213476 research outputs found
Sort by
Interconnected Health-Environmental Challenges: The Implosion of the Modernist Evidence Regime and the Need of Pluralist Evidence Practices
No full textIncreased pollution, obesity rates, or the COVID-19 pandemic are only a few examples of the numerous intertwined health-environmental challenges humanity is facing. The severity of these challenges strongly suggests that research in these fields is failing to generate evidence to support decisions and actions that can help address, mitigate or adapt to them. In this article, we look into some of the underlying assumptions underpinning mainstream research in the health and in the environmental sciences; specifically, we focus on the separation between knowledge and action, mechanistic worldviews, and value-neutrality of research. We show that these assumptions underpin what we call a modernist evidence regime that is embedded in certain socio-cultural contexts. When these assumptions are at work in empirical research, interconnected health-environmental challenges cannot be appropriately addressed. We suggest, instead, that to do so we need to move towards a radically pluralist evidence regime. Such a regime sees knowledge and action as inextricably entangled, is based on a complexity-based understanding of the world, embraces the non-neutrality of research, and makes space for multiple methodological approaches
Contrasting behaviour of the marine- and land-based portions of the Lambert Glacier system in Prydz Bay, East Antarctica during the late Quaternary
No full textA better understanding of the past dynamical behaviour of the Antarctic Ice Sheet (AIS) is important for improving future sea-level projections. Previous studies mainly focused on the marine-based portions (MBP) of the AIS, whereas the response of the land-based portions (LBP) to climate change remains less well constrained. In this study, we reconstruct the behaviour of both the LBP and MBP of the Lambert Glacier-Amery Ice Shelf system (LGAISS) over the past 520 kyr using new records of elemental geochemistry from a sediment core retrieved offshore of Prydz Bay, East Antarctica. Our data reveal that the sediments were locally derived from Prydz Bay. The immobile elements in the sediments were sensitive to changes in bedrock sources that were mostly situated above sea level and thus serve as a tracer for the behaviour of the LBP of the LGAISS. In contrast, the mobile elements were related to the recycling of ancient chemically-weathered sediments on the continental shelf and can be used to investigate the behaviour of the MBP of the LGAISS. The MBP of the LGAISS was sensitive to a range of forcing mechanisms, including global sea-level change, oceanic processes, and local summer insolation, while the LBP may have mostly responded to eccentricity minima during glacial conditions. Our new data demonstrate that the coastal LBP of the LGAISS behaved differently from the MBP on orbital timescales, which should be considered in simulations to improve our understanding of AIS dynamics
Examining the Signal-Detection Account of Visual Working Memory
No full textThe study of visual working memory has long centered on debates between Signal Detection Theory (SDT) and discrete-slots models. A notable limitation
of these debates is the strong reliance on parametric assumptions and selectiveinfluence manipulations that rarely receive direct test. Here we take a different approach by examining whether visual working-memory judgments satisfy
the structural constraints implied by a random-scale representation—a general
latent-variable framework from which both SDT and discrete-slots models can
be derived. In Experiments 1a and 1b, multiple-alternative forced-choice judgments conformed to these constraints, allowing the reconstruction of single-item
ROC functions without response-bias manipulations. The reconstructed ROC
functions were curved and asymmetric, contradicting the linear predictions of
discrete-slots accounts. Experiment 2 provided a complementary failure case,
showing that random-scale constraints break down precisely when their theoretical conditions are not met. Experiment 3 extended the findings to item-location
bindings in change detection, again yielding an asymmetric ROC function that
neither equal-variance SDT nor discrete-slots models can accommodate. Together, the results show that visual working-memory judgments respect the general assumptions underlying SDT while undermining the core commitments of
discrete-slots theories
Social Asymmetry and Risk of Morbidity and Mortality
