448 research outputs found
Image-based abuse: Gender differences in bystander experiences and responses
Image-based abuse (IBA) refers to the non-consensual taking, sharing or threat to share nude or sexual images. Research suggests people who witness IBA behaviours can reduce the extent and impacts of its harm by taking action to intervene. However, there is limited research available on the attitudes, experiences and role of bystanders in the prevention of IBA. This paper presents findings from a national study examining bystanders’ experiences of, and responses to, witnessing IBA. Informed by a survey of 245 Australian adults in four jurisdictions, this paper shows that while witnessing IBA is common, few respondents reported taking action to intervene, and there are gender differences in bystander readiness to intervene. The findings have important implications for the development of bystander intervention and education programs
Quantification of rubidium as a trace element in beef using laser induced breakdown spectroscopy
This study evaluates the potential of laser induced breakdown spectroscopy (LIBS) coupled with chemometrics to develop a quantification model for rubidium (Rb) in minced beef. A LIBSCAN 150 system was used to collect LIBS spectra of minced beef samples. Beef liver was used to spike the Rb levels in minced beef. All samples were dried, powdered and pelleted using a hydraulic press. Measurements were conducted by scanning 100 different locations with an automated XYZ sample chamber. Partial least squares regression (PLSR) was used to develop the calibration model, yielding a calibration coefficient of determination (Rc2) of 0.99 and a root mean square error of calibration (RMSEC) of 0.05ppm. The model also showed good results with leave-one-out cross validation, yielding a cross-validation coefficient of determination (Rcv2) of 0.90 and a root mean square error of cross-validation (RMSECV) of 0.22ppm. The current study shows the potential of LIBS as a rapid analysis tool for the meat processing industry
Laboratory-scale interaction between CO2-rich brine and limestone and sandstone under supercritical CO2 conditions.
Victim-blaming and image-based sexual abuse
Image-based sexual abuse (IBSA) is a growing, global problem. This article reports on a mixed-methods, multi-jurisdictional study of IBSA across the United Kingdom, Australia and Aotearoa/New Zealand. Attitudes of blame and minimisation of harms among a sample of the general population (n=6,109) were analysed using two multiple regression analyses that assessed the ability of three demographic and three experiential characteristics to predict attitudes. Interviews were also conducted with 43 stakeholders and analysed thematically. Survey respondents who attributed more blame and minimised harms to a greater extent tended to be men, heterosexual, and had experienced or perpetrated more IBSA behaviours. Those who reported greater engagement in sexual self-image behaviours were also more likely to minimise harms. Interview participants suggested attitudes of blame and minimisation may be linked to broader problematic attitudes around sexual violence and sexual double standards, with women more likely to experience blame for IBSA. Our findings are of international relevance and highlight the need for multifaceted policies, education campaigns and training that challenge these attitudes
Preventing image-based abuse in Australia: The role of bystanders
This report examines image-based abuse and bystander intervention in Australia. Image-based abuse involves three main behaviours—non-consensually taking/creating nude or sexual images, non-consensually sharing/distributing nude or sexual images, and threatening to share/distribute nude or sexual images. In this report, we present data from an online survey of 245 Australian residents (aged 18–71 years), 35 face-to-face focus groups with 219 participants and a review of available resources on bystander intervention and image-based abuse. Ultimately, we found that many people do not intervene when witnessing image-based abuse. While 64.1 percent of respondents had witnessed image-based abuse, only 45.6 percent reported that they said or did something. We also discuss a range of barriers to and facilitators of intervention, such as the social and physical safety risks of intervention, potential impacts on interpersonal relationships, gender, the potential for escalation, and whether participants perceived they would receive support from others. The report also shows that participants have limited knowledge of existing image-based abuse resources and supports. We argue that improved education and awareness of image-based abuse is needed to actively discourage it and highlight its harms and consequences, alongside education on how bystanders can safely and effectively intervene and/or support victims when witnessing image-based abuse
A label-free microfluidic assay to quantitatively study antibiotic diffusion through lipid membranes
PublishedJournal ArticleResearch Support, Non-U.S. Gov'tWith the rise in antibiotic resistance amongst pathogenic bacteria, the study of antibiotic activity and transport across cell membranes is gaining widespread importance. We present a novel, label-free microfluidic assay that quantifies the permeability coefficient of a broad spectrum fluoroquinolone antibiotic, norfloxacin, across lipid membranes using the UV autofluorescence of the drug. We use giant lipid vesicles as highly controlled model systems to study the diffusion through lipid membranes. Our technique directly determines the permeability coefficient without requiring the measurement of the partition coefficient of the antibiotic.This work was supported by a European Research Council
(ERC) grant (261101 PassMembrane) to UFK. JC
acknowledges support from an Internal Graduate Studentship,
Trinity College, Cambridge. CC is supported by the ERC. SP
acknowledges the support of the Leverhulme Trust and the
Newton Trust through an Early Career Fellowship. AJ is
