37 research outputs found
Robotic Ankle Training Improves Sensorimotor Functions in Children with Cerebral Palsy—A Pilot Study
Children with cerebral palsy (CP) have sensorimotor impairments including weakness, spasticity, reduced motor control and sensory deficits. Proprioceptive dysfunction compounds the decreased motor control and mobility. The aims of this paper were to (1) examine proprioceptive deficit of lower extremities of children with CP; (2) study improvement in proprioception and clinical impairments through robotic ankle training (RAT). Eight children with CP participated in a 6-week RAT with pre and post ankle proprioception, clinical, biomechanical assessment compared to the assessment of eight typically developing children (TDC). The children with CP participated in passive stretching (20 min/session) and active movement training (20 to 30 min/session) using an ankle rehabilitation robot (3 sessions/week over 6 weeks, total of 18 sessions). Proprioceptive acuity measured as the plantar and dorsi-flexion motion at which the children recognized the movement was 3.60 ± 2.28° in dorsiflexion and −3.72 ± 2.38° in plantar flexion for the CP group, inferior to that of the TDC group’s 0.94 ± 0.43° in dorsiflexion (p = 0.027) and −0.86 ± 0.48° in plantar flexion (p = 0.012). After training, ankle motor and sensory functions were improved in children with CP, with the dorsiflexion strength increased from 3.61 ± 3.75 Nm to 7.48 ± 2.75 Nm (p = 0.018) and plantar flexion strength increased from −11.89 ± 7.04 Nm to −17.61 ± 6.81 Nm after training (p = 0.043). The dorsiflexion AROM increased from 5.58 ± 13.18° to 15.97 ± 11.21° (p = 0.028). The proprioceptive acuity showed a trend of decline to 3.08 ± 2.07° in dorsiflexion and to −2.59 ± 1.94° in plantar flexion (p > 0.05). The RAT is a promising intervention for children with CP to improve sensorimotor functions of the lower extremities. It provided an interactive and motivating training to engage children with CP in rehabilitation to improve clinical and sensorimotor performance
The influence of a single water molecule on the reaction of BrO + HO2
Abstract The influence of a single water molecule on the BrO + HO2 hydrogen extraction reaction has been explored by taking advantage of CCSD(T)/aug-cc-pVTZ//B3LYP/6-311 + + G(d,p) method. The reaction in the absence of water have two distinct kinds of H-extraction channels to generate HOBr + O2 (1Δg) and HBr + O3, and the channel of generation of HOBr + O2 (1Δg) dominated the BrO + HO2 reaction. The rate coefficient of the most feasible channel for the BrO + HO2 reaction in the absence of water is estimated to be 1.44 × 10–11 cm3 molecule−1 s−1 at 298.15 K, which is consistent with the experiment. The introduction of water made the reaction more complex, but the products are unchanged. Four distinct channels, beginning with HO2 …H2O with BrO, H2O…HO2 with BrO, BrO…H2O with HO2, H2O…BrO with HO2 are researched. The most feasible channels, stemming from H2O…HO2 with BrO, and BrO…H2O with HO2, are much slower than the reaction of BrO + HO2 without water, respectively. Thus, the existence of water molecule takes a negative catalytic role for BrO + HO2 reaction
Changes of Shoulder, Elbow, and Wrist Stiffness Matrix Post Stroke
Stroke affects multiple joints in the arm with stereotypical patterns of arm deformity involving the shoulder, elbow, wrist, and hand and with disrupted coordination of multiple joints in active movements. However, there is a lack of systematicmethods to evaluatemulti-joints and multi-degree of freedoms (DOF) neuro-mechanical changes, especially for complex systemswith three ormore joints/ DOFs involved. This paper used a novel systematic method to characterize dynamics and control of the shoulder, elbow, and wrist of the human arm individually and simultaneously, including the couplings across themultiple joints during controlled movements. A