Osteoarthritis of knee is a common problem in the elderly population worldwide. Physical therapy has been shown to be useful in decreasing pain and increasing mobility in this population. The aim of this study was to ...Osteoarthritis of knee is a common problem in the elderly population worldwide. Physical therapy has been shown to be useful in decreasing pain and increasing mobility in this population. The aim of this study was to study the effectiveness of slow reversal hold and isometric exercise techniques in reducing pain, increasing muscle strength, and increasing range of motion for knee flexion in patients with osteoarthritis of knee. The other aim of this study was to compare the relative effectiveness of these two interventions. 60 subjects participated in this study and were randomly assigned either to the slow reversal hold group (n = 30) or, to the isometrics exercise group (n = 30). All subjects performed their respective exercises for 3 weeks. Pain scores using the visual analog scale, muscle strength using manual muscle testing of quadriceps and hamstrings, and range of motion (ROM) for knee flexion using a goniometer were recorded both pre-treatment and post-treatment for both left and right knees. Both the interventions showed a significant decrease in pain scores, an increase in muscle strength, as well as an increase in the ROM. However, ROM was significantly increased in the slow reversal hold group as compared to the isometrics group in both knees. It was concluded that both exercise techniques could be useful in patients with osteoarthritis of knee for decreasing pain and increasing muscle strength. Slow reversal hold technique might be a better technique than isometrics for increasing ROM for knee flexion.展开更多
Increased neck strength has been linked to a potential decrease in traumatic brain injuries(TBI).The purpose was to determine the efficacy of a neck-strengthening protocol using a novel neck-strengthening device to in...Increased neck strength has been linked to a potential decrease in traumatic brain injuries(TBI).The purpose was to determine the efficacy of a neck-strengthening protocol using a novel neck-strengthening device to increase isometric neck strength and rate of force development(RFD).Utilizing self-generated centripetal force,participants trained for 14 weeks.A linear mixed model was used to analyze the relationship between post-assessment measurements and pre-assessments measurements,while accounting for repeated measure random effect at the individual level,and a regular random error term.RFD values were 4.344 times higher in the clockwise direction and 5.978 times higher in the counterclockwise direction when comparing pre and post assessment measurements.Isometric neck strength increased significantly(p<0.05)in the cervical extension(p=0.010)and left lateral flexion(p=0.009)directions.The results can be used in strength training and clinical settings to potentially reduce the incidence of TBI.展开更多
Low back pain(LPB)is a common and impactful health concern globally,affecting individuals across various demographics and imposing a significant burden on the health care system.Nonspecific chronic LBP(NCLBP),charac-t...Low back pain(LPB)is a common and impactful health concern globally,affecting individuals across various demographics and imposing a significant burden on the health care system.Nonspecific chronic LBP(NCLBP),charac-terized as pain lasting over 12 weeks without an identifiable cause,leads to notable functional limitations and reduced quality of life.Traditional rehabil-itation programs,often focusing on dynamic exercises for lumbar strengthening,typically do not target the deep stabilizing muscles crucial for lumbar support and effective recovery.Multi-angular isometric lumbar exercise(MAILE)offers a low-impact method for strengthening lumbar stabilizers through multi-angular isometric contractions,reducing risks from dynamic movements.This article examines MAILE’s potential in addressing motor control dysfunctions in NCLBP,highlighting studies on lumbar muscle activation,core stability,and isometric exercises.The article explores the prevalence and socioeconomic impact of NCLBP in the Middle East,highlighting the need for affordable treatment options in areas like Qatar and Saudi Arabia.This article aims to validate the efficacy of MAILE in reducing pain,enhancing mobility,and improving lumbar stability,offering a valuable option for NCLBP management.Future research should focus on large-scale clinical trials to substantiate these findings and guide clinical practice.展开更多
Precise traffic flow forecasting is essential for mitigating urban traffic congestion.However,it is difficult for existing methods to adequately capture the dynamic spatio-temporal characteristics and multiscale tempo...Precise traffic flow forecasting is essential for mitigating urban traffic congestion.However,it is difficult for existing methods to adequately capture the dynamic spatio-temporal characteristics and multiscale temporal dependencies of traffic flow.A traffic flow prediction model with multiscale temporal awareness and graph diffusion attention networks(MT-GDAN)is proposed to address these issues.Specifically,a graph diffusion attention module is constructed,which dynamically adjusts and calculates the weights of neighboring nodes in the graph structure using a random graph attention network(GAT)and captures the spatial characteristics of hidden nodes through an adaptive adjacency matrix,thus better exploiting the dynamic spatio-temporal properties of traffic flow.Secondly,a multiscale isometric convolutional network and bi-level routing attention are used to construct a multiscale temporal awareness module.The former extracts local information of traffic flow segments by convolution with different sizes of convolution kernels and then introduces isometric convolution to obtain the global temporal relationship between local features of traffic flow segments;the latter filters irrelevant spatio-temporal features at a coarse regional level and focuses locally on key points to more accurately capture the multiscale temporal dependencies of traffic flows.Experimental results reveal that the MT-GDAN model surpasses the mainstream baseline model in terms of forecasting accuracy and exhibits good prediction performance.展开更多
