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For the 5-DoF gimballing magnetically suspended flywheel (MSFW), a three-degrees-of-freedom (DoF) active magnetic bearing (AMB) with a conical gap is used as an electromagnetic actuator to suspend the flywheel (FW) rotor, so the gyro moment of gimballing MSFW is improved by actively deflecting FW rotor with the conical AMB. Firstly, the dynamic models of the FW rotor with the 3-DoF conical AMB are investigated, and the magnetic forces using the equivalent magnetic circuit and the FEM model are analyzed. Moreover, the coupling effect among three controllable DoFs of conical AMB is investigated when the position of the FW rotor sets at different values. Furthermore, the negative torques of conical AMB are studied when the FW rotor is stably suspended at the equilibrium position. The experimental results indicate that the controllable deflection angle of 3-DoF conical AMB reaches 1°, the coupling ratio among three controllable DoFs is reduced to 9%, and the negative torque during the active deflecting process is 0.02 Nm. Compared to the normal AMB with the planar gap, the designed 3-DoF conical AMB has a wide deflection angle, minor coupling effect, and tiny negative torque. Therefore, the 3-DoF conical AMB causes slight influences on the FW rotor during the suspension and deflection control of gimballing MSFW, and it is more suitable for the gimballing MSFW. [ABSTRACT FROM AUTHOR]

Focusing on the network congestion and packet loss in the networked systems, a recursive quantization-based event triggered observer (RQETO) is proposed in this paper. The RQETO is composed of the local observer and the remote observer. The local observer reduces the amount of transmitted measured output by incorporating the event triggered strategy with the improved quantization mechanism. The improved quantization mechanism is based on the recursive algorithm, which can constrain the quantization error within the maximum allowable quantization error. The remote observer compensates the impact of packet loss by Bernoulli distribution model and hold-input strategy after receiving the data transmitted by the local observer. Through the local observer and the remote observer, network congestion is adequately alleviated, and the impact of packet loss is compensated while obtaining the accurate state estimation. The stability of the RQETO is proved by Lyapunov method, and the effectiveness of the RQETO is demonstrated on brushless direct current motor and Net-Con PC104 experimental platform. [ABSTRACT FROM AUTHOR]

The synchronous disturbance acting on the magnetically suspended momentum wheel (MSMW) would affect its suspension stability and control accuracy, so a varied-gain compound model is proposed to attenuate the synchronous disturbances of the MSMW with varying rotating frequencies. The disturbance frequency is varying with the rotating frequency of the MSMW, the gain and frequency of the disturbance observer are regulated to maintain the asymptotic stability, and the feedback gain of the state feedback is scheduled to avoid the complex repeated acquisition of control parameters. Finally, the numerical simulations and experiments are performed to validate the effectiveness of the proposed varied-gain control model. The results indicate that the proposed control model could effectively attenuate the synchronous disturbances and maintain the asymptotic stability of the MSMW when the rotating speed changes. [ABSTRACT FROM AUTHOR]

This paper concentrates on network congestion and security issue for networked control systems under the hybrid attacks. The hybrid attacks including deception attack, replay attack and denial‐of‐service attack are modelled as Bernoulli random process. A general form adaptive event‐triggered scheme (AETS) under the hybrid attacks is designed to alleviate the network congestion and save communication resources utilizing adaptive threshold and the weighted average of data packets. Meanwhile, the security issue under the hybrid attacks is addressed by a dynamic output feedback controller (DOFC) based on the AETS. Moreover, the sufficient conditions are obtained by a piecewise Lyapunov function to guarantee that the closed‐loop system is exponentially mean‐square stable. A practical experiment on networked motor control system verifies the effectiveness of the proposed scheme. The proposed scheme can not only save communication resources to further alleviate network congestion, but also defense the hybrid attacks in the network. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic and interventions addressing it raise important questions about human mobility that have geopolitical implications. This forum uses mobility and immobility during the pandemic as lenses onto the ways that routinised state power reacts to acute uncertainties, as well as how these reactions impact politics and societies. Specifically, we propose the concept of "shock mobility" as migratory routines radically reconfigured: emergency flights from epicentres, mass repatriations, lockdowns, quarantines. Patterns of shock mobility and immobility are not new categories of movement, but rather are significant alterations to the timing, duration, intensity, and relations among existing movements. Many of these alterations have been induced by governments' reactions to the pandemic in both migrant-sending and receiving contexts, which can be especially consequential for migrants in and from the Global South. Our interventions explore these processes by highlighting experiences of Afghans and Kurds along Iran's borders, Western Africans in Europe, Filipino workers, irregular Bangladeshis in Qatar, Central Americans travelling northwards via Mexico, and rural-urban migrants in India. In total, we argue that tracing shocks' dynamics in a comparative manner provides an analytical means for assessing the long-term implications of the pandemic, building theories about how and why any particular post-crisis world emerges as it does, and paving the way for future empirical work. [ABSTRACT FROM AUTHOR]

The Chinese government's response to the COVID-19 pandemic can be broken into three stages – from denial in early 2020, to relatively successful management from March 2020 to March 2022, and finally to the disastrous zero-COVID policy from March until November 2022. The article traces this to a general trend in China since the 2010s, namely the state's increasing concentration of "logistical power" (state and non-state actors' capacity to generate social dynamics based on the coordination of mobility), which led to "logistical violence" (force that destroys social dynamics based on the state's exclusive control over mobility). Informed by Hannah Arendt's thought and based on my engagement in public discussion in China during and after COVID pandemic, I propose the concepts of "logistical power" and "logistical violence" in order to facilitate public reflections – in addition to providing academic explanations – about what the pandemic may mean for China's future. [ABSTRACT FROM AUTHOR]

