Modification and re-validation of the ethyl acetate-based multi-residue method for pesticides in produce

The ethyl acetate-based multi-residue method for determination of pesticide residues in produce has been modified for gas chromatographic (GC) analysis by implementation of dispersive solid-phase extraction (using primary–secondary amine and graphitized carbon black) and large-volume (20 μL) injection. The same extract, before clean-up and after a change of solvent, was also analyzed by liquid chromatography with tandem mass spectrometry (LC–MS–MS). All aspects related to sample preparation were re-assessed with regard to ease and speed of the analysis. The principle of the extraction procedure (solvent, salt) was not changed, to avoid the possibility invalidating data acquired over past decades. The modifications were made with techniques currently commonly applied in routine laboratories, GC–MS and LC–MS–MS, in mind. The modified method enables processing (from homogenization until final extracts for both GC and LC) of 30 samples per eight hours per person. Limits of quantification (LOQs) of 0.01 mg kg−1 were achieved with both GC–MS (full-scan acquisition, 10 mg matrix equivalent injected) and LC–MS–MS (2 mg injected) for most of the pesticides. Validation data for 341 pesticides and degradation products are presented. A compilation of analytical quality-control data for pesticides routinely analyzed by GC–MS (135 compounds) and LC–MS–MS (136 compounds) in over 100 different matrices, obtained over a period of 15 months, are also presented and discussed. At the 0.05 mg kg−1 level acceptable recoveries were obtained for 93% (GC–MS) and 92% (LC–MS–MS) of pesticide–matrix combinations

Stroke in women — from evidence to inequalities

Stroke is the second largest cause of disability-adjusted life-years lost worldwide. The prevalence of stroke in women is predicted to rise rapidly, owing to the increasing average age of the global female population. Vascular risk factors differ between women and men in terms of prevalence, and evidence increasingly supports the clinical importance of sex differences in stroke. The influence of some risk factors for stroke — including diabetes mellitus and atrial fibrillation — are stronger in women, and hypertensive disorders of pregnancy also affect the risk of stroke decades after pregnancy. However, in an era of evidence-based medicine, women are notably under-represented in clinical trials — despite governmental actions highlighting the need to include both men and women in clinical trials — resulting in a reduced generalizability of study results to women. The aim of this Review is to highlight new insights into specificities of stroke in women, to plan future research priorities, and to influence public health policies to decrease the worldwide burden of stroke in women

An ethnography of the choreography of pressure ulcer care practices in the NHS

The National Health Service (NHS) has been under pressure for years, with this rising further during the Covid-19 pandemic. In 2022-2023 nurses protested against the pressures they were experiencing and how this endangered patient safety in the largest nursing strikes in NHS history. In my study I focus on one particular aspect of patient safety; pressure ulcers. Pressure ulcers are injuries caused by continuous pressure on skin. In an ethnography of an NHS hospital and the medical device industry, I trace how the pressure on patients’ skin is connected to the pressure on the NHS. I find that wherever pressure builds up there are attempts to move it to other sites, people, things, and times. I show different ways that mess can result from this dynamic and different attempts to control it. The first paper demonstrates how nurses try to clean up messy ambiguities in the policy shift away from a ‘culture of blame’ to a ‘culture of learning’ in the NHS by advocating for different responsibilities, values, and interests in different contexts. The second paper unpacks how a multidisciplinary team investigating serious pressure ulcers in the hospital uses retrospective speculation and anticipation to control uncertainty in prevention. The third paper counters the technological solutionist promise that technologies relieve pressure on skin and staff by showing how pressure is not removed but moved and the politics of this redistribution. Drawing these three papers together, I conceptualise pressure ulcer care in the NHS as a ‘choreography’ to emphasise interdependencies between a variety of human and other-than-human actors, their routines and adaptations to specific situations, and the constant work that goes into organising and planning these practices. I reflect on the limitations of the pressure metaphor that links pressure ulcer prevention with contemporary debates about the state of the NHS

Preliminary evidence for green, brown and black worlds in tropical western Africa during the Middle and Late Pleistocene

Modern ecological studies indicate that the degree of openness in African vegetation cover is determined, in part, by the presence of herbivores and fire as consumers of vegetation. Where herbivores are the dominant consumer of vegetation the resultant open state is described as a ‘brown’world. Where fire is the dominant consumer of vegetation the resultant open state is described as a ‘black’ world. While if neither consumer is dominant then a more closed canopy states arises that is described as a ‘green’world. Here we use palaeoecological data obtained from Lake Bosumtwi (Ghana) to characterize green, brown, and black worlds during two short sections of around 1000 years each, deposited around 200,000 and 100,000 years ago(Middle and Late Pleistocene).We characterize the vegetation cover using pollen and phytoliths, herbivory using Sporormiella and fire using micro-charcoal. We find that during c. 1000 years of the Middle Pleistocene fire was the major consumer of vegetation, while during c. 1000 years in the Late Pleistocene herbivores were relatively more important consumers of vegetation. We therefore suggest that the Middle Pleistocene section represents a black world, while in the Late Pleistocene section we capture a combination of green, brown and black worlds. The duration of these states seems to range from centuries to millennia and transitions are observed to occur in both an abrupt and a stepwise fashion. These preliminary data demonstrate how palaeoecological information can be used to gain insights into past landscape scale processes over thousands of years. Further work is required to test the robustness of these findings and to provide a higher temporal resolution to aid the link with modern ecological studies