This article provides a brief overview of various approaches that may be utilized for the analysis of human semen test results. Reference intervals are the most widely used tool for the interpretation of clinical labo...This article provides a brief overview of various approaches that may be utilized for the analysis of human semen test results. Reference intervals are the most widely used tool for the interpretation of clinical laboratory results. Reference interval development has classically relied on concepts elaborated by the International Federation of Clinical Chemistry Expert Panel on Reference Values during the 1980s. These guidelines involve obtaining and classifying samples from a healthy population of at least 120 individuals and then identifying the outermost 5% of observations to use in defining limits for two-sided or one-sided reference intervals. More recently, decision limits based on epidemiological outcome analysis have also been introduced to aid in test interpretation. The reference population must be carefully defined on the basis of the intended clinical use of the underlying test. To determine appropriate reference intervals for use in male fertility assessment, a reference population of men with documented time to pregnancy of 〈 12 months would be most suitable. However, for epidemiological assessment of semen testing results, a reference population made up ofunselected healthy men would be preferred. Although reference and decision limits derived for individual semen analysis test results will undoubtedly be the interpretational tools of choice in the near future, in the long term, multivariate methods for the interpretation of semen analysis alone or in combination with information from the female partner seem to represent better means for assessing the likelihood of achieving a successful pregnancy in a subfertile couple.展开更多
The reference values of serum perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) concentrations were evaluated based on the human blood samples collected from Kashi, Xinjiang. And human serum samples of fa...The reference values of serum perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) concentrations were evaluated based on the human blood samples collected from Kashi, Xinjiang. And human serum samples of family members from Liaoning were evaluated for levels of PFOS and PFOA with the purpose to compare exposure pathways for family members. Among the 110 blood specimens from Kashi, the detection frequency of PFOS and PFOA was 93% and 6%, respectively. Reference values of serum PFOS, evaluated as the 90th percentiles of the concentrations, were determined to be 6.44 μg/L. Significant positive correlations were observed for serum levels of PFOS and PFOA among family members in Liaoning. Specially, stronger correlation between mother and offspring was observed than that between father and offspring. And stronger correlation of serum PFOS and PFOA levels was observed among fam- ily members in rural areas than those in big and small-medium cities. Difference in the association of serum PFOS and PFOA level among family members suggested that exposure in the outdoor and working environment of different oc- cupations should be evaluated. Present study provides reference values for exposure assessment in China and potential pathways of human exposure to PFOS and PFOA.展开更多
Sperm head morphology is crucial for male factor infertility diagnosis and assessment of male reproductive potential.Severalcriteria are available to analyze sperm head morphology,but they are limited by poor methodol...Sperm head morphology is crucial for male factor infertility diagnosis and assessment of male reproductive potential.Severalcriteria are available to analyze sperm head morphology,but they are limited by poor methodology comparability and populationapplicability.This study aimed to explore comprehensive and new normal morphometric reference values for spermatozoa heads infertile Asian males.An automated sperm morphology analysis system captured 23152 stained spermatozoa from confirmed fertilemales.Of these samples,1856 sperm head images were annotated by three experienced laboratory technicians as“normal”.Weemployed 14 novel morphometric features to describe sperm head size(head length,head width,length/width ratio,and girth),shape(ellipse intersection over union,girth intersection over union,short-axis symmetry,and long-axis symmetry),area(head,acrosome,postacrosomal areas,and acrosome area ratio),and degrees of acrosome and nuclear uniformity.This straight-forwardmethod for the morphometric analysis of sperm by accurate visual measurements is clinically applicable.The measured parameterspresent valuable information to establish morphometric reference intervals for normal sperm heads in fertile Asian males.Thepresented detailed measurement data will be valuable for interlaboratory comparisons and technician training.In vitro fertilizationand andrology laboratory technicians can use these parameters to perform objective morphology evaluation when assessing malefertilization potential.展开更多
