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Unified strength model for FRP confined heat-damaged circular and square concrete columns
Full text linkAlthough a variety of analytically modeling approaches have been developed to simulate axial response of Fiber-Reinforced Polymer (FRP) confined concrete columns, little effort has been dedicated to the development of simple but robust predictive models for heat-damaged concrete columns with FRP confinement. This study aims to present a new unified strength model for predicting the peak compressive strength of FRP confined heat-damaged concrete with circular/square cross-section columns, applicable to both ambient and elevated temperature conditions. In order to achieve the highest level of reliability and predictive performance, a large database of experimental results available in the literature was assembled. In this model, the influences of column size, sectional non-circularity, and pre-existing thermal-induced damage in terms of confinement-induced improvements were considered in the model establishment based on regression analysis. The reliability of the developed model is demonstrated by simulating experimental counterparts and also comparing it to the predictive performance of existing strength models
The Radial Variation of the Solar Wind Turbulence Spectra near the Kinetic Break Scale from Parker Solar Probe Measurements
Full text linkIn this study we examine the radial dependence of the inertial and dissipation range indices, as well as the spectral break separating the inertial and dissipation range in power density spectra of interplanetary magnetic field fluctuations using Parker Solar Probe data from the fifth solar encounter between ∼0.1 and ∼0.7 au. The derived break wavenumber compares reasonably well with previous estimates at larger radial distances and is consistent with gyro-resonant damping of Alfvénic fluctuations by thermal protons. We find that the inertial scale power-law index varies between approximately −1.65 and −1.45. This is consistent with either the Kolmogorov (−5/3) or Iroshnikov–Kraichnan (−3/2) values, and has a very weak radial dependence with a possible hint that the spectrum becomes steeper closer to the Sun. The dissipation range power-law index, however, has a clear dependence on radial distance (and turbulence age), decreasing from −3 near 0.7 au (4 days) to −4 [±0.3] at 0.1 au (0.75 days) closer to the Sun
Influence of curvature distribution smoothing on the reduction of aerofoil self-noise
Full text linkPurpose – The paper aims to investigate the influence of smooth curvature distributions on the self-noise of a low Reynolds number aerofoil and to unveil the flow mechanisms in the phenomenon.
Design/methodology/approach – The paper performed Large Eddy Simulation (LES) approach to investigate the unsteady aerodynamic performance of both the original aerofoil E387 and the redesigned aerofoil A7 in a time-dependent
study of boundary layer characteristics at Reynolds number 100,000 and Angle of Attack 4-degree. The aerofoil A7 is redesigned from E387 by removing the irregularities in the surface curvature distributions and keeping a nearly identical
geometry. Flow vorticity magnitude of both aerofoils, along with the spectra of the vertical fluctuating velocity component and noise level, are analysed to demonstrate the bubble flapping process near the trailing edge and the vortex shedding phenomenon.
Findings – The paper provides quantitative insights about how the flapping process of the laminar separation bubble within the boundary layer near the trailing edge affects the aerofoil self-noise. It is found that the aerofoil A7 with smooth curvature distributions presents a 10% smaller laminar separation bubble compared to the aerofoil E387 at Reynolds number 100,000 and Angle of Attack 4-degree. The LES results also suggests that curvature distribution smoothing leads to a 6.5% reduction in overall broadband noise level.
Originality/value – This paper fulfils an identified need to reveal the unknown flow structure and the boundary layer characteristics that resulted in the self-noise reduction phenomenon yielded by curvature distribution smoothing
Communicating knowledge and embodied experiences of personal menstrual cup use through YouTube
Full text linkBackground: Despite being a normal part of life for many, menstruation is often stigmatized resulting in reduced knowledge of reusable products such as menstrual cups. YouTube videos can raise awareness of menstrual cups and challenge stigma, but little is known about the content creators or what content is communicated in the videos.
Aim: Firstly, to examine vlogger characteristics and the content of videos sharing personal experiences of cup use. Secondly, to evaluate the potential of these videos as a way of communicating about menstrual health.
Methods: A content analysis of the 100 most popular menstrual cup videos on YouTube followed by a qualitative thematic analysis of 50 videos containing personal experiences.Results:The content of the videos was captured in four themes: embodied knowledge; technology enabled intimacies; persuasive narratives and a collective sense of community.
