Numerical Simulation and Experimental Investigation on Performance of the Wells Turbine in Irregular Oscillating Flow

The Wells turbine is an axial-flow air-turbine designed to extract energy from ocean waves. An important consideration is the self-starting capability of the Wells turbine, a phenomenon encountered where the turbine accelerate by itself up to a certain speed for the best turbine performance. In order to clarify the self-starting characteristic and running performance of the Wells turbine in an irregular oscillating flow, a numerical simulation process is established in this paper on the rational assumption of quasi-steady flow conditions, Both self-starting characteristics and running performance are obtained through the numerical simulation and subsequently compared with the experimental data achieved on a computer-controlled oscillating flow test rig which could realize some irregular oscillating flow according to the specified spectrum. Results show that the self-starting time decreases with the increase of the significant wave height and the mean frequency of the irregular oscillating flow, Therefore, it is possible to predict accurately the performance of the Wells turbine by computer simulation.

A Novel Trajectory Tracking Control of AGV Based on Udwadia-Kalaba Approach

Dear Editor,This letter is about an automated guided vehicle(AGV)trajectory tracking control method based on Udwadia-Kalaba(U-K)approach.This method provides a novel,concise and explicit motion equation for constrained mechanical systems with holonomic and/or nonholonomic constraints as well as constraints that may be ideal or nonideal.In this letter.

Research on the comprehensive performance of PrFeB magnets for synchrotron radiation and free electron laser

PrFeB magnets, which possess excellent magnetic properties at low temperatures, have important application value as cryogenic permanent magnet undulators for synchrotron radiation sources and free electron lasers. In this research study, several high-performance PrFeB magnets(P42H, P48SH, and P48UH) were prepared, and their performance was comprehensively examined, including evaluations of their magnetic properties,microstructures, uniformity, and stability. Next,their application prospects were analyzed and discussed. In China, the first cryogenic permanent magnet undulators(CPMUs) with P48SH magnets with 18 mm cycle lengths have been developed. When the temperature is 80 K and the gap is 6.0 mm,the magnetic field measurement results of the CPMU showed that the effective magnetic field peak was approximately 0.92 T, yielding an increase of 11.76% relative to operation at 300 K, with an RMS phase error of about 4.99°.

Challenges and improvement in management of neonates born to mothers with COVID-19 in China

Objective:China was the first country suffering from the SARS-CoV-2 pandemic and one of the countries with stringent mother-neonate isolation measure implemented.Now increasing evidence suggests that coronavirus disease 2019(COVID-19)should not be taken as an indication for formula feeding or isolation of the infant from the mother.Methods:We conducted a retrospective cohort study in 44 hospitals from 14 provinces in China to investigate the management of neonates whose mothers have confirmed or suspected COVID-19.In addition,65 members of Chinese Neonatologist Association(CNA)were invited to give their comments and suggestions on the clinical management guidelines for high-risk neonates.Results:There were 121 neonates born to 118 mothers suspected with COVID-19 including 42 mothers with SARS-CoV-2 positive results and 76 mothers with SARS-CoV-2 negative results.All neonates were born by caesarean section,isolated from their mothers immediately after birth and were formula-fed.Five neonates were positive for SARSCoV-2 at initial testing between 36 and 46 h after birth.Regarding the confusion on the clinical management guidelines,58.78%of the newborns were put into isolation,32.22%were subject to PCR tests,and 5.16%and 2.75%received breastfeeding and vaccination,respectively.Conclusion:The clinical symptoms of neonates born to mothers with confirmed SARS-CoV-2 were mild,though five neonates might have been infected in utero or during delivery.Given the favorable outcomes of neonates born to COVID-confirmed mothers,full isolation may not be warranted.Rather,separation of the mother and her newborn should be assessed on a case-by-case basis,considering local facilities and risk factors for adverse outcomes,such as prematurity and fetal distress.

