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Acute and chronic effects of an intervention aiming to reduce prolonged sitting on glucose regulation in individuals with dysglycaemia
No full textAcute studies have consistently demonstrated small-to-medium glycaemic responses to breaking prolonged sitting, yet it’s not known whether acute effects are maintained following a period of intervention or whether behavioural interventions lead to sustained benefits. A single arm, 4-week intervention with pre and post ‘two-arm’ randomised cross-over conditions, study was conducted to investigate whether reducing prolonged sitting in free-living affects acute and chronic glucose and insulin responses. Adults aged 40-75 years living with overweight or obesity with an elevated HbA1c (5.7-7.5%) underwent four experimental conditions (two prolonged sitting [CON], two sitting with self-paced light upright movement breaks [LUMB]) in a randomised order. One of each condition was conducted before and after the intervention. A total of 33 participants completed the study. There was no change in sitting or glucose/insulin levels over the 4-week intervention. However, glucose and insulin were reduced acutely in the LUMB conditions compared with CON (glucose [mmol/L]: CON: 5.77 [5.51; 6.02], LUMB: 5.55 [5.30; 5.81], p = 0.006, insulin [mIU/L]: (CON: 77.70 [61.58; 93.83], LUMB: 61.28 [51.19; 71.38], p = <0.001); these responses did not change over time. In conclusion, the intervention did not lead to reduced sitting time or chronic changes to postprandial metabolism.</p
Dynamic capabilities and international entrepreneurship: Towards a better understanding
No full textThe dynamic capabilities view (DCV) and international entrepreneurship perspective (IEP) are major, relatively recent advances in international business (IB), strategy, and entrepreneurship. Despite their different disciplinary backgrounds—DCV in evolutionary economics and the resource-based view and the IEP in entrepreneurship and marketing—they share many themes and ideas in common, which have only recently started being acknowledged. In this article, we explore the contribution of, and interrelationship between, the two approaches, their limitations and scope for further development. Key insights include that the DCV helps complement IEP in terms of its focus on value co-creation and the requisite reconfiguration of resources to help bring about value capture. In turn, IEP complements DCV in terms of its exploration of the nature of opportunities and the entrepreneurial capabilities to sense these, and in terms of providing supporting evidence about these capabilities.</p
Comparing the diagnostic accuracy of cerebrospinal fluid biomarkers for Alzheimer’s disease: A novel meta‐analysis model
No full textBackgroundThe emergence of new biomarkers for Alzheimer’s disease is accompanied by the urgent need to evaluate their diagnostic performance in comparison to existing technologies. Meta‐analysis methods make best use of the available evidence by synthesizing all relevant published studies. Meta‐analytic models that estimate comparative diagnostic accuracy are key to informing healthcare decision‐making around which tests should be used in clinical practice. To produce robust and precise estimates of sensitivity and specificity, models must take into account associations between multiple tests evaluated in the same patient group.MethodA novel Bayesian meta‐analysis model for jointly synthesizing accuracy data on two diagnostic tests was developed using a motivating example in Alzheimer’s disease dementia. A statistical technique known as a copula was used to flexibly capture the associations between the two tests. Comparative diagnostic accuracy data was sourced through electronic searching of The Cochrane Library. The model was fit to studies comparing the diagnostic accuracy of cerebrospinal fluid (CSF) amyloid‐β 42 (Aβ42) and total tau (t‐tau) to detect patients with mild cognitive impairment who would convert to Alzheimer’s disease dementia.ResultCSF Aβ42 (80.6%; 95% credible interval [CrI] 70.8%, 88.3%) was more sensitive to detect Alzheimer’s disease dementia than CSF t‐tau (74.6%; 95% CrI 65.4%, 82.2%). However, CSF t‐tau demonstrated slightly higher specificity (75.5%; 95% CrI 64.9%, 84.4%) than CSF Aβ42 72.6% (95% CrI: 62.9%, 81.2%). In comparison to the meta‐regression approach currently recommended by evidence synthesis guidelines, which ignores associations between tests, the newly proposed model led to increased precision around summary sensitivity and specificity estimates.ConclusionThe proposed model reduces uncertainty around summary test accuracy, aiding decision‐making around diagnostic strategies for Alzheimer’s disease dementia. This novel methodological development is applicable to a range of diagnostic tests for Alzheimer’s disease, including newly emerging blood‐based biomarkers. Continued development of early and minimally‐invasive diagnostic biomarkers will require comprehensive evaluation in the context of existing tests, using appropriate statistical models that capture associations between tests.</p
ESG Risk and Market Return Predictability: New Evidence from the Eurozone