No full textImportance: Social asymmetry refers to the discrepancy between subjective loneliness and objective social connections. Although both loneliness and isolation have been linked with risk of premature mortality and morbidity, the association between the 2 is poorly understood./ /
Objective: To explore the associations between social asymmetry and risk of incident morbidity and mortality in a national population cohort. / /
Design, Setting, and Participants: Prospective cohort study using data from wave 4 (2008-2009) of the English Longitudinal Study of Aging (ELSA) as baseline. Participants were aged 50 years and older living in England. Data were analyzed from April to August 2025. / /
Exposures: Social asymmetry was quantified as the residual score from regressing scaled loneliness on scaled social isolation. / /
Main Outcomes and Measures: Incident cardiovascular disease (CVD), chronic obstructive pulmonary disease (COPD), dementia, and all-cause mortality, through data linkage to hospital episode statistics and mortality registry data up to 2024. / /
Results: Of 7845 participants (mean [SD] age at baseline, 65.5 [9.5] years; 4283 [54.6%] women; 7694 [98.1%] White and 151 [1.9%] other race or ethnicity) with a mean (SD) follow-up period of 13.6 (4.2) years, 2775 deaths and 2415 CVD, 989 COPD, and 710 dementia cases were recorded. Higher social asymmetry (higher loneliness than estimated by isolation) was associated with increased risk of CVD (hazard ratio [HR], 1.06; 95% CI, 1.02-1.10) and all-cause mortality (HR, 1.04; 95% CI, 1.01-1.06). Compared with those in the socially resilient group, those in the socially vulnerable group had a higher risk of all-cause mortality (HR, 1.13; 95% CI, 1.04-1.22), CVD (HR, 1.16; 95% CI, 1.04-1.30), and COPD (HR, 1.21; 95% CI, 1.04-1.42). Compared with the concordant low lonely group (low loneliness, low isolation), participants in the concordant high lonely group (high loneliness, high isolation) had an increased risk for all health outcomes investigated, while those in the discordant susceptible category (high loneliness, low isolation) had an increased risk for CVD and mortality; the discordant robust group (low loneliness, high isolation) had no association for any outcomes except for dementia./ /
Conclusions and Relevance: In this cohort study, higher social asymmetry was associated with increased risk of incident morbidity and mortality, emphasizing the importance of evaluating both loneliness and isolation in studies of health outcomes. Future interventions could leverage this novel measurement to identify high-risk groups to target
Chronic Pain and Hypertension and Mediation Role of Inflammation and Depression
No full textBACKGROUND:
The association between chronic pain and incident hypertension is unclear. This study aimed to investigate the associations between different pain characteristics (pain type, location, and spread) and incident hypertension, and whether they were mediated by inflammation, depression, or medication. / /
METHODS:
In a cohort study of 206 963 UK Biobank participants, multivariable Cox-proportional regression was used to investigate the associations between pain at baseline, measured via a touchscreen questionnaire, and incident hypertension ascertained from linkage to health records. Mediation analysis was conducted to estimate the percentage of the association mediated by inflammation, depression, and medications. / /
RESULTS:
Over a median follow-up of 13.5 years, 19 911 (9.62%) participants developed hypertension. Compared with no pain, those with short-term pain (hazard ratio, 1.10 [95% CI, 1.03–1.17]), chronic localized pain (hazard ratio, 1.20 [95% CI, 1.14–1.26]), and chronic widespread pain (hazard ratio, 1.75 [95% CI, 1.52–2.00]) had an increased risk of hypertension. A dose-relationship also existed between the number of chronic pain sites and hypertension. Chronic headache, neck, back, abdominal, hip, and widespread pain were all associated with an increased risk of hypertension, as was chronic musculoskeletal pain. Together, depression (11.3%) and inflammation (0.4%), as measured by C-reactive protein, mediated 11.7% of the association between chronic pain and hypertension. / /
CONCLUSIONS:
People with chronic pain are at higher risk of developing hypertension, and this is partly explained by inflammation and depression. These findings reinforce the need for pain management, and the monitoring and early detection of hypertension
Biofluid biomarkers in Alzheimer’s disease and other neurodegenerative dementias