novel method was developed to decompose the complex system into manageable single-joint level for more reliable characterizations. The method was used in clinical studies to characterize the multi-joint changes associated with spastic impaired arm of 11 patients post stroke and 12 healthy controls. It was found that stroke survivors showed not only increased stiffness at the individual joints locally but also significantly higher couplings across the joints. The relative increases in couplings are often higher than that of the local joint stiffness. The multi-joint characterization provided a tool to characterize impairment of individual patients, which would allow more focused impairment-specific treatment. In general, the decomposition method can be used for even more complex systems, making characterization of intractable system dynamics of three or more joints/DOFs manageable
Theoretical Study on the Gas Phase Reaction of Allyl Alcohol with Hydroxyl Radical
The
complex potential energy surface of allyl alcohol (CH<sub>2</sub>CHCH<sub>2</sub>OH) with hydroxyl radical (OH) has been investigated
at the G3(MP2)//MP2/6-311++G(d,p) level. On the surface, two kinds
of pathways are revealed, namely, direct hydrogen abstraction and
addition/elimination. Rice-Ramsperger-Kassel-Marcus theory and transition
state theory are carried out to calculate the total and individual
rate constants over a wide temperature and pressure region with tunneling
correction. It is predicted that CH<sub>2</sub>CHOHCH<sub>2</sub>OH
(IM1) formed by collisional stabilization is dominate in the temperature
range (200–440 K) at atmospheric pressure with N<sub>2</sub> (200–315 K at 10 Torr Ar and 100 Torr He). The production
of CH<sub>2</sub>CHCHOH + H<sub>2</sub>O via direct hydrogen abstraction
becomes dominate at higher temperature. The kinetic isotope effect
(KIE) has also been calculated for the title reaction. Moreover, the
calculated rate constants and KIE are in good agreement with the experimental
data
Measurement of the low energy
The cosmic 1.809 MeV γ-ray emitted by the radioactive nucleus 26Al in the Galaxy is one of the key observation targets of the γ-ray astronomy. The 26Al is mainly produced by the 25Mg(p,γ)26Al reaction in the stellar Mg-Al reaction cycle. At the astrophysical relevant temperatures, the reaction rates of 25Mg(p,γ)26Al are dominated by several narrow resonances at low energy. This work reports a measurement of the low energy 25Mg(p,γ)26Al resonances at Jinping Underground Nuclear Astrophysics experimental facility (JUNA) in the China Jinping Underground Laboratory (CJPL)
Mechanistic and Kinetic Study of CF<sub>3</sub>CHCH<sub>2</sub> + OH Reaction
The potential energy surfaces of the CF<sub>3</sub>CHCH<sub>2</sub> + OH reaction have been investigated at the BMC-CCSD level
based on the geometric parameters optimized at the MP2/6-311++G(d,p)
level. Various possible H (or F)-abstraction and addition/elimination
pathways are considered. Temperature- and pressure-dependent rate
constants have been determined using Rice–Ramsperger–Kassel–Marcus
theory with tunneling correction. It is shown that IM1 (CF<sub>3</sub>CHCH<sub>2</sub>OH) and IM2 (CF<sub>3</sub>CHOHCH<sub>2</sub>) formed
by collisional stabilization are major products at 100 Torr pressure
of Ar and in the temperature range of <i>T</i> < 700
K (at <i>P</i> = 700 Torr with N<sub>2</sub> as bath gas, <i>T</i> ≤ 900 K), whereas CH<sub>2</sub>CHOH and
CF<sub>3</sub> produced by the addition/elimination pathway are the
dominant end products at 700–2000 K. The production of CF<sub>3</sub>CHCH and CF<sub>3</sub>CCH<sub>2</sub> produced by hydrogen
abstractions become important at <i>T</i> ≥ 2000
K. The calculated results are in good agreement with available experimental
data. The present theoretical study is helpful for the understanding
the characteristics of the reaction of CF<sub>3</sub>CHCH<sub>2</sub> + OH