It is observed that the application of magnetic field increases heat transfer rate within tumor tissues which in turn attribute to an enhancement of temperature about 316 K or above for hyperthermic treatment in cancer therapy.Leipzig-style skin brachytherapy applicators are an excellent choice for the treatment of small surface lesions, since they can be used with a high dose rate source to produce a tightly constrained treatment field on the desired area of the skin. The dosimetry of these applicators is challenging to independently verify due to their small dimensions, complex energy spectrum and steep dose gradients. In particular the close proximity of the brachytherapy source to the treatment region is cause for concern, since small variations in the position of the radioactive source may significantly affect the resulting dose distribution. The aim of this work was to assess the dosimetry of these applicators using three independently techniques and use these results to examine the effect of variation in source position on the dose distribution. Simulation of different sized applicators in conjunction with a Gammamed + Ir192 source was performed using the EGSnrc Monte Carlo code. Dose distributions at the prescription depth and at the surface generated by Monte Carlo were compared to the outputs of a commercially available treatment planning system and measurements using radiochromic film. Source displacements of up to 0.5 mm in the vertical direction, 0.65 mm in the horizontal direction, and rotations of the source by up to 5° were all simulated. Changes in dose of over 6% at the prescription point and reductions in coverage at the 100% isodose level of several millimetres were observed even for small shifts of the source from its intended position. This work demonstrates that variation in the position of the radiation source is the dominant source of uncertainty in the use of these types of applicators. Centres wishing to perform treatments using these applicators are advised to take steps to control the uncertainty and ensure it remains at an acceptable level.
  The influence of the skin-electrode-amplifier interface and the input impedance of ECG recording amplifiers on transient response performance is investigated using accurate modeling of surface contact electrodes. The paper aims to establish the input impedance requirements of ECG recording amplifiers based on the electrical properties of the electrodes.
 
  The IEC 60601 standard stipulates the performance requirements for electrocardiographs. Analyses and simulation of both dc and ac modes of coupling the electrodes to the input of the amplifier have been undertaken using an accurate double time-constant model of the electrodes in order to establish design constraints for amplifier input impedance to meet this performance specification. These have been backed up with bench tests.
 
  Investigations carried out indicate that the minimum 10 MΩ resistance at the amplifier input recommended in the specification is insufficient when using some modern adhesive electrodes and increasingly popular un-gelled or dry electrodes. Design constraints are established based on the electrical properties of the electrodes. These constraints suggest that the input impedance of the amplifier should be as high as 10 GΩ and the amplifier ac coupled cut-off frequency should not to be higher than 0.05 Hz for all the electrode models considered.
 
  Signal distortions in the form of false S-wave creation and depression of the S-T segment have been observed when the previously recommended 10 MΩ input impedance is used in the amplifier. This distortion can lead to clinical misdiagnosis but can be avoided if the design constraints established in the paper are adopted.
 Signal distortions in the form of false S-wave creation and depression of the S-T segment have been observed when the previously recommended 10 MΩ input impedance is used in the amplifier. This distortion can lead to clinical misdiagnosis but can be avoided if the design constraints established in the paper are adopted.This study was to evaluate dose reduction and resulting image quality of a new synthetic thyroid shield based on silicon rubber (SR)-lead (Pb) composites and compare to tungsten paper (WP) and a Radibabarrier thyroid shields in CT examination of the neck. The synthetic SR-Pb thyroid shield had a Pb percentage from 0 to 5 wt% and a thickness of 0.6 cm. Scanning on the neck of an anthropomorphic phantom was performed with and without the SR-Pb, WP, and Radibarrier thyroid shields. The thyroid shields were placed directly on the neck surface. The thyroid dose was measured using radiophoto-luminescence (RPL) detectors. Image quality was characterized by consistency of the Hounsfield unit (HU) on the areas of anterior, posterior and lateral of the neck phantom. Detailed evaluation of the image quality was employed by image subtraction.  https://www.selleckchem.com/CDK.html  It was found that the thyroid dose at the surface decreased with an increase of Pb percentage in the SR-Pb shield. The thyroid dose reduction was 34% for a Pb percentage of 5 wt%. The reduction of the dose using WP and Radibarrier were 36% and 67%, respectively. The dose reduction when using the WP and Radibarrier was higher than when using the SR-Pb 5 wt% thyroid shield. However the existence of artifact in the WP and the Radibarrier reduced the image quality, indicated by a significant change of HU, i.e. the increases of HU in the posterior area were 77% for the WP and 553% for the Radibarrier. The SR-Pb shield produced only a very small artifact, resulting in an increase of HU in the posterior area of only 9%. The SR-Pb shield is suitable in the daily clinical setting for thyroid dose reduction in CT examinations while maintaining image quality.The application of surgical suture-thread and the systemic analgesics regimens for pain control in the postoperative surgery remain the criterion standard. However, these medications have daunting adverse effects on the body's innate pain management system. To address this issue, we have developed a local analgesic-loaded suture system which could be efficiently used for surgical repair with localized sedation effect. The drug-loaded conventional suture has modified by adhesive poly-dopamine coating with the local anesthetic lidocaine. The surface modifications have been ascertained by FE-SEM imaging. The tensile strength of suture ensures required elasticity to use in surgical skin closure. In vitro drug release and the in vivo local analgesia was achieved one day after surgery and persisted approximately for one week in 80% of treated animals. Our pre-clinical results suggest that drug-loaded surgical thread may be an effective strategy for improving the overall outcome.