supported by the Mexican National Council of Science and
Technology. We thank Thomas Muller for help with the
lithography and Tuomas Knowles for the use of his lithography
facilitie
Feasibility of laser-induced breakdown spectroscopy (LIBS) as an at-line validation tool for calcium determination in infant formula
In this study, a 150 mJ laser-induced breakdown spectroscopy (LIBS) system was assessed to determine calcium content in infant formula (IF) samples. LIBS is a promising emission spectroscopic technique for elemental analysis, which offers advantages over conventional methods such as real-time analyses, little to no sample preparation and ease of use. The aim of this work was to evaluate the feasibility of LIBS as an at-line tool for IF manufacturing. To this end, IF mixtures with varying content of calcium were prepared over a range (approx. 1.5–7 mg/g of calcium) selected to be in conformity with the guidelines provided by the Codex Alimentarius Commission. Atomic Absorption Spectroscopy (AAS) was used as the reference method for mineral content determination in IF. Partial least squares regression (PLSR) was applied to the LIBS spectral data to develop a calibration model for calcium content quantification. A validation approach was then carried out to investigate the robustness of the model, which showed a good fit with values of R2cv of 0.90 for cross-validation and a R2p 0.85 for external validation. Low values for root mean square errors of cross-validation (RMSECV) and prediction (RMSEP) of 0.62 mg/g and 0.68 mg/g were obtained. Furthermore, this study also illustrated the possibility of LIBS to provide mineral prediction maps as a useful tool for testing sample homogeneity
Laser-induced breakdown spectroscopy (LIBS) for food analysis: A review
Background Laser-induced breakdown spectroscopy (LIBS) is an atomic emission spectroscopic technique which uses a focused pulsed laser beam to generate plasma from the material. The plasma contains atoms, ions and free electrons which emit electromagnetic radiation as the plasma cools down. The emitted light is resolved by a spectrometer to form a spectrum. Recently, LIBS has become an emerging analytical technique for characterisation and identification of materials; its multi-elemental analysis, fast response, remote sensing, little to no sample preparation, low running cost and ease of use make LIBS a promising technique for the food sector.
Scope and approach The present article reviews the feasibility of LIBS for food analysis. It presents recent progress and applications of LIBS as an efficient and reagent-free, at-line tool capable of replacing traditional time-consuming analytical methods for assessing the quality and composition of food products. An overview of LIBS fundamentals, instrumentation and statistical data analysis is also provided.
Key findings and conclusions Although LIBS technology shows many advantages, challenges remain in terms of sample preparation, matrix effects, spectral pre-processing, model calibration and instrument development
Laser-induced breakdown spectroscopy (LIBS) for rapid analysis of ash, potassium and magnesium in gluten free flours
Gluten free (GF) diets are prone to mineral deficiency, thus effective monitoring of the elemental composition of GF products is important to ensure a balanced micronutrient diet. The objective of this study was to test the potential of laser-induced breakdown spectroscopy (LIBS) analysis combined with chemometrics for at-line monitoring of ash, potassium and magnesium content of GF flours: tapioca, potato, maize, buckwheat, brown rice and a GF flour mixture. Concentrations of ash, potassium and magnesium were determined with reference methods and LIBS. PCA analysis was performed and presented the potential for discrimination of the six GF flours. For the quantification analysis PLSR models were developed; R2cal were 0.99 for magnesium and potassium and 0.97 for ash. The study revealed that LIBS combined with chemometrics is a convenient method to quantify concentrations of ash, potassium and magnesium and present the potential to classify different types of flours
Quantification of trace metals in infant formula premixes using laser-induced breakdown spectroscopy
Infant formula is a human milk substitute generally based upon fortified cow milk components. In order to mimic the composition of breast milk, trace elements such as copper, iron and zinc are usually added in a single operation using a premix. The correct addition of premixes must be verified to ensure that the target levels in infant formulae are achieved. In this study, a laser-induced breakdown spectroscopy (LIBS) system was assessed as a fast validation tool for trace element premixes. LIBS is a promising emission spectroscopic technique for elemental analysis, which offers real-time analyses, little to no sample preparation and ease of use. LIBS was employed for copper and iron determinations of premix samples ranging approximately from 0 to 120mg/kg Cu/1640mg/kg Fe. LIBS spectra are affected by several parameters, hindering subsequent quantitative analyses. This work aimed at testing three matrix-matched calibration approaches (simple-linear regression, multi-linear regression and partial least squares regression (PLS)) as means for precision and accuracy enhancement of LIBS quantitative analysis. All calibration models were first developed using a training set and then validated with an independent test set. PLS yielded the best results. For instance, the PLS model for copper provided a coefficient of determination (R2) of 0.995 and a root mean square error of prediction (RMSEP) of 14mg/kg. Furthermore, LIBS was employed to penetrate through the samples by repetitively measuring the same spot. Consequently, LIBS spectra can be obtained as a function of sample layers. This information was used to explore whether measuring deeper into the sample could reduce possible surface-contaminant effects and provide better quantifications
- …