Edema is a common pathological symptom, but its development mechanism is unknown. Based on the bearings of pressure upon interstitium structure and substantial exchange between plasma and interstitial fluid, a dymamics model describing the development of edema was set up. The model's theoretical results showed that the variations of interstitium pressure and structure due to imbalance of substantial exchange may lead to the development of edema, which is in accordance with recent clinical researches. Discussions on the dynamic mechanism of the development of edema proposed that the best way to prevent edema is instituting treatment before the interstitial structure being destroyed.
Edema ; physiopathology ; Humans ; Models, Biological ; Nonlinear Dynamics

The aim of this study was to produce a simple and inexpensive technique for estimating the obturator foramen area (OFA) from young calves based on the hypothesis that OFA can be extrapolated from simple linear measurements. Three linear measurements - dorsoventral height, craneocaudal width and total perimeter of obturator foramen - were obtained from 55 bovine hemicoxae. Different algorithms for determining OFA were then produced with a regression analysis (curve fitting) and statistical analysis software. The most simple equation was OFA (mm2) = [3,150.538 + (36.111*CW)] - [147,856.033/DH] (where CW = craneocaudal width and DH = dorsoventral height, both in mm), representing a good nonlinear model with a standard deviation of error for the estimate of 232.44 and a coefficient of multiple determination of 0.846. This formula may be helpful as a repeatable and easily performed estimation of the obturator foramen area in young bovines. The area of the obturator foramen magnum can thus be estimated using this regression formula.
Biometry ; Foramen Magnum ; Nonlinear Dynamics ; Osteology

A new mathematical equation characterizing the compression of pharmaceutical materials is presented. This equation presumed that the rate of change of the compressible volume of powder with respect to the pressure is proportional to the compressible volume. The new model provided a good fit to several model substances employing non-linear regression techniques. The validity of the model had been verified with experimental results of various pharmaceutical powders according to the Akaikes informatics criterion (AIC) and the sum of squared deviations (SS). The parameter of the new model might reflect quantitatively the fundamental compression behaviors of the powders. It had demonstrated that the proposed model could well predict the compaction characteristics of solid particles like the Kawakita model.
Compressive Strength ; Nonlinear Dynamics ; Powders ; chemistry ; Pressure

A modelling scheme for the stress analysis taking into account load transfer characteristics of the osseointegrated interfaces between dental implant and surrounding alveolar bone was investigated. Main aim was to develop a more realistic simulation methodology for the load transfer at the interfaces than the prefect bonding assumption at the interfaces which might end up the reduced level in the stress result. In the present study, characteristics of osseointegrated bone/implant interfaces was modelled with material nonlinearity assumption. Bones at the interface were given different stiffness properties as functions of stresses. Six different models, i.e. tens0, tens20, tens40, tens60, tens80, and tens100 of which the tensile moduli of the bones forming the bone/implant interfaces were specified from 0, 20, 40, 60, 80, and 100 percents, respectively, of the compressive modulus were analysed. Comparisons between each model were made to study the effect of the tensile load carrying abilities, i.e. the effectivity of load transfer, of interfacial bones on the stress distribution. Results of the present study showed significant differences in the bone stresses across the interfaces. The peak stresses, however, were virtually the same regardless of the difference in the effectivity of load transfer, indicating the conventional linear modelling scheme which assumes perfect bonding at the bone/implant interface can be used without causing significant errors in the stress levels.
Dental Implants* ; Lifting ; Linear Models ; Nonlinear Dynamics*

The use of non-invasive blood glucose detection techniques can help diabetic patients to alleviate the pain of intrusive detection, reduce the cost of detection, and achieve real-time monitoring and effective control of blood glucose. Given the existing limitations of the minimally invasive or invasive blood glucose detection methods, such as low detection accuracy, high cost and complex operation, and the laser source's wavelength and cost, this paper, based on the non-invasive blood glucose detector developed by the research group, designs a non-invasive blood glucose detection method. It is founded on dual-wavelength near-infrared light diffuse reflection by using the 1 550 nm near-infrared light as measuring light to collect blood glucose information and the 1 310 nm near-infrared light as reference light to remove the effects of water molecules in the blood. Fourteen volunteers were recruited for
Blood Glucose ; Diabetes Mellitus ; Humans ; Nonlinear Dynamics

