OBJECTIVETo compare the thermal conductivity of the related tissues along meridian line and non-meridian area.

METHODSForty healthy volunteers were observed with a infrared thermal imaging system.

RESULTSDuring heating the acupoint or the non-acupoint along the meridian line, the velocity of spreading of the temperature-increasing response along the meridian line was more easy and rapid, with a definite direction. However, during heating the non-meridian spots, the change of temperature was confined to the local area, with no definite direction. The spreading of skin temperature response along the meridian line was more rapid than the non-meridian area during both the two were heated simultaneously, and finally, 3 infrared radiant tracks along the meridian courses conformed basically with that of the classical three yin- meridians of the hand appeared.

CONCLUSIONThe thermal conductivity of the related tissues along the meridian line is better than that of non-meridian area and has definite direction, with differences in physical characteristics between them.

Owing to its unique physicochemical properties such as high surface area, notable biocompatibility, robust mechanical strength, high thermal conductivity, and ease of functionalization, 2D-layered graphene has received tremendous attention as a futuristic nanomaterial and its-associated research has been rapidly evolving in a variety of fields.With the remarkable advances of graphene especially in the biomedical realm, in vivo evaluation techniques to examine in vivo behavior of graphene are largely demanded under the hope of clinical translation. Many different types of drugs such as the antisense oligomer and chemotherapeutics require optimal delivery conveyor and graphene is now recognized as a suitable candidate due to its simple and high drug loading property. Termed as ‘ radio-graphene’, radioisotope-labeled graphene approach was recently harnessed in the realm of biomedicine including cancer diagnosis and therapy, contributing to the acquisition of in vivo information for targeted drug delivery. In this review, we highlight current examples for bioapplication of radiolabeled graphene with brief perspectives on future strategies in its extensive bio- or clinical applications.
Diagnosis ; Graphite ; Hope ; Nanostructures ; Theranostic Nanomedicine ; Thermal Conductivity

An apparatus was designed, based on the principle of Grayson's internal calorimetry, for the determination of the choroidal blood flow with thermistor as a sensing element. Experiments with water; 10%, 20%, 30% and 50% gelatin solution; living and dead rabbit eye and enucleated human eye showed that there was a linear relationship between the thermal conductivities and the currents required to raise the heating thermistor by 1 degree. Thus it was found that the Carslaw's law could be applied in these experiments In rabbit's eyes, thermistors were introduced into the suprachoroidal space after separating the sclera from the underlying choroid. At the same time, one of the vortex veins was cut right after the vein emerge from the sclera, and the amount of blood was absorbed and weighed. The results showed that when the blood flow was in the lower range, the thermal conductivity increased abruptly. When the blood flow increased, the increase in the thermal conductivity was at a more slower rate. In the physiological range of blood flow, however, there was a linear relationship between the blood flow and the changes in the thermal conductivity.
Calorimetry ; Choroid* ; Gelatin ; Heating ; Hot Temperature ; Humans ; Jurisprudence ; Rabbits* ; Sclera ; Thermal Conductivity ; Veins ; Water

PURPOSE: This study was designed to better understand the mechanism of low temperature burn and to show clinical cases of low temperature burn. METHODS: The local temperature increase of electric pad was investigated at 4 different surface cooling conditions. Blocks (5x5x2 cm3) made of silicone rubber, aluminum, or urethane foam were placed on the top of the electric pad, and temperature between the blocks and electric pad was measured up to 7 hours after switching on maximally (level 7). Each block has different thermal conductivity (TC) and TC of silicone rubber (0.2 W/m.degrees C) is similar to TC of human skin (0.37 W/m.degrees C). TC of aluminum is higher and TC of urethane foam is lower than TC of human skin. Experiments were performed on two occasions with or without a blanket covering over the electric pad and blocks. RESULTS: The initial surface temperature (18degrees C) of the electric pad under the silicone rubber block was elevated to 36.5degrees C at 1 hour, 41.8degrees C at 3 hours, 44.2degrees C at 5 hours, and 45.5degrees C at 7 hours. After covering the electric pad and blocks with a blanket, the temperature of the electric pad under the silicone rubber block was elevated to 40.9degrees C at 1 hour, 51.8degrees C at 3 hours, 56.1degrees C at 5 hours and 58.1degrees C at 7 hours. Under the same conditions, surface temperatures under the urethane foam and aluminum blocks were 70.8degrees C and 50.degrees C respectively at 7 hours. CONCLUSION: The local temperature increase of electric pad was dependent on the surface cooling conditions, heating time and blanket covering over the electric pad. The surface temperature increased to 56.1degrees C at 5 hours after blanket covering over the silicone block which temperature can cause severe injuries on the human skin within a minute.
Aluminum ; Beds ; Burns* ; Heating ; Hot Temperature ; Humans ; Silicon ; Silicone Elastomers ; Silicones ; Skin ; Thermal Conductivity ; Urethane

