Housing conditions, cooking fuels, and health-related quality of life among rural middle-aged and elderly in northwest China: A ten-year balanced panel study.

To investigate the impacts of improving housing conditions and transitioning to clean cooking fuels on health-related quality of life (HRQOL) among middle-aged and elderly populations in rural China. METHODS: Using a 10-year longitudinal follow-up study, we examined changes in housing conditions, cooking fuel use, and HRQOL among 690 Chinese adults aged 45 above in rural areas. HRQOL was assessed using the European Quality of Life-5 Dimensions 3 Levels (EQ-5D-3L) questionnaire. Generalized estimating equations were utilized to analyze correlations between variables. RESULTS: Using four-period balanced panel data of 10 years, there were significant differences in the self-reporting of mobility, self-care, usual activities, pain / discomfort and anxiety / depression in rural middle-aged and elderly people (p < 0.05). In terms of the EQ-5D index score and EQ-VAS score, showed a decreasing trend (p < 0.05). The housing area, housing material type, utilization of sanitary toilets, separation of housing and kitchen were separated and non-solid fuels used as cooking fuel were significantly associated with high HRQOL (p < 0.05). CONCLUSIONS: This study found that good housing conditions and the use of non-solid cooking fuel had positive effects on health-related quality of life of middle-aged and elderly people in rural areas of northwest China.

The mediation path of physical multimorbidity on the vulnerability to health-related poverty of rural aging families in Ningxia, China: A cross-sectional survey.

Background: Vulnerability to health-related poverty can predict the probability of families falling into poverty due to health risk impact. In this study, we measured the vulnerability to health-related poverty and examined the mediation path of physical multimorbidity on the vulnerability to health-related poverty of rural aging families in Ningxia, China. Methods: This cross-sectional study was conducted in Ningxia, China, in February 2019. A multi-stage stratified cluster-randomized design was used to obtain a representative sample in each county. We included participants aged 60 years and older, who had lived there for more than 1 year. A total of 3,653 rural residents older than 60 years old were selected as the research subjects. The three-stage generalized least square method was used to calculate the expected vulnerability to poverty. We used mediating effect model to test the mediation path of poverty vulnerability related to the physical multimorbidity. Results: Under different poverty line standards, i.e., $1.9/day as low vs. $3.1/day as the high poverty line, the proportion of families that could fall into poverty in the future was 5.3 and 53.7%, respectively. The prevalence of chronic diseases and physical multimorbidity among rural residents >60 years old was 64.62 and 21.24%, respectively. The results of mediating effect test showed that self-rated health status (indirect effect a × b = -0.0052), non-agricultural employment (a × b= -0.0046), household cattle production (a × b = 0.0004), housing type (a × b = -0.0008), gift expenses (a × b = 0.0006) and loan for illness (a × b = 0.0034) were the mediation paths of poverty vulnerability related to the physical multimorbidity. Conclusions: Concerted efforts are needed to reduce poverty vulnerability related to the physical multimorbidity. The strategy of alleviating poverty should emphasis on promoting non-agricultural employment of vulnerable groups sustainability and developing rural economy, which are important paths to reduce family's vulnerability to health-related poverty.

The impact of healthcare reform on the dynamic changes in health service utilization and equity: a 10-year follow-up study.

In the past decade, the government of China has implemented healthcare reforms to provide universal access to healthcare by 2020. We aimed to systematically analyse the dynamic changes in health services and equity during the past 10 years to understand the correlation between health services and social-economic status. We performed a longitudinal study in which we extracted aggregated data mainly from a project (2009, 2011, 2012, 2015, 2019). A multi-stage stratified cluster randomized design was used to obtain a representative sample in each county. Concentration indexes were used to analyse the equity of the changes in utilization. We built multivariate random-effects generalized least squares regression models with the panel data to test whether the rate of receiving a medical consultation in the last 2 weeks or the rate of hospital admission or the prevalence of chronic illness was associated with social-economic status including education level and rural disposable income per capita. We found declines in both the rate of not receiving a medical consultation during the last 2 weeks (P < 0.05 intervention group) and the rate of hospital avoidance (P < 0.05) from 2009 to 2019. The equity in residents' health service utilization has improved constantly. We additionally found that rural disposable income per capita is a protective factor for the rate of a receiving a medical consultation during the last 2 weeks and the rate of hospital admission. China's 2009 healthcare reform have positively influenced utilization rates and equity in health service utilization in the past decade, a range of health service-targeted strategies are needed including strengthen the prevention and treatment of chronic diseases, focus attention on the health status of elderly residents and improve social-economic status, especially the level of education.

