Extensive early marine cementation at the seafloor has important environmental implications (e.g., ocean chemistry and atmosphere pCO2), but its driver remains controversial, because many factors ...have been proposed to affect early marine cementation. At the Abu Dhabi coastal area of the Persian Gulf, extensive early marine cementation at the seafloor provides a good modern study case for ancient analogs. Based on petrological (thin section, cathodoluminescence and scanning electron microscope) and geochemical (e.g., δ13CDIC, alkalinity, aragonite saturation) analyses, this study investigates integrated factors from seawater to sediment properties and tests previously proposed explanations about extensive early marine cementation at the seafloor. Results suggest multiple factors involved in the early marine cementation. CaCO3 saturation, small CaCO3 saturation gradient and higher sea level in the early Holocene are consistent with former explanations. A new finding is shallow redox boundary within the seafloor sediment promoting extensive early marine cementation. The formation of shallow redox boundary is unrelated to anoxic bottom water and/or enhanced organic influx, but rather is related to: (a) high salinity under hot and arid climate, and (b) low‐energy and restricted shallow marine settings., These conditions undoubtedly occurred in past shallow and warm epeiric marine seas. This provides new insights into formation mechanism and paleoenvironmental interpretation of ancient extensive early marine cementation at the seafloor on epeiric seas.
Plain Language Summary
Although nowadays (sub) tropical surface seawater is typically CaCO3 oversaturated, extensive early marine cementation is relatively uncommon at the seafloor. This is more complicated by the geological fact that early marine cementation at the seafloor is more common in Calcite seas with lower CaCO3 saturation than Aragonite seas. Understanding key factors controlling early marine cementation at the seafloor is important in many geological aspects, such as sequence stratigraphy, paleoenvironmental interpretation and hydrocarbon exploration. Based on research on a modern subtropical epeiric sea, this study suggests early marine cementation at the seafloor is controlled by both seawater properties and shallow redox boundary within seafloor sediment. The shallow redox boundary is linked to shallow, restricted marine settings and warm, arid climate. The findings herein shed new lights on ancient analogs and related environmental interpretation.
Key Points
Provide insitu seawater and sediment properties associated with extensive early marine seafloor cementation on a modern epeiric sea
Both seawater properties and shallow redox boundary within the seafloor sediment are important for extensive early marine seafloor cementation
The formation of shallow redox boundary is linked to climate and topography of the seafloor, and not necessarily related to ocean oxygen level and organic influx
Abstract
Introduction
Fragility fractures are a major disease burden in the UK. With an ageing population and number of fragility fractures predicted to double in 50 years, prevention in this ...high-risk population needs to be addressed. This audit aimed to examine the assessment of fracture risk in patients presenting with fragility fractures and improve awareness amongst trainee doctors through education.
Methods
A retrospective study was conducted on patients over 65 years admitted with fragility fractures, excluding neck of femur, from January to March 2021 (n = 51). Data was collected on Fracture Risk Assessment Tool (FRAX) scores, dual energy X-ray absorptiometry (DEXA) scans, and risk factors including body mass index (BMI), previous fragility fracture, smoking, alcohol intake, and serum calcium and vitamin D. A teaching seminar for junior doctors was delivered to increase confidence in assessing and managing fragility fractures.
Results
The mean age of patients was 79, with most common presentations being proximal humerus, distal femur and ankle fractures. 46% of patients had a previous fragility fracture. Smoking and alcohol history were documented in 72% and 60% of patients respectively, and 29% had BMIs calculated. 68% had calcium and 45% had vitamin D checked. DEXA scans occurred in 12%, all of whom had osteopenia or osteoporosis. Over half of patients were already on bone protection and 28% were subsequently started on bisphosphonates. A teaching session was delivered to junior doctors (n = 10), leading to improved confidence in assessing fracture risk by 30%, and improved confidence in managing fragility fractures by 35%. Knowledge of FRAX score increased from 62% to 100%.
Conclusion
A significant proportion of the over-65 population are likely to present with fragility fractures. Improving awareness and confidence amongst junior doctors can lead to identification of risk factors and help better prevent and manage fragility fractures in this high-risk population.
