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Association of environmental noise exposure with cortisol levels in children from eight European birth cohorts
No full textEnvironmental noise is a major environmental risk factor for public health. According to the noise reaction model the release of stress hormones like cortisol in response to noise exposure, plays a key role in the development of noise-induced health effects. We aimed to study the association between environmental noise with both acute (UCC) and cumulative (HCC) cortisol levels in children 5–12 years of age. To do so, we analysed data from the HELIX cohort –with spot UCC data- and from the Generation R and INMA cohorts (Gipuzkoa and Sabadell) –with HCC data. The analytical sample involved: 750 HELIX children (mean age = 7.75), 1326 Generation R children (mean age = 6.06), 111 INMA-Sabadell children (mean age = 8.75) and 288 INMA-Gipuzkoa children (mean age = 7.85). Day-evening-night equivalent (Lden) environmental noise exposure during the year of the follow-up was estimated in the addresses of participants, using existing noise maps. Directed acyclic graphs (DAGs) were used to identify appropriate covariates and reduce the chance for biased estimation. We used mixed-effects modelling and linear modelling to examine the association between Lden and cortisol concentration using complete case analyses. None of the models reached the statistical significance. We observed no correlation between HCC and UCC in INMA-Sabadell participants, for whom both urinary and hair cortisol data were available. Future research should prioritize investigating the effects of environmental noise on HCC, as it may serve as a more reliable indicator for assessing associations with chronic exposures. Additionally, future studies on noise-induced health effects in children should incorporate other biomarkers of stress and chronic inflammation to provide a more comprehensive understanding of these associations
Near and far future conservation, land use, and land cover interactions around the wider Etosha landscape, north-central Namibia
No full textRecent conservation efforts have resulted in the growth of protected and conserved areas as a land use across African drylands. However, land use and land cover change (LULCC) associated with habitat fragmentation continues to be a substantive driver of biodiversity loss in multiple-use landscapes. This study highlights the significance of perspectives from diverse stakeholders in understanding LULCC in a southern African dryland where the coverage of protected and conserved areas is increasing. The study models future land cover change scenarios and assesses their alignment with the Sustainable Development Goals (SDG) Agenda 2030 and the African Union (AU) Agenda 2063. Three scenarios representing business-as-usual conditions, conservation and livestock production, and agricultural and livestock production are outlined. Under business-as-usual conditions, protected areas are conserved and built-up areas expand. However, land degradation occurs where people are concentrated around key resource areas. In a scenario focused on conservation and livestock production, conservation initiatives are strengthened, but expansion of shrublands occurs in livestock-dominated areas that are not well managed. In a scenario focused on agricultural and livestock production, farms grow but their expansion within protected areas causes human-wildlife conflicts. Desirable near and far futures — characterised by environmental integrity, human-wildlife coexistence, and an equitable, thriving wildlife-based economy — are seen as attainable through coordinated land-based activities and the implementation of community-based conservation legislation. Outputs from this study demonstrate the value of a stakeholder-led approach in tackling conservation challenges and in planning for a sustainable future for an arid region heavily reliant on land-based livelihoods
EEG markers of cognitive performance in bipolar disorder – a systematic review
No full textBackground
People with bipolar disorder (BD) may experience impairing cognitive deficits, even in remission. Electroencephalographic (EEG) measures can depict neurophysiological activity with high temporal resolution. They could therefore be an adequate method to pinpoint the cognitive impairments in BD, facilitating understanding of when exactly the cognitive processing is disrupted and what neurophysiological systems are involved. In the absence of a previous literature examination, this systematic review aimed to synthesize the evidence of associations between EEG and cognitive measures to identify electrophysiological markers of cognitive performance in BD.
Methods
A systematic search across PubMed, EMBASE, APA PsycInfo and Cochrane Library until November 2023 was undertaken to identify studies in which a direct correlation between any continuous EEG measure and any continuous cognitive measure in participants with BD was reported. A narrative synthesis approach was used to present the identified correlations, across five cognitive (attention and processing speed, working memory, episodic memory, executive function, and intellectual capacity) and four EEG domains (event-related potentials (ERP), spectral, connectivity and other measures).