Dental ceramics have good aesthetics, biocompatibility, low thermal conductivity, abrasion resistance, and color stability. However, poor resistance to fracture and shrinkage during firing process have been limiting factors in their use, particularly in multiunit ceramic restorations. A new method for making all-ceramic crowns that have high strength and low processing shrinkage has been developed and is referred to as the Vita In-Ceram method. This study was performed to investigate the effect of Ce02 addition in borosilicate glasses on the strength of alumina-glass composites. Porous alumina compacts were prepared by slip casting and sintered at 1,100 degrees C for 2 hours. Dense composites were made by infiltration of molten glass into partially sintered alumina at 1,140 C for 4 hours. Specimens were polished sequentially from #800 to #2000 diamond disk, and the final surface finishing on the tensile side was received an additional polishing sequence through 1,cm diamond paste. Biaxial flexure test was conducted by using ball-on-three-ball method at a crosshead speed of 0.5mm/min. To examine the microstructural aspect of crack propagation in the alumina-glass composites, Vickers-produced indentation crack was made on the tensile surface at a load of 98.0 N and dwell time of 15 sec, and the radial crack patterns were examined by an optical microscope and a scanning electron microscope. The results obtained were summarized as follows ; 1. The porosity rates of partially sintered alumina decreased with the rising of firing temperature. 2. The maximum biaxial flexure strength of 423.5MPa. in alumina-glass composites was obtained with an addition of 3 mol% Ce02 in glass composition and strength values showed the aspect of decrease with the increase of Ce02 content. 3. The biaxial flexure strength values of alumina-glass composites were decreased with rising the firing temperature. 4. Observation of the fracture surfaces of alumina-glass composites indicated that the enhancement of strength in alumina-glass composites was due to the frictional or geometrical interlocking of rough fracture surfaces and ligamentary bridging by intact islands of materials left behind the fracture front.
Aluminum Oxide ; Ceramics ; Crowns ; Diamond ; Esthetics ; Eyeglasses ; Fires ; Friction ; Glass* ; Islands ; Porosity ; Thermal Conductivity

In general, the three major oral functions of edentulous patients-mastication, phonation, esthetics-can be rehabilitated by the complete dentures, and both the resin based complete denture and the metal based complete denture are commonly used by many clinicians today. For the sake of many advantages such as the excellent thermal conductivity, low volumetric change, high strength, low risk of fracture and the better patient's adaptation, the metal based complete dentures are indicated to the several cases. But, there are common failures of these type of dentures mainly by the fracture or the debonding between the resin structures and the metal frameworks which is caused by the discrepancies by the discrepancies of the flexural strength and the coefficient of thermal expansion. This is aggravated by the water contamination of the interface when exposed to the oral environment and results in the failure of complete denture treatment. So, the purpose of this study is to compare the bond strength and the fracture patterns of the gold alloy based and the Co-Cr alloy based complete dentures using the PMMA resins and the 4-META adhesive resins. The results of this study were as follows. 1. Both to th PMMA resin and the 4-META resin, the flexural bond strength of gold alloy is lower than that of Co-Cr alloy(p<0.05). 2. To the Co-Cr alloy, the bond strength of the 4-META resin is significantly higher tan that of PMMA resin(P<0.05). 3. The flexural strength of the group with the mechanical retention form is significantly higher than that of the group without retention form(P<0.05). 4. Comparing with the other groups, the fracture patterns of the group 3 are quite different from the group 1, 2, 5.
Adhesives ; Alloys* ; Denture Bases* ; Denture, Complete ; Dentures* ; Phonation ; Polymethyl Methacrylate ; Thermal Conductivity ; Triacetoneamine-N-Oxyl