Abstract This paper gencralizes the result about linear isometries of S~ spaces given by W.P.Novinger and D.M.Oberlin[2]for the unite dise of C to the bounded symmetric domains of C^n
AIM： To investigate the role of opioid p-receptor subtype in opiate-induced constipation （OIC）.METHODS： The effect of Ioperamide on intestinal transit was investigated in mice. Ileum strips were isolated from 12-w...AIM： To investigate the role of opioid p-receptor subtype in opiate-induced constipation （OIC）.METHODS： The effect of Ioperamide on intestinal transit was investigated in mice. Ileum strips were isolated from 12-wk-old male BALB/c mice for identification of isometric tension. The ileum strips were precontracted with 1 μmol/L acetylcholine （ACh）. Then, decrease in muscle tone （relaxation） was characterized after cumu- lative administration of 0.1-10μ~mol/L Ioperamide into the organ bath, for a concentration-dependent study. Specific blockers or antagonists were used for pretreat- ment to compare the changes in Ioperamide-induced relaxation.RESULTS： In addition to the delay in intestinal transit, Ioperamide produced a marked relaxation in isolated ileum precontracted with ACh, in a dose-dependent manner. This relaxation was abolished by cyprodime,a selective opioid p-receptor antagonist, but not modified by naloxonazine at a dose sufficient to block opioid μ-1 receptors. Also, treatment with opioid μ-1 receptor agonist failed to modify the muscle tone. Moreover, the relaxation by Ioperamide was attenuated by glibenclamide at a dose sufficient to block ATP-sensitive K^＋ （KATP） channels, and by protein kinase A （PKA） inhibitor, but was enhanced by an inhibitor of phosphodiesterase for cyclic adenosine monophosphate （cAMP）.CONCLUSION： Loperamide induces intestinal relaxa- tion by activation of opioid μ-2 receptors via the cAMP- PKA pathway to open KATp channels, relates to OIC.展开更多
In order to detect and assess the muscle fatigue state with the surface electromyography(sEMG) characteristic parameters,this paper carried out a series of isometric contraction experiments to induce the fatigue on th...In order to detect and assess the muscle fatigue state with the surface electromyography(sEMG) characteristic parameters,this paper carried out a series of isometric contraction experiments to induce the fatigue on the forearm muscles from four subjects,and recorded the sEMG signals of the flexor carpi ulnaris.sEMG's median frequency(MDF) and mean frequency(MF) were extracted by short term Fourier transform(STFT),and the root mean square(RMS) of wavelet coefficients in the frequency band of 5—45 Hz was obtained by continuous wavelet transform(CWT).The results demonstrate that both MDF and MF show downward trends within 1 min; however,RMS shows an upward trend within the same time.The three parameters are closely correlated with absolute values of mean correlation coefficients greater than 0.8.It is suggested that the three parameters above can be used as reliable indicators to evaluate the level of muscle fatigue during isometric contractions.展开更多
Biomass allocation patterns among plant species are related to their adaptive ecological strategies. Ephemeral, ephemeroid and annual plant life forms represent three typical growth strategies of plants that grow in a...Biomass allocation patterns among plant species are related to their adaptive ecological strategies. Ephemeral, ephemeroid and annual plant life forms represent three typical growth strategies of plants that grow in autumn and early spring in the cold deserts of China. These plants play an important role in reducing wind velocity in the desert areas. However, despite numerous studies, the strategies of biomass allocation among plant species with these three life forms remain contentious. In this study, we conducted a preliminary quadrat study during 2014–2016 in the southern part of the Gurbantunggut Desert, China, to investigate the allocation patterns of above-ground biomass(AGB) and below-ground biomass(BGB) at the individual level in 17 ephemeral, 3 ephemeroid and 4 annual plant species. Since ephemeral plants can germinate in autumn, we also compared biomass allocation patterns between plants that germinated in autumn 2015 and spring 2016 for 4 common ephemeral species. The healthy mature individual plants of each species were sampled and the AGB, BGB, total biomass(TB), leaf mass ratio(LMR) and root/shoot ratio(R/S) were calculated for 201 sample quadrats in the study area. We also studied the relationships between AGB and BGB of plants with the three different life forms(ephemeral, ephemeroid and annual). The mean AGB values of ephemeral, ephemeroid and annual plants were 0.806, 3.759 and 1.546 g/plant, respectively, and the mean BGB values were 0.106, 4.996 and 0.166 g/plant, respectively. The mean R/S value was significantly higher in ephemeroid plants(1.675) than in ephemeral(0.154) and annual(0.147) plants. The mean LMR was the highest in annual plants, followed by ephemeroid plants and ephemeral plants, reflecting the fact that annual plants allocate more biomass to leaves, associated with their longer life span. Biomass of ephemeral plants that germinated in autumn was significantly higher than those of corresponding plants that germinated in spring in terms of AGB, BGB and TB. However, the R/S value was similar in plants that germinated in autumn and spring. The slope of regression relationship between AGB and BGB differed significantly among the three plant life forms. These results support different biomass allocation hypotheses. Specifically, at the individual level, the AGB and BGB partitioning supports the allometric hypothesis for ephemeroid and annual plants and the isometric hypothesis for ephemeral plants.展开更多
