AIM:To quantitatively measure ocular morphological parameters of guinea pig with Python technology.METHODS:Thirty-six eyeballs of eighteen 3-weekold guinea pigs were measured with keratometer and photographed to obtai...AIM:To quantitatively measure ocular morphological parameters of guinea pig with Python technology.METHODS:Thirty-six eyeballs of eighteen 3-weekold guinea pigs were measured with keratometer and photographed to obtain the horizontal,coronal,and sagittal planes respectively.The corresponding photo pixels-actual length ratio was acquired by a proportional scale.The edge coordinates were identified artificially by ginput function.Circle and conic curve fitting were applied to fit the contour of the eyeball in the sagittal,coronal and horizontal view.The curvature,curvature radius,eccentricity,tilt angle,corneal diameter,and binocular separation angle were calculated according to the geometric principles.Next,the eyeballs were removed,canny edge detection was applied to identify the contour of eyeball in vitro.The results were compared between in vivo and in vitro.RESULTS:Regarding the corneal curvature and curvature radius on the horizontal and sagittal planes,no significant differences were observed among results in vivo,in vitro,and the keratometer.The horizontal and vertical binocular separation angles were 130.6°±6.39°and 129.8°±9.58°respectively.For the corneal curvature radius and eccentricity in vivo,significant differences were observed between horizontal and vertical planes.CONCLUSION:The Graphical interface window of Python makes up the deficiency of edge detection,which requires too much definition in Matlab.There are significant differences between guinea pig and human beings,such as exotropic eye position,oblique oval eyeball,and obvious discrepancy of binoculus.This study helps evaluate objectively the ocular morphological parameters of small experimental animals in emmetropization research.展开更多
AIM:To assess and compare the variations and agreements across different ocular biometric parameters using swept-source optical coherence tomography(SS-OCT)and Scheimpflug tomography in patients diagnosed with catarac...AIM:To assess and compare the variations and agreements across different ocular biometric parameters using swept-source optical coherence tomography(SS-OCT)and Scheimpflug tomography in patients diagnosed with cataract.METHODS:This prospective case series was conducted at Tianjin Medical University Eye Hospital.In total,212 eyes from 212 patients scheduled for phacoemulsification were included.Eyes were evaluated preoperatively using two SSOCT devices(IOLMaster700 and CASIA2)and Scheimpflug tomography(Pentacam).Central corneal thickness(CCT),anterior chamber depth(ACD),aqueous depth(AQD),white-to-white distance(WTW),flat simulated keratometry(Kf),steep simulated keratometry(Ks),mean keratometry(Km),and total corneal keratometry(TKm)were measured.Intraclass correlation coefficient(ICC),95%confidence intervals(CI)and limits of agreement(LoA)widths were conducted to assess differences and correlations between devices.RESULTS:All parameters,except for Ks,were significantly different.Pairwise comparison revealed no significant differences between keratometry obtained by IOLMaster 700 and Pentacam.LoA widths of all paired comparisons for Ks were>0.80 D.Except for WTW between IOLMaster 700 and CASIA2 and between CASIA2 and Pentacam,other Pearson’s coefficients between devices showed a strong correlation(all r>0.95).The ICC of WTW(ICC=0.438,95%CI 0.167-0.625)showed poor reliability.The reliability of CCT,ACD,and AQD was excellent(all ICC>0.95),whereas that of TKm was good(ICC=0.827,95%CI 0.221-0.939).A significant linear correlation was also observed among devices.CONCLUSION:The ocular parameters derived from the use of IOLMaster700,CASIA2,and Pentacam exhibit significant discrepancies;as such,measurements from these devices should not be deemed as interchangeable.展开更多