Discussion: Vloggers communicated knowledge and embodied experiences of personal cup use. This represents a step towards destigmatizing menstruation and menstruants’ bodies, but issues around the complexities of vloggers’ motivations and the situatedness of vloggers remain.
Conclusions: Given the paucity of information on menstruation and reusable menstrual products, YouTube videos provide a potentially valuable resource for health communication and education especially for younger menstruants
Social Work and Domestic Violence in Croatia Through a Gendered Lens: Between Power and Precarity: Socijalni rad i obiteljsko nasilje u Hrvatskoj kroz orođeni pogled: između moći i prekarijata
Full text linkThis article examines the gender-blind perception of the social work profession in Croatia and its relation to domestic violence cases. In the past few years, the media and the public have routinely expressed outrage at social workers for not preventing severe cases of violence against women and children. The shift from state socialism to capitalism in Croatian society has considerably affected the profession of social work and facilitated the defunding and understaffing of the welfare sector. I argue that a more nuanced, gendered approach is needed in demanding prevention work from social work centres (SWC). Most studies on the causes of burnout in social workers have ignored the feminisation of the profession and the gendered implication of their precarious professional position and responsibility to protect and help the most vulnerable members of society. The perceptions of social work by other experts working with cases of domestic violence and social workers themselves are important to comprehend a bigger picture of professional judgment and attributions of blame. In-depth interviews were conducted with experts working with domestic violence, including the police, judges, prosecutors, social workers, feminist NGO coordinators, and women’s shelter workers. The feminisation of social work and systemic undervaluing of care work contribute to the easy targeting of social workers while leaving the patriarchal institutionalisation unexplored. For this reason, I conclude that social workers would benefit from class and gender solidary with their clients to fight patriarchal biases
A spatio-temporal framework for modelling wastewater concentration during the COVID-19 pandemic
Full text linkThe potential utility of wastewater-based epidemiology as an early warning tool has been explored widely across the globe during the current COVID-19 pandemic. Methods to detect the presence of SARS-CoV-2 RNA in wastewater were developed early in the pandemic, and extensive work has been conducted to evaluate the relationship between viral concentration and COVID-19 case numbers at the catchment areas of sewage treatment works (STWs) over time. However, no attempt has been made to develop a model that predicts wastewater concentration at fine spatio-temporal resolutions covering an entire country, a necessary step towards using wastewater monitoring for the early detection of local outbreaks.
We consider weekly averages of flow-normalised viral concentration, reported as the number of SARS-CoV-2N1 gene copies per litre (gc/L) of wastewater available at 303 STWs over the period between 1 June 2021 and 30 March 2022. We specify a spatially continuous statistical model that quantifies the relationship between weekly viral concentration and a collection of covariates covering socio-demographics, land cover and virus associated genomic characteristics at STW catchment areas while accounting for spatial and temporal correlation.
We evaluate the model’s predictive performance at the catchment level through 10-fold cross-validation. We predict the weekly viral concentration at the population-weighted centroid of the 32,844 lower super output areas (LSOAs) in England, then aggregate these LSOA predictions to the Lower Tier Local Authority level (LTLA), a geography that is more relevant to public health policy-making. We also use the model outputs to quantify the probability of local changes of direction (increases or decreases) in viral concentration over short periods (e.g. two consecutive weeks).