In this article, the author presents some results of the isometric linear extension from some spheres in the finite dimensional space s（n）. Moreover, the author presents the representation for the onto isometric map...In this article, the author presents some results of the isometric linear extension from some spheres in the finite dimensional space s（n）. Moreover, the author presents the representation for the onto isometric mappings in the space s. It is obtained that if V is a surjective isometry from the space s onto s with V（0） = 0, then V must be real linear.展开更多
In this paper, we study the extension of isometries between the unit spheres of complex Banach spaces lp（Γ） and lp（△）（p 〉1）. We first derive the representation of isometries between the unit spheres of comple...In this paper, we study the extension of isometries between the unit spheres of complex Banach spaces lp（Γ） and lp（△）（p 〉1）. We first derive the representation of isometries between the unit spheres of complex Banach spaces lp（Γ） and lp（△）. Then we arrive at a conclusion that any surjective isometry between the unit spheres of complex Banach spaces lp（Γ）and lp（△） can be extended to be a linear isometry on the whole space.展开更多
The neuromuscular junction becomes progressively less receptive to regenerating axons if nerve repair is delayed for a long period of time. It is difficult to ascertain the denervated muscle＇s residual receptivity by...The neuromuscular junction becomes progressively less receptive to regenerating axons if nerve repair is delayed for a long period of time. It is difficult to ascertain the denervated muscle＇s residual receptivity by time alone. Other sensitive markers that closely correlate with the extent of denervation should be found. After a denervated muscle develops a fibrillation potential, muscle fiber conduction velocity, muscle fiber diameter, muscle wet weight, and maximal isometric force all decrease; remodeling increases neuromuscular junction fragmentation and plantar area, and expression of myogenesis-related genes is initially up-regulated and then down-regulated. All these changes correlate with both the time course and degree of denervation. The nature and time course of these denervation changes in muscle are reviewed from the literature to explore their roles in assessing both the degree of detrimental changes and the potential success of a nerve repair. Fibrillation potential amplitude, muscle fiber conduction velocity, muscle fiber diameter, mRNA expression levels of myogenic regulatory factors and nicotinic acetylcholine receptor could all reflect the severity and length of denervation and the receptiveness of denervated muscle to regenerating axons, which could possibly offer an important clue for surgical choices and predict the outcomes of delayed nerve repair.展开更多
Some problems connect ed with production of new light-weight filler type are considered for sandwich layers. Constructively, the filler is the folded structure that can be developed on a plane. This feature makes it...Some problems connect ed with production of new light-weight filler type are considered for sandwich layers. Constructively, the filler is the folded structure that can be developed on a plane. This feature makes it possible to produce the filler by isometric t ransformation of thin sheet through local bending without material stretching.Th e main difficulty is that the bending must be carried out along all lines of com plex-shaped marking-out at a time. The problem of shaping can be solved by use of the original shaping device that can be transformed in operation. The herein -presented technology of production makes it possible to fabricate parts with d eep relief using a wide gamut of different materials even as the thin-sheet met al alloys and paper.展开更多
We calculated a self-thinning exponent of 1.05 for tree mass using the 3/2 power equation in 93 Cunninghamia lanceolata plots.According to Weller’s allometric model,the self-thinning exponent for tree mass was calcul...We calculated a self-thinning exponent of 1.05 for tree mass using the 3/2 power equation in 93 Cunninghamia lanceolata plots.According to Weller’s allometric model,the self-thinning exponent for tree mass was calculated as 1.28 from the allometric exponents h and d.The both self-thinning exponents were significantly lower than 3/2.The self-thinning exponent of organs was estimated to be 1.42 for stems,0.93 for branches,0.96 for leaves,1.35 for roots and 1.28 for shoots,respectively.The self-thinning exponent of stem mass was not significantly different from 3/2,whereas thinning exponents of trees,branches,leaves and roots were significantly lower than 3/2.The stand leaf mass and stand branch mass were constant regardless of the stand density.The scaling relations among branch,leaf,stem,root and shoot mass（MB,ML,MS,MR and MA,respectively） showed that MB and ML scaled as the3/4 power of MS,whereas MS or MA scaled isometrically with respect to MR.展开更多