No full textThis study examines the predictive power of incident-based Environmental, Social and Governance (ESG) risk on the Eurozone stock market returns using a forecast combination method. We find that our constructed indicator shows significant return predictability from both a statistical and economic perspective, with an out-of-sample CER gain of 4.55% and a Sharpe ratio of 0.43, consistently outperforming the mean benchmark. Moreover, we find that the predictive power is concentrated during non-expansion periods. We attribute this mechanism to the firm's fundamentals, cash flow and discount rate channels. Our findings highlight the value of ESG information for investors.</p
Numerical modelling of thermal fatigue at pipe mixing points in nuclear power plants
No full textIn nuclear power plants, thermal fatigue can occur at pipe mixing points where hot and cold water combine, leading to failure at these critical locations. This study investigates the effect of temperature fluctuations on fatigue failure at critical locations and welded joints, which has received limited attention in previous research. A numerical approach was used, starting with highly-resolved unsteady conjugate heat transfer simulations to assess heat flux at the pipe wall. This was followed by structural analysis using the finite element method, and finally, a fatigue assessment to predict failure locations and estimate component lifespan. Temperature differences of 80 °C and 160 °C were investigated at the different weld locations. Results showed that at a temperature difference of 160 °C between the main pipe and the branch pipe, a full penetration butt weld would fail after 1462 to 19,119 h. A shorter failure time was observed at the stress concentration area upstream of the T-junction under the same conditions. These findings were applied to the well-documented 1998 failure at the Civaux1 plant in France, to help understand the potential causes of that failure.</p
Overdensity of Lyman-break galaxy candidates around hot-dust-obscured galaxies
No full textHot dust-obscured galaxies (hot DOGs) are a family of hyper-luminous, heavily obscured quasars. A number of studies based on the identification of companions at optical to far-infrared (FIR) wavelengths have shown that these objects reside in significantly overdense regions of the Universe. Here we present further characterisation of their environments by studying the surface density of Lyman break galaxy (LBG) candidates in the vicinity of three hot DOGs. For two of them, WISE J041010.60–091305.2 (W0410–0913) at z = 3.631 and WISE J083153.25+014010.8 (W0831+0140) at z = 3.912, we identify the candidate LBG companions using deep observations obtained with Baade/IMACS. For the third, WISE J224607.56–052634.9 (W2246–0526) at z = 4.601, we reanalyse previously published data obtained with Gemini-S/GMOS-S. We optimise the LBG photometric selection criteria at the redshift of each target using the COSMOS2020 catalog. When comparing the density of LBG candidates found in the vicinity of these hot DOGs with that in the COSMOS2020 catalog, we find overdensities of δ = 1.83 ± 0.08 (δ′ = 7.49 ± 0.68), δ = 4.67 ± 0.21 (δ′ = 29.17 ± 2.21), and δ = 2.36 ± 0.25 (δ′ = 11.60 ± 1.96) around W0410–0913, W0831+0140, and W2246–0526, respectively, without (with) contamination correction. Additionally, we find that the overdensities are centrally concentrated around each hot DOG. Our analysis also reveals that the overdensity of the fields surrounding W0410–0913 and W0831+0140 declines steeply beyond physical scales of ∼2 Mpc. If these overdensities evolve into clusters by z = 0, the present results suggest that the hot DOG may correspond to the early formation stages of the brightest cluster galaxy. We were unable to determine whether or not this is also the case for W2246–0526 due to the smaller field of view (FOV) of the GMOS-S observations. Our results imply that hot DOGs may be excellent tracers of protoclusters.</p
The diagnostic characteristics and reliability of radiological methods used in the assessment of scaphoid fracture union
No full textAimsTo evaluate the diagnostic characteristics and reliability of radiological methods used to assess scaphoid fracture union through a systematic review and meta-analysis.MethodsMEDLINE, Embase, and the Cochrane Library were searched from inception to June 2022. Any study reporting data on the diagnostic characteristics and/or the reliability of radiological methods assessing scaphoid union was included. Data were extracted and checked for accuracy and completeness by pairs of reviewers. Methodological quality was assessed using the QUADAS-2 tool.ResultsA total of 13 studies were included, which were three assessed radiographs alone, six CT alone, and four radiographs + CT. Diagnostic sensitivity was assessed by CT in three studies (0.78, 0.78, and 0.73) and by radiographs in two studies (0.65, 0.75). Diagnostic specificity was assessed by CT in three studies (0.96, 0.8, 0.4) and by radiographs in two studies (0.67, 0.4). Interobserver reliability was assessed for radiographs by seven studies (two fair, four moderate, and one substantial) and for CT in nine studies (one fair, one moderate, six substantial, and one almost perfect).ConclusionThere is evidence to support both the use of CT and radiographs in assessing scaphoid fracture union. Although CT appears superior in terms of both its diagnostic characteristics and reliability, further research is necessary to better define the optimal clinical pathways for patients.Cite this article: Bone Jt Open 2025;6(3):246–253.</p