No full textBiofluid-based biomarkers have transformed neurodegenerative disease research and care, providing insights into the molecular underpinnings of Alzheimer's disease (AD) and other neurodegenerative dementias. This Review provides an update on recent developments in biofluid-based biomarkers for amyloid-β (Aβ) pathology, tau pathology, neurodegeneration, glial reactivity, α-synuclein pathology, TAR DNA-binding protein 43 (TDP-43) pathology, synaptic pathophysiology and cerebrovascular disease-pathologies and processes that are all relevant to neurodegenerative dementias. Complementing longstanding cerebrospinal assays, improved technologies now facilitate the detection of molecules linked to neurodegenerative brain changes at very low concentrations in the blood. This promises to complement the clinical evaluation of suspected neurodegenerative disease in healthcare with molecular phenotyping biomarkers that will help to link the clinical symptoms to ongoing pathophysiological processes in the brain and improve how patients are referred to specialty clinics for initiation and monitoring of molecularly targeted treatments. Clinically relevant breakthroughs such as the use of anti-Aβ monoclonal antibodies to address Aβ pathology in AD serve as important proof-of-concept examples of how the field is advancing toward molecularly informed prevention and treatment. This Review provides an overview of the most established biofluid-based biomarkers currently in use and offers practical guidance on their interpretation and implementation in clinical settings
Whole-brain in situ postmortem MR imaging using a combination of sequences for cortical lesion detection in multiple sclerosis
No full textPURPOSE: Cortical lesions are specific for multiple sclerosis but remain challenging to detect using magnetic resonance imaging (MRI). While numerous MR sequences have been evaluated individually, their combined performance in clinical routine settings has not been validated histopathologically. This study aimed to determine the detection rate of histopathologically validated cortical lesions using combined assessment of multiple MRI sequences in postmortem in situ imaging. MATERIAL AND METHODS: Five MRI sequences [phase-sensitive inversion recovery (PSIR), double inversion recovery (DIR), fluid-attenuated inversion recovery (FLAIR), 3D-T₁, and proton density (PD)/T₂] were acquired at 3 T for 18 patients with multiple sclerosis using postmortem in situ whole-brain imaging. A total of 66 tissue samples were collected and stained for myelin to identify cortical lesions types I-IV. Cortical lesions were assessed prospectively on MRI (blinded to histopathology) and retrospectively (with histopathological knowledge) using combined sequence evaluation and consensus reading. RESULTS: Histopathological analysis revealed 115 cortical lesions in 16/18 patients (4 type I, 43 type II, 61 type III, 7 type IV). Prospective assessment using all MRI sequences combined detected 20/115 (17.4%) cortical lesions with 100% specificity. The combination of DIR and PSIR sequences showed a 43% relative increase in detection compared to conventional sequences. Retrospective assessment with histopathological knowledge increased detection to 46/115 (40.0%) lesions, with DIR and PSIR in combination providing an 18% relative improvement. CONCLUSION: Despite using advanced MRI sequences in a highly controlled postmortem setting, cortical lesion detection remains limited at 17.4%. The combination of DIR and PSIR sequences provides the most effective approach, significantly outperforming conventional sequences. These findings establish a reference benchmark for cortical lesion detection rates and highlight persistent limitations of current MRI technology for identifying cortical pathology in multiple sclerosis
Adoption of food safety measures in smallholder dairy farms in Kenya: Implications for milk safety and public health
No full textDemand for animal-source foods (ASF) is growing globally, and the consumption can improve food and nutrition security. However, there are growing food safety risks associated with milk contamination. Studies assessing food safety measures (FSM) at the farm level are still limited. This study investigated FSM adoption in Kenyan smallholder dairy farms. Data were collected through focus group discussions (FGDs) and a farm survey involving 652 farmers, which considered 11 milking hygiene, 6 milk storage, 6 environmental hygiene, and 7 animal health measures.
The Food Safety Index (FSI) was 51.67%, which reveals average FSM adoption and a good agricultural practices (GAPs) compliance gap that exposes consumers to public health risks. FSM adoption was associated with participation in formal and/or informal milk value chains, socio-economic and demographic factors, knowledge of milk quality standards and regulations, farm biophysical conditions, market dynamics and institutional factors.
