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Minimal Model (MM) is the top-scoring model for assessing physiological characteristics to diagnose the potential or onset of type 2 diabetes mellitus (T2DM) through the intravenous glucose tolerance test (IVGTT) for the past four decades. Nevertheless it has been arguable that MM method either overestimates glucose effectiveness (GE) or underestimates insulin sensitivity (IS) in some cases by both biologists through in vivo experiments and mathematicians by analysis and/or simulations. We propose a novel model including the interstitial insulin according to physiology and adapted from the well accepted Sturis’ model for the glucose-insulin metabolic system suitable to the IVGTT setting. Our model consistently overcomes the aforementioned defects in a subgroup of subjects. In addition, the variable X for insulin action in MM might be appropriately interpreted as an increment of insulin in the interstitial space in response to the bolus stimulus, rather than being proportional to the interstitial insulin as believed.

As important loads in first-class loads， the large data center demands a highly reliable power supply. In addition to a dual power supply， the center is also equipped with an emergency power supply system. The traditional busbar automatic transfer switch （BATS） that meets the N-1 principle can no longer satisfy the demand of the center. First of all， the paper analyzes the limitations of conventional BATS； then， the hardware of the BATS is designed based on specific engineering practice. Moreover， the switch logic of the automatic switchover is designed to meet the demand of the center for high power supply continuity under the condition of N-2 contingencies such as overload of the main transformer， power loss of the main power supply， failure to operate and so on. Finally， the feasibility of the device is verified by RTDS （real time digital simulator） to provide a design reference for the data center to improve the power supply reliability through BATS in the future.

Abstract Background Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is an inflammatory disease of the central nervous system (CNS) in which antibodies within the serum and cerebrospinal fluid (CSF) target NMDA receptors. Glial fibrillary acidic protein (GFAP) astrocytopathy is an autoimmune disease affecting the central nervous system (CNS). Meningoencephalitis can affect any anatomical region rostrocaudally, from the optic nerve to the spinal cord. The clinical implications of NMDAR antibodies overlapping with other antibodies against glial or neuronal cell surface proteins have not been investigated. Case presentation A 35-year-old male presented with headaches along with amnesia, slurred and awkward speech, psychiatric symptoms, cognitive decline, and insomnia. His medical history revealed ankylosing spondylitis for six months. Ancillary findings included CSF pleocytosis and elevated protein levels. T2-weighted fluid attenuation inversion recovery was used to image high-intensity lesions of the bilateral paraventricular, radiate corona, semioval centre, and right subcortical regions. The CSF was positive for NMDAR and GFAP antibodies through transfected cell-based assays. A diagnosis of anti-GFAP encephalitis was made, although the prominent clinical features were of anti-NMDAR encephalitis. Conclusions Herein, we describe a case of anti-NMDAR encephalitis with overlapping symptoms of GFAP antibody positivity. Patients with unusual symptoms of anti-NMDAR encephalitis should also be tested for anti-GFAP antibodies. However, because this was a single case study, caution should be exercised when interpreting the observations. Since the patient was diagnosed with autoimmune encephalitis, intravenous methylprednisolone was administered, which yielded a positive outcome.

In this paper, we consider the following critical fractional magnetic Choquard equation: ε2s(−Δ)A∕εsu+V(x)u=εα−N∫RN∣u(y)∣2s,α∗∣x−y∣αdy∣u∣2s,α∗−2u+εα−N∫RNF(y,∣u(y)∣2)∣x−y∣αdyf(x,∣u∣2)uinRN,\begin{array}{rcl}{\varepsilon }^{2s}{\left(-\Delta )}_{A/\varepsilon }^{s}u+V\left(x)u& =& {\varepsilon }^{\alpha -N}\left(\mathop{\displaystyle \int }\limits_{{{\mathbb{R}}}^{N}}\frac{| u(y){| }^{{2}_{s,\alpha }^{\ast }}}{| x-y\hspace{-0.25em}{| }^{\alpha }}{\rm{d}}y\right)| u\hspace{-0.25em}{| }^{{2}_{s,\alpha }^{\ast }-2}u\\ & & +{\varepsilon }^{\alpha -N}\left(\mathop{\displaystyle \int }\limits_{{{\mathbb{R}}}^{N}}\frac{F(y,| u(y){| }^{2})}{| x-y\hspace{-0.25em}{| }^{\alpha }}{\rm{d}}y\right)\hspace{0.08em}f\left(x,| u\hspace{-0.25em}{| }^{2})u\hspace{1em}{\rm{in}}\hspace{0.33em}{{\mathbb{R}}}^{N},\end{array} where ε>0\varepsilon \gt 0, s∈(0,1)s\in \left(0,1), α∈(0,N)\alpha \in \left(0,N), N>max{2μ+4s,2s+α∕2}N\gt {\rm{\max }}\left\{2\mu +4s,2s+\alpha /2\right\}, 2s,α∗=2N−αN−2s{2}_{s,\alpha }^{\ast }=\frac{2N-\alpha }{N-2s} is the upper critical exponent in the sense of Hardy-Littlewood-Sobolev inequality, (−Δ)As{\left(-\Delta )}_{A}^{s} stands for the fractional Laplacian with periodic magnetic field AA of C0,μ{C}^{0,\mu }-class with μ∈(0,1]\mu \in (0,1] and VV is a continuous potential and allows to be sign-changing. Under some mild assumptions imposed on VV and ff, we establish the existence of at least one ground state solution.