Accurate prediction of extrathyroidal extension and subsequent recurrence is crucial in papillary thyroid cancer clinical management. Our aim was to conduct iodine map-based radiomics to predict ...extrathyroidal extension and to explore its prognostic value for recurrence-free survival in papillary thyroid cancer.
A total of 452 patients with papillary thyroid cancer were retrospectively recruited between June 2017 and June 2020. Radiomics features were extracted from noncontrast images, dual-phase mixed images, and iodine maps, respectively. Random forest and least absolute shrinkage and selection operator (LASSO) were applied to build 6 radiomics scores (noncontrast radiomics score_random forest; noncontrast rad-score_LASSO; mixed rad-score_random forest; mixed rad-score_LASSO; iodine radiomics score_random forest; iodine radiomics score_LASSO) respectively. Logistic regression was used to construct 6 radiomics models incorporating 6 radiomics scores with clinical risk factors and to compare them with the clinical model. A radiomics model that achieved the highest performance was presented as a nomogram and assessed by discrimination, calibration, clinical usefulness, and prognosis evaluation.
Iodine radiomics scores performed significantly better than mixed radiomics scores. Both of them outperformed noncontrast radiomics scores. Iodine map-based radiomics models significantly surpassed the clinical model. A radiomics nomogram incorporating size, capsule contact, and iodine radiomics score_random forest was built with the highest performance (training set, area under the curve = 0.78; validation set, area under the curve = 0.84). Stratified analysis confirmed the nomogram stability, especially in group negative for CT-reported extrathyroidal extension (area under the curve = 0.69). Nomogram-predicted extrathyroidal extension risk was an independent predictor of recurrence-free survival. A high risk for extrathyroidal extension portended significantly lower recurrence-free survival than low risk (
< .001).
Iodine map-based radiomics might be a supporting tool for predicting extrathyroidal extension and subsequent recurrence risk in patients with papillary thyroid cancer, thus facilitating clinical decision-making.
Background: Over the past two decades, China has enjoyed impressive economic development, and her citizens have experienced many remarked changes in their lifestyle. These changes are often ...associated with an increase in obesity and chronic disease. Methods: In this meta-analysis, based on nationally representative data, we studied the current prevalence of obesity and the trends in obesity, mortality and morbidity in China. Results: Between 1992 and 2002, the prevalence of overweight and obesity increased in all gender and age groups and in all geographic areas. Using the World Health Organization body mass index cut points, the combined prevalence of overweight and obesity increased from 14.6 to 21.8%. The Chinese obesity standard shows an increase from 20.0 to 29.9%. The annual increase rate was highest in men aged 18-44 years and women aged 45-59 years (approximately 1.6 and 1.0% points, respectively). In general, male subjects, urban residents, and high-income groups had a greater increase. With the increase in overweight and obesity, obesity-, and diet-related chronic diseases (e.g., hypertension, cardiovascular disease (CVD), and type 2 diabetes) also increased over the past decade and became a more important preventable cause of death. Hypertension increased from 14.4% in 1991 to 18.8% in 2002 in adults; in older adults aged 35-74 years, it increased from 19.7 to 28.6%. Between 1993 and 2003, the prevalence of CVD increased from 31.4 to 50.0%; diabetes increased from 1.9 to 5.6%. During 1990-2003, although total mortality rate (per 100 000) decreased, overall the mortality rate and contribution (as percentages) to total death of obesity-related chronic disease increased, in particular, in rural areas. Mortality rate (per 100 000) of CVD increased from 128 to 145 and its contribution to total death, 27 to 32%, in rural areas; the figures decreased slightly in urban areas. The mortality rate of 'nutrition, endocrinology and metabolism-related disease' (NEMD) increased in both rural and urban areas between 1990 and 2000, 8.0 to 10.6 and 4.9 to 5.3, respectively. The current prevalence of hypertension, dyslipidaemia, metabolic syndrome, and diabetes among Chinese adults is approximately 20, 20, 15, and 3%, respectively. Conclusion: The prevalence of overweight and obesity and obesity-related chronic diseases have increased in China in the past decade. Our findings provide useful information for the projection of future trends and the formulation of national strategies and programmes that can address the challenges of the growing obesity and chronic disease epidemic.
