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1.
Opt Express ; 32(7): 11715-11725, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571012

RESUMEN

The spin-orbit Hall effect (HE) is dominated by the law of conservation of angular momentum of a beam and is highly significant in light-matter interactions. The electromagnetic field, phase, topological structure, and spin-orbit HE of an azimuthally polarized vortex pulse beam in a tightly focused system are studied theoretically here. Calculations show that the focal field has ultrafast bright-dark alternating characteristics and a distorted phase distribution. Furthermore, the time evolution of the polarization singularity in the focused light field is explained using Stokes parameters. Importantly, the spin-orbit HE of the pulsed beam is shown to be time-varying in a tightly focused system. This time-varying spin-orbit HE is particularly sensitive to the pulse width and central wavelength. Our method has important applications in particle manipulation.

2.
Sensors (Basel) ; 24(12)2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38931503

RESUMEN

Space manipulators are expected to perform more challenging missions in on-orbit service (OOS) systems, but there are some unique characteristics that are not found on ground-based robots, such as dynamic coupling between space bases and manipulators, limited fuel supply, and working with unfixed bases. This paper focuses on trajectory-tracking control and internal force control for free-floating close-chain manipulators. First, the kinematics and dynamics of free-floating close-chain manipulators are given using the momentum conservation and spatial operator algebra (SOA) methodologies, respectively. Furthermore, an adaptive fuzzy integral sliding mode controller (AFISMC) based on time delay estimation (TDE) was designed for trajectory-tracking control, and a proportional-integral (PI) control strategy was adopted for internal force control. The global asymptotic stability of the proposed controller was proven by using the Lyapunov methodology. Three cases were conducted to verify the efficiency of the controller by using numerical simulations on two six-link manipulators with a free-floating base. The controller presents the desired tracking capability.

3.
Sensors (Basel) ; 23(6)2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-36991787

RESUMEN

This paper proposes a novel trajectory planning algorithm to design an end-effector motion profile along a specified path. An optimization model based on the whale optimization algorithm (WOA) is established for time-optimal asymmetrical S-curve velocity scheduling. Trajectories designed by end-effector limits may violate kinematic constraints due to the non-linear relationship between the operation and joint space of redundant manipulators. A constraints conversion approach is proposed to update end-effector limits. The path can be divided into segments at the minimum of the updated limitations. On each path segment, the jerk-limited S-shaped velocity profile is generated within the updated limitations. The proposed method aims to generate end-effector trajectory by kinematic constraints which are imposed on joints, resulting in efficient robot motion performance. The WOA-based asymmetrical S-curve velocity scheduling algorithm can be automatically adjusted for different path lengths and start/end velocities, allowing flexibility in finding the time-optimal solution under complex constraints. Simulations and experiments on a redundant manipulator prove the effect and superiority of the proposed method.

4.
Sensors (Basel) ; 23(22)2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-38005453

RESUMEN

This paper presents an interval type-2 fuzzy proportional-integral-derivative (IT2F-PID) controller that is designed using a new disassembled gradational optimization (D-GO) method. A PID controller is first optimized using the D-GO method and then connected to a type-1 fuzzy logic system (T1-FLS). The parameters of the T1-FLS are optimized, and the T1-FLS is blurred into the interval type-2 fuzzy logic system (IT2-FLS). Finally, the IT2F-PID controller is formed. The proposed method is compared with the concurrent and general optimization methods. The simulation results show that the D-GO method reduces the optimization time by over 90% compared with the general method, and decreases the integral-of-time-absolute-error (ITAE) by 30%. Beyond that, compared with the concurrent optimization method, the D-GO method reduces time by over 25%, and the ITAE value by about 95%. In the normal case, model uncertainty, target uncertainty, and external disturbance, the control ability of the IT2F-PID controller designed using the D-GO method is verified via simulations using a nonlinear forced closed-loop system. The results show that the overshoot is reduced by 80% and the fluctuation is reduced by 67% compared with a traditional PID controller and an IT2F-PID controller built using the general method.