Background:Biochemical and hematological parameters are important tools for assessing the physiological profile of vital organs,and can be recorded to create reference values used for clinical diagnosis of diseases.Ma...Background:Biochemical and hematological parameters are important tools for assessing the physiological profile of vital organs,and can be recorded to create reference values used for clinical diagnosis of diseases.Many research laboratories lack the means to establish their own set of reference parameters for use in their research,and while there are articles in the literature that discuss laboratory parameters for healthy BALB/c mice,few studies address the evaluation of these parameters in pathological situations,such as in mice inoculated with Ehrlich tumor.Method:BALB/c-FMABC mice previously inoculated with Ehrlich tumor were maintained under appropriate conditions.Blood samples were taken for analysis of hematological parameters using automated and semi-automated equipment to create a set of the animal welfare parameters for evaluation.Result:Results were obtained for all the hematological parameters for all groups analyzed.These showed:statistically significant differences between the initial and final tumor weight;comparable initial tumour volume and weight;an increase in leukocytes in the 7-day group with a characteristic predominance of lymphocytes and neutrophils;statistically significant changes in RDW in the 21-day group and in the welfare parameters in the 28-day group.Conclusion:The study successfully defined and established reference values for hematological and welfare parameters for all groups analyzed.展开更多
Background: In order to detect possible abnormalities of the spine posture of an individual patient, it is mandatory to dispose of adequate reference values based on measurements in a normal, symptom-free population. ...Background: In order to detect possible abnormalities of the spine posture of an individual patient, it is mandatory to dispose of adequate reference values based on measurements in a normal, symptom-free population. The Diers formetric?system allows for non-invasive and accurate assessment of the vertebral column based on the registration of external aspect of the back surface using the Moiré principle. Objective: To create a qualitative spine profile based on the percentile ranking of measurements obtained by the Diers formetric system taking into account possible confounding factors. Materials and Methods: Statistical analysis of formetric recordings in 216 symptom-free volunteers. Results: Maximal kyphotic angle, maximal scoliotic angle, sagittal imbalance, flèche cervicale, and pelvic inclination are significantly influenced by gender and by body mass index (BMI). A synoptic chart was created presenting the percentile ranking taking into account gender and BMI. The percentile ranking was summarized in both a table with colour code and depicted in a histogram of the individual’s Qualitative Spine Profile (QSP). Clinical Significance: Percentile ranking and the Quantitative Spine Profile taking into account gender and BMI should permit a more precise and reliable assessment of possible posture deviations related to the patient’s complaints, and may assist the therapist in selecting the best mode of treatment.展开更多
Background: Lack of available reference values in a research setting under local conditions can be a drawback for beginners, as the accuracy of data from control samples cannot be checked at the beginning of a researc...Background: Lack of available reference values in a research setting under local conditions can be a drawback for beginners, as the accuracy of data from control samples cannot be checked at the beginning of a research project. This affects comparisons with data from test samples. To avoid these complications in their research projects,beginners tend to have a greater number of animals in the control group compared to test groups in order to have control group measurements within 2 SDs of the mean.Methods: As non-availability of reference values was a long-felt need, the described project was conducted in order to establish a reference database for selected haematological, biochemical and physiological parameters using apparently healthy Sprague-Dawley rats bred in the Animal House of Faculty of Medicine, University of Colombo(UCFM).Results: Differences in mean values of packed cell volume(PCV), mean corpuscular volume(MCV) and mean corpuscular hemoglobin concentration(MCHC), serum creatinine and blood glucose levels between the two genders were statistically significant. Lipid profile measurements did not differ significantly between genders, but mean and median values of triglycerides(TG) between male and female rats showed a difference of more than 10 mg/dL. The liver enzymes alkaline phosphatase(AP)and aspartate aminotransferase(AST) were also statistically significantly different between sexes. Despite wide variation in mean alanine aminotransferase(ALT)between sexes, the difference was not statistically significant.Conclusion: The findings of this project should support to a certain extent the"Reduction" aspect of the 3 Rs concept of Russell and Burch by reducing the number of Sprague-Dawley rats used in future research projects at UCFM.展开更多