Results
A total of 16 articles describing 15 studies were included in the review. Six studies identified significant correlations. Most significant correlations were reported between ERP measures and attention and processing speed performance, several between ERP measures and executive functioning and one within the working memory and the intellectual capacity domain respectively. However, most of the identified significant correlations were conflicting within (different measures or mood states) and across studies with no consistent significant correlation across studies. The majority of identified correlations were non-significant.
Conclusions
As yet no robust EEG markers of cognitive performance in people with BD are known. This review highlights the heterogeneity in measures and participant characteristics between studies and the need for standardization. Further studies with homogeneous methods and participant groups may help to establish consistent associations
Multicomponent interventions designed to support adherence to guideline-recommended therapy in patients with peripheral artery disease: a scoping review
No full textAdherence to guideline-recommended therapies for peripheral artery disease (PAD), including pharmacotherapy (antiplatelet, lipid-lowering, and antihypertensive agents) and lifestyle modifications (smoking cessation, diet, weight management, and physical activity) remains low. Though single-component interventions targeting smoking cessation, exercise, or medication adherence show some efficacy, comprehensive multicomponent interventions are vital for addressing the complexity of PAD management. This review systematically synthesized multicomponent interventions for patients with PAD. A systematic search was conducted in Embase, MEDLINE, Cochrane Library, APA PsycINFO, CINAHL, Web of Science Core Collection, ProQuest, and Google Scholar to identify primary research describing multicomponent interventions supporting PAD treatment adherence, published between 2007 and 2024. A narrative synthesis was reported using the Template for Intervention Description and Replication (TIDieR) checklist and the behavioral change techniques (BCT) taxonomy. Out of 15 studies (2462 patients, 60.4% men) included in this review, only two addressed all guideline-recommended treatment aspects. Key intervention components included structured exercise (12/15) and education programs (10/15). Most interventions were delivered by multidisciplinary teams in hospital settings over 3 months. Only one study employed behavioral theory in its development, and most interventions (13/15) focused on the BCT ‘instructions on how to perform a behavior’ rather than diverse BCTs. No interventions significantly increased adherence to all PAD therapies. Few studies measured the intervention’s impact on adherence, making it difficult to determine effective intervention characteristics. Most interventions lacked behavioral science approaches and were not designed to address specific adherence determinants. Future interventions should incorporate these elements to effectively address patients’ needs. Open Science Framework Registry ID: osf.io/7xqz
Differential privacy via distributionally robust optimization
No full textIn recent years, differential privacy has emerged as the de facto standard for sharing statistics of data sets while limiting the disclosure of private information about the involved individuals. This is achieved by randomly perturbing the statistics to be published, which in turn, leads to a privacy-accuracy trade-off; larger perturbations provide stronger privacy guarantees, but they result in less accurate statistics that offer lower utility to the recipients. Of particular interest are, therefore, optimal mechanisms that provide the highest accuracy for a preselected level of privacy. To date, work in this area has focused on specifying families of perturbations a priori and subsequently proving their asymptotic and/or best-in-class optimality. In this paper, we develop a class of mechanisms that enjoy nonasymptotic and unconditional optimality guarantees. To this end, we formulate the mechanism design problem as an infinite-dimensional distributionally robust optimization problem. We show that the problem affords a strong dual, and we exploit this duality to develop converging hierarchies of finite-dimensional upper- and lower-bounding problems. Our upper (primal) bounds correspond to implementable perturbations whose suboptimality can be bounded by our lower (dual) bounds. Both bounding problems can be solved within seconds via cutting-plane techniques that exploit the inherent problem structure. Our numerical experiments demonstrate that our perturbations can outperform the previously best results from the literature on artificial as well as standard benchmark problems
Elastic buckling formulae for web crippling of square and rectangular hollow sections under concentrated transverse forces
No full textFormulae for determining the elastic buckling loads of structural steel rectangular hollow sections subjected
to concentrated transverse forces are presented herein. The predicted elastic buckling load is bounded by a
theoretical lower bound, where only the material within the bearing length is mobilised, and a practical upper
bound, where the adjacent material is mobilised to its maximum extent. The lower bound is the elastic buckling
load of a wide plate with a width equal to the bearing length and a length equal to the web depth, while
the upper bound is determined from finite element (FE) analyses of various representative loading scenarios.
