With the development of the social economy and the rise of the national fitness campaign, the development of sports functional beverage has become a part of sports consumption. Sports functional beverage has significa...With the development of the social economy and the rise of the national fitness campaign, the development of sports functional beverage has become a part of sports consumption. Sports functional beverage has significant effect on improving athletic ability and fast recovery. But the inappropriate choice of beverage and drinking arrangements will cause irreparable damage to the body. Only the scientific and rational drinking, sports functional beverage will really play its whole function.展开更多
Gold Medals in Summer Qlympics Measures A 1) Program to develop junior athletes to top level 2) National Training Center 3) National Coach Academy B 1) Sports medicine and sciences(JISS) 2) Anti-doping 3) To hold inte...Gold Medals in Summer Qlympics Measures A 1) Program to develop junior athletes to top level 2) National Training Center 3) National Coach Academy B 1) Sports medicine and sciences(JISS) 2) Anti-doping 3) To hold international展开更多
The formation mechanism of methane (CH4) during coal evolution has been investigated by density functional theory (DFT) of quantum chemistry. Thermogenic gas, which is generated during the thermal evolution of med...The formation mechanism of methane (CH4) during coal evolution has been investigated by density functional theory (DFT) of quantum chemistry. Thermogenic gas, which is generated during the thermal evolution of medium rank coal, is the main source of coalbed methane (CBM). Ethylbenzene (A) and 6,7-dimethyl-5,6,7,8-tetrahydro-1-hydroxynaphthalene (B) have been used as model compounds to study the pyrolysis mechanism of highly volatile bituminous coal (R), according to the similarity of bond orders and bond lengths. All possible paths are designed for each model. It can be concluded that the activation energies for H-assisted paths are lower than others in the process of methane formation; an H radical attacking on β-C to yield CH4 is the dominant path for the formation of CH4 from highly volatile bituminous coal. In addition, the calculated results also reveal that the positions on which H radical attacks and to which intramolecular H migrates have effects on methyl cleavage.展开更多
In this paper we show that two significant phenomena of magnetospheric chorus emission can be explained by the participation of beam-like electron structures,created by Landau-resonant interaction with growing oblique...In this paper we show that two significant phenomena of magnetospheric chorus emission can be explained by the participation of beam-like electron structures,created by Landau-resonant interaction with growing oblique whistler waves.The first concerns the widely observed spectral gap near half the electron cyclotron frequency Ωe;the second is related to the observation of very obliquely propagating lower-band waves that cannot be directly generated by temperature anisotropy.Concerning the gap,kinetic dispersion theory reveals that interference of the beam-related cyclotron mode ω~Ωe-kVb with the conventional whistler mode leads to mode splitting and the appearance of a ’forbidden’ area in the ω-k space.Thereby the beam velocity appears as an essential parameter.It is directly related to the phase velocity of the most unstable whistler wave mode,which is close to VAe/2 for sufficiently hot electrons(VAe is the electron Alfven velocity).To clarify the second point,we show that Landau-resonant beams with Vb Vb<VAe/2,which arise in cold plasmas from unstable upper-band waves,are able to generate lower-band whistler mode waves at very oblique propagation(θ≥60°).Our studies demonstrate the important role of Landau-resonant electrons in nonlinear whistler wave generation in the magnetosphere.展开更多
Oxygen vacancy formation and migration in La0.9Sr0.1Ga0.8Mg0.2O3-5 (LSGM) with various crystal symmetries (cubic, rhombohedral, orthorhombic, and monoclinic) are studied by employing first-principles calculations ...Oxygen vacancy formation and migration in La0.9Sr0.1Ga0.8Mg0.2O3-5 (LSGM) with various crystal symmetries (cubic, rhombohedral, orthorhombic, and monoclinic) are studied by employing first-principles calculations based on density functional theory (DFT). It is shown that the cubic LSGM has the smallest band gap, oxygen vacancy formation energy, and migration barrier, while the other three structures give rise to much larger values for these quantities, implying the best oxygen ion conductivity of the cubic LSGM among the four crystal structures. In out calculations, one oxygen vacancy migration pathway is considered in the cubic and rhombohedral structures due to all the oxygen sites being equivalent in them, while two vacancy migration pathways with different migration barriers are found in the orthorhombic and monoclinic symmetries owing to the existence of nonequivalent O1 and 02 oxygen sites. The migration energies along the migration pathway linking the two 02 sites are obviously lower than those along the pathway linking the O1 and 02 sites. Considering the phase transitions at high temperatures, the results obtained in this paper can not only explain the experimentally observed different behaviours of the oxygen ionic conductivity of LSGM with different symmetries, but also predict the rational crystal structures of LSGM for solid oxide fuel cell applications.展开更多