Chronic hepatitis B causes a liver disease characterized by inflammation of the liver parenchyma. The aim of this study was to investigate the evolution of biological parameters in patients treated with Tenofovir for ...Chronic hepatitis B causes a liver disease characterized by inflammation of the liver parenchyma. The aim of this study was to investigate the evolution of biological parameters in patients treated with Tenofovir for chronic B infection at the Commune V referral health center in Bamako. We obtained a prevalence of 14.15%. The most represented age group was 31 - 40 years, with 36.8%. The sex ratio was 1.44 in favour of men. Viral load was undetectable after 18 months of treatment in 25 patients (42.37%). Tenofovir, the 1st-line drug in Mali, is effective on the biological parameters monitored in patients.展开更多
AIM:To analyze and compare the differences among ocular biometric parameters in Han and Uyghur populations undergoing cataract surgery.METHODS:In this hospital-based prospective study,410 patients undergoing cataract ...AIM:To analyze and compare the differences among ocular biometric parameters in Han and Uyghur populations undergoing cataract surgery.METHODS:In this hospital-based prospective study,410 patients undergoing cataract surgery(226 Han patients in Tianjin and 184 Uyghur patients in Xinjiang)were enrolled.The differences in axial length(AL),anterior chamber depth(ACD),keratometry[steep K(Ks)and flat K(Kf)],and corneal astigmatism(CA)measured using IOL Master 700 were compared between Han and Uyghur patients.RESULTS:The average age of Han patients was higher than that of Uyghur patients(70.22±8.54 vs 63.04±9.56y,P<0.001).After adjusting for age factors,Han patients had longer AL(23.51±1.05 vs 22.86±0.92 mm,P<0.001),deeper ACD(3.06±0.44 vs 2.97±0.37 mm,P=0.001),greater Kf(43.95±1.40 vs 43.42±1.69 D,P=0.001),steeper Ks(45.00±1.47 vs 44.26±1.71 D,P=0.001),and higher CA(1.04±0.68 vs 0.79±0.65,P=0.025)than Uyghur patients.Intra-ethnic male patients had longer AL,deeper ACD,and lower keratometry than female patients;however,CA between the sexes was almost similar.In the correlation analysis,we observed a positive correlation between AL and ACD in patients of both ethnicities(rHan=0.48,rUyghur=0.44,P<0.001),while AL was negatively correlated with Kf(rHan=-0.42,rUyghur=-0.64,P<0.001)and Ks(rHan=-0.38,rUyghur=-0.66,P<0.001).Additionally,Kf was positively correlated with Ks(rHan=0.89,rUyghur=0.93,P<0.001).CONCLUSION:There are differences in ocular biometric parameters between individuals of Han ethnicity in Tianjin and those of Uyghur ethnicity in Xinjiang undergoing cataract surgery.These ethnic variances can enhance our understanding of ocular diseases related to these parameters and provide guidance for surgical procedures.展开更多
AIM:To investigate the effects of diode laser treatment on ocular biometric parameters in premature infants with retinopathy of prematurity(ROP).METHODS:Premature infants who received diode laser treatment for ROP(n=6...AIM:To investigate the effects of diode laser treatment on ocular biometric parameters in premature infants with retinopathy of prematurity(ROP).METHODS:Premature infants who received diode laser treatment for ROP(n=68)and premature infants with spontaneous regressed ROP without treatment(n=50)were performed longitudinal ocular biometric measurements including anterior chamber depth,lens thickness and axial length as follows:1 d prior to laser treatment,and 3,6,9,and 12 mo after the laser treatment.RESULTS:The mean birth weight,gestational age and initial examination time values were 936.53±302.07 g,26.66±2.42 wk,36.26±2.73 wk in the treatment group and 959.78±260.08 g,27.28±2.10 wk,36.56±2.54 wk in the control group.There was no statistically significant difference in these demographic characteristics of the groups.Anterior chamber depth,lens thickness and axial length demonstrated statistically significant linear increases during the study period in the two groups(P<0.001 for each).There were no statistically significant differences between the two groups in terms of anterior chamber depth after laser treatment.Measurements of the lens thickness at 9 th and 12 th months(9 th month 3.70±0.22 vs 3.60±0.21 mm,P=0.017;12 th month 3.81±0.21 vs 3.69±0.22 mm,P=0.002)and the axial length at 12 th month(19.35±0.79 vs 19.13±0.54 mm,P=0.031)after laser treatment were statistically higher in the treatment group.CONCLUSION:Diode laser retinal photocoagulation treatment in premature infants seems to increase the lens thickness and axial length.展开更多