Foliar C/N stoichiometry is an indicator of geochemical cycling in forest ecosystems,but the driving changes for its response to urbanization at the wide scale is not clear.In this study,data on tree-leaf C and N stoi...Foliar C/N stoichiometry is an indicator of geochemical cycling in forest ecosystems,but the driving changes for its response to urbanization at the wide scale is not clear.In this study,data on tree-leaf C and N stoichiometry were collected in papers from across 105 tree species from 82 genera and 46 families.The foliar C/N of urban forest trees varied among different climate zones and tree taxonomic variation and tended to be higher in trees of urban forests near the equator and in eastern regions,mainly driven by lowered foliar N concentration.Neither the foliar C concentration nor foliar C/N for trees of urban forests was statistically higher than those of rural forests.For variation by taxonomic classification,C_4 species Amaranthus retroflexus and Chenopodium ambrosoides(Amaranthaceae) had lower foliar C/N than did other species and families.Myrsine guianensis(Primulaceae) and Myconia fallax(Asteraceae) had the highest foliar C/N.Therefore,urbanization has not caused a significant response in forest trees for foliar C/N.The change in foliar N concentration was globally the main force driving of the differences in foliar C/N for most tree species in urban forests.More work is needed on foliar C/N in trees at cities in polar regions and the Southern Hemisphere.展开更多
Haberl and Ludwig introduced the L_p-intersection body I_pK for an originsymmetric star body K in R^n,where p < 1 and p ≠ 0.In this paper,we consider the Busemann-Petty's problem for L_p-intersection bodies I_...Haberl and Ludwig introduced the L_p-intersection body I_pK for an originsymmetric star body K in R^n,where p < 1 and p ≠ 0.In this paper,we consider the Busemann-Petty's problem for L_p-intersection bodies I_pK and I_pL.That is,whether I_pK ■ IpL implies Vol_n(K) ≤ Vol_n(L).We obtain that for two origin-symmetric star bodies K and L in R^n,such that(R^n,||·||K) embeds in L_p and I_pK ■ IpL,then vol_n(K) ≤ vol_n(L) for 0 < p < 1 and vol_n(K) ≥ vol_n(L) for p < 0.展开更多
Skeletal muscle stiffness is altered after spinal cord injury(SCI).Assessing muscle stiffness is essential for rehabilitation and pharmaceutical interventions design after SCI.The study used magnetic resonance elastog...Skeletal muscle stiffness is altered after spinal cord injury(SCI).Assessing muscle stiffness is essential for rehabilitation and pharmaceutical interventions design after SCI.The study used magnetic resonance elastography to assess the changes in stiffness after chronic SCI compared to matched able-bodied controls and determine its association with muscle size,spasticity,and peak torque in persons with SCI.Previous studies examined the association between muscle stiffness and spasticity,however,we are unaware of other studies that examined the effects of muscle composition on stiffness after SCI.Ten participants(one female)with chronic SCI and eight(one female)matched able-bodied controls participated in this cross-sectional study.Magnetic resonance elastography was utilized to monitor stiffness derived from shear waves propagation.Modified Ashworth scale was used to evaluate spasticity scores in a blinded fashion.Peak isometric and isokinetic torques were measured using a biodex dynamometer.Stiffness values were non-significantly lower(12.5%;P=0.3)in the SCI group compared to able-bodied controls.Moreover,stiffness was positively related to vastus lateralis whole muscle cross-sectional area(CSA)(r2=0.64,P<0.005)and vastus lateralis absolute muscle CSA after accounting for intramuscular fat(r2=0.78,P<0.0007).Stiffness was also positively correlated to both isometric(r2=0.55-0.57,P<0.05)and isokinetic peak(r2=0.46-0.48,P<0.05)torques.Our results suggest that larger clinical trial is warranted to confirm the preliminary findings that muscle stiffness is altered after SCI compared to healthy controls.Stiffness appeared to be influenced by infiltration of intramuscular fat and modestly by the spasticity of the paralyzed muscles.The preliminary data indicated that the relationship between muscle stiffness and peak torque is not altered with changing the frequency of pulses or angular velocities.All study procedures were approved by the Institutional Review Board at the Hunter Holmes McGuire VA Medical Center,USA(IRB#:02314)on May 3,2017.展开更多
In this article, we prove that an into 1-Lipschitz mapping from the unit sphere of a Hilbert space to the unit sphere of an arbitrary normed space, which under some conditions, can be extended to be a linear isometry ...In this article, we prove that an into 1-Lipschitz mapping from the unit sphere of a Hilbert space to the unit sphere of an arbitrary normed space, which under some conditions, can be extended to be a linear isometry on the whole space.展开更多
This article presents a novel method to prove that： let E be an AM-space and if dim E ≥ 3, then there does not exist any odd subtractive.isometric mapping from the unit sphere S（E） into S[L（Ω, μ）]. In particul...This article presents a novel method to prove that： let E be an AM-space and if dim E ≥ 3, then there does not exist any odd subtractive.isometric mapping from the unit sphere S（E） into S[L（Ω, μ）]. In particular, there does not exist any real linear isometry from E into L（Ω, μ）.展开更多