There are many unmeasurable branches along with distribution lines. The sensitivity and speed of traditional three-stage overcurrent protection lacks when applied to these lines. Even the phasor differential protection cannot identify internal faults sensitively to maintain sufficient safety under external faults. With 5G communication is penetrating the field of power grid automation, a comprehensive protection scheme for branched distribution lines is proposed. Firstly, analyze negative sequence currents phase characteristics under internal or external faults, and negative-sequence current phase-comparison protection is proposed. Secondly, in some harsh working conditions, 5G communication's synchronization cannot be guaranteed, or even out of step. A positive sequence amplitude differential protection is introduced. Finally, the three-stage overcurrent protection is combined to form a complete set of protection coordination schemes when communication interruption or some extreme situations. A 10 kV active distribution network model is built in PSCAD/EMTDC to verify the proposed protection criteria and scheme. The simulation results demonstrate the effectiveness of the proposed protection criteria and scheme.

In this paper, we study the dynamical effects of timely and delayed diagnosis on the spread of COVID-19 in Ghana during its initial phase by using reported data from March 12 to June 19, 2020. The estimated basic reproduction number, ℛ0, for the proposed model is 1.04. One of the main focus of this study is global stability results. Theoretically and numerically, we show that the disease persistence depends on ℛ0. We carry out a local and global sensitivity analysis. The local sensitivity analysis shows that the most positive sensitive parameter is the recruitment rate, followed by the relative transmissibility rate from the infectious with delayed diagnosis to the susceptible individuals. And that the most negative sensitive parameters are: self-quarantined, waiting time of the infectious for delayed diagnosis and the proportion of the infectious with timely diagnosis. The global sensitivity analysis using the partial rank correlation coefficient confirms the directional flow of the local sensitivity analysis. For public health benefit, our analysis suggests that, a reduction in the inflow of new individuals into the country or a reduction in the inter community inflow of individuals will reduce the basic reproduction number and thereby reduce the number of secondary infections (multiple peaks of the infection). Other recommendations for controlling the disease from the proposed model are provided in Section 7.

Compared with the traditional three-section current protection,the current differential protection can improve the protection performance as a whole in the active distribution network,but reduce the wide coverage of fibre channel . The 5G,with its advantages of high reliability,low latency and wide coverage,is expected to become a new communication scheme for differential protection in active distribution network. However,the 5G communication may still be affected by environmental interference and other factors,resulting in the missing of sampling data,which may affect the correct operation of the protection under the normal operation and external fault scenarios. To solve the above problems,firstly,combined with the plane method,the influences of various sampling data missing scenarios on the protection operation are analyzed qualitatively. Then,a strategy to reconstruct the missing sampling data by using order combination Neville interpolation method is proposed. Finally,an active distribution network simulation model is built in PSCAD,and the interpolation precisions of various interpolation methods are compared under a variety of missing sampling data scenarios,which verifies the effectiveness of the strategy proposed in this paper for improving the protection operation characteristics. Through theoretical calculation and analysis,it is concluded that the proposed strategy does not affect the real-time performance of protection in high-performance central processing unit (CPU).

Aiming at the problem that the current Quantum Random Number Generator (QRNG) cannot simultaneously meet the high-speed and real-time requirements of random number generation in quantum key distribution communication, this paper improves the QRNG scheme based on pulse laser as light source to extract phase information. The random phase information is converted into light intensity information by single-mode Michelson interferometer, and then converted into electrical signal by high-speed Photo Detector (PD). Finally, the real-time quantum random number generation rate of 1.1 Gbit/s is obtained by using 16 bit Analog-to-Digital Converter (ADC) with 250 MHz sampling rate and 50% extraction rate. A high-speed, real-time and integrated QRNG equipment is realized. At the same time, the advantages of this scheme and continuous laser as light source in principle and system design are compared. QRNG based on pulsed laser light source has passed various tests of China Academy of Information and Communications. The random number output by the product in the process of stable operation can pass 15 test standards specified in the State Cryptography Administration randomness test document GB/T 32915-2016 and National Institute of Standards and Technology (NIST) test standards.

