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Mental health challenges are common following cancer diagnosis, negatively impacting treatment and quality of life for breast cancer (BC) patients. This pilot study provides an understanding of the impacts of BC diagnosis and care experiences on the mental health of patients seen at the Aga Khan University Hospital in Nairobi, Kenya. We conducted 40 in-depth interviews, including 10 women with newly diagnosed BC, 10 women with metastatic BC, 10 family members and 10 healthcare professionals. Data were transcribed, translated into English as needed and coded using Dedoose software. Following BC diagnosis, it was reported that patients faced various physical, social, psychological and spiritual factors affecting their mental health and quality of life. Our interviews with each group indicated that BC patients experienced feelings of stress, anxiety and depression related to treatments and accompanying side effects. Disclosure concerns, financial impacts, relationship strain and negative outlooks on life were common among BC patients. The findings indicate that BC diagnosis and care experiences influence mental health in this population. With this basis, understanding and addressing the mental health challenges of BC patients is crucial to improve mental health and quality of life.
Between May and June 2021, healthcare personnel at two long-term care facilities underwent SARS-CoV-2 anti-nucleocapsid immunoglobulin G testing and completed a survey on COVID-19 exposures and symptoms. Antibody positivity rate was 8.9%. Similar rates of COVID-19 exposure occurred in non-occupational and occupational settings, with high self-reported adherence to workplace infection prevention practices.
The long-term cumulative impact of exposure to childhood adversity is well documented. There is an increasing body of literature examining protective factors following childhood adversity. However, no known reviews have summarised studies examining protective factors for broad psychosocial outcomes following childhood adversity.
Aims
To summarise the current evidence from longitudinal studies of protective factors for adult psychosocial outcomes following cumulative exposure to childhood adversity.
Method
We conducted a formal systematic review of studies that were longitudinal; were published in a peer-reviewed journal; examined social, environmental or psychological factors that were measured following a cumulative measure of childhood adversity; and resulted in more positive adult psychosocial outcomes.
Results
A total of 28 studies from 23 cohorts were included. Because of significant heterogeneity and conceptual differences in the final sample of articles, a meta-analysis was not conducted. The narrative review identified that social support is a protective factor specifically for mental health outcomes following childhood adversity. Findings also suggest that aspects of education are protective factors to adult socioeconomic, mental health and social outcomes following childhood adversity. Personality factors were protective for a variety of outcomes, particularly mental health. The personality factors were too various to summarise into meaningful combined effects. Overall GRADE quality assessments were low and very low, although these scores mostly reflect that all observational studies are low quality by default.
Conclusions
These findings support strategies that improve connection and access to education following childhood adversity exposure. Further research is needed for the roles of personality and dispositional factors, romantic relationship factors and the combined influences of multiple protective factors.
To characterize experiences, beliefs, and perceptions of risk related to coronavirus disease 2019 (COVID-19), infection prevention practices, and COVID-19 vaccination among healthcare personnel (HCP) at nonacute care facilities.
Design:
Anonymous survey.
Setting:
Three non–acute-care facilities in St. Louis, Missouri.
Participants:
In total, 156 HCP responded to the survey, for a 25.6% participation rate). Among them, 32% had direct patient-care roles.
Methods:
Anonymous surveys were distributed between April-May 2021. Data were collected on demographics, work experience, COVID-19 exposure, knowledge, and beliefs about infection prevention, personal protective equipment (PPE) use, COVID-19 vaccination, and the impact of COVID-19.
Results:
Nearly all respondents reported adequate knowledge of how to protect oneself from COVID-19 at work (97%) and had access to adequate PPE supplies (95%). Many HCP reported that wearing a mask or face shield made communication difficult (59%), that they had taken on additional responsibilities due to staff shortages (56%), and that their job became more stressful because of COVID-19 (53%). Moreover, 28% had considered quitting their job. Most respondents (78%) had received at least 1 dose of COVID-19 vaccine. Common reasons for vaccination were a desire to protect family and friends (84%) and a desire to stop the spread of COVID-19 (82%). Potential side effects and/or inadequate vaccine testing were cited as the most common concerns by unvaccinated HCP.
Conclusions:
A significant proportion of HCP reported increased stress and responsibilities at work due to COVID-19. The majority were vaccinated. Improving workplace policies related to mental health resources and sick leave, maintaining access to PPE, and ensuring clear communication of PPE requirements may improve workplace stress and burnout.