文摘Osteoarthritis of knee is a common problem in the elderly population worldwide. Physical therapy has been shown to be useful in decreasing pain and increasing mobility in this population. The aim of this study was to study the effectiveness of slow reversal hold and isometric exercise techniques in reducing pain, increasing muscle strength, and increasing range of motion for knee flexion in patients with osteoarthritis of knee. The other aim of this study was to compare the relative effectiveness of these two interventions. 60 subjects participated in this study and were randomly assigned either to the slow reversal hold group (n = 30) or, to the isometrics exercise group (n = 30). All subjects performed their respective exercises for 3 weeks. Pain scores using the visual analog scale, muscle strength using manual muscle testing of quadriceps and hamstrings, and range of motion (ROM) for knee flexion using a goniometer were recorded both pre-treatment and post-treatment for both left and right knees. Both the interventions showed a significant decrease in pain scores, an increase in muscle strength, as well as an increase in the ROM. However, ROM was significantly increased in the slow reversal hold group as compared to the isometrics group in both knees. It was concluded that both exercise techniques could be useful in patients with osteoarthritis of knee for decreasing pain and increasing muscle strength. Slow reversal hold technique might be a better technique than isometrics for increasing ROM for knee flexion.
文摘Increased neck strength has been linked to a potential decrease in traumatic brain injuries(TBI).The purpose was to determine the efficacy of a neck-strengthening protocol using a novel neck-strengthening device to increase isometric neck strength and rate of force development(RFD).Utilizing self-generated centripetal force,participants trained for 14 weeks.A linear mixed model was used to analyze the relationship between post-assessment measurements and pre-assessments measurements,while accounting for repeated measure random effect at the individual level,and a regular random error term.RFD values were 4.344 times higher in the clockwise direction and 5.978 times higher in the counterclockwise direction when comparing pre and post assessment measurements.Isometric neck strength increased significantly(p<0.05)in the cervical extension(p=0.010)and left lateral flexion(p=0.009)directions.The results can be used in strength training and clinical settings to potentially reduce the incidence of TBI.
文摘Low back pain(LPB)is a common and impactful health concern globally,affecting individuals across various demographics and imposing a significant burden on the health care system.Nonspecific chronic LBP(NCLBP),charac-terized as pain lasting over 12 weeks without an identifiable cause,leads to notable functional limitations and reduced quality of life.Traditional rehabil-itation programs,often focusing on dynamic exercises for lumbar strengthening,typically do not target the deep stabilizing muscles crucial for lumbar support and effective recovery.Multi-angular isometric lumbar exercise(MAILE)offers a low-impact method for strengthening lumbar stabilizers through multi-angular isometric contractions,reducing risks from dynamic movements.This article examines MAILE’s potential in addressing motor control dysfunctions in NCLBP,highlighting studies on lumbar muscle activation,core stability,and isometric exercises.The article explores the prevalence and socioeconomic impact of NCLBP in the Middle East,highlighting the need for affordable treatment options in areas like Qatar and Saudi Arabia.This article aims to validate the efficacy of MAILE in reducing pain,enhancing mobility,and improving lumbar stability,offering a valuable option for NCLBP management.Future research should focus on large-scale clinical trials to substantiate these findings and guide clinical practice.
基金Supported by the by Key R&D Program of Gansu Province(No.23YFGA0063)the Key Talent Project of Gansu Province(No.2024RCXM57,2024RCXM22)the Major Science and Technology Special Program of Gansu Province(No.25ZYJA037).
文摘Precise traffic flow forecasting is essential for mitigating urban traffic congestion.However,it is difficult for existing methods to adequately capture the dynamic spatio-temporal characteristics and multiscale temporal dependencies of traffic flow.A traffic flow prediction model with multiscale temporal awareness and graph diffusion attention networks(MT-GDAN)is proposed to address these issues.Specifically,a graph diffusion attention module is constructed,which dynamically adjusts and calculates the weights of neighboring nodes in the graph structure using a random graph attention network(GAT)and captures the spatial characteristics of hidden nodes through an adaptive adjacency matrix,thus better exploiting the dynamic spatio-temporal properties of traffic flow.Secondly,a multiscale isometric convolutional network and bi-level routing attention are used to construct a multiscale temporal awareness module.The former extracts local information of traffic flow segments by convolution with different sizes of convolution kernels and then introduces isometric convolution to obtain the global temporal relationship between local features of traffic flow segments;the latter filters irrelevant spatio-temporal features at a coarse regional level and focuses locally on key points to more accurately capture the multiscale temporal dependencies of traffic flows.Experimental results reveal that the MT-GDAN model surpasses the mainstream baseline model in terms of forecasting accuracy and exhibits good prediction performance.
