Importance of Sample Size for the Estimation of Repeater F Waves in Amyotrophic Lateral Sclerosis

Background：In amyotrophic lateral sclerosis （ALS）,repeater F waves are increased.Accurate assessment of repeater F waves requires an adequate sample size.Methods：We studied the F waves of left ulnar nerves in ALS patients.Based on the presence or absence of pyramidal signs in the left upper limb,the ALS patients were divided into two groups：One group with pyramidal signs designated as P group and the other without pyramidal signs designated as NP group.The Index repeating neurons （RN） and Index repeater F waves （Freps） were compared among the P,NP and control groups following 20 and 100 stimuli respectively.For each group,the Index RN and Index Freps obtained from 20 and 100 stimuli were compared.Results：In the P group,the Index RN （P =0.004） and Index Freps （P =0.001） obtained from 100 stimuli were significantly higher than from 20 stimuli.For F waves obtained from 20 stimuli,no significant differences were identified between the P and NP groups for Index RN （P =0.052） and Index Freps （P =0.079）; The Index RN （P ＜ 0.001） and Index Freps （P ＜ 0.001） of the P group were significantly higher than the control group; The Index RN （P =0.002） of the NP group was significantly higher than the control group.For F waves obtained from 100 stimuli,the Index RN （P ＜ 0.001） and Index Freps （P ＜ 0.001） of the P group were significantly higher than the NP group; The Index RN （P ＜ 0.001） and Index Freps （P ＜ 0.001） of the P and NP groups were significantly higher than the control group.Conclusions：Increased repeater F waves reflect increased excitability of motor neuron pool and indicate upper motor neuron dysfunction in ALS.For an accurate evaluation of repeater F waves in ALS patients especially those with moderate to severe muscle atrophy,100 stimuli would be required.

MOTOR EVOKED POTENTIAL OF MAGNETIC STIMULATION IN THE DETERMINATION OF S_1 RADICULOPATHY

Motor evoked potentlal (MEP) elicited by magnetic stimulation was utilised to diagnose S1 radiculopathy non-invasively. Magnetic stimulation estimated motor nerve conduction time (MNCT), which was used in combination with F response recorded from soleus, allowed calculation of motor root conduction time (MRCT). 50 healthy controls and 30 patients with S1 radiculopathy were studied- The results showed that no difference was seen in MNCT in all patients, but MRCT were markedly prolonged in 87% of the patients, which was higher than the prolongation of F wave latency in 71% or the patients. it is concluded that MEP of magnetic stimulation is a useful technique for non-invasive diagnosis of S, radiculopathy.

Characteristics of Soliton with Dynamic Constraints on its Existence/Propagation in Tropical Easterly Wave

The study concerns the propagation of easterly wave (EW) at tropics as west-moving soliton more steady both in ionn and velocity as evidenced in the dynamic framework.Under the impact of different circulation patterns over the regions of western Pacific trade wind,South-Asia monsoon and their transition,such a soliton becomes tapering off during its westward movement and degrading to a common dispersive wave on the whole,followed by dismtegra-non when striking the South-China Sea monsoon segment,thereby indicating that the sea sector is inaccessible to the soliton When no monsoon trough is present over the South Asian monsoon area around 30癗 or the monsoon depression ]S shallow,it is likely to have west-travelling soliton,which suggests the incursion of the EW into the South-Asian monsoon region.

Scattering of Scalar Wave by Extended Black Hole in f(R) Gravity

We analyze the Sehrodinger-type scalar wave equation of an extended black hole in f（R） gravity, and numerically investigate its absorption/scattering cross sections using the partial wave method. It is found that the dimension of length a makes the peak value of the effective scattering potential fall down, and the absorption cross section oscillates around the geometric optical value in the high frequency regime. We can also see that the scattering flux becomes stronger and its angle width becomes narrower in the forward direction, the glory peak becomes lower and the glory width becomes narrower along the backward direction when the coupling parameter α increases.

F Wave Study in Amyotrophic Lateral Sclerosis： Assessmen of Segmental Motoneuronal Dysfunction

Background： Dysfunctional spinal circuit may play a role in the pathophysiology ofarnyotrophic lateral sclerosis （ALS）. The purpose of this study was to use F waves for assessment of segmental motoneuronal excitability following upper motor neuron （UMN） dysfunctions in ALS. Meihods： We studied the F waves of 152 ulnar nerves recorded fi＇om abductor digiti minimi in 82 patients with ALS. Two groups of hands were defined based on the presence or absence of pyramidal signs in the same upper limb. The group with pyramidal signs in tile upper limbs was designated as the P group, and the group without pyramidal signs in the upper limbs was designated as the NP group. Results： The mean （P 〈 0.001）, median （P 〈 0.001） and maximum （P = 0.035） F wave amplitudes, mean （P 〈 0.001 ）, median （P 〈 0.001） and maximum （P - 0.003） F/M amplitude ratio, index repeating neuron （P 〈 0.001 ） and index repeater F waves （P 〈 0.001 ） of the P group were significantly increased compared with the NP group. No significant differences were identified for F wave chronodispersion （P= 0.628）, mean F wave latency （P 0.151 ）, minimum F wave latency （P = 0.211 ）, maximum F wave latency （13 = 0. 199）. F wave persistence （P = 0.738）. F wave duration （P = 0. 152）, F wave conduction velocity （P = 0.813） and number of giant F waves （P = 0.072） between the two groups. Conclusions＂ In this study, increased F wave amplitude, F/M amplitude ratio and number of repeater F waves reflected enhanced segmental lnotoneuronal excitability following UMN dysfunctions in ALS.