction analysis, the MNPs were found to have an inverse spinel structure. Four MNP groups with well-selected semi-Gaussian-like diameter distributions were obtained, with measured T(2) relaxivities (r(2)) at 4.7 T and room temperature in the range of 60 to 300 mM(−1)s(−1), depending on the particle size. This size regulation method has great promise for applications that require homogeneous-sized MNPs made by an aqueous solution coprecipitation method. Any group of the CoFe(2)O(4) MNPs could be used as initial base cores of MRI T(2) CAs, with almost unique T(2) relaxivity owing to size regulation. The methodology reported here opens up many possibilities for biosensing applications and disease diagnosis. PACS: 75.75.Fk, 78.67.Bf, 61.46.D

Accelerated Psychosocial Aging: Japanese Expect Lower Life Satisfaction Earlier than U.S. Adults

The current study examined whether perceptions of change in life satisfaction vary by age and culture. Perceptions of past, present and future life satisfaction were examined in adults aged 33-79 from the Midlife in the United States (MIDUS; N = 4803) and from the Survey of Midlife in Japan (MIDJA; N=974). Age differences in perceived change in life satisfaction were similar across the two nations such that the younger adults perceived improvement and the older adults perceived decline from the past to present and from present to the future. Despite similarities in age-related patterns, however, perceptions of declining life satisfaction were observed at younger ages in midlife for the Japanese adults compared to the U.S. adults. Also, younger U.S. adults foresaw more improvement in their life satisfaction from the past to the future compared to younger Japanese adults. Similarly, older U.S. adults perceived a moderate decrease in trajectory of life satisfaction whereas older Japanese adults perceived a sharp decline. Findings suggest that cultural context plays a role in perceptions of change in well-being across adulthood

Accelerated Psychosocial Aging: Japanese Expect Lower Life Satisfaction Earlier than U.S. Adults

The current study examined whether perceptions of change in life satisfaction vary by age and culture. Perceptions of past, present and future life satisfaction were examined in adults aged 33-79 from the Midlife in the United States (MIDUS; N = 4803) and from the Survey of Midlife in Japan (MIDJA; N=974). Age differences in perceived change in life satisfaction were similar across the two nations such that the younger adults perceived improvement and the older adults perceived decline from the past to present and from present to the future. Despite similarities in age-related patterns, however, perceptions of declining life satisfaction were observed at younger ages in midlife for the Japanese adults compared to the U.S. adults. Also, younger U.S. adults foresaw more improvement in their life satisfaction from the past to the future compared to younger Japanese adults. Similarly, older U.S. adults perceived a moderate decrease in trajectory of life satisfaction whereas older Japanese adults perceived a sharp decline. Findings suggest that cultural context plays a role in perceptions of change in well-being across adulthood

Beyond the Vulnerabilities of Loneliness: The Protective Role of Social Resources against Daily Stress

Lonely individuals are more vulnerable to the harmful effects of everyday stressors. Yet, little work has examined potential protective factors that may reduce lonely individuals’ negative experiences of daily stress. Across three studies, this dissertation identifies the situations in daily life that are related to differences in well-being between lonely and non-lonely adults, as well as factors that may be protective against everyday stressors for lonely individuals' daily well-being. The first study used an ecological momentary assessment design to examine how loneliness was related to different facets of well-being (emotional and physical well-being) across varying social contexts. Results indicated that being with others (vs. being alone) was a positive experience for both lonely and non-lonely older adults (increased positive affect and energy and decreased tiredness); yet, lonely individuals also showed an increased negative affect. In addition, lonely older adults reported a greater increase in negative affect than non-lonely individuals following a stressful interaction (vs. no stressful interaction). The next two studies examined positive factors that may serve a buffering effect for lonely individuals’ greater reactivity to daily stress. In the second study, positive network quality buffered the adverse effects of negative social interactions on emotional well-being (positive and negative affect) for lonely older adults, but not non-lonely adults (Chapter 3). The third study examined a protective factor that can vary from day to day – the occurrence of positive events. Results revealed that experiencing a positive event on the same day as experiencing a stressor was only protective for lonely individuals, but not non-lonely individuals. Importantly, only daily positive social events (i.e., positive interpersonal exchange) were related to a blunted increase in daily negative affect, whereas daily positive non-social events (i.e., those not involving a social component such as daily uplift at work) didn’t show a protective effect. Together, findings from this dissertation expand our knowledge about the daily vulnerabilities of lonely individuals and further identify positive factors that protect against the harmful effects of everyday stressors. Results indicate that potentially modifiable resources, such as positive social networks and daily positive social events, may be important points of future interventions

College Students’ Perception and Concerns regarding Online Examination amid COVID-19

