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In this paper, on–off switching digitization of a W-band variable gain power amplifier (VGPA) with above 60 dB dynamic range is introduced for large-scale phased array. Digitization techniques of on–off switching modified stacking transistors with partition are proposed to optimize configuration of control sub-cells. By the proposed techniques, gain control of a radio frequency variable gain amplifier (VGA) could be highly customized for both coarse and fine switching requirements instead of using additional digital-to-analog converters to tune the overall amplifier bias. The designed VGA in 130 nm SiGe has achieved switchable gain range from −46.4 to 20.6 dB and power range from −25.0 to 15.7 dBm at W band. The chip size of the fabricated VGPA is about 0.31 mm × 0.1 mm.
In contemporary neuroimaging studies, it has been observed that patients with major depressive disorder (MDD) exhibit aberrant spontaneous neural activity, commonly quantified through the amplitude of low-frequency fluctuations (ALFF). However, the substantial individual heterogeneity among patients poses a challenge to reaching a unified conclusion.
Methods
To address this variability, our study adopts a novel framework to parse individualized ALFF abnormalities. We hypothesize that individualized ALFF abnormalities can be portrayed as a unique linear combination of shared differential factors. Our study involved two large multi-center datasets, comprising 2424 patients with MDD and 2183 healthy controls. In patients, individualized ALFF abnormalities were derived through normative modeling and further deconstructed into differential factors using non-negative matrix factorization.
Results
Two positive and two negative factors were identified. These factors were closely linked to clinical characteristics and explained group-level ALFF abnormalities in the two datasets. Moreover, these factors exhibited distinct associations with the distribution of neurotransmitter receptors/transporters, transcriptional profiles of inflammation-related genes, and connectome-informed epicenters, underscoring their neurobiological relevance. Additionally, factor compositions facilitated the identification of four distinct depressive subtypes, each characterized by unique abnormal ALFF patterns and clinical features. Importantly, these findings were successfully replicated in another dataset with different acquisition equipment, protocols, preprocessing strategies, and medication statuses, validating their robustness and generalizability.
Conclusions
This research identifies shared differential factors underlying individual spontaneous neural activity abnormalities in MDD and contributes novel insights into the heterogeneity of spontaneous neural activity abnormalities in MDD.
This case report discusses a rare occurrence of type II Kounis syndrome, characterised by an acute myocardial infarction triggered by an allergic reaction. The patient, a young adult male, experienced urticaria soon after eating oysters, which quickly escalated to severe chest discomfort. Despite lacking typical cardiac risk factors, the electrocardiogram showed indications of ST-elevation myocardial infarction. This condition was further complicated by ventricular fibrillation, necessitating urgent life-saving measures. This case demonstrates the intricate and often overlooked relationship between hypersensitivity reactions and cardiovascular events. It highlights the necessity for increased vigilance and rapid diagnostic and treatment approaches in handling Kounis Syndrome, especially in emergency situations. The case underscores the importance of considering allergic causes in acute cardiac scenarios, particularly in patients who do not have standard risk factors for coronary artery disease.
Ceratopsian dinosaurs underwent great changes, including a shift of locomotion mode, enlarged horns and frills, and increased body size. These changes occur alongside the evolution of endocranial morphology and physiology such as the size and shape of the flocculus, hearing range, olfactory ratio, and the reptile encephalization quotient (REQ). However, the evolution of endocranial structures in early ceratopsians is still unclear because of a lack of information on the earliest ceratopsians. Here, we reconstructed the endocasts of three early-diverging ceratopsians including the Late Jurassic Yinlong, and the Early Cretaceous Liaoceratops and Psittacosaurus. These ceratopsians display obvious flocculi, large and separate olfactory bulbs, long and high anterior semicircular canals, and relatively long cochlear ducts. In the evolution of the earliest ceratopsians to early neoceratopsians, changes include the increasing size of the flocculus (which is reduced or absent in late-diverging ceratopsids), the attenuation of the semicircular canals, and the heightening of the anterior semicircular canal (which is shortened in late-diverging ceratopsids). The endocranial structures suggest early-diverging ceratopsians had a higher olfactory acuity and were adapted to hearing higher frequencies than late-diverging ceratopsians. Furthermore, the REQ suggests that Yinlong and Psittacosaurus were more highly encephalized than late-diverging ceratopsians and most extant reptiles. The angle of the lateral semicircular canal suggests that heads in ceratopsians display a transition from a forward posture to a more downward posture. Our new findings are significant for understanding the physiological changes during ceratopsian evolution and also have implications for the evolution of physiology in extant tetrapods.