Perfluorooctanoic acid is ubiquitous in water bodies and is detrimental to the health of organisms. Effectively removing perfluorooctanoic acid (PFOA), a persistent organic pollutant, has been a hot topic around the world. With traditional physical, chemical, and biological methods, it is difficult to effectively and completely remove PFOA, the costs are high, and it is easy to cause secondary pollution. There are difficulties in applying some technologies. Therefore, more efficient and green degradation technologies have been sought. Photochemical degradation has been shown to be a low-cost, efficient, and sustainable technique for PFOA removal from water. Photocatalytic degradation technology offers great potential and prospects for the efficient degradation of PFOA. Most studies on PFOA have been conducted under ideal laboratory conditions at concentrations that are higher than those detected in real wastewater. This paper summarizes the research status of the photo-oxidative degradation of PFOA, and it summarizes the mechanism and kinetics of PFOA degradation in different systems, as well as the influence of key factors on the photo-oxidative degradation and defluoridation process, such as system pH, photocatalyst concentration, etc. PFOA photodegradation technology's existing problems and future work directions are also presented. This review provides a useful reference for future research on PFOA pollution control technology. [ABSTRACT FROM AUTHOR]

This paper focuses on network time delay, network congestion, and network security in the networked control system. A secure event-based quantized networked control system (SEQNCS) is proposed to address these problems. The predictive method in the SEQNCS actively compensates time delay both in the forward channel and feedback channel according to the previous states and control inputs. Both the event-driven strategy and quantizer are introduced into the SEQNCS to alleviate network congestion by the event trigger conditions and quantization density. The encrypted encoding quantizer is constructed in the SEQNCS to implement the protection of data security under deception attacks while quantifying the transmitted data. The proposed SEQNCS achieves desired system performance of the networked control system under time delay and deception attacks while alleviating network congestion. The stability of the SEQNCS is proved by the piecewise linear model approach. Practical experiments are implemented to demonstrate the effectiveness of the proposed SEQNCS. [ABSTRACT FROM AUTHOR]

[Objective] Drought is the most important abiotic stress facing agricultural management and economic development in many regions and countries. The aim of this paper is to identify the spatiotemporal variation of drought in Yunnan Province, using the standardized precipitation index (SPI). [Method] Meteorological data measured over the past 31 years from 36 meteorological stations across the province were used in the analysis. Multi-scale variations of the droughts in both time and space were calculated using SPI, GIS, nonparametric Mann-Kendall trend test and other methods. [Result] ①Both annual and seasonal SPI fluctuated temporally, but we identified a small annual increase in spring SPI, small annual decreases in summer, autumn and winter SPI. The autumn SPI varied mostly, and the winter SPI least. The annual SPI varied from -1.95 to 1.44. ②The annual drought frequency varied from 32.26% to 50.00%, with the severity of most droughts varying from mild to extreme range. Spatially, drought occurred more frequently in Wenshan, Honghe, Kunming, Chuxiong and Dehong than in other regions in the province. ③Seasonally, drought frequency in spring, summer, autumn and winter was 39.86%, 39.83%, 38.43%, and 41.33%, respectively. Although drought frequency in different seasons was close, their severity differed considerably. ④Annually, except for five meteorological stations which found increased drought frequency, drought frequency in other stations remained statistically the same. Seasonally, most stations showed decreased drought frequency in spring, eleven stations showed increased drought frequency in summer, and six and two stations showed increased autumn droughts and winter droughts, respectively. [Conclusion] Annual and seasonal drought frequency is spatially heterogeneous across the province. Droughts in the province are seasonal, with droughts occurring in spring and winter more frequently and severely. [ABSTRACT FROM AUTHOR]

The vibration performance is critical to the suspension control and the torque precision of the magnetically suspended momentum flywheel (MSMW). The translational and torsional vibration of the MSMW are investigated in this article, and the damping regulation method is proposed to improve the anti-vibration performance of the MSMW. Firstly, the modellings of the MSMW, including the dynamic models and the displacement coordinate, are developed, and the comprehensive damping characteristics of the MSMW are investigated. Moreover, the transfer functions of the translational and the torsional vibrations are established using the dimensionless model, and the relationship between the dynamic response and the stiffness/damping coefficient is studied. Furthermore, the numerical simulations of the dynamic response of the translational and torsional vibration are conducted. Finally, the experiments are designed to verify the vibration characteristics of the MSMW, and the dynamic displacements are measured to analyze the anti-vibration performance of the proposed damping regulation method. The results indicate that the displacement deflection of the translational vibration is reduced by 68.8%, and the angle deflection of the torsional vibration is mitigated by 71.2% by regulating the damping coefficient. [ABSTRACT FROM AUTHOR]

As the current excessive accumulation of fluoride (F−) in the environment can be hazardous to human health, it is essential to remove fluoride from wastewater. In this study, diatomite (DA) was used as a raw material and modified using aluminum hydroxide (Al-DA) for use in the adsorption of F− from water bodies. SEM, EDS, XRD, FTIR, and Zeta potential characterization analyses were carried out; adsorption tests and kinetic fitting were performed, and the effects of pH, dosing quantity, and presence of interfering ions on the adsorption of F− by the materials were investigated. The results show that the Freundlich model effectively describes the adsorption process of F− on DA, which therefore involves adsorption-complexation interactions; however, the Langmuir model effectively describes the adsorption process of F− on Al-DA, corresponding to unimolecular layer adsorption mainly via ion-exchange interactions, that is, adsorption is dominated by chemisorption. Aluminum hydroxide was shown to be the main species involved in F− adsorption. The efficiency of F− removal by DA and Al-DA was over 91% and 97% for 2 h, and the adsorption kinetics were effectively fit by the quasi-secondary model, suggesting that chemical interactions between the absorbents and F− control the adsorption process. The adsorption of F− was highly dependent on the pH of the system, and the maximum adsorption performance was obtained at pH 6 and 4. The optimal dosage of DA and Al-DA was 4 g/L. Even in the presence of interfering ions, the removal of F− on Al-DA reached 89%, showing good selectivity. XRD and FTIR studies showed that the mechanism of F− adsorption on Al-DA involved ion exchange and the formation of F–Al bonds. [ABSTRACT FROM AUTHOR]