Abstract Magnetic nanorobots (MNRs) based on paramagnetic nanoparticles/nanoclusters for the targeted therapeutics of anticancer drugs have been highlighted for their efficiency potential. Controlling the locomotion of the MNRs is a key challenge for effective delivery to the target legions. Here, we present a method for controlling paramagnetic nanoclusters through enhanced tumbling and disaggregation motions with a combination of rotating field and gradient field generated by external electromagnets. The mechanism is carried out via an electromagnetic actuation system capable of generating MNR motions with five degrees of freedom in a spherical workspace without singularity. The nanocluster swarm structures can successfully pass through channels to the target region where they can disaggregate. The results show significantly faster response and higher targeting rate by using rotating magnetic and gradient fields. The mean velocities of the enhanced tumbling motion are twice those of the conventional tumbling motion and approximately 130% higher than the gradient pulling motion. The effects of each fundamental factor on the locomotion are investigated for further MNR applications. The locomotion speed of the MNR could be predicted by the proposed mathematical model and agrees well with experimental results. The high access rate and disaggregation performance insights the potentials for targeted drug delivery application.

Abstract Acute ischemic stroke (AIS) is the most common type of stroke. Fingolimod is a sphingosine analog that acts on sphingosine‐1‐phosphate receptors (S1PR). Recently, the safety and efficacy of fingolimod in both patients with intracerebral hemorrhage and patients with AIS have been investigated in proof‐of‐concept trials. In this review, we performed a meta‐analysis to evaluate the efficacy and safety of fingolimod for AIS. This study was conducted according to the PRISMA (Preferred Reporting Items for Systemic review and Meta‐Analysis) statement. We searched for publications on the PubMed, Embase, Cochrane Central Register of Controlled Trials, Clinical trials, CNKI, Wanfang Data, VIP, CBM up to August 2021. We compiled five studies; a main meta‐analysis forest plots were conducted for the values of the proportion of patients whose modified Rankin scale (MRS) score was 0–1 at day 90. There were heterogeneities in each study; the method of sensitivity analysis was performed. A sensitivity analysis was performed with a mean difference (MD) of the efficacy of fingolimod plus standardized treatment versus standardized treatment alone. Random effect model is used for meta‐analysis regardless of the I2 index. The analysis was carried out for categorical variables using the risk ratio (RR), LogRR, and its 95% CI. The methodological quality of each randomized controlled trial (RCTs) was assessed according to the Cochrane Collaboration tool to assess the risk of bias (ROB). A meta‐analysis of five studies with 228 participants was conducted. The risk ratio of patients whose MRS score was 0–1 at day 90 between fingolimod plus standardized treatment and standardized treatment alone was 2.59 (95%CI, 1.48–4.56). The Fingolimod plus standard treatment group decreased infarct growth and improved clinical function than the standard treatment.

Abstract Background A few reports have shown that unilateral transverse process-pedicle percutaneous kyphoplasty is a good choice for patients with osteoporotic vertebral compression fracture (OVCF). However, this issue remains controversial and the related comprehensive research was lacked. Methods A retrospective study was conducted on patients receiving PKP surgery for OVCF. Patients were divided into three groups according to surgical approach. Symptom and radiographical evaluation were performed preoperatively, 1-month postoperatively, 1-year postoperatively and follow-ups. And follow-ups were repeated every year. Visual Analogue Scale Score (VAS), Oswestry Disability Index (ODI) scores, anterior vertebral height, coronal Cobb angle and sagittal Cobb angle was determined and compared among three groups. Results Totally 447 patients were included with an average age of 76.6 ± 7.2 years old. UTP showed significantly shorter surgical duration (p

A new magnetic damper is developed for the suspension and vibration isolation of precise instruments working in low-temperature and vacuum environments. The damper comprises permanent magnets, a non-magnetic conductor tube, and a spring, and a room-temperature prototype is designed in COMSOL Multiphysics and verified by experiments. A tubular eddy current damper is chosen because it has less leakage flux than the flat type and better usage of magnetic flux, which leads to higher eddy currents. The adjacent magnets arranged in the reverse direction of magnetization can contribute to obtaining a compact damper. COMSOL Multiphysics is proven to be effective software to predict the performance of an eddy current damper compared with the existing experimental and theoretical results. To apply the damper to low-temperature conditions, the selections of non-magnetic tubes and the permanent magnet are thoroughly analyzed. This study offers the applicability of the magnetic damper in the suspension and vibration isolation of precise instruments and provides suggestions for the design of low-temperature and vacuum magnetic dampers.