The two-wheeled legged robot combines the advantages of legged robot and wheeled robot and has high terrain adaptability. Spherical robots are highly resistant to interference during detection. In this paper, a new sphere-wheel-legged robot is designed by combining these three motion modes. This paper begins by introducing the mechanical design, hardware, and software. Then, kinematics and dynamics of wheel-legged motion and spherical motion are analyzed in detail. Subsequently, the controllers for wheel-legged balancing motion, wheel-legged jumping motion, and sphere rolling motion are developed, respectively. Finally, experiments are carried out for different modes. The results demonstrate that the designed robot has excellent locomotor capabilities over different terrains.
The practical implementation of machine learning in flow control is limited due to its significant training expenses. In the present study the convolutional neural network (CNN) trained with the data of the restricted nonlinear (RNL) model is used to predict the normal velocity on a detection plane at $y^+=10$ in a turbulent channel flow, and the predicted velocity is used as wall blowing and suction for drag reduction. An active control test is carried out by using the well-trained CNN in direct numerical simulation (DNS). Substantial drag reduction rates up to 19 % and 16 % are obtained based on the spanwise and streamwise wall shear stresses, respectively. Furthermore, we explore the online control of wall turbulence by combining the RNL model with reinforcement learning (RL). The RL is constructed to determine the optimal wall blowing and suction based on its observation of the wall shear stresses without using the label data on the detection plane for training. The controlling and training processes are conducted synchronously in a RNL flow field. The control strategy discovered by RL has similar drag reduction rates with those obtained previously by the established method. Also, the training cost decreases by over thirty times at $Re_{\tau }=950$ compared with the DNS-RL model. The present results provide a perspective that combining the RNL model with machine learning control for drag reduction in wall turbulence can be effective and computationally economical. Also, this approach can be easily extended to flows at higher Reynolds numbers.
Disaster experiences have long-term effects on disaster preparedness. This study examined the long-term (10-y) effect of disaster severity of the 2008 Wenchuan earthquake on survivors’ disaster preparedness and the moderating effects of household vulnerability.
Methods:
The data were collected in January 2018 covering 30 counties in Wenchuan earthquake-stricken areas. The dependent variable was survivors’ disaster preparedness (including overall, material, knowledge and awareness, and action preparedness) in 2018. Disaster severity included survivors’ housing damage and county death rate caused by the earthquake in 2008. Household vulnerability is a set of conditions that negatively affects the ability of people to prepare for and withstand disaster, proxied by households’ per-capita income and the highest years of schooling of household members. We performed multivariable linear regression models to answer the research questions.
Results:
A higher county death rate was associated with better overall preparedness (β = 0.043; P < 0.05) and knowledge and awareness preparedness (β = 0.018; P < 0.05), but housing damage was not significantly associated with disaster preparedness. The positive association of county death rate with overall preparedness (β = −0.065; P < 0.05) becomes weaker when a household has a higher per-capita income. Also, with the household per-capita income increasing, the associations of county death rate with material preparedness (β = −0.037; P < 0.05) and action preparedness (β = −0.034; P < 0.01) become weaker.
Conclusions:
Disaster severity has positive and long-term effects on survivors’ disaster preparedness. Also, the positive and long-term effects are affected by household vulnerability. Specifically, the positive and long-term effects of disaster severity on disaster preparedness are more substantial when a household is more vulnerable.
This study aimed to analyse the spatial and temporal patterns of disease burden attributed to high BMI (DB-hBMI) from 1990 to 2019 in Belt and Road Initiative (BRI) countries, in light of increasing hBMI prevalence worldwide.
Design:
The study was a secondary analysis of Global Burden of Disease 2019 (GBD 2019) that analysed (using Joinpoint regression analysis) numbers and the age-standardised rate of mortality and disability-adjusted life years (DALY) of hBMI-induced diseases and their trends from 1990 to 2019 and in the final decade.
Setting:
GBD 2019 study data for BRI countries were categorised by country, age, gender and disease.
Participants:
GBD 2019 data were used to analyse DB-hBMI in BRI countries.
