Ordovician geology and stratigraphy of China: A synthesis

China presently comprises several tectonic blocks and regions assembled over geological time and having independent histories. During the Ordovician, these blocks included South China, North China, Tarim, Qaidam, Junggar, Qiangtang-Qamdo, Lhasa and partially Himalaya, Sibumasu and Indochina, as well as the Altay-Xingâan and Songpan-Garze fold belts, which were discrete but adjacent. Twelve stratigraphic megaregions bounded by tectonic sutures or major fault zones are recognised for the Ordovician System. Some of them are further subdivided into regions according to specific lithological and biotic facies or distinct stratigraphic successions. The palaeontological features and biostratigraphic framework of these stratigraphic megaregions and regions are summarised. The unified biostratigraphic framework presented herein includes 33 graptolite and 27 conodont biozones through the Ordovician, together with supplementary biozones, communities or associations of brachiopods, trilobites, cephalopods, chitinozoans, acritarchs and radiolarians. With the constraints of integrative chronostratigraphy, biostratigraphy, chemostratigraphy, cyclostratigraphy and magnetostratigraphy, along with some geochronological data, our understanding of the temporal and spatial distribution of the Ordovician lithostratigraphic units on these major blocks has been significantly advanced. The refined integrative stratigraphic framework of the Ordovician provides a precise constraint on the major tectonic orogenies and biotic events evident in China

Enhanced durability of sulfonated poly (ether ether ketones)-based polymer electrolyte membranes by a multi-layer composite technology

Multi-layer composite membrane with low-cost and high durability is prepared via hot-spraying methods for proton exchange membrane fuel cell (PEMFC) applications, which consists of a mid layer of sulfonated poly (ether ether ketones) (SPEEK), two transition layers (TLs) and two PFSA outer layers (PLs). Here, PLs can protect SPEEK membrane against the chemical degradation from reactive oxygen species and endow the composite membrane with high chemical stability. TLs improve the interfacial compatibility between SPEEK membrane and PLs, avoiding the delamination problem. This multi-layer composite membrane exhibits a proper ion-exchange capacity (IEC) and higher proton conductivity compared with that of SPEEK membrane, and it also keeps a balance between water uptake and swelling ratio owing to the presence of the multi-layer structure. Besides, the lower cost of the composite membrane is confirmed due to the small content of Nafion. Single cell tests indicate that the multi-layer composite membrane has better cell performance than that of SPEEK membrane. The higher durability for the membrane under accelerated open circuit voltage (OCV) tests reveals the effectiveness of this multi-layer composite strategy in improving the chemical durability of the SPEEK membrane

Development of Cellulosic Paper-Based Test Strips for Mercury(II) Determination in Aqueous Solution

Titration method (dropping-on method) was introduced as an efficient approach for determining the mercury ion (Hg2+) concentration in aqueous solution by using fabricated cellulosic paper-based test strips. In this study, dithizone used as a recognition reagent was physically loaded on cellulosic paper-based test strips for Hg2+ selective recognition. The sensing mechanism was established on the spectral absorption rate of the coordination compound that was formed by dithizone and Hg2+ under strong acidic conditions. The calibration curve was obtained by the absorbency of Hg2+-dithizone complexes from different Hg2+ concentration solutions, and the correlation coefficient (R2) reached 0.9971. The detection range of the test trip for Hg2+ was obtained at 0.1 μg/mL to 30 μg/mL. Moreover, these superior cellulosic paper-based test strips have a rapid color-forming time (1.5 min) and low volume demand (3.7 μL samples at 0.0127 g/L dithizone recognition concentration). This portable paper-based test strip can give potential applications for field screening or on-site semiquantitative analysis

Core competencies among nurses engaged in pallative care: A scoping review

Aim: To synthesize available evidence about core competencies for nurses engaged in palliative care. Design: A scoping review conducted according to the framework from Joanna Briggs Institute. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist was adopted to report this scoping review. The PubMed, Web of Science, Embase, ScienceDriect, CNKI, WangFang, VIP and Sinomed databases were used to systematically search for published studies from their inception to December 2023. Two researchers independently screened and selected relevant studies and performed the data charting. Results: Twenty-six studies were included in this scoping review. Among these, 14 studies identified core competency assessment instruments among nurses engaged in palliative care, with the Palliative Care Core Competence Questionnaire was used most frequently; 13 studies investigated the status of core competencies of nurses engaged in palliative care, the majority of included studies indicated that nurse\u27s core competencies were at moderate levels; 11 studies explored the factors influencing the core competencies of the nurses engaged in palliative care, which were classified as sociodemographic-related factors, palliative care education-related factors, death attitude, palliative care practice-related experience and others. Conclusion: This scoping review offers a comprehensive overview of the current landscape of core competencies among nurses in palliative care. Findings suggested that the clinical nursing leaders need to develop tailored strategies and interventions to address specific factors and promote the continuous development of nurses\u27 competencies in palliative care. Relevance to Clinical Practice: Core competency assessment instruments equip nurses and healthcare organizations with a range of validated tools for evaluating their proficiency in palliative care. Targeted core competency enhancement programmes need to be developed to foster a nursing workforce better equipped to improve the quality of life of end-of-life patients and their families. Patient or Public Contribution: No patient or public contribution