We investigate the late-time Richtmyer–Meshkov instability (RMI) growth of sinuous perturbations on an air/sulphur hexafluoride interface (Atwood number, $A \sim 0.67$) subjected to a Mach 1.2 planar shock wave at Los Alamos National Laboratory's vertical shock tube facility. Interface perturbations are established using a novel membraneless technique where cross-flowing air and SF$_6$ separated by an oscillating splitter plate create a perturbed density interface. The interface formed has multi-modal features and residual small perturbations, however, a dominant mode is still noticeable. The late-time perturbation growths scale with $ka_0$ initial conditions (where $k$ is the wavenumber and $a_0$ is the initial amplitude of the dominant mode) as measured at the pre-shock interface. Past nonlinear models based on potential-flow theory, heuristic/interpolation approaches, Padé approximants and numerical simulations are evaluated against present experimental results. Accounting for an explicit $ka_0$ dependence in Sadot et al.'s (Phys. Rev. Lett., vol. 80, issue 8, 1998, pp. 1654–1657) model, we propose an empirical rational function that captures the asymptotic behaviour of perturbation growth for a broad range of initial conditions ($0.30 \leq ka_0 \leq 0.86$). The onset of mixing transition and its initial condition dependence are investigated with respect to the minimum state criterion ($Re = 1.6 \times 10^5$) for unsteady flows by Zhou (Phys. Plasmas, vol. 14, 2007, 082701). Earlier mixing transitions for higher $ka_0$ initial conditions are noted from local and global Reynolds number estimates which are corroborated by the existence of an inertial sub-range and formation of mixing regions indicating the physical significance of the minimum state criterion in RMI flows. The transition is accompanied by the increasing teapot-like appearance of joint probability density functions of $p$–$q$ (invariants of the reduced velocity gradient tensor), establishing the technique as a useful tool for turbulence detection in two-dimensional diagnostics.
During cultural and social upheavals including manmade environmental factors like war and violence, drastic change takes place in people's expectations, “the meaning of life” and values. The purpose of this study was to examine the prevalence of psychiatric co morbidities in traumatic amputees in Kashmir (Indian Part).
Methods
Subjects were 100 consecutive patients with traumatic limb amputation. In addition to assessments of physical factors, psychiatric interviews were administered to examine mental disorders including PTSD and major depression.
Results
The prevalence rates of PTSD and major depression were 20% and 63% respectively. It was followed by impulse control disorder 19%, phantom limb phenomenon 14%, generalized anxiety disorder 10% and panic disorder 6%. Motor vehicle accident and blast injuries were cause for 53% and 11% of limb amputations respectively. Majority (45%) of them were males in age group of 15-30 years. 61% were illiterate from rural areas (81%).
Discussion
These findings suggest that psychiatric co morbidity is very common in amputees. Most of the patients are males of younger age group. Major depressive disorder is the most common psychiatric co morbidity followed by anxiety disorders in which PTSD is most prevalent, followed by impulse control disorder and phantom phenomenon respectively. Individuals suffering traumatic limb loss at any age are likely to suffer subsequent difficulties with their body image, but these relationships are more striking in the younger age groups who have experienced traumatic injuries.
We investigate the impact and penetration of a solid sphere passing through gelatine at various impact speeds up to $143.2~\text{m}~\text{s}^{-1}$. Tests were performed with several concentrations of gelatine. Impacts for low elastic Froude number $\mathit{Fr}_{e}$, a ratio between inertia and gelatine elasticity, resulted in rebound. Higher $\mathit{Fr}_{e}$ values resulted in penetration, forming cavities with prominent surface textures. The overall shape of the cavities resembles those observed in water-entry experiments, yet they appear in a different order with respect to increasing inertia: rebound, quasi-seal, deep-seal, shallow-seal and surface-seal. Remarkably, similar to the $We$–$Bo$ phase diagram in water-entry experiments, the elastic Froude number $\mathit{Fr}_{e}$ and elastic Grashof number $\mathit{Gr}_{e}$ (a ratio between gravity and gelatine elasticity) classify all five different phenomena into distinguishable regimes. We find that $\mathit{Fr}_{e}$ can be a good indicator to describe the cavity length $H$, particularly in the shallow-seal regime. Finally, the evolution of cavity shape, pinch-off depth, and lower cavity radius are investigated for different $\mathit{Fr}_{e}$ values.
