We derived an equation for saturation in carbonate reservoirs based on the electrical efficiency model in the case of lacking core data. Owing to the complex pore structure and strong heterogeneity in carbonate reserv...We derived an equation for saturation in carbonate reservoirs based on the electrical efficiency model in the case of lacking core data. Owing to the complex pore structure and strong heterogeneity in carbonate reservoirs, the relation between electrical efficiency and water porosity is either complex or linear. We proposed an electrical efficiency equation that accounts for the relation between electrical efficiency and water porosity. We also proposed a power-law relation between electrical efficiency and deep-formation resistivity and analyzed the factors controlling the error in the water saturation computations. We concluded that the calculation accuracy of the electrical efficiency is critical to the application of the saturation equation. The saturation equation was applied to the carbonate reservoirs of three wells in Iraq and Indonesia. For relative rock electrical efficiency error below 0.1, the water saturation absolute error is also below 0.1. Therefore, we infer that the proposed saturation equation generally satisfies the evaluation criteria for carbonate reservoirs.展开更多
The spatial characteristics of residents’ leisure activities not only reflect their demand for urban leisure space but also affect the urban spatial layout. This study takes Shenyang, China as an example and analyzes...The spatial characteristics of residents’ leisure activities not only reflect their demand for urban leisure space but also affect the urban spatial layout. This study takes Shenyang, China as an example and analyzes the characteristics of residents’ leisure activities through questionnaires. On this basis, it uses point of interest data and mobile phone signaling data to identify various types of residential and leisure functional relationships, and uses spatial analysis and community detection to assess the distance characteristics, flow patterns, and community structure of residents’ leisure activities, so as to discuss the spatial structure of residents’ leisure activities in Shenyang. The results showed that: (1) in addition to leisure at home, Shenyang residents mainly went to shopping malls, supermarkets,and parks for leisure activities, and the proportions of residents of the two types of leisure activities were approximately equal;(2) the average distances that residents traveled for shopping and park leisure were near in the middle and far in the periphery, and the travel costs of peripheral residents for centrally located leisure were higher than those for residents in central areas;(3) the flow patterns of the residential-shopping and residential-park functional relationships displayed clustering mode characteristics, and Shenyang presented a significant monocentric structure;and (4) residents’ shopping activities were concentrated in the southern community, and walking in the park activities were concentrated in the western community. Residents’ leisure activities were characterized by centripetal agglomeration,which was prone to problems such as traffic congestion and big city diseases. The spatial expansion process in the city was characterized by obvious directional inheritance and path dependence, and the construction of sub-cities is needed to improve the related service facilities.展开更多
AIM:To determine the Bruch's membrane opening-minimum rim width(BMO-MRW) tipping point where corresponding visual field(VF) damages become detectable.METHODS:A total of 85 normal subjects and 83 glaucoma patie...AIM:To determine the Bruch's membrane opening-minimum rim width(BMO-MRW) tipping point where corresponding visual field(VF) damages become detectable.METHODS:A total of 85 normal subjects and 83 glaucoma patients(one eye per participant) were recruited for the study.All of the patients had VF examinations and spectral-domain optical coherence tomography to measure the BMO-MRW.Total deviation values for 52 VF points were allocated to the corresponding sector according to the Garway-Heath distribution map.To evaluate the relationship between VF loss and BMOMRW measurements,a "broken-stick" statistical model was used.The tipping point where the VF values started to sharply decrease as a function of BMO-MRW measurements was estimated and the slopes above and below this tipping