With his publication in 1873 [1] J. W. Gibbs formulated the thermodynamic theory. It describes almost all macroscopically observed properties of matter and could also describe all phenomena if only the free energy U -...With his publication in 1873 [1] J. W. Gibbs formulated the thermodynamic theory. It describes almost all macroscopically observed properties of matter and could also describe all phenomena if only the free energy U - ST were explicitly known numerically. The thermodynamic uniqueness of the free energy obviously depends on that of the internal energy U and the entropy S, which in both cases Gibbs had been unable to specify. This uncertainty, lasting more than 100 years, was not eliminated either by Nernst’s hypothesis S = 0 at T = 0. This was not achieved till the advent of additional proof of the thermodynamic relation U = 0 at T = Tc. It is noteworthy that from purely thermodynamic consideration of intensive and extensive quantities it is possible to derive both Gibbs’s formulations of entropy and internal energy and their now established absolute reference values. Further proofs of the vanishing value of the internal energy at the critical point emanate from the fact that in the case of the saturated fluid both the internal energy and its phase-specific components can be represented as functions of the evaporation energy. Combining the differential expressions in Gibbs’s equation for the internal energy, d(μ/T)/d(1/T) and d(p/T)/d(1/T), to a new variable d(μ/T)/d(p/T) leads to a volume equation with the lower limit vc as boundary condition. By means of a variable transformation one obtains a functional equation for the sum of two dimensionless variables, each of them being related to an identical form of local interaction forces between fluid particles, but the different particle densities in the vapor and liquid spaces produce different interaction effects. The same functional equation also appears in another context relating to the internal energy. The solution of this equation can be given in analytic form and has been published [2] [3]. Using the solutions emerging in different sets of problems, one can calculate absolutely the internal energy as a function of temperature-dependent, phase-specific volumes and vapor pressure.展开更多
BACKGROUND Gait is influenced by race,age,and diseases type.Reference values for gait are closely related to numerous health outcomes.To gain a comprehensive understanding of gait patterns,particularly in relation to ...BACKGROUND Gait is influenced by race,age,and diseases type.Reference values for gait are closely related to numerous health outcomes.To gain a comprehensive understanding of gait patterns,particularly in relation to race-related pathologies and disorders,it is crucial to establish reference values for gait in daily life considering sex and age.Therefore,our objective was to present sex and age-based reference values for gait in daily life,providing a valuable foundation for further research and clinical applications.AIM To establish reference values for lower extremity joint kinematics and kinetics during gait in asymptomatic adult women and men.METHODS Spatiotemporal,kinematics and kinetics parameters were measured in 171 healthy adults(70 males and 101 females)using the computer-aided soft tissue foot model.Full curve statistical parametric mapping was performed using independent and paired-samples t-tests.RESULTS Compared with females,males required more time(cycle time,double-limb support time,stance time,swing time,and stride time),and the differences were statistically significant.In addition,the step and stride lengths of males were longer.Compared to males,female cadence was faster,and statures-per-second and stride-per-minute were higher.There were no statistical differences in speed and stride width between the two groups.After adjusting for height,it was observed that women walked significantly faster than men,and they also had a higher cadence.However,in terms of step length,stride length,and stride width,both genders exhibited similarities.CONCLUSION We established reference values for gait speed and spatiotemporal gait parameters in Chinese university students.This contributes to a valuable database for gait assessment and evaluation of preventive or rehabilitative programs.展开更多
Background: 1) To determine forced vital capacity (FVC) and forced expiratory volume in one second (FEV) for Beninese individuals of both sexes aged 17 - 20 years;2) Compare the observed values to those calculated bas...Background: 1) To determine forced vital capacity (FVC) and forced expiratory volume in one second (FEV) for Beninese individuals of both sexes aged 17 - 20 years;2) Compare the observed values to those calculated based on the algorithms of the spirometer used. Materials and Methods: The FVC and FEV values were first measured using a Micro Quark spirometer and then calculated from equations for the European Respiratory Society-93 (ERS-93) in 148 subjects, including 46 girls. In each age group, the measured values for the height of the subjects were considered the only variables used to calculate the equations for FVC and FEV with their 95% confidence intervals. The means of the FEV and FVC values were obtained by univariate analysis. Results: The calculated FEV and FVC values were significantly higher (p Conclusion: The correction factors incorporated in spirometers imported from Europe no longer seem appropriate to measure the physical characteristics of African subjects. The differences between the two methods of assessment should be used as new ethnic correction factors.展开更多