文摘Abstract This paper gencralizes the result about linear isometries of S~ spaces given by W.P.Novinger and D.M.Oberlin[2]for the unite dise of C to the bounded symmetric domains of C^n
基金Supported by A grant from E-Da Hospital (in part)
文摘AIM： To investigate the role of opioid p-receptor subtype in opiate-induced constipation （OIC）.METHODS： The effect of Ioperamide on intestinal transit was investigated in mice. Ileum strips were isolated from 12-wk-old male BALB/c mice for identification of isometric tension. The ileum strips were precontracted with 1 μmol/L acetylcholine （ACh）. Then, decrease in muscle tone （relaxation） was characterized after cumu- lative administration of 0.1-10μ~mol/L Ioperamide into the organ bath, for a concentration-dependent study. Specific blockers or antagonists were used for pretreat- ment to compare the changes in Ioperamide-induced relaxation.RESULTS： In addition to the delay in intestinal transit, Ioperamide produced a marked relaxation in isolated ileum precontracted with ACh, in a dose-dependent manner. This relaxation was abolished by cyprodime,a selective opioid p-receptor antagonist, but not modified by naloxonazine at a dose sufficient to block opioid μ-1 receptors. Also, treatment with opioid μ-1 receptor agonist failed to modify the muscle tone. Moreover, the relaxation by Ioperamide was attenuated by glibenclamide at a dose sufficient to block ATP-sensitive K^＋ （KATP） channels, and by protein kinase A （PKA） inhibitor, but was enhanced by an inhibitor of phosphodiesterase for cyclic adenosine monophosphate （cAMP）.CONCLUSION： Loperamide induces intestinal relaxa- tion by activation of opioid μ-2 receptors via the cAMP- PKA pathway to open KATp channels, relates to OIC.
基金Supported by the National Natural Science Foundation of China(No.81222021 and No.31011130042)the National Key Technology R&D Program of the Ministry of Science and Technology of China(No.2012BAI34B02)
文摘In order to detect and assess the muscle fatigue state with the surface electromyography(sEMG) characteristic parameters,this paper carried out a series of isometric contraction experiments to induce the fatigue on the forearm muscles from four subjects,and recorded the sEMG signals of the flexor carpi ulnaris.sEMG's median frequency(MDF) and mean frequency(MF) were extracted by short term Fourier transform(STFT),and the root mean square(RMS) of wavelet coefficients in the frequency band of 5—45 Hz was obtained by continuous wavelet transform(CWT).The results demonstrate that both MDF and MF show downward trends within 1 min; however,RMS shows an upward trend within the same time.The three parameters are closely correlated with absolute values of mean correlation coefficients greater than 0.8.It is suggested that the three parameters above can be used as reliable indicators to evaluate the level of muscle fatigue during isometric contractions.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA20020101)the National Natural Science Foundation of China(31400394)
文摘Biomass allocation patterns among plant species are related to their adaptive ecological strategies. Ephemeral, ephemeroid and annual plant life forms represent three typical growth strategies of plants that grow in autumn and early spring in the cold deserts of China. These plants play an important role in reducing wind velocity in the desert areas. However, despite numerous studies, the strategies of biomass allocation among plant species with these three life forms remain contentious. In this study, we conducted a preliminary quadrat study during 2014–2016 in the southern part of the Gurbantunggut Desert, China, to investigate the allocation patterns of above-ground biomass(AGB) and below-ground biomass(BGB) at the individual level in 17 ephemeral, 3 ephemeroid and 4 annual plant species. Since ephemeral plants can germinate in autumn, we also compared biomass allocation patterns between plants that germinated in autumn 2015 and spring 2016 for 4 common ephemeral species. The healthy mature individual plants of each species were sampled and the AGB, BGB, total biomass(TB), leaf mass ratio(LMR) and root/shoot ratio(R/S) were calculated for 201 sample quadrats in the study area. We also studied the relationships between AGB and BGB of plants with the three different life forms(ephemeral, ephemeroid and annual). The mean AGB values of ephemeral, ephemeroid and annual plants were 0.806, 3.759 and 1.546 g/plant, respectively, and the mean BGB values were 0.106, 4.996 and 0.166 g/plant, respectively. The mean R/S value was significantly higher in ephemeroid plants(1.675) than in ephemeral(0.154) and annual(0.147) plants. The mean LMR was the highest in annual plants, followed by ephemeroid plants and ephemeral plants, reflecting the fact that annual plants allocate more biomass to leaves, associated with their longer life span. Biomass of ephemeral plants that germinated in autumn was significantly higher than those of corresponding plants that germinated in spring in terms of AGB, BGB and TB. However, the R/S value was similar in plants that germinated in autumn and spring. The slope of regression relationship between AGB and BGB differed significantly among the three plant life forms. These results support different biomass allocation hypotheses. Specifically, at the individual level, the AGB and BGB partitioning supports the allometric hypothesis for ephemeroid and annual plants and the isometric hypothesis for ephemeral plants.