The Left is under siege across the globe. Anti-NATO arguments are ridiculed as pro-Putin. The US military-industry nexus is rapidly extending to become a global military-industry-finance-media nexus. The Left in China, India, Turkey, Brazil and many other countries have been crushed or became complicit with authoritarianism. In Europe, progressive ideals that have enjoyed wide support since the end of World War Two are being seriously challenged. In this conversation, Ranabir Samaddar from India and Biao Xiang from China reflect on the shortcomings of the Western Left in their response to the Russia-Ukraine war, and argue that the international Left must take viewpoints from the Global South much more seriously. [ABSTRACT FROM AUTHOR]

In this paper, a periodic signal suppression method in position domain based on repetitive control (RC) is proposed to realize high-precision speed control for the gimbal servo system of the single gimbal control moment gyro (SGCMG). To reduce the volume and weight while outputting large torque, the gimbal servo system usually needs to install the harmonic drive. However, the nonlinear transmission characteristics of the harmonic drive are also introduced into the gimbal servo system and make the speed fluctuate. Considering the speed fluctuation signal shown as a fixed frequency in the position domain, a position domain RC method combined with acceleration feedback is designed to realize the speed fluctuation minimization. The position domain RC improves the dynamic characteristics, while the acceleration feedback increases the damping of the system. To analyze the stability, the position domain RC is converted into the time domain through the domain transformation method, and a phase compensator is designed to improve the stability and increase the bandwidth of the position domain RC by compensating for the phase lag of the middle and low frequency, respectively. The feasibility and effectiveness of the proposed method are verified by the simulation and experimental results. These results illustrate that after applying the proposed approach, the output speed fluctuation and harmonic components decrease more than 20% and 24.1%, respectively. [ABSTRACT FROM AUTHOR]

In the article the author offers a relational interpretation of global governance since the 1960s. Topics include the reimagination of Western civilization through modernization via capitalism, findings and claims by anthropologists and other skeptics that challenged the universal formula of market-based development, and turning point in the worldwiew of elites gathered at the 2007 World Economic Forum. Also included are commentaries on the article.

Background: Small cell lung cancer (SCLC) is the most malignant and common form of neuroendocrine lung cancer with pure (P‐SCLC) and combined subtypes (C‐SCLC). However, little is known about the differences between these two groups and in this study we aimed to provide a more comprehensive insight into SCLC. Methods: Data from 580 postoperative patients with pathologically confirmed SCLC in Shanghai Chest Hospital from January 2010 to December 2020 were collected retrospectively. The clinical characteristics and prognosis were analyzed. Results: A total of 357 P‐SCLC patients and 223 C‐SCLC patients were included. The results indicated that P‐SCLC appeared to have a higher proportion of being located in the middle lobe than C‐SCLC. The incidences of P‐SCLC in patients with visceral pleural invasion (VPI) and in stage II were higher than C‐SCLC, while C‐SCLC was more likely to be accompanied by higher incidences of epidermal growth factor receptor (EGFR) mutation, anaplastic lymphoma kinase (ALK) rearrangement, and higher levels of CEA, SCCA and CYFRA21‐1 than P‐SCLC. The most common were SCLC combined with large cell neuroendocrine components among 223 C‐SCLCs. Survival analysis confirmed a more favorable disease‐free survival (DFS) (p = 0.016) and overall survival (OS) (p = 0.024) in patients with P‐SCLCs compared with C‐SCLCs. Histological type, tumor location, pN stage, adjuvant chemotherapy, serum NSE and CA125 levels were independent risk factors for survival rate in SCLC. In addition, adjuvant chemotherapy was beneficial in improving stage I P‐SCLC and C‐SCLC DFS and OS rates, and similar results were not seen in adjuvant radiation therapy. Conclusions: Patients with C‐SCLC have a poorer prognosis than P‐SCLC patients. We determined that large cell neuroendocrine carcinoma was the most common additional component of C‐SCLC, and patients with this component appeared to have a longer DFS and OS than other combined components. [ABSTRACT FROM AUTHOR]

Objective: Multiple sclerosis (MS) is a common demyelinating central nervous system disease. MRI methods that can quantify myelin loss are needed for trials of putative remyelinating agents. Quantitative magnetization transfer MRI introduced the macromolecule proton fraction (MPF), which correlates with myelin concentration. We developed an alternative approach, Simultaneous‐Multi‐Angular‐Relaxometry‐of‐Tissue (SMART) MRI, to generate MPF. Our objective was to test SMART‐derived MPF metric as a potential imaging biomarker of demyelination. Methods: Twenty healthy control (HC), 11 relapsing–remitting MS (RRMS), 22 progressive MS (PMS), and one subject with a biopsied tumefactive demyelinating lesion were scanned at 3T using SMART MRI. SMART‐derived MPF metric was determined in normal‐appearing cortical gray matter (NAGM), normal‐appearing subcortical white matter (NAWM), and demyelinating lesions. MPF metric was evaluated for correlations with physical and cognitive test scores. Comparisons were made between HC and MS and between MS subtypes. Furthermore, correlations were determined between MPF and neuropathology in the biopsied person. Results: SMART‐derived MPF in NAGM and NAWM were lower in MS than HC (p < 0.001). MPF in NAGM, NAWM and lesions differentiated RRMS from PMS (p < 0.01, p < 0.001, p < 0.001, respectively), whereas lesion volumes did not. MPF in NAGM, NAWM and lesions correlated with the Expanded Disability Status Scale (p < 0.01, p < 0.001, p < 0.001, respectively) and nine‐hole peg test (p < 0.001, p < 0.001, p < 0.01, respectively). MPF was lower in the histopathologically confirmed inflammatory demyelinating lesion than the contralateral NAWM and increased in the biopsied lesion over time, mirroring improved clinical performance. Interpretation: SMART‐derived MPF metric holds potential as a quantitative imaging biomarker of demyelination and remyelination. [ABSTRACT FROM AUTHOR]