5.
Opt Express ; 30(23): 41048-41060, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-36366590

RESUMEN

Optical linear and angular momenta have attracted tremendous research interest in recent years. In this paper we theoretically investigate the electromagnetic fields and linear and angular momentum properties of tightly focused radial- and azimuthal-variant vector input beams. Calculations show that a uniform 3D optical cage can be achieved when the optical degree of freedom of polarization in the radial direction is introduced. Furthermore, the distributions of linear and angular momenta in the focal volume are revealed. Moreover, we numerically investigate the gradient, scattering, and total forces as well as spin and orbital torques on a Rayleigh particle generated by the optical cage. It is found that there are two equilibrium positions before and after the focal plane, both of which can achieve stable 3D particles capture. Most importantly, the longitudinal spin and orbital torques show the same patterns but in opposite directions in the two equilibrium positions, thus, the unwinding of the double helix can be expected to be achieved by virtue of this special optical torque.

6.
Sensors (Basel) ; 22(18)2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-36146208

RESUMEN

In order to solve the tracking accuracy problem of the redundant manipulator, a PI control method with Henry gas solubility optimization parameter regulator (PI-HGSO) is proposed in this paper. This method consists of the controller and the parameter regulator. The characteristic is that the position deviation of a manipulator is equivalent to a specific function; namely, the proportional-integral (PI) controller is used to adjust the deviation input. The error can be better corrected by the processing of the PI controller so that the inverse kinematics solution of the minimum error can be realized. At the same time, the parameter selection of PI controllers has always been a difficulty in controller design. To address the problem, Henry gas solubility optimization (HGSO) is selected as a parameter regulator to optimize the parameters and obtain the optimal controller, thereby achieving high-precision trajectory tracking. Experiments on 9-DOF redundant manipulator show that our method achieves competitive tracking accuracy in contrast with others. Meanwhile, the efficiency and accuracy of the PI controller are greatly guaranteed by using HGSO to automatically optimize controller parameters instead of making approximate adjustments through infinite manual trial and error. Therefore, the feasibility and competitive superiority of PI-HGSO is fully proved in trajectory planning of redundant manipulators.


Asunto(s)
Solubilidad , Fenómenos Biomecánicos
7.
Eur J Clin Microbiol Infect Dis ; 40(7): 1559-1567, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33555444

RESUMEN

Patients with severe coronavirus disease in 2019 (COVID-19 pneumonia) may have many sequelae, which seriously affect their quality of life and work. Here, we report a case of infection in China, reviewed the course, treatment, and rehabilitation of a patient suffering from severe COVID-19 pneumonia, and collected his examination reports, including chest CT, laboratory examination results, lung function examination, sleep monitoring report, sex hormones, sperm morphology and activity. The patient's antiviral immunoglobulin G (IgG) continued to be positive for more than 11 months, and his small airway function was abnormal, and he suffered from respiratory problems (cough, chest pain, chest tightness, and shortness of breath), unstructured sleep apnea hypopnea syndrome, and nocturnal sleep hypoxemia. His abnormal sperm rate increased obviously, and sperm activity decreased obviously. Patients with severe COVID-19 pneumonia may have respiratory sequela, the abnormal sperm rate is obviously increased, and IgG positive can last for a long time.


Asunto(s)
COVID-19/complicaciones , Inmunoglobulina G/inmunología , Trastornos Respiratorios/etiología , Espermatozoides/patología , Adulto , COVID-19/patología , COVID-19/fisiopatología , Enfermedad Crítica , Humanos , Masculino , SARS-CoV-2/inmunología , Apnea Obstructiva del Sueño/etiología , Síndrome Post Agudo de COVID-19
8.
Acta Trop ; 249: 107046, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37866727