Mitotic phosphorylation of PRC1 at Thr470 is required for PRC1 oligomerization and proper central spindle organization

在细胞分裂期间，染色体分离被和着丝点的锭子微导管的相互作用安排。进在分开的染色单体之间的一支组织中央锭子的 interpolarmicrotubules 的戏剧的改变为胞质分裂的开始和实行被要求。中央锭子组织要求有丝分裂的 kinesins， chromosomal 旅客蛋白质建筑群，和微导管捆绑蛋白质 PRC1。由在 Thr470 和 Thr481 的 Cdc2 的 PRC1 isphosphorylated 在有丝分裂期间。然而，在 Thr470 的功能的关联 ofPRC1 磷酸化留下了逃犯。这里，我们证明 thenon-phosphorylatable 异种 PRC1 (T470A ) 然而并非 phospho-mimicking 异种 PRC1 (T470E ) 的那表情引起中央锭子的异常组织。Immunoprecipitation 实验与野类型的 PRC1 显示那 bothPRC1 (T470A ) 和 PRC1 (T470E ) 突变蛋白质伙伴，建议 Thr470 的 thatphosphorylation 不改变 PRC1 自我协会。另外，在 vitroco 沉积，实验证明 PRC1 绑在独立于 Thr470 的 phosphorylationstate 的微导管。胶化过滤实验建议了 PRC1 的 Thr470 promotesoligomerization 的那磷酸化。给 Thr470 磷酸化的那预防禁止 PRC1oligomerization 试管内并且引起中央锭子体内的一个异常组织的事实，我们建议这 phosphorylation 依赖的 PRC1 oligomerization 保证中央锭子汇编在房间周期发生在适当时间。

Rate constants for the reaction of hydroxyl radicals with HFC-134a

Rate constants for the reaction of hydroxyl radicals with HFC 134a (CH 2FCF 3) have been measured by the discharge flow resonance fluorescence (DF RF) technique over the temperature range 288—370 K. The derived Arrhenius equation is: k″ =(1.27±0.16)×10 -12 exp(-(1662±41)/ T )cm 3/(mol·s). The tropospheric lifetime of HFC 134a is estimated to be 10.5 years, which is in excellent agreement with the most recent results.

THE ASSOCIATION OF LIVING POLYSTYRYLLITHIUM IN BENZENE

The effects of the chain length, active end group and concentration on the association of living polystyryllithium (PS(-)Li(+)) chains in benzene were examined by a combination of static and dynamic laser light scattering in a cuvette equipped with a high-vacuum stopcock. The results show that long PS(-)Li(+) chains (M(w) > 1 x 10(4)) usually form dimers in the solution. In contrast, shorter PS(-)Li(+) chains exhibit two relaxation modes, where the fast mode is related to the translational diffusion of the living chain dimers. The end capping of the living chain with bulky 1,1-diphenylethene (DPE) leads to an intensity increase of the slow mode, indicating that the slow mode is not due to the chain aggregates but to temporal aggregates or long-range density fluctuation induced by weak electrostatic dipole-dipole interaction between ionic pairs at the chain ends.

THE OBSERVATION OF INTERNAL MOTION OF LINEAR POLYSTYRENE CHAINS IN CYCLOHEXANE AROUND 0 TEMPERATURE

A high molecular weight （M;=1.85×10;） polystyrene （PS） with narrow distribution was prepared by high vacuum anionic polymerization in tetrahydrofuran.By use of dynamic light scattering,the dynamics of PS chains in cyclohexane was studied around theθtemperature.For the first time,we have observed the internal motion of polymer chains in solutions below theθtemperature by using dynamic light scattering at smaller angles （even qR;<1）.