Background: Imaging biomarkers of progressive multiple sclerosis (MS) are needed. Quantitative gradient recalled echo (qGRE) magnetic resonance imaging (MRI) evaluates microstructural tissue damage in MS. Objective: To evaluate qGRE-derived R2t* as an imaging biomarker of MS progression compared with atrophy and lesion burden. Methods: Twenty-three non-relapsing progressive MS (PMS), 22 relapsing-remitting MS (RRMS), and 18 healthy control participants underwent standard MS physical and cognitive neurological assessments and imaging with qGRE, FLAIR, and MPRAGE at 3T. PMS subjects were tested clinically and imaged every 9 months over 45 months. Imaging measures included lesion burden, atrophy, and R2t* in cortical gray matter (GM), deep GM, and normal-appearing white matter (NAWM). Longitudinal analysis of clinical performance and imaging biomarkers in PMS subjects was conducted via linear models with subject as repeated, within-subject factor. Relationship between imaging biomarkers and clinical scores was assessed by Spearman rank correlation. Results: R2t* reductions correlated with neurological impairment cross-sectionally and longitudinally. PMS patients with clinically defined disease progression (N = 13) showed faster decrease of R2t* in NAWM and deep GM compared with the clinically stable PMS group (N = 10). Importantly, tissue damage measured by R2t* outperformed lesion burden and atrophy as a biomarker of progression during the study period. Conclusion: qGRE-derived R2t* is a potential imaging biomarker of MS progression. [ABSTRACT FROM AUTHOR]

Recently, identifying the contamination status and assessing the health risk of per- and polyfluoroalkyl substances (PFASs) in surface water and groundwater have been of great significance. Eighteen individual PFASs were analyzed in thirty-three surface/groundwater samples during one period in a fluorine chemical park (Park A) and during two periods in Park B. The mean total concentration of 18 PFASs (∑PFASs) in Park A (9104.63 ng·L−1) was significantly higher than that in the wet season (WS) (801.68 ng·L−1) or DS (714.64 ng·L−1) in Park B. The perfluorobutane sulfonate (PFBS) was the predominant substance in the two parks, and the maximum concentration in groundwater exceeded 10,000 ng·L−1. The contamination status in the wet season (WS) was higher than that in the dry season (DS) in Park B. The ∑PFASs in Park A presented an increasing tendency following the groundwater flow direction, whereas this rule was limited to all periods in Park B. Two relative source contributions (RSCs) of 20% or 100% allowed assessing the PFASs risk to different age groups, and the results revealed that some PFASs (4 ≤ C ≤ 7 or 9 ≤ C ≤ 12) were identified as having a low risk quotient (RQ), except for perfluorooctane sulfonate (PFOS) and PFOA (C = 8). The RQmix value mainly relies on PFOA and PFOS, with a larger contribution rate of 80–90%. All assessed cases (case 1, case 2, case 3, and case 4) in all age groups revealed that infants were vulnerable to PFASs influence, followed by children, teenagers, and adults. [ABSTRACT FROM AUTHOR]

An air-blower with active magnetic bearings could improve working efficiency and reduce energy consumption by avoiding contact between the rotor shaft and the stator part. The structure and prototype of a magnetically suspended air-blower are herein introduced, and the force models of active magnetic bearings developed. Furthermore, the dynamic models of a rotor shaft with unbalance terms were established to investigate the vibration characteristics of the magnetically suspended air-blower. The vibration characteristics of the rotor shaft with unbalance terms were analyzed, and the complex-field cross-feedback control was designed to suppress the vibration amplitude. Finally, experiments were conducted to verify the theoretical models, and the results indicated that the vibration amplitude of the rotor shaft with unbalance terms could be intensified by the rotating frequency, and the nutation vibration was reduced by 50% through increasing the high-frequency nutation coefficient of the complex-field cross-feedback control model. The results indicated that the vibration analysis of the rotor shaft was meaningful to the design and control of the magnetically suspended air-blower. [ABSTRACT FROM AUTHOR]

The control performance of magnetically suspended motor with heavy self-weight and great moment of inertia is affected by parameter uncertainty and external disturbances, and the coupling effect in radial tilting of magnetically suspended motor becomes serious with the increase of rotational speed and moment of inertia, and then, the robustness would be reduced. Therefore, an internal model control model is proposed to adjust the robustness of magnetically suspended motor. Based on the internal model control model, a decoupling internal model control model is designed for magnetically suspended motor on four degrees of freedom. Simulation and experiment are conducted to verify that the internal model control model improves the robust stability of magnetically suspended motor, and the decoupling internal model control model effectively realizes the decoupling control of magnetically suspended motor on four degrees of freedom. [ABSTRACT FROM AUTHOR]

This paper addresses the issues of time delay and deception attacks in networked control systems. An event-based secure networked predictive control system (ESNPCS) architecture is proposed. The ESNPCS integrates a secure transmission protocol and an event-based networked predictive control. The secure transmission protocol guarantees the integrity, confidentiality and authenticity of transmitted data in networked control systems. The networked predictive control compensates time delay based on the control signal prediction sequence derived from the previous states, control inputs and outputs. The event-based control method alleviates the adverse influence of network congestion through the event trigger conditions. A theoretical result using the Lyapunov theory is obtained for the stability of the ESNPCS. Practical experiments are implemented to demonstrate the effectiveness of the proposed ESNPCS. [ABSTRACT FROM AUTHOR]