RESUMEN

Hemorrhagic fever with renal syndrome (HFRS) is a significant public health problem in Hubei Province, China, where a novel strain of orthohantavirus, HV004, was reported in 2012. However, no systematic study has investigated the prevalence and variation of orthohantavirus in rodents and humans. Herein, 2137 small mammals were collected from ten HFRS epidemic areas in Hubei Province from 2012 to 2022, and 143 serum samples from patients with suspected hemorrhagic fever were collected from two hospitals from 2017 to 2021. Orthohantavirus RNA was recovered from 134 lung tissue samples from five rodent species, with a 6.27 % prevalence, and orthohantavirus was detected in serum samples from 25 patients. Genetic analyses revealed that orthohantavirus hantanense (HTNV), orthohantavirus seoulense (SEOV), and orthohantavirus dabieshanense (DBSV) are co-circulating in rodents in Hubei, and HTNV and SEOV were identified in patient serum. Phylogenetic analysis showed that most of the HTNV sequences were clustered with HV004, indicating that HV004-like orthohantavirus was the main HNTV subtype in rodents. Two genetic reassortments and six recombination events were observed in Hubei orthohantaviruses. In summary, this study identified the diversity of orthohantaviruses circulating in Hubei over the past decade, with the HV004-like subtype being the main genotype in rodents and patients. These findings highlight the need for continued attention and focus on orthohantaviruses, especially concerning newly identified strains.


Asunto(s)
Fiebre Hemorrágica con Síndrome Renal , Orthohantavirus , Virus ARN , Animales , Humanos , Fiebre Hemorrágica con Síndrome Renal/epidemiología , Filogenia , Orthohantavirus/genética , Roedores , China/epidemiología
9.
ACS Appl Mater Interfaces ; 15(17): 20753-20760, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37074082

RESUMEN

A conventional pulse oximeter system is composed of two light sources with different peak emission wavelengths and a photodetector. Integrating these three independent components into one single device will absolutely simplify the system design and create a miniaturized size of the product. Here, we demonstrate a bilayer perovskite-CdSe quantum dot (hereafter perovskite-QD) diode capable of voltage-tunable green/red emission and photodetection. The proposed diode also presents an intriguing feature of simultaneous light emission and detection, which is explored as regards the diode being used as a photoconductor when the positive bias is larger than the built-in voltage. The multifunctional and multicolor diode is further employed in a reflective pulse oximeter system, as either the multicolor light sources or the sensing unit in the system provide accepted and trustful results for heart rate and arterial blood oxygenation. Our work provides a possible avenue for the simplification of the pulse oximetry with a compact and miniaturized design in the future.

10.
Front Bioeng Biotechnol ; 9: 809443, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35223817

RESUMEN

The treatment of inner ear disorders always remains a challenge for researchers. The presence of various physiological barriers, primarily the blood-labyrinth barrier (BLB), limits the accessibility of the inner ear and hinders the efficacy of various drug therapies. Yet despite recent advances in the cochlea for repair and regeneration, there are currently no pharmacological or biological interventions for hearing loss. Current research focuses on the localized drug-, gene-, and cell-based therapies. Drug delivery based on nanotechnology represents an innovative strategy to improve inner ear treatments. Materials with specific nanostructures not only exhibit a unique ability to encapsulate and transport therapeutics to the inner ear but also endow specific targeting properties to auditory hair cells as well as the stabilization and sustained drug release. Along with this, some alternative routes, like intratympanic drug delivery, can also offer a better means to access the inner ear without exposure to the BLB. This review discusses a variety of nano-based drug delivery systems to the ear for treating inner ear diseases. The main factors affecting the curative efficacy of nanomaterials are also discussed. With a deeper understanding of the link between these crucial factors and the clinical effect of nanomaterials, it paves the way for the optimization of the therapeutic activity of nanocarriers.

12.
Bioresour Technol ; 317: 124001, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32805483

RESUMEN

An anaerobic membrane bioreactor (AnMBR) was used to treat low to high (5-200 mg/L) concentrations of 2-chlorophenol (2-CP) wastewater. The AnMBR achieved high and stable chemical oxygen demand removal and 2-CP removal with an average value of 93.2% and 94.2% under long hydraulic retention times (HRTs, 48-96 h), respectively. 2-CP removal efficiency of 98.6 mg/L/d was achieved with 2-CP concentration of 200 mg/L, which was much higher than that of other anaerobic bioreactors. Furthermore, volatile fatty acids didn't accumulate under high 2-CP loading. Long HRTs significantly reduced the membrane fouling as the fouling rate (0.90 × 109-5.44 × 109 m-1h-1) was low. Spirochaetaceae and Methanosaeta were the dominant microbes responsible for dechlorination, methanogenesis, and shock resistance. All these results demonstrate that this AnMBR operated under long HRTs is good and robust for fluctuating chlorophenols wastewater treatment, which has high potential for treating fluctuating refractory organics wastewater with the low membrane fouling rate.