Results:
In 2019, China, India and Russia reported the highest mortality and DALY among BRI countries. From 1990 to 2019, the age-standardised DALY increased in Southeast Asia and South Asia, whereas many European countries saw declines. Notably, Bangladesh, Nepal and Vietnam showed the steepest increases, with average annual percentage change (AAPC) values of 4·42 %, 4·19 % and 4·28 %, respectively (all P < 0·05). In contrast, Israel, Slovenia and Poland experienced significant reductions, with AAPC values of –1·70 %, –1·63 % and –1·58 %, respectively (all P < 0·05). The most rapid increases among males were seen in Vietnam, Nepal and Bangladesh, while Jordan, Poland and Slovenia recorded the fastest declines among females. Across most BRI countries, the burden of diabetes and kidney diseases related to hBMI showed a significant uptrend.
Conclusion:
DB-hBMI varies significantly by region, age, gender and disease type across BRI countries. It can pose a substantial threat to public health.
This paper retrospectively analysed the prevalence of macrolide-resistant Mycoplasma pneumoniae (MRMP) in some parts of China. Between January 2013 and December 2019, we collected 4,145 respiratory samples, including pharyngeal swabs and alveolar lavage fluid. The highest PCR-positive rate of M. pneumoniae was 74.5% in Beijing, the highest resistance rate was 100% in Shanghai, and Gansu was the lowest with 20%. The highest PCR-positive rate of M. pneumoniae was 74.5% in 2013, and the highest MRMP was 97.4% in 2019; the PCR-positive rate of M. pneumoniae for adults in Beijing was 17.9% and the MRMP was 10.48%. Among the children diagnosed with community-acquired pneumonia (CAP), the PCR-positive and macrolide-resistant rates of M. pneumoniae were both higher in the severe ones. A2063G in domain V of 23S rRNA was the major macrolide-resistant mutation, accounting for more than 90%. The MIC values of all MRMP to erythromycin and azithromycin were ≥ 64 μg/ml, and the MICs of tetracycline and levofloxacin were ≤ 0.5 μg/ml and ≤ 1 μg/ml, respectively. The macrolide resistance varied in different regions and years. Among inpatients, the macrolide-resistant rate was higher in severe pneumonia. A2063G was the common mutation, and we found no resistance to tetracycline and levofloxacin.
This paper presents an algorithm for solving the inverse dynamics of a parallel manipulator (PM) with offset universal joints (RR–joints) via the Newton–Euler method. The PM with RR–joints increase the joint stiffness and enlarge the workspace but introduces additional joint parameters and constraint torques, rendering the dynamics more complex. Unlike existing studies on PMs with RR–joints, which emphasize the kinematics and joint performance, this paper studies the dynamical model. First, an iterative algorithm is established through a rigid body velocity transformation, which calculates the input parameters of the link velocity and acceleration. A linear system of equations in matrix form is then established for the entire PM through the Newton–Euler method. By using the generalized minimal residual method (GMRES) to solve the equation system, all the forces and torques on the joints can be obtained, from which the required actuation force can be derived. This method is validated through numerical simulations using the automatic dynamic analysis of multibody systems software. The proposed method is suitable for establishing the dynamic model of complex PMs with redundant or hybrid structures.
Gut microbiome changed dramatically during pregnancy and played important roles in metabolic status and reproductive endocrinology in mammals. However, investigating the functional microbiota and metabolites to improve the reproductive performance and understanding the host–microbiota interaction are still arduous tasks. This study aims to reveal the dominant strains and metabolites that improve the reproductive performance. We analyzed the fecal microbiota composition and metabolic status of higher yield Chinese pig breed Meishan (MS) sows and lower yield but widespread raised hybrid pig breed Landrace × Yorkshire (L × Y) sows on days 28 and 100 of gestation. Results showed that MS sows had higher litter sizes and steroid hormone level but lower short-chain fatty acid level in feces. Fecal metabolomic analysis revealed that MS sows showed a different metabolic status compared with L × Y sows both at early and late pregnancy, which enriched with phenylpropanoid biosynthesis, bile secretion, steroid hormone biosynthesis, and plant secondary metabolite biosynthesis. In addition, 16S rDNA and internal transcribed spacer sequencing indicated that MS sows showed different structures of microbiota community and exhibited an increased bacterial α-diversity but non-differential fungal α-diversity than L × Y sows. Moreover, we found that the litter sizes and bacteria including Sphaerochaeta, Solibacillus, Oscillospira, Escherichia–Shigella, Prevotellaceae_UCG-001, dgA-11_gut_group, and Bacteroides, as well as fungi including Penicillium, Fusarium, Microascus, Elutherascus, and Heydenia both have positive association to the significant metabolites at the early pregnancy. Our findings revealed significant correlation between reproductive performance and gut microbiome and provided microbial and metabolic perspective to improve litter sizes and steroid hormones of sows.
