Reaction Time Control Research Articles

Correlations of psycho-physiological parameters influencing the physical fitness of aged women.

Regular assessment of psycho-physiological parameters in aged subjects helps to clarify physical and mental conditions which are important in the prevention of health-endangering events to assure a healthy aging. Thirty older care female residents consented voluntarily to participate in the study. The somatic and psycho-physiological parameters recorded were handgrip force, disjunctive reaction time, balance control and whole body movement coordination, the electrocardiogram and heart rate variability. Significant correlations were found between (a) reaction time and balance control efficiency (r = -0.567, p < 0.009), (b) reaction time and movement coordination accuracy (r = -0.453, p < 0.045), (c) cardiac state and movement coordination accuracy (r = 0.545, p < 0.016), (d) cardiac stress and cardiac state (r = -0.495, p < 0.031), and (e) cardiac stress and force (r = -0.822, p < 0.045). In conclusion, for the aim of establishing basic battery tests for assessing psycho-physiological condition of physical fitness our results emphasize the importance of systematic physical activity, endurance and strength training supporting muscle force, balance control and whole-body movement coordination, in addition to improving the cardiac stress index level. The strong interrelation among these parameters allows the drawing of a more complete view regarding the health condition of aged individuals.

Longer reaction time of the fibularis longus muscle and reduced postural control in basketball players with functional ankle instability: A pilot study

BackgroundMotor control evaluation in subjects with functional ankle instability is questionable when both ankles of the same subject are compared (affected vs non-affected). ObjectiveTo compare the postural control and reaction time of ankle muscles among: basketball players with FAI (instability group), basketball players without FAI (non-instability group) and healthy non-basketball-playing participants (control group). DesignCase-control study. SettingLaboratory. ParticipantsInstability (n = 10), non-instability (n = 10), and control groups (n = 11). Main outcome measuresCentre of pressure variables (area, velocity and sway) were measured with a force platform. Reaction time of ankle muscles was measured via electromyography. ResultsA one-way ANOVA demonstrated that there were significant differences between the instability and non-instability groups in the fibularis longus (p < 0.001), fibularis brevis (p = 0.031) and tibialis anterior (p = 0.049) muscles. Repeated-measures ANOVA and post hoc analysis determined significant differences for the area between the instability and non-instability groups (p = 0.001). ConclusionBasketball players with FAI have reduced postural control and longer reaction time of the fibularis and tibialis anterior muscles.

Motor imagery for severely motor-impaired patients: evidence for brain-computer interfacing as superior control solution.

Brain-Computer Interfaces (BCIs) strive to decode brain signals into control commands for severely handicapped people with no means of muscular control. These potential users of noninvasive BCIs display a large range of physical and mental conditions. Prior studies have shown the general applicability of BCI with patients, with the conflict of either using many training sessions or studying only moderately restricted patients. We present a BCI system designed to establish external control for severely motor-impaired patients within a very short time. Within only six experimental sessions, three out of four patients were able to gain significant control over the BCI, which was based on motor imagery or attempted execution. For the most affected patient, we found evidence that the BCI could outperform the best assistive technology (AT) of the patient in terms of control accuracy, reaction time and information transfer rate. We credit this success to the applied user-centered design approach and to a highly flexible technical setup. State-of-the art machine learning methods allowed the exploitation and combination of multiple relevant features contained in the EEG, which rapidly enabled the patients to gain substantial BCI control. Thus, we could show the feasibility of a flexible and tailorable BCI application in severely disabled users. This can be considered a significant success for two reasons: Firstly, the results were obtained within a short period of time, matching the tight clinical requirements. Secondly, the participating patients showed, compared to most other studies, very severe communication deficits. They were dependent on everyday use of AT and two patients were in a locked-in state. For the most affected patient a reliable communication was rarely possible with existing AT.

