494 research outputs found
Efficiency of the phasor plot approach for the analysis of the antimicrobial properties of nanoparticles using two photon microscopy
About the productivity of shaft air heater located along the perimeter of pithead
In the existing shaft air heaters that heat the air for air suppliers in the cold season heater channel is used. Part of the air from heater goes to the channel, another one is sucked through pithead by general shaft pressure drawdown formed by main ventilation installation. Wherein, mix of two air flow leads to shaft heat regime violation that could break the pressurization of intertubular sealers. Moreover, heater channel design is associated with additional expenditures.
Paper describes the air heater, located in the pithead. The location of a heater in one line along pithead perimeter is the key feature. In this case there is no need to design heater channel, thus, there is no problem with mix of cold and heated air flows.
Air processing it the heater located on the perimeter of pithead and mix of cold and heated air flows in the supplier from the channel was modeled in the software Soldworks flow simulation. The comparative analysis of both types of heater proved efficiency of proposed design of installation, smooth propagation of heat field along the all cross-section of air supplier, decrease of consumption of electric power for air processing and installation operation by transformation negative natural common excavation traction to positive
Research on lymphedema by method of high-resolution multiphoton microscopy
In this paper results of iv-vivo measurements for healthy volunteers and people, with verified diagnosis of lymphedema, obtained with two-photon tomography with fluorescence lifetime imaging microscopy (FLIM) are presented. The papillary layer of the skin was analyzed at a depth of about 100 μm. The purpose of this study is to evaluate the lifetime of autofluorescence in the papillary dermis of healthy tissue and with the initial stage of lymphedema. In the course of the study, a small redistribution of autofluorescence lifetimes was observed for healthy volunteers and people with lymphedema disease. The research was carried out on the equipment of MPTflex (JenLab GmbH)
Results of modelling of mine ventilation with air curtain installed into downcast and upcast shafts
Existing mine air heaters (MAH) that heat the air supplied into downcast shafts during the cold period are equipped with a heat channel. A part of the air from a MAH goes through a heat channel. Another part is sucked through a pit head by general depression created by a shaft main fan. That raises a problem of mixing of two air streams, which disturbs thermal regime in the shafts and could lead to violation of safety rules, in particular, create a breach of sealing of intertubular seals. Besides, there is a concern of energy saving during ventilation at underground mining enterprises. One of the reasons for energy efficiency reduce during air supply to a mine are external leaks appeared during ventilation by a suck method.
The article presents proposed solution for both problems using air curtain. During air preparation in the cold period, it is proposed to place air curtain in an air downcast shafts above the junction of a heat channel and a shaft. That is done in order to prevent air infiltration (sucking) through a pit head. According to the paper air curtain should be used in the ventilation shaft to decrease outside air leakage in order to increase energy efficiency of a main fan performance. It is determined during mathematical modelling (in SolidWorks Flow Simulation software) of ventilation and air preparation that air curtain can increase efficiency of MAH and decrease energy consumption on ventilation
The in vivo quantitative assessment of the effectiveness of low-dose photodynamic therapy on wound healing using optical coherence tomography
The effect of low-dose photodynamic therapy on in vivo wound healing was investigated using optical coherence tomography. This work aims to develop an approach to quantitative assessment of the wound’s state during wound healing including the effect of low-dose photodynamic therapy using topical application of two different photosensitizers, 5-aminolevulinic acid and methylene blue, and two laser doses of 1 J/cm2 and 4 J/cm2. It was concluded that the laser dose of 4 J/cm2 was better compared to 1 J/cm2 and allowed the wound healing process to accelerate
Application of multiphoton imaging and machine learning to lymphedema tissue analysis
The results of in-vivo two-photon imaging of lymphedema tissue are presented. The study involved 36 image samples from II stage lymphedema patients and 42 image samples from healthy volunteers. The papillary layer of the skin with a penetration depth of about 100 μm was examined. Both the collagen network disorganization and increase of the collagen/elastin ratio in lymphedema tissue, characterizing the severity of fibrosis, was observed. Various methods of image characterization, including edge detectors, a histogram of oriented gradients method, and a predictive model for diagnosis using machine learning, were used. The classification by “ensemble learning” provided 96% accuracy in validating the data from the testing set
nsuring the safety and energy efficiency of ventilation of shafts and mines that use the air recycling system
The paper describes the possible failures in the automation ventilation system with partial return use of upcast air from a shaft or mine (during recirculation). Existing ventilation systems use recirculation in the main ventilation mining, through which air is delivered from an underground mining enterprise. It is proposed to install automatic ventilation doors (AVD). They allow to change the aerodynamic resistance of the mine, i.e. control flow rate of air discharged from a mine (shaft). If an AVD is damaged the dangerous case could arise even in a normal ventilation mode due to the fact that mentioned negative control means can block the main path of air movement. In this case air from the air-supplying barrels is directed to the ventilation barrel through the recirculation loop bypassing the mining sites dedicated for ventilation. At the time of accident, when the main fan unit (MFU) is reversed, such a failure makes the situation even more dangerous due to the unpredictable path of flue gases.
In the method described it is proposed to install the AVD in the mines of the main directions and close them only during the period of the MFU reverse. When the closing AVD and forced draft fan of the main air heater work together and discharge air in the reverse mode, the time dedicated for switching of the main heater to the reverse mode is reduced. After the gradual opening of the AVD in the shaft (mine) a reversible mode of ventilation is installed.
The method proposed allows energy and resource savings for ventilation and air preparation both in normal and emergency modes while meeting the safety requirements for mining operations
In vivo quantification of the effectiveness of topical low-dose photodynamic therapy in wound healing using two-photon microscopy
The effect of low-dose photodynamic therapy on in vivo wound healing with topical application of 5-aminolevulinic acid and methylene blue was investigated using an animal model for two laser radiation doses (1 and 4 J/cm2). A second-harmonic-generation-to-auto-fluorescence aging index of the dermis (SAAID) was analyzed by two-photon microscopy. SAAID measured at 60–80 μm depths was shown to be a suitable quantitative parameter to monitor wound healing. A comparison of SAAID in healthy and wound tissues during phototherapy showed that both light doses were effective for wound healing; however, healing was better at a dose of 4 J/cm2
The effect of photodynamic therapy with topical application of 5-aminolevulinic acid on skin wound healing process by multiphoton microscopy
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