Comparing fat content with physiological status can throw light on the reproduction and feeding behavior of the fish. The biological data of 586 bigeye tuna were collected from the longline fishery in the waters of We...Comparing fat content with physiological status can throw light on the reproduction and feeding behavior of the fish. The biological data of 586 bigeye tuna were collected from the longline fishery in the waters of Western Central Indian Ocean from November, 2012 to March, 2013. The spatial or temporal distribution of the fat content, and the relationships of fat content with gender, round weight, gonadal maturity and fork length were analyzed. A generalized additive model(GAM) was used to analyze the relationships between fat content and fork length(FL), gonadosomatic index(GSI), condition factor(K), and somatic index(SI). Results showed that: 1) the fat content of bigeye tuna was in the range of 3.1%–27.1% with the average 12.8%; 2) there were no significant geographical differences of average fat content(P > 0.05) among 1? squares in general; 3) there were no significant differences(P > 0.05) of the fat content for different genders, months, or gonad maturity stages; 4) there was an extremely significant correlation(P = 0.000) between fat content and FL and GSI. There was no significant correlation(P = 0.051) between fat content and K. There was a significant correlation(P = 0.003) between fat content and SI. The results of this study suggest that the fat content of the matured fish was relatively stable. The survey area was in a spawning region, and the survey period was the spawning season for bigeye tuna.展开更多
AIM: To assess and compare the impact of a daily disposable contact lens(CL) with high water content on the ocular surface and comfort of the presbyopic and nonpresbyopic population after one day of use. METHODS: Tota...AIM: To assess and compare the impact of a daily disposable contact lens(CL) with high water content on the ocular surface and comfort of the presbyopic and nonpresbyopic population after one day of use. METHODS: Totally 20 presbyopes and 30 non-presbyopes non-contact wearers were fitted with nesofilcon A CLs. CL thickness was measured to assess material stability during daily wear, and ocular surface parameters were also assessed. Optical quality was analyzed for all cases. In addition, CL comfort was rated.RESULTS: No significant differences were found in CL thickness, tear film osmolarity, average tear break-up time, bulbar redness, central corneal thickness, corneal volume, root-mean-square of higher-order aberrations(RMS of HOAs) and vertical and horizontal coma, either as a function of the group or time of use. A significant decrease in tear meniscus height and first break-up of the tear film was found in the presbyopic group(P=0.038; P=0.007 respectively). A decrease in spherical aberration coefficient was found after CL insertion(P=0.031 monofocal CL; P=0.023 low addition multifocal CL; P=0.016 high addition multifocal CL). Multifocal CL were thicker than monofocal CL(P=0.045). Comparison between groups showed more discomfort in presbyopes than non-presbyopes(P=0.003).CONCLUSION: This study evidence that the behavior of the daily disposable CL with high water content seems to be stable during the day of use. Ocular parameters measured during wear show that CL behavior is the same for presbyopes and non-presbyopes, being more uncomfortable for presbyopes.展开更多
Background With aging, the human fracture risk gradually increase. This is mainly due to the corresponding changes of the biomechanical parameters of human bone presents with aging. We measured the microstructural par...Background With aging, the human fracture risk gradually increase. This is mainly due to the corresponding changes of the biomechanical parameters of human bone presents with aging. We measured the microstructural parameters of lumbar bone from women in several age groups by micro-computed tomography and scanning electron microscopy. We observed changes in lumbar cancellous bone mineral density and in biomechanical parameters with aging to elucidate the relationship between age and risk of fracture. We provide theoretical support for human pathology, fracture risk increased with age and the individualized of each age group.展开更多