Objective To evaluate the validity of current spirometric reference values for healthy adults in Shanghai.Methods Healthy non-smoking adults without respiratory diseases were randomly enrolled in the study.Gender,age,...Objective To evaluate the validity of current spirometric reference values for healthy adults in Shanghai.Methods Healthy non-smoking adults without respiratory diseases were randomly enrolled in the study.Gender,age,standing height,body weight and spirometric parameters were obtained.The parameters were compared with reference values from current prediction equations with or without conversion factors.Results A total of 127 healthy adults (60 males and 67 females) aged 18-57 years participated in the study.In the study,pulmonary function parameters of healthy adults,especially of female adults were higher than predicted values,according to prediction equations from Chinese subjects in Shanghai.There were discrepancies between measuring values and reference values from foreign prediction equations with or without conversion factors.Conclusion Spirometric parameters of healthy adults,especially female population in Shanghai might be underestimated by present reference values from Chinese subjects.Foreign reference values and their conversion factors are not able to match measuring values.Validity of spirometric reference values for adults in Shanghai should be reassessed.展开更多
随着我国轨道交通网络飞速扩张,其巨大运营能耗,尤其是照明系统能耗,成为运营成本控制的重点。为实现绿色、低碳、高效的运营目标,智能照明控制技术的研究与应用至关重要。本文重点探讨基于电力载波通信(Power Line Communication,PLC)...随着我国轨道交通网络飞速扩张,其巨大运营能耗,尤其是照明系统能耗,成为运营成本控制的重点。为实现绿色、低碳、高效的运营目标,智能照明控制技术的研究与应用至关重要。本文重点探讨基于电力载波通信(Power Line Communication,PLC)技术的照明智控系统在轨道交通领域的节能应用。首先,分析轨道交通站点照明系统的特点与能耗现状,深入阐述PLC技术的基本原理及其相较其他技术的全方位优势,特别是在施工简便性、材料节省、运维管理智能化方面的突出价值。其次,设计出一套适用于地铁站站厅、站台等场景的基于PLC的照明智控系统架构,详细介绍其硬件组成、通信协议和智能控制策略(包括分区控制、定时控制、光感联动及人流感应控制)。最后,通过在温州轨道交通某站点试点案例分析,对比系统改造前后的能耗数据,证明该系统在显著降低照明能耗(平均节能率超30%)、节约改造材料与施工成本、实现运维管理数字化方面的卓越性,为PLC技术在轨道交通节能领域的规模化推广提供强有力的理论依据和实践参考。展开更多
A research is conducted on the relationship between the normal reference value of 20,475 examples of hemoglobin of young women and five geographical factors in 208 areas in China, the normal reference...A research is conducted on the relationship between the normal reference value of 20,475 examples of hemoglobin of young women and five geographical factors in 208 areas in China, the normal reference value is determined by the hemoglobincyanide method. It is found that the correlation of geographical factors and the normal reference value of hemoglobin of young women are quite significant (F=142.81). By using the method of multiple linear regression analysis, one regression equation is inferred. If geographical values are obtained in some areas, the normal reference value of hemoglobin of young women of this area can be reckoned by using the regression equation. Furthermore, depending on the geographical factors, China can be divided into six regions: Qinghai-Tibet (Qingzang) Plateau, Southwest, Northwest, Southeast, North and Northeast China.展开更多
AIM To describe the thromboelastography(TEG) "reference" values within a population of liver transplant(LT) candidates that underline the differences from healthy patients.METHODS Between 2000 and 2013, 261 ...AIM To describe the thromboelastography(TEG) "reference" values within a population of liver transplant(LT) candidates that underline the differences from healthy patients.METHODS Between 2000 and 2013, 261 liver transplant patients with a model for end-stage liver disease(MELD) score between 15 and 40 were studied. In particular the adult patients(aged 18-70 years) underwent to a first LT with a MELD score between 15 and 40 were included, while all patients with acute liver failure, congenital bleeding disorders, and anticoagulant and/or antiplatelet drug use were excluded. In this population of cirrhotic patients, preoperative haematological and coagulation laboratory tests were collected, and the pretransplant thromboelastographic parameters were studied and compared with the parameters measured in a previously studied population of 40 healthy subjects. The basal TEG parameters analysed in the cirrhotic population of liver candidates were as follows: Reaction time(r), coagulation time(k), Angle-Rate of polymerization of clot(α Angle), Maximum strenght of clot(MA), Amplitudes of the TEG tracing at 30 min and 60 min after MA is measured(A30 and A60), and Fibrinolysis at 30 and 60 min after MA(Ly30 and Ly60). The possible correlation between the distribution of the reference range and the gender, age, MELD score(higher or lower than 20) and indications for transplantation(liver pathology) were also investigated. In particular, a MELD cut-off value of 20 was chosen to verify the possible correlation between the thromboelastographic reference range and MELD score. RESULTS Most of the TEG reference values from patients with end-stage liver disease were significantly different from those measured in the healthy population and were outside the suggested normal ranges in up to 79.3% of subjects. Wide differences were found among all TEG variables, including r(41.5% of the values), k(48.6%), α(43.7%), MA(79.3%), A30(74.4%) and A60(80.9%), indicating a prevailing trend to hypocoagulability. The differences between the mean TEG values obtained from healthy subjects and the cirrhotic population were statistically significant for r(P = 0.039), k(P < 0.001), MA(P < 0.001), A30(P < 0.001), A60(P < 0.001) and Ly60(P = 0.038), indicating slower and less stable clot formation in the cirrhotic patients. In the cirrhotic population, 9.5% of patients had an r value shorter than normal, indicating a tendency for faster clot formation. Within the cirrhotic patient population, gender, age and the presence of hepatocellular carcinoma or alcoholic cirrhosis were not significantly associated with greater clot firmness or enhanced whole blood clot formation, whereas greater clot strength was associated with a MELD score < 20, hepatitis C virus and cholestaticrelated cirrhosis(P < 0.001; P = 0.013; P < 0.001).CONCLUSION The range and distribution of TEG values in cirrhotic patients differ from those of healthy subjects, suggesting that a specific thromboelastographic reference range is required for liver transplant candidates.展开更多
