Common sources of radiations in a medical environment

Use of radiation is now a days so common in most of the tertiary care hospitals for diagnostic and therapeutic purpose. The ionizing radiation provides many benefits in both diagnostic as well as therapeutic interventions, but they are also potential harmful. Radiation risks, exposure and mitigation strategies should always be in mind while using to an individual (public, radiation worker, and patient) and the environment should not exceed the prescribed safe limits. Regular monitoring of hospital area and radiation workers is mandatory to assess the quality of radiation safety. This review article emphasis on radiation risks, exposure and prevention and treatment strategies

Measles rubella campaign - India’s journey from expanded program on immunization to measles elimination

Infectious diseases have always been a major cause of mortality and morbidity in children under 5 years of age and more so in developing countries like India. Steps toward control of these infectious diseases, especially the vaccine-preventable diseases, have been the priority of Indian Government. Smallpox was eliminated followed by polio and next target being measles. Although the journey has been tough, finally, the results are appreciable considering the large population and limited resources of the country. India has traveled a very long distance from the introduction of vaccination and acquiring country’s vaccine manufacturing to finally eliminating measles

Development of High-Performance Piezoelectric Micromachined Transducers for Near Ultrasound

Near-ultrasound refers to sound with frequencies just above the range of human hearing, from about 18 to 40 kHz. This band is rarely used for typical ultrasound applications and is ignored for all except the most demanding audio applications. We highlight the advantages of using this band and present a design study on the development of high-efficiency, resonant transducers for near-ultrasound. Piezoelectric Micromachined Ultrasound Transducers, or PMUTs, are MEMS resonators that are used to generate and receive ultrasound and acoustic waves. They are fabricated as multilayered diaphragms consisting of a passive structural layer coated with a piezoelectric material sandwiched between metal films. In this dissertation, we report the realization of a novel near-ultrasound PMUT system especially designed for Data-over-Sound (DoS) applications. This realization includes investigation of new transducer designs, innovation in fabrication processes, and a significant advance in acoustics and electronics integration. We use analytical and coupled finite element models of clamped circular plates with in-plane stresses to generate design maps for PMUTs. Residual tensile stresses generated during fabrication processes have the effect of stiffening the diaphragms and increasing their resonant frequencies. We experimentally estimate the magnitude of these stresses in sol-gel PZT-coated SOI wafers and fabricate transducers with dimensions optimized for near-ultrasound. The transducers are 50 times smaller and 20 times more efficient than conventional electrodynamic micro speakers in the near-ultrasound range. We then present a novel design for PMUTs with “bossed” diaphragms that allows further reduction in device footprint and power consumption while improving sensitivity and efficiency. The dimensions of the central boss structure are optimized using simulations. The fabricated devices are found to be up to 10 times smaller than conventional PMUTs for the same frequencies, and less sensitive to variations in residual stress. We have studied and optimized the effects of packaging and the acoustic environment on the performance of the transducers using finite element and boundary element acoustic simulations. The devices are packaged with 3D-printed acoustic resonators and horns designed to boost sensitivity, improve bandwidth, and widen the directivity of the transducers. The results of the simulations are experimentally verified by scanning the acoustic field of the transducers. The transducers are finally integrated into battery- and solar-powered DoS beacons and wireless sensor nodes, complete with a low-power microcontroller for modulation/demodulation, a low Q-current amplifier, a MEMS microphone, an acoustic resonator, and the near-ultrasound transducer — all in a compact package with a transmission range of up to 30 meters and a battery reserve of up to 4 weeks

Fibrodysplasia ossificans progressiva mimicking as fibroma with hypospadias

Fibrodysplasia ossificans progressiva (FOP) is a rare disease characterised by recurrent painful episodes of swelling in soft tissue and the occurrence of tumours in subcutaneous and muscular tissues. It causes severe disability and has an autosomal dominant penetration. We report a child with diffuse heterotopic ossification with characteristic hallux valgus of both the toes who was diagnosed inadvertently as multiple cutaneous fibromatosis before presenting to us. A very rare genetic syndrome was characterised on the basis of clinical manifestations and diagnosed in a peripheral tertiary institute. A diffuse soft-tissue enlargement is not always cancer and calcification therein may be FOP

Collective Transport of Robots: Coherent, Minimalist Multi-robot Leader-following

Abstract — We study the collective transport of robots (CTR) problem. A large number of commodity mobile robots are to be moved from one location to another by a single operator. Joysticking each one or carrying them physically is impractical. None of the robots are particularly sophisticated in their ability to plan or reason. Prior work on flocking and formation control has addressed the transport of a robot group that maintains its integrity by explicitly controlling coherence. We show how flocking emerges as a consequence of each robot contending for space near the human operator. A coherent flock can be made to follow a leader in this manner thereby solving the CTR problem. We also present the design of a hand-worn IMU-based gesture interface which allows the human operator to issue simple commands to the group. A preliminary experimental evaluation of the system shows robust CTR with different leade

DEVELOPMENT AND STUDY OF RETROFITTED STANDALONE SOLAR VAPOUR ABSORPTION REFRIGERATOR

Vapour Absorption Refrigeration Systems (VARS) are thermally activated cooling systems which can be run using waste process heat or solar energy. VARS are environment friendly and operates silently. This study attempts to convert a commercially available VARS into a standalone, portable solar-operated unit. Temperatures at the entry and exit of Generator, Rectifier, Condenser, Evaporator and Absorber in a commercially available VARS refrigeratorwere first obtained. The refrigerator is then retrofitted with a heating jacket. A hot fluid is passed through the jacket to replace the electric heating in the conventional refrigerator. The fluid is heated using a parabolic trough solar collector. Laboratory simulation of the collector was conducted using an immersion heating coil and data were recorded using commercial software LabVIEW 2010. Although temperatures obtained by the retrofitted system were equivalent to those produced by the electric heating, the time taken to attain the respective temperatures was too long to be technically viable. Sufficient wattage was also generated by the solar collector for attaining these temperatures. The heat flux generated by the present setup was not sufficient to activate the internal thermosiphon used to circulate the refrigerant and hence there was no cooling effect.Thus the use of a solar heating system on a VARS with a thermosiphon unit may not be a technically viable proposition to make it a standalone system