1,164 research outputs found
Was the Ediacaran Shuram Excursion a globally synchronized early diagenetic event? Insights from methane-derived authigenic carbonates in the uppermost Doushantuo Formation, South China
The Ediacaran Period is characterized by the most profound negative carbon isotope (
Impact of Indoor Mobility Behavior on the Respiratory Infectious Diseases Transmission Trends
The importance of indoor human mobility in the transmission dynamics of
respiratory infectious diseases has been acknowledged. Previous studies have
predominantly addressed a single type of mobility behavior such as queueing and
a series of behaviors under specific scenarios. However, these studies ignore
the abstraction of mobility behavior in various scenes and the critical
examination of how these abstracted behaviors impact disease propagation. To
address these problems, this study considers people's mobility behaviors in a
general scenario, abstracting them into two main categories: crowding behavior,
related to the spatial aspect, and stopping behavior, related to the temporal
aspect. Accordingly, this study investigates their impacts on disease spreading
and the impact of individual spatio-temporal distribution resulting from these
mobility behaviors on epidemic transmission. First, a point of interest (POI)
method is introduced to quantify the crowding-related spatial POI factors
(i.e., the number of crowdings and the distance between crowdings) and
stopping-related temporal POI factors (i.e., the number of stoppings and the
duration of each stopping). Besides, a personal space determined with Voronoi
diagrams is used to construct the individual spatio-temporal distribution
factor. Second, two indicators (i.e., the daily number of new cases and the
average exposure risk of people) are applied to quantify epidemic transmission.
These indicators are derived from a fundamental model which accurately predicts
disease transmission between moving individuals. Third, a set of 200 indoor
scenarios is constructed and simulated to help determine variable values.
Concurrently, the influences and underlying mechanisms of these behavioral
factors on disease transmission are examined using structural equation modeling
and causal inference modeling.....
Glomerular C1q deposition and serum anti-C1q antibodies in anti-glomerular basement membrane disease
BACKGROUND: Anti-glomerular basement membrane (GBM) disease is a well-known antibody-induced autoimmune disease. A few patients have glomerular C1q deposition, but it is usually absent on renal histopathology. The role of C1q deposition in kidney injury is unclear. Recently, anti-C1q antibodies are demonstrated to be pathogenic in the target organ damage of many autoimmune diseases, by facilitating C1q deposition and enhancing complement activation via classical pathway. In the current study, we investigated the associations between anti-C1q antibodies in sera and C1q deposition in kidney of patients with anti-GBM disease. RESULTS: It was shown that the severity of kidney injury was comparable between patients with and without C1q deposition, including the prevalence of oliguria/auria, the median percentage of crescents in glomeruli and the mean concentration of serum creatinine. Serum anti-C1q antibodies were detected in 15/25 (60%) patients with a low titer. The prevalence of C1q deposition in kidney was comparable between patients with and without serum anti-C1q antibodies (26.7% vs. 30.0%, p > 0.05). No association was found between anti-C1q antibodies and the severity of kidney injury. CONCLUSIONS: The classical pathway of complement may not play a pathogenic role in the kidney injury of human anti-GBM disease. Anti-C1q antibodies could be detected in more than half of patients, which need further investigations
3D experimental study on a cylindrical floating breakwater system
The objective of the present study is to investigate the performance of a cylindrical floating breakwater system based on 3D experimental tests. The experiments were carried out in the wave basin (36 m*60 m*1.5 m)of the Ocean University of China. The cylindrical floating breakwater system consists of 10cylindrical floating breakwater units and 10mesh cages with balls in them, connected by 18 connectors and moored by a taut mooring system. The wave transmission coefficients, reflection coefficients, dissipation coefficients and motion responses of the floating breakwater are measured in both oblique and beam sea conditions. It is found that with the increase of the wavelength, both of the wave transmission coefficients and motion response amplitude of the FB system suffers an increase before it reaches its peak value, followed by a decrease trend. It can be concluded from the experiments that the proposed FB system has a satisfactory performance and it can be used to a wide range of sea conditions
Brominated Metabolites from the Marine Red Alga Laurencia similis
One new sesquiterpenoid, aristolan-1α-bromo-9β ,10β -epoxide (1), and one new indole alkaloid, 2,5-dibromo-N-methylindole (2), along with six sesquiterpenes and indoles were identified from the marine red alga Laurencia similis. Their structures were established on the basis of spectroscopic methods
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