point were compared.RESULTS:A 25.9% global BMO-MRW loss from normative value was required for the VF loss to be detectable.Sectorally,substantial BMO-MRW thinning in inferotemporal sector(33.1%) and relatively less BMO-MRW thinning in the superotemporal sector(8.9%) were necessary for the detection of the VF loss.Beyond the tipping point,the slopes were close to zero throughout all of the sectors and the VF loss was unrelated to the BMO-MRW loss.The VF loss was related to the BMO-MRW loss below the tipping point.The difference between the two slopes was statistically significant(P≤0.002).CONCLUSION:Substantial BMO-MRW loss appears to be necessary for VF loss to be detectable in patients with open angle glaucoma with standard achromatic perimetry.展开更多
To alleviate the global warming by removing excess CO_(2) and converting them into value-added chemicals,(photo)electrochemical reduction has been recognized as a promising strategy.As the CO_(2) reduction reaction(CO...To alleviate the global warming by removing excess CO_(2) and converting them into value-added chemicals,(photo)electrochemical reduction has been recognized as a promising strategy.As the CO_(2) reduction reaction(CO_(2) RR) is involved with multiple electrons and multiple products,plus the complexity of the surface chemical environment of the catalyst,it is extremely challenging to establish the structure/function relationship.Atomically precise metal nanoclusters(NCs),with crystallographically resolved structure,molecule-like characters and strong quantum confinement effects,have been emerging as a new type of catalyst for CO_(2) RR,and more importantly,they can provide an ideal platform to unravel the comprehensive mechanistic insights and establish the structure/function relationship eventually.In this review,the recent advances regarding employing molecular metal NCs with well-defined structure including Au NCs,Au-based alloy NCs,Ag NCs,Cu NCs for CO_(2) RR and relevant mechanistic studies are discussed,and the opportunities and challenges are proposed at the end for paving the development of CO_(2) RR by using atomically precise metal NCs.展开更多
This paper defines a new kind of rule, probability functional dependency rule. The functional dependency degree can be depicted by this kind of rule. Five algorithms, from the simple to the complex, are presefited to ...This paper defines a new kind of rule, probability functional dependency rule. The functional dependency degree can be depicted by this kind of rule. Five algorithms, from the simple to the complex, are presefited to mine this kind of rule in different condition. The related theorems are proved to ensure the high efficiency and the correctness of the above algorithms.展开更多
Platelet plays an importent role in thromboembolic diseases. It is demonstrated that recurrent pulmonary embolism may cause pulmonary hypertention. In recent years,P-selectin(granule membrane protein,GMP40)was fou...Platelet plays an importent role in thromboembolic diseases. It is demonstrated that recurrent pulmonary embolism may cause pulmonary hypertention. In recent years,P-selectin(granule membrane protein,GMP40)was found to be a surface marker for platelet activation.展开更多
DFT/B3LYP/6-311G+(d,p) basis set including solvent effect was first used to calculate a set of molecular descriptors of 55 phenylalkylamine and 20 tryptamine compounds with hallucinogenic activity. Four quantitativ...DFT/B3LYP/6-311G+(d,p) basis set including solvent effect was first used to calculate a set of molecular descriptors of 55 phenylalkylamine and 20 tryptamine compounds with hallucinogenic activity. Four quantitative structure-activity relationship (QSAR) models of the hallucinogenic activity for phenylalkylamines and tryptamines were obtained by employing multiple linear regression (MLR) method. The QSAR analysis indicated that electron-related descriptors were major contributors to the hallucinogenic activities of phenylalkylamines and tryp- tamines. In addition, electron-unrelated descriptors have some impact on the hallucinogenic activities of phenylal- kylamines. Based on the results of QSAR study, a novel Conformation Complementary Judgement, Transformation and Induction (CCJTI) model had been proposed to explain different action mechanisms of phenylalkylamines and tryptamines with their target receptors. It was concluded that phenylalkylamines might combine with receptor by electronic effect, but steric factor could affect it also, whereas tryptamines could act only through the electronic effect.展开更多
