Three-dimensional analysis of the surface mode supported in \v{C}erenkov and Smith-Purcell free-electron lasers

In \v{C}erenkov and Smith-Purcell free-electron lasers (FELs), a resonant interaction between the electron beam and the co-propagating surface mode can produce copious amount of coherent terahertz (THz) radiation. We perform a three-dimensional (3D) analysis of the surface mode, taking the effect of attenuation into account, and set up 3D Maxwell-Lorentz equations for both these systems. Based on this analysis, we determine the requirements on the electron beam parameters, i.e., beam emittance, beam size and beam current for the successful operation of a \v{C}erenkov FEL

Orbit Classification of asteroids using implementation of radial Basis Function on Support Vector Machines

This research paper focuses on the implementation of radial Basis Function (RBF) Support Vector Machines (SVM) for classifying asteroid orbits. Asteroids are important astronomical objects, and their orbits play a crucial role in understanding the dynamics of the solar system. The International Astronomical Union maintains data archives that provide a playground to experiment with various machine-learning techniques. In this study, we explore the application of RBF SVM algorithm to classify asteroids. The results show that the RBF SVM algorithm provides a good efficiency and accuracy to the dataset. We also analyze the impact of various parameters on the performance of the RBF SVM algorithm and present the optimal parameter settings. Our study highlights the importance of using machine learning techniques for classifying asteroid orbits and the effectiveness of the RBF SVM algorithm in this regard.Comment: 15 pages, 8 figures, 3 table

Abnormal meiosis in hexaploid Setaria verticillata

This article does not have an abstract

Dyanmics of falling raindrops

Studying water droplets is a rich lesson in fields of fluid dynamics, nonlinear systems, and differential equations. Understanding various physical aspects of raindrops can help us in understanding drop dynamics, rainfall density estimation, size distributions which can be grant insights in the fields of meteorology, hydrology, and climate science. This work identifies the real world significance in developing more accurate atmospheric attenuation correction algorithms that could potentially overcome the scattering effect of rain on radio and micro wave communication. This works presents and aims to compile some historical work which focuses on the influence of surface tension in the droplet nucleation and formation, raindrop oscillation, burst cycles, and transformation into parachute-like shapes before fragmentation. The interplay between surface tension and air resistance in raindrop dynamics is also explored.Comment: 15 pages, 2 figure

Pulmonary hypertension leading to right heart failure in a patient with iga gammopathy

Amyloidosis is a rare disorder characterized by the deposition of amorphous, extracellular, insoluble fibrillar protein in various tissues of the body. Pulmonary hypertension usually occurs in the last stages of the disease with co-existing left ventricular failure. Amyloidosis causing pulmonary hypertension in a patient with no evidence of left ventricular failure is rarely mentioned in literature. Here, we present a patient with IgA gammopathy presenting with pulmonary hypertension leading to progressive right heart failure and death

A study of ultrasonographic transcerebellar diameter in assessment of fetal gestational age

Background: Accurate assessment of gestational age is of paramount importance for the clinician to impart holistic antenatal care and is also essential prerequisite to plan the various clinical tests and interventions. Ultrasound (USG) morphometric measurements of fetal parts have been used to assess gestational age of the fetus with improved accuracy. The present study aims at comparing the ultrasonographic measurement of transverse cerebellar diameter (TCD) with other previously established fetal ultrasound biometric parameters, to study its role in patients of suspected intrauterine growth retardation (IUGR) and to study ultrasonographic appearance of fetal cerebellum with advancing gestational age.Methods: A total of 153 pregnant women who were referred for antenatal ultrasound examination were divided into two groups-Group I had 137 healthy pregnant women with normal fetuses between 14-40 weeks of gestation and Group II had 16 patients suspected to have IUGR clinically.Results: In group I, there was a curvilinear relationship between TCD and BPD, TCD and HC, TCD and AC and TCD and FL with correlation coefficients being 0.9810, 0.9181, 0.9649 and 0.9513 respectively. In group II, TCD correlated with gestational age predicted by last menstrual period. The remaining biometric parameters in group-II predicted a fetus of much earlier grade. The study findings also suggested a gradual and steady change in ultrasonographic appearances of cerebellum with advancing gestation.Conclusions: Ultrasonographic measurement of TCD shows excellent correlation with advancing gestational age and with other previously established biometric parameters. TCD can serve as an independent and reliable indicator of gestational age and a standard against which aberrations in fetal growth may be compared

Simple vs ugly adnexal lesions: is ultrasonography alone good enough?

Background: Ultrasound (USG) is easily available and effective imaging modality for adnexal lesions. A simple looking lesion on ultrasound is usually benign and an ugly looking adnexal lesion is either benign or malignant. This study aims to evaluate the varied appearance of simple and ugly benign adnexal lesions on USG and to find out any additional role of colour Doppler in such suspected benign lesions. The confirmation of diagnosis was done either by follow up appearance of lesions on USG or by histopathological evaluation.Methods: A total of 55 consecutive female patients with age between 18 to 50 years were enrolled in this prospective cross sectional study. USG and colour Doppler for all the lesions were done. The patients found to have malignant lesions on histopathological examination, were later excluded from the analysis. Follow up USG was done for all the cases. Those cases wherein there was no resolution of lesions even after 08 weeks, were given an option to undergo laparoscopy as next management step.Results: Out of 50 benign adnexal masses, 88% masses were ovarian in origin and 12% were tubal masses. Ovarian masses included hemorrhagic cysts, endometriosis, simple cysts, serous cystadenomas and ovarian dermoid. All extra-ovarian masses were hydrosalpinx. Colour Doppler did not add any additional finding. Some of the patients underwent diagnostic laparoscopy followed by excision of masses in majority of them.Conclusions: Benign adnexal lesions can have varied appearance ranging from simple to ugly on USG. Ultrasonographic features of benign lesions on USG can be appreciated very well even without further use of colour Doppler or cross sectional imaging. Follow up USG remains key modality for benign adnexal masses in absence of MRI