Elements Of X Ray Diffraction

A new generation of photothermal therapeutic agents based on biopolymer dopamine-melanin colloidal nanospheres is described. Benefitting from their naturally wide distribution in humans, dopamine-melanin colloidal nanospheres exhibit robust biocompatibility and biodegradability, and provide up to 40% photothermal conversion efficiency. After administration, they can efficiently damage tumors at low power density and short irradiation time without damaging healthy tissues.

Dopamine‐Melanin Colloidal Nanospheres: An Efficient Near‐Infrared Photothermal Therapeutic Agent for In Vivo Cancer Therapy

The arbitrary control of electromagnetic waves is a key aim of photonic research. Although, for example, the control of freely propagating waves (PWs) and surface waves (SWs) has separately become possible using transformation optics and metamaterials, a bridge linking both propagation types has not yet been found. Such a device has particular relevance given the many schemes of controlling electromagnetic waves at surfaces and interfaces, leading to trapped rainbows, lensing, beam bending, deflection, and even anomalous reflection/refraction. Here, we demonstrate theoretically and experimentally that a specific gradient-index meta-surface can convert a PW to a SW with nearly 100% efficiency. Distinct from conventional devices such as prism or grating couplers, the momentum mismatch between PW and SW is compensated by the reflection-phase gradient of the meta-surface, and a nearly perfect PW-SW conversion can happen for any incidence angle larger than a critical value. Experiments in the microwave region, including both far-field and near-field characterizations, are in excellent agreement with full-wave simulations. Our findings may pave the way for many applications, including high-efficiency surface plasmon couplers, anti-reflection surfaces, light absorbers, and so on.

http://www.physics.fudan.edu.cn/tps/people/lzhou/papers/84-NM%2011,426.pdf

Gradient-index meta-surfaces as a bridge linking propagating waves and surface waves

Magnetic nanomaterials for hyperthermia-based therapy and controlled drug delivery

In this paper, an overview of antenna design for passive radio frequency identification (RFID) tags is presented. We discuss various requirements of such designs, outline a generic design process including range measurement techniques and concentrate on one practical application: RFID tag for box tracking in warehouses. A loaded meander antenna design for this application is described and its various practical aspects such as sensitivity to fabrication process and box content are analyzed. Modeling and simulation results are also presented which are in good agreement with measurement data.

Antenna design for UHF RFID tags: a review and a practical application

I n t h e c o n t e x t o f t h i s "handbook" o f f e r i n g , a tmospher ics re fer to e lect romagnet ic s ignals that rad iate or are produced by l ightn ing and r e l a t e d e lec t r i ca l  d ischarge phenomena. Sometimes these  sign a l s a r e c a l l e d s f e r i c s and the i r ex i s tence was known s ince the ea r l y days o f r a d i o . The energy o f the observed signal may contain frequencies a l l t h e way from 1 h e r t z t o above  100 Mhz. Needless t o say, the presence o f such atmospheric energy i n .ou r env i ronment needs t o be  understood. I n s p i t e o f observat ional research spanning hal f a century, we r e a l l y do n o t have a c l e a r p i c t u r e o f what i s going on n o t t o mention  our  lack o f t h e o r e t i c a l i n s i g h t . More recent ly , inves t iga tors have  examined t h e s u b j e c t i n the contex t o f the e lec t romagnet ic s igna ls tha t can be produced ind i rect ly f rom the prompt gama radiat ion associated wi th nuc lear detonat ions.