According to the data observed in a China- Japan Joint Investigation, the parameters of an ecosystem dynamics model (Qiao et al., 2000) were optimized. The values of eighteen parameters for the model were obtained, wi...According to the data observed in a China- Japan Joint Investigation, the parameters of an ecosystem dynamics model (Qiao et al., 2000) were optimized. The values of eighteen parameters for the model were obtained, with nutrient half saturation constant, Kn= 1.4μmol/dm3, Kp = 0.129 μmol/dm3 and K3= 1. 16μmol/dm3 for the diatom and Kn= 0.345μmol/dm3, Kp=0. 113μmol/dm3 for the flagellate. The proposals to set up a function for this multiple objective problem were discussed in detail.展开更多
Two-spotted spider mite, Tetranychus urticae Koch, is one of the important pests of bean, which can cause severe damages on it. Silicon is one of the micronutrient elements, as its spray on the leaves can decrease the...Two-spotted spider mite, Tetranychus urticae Koch, is one of the important pests of bean, which can cause severe damages on it. Silicon is one of the micronutrient elements, as its spray on the leaves can decrease the population of the pest. In this research, the impact of four different doses of Si (0, 1, 1/5, 2 ppm) was investigated on biological and population growth parameters of T. urticae. The experiments were carried out in Petri dishes in an incubator at 25°C ± 2°C, 65% ± 5% RH and 16 L: 8 D. The duration of developmental stage was significantly affected by Si dose. The longest immature period, the shortest longevity of females and the shortest oviposition period were obtained at 2 ppm. In addition, Si dose significantly affected population growth parameters of the mite. The intrinsic rate of natural increase (rm) of the mite ranged from 0.246 to 0.215 day which lowest and the highest values were at 2 ppm and control plants, respectively. The lowest net reproductive rate (R0) and finite rate of increase (λ) of the mite and the highest value of mean generation time (T) and doubling time (DT) were estimated at 2 ppm. The results of this peruse represented that 2 ppm had better potential for decreasing the population of the two-spotted spider mite, and it can be used in the mite integrated pest management programs.展开更多
基金Supported by the National Natural Science Foundation of China(No.81400428)Self-selected Projects of Shanghai Children’s Hospital(No.2020R124)Shanghai Children’s Hospital Hospital-level Project Clinical Research Cultivation Special Focus Project(No.2021YLYZ03).
文摘AIM:To quantitatively measure ocular morphological parameters of guinea pig with Python technology.METHODS:Thirty-six eyeballs of eighteen 3-weekold guinea pigs were measured with keratometer and photographed to obtain the horizontal,coronal,and sagittal planes respectively.The corresponding photo pixels-actual length ratio was acquired by a proportional scale.The edge coordinates were identified artificially by ginput function.Circle and conic curve fitting were applied to fit the contour of the eyeball in the sagittal,coronal and horizontal view.The curvature,curvature radius,eccentricity,tilt angle,corneal diameter,and binocular separation angle were calculated according to the geometric principles.Next,the eyeballs were removed,canny edge detection was applied to identify the contour of eyeball in vitro.The results were compared between in vivo and in vitro.RESULTS:Regarding the corneal curvature and curvature radius on the horizontal and sagittal planes,no significant differences were observed among results in vivo,in vitro,and the keratometer.The horizontal and vertical binocular separation angles were 130.6°±6.39°and 129.8°±9.58°respectively.For the corneal curvature radius and eccentricity in vivo,significant differences were observed between horizontal and vertical planes.CONCLUSION:The Graphical interface window of Python makes up the deficiency of edge detection,which requires too much definition in Matlab.There are significant differences between guinea pig and human beings,such as exotropic eye position,oblique oval eyeball,and obvious discrepancy of binoculus.This study helps evaluate objectively the ocular morphological parameters of small experimental animals in emmetropization research.
基金Supported by Tianjin Key Medical Discipline (Specialty) Construction Project (No.TJYXZDXK-037A)Weifang Science and Technology Bureau Project (No.2020YX065).