Research on the Controllable Preparation of Silver Nanowires in Conductive Adhesives

One dimensional nanomaterials are used as the basic and significant parts to fabricate nanodevices. Silver nanowire is a promising conductive particle, which can be used in conductive adhensives. The research is about the effects of the control agents, reaction temperature, and reaction time on the morphology and size of the product. And figure out an effective way to control the nucleation and the morphology of silver nanowires.

The Development and Application on Composite Resin Substituted for Cement Slurry

A type of composite resin substituted for cement slurry was developed for channelling and leakoff blockage in oil production and water injection wells of sandstone reservoirs in Huabei oilfields.Laboratory evaluation showed that the controlled reaction time was 3~8h at 40~110°C,the tensile strength of curing samples was 10.8 ~ 13.1 MPa, the compressive strength 13 ~ 87MPa, and the shear strength 9.2 ~ 28.9MPa.Any corrosion ratio in 10%HClNaOHNaCl was less than 1% at 100°C for 24 hours. Field application was successful and the pressure drop was less than 0.5MPa after shuting down for 30min.

Microstructure and Spectral Characteristics of Graphene Oxide during Reduction

In the paper, graphite oxide was prepared with the improved Hummers Method and then dispersed in water via ultrasonic dispersion to produce dispersion liquid. After the reduction with hydrazine hydrate, graphene colloidal dispersion liquid with different reduced degrees was obtained via controlling reaction time. Microstructure and crystal structure evolution were characterized via UV-visible absorption spectroscopy, infrared spectroscopy and scanning probe microscopy from the samples during the transition from graphene oxide to graphene. Here, we analyzed the time-variation relationship of graphene oxide surface functional groups, conjugated π bond, the single-layer thickness and particle size during the reduction. The obtained results showed that microstructure and surface structure had certain correlation and regularity that functional groups on graphene oxide surface, conjugated π bond, the single-layer thickness and sheet diameter had the identical evolution process.

Facile synthesis of rice shaped CuO nanostructures for battery application

The oxides of transition metals are an important class of semiconductors, which have applications in electronics, magnetic storage media, solar applications and catalysis. Among them, CuO has attracted much attention due to its widespread applications. In this paper, a facile synthesis of rice shaped CuO nanostructures have been prepared by reflux method for battery application using Copper nitrate and ammonia as precursors. Samples were prepared at three different reaction timings namely 6, 12 and 24 h. The as-prepared samples were calcinated at 400 °C to ensure the formation of copper oxide. The final products were subjected to X-ray diffraction, scanning electron microscopy, FT-IR and UV–Vis spectroscopy in order to study the effect of reaction time on the properties of the prepared copper oxide nanostructures. It is found that at controlled reaction time rice shaped CuO nanostructures are obtained. Cyclic voltammogram was recorded to understand the electrocatalytic behaviors of the rice shaped CuO sample prepared under optimized condition.

Characterization of a DAPI-RIT-DAPI System for Gas-Phase Ion/Molecule and Ion/Ion Reactions

The discontinuous atmospheric pressure interface (DAPI) has been developed as a facile means for efficiently introducing ions generated at atmospheric pressure to an ion trap in vacuum [e.g., a rectilinear ion trap (RIT)] for mass analysis. Introduction of multiple beams of ions or neutral species through two DAPIs into a single RIT has been previously demonstrated. In this study, a home-built instrument with a DAPI-RIT-DAPI configuration has been characterized for the study of gas-phase ion/molecule and ion/ion reactions. The reaction species, including ions or neutrals, can be introduced from both ends of the RIT through the two DAPIs without complicated ion optics or differential pumping stages. The primary reactant ions were isolated prior to reaction and the product ions were mass analyzed after controlled reaction time period. Ion/molecule reactions involving peptide radical ions and proton-transfer ion/ion reactions have been carried out using this instrument. The gas dynamic effect due to the DAPI operation on internal energy deposition and the reactivity of peptide radical ions has been characterized. The DAPI-RIT-DAPI system also has a unique feature for allowing the ion reactions to be carried out at significantly elevated pressures (in 10(-1) Torr range), which has been found to be helpful to speed up the reactions. The viability and flexibility of the DAPI-RIT-DAPI system for the study of gas-phase ion reactions have been demonstrated.