文摘This article provides a brief overview of various approaches that may be utilized for the analysis of human semen test results. Reference intervals are the most widely used tool for the interpretation of clinical laboratory results. Reference interval development has classically relied on concepts elaborated by the International Federation of Clinical Chemistry Expert Panel on Reference Values during the 1980s. These guidelines involve obtaining and classifying samples from a healthy population of at least 120 individuals and then identifying the outermost 5% of observations to use in defining limits for two-sided or one-sided reference intervals. More recently, decision limits based on epidemiological outcome analysis have also been introduced to aid in test interpretation. The reference population must be carefully defined on the basis of the intended clinical use of the underlying test. To determine appropriate reference intervals for use in male fertility assessment, a reference population of men with documented time to pregnancy of 〈 12 months would be most suitable. However, for epidemiological assessment of semen testing results, a reference population made up ofunselected healthy men would be preferred. Although reference and decision limits derived for individual semen analysis test results will undoubtedly be the interpretational tools of choice in the near future, in the long term, multivariate methods for the interpretation of semen analysis alone or in combination with information from the female partner seem to represent better means for assessing the likelihood of achieving a successful pregnancy in a subfertile couple.
文摘The reference values of serum perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) concentrations were evaluated based on the human blood samples collected from Kashi, Xinjiang. And human serum samples of family members from Liaoning were evaluated for levels of PFOS and PFOA with the purpose to compare exposure pathways for family members. Among the 110 blood specimens from Kashi, the detection frequency of PFOS and PFOA was 93% and 6%, respectively. Reference values of serum PFOS, evaluated as the 90th percentiles of the concentrations, were determined to be 6.44 μg/L. Significant positive correlations were observed for serum levels of PFOS and PFOA among family members in Liaoning. Specially, stronger correlation between mother and offspring was observed than that between father and offspring. And stronger correlation of serum PFOS and PFOA levels was observed among fam- ily members in rural areas than those in big and small-medium cities. Difference in the association of serum PFOS and PFOA level among family members suggested that exposure in the outdoor and working environment of different oc- cupations should be evaluated. Present study provides reference values for exposure assessment in China and potential pathways of human exposure to PFOS and PFOA.
基金supported by the National Natural Science Foundation of China(No.81974226,No.32171264,and No.81974365)the Sichuan Science and Technology Program(No.2021YFS0026 and No.2022YFS0045).
文摘Sperm head morphology is crucial for male factor infertility diagnosis and assessment of male reproductive potential.Severalcriteria are available to analyze sperm head morphology,but they are limited by poor methodology comparability and populationapplicability.This study aimed to explore comprehensive and new normal morphometric reference values for spermatozoa heads infertile Asian males.An automated sperm morphology analysis system captured 23152 stained spermatozoa from confirmed fertilemales.Of these samples,1856 sperm head images were annotated by three experienced laboratory technicians as“normal”.Weemployed 14 novel morphometric features to describe sperm head size(head length,head width,length/width ratio,and girth),shape(ellipse intersection over union,girth intersection over union,short-axis symmetry,and long-axis symmetry),area(head,acrosome,postacrosomal areas,and acrosome area ratio),and degrees of acrosome and nuclear uniformity.This straight-forwardmethod for the morphometric analysis of sperm by accurate visual measurements is clinically applicable.The measured parameterspresent valuable information to establish morphometric reference intervals for normal sperm heads in fertile Asian males.Thepresented detailed measurement data will be valuable for interlaboratory comparisons and technician training.In vitro fertilizationand andrology laboratory technicians can use these parameters to perform objective morphology evaluation when assessing malefertilization potential.
