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The low-cost magnet less switched reluctance motor (SRM) speed-torque characteristics are perfectly suited for electric vehicles (EVs) drive performances are better than polyphase machines. The main drawback of SRM for EVs is torque ripple, it can be mitigated by optimal design aspects. In this study, to design SRM by changing the position of the stator and rotor pole, an increasing number of poles are investigated with optimum geometry. This paper presents the design procedure for EV applications of 250 kg mass, developed power of 2.9 kW and acceleration of 30 kmph. SRM rotor modification with two different cases of design of SRM with exterior rotor case with three-phase stator configuration 8/6, 10/6 and design of SRM with an interior rotor with three and four phases stator configuration 6/4, 8/6. The simulation was carried out using an electromagnet infolytica simulation package. The conditions of flux linkages, static torque, and rotor configurations are obtained using finite elements. FEA is used to verify the design of the SRM from an electrical standpoint. The results and performance analysis of the SRM drive were compared and analyzed for both cases. It is observed during the static and transient analysis that, the torque ripple in the 8/6 interior rotor design is lesser than in the exterior rotor design. The Interior rotor configuration 8/6 model may best be suited for EV’s high-speed application due to its low torque ripple characteristics compared to other models.

Summary: The switched reluctance motor (SRM) is a prominent electrical machine drive with low cost and good performance in different drive applications. This machine's main drawbacks are torque ripple and flux ripple. However, the existing SRM‐operated direct torque control (DTC) Voltage vectors (VVs) give high torque ripples due to improper sector division and minimum selection of VVs switching states. On the other hand, a two‐level hysteresis torque band can result in torque ripples. Therefore, this paper proposed DTC using 16 partitions, active small and large VVs, and a multilevel hysteresis torque band (MHTB) strategy to mitigate the torque ripple further. More active VVs (i.e., 16) are employed in the modified sector‐based switching tables, suppressing the torque ripples. The proposed strategy is verified and validated using MATLAB/Simulink. The detailed result discusses the response of torque, flux, and speed of SRM. The DTC‐operated SRM drive experimental results prove the effective minimization of torque ripples in the proposed DTC compared to the existing DTC. [ABSTRACT FROM AUTHOR]

Brachytherapy (BT) for locally advanced cervical cancer is vital for optimal outcomes. There is heterogeneity in brachytherapy treatment practice for cervical cancer across India. In an attempt to standardize various processes involved in cervical cancer brachytherapy, the expert members of the Indian Brachytherapy Society (IBS) developed a document related to radiation therapy treatment of cervical cancer with special emphasis on brachytherapy. The guidelines are based on high quality clinical evidence, expert opinion and consensus wherever evidence was lacking. The document provides a guide for external beam radiation and details of all the processes involved in high-dose-rate (HDR) brachytherapy including patient selection, preparation, principles and technique of BT applications, target and normal tissue definition, dose prescriptions, BT planning, reporting parameters, common complications of BT and their management, scope for research, etc. In summary, we present here practical tips and tricks, recording and reporting of cervical cancer brachytherapy, which can be implemented in various clinical environments and forms the basis of this report. [ABSTRACT FROM AUTHOR]

Background: Fatigue is one of the most common, ongoing symptoms reported by patients undergoing radiotherapy and has profound effects on the quality of life. Aims: This study attempts to identify the magnitude of fatigue and its implication on the quality of life during radiotherapy. Methods and Materials: A prospective study was conducted from March 2004 to September 2005, on 90 patients with histologically proven cancer, receiving radiotherapy. Pretreatment and weekly assessment of fatigue and QOL was done during radiation treatment using Brief Fatigue Inventory Scale and EORTC QLQ C30 respectively and repeated one month after completion of radiotherapy. All the scores were measured in the 0 to 100 scale. Statistical Methods Used: Trimean, SPSS 11.0 and Sysstat 8.0 were used for statistical analysis. Results: Fatigue was present in 87.8% of patients initially and increased gradually over the course of radiotherapy and peaked in the last week. However at follow up it was nearing the pretreatment level. There was significant reduction in the functional scores (P<0.001) of QOL (physical, role and emotional function), which returned to pretreatment level at follow up. In the seventh week impairment of cognitive function (P=0.059) was noted. Significant reduction of social function (P<0.001) at second week and global health status (P<0.001) at fifth week was noted while financial difficulty was seen from second week onwards. Conclusion: Fatigue is transiently increased by radiotherapy before reaching pretreatment level after few weeks of completion of radiotherapy. QOL is also affected by fatigue which follows the same pattern. [ABSTRACT FROM AUTHOR]

Two young male patients treated seven and four years back, for malignant glioma, returned with recurrence at the same site, with a World Health Organization (WHO) Performance Score of four and two. Both underwent resurgery and received postoperative reirradiation of 5040 cGy in 28 fractions and concurrent Temozolomide 75 mg/m² body surface area (BSA) daily, and one patient received additional adjuvant Temozolomide 250 mg (150 mg/m² BSA). Both patients tolerated the treatment well with 16 and 14 months follow-up from the time of recurrence. They were symptom-free, with normal physical function and good mental state, and resumed their respective jobs. [ABSTRACT FROM AUTHOR]

Intraocular metastatic tumor is the commonest intraocular malignancy in adults, with uveal tract the commonest site. In nearly 85% of cases the choroid is the afflicted site due to its vascularity. Breast and lung are the common primaries. In breast primaries, this could be the first metastatic disease. This condition should always be kept in mind in patients with visual symptoms. Fundus examination, ultrasonography and CT/MRI of the orbit help in diagnosis. Early recognition and timely treatment can save the visual function thus imparting good quality of life to the patient. External beam radiotherapy is a good local form of treatment. Hormone therapy in hormone receptor positive tumors can have additional benefits. Here we report a case of unilateral solitary choroid metastasis in a case of breast cancer treated with external beam radiotherapy. [ABSTRACT FROM AUTHOR]

Carcinoma of cervix is the most common cancer in developing countries. Majority of them present in locally advanced stages. A 36-year-old lady presented with bleeding and white discharge per vagina since four months, vomiting and reduced urine output since two weeks. Patient had an exophytic cervical growth. Investigation revealed elevated serum creatinine. Patient received single fraction radiation and underwent percutaneous nephrostomy. At one month follow-up, serum creatinine returned to almost normal level. Patient underwent bilateral ante grade stenting and completed concurrent chemoradiotherapy. In selected subsets of patients, aggressive management offered longer palliation and good quality of life. [ABSTRACT FROM AUTHOR]

Robust data on the spatial distribution of land degradation is important for resource conservation planning. Spatial land degradation status of India was mapped using multi-temporal Linear Imaging Self Scanning Sensor (LISS-III) data acquired from Resourcesat-1/2 during 2005-2006 and 2015-2016 under the Natural Resources Census programme of the Indian Space Research Organisation. Heads-up on-screen visual interpretation of multi-season satellite data was carried out, supported by digital elevation model and other historical maps available. Visual interpretation cues were developed and employed across various partner institutions to achieve consistency in mapping. The outputs were subjected to two-stage quality check. Results indicate that the total land degradation of India was 91.2 M ha (27.77% of the geographical extent of the country) during 2015-2016 against 91.3 M ha during 2005-2006. During the ten-year period, there was an overall decrease of around 0.1 M ha in degraded land. However, noticeable intra- and inter-class changes were observed in land degradation during the ten-year period. Major reclamation was noticed in sand dunes which were converted into crop lands by levelling them. Substantial decrease in severity and extent of salt-affected soils was noticed in Uttar Pradesh. [ABSTRACT FROM AUTHOR]