The article presents the data of the assessment of the physical development and functional state of highly qualifiedgymnasts engaged in rhythmic gymnastics. It was found that high-skilled gymnasts have heterogeneity o...The article presents the data of the assessment of the physical development and functional state of highly qualifiedgymnasts engaged in rhythmic gymnastics. It was found that high-skilled gymnasts have heterogeneity ofsomatotypes determined according to the B. Heath-J. Carter scheme and heterogeneity of types of autonomousnervous regulation of heart rate variability, systolic, diastolic blood pressure and respiration, determined on thespiroarteriorhythmocardiograph device. Highly qualified gymnasts have vago- and normotonic types of regulationof heart rate variability;normal-sympathetic-and hypersympathicotonic types of regulation of the variability ofsystolic blood pressure and diastolic blood pressure, vagotonic type of regulation of the variability of the respiratoryrhythm. Statistically significant differences gymnasts, successful in the medal standings at the internationalcompetitions and gymnasts participating, but not in high prizes in competitions, consist in the ability to resistfatigue while performing strenuous mental work (differences were revealed in 10-letter “Mental performance” at aconstant speed (p > 0.0001), and 3-letter test (p > 0.001)), data stabilometric test “Target” indicator “Time stabilityon the left foot” (R > 0.039) with the advantage of a high performing gymnasts artists. Fleshed out the possibility ofusing the parameters of the morphofunctional state of gymnasts in training for the qualitative evaluation of thephysical development of gymnasts, evaluation set their sports uniforms indicated the possibility of developing thereference parameters of the morphofunctional status of gymnasts and recommendations on the frequency of thesurvey of morphological and functional status of gymnasts involved in rhythmic gymnastics.展开更多
With the widespread development of international sports events, more and more people pay attention to the international sports games by reading sports news or watching sports videos. Since English is the universal lan...With the widespread development of international sports events, more and more people pay attention to the international sports games by reading sports news or watching sports videos. Since English is the universal language, the news of these sports events is mostly reported in English. However,English sports news could bring some reading difficulties for Chinese readers. In the author's view, words are the basic elements of the English sports news language. It is of significance to study English sports news lexis. Under the guidance of Functional Equivalence Theory,this study attempts to explore the lexical features of English sports news and to analyze some useful lexical translation strategies. The results of the study show that Nida's Functional Equivalence Theory is applicable to the lexical translation of English sports news. It is recommended that translators follow Nida's equivalence theory during the translation.展开更多
The catalytic fast pyrolysis of cellulose impregnated with phosphoric acid (H3PO4) offers a promising method for the selective production of levoglucosenone (LGO),a valuable anhydrosugar product.However,the fundamenta...The catalytic fast pyrolysis of cellulose impregnated with phosphoric acid (H3PO4) offers a promising method for the selective production of levoglucosenone (LGO),a valuable anhydrosugar product.However,the fundamental mechanism for selective LGO formation is unclear.Herein,quantum chemistry calculations and catalytic fast pyrolysis experiments were performed to reveal the formation mechanism of LGO in H3PO4-catalyzed cellulose pyrolysis.H3PO4 significantly decreased the energy barriers of the pyrolytic reactions and altered the competitiveness of the LGO formation pathways,promoting LGO formation.Through different pathways in the non-catalytic and H3P04-catalyzed conditions,LGO is mainly produced from the primary decomposition of glucose units of cellulose and secondary conversion of levoglucosan.The major catalytic formation pathways of LGO comprise similar reactions,with dehydration at the 3-OH+2-H site as the rate-determining step.Importantly,secondary conversion of 1,4;3,6-dianhydro-α-D-glucopyranose is not feasible for LGO formation,in contrast to previous reports.In addition,a high degree of polymerization is beneficial for the selectivity of LGO formation in the catalytic process,because the glycosidic bond is important for the formation of the bicyclic structure (1,5-and1,6-acetal rings).展开更多
An effective structural codoping approach is proposed to modify the photoelectrochemical (PEC) properties of anatase TiO2 by being doped with nonmetal (N or/and C) and transition metal (Re) elements. The electro...An effective structural codoping approach is proposed to modify the photoelectrochemical (PEC) properties of anatase TiO2 by being doped with nonmetal (N or/and C) and transition metal (Re) elements. The electronic structures and for- mation energies of different doped systems are investigated using spin-polarized density functional theory. We find that (C, Re) doped TiO2, with a low formation energy and a large binding energy, reduces the band gap to a large extent, thus it could contribute to the significant enhancement of the photocatalytic activity in the visible-light region. It should be pointed out that, to be successful, the proper proportion of the dopants C and Re should be controlled, so that reasonable PEC properties can be achieved.展开更多
Based on density functional theory, using the scheme of the linearized augmented plane wave and the improved local orbital (APW+lo), this paper analyses and calculates the lattice parameters, formation energy and m...Based on density functional theory, using the scheme of the linearized augmented plane wave and the improved local orbital (APW+lo), this paper analyses and calculates the lattice parameters, formation energy and magnetism of the rare-earth permanent magnetic materials YFe12-xCrx (x = 0 - 5). The stabilization effect and the possible positions of the substituted atom Cr are analysed. Magnetic moments for the system and the atoms are obtained.展开更多
The theoretical calculation of LaNi4Co, in which Co substituted for Ni at various sites, was performed by adopting the method of total energy based on the Density Functional Theory. The augmented plane wave function w...The theoretical calculation of LaNi4Co, in which Co substituted for Ni at various sites, was performed by adopting the method of total energy based on the Density Functional Theory. The augmented plane wave function was selected as a basis set in combination with Ultra-soft Pseudopotential technology. The geometry of LaNi5 was optimized and the parameters and properties of the structure were given. The theoretical results accord well with experiments. This method provides a theoretical approach for the structure prediction of such alloy. The calculations of total energy, electronic density of states and Mulliken population of LaNi4Co were carried out. The electronic structure of LaNi4Co and the change of the electronic structure due to the Co-substitution in LaNi5 alloy were analyzed from the calculated results. The stability of the alloy in which Ni was partially substituted by Co at various sites was compared and the factors controlling stability were discussed. The theoretical value of formation heat was calculated.展开更多