Applying artificial intelligence to materials research requires abundant curated experimental data and the ability for algorithms to request new experiments. ESCALATE (Experiment Specification, Capture and Laboratory Automation Technology)—an ontological framework and open-source software package—solves this problem by providing an abstraction layer for human- and machine-readable experiment specification, comprehensive and extensible (meta-) data capture, and structured data reporting. ESCALATE simplifies the initial data collection process, and its reporting and experiment generation mechanisms simplify machine learning integration. An initial ESCALATE implementation for metal halide perovskite crystallization was used to perform 55 rounds of algorithmically-controlled experiment plans, capturing 4336 individual experiments.
It is well known that the water entry of a sphere causes cavity formation above a critical impact velocity as a function of the solid–liquid contact angle; Duez et al. (Nat. Phys., vol. 3 (3), 2007, pp. 180–183). Using a rough sphere with a contact angle of $120^{\circ }$, Aristoff & Bush (J. Fluid Mech., vol. 619, 2009, pp. 45–78) showed that there are four different cavity shapes dependent on the Bond and Weber numbers (i.e., quasistatic, shallow, deep and surface). We experimentally alter the Bond number, Weber number and contact angle of smooth spheres and find two key additions to the literature: (1) cavity shape also depends on the contact angle; (2) the absence of a splash crown at low Weber number results in cavity formation below the predicted critical velocity. In addition, we use alternate scales in defining the Bond, Weber and Froude numbers to predict the cavity shapes and scale pinch-off times for various impacting bodies (e.g., spheres, multidroplet streams and jets) on the same plots, merging the often separated studies of solid–liquid and liquid–liquid impact in the literature.
We report results from an experimental study on the formation of stable–streamlined and helical cavity wakes following the free-surface impact of Leidenfrost spheres. Similar to the observations of Mansoor et al. (J. Fluid Mech., vol. 743, 2014, pp. 295–326), we show that acoustic ripples form along the interface of elongated cavities entrained in the presence of wall effects as soon as the primary cavity pinch-off takes place. The crests of these ripples can act as favourable points for closure, producing multiple acoustic pinch-offs, which are found to occur in an acoustic pinch-off cascade. We show that these ripples pacify with time in the absence of physical contact between the sphere and the liquid, leading to extremely smooth cavity wake profiles. More importantly, the downward-facing jet at the apex of the cavity is continually suppressed due to a skin-friction drag effect at the colliding cavity-wall junction, which ultimately produces a stable–streamlined cavity wake. This streamlined configuration is found to experience drag coefficients an order of a magnitude lower than those acting on room-temperature spheres. A striking observation is the formation of helical cavities which occur for impact Reynolds numbers $Re_{0}\gtrsim 1.4\times 10^{5}$ and are characterized by multiple interfacial ridges, stemming from and rotating synchronously about an evident contact line around the sphere equator. The contact line is shown to result from the degeneration of Kelvin–Helmholtz billows into turbulence which are observed forming along the liquid–vapour interface around the bottom hemisphere of the sphere. Using sphere trajectory measurements, we show that this helical cavity wake configuration has 40 %–55 % smaller force coefficients than those obtained in the formation of stable cavity wakes.
We investigate the inception of cavitation and resulting structures when a sphere collides with a solid surface covered with a layer of non-Newtonian liquid having a kinematic viscosity of up to ${\it\nu}_{0}=20\,000\,000$ cSt. We show the existence of shear-stress-induced cavitation during sphere approach towards the base wall (i.e. the pressurization stage) in ultra-viscous films using a synchronized dual-view high-speed imaging system. For the experimental parameters employed, liquids having viscoelastic properties of $De\geqslant O(1)$ are shown to enable sphere rebound without any prior contact with the solid wall. Cavitation by depressurization (i.e. during rebound) in such non-contact cases is observed to onset after a noticeable delay from when the minimum gap distance is reached. Also, the cavities created originate from remnant bubbles, being the remains of the primary bubble entrapment formed by the lubrication pressure of the air during film entry. Cases where physical contact occurs (contact cases) in 10 000 cSt ${\leqslant}{\it\nu}_{0}\leqslant 1000\,000$ cSt films produce cavities attached to the base wall, which extend into an hourglass shape. In contrast, strikingly different structures occur in the most viscous liquids due to the disproportionality in radial expansion and longitudinal extension along the cavity length. Horizontal shear rates calculated using particle image velocimetry (PIV) measurements show the apparent fluid viscosity to vary substantially as the sphere approaches and rebounds away from the base wall. A theoretical model based on the lubrication assumption is solved for the squeeze flow in the regime identified for shear-induced cavity events, to investigate the criterion for cavity inception in further detail.