Background: Multiple sclerosis (MS) lesions typically form around a central vein that can be visualized with FLAIR* MRI, creating the central vein sign (CVS) which may reflect lesion pathophysiology. Herein we used gradient echo plural contrast imaging (GEPCI) MRI to simultaneously visualize CVS and measure tissue damage in MS lesions. We examined CVS in relation to tissue integrity in white matter (WM) lesions and among MS subtypes. Objective: We aimed to determine if CVS positive lesions were specific to MS subtype, if CVS can be detected consistently among readers using the GEPCI method, and if there were differences in tissue damage in lesions with vs without CVS. Subjects and Methods: Thirty relapsing-remitting MS (RRMS) subjects and 38 primary and secondary progressive MS (PMS) subjects were scanned with GEPCI protocol at 3T. GEPCI T2*-SWI images were generated to visualize CVS. Two investigators independently evaluated WM lesions for CVS and measured lesion volumes. To estimate tissue damage severity, total lesion volume, and mean lesion volume, R2t*-based tissue damage score (TDS) of individual lesions and tissue damage load (TDL) were measured for CVS+, CVS-, and confluent lesions. Spearman correlations were made between MRI and clinical data. One-way ANCOVA with age and sex as covariates was used to compare measurements of CVS+ vs CVS- lesions in each individual. Results: 398 of 548 lesions meeting inclusion criteria showed CVS. Most patients had ≥40% CVS+ lesions. CVS+ lesions were present in similar proportion among MS subtypes. Interobserver agreement was high for CVS detection. CVS+ and confluent lesions had higher average and total volumes vs CVS- lesions. CVS+ and confluent lesions had more tissue damage than CVS- lesions based on TDL and mean TDS. Conclusion: CVS occurred in RRMS and PMS in similar proportions. CVS+ lesions had greater tissue damage and larger size than CVS- lesions. [ABSTRACT FROM AUTHOR]

Contamination and adverse effects from various pollutants often appear in abandoned industrial regions. Thus, nine groundwater samples were collected from the vicinity of the fluorochemical industry in Fuxin City, Liaoning Province, to determine concentrations of the ten heavy metals arsenic (As), chromium (Cr), cadmium (Cd), lead (Pb), nickel (Ni), copper (Cu), manganese (Mn), zinc (Zn), iron (Fe) and mercury(Hg), as well as those of fluorine (F−) and eighteen poly- and perfluorinated substances (PFASs), analyse correlation relationships, and assess the health risks for different age groups. The results showed that the levels of fluorine (F−) (0.92–4.42 mg·L−1), Mn (0.0005–4.91 mg·L−1) and Fe (1.45–5.61 mg·L−1) exceeded the standard limits for drinking water. Short chain perfluorobutanoic acid (PFBA) (4.14–2501.42 ng·L−1), perfluorobutane sulfonate (PFBS) (17.07–51,818.61 ng·L−1) and perfluorohexanoic acid (PFHxA) (0.47–936.32 ng·L−1) were the predominant substances from the PFASs group. No individual PFASs levels had significant relationships with F− or heavy metal contents. There was a positive relationship between short chain PFASs concentrations and water depth and a negative relationship between long chain PFASs concentration and water depth. The hazard quotient (HQ) decreased in the order F− > heavy metals > PFASs and also decreased for older age groups. In addition, As, Fe, Mn and perfluorooctanoic acid (PFOA) were the main sources of risk from the heavy metal and PFASs groups, respectively. [ABSTRACT FROM AUTHOR]

First, mobility cannot be turned on and off like a water tap; mobility restriction always leads to mobility redistribution. Remote work, or more precisely work from home, is widely expected to become a new normal (Raghunath & Tan, 2020). Remote work and the pandemic are related to each other not only because they reduce mobility but also because they both redistribute mobility. Persons engaged in remote work "outsourced" their mobility needs to a new army of specialist mobility labour. [Extracted from the article]

Numerous factors can influence the force exerted by clear aligners on teeth. This study aimed to investigate the stability of the force delivered by two different material appliances. 90 clear aligners with 2 materials and three different activations were designed and fabricated. Then, a device was employed to measure the force generated by the two types of PET-G material appliances immersed in artificial saliva for 0, 3, 7, 10, 14 days. Scanning electron microscopy was applied to observe the morphologic alterations on the aligner surfaces, respectively. The forces generated by different activation appliance exhibited differently, 0.0 mm < 0.1 mm < 0.2 mm. In addition, increasing the immersion times and the orthodontic force also decreased, but the forces decreased differently. Compared with the forces of conventional PETG appliances with 0.20 mm activation, the modified PETG appliances with the same activation exhibited significantly higher mean force. When comparing the mean force for modified PETG appliances after 10 and 14 days with conventional PETG appliances, the delivery forces exhibited significant differences (P < 0.05). The force delivered by both materials decreased obviously following artificial saliva immersion, and the force generated by modified aligners exhibited better stability than conventional aligners. [ABSTRACT FROM AUTHOR]

Impaired homeostasis of copper has been linked to different pathophysiological mechanisms in neurodegenerative diseases and oxidative injury has been proposed as the main mechanism. This study aims to use curcumin, a widely used antioxidative and anti-apoptotic agent, to exert the neuroprotective effect against copper in vitro and illuminate the underlying mechanism. The effect of curcumin was examined by using a cell counting kit-8 assay, flow cytometry, immunofluorescence, spectrophotometer, and western blot. Results revealed that after pretreatment with curcumin for 3 h, copper-induced toxicity and apoptosis show a significant decline. Further experiments showed that curcumin not only decreased the production of ROS and MDA but also increased the activities of the ROS scavenging enzymes SOD and CAT. Moreover, curcumin treatment alleviated the decrease in mitochondrial membrane potential and the nuclear translocation of cytochrome c induced by copper. The protein levels of pro-caspase 3, pro-caspase 9, and PARP1 were up-regulated and the Bax/Bcl-2 ratio was down-regulated in the presence of curcumin. Taken together, our study demonstrates that curcumin has neuroprotective properties against copper in SH-SY5Y cells and the potential mechanisms might be related to oxidative stress and mitochondrial apoptosis. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic urges us to rethink the analytical relations between China, Asia and other parts of the world. Many of what had appeared to be "Chinese characteristics" at the early stage of the outbreak turned out to be common phenomena worldwide. Apparently minor differences, such as the penetration rate of e-commerce, matter a great deal. This essay contributes to this intellectual remapping by proposing two arguments. First, the essay aims to explain the similar governmental reactions in China and other parts of the world—the initial reluctance followed by drastic lockdown—by pointing to the "gyroscope-economy" model that dominates many societies. The economy is structurally imbalanced and has thus become exceedingly dependent on the movements of people, goods and capital, much like a gyroscope, which cannot balance unless spun fast. Second, the essay examines several Chinese-specific characteristics of the gyroscope-like economy, namely the broad-based participation and the high growth rate coupled with low welfare provisions, competitiveness and precariousness. These features are attributable to a combination of hypermobility and authoritarianism. The pandemic may intertwine the two more deeply, in China and beyond. [ABSTRACT FROM AUTHOR]

