Unraveling the hydrogeochemical characteristics and pollution sources of groundwater in an intensive industrial area, East China.

It is challenging to interpret hydrogeochemical datasets with complex natural and anthropogenic genesis in intensive industrial areas. This paper elucidates the hydrogeochemical characteristics and pollution sources of groundwater in an industrial park, East China, combining the self-organizing map (SOM), hydrochemical graphs, and correlation analysis. The results show that the total dissolved solids of groundwater range from 73.

Research progress in clinical trials of stem cell therapy for stroke and neurodegenerative diseases.

The incidence of stroke and neurodegenerative diseases is gradually increasing in modern society, but there is still no treatment that is effective enough. Stem cells are cells that can reproduce (self-renew) and differentiate into the body, which have shown significance in basic research, while doctors have also taken them into clinical trials to determine their efficacy and safety. Existing clinical trials mainly include middle-aged and elderly patients with stroke or Parkinson's disease (mostly 40-80 years old), mainly involving injection of mesenchymal stem cells and bone marrow mesenchymal stem cells through the veins and the putamen, with a dosage of mostly 10-10 cells.

The effects of ultrasonic vibration on riveting quality.

Ultrasonic vibration can reduce the forming force, decrease the friction in the metal forming process and improve the surface quality of the workpiece effectively. The effects of ultrasonic vibration on riveting quality were systematically studied by numerical simulation and experimental methods. The riveting force, interference, riveting head and microstructure of rivet under different vibration conditions were analyzed, in order to study the influence of the ultrasonic vibration on the riveting process.

Making Every Step Count: Minute-by-Minute Characterization of Step Counts Augments Remote Activity Monitoring in People With Multiple Sclerosis.

Background: Ambulatory disability is common in people with multiple sclerosis (MS). Remote monitoring using average daily step count (STEPS) can assess physical activity (activity) and disability in MS. STEPS correlates with conventional metrics such as the expanded disability status scale (Expanded Disability Status Scale; EDSS), Timed-25 Foot walk (T25FW) and timed up and go (TUG).

Multi-wavelength coherent random laser in bio-microfibers.

In this paper, pure silk protein was extracted from Bombyx mori silks and fabricated into a new kind of disordered bio-microfiber structure using electrospinning technology. Coherent random lasing emission with low threshold was achieved in the silk fibroin fibers. The random lasing emission wavelength can be tuned in the range of 33 nm by controlling the pump location with different scattering strengths.

Ultrasensitive all-fiber inline Fabry-Perot strain sensors for aerodynamic measurements in hypersonic flows.

This work proposes an ultrasensitive, temperature-insensitive, all-fiber inline Fabry-Perot (FP) strain sensor for aerodynamic coefficients measurements of a hypervelocity ballistic correlation model 2 in a Φ1 hypersonic wind tunnel. The FP sensors fabricated using 157 nm laser micromachining system are structurally simple, small-sized, and high-temperature resistance. 16 FP sensors are installed on a six-force balance, which is mounted inside the model, to sense the aerodynamic forces and moments of the model, and then the model's aerodynamic coefficients are calculated based on aerodynamic theory according to the test data.

Constitutive model of 6063 aluminum alloy under the ultrasonic vibration upsetting based on Johnson-Cook model.

Establishing an accurate constitutive relation in ultrasonic vibration assisted metal forming, can provides a reliable theoretical basis for analyzing the mechanism of the ultrasonic vibration on materials. A constitutive model of 6063 aluminum alloy under the ultrasonic vibration upsetting at room temperature was constructed based on Johnson-Cook Model and experimental results. The influence of amplitude and frequency on the yield strength, hardening coefficient and exponent were analyzed quantitatively.

Highly Integrated All-Fiber FP/FBG Sensor for Accurate Measurement of Strain under High Temperature.

Accurate measurement of strain is one of the most important issues for high temperature environments. We present a highly integrated all-fiber sensor to achieve precise measurements of strain/high-pressure, which consists of a fiber Bragg grating (FBG) inscribed by an 800 nm femtosecond laser cascaded with a micro extrinsic Fabry⁻Perot (FP) cavity fabricated by the 157 nm laser micromachining technique. FBG is sensitive to temperature, but insensitive to strain/pressure, whereas the FP is sensitive to strain/pressure, but has a small dependence on temperature.

A nanocrystalline-amorphous mixed layer obtained by ultrasonic shot peening on pure titanium at room temperature.

A nanocrystalline-amorphous (NC-A) mixed layer was obtained by ultrasonic shot peening (USP) on pure titanium at room temperature and observed by X-ray diffraction pattern (XRD), scanning electron microscope (SEM) and high-resolution transmission electron microscope (HRTEM). The results showed that the amorphization percentage in the NC-A mixed layer increased continuously with the increase of the peening duration, shot diameter and sonotrode amplitude or the decrease of the peening distance. The maximum amorphization percentage achieved in this study was 44.

Effects of ultrasonic vibration on the compression of pure titanium.

The technology of ultrasonic vibration assisted plastic forming possesses a great many merits, such as reducing the deformation resistance and friction, as well as improving the surface quality of parts. In this study, the ultrasonic vibration assisted compression tests were carried out on pure titanium in order to improve its formability. The results indicating that the ultrasonic vibration had no effort on elastic deformation, and the temperature of material only increased by 6 °C after compression with applying the ultrasonic vibration.