文摘AIM:To assess and compare the variations and agreements across different ocular biometric parameters using swept-source optical coherence tomography(SS-OCT)and Scheimpflug tomography in patients diagnosed with cataract.METHODS:This prospective case series was conducted at Tianjin Medical University Eye Hospital.In total,212 eyes from 212 patients scheduled for phacoemulsification were included.Eyes were evaluated preoperatively using two SSOCT devices(IOLMaster700 and CASIA2)and Scheimpflug tomography(Pentacam).Central corneal thickness(CCT),anterior chamber depth(ACD),aqueous depth(AQD),white-to-white distance(WTW),flat simulated keratometry(Kf),steep simulated keratometry(Ks),mean keratometry(Km),and total corneal keratometry(TKm)were measured.Intraclass correlation coefficient(ICC),95%confidence intervals(CI)and limits of agreement(LoA)widths were conducted to assess differences and correlations between devices.RESULTS:All parameters,except for Ks,were significantly different.Pairwise comparison revealed no significant differences between keratometry obtained by IOLMaster 700 and Pentacam.LoA widths of all paired comparisons for Ks were>0.80 D.Except for WTW between IOLMaster 700 and CASIA2 and between CASIA2 and Pentacam,other Pearson’s coefficients between devices showed a strong correlation(all r>0.95).The ICC of WTW(ICC=0.438,95%CI 0.167-0.625)showed poor reliability.The reliability of CCT,ACD,and AQD was excellent(all ICC>0.95),whereas that of TKm was good(ICC=0.827,95%CI 0.221-0.939).A significant linear correlation was also observed among devices.CONCLUSION:The ocular parameters derived from the use of IOLMaster700,CASIA2,and Pentacam exhibit significant discrepancies;as such,measurements from these devices should not be deemed as interchangeable.
文摘Chronic hepatitis B causes a liver disease characterized by inflammation of the liver parenchyma. The aim of this study was to investigate the evolution of biological parameters in patients treated with Tenofovir for chronic B infection at the Commune V referral health center in Bamako. We obtained a prevalence of 14.15%. The most represented age group was 31 - 40 years, with 36.8%. The sex ratio was 1.44 in favour of men. Viral load was undetectable after 18 months of treatment in 25 patients (42.37%). Tenofovir, the 1st-line drug in Mali, is effective on the biological parameters monitored in patients.
基金Supported by Tianjin Higher Education Commission Science and Technology Development Fund Project(No.2022ZD057)Tianjin Binhai New Area Health Commission Science and Technology Project(No.2022BWKZ003)+4 种基金Tianjin Key Laboratory of Retinal Function and Disease Open Project(No.2021tjswmm002)Tianjin Health Researh(No.TJWJ2023ZD002)General Project of Natural Science Foundation of Xinjiang Uygur Autonomous Region(No.2020D01A06)Special Fund for Youth of Clinical Research Center in Tianjin Medical University Eye Hospital(No.2020QN02)Tianjin Key Medical Discipline(Specialty)Construction Project(No.TJYXZDXK-037A)。
文摘AIM:To analyze and compare the differences among ocular biometric parameters in Han and Uyghur populations undergoing cataract surgery.METHODS:In this hospital-based prospective study,410 patients undergoing cataract surgery(226 Han patients in Tianjin and 184 Uyghur patients in Xinjiang)were enrolled.The differences in axial length(AL),anterior chamber depth(ACD),keratometry[steep K(Ks)and flat K(Kf)],and corneal astigmatism(CA)measured using IOL Master 700 were compared between Han and Uyghur patients.RESULTS:The average age of Han patients was higher than that of Uyghur patients(70.22±8.54 vs 63.04±9.56y,P<0.001).After adjusting for age factors,Han patients had longer AL(23.51±1.05 vs 22.86±0.92 mm,P<0.001),deeper ACD(3.06±0.44 vs 2.97±0.37 mm,P=0.001),greater Kf(43.95±1.40 vs 43.42±1.69 D,P=0.001),steeper Ks(45.00±1.47 vs 44.26±1.71 D,P=0.001),and higher CA(1.04±0.68 vs 0.79±0.65,P=0.025)than Uyghur patients.Intra-ethnic male patients had longer AL,deeper ACD,and lower keratometry than female patients;however,CA between the sexes was almost similar.In the correlation analysis,we observed a positive correlation between AL and ACD in patients of both ethnicities(rHan=0.48,rUyghur=0.44,P<0.001),while AL was negatively correlated with Kf(rHan=-0.42,rUyghur=-0.64,P<0.001)and Ks(rHan=-0.38,rUyghur=-0.66,P<0.001).Additionally,Kf was positively correlated with Ks(rHan=0.89,rUyghur=0.93,P<0.001).CONCLUSION:There are differences in ocular biometric parameters between individuals of Han ethnicity in Tianjin and those of Uyghur ethnicity in Xinjiang undergoing cataract surgery.These ethnic variances can enhance our understanding of ocular diseases related to these parameters and provide guidance for surgical procedures.