Objective: To investigate the involvement of pulmonary function impairment in ulcerative colitis(UC), and explore a scientific basis for the Chinese medicine(CM) theory of exterior-interior correlation between L...Objective: To investigate the involvement of pulmonary function impairment in ulcerative colitis(UC), and explore a scientific basis for the Chinese medicine(CM) theory of exterior-interior correlation between Lung(Fei) and Large intestine(Dachang). Methods: Totally 120 patients with a diagnosis of UC were recruited and the demographics, clinical data, and blood samples were collected. C-reactive protein(CRP) and erythrocyte sedimentation rate(ESR) concentrations were measured. Every patient accepted pulmonary function test and took chest radiograph(CXR). Results: Pulmonary function abnormalities were present in 72 of 120 patients. The median(interquartile range) vital capacity(VC), forced vital capacity(FVC), forced expiratory volume in 1 s(FEV_1), carbon monoxide diffusion capacity(DL_∞) of lung, total lung capacity(TLC) and functional residual volume(FRV) were decreased in distal UC and pancolitis compared with ulcerative prochitis(P〈0.0005). Male patients had increased VC, FEV_1/FVC, and residual volume(RV)/TLC compared with female(P〈0.0005), but decreased DLCO and carbon monoxide iffusion capacity(KCO) of lung/alveolar ventilation(P〈0.0005). Age was strongly correlated with RV(Spearman rank correlation coefficient(rs)=–0.57, P〈0.0001), and RV/TLC(rs=0.48, P〈0.0001). Age was also correlated with FEV_1/FVC(rs=–0.29, P=0.001), forced expiratory flow in 75% vital capacity(FEF75%, rs=–0.20, P=0.03), DLCO(rs=–0.21, P=0.02), TLC(rs=–0.25, P=0.006), and FRV(rs=–0.28, P=0.002). The course of disease was correlated with FEF75%(rs=–0.18, P=0.049) and KCO(rs=–0.19, P=0.036). Chest radiograph abnormalities were presented in 38 of 120. Pulmonary symptoms were presented in 10 of 120. Other extraintestinal complications were presented in 21 of 120. Conclusions: Pulmonary function impairment was more frequently than other extraintestinal complications in UC patients, which may be affected by sex, age, extent and course of disease. These results may be a scientific basis for the theory of exterior-interior correlation between Lung and Large intestine.展开更多
The mutation sites of the four mutants F35Y, P40V, V45E and V45Y of cytochrome b 5 are located at the edge of the heme binding pocket. The solvent accessible areas of the “pocket interior” of the four mutants ...The mutation sites of the four mutants F35Y, P40V, V45E and V45Y of cytochrome b 5 are located at the edge of the heme binding pocket. The solvent accessible areas of the “pocket interior” of the four mutants and the wild type cytochrome b 5 have been calculated based on their crystal structures at high resolution. The change in the hydrophobicity of the heme binding pocket resulting from the mutation can be quantitatively described using the difference of the solvent accessible area of the “pocket interior” of each mutant from that of the wild type cytochrome b 5. The influences of the hydrophobicity of the heme binding pocket on the protein stability and redox potential are discussed.展开更多
基金supported by the National Science and Technology Major Project(2011ZX05030)
文摘We derived an equation for saturation in carbonate reservoirs based on the electrical efficiency model in the case of lacking core data. Owing to the complex pore structure and strong heterogeneity in carbonate reservoirs, the relation between electrical efficiency and water porosity is either complex or linear. We proposed an electrical efficiency equation that accounts for the relation between electrical efficiency and water porosity. We also proposed a power-law relation between electrical efficiency and deep-formation resistivity and analyzed the factors controlling the error in the water saturation computations. We concluded that the calculation accuracy of the electrical efficiency is critical to the application of the saturation equation. The saturation equation was applied to the carbonate reservoirs of three wells in Iraq and Indonesia. For relative rock electrical efficiency error below 0.1, the water saturation absolute error is also below 0.1. Therefore, we infer that the proposed saturation equation generally satisfies the evaluation criteria for carbonate reservoirs.
