Faculty COVID-19 Reflection 5

As part of its documentation for Spring 2020 Faculty Development Workshop attendance, Faculty Commons requested that attendees share their reflections on the workshop content. Faculty were also asked to document the impact that COVID-19 and the switch to online instruction has had on their teaching and professional duties during the Spring 2020 semester

Evidence of a compensated semimetal with electronic correlations at the CNP of twisted double bilayer graphene

Recently, magic-angle twisted bilayer graphene (MATBLG) has shown the emergence of various interaction-driven novel quantum phases at the commensurate fillings of the moir'e superlattice, while the charge neutrality point (CNP) remains mostly a vanilla insulator. Here, we show an emerging phase of nearly compensated semimetallicity at the CNP of twisted double bilayer graphene (TDBLG), a close cousin of MATBLG, with signatures of electronic correlation. Using electrical and thermal transport, we find almost two orders of magnitude enhancement of the thermopower in magnetic fields much smaller than the extreme quantum limit, accompanied by a large magnetoresistance($\sim 2500\%$) at CNP. This provides indisputable experimental evidence that TDBLG near CNP is a compensated semimetal. Moreover, at low temperatures, we observe an unusual sublinear temperature dependence of resistance. A recent theory predicts the formation of an excitonic metal near CNP, where small electron and hole pockets coexist. We understand the sublinear temperature dependence in terms of critical fluctuations in this theory

Biocontrol of larval mosquitoes by Acilius sulcatus (Coleoptera: Dytiscidae)

<p>Abstract</p> <p>Background</p> <p>Problems associated with resistant mosquitoes and the effects on non-target species by chemicals, evoke a reason to find alternative methods to control mosquitoes, like the use of natural predators. In this regard, aquatic coleopterans have been explored less compared to other insect predators. In the present study, an evaluation of the role of the larvae of <it>Acilius sulcatus </it>Linnaeus 1758 (Coleoptera: Dytiscidae) as predator of mosquito immatures was made in the laboratory. Its efficacy under field condition was also determined to emphasize its potential as bio-control agent of mosquitoes.</p> <p>Methods</p> <p>In the laboratory, the predation potential of the larvae of <it>A. sulcatus </it>was assessed using the larvae of <it>Culex quinquefasciatus </it>Say 1823 (Diptera: Culicidae) as prey at varying predator and prey densities and available space. Under field conditions, the effectiveness of the larvae of <it>A. sulcatus </it>was evaluated through augmentative release in ten cemented tanks hosting immatures of different mosquito species at varying density. The dip density changes in the mosquito immatures were used as indicator for the effectiveness of <it>A. sulcatus </it>larvae.</p> <p>Results</p> <p>A single larva of <it>A. sulcatus </it>consumed on an average 34 IV instar larvae of <it>Cx. quinquefasciatus </it>in a 24 h period. It was observed that feeding rate of <it>A. sulcatus </it>did not differ between the light-on (6 a.m. – 6 p.m.), and dark (6 p.m. – 6 a.m.) phases, but decreased with the volume of water i.e., space availability. The prey consumption of the larvae of <it>A. sulcatus </it>differed significantly (P < 0.05) with different prey, predator and volume combinations, revealed through univariate ANOVA. The field study revealed a significant decrease (p < 0.05) in larval density of different species of mosquitoes after 30 days from the introduction of <it>A. sulcatus </it>larvae, while with the withdrawal, a significant increase (p < 0.05) in larval density was noted indicating the efficacy of <it>A. sulcatus </it>in regulating mosquito immatures. In the control tanks, mean larval density did not differ (p > 0.05) throughout the study period.</p> <p>Conclusion</p> <p>the larvae of the dytiscid beetle <it>A. sulcatus </it>proved to be an efficient predator of mosquito immatures and may be useful in biocontrol of medically important mosquitoes.</p

Burden of severe maternal morbidity and association with adverse birth outcomes in sub-Saharan Africa and south Asia: protocol for a prospective cohort study

