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1.
Front Neurorobot ; 16: 843267, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35574228

RESUMO

Multifingered robotic hands (usually referred to as dexterous hands) are designed to achieve human-level or human-like manipulations for robots or as prostheses for the disabled. The research dates back 30 years ago, yet, there remain great challenges to effectively design and control them due to their high dimensionality of configuration, frequently switched interaction modes, and various task generalization requirements. This article aims to give a brief overview of multifingered robotic manipulation from three aspects: a) the biological results, b) the structural evolvements, and c) the learning methods, and discuss potential future directions. First, we investigate the structure and principle of hand-centered visual sensing, tactile sensing, and motor control and related behavioral results. Then, we review several typical multifingered dexterous hands from task scenarios, actuation mechanisms, and in-hand sensors points. Third, we report the recent progress of various learning-based multifingered manipulation methods, including but not limited to reinforcement learning, imitation learning, and other sub-class methods. The article concludes with open issues and our thoughts on future directions.

2.
Artigo em Inglês | MEDLINE | ID: mdl-26571092

RESUMO

Tau-fluvalinate (TFL) and flumethrin (FL), widely used in agriculture and a class of synthetic pyrethroid pesticides with a similar structure, may cause a potential security risk. Herein, the modes of binding in vitro of TFL and FL with calf thymus DNA (ctDNA) were characterized by fluorescence, UV-vis absorption, circular dichroism (CD) and Fourier transform infrared (FT-IR) spectroscopy with the aid of viscosity measurements, melting analyses and molecular docking studies. The fluorescence titration indicated that both TFL and FL bound to ctDNA forming complexes through hydrogen bonding and van der Waals forces. The binding constants of TFL and FL with ctDNA were in the range of 10(4)Lmol(-1), and FL exhibited a higher binding propensity than TFL. The iodide quenching effect, single/double-stranded DNA effects, and ctDNA melting and viscosity measurements demonstrated that the binding of both TFL and FL to ctDNA was groove mode. The FT-IR analyses suggested the A-T region of the minor groove of ctDNA as the preferential binding for TFL and FL, which was confirmed by the displacement assays with Hoechst 33258 probe, and the molecular docking visualized the specific binding. The changes in CD spectra indicated that both FL and TFL induced the perturbation on the base stacking and helicity of B-DNA, but the disturbance caused by FL was more obvious. Gel electrophoresis analyses indicated that both TFL and FL did not cause significant DNA cleavage. This study provides novel insights into the binding properties of TFL/FL with ctDNA and its toxic mechanisms.


Assuntos
DNA/metabolismo , Nitrilas/metabolismo , Praguicidas/metabolismo , Piretrinas/metabolismo , Animais , Sítios de Ligação , Bovinos , DNA/química , Clivagem do DNA/efeitos dos fármacos , Modelos Moleculares , Nitrilas/química , Conformação de Ácido Nucleico , Desnaturação de Ácido Nucleico/efeitos dos fármacos , Praguicidas/química , Piretrinas/química , Termodinâmica
3.
J Photochem Photobiol B ; 138: 109-17, 2014 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-24927231

RESUMO

The binding properties of chlorpropham (CIPC) to calf thymus DNA (ctDNA) were investigated in vitro by UV-vis absorption, fluorescence, circular dichroism (CD) and Fourier transform infrared (FT-IR) spectroscopy coupled with molecular modeling method. The results obtained from UV-vis absorption, fluorescence and CD spectroscopic methods as well as DNA viscosity and melting measurements indicated that the binding of CIPC to ctDNA was an intercalative mode. The FT-IR analysis and molecular modeling showed that CIPC mainly bound to guanine base of ctDNA. The association constant of the ctDNA-CIPC complex was determined to be in the order of 10(4) L mol(-1) by fluorescence titration. The calculated enthalpy change and entropy change suggested that hydrophobic forces and hydrogen bonds played prominent roles in the binding process. Furthermore, multivariate curve resolution-alternating least squares (MCR-ALS) approach was used to analyze the combined UV-vis absorption data matrix from the CIPC-ctDNA reaction system. The concentration profiles of the reaction components (CIPC, ctDNA and CIPC-ctDNA complex) and their pure spectra were successfully obtained to monitor the process of CIPC interaction with ctDNA. This study may contribute to the understanding of the CIPC-ctDNA interaction mechanism and toxicological effect of CIPC at the molecular level.


Assuntos
Clorprofam/química , DNA/química , Herbicidas/química , Modelos Moleculares , Animais , Bovinos , Dicroísmo Circular , Entropia , Transição de Fase , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Viscosidade
4.
Microbiology ; (12)2008.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-685984

RESUMO

In order to increase the production of insecticidal crystal proteins Cry1 and Cry2, firstly, Plack-ett-Burman design was applied to evaluate the effectiveness of the related nutrition factors; it was found that the soybean powder and MnSO4?H2O were significant factors for Cry1 production, but the yield of Cry2 wasn’t effected remarkably in such medium. Then the steepest ascent experiment was adopted to approach the optimal region of the medium composition. Lastly, the optimal concentration of the soybean powder and MnSO4?H2O was 11.5 and 0.02 g/L, obtained by response surface methodology (RSM). The final yields of Cry1 and Cry2 was 0.32 mg/mL and 0.11 mg/mL, increasing twice more than that in the medium optimized before. The median lethal concentration (LC50) of optimal medium was 1.09 ?L/mL. The toxicity to Heli-coverpa armigera was significantly enhanced than the old one.

5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-586937

RESUMO

This paper discusses the present situation of the air-station medical equipment digital construction,and analyzes the common problems at present.According to the integration spirit of superior department,this paper designs air-station medical database and presents the solutions to realize resource integration and information sharing.

6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-592107

RESUMO

Objective To promote health service information system for air force air-station. Methods According to service characters and demands of air force air-station, a general database was designed to integrate health information of pilots, health service of air-station, and physiology & psychology detection of pilots. Results It provided automatic and intelligent means for health service information and health information of pilots for all level health division of air force. Conclusion The successful running of the system enhances the service support efficiency of air force air-station, thus positively promoting the battle effectiveness.

7.
Microbiology ; (12)1992.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-684000

RESUMO

Along with the development of computer techniques and the dissemination of Internet,many investigators of microorganisms already can acquire a lot of knowledge of many fields on microbe via Internet,extremely including the whole genome of a certain microbe. This was considered unimaginable in the past.Rapid collection of information also to a great extent expands the researching ranges and researching ability of microbial researcher,and at one time,the highly developed Internet provides a unprecedented opportunity for intercommunication of information?share of resources and international cooperations of microbiology.

8.
Microbiology ; (12)1992.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-684313

RESUMO

Two high protease producing strains, whic h are desi gnated Aspergillus oryzae AS100 and AS102, were screened and applied as main fermentation strains of swine blood meal. A Saccharomyces cerevisiae Y113 and a Bacillus Asp007 were also used as assistant fermentation strains. The enzyme production abilities we re studied,and a series of parameters of the fermentation technology were deter mined. Through swine blood meal fermentation, a high-protein fermented feed wa s produced, which is strong soy flavor and was rich in protein(69%), free amino acid, vitamin such as VitD 3 and niacin and organic elements such as Fe. It is a kind of high-protein feed for animals and it could be used as feedstuff addi tive.

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