基金Supported by the National Science Foundation of China (10571090) The Research Fund for the Doctoral Program of Higher Education (20010055013)
文摘In this article, the author presents some results of the isometric linear extension from some spheres in the finite dimensional space s（n）. Moreover, the author presents the representation for the onto isometric mappings in the space s. It is obtained that if V is a surjective isometry from the space s onto s with V（0） = 0, then V must be real linear.
基金supported by Higher Educational Science and Technology Program Foundation of Shandong Province(J11LA02)Young and Middle-Aged Scientists Research Foundation of Shandong Province(BS2010SF004)Higher Educational Science and Technology Program Foundation of Shandong Province(J10LA53)
文摘In this paper, we study the extension of isometries between the unit spheres of complex Banach spaces lp（Γ） and lp（△）（p 〉1）. We first derive the representation of isometries between the unit spheres of complex Banach spaces lp（Γ） and lp（△）. Then we arrive at a conclusion that any surjective isometry between the unit spheres of complex Banach spaces lp（Γ）and lp（△） can be extended to be a linear isometry on the whole space.
基金sponsored by the Armed Forces Institute of Regenerative Medicine award number W81XWH-08-2-0034supported by the Sundt Fellowship fund,Department of Neurologic Surgery,Mayo Clinic,USA
文摘The neuromuscular junction becomes progressively less receptive to regenerating axons if nerve repair is delayed for a long period of time. It is difficult to ascertain the denervated muscle＇s residual receptivity by time alone. Other sensitive markers that closely correlate with the extent of denervation should be found. After a denervated muscle develops a fibrillation potential, muscle fiber conduction velocity, muscle fiber diameter, muscle wet weight, and maximal isometric force all decrease; remodeling increases neuromuscular junction fragmentation and plantar area, and expression of myogenesis-related genes is initially up-regulated and then down-regulated. All these changes correlate with both the time course and degree of denervation. The nature and time course of these denervation changes in muscle are reviewed from the literature to explore their roles in assessing both the degree of detrimental changes and the potential success of a nerve repair. Fibrillation potential amplitude, muscle fiber conduction velocity, muscle fiber diameter, mRNA expression levels of myogenic regulatory factors and nicotinic acetylcholine receptor could all reflect the severity and length of denervation and the receptiveness of denervated muscle to regenerating axons, which could possibly offer an important clue for surgical choices and predict the outcomes of delayed nerve repair.
文摘Some problems connect ed with production of new light-weight filler type are considered for sandwich layers. Constructively, the filler is the folded structure that can be developed on a plane. This feature makes it possible to produce the filler by isometric t ransformation of thin sheet through local bending without material stretching.Th e main difficulty is that the bending must be carried out along all lines of com plex-shaped marking-out at a time. The problem of shaping can be solved by use of the original shaping device that can be transformed in operation. The herein -presented technology of production makes it possible to fabricate parts with d eep relief using a wide gamut of different materials even as the thin-sheet met al alloys and paper.
基金supported by Foundation of Guangdong Forestry Bureau (Nos.4400-F11031,4400-F11055)
文摘We calculated a self-thinning exponent of 1.05 for tree mass using the 3/2 power equation in 93 Cunninghamia lanceolata plots.According to Weller’s allometric model,the self-thinning exponent for tree mass was calculated as 1.28 from the allometric exponents h and d.The both self-thinning exponents were significantly lower than 3/2.The self-thinning exponent of organs was estimated to be 1.42 for stems,0.93 for branches,0.96 for leaves,1.35 for roots and 1.28 for shoots,respectively.The self-thinning exponent of stem mass was not significantly different from 3/2,whereas thinning exponents of trees,branches,leaves and roots were significantly lower than 3/2.The stand leaf mass and stand branch mass were constant regardless of the stand density.The scaling relations among branch,leaf,stem,root and shoot mass（MB,ML,MS,MR and MA,respectively） showed that MB and ML scaled as the3/4 power of MS,whereas MS or MA scaled isometrically with respect to MR.