文摘Background:Biochemical and hematological parameters are important tools for assessing the physiological profile of vital organs,and can be recorded to create reference values used for clinical diagnosis of diseases.Many research laboratories lack the means to establish their own set of reference parameters for use in their research,and while there are articles in the literature that discuss laboratory parameters for healthy BALB/c mice,few studies address the evaluation of these parameters in pathological situations,such as in mice inoculated with Ehrlich tumor.Method:BALB/c-FMABC mice previously inoculated with Ehrlich tumor were maintained under appropriate conditions.Blood samples were taken for analysis of hematological parameters using automated and semi-automated equipment to create a set of the animal welfare parameters for evaluation.Result:Results were obtained for all the hematological parameters for all groups analyzed.These showed:statistically significant differences between the initial and final tumor weight;comparable initial tumour volume and weight;an increase in leukocytes in the 7-day group with a characteristic predominance of lymphocytes and neutrophils;statistically significant changes in RDW in the 21-day group and in the welfare parameters in the 28-day group.Conclusion:The study successfully defined and established reference values for hematological and welfare parameters for all groups analyzed.
文摘Background: In order to detect possible abnormalities of the spine posture of an individual patient, it is mandatory to dispose of adequate reference values based on measurements in a normal, symptom-free population. The Diers formetric?system allows for non-invasive and accurate assessment of the vertebral column based on the registration of external aspect of the back surface using the Moiré principle. Objective: To create a qualitative spine profile based on the percentile ranking of measurements obtained by the Diers formetric system taking into account possible confounding factors. Materials and Methods: Statistical analysis of formetric recordings in 216 symptom-free volunteers. Results: Maximal kyphotic angle, maximal scoliotic angle, sagittal imbalance, flèche cervicale, and pelvic inclination are significantly influenced by gender and by body mass index (BMI). A synoptic chart was created presenting the percentile ranking taking into account gender and BMI. The percentile ranking was summarized in both a table with colour code and depicted in a histogram of the individual’s Qualitative Spine Profile (QSP). Clinical Significance: Percentile ranking and the Quantitative Spine Profile taking into account gender and BMI should permit a more precise and reliable assessment of possible posture deviations related to the patient’s complaints, and may assist the therapist in selecting the best mode of treatment.
文摘Background: Lack of available reference values in a research setting under local conditions can be a drawback for beginners, as the accuracy of data from control samples cannot be checked at the beginning of a research project. This affects comparisons with data from test samples. To avoid these complications in their research projects,beginners tend to have a greater number of animals in the control group compared to test groups in order to have control group measurements within 2 SDs of the mean.Methods: As non-availability of reference values was a long-felt need, the described project was conducted in order to establish a reference database for selected haematological, biochemical and physiological parameters using apparently healthy Sprague-Dawley rats bred in the Animal House of Faculty of Medicine, University of Colombo(UCFM).Results: Differences in mean values of packed cell volume(PCV), mean corpuscular volume(MCV) and mean corpuscular hemoglobin concentration(MCHC), serum creatinine and blood glucose levels between the two genders were statistically significant. Lipid profile measurements did not differ significantly between genders, but mean and median values of triglycerides(TG) between male and female rats showed a difference of more than 10 mg/dL. The liver enzymes alkaline phosphatase(AP)and aspartate aminotransferase(AST) were also statistically significantly different between sexes. Despite wide variation in mean alanine aminotransferase(ALT)between sexes, the difference was not statistically significant.Conclusion: The findings of this project should support to a certain extent the"Reduction" aspect of the 3 Rs concept of Russell and Burch by reducing the number of Sprague-Dawley rats used in future research projects at UCFM.
文摘With his publication in 1873 [1] J. W. Gibbs formulated the thermodynamic theory. It describes almost all macroscopically observed properties of matter and could also describe all phenomena if only the free energy U - ST were explicitly known numerically. The thermodynamic uniqueness of the free energy obviously depends on that of the internal energy U and the entropy S, which in both cases Gibbs had been unable to specify. This uncertainty, lasting more than 100 years, was not eliminated either by Nernst’s hypothesis S = 0 at T = 0. This was not achieved till the advent of additional proof of the thermodynamic relation U = 0 at T = Tc. It is noteworthy that from purely thermodynamic consideration of intensive and extensive quantities it is possible to derive both Gibbs’s formulations of entropy and internal energy and their now established absolute reference values. Further proofs of the vanishing value of the internal energy at the critical point emanate from the fact that in the case of the saturated fluid both the internal energy and its phase-specific components can be represented as functions of the evaporation energy. Combining the differential expressions in Gibbs’s equation for the internal energy, d(μ/T)/d(1/T) and d(p/T)/d(1/T), to a new variable d(μ/T)/d(p/T) leads to a volume equation with the lower limit vc as boundary condition. By means of a variable transformation one obtains a functional equation for the sum of two dimensionless variables, each of them being related to an identical form of local interaction forces between fluid particles, but the different particle densities in the vapor and liquid spaces produce different interaction effects. The same functional equation also appears in another context relating to the internal energy. The solution of this equation can be given in analytic form and has been published [2] [3]. Using the solutions emerging in different sets of problems, one can calculate absolutely the internal energy as a function of temperature-dependent, phase-specific volumes and vapor pressure.