Asunto(s)
Clorofenoles , Microbiota , Anaerobiosis , Reactores Biológicos , Membranas Artificiales , Eliminación de Residuos Líquidos , Aguas Residuales
13.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 32(12): 1428-1433, 2020 Dec.
Artículo en Zh | MEDLINE | ID: mdl-33541492

RESUMEN

OBJECTIVE: To analyze the clinical and laboratory characteristics of coronavirus disease 2019 (COVID-19) patients with different prognosis, and to provide evidence for the diagnosis and treatment of COVID-19. METHODS: The clinical and laboratory characteristics of 215 cases of confirmed COVID-19 patients admitted in the First People's Hospital of Tianmen City from January 18 to March 10, 2020 were retrospectively analyzed, including blood cell indexes, inflammatory indexes [C-reactive protein (CRP) and procalcitonin (PCT)], liver function, cardiac function, renal function, blood coagulation function, electrolyte, chest CT scan, and 2019 novel coronavirus (2019-nCoV) nucleic acid tests. The differences of above indexes in the two groups were compared and analyzed. In addition, 55 patients with other viral pneumonia were selected as the control group who admitted to the hospital from August 1 to November 30, 2019. The changes of laboratory indexes of COVID-19 group and control group were observed. RESULTS: In the 215 patients, 206 patients survived and 9 patients died. The average age of survival group was significantly lower than that in the death group, and the average length of hospital stay was significantly longer than the death group. (1) Clinical features: the proportion of underlying diseases in the death group was significantly higher than that in the survival group, such as dyspnea, sore throat, shiver, hypertension, diabetes, coronary heart disease, renal disease, and surgical history. There were no significant differences in other symptoms, signs and underlying diseases between the two group. (2) Laboratory test indexes of the two groups: in death group, white blood cell count [WBC (×109/L): 10.6 (4.0, 13.4) vs. 4.90 (3.92, 6.26)], neutrophils count [NEU (×109/L): 9.7 (3.4, 12.2) vs. 2.9 (2.1, 4.2)]; ratio of neutrophils to lymphocytes [NLR: 14.66 (5.19, 18.48) vs. 2.34 (1.47, 3.34)], CRP [mg/L: 130.21 (35.74, 210.86) vs. 17.90 (3.11, 50.23)], PCT [mg/L: 1.46 (0.45, 13.12) vs. 0.04 (0.02, 0.07)], lactate dehydrogenase [LDH (µmol×s-1×L-1): 4.80 (3.34, 7.37) vs. 3.77 (2.99, 5.12)], creatinine [Cr (µmol/L): 72.9 (69.6, 627.5) vs. 68.4 (55.5, 81.9)], D-dimer [mg/L: 0.86 (0.56, 3.32) vs. 0.39 (0.33, 0.58)], the area of ground glass opacity of chest CT scan [77.8% (7/9) vs. 35.0% (72/206)], the area of local patchy shadows [55.6% (5/9) vs. 17.5% (36/206)], the area of bilateral patchy shadows [100.0% (9/9) vs. 49.5% (102/206)] were significantly higher than those in survival group (all P < 0.01), lymphocyte count [LYM (×109/L): 0.6 (0.5, 0.8) vs. 1.3 (1.0, 1.6)], Na+ [mmol/L: 136.1 (131.0, 136.8) vs. 138.8 (136.5, 140.4)], Cl- [mmol/L: 97.7 (92.7, 100.9) vs. 102.7 (100.2, 104.3)], and carbon dioxide [CO2 (mmol/L): 23.0 (20.6, 28.5) vs. 29.2 (27.7, 30.9)] were significantly lower than those in survival group (all P < 0.05). (3) Laboratory test indicators in COVID-19 and control groups: in COVID-19 group, WBC, NEU, LYM, platelet count (PLT), coefficient of variation of red blood cell distribution width (RDW-CV), standard deviation of red blood cell distribution width (RDW-SD) and Cl- were significantly lower than those in control group, NLR, CRP, K+ and CO2 were significantly higher than those in control group. CONCLUSIONS: The major early symptoms of COVID-19 are fever, cough, chest tightness and fatigue. Age and underlying disease may be the risk factors which affect the prognosis of patients with COVID-19. The laboratory indexes such as WBC, NEU, LYM, CRP, PCT, LDH and Cr between death group and survival group were significantly abnormal in the early stages of COVID-19, which would have important implications for the prognosis of patients with COVID-19. Meanwhile, laboratory test indexes, including WBC, NEU, LYM, PLT, RDW-CV, RDW-SD, CRP, Cl-, K+ and CO2, also have important value in the differential diagnosis between COVID-19 and other viral pneumonia.