In this paper, the thermodynamic parameters are calculated for all gaseous Poly Chlorinat Dibenzo-p-dioxins (PCDDs) using the Density Functional Theory (DFF) method and both the enthalpy of formation (ΔfH^0) an...In this paper, the thermodynamic parameters are calculated for all gaseous Poly Chlorinat Dibenzo-p-dioxins (PCDDs) using the Density Functional Theory (DFF) method and both the enthalpy of formation (ΔfH^0) and Gibbs free energy of formation (Δf G^0) are derived, from which the order of stability of individual congeners is then predicted. All these properties, together with the calculated entropies ( S^0) and heat capacities ( Cp), are presented as a function of the number of chlorine atoms in the various PCDD molecules. The accuracy of the method used here, is evaluated by comparing the thermodynamic parameters of gaseous chlorobenzenes with experimental values collected from literature.展开更多
Reservoir connectivity is a critical issue in the process of oil-gas exploration and development. According to the theory of fluid mechanics and the achievements of many scholars, a connected reservoir coincides with ...Reservoir connectivity is a critical issue in the process of oil-gas exploration and development. According to the theory of fluid mechanics and the achievements of many scholars, a connected reservoir coincides with a unified formation pressure system;there is a linear relationship between formation pressure and depth in normal pressure system reservoir. However, in high-permeability or multi-phase fluid reservoirs, this method has poor applicability and limitations. Through theoretical analysis and formula derivation, a new method for judging the connectivity of normal pressure reservoirs is found, that is, the inverse proportional function relationship between the pressure coefficient and the depth. In this paper, the relationship between the pressure system and the inverse proportional function has been verified. The function of the same pressure system is unique, monotonic, and has unified asymptote and symmetry axis and vice versa. Examples show that the inverse proportional function is more accurate and reliable for judging reservoir connectivity than the linear function.展开更多
The human brain contains an estimated 100 billion neurons that must be systematically organized into functional neural circuits for it to function properly.These circuits range from short-range local signaling network...The human brain contains an estimated 100 billion neurons that must be systematically organized into functional neural circuits for it to function properly.These circuits range from short-range local signaling networks between neighboring neurons to long-range networks formed between various brain regions.Compelling converging evidence indicates that alterations in neural circuits arising from abnormalities during early neuronal development or neurodegeneration contribute significantly to the etiology of neurological disorders.Supporting this notion,efforts to identify genetic causes of these disorders have uncovered an over-representation of genes encoding proteins involved in the processes of neuronal differentiation,maturation,synaptogenesis and synaptic function.Fasciculation and elongation protein zeta-1,a Kinesin-1 adapter,has emerged as a key central player involved in many of these processes.Fasciculation and elongation protein zeta-1-dependent transport of synaptic cargoes and mitochondria is essential for neuronal development and synapse establishment.Furthermore,it acts downstream of guidance cue pathways to regulate axo-dendritic development.Significantly,perturbing its function causes abnormalities in neuronal development and synapse formation both in the brain as well as the peripheral nervous system.Mutations and deletions of the fasciculation and elongation protein zeta-1 gene are linked to neurodevelopmental disorders.Moreover,altered phosphorylation of the protein contributes to neurodegenerative disorders.Together,these findings strongly implicate the importance of fasciculation and elongation protein zeta-1 in the establishment of neuronal circuits and its maintenance.展开更多
Using Chandra ACIS S3 data we studied the X-ray properties of low-and highmass X-ray binary populations in the nearby spiral galaxy NGC 5055. A total of 43 X-ray point sources were detected within two effective radii,...Using Chandra ACIS S3 data we studied the X-ray properties of low-and highmass X-ray binary populations in the nearby spiral galaxy NGC 5055. A total of 43 X-ray point sources were detected within two effective radii, with 31 sources located on the disk and the rest 12 sources in the bulge. The resolved point sources dominate the X-ray emission of the galaxy, accounting for about 80% of the total counts in 0.3-10keV. From spectral fittings we calculated the 0.3-10.0keV luminosities of all the detected X-ray point sources and found that they span a wide range from a few times 10^37 erg s^-1 to over 10^39 erg s^-1. After compensating for incompleteness at the low luminosity end, we found that the corrected XLF of the bulge population is well fitted with a broken power-law with a break at 1.57-0.20^+0.21 1038 erg s^-1, while the profile of the disk population's XLF agrees with a single powerlaw distribution of slope 0 9-0.06^+0.07 The disk population is significantly richer at ≥ 2 × 10^38 erg s^- 1 than the bulge population, indicating that the disk may have undergone relatively recent, strong starbursts that significantly increased the HMXB population, although ongoing starbursts are also observed in the nuclear region. Similar XLF profiles of the bulge and disk populations were found in M81. However, in most other spiral galaxies different patterns of spatial variation of the XLF profiles from the bulge to the disk have been observed, indicating that the star formation and evolution history may be more complex than we have expected.展开更多
For the case where the multivariate normal population does not have null correlations, we give the exact expression of the distribution of the sample matrix of correlations R, with the sample variances acting as param...For the case where the multivariate normal population does not have null correlations, we give the exact expression of the distribution of the sample matrix of correlations R, with the sample variances acting as parameters. Also, the distribution of its determinant is established in terms of Meijer G-functions in the null-correlation case. Several numerical examples are given, and applications to the concept of system de- pendence in Reliability Theory are presented.展开更多