Maternal Benzene Exposure during Pregnancy and Risk of Childhood Acute Lymphoblastic Leukemia: A Meta-Analysis of Epidemiologic Studies

<div><p>Background</p><p>The prevalence of childhood leukemia is increasing rapidly all over the world. However, studies on maternal benzene exposure during pregnancy and childhood acute lymphoblastic leukemia (ALL) have not been systematically assessed. Therefore, we performed a meta-analysis to investigate the association between maternal solvent, paint, petroleum exposure, and smoking during pregnancy and risk of childhood ALL.</p><p>Methods</p><p>Relevant studies up to September 1^st, 2013 were identified by searching the PubMed, EMBASE, Cochrane library and the Web of Science databases. The effects were pooled using either fixed or random effect models based on the heterogeneity of the studies.</p><p>Results</p><p>Twenty-eight case-control studies and one cohort study were included for analysis, with a total of 16,695 cases and 1,472,786 controls involved. Pooled odds ratio (OR) with 95% confidence interval (CI) for ALL was 1.25 (1.09, 1.45) for solvent, 1.23 (1.02, 1.47) for paint, 1.42 (1.10, 1.84) for petroleum exposure, and 0.99 (0.93, 1.06) for maternal smoking during pregnancy. No publication bias was found in this meta-analysis and consistent results were observed for subgroup and sensitivity analyses.</p><p>Conclusions</p><p>Childhood ALL was associated with maternal solvent, paint, and petroleum exposure during pregnancy. No association was found between ALL and maternal smoking during pregnancy. Avoidance of maternal occupational and environmental benzene exposure during pregnancy could contribute to a decrease in the risk of childhood ALL.</p></div

Photoredox catalysis for the fabrication of water-repellent surfaces with application for oil/water separation

Silanization processes with perfluoroalkyl silanes have been demonstrated to be effective in developing advanced materials with many functional properties, including hydrophobicity, water repellency, and self-cleaning properties. However, practical industrial applications of perfluoroalkyl silanes are limited by their extremely high cost. On the basis of our recent work on photoredox catalysis for amidation with perfluoroalkyl iodides, its application for surface chemical modification on filter paper, as an illustrative example, has been developed and evaluated. Before photocatalytic amidation, the surface is functionalized with amine functional groups by silanization with 3-(trimethoxysilyl)propylamine. All chemically modified surfaces have been fully characterized by attenuated total reflection infrared (ATR-IR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS), and three-dimensional (3D) profiling to confirm the successful silanization and photocatalytic amidation. After surface modification of the filter papers with perfluoroalkanamide, they show high water repellency and hydrophobicity with contact angles over 120°. These filter papers possess high wetting selectivity, which can be used to effectively separate the organic and aqueous biphasic mixtures. The perfluoroalkanamide-modified filter papers can be used for separating organic/aqueous biphasic mixtures over many cycles without lowering the separating efficiency, indicating their reusability and excellent durability

Summary of the results for childhood ALL in relation to maternal smoking during pregnancy: subgroup analyses.

<p>Abbreviations: OR, odds ratio.</p>a<p>Higgins’ <i>I²</i> statistic and 95%CI, are shown for a measure of the degree of heterogeneity across studies.</p>b<p><2000 means before the year of 2000, ≥2000 means after the year 2000.</p>c<p>Europe counties include Italy, France, Sweden, United Kingdom, Greece. Others include America, Canada, Australia, Israel, Brazil.</p>d<p>“high” means the score of quality range from 7 to 9, “moderate” means the score is among 4 to 6.</p><p>Summary of the results for childhood ALL in relation to maternal smoking during pregnancy: subgroup analyses.</p

Forest plot of the association between maternal exposure during pregnancy and risk of childhood ALL.

<p>The size of each box indicates the relative weight of each study in the meta-analysis; the bars show the 95% confidence intervals (CIs). For paint, the weights are from random effects analysis because there are heterogeneity among studies (<i>P</i><0.1).</p

Search Strategy for PubMed (up to September 1^st, 2013).

<p>Search Strategy for PubMed (up to September 1^st, 2013).</p

Characteristics of Studies on the Association Between Maternal Solvent, Paint, Petroleum Exposure During Pregnancy and Risk of ALL.

<p>Abbreviations: OR, odds ratio; RR, relative risk; HR, hazard ratio; CI, confidence interval; NOS, Newcastle-Ottawa-Scale; US, United States; USA,United States of America;UK, United Kingdom.</p><p>Characteristics of Studies on the Association Between Maternal Solvent, Paint, Petroleum Exposure During Pregnancy and Risk of ALL.</p