Potential effect of pulmonary fluid viscosity on positive end-expiratory pressure and regional distribution of lung ventilation in acute respiratory distress syndrome.

BACKGROUND: Computational fluid dynamic simulations have showed that the elevated viscosity of pulmonary fluids may increase the likelihood of airway closure, thus exacerbating inhomogeneity of regional lung ventilation. Unfortunately, there have been few studies directed toward measurements of viscosity of pulmonary fluids and its effect on airway opening pressure and regional distribution of lung ventilation in acute respiratory distress syndrome. METHODS: In this study, pulmonary fluids from 8 ARDS patients were measured using a cone and plate rheometer on days 1, 3, 7 and 14 in the treatment of the disorder. Ventilator settings were simultaneously recorded, including tidal volume, positive end-expiratory pressure, fraction of inspired oxygen (FiO2), and so on. The regional distribution of lung ventilation was monitored by a bedside electrical impedance tomography system. FINDINGS: The results showed that rheological properties of pulmonary fluids behaved as either Newtonian or non-Newtonian across all patients studied. Significant intersubject and intrasubject variations in measured viscosities were observed, spanning ranges from approximately 1 cP to 7 × 104 cP at shear rates between 0.075-750 s-1. The product of the positive end-expiratory airway pressure and fraction of inspired oxygen was well correlated with fluid viscosity in patients with high viscosity pulmonary fluids. Furthermore, lung ventilation in these patients was highly inhomogeneous and influenced by rheology of pulmonary fluids. INTERPRETATION: The current findings provided the direct clinical data for theoretical models of airway reopening and may have important clinical implications in explaining inhomogeneity of lung ventilation and selecting initial levels of positive end-expiratory pressure in mechanically ventilated patients.

Determination of rheology and surface tension of airway surface liquid: a review of clinical relevance and measurement techniques.

By airway surface liquid, we mean a thin fluid continuum consisting of the airway lining layer and the alveolar lining layer, which not only serves as a protective barrier against foreign particles but also contributes to maintaining normal respiratory mechanics. In recent years, measurements of the rheological properties of airway surface liquid have attracted considerable clinical attention due to new advances in microrheology instruments and methods. This article reviews the clinical relevance of measurements of airway surface liquid viscoelasticity and surface tension from four main aspects: maintaining the stability of the airways and alveoli, preventing ventilator-induced lung injury, optimizing surfactant replacement therapy for respiratory syndrome distress, and characterizing the barrier properties of airway mucus to improve drug and gene delivery. Primary measuring techniques and methods suitable for determining the viscoelasticity and surface tension of airway surface liquid are then introduced with respect to principles, advantages and limitations. Cone and plate viscometers and particle tracking microrheometers are the most commonly used instruments for measuring the bulk viscosity and microviscosity of airway surface liquid, respectively, and pendant drop methods are particularly suitable for the measurement of airway surface liquid surface tension in vitro. Currently, in vivo and in situ measurements of the viscoelasticity and surface tension of the airway surface liquid in humans still presents many challenges.

Multiple mutations of lung squamous cell carcinoma shared common mechanisms.

Lung squamous cell carcinoma (LUSC) is a subtype of non-small cell lung cancers which is the cause of 80% of all lung cancer deaths. The genes that highly mutated in patients with LUSC and their roles played in the tumorigenesis remains unknown. Data of patients with Lung squamous cell carcinoma (LUSC) were retrieved from The Cancer Genome Atlas (TCGA). Differentially expressed genes were identified between control and cancer samples. Patients and controls can be separated by mRNA expression level showing that the between-group variance and totally 1265 genes were differentially expressed between controls and patients. Top genes whose mutations highly occurred in patients with LUSC were identified, most of these genes were shown to be related with tumorigenesis in previous studies. All of the genes mostly mutated were independently correlated with expression levels of all genes. These mutations did not show the trend of co-occurrence. However, the influenced gene of these mutations had overlaps. After studying the intersection of these genes, a group of shared genes were identified. The shared pathways enriched which played critical role in LUSC were identified based on these shared genes. Different mutations had contribution to the progression of LUSC. Though these genes involved different specific mechanisms, most of them may share a common mechanism which is critical for LUSC. The results may suggest a neglected mechanism and also indicate a potential target for therapies.

[Design and Implementation of a Medical Nitric Oxide Flow Control Device].

Medical nitric oxide(NO)flow control system plays an important role in lowering pulmonary hypertension.The design requirements,overall scheme,delivery system and hardware circuits of a medical NO flow control system were introduced in this paper.Particularly,we proposed the design of NO delivery system and hardware circuits in detail.To deliver nitric oxide of a variable concentration,the designed system needs to work with a ventilator.The system can adjust and monitor the inhaled nitric oxide concentrations and send out sound and light alarms when the inhaled nitric oxide concentrations are out of the set range.To validate reliability and efficacy,we measured specifications such as linearity,stability and response time of the proposed NO flow control system by continuously administering nitric oxide into inspiratory circuit to deliver nitric oxide of variable concentrations to a test lung.The experiments showed that these specifications can meet the desired requirements.