The level of mobilisation of adjacent material (i.e., where a specific case lies between the lower and upper
bounds) is quantified by introducing a coefficient that is calibrated through FE analyses in the commercial
package ABAQUS. The rotational stiffness afforded to the webs by the flanges is also captured. The four loading
scenarios defined in the North American Specification and Australian/New Zealand Standard for the design
of cold-formed steel structures, namely the Interior-Two-Flange (ITF), End-Two-Flange (ETF), Interior-One Flange (IOF) and End-One-Flange (EOF) loading conditions, alongside their transitional cases, are considered.
Rectangular hollow sections with a broad spectrum of cross-sectional geometric proportions and bearing lengths
encompassing the aforementioned loading conditions are considered. It is found that the developed formulae
for predicting the elastic buckling loads under concentrated transverse forces provide accurate results that are
typically within 5% of the numerical values. Hence, the developed formulae can be employed as a convenient
alternative to numerical methods in advanced structural design methodologies, such as the Direct Strength
Method (DSM) and the Continuous Strength Method (CSM)
Fibular length and vital capacity in the multinational Burden of Obstructive Lung Disease follow-up study
No full textIt is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJ online
Linear groups irreducible on exterior powers
No full textLet V be a finite-dimensional vector space over a finite or algebraically closed field. We classify subgroups G of GL(V ) with the property that G acts irreducibly on all exterior powers of V
Matrix groups and regular semigroups
No full textLet Tn denote the tranformation semigroup consisting of all maps from [n] → [n], where [n] = {1, . . . , n}. In 2009, Ara´ujo, Mitchell and Schneider gave a classification of subgroups G ≤ Sn such that ⟨G, a⟩ is a regular semigroup for all a ∈ Tn,
showing that for n ≥ 10, the only possibilities for G are An and Sn. We investigate the analogous problem for linear groups over finite fields, raised by Ara´ujo and Cameron:
classify the subgroups of GLn(q) such that ⟨G, A⟩ is a regular semigroup for all matrices A in the matrix semigroup Mn(q). We obtain a representation theoretic criterion for
such groups G, and exhibit a connection with the action of G on the exterior powers of the underlying space Fnq . As a consequence we prove the existence of several families of
subgroups G of GLn(q) for arbitrary n with the property that ⟨G, A⟩ is regular for all A, in contrast with the previously mentioned result for Tn
Evolution and transmission dynamics of wild poliovirus in Pakistan and Afghanistan (2012-2023)
No full textDespite concerted global vaccination efforts, wild poliovirus remains endemic in two countries in 2024, Pakistan and Afghanistan. This study uses phylogeographic analysis of poliovirus genetic and epidemiological data from clinical and wastewater surveillance to identify the causes of poliovirus persistence and routes of spread over the last decade (2012 to 2023). Poliovirus genetic diversity declined after 2020, with one of two major genetic clusters dying out, and recent detections are now closely related genetically. High-risk and hard-to-access regions have sustained polio transmission over the past decade, even when interrupted elsewhere. Karachi, one of the most densely populated cities globally, has acted as a hub for the amplification and spread of poliovirus to other regions, many of which we show to be dead-end for onwards transmission despite frequent virus detection. Phylogenetic analysis has long been central to the polio surveillance network, and advancing the approaches used can provide critical epidemiological insights to accelerate eradication efforts