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

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

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

The parameters which can influence heat transfer of tongue were analyzed in order to reveal the reason why the tongue temperature fields of people with different diseases are distinct. Firstly, the research parameters were determined by experiment results, including the reference humidity of tongue surface, metabolic heat of tongue tissue, the entrance position of root vessel, the diameter of root vessel, the blood flow rate, and the bifurcation exponent of vascular tree. Then the effect of each parameter on the value and the distributing rule of tongue temperature field was analyzed by using a mathematic model of lingual temperature field. Results show that all these parameters have effects on the temperature value of tongue. The reference humidity of tongue surface, the metabolic heat of tongue tissue and the entrance position of root vessel are distinct influences on the distributing rule of tongue temperature.
Body Temperature ; physiology ; Humans ; Humidity ; Models, Theoretical ; Regional Blood Flow ; Thermal Conductivity ; Tongue ; blood supply ; physiology

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

The model establishment and numerical simulation of specific absorption rate (SAR) and the unsteady-state temperature distribution for radio frequency (RF) thermotherapy with double-frequencies and double-plates are presented in this paper. The model can correctly reflect the attenuation of electromagnetic wave in the biotissue. The variation of perfusion with temperature and the lower perfusion in tumor tissue are fully considered in the simulation of unsteady-state temperature profiles. Also presented are detailed analyses and discussions on the characteristics of SAR and temperature profiles, and the effects of the plates location and power as well as of the perfusion on the depth of effective treatment.
Computer Simulation ; Electromagnetic Fields ; Humans ; Hyperthermia, Induced ; Models, Theoretical ; Neoplasms ; therapy ; Temperature ; Thermal Conductivity

In this paper are reported the model establishment and numerical simulation of specific absorption rate(SAR) and the unsteady temperature distribution for the non-invasive tumor RF thermotherapy. The model can correctly reflect the attenuation of electromagnetic wave in the biotissue, the variation of perfusion with temperature and lower perfusion of the tumor tissue are fully considered in the simulation. These measures made simulation results more close to the clinical results. Also presented in the paper are detailed analyses and discussions on the characteristics of SAR of electromagnetic energy and the temperature profiles, the effects of the frequency and the perfusion on the depth for effective treatment. The simulation results are of great significance for directing the clinical application of tumor RF thermotherapy.
Electromagnetic Fields ; Humans ; Hyperthermia, Induced ; Models, Biological ; Neoplasms ; therapy ; Temperature ; Thermal Conductivity

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.

Bio-heat transfer in the tongue body is studied combining the mechanism of tongue inspection in Traditional Chinese Medicine. Parameters such as the temperature of lingual surface, the blood perfusion of the dog's tongue and so on are measured and the influences of the blood perfusion, the arterial blood temperature, the arterial cross-sectional areas and positions on the temperature distribution in the cross-sections are studied. Then the two-dimensional temperature fields in different cross-sections are numerically solved by the finite element method (FEM). The results show that the vascular cross-sectional areas vary with the elasticity change of the vessel walls resulting from the variation of the blood perfusion. And the temperature distribution in the cross-section mainly depends on the arterial cross-sectional areas and positions. The results can help to analyze the bio-heat transfer characteristic of the tongue. According to this method, the sectional temperature fields in whatever place of the tongue can be calculated under different blood perfusion and on the condition that the influence of the venous blood temperature on the temperature field of the tongue is considered. We can further probe into the relationship between the temperature fields of the lingual surface and that of cross-sections. This can provide the foundation for further investigation into the bio-heat transfer mechanism and the calculation on three-dimensional temperature fields of the tongue.
Animals ; Body Temperature ; physiology ; Dogs ; Finite Element Analysis ; In Vitro Techniques ; Models, Biological ; Regional Blood Flow ; Thermal Conductivity ; Tongue ; blood supply ; physiology