A low-cost invasive microwave ablation antenna with a directional heating pattern

Microwave ablation(MWA) is a cancer treatment method. The tumor tissue absorbs electromagnetic energy, which heats and kills it. A microwave ablation antenna plays a critical role in this process. Its radiation field must completely cover the tumor but not the healthy tissue. At present, the radiation pattern of most invasive ablation antennas is spherical.However, in the clinic, the shape of some tumors may be asymmetrical or the antenna cannot be inserted into the center of the tumor for some other reason. In order to solve these problems, a directional heating antenna for microwave ablation is proposed in this paper. The proposed antenna, operating at 2.45 GHz, consists of a monopole and a reflector. The feed is given by a substrate integrated coaxial line(SICL) and coplanar waveguide(CPW). The omnidirectional radiation field of the monopole is reflected by a reflector that is extended from the outer conductors of the SICL to form a directional radiation field. The impedance matching network is designed on SICL to match the antenna to 50 Ω. The antenna is fabricated using a mature printed circuit board(PCB). The reflection coefficient of the antenna in porcine liver tissue measured by a vector network analyzer shows good agreement with the simulations. Then, an ablation experiment in porcine liver is conducted with power of 10 W for 10 min, and the experimental results confirm the validity of the design.

Metabolomics characterization of Qingwei San on oral ulcer in db/db mice with stomach heat pattern

Objective:To characterize the effects of Qingwei San(QWS)on diabetic oral ulcer(OU)mice with stomach heat pattern through metabolomic analysis.Methods:A stomach heat pattern mouse model was established by treating C57BLKS/J Leprdb/db(db/db)mice with dried Zingiber officinale Rosc.rhizome(Z.officinale,Gan Jiang)decoction by gavage.All model mice had blood glucose levels of≥11.1 m M.Subsequently,OU was induced by Na OH cauterization.After 1 week of administration of QWS,non-targeted metabolomic analysis of serum was conducted using ultra high performance liquid chromatography coupled with mass spectrometry(UHPLC-MS/MS).Results:The non-targeted metabolomics results indicated that tryptophan metabolism,2-oxocarboxylic acid metabolism,serotonergic synapses,amino sugar and nucleotide sugar metabolism,and amino acid biosynthesis were involved in the therapeutic effects of QWS,with tryptophan metabolism playing a predominant role.Conclusion:QWS treatment can significantly improve the pathological status of diabetic OU mice with stomach heat pattern.QWS may regulate the release of inflammatory factors through the tryptophan metabolism pathway.

Perceptions and Controversies on Cholera in the Traditional Chinese Medicine Field in the Late Qing Dynasty

At the beginning of the initial cholera outbreak in China,Wang Qingren(王清任),after years of clinical trials,became an early representative who discovered the infectious characteristics and observed the course of cholera in the field of traditional Chinesse medicine(TCM).Kou Langao(寇兰皋)and Xu Zimo(徐子默),both medical practitioners,constructed a diagnosis and treatment system for cholera with cold patterns under the theory of typhoid.They represented“School of Cholera with Cold Patterns”(SCCP).In the 1860s,with the influence of Wang Shixiong’s(王士雄)studies on the nature of cholera under the theory of epidemic febrile disease,the“School of Cholera with Heated Patterns”(SCHP)prevailed thereafter.The two schools complemented each other in theories and contributed to the integrity of TCM in cholera diagnosis and treatment.By reviewing previous literature,books,clinical cases,and historical materials in medical field,this article aims 1)to summarise the influence of TCM on the cognitive development towards cholera in the late Qing dynasty;2)to explore the origin of the controversy between SCCP and SCHP from historical evidence;3)to summarize the historical lessons from the debate over cholera in TCM based on the principle of treatment based on pattern identification,and offer suggestions for the current prevention and treatment of new diseases using TCM.

Simulation Study of Heat Flux Deposition Pattern on the Surface of HT-7 Toroidal Limiters

The heat flux deposition pattern on the toroidal limiters installed in HT-7 was simulated with ANSYS code. The simulation model was established with the ripple of the magnetic field. The heat deposition pattern and temperature distribution on the surface of the toroidal linfiters were obtained. A comparison of the results obtained with and without the shaped tiles, used to reduce the heat flux on the leading edge of the limiters, was made. The maximum heat load allowed at the leading edge was about 1.8 MW/m2 because of the poor power removing capacity on the ends of the limiters. This approach can also be applied to other devices with a limiter configuration in a circular cross-section shape.

The Morphology of Patterning with Pseudoplastic Metal Nanoparticle Fluids during Heat Treatment

A pseudoplastic metal nanoparticle fluid （PMNF） is used in nanoimprint to fabricate semiconductors and func- tional devices. The evaporation of the solvent and the sintering of the Au PMNF are investigated. The key parameters, which influence the morphology of patterning, such as the radius of metal particles, the concentra- tion of metal particles, the Hamaker constant of the solvent, viscosity of the fluids and the evaporation velocity, are analyzed. Based on a two-sphere sintering model, the equations are derived, which represent the relationships between the relative shrinkage and radius of the metal particles, sintering temperature and time. The optimal parameters for the heat treatment are provided in nanoimprint.

Research on heat dissipation characteristics of magnetic fluid bearings under multiple field coupling effects

This paper analyzes the sources of heat losses in magnetic fluid bearings,proposes various cou-pling relationships of physical fields,divides the coupled heat transfer surfaces while ensuring the continuity of heat flux density,and analyzes the overall heat dissipation pathways of the bearings.By changing parameters such as input current,rotor speed,and inlet oil flow rate,the study applies a multi-physics field coupling method to investigate the influence of different parameters on the temper-ature field and heat dissipation patterns of the bearings,which is then validated through experi-ments.This research provides a theoretical basis for the optimal design of magnetic fluid bearing sys-tems.

Prediction of Cold and Heat Patterns Using Anthropometric Measures Based on Machine Learning

Objective： To examine the association of body shape with cold and heat patterns, to determine which anthropometric measure is the best indicator for discriminating between the two patterns, and to investigate whether using a combination of measures can improve the predictive power to diagnose these patterns. Methods： Based on a total of 4,859 subjects （3,000 women and 1,859 men）, statistical analyses using binary logistic regression were performed to assess the significance of the difference and the predictive power of each anthropometric measure, and binary logistic regression and Naive Bayes with the variable selection technique were used to assess the improvement in the predictive power of the patterns using the combined measures. Results： In women, the strongest indicators for determining the cold and heat patterns among anthropometric measures were body mass index （BMI） and rib circumference; in men, the best indicator was BMI. In experiments using a combination of measures, the values of the area under the receiver operating characteristic curve in women were 0.776 by Naive Bayes and 0.772 by logistic regression, and the values in men were 0.788 by Naive Bayes and 0.779 by logistic regression. Conclusions： Individuals with a higher BMI have a tendency toward a heat pattern in both women and men. The use of a combination of anthropometric measures can slightly improve the diagnostic accuracy. Our findings can provide fundamental information for the diagnosis of cold and heat patterns based on body shape for personalized medicine.