SAT0231 Diffusion tensor imaging and cogntive performance in NPSLE

BackgroundOne of the most common manifestations of Neuropsychiatric SLE (NPSLE) is cognitive dysfunction, which is present in up to 80% of patients [1]. NPSLE presents a diagnostic challenge as it...

Chemical Modification of Natural Rubber in the Latex Stage by Grafting Cardanol, a Waste from the Cashew Industry and a Renewable Resource

Cardanol, an agricultural byproduct of the cashew industry, is a cheap and abundantly available renewable resource. The multifunctional activity of cardanol in the rubber and polymer industries has been well-established in recent years. The present study highlights the chemical grafting of cardanol onto natural rubber in the latex stage. The cardanol grafted natural rubber is characterized by FTIR and NMR spectroscopies. The grafting parameters have been optimized for maximum yield in terms of percent grafting and grafting efficiency by the Taguchi method. Four control factors, i.e., initiator concentration, cardanol concentration, reaction temperature, and reaction time, are chosen at three different levels. The optimum parameter combination is found to be the initiator concentration 2 phr, cardanol concentration 10 phr, reaction temperature 65 °C, and reaction time 6 h. The analysis of variance method is used to evaluate the percentage contributions of the different control factors on the percent grafti...

Quantitative analysis of 5-HMF produced from fructose

Quantitative analysis of 5-hydroxymethylfufural (5-HMF) conversion from fructose by dehydration and rearrangement was investigated by <TEX>$^1H$</TEX>-NMR spectroscopic method. Fructose was converted to 5-HMF in dimethylsulfoxide (DMSO)-<TEX>$d^6$</TEX> or acidic deuterium hydroxide at controlled reaction temperature and time. With addition of internal standards (biphenyl for DMSO-<TEX>$d^6$</TEX> solvent, and 2,5-dihydroxybenzoic acid for deuterium oxide solvent), conversion from fructose to 5-HMF was analyzed by <TEX>$^1H$</TEX>-NMR spectroscopy. Quantitative analysis was run by comparison with peak area integration between of 5-HMF and internal standard. In DMSO solvent, 5-HMF was stable end product but part of 5-HMF was converted to formic and levulinic acid at acidic aqueous medium.

Preparation of Rod-like ZnO Micro/Nano-crystals by Imidazolium Ionic Liquid Assisted Hydrothermal Method

ZnO crystals with different morphologies were prepared by hydrothermal method using zinc acetate dihydrate and sodium hydroxide as raw materials and the mixture of 1-alkyl-3-methylimidazolium chloride ionic liquid(Cl,Cl,Cl or Cl) and water as the solvent.The as-prepared samples were characterized by scanning electron microscopy(SEM) and X-ray diffraction(XRD).The effects of alkyl chain lengths of imidazolium ionic liquids,the dosage of ionic liquids,reaction time and temperature on ZnO crystals during the formation process were investigated.The results indicate that the structures of the ZnO rods are hexagonal wurtzite.It is very important to select different ionic liquids and their dosage and to control reaction time and temperature in preparation of ZnO crystals with different morphologies.

Selective conversion of glucose into lactic acid and acetic acid with copper oxide under hydrothermal conditions

Biomass as a source for chemicals production attracts growing attention due to the decreasing storage of fossil fuels and global warming caused by emission of CO2. In this study, conversion of glucose with copper oxide (CuO) was studied under alkaline hydrothermal conditions using a batch reactor and continuous flow reactor. CuO, as an oxidant, greatly improves the yields of lactic acid (LA) and acetic acid from glucose and was reduced into Cu2O and Cu. Selective production of LA with the highest yield of 59% and acetic acid with the highest yield of 32% can be achieved by controlling reaction time, temperature, and addition of CuO. A possible mechanism of conversion of glucose with CuO was proposed. © 2012 American Institute of Chemical Engineers AIChE J, 59: 2096–2104, 2013