An estimation of mechanical stress on alveolar walls during repetitive alveolar reopening and closure.

Alveolar overdistension and mechanical stresses generated by repetitive opening and closing of small airways and alveoli have been widely recognized as two primary mechanistic factors that may contribute to the development of ventilator-induced lung injury. A long-duration exposure of alveolar epithelial cells to even small, shear stresses could lead to the changes in cytoskeleton and the production of inflammatory mediators. In this paper, we have made an attempt to estimate in situ the magnitudes of mechanical stresses exerted on the alveolar walls during repetitive alveolar reopening by using a tape-peeling model of McEwan and Taylor (35). To this end, we first speculate the possible ranges of capillary number (Ca) ≡ µU/γ (a dimensionless combination of surface tension γ, fluid viscosity µ, and alveolar opening velocity U) during in vivo alveolar opening. Subsequent calculations show that increasing respiratory rate or inflation rate serves to increase the values of mechanical stresses. For a normal lung, the predicted maximum shear stresses are <15 dyn/cm(2) at all respiratory rates, whereas for a lung with elevated surface tension or viscosity, the maximum shear stress will notably increase, even at a slow respiratory rate. Similarly, the increased pressure gradients in the case of elevated surface or viscosity may lead to a pressure drop >300 dyn/cm(2) across a cell, possibly inducing epithelial hydraulic cracks. In addition, we have conceived of a geometrical model of alveolar opening to make a prediction of the positive end-expiratory pressure (PEEP) required to splint open a collapsed alveolus, which as shown by our results, covers a wide range of pressures, from several centimeters to dozens of centimeters of water, strongly depending on the underlying pulmonary conditions. The establishment of adequate regional ventilation-to-perfusion ratios may prevent recruited alveoli from reabsorption atelectasis and accordingly, reduce the required levels of PEEP. The present study and several recent animal experiments likewise suggest that a lung-protective ventilation strategy should not only include small tidal volume and plateau pressure limitations but also consider such cofactors as ventilation frequency and inflation rate.

A micromechanical model for estimating alveolar wall strain in mechanically ventilated edematous lungs.

To elucidate the micromechanics of pulmonary edema has been a significant medical concern, which is beneficial to better guide ventilator settings in clinical practice. In this paper, we present an adjoining two-alveoli model to quantitatively estimate strain and stress of alveolar walls in mechanically ventilated edematous lungs. The model takes into account the geometry of the alveolus, the effect of surface tension, the length-tension properties of parenchyma tissue, and the change in thickness of the alveolar wall. On the one hand, our model supports experimental findings (Perlman CE, Lederer DJ, Bhattacharya J. Am J Respir Cell Mol Biol 44: 34-39, 2011) that the presence of a liquid-filled alveolus protrudes into the neighboring air-filled alveolus with the shared septal strain amounting to a maximum value of 1.374 (corresponding to the maximum stress of 5.12 kPa) even at functional residual capacity; on the other hand, it further shows that the pattern of alveolar expansion appears heterogeneous or homogeneous, strongly depending on differences in air-liquid interface tension on alveolar segments. The proposed model is a preliminary step toward picturing a global topographical distribution of stress and strain on the scale of the lung as a whole to prevent ventilator-induced lung injury.

[The study of simulation system for cardiopulmonary bypass cardiac surgery].

According to the clinical requirements of cardiopulmonary bypass surgery, this paper established a simulation system for cardiac surgery which consists of venous reservoir, variable balance chamber, blood suction bag, ventricle suction bag, resistance valves, pressure gauges and tubings. Using the proposed system, perfusionists can mimic the implementation of pre-established surgery strategy, predict various abnormal conditions in the operation, and accordingly take the urgent actions so as to improve the success rate of surgery and to ensure the safety of patients.

The discriminant analysis of the voice expression of emotion--focus on the nursing experience-.

The characteristics of emotional expression in everyday life vary significantly depending on one's life experiences, role in society, and other factors, especially special occupation experiences. We focus on the nursing experience. The purpose of this study is to establish a method to discriminate voice of nurse's emotion. We performed the pronunciation experiment at first and through the sound analysis, extracted the effective speech parameters. For make clear of the differences of these parameters between emotions and discriminate emotions, we performed the multiple comparisons and discriminant analysis. In the result, found that the speech parameters different between emotions and these affected parameters are different at two groups based on nursing experience. In four emotions of our study, the Sadness is easy discriminant emotion; the Joy is most difficult to discriminate. Through the discriminant analysis, found two stable speech parameters.