DEFECTS AND THEIR THERMAL ANNEALING BEHAVIOURS IN n-Si IMPLANTED WITH BORON AND PHOSPHORUS

An up to date most detailed information of H(Hole)as well as E(Electron)traps produced by low dose(10^(11)cm^(-2))boron and phosphorus implantation in n-Si and their thermal annealing behaviours are reported.For the first time,two hole traps H2(0.62),H3(0.49)of huge concentrations were detected in B^(+)implanted n-Si.They are tentatively assigned as boron related acceptors.H2(0.51)of huge concentration were detected in P^(+)implanted n-Si.Other three hole traps H1(0.63),H4(0.37)and H5(0.15)were detected in both B^(+)and P^(+)implanted n-Si;they are thus unrelated to boron.E traps are also reported;some of these E traps are consistent with previous reports and some are new.

The Pattern of Neurological Disorders;Revisited Prevalence Data of a Dedicated Neurology Clinic in Sudan

Background: The diverse modes in geographical locations, environmental factors, genetic and racial characteristics play a complex role in determining the pattern of neurological disorders worldwide. Determining the pattern of neurological disorders enables health policymakers to plan evidently for service, training, and research priorities. Few prevalence studies in neurology were conducted in Sudan. Methods: This is a retrospective hospital-based study that reviewed the medical records of patients who attended a Dedicated Neurology Clinic (DNC) in Omdurman, the national Capital of Sudan, for 24 months, from January 2016 to January 2018. This study aimed to determine the DNC pattern of neurological disorders as a representative subset prevalence in Sudan. Neurologists conducted the medical workup for diagnosis after at least two visits. All patients have ethically consented. Results: The total number of patients was 1050. Only 749 patients (71.3%) fulfilled the inclusion criteria. The mean age was 46.5 ± 1.9, and males were 45.3%. 72% were from the Capital. The presenting symptoms were headache (16.6%), seizures (11.5%), limbs weakness (11.2%), and lower percentages for other neurological symptoms. The commonest diagnoses were Stroke 12.4%, Epilepsy 9.3%, Primary Headache 8.8%, Movement Disorders 7.3%, Peripheral Neuropathy 6%, Dementia 4% Neuroinfections 1.4%, Demyelinating Disorders 2.6%, Spinal Spondylotic Radiculopathy 2.6% and 1.7% for Cerebral Venous Thrombosis. Conclusion: The data from Sudan-DNC showed that the most common neurological disorders descendingly were Stroke, Epilepsy, Headache, Movement Disorders, Peripheral Neuropathy, Dementia, Infections, Demyelinating Disorders, Spinal Spondylotic Radiculopathy, and Cerebral Venous Thrombosis. The demyelinating disorders and peripheral neuropathy showed a higher percentage than our previous preliminary prevalence study in 2012 compared to the other conditions, which showed similar rates in that study.

NeuroBiometric:An Eye Blink Based Biometric Authentication System Using an Event-Based Neuromorphic Vision Sensor

The rise of the Internet and identity authentication systems has brought convenience to people's lives but has also introduced the potential risk of privacy leaks.Existing biometric authentication systems based on explicit and static features bear the risk of being attacked by mimicked data.This work proposes a highly efficient biometric authentication system based on transient eye blink signals that are precisely captured by a neuromorphic vision sensor with microsecond-level temporal resolution.The neuromorphic vision sensor only transmits the local pixel-level changes induced by the eye blinks when they occur,which leads to advantageous characteristics such as an ultra-low latency response.We first propose a set of effective biometric features describing the motion,speed,energy and frequency signal of eye blinks based on the microsecond temporal resolution of event densities.We then train the ensemble model and non-ensemble model with our Neuro Biometric dataset for biometrics authentication.The experiments show that our system is able to identify and verify the subjects with the ensemble model at an accuracy of 0.948 and with the non-ensemble model at an accuracy of 0.925.The low false positive rates(about 0.002)and the highly dynamic features are not only hard to reproduce but also avoid recording visible characteristics of a user's appearance.The proposed system sheds light on a new path towards safer authentication using neuromorphic vision sensors.

