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BACKGROUND Varicose veins in lower limbs cause a lot of morbidity in humans and a significant financial burden on the health care system. Varicose veins do not threaten life and are seldom disabling. A high prevalence of varicose veins has been documented in India. Hence, we decided to conduct a study on the demographic factors and clinical profile of varicose veins in adults. METHODS It is an observational study. 200 patients aged>12 years with varicose veins of the lower limbs were studied. Statistical Analysis was performed with help of Epi Info (TM) 7.2.2.2. RESULTS 200 patients were studied, of whom 87.5 % were aged ≥ 35 Years; 74.5 % were males, 25.5 % were females; 70.0 % had normal BMI, 75.9 % were from the urban area, 11.5 % had a family history of varicose veins, 10.5 % had addictions, 57.0 % had a duration of standing >5 hours. 62.0 % were examined at OPD, 82.5 % were unilateral and 17.5 % bilateral. The heights of the patients were significantly higher than the normal height of average Indians. The most common symptoms were varicosities and pain present in 80.85 % and 71.49 % of cases respectively. Out of 235 lower limbs, 48.93 % had the involvement of only GSV, 18.72 % only SSV, 32.35 % both; incompetent saphenofemoral junction was present in 67.24 % clinically and 74.89 % radiologically; 150 mid-thigh, 62 above-knee, 55 below-knee, 106 calf, 72 ankle perforators were incompetent clinically; 165 mid-thigh, 80 above-knee, 65 below-knee, 118 calf, 95 ankle perforators were incompetent radiologically; 65 (27.66 %) belonged to C2 class, 60 (25.53 %) to C4 class and 60 (25.53 %) to C6 class. CONCLUSIONS Age > 35 years, male gender, tall height, and prolonged standing are associated with increased risk of varicose veins whereas obesity, family history and addictions do not have any association. Varicose veins are more commonly unilateral with the involvement of a great saphenous vein. Colour Doppler is better at detecting incompetent perforators compared to clinical assessment.

Validation of synthetic storm technique (SST) has been done for prediction of attenuation due to rain over a hilly, high-rainfall, tropical location, Shillong (25°N, 91°E), India. In this letter, considering one year of rain attenuation and rain rate data shows that SST predicted attenuation overestimates while comparing the available experimental result. Storm speed has been found to have no significant effect on the attenuation prediction by SST. Second-order rain attenuation prediction, i.e., prediction of fade slope, has also been studied. Fade slope is found to have been overestimated by SST for all categories of rain events at 20.2- and 30.3-GHz frequency. Exceedance plot of fade duration by SST shows an overestimation for higher frequency and underestimation for lower frequency.

The effect of climate change on precipitation pattern is emerging out as a serious global challenge. However, the quantification and assessment of the climate change effect on precipitation are a challenging issue given the spatio-temporal inhomogeneity of rainfall. Previous studies mostly used only rain intensity information for the identification of climate change signature by selecting homogeneous rain regions. Rain climatology, however, has several other important characteristics like occurrence of multiple rain type, occurrence of extreme rain events and their spatial distribution. The present study provides a novel approach to combine satellite data with ground measurements for addressing this issue. In this study, the Indian subcontinent has been divided into homogeneous regions based on six different rain features, obtained from ground observations and TRMM satellite measurements of 12 years, using K-medoid clustering technique. The rain features showed distinguishable patterns in the resulting nine homogeneous rain zones and distinct behavioural patterns in the inter-relationships between the various rain features. To verify the consistency of the proposed regionalization, the recent changes in mean monsoon rain rates are then studied using 40 years of rain gauge measurements for these regions. Increasing trends in monsoon rain are observed in two homogeneous regions whereas five of them have shown decreasing signature of rain intensity. Although the present study focused only on monsoon rain over India, the results indicate the suitability of the proposed method as an efficient technique of identifying homogeneous region for other seasons and locations as well.

Satellite signal at the Ka -band is measured at a hilly, high rain fall region, Umiam, Shillong (25.6768° N, 91.9270 °E) for three years using GSAT 14 satellite. Scintillation has been extracted using a Butterworth filter of tenth order and 0.025 Hz cutoff frequency. Experimental results are then compared with the existing ITU-R scintillation model, Karasawa model, Van de Kamp model, and Ortgies-T model. Deviation of the above-mentioned models from measured data is then studied. The ITU-R model is found to be the best while Ortgies-T is found to be the worst performer over this region. New parameterization for the ITU-R scintillation model for the Ka -band is further proposed for this region based on one year of measured data and validated against other two years of data of 20.2 GHz. The results indicate the improved performance of the proposed model with a very high correlation value.

Background: Colorectal cancer surgery has undergone a continuous evolution of techniques and technologies with the aim of improving oncological outcome and the quality of life. Methods: Using a computer-based randomization patients were divided into two groups. One group underwent laparoscopic surgery (n=20) while the other open surgery (n=20). Results: rd th th th Most common age group affected was in the 3 and 4 decade of life followed by the 5 and 6 decade with a male: female ratio of 1.1:1. The mean operating time was longer in laparoscopic group (218.0±28 mins vs. 191±25 mins in open group) but the intra-operative blood loss was signicantly less in the laparoscopic group (46.2±8 ml) than the open group (107±11 ml). Post-operative complications like wound infection were signicantly lower in the laparoscopic group (zero patient vs. six patients in open group). Conclusion: With proper training and expertise laparoscopic surgery is advantageous over open surgery in colorectal malignancies.