OBJECTIVES: Load carrying tasks are recognized as one of the primary occupational factors leading to slip and fall injuries. Nevertheless, the mechanisms associated with load carrying and walking stability remain illusive. The objective of the current study was to apply local dynamic stability measure in walking while carrying a load, and to investigate the possible adaptive gait stability changes. METHODS: Current study involved 25 young adults in a biomechanics research laboratory. One tri-axial accelerometer was used to measure three-dimensional low back acceleration during continuous treadmill walking. Local dynamic stability was quantified by the maximum Lyapunov exponent (maxLE) from a nonlinear dynamics approach. RESULTS: Long term maxLE was found to be significant higher under load condition than no-load condition in all three reference axes, indicating the declined local dynamic stability associated with load carrying. CONCLUSION: Current study confirmed the sensitivity of local dynamic stability measure in load carrying situation. It was concluded that load carrying tasks were associated with declined local dynamic stability, which may result in increased risk of fall accident. This finding has implications in preventing fall accidents associated with occupational load carrying.
Acceleration ; Biomechanics ; Gait ; Humans ; Lifting ; Nonlinear Dynamics ; Walking ; Young Adult

OBJECTIVETo study the characteristics of the effect of different temperatures on mortality of different cities through analyzing the relationship between mortality and meteorology of five Chinese cities.

METHODSWe get the demography and climate data of Beijing, Tianjin, Shanghai, Nanjing and Changsha cities from National Center of Disease Control and Prevention and Climate net respectively. Then we applied the R software and Distributed Lag Non-linear Models (DLNM) package to analyze our data and find the nonlinear and lag effects on mortality using DLNM.

RESULTSThe city of Beijing and Tianjin are located in the temperate zone. And the climate of Shanghai, Nanjing, Changsha belong to subtropical monsoon climate. When the daily mean temperature arrived 30°C and on lag 0 day, the values of relative risk of effect of high mean temperature on mortality in Nanjing (1.31, 95%CI: 1.21 - 1.41) and Changsha (1.25, 95%CI: 1.13 - 1.39) are larger than that in Beijing (1.18, 95%CI: 1.12 - 1.25), Tianjin (1.18, 95%CI: 1.10 - 1.26) and Shanghai(1.15, 95%CI: 1.06 - 1.24). While the relative risk of effect of low mean temperature on mortality is lower and lasts for a longer lag time. During the whole lag time, the relative risk of effect of the lowest daily mean temperature of each city on mortality in Tianjin, Changsha, Beijing, Nanjing, and Shanghai is 3.41, 95%CI: 1.60 - 7.27, 2.15, 95%CI: 1.11 - 4.15, 2.24, 95%CI: 1.12 - 4.48, 2.80, 95%CI: 1.75 - 4.48, 1.53, 95%CI: 1.12 - 2.03, respectively. The cumulative effect of mean temperature on mortality appears like a U-shape. When on lag 0-1 day, the value of relative risk of effect of extremely high temperature and the highest mean temperature on mortality is larger than 1. While the effect of low temperature on mortality becomes obvious after lag 2 days.

CONCLUSIONDepending on this research, extremely low temperature and the lowest mean temperature has a more obvious impact on mortality in the northern area than in the south. Extremely high temperature and the highest daily mean temperature is on the contrary. Meanwhile, different temperatures have different impacts on mortality in the same city: high temperature has an acute impact while there is a longer lag time in low temperature.

Ultrasound medical imaging has been widely applied in clinic diagnoses because of its real-time, non-invasiveness and convenience. However, it suffers from severe speckle noises. Until now, a lot of filtering algorithms have been proposed, but none of them is satisfactory. In this paper, four nonlinear filter methods, based on median filter, wavelet decomposition and anisotropic diffusion, are systematically reviewed. Finally, the prospect of the nonlinear filtering method is discussed.
Algorithms ; Humans ; Image Processing, Computer-Assisted ; methods ; Nonlinear Dynamics ; Ultrasonography

A dynamic multiway principle component analysis for on-line batch process monitoring and fault detection was proposed. It integrates the time-lagged windows of process dynamic behavior with the multiway principle component analysis (MPCA). Using multi-model instead of single model, the dynamic MPCA approach emphasizes particularly on-line process performance monitoring and fault defecting. On-line process monitoring of cephalosporin C fermentation was studied, the results demonstrate that the dynamic MPCA method is able to efficiently monitor performance of the fermentation process and exactly detect faults which results in extraordinary behavior of processes.
Cephalosporins ; biosynthesis ; Fermentation ; Forecasting ; Nonlinear Dynamics ; Principal Component Analysis ; methods

To extract texture features from medical images, the approaches for multi-scale complexity and multi-scale fractal dimension were proposed in this paper. The extracted texture features were used in the medical image retrieval experiments. The complexity measurements used include permutation entropy and 2D-C0 complexity. The former is used to analyze one dimensional signal, and the latter is used to analyze two dimensional one. Comparison experiments were carried out between our approaches and others' approaches in some literatures. Preliminary experimental results show that our approaches can effectively describe the texture information of medical images. Furthermore, the image retrieval results are encouraging.
Automation ; Diagnostic Imaging ; Humans ; Information Storage and Retrieval ; methods ; Nonlinear Dynamics