Applications of Error Propagation Analyses to Geochemical Calculation

Two examples are given for comparing applications and limitations of four methods which can be used to deal with error propagation in geochemical calculations.The examples indicate that the Monte Carlo method can also be employed to evaluate the effect of covariance.A special function of the method for covariance matrix shown here can reveal the correlations of middle variables relative to the independent primary variables.

Treatment of Waste Tyre Powder Using a High-frequency Capacitively Coupled Plasma Reactor

A high-frequency (HF) capacitively coupled plasma reactor was developed to study the pyrolysis of waste tyre powder. The main objective was to generate a plasma at medium pressure and moderate temperatures for waste tyre powder gasification. Description of the reactor setup and experimental results concerning the plasma characteristics and product gas composition were presented, and potential use of the pyrolytic char was also discussed. Plasma temperatures were found to be between 1073 K to 1773 K, and under optimum operating conditions, over 70% of the tyre feed was converted into gaseous products by the treatment process. Pyrolysed gas was a mixture of H2, CO, CH4 and other organic compounds. The pyrolytic char may be used as low cost activated carbon for treating the species with large molecular weight.

DIFFUSION OF LONG CHAINS THROUGH A POROUS THIN GEL NETWORK

Using a core （142 nm） made of linear polystyrene （PS） chains as a seed, we further polymerized a thin layer of cross-linked PS shell （7 nm） on it in water to form a core-shell particle. Such a particle swells in toluene, which enables linear PS chains inside the core to gradually diffuse out through the porous shell. Using a combination of static and dynamic laser light scattering, we examined the chain diffusion process by following the change of the scattering intensity （i.e. the average molar mass of the particles）. For the first time, we have revealed that the diffusion exhibits three stages. In the first stage, the chain diffusion through the shell is even faster than their translational diffusion in a dilute solution. The three stages respectively correspond to the change of the solution in the core from concentrated to semidilute and then from semidilute to dilute.

Hot-Drawing of Ultrahigh-Molecular-Weight Polyethylene Gel Films

The three stages in the hot-drawing process of ultrahigh-molecular-weight polyethylene gel films can be detected by x-ray diffraction, infrared spectroscopy, birefringence and scanning electron microscopy. In the first stage of the drawing process, the lamellae in the gel films rotate and/or slip with the b-axis preferentially perpendicular to the drawing direction. With increased drawing, the c-axis of the lamellae become parallel to the stretching direction while unfolding of the chain begins, and the chains of the amorphous phase also orient along the drawing direction in the strain-chain domain. When the draw ratio is large enough, the lamellar structure is transformed into a fibrillar structure in a two-dimensional fashion.

MULTI-HOP RELAYING IN 5G： FROM RESEARCH TO SYSTEMS, STANDARDS, AND APPLICATIONS

In recent years,the demands of high traffic transmission motivate the rapid development of wireless access techniques,and it becomes promising to design the fifth generation(5G)wireless networks.Essential requirements for 5G involve higher traffic volume,indoor or hotspot traffic,and spectrum,energy,and cost efficien-

Profile function properties & optical transition formulae

Profile function properties with different variables are discussed, the formulae of stimulated absorption, spontaneous and stimulated emission, absorption and emission coefficients, and cross sections are deduced, and some confusing issues are clarified.

Insulin requirement profiles and related factors of insulin pump therapy in patients with type 2 diabetes

