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The effects of complexing conditions on the formation of amylose-lipid-protein complexes and relationships between structure and digestion of amylose-lipid and amylose-lipid-protein complexes were poorly understood. The objective of this study was to investigate the effects of complexing time (0, 0.5, 2, 4 and 6 h) and temperature (60, 70, 80, 90 and 100 °C) on the structure and in vitro amylolysis of amylose-lauric acid (AM-LA) and amylose-lauric acid-ß-lactoglobulin (AM-LA-ßLG) complexes, and to understand the relationships between structure and in vitro digestiblity of these complexes. Longer complexing time and higher complexing temperature promoted the formation of greater amounts of the more stable type II crystallites than type I crystallites in both AM-LA and AM-LA-ßLG complexes, which in turn decreased the rate and extent of the complexes digestion to a greater extent. Correlation analyses between parameters for structure and digestion kinetics showed that both the quantity of AM-LA and AM-LA-ßLG complexes and the quality of their arrangement into V-type crystallites influenced their rate and extent of digestion. This study demonstrates that AM-LA and AM-LA-ßLG complexes can be prepared with designed structural and functional properties tailored for various applications.
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Amilosa , Lactoglobulinas , Amilosa/química , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Ácidos Láuricos/química , Temperatura , Cinética , Digestión , HidrólisisRESUMEN
Soil extractable nitrate, ammonium, and organic nitrogen (N) are essential N sources supporting primary productivity and regulating species composition of terrestrial plants. However, it remains unclear how plants utilize these N sources and how surface-earth environments regulate plant N utilization. Here, we establish a framework to analyze observational data of natural N isotopes in plants and soils globally, we quantify fractional contributions of soil nitrate (fNO3-), ammonium (fNH4+), and organic N (fEON) to plant-used N in soils. We find that mean annual temperature (MAT), not mean annual precipitation or atmospheric N deposition, regulates global variations of fNO3-, fNH4+, and fEON. The fNO3- increases with MAT, reaching 46% at 28.5 °C. The fNH4+ also increases with MAT, achieving a maximum of 46% at 14.4 °C, showing a decline as temperatures further increase. Meanwhile, the fEON gradually decreases with MAT, stabilizing at about 20% when the MAT exceeds 15 °C. These results clarify global plant N-use patterns and reveal temperature rather than human N loading as a key regulator, which should be considered in evaluating influences of global changes on terrestrial ecosystems.
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Ecosistema , Nitratos , Nitrógeno , Plantas , Suelo , Temperatura , Suelo/química , Nitrógeno/metabolismo , Nitrógeno/análisis , Plantas/metabolismo , Nitratos/metabolismo , Nitratos/análisis , Compuestos de Amonio/metabolismo , Compuestos de Amonio/análisis , Isótopos de Nitrógeno/análisis , Isótopos de Nitrógeno/metabolismoRESUMEN
The whopping increase in solid waste landfills poses serious threats to the environment. Compared to the drilling method, geophysical methods are effective, non-invasive techniques for delineating the contaminant distribution. In this study, electrical resistivity tomography (ERT) and induced polarization (IP) were used to investigate a solid waste deposit. The results of ERT/IP imaging illustrate the potential of the method in environmental studies. Based on the results of 21 survey lines, geo-electrical signals can be summarized as three types: with only high resistivity for construction & demolition wastes (CDWs) areas (RO type), contaminated soil for high chargeability (CO type), and contaminants under CDWs layer have both high resistivity and chargeability (RC type). Chargeability values over 10.2 mV/V correspond to contaminated soil with an overall concentration larger than 75 mg/kg. With the three-dimensional interpolation results and the determined chargeability criteria, the total volume of contaminated soil is 40,555 cubic meters. Finally, comparing the efficiency, cost and results of IP and drilling sampling methods shows that the IP is an efficient, low-cost and high-resolution contamination characterization. The results support that ERT/IP information can fulfill rapid and initial identification as a reliable tool in engineering and environmental investigations.