Micro-organisms are the main drivers of the water biogeochemical cycle and the major player in energy metabolism, which are pivotal processes for maintaining diversity and stability in ecological water systems. Aerobic anoxygenic phototrophic bacteria (AAPB), the important functional groups widespread in the water, can acquire energy from light and further affect the hydrochemical composition. The importance of AAPB is well recognized and has been studied extensively. In order to study the relationship between the hydrochemical characteristics and the AAPB feedback effect in front of the Wulixia Reservoir dam, water samples from different layers were collected. Based on the stable carbon isotope of dissolved organic carbon and particulate organic carbon isotope composition, the distribution pattern of AAPB was measured by real-time PCR technology. Results show that the hydrochemical type in the front of the reservoir dam water system was HCO3--Ca2+-Mg2+ type and had a poor-moderate eutrophication state during the sampling period. The results of dissolved oxygen, stable carbon isotope and the C/N showed that the main source of organic carbon was produced by micro-organisms. The ratio of AAPB to total planktonic bacteria in the Wulixia Reservoir water was 1.33%-1.60%, and the variation degree of AAPB abundance was greater than that of the total planktonic bacteria abundance, which means that the AAPB feedback is more sensitive to the hydrochemical characteristics compared with that of total planktonic bacteria. The canonical correspondence analysis reveals the relationship between hydrochemical composition and AAPB. Canonical correspondence analysis (CCA) results show that AAPB and total planktonic bacteria are strongly influenced by turbidity, which makes it possible to apply marine microbiological pump theory in karst reservoirs. Hydrochemical characteristic feedback on AAPB will improve understanding of the metabolic system of CO2-H2O-carbonate and micro-organisms.

Constructing multi-dimensional hierarchical superstructures has been, for a longtime, regarded as a promising strategy for modifying the physiochemical properties of nanomaterials. Guided by this rule, this work reports the synthesis of hierarchical superstructures of Ag-Ag2O-AgO nanoparticles (HSANs) using a convenient and surfactant-less photochemical method under 254 nm UV-irradiation. The formation of the HSANs superstructures is dominated by screw-dislocation-driven growth mechanism at low supersaturation condition. The structural evolution of the HSANs superstructures has been systematically investigated. The average size of the HSANs superstructures increased with prolonged 254 nm UV-irradiation. The step density on the superstructure surfaces also increased along with the 254 nm UV-irradiation time.

The collapse of the lead-zinc mine tailing dam in Sidi village (Yangshuo, Guangxi Zhuang Autonomous Region, and SW China) led to the spread of mining waste spills on the farmland along the river. Past reports concentrated on environmental pollution caused by metal mining process, and were less focused on the special pattern of heavy metal pollution caused by the dam collapse. Canonical correspondence analysis (CCA)was employed to reveal the relationship between heavy metal contamination and soil properties in different land use types around the polluted area. 12 soil samples from rice paddy fields, 12 from corn fields and 9 from citrus orchards were collected from the surface layer (0-20 cm) to analyze SOC, AN, AP, AK, CEC, C/N, pH, total and DTPA-extractable Pb, Zn, Cu, Cd. The results show that Pb-Zn mine tailing sand is a multi-mineral orebody of which Pb, Zn and Cd are the main pollutants and Cd is the environmental risk key factor controlling the soil quality. The spatial distribution pattern of Pb and Zn affected by land use type is more obvious. Moreover, from the arrow distribution of heavy metals, it can be seen that the heavy metal pollution was relatively more serious in the rice paddy fields than in the corn fields and citrus orchards. From the distance between the heavy metals arrow and the soil properties point, the combined pollution of Pb, Zn, Cu and Cd decreased CEC content and increased SOC concentration, but had only small effects on soil pH value and available nutrients (AN, AP, AK). There existed positive significant correlations between heavy metals and SOC.The SOC content in rice paddy fields was 18.14 g/kg, and had the significant statistical differences with other land use types. In summary, Pb-Zn tailing sands as the sustained release source of heavy metals have the consecutive inputting mechanism into the soil, which inhibited microbial communities' metabolism, resulting in carbon accumulation, and then influenced the carbon cycle in the area.

The linear zone of the S-curve, which is formed with the digital beamforming (DBF) method, is extremely narrow for monopulse angle measurements with distributed Multiple-Input and Multiple-Output (MIMO) radar. Based on the transmitting-receiving beam pattern without gratelobe, the DBF method is proposed to form the ΣΔ-beam by using the absolute value of the echo signal. The ideal null depth can be achieved and the linear zone of the S-curve is expanded because the main lobe of the Δ-beam is enveloped by the Σ-beam. The monopulse angle for a target with high angle velocity was estimated. When the Signal-to-Noise Ratio (SNR) was higher than -15 dB , the accuracy of the proposed method was better than that of conventional methods. When the SNR was equal to -15 dB , the accuracy of the proposed method was similar to conventional methods that use coherent integration before taking the absolute value of the echo signal.