Propagation impairment due to rain is one of the most critical considerations for satellite communication (Satcom) links above 10 GHz. The existing studies at tropical and equatorial regions are mostly focused on rain attenuation characteristics derived from rainfall characteristics, which may not be adequate to represent actual rain attenuation characteristics. The experimental studies on the same topic are very scattered and limited over these regions. Consolidating experimental results can provide a good background for rain attenuation studies over these regions and will be helpful to validate new models as well as devise new strategies to combat high fade condition. In this article, we attempt to review and summarize the performance of different rain attenuation models validated against satellite signal measurements at tropical and equatorial locations. This will serve as a benchmark for understanding the rain attenuation characteristics over this part of the globe.

A family of three water-soluble half-sandwich arene-ruthenium complexes, depicted as C1 -C3 , having the general formula [Ru(p-cymene)(L)Cl]Cl has been synthesized, where L represents (1H-benzo[d]imidazol-2-yl)guanidine (L1 ) or (benzo[d]oxazol-2-yl)guanidine (L2 ) or (benzo[d]thiazol-2-yl)guanidine (L3 ). The crystal structure of complex C3 has been determined. The complexes show several absorption bands in the visible and ultraviolet regions, and they also show prominent emission in the visible region while excited near 400 nm. Studies on the interaction of ligands L1 -L3 and complexes C1 -C3 with calf thymus DNA reveal that the complexes are better DNA binders than the ligands, which is attributable to the imposed planarity of the ruthenium-bound guanidine-based ligand, enabling it to serve as a better intercalator. Molecular docking studies show that the complexes effectively bind with DNA through electrostatic and H-bonding interactions and partial intercalation of the guanidine-based ligands. Cytotoxicity studies carried out on two carcinoma cell lines (PC3 and A549) and on two non-cancer cell lines (BPH1 and WI-38) show a marked improvement in antitumor activity owing to complex formation, which is attributed to improvement in cellular uptake on complex formation. The C1 complex is found to exhibit the most prominent activity against the PC3 cell line. Inclusion of the guanidine-based ligands in the half-sandwich ruthenium-arene complexes is found to be effective for displaying selective cytotoxicity to cancer cells and also for convenient tracing of the complexes in cells due to their prominent emissive nature.

The treatment of malignant cells that are deficient in oxygen due to the insufficient flow of blood is often seen as a major hindrance in radiotherapy. Such cells become radio-resistant because molecular oxygen, the natural and best radio-sensitizer, is depleted. Hence, to compensate this deficiency in oxygen, there is a need for agents that enhance radiation-induced damage of cells (radio-sensitizers) in a manner that normal cells are least affected. Simultaneously, agents capable of showing activity under hypoxic conditions are known as hypoxic cytotoxins that selectively and preferably destroy cells under hypoxic environments. 5-Nitroimidazoles fit both definitions. Their efficiency is based on their ability to generate the nitro radical anion that interacts with the strands of DNA within cells, either damaging or modifying them, leading to cell death. 5-Nitroimidazoles are important radio-pharmaceuticals (radio-sensitizers) in cancer-related treatments where the nitro radical anion has an important role. Since its generation leads to neurotoxic side effects that may be controlled through metal complex formation, this study looks at the possibility of two monomeric complexes of Ornidazole [1-chloro-3-(2-methyl-5-nitro-1H-imidazole-1-yl)propan-2-ol] with CuII and ZnII to be better radio-sensitizers and/or hypoxic cytotoxins than Ornidazole. The study reveals that although there is a decrease in nitro radical anion formation by complexes, such a decrease does not hamper their radio-sensitizing ability. Nucleic acid bases (thymine, cytosine, and adenine) or calf thymus DNA used as targets were irradiated with 60Co γ rays either in the absence or presence of Ornidazole and its monomeric complexes. Radiation-induced damage of nucleic acid bases was followed by high-performance liquid chromatography (HPLC), and modification of calf thymus DNA was followed by ethidium bromide fluorescence. Studies indicate that the complexes were better in performance than Ornidazole. CuII-ornidazole was significantly better than either Ornidazole or ZnII-ornidazole, which is attributed to certain special features of the CuII complex; aspects like having a stable lower oxidation state enable it to participate in Fenton reactions that actively influence radio-sensitization and the ability of the complex to bind effectively to DNA.

Curcumin is an important molecule with a plethora of pharmacological activities and therapeutic potentials. Despite its efficacy, it remained a potential drug candidate owing to hydrolytic instability and poor aqueous solubility. To overcome the limitations related to low solubility, low bioavailability, and the fact that curcumin is never present in solution as a "single unit", its complex was prepared with MnII with the idea that binding to a metal ion might help to resolve these issues. The complex was characterized by elemental and spectral analysis. The structure of the complex was determined by density functional theory calculations. The complex was stable at physiological buffer conditions, unlike curcumin. It did not have any detrimental effect on mammalian cells. There was a significant enhancement in the antibacterial activity of the complex compared to curcumin against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. It showed a strong affinity for deoxyribonucleic acid (DNA) evident from a high binding constant value with calf thymus DNA and also from the retarded electrophoretic mobility of bacterial plasmid DNA. The complex showed "superoxide dismutase-like" activity leading to the generation of reactive oxygen species (ROS). The complex caused bacterial membrane perturbation evident from calcein leakage assay, which was further corroborated by scanning and transmission electron microscopic experiments. Overall, the present study shows improved stability and antibacterial potency of a nontoxic complex over curcumin. Its multitargeting mode of action such