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Residuos Sólidos , Residuos Sólidos/análisis , Tomografía/métodos , Eliminación de Residuos/métodos , Suelo/química , Monitoreo del Ambiente/métodosRESUMEN
Ranula is a mucous cyst that occurs in the sublingual gland (SLG) in the floor of the mouth. It can be classified into two types based on origins: One is the the lesser sublingual gland (LSLG) in the anterior segment and the Rivini duct, which is connected to it, and the other is the greater sublingual gland (GSLG) in the posterior segment. Because of the anatomical characteristics, surgical resection of the cysts carries the risk of damaging adjacent tissues and has a high recurrence rate. Intralesional injection of sclerotherapy may be a better alternative treatment. We summarized 65 cases of ranula treated with intralesional injections of bleomycin(BML). According to the origin of the ranula, 60 cases were from the LSLG and the Rivini duct, and 5 cases were from the GSLG. The results showed that 60 cases of ranula from LSLG and Rivini ducts were 100% cured during the follow-up period. The median number of injections for all patients was 1.16. All 5 cases of ranula from the GSLG did not wholly recover. This study confirmed that BLM intralesional injection is a safe and effective treatment modality for cysts from LSLG or the ducts of Rivini rather than GSLG. Therefore, before treatment, it is necessary to determine the type and origin of the cyst by characterizing its morphology to ensure the effectiveness of the treatment.
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Bleomicina , Inyecciones Intralesiones , Ránula , Escleroterapia , Bleomicina/administración & dosificación , Bleomicina/uso terapéutico , Humanos , Escleroterapia/métodos , Femenino , Adulto , Masculino , Persona de Mediana Edad , Adolescente , Soluciones Esclerosantes/uso terapéutico , Soluciones Esclerosantes/administración & dosificación , Adulto Joven , Resultado del Tratamiento , Anciano , Niño , Glándula SublingualRESUMEN
Our objective was to evaluate the topographic and surgical factors of early myopic regression between laser in situ keratomileusis (LASIK) and small-incision lenticule extraction (SMILE). A retrospective case-control study was conducted, and 368 and 92 eyes were enrolled in the LASIK and SMILE groups via propensity score matching (PSM). Visual acuity, refractive status, axial length, and topographic/surgical parameters were collected. Multiple linear regression was applied to the yield coefficient and the 95% confidence interval (CI) of the parameters. The cumulative incidence of early myopic regression was higher in the LASIK group (p < 0.001). In the SMILE group, a lower central corneal thickness (CCT) thinnest value and a higher corneal cylinder associated with early myopic regression were observed; meanwhile, in the LASIK group, a lower CCT thinnest value, a higher steep corneal curvature, a larger optic zone, and a lower flap thickness related to early myopic regression were observed (all p < 0.05). In the SMILE group, a higher CCT difference correlated with early myopic regression was observed compared to the LASIK group (p = 0.030), and higher steep corneal curvature and lower cap/flap thickness (both p < 0.05) correlated with early myopic regression were observed in the LASIK group compared to the SMILE group. In conclusion, CCT differences significantly influence early myopic regression in the SMILE group; meanwhile, corneal curvature and flap thickness affect early myopic regression principally in the LASIK group.
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Structural factors that determine the amylolysis of starch-lipid complexes have remained unclear. Understanding the relationship between the structure and amylolysis of starch-lipid complexes is important for the design and preparation of complexes with predictable digestibility. In this study, the multiscale structures and amylolytic properties of complexes formed under different conditions between debranched high-amylose starch (DHAMS) and lauric, myristic, palmitic, and stearic acids were investigated. Higher complexing temperatures facilitated the formation of DHAMS-fatty acid (FA) complexes, especially the more stable type II crystallites. Longer complexing times also promoted the formation of complexes and the type II crystallites, except for DHAMS-lauric acid (LA). Molecular dynamics simulations showed that the binding free energy for the formation of DHAMS-LA complexes (10 kJ/mol) was lower than those for the other three DHAMS-FA complexes (20-50 kJ/mol), accounting for the lower stability of DHAMS-LA complexes at longer complexing times. The rate and extent of enzymatic digestion of the DHAMS-FA complexes were much lower in comparison to those of gelatinized HAMS. Correlation analyses showed that the rate and extent of enzymic digestion of DHAMS-FA complexes were mainly determined by the degree of crystallite perfection of the complexes.