The proposed statistical framework can predict SARS-CoV-2 viral concentration in wastewater at high spatio-temporal resolution across England. Additionally, the probabilistic quantification of local changes can be used as an early warning tool for public health surveillance
Immersive and Non-Immersive Virtual Reality for Pain and Anxiety Management in Pediatric Patients with Hematological or Solid Cancer: A Systematic Review
Full text linkInvasive and painful procedures, which often induce feelings of anxiety, are necessary components of pediatric cancer treatment, and adequate pain and anxiety management during these treatments is of pivotal importance. In this context, it is widely recognized that a holistic approach, including pharmacological and non-pharmacological modalities, such as distraction techniques, should be the standard of care. Recent evidence suggested the use of virtual reality (VR) as an effective non-pharmacological intervention in pediatrics. Therefore, this systematic review aims to analyze previously published studies on the effectiveness of VR for the management of pain and/or anxiety in children and adolescents with hematological or solid cancer. Medline, SCOPUS, Web of Science, ProQuest, CINAHL, and The Cochrane Central Register of Controlled Trials were used to search for relevant studies in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist. Randomized controlled trial, crossover trial, cluster randomized trial, and quasi-experimental studies were included. Thirteen studies, published between 1999 and 2022, that fulfilled the inclusion criteria were included. Regarding the primary outcomes measured, pain was considered in five studies, anxiety in three studies, and the remaining five studies analyzed the effectiveness of VR for both pain and anxiety reduction. Our findings suggested a beneficial effect of VR during painful vascular access procedures. Limited data are available on the reduction of anxiety in children with cancer
Twice-milled magnetic biochar: A recyclable material for efficient removal of methylene blue from wastewater
Full text linkAlthough magnetic modification has potential for preparing recyclable biochar, the traditional preparation methods of loading magnetic materials on biochar will probably lead to pore blockage and consequently remarkable adsorption recession. Herein, a preparation method was developed in which ball milled biochar was loaded with ultrafine magnetite and then milled for a second time, thus generating a magnetic, recyclable biochar with minimal pore blockage. The deposits of magnetite did not significantly wrap the biochar, although a decreased sorption performance was still detectable. Benefitting from the extra milling step, surface functional groups and specific surface areas of the adsorbents were largely restored, thus leading to a 93.8 % recovery adsorption of 84.6 ± 2.5 mg/L on methylene blue. Meanwhile, the recyclability of the material was not affected. The adsorption was driven by multiple interactions. These twice-milled magnetic biochar is quite outstanding for sustainable removal of aqueous contaminants with its recyclability and high sorption efficiency
Cooling performance of an active-passive hybrid composite phase change material (HcPCM) finned heat sink: Constant operating mode
Full text linkThe present study explores a hybrid thermal management technology based on air cooling and hybrid composite phase change material (HcPCM) filled finned heat sink for cooling performance of lower to medium heat flux dissipating electronic devices. Two-dimensional numerical simulations are conducted to study the conjugate heat transfer effects of three types of finned heat sink: air-cooled finned heat sink, HcPCM-cooled finned heat sink, and hybrid (air-HcPCM) cooled finned heat sink. A heat sink with a constant volume faction of plate-fins is designed in all cases and simultaneous effects of hybrid nanoparticles and air are investigated to keep the heat sink temperature at safe operating conditions between 40–60 ∘C. The effect of air is incorporated into the heat sink by applying the convective heat transfer coefficient of ℎc = 10–100 W/m2.K which tends to create the natural convection and forced convection heat transfer characteristics. The heat flux is varied from 25–40 kW/m2 in the current study. The hybrid nanoparticles of carbon additives (GO and MWCNTs) are dispersed into the RT-35HC, used as a PCM, with a volume fraction of 0% to 6%. Transient simulations are carried out using COMSOL Multiphysics to solve the governing equations for PCM based conjugate heat transfer model. The results showed that forced convection heat transfer improved the cooling performance of the hybrid heat sink compared to natural convection heat transfer. The addition of nanoparticles further enhanced thermal enhancement and uniform melting distribution of PCM inside the finned heat sink. The ℎcbetween 30 to 50 W/m2.K shows optimized values for forced convection heat transfer operating conditions. The volume fraction of 2% of GO+MWCNTs nanoparticles in recommended or optimum concentration for uniform melting of PCM inside the finned heat sink
Duty free: Turning the criminological spotlight on special economic zones
Full text linkSpatially designated economic zones render countries vulnerable to crime and harm, while simultaneously diffusing and escalating these problems across the globe. Yet, criminological analysis of special economic zones (SEZs) and similar areas remains limited. This article analyses the kinds of criminality and harm attached to such fiscal and commodity enclaves. Our analysis begins with the history of SEZs. We then offer a typology of related harms: 1. illicit trade; 2. the protection of wealth holdings; and 3. environmental harm. Our closing theoretical discussion suggests how the expansion of economic strategies involving SEZs is generative of new and complex forms of harm and crime embedded in the spatial architecture of the global economy