基金Supported by Major Project of the Co-construction Science and Technology Program between the Science and Technology Department of the National Administration of Traditional Chinese Medicine and the Zhejiang Administration of Traditional Chinese Medicine,No.GZY-ZJ-KJ-23040Zhejiang Medical and Health Science and Technology Project,No.2022497035+2 种基金Quzhou City Science and Technology Project,No.2022K75Zhejiang Chinese Medical University Scientific Research Fund Project,No.2021FSYYZZ09,No.2021FSYYZZ14The study was reviewed and approved by the Department of Orthopedics,The First Affiliated Hospital of Zhejiang Chinese Medical University(Zhejiang Provincial Hospital of Traditional Chinese Medicine)Institutional Review Board[Approval No.2023-K-162-01].
文摘BACKGROUND Gait is influenced by race,age,and diseases type.Reference values for gait are closely related to numerous health outcomes.To gain a comprehensive understanding of gait patterns,particularly in relation to race-related pathologies and disorders,it is crucial to establish reference values for gait in daily life considering sex and age.Therefore,our objective was to present sex and age-based reference values for gait in daily life,providing a valuable foundation for further research and clinical applications.AIM To establish reference values for lower extremity joint kinematics and kinetics during gait in asymptomatic adult women and men.METHODS Spatiotemporal,kinematics and kinetics parameters were measured in 171 healthy adults(70 males and 101 females)using the computer-aided soft tissue foot model.Full curve statistical parametric mapping was performed using independent and paired-samples t-tests.RESULTS Compared with females,males required more time(cycle time,double-limb support time,stance time,swing time,and stride time),and the differences were statistically significant.In addition,the step and stride lengths of males were longer.Compared to males,female cadence was faster,and statures-per-second and stride-per-minute were higher.There were no statistical differences in speed and stride width between the two groups.After adjusting for height,it was observed that women walked significantly faster than men,and they also had a higher cadence.However,in terms of step length,stride length,and stride width,both genders exhibited similarities.CONCLUSION We established reference values for gait speed and spatiotemporal gait parameters in Chinese university students.This contributes to a valuable database for gait assessment and evaluation of preventive or rehabilitative programs.
文摘Background: 1) To determine forced vital capacity (FVC) and forced expiratory volume in one second (FEV) for Beninese individuals of both sexes aged 17 - 20 years;2) Compare the observed values to those calculated based on the algorithms of the spirometer used. Materials and Methods: The FVC and FEV values were first measured using a Micro Quark spirometer and then calculated from equations for the European Respiratory Society-93 (ERS-93) in 148 subjects, including 46 girls. In each age group, the measured values for the height of the subjects were considered the only variables used to calculate the equations for FVC and FEV with their 95% confidence intervals. The means of the FEV and FVC values were obtained by univariate analysis. Results: The calculated FEV and FVC values were significantly higher (p Conclusion: The correction factors incorporated in spirometers imported from Europe no longer seem appropriate to measure the physical characteristics of African subjects. The differences between the two methods of assessment should be used as new ethnic correction factors.
基金Supported by Foundation of the Chinese Medical Association (07010280036)
文摘Objective To evaluate the validity of current spirometric reference values for healthy adults in Shanghai.Methods Healthy non-smoking adults without respiratory diseases were randomly enrolled in the study.Gender,age,standing height,body weight and spirometric parameters were obtained.The parameters were compared with reference values from current prediction equations with or without conversion factors.Results A total of 127 healthy adults (60 males and 67 females) aged 18-57 years participated in the study.In the study,pulmonary function parameters of healthy adults,especially of female adults were higher than predicted values,according to prediction equations from Chinese subjects in Shanghai.There were discrepancies between measuring values and reference values from foreign prediction equations with or without conversion factors.Conclusion Spirometric parameters of healthy adults,especially female population in Shanghai might be underestimated by present reference values from Chinese subjects.Foreign reference values and their conversion factors are not able to match measuring values.Validity of spirometric reference values for adults in Shanghai should be reassessed.