Growing concerns about online examinations have led to various investigations of techniques for improvement. With most higher education institutions shifting to online learning and examination amid COVID-19, these concerns, including the academic dishonesty, validity, reliability, and anxiety of online examination, are more critical than ever. This paper presents the outcomes of the survey to elicit the perceptions of undergraduate students from two universities in South Korea and Malaysia towards undertaking online exams and the associated concerns. Additionally, the study explores the potential of artificial intelligence (AI) in addressing these concerns. There are three main research questions: 1) How has AI been adopted to tackle the four main concerns in online exams? 2) What are the students’ perceptions regarding these concerns? Are there any differences between South Korean and Malaysian students? 3) What is the extent of the stress level when webcam proctoring and timers are implemented during online exams? The survey results show that both South Korean and Malaysian students agree that online exams make cheating more accessible than in-person exams. They also suggest that selecting questions randomly from a question bank could discourage cheating. Moreover, the study highlights that both groups of students experience moderate stress levels when webcam proctoring is used over Zoom during online exams, and they experience a high-stress level when timers are set for each question

Exploring the Use of a Voice-based Conversational Agent to Empower Adolescents with Autism Spectrum Disorder

Voice-based Conversational Agents (VCA) have served as personal assistants that support individuals with special needs. Adolescents with Autism Spectrum Disorder (ASD) may also benefit from VCAs to deal with their everyday needs and challenges, ranging from self-care to social communications. In this study, we explored how VCAs could encourage adolescents with ASD in navigating various aspects of their daily lives through the two-week use of VCAs and a series of participatory design workshops. Our findings demonstrated that VCAs could be an engaging, empowering, emancipating tool that supports adolescents with ASD to address their needs, personalities, and expectations, such as promoting self-care skills, regulating negative emotions, and practicing conversational skills. We propose implications of using of-the-shelf technologies as a personal assistant to ASD users in Assistive Technology design. We suggest design implications for promoting positive opportunities while mitigating the remaining challenges of VCAs for adolescents with ASD.N

Introduction of IoT-Based Surrogate Parameters in the Ex-Post Countermeasure of Industrial Sectors in Integrated Permit Policy

New approaches and techniques are required for environmental management in workplaces that emit pollutants. The best available techniques (BATs) that are suggested by the integrated environmental permit system (IEPS) play a pivotal role in providing state-of-the-art approaches and techniques to workplaces. For the workplaces that install facilities with the BATs, it is necessary to perform real-time monitoring to determine whether pollutant emission facilities and treatment facilities are operating normally and whether such facilities can maintain the optimal condition during the emission of pollutants. The environmental management measures used before the IEPS had limitations for workplaces that are subjected to integrated environmental management because they consider the entire workplace as a single pollution source by combining all media. In addition, only the emission concentrations and amounts of pollutants were monitored because only the points at which most pollutants are discharged, i.e., stacks for air pollutant emission facilities and final effluent outlets for water pollutant emission facilities, are monitored. These monitoring approaches in a variety of facilities involve considerable costs, and most of them (95% for stacks in workplaces under IEPS, Korea) cannot perform real-time observation even though some of them are capable of it (5% for stacks managed by Tele Monitoring System, TMS). In this study, the applicability of a wireless sensor monitoring network was examined as a new approach for environmental management in workplaces. Based on the sensor monitoring network, surrogate parameters that can indirectly monitor the critical operating factors of pollutant emission and prevention facilities were developed and then measured in real time to examine the status of these facilities. Surrogate parameters can be used instead of directly measuring pollutants as the former has high efficiency, such as cost reduction, and can provide reliable data on the emission characteristics of pollutants. The wireless network is based on an Internet of Things (IoT) platform under real-time conditions in the emission and production facilities in a workplace. This study suggested that a wireless network using the IoT platform improves the BAT assessment methodology to understand the efficiency of environmental pollution reduction and the economic contribution to the workplace

Subcutaneous emphysema and pneumomediastinum following orbital blowout pathological fracture in a cat with nasal lymphoma: a case report

Abstract Background Subcutaneous emphysema and pneumomediastinum are rare complications associated with orbital blowout pathological fracture. Case presentation A 7-year old, castrated male Abbysinian cat presented with anorexia, lethargy, nausea, eyelid swelling, nasal discharge, and sneezing. Based on the clinical and diagnostic work-up, the cat was diagnosed with T cell high-grade nasal lymphoma associated with orbital pathological fracture due to the tumour invasion. After chemotherapy, the cat showed massive subcutaneous emphysema from frontal region to abdomen and pneumomediastinum due to orbital blowout pathological fracture. As the nasal mass decreased in volume; the air had moved from the maxillary sinus to the subcutaneous region and the mediastinum through fascial planes in the head and neck region. Conclusions This is a first case report of a massive subcutaneous emphysema and pneumomediastinum due to an orbital blowout pathological fracture following chemotherapy in feline nasal lymphoma in veterinary medicine