We present new observations from an experimental investigation of the classical problem of the crown splash and sealing phenomena observed during the impact of spheres onto quiescent liquid pools. In the experiments, a 6 m tall vacuum chamber was used to provide the required ambient conditions from atmospheric pressure down to $1/16\text{th}$ of an atmosphere, whilst high-speed videography was exploited to focus primarily on the above-surface crown formation and ensuing dynamics, paying particular attention to the moments just prior to the surface seal. In doing so, we have observed a buckling-type azimuthal instability of the crown. This instability is characterised by vertical striations along the crown, between which thin films form that are more susceptible to the air flow and thus are drawn into the closing cavity, where they atomize to form a fine spray within the cavity. To elucidate to the primary mechanisms and forces at play, we varied the sphere diameter, liquid properties and ambient pressure. Furthermore, a comparison between the entry of room-temperature spheres, where the contact line pins around the equator, and Leidenfrost spheres (i.e. an immersed superheated sphere encompassed by a vapour layer), where there is no contact line, indicates that the buckling instability appears in all crown sealing events, but is intensified by the presence of a pinned contact line.
This study describes the first large-scale serosurvey on West Nile virus (WNV) conducted in the equine population in Pakistan. Sera were collected from 449 equids from two provinces of Pakistan during 2012–2013. Equine serum samples were screened using a commercial ELISA kit detecting antibodies against WNV and related flaviviruses. ELISA-positive samples were further investigated using virus-specific microneutralization tests (MNTs) to identify infections with Japanese encephalitis virus (JEV), WNV and tick-borne encephalitis virus (TBEV). Anti-WNV antibodies were detected in 292 samples by ELISA (seroprevalence 65·0%) and WNV infections were confirmed in 249 animals by MNT. However, there was no animal found infected by JEV or TBEV. The detection of WNV-seropositive equines in Pakistan strongly suggests a widespread circulation of WNV in Pakistan.
The common green lacewing Chrysoperla carnea is a key biological control agent employed in integrated pest management (IPM) programs for managing various insect pests. Spinosad is used for the management of pests in ornamental plants, fruit trees, vegetable and field crops all over the world, including Pakistan. A field-collected population of C. carnea was selected with spinosad and fitness costs and realized heritability were investigated. After selection for five generations, C. carnea developed 12.65- and 73.37-fold resistance to spinosad compared to the field and UNSEL populations. The resistant population had a relative fitness of 1.47, with substantially higher emergence rate of healthy adults, fecundity and hatchability and shorter larval duration, pupal duration, and development time as compared to a susceptible laboratory population. Mean relative growth rate of larvae, intrinsic rate of natural population increase and biotic potential was higher for the spinosad-selected population compared to the susceptible laboratory population. Chrysoperla species are known to show resistance to insecticides which makes the predator compatible with most IPM systems. The realized heritability (h2) value of spinosad resistance was 0.37 in spinosad-selected population of C. carnea.
We report results from an experimental study of cavity formation during the impact of superhydrophobic spheres onto water. Using a simple splash-guard mechanism, we block the spray emerging during initial contact from closing thus eliminating the phenomenon known as ‘surface seal’, which typically occurs at Froude numbers $\mathit{Fr}= V_{0}^{2}/(gR_{0}) = O(100)$. As such, we are able to observe the evolution of a smooth cavity in a more extended parameter space than has been achieved in previous studies. Furthermore, by systematically varying the tank size and sphere diameter, we examine the influence of increasing wall effects on these guarded impact cavities and note the formation of surface undulations with wavelength $\lambda =O(10)~ \mathrm{cm}$ and acoustic waves $\lambda _{a}=O(D_{0})$ along the cavity interface, which produce multiple pinch-off points. Acoustic waves are initiated by pressure perturbations, which themselves are generated by the primary cavity pinch-off. Using high-speed particle image velocimetry (PIV) techniques we study the bulk fluid flow for the most constrained geometry and show the larger undulations ($\lambda =O (10~ \mathrm{cm}$)) have a fixed nature with respect to the lab frame. We show that previously deduced scalings for the normalized (primary) pinch-off location (ratio of pinch-off depth to sphere depth at pinch-off time), $H_{p}/H = 1/2$, and pinch-off time, $\tau \propto (R_{0}/g)^{1/2}$, do not hold for these extended cavities in the presence of strong wall effects (sphere-to-tank diameter ratio), $\epsilon = D_{0}/D_{tank} \gtrsim 1/16$. Instead, we find multiple distinct regimes for values of $H_{p}/H$ as the observed undulations are induced above the first pinch-off point as the impact speed increases. We also report observations of ‘kinked’ pinch-off points and the suppression of downward facing jets in the presence of wall effects. Surprisingly, upward facing jets emanating from first cavity pinch-off points evolve into a ‘flat’ structure at high impact speeds, both in the presence and absence of wall effects.