In this paper, the strain energy function proposed by Shang and Cheng was generalized by introducing a nonlinear term. Void formation and growth in the interior of a sphere composed of compressible hyper-elastic mater...In this paper, the strain energy function proposed by Shang and Cheng was generalized by introducing a nonlinear term. Void formation and growth in the interior of a sphere composed of compressible hyper-elastic material, subjected to a prescribed uniform displacement, was examined. A parametric cavitated bifurcation solution for the radial deformed function was obtained. Stability of the solution of the cavitated bifurcation equation was discussed. With the appearance of a cavity, an interesting feature of the radial deformation near the deformed cavity wall is the transition from extension to compression.展开更多
An extrusion-ploughing process was presented to fabricate the integral fin function-surface. Cutting edge inclination angle and rake angle can be calculated from the tool’s geometry relationship. The description of f...An extrusion-ploughing process was presented to fabricate the integral fin function-surface. Cutting edge inclination angle and rake angle can be calculated from the tool’s geometry relationship. The description of fins’ geometry characters was standardized. The experiments show that, when the middle cutting edge’s inclination angle η is less than 35°, continuous fin will come out; when η is between 35° and 55°, the fins will be saw-tooth ones, and the fins will be torn when this angle is above 55°; when the extrusion angle θ is between 60° and 150°, the fins will appear, or else, the fins will be torn into chips from the base. Forming angle and clearance angle have little effect on fin’s formation. For continuous fin, its height is close to cutting depth when it is small, but it will become approximately constant as cutting depth grows; for saw-tooth fins, the width, the height, as well as the clearance will increase with the increase of cutting depth, but the increment of clearance is small; neither for continuous fin, nor for saw-tooth ones, cutting velocity has little influence on their structure parameters.展开更多
BACKGROUND In high-intensity sports like golf,knee joints are prone to injury,leading to pain,limited mobility,and decreased quality of life.Traditional treatment methods typically involve rehabilitation exercises,but...BACKGROUND In high-intensity sports like golf,knee joints are prone to injury,leading to pain,limited mobility,and decreased quality of life.Traditional treatment methods typically involve rehabilitation exercises,but their effectiveness may be limited.In recent years,sodium hyaluronate has emerged as a widely used biomedical material in the treatment of joint diseases.AIM To explore the effect of sodium hyaluronate combined with rehabilitation training on pain degree,flexion range of motion and motor function of knee joint injured by golf.METHODS Eighty patients with knee joint injury caused by golf were randomly divided into control(group B)and observation group(group A).The group B was treated with rehabilitation training,and the group A was treated with sodium hyaluronate combined with rehabilitation training.The clinical efficacy,range of motion and function of knee joint,quality of life and inflammatory factors were compared.RESULTS The excellent and good rate of rehabilitation in the group A was raised than group B.At 6 weeks and 3 months after treatment,the range of motion of the two groups was raised than that before treatment,and that of the group A was raised than group B.After treatment,the scores of Lysholm and International Knee Documentation Committee(IKDC)in the group A were raised,and those in the group A were raised than group B.The VAS score of the two groups was reduced than that of the group B,and the SF-36 score of the group A was reduced than group B.The interleukin(IL)-1β,IL-8 and tumor necrosis factor-αin the two groups were reduced,and those in the group A were reduced than group B.CONCLUSION Sodium hyaluronate combined with rehabilitation training has a good clinical effect in the treatment of patients with knee joint injury caused by golf,which relieve pain,maintain knee joint function and improve patients'life quality.展开更多
Computations by density functional theory(DFT) method are performed on a series of di-1H-1,3,4-triazole derivatives with different substituents and linkages. The heat of formation(HOF) is predicted by the designed iso...Computations by density functional theory(DFT) method are performed on a series of di-1H-1,3,4-triazole derivatives with different substituents and linkages. The heat of formation(HOF) is predicted by the designed isodesmic reactions. The predicted results reveal that eN 3and eN ]Ne groups are effective structural units for increasing the HOF values of the di-1H-1,3,4-triazole derivatives. The HOMOe LUMO gap is affected by the substituents and linkage groups. Detonation performance is evaluated using the Kamlete Jacobs approach based on the calculated density and HOF. The results indicate that e NO2, e NF2, e NHe, e NHe NHe and e N]Ne groups are helpful for enhancing the detonation properties of di-1H-1,3,4-triazole derivatives. The bond dissociation energy and bond order of the weakest bonds are analyzed to investigate their stability. It is observed that the eC H2 e, e CH2 e CH2e and e CH]CHe groups are effective structural units for improving the stabilities of these derivatives. Considering the detonation performance and the stability, five compounds are screened as the potential candidates for high energy density materials.展开更多
文摘With the development of the social economy and the rise of the national fitness campaign, the development of sports functional beverage has become a part of sports consumption. Sports functional beverage has significant effect on improving athletic ability and fast recovery. But the inappropriate choice of beverage and drinking arrangements will cause irreparable damage to the body. Only the scientific and rational drinking, sports functional beverage will really play its whole function.
