目的调查并分析北京市某高校男性运动人群春季饮水量、排尿量与水合状态,为后期开展针对性的饮水宣教提供科学依据。方法采用简单随机抽样方法抽取北京市某高校男性运动人群109名,采用连续7 d 24 h饮水记录法调查其饮水量,采用双份饭法...目的调查并分析北京市某高校男性运动人群春季饮水量、排尿量与水合状态,为后期开展针对性的饮水宣教提供科学依据。方法采用简单随机抽样方法抽取北京市某高校男性运动人群109名,采用连续7 d 24 h饮水记录法调查其饮水量,采用双份饭法与称重法,对研究对象食用的食物进行称重采样送检,调查其食物水摄入量,收集调查对象连续3 d的尿液,记录其排尿量并进行检测,使用训练计划估算其每周运动训练的能量消耗。结果调查对象整体每日饮水量的中位数为1 789 m L,每日食物水摄入量的中位数为955 m L,每日总水摄入量的中位数为2 701 m L,每日24 h排尿量的中位数为850 m L,15.6%的研究对象处于适宜水合状态,43.1%处于脱水状态。不同体脂率(BF%)、体质量指数(BMI)等级的研究对象每日饮水量、食物水摄入量、总水摄入量与排尿量差异均无统计学意义(P值均>0.05)。不同运动训练能量消耗等级的研究对象每日饮水量、总水摄入量差异均有统计学意义(χ^2值分别为9.20,8.43,P值均<0.05)。结论相比普通人群,北京市某高校男性运动人群的每日饮水量与总水摄入量较高,排尿量较低,且存在水合状态较差的现象,应对其进行针对性的饮水宣教。展开更多
Investigating the impact of microhydration on the excited-states and electronic excitation properties of biomolecules has remained one of the important yet challenging aspects of science because of the complexity of d...Investigating the impact of microhydration on the excited-states and electronic excitation properties of biomolecules has remained one of the important yet challenging aspects of science because of the complexity of developing models. However, with the advent of computational chemistry methods such as TD-DFT, many useful insights about the electronic excitation energy and excited-state nature of biomolecules can be explored. Accordingly, in our study, we have incorporated the TD-DFT/wB97XD/cc-pVTZ method to study the excited state properties of N-acetyl phenylalanine amide (NAPA-A(H<sub>2</sub>O) <sub>n</sub>) (n = 1 to 4) clusters from ground to the tenth lowest gaseous singlet excited state. We found that the C=O bond length gradually increases both in N-terminal amide and C-terminal amide after the sequential addition of water molecules because of intermolecular H-bonding and this intermolecular H-bonding becomes weaker after the sequential addition of H<sub>2</sub>O molecules. The UV absorption maxima of NAPA-A (H<sub>2</sub>O)<sub>n</sub> (n = 1 - 4) clusters consisted of two peaks that are S<sub>5</sub>←S<sub>0</sub> (1<sup>st</sup> absorption) and S<sub>6</sub>←S<sub>0</sub> (2<sup>nd</sup> absorption) excitations. The first absorption maxima were blue-shifted with the increase in oscillator strength. This means that strong H-bonds reduce the charge transfer and make clusters more rigid. On the other hand, the second absorption maxima were red-shifted with the decrease in oscillator strength. In the ECD spectra, the negative bands indicate the presence of an amide bond and L-configuration of micro hydrated NAPA-A clusters. Finally, our calculated absorption and fluorescence energy confirm that all the NAPA-A (H<sub>2</sub>O) <sub>n</sub> (n = 0 - 4) clusters revert to the ground state from the fluorescent state by emitting around 5.490 eV of light.展开更多
文摘目的调查并分析北京市某高校男性运动人群春季饮水量、排尿量与水合状态,为后期开展针对性的饮水宣教提供科学依据。方法采用简单随机抽样方法抽取北京市某高校男性运动人群109名,采用连续7 d 24 h饮水记录法调查其饮水量,采用双份饭法与称重法,对研究对象食用的食物进行称重采样送检,调查其食物水摄入量,收集调查对象连续3 d的尿液,记录其排尿量并进行检测,使用训练计划估算其每周运动训练的能量消耗。结果调查对象整体每日饮水量的中位数为1 789 m L,每日食物水摄入量的中位数为955 m L,每日总水摄入量的中位数为2 701 m L,每日24 h排尿量的中位数为850 m L,15.6%的研究对象处于适宜水合状态,43.1%处于脱水状态。不同体脂率(BF%)、体质量指数(BMI)等级的研究对象每日饮水量、食物水摄入量、总水摄入量与排尿量差异均无统计学意义(P值均>0.05)。不同运动训练能量消耗等级的研究对象每日饮水量、总水摄入量差异均有统计学意义(χ^2值分别为9.20,8.43,P值均<0.05)。结论相比普通人群,北京市某高校男性运动人群的每日饮水量与总水摄入量较高,排尿量较低,且存在水合状态较差的现象,应对其进行针对性的饮水宣教。
文摘Investigating the impact of microhydration on the excited-states and electronic excitation properties of biomolecules has remained one of the important yet challenging aspects of science because of the complexity of developing models. However, with the advent of computational chemistry methods such as TD-DFT, many useful insights about the electronic excitation energy and excited-state nature of biomolecules can be explored. Accordingly, in our study, we have incorporated the TD-DFT/wB97XD/cc-pVTZ method to study the excited state properties of N-acetyl phenylalanine amide (NAPA-A(H<sub>2</sub>O) <sub>n</sub>) (n = 1 to 4) clusters from ground to the tenth lowest gaseous singlet excited state. We found that the C=O bond length gradually increases both in N-terminal amide and C-terminal amide after the sequential addition of water molecules because of intermolecular H-bonding and this intermolecular H-bonding becomes weaker after the sequential addition of H<sub>2</sub>O molecules. The UV absorption maxima of NAPA-A (H<sub>2</sub>O)<sub>n</sub> (n = 1 - 4) clusters consisted of two peaks that are S<sub>5</sub>←S<sub>0</sub> (1<sup>st</sup> absorption) and S<sub>6</sub>←S<sub>0</sub> (2<sup>nd</sup> absorption) excitations. The first absorption maxima were blue-shifted with the increase in oscillator strength. This means that strong H-bonds reduce the charge transfer and make clusters more rigid. On the other hand, the second absorption maxima were red-shifted with the decrease in oscillator strength. In the ECD spectra, the negative bands indicate the presence of an amide bond and L-configuration of micro hydrated NAPA-A clusters. Finally, our calculated absorption and fluorescence energy confirm that all the NAPA-A (H<sub>2</sub>O) <sub>n</sub> (n = 0 - 4) clusters revert to the ground state from the fluorescent state by emitting around 5.490 eV of light.
