Considering the trend of aging societies, accompanying technology can help frail, elderly individuals participate in daily activities. The ideal accompanying robot should accompany the user in a ...proper position according to the activity scenarios and context; the prerequisite is that the accompanying robot should quickly move to a designated position and closely maintain it regardless of the direction in which the user moves. This paper proposes a user local coordinate-based strategy to satisfy this need. As a proof of concept, a novel “string-pot” approach was utilized to measure the position difference between the robot and the target. We implemented the control strategy and assessed its performance in our gait lab. The results showed that the robot can follow the user in the designated position while the user performs forward, backward, and lateral movements, turning, and walking along a curve.
Erythritol, having a nominal melting point of ∼118 °C, has been considered a candidate phase change material (PCM) for medium-temperature thermal energy storage (TES) due to its large latent heat of ...fusion (∼330 kJ/kg). However, it suffers from severe supercooling effect, up to several tens of degrees Celsius, upon crystallization by cooling, which remains to be a critical issue for its application. Here we propose a novel method of injection of gas bubbles into subcooled liquid erythritol to facilitate the nucleation of erythritol crystals, so as to reduce its degree of supercooling. Using this method, we obtained successfully an unprecedented reduction of the degree of supercooling of erythritol down to only 5 °C, which is much lower than those achieved by other conventional methods like adding a nucleating agent or ultrasonication. As a bonus, the latent heat of crystallization was found to be greatly increased by nearly 50%, from 218.2 kJ/kg to 322.3 kJ/kg. The injection of bubbles also enables an effective way for actively triggering the crystallization of erythritol in a controllable manner. Our results showed that by changing the injecting timing of bubbles, crystallization can always be triggered immediately with only the crystallization point being varied over a wide range. The injection of bubbles is thus deemed to be a highly-efficient, cost-effective, and scalable method for addressing the supercooling issue of erythritol, and other similar PCMs with deep supercooling, making it more promising for TES applications.
•We propose a new method by injection of bubbles to reduce supercooling of erythritol.•The degree of supercooling can be decreased down to only 5 °C, a record-low value.•The latent heat of crystallization of erythritol is increased by nearly 50% as a bonus.•This method also enables an effective way for controllable triggering of crystallization.
Abstract
How was Chinese people’s confidence in the political system linked to their perception of Covid infection risk, perception of health threat of Covid infection, lockdown experience, and ...attitudes toward the dynamic Zero-Covid policy? Using 2 waves of online surveys conducted in 2020 and 2022, we investigated how these factors were related. Individuals who were more supportive of the Zero-Covid policy were more confident. Those who were less supportive of the Zero-Covid policy were from areas with more severe Covid infections and experienced a longer lockdown as well; these individuals also perceived higher Covid infection risk and health threat. As such, their confidence in the political system was also more likely to drop from 2020 to 2022. In sum, these findings suggest that Chinese people’s confidence in the political system was linked to their Covid infection risk perception, perceived Covid threat to health, lockdown experience, and attitudes toward the Zero-Covid policy. These findings were corroborated with the severity of Covid infections in the province and individual’s political beliefs and orientation.
Intimate partner violence (IPV) and HIV are highly prevalent worldwide among MSM. However, the association between IPV and HIV seroconversion is virtually unknown. This 12-month prospective cohort ...study was conducted among MSM in Shenyang, China to explore the causality between IPV and the incidence of HIV. Adjusted Hazard Ratios (aHRs) of HIV acquisition were derived from a multivariate time-dependent Cox model and applied to calculate population attributable fractions (PAFs). Among 476 HIV-negative MSM subjects, 89(18.7%) reported being victims of IPV in the past 3 months (P3M). IPV was significantly correlated with lower education, having more condomless anal intercourse (CAI) and being depressed (each P < 0.05). The incidence of HIV among IPV victims was 11.3/100 PY compared to 3.8/100 PY in non-IPV-victims. Furthermore, IPV victimization was independently associated with HIV seroconversion (aHR = 4.1, PAF = 37.9%). Other predictors for seroconversion included non-local residence in Liaoning province (aHR = 3.9, PAF = 45.2%), engaging in condomless receptive anal intercourse (CRAI)(aHR = 3.1, PAF = 24.2%) or CAI with casual male partners (aHR = 3.8, PAF = 26.3%) in the P3M and syphilis infection (aHR = 4.7, PAF = 33.7%) (each P < 0.05). IPV increased the HIV seroconversion risk of MSM, with a high PAF. HIV prevention programs should integrate IPV screening and intervention, and MSM affected by IPV need to be preferentially enrolled in pre-exposure prophylaxis.
This letter proposes a new concept of a compact multidirection-beam antenna-in-package (AiP) for mobile devices. The AiP is the first integration of three vertically polarized millimeter-wave endfire ...horn antennas and a broadside horn antenna on a single substrate to cover four directions. The antennas are able to connect to radio frequency integrated circuits (RFICs) situated in the cavity at the backside of the substrate using bond wires. The size of the fabricated AiP is 6 mm × 6 mm × 1.5 mm (=1.2λ 0 × 1.2λ 0 × 0.3λ 0 ) including 0.3 mm thickness of RFICs. The impedance bandwidth (|S 11 | <; -15 dB) fully covers the 60 GHz band (57-66 GHz). The measured boresight gain of the endfire antenna and the broadside antenna is 5 dBi at 57 GHz and 6.3 dBi at 60 GHz, respectively.