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We sought to evaluate the topographic risk factors for early myopic regression after small-incision lenticule extraction (SMILE). A retrospective caseâcontrol study was conducted, and individuals who underwent SMILE surgery were enrolled. Among them, 406 and 14 eyes were categorized into the nonregression and regression groups, respectively. The preoperative and postoperative parameters in the two groups were collected, including spherical refraction (SE), axial length (AXL) and topographic data. A generalized linear model was adopted to analyze the difference in each parameter between the two groups. After 6 months, UCVA decreased in the regression group, and SE increased in the regression group (both P < 0.05). The increase in the CCT at the thinnest point (P = 0.044), flat corneal curvature (P = 0.012) and TCRP (P = 0.001) were significantly greater in the regression group. Regarding the risk factors for myopic regression, preoperative SE, preoperative sphere power, preoperative AXL, preoperative flat corneal curvature, preoperative SA, early postoperative SE, early postoperative sphere power, early postoperative AXL and early postoperative CCT difference were significantly greater in the regression group (all P < 0.05). The SE, sphere power, AXL, preoperative flat corneal curvature, preoperative SA, and postoperative CCT difference correlate with early myopic regression after SMILE.
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Cirugía Laser de Córnea , Miopía , Herida Quirúrgica , Humanos , Córnea/cirugía , Sustancia Propia/cirugía , Agudeza Visual , Estudios Retrospectivos , Estudios de Casos y Controles , Cirugía Laser de Córnea/efectos adversos , Láseres de Excímeros/uso terapéutico , Refracción Ocular , Miopía/cirugía , Herida Quirúrgica/cirugíaAsunto(s)
Hiperglucemia , Resistencia a la Insulina , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Humanos , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Resistencia a la Insulina/genética , Hiperglucemia/tratamiento farmacológico , Femenino , Masculino , Adulto , Transportador 2 de Sodio-Glucosa/genética , Transportador 2 de Sodio-Glucosa/metabolismoRESUMEN
Photocatalytic technology is a popular research area for converting solar energy into environmentally friendly chemicals and is considered the greenest approach for producing H2O2. However, the corresponding reactive oxygen species (ROS) and pathway involved in the photocatalytic generation of H2O2 by the Bi2.15WO6-glucose system are still not clear. Quenching experiments have established that neither â¢OH nor h+ contribute to the formation of H2O2, and show that the formed surface superoxo (≡Bi-OOâ¢) and peroxo (≡Bi-OOH) species are the predominant ROS in H2O2 generation. In addition, various characterizations indicate the enhanced electron-transfer on the surface of Bi2.15WO6 with increasing contents of glucose via the ligand-to-metal charge transfer pathway, confirming H-transfer from glucose to ≡Bi-OO⢠or ≡Bi-OOH. The increased production of H2O2 with decreasing bond dissociation energy (BDEO-H) values of various phenolic compounds again supports the H-transfer mechanism from phenolic compounds to ≡Bi-OO⢠and then to ≡Bi-OOH. DFT calculations further reveal that on the Bi2.15WO6 surface, oxygen is sequentially reduced to ≡Bi-OO⢠and ≡Bi-OOH, while H-transfer from H2O or glucose to ≡Bi-OO⢠and ≡Bi-OOH, resulting in the production of H2O2. The lower energy barrier of H-transfer from adsorbed glucose (0.636 eV) than that from H2O (1.157 eV) indicates that H-transfer is more favorable from adsorbed glucose. This work gives new insight into the photocatalytic generation of H2O2 by Bi2.15WO6 in the presence of glucose/phenolic compounds via the H-abstraction pathway.
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The effects of endogenous lipids and protein in sorghum flour on starch digestion were studied following the depletion of lipids and/or protein and after the reconstitution of separated fractions. The removal of protein or lipids moderately increases the digestibility of starch in raw (uncooked) sorghum flour to values close to those for purified starch. Rapid Visco Analyzer data (as a model for the cooking process) show that cooked sorghum flours with lipids have a lower starch digestibility than those without lipids after RVA processing, due to the formation of starch-lipid complexes as evidenced by their higher final viscosity and larger enthalpy changes. Additionally, the formation of a starch-lipid-protein ternary complex was identified in cooked sorghum flour, rather than in a reconstituted ternary mixture, according to the unique cooling stage viscosity peak and a greater enthalpy of lipid complexes. After heating, the sorghum flour showed a lower digestibility than the depleted flours and the reconstituted flours. The results indicate that the natural organization of components in sorghum flour is an important factor in facilitating the interactions between starch, lipids, and protein during RVA processing and, in turn, reducing the starch digestion.