基金Under the auspices of National Natural Science Foundation of China(No.41871162)。
文摘The spatial characteristics of residents’ leisure activities not only reflect their demand for urban leisure space but also affect the urban spatial layout. This study takes Shenyang, China as an example and analyzes the characteristics of residents’ leisure activities through questionnaires. On this basis, it uses point of interest data and mobile phone signaling data to identify various types of residential and leisure functional relationships, and uses spatial analysis and community detection to assess the distance characteristics, flow patterns, and community structure of residents’ leisure activities, so as to discuss the spatial structure of residents’ leisure activities in Shenyang. The results showed that: (1) in addition to leisure at home, Shenyang residents mainly went to shopping malls, supermarkets,and parks for leisure activities, and the proportions of residents of the two types of leisure activities were approximately equal;(2) the average distances that residents traveled for shopping and park leisure were near in the middle and far in the periphery, and the travel costs of peripheral residents for centrally located leisure were higher than those for residents in central areas;(3) the flow patterns of the residential-shopping and residential-park functional relationships displayed clustering mode characteristics, and Shenyang presented a significant monocentric structure;and (4) residents’ shopping activities were concentrated in the southern community, and walking in the park activities were concentrated in the western community. Residents’ leisure activities were characterized by centripetal agglomeration,which was prone to problems such as traffic congestion and big city diseases. The spatial expansion process in the city was characterized by obvious directional inheritance and path dependence, and the construction of sub-cities is needed to improve the related service facilities.
文摘AIM:To determine the Bruch's membrane opening-minimum rim width(BMO-MRW) tipping point where corresponding visual field(VF) damages become detectable.METHODS:A total of 85 normal subjects and 83 glaucoma patients(one eye per participant) were recruited for the study.All of the patients had VF examinations and spectral-domain optical coherence tomography to measure the BMO-MRW.Total deviation values for 52 VF points were allocated to the corresponding sector according to the Garway-Heath distribution map.To evaluate the relationship between VF loss and BMOMRW measurements,a "broken-stick" statistical model was used.The tipping point where the VF values started to sharply decrease as a function of BMO-MRW measurements was estimated and the slopes above and below this tipping point were compared.RESULTS:A 25.9% global BMO-MRW loss from normative value was required for the VF loss to be detectable.Sectorally,substantial BMO-MRW thinning in inferotemporal sector(33.1%) and relatively less BMO-MRW thinning in the superotemporal sector(8.9%) were necessary for the detection of the VF loss.Beyond the tipping point,the slopes were close to zero throughout all of the sectors and the VF loss was unrelated to the BMO-MRW loss.The VF loss was related to the BMO-MRW loss below the tipping point.The difference between the two slopes was statistically significant(P≤0.002).CONCLUSION:Substantial BMO-MRW loss appears to be necessary for VF loss to be detectable in patients with open angle glaucoma with standard achromatic perimetry.
基金the grant from the National Natural Science Foundation of China(No.21805170)financial support from Guangdong Natural Science Funds for Distinguished Young Scholars(No.2015A030306006)+1 种基金Guangzhou Science and Technology Plan Projects(No.201804010323)the fundamental funds for central universities(SCUT No.2018ZD022)。
文摘To alleviate the global warming by removing excess CO_(2) and converting them into value-added chemicals,(photo)electrochemical reduction has been recognized as a promising strategy.As the CO_(2) reduction reaction(CO_(2) RR) is involved with multiple electrons and multiple products,plus the complexity of the surface chemical environment of the catalyst,it is extremely challenging to establish the structure/function relationship.Atomically precise metal nanoclusters(NCs),with crystallographically resolved structure,molecule-like characters and strong quantum confinement effects,have been emerging as a new type of catalyst for CO_(2) RR,and more importantly,they can provide an ideal platform to unravel the comprehensive mechanistic insights and establish the structure/function relationship eventually.In this review,the recent advances regarding employing molecular metal NCs with well-defined structure including Au NCs,Au-based alloy NCs,Ag NCs,Cu NCs for CO_(2) RR and relevant mechanistic studies are discussed,and the opportunities and challenges are proposed at the end for paving the development of CO_(2) RR by using atomically precise metal NCs.
文摘This paper defines a new kind of rule, probability functional dependency rule. The functional dependency degree can be depicted by this kind of rule. Five algorithms, from the simple to the complex, are presefited to mine this kind of rule in different condition. The related theorems are proved to ensure the high efficiency and the correctness of the above algorithms.
文摘Platelet plays an importent role in thromboembolic diseases. It is demonstrated that recurrent pulmonary embolism may cause pulmonary hypertention. In recent years,P-selectin(granule membrane protein,GMP40)was found to be a surface marker for platelet activation.