Direct numerical simulations are performed to study temporal variations of the wall shear stresses and flow dynamics in the turbulent pulsatile pipe flow. The mechanisms, responsible for the paradoxical phenomenon for which the amplitude of the oscillating wall shear stress in the turbulent flow is smaller than that in the laminar flow for the same pulsation conditions, are investigated. It is shown that the delayed response of turbulence in the buffer layer generates a large magnitude of the radial gradient of the Reynolds shear stress near the wall, which counteracts the effect of the oscillating pressure gradient on the change of the streamwise velocity and hence reduces the amplitude of the wall shear stress. Such a delayed response consists of two processes: the delayed development of near-wall streaks and the subsequent energy redistribution from the streamwise velocity fluctuation to the other two co-existing components. This is a dynamical manifestation of the viscoelasticity of turbulent eddies. As the frequency is reduced, the variation of the friction Reynolds number results in a phase-wise variation of the time scale and intensity of the turbulence response, causing the hysteresis of the wall shear stress. Such a phase asymmetry is amplified by the increase of the pulsation amplitude. An examination of the energy spectra reveals that the near-wall streaks are stretched in the streamwise direction during the acceleration phase, and then break up into small-scale structures in the deceleration phase, accompanied by the enhanced dissipation that transforms the turbulent kinetic energy into heat.
Childhood maltreatment is an established risk factor for psychopathology. However, it remains unclear how childhood traumatic events relate to mental health problems and how the brain is involved. This study examined the serial mediation effect of brain morphological alterations and emotion-/reward-related functions on linking the relationship from maltreatment to depression. We recruited 156 healthy adolescents and young adults and an additional sample of 31 adolescents with major depressive disorder for assessment of childhood maltreatment, depressive symptoms, cognitive reappraisal and anticipatory/consummatory pleasure. Structural MRI data were acquired to identify maltreatment-related cortical and subcortical morphological differences. The mediation models suggested that emotional maltreatment of abuse and neglect, was respectively associated with increased gray matter volume in the ventral striatum and greater thickness in the middle cingulate cortex. These structural alterations were further related to reduced anticipatory pleasure and disrupted cognitive reappraisal, which contributed to more severe depressive symptoms among healthy individuals. The above mediating effects were not replicated in our clinical group partly due to the small sample size. Preventative interventions can target emotional and reward systems to foster resilience and reduce the likelihood of future psychiatric disorders among individuals with a history of maltreatment.
This article presents relevant data on the usage of the sinograph jīng 椋 and revisits its origin and lexical form on the basis of textual examination, using primary sources from China, Korea and Japan. The authors conclude that jīng 椋, and its variants jīng, jīng 稤 and the miscopied form lǜe 掠, originated from its radical character jīng 京, meaning “warehouse, granary”, and that jīng 椋 was widely used in Koguryŏ, Paekche, Silla and Japan. Historical documents during the Koryŏ period also attest to the use of jīng 椋. The authors have reconstructed the lexical form of jīng 椋 as the disyllabic pre-Old Korean **kuL.raH in Paekche and **koL.raH in Silla, and the monosyllabic Old Korean *kolR as a Sillaic substratum that underwent the syllabic contraction and liquid change **-r- > *-l, that is **koL.raH > *kolR. The Western Old Japanese kun'yomi of jīng 椋, kura, is a loan from pre-Old Korean **kuL/koL.raH that took place before the eighth century.
In this work, we experimentally investigate the dependence of the stimulated Raman scattering (SRS) effect on the seed linewidth of a high-power nanosecond superfluorescent fiber source (ns-SFS). The results reveal that the SRS in the ns-SFS amplifier is significantly influenced by the full width at half maximum (FWHM) of the ns-SFS seed, and there is an optimal FWHM linewidth of 2 nm to achieve the lowest SRS in our case. The first-order SRS power ratio increases rapidly when the seed’s linewidth deviates from the optimal FWHM linewidth. By power scaling the ns-SFS seed with the optimal FWHM linewidth, a narrowband all-fiberized ns-SFS amplifier is achieved with a maximum average power of 602 W, pulse energy of 24.1 mJ and corresponding peak power of 422.5 kW. This is the highest average power and pulse energy achieved for all-fiberized ns-SFS amplifiers to the best of our knowledge.