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A quantitative method was developed to characterize the short-range order in non-crystalline starch by Raman spectroscopy. The Raman spectra of three forms of non-crystalline starches (just-gelatinized starch, which was heated to the point of having just lost its long-range order but still retaining essentially all of its short-range order, gelatinized starch and amorphous starch) were resolved into subspectra to calculate the short-range ordered phases. By deducting the spectra of amorphous starch using a subtraction technique, the areas of subspectra for short-range ordered phases in just-gelatinized and gelatinized starches were obtained. The ratio of the area for short-range ordered phases in gelatinized starch relative to that in just-gelatinized starch was negatively correlated with water content for gelatinization. Based on this, we propose that this ratio of areas provides a quantitative measure for assessing the short-range order in non-crystalline starch. This study provides an alternative and simpler method to an X-ray diffraction protocol proposed previously.
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A model system of gelatinized wheat starch (GWS) and lauric acid (LA) was used to examine the effect of residual short-range molecular order in GWS on the formation of starch-lipid complexes. The extent of residual short-range molecular order, as determined by Raman spectroscopy, decreased with increasing water content or heating duration of gelatinization. The enthalpy changes, crystallinity, short-range molecular order and the in vitro enzymic digestion of GWS-LA complexes increased initially to a maximum and then declined as the short-range molecular order in GWS decreased, showing that there was an optimal amount of residual short-range molecular order in GWS for maximizing GWS-LA complexes formation. Below this optimum amount, the limited disruption of short-range molecular order may constrain the mobility of amylose chains for complexation with LA, whereas with excessive disruption above this amount the amylose chains may be too disorganized or entangled to form complexes with LA. The susceptibility of GWS-LA complexes to enzymatic hydrolysis was influenced by both long- and short-range structural order, and to a lesser extent the amounts of complexes. This study showed clearly the role of short-range molecular order in gelatinized starch in influencing the formation of GWS-LA complexes.
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Amilosa , Almidón , Almidón/química , Amilosa/química , Ácidos Láuricos/química , HidrólisisRESUMEN
Knowledge about the prebiotic characteristics of cellulose by in vitro fermentation is not complete due to the neglect of small intestinal fermentation. This study investigated the effects of small intestinal fermentation on the prebiotic characteristics of cellulose in the large intestine and potential mechanisms through an approach of combined in vivo small intestinal fermentation and in vitro fermentation. The structural similarity between cellulose in feces and after processing by the approach of this study confirmed the validity of the approach employed. Results showed that small intestinal fermentation of cellulose increased both acetate and propionate content and enriched Corynebacterium selectively. Compared to in vitro fermentation after in vitro digestion of cellulose, the in vitro fermentation of cellulose after in vivo small intestinal fermentation produced higher contents of acetate and propionate as well as the abundance of probiotics like Ruminococcaceae_UCG-002, Blautia, and Bifidobaterium. The changes in the structural features of cellulose after in vivo small intestinal fermentation were more obvious than those after in vitro digestion, which may account for the greater production of short-chain fatty acids (SCFAs) and the abundance of probiotics. In summary, small intestinal fermentation enhanced the prebiotic characteristics of cellulose in the large intestine by predisrupting its structure.
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Celulosa , Prebióticos , Celulosa/metabolismo , Prebióticos/análisis , Propionatos/metabolismo , Fermentación , Intestino Grueso/metabolismo , Ácidos Grasos Volátiles/metabolismo , Acetatos/metabolismo , Heces/microbiología , DigestiónRESUMEN
BACKGROUND: To evaluate the possible topographic and surgical risk factors for high postoperative residual astigmatism in patients who undergo small-incision lenticule extraction (SMILE) surgery and have different myopia degrees. METHODS: A retrospective cohort study was conducted, and patients who underwent SMILE surgery were enrolled. A total of 80 and 150 eyes from 40 to 75 individuals, respectively, were selected as the low myopia and high myopia groups. The demographic data, visual acuity, refraction, topographic parameters and surgical settings were recorded. Multiple linear regression with interaction tests were performed to survey the risk factors for high postoperative residual astigmatism in each group. RESULTS: Five (6.25%) and 9 (6.00%) eyes presented with high postoperative residual astigmatism in the low myopia and high myopia groups, respectively, but these differences were not significant (P = 0.569). A steep corneal curvature was correlated with a greater risk of high postoperative residual astigmatism in the low myopia group (P = 0.015), while a higher degree of cycloplegic cylinder power, steeper corneal curvature, greater topographic cylinder power, smaller optic zone and longer incision length were associated with a high rate of postoperative residual astigmatism in the high myopia group (all P < 0.05). In addition, the interaction effects of cycloplegic and topographic cylinder power and longer incision length on the incidence of high postoperative residual astigmatism development were more evident in the high myopia group than in the low myopia group (all P < 0.05). CONCLUSIONS: A steep corneal curvature correlates with a high risk of high postoperative residual astigmatism after SMILE surgery, and a higher degree of cycloplegic and topographic cylinder and longer incision are associated with high postoperative residual astigmatism in individuals with high myopia.