Objectives The AMANHI morbidity study aims to quantify and describe severe maternal morbidities and assess their associations with adverse maternal, fetal and newborn outcomes in predominantly rural areas of nine sites in eight South Asian and sub-Saharan African countries. Methods AMANHI takes advantage of on-going population-based cohort studies covering approximately 2 million women of reproductive age with 1- to 3-monthly pregnancy surveillance to enrol pregnant women. Morbidity information is collected at five follow-up home visits - three during the antenatal period at 24-28 weeks, 32-36 weeks and 37+ weeks of pregnancy and two during the postpartum period at 1-6 days and after 42-60 days after birth. Structured- questionnaires are used to collect self-reported maternal morbidities including hemorrhage, hypertensive disorders, infections, difficulty in labor and obstetric fistula, as well as care-seeking for these morbidities and outcomes for mothers and babies. Additionally, structured questionnaires are used to interview birth attendants who attended women's deliveries. All protocols were harmonised across the sites including training, implementation and operationalising definitions for maternal morbidities. Importance of the AMANHI morbidity study Availability of reliable data to synthesize evidence for policy direction, interventions and programmes, remains a crucial step for prioritization and ensuring equitable delivery of maternal health interventions especially in high burden areas. AMANHI is one of the first large harmonized population- based cohort studies being conducted in several rural centres in South Asia and sub-Saharan Africa, and is expected to make substantial contributions to global knowledge on maternal morbidity burden and its implications

Population-based rates, timing and causes of maternal deaths, stillbirths, and neonatal deaths in south Asia and sub-Saharan Africa: a multi-country prospective cohort study

BackgroundModelled mortality estimates have been useful for health programmes in low-income and middle-income countries. However, these estimates are often based on sparse and low-quality data. We aimed to generate high quality data about the burden, timing, and causes of maternal deaths, stillbirths, and neonatal deaths in south Asia and sub-Saharan Africa.MethodsIn this prospective cohort study done in 11 community-based research sites in south Asia and sub-Saharan Africa, between July, 2012, and February, 2016, we conducted population-based surveillance of women of reproductive age (15–49 years) to identify pregnancies, which were followed up to birth and 42 days post partum. We used standard operating procedures, data collection instruments, training, and standardisation to harmonise study implementation across sites. Verbal autopsies were done for deaths of all women of reproductive age, neonatal deaths, and stillbirths. Physicians used standardised methods for cause of death assignment. Site-specific rates and proportions were pooled at the regional level using a meta-analysis approach.FindingsWe identified 278 186 pregnancies and 263 563 births across the study sites, with outcomes ascertained for 269 630 (96·9%) pregnancies, including 8761 (3·2%) that ended in miscarriage or abortion. Maternal mortality ratios in sub-Saharan Africa (351 per 100 000 livebirths, 95% CI 168–732) were similar to those in south Asia (336 per 100 000 livebirths, 247–458), with far greater variability within sites in sub-Saharan Africa. Stillbirth and neonatal mortality rates were approximately two times higher in sites in south Asia than in sub-Saharan Africa (stillbirths: 35·1 per 1000 births, 95% CI 28·5–43·1 vs 17·1 per 1000 births, 12·5–25·8; neonatal mortality: 43·0 per 1000 livebirths, 39·0–47·3 vs 20·1 per 1000 livebirths, 14·6–27·6). 40–45% of pregnancy-related deaths, stillbirths, and neonatal deaths occurred during labour, delivery, and the 24 h postpartum period in both regions. Obstetric haemorrhage, non-obstetric complications, hypertensive disorders of pregnancy, and pregnancy-related infections accounted for more than three-quarters of maternal deaths and stillbirths. The most common causes of neonatal deaths were perinatal asphyxia (40%, 95% CI 39–42, in south Asia; 34%, 32–36, in sub-Saharan Africa) and severe neonatal infections (35%, 34–36, in south Asia; 37%, 34–39 in sub-Saharan Africa), followed by complications of preterm birth (19%, 18–20, in south Asia; 24%, 22–26 in sub-Saharan Africa).InterpretationThese results will contribute to improved global estimates of rates, timing, and causes of maternal and newborn deaths and stillbirths. Our findings imply that programmes in sub-Saharan Africa and south Asia need to further intensify their efforts to reduce mortality rates, which continue to be high. The focus on improving the quality of maternal intrapartum care and immediate newborn care must be further enhanced. Efforts to address perinatal asphyxia and newborn infections, as well as preterm birth, are critical to achieving survival goals in the Sustainable Development Goals era