Continuous subcutaneous insulin infusion(CSII)is an effective therapy to control hyperglycemia in both patients with type 1 diabetes and type 2 diabetes.However,there is little data investigating the insulin dose setting during CSII therapy in type 2 diabetes to achieve optimal glycemic control and avoid the risk of hypoglycemia.Thus,this study is aimed to assess the dose characteristics of insulin requirement and explore the related clinical factors in patients with type 2 diabetes who were treated with CSII.A total of 327 patients(195 males)aged 52.9±12.5 years old were included in this study.Patients were treated with CSII to achieve the target fasting capillary blood glucose(4.4-7.0 mmol L^(-1))and 2-h postprandial capillary blood glucose(4.4-10.0 mmol L^(-1))by adjusting insulin infusion according to the seven-point capillary blood glucose profiles.Total daily insulin dose(TDD),total daily insulin dose per kilogram(TDD kg-1)and the ratio of total basal insulin dose(TBD)to TDD(%TBa)were calculated after patients achieved the glucose targets for at least 3 days via 1-2 weeks of CSII treatment.And insulin dose,insulin dosing patterns and the relevant clinical factors were analyzed.The mean ratio of basal/bolus insulin distribution of all patients was 40%:60%.Patients with central obesity needed more TDD(51.3±17.1 U versus 43.5±14.0 U,P<0.05)and TDD kg^(-1)(0.8±0.3 U kg^(-1)versus 0.7±0.2 U kg^(-1),P<0.05)than those without central obesity.Pearson's correlation analysis demonstrated that TDD was positively correlated with body mass index(BMI),waist circumference(WC),baseline fasting plasma glucose(FPG),fasting C-peptide level,2 h-postprandial C-peptide level and time to achieve glycemic target(all P<0.05);TDD kg^(-1)was positively correlated with waist-to-hip ratio(WHR),baseline FPG,glycosylated hemoglobin Ale(HbAlc),fasting C-peptide level and time to achieve glycemic target,and negatively correlated with BMI(all P<0.05).Multiple linear regression analyses revealed that BMI(β=1.796,P<0.01),WC(β=0.109,P<0.01),baseline FPG(β=1.459,P<0.01)and HbAlc(β=0.930,P=0.021)were independently related to TDD.Gender(β=-0.107,P=0.003),WC(β=0.005,P=0.029),baseline FPG(β=0.025,P<0.01)and HbAlc(β=0.016,β=0.007)were independently associated with TDD kg^(-1).Gender(β=-0.015,P=0.048)and disease duration(β=0.134,P=0.029)were independently associated with%TBa.%TBa is around 40%in Chinese patients with type 2 diabetes treated with CSII when glycemic control is achieved.In addition to body weight or BMI,WC and glucose levels before CSII should be considered to set TDD.Patients with central obesity or poor glycemic control might need more TDD.Higher%TBa should be considered in female patients or patients with longer disease duration.

Thermoelectric properties of In-Hg co-doping in SnTe:Energy band engineering

Synergistic effect of band convergence and resonant level could be manipulated in SnTe by co-doping In and Hg,leading to a potential thermoelectric performance enhancement in a much wider temperature range.In this work we carefully investigated thermoelectric properties of the In-Hg co-doped SnTe,synthesized by a hot pressing method.With this co-doping the Seebeck coefficients of the co-doped samples were greatly improved(over 50 mVK^(-1))at the room temperature.Although power factors of the In-Hg co-doped SnTe were also able to be optimized,the peak ZT(0.9 at 850 K in Sn_(0.98)Bi_(0.02)Te-1%HgInTe_(2)),however,is not high enough when comparing to other co-doped SnTe systems.This may be caused by the relatively high lattice thermal conductivity.An apparent competition between band convergence doping and resonant level doping was observed in our experiment.The results suggest that band engineering via co-doping should be further understood in order to optimize the thermoelectric properties inside the material system.

Efficacy,safety and pharmacokinetics of Unecritinib(TQ-B3101)for patients with ROS1 positive advanced non-small cell lung cancer:a Phase I/II Trial

This phase I/II trial characterized the tolerability,safety,and antitumor activities of unecritinib,a novel derivative of crizotinib and a multi-tyrosine kinase inhibitor targeting ROS1,ALK,and c-MET,in advanced tumors and ROS1 inhibitor-naive advanced or metastatic non-small cell lung cancer(NSCLC)harboring ROS1 rearrangements.Eligible patients received unecritinib 100,200.