Asunto(s)
COVID-19 , Humanos , Laboratorios , Pronóstico , Curva ROC , Estudios Retrospectivos , SARS-CoV-2
14.
J Med Chem ; 63(22): 13899-13912, 2020 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-33141588

RESUMEN

Bioorthogonal decaging reactions for controllable drug activation within complex biological systems are highly desirable yet extremely challenging. Herein, we find a new class of Pt(II)-triggered bioorthogonal cleavage reactions in which Pt(II) but not Pt(IV) complexes effectively trigger the cleavage of O/N-propargyl in a variety of ranges of caged molecules under biocompatible conditions. Based on these findings, we propose a general strategy for integrated bioorthogonal prodrugs and accordingly design a prodrug 16, in which a Pt(IV) moiety is covalently connected with an O2-propargyl diazeniumdiolate moiety. It is found that 16 can be specifically reduced by cytoplasmic reductants in human ovarian cancer cells to liberate cisplatin, which subsequently stimulates the cleavage of O2-propargyl to release large amounts of NO in situ, thus generating synergistic and potent tumor suppression activity in vivo. Therefore, Pt(II)-triggered depropargylation and the integration concept might provide a general strategy for broad applicability of bioorthogonal cleavage chemistry in vivo.


Asunto(s)
Activación Metabólica/efectos de los fármacos , Antineoplásicos/farmacología , Cisplatino/química , Modelos Animales de Enfermedad , Embrión no Mamífero/efectos de los fármacos , Neoplasias Ováricas/tratamiento farmacológico , Profármacos/farmacología , Animales , Embrión no Mamífero/citología , Femenino , Humanos , Neoplasias Ováricas/patología , Células Tumorales Cultivadas , Pez Cebra
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 70(5): 1146-51, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18155640

RESUMEN

Near-infrared (NIR) spectroscopy, in combination with chemometrics, enables nondestructive analysis of solid samples without time-consuming sample preparation methods. A new method for the nondestructive determination of compound amoxicillin powder drug via NIR spectroscopy combined with an improved neural network model based on principal component analysis (PCA) and radial basis function (RBF) neural networks is investigated. The PCA technique is applied to extraction relevant features from lots of spectra data in order to reduce the input variables of the RBF neural networks. Various optimum principal component analysis--radial basis function (PCA-RBF) network models based on conventional spectra and preprocessing spectra (standard normal variate (SNV) and multiplicative scatter correction (MSC)) have been established and compared. Principal component regression (PCR) and partial least squares (PLS) multivariate calibrations are also used, which are compared with PCA-RBF neural networks. Experiment results show that the proposed PCA-RBF method is more efficient than PCR and PLS multivariate calibrations. And the PCA-RBF approach with SNV preprocessing spectra is found to provide the best performance.


Asunto(s)
Amoxicilina/química , Calibración , Modelos Químicos , Modelos Moleculares , Polvos , Espectroscopía Infrarroja Corta
16.
J Colloid Interface Sci ; 509: 522-528, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-28967382

RESUMEN

Hydrophilic medium and precursors were used to synthesize a hydrophilic electro-catalyst for overall water splitting. The cobalt sulfide (Co3S4) catalyst exhibits a layered nanosheet structure with a hydrophilic surface, which can facilitate the diffusion of aqueous substrates into the electrode pores and towards the active sites. The Co3S4 catalyst shows excellent bifunctional catalytic activity for both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in alkaline solution. The assembled water electrolyzer based on Co3S4 exhibits better performance and stability than that of Pt/C-RuO2 catalyst. Thereforce the hydrophilic Co3S4 is a highly promising bifunctional catalyst for the overall water splitting reaction.

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