文摘Gold Medals in Summer Qlympics Measures A 1) Program to develop junior athletes to top level 2) National Training Center 3) National Coach Academy B 1) Sports medicine and sciences(JISS) 2) Anti-doping 3) To hold international
基金supported by the Major Projects of National Science and Technology(Grant No.2011ZX05040-005-002-001)the National Natural Science Foundation of China(Grant No.21276171 and 21276003)+1 种基金the National Younger Natural Science Foundation of China(Grant No.21103120)China Postdoctoral Science Foundation(Grant No.2012M520608)
文摘The formation mechanism of methane (CH4) during coal evolution has been investigated by density functional theory (DFT) of quantum chemistry. Thermogenic gas, which is generated during the thermal evolution of medium rank coal, is the main source of coalbed methane (CBM). Ethylbenzene (A) and 6,7-dimethyl-5,6,7,8-tetrahydro-1-hydroxynaphthalene (B) have been used as model compounds to study the pyrolysis mechanism of highly volatile bituminous coal (R), according to the similarity of bond orders and bond lengths. All possible paths are designed for each model. It can be concluded that the activation energies for H-assisted paths are lower than others in the process of methane formation; an H radical attacking on β-C to yield CH4 is the dominant path for the formation of CH4 from highly volatile bituminous coal. In addition, the calculated results also reveal that the positions on which H radical attacks and to which intramolecular H migrates have effects on methyl cleavage.
文摘In this paper we show that two significant phenomena of magnetospheric chorus emission can be explained by the participation of beam-like electron structures,created by Landau-resonant interaction with growing oblique whistler waves.The first concerns the widely observed spectral gap near half the electron cyclotron frequency Ωe;the second is related to the observation of very obliquely propagating lower-band waves that cannot be directly generated by temperature anisotropy.Concerning the gap,kinetic dispersion theory reveals that interference of the beam-related cyclotron mode ω~Ωe-kVb with the conventional whistler mode leads to mode splitting and the appearance of a ’forbidden’ area in the ω-k space.Thereby the beam velocity appears as an essential parameter.It is directly related to the phase velocity of the most unstable whistler wave mode,which is close to VAe/2 for sufficiently hot electrons(VAe is the electron Alfven velocity).To clarify the second point,we show that Landau-resonant beams with Vb Vb<VAe/2,which arise in cold plasmas from unstable upper-band waves,are able to generate lower-band whistler mode waves at very oblique propagation(θ≥60°).Our studies demonstrate the important role of Landau-resonant electrons in nonlinear whistler wave generation in the magnetosphere.
基金supported by the National Natural Science Foundation of China (Grant No.10974183)
文摘Oxygen vacancy formation and migration in La0.9Sr0.1Ga0.8Mg0.2O3-5 (LSGM) with various crystal symmetries (cubic, rhombohedral, orthorhombic, and monoclinic) are studied by employing first-principles calculations based on density functional theory (DFT). It is shown that the cubic LSGM has the smallest band gap, oxygen vacancy formation energy, and migration barrier, while the other three structures give rise to much larger values for these quantities, implying the best oxygen ion conductivity of the cubic LSGM among the four crystal structures. In out calculations, one oxygen vacancy migration pathway is considered in the cubic and rhombohedral structures due to all the oxygen sites being equivalent in them, while two vacancy migration pathways with different migration barriers are found in the orthorhombic and monoclinic symmetries owing to the existence of nonequivalent O1 and 02 oxygen sites. The migration energies along the migration pathway linking the two 02 sites are obviously lower than those along the pathway linking the O1 and 02 sites. Considering the phase transitions at high temperatures, the results obtained in this paper can not only explain the experimentally observed different behaviours of the oxygen ionic conductivity of LSGM with different symmetries, but also predict the rational crystal structures of LSGM for solid oxide fuel cell applications.
