Qualitative research on the construction of pneumoconiosis rehabilitation station in Beijing from the perspective of ecosystem theory / 中国职业医学

Objective: To analyze the existing problems in the construction of pneumoconiosis rehabilitation station in Beijing under the framework of ecosystem theory, and put forward countermeasures. Methods: A total of four managers directly involved in the construction of three pneumoconiosis rehabilitation stations in Beijing and 12 rehabilitation doctors working in rehabilitation stations were selected as the interviewees using the judgment sampling method. Based on the perspective of ecosystem theory, an interview outline was designed to conduct a semi-structured interview with the interview subjects. In combination with literature data, the current situation, existing problems and solutions of pneumoconiosis rehabilitation station construction were analyzed. Results: There were still deficiencies in the construction of pneumoconiosis rehabilitation stations in Beijing. At the microscale level, pneumoconiosis patients could not make full use of family resources for active and effective pulmonary rehabilitation treatment, and family members lack of effective rehabilitation guidance and assistance for patients. At the medium-scale level, the resources of primary rehabilitation institutions were insufficient, the medical support for pneumoconiosis rehabilitation was insufficient, and the pneumoconiosis rehabilitation stations lacked a unified information management and technology platform. At the macroscale level, it has not established clear and specific requirements for the construction management and evaluation of pneumoconiosis rehabilitation stations, and there was social discrimination and prejudice against pneumoconiosis patients. Conclusion: It is necessary to improve the recognition of rehabilitation in primary medical and health institutions, strengthen education on the awareness of the disease and rehabilitation skills guidance for patients and their families, strengthen the responsibilities of technical support institutions in rehabilitation stations, promote the construction of primary rehabilitation stations and personnel training, make full use of information technology, promote information exchange and knowledge sharing, and ensure the quality of rehabilitation of pneumoconiosis.

Development and verification of the atmospheric dispersion model in microscale range for radioactive pollution / 中国辐射卫生

Because of the complex buildings, the wind flow and the pollution diffusion will be affected in the microscale such as urban neighborhood or the site of facility, the straight Gaussian plume model will not be available. Based on the Reynolds-Averaged Naiver-Stokes(RANS) method which was used to calculate the wind field with the Lagrange particle random walking model, the radioactive pollution diffusion model and microscale radiation environmental impact assessment software system were developed. This system can be used in the factory or city streets and other similar conditions for simulating radioactive pollutants diffusion behavior. The development of the system will provide technical tools for the microscale radiation environmental impact assessment in the future.

Microscale direct transesterification of microbial biomass with ethanol for screening of microorganisms by its fatty acid content

Abstract We present an improved method of direct transesterification suitable for the quantitative analysis of multiple dry samples for its fatty acid content, using a minimal amount of biomass and reactants. The method features an acid-catalyzed direct alcoholysis of microgram samples of dry biomass; the rationale behind the solvent and reagent proportions chosen is discussed. The method was validated using seven microbial strains with diverse lipid content (Saccharomyces cerevisiae, Saccharomyces boulardii, Candida tropicalis, Haematococcus pluvialis, Chlorella vulgaris, Spirulina platensis and Schizochytrium limacinum), and compared with a macroscale direct transesterification method, and with gravimetric analysis of lipids extracted with solvents. The microscale method showed a conversion of 98.06 ± 0.87% of the lipids, using approximately 3 mg of dry biomass, 1mL of 0.2M H2SO4 dissolved in anhydrous ethanol (the acid is the catalyzer and ethanol the reactant)). The mixture was maintained at 70 °C for 20 h with periodic mixing, and then extracted with 2mL n-heptane and analyzed by GC-FID. The lipid content was then calculated considering dilution and sample mass. This method is effective, reliable, and technically attractive for analytical and comparative purposes.

Influence of Microscale Attractive Interaction on Elastic Property of DNA Biofilm / 医用生物力学

Objective To investigate the influence of the microscale attractive interaction on the elastic properties of DNA film in multivalent ion solutions. Methods Kornyshev's electrostatic zipper model was employed to describe the interaction energy between the DNA strands. The thought experiment method and macroscopic continuum bar model were combined to predict the stress-strain relationship, prestress, and elastic modulus of the DNA biofilm.Results Given the packing conditions, the DNA film exhibited a tensile prestress and negative elastic modulus. The prestress of the DNA biofilm ranged from -1.52 MPa to 1.17 MPa, and its elastic modulus ranged from -4.2 MPa to 64 MPa. Conclusions In contrast with monovalent solutions, the microscopic attractive interactions in multivalent solutions caused the elastic properties of the DNA film to exhibit a non-monotonous relationship with the variation in the packing density and salt concentration. The tensile elastic properties were significantly different from the compressive ones, and the tensile/compressive prestress as well as the positive/negative elastic modulus transformed each other. These results can contribute to understanding the mechanism of viral replication and provide references for gene detection and gene therapy.

MECHANICAL CHARACTERIZATION OF CELLS AND TISSUES AT THE MICRO SCALE

Cell-substrate interactions are relevant for a number of biological and clinical applications e.g. to determine the effectiveness of medical implants. Cells are natural transducers that respond to and sense signals originating in their microenvironment. One important cell signaling mechanism is known as chemo-mechanical transduction. This refers to the use of external mechanical cues to initiate internal biochemical cellular processes and vice versa. One key factor to characterize and understand these interactions is the evaluation of the mechanical forces present at the cell-substrate interface. Recent advances in the micro and nanotechnology fields have allowed the development of new tools for the measurement of cellular and tissue forces. These tools have provided a means to study extremely low cellular and subcellular forces (pN-µN) as well as detailed small-scale tissue mechanics. This paper will review some of the most significant approaches to characterize the mechanical properties of cells and tissues at the micro-scale. Material properties, device fabrication, and design issues will be discussed.

Las interacciones célula-sustrato juegan un papel fundamental en gran número de aplicaciones biológicas y clínicas. Las células son transductores naturales que sensan y responden a señales en su entorno fisiológico. Uno de los mecanismos más importantes empleados en la caracterización de interacciones celulares es la transducción químico-mecánica, la cual se basa en la implementación de señales externas que se aplican a la célula con el fin de inducir diversos procesos bioquímicos al interior de ésta y viceversa. Los avances alcanzados en el campo de la micro y nanotecnología han permitido el desarrollo de nuevas herramientas para medir fuerzas a nivel celular o incluso sub-celular (pN-µN), y dilucidar la mecánica de los tejidos en la escala micrométrica. La presente revisión literaria describe algunos de los micro-dispositivos empleados actualmente para caracterizar las propiedades mecánicas de las células y tejidos en la micro-escala.