From Missing Pieces to Masterpieces: Image Completion with Context-Adaptive Diffusion
No full textImage completion is a challenging task, particularly when ensuring that generated content seamlessly integrates with existing parts of an image. While recent diffusion models have shown promise, they often struggle with maintaining coherence between known and unknown (missing) regions. This issue arises from the lack of explicit spatial and semantic alignment during the diffusion process, resulting in content that does not smoothly integrate with the original image. Additionally, diffusion models typically rely on global learned distributions rather than localized features, leading to inconsistencies between the generated and existing image parts. In this work, we propose ConFill, a novel framework that introduces a Context-Adaptive Discrepancy (CAD) model to ensure that intermediate distributions of known and unknown regions are closely aligned throughout the diffusion process. By incorporating CAD, our model progressively reduces discrepancies between generated and original images at each diffusion step, leading to contextually aligned completion. Moreover, ConFill uses a new Dynamic Sampling mechanism that adaptively increases the sampling rate in regions with high reconstruction complexity. This approach enables precise adjustments, enhancing detail and integration in restored areas. Extensive experiments demonstrate that ConFill outperforms current methods, setting a new benchmark in image completion.</p
Growth of Oxygen Minimum Zones May Indicate Approach of Global Anoxia
No full textThe dynamics of large-scale components of the Earth climate system (tipping elements), particularly the identification of their possible critical transitions and the proximity to the corresponding tipping points, has been attracting considerable attention recently. In this paper, we focus on one specific tipping element, namely ocean anoxia. It has been shown previously that a sufficiently large, ‘over-critical’ increase in the average water temperature can disrupt oxygen production by phytoplankton photosynthesis, hence crossing the tipping point, which would lead to global anoxia. Here, using a conceptual mathematical model of the plankton–oxygen dynamics, we show that this tipping point of global oxygen depletion is going to be preceded by an additional, second tipping point when the Oxygen Minimum Zones (OMZs) start growing. The OMZ growth can, therefore, be regarded as a spatially explicit early warning signal of the global oxygen catastrophe. Interestingly, there is growing empirical evidence that the OMZs have indeed been growing in different parts of the ocean over the last few decades. Thus, this observed OMZ growth may indicate that the second tipping point has already been crossed, and hence, the first tipping point of global ocean anoxia may now be very close.</p
Sex-Specific Association of Myocardial Fibrosis With Mortality in Patients With Aortic Stenosis
No full textImportanceMyocardial fibrosis in aortic stenosis (AS) may exhibit sex differences. However, its prognostic significance in women with AS remains unclear.ObjectiveTo investigate sex differences in myocardial fibrosis assessed by cardiovascular magnetic resonance (CMR) and evaluate its prognostic value in women and men with AS.Design, Setting, and ParticipantsPatients with severe AS who underwent CMR before aortic valve replacement (AVR) were prospectively enrolled from 13 international sites between March 2011 and September 2021. Myocardial fibrosis was evaluated using extracellular volume fraction (ECV%) and late gadolinium enhancement (LGE). The main analysis was conducted on patients without obstructive coronary artery disease (CAD), defined as those with no history of myocardial infarction and no concomitant coronary artery bypass grafting. Data were analyzed from December 2023 to February 2024.ExposuresSurgical or transcatheter AVR.Main Outcomes and MeasuresThe primary outcome was post–AVR all-cause mortality and the secondary outcome was cardiovascular mortality.ResultsOf 822 patients, 670 were without obstructive CAD (368 men [55%] and 302 women [45%]). Among these, women and men had a similar age (median, 72 years vs 71 years, respectively), comorbidities, and AS severity. ECV% was similar between sexes; however, women had less LGE (both infarct and noninfarct LGE). After a median follow-up of 3.7 (IQR, 2.1-4.7) years, there were 76 deaths (11.3%), including 29 adjudicated cardiovascular deaths, in patients without obstructive CAD. Increasing ECV% and LGE were associated with higher all-cause and cardiovascular mortality in both sexes. Cox analyses demonstrated that both ECV% and LGE were associated with higher all-cause mortality without significant interaction by sex (women: adjusted hazard ratio [HR], 1.08 per 1% ECV% increase; 95% CI, 1.04-1.12; P </p