文摘The article presents the data of the assessment of the physical development and functional state of highly qualifiedgymnasts engaged in rhythmic gymnastics. It was found that high-skilled gymnasts have heterogeneity ofsomatotypes determined according to the B. Heath-J. Carter scheme and heterogeneity of types of autonomousnervous regulation of heart rate variability, systolic, diastolic blood pressure and respiration, determined on thespiroarteriorhythmocardiograph device. Highly qualified gymnasts have vago- and normotonic types of regulationof heart rate variability;normal-sympathetic-and hypersympathicotonic types of regulation of the variability ofsystolic blood pressure and diastolic blood pressure, vagotonic type of regulation of the variability of the respiratoryrhythm. Statistically significant differences gymnasts, successful in the medal standings at the internationalcompetitions and gymnasts participating, but not in high prizes in competitions, consist in the ability to resistfatigue while performing strenuous mental work (differences were revealed in 10-letter “Mental performance” at aconstant speed (p > 0.0001), and 3-letter test (p > 0.001)), data stabilometric test “Target” indicator “Time stabilityon the left foot” (R > 0.039) with the advantage of a high performing gymnasts artists. Fleshed out the possibility ofusing the parameters of the morphofunctional state of gymnasts in training for the qualitative evaluation of thephysical development of gymnasts, evaluation set their sports uniforms indicated the possibility of developing thereference parameters of the morphofunctional status of gymnasts and recommendations on the frequency of thesurvey of morphological and functional status of gymnasts involved in rhythmic gymnastics.
文摘With the widespread development of international sports events, more and more people pay attention to the international sports games by reading sports news or watching sports videos. Since English is the universal language, the news of these sports events is mostly reported in English. However,English sports news could bring some reading difficulties for Chinese readers. In the author's view, words are the basic elements of the English sports news language. It is of significance to study English sports news lexis. Under the guidance of Functional Equivalence Theory,this study attempts to explore the lexical features of English sports news and to analyze some useful lexical translation strategies. The results of the study show that Nida's Functional Equivalence Theory is applicable to the lexical translation of English sports news. It is recommended that translators follow Nida's equivalence theory during the translation.
基金the National Natural Science Foundation of China(51576064,51776070)Beijing Nova Program(Z171100001117064)+2 种基金Beijing Natural Science Foundation(3172030)grants from the Fok Ying Tung Education Foundation(161051)Fundamental Research Funds for the Central Universities(2018QN057,2018ZD08)for financial support。
文摘The catalytic fast pyrolysis of cellulose impregnated with phosphoric acid (H3PO4) offers a promising method for the selective production of levoglucosenone (LGO),a valuable anhydrosugar product.However,the fundamental mechanism for selective LGO formation is unclear.Herein,quantum chemistry calculations and catalytic fast pyrolysis experiments were performed to reveal the formation mechanism of LGO in H3PO4-catalyzed cellulose pyrolysis.H3PO4 significantly decreased the energy barriers of the pyrolytic reactions and altered the competitiveness of the LGO formation pathways,promoting LGO formation.Through different pathways in the non-catalytic and H3P04-catalyzed conditions,LGO is mainly produced from the primary decomposition of glucose units of cellulose and secondary conversion of levoglucosan.The major catalytic formation pathways of LGO comprise similar reactions,with dehydration at the 3-OH+2-H site as the rate-determining step.Importantly,secondary conversion of 1,4;3,6-dianhydro-α-D-glucopyranose is not feasible for LGO formation,in contrast to previous reports.In addition,a high degree of polymerization is beneficial for the selectivity of LGO formation in the catalytic process,because the glycosidic bond is important for the formation of the bicyclic structure (1,5-and1,6-acetal rings).
基金Project supported by the National Natural Science Foundation of China (Grant No.11074135)
文摘An effective structural codoping approach is proposed to modify the photoelectrochemical (PEC) properties of anatase TiO2 by being doped with nonmetal (N or/and C) and transition metal (Re) elements. The electronic structures and for- mation energies of different doped systems are investigated using spin-polarized density functional theory. We find that (C, Re) doped TiO2, with a low formation energy and a large binding energy, reduces the band gap to a large extent, thus it could contribute to the significant enhancement of the photocatalytic activity in the visible-light region. It should be pointed out that, to be successful, the proper proportion of the dopants C and Re should be controlled, so that reasonable PEC properties can be achieved.
基金supported by the Science and Technology Foundation of China Academy of Engineering Physics(Grant No 20050212)
文摘Based on density functional theory, using the scheme of the linearized augmented plane wave and the improved local orbital (APW+lo), this paper analyses and calculates the lattice parameters, formation energy and magnetism of the rare-earth permanent magnetic materials YFe12-xCrx (x = 0 - 5). The stabilization effect and the possible positions of the substituted atom Cr are analysed. Magnetic moments for the system and the atoms are obtained.