Carbon sphere as a black pigment for an electronic paper

Carbon black, a black material popular for use in electronic paper, could limit the performance of the electronic paper due to its non-uniform structure. Carbon spheres, with spherical shape and relatively narrow size distribution, are expected to overcome this limitation and substitute for carbon black in the electronic paper. Carbon spheres were synthesized through a hydrothermal reaction using glucose as a raw material. By controlling reaction time and glucose concentration, appropriate non-agglomerated carbon spheres with an average diameter of 202.26 (±26.15) nm were fabricated. To increase their dispersibility in dielectric fluid, p-(2-ethylhexyl acrylate) was grafted onto the surface of the carbon spheres. Then, acid and base charge control agents were mixed with the carbon spheres to produce a pigment with higher mobility in the dielectric fluid. The optimized combination of pigment, charge control agent and solvent reveals reasonably fast switching time of about 540 ms.

Highlights of Photochemical Reactions in Microflow Reactors

AbstractThis review highlights selected examples of photochemical transformations in microflow reactors. The main advantages of microflow reactors over conventional batch systems are superior light penetrations, controlled reaction times, precise temperature control and removal of photoproducts from the irradiated area. These features typically result in higher conversions or yields, improved selectivity, enhanced energy efficiencies and reductions of solvent volumes and consequently waste. Different types of homogeneous and heterogeneous reactions are presented, showing the superiority of microflow photochemistry over batch processes.

Electrochemical coupling of mono and dihalopyridines catalyzed by nickel complex in undivided cell

One step nickel-catalyzed electroreductive homocoupling among 2-bromopicolines and 2-bromopyridine has been investigated by our group in an undivided cell and using zinc or iron as sacrificial anode. In this work, it was developed mono and dihalopyridines coupling to obtain possible products from heterocoupling. A series of reactions were carried out in order to develop a synthetic method for the preparation of unsymmetrical 2,2′-bipyridines and 2,2′:6′,2″-terpyridines. Statistical yields (50%) were observed for 2-bromopyridines/2-bromo-6-methylpyridine heterocoupling. In a preliminary study devoted to terpyridines preparation, good results were obtained for 2,6-dihalopyridines homocoupling, affording 2,6-dichloro-2,2′-bipyridine (46%) and 2,6-dibromo-2,2′-bipyridine (56%), at controlled reaction time. At major reaction time, it was observed that the direct electroreduction of the 2,6′-dihalo-2,2′-bipyridines intermediates and 2,6″-dihalo-2,2′:6′,2″-terpyridines products on the cathode surface. A reasonable isolated product yield of 6,6″-dimethyl-2,2′:6′,2″-terpyridine (10%) was only observed in the reaction between 2,6-dichloropyridine and 2-bromo-6-methylpyridine (1:2).

Low dosage promethazine and loratadine negatively affect neuromotor function

ObjectivesDetermine how the sedating antihistamine promethazine and non-sedating antihistamine loratadine at a dose of 10mg influence voluntary and involuntary motor processes in the hours following ingestion and the morning after ingestion. MethodsEight healthy young adults were recruited into a human double-blind, placebo-controlled, three-way crossover study. Neuromotor function was examined using a battery of controlled reaction time, postural tremor, and heart rate variability measures. Neuromotor function was assessed 4 times for each of the promethazine, loratadine and placebo interventions; pre-ingestion, 1h post-ingestion, 2h post-ingestion, and the following day. ResultsSelf-perceived levels of drowsiness increased only after ingestion of promethazine. However, both antihistamines had negative effects on simple reaction time, choice reaction time, the RMS and peak power amplitude of postural tremor, and autonomic cardiac regulation. ConclusionsThe presence of selective neuromotor deficits following ingestion of promethazine and loratadine suggest that sedating and non-sedating antihistamines alter neuromotor function. It is possible that the H1 antagonists used in this study have antimuscarinic effects, which may impact on the central dopaminergic system that plays a role in modulating several CNS processes associated with movement. SignificanceAntihistamines are one of the most commonly procured over-the-counter medications. The current study suggests that taking non-sedating antihistamines to avoid the adverse drug reaction of drowsiness may not avoid unwanted motor control side-effects.