The production of broadband, terawatt terahertz (THz) pulses has been demonstrated by irradiating relativistic lasers on solid targets. However, the generation of extremely powerful, narrow-band and frequency-tunable THz pulses remains a challenge. Here, we present a novel approach for such THz pulses, in which a plasma wiggler is elaborated by a table-top laser and a near-critical density plasma. In such a wiggler, the laser-accelerated electrons emit THz radiations with a period closely related to the plasma thickness. The theoretical model and numerical simulations predict that a THz pulse with a laser–THz energy conversion of over 2.0%, an ultra-strong field exceeding 80 GV/m, a divergence angle of approximately 20° and a center frequency tunable from 4.4 to 1.5 THz can be generated from a laser of 430 mJ. Furthermore, we demonstrate that this method can work across a wide range of laser and plasma parameters, offering potential for future applications with extremely powerful THz pulses.
Sterol regulatory element-binding protein 2 (SREBP2) is considered to be a major regulator to control cholesterol homoeostasis in mammals. However, the role of SREBP2 in teleost remains poorly understand. Here, we explored the molecular characterisation of SREBP2 and identified SREBP2 as a key modulator for 3-hydroxy-3-methylglutaryl-coenzyme A reductase and 7-dehydrocholesterol reductase, which were rate-limiting enzymes of cholesterol biosynthesis. Moreover, dietary palm oil in vivo or palmitic acid (PA) treatment in vitro elevated cholesterol content through triggering SREBP2-mediated cholesterol biosynthesis in large yellow croaker. Furthermore, our results also found that PA-induced activation of SREBP2 was dependent on the stimulating of endoplasmic reticulum stress (ERS) in croaker myocytes and inhibition of ERS by 4-Phenylbutyric acid alleviated PA-induced SREBP2 activation and cholesterol biosynthesis. In summary, our findings reveal a novel insight for understanding the role of SREBP2 in the regulation of cholesterol metabolism in fish and may deepen the link between dietary fatty acid and cholesterol biosynthesis.
The Community Research Advisory Council (C-RAC) of the Johns Hopkins Institute for Clinical and Translational Research was established in 2009 to provide community-engaged research consultation services. In 2016–2017, C-RAC members and researchers were surveyed on their consultation experiences. Survey results and a 2019 stakeholder meeting proceeding helped redesign the consultation services. Transitioning to virtual consultations during COVID-19, the redesigning involved increasing visibility, providing consultation materials in advance, expanding member training, and effective communications. An increase in consultations from 28 (2009–2017) to 114 (2020–2022) was observed. Implementing stakeholder-researcher inputs is critical to holistic and sustained community-engaged research.
It is very challenging for robots to perform grinding and polishing tasks on surfaces with unknown geometry. Most existing methods solve this problem by modeling the relationship between the force sensing information and surface normal vectors by analyzing the forces on special end tools such as spherical tools and cylindrical tools and simplified friction model. In this paper, we propose a normal vectors learning method to simultaneously control end-effector force and direction on unknown surfaces. First, the relation that mapping the force sensing information to the surface normal vectors is learned from the demonstrated data on the known plane using locally weighted regression. Next, the learned relation is used to estimate surface normal vectors on the unknown surface. To improve the force control precision on the unknown geometry surface, the adaptive force control is developed. To improve the direction control precision due to friction, the iterative learning control is developed. The proposed method is verified by comparative simulations and experiments using the Franka robot. Results show that the end-effector can be controlled perpendicular to the surface with a certain force.
The axial offset joint has two rotating axes that do not intersect but have a specific offset in space. It is used widely in parallel manipulators (PMs). The offset-joint workspace can directly affect the PM workspace. This study performed a theoretical derivation and workspace analysis of a class of axial offset joints. First, a theoretical parametric model describing the rotation range of the offset joint is established that considers the interference of the offset joint because of the contact between the upper- and lower-joint brackets during movement. Second, the analytical expressions of the offset-joint workspace are formulated based on the coordinate system transformation. The offset-joint workspace is theoretically calculated in this study using formulations. Then, through a comparative analysis, the superiority of the offset joint compared with the universal joint is verified. The theoretical formulations in this paper can be used to calculate the workspace of a class of axial offset joints. Finally, based on a workspace analysis of three types of PMs using offset, universal, and spherical joints, the offset-joint PM workspace is much larger than those of the other two types.