Wetting deformation of the rockfill material, which is generated by particle sliding, breakage, and rearrangement, plays a vital role in earth-rockfill dam deformation that determines the safety of the dam. However, the previous wetting deformation particle breakage test was performed under the conventional stress path, which could not reflect the influence of stress path. This paper investigates the particle breakage of the basalt rockfill used in the Gushui dam during wetting deformation tests under the equal stress ratio path and drained triaxial shearing tests under the complex stress path. The results indicate that stress path, stress level, stress intensity, and particle breakage determine the wetting deformation under the equal stress ratio path. Under a low confining pressure (1,000 kPa), rockfill particle sliding and roll over are loosely constrained, and negligible particle breakage occurs during wetting deformation, which is mostly generated by particle sliding and rearrangement. Under a high confining pressure (2,000 kPa), rockfill particle sliding and roll over are more constrained. Thus, the contact force significantly increases and significant particle breakage occurs during wetting deformation. In addition, the relationship between the relative particle breakage index and plastic work under the equal stress ratio path and the following wetting deformation period can be simulated with a hyperbolic formulation, which cannot reasonably simulate the particle breakage under the transitional stress path after wetting deformation. The wetting deformation function under the equal stress ratio path was developed to incorporate the influence of the particle breakage and stress path. [ABSTRACT FROM AUTHOR]

For a hybrid magnetically suspended flywheel (MSFW) rotor suspended by permanent magnet biased active magnetic bearing (AMB) and passive magnetic bearing (PMB), the dynamic functions are nonlinear and coupling among different degrees of freedom (DOFs). In this article, the nonlinear dynamic functions in two controllable DOFs of the hybrid MSFW rotor are developed based on the equivalent magnetic circuit, and then the nonlinear dynamic function is linearized by using the state feedback exact linearization (SFEL) in order to minimize the coupling in two controllable DOFs. Furthermore, an optimal control based on the SFEL model is designed to reduce displacement runout and coupling among two controllable DOFs of the hybrid MSFW rotor at the rated speed. Finally, the simulation and experimental results validate the effectiveness of the optimal control based on SFEL model, and the stability of the hybrid MSFW rotor with an impulse-type disturbance is improved. [ABSTRACT FROM AUTHOR]

An active magnetic bearing (AMB) system is used to suspend the yaw gimbal of three-axis inertially stabilized platform (ISP) to minimize the friction. The dynamic functions of three gimbals in ISP are developed. The base coupling at dynamic base plate is stronger than that at static base plate, and the gimbal coupling among three gimbals increases with the number of unlocked gimbals. Therefore, a cross-feedback control scheme is designed to minimize the base coupling and the gimbal coupling, and then the multi-input multioutput system of three-axis ISP with coupling terms is simplified into three decoupled single-input single-output systems. Experimental results verify that the yaw gimbal suspended by AMB system has better vibration isolation ability than the roll gimbal supported by mechanical bearing, and the gimbal coupling and the base coupling are effectively suppressed by the cross-feedback control scheme. [ABSTRACT FROM AUTHOR]

Himalayan leucogranites are widely distributed in the North Himalayan gneiss dome (NHGD) and at the top of the Greater Himalayan Crystalline Complex (GHC) and are generally controlled by detachment faults. The ages of these prekinematic, synkinematic, and postkinematic leucogranites can be used to limit the activity of detachment structures (such as the South Tibetan Detachment System, STDS). Research on the STDS activity time in the eastern Himalayas is relatively sparse. In this study, the zircon and monazite U–Th–Pb geochronology of synkinematic and postkinematic leucogranites, which are affected by the STDS and NHGD, in four areas (Lhozhag, Kuju, Xiaozhan, and Cuonadong) in Shannan City, Tibet, China, was measured. The results show that the oldest synkinematic two‐mica granite from Lhozhag, which is affected by the STDS, is 24–25 Ma, so the time of STDS activity is at or slightly earlier than 25 Ma. The youngest synkinematic leucogranite is the garnet‐bearing muscovite granite in Cuonadong at 18.4 Ma. The oldest undeformed postkinematic leucogranite (not affected by the STDS) is the muscovite granite in Xiaozhan at 17.4 Ma. Therefore, the end of STDS activity can be limited to 18.4–17.4 Ma. The STDS includes three forms: detachment fault in the NHGD (northern extension of the STDS), the inner STDS between the GHC and Tethyan Himalayan Sequence, and the outer STDS at the bottoms of synformal klippes. In this paper, the active time limits of the above three kinds of detachment zones are comprehensively summarized. Based on this work, the northward extension (ductile deformation) time of the STDS in the region is considered to be 28–17 Ma. The exhumation of the GHC is mainly controlled by in‐sequence shearing: first, the South Tibet Thrust system (predecessor of the STDS) at the top of the GHC thrust southward at 45–28 Ma, then the High Himalayan Discontinuity fault in the middle of the GHC forms south‐vergent ductile thrusts at 28–17 Ma, and finally, the Main Central Thrust at the bottom of the GHC thrust southward at 17–9 Ma. [ABSTRACT FROM AUTHOR]

A 35‐year‐old man with an enhancing tumefactive brain lesion underwent biopsy, revealing inflammatory demyelination. We used quantitative Gradient‐Recalled‐Echo (qGRE) MRI to visualize and measure tissue damage in the lesion. Two weeks after biopsy, qGRE showed significant R2t* reduction in the left optic radiation and surrounding tissue, consistent with the histopathological and clinical findings. qGRE was repeated 6 and 14 months later, demonstrating partially recovered optic radiation R2t*, in concert with improvement of the hemianopia to ultimately involve only the lower right visual quadrant. These results support qGRE metrics as in vivo biomarkers for tissue damage and longitudinal monitoring of demyelinating disease. [ABSTRACT FROM AUTHOR]