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Astigmatismo , Cirugía Laser de Córnea , Miopía , Humanos , Astigmatismo/etiología , Astigmatismo/cirugía , Estudios Retrospectivos , Midriáticos , Topografía de la Córnea , Microcirugia , Refracción Ocular , Miopía/cirugía , Córnea/cirugía , Sustancia Propia/cirugía , Láseres de Excímeros/uso terapéuticoRESUMEN
AIM OF THE REVIEW: The primary aim of this systematic review was to investigate the most common electroencephalogram (EEG)-based machine learning (ML) model with the highest Area Under Receiver Operating Characteristic Curve (AUC) in two ML categories, conventional ML and Deep Neural Network (DNN), to predict the neurologic outcomes after cardiac arrest; the secondary aim was to investigate common EEG features applied to ML models. METHODS: Systematic search of medical literature from PubMed and engineering literature from Compendex up to June 2, 2023. One reviewer screened studies that used EEG-based ML models to predict the neurologic outcomes after cardiac arrest. Four reviewers validated that the studies met selection criteria. Nine variables were manually extracted. The top-five common EEG features were calculated. We evaluated each study's risk of bias using the Quality in Prognosis Studies guideline. RESULTS: Out of 351 identified studies, 17 studies met the inclusion criteria. Random Forest (RF) (n = 7) was the most common ML model in the conventional ML category (n = 11), followed by Convolutional Neural Network (CNN) (n = 4) in the DNN category (n = 6). The AUCs for RF ranged between 0.8 and 0.97, while CNN had AUCs between 0.7 and 0.92. The top-three commonly used EEG features were band power (n = 12), Shannon's Entropy (n = 11), burst-suppression ratio (n = 9). CONCLUSIONS: RF and CNN were the two most common ML models with the highest AUCs for predicting the neurologic outcomes after cardiac arrest. Using a multimodal model that combines EEG features and electronic health record data may further improve prognostic performance.
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Paro Cardíaco , Humanos , Paro Cardíaco/terapia , Paro Cardíaco/complicaciones , Aprendizaje Automático , Pronóstico , Electroencefalografía , Curva ROCRESUMEN
Objective:To explore the mechanism of Mito-TEMPO inhibiting the activation of BV2 microglia induced by lead(Pb)exposure.Methods:Mouse microglia BV2 were cultured in vitro.The effects of different concentrations of lead exposure on the viability of BV2 cells were determined by MTT colorimetric method,and a model of lead expo-sure was developed and intervened with Mito-TEMPO antioxidant.Immunofluorescence staining was used to detect the expression of M1 activation marker CD86 protein.Enzyme-linked immunosorbent assay was used to detect the expression of pro-inflammatory factors interleukin-1 β(IL-1β),tumor necrosis factor α(TNF-α),interleukin-6(IL-6).Mito-chondrial superoxide indicator(MitoSOX)staining was used to detect the level of mitochondrial oxidative stress.JC-1 staining was used to detect mitochondrial membrane potential.The respiratory ability of mitochondria was detected by cell energy metabolism analysis system(O2k).Results:Compared with the control group,the expression of CD86 protein,the levels of pro-inflammatory cytokines IL-1β,TNF-α and IL-6 in BV2 cells increased significantly,the level of oxidative stress in mitochondria increased significantly,and the mitochondrial membrane potential and respiratory ability decreased significantly in lead exposed group.Mito-TEMPO treatment significantly reduced the oxidative stress and functional damage of mitochondria in BV2 cells,and significantly inhibited the M1 activation level of BV2 cells.Conclusion:The results show that Mito-TEMPO treatment can reverse the M1 activation of BV2 cells induced by lead exposure,and the specific mechanism may be related to the reduction of mitochondrial oxidative stress and dysfunction by Mito-TEMPO.