文摘The theoretical calculation of LaNi4Co, in which Co substituted for Ni at various sites, was performed by adopting the method of total energy based on the Density Functional Theory. The augmented plane wave function was selected as a basis set in combination with Ultra-soft Pseudopotential technology. The geometry of LaNi5 was optimized and the parameters and properties of the structure were given. The theoretical results accord well with experiments. This method provides a theoretical approach for the structure prediction of such alloy. The calculations of total energy, electronic density of states and Mulliken population of LaNi4Co were carried out. The electronic structure of LaNi4Co and the change of the electronic structure due to the Co-substitution in LaNi5 alloy were analyzed from the calculated results. The stability of the alloy in which Ni was partially substituted by Co at various sites was compared and the factors controlling stability were discussed. The theoretical value of formation heat was calculated.
文摘In this paper, the thermodynamic parameters are calculated for all gaseous Poly Chlorinat Dibenzo-p-dioxins (PCDDs) using the Density Functional Theory (DFF) method and both the enthalpy of formation (ΔfH^0) and Gibbs free energy of formation (Δf G^0) are derived, from which the order of stability of individual congeners is then predicted. All these properties, together with the calculated entropies ( S^0) and heat capacities ( Cp), are presented as a function of the number of chlorine atoms in the various PCDD molecules. The accuracy of the method used here, is evaluated by comparing the thermodynamic parameters of gaseous chlorobenzenes with experimental values collected from literature.
文摘Reservoir connectivity is a critical issue in the process of oil-gas exploration and development. According to the theory of fluid mechanics and the achievements of many scholars, a connected reservoir coincides with a unified formation pressure system;there is a linear relationship between formation pressure and depth in normal pressure system reservoir. However, in high-permeability or multi-phase fluid reservoirs, this method has poor applicability and limitations. Through theoretical analysis and formula derivation, a new method for judging the connectivity of normal pressure reservoirs is found, that is, the inverse proportional function relationship between the pressure coefficient and the depth. In this paper, the relationship between the pressure system and the inverse proportional function has been verified. The function of the same pressure system is unique, monotonic, and has unified asymptote and symmetry axis and vice versa. Examples show that the inverse proportional function is more accurate and reliable for judging reservoir connectivity than the linear function.
基金the Singapore Ministry of Education(T1-2015 Apr-03)the National University of SingaporeInstitute for Health Innovation and Technology to JJEC.
文摘The human brain contains an estimated 100 billion neurons that must be systematically organized into functional neural circuits for it to function properly.These circuits range from short-range local signaling networks between neighboring neurons to long-range networks formed between various brain regions.Compelling converging evidence indicates that alterations in neural circuits arising from abnormalities during early neuronal development or neurodegeneration contribute significantly to the etiology of neurological disorders.Supporting this notion,efforts to identify genetic causes of these disorders have uncovered an over-representation of genes encoding proteins involved in the processes of neuronal differentiation,maturation,synaptogenesis and synaptic function.Fasciculation and elongation protein zeta-1,a Kinesin-1 adapter,has emerged as a key central player involved in many of these processes.Fasciculation and elongation protein zeta-1-dependent transport of synaptic cargoes and mitochondria is essential for neuronal development and synapse establishment.Furthermore,it acts downstream of guidance cue pathways to regulate axo-dendritic development.Significantly,perturbing its function causes abnormalities in neuronal development and synapse formation both in the brain as well as the peripheral nervous system.Mutations and deletions of the fasciculation and elongation protein zeta-1 gene are linked to neurodevelopmental disorders.Moreover,altered phosphorylation of the protein contributes to neurodegenerative disorders.Together,these findings strongly implicate the importance of fasciculation and elongation protein zeta-1 in the establishment of neuronal circuits and its maintenance.
基金the National Natural Science Foundation of China.
文摘Using Chandra ACIS S3 data we studied the X-ray properties of low-and highmass X-ray binary populations in the nearby spiral galaxy NGC 5055. A total of 43 X-ray point sources were detected within two effective radii, with 31 sources located on the disk and the rest 12 sources in the bulge. The resolved point sources dominate the X-ray emission of the galaxy, accounting for about 80% of the total counts in 0.3-10keV. From spectral fittings we calculated the 0.3-10.0keV luminosities of all the detected X-ray point sources and found that they span a wide range from a few times 10^37 erg s^-1 to over 10^39 erg s^-1. After compensating for incompleteness at the low luminosity end, we found that the corrected XLF of the bulge population is well fitted with a broken power-law with a break at 1.57-0.20^+0.21 1038 erg s^-1, while the profile of the disk population's XLF agrees with a single powerlaw distribution of slope 0 9-0.06^+0.07 The disk population is significantly richer at ≥ 2 × 10^38 erg s^- 1 than the bulge population, indicating that the disk may have undergone relatively recent, strong starbursts that significantly increased the HMXB population, although ongoing starbursts are also observed in the nuclear region. Similar XLF profiles of the bulge and disk populations were found in M81. However, in most other spiral galaxies different patterns of spatial variation of the XLF profiles from the bulge to the disk have been observed, indicating that the star formation and evolution history may be more complex than we have expected.