In the surgical use of lasers in medicine, the laser light energy is transformed into heat within the tissue. As the result of this generation of heat, coagulation occurs and the tissue is carbonized and vaporized. The thermal effect depends upon the energy of the light radiation, its power and the irradiation time, the beam geometry, and the optical properties of the tissue itself, and also upon the thermal .parameters of the tissue such as its thermal conductivity and specific heat. In this experiment, to investigate the Neodymium-YAG laser effect on the bladder tissue and the extend of tissue damage at the various power and irradiation time under the same laser energy were aimed. Immediate after irradiation, the bladder tissues were fixed with formalin solution and H& E stained The extend of tissue damage was examined with light microscope. The following results were obtained: The effect of Neodymium-YAG laser irradiation on the bladder tissue was like a burn effect. Although the energy delivered to the tissue was the same, the resultant lesions created by the energy differed. The delivery of same energy in a low-power, long-duration manner made more tissue damage than a high-power, short-duration. Judging from the results of this experiment, it may be believed that a long period of irradiation time that there is sufficient time for the heat to be conducted into the surrounding tissue increases the zone of thermal damage and the coagulation necrosis.
Burns ; Carbon ; Formaldehyde ; Hot Temperature ; Lasers, Solid-State ; Necrosis ; Thermal Conductivity ; Urinary Bladder*

The step-temperature technique can be used to measure bio-tissue thermal physical parameters. During the derivation of the step-temperature technique, the measuring probe was assumed to be made of single thermistor sensing element, and the electrical power was assumed to be uniformly distributed throughout the probe bead. However, the probe bead in reality is made of multi-layer structure, and the electrical power is not uniformly distributed throughout the probe bead. In this paper, a mathematical model is built for the step-temperature technique for multi-layer structure probe bead, and a numerical simulation is made to analyze the effects of probe configuration. The physical meaning of the calibrated values of the probe parameters (bead radius and bead thermal conductivity) is also explained theoretically. The results show that the step-temperature technique is still valid for the measurement of bio-tissue thermal physical parameters for the multi-layer structure thermistor probe bead on condition that the bead radius and the bead thermal conductivity are obtained through pre- calibration.
Biomedical Engineering ; methods ; Body Temperature ; Body Temperature Regulation ; Humans ; Models, Theoretical ; Thermal Conductivity ; Thermography ; instrumentation ; Thermometers

Because of the compact structure of the field low temperature box for storage and transportation, which is due to the same small space where the compressor, the condenser, the control circuit, the battery and the power supply device are all placed in, the design for heat dissipation and ventilation is of critical importance for the stability and reliability of the box. Several design schemes of the heat dissipation design of the box were simulated using the FLOEFD hot fluid analysis software in this study. Different distributions of the temperature field in every design scheme were constructed intimately in the present study. It is well concluded that according to the result of the simulation analysis, the optimal heat dissipation design is decent for the field low temperature box for storage and transportation, and the box can operate smoothly for a long time using the results of the design.
Cryopreservation ; instrumentation ; Drug Storage ; Equipment Design ; Specimen Handling ; instrumentation ; Thermal Conductivity ; Transportation

High intensity focused ultrasound (HIFU) is a very complex transient process and can cause tissue coagulation necrosis. The cavitation and boiling behaviour of bubbles in the focal region play very important roles throughout an injury process. This paper reviews the research done by domestic and foreign scholars on behaviours of bubbles in HIFU irradiation process and summarizes in the focal region bubble cavitation and boiling generation, related detective means and relationships with hyperecho, temperature rise of the focus and injury shape.
Biophysical Phenomena ; High-Intensity Focused Ultrasound Ablation ; methods ; Humans ; Thermal Conductivity ; Thermodynamics