Ooid distribution and fabric in the Miaolingian of Xiaweidian Section, Beijing (North China Platform)

This study is an attempt to describe the distribution and fabric of the Cambrian ooids from the Xuzhuang, Zhangxia and Gushan formations at the Xiaweidian section. The oolitic banks occupy the upper parts of the 3rd order depositional sequences recognized for these formations. Petrographical techniques were applied to describe the sedimentary features of ooid grains. Different characteristics of ooids including size distribution, composition, morphology and the internal and external cortical architecture were taken into consideration. Radial-concentric, micritic, superficial, composite, pseudo-oids, neomorphosed and geopetal ooids are properly studied under the microscope. Different fabrics of ooids have been linked to their different depositional settings, and a variety of sub-environments has been established. The oolitic grain banks are composed mainly of calcite, with noteworthy presence of aragonite and dolomite. The two-fold role of microorganisms during and after the formation of ooids can be recognized under the microscope. The mechanism of ooids fabric modification has been elaborated in detail. Firstly, the dark laminae in several ooids most probably show the remains of filamentous cyanobacteria taking part in the construction of ooids. Secondly, they destroy the cortex through boring, which is then subsequently filled by aragonite. In order to apprehend the sedimentological features of the Miaolingian strata in the Xiaweidian section, this research highlights the distribution of oolites and their resultant fabric in response to relative sea-level variations. The Miaolingian ooids in the Xiaweidian section provide a good reference example of the depositional pattern of oolitic grain banks

BOVA is Superior to sPESI in Identification of High Risk Pulmonary Embolism Patients

Introduction: Prognostic models exist for the purpose of stratifying patients with acute pulmonary embolism. Of these, the Pulmonary Embolism Severity Index (PESI) and the simplified PESI (sPESI) are the most well-known, although more recent composite models, like the BOVA score, are now being studied and implemented. Comparative efficacy of these scores to predict long term mortality is not well established. Methods: We performed a retrospective analysis of all consecutive patients diagnosed with PE using computed tomography scan from 2014-2016 at an urban tertiary-referral medical center. Cox proportional hazard analyses were performed to compare the performance of two prognostic models – sPESI and BOVA – to predict all-cause in-hospital and cumulative one-year mortality. Results: The all-cause in-hospital mortality rate was 6.0%, and cumulative one-year mortality rate was 21.3%. In adjusted analyses, a BOVA score \u3e4 was significantly associated with an increased in-hospital mortality (HR 3.5, 95% CI: 1.4-9.0, p = 0.009) and one-year mortality (HR 2.0, 95% CI: 1.0-3.9, p = 0.04), as compared to a BOVA score \u3c4. However, the sPESI (p = 0.14) did not show a significant association with one-year mortality. In identifying in-hospital mortality, the sPESI had high sensitivity (100%) and low specificity (10.1%), whereas the BOVA score had low sensitivity (20.0%) and high specificity (92.7%). Similar trends were seen for one-year mortality. Conclusion: In this study, a high BOVA score was found to be the best predictor of both short and long-term mortality in PE patients. A low sPESI score identified with high sensitivity patients with low-risk PEs

Melatonin and health: an umbrella review of health outcomes and biological mechanisms of action

BackgroundOur aims were to evaluate critically the evidence from systematic reviews as well as narrative reviews of the effects of melatonin (MLT) on health and to identify the potential mechanisms of action involved.MethodsAn umbrella review of the evidence across systematic reviews and narrative reviews of endogenous and exogenous (supplementation) MLT was undertaken. The Oxman checklist for assessing the methodological quality of the included systematic reviews was utilised. The following databases were searched: MEDLINE, EMBASE, Web of Science, CENTRAL, PsycINFO and CINAHL. In addition, reference lists were screened. We included reviews of the effects of MLT on any type of health-related outcome measure.ResultsAltogether, 195 reviews met the inclusion criteria. Most were of low methodological quality (mean -4.5, standard deviation 6.7). Of those, 164 did not pool the data and were synthesised narratively (qualitatively) whereas the remaining 31 used meta-analytic techniques and were synthesised quantitatively. Seven meta-analyses were significant with P values less than 0.001 under the random-effects model. These pertained to sleep latency, pre-operative anxiety, prevention of agitation and risk of breast cancer.ConclusionsThere is an abundance of reviews evaluating the effects of exogenous and endogenous MLT on health. In general, MLT has been shown to be associated with a wide variety of health outcomes in clinically and methodologically heterogeneous populations. Many reviews stressed the need for more high-quality randomised clinical trials to reduce the existing uncertainties

Multi-ancestry study of blood lipid levels identifies four loci interacting with physical activity.

Many genetic loci affect circulating lipid levels, but it remains unknown whether lifestyle factors, such as physical activity, modify these genetic effects. To identify lipid loci interacting with physical activity, we performed genome-wide analyses of circulating HDL cholesterol, LDL cholesterol, and triglyceride levels in up to 120,979 individuals of European, African, Asian, Hispanic, and Brazilian ancestry, with follow-up of suggestive associations in an additional 131,012 individuals. We find four loci, in/near CLASP1, LHX1, SNTA1, and CNTNAP2, that are associated with circulating lipid levels through interaction with physical activity; higher levels of physical activity enhance the HDL cholesterol-increasing effects of the CLASP1, LHX1, and SNTA1 loci and attenuate the LDL cholesterol-increasing effect of the CNTNAP2 locus. The CLASP1, LHX1, and SNTA1 regions harbor genes linked to muscle function and lipid metabolism. Our results elucidate the role of physical activity interactions in the genetic contribution to blood lipid levels

Self-Healing Collagen-Based Hydrogel for Brain Injury Therapy

Hydrogels derived from biopolymers, also called biohydrogels, have shown potential for brain injury therapy due to their tunable physical, chemical, and biological properties. Among different biohydrogels, those made from collagen type I are very promising candidates for the reparation of nervous tissues due to its biocompatibility, noncytotoxic properties, injectability, and self-healing ability. Moreover, although collagen does not naturally occur in the brain, it has been demonstrated that collagen type I, which resides in the basal lamina of the subventricular zone in adults, supports neural cell attachment, axonal growth, and cell proliferation due to its intrinsic content of specific cell-signaling domains. This chapter summarizes the most relevant results obtained from both in vitro and in vivo studies using self-healing biohydrogels based on collagen type I as key component in the field of neuroregeneration.University of RegensburgUniversidad de La LagunaMinisterio de Ciencia, Innovación y Universidade

Consistent patterns of common species across tropical tree communities

Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.Publisher PDFPeer reviewe