Methylating drugs such as temozolomide (TMZ) are widely used in the treatment of brain tumors including malignant glioblastoma. The mechanism of TMZ-induced glioblastoma cell death and apoptosis, ...however, is not fully understood. Here, we tested the potential involvement of AMP-activated protein kinase (AMPK) in this process. We found that methylating agents TMZ and N-methyl-N′-nitro-N-nitrosoguanidine induce AMPK activation in primary cultured human glioblastoma and glioblastoma cell lines. TMZ-induced O6-methylguanine production is involved in AMPK activation. O6-benzylguanine, an O6-methylguanine-DNA methyltransferase inhibitor, enhances TMZ-induced O6-methylguanine production, leading to enhanced reactive oxygen species production, which serves as an upstream signal for AMPK activation. Activation of AMPK is involved in TMZ-induced glioblastoma cell death and apoptosis. AMPK inhibitor (Compound C) or AMPKα siRNA knockdown inhibits TMZ-induced glioblastoma cell death and apoptosis, whereas AMPK activator 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside enhances it. In further studies, we found that activation of AMPK is involved in TMZ-induced p53 activation and subsequent p21, Noxa, and Bax up-regulation. Activation of AMPK by TMZ also inhibits mTOR complex 1 (mTORC1) signaling and promotes anti-apoptosis protein Bcl-2 down-regulation, which together mediate TMZ-induced pro-cell apoptosis effects. Our study suggests that activation of AMPK by TMZ contributes to glioblastoma cell apoptosis, probably by promoting p53 activation and inhibiting mTORC1 signaling.
Purpose
The purpose of this paper is to construct the algebraic traveling wave solutions of the (3 + 1)-dimensional modified KdV-Zakharov-Kuznetsve (KdV-Z-K) equation, which can be usually used to ...express shallow water wave phenomena.
Design/methodology/approach
The authors apply the planar dynamical systems and invariant algebraic cure approach to find the algebraic traveling wave solutions and rational solutions of the (3 + 1)-dimensional modified KdV-Z-K equation. Also, the planar dynamical systems and invariant algebraic cure approach is applied to considered equation for finding algebraic traveling wave solutions.
Findings
As a result, the authors can find that the integral constant is zero and non-zero, the algebraic traveling wave solutions have different evolutionary processes. These results help to better reveal the evolutionary mechanism of shallow water wave phenomena and find internal connections.
Research limitations/implications
The paper presents that the implemented methods as a powerful mathematical tool deal with (3 + 1)-dimensional modified KdV-Z-K equation by using the planar dynamical systems and invariant algebraic cure.
Practical implications
By considering important characteristics of algebraic traveling wave solutions, one can understand the evolutionary mechanism of shallow water wave phenomena and find internal connections.
Originality/value
To the best of the authors’ knowledge, the algebraic traveling wave solutions have not been reported in other places. Finally, the algebraic traveling wave solutions nonlinear dynamics behavior was shown.
The sympathetic nervous system-catecholamine-uncoupling protein 1 (UCP1) axis plays an essential role in non-shivering adaptive thermogenesis. However, whether there exists a direct effector that ...physically connects catecholamine signalling to UCP1 in response to acute cold is unknown. Here we report that outer mitochondrial membrane-located AIDA is phosphorylated at S161 by the catecholamine-activated protein kinase A (PKA). Phosphorylated AIDA translocates to the intermembrane space, where it binds to and activates the uncoupling activity of UCP1 by promoting cysteine oxidation of UCP1. Adipocyte-specific depletion of AIDA abrogates UCP1-dependent thermogenesis, resulting in hypothermia during acute cold exposure. Re-expression of S161A-AIDA, unlike wild-type AIDA, fails to restore the acute cold response in Aida-knockout mice. The PKA-AIDA-UCP1 axis is highly conserved in mammals, including hibernators. Denervation of the sympathetic postganglionic fibres abolishes cold-induced AIDA-dependent thermogenesis. These findings uncover a direct mechanistic link between sympathetic input and UCP1-mediated adaptive thermogenesis.
The effects of general anesthetics on the developing brain have aroused much attention in recent years. Sevoflurane, a commonly used inhalation anesthetic especially in pediatric anesthesia, can ...induce developmental neurotoxicity. In this study, the differentially expressed mRNAs in the hippocampus of newborn rats exposed to 3% sevoflurane for 6 h were detected by RNA-Sequencing. Those data indicated that the mRNA of Klotho was increased after exposure to sevoflurane. Moreover, the protein expression of Klotho was assayed by Western Blot. Besides over-expression and under-expression of Klotho protein, we also detected changes of cell proliferation, ROS, JC-1, and Bcl-2/Bax ratio in PC12 cells exposed to sevoflurane. After exposure to 3% sevoflurane, the expression of Klotho protein increased in the hippocampus of neonatal rats. In PC12 cells, exposure to sevoflurane could increase cellular ROS level, reduce mitochondrial membrane potential and Bcl-2/Bax ratio. While overexpression of Klotho alleviated the above changes, knockdown of Klotho aggravated the injury of sevoflurane. Klotho protein could reduce oxidative stress and mitochondrial injury induced by sevoflurane in the neuron.
There is evidence that warming leads to greater evapotranspiration and surface drying, thus contributing to increasing intensity and duration of drought and implying that mitigation would reduce ...water stresses. However, understanding the overall impact of climate change mitigation on water resources requires accounting for the second part of the equation, i.e., the impact of mitigation-induced changes in water demands from human activities. By using integrated, high-resolution models of human and natural system processes to understand potential synergies and/or constraints within the climate–energy–water nexus, we show that in the United States, over the course of the 21st century and under one set of consistent socioeconomics, the reductions in water stress from slower rates of climate change resulting from emission mitigation are overwhelmed by the increased water stress from the emissions mitigation itself. The finding that the human dimension outpaces the benefits from mitigating climate change is contradictory to the general perception that climate change mitigation improves water conditions. This research shows the potential for unintended and negative consequences of climate change mitigation.
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