基金Project supported by the Natural Science Foundation of Shanxi Province (No. 2007011025) and Scientific Research Foundation for the Returned Overseas Chinese Scholars of Shanxi Province.
文摘DFT/B3LYP/6-311G+(d,p) basis set including solvent effect was first used to calculate a set of molecular descriptors of 55 phenylalkylamine and 20 tryptamine compounds with hallucinogenic activity. Four quantitative structure-activity relationship (QSAR) models of the hallucinogenic activity for phenylalkylamines and tryptamines were obtained by employing multiple linear regression (MLR) method. The QSAR analysis indicated that electron-related descriptors were major contributors to the hallucinogenic activities of phenylalkylamines and tryp- tamines. In addition, electron-unrelated descriptors have some impact on the hallucinogenic activities of phenylal- kylamines. Based on the results of QSAR study, a novel Conformation Complementary Judgement, Transformation and Induction (CCJTI) model had been proposed to explain different action mechanisms of phenylalkylamines and tryptamines with their target receptors. It was concluded that phenylalkylamines might combine with receptor by electronic effect, but steric factor could affect it also, whereas tryptamines could act only through the electronic effect.
基金Supported by the National Basic Research Program,Ministry of Science and Technology,China(No.2009CB522705)
文摘Objective: To investigate the involvement of pulmonary function impairment in ulcerative colitis(UC), and explore a scientific basis for the Chinese medicine(CM) theory of exterior-interior correlation between Lung(Fei) and Large intestine(Dachang). Methods: Totally 120 patients with a diagnosis of UC were recruited and the demographics, clinical data, and blood samples were collected. C-reactive protein(CRP) and erythrocyte sedimentation rate(ESR) concentrations were measured. Every patient accepted pulmonary function test and took chest radiograph(CXR). Results: Pulmonary function abnormalities were present in 72 of 120 patients. The median(interquartile range) vital capacity(VC), forced vital capacity(FVC), forced expiratory volume in 1 s(FEV_1), carbon monoxide diffusion capacity(DL_∞) of lung, total lung capacity(TLC) and functional residual volume(FRV) were decreased in distal UC and pancolitis compared with ulcerative prochitis(P〈0.0005). Male patients had increased VC, FEV_1/FVC, and residual volume(RV)/TLC compared with female(P〈0.0005), but decreased DLCO and carbon monoxide iffusion capacity(KCO) of lung/alveolar ventilation(P〈0.0005). Age was strongly correlated with RV(Spearman rank correlation coefficient(rs)=–0.57, P〈0.0001), and RV/TLC(rs=0.48, P〈0.0001). Age was also correlated with FEV_1/FVC(rs=–0.29, P=0.001), forced expiratory flow in 75% vital capacity(FEF75%, rs=–0.20, P=0.03), DLCO(rs=–0.21, P=0.02), TLC(rs=–0.25, P=0.006), and FRV(rs=–0.28, P=0.002). The course of disease was correlated with FEF75%(rs=–0.18, P=0.049) and KCO(rs=–0.19, P=0.036). Chest radiograph abnormalities were presented in 38 of 120. Pulmonary symptoms were presented in 10 of 120. Other extraintestinal complications were presented in 21 of 120. Conclusions: Pulmonary function impairment was more frequently than other extraintestinal complications in UC patients, which may be affected by sex, age, extent and course of disease. These results may be a scientific basis for the theory of exterior-interior correlation between Lung and Large intestine.
文摘The mutation sites of the four mutants F35Y, P40V, V45E and V45Y of cytochrome b 5 are located at the edge of the heme binding pocket. The solvent accessible areas of the “pocket interior” of the four mutants and the wild type cytochrome b 5 have been calculated based on their crystal structures at high resolution. The change in the hydrophobicity of the heme binding pocket resulting from the mutation can be quantitatively described using the difference of the solvent accessible area of the “pocket interior” of each mutant from that of the wild type cytochrome b 5. The influences of the hydrophobicity of the heme binding pocket on the protein stability and redox potential are discussed.