文摘随着我国轨道交通网络飞速扩张,其巨大运营能耗,尤其是照明系统能耗,成为运营成本控制的重点。为实现绿色、低碳、高效的运营目标,智能照明控制技术的研究与应用至关重要。本文重点探讨基于电力载波通信(Power Line Communication,PLC)技术的照明智控系统在轨道交通领域的节能应用。首先,分析轨道交通站点照明系统的特点与能耗现状,深入阐述PLC技术的基本原理及其相较其他技术的全方位优势,特别是在施工简便性、材料节省、运维管理智能化方面的突出价值。其次,设计出一套适用于地铁站站厅、站台等场景的基于PLC的照明智控系统架构,详细介绍其硬件组成、通信协议和智能控制策略(包括分区控制、定时控制、光感联动及人流感应控制)。最后,通过在温州轨道交通某站点试点案例分析,对比系统改造前后的能耗数据,证明该系统在显著降低照明能耗(平均节能率超30%)、节约改造材料与施工成本、实现运维管理数字化方面的卓越性,为PLC技术在轨道交通节能领域的规模化推广提供强有力的理论依据和实践参考。
基金National Natural Science Foundation of China No.49771007 No.40141002
文摘A research is conducted on the relationship between the normal reference value of 20,475 examples of hemoglobin of young women and five geographical factors in 208 areas in China, the normal reference value is determined by the hemoglobincyanide method. It is found that the correlation of geographical factors and the normal reference value of hemoglobin of young women are quite significant (F=142.81). By using the method of multiple linear regression analysis, one regression equation is inferred. If geographical values are obtained in some areas, the normal reference value of hemoglobin of young women of this area can be reckoned by using the regression equation. Furthermore, depending on the geographical factors, China can be divided into six regions: Qinghai-Tibet (Qingzang) Plateau, Southwest, Northwest, Southeast, North and Northeast China.
文摘AIM To describe the thromboelastography(TEG) "reference" values within a population of liver transplant(LT) candidates that underline the differences from healthy patients.METHODS Between 2000 and 2013, 261 liver transplant patients with a model for end-stage liver disease(MELD) score between 15 and 40 were studied. In particular the adult patients(aged 18-70 years) underwent to a first LT with a MELD score between 15 and 40 were included, while all patients with acute liver failure, congenital bleeding disorders, and anticoagulant and/or antiplatelet drug use were excluded. In this population of cirrhotic patients, preoperative haematological and coagulation laboratory tests were collected, and the pretransplant thromboelastographic parameters were studied and compared with the parameters measured in a previously studied population of 40 healthy subjects. The basal TEG parameters analysed in the cirrhotic population of liver candidates were as follows: Reaction time(r), coagulation time(k), Angle-Rate of polymerization of clot(α Angle), Maximum strenght of clot(MA), Amplitudes of the TEG tracing at 30 min and 60 min after MA is measured(A30 and A60), and Fibrinolysis at 30 and 60 min after MA(Ly30 and Ly60). The possible correlation between the distribution of the reference range and the gender, age, MELD score(higher or lower than 20) and indications for transplantation(liver pathology) were also investigated. In particular, a MELD cut-off value of 20 was chosen to verify the possible correlation between the thromboelastographic reference range and MELD score. RESULTS Most of the TEG reference values from patients with end-stage liver disease were significantly different from those measured in the healthy population and were outside the suggested normal ranges in up to 79.3% of subjects. Wide differences were found among all TEG variables, including r(41.5% of the values), k(48.6%), α(43.7%), MA(79.3%), A30(74.4%) and A60(80.9%), indicating a prevailing trend to hypocoagulability. The differences between the mean TEG values obtained from healthy subjects and the cirrhotic population were statistically significant for r(P = 0.039), k(P < 0.001), MA(P < 0.001), A30(P < 0.001), A60(P < 0.001) and Ly60(P = 0.038), indicating slower and less stable clot formation in the cirrhotic patients. In the cirrhotic population, 9.5% of patients had an r value shorter than normal, indicating a tendency for faster clot formation. Within the cirrhotic patient population, gender, age and the presence of hepatocellular carcinoma or alcoholic cirrhosis were not significantly associated with greater clot firmness or enhanced whole blood clot formation, whereas greater clot strength was associated with a MELD score < 20, hepatitis C virus and cholestaticrelated cirrhosis(P < 0.001; P = 0.013; P < 0.001).CONCLUSION The range and distribution of TEG values in cirrhotic patients differ from those of healthy subjects, suggesting that a specific thromboelastographic reference range is required for liver transplant candidates.