How cellular and organismal complexity emerges from combinatorial expression of genes is a central question in biology. High-content phenotyping approaches such as Perturb-seq (single-cell ...RNA-sequencing pooled CRISPR screens) present an opportunity for exploring such genetic interactions (GIs) at scale. Here, we present an analytical framework for interpreting high-dimensional landscapes of cell states (manifolds) constructed from transcriptional phenotypes. We applied this approach to Perturb-seq profiling of strong GIs mined from a growth-based, gain-of-function GI map. Exploration of this manifold enabled ordering of regulatory pathways, principled classification of GIs (e.g., identifying suppressors), and mechanistic elucidation of synergistic interactions, including an unexpected synergy between
and
driving erythroid differentiation. Finally, we applied recommender system machine learning to predict interactions, facilitating exploration of vastly larger GI manifolds.
MR offers by far the most sensitive technique for detecting multiple sclerosis (MS) lesions and has proved to be an important paraclinical tool for diagnosing MS and monitoring therapeutic trials. ...Technologic advances of MR in recent years have dramatically improved our understanding of MS disease. This review will focus on the contribution of MR imaging in MS and provide a discussion of conventional and advanced nonconventional MR techniques with regard to current findings, clinical correlations, and future directions.
Antibacterial adhesives have favorable prospects to inhibit biofilms and secondary caries. The objectives of this study were to investigate the antibacterial effect of dental adhesives containing ...dimethylaminododecyl methacrylate (DMADDM) on different bacteria in controlled multispecies biofilms and its regulating effect on development of biofilm for the first time. Antibacterial material was synthesized, and Streptococcus mutans, Streptococcus gordonii, and Streptococcus sanguinis were chosen to form multispecies biofilms. Lactic acid assay and pH measurement were conducted to study the acid production of controlled multispecies biofilms. Anthrone method and exopolysaccharide (EPS):bacteria volume ratio measured by confocal laser scanning microscopy were performed to determine the EPS production of biofilms. The colony-forming unit counts, scanning electron microscope imaging, and dead:live volume ratio decided by confocal laser scanning microscopy were used to study the biomass change of controlled multispecies biofilms. The TaqMan real-time polymerase chain reaction and fluorescent in situ hybridization imaging were used to study the proportion change in multispecies biofilms of different groups. The results showed that DMADDM-containing adhesive groups slowed the pH drop and decreased the lactic acid production noticeably, especially lactic acid production in the 5% DMADDM group, which decreased 10- to 30-fold compared with control group (P < 0.05). EPS was reduced significantly in 5% DMADDM group (P < 0.05). The DMADDM groups reduced the colony-forming unit counts significantly (P < 0.05) and had higher dead:live volume ratio in biofilms compared with control group (P < 0.05). The proportion of S. mutans decreased steadily in DMADDM-containing groups and continually increased in control group, and the biofilm had a more healthy development tendency after the regulation of DMADDM. In conclusion, the adhesives containing DMADDM had remarkable antimicrobial properties to serve as “bioactive” adhesive materials and revealed its potential value for antibiofilm and anticaries clinical applications.
The Tibetan Plateau is the highest and one of the most demanding environments ever inhabited by humans. We investigated the timing and mechanisms of its initial colonization at the Nwya Devu site, ...located nearly 4600 meters above sea level. This site, dating from 40,000 to 30,000 years ago, is the highest Paleolithic archaeological site yet identified globally. Nwya Devu has yielded an abundant blade tool assemblage, indicating hitherto-unknown capacities for the survival of modern humans who camped in this environment. This site deepens the history of the peopling of the "roof of the world" and the antiquity of human high-altitude occupations more generally.
Non-state owned firms in China grow tremendously with limited support from banks. This provides a unique setting to test how firms in a country with poorly developed financial institutions fund their ...prosperous growth opportunities. This paper compares the use of an important non-formal financial channel, trade credit, between state and non-state owned firms in China. We find that, compared to state owned firms, non-state owned firms use more trade credit. We further show that this higher usage is primarily for financing rather than transactional purposes. The results suggest that, in a country with a poorly developed formal financial sector, firms can support their growth through non-formal financial channels that largely rely on implicit contractual relation.
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