基金supported by National Natural Science Foundation of China (Grant Nos.41971122,41861017)Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No.XDA23070503)+1 种基金National Key Research and Development Program of China (Grant No.2016YFC0500300)the Scholarship of Chinese Academy of Sciences for Overseas Study。
文摘Foliar C/N stoichiometry is an indicator of geochemical cycling in forest ecosystems,but the driving changes for its response to urbanization at the wide scale is not clear.In this study,data on tree-leaf C and N stoichiometry were collected in papers from across 105 tree species from 82 genera and 46 families.The foliar C/N of urban forest trees varied among different climate zones and tree taxonomic variation and tended to be higher in trees of urban forests near the equator and in eastern regions,mainly driven by lowered foliar N concentration.Neither the foliar C concentration nor foliar C/N for trees of urban forests was statistically higher than those of rural forests.For variation by taxonomic classification,C_4 species Amaranthus retroflexus and Chenopodium ambrosoides(Amaranthaceae) had lower foliar C/N than did other species and families.Myrsine guianensis(Primulaceae) and Myconia fallax(Asteraceae) had the highest foliar C/N.Therefore,urbanization has not caused a significant response in forest trees for foliar C/N.The change in foliar N concentration was globally the main force driving of the differences in foliar C/N for most tree species in urban forests.More work is needed on foliar C/N in trees at cities in polar regions and the Southern Hemisphere.
基金Supported by the NNSF of China(11161019)Supported by the Foundation of the Education Department of Gansu Province(1009B-09)
文摘Haberl and Ludwig introduced the L_p-intersection body I_pK for an originsymmetric star body K in R^n,where p < 1 and p ≠ 0.In this paper,we consider the Busemann-Petty's problem for L_p-intersection bodies I_pK and I_pL.That is,whether I_pK ■ IpL implies Vol_n(K) ≤ Vol_n(L).We obtain that for two origin-symmetric star bodies K and L in R^n,such that(R^n,||·||K) embeds in L_p and I_pK ■ IpL,then vol_n(K) ≤ vol_n(L) for 0 < p < 1 and vol_n(K) ≥ vol_n(L) for p < 0.
文摘Skeletal muscle stiffness is altered after spinal cord injury(SCI).Assessing muscle stiffness is essential for rehabilitation and pharmaceutical interventions design after SCI.The study used magnetic resonance elastography to assess the changes in stiffness after chronic SCI compared to matched able-bodied controls and determine its association with muscle size,spasticity,and peak torque in persons with SCI.Previous studies examined the association between muscle stiffness and spasticity,however,we are unaware of other studies that examined the effects of muscle composition on stiffness after SCI.Ten participants(one female)with chronic SCI and eight(one female)matched able-bodied controls participated in this cross-sectional study.Magnetic resonance elastography was utilized to monitor stiffness derived from shear waves propagation.Modified Ashworth scale was used to evaluate spasticity scores in a blinded fashion.Peak isometric and isokinetic torques were measured using a biodex dynamometer.Stiffness values were non-significantly lower(12.5%;P=0.3)in the SCI group compared to able-bodied controls.Moreover,stiffness was positively related to vastus lateralis whole muscle cross-sectional area(CSA)(r2=0.64,P<0.005)and vastus lateralis absolute muscle CSA after accounting for intramuscular fat(r2=0.78,P<0.0007).Stiffness was also positively correlated to both isometric(r2=0.55-0.57,P<0.05)and isokinetic peak(r2=0.46-0.48,P<0.05)torques.Our results suggest that larger clinical trial is warranted to confirm the preliminary findings that muscle stiffness is altered after SCI compared to healthy controls.Stiffness appeared to be influenced by infiltration of intramuscular fat and modestly by the spasticity of the paralyzed muscles.The preliminary data indicated that the relationship between muscle stiffness and peak torque is not altered with changing the frequency of pulses or angular velocities.All study procedures were approved by the Institutional Review Board at the Hunter Holmes McGuire VA Medical Center,USA(IRB#:02314)on May 3,2017.
基金Supported by NSFC (10871101)the Doctoral Programme Foundation of Institution of Higher Education (20060055010)
文摘In this article, we prove that an into 1-Lipschitz mapping from the unit sphere of a Hilbert space to the unit sphere of an arbitrary normed space, which under some conditions, can be extended to be a linear isometry on the whole space.
基金This study is supported by the National Natural Science Foundation of China (10571090)the Research Fund for the Doctoral Program of Higher Education (20060055010)
文摘This article presents a novel method to prove that： let E be an AM-space and if dim E ≥ 3, then there does not exist any odd subtractive.isometric mapping from the unit sphere S（E） into S[L（Ω, μ）]. In particular, there does not exist any real linear isometry from E into L（Ω, μ）.