The technological advancement in the communication and control infrastructure helps those smart households (SHs) that more actively participate in the incentive-based demand response (IBDR) programs. As the agent facilitating the SHs’ participation in the IBDR program, load aggregators (LAs) need to comprehend the available SHs’ demand response (DR) capacity before trading in the day-ahead market. However, there are few studies that forecast the available aggregated DR capacity from LAs’ perspective. Therefore, this article proposes a forecasting model aiming to aid LAs forecast the available aggregated SHs’ DR capacity in the day-ahead market. First, a home energy management system is implemented to perform optimal scheduling for SHs and to model the customers’ responsive behavior in the IBDR program; second, a customer baseline load estimation method is applied to quantify the SHs’ aggregated DR capacity during DR days; third, several features which may have significant impacts on the aggregated DR capacity are extracted and they are processed by principal component analysis; and finally, a support vector machine based forecasting model is proposed to forecast the aggregated SHs’ DR capacity in the day-ahead market. The case study indicates that the proposed forecasting framework could provide good performance in terms of stability and accuracy. [ABSTRACT FROM AUTHOR]

The Cuonadong Dome in southern Tibet is a newly discovered gneiss dome in the Tethys Himalaya. Here, we investigate the Late Cambrian augen gneiss (orthogneiss) within the core of this dome to address the controversy surrounding early Palaeozoic tectonic evolution of the northern margin of eastern Gondwana. We report new zircon laser ablation multicollector inductively coupled plasma mass spectrometry (LA‐(MC‐)ICP‐MS) U‐Pb ages, Lu‐Hf isotopes, whole‐rock major and trace element geochemistry, and Sr‐Nd‐Pb data on representative samples from the granitic gneiss. The weighted mean of 116 analyses of zircon grains yields an age of 498.2 ± 1.5 Ma (mean square weighted deviation [MSWD] = 1.2). Forty‐one spots analyses on these grains show consistent εHf (t) values of −2 to +4 (average = +1.1), corresponding to Hf crustal model age (TDM2) of 1.3 to 1.6 Ga (average = 1.39 Ga). The orthogneiss (metagranite) is characterized by high Si and K contents, with low Al, Mg, and Ti, and A/CNK values ranging from 0.87 to 0.98 with an average of 0.92, indicating a metaluminous composition and I‐type granitoid affinity. The granitoid displays significant enrichment in light rare earth elements (LREEs) and relatively flat high rare earth element (HREE) patterns, with strong negative Eu anomalies (Eu/Eu* = 0.26–0.31). The primitive mantle‐normalized trace elements show a relative enrichment in large‐ion lithophile elements, such as Rb, and high‐field strength elements, such as Th, U, Zr, and Hf, with depletion in Ba, Nb, Ta, Sr, P, and Ti. The rocks show high initial 87Sr/86Sr ratios (0.7221–0.7248) and low εNd (t) values (−8.9 to −7.3) with Nd model ages (TDM) of 1.79–1.91 Ga. Their radiogenic Pb isotopic compositions show (206Pb/204Pb)t = 18.804–19.110, (207Pb/204Pb)t = 15.730–15.768, and (208Pb/204Pb)t = 38.409–39.054, indicating an ancient upper middle continental crustal origin. Our study shows that the protolith of the metagranite was most likely derived from the partial melting of upper continental crust with a minor contribution of depleted mantle materials. Through integration of the regional information on early Palaeozoic magmatism and metamorphic events, we contend that the protolith of the Cuonadong granitic gneiss formed in an accretionary setting associated with the early Palaeozoic Proto‐Tethys Oceanic plate subduction beneath the Gondwana continent. [ABSTRACT FROM AUTHOR]

Background: Multiple sclerosis (MS) is a chronic disease affecting the human central nervous system (CNS) and leading to neurologic disability. Although conventional MRI techniques can readily detect focal white matter (WM) lesions, it remains challenging to quantify tissue damage in normal-appearing gray matter (GM) and WM.Purpose: To demonstrate that a new MRI biomarker, R2t*, can provide quantitative analysis of tissue damage across the brain in MS patients in a single scan.Study Type: Prospective.Subjects: Forty-four MS patients and 19 healthy controls (HC).Field Strength/sequence: 3T, quantitative gradient-recalled-echo (qGRE), Magnetization-prepared rapid gradient-echo, fluid-attenuated inversion recovery.Assessment: Severity of tissue damage was assessed by reduced R2t*. Tissue atrophy was assessed by cortical thickness and cervical spinal cord cross-sectional area (CSA). Multiple Sclerosis Functional Composite was used for clinical assessment.Results: R2t* in cortical GM was more sensitive to MS damage than cortical atrophy. Using more than two standard deviations (SD) reduction versus age-matched HC as the cutoff, 48% of MS patients showed lower R2t*, versus only 9% with lower cortical thickness. Significant correlations between severities of tissue injury were identified among 1) upper cervical cord and several cortical regions, including motor cortex (P < 0.001), and 2) adjacent regions of GM and subcortical WM (P < 0.001). R2t*-defined tissue cellular damage in cortical GM was greater relative to adjacent WM. Reductions in cortical R2t* correlated with cognitive impairment (P < 0.01). Motor-related clinical signs correlated most with cervical cord CSA (P < 0.001).Data Conclusion: Reductions in R2t* within cortical GM was more sensitive to tissue damage than atrophy, potentially allowing a reduced sample size in clinical trials. R2t* together with structural morphometry suggested topographic patterns of regions showing correlated tissue damage throughout the brain and the cervical spinal cord of MS patients.Level Of Evidence: 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;49:487-498. [ABSTRACT FROM AUTHOR]