Synthesis of CdTe and CdTe/CdS Core-Shell Quantum Dots and their Optical Properties

This paper describes the synthesis of CdTe and CdTe/CdS core-shell quantum dots (QDs) in aqueous solution. The quantum dots are prepared by using thioglycolic acid (TGA) as stabilizers. The synthesis procedure is simple and controllable. Different sized CdTe QDs with tuned PL wavelengths from 550 to 640 nm was synthesized by controlling reaction time within 5 h in aqueous solutions at a temperature of 100 °C. We also investigated the influence of precursor Cd/Te molar ratio for the prepared QDs. It was showed that the core-shell CdTe/CdS QDs have larger photoluminescence (PL) emission intensity than the original CdTe QDs. The synthesized core-shell CdTe/ZnS QDs have high quality, water-soluble and will be useful in applications of biolabeling, biosensing, and imaging.

타블렛 형태 급결제가 콘크리트의 응결시간 및 조기강도에 미치는 영향에 관한 연구

한중 콘크리트 타설시 발생되는 초기 동해로 인한 피해를 방지하고 조강성을 향상시키기 위해 열풍기 사용을 통한 보양, 결합수와 골재의 가열 및 시멘트 사용량을 늘리는 방법, 급결제 및 촉진제를 사용하는 등 다양한 방법이 사용되고 있다. 하지만 이러한 방법은 사용상의 어려움과 에너지 소비 및 생산비의 증가에 따른 경제성 감소 등의 문제점을 가지고 있다. 이중 급결제 및 촉진제의 사용은 경제적 이지만 수화 초기부터 급격하게 반응하여 급결하는 특성 때문에 작업성의 확보가 어렵다는 문제점을 가지고 있다. 이에 이 논문에서는 기존 의약 분야에서 주로 이용되는 약물의 고형 투여 형태인 정제(Tablet)화 방법을 이용하여 급결제와의 응결 시간을 비교하였고, 이 결과를 토대로 콘크리트의 물리적 특성 및 역학적 특성 시험을 실시하여 일정 시간 동안 작업이 가능하고 초기동해 방지 및 조강성이 향상 되는지 확인 하였다. 그 결과 급결제 및 타블렛의 경우 사용량이 증가 할수록 응결 시간이 줄어드는 것을 확인하였고, 콘크리트의 물리적·역학적 시험에서는 경시 변화에 대하여 Control과 비교 타블렛0.5%, 1.0%가 일정 시간 동안 작업 시간 확보가 가능함을 확인하였을 뿐만 아니라 조기 강도에서도 급결제 0.5%와 타블렛 0.5%, 1.0%가 뛰어난 조기 강도 발현 특성을 보여주었다.

Synthesis of controlled thermoresponsive PET track‐etched membranes by ATRP method

AbstractControlled thermoresponsive PET track‐etched membranes were synthesized by grafting N‐isopropylacrylamide (NIPAAm) onto the membrane surface via atom transfer radical polymerization (ATRP). The initial measurements were made to determine the anchoring of ATRP initiator on PET membrane surface. Thereafter, polymerization was carried out to control the mass of polymer by controlling reaction time grafted from the membrane surface and, ATR‐FTIR, grafting degree measurements, water contact angle measurements, TGA, and SEM were used to characterize changes in the chemical functionality, surface and pore morphology of membranes as a result of modification. Water flux measurements were used to evaluate the thermoresponsive capacity of grafted membranes. The results show the grafted PET track‐etched membranes exhibit rapid and reversible response of permeability to environmental temperature, and its permeability could be controlled by controlling polymerization time using ATRP method. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.