Dengue has become the fastest-growing mosquito-borne disease in Sri Lanka and the control of the vectors, Aedes aegypti Linnaeus and Ae. albopictus Skuse, is the most effective way of controlling the disease. A detailed study on vector prevalence has not been recorded from Sri Lanka. Therefore, the present study was undertaken to study the prevalence of both vectors in four semi-urban study sites in two of the most affected districts, namely Kandy (wet zone) and Kurunegala (intermediate zone), by conducting egg surveys (using ovitraps) and larval surveys from June 2007 to May 2008. A total of 82,524 eggs and 2658 larvae of Ae. aegypti and Ae. albopictus were collected. A total of 3699 potential breeding habitats were examined. Ovitrap and larval indices (house, container and Breteau) showed that all four areas are at epidemic risk, especially due to a high abundance of Ae. albopictus. The highest numbers for both the species were from the Kandy sites where dense vegetation, high rainfall and low temperature prevailed. The results showed a high mortality rate during the egg-to-larva transition, suggesting that conducting an egg survey alone would overestimate the vector abundance and the disease risk. For Ae. albopictus, the monthly mean number of eggs showed positive relationships with relative humidity in both districts and with rainfall in the Kandy District. The number of dengue cases in the area had no positive relationships with the abundance of eggs or larval density indices. Discarded receptacles were the most preferred breeding habitat for these dengue vectors. Since the attractiveness (inferred by the calculated risk factors) of most of the breeding habitats was very high, elimination of these breeding sites is essential for the success of dengue control programmes.
This is a copy of the slides presented at the meeting but not formally written up for the volume.
Abstract
Nanotechnology is expected to have a revolutionary impact on medical diagnosis and therapy. In cancer therapy, targeting and localized delivery are the key challenges. To wage an effective war against cancer, we have to have the ability to selectively attack the cancer cells, while saving the normal tissue from excessive burdens of drug toxicity. In this presentation, I will discuss the different nanotechnology platforms that we have developed for targeted drug and gene delivery to tumor mass. Special emphasis will be placed on nano-platforms that offer opportunities for multi-functionalization to allow for simultaneous strategic delivery of multiple therapeutic agents or combining imaging and therapeutic modalities. Results from our laboratory at Northeastern University show that polymer- and lipid-based nanosystems can provide versatile platforms for delivery of multiple therapeutic agents, specifically to enhance therapeutic effect and overcome drug resistance in cancer. In addition, polymeric nanoparticles are used for tumor-targeted anti-angiogenic gene therapy. Nanoemulsions, made from oils rich in polyunsaturated fatty acid, offer an opportunity to facilitate transport across biological barriers for targeted delivery of drugs and imaging agents. Lastly, I will discuss our work on gold and iron oxide-gold nanostructures that are functionalized for targeted imaging and drug delivery applications.
The disease risk indicator plasma total homocysteine (tHcy) is influenced by genetic and environmental factors, including folate and vitamin B12 status. Little is known about the determinants of tHcy in rural West Africa. We explored the hypothesis that tHcy in rural Gambian adults might vary between the sexes and physiological groups, an/r with folate and vitamin B12 status. Comparisons were made with a British national survey. Non-pregnant Gambian women (n 158) had tHcy concentrations (geometric mean 9·0μmo/) similar to those of non-pregnant UK women (n 449; 9·4μmo/), whereas pregnant Gambian women (n 12) had significantly lower values (6·2μmo/). Gambian men (n 22) had significantly higher values (14·7μmo/) than British men (n 354; 10·8μmo/). Gambian lactating women and British men and women exhibited significant inverse relationships between loge(tHcy) and folate status; however, only the British subjects exhibited significant inverse relationships between loge(tHcy) and vitamin B12 status. In the British sample, and in Gambian lactating women, folate and vitamin B12 status variations together accounted for 20–25% of the variation in loge(tHcy). Within the UK, black-skinned adults had folate and tHcy levels similar to those of their white-skinned counterparts, but significantly higher vitamin B12 values. We conclude that, whereas folate and vitamin B12 status are similar between British and rural Gambian populations, tHcy is higher in Gambian men and lower in pregnant Gambian women, and that serum vitamin B12 values appear to be higher in black-skinned than white-skinned British subjects. Possible reasons are discussed.