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Objective To summarize the multi slice spiral computed tomography(MSCT)features of bronchiolar adenoma(BA).Methods The imaging data of 9 cases of BA confirmed by surgery and pathology were analyzed retrospectively,and relevant literature was also reviewed.Results Among the 9 cases of BA,there were 8 cases with peripheral BA(away from the pleura≤5 mm)inclu-ding 4 cases close to the pleura and 1 case in central area.BA were located in the superior lobe of the right lung in 3 cases,the middle lobe of the right lung in 2,the inferior lobe of the right lung in 2,and the inferior lobe of the left lung in 2.Five cases were solid nod-ules,2 were ground-glass nodules and other 2 were cystic cavity nodules.In 2 cases of the solid nodules,the boundary on the non-venous side was blurred.In the 1 case of the ground-glass nodule,linear and reticular shadows were observed in the lesion,accompanied by a blurred boundary.2 nodules had mild pleura indentation,and other 7 nodules were found blood vessels entering into or adhering to the lesion,3 of which were accompanied by vascular thickening.In 8 cases with 2-48 month followed up,1 cystic cavity nodule was accompa-nied by obstructive pneumonia and then inflammatory absorption,1 solid nodule enlarged accompanied by the appearance of vacuoles,and the rest 6 had no changes.One central type nodule was operated after the CT examination.Conclusion BA are mainly manifes-ted as peripheral nodules of the lung,mostly close to the pleura and away from the pleura≤5 mm.Most BA are solid nodules,and sometimes are ground-glass or cystic cavity nodules.Some nodules show blurred boundaries or inflammation on the non-venous side,and few nodules increase during follow-up,with or without small vacuoles.
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[Objective]To explore the connotation of neo-Confucianism in ZHU Danxi medicine.[Methods]Combining the research methods of medicine and philosophy,based on ZHU Danxi's medical writings and related knowledge of neo-Confucianism,the connotation of neo-Confucianism of Danxi medicine was discussed from three aspects:"cognition view""sports view""cultivation view".[Results]ZHU Danxi was influenced by the thought of"one principle and different justics"and regarded medicine as the way to practice Confucian ideal.Using the understanding method of"thinking phyics",ZHU Danxi put forward some important medical theories such as"the theory of excess of Yang and deficiency of Yin"and"the theory of fire".Based on the concept of"movement was the heart of heaven and earth",the important significance of Qi movement and constant movement of"Xiang fire"to human life was realized.Based on the sports concept of"extreme things must be reversed"and"the gentleman should be careful to move",the author realized the great harm to the human body caused by the rash movement of"fire"and advocated the idea of"careful movement"for health preservation.Based on the cultivation view of"heart regulating temperament",the author put forward"king fire mastering prime minister fire",emphasized the active role of"heart"of"king fire",cultivated the"nature"of morality,controlled the"emotion"of desire,and maintained the constant movement of"corresponding fire"and supplemented life.Applying the cultivation view of"mastering static without desire"to health but disease required that through tempering appetite and lust,people's natural desires conformed to the Confucian"reason",in order to be no severely ill and spend the whole life.[Conclusion]ZHU Danxi's medical science is rich in connotation,which is a powerful witness of the influence of the reform of Confucianism on medical innovation in Song and Yuan Dynasties.On the one hand,Danxi's"aid theory into medicine"built a strong support for medical innovation,and made his medical theory rise to the height of"heaven theory",so that he was convinced in the Jinyuan period of medical contention;On the other hand,it also demonstrated the all-encompassing universality and supreme authority of"heavenly principles"as cosmic laws.
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BACKGROUND:Confirming the reliability and validity of the My jump 2 application for measuring lower limb vertical stiffness may offer the possibility of it as an alternative to the Kistler three-dimensional force platform for measuring lower limb stiffness. OBJECTIVE:To verify the reliability and validity of the My Jump 2 application in measuring lower limb vertical stiffness of college students. METHODS:The drop jump data of the participants were collected through the Kistler three-dimensional force platform and the My Jump 2 application,and the vertical stiffness of the participants'lower limb vertical stiffness was calculated.The intraclass correlation coefficient was used to analyze the data measured by the My Jump 2 application and the Kistler three-dimensional force platform,attempting to verify the reliability of the My Jump 2 application.The bias and average between the two devices were drawn into a Bland-Altman diagram to verify the consistency between the two test methods.Finally,the test-retest reliability of the My Jump 2 applications at 30 cm and 40 cm was analyzed using the Cronbach's alpha(α)and coefficient of variation.Pearson product-moment correlation was used to analyze the correlation of My Jump 2 applications. RESULTS AND CONCLUSION:My Jump 2 application has high reliability and validity when measuring the vertical stiffness of the lower limb.At the same time,due to its advantages of low cost,convenient portability and field testing for large samples,it can be used as an alternative to the Kistler three-dimensional force platform to test the vertical stiffness of the lower limb in college students and similar populations.