In traditional Chinese medicine (TCM), Acori Tatarinowii Rhizoma (ATR) is widely used to treat memory and cognition dysfunction. This study aimed to confirm evidence regarding the potential therapeutic effect of ATR on Alzheimer’s disease (AD) using a system network level based in silico approach. Study results showed that the compounds in ATR are highly connected to AD-related signaling pathways, biological processes, and organs. These findings were confirmed by compound-target network, target-organ location network, gene ontology analysis, and KEGG pathway enrichment analysis. Most compounds in ATR have been reported to have antifibrillar amyloid plaques, anti-tau phosphorylation, and anti-inflammatory effects. Our results indicated that compounds in ATR interact with multiple targets in a synergetic way. Furthermore, the mRNA expressions of genes targeted by ATR are elevated significantly in heart, brain, and liver. Our results suggest that the anti-inflammatory and immune system enhancing effects of ATR might contribute to its major therapeutic effects on Alzheimer’s disease. [ABSTRACT FROM AUTHOR]

Cobalt-based catalysts can replace the homologous group-9 rhodium-based ones. Herein, we used density functional theory (DFT) calculations to predict the synthesis of 2,3-dihydropyridines using α,β-unsaturated oxime pivalates and alkenes catalysed by [Cp*CoOAc]+ instead of [Cp*RhOAc]+. The catalytic cycle involves reversible acetate-assisted metalation-deprotonation, migratory insertion of alkenes, and reductive elimination/N-O cleavage. The migratory insertion of alkenes was determined to be the rate-determining step, and the reaction is irreversible due to the strongly exergonic reductive elimination/NO cleavage. When using the CF3-substituted Cp*Co(III) catalyst, the apparent activation energy indicates that the title reaction can proceed at higher temperatures. Electron-withdrawing substituent groups on Cp* facilitate the reaction. In contrast, substituting phenyl with the electron-deficient p-CF3-phenyl at the 2-position of α,β-unsaturated oxime pivalate hinders the reaction, and so does the use of polarized alkenes with electron-withdrawing substituent groups [ABSTRACT FROM AUTHOR]

Since the early 1990s, the Chinese government replaced strict control over outmigration with measures of ‘infrastructural governance’. Instead of dictating who can and who cannot leave, the state manages migration by influencing the sociotechnical conditions of mobility, for instance by defining what responsibilities commercial intermediaries should shoulder and what training a migrant should receive before departure. This article unpacks infrastructural governance by examining the working of ‘base’, orjidiin Chinese. A base is a tight cluster of public and private institutions in a labour source place, designated by the government as an important player in the recruitment of migrant workers. The base manages migration by conditioning the activities that lead to migration, such as how people choose destinations, make payments, and deal with uncertainties in preparing for migration. The base also works on migrants’ relations with family members, village cadres and fellow migrants in order to shape their mobilities. The ethnographic research on the base shows that, infrastructural governance regulates migration effectively, but makes migration more complicated and more costly for the migrants. Infrastructural governance empowers commercial intermediaries and local government, and as such affects broader social relations in the community. [ABSTRACT FROM PUBLISHER]

Since the proclamation of a mobility turn in the 2000s, scholars have populated the field with invaluable insights on what it means to move, and what the politics of movement are. One particularly useful thread revolves around the issue of infrastructures, which have generally been taken to mean the manifest forms of moorings and fixities that help order and give shape to mobilities. Yet, while significant inroads have been made in delineating the morphologies of transport infrastructures, mobilities research has been relatively reticent about the organisational structures, orders and arrangements that give rise to another key mobile phenomenon of our time — international migration. In this editorial introduction, we lay down some groundwork on the productive and political nature of infrastructures that likewise affect and inform the way (im)mobilities are contingently created and parsed in migration. Looking through the prism of East and Southeast Asia and its migration infrastructures, we take advantage of the ‘new’ infrastructural configurations in an emerging empirical context to point to some directions by which mobilities researchers can more rigorously interrogate ‘migration’ as another socially meaningful and specific form of mobility that exceeds a mere displacement of people or change in national domicile. [ABSTRACT FROM PUBLISHER]

A density functional theory study is performed on the reactions of α,β-unsaturated oxime pivalates and alkenes through Cp*RhIII-catalyzed (Cp* = pentamethylcyclopentadienyl) C-H activation. The catalytic cycle involves reversible metalation-deprotonation, migratory alkene insertion, pivaloyl transfer to the Rh center, and reductive elimination, among other steps. The results show that the migratory alkene insertion is rate-determining and that the reductive elimination to form the product-ligated species makes the reaction irreversible (exergonic by 60 kcal/mol). If the electron-donating ability of the substituents on the cyclopentadienyl (Cp) ligand is increased or an electron-withdrawing group is introduced into the terminus of the alkene, the apparent activation energy of the reaction increases. In contrast, if a stronger electron-donating group is introduced at the 2-position of the α,β-unsaturated oxime pivalate, the apparent activation energy of the reaction decreases greatly, and the reaction can be performed at room temperature. On the other hand, for phenyl groups at the 2-position, the introduction of a more electron-deficient p-CF3- phenyl group increases the apparent activation energy. Finally, the diastereoselectivity of the reaction with cyclohexylethylene as the substrate is attributable to a clash between the cyclohexyl group and the α,β-unsaturated oxime pivalate. [ABSTRACT FROM AUTHOR]

Methodological nationalism takes the nation-state as a pre-given container of social life, and thereby treats internal and international migrations as separate matters. Epistemological behaviouralism redresses this by removing the conceptual divide between internal and international but is problematic in regarding migration as a human behaviour distinct in itself. In explaining why and how these two pitfalls need to be addressed in tandem, I first trace how these contrasting viewpoints are historically deeply intertwined. I then draw on examples from China to demonstrate that migrations should be understood as composites of actions carried out by multiple actors and institutions, which in their turn lead to and become part of other social processes. Internal and international migrations are interlinked as constituted and constitutive assemblages. In the case of China, the nation-state is a central link between the two, and is at the same time itself reconfigured by mobilities. Instead of promoting migration as a subject matter in its own right and migration studies as a distinct field, this article seeks to turn migration into an analytical perspective to examine broad social changes. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]