文摘AIM:To investigate the effects of diode laser treatment on ocular biometric parameters in premature infants with retinopathy of prematurity(ROP).METHODS:Premature infants who received diode laser treatment for ROP(n=68)and premature infants with spontaneous regressed ROP without treatment(n=50)were performed longitudinal ocular biometric measurements including anterior chamber depth,lens thickness and axial length as follows:1 d prior to laser treatment,and 3,6,9,and 12 mo after the laser treatment.RESULTS:The mean birth weight,gestational age and initial examination time values were 936.53±302.07 g,26.66±2.42 wk,36.26±2.73 wk in the treatment group and 959.78±260.08 g,27.28±2.10 wk,36.56±2.54 wk in the control group.There was no statistically significant difference in these demographic characteristics of the groups.Anterior chamber depth,lens thickness and axial length demonstrated statistically significant linear increases during the study period in the two groups(P<0.001 for each).There were no statistically significant differences between the two groups in terms of anterior chamber depth after laser treatment.Measurements of the lens thickness at 9 th and 12 th months(9 th month 3.70±0.22 vs 3.60±0.21 mm,P=0.017;12 th month 3.81±0.21 vs 3.69±0.22 mm,P=0.002)and the axial length at 12 th month(19.35±0.79 vs 19.13±0.54 mm,P=0.031)after laser treatment were statistically higher in the treatment group.CONCLUSION:Diode laser retinal photocoagulation treatment in premature infants seems to increase the lens thickness and axial length.
基金supported by the National High Technology Research and Development Program of China (863 program, No. 2012 AA092302)The Specialized Research Fund for the Doctoral Program of Higher Educationn (No. 20113104 110004)+3 种基金Shanghai Municipal Education Commission Innovation Project (No. 12ZZ168)Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources (Shanghai Ocean University),Ministry of Education (No. A102091505037)Special funding for the development of science and technology of Shanghai Ocean University (No. A2020915200002)the Youth Scholars of Shanghai Higher Education Institutions (No. A1203514001014)
文摘Comparing fat content with physiological status can throw light on the reproduction and feeding behavior of the fish. The biological data of 586 bigeye tuna were collected from the longline fishery in the waters of Western Central Indian Ocean from November, 2012 to March, 2013. The spatial or temporal distribution of the fat content, and the relationships of fat content with gender, round weight, gonadal maturity and fork length were analyzed. A generalized additive model(GAM) was used to analyze the relationships between fat content and fork length(FL), gonadosomatic index(GSI), condition factor(K), and somatic index(SI). Results showed that: 1) the fat content of bigeye tuna was in the range of 3.1%–27.1% with the average 12.8%; 2) there were no significant geographical differences of average fat content(P > 0.05) among 1? squares in general; 3) there were no significant differences(P > 0.05) of the fat content for different genders, months, or gonad maturity stages; 4) there was an extremely significant correlation(P = 0.000) between fat content and FL and GSI. There was no significant correlation(P = 0.051) between fat content and K. There was a significant correlation(P = 0.003) between fat content and SI. The results of this study suggest that the fat content of the matured fish was relatively stable. The survey area was in a spawning region, and the survey period was the spawning season for bigeye tuna.
