12 research outputs found
Comparison between the long-axis/in-plane and short-axis/out-of-plane approaches for ultrasound-guided vascular catheterization: an updated meta-analysis and trial sequential analysis
A global reference for human genetic variation
The 1000 Genomes Project set out to provide a comprehensive description of common human genetic variation by applying whole-genome sequencing to a diverse set of individuals from multiple populations. Here we report completion of the project, having reconstructed the genomes of 2,504 individuals from 26 populations using a combination of low-coverage whole-genome sequencing, deep exome sequencing, and dense microarray genotyping. We characterized a broad spectrum of genetic variation, in total over 88 million variants (84.7 million single nucleotide polymorphisms (SNPs), 3.6 million short insertions/deletions (indels), and 60,000 structural variants), all phased onto high-quality haplotypes. This resource includes >99% of SNP variants with a frequency of >1% for a variety of ancestries. We describe the distribution of genetic variation across the global sample, and discuss the implications for common disease studies
The environmental niche of the squid-jigging fleet in the North Pacific Ocean based on automatic identification system data
The vast number of fishing fleets and limited regulatory capacity pose challenges to the effective monitoring and management of marine fishery resources. To understand the fishing characteristics of spatial distribution for squid-jigging fleets in the North Pacific Ocean (NPO), satellite-based automatic identification system (AIS) data during 2016 ∼ 2020 and marine environmental data were applied to explore the drivers of fishing activities based on the boosted regression tree (BRT) and generalized additive model (GAM). The results showed that the BRT model has better performance than the GAM. The spatial distribution of squid-jigging fleets has a significant seasonality. Specifically, the spatial distribution of Fishing effort (FE) gradually shifted to the northwest from May to September, while gradually shifted to the southwest from October to November. The favourable area for focusing FE was the 150°E ∼ 165°E, 40°N ∼ 44°N. The latitudinal distribution of FE was not wide and the longitudinal distribution was long. Variations in the marine environment constantly influenced the FE of the squid-jigging fleets. Overall, the influence of sea surface temperature (T0) on FE was most significant. The favourable range of T0 for FE was 12 ∼ 20°C. Water temperature at the 300 m depth (T300) was also an important factor through the fishing season. The favourable range of T300 for FE was 3 ∼ 6°C. There were obvious differences in the influence of other environmental factors on FE in different months. Different environmental variables drive the spatial distribution of fishing effort in different months. This study may help to scientifically and effectively guide fishery management and sustainable development by evaluating the spatial variations in fishing activity
Tribological Properties of Tungsten Disulfide Nanoparticles Surface-Capped by Oleylamine and Maleic Anhydride Dodecyl Ester as Additive in Diisooctylsebacate
Oleylamine
(OM) and maleic anhydride dodecyl ester (MADE, synthesized
at our laboratory) were adopted as the surface modifiers to prepare
OM/MADE-capped tungsten disulfide (WS<sub>2</sub>) nanoparticles.
An X-ray diffractometer and a transmission electron microscope were
performed to analyze the microstructure and phase ingredients of the
OM/MADE-capped WS<sub>2</sub> nanoparticles. Moreover, a four-ball
friction and wear tester and a reciprocating tribometer were employed
to evaluate the tribological properties of the surface-capped WS<sub>2</sub> nanoparticles as the lubricant additive in diisooctylsebacate
(DIOS) from room temperature to 150 °C. The morphology of the
worn steel surfaces and wear scars and their chemical states were
investigated with a scanning electron microscope, three-dimensional
profilometry, and an X-ray photoelectron spectroscope. Results show
that OM-capped WS<sub>2</sub> nanoparticles nearly have no effect
on the tribological properties of the DIOS base oil. The OM/MADE-capped
WS<sub>2</sub> nanoparticles added in the same base stock at a concentration
of 2.0% (mass fraction), however, exhibit good dispersibility and
result in greatly improved tribological properties. The reason lies
in that, after surface-capping by MADE containing polar group and
OM containing coordination group, the OM/MADE-capped WS<sub>2</sub> particulates added in the base oil are well adsorbed on the sliding
surfaces of the steel–steel contact to afford a chemisorption
film with a low shear force. At the same time, OM/MADE-capped WS<sub>2</sub> nanoparticles as the additive in DIOS base oil take part
in tribochemical reactions to form tribofilm composed of WO<sub>3</sub> and iron oxides on sliding surfaces, which also contributes to reducing
the friction and wear of the steel sliding contact