http://ieeexplore.ieee.org/iel6/8233/25559/01141474.pdf

Antenna theory

Thermal therapy is widely known and electromagnetic (EM) energy, ultrasonic waves, and other thermal-conduction-based devices have been used as heating sources. In particular, advances in EM technology have paved the way for promising trends in thermotherapeutical applications such as oncology, physiotherapy, urology, cardiology, ophthalmology, and in other areas of medicine as well. This series of articles is generally written for oncologists, cancer researchers, medical students, biomedical researchers, clinicians, and others who have an interest in this topic. This article reviews key processes and developments in thermal therapy with emphasis on two techniques, namely, hyperthermia [including long-term low-temperature hyperthermia (40-41 degrees C for 6-72 hr), moderate-temperature hyperthermia (42-45 degrees C for 15-60 min), and thermal ablation, or high-temperature hyperthermia (> 50 degrees C for > 4-6 min)]. The article will also provide an overview of a wide range of possible mechanisms and biological effects of heat. This information will be discussed in light of what is known about the degree of temperature rise that is expected from various sources of energy. The review concludes with an evaluation of human exposure risk to EM energy or the corresponding heat, trends in equipment development, and future research directions.

/pdf/thermal-therapy-part-1-an-introduction-to-thermal-therapy-47hu5n34ar.pdf

Thermal therapy, part 1: an introduction to thermal therapy.

Hyperthermia, the procedure of raising the temperature of a part of or the whole body above normal for a defined period of time, is applied alone or as an adjunctive with various established cancer treatment modalities such as radiotherapy and chemotherapy. Clinical hyperthermia falls into three broad categories, namely, (1) localized hyperthermia, (2) regional hyperthermia, and (3) whole-body hyperthermia (WBH). Because of the various problems associated with each type of treatment, different heating techniques have evolved. In this article, background information on the biological rationale and current status of technologies concerning heating equipment for the application of hyperthermia to human cancer treatment are provided. The results of combinations of other modalities such as radiotherapy or chemotherapy with hyperthermia as a new treatment strategy are summarized. The article concludes with a discussion of challenges and opportunities for the future.

http://oncothermia.ru/d/150191/d/habash_thermal_therapy,_part_2.pdf

Thermal therapy, part 2: hyperthermia techniques.

In this paper, circular and hexagonal array geometries for smart antenna applications are compared. Uniform circular (UCA) and hexagonal arrays (UHA) with 18 half-wave dipole elements are examined; also planar (2 concentric rings of radiators) uniform circular (PUCA) and hexagonal arrays (PUHA) are considered. The effect of rotating the outer ring of the PUCA is studied. In our analysis, the method of moments is used to compute the response of the uniform circular and hexagonal dipole arrays in a mutual coupling environment. The particle swarm optimization (PSO) algorithm is used to optimize the complex excitations, amplitudes and phases, of the adaptive arrays elements for beamforming.

/pdf/a-comparison-between-circular-and-hexagonal-array-geometries-nehreklzqq.pdf

A Comparison Between Circular and Hexagonal Array Geometries for Smart Antenna Systems Using Particle Swarm Optimization Algorithm

Ablative treatments are gaining increasing attention as an alternative to standard surgical therapies, especially for patients with contraindication or those who refuse open surgery. Thermal ablation is used in clinical applications mainly for treating heart arrhythmias, benign prostate hyperplasia, and nonoperable liver tumors; there is also increasing application to other organ sites, including the kidney, lung, and brain. Potential benefits of thermal ablation include reduced morbidity and mortality in comparison with standard surgical resection and the ability to treat nonsurgical patients. The purpose of this review is to outline and discuss the engineering principles and biological responses by which thermal ablation techniques can provide elevation of temperature in organs within the human body. Because of the individual problems associated with each type of treatment, a wide range of ablation techniques have evolved including cryoablation as well as ultrasound, radiofrequency (RF), microwave, and laser ablation. Aspects of each ablation technique, including mechanisms of action, equipment required, selection of eligible patients, treatment techniques, and patient outcomes are presented, along with a discussion of limitations of the techniques and future research directions.

Rajeev Bansal

Papers

Antenna theory

Thermal therapy, part 1: an introduction to thermal therapy.

Thermal therapy, part 2: hyperthermia techniques.

A Comparison Between Circular and Hexagonal Array Geometries for Smart Antenna Systems Using Particle Swarm Optimization Algorithm

Thermal Therapy, Part III: Ablation Techniques