文摘AIM: To assess and compare the impact of a daily disposable contact lens(CL) with high water content on the ocular surface and comfort of the presbyopic and nonpresbyopic population after one day of use. METHODS: Totally 20 presbyopes and 30 non-presbyopes non-contact wearers were fitted with nesofilcon A CLs. CL thickness was measured to assess material stability during daily wear, and ocular surface parameters were also assessed. Optical quality was analyzed for all cases. In addition, CL comfort was rated.RESULTS: No significant differences were found in CL thickness, tear film osmolarity, average tear break-up time, bulbar redness, central corneal thickness, corneal volume, root-mean-square of higher-order aberrations(RMS of HOAs) and vertical and horizontal coma, either as a function of the group or time of use. A significant decrease in tear meniscus height and first break-up of the tear film was found in the presbyopic group(P=0.038; P=0.007 respectively). A decrease in spherical aberration coefficient was found after CL insertion(P=0.031 monofocal CL; P=0.023 low addition multifocal CL; P=0.016 high addition multifocal CL). Multifocal CL were thicker than monofocal CL(P=0.045). Comparison between groups showed more discomfort in presbyopes than non-presbyopes(P=0.003).CONCLUSION: This study evidence that the behavior of the daily disposable CL with high water content seems to be stable during the day of use. Ocular parameters measured during wear show that CL behavior is the same for presbyopes and non-presbyopes, being more uncomfortable for presbyopes.
文摘Background With aging, the human fracture risk gradually increase. This is mainly due to the corresponding changes of the biomechanical parameters of human bone presents with aging. We measured the microstructural parameters of lumbar bone from women in several age groups by micro-computed tomography and scanning electron microscopy. We observed changes in lumbar cancellous bone mineral density and in biomechanical parameters with aging to elucidate the relationship between age and risk of fracture. We provide theoretical support for human pathology, fracture risk increased with age and the individualized of each age group.
文摘According to the data observed in a China- Japan Joint Investigation, the parameters of an ecosystem dynamics model (Qiao et al., 2000) were optimized. The values of eighteen parameters for the model were obtained, with nutrient half saturation constant, Kn= 1.4μmol/dm3, Kp = 0.129 μmol/dm3 and K3= 1. 16μmol/dm3 for the diatom and Kn= 0.345μmol/dm3, Kp=0. 113μmol/dm3 for the flagellate. The proposals to set up a function for this multiple objective problem were discussed in detail.
文摘Two-spotted spider mite, Tetranychus urticae Koch, is one of the important pests of bean, which can cause severe damages on it. Silicon is one of the micronutrient elements, as its spray on the leaves can decrease the population of the pest. In this research, the impact of four different doses of Si (0, 1, 1/5, 2 ppm) was investigated on biological and population growth parameters of T. urticae. The experiments were carried out in Petri dishes in an incubator at 25°C ± 2°C, 65% ± 5% RH and 16 L: 8 D. The duration of developmental stage was significantly affected by Si dose. The longest immature period, the shortest longevity of females and the shortest oviposition period were obtained at 2 ppm. In addition, Si dose significantly affected population growth parameters of the mite. The intrinsic rate of natural increase (rm) of the mite ranged from 0.246 to 0.215 day which lowest and the highest values were at 2 ppm and control plants, respectively. The lowest net reproductive rate (R0) and finite rate of increase (λ) of the mite and the highest value of mean generation time (T) and doubling time (DT) were estimated at 2 ppm. The results of this peruse represented that 2 ppm had better potential for decreasing the population of the two-spotted spider mite, and it can be used in the mite integrated pest management programs.