[Control and testing methods for blood bump in heart assistant and replacement devices].

Using extracorporeal circulation for cardiopulmonary bypass is the first step for the successful cardiac surgery, and the blood pump is the key component in extracorporeal circulation devices, the control and measurement of mechanical-fluid parameters such as flow rate and pressure are very important to guarantee the successful cardiac surgery. This paper reviews several control methods of the blood pump based on the flow rate/pressure, heart rate, ventricular work and blood assist index, and also discusses the direct and indirect measurements of the flow rate and pressure. This review concludes with the main possible trends for the further development of the blood pump control and testing methods.

[Magnetic field numerical calculation and analysis for magnetic coupling of centrifugal blood pump for extracorporeal circulation].

This paper mainly studies the driving system of centrifugal blood pump for extracorporeal circulation, with the core being disc magnetic coupling. Structure parameters of disc magnetic coupling are related to the ability of transferring magnetic torque. Therefore, it is necessary to carry out disc magnetic coupling permanent magnet pole number (n), air gap length (L(g)), permanent magnet thickness (L(m)), permanent magnet body inside diameter (R(i)) and outside diameter (R(o)), etc. thoroughly. This paper adopts the three-dimensional static magnetic field edge element method of Ansys for numerical calculation, and analyses the relations of magnetic coupling each parameter to transmission magnetic torque. It provides a good theory basis and calculation method for further optimization of the disc magnetic coupling.

Control system design for a Continuous Positive Airway Pressure ventilator.

Continuous Positive Airway Pressure (CPAP) ventilation remains a mainstay treatment for obstructive sleep apnea syndrome (OSAS). Good pressure stability and pressure reduction during exhalation are of major importance to ensure clinical efficacy and comfort of CPAP therapy. In this study an experimental CPAP ventilator was constructed using an application-specific CPAP blower/motor assembly and a microprocessor. To minimize pressure variations caused by spontaneous breathing as well as the uncomfortable feeling of exhaling against positive pressure, we developed a composite control approach including the feed forward compensator and feedback proportional-integral-derivative (PID) compensator to regulate the pressure delivered to OSAS patients. The Ziegler and Nichols method was used to tune PID controller parameters. And then we used a gas flow analyzer (VT PLUS HF) to test pressure curves, flow curves and pressure-volume loops for the proposed CPAP ventilator. The results showed that it met technical criteria for sleep apnea breathing therapy equipment. Finally, the study made a quantitative comparison of pressure stability between the experimental CPAP ventilator and commercially available CPAP devices.

[Study on optimal selection of structure of vaneless centrifugal blood pump with constraints on blood perfusion and on blood damage indexes].

This paper is aimed to study the optimal selection of structure of vaneless centrifugal blood pump. The optimal objective is determined according to requirements of clinical use. Possible schemes are generally worked out based on structural feature of vaneless centrifugal blood pump. The optimal structure is selected from possible schemes with constraints on blood perfusion and blood damage indexes. Using an optimal selection method one can find the optimum structure scheme from possible schemes effectively. The results of numerical simulation of optimal blood pump showed that the method of constraints of blood perfusion and blood damage is competent for the requirements of selection of the optimal blood pumps.

[The study of noninvasive ventilator impeller based on ANSYS].

An impeller plays a significant role in the non-invasive ventilator. This paper shows a model of impeller for noninvasive ventilator established with the software Solidworks. The model was studied for feasibility based on ANSYS. Then stress and strain of the impeller were discussed under the external loads. The results of the analysis provided verification for the reliable design of impellers.

[Design of a noninvasive ventilator's turbine].

The design principles of a noninvasive ventilator's turbine are studied and discussed in this paper. The design is completed from its several aspects and in combination of related theories, using SolidWorks tools. Abundant experimental results prove that this design's technical specifications meet all the requirements.

[Comparative study of hepatocirrhosis case diagnosed by traditional Chinese medicine based on grey system and fuzzy cluster].

In view of the problem of TCM diagnosis, grey relational analysis and fuzzy cluster are applied to TCM diagnosis of hepatocirrhosis and are presented in this paper. The validity of the two methods has been assessed through 900 cases in Shanghai. The results are in good agreement with the diagnosis of hepatocirrhosis made by the expert group, thus showing the fuzzy technology is of significance to the development of TCM modernization in an objective way.

[The testing techniques of intraocular lenses].

This paper outlines kinds of index of eyes' optical effect and some different testing methods of intraocular lenses' optical quality.