There is a need for increasing FSM adoption through improving farmers' knowledge, supporting their access to financial resources, and providing infrastructure and services, including roads, inputs, extension and animal health services. Policymakers should design and implement policies that address specific farmers' needs. There is also a need to provide economic incentives and ensure that the market rewards dairy producers who adopt high levels of FSM that lead to safer milk. Finally, promoting the One Health approach can help farmers address human, environmental and animal health risks, which can reduce food safety risks in dairy value chains
The Suppressibility of Otoacoustic Emissions and Loudness by Low-Frequency Biasing Tones as a Function of Probe Level
No full textPurpose:
Biasing of the cochlear partition by tones below 100 Hz is commonly used to investigate cochlear non-linearity. Their long periodicity allows resolution of the suppression of cochlear responses as the partition is displaced periodically away from its resting position. The purpose of this study was to quantify by how much the biasing tone (BT) level needed to be increased to keep an equal suppression depth in OAE and an equal criterion suppression of loudness while the levels of the response-evoking stimuli were increased.
//
Method:
Suppression-period patterns were obtained for the distortion-product and stimulus-frequency otoacoustic emissions (DPOAE: N = 8 ears, SFOAE: N = 6 ears) using a 55-Hz BT, conditions in which the primary frequencies were at least 3 octaves above the BT frequency. A prior search for primary parameters that allowed the highest recording SNR was conducted, including an optimization of the lower primary tone level (L1) for the DPOAE. The BT level was adjusted so that the maximum suppression depth was kept constant at 9 dB for both OAEs, for various primary levels. Also, the BT level required to reach an equal criterion suppression in the loudness of 1- and 2-kHz tone-pip probes was measured psychoacoustically (N = 4) at various probe levels using the same BT.
//
Results:
The increase in suppressor level per increase in probe level was similar (~ 0.4 dB/dB) for equal-loudness suppression of the tone pips, 9-dB suppression of the SFOAE, and the 2F1–F2 DPOAE, when the increase in L1 was considered. Average BT levels increased linearly over the whole range of probe levels tested.
//
Conclusion:
As the observed iso-suppression rate is broadly consistent with the growth of basilar membrane vibration with increasing stimulus level in the active region of the traveling wave, we conclude that equal suppression of cochlear responses during partition biasing occurs when bias displacement grows in proportion to the probe’s traveling wave amplitude in its active region
Cardiorespiratory fitness, grip strength and depression symptoms: A Mendelian Randomization study
No full textObjective: To assess the impact of cardiorespiratory fitness (CRF) and muscle strength on depression and individual depression symptoms. /
Methods: Mendelian randomisation (MR) analysis was conducted in up to 341,326 participants of European ancestry from UK Biobank (aged 37–73 years). Genetic variants from previous genome-wide association studies (GWAS) of CRF and grip strength (to proxy overall muscle strength) were utilised to instrument exposures. A broad depression phenotype based on self-report and hospital records, as well as individual measures of depression symptoms from the Patient Health Questionnaire-9 (PHQ-9) were used as outcomes. Analysis was repeated stratifying by sex and using summary statistics from a major depressive disorder (MDD) GWAS. /
Results: There was no clear evidence for association between CRF and any depression outcome. There was robust evidence suggesting greater grip was associated with lower odds of broad depression (OR per 0.1 kg increase in weight adjusted grip: 0.86, 95% CI:0.80,0.93), as well as the PHQ-9 items appetite changes (OR:0.56, 95% CI:0.49,0.65), and anhedonia (OR:0.79, 95% CI:0.69,0.90), a core symptom of depression. There was also some evidence for associations between greater grip and lower odds of depressed mood (OR:0.85, 95% CI:0.74,0.97), psychomotor changes (OR:0.79, 95% CI:0.64,0.97), fatigue (OR:0.83, 95% CI:0.74,0.93) and concentration problems (OR:0.85, 95% CI:0.74,0.98) in the MR-inverse variance weighted analysis. Effects were mostly driven by stronger associations in females and results replicated in the two-sample MR for MDD. /
Conclusion: Muscle strength may represent an important modifiable factor for preventing and treating depression and several specific symptoms, including core symptoms such as anhedonia