The effect of flooring on musculoskeletal symptoms in the lower extremities and low back among female nursing assistants

This study examines the effect of changing the floor from a 2-mm homogenous vinyl floor to a 4-mm heterogeneous vinyl floor (1.5-mm wear layer and 2.5-mm foam layer) on musculoskeletal symptoms in the lower extremities and low back among nursing assistants in a geriatric care centre. A pre-post design with a reference group consisting of nursing assistants from a similar geriatric care centre was used. Follow-up measurements were carried out 12 and 24 months after the intervention by means of questionnaires. At the 1-year follow-up, the pain intensity score in the feet of the intervention group had decreased compared with the baseline value and remained statistically significant at the 2-year follow-up. The decrease in pain intensity score of the feet in the intervention group was statistically significantly different from the reference group, both after 1 and 2 years. PRACTITIONER SUMMARY: The results show the importance of flooring in the workplace with regard to reducing musculoskeletal symptoms. Appropriate flooring is especially important in the female-dominated health care sector, where workers must stand or walk for long periods.     

Inhibition effect of a synthesized N, N＇-bis（2-hydroxybenzaldehyde）- 1, 3-propandiimine on corrosion of mild steel in HC1

The corrosion inhibition of mild steel in 1 mol/L HCl by N, N′-bis (2-hydroxybenzaldehyde)-1, 3-propandiimine (2-HBP) has been investigated by using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and chronoamperometry measurements. The experimental results suggest that this compound is an excellent corrosion inhibitor for mild steel and the inhibition efficiency increases with the increase in inhibitor concentration. Polarization curves reveal that this organic compound is a mixed type inhibitor. The effect of temperature on the corrosion behavior of mild steel with the addition of the Schiff base was studied in the temperature range from 25℃ to 65℃. The experimentally obtained adsorption isotherms follow the Langmuir equation. Activation and thermodynamic adsorption parameters such as E a , ΔH, ΔS, K ads and ΔG ads were calculated by the corrosion currents at different temperatures and using the adsorption isotherm. The morphology of mild steel surface in the absence and presence of 2-HBP was examined by atomic force microscope (AFM) images.     

Multivariate autoregressive feature extraction and the recognition of multichannel waveforms

It is proposed that the autoregressive coefficient matrices appearing in a multivariate autoregressive model fitting may be used for feature extraction purposes in problems concerning recognition of multichannel waveforms. It is demonstrated how the information contained in the autoregressive parameters may be further compressed by applying the ordinary or a modified Karhunen-Loeve expansion. The feature extraction procedures are illustrated on a large data base of seismic wave traces originating from shallow earthquakes and underground nuclear explosions. The results obtained (using a multivariate Gaussian classification algorithm) suggest that the combined autore-gressive/Karhunen-Loeve method has a considerably larger discrimination potential than the more conventional seismic discriminants.     

A Generalized Line and Junction Labeling Scheme with Application to scene Analysis

A line and junction labeling scheme is introduced that is valid for both planar and curved-surface bodies. Seven generalized junction types are defined and shown to cover all valid projections for a wide class of planar and curved-surface bodies. It is further shown that there are limitations on the permissible junction types as one moves from one end of a line segment to the other. The valid junction transitions provide 1) a new set of edge semantics for line labeling and 2) an ability to verify whether a given sequence of junctions forms a realizable configuration.     

In-situ comprehensive calibration of a tri-port nano-electro-mechanical device

We report on experiments performed in vacuum and at cryogenic temperatures on a tri-port nano-electro-mechanical (NEMS) device. One port is a very nonlinear capacitive actuation, while the two others implement the magnetomotive scheme with a linear input force port and a (quasi-linear) output velocity port. We present an experimental method enabling a full characterization of the nanomechanical device harmonic response: the nonlinear capacitance function C(x) is derived, and the normal parameters k and m (spring constant and mass) of the mode under study are measured through a careful definition of the motion (in meters) and of the applied forces (in Newtons). These results are obtained with a series of purely electric measurements performed without disconnecting/reconnecting the device, and rely only on known dc properties of the circuit, making use of a thermometric property of the oscillator itself: we use the Young modulus of the coating metal as a thermometer, and the resistivity for Joule heating. The setup requires only three connecting lines without any particular matching, enabling the preservation of a high impedance NEMS environment even at MHz frequencies. The experimental data are fit to a detailed electrical and thermal model of the NEMS device, demonstrating a complete understanding of its dynamics. These methods are quite general and can be adapted (as a whole, or in parts) to a large variety of electromechanical devices.     

Climate Change Action Alights on Satellite Detection of MethaneOA

<正>In an era of unwelcome broken records in climate change, 2021delivered yet another. According to figures released in January2022 by the US National Oceanic and Atmospheric Administration(NOAA)[1,2], the record for the annual net increase in atmospheric methane was broken for the second year in a row, hitting an estimated 17 parts per billion (ppb). The increase puts methane’s atmospheric concentration at 1909 ppb (Fig. 1), more than 2.5times its pre-industrial levels [3].     

分级FeCoNi磷化物的计量设计及其高效析氧性能（英文）

过渡金属磷化物是电催化设计中的新兴材料,而多元金属磷化物因其能显著提高电催化活性而备受关注.然而,由于不同种类金属前驱物之间水解和缩合速率的差异,当前有关超过两种金属元素和化学计量比精确控制的多元金属磷化物的报道非常少.因此,合理设计多元金属磷化物的组成对提高其催化性能具有重要意义.本工作通过直接磷化二价过渡金属离子氢氧化物的合成策略,制备了能够精确控制化学计量比(x:y:z=(1-10):(1-10):1)的分级结构Co_xNi_yFe_zP,其中具有最优组分的Co_1.3Ni_0.5Fe_0.2P在析氧反应(OER)中展示了优异的催化活性和高稳定性.密度泛函理论计算表明,相对于其他组分的过渡金属磷化物,Co_1.3Ni_0.5Fe_0.2P在费米能级附近的态密度明显增加,这可以增强催化剂对OH^-的吸附,从而提升OER性能.     

Effect of Carbon Properties on Melting Behavior of Mold Fluxes for Continuous Casting of Steels

Mold fluxes are synthetic slags used to coverthe liquid steel meniscus during continuous castingof steel.The flux,whichis continuously fed on thesurface of liquid pool during casting,melts first andthenflowsintothe gap between mold wall and solid-ified steel shell.It is well known that the perform-ance of the flux can greatly affect both the castingoperation and product quality.Because of its i mpor-tance,intensiveinvestigations have been performed,and considerable progress has been made[1-6].…     

用锯齿控制新经典撕裂模

新经典撕裂模(NTM)的开始取决于足够大的种子岛的存在。在欧洲联合环(JET)上证明，用长周期的锯齿能很容易地去稳NIMs，例如通过从离子回旋加热或电流驱动的锯齿致稳获得。这对于燃烧等离子体方案有着重要的意义，因为α粒子能强致稳锯齿。同样可以证明，通过刚好在反转半径外加热和电流驱动可去稳锯齿，这样在没有NIMs的情况下可获得较短的锯齿周期和较大的β值。