文摘For the case where the multivariate normal population does not have null correlations, we give the exact expression of the distribution of the sample matrix of correlations R, with the sample variances acting as parameters. Also, the distribution of its determinant is established in terms of Meijer G-functions in the null-correlation case. Several numerical examples are given, and applications to the concept of system de- pendence in Reliability Theory are presented.
文摘In this paper, the strain energy function proposed by Shang and Cheng was generalized by introducing a nonlinear term. Void formation and growth in the interior of a sphere composed of compressible hyper-elastic material, subjected to a prescribed uniform displacement, was examined. A parametric cavitated bifurcation solution for the radial deformed function was obtained. Stability of the solution of the cavitated bifurcation equation was discussed. With the appearance of a cavity, an interesting feature of the radial deformation near the deformed cavity wall is the transition from extension to compression.
基金Projects(50436010 50375055) supported by the National Natural Science Foundation of China+1 种基金 Project(04105942) supported by the Natural Science Foundation of Guangdong Province, China Project(2005B10201002) supported by Scientific and Technological Project of Guangdong Province, China
文摘An extrusion-ploughing process was presented to fabricate the integral fin function-surface. Cutting edge inclination angle and rake angle can be calculated from the tool’s geometry relationship. The description of fins’ geometry characters was standardized. The experiments show that, when the middle cutting edge’s inclination angle η is less than 35°, continuous fin will come out; when η is between 35° and 55°, the fins will be saw-tooth ones, and the fins will be torn when this angle is above 55°; when the extrusion angle θ is between 60° and 150°, the fins will appear, or else, the fins will be torn into chips from the base. Forming angle and clearance angle have little effect on fin’s formation. For continuous fin, its height is close to cutting depth when it is small, but it will become approximately constant as cutting depth grows; for saw-tooth fins, the width, the height, as well as the clearance will increase with the increase of cutting depth, but the increment of clearance is small; neither for continuous fin, nor for saw-tooth ones, cutting velocity has little influence on their structure parameters.
基金2022 project of the Training and Research Center for Ideological and Political Workers in Colleges and Universities of the Ministry of Education(Southwest Jiaotong University)titled"Research on the Sociocultural and Psychological Mechanism of Casting the Consciousness of the Chinese Nation Community",No.SWJTUKF22-06.
文摘BACKGROUND In high-intensity sports like golf,knee joints are prone to injury,leading to pain,limited mobility,and decreased quality of life.Traditional treatment methods typically involve rehabilitation exercises,but their effectiveness may be limited.In recent years,sodium hyaluronate has emerged as a widely used biomedical material in the treatment of joint diseases.AIM To explore the effect of sodium hyaluronate combined with rehabilitation training on pain degree,flexion range of motion and motor function of knee joint injured by golf.METHODS Eighty patients with knee joint injury caused by golf were randomly divided into control(group B)and observation group(group A).The group B was treated with rehabilitation training,and the group A was treated with sodium hyaluronate combined with rehabilitation training.The clinical efficacy,range of motion and function of knee joint,quality of life and inflammatory factors were compared.RESULTS The excellent and good rate of rehabilitation in the group A was raised than group B.At 6 weeks and 3 months after treatment,the range of motion of the two groups was raised than that before treatment,and that of the group A was raised than group B.After treatment,the scores of Lysholm and International Knee Documentation Committee(IKDC)in the group A were raised,and those in the group A were raised than group B.The VAS score of the two groups was reduced than that of the group B,and the SF-36 score of the group A was reduced than group B.The interleukin(IL)-1β,IL-8 and tumor necrosis factor-αin the two groups were reduced,and those in the group A were reduced than group B.CONCLUSION Sodium hyaluronate combined with rehabilitation training has a good clinical effect in the treatment of patients with knee joint injury caused by golf,which relieve pain,maintain knee joint function and improve patients'life quality.
文摘Computations by density functional theory(DFT) method are performed on a series of di-1H-1,3,4-triazole derivatives with different substituents and linkages. The heat of formation(HOF) is predicted by the designed isodesmic reactions. The predicted results reveal that eN 3and eN ]Ne groups are effective structural units for increasing the HOF values of the di-1H-1,3,4-triazole derivatives. The HOMOe LUMO gap is affected by the substituents and linkage groups. Detonation performance is evaluated using the Kamlete Jacobs approach based on the calculated density and HOF. The results indicate that e NO2, e NF2, e NHe, e NHe NHe and e N]Ne groups are helpful for enhancing the detonation properties of di-1H-1,3,4-triazole derivatives. The bond dissociation energy and bond order of the weakest bonds are analyzed to investigate their stability. It is observed that the eC H2 e, e CH2 e CH2e and e CH]CHe groups are effective structural units for improving the stabilities of these derivatives. Considering the detonation performance and the stability, five compounds are screened as the potential candidates for high energy density materials.