Observation of intrinsic inverse spin Hall effect

We report observation of intrinsic inverse spin Hall effect in un-doped GaAs multiple quantum wells with a sample temperature of 10 K. A transient ballistic pure spin current is injected by a pair of laser pulses through quantum interference. By time-resolving the dynamics of the pure spin current, the momentum relaxation time is deduced, which sets the lower limit of the scattering time between electrons and holes. The transverse charge current generated by the pure spin current via the inverse spin Hall effect is simultaneously resolved. We find that the charge current is generated well before the first electron-hole scattering event. Generation of the transverse current in the scattering-free ballistic transport regime provides unambiguous evidence for the intrinsic inverse spin Hall effect.Comment: 4 pages, 3 figure

All-optical generation and detection of sub-picosecond ac spin current pulses in GaAs

Sub-picosecond ac spin current pulses are generated optically in GaAs bulk and quantum wells at room temperature and 90K through quantum interference between one-photon and two-photon absorptions driven by two phase-locked ultrafast laser pulses that are both circularly polarized. The dynamics of the current pulses are detected optically by monitoring in real time and real space nanoscale motion of electrons with high-resolution pump-probe techniques.Comment: 5 pages, 5 figure

Femtosecond Pump-Probe Studies of Reduced Graphene Oxide Thin Films

The dynamics of photocarriers in reduced graphene oxide thin films is studied by using ultrafast pump-probe spectroscopy. Time dependent differential transmissions are measured with sample temperatures ranging from 9 to 300 K. At each sample temperature and probe delay, the sign of differential transmission remains positive. A fast energy relaxation of hot carriers is observed, and is found to be independent of sample temperature. Our experiments show that the carrier dynamics in reduced graphene oxide is similar to other types of graphene, and that the differential transmission is caused by phase-state filling of carriers.Comment: 3 pages, 3 figure

Hot carrier diffusion in graphene

We report an optical study of charge transport in graphene. Diffusion of hot carriers in epitaxial graphene and reduced graphene oxide samples are studied using an ultrafast pump-probe technique with a high spatial resolution. Spatiotemporal dynamics of hot carriers after a point-like excitation are monitored. Carrier diffusion coefficients of 11,000 and 5,500 squared centimeters per second are measured in epitaxial graphene and reduced graphene oxide samples, respectively, with a carrier temperature on the order of 3,600 K. The demonstrated optical techniques can be used for non-contact and non-invasive in-situ detection of transport properties of graphene.Comment: 5 pages, 3 figure

Are we empowered? A qualitative approach to unfold the experiences of female nurses in Pakistan

The disparity of men and women in certain societies, such as Pakistan, is a growing concern. The disparity, unchanging mind-set, and definitions rooted in traditions do not free individuals from the socially bound gender identities. In such circumstances, educational institutions can become a way of transforming social structures. Considering female nurses in Pakistan as a case study, this paper explores the notion of “empowerment” and the factors responsible for empowerment or disempowerment of female nurses. The study also evaluates the role of a leading nursing institution in Pakistan namely the Aga Khan University- School of Nursing and Midwifery (AKUSONAM) in empowering female nurses. The data is collected through five focus group discussion among forty-five alumni of AKU-SONAM. The findings of the study presents an “inside-out” understanding of the term “empowerment” by female nurses of Pakistan and; enlists the challenges faced by women in Pakistan in becoming and working as nurses. The study also put forward recommendations for nursing professional bodies such as Pakistan Nursing Council and Pakistan Nursing Federation and other nursing institutions in Pakistan. The paper would serve as a guide to enhance further development in nursing and women empowerment

Trace element studies on Karachi populations Part V: Blood lead levels in normal healthy adults and grammar school children

Blood lead levels of healthy Karachi population were estimated. Mean levels for males, females, soldiers and school children were 34.4, 31.8, 29.9 and 38.2 micrograms/dl respectively. About 93% cases of either sex had elevated lead levels, of whom 30% males and 10% females had levels above the safety limits (40 micrograms/dl). Soldiers living in relatively pollution free area though had levels lower than the rest of the population but 91% had levels over 25 micrograms/dl and only two had acceptable levels. Ninety-two percent children showed levels above 25 micrograms/dl with a large number having levels over 40 micrograms/dl. A very small percentage had normal levels. Pollution by traffic exhaust was assumed to be the principal cause for these high levels