A Value Sensitive Design Approach to Adolescent Mobile Online Safety

With the rise of adolescent smartphone use, concerns about teen online safety are also on the rise. A number of parental control apps are available for mobile devices, but adoption of these apps has been markedly low. To better understand these apps, their users, and design opportunities in the space of mobile online safety for adolescents, we have conducted four studies informed by the principles of Value Sensitive Design (VSD). In Study 1 (Chapter 2), we conducted a web-based survey of 215 parents and their teens (ages 13-17) using two separate logistic regression models (parent and teen) to examine the factors that predicted parental use of technical monitoring apps on their teens\u27 mobile devices. Both parent and teen models confirmed that low autonomy granting (e.g., authoritarian) parents were the most likely to use parental control apps. The teen model revealed additional nuances, indicating that teens who were victimized online and had peer problems were more likely to be monitored by their parents. Overall, increased parental control was associated with more (not fewer) online risks. In Study 2 (Chapter 3), we conducted a structured, qualitative feature analysis of 75 Android mobile apps designed for promoting adolescent online safety. We found that the available apps overwhelmingly supported parental control through restriction and monitoring over teen self-regulation or parental active mediation. In Study 3 (Chapter 4), we conducted a qualitative analysis of 736 reviews of 37 mobile online safety apps from Google Play that were publicly posted and written by teens. Our results indicate that teen ratings were significantly lower than that of parents with 76% of the teen reviews giving apps a single star. Teens felt that the apps were overly restrictive and invasive of their personal privacy, negatively impacting their relationships with their parents. For our final study (Chapter 5), we developed a mobile app prototype suggesting alternative designs for keeping teens safe online and conducted a user study which showed that parents and children (ages 10-17) both significantly preferred our new app design over existing parental control apps. Both parents and children reported that our VSD informed design is less privacy-invasive for children and would improve communication and trust relationship between them. Yet, more work needs to be done to improve approaches for risk detection and mediation that support online safety. In summary, this research will enable researchers and designers to create more effective solutions for teen online safety that will help promote more positive parent-teen relationships

A Time-of-Flight Mass Spectrometric Study of Multiphoton Dissociation and Ionization of Selected Atmospherically Important Compounds

The thesis is concerned with the dissociation and ionization dynamics of selected atmospherically significant volatile organic compounds. The primary objective is to investigate the various photochemical events that take place within these molecules upon multiphoton excitation in the ultraviolet region of the electromagnetic spectrum. The major process that takes place upon multiphoton excitation of molecules is ionization of the followed by its dissociation in to different fragments. However, many isomerization and rearrangement process can occur when the molecules are excited to the intermediate excited states and can be probed using multiphoton ionization. The new products formed due to isomerization or rearrangement further absorb photons in the ultraviolet region can undergo fragmentation and ionization.Thesis Submitted for the Degree of Doctor of Philosophy (Science) in Chemistry (Physical) by Arup Kumar Ghosh Department of Chemistry University of Calcutta 2014The research was conducted under CSIR project in the Physical Chemistry division of IACS under the supervision of Prof. Tapas Chakrabort

Using A Value Sensitive Design Approach To Promote Adolescent Online Safety On Mobile Platforms

With the rise of adolescent smart phone use, concerns about teen online safety are also on the rise. A number of parental control apps are available for mobile devices but adoption of these apps has been markedly low. To address this problem, I have already conducted a structured, qualitative feature analysis of 75 Android mobile apps designed for the purpose of promoting adolescent online safety. My advisor helped to develop a conceptual framework for Teen Online Safety Strategies (TOSS) and mapped our feature analysis results to this conceptual framework. Overall, I found that the available apps overwhelmingly supported parental control through restriction and monitoring over teen self-regulation or parental active mediation, which has been shown to be a more effective parenting approach. Next, I plan to conduct a web-survey based to confirm our hypotheses that the values promoted in the design of these apps (e.g., distrust, authoritarian parenting, etc.) are sub-optimal and do not cater to the needs of parents or teens (e.g., trust building, accountability, etc.), thus contributing to the low rate of adoption. Then I will develop a mobile app prototype suggesting alternative designs for keeping teens safe online. In summary, my research will enable the HCI social computing community to create more effective solutions to teen online safety that will help promote positive parent-teen relationships