WINGS: Wellness Interventions for Nurses’ growth and selfcare study at Purdue University, US and UEL, UK

During the pandemic, a quasi-experimental study was designed to empirically test the effectiveness of SOPHIE intervention among palliative care nurses in US. Along with SOPHIE framework, the study also included Nurses’ Psychological Trauma (NPT) model (Foli, et al., 2021). Our study included N=94 nurses working in palliative care setting including long-term care, nursing homes and hospice setting. Intervention included four weekly blog writing with pre and post surveys. Findings showed significant improvement in subjective wellbeing of nurses. Narrative analysis of the four weekly blogs and post blog feedback demonstrated self-reflexivity on the part of participants. Participants shared blogs were helpful as it provided them a valuable opportunity to generate self-awareness and ability to share traumatic experiences while creating avenues for personal growth and wellbeing. Our preliminary data suggest that SOPHIE tool is an effective tool for self-reflexivity and create pathways for selfcare and wellbeing

Pan-urologic cancer genomic subtypes that transcend tissue of origin

AbstractUrologic cancers include cancers of the bladder, kidney, prostate, and testes, with common molecular features spanning different types. Here, we show that 1954 urologic cancers can be classified into nine major genomic subtypes, on the basis of multidimensional and comprehensive molecular characterization (including DNA methylation and copy number, and RNA and protein expression). Tissue dominant effects are first removed computationally in order to define these subtypes, which reveal common processes—reflecting in part tumor microenvironmental influences—driving cellular behavior across tumor lineages. Six of the subtypes feature a mixture of represented cancer types as defined by tissue or cell of origin. Differences in patient survival and in the manifestation of specific pathways—including hypoxia, metabolism, NRF2-ARE, Hippo, and immune checkpoint—can further distinguish the subtypes. Immune checkpoint markers and molecular signatures of macrophages and T cell infiltrates are relatively high within distinct subsets of each cancer type studied. The pan-urologic cancer genomic subtypes would facilitate information sharing involving therapeutic implications between tissue-oriented domains.</jats:p

Ambipolar diffusion of photo-excited carriers in bulk GaAs

The ambipolar carrier diffusion in bulk GaAs is studied by using an ultrafast pump-probe technique with a high spatial resolution. Carriers with a point-like spatial profile are excited by a tightly focused pump laser pulse. The spatiotemporal dynamics of the carriers are monitored by a time-delayed and spatially scanned probe pulse. Ambipolar diffusion coefficients are deduced from linear fits to the expansion of the area of the profiles, and are found to decrease from about 170~$\mathrm{cm}^2 \mathrm{s}^{-1}$ at 10 K to about 20~$\mathrm{cm}^2 \mathrm{s}^{-1}$ at room temperature. Our results are consistent with those deduced from the previously measured mobilities.Comment: 4 pages, 4 figure

Serum cholesterol in neonates and their mothers. a pilot study

Reports from the Aga Khan University indicate that 58% of 400 school children studied had undesirably high serum cholesterol levels. The present study was undertaken to determine whether the high cholesterol levels are present at birth and to determine the relationship between cord blood, maternal blood cholesterol and maternal diet. Cord blood from 58 neonates and fasting venous blood form 45 mothers were analyzed for total serum cholesterol. Mothers were interviewed regarding their usual diet during pregnancy. Mean cord blood cholesterol was 56.90 mg/dl (range 26 to 123 mg/dI). Mean maternal blood cholesterol was 232.4mg/dl (range 141-382 mg/dl). Mean maternal intake of cholesterol was 457 mg (recommended level _ 300 mg/day). There was no significant co-relation between cord blood cholesterol and maternal blood cholesterol or maternal intake of cholesterol. Eighteen percent of the mothers reported a strong family history of hypercholesterolemia and/or heart disease, but this genetic tendency was not observed in the blood cholesterol level at birth indicating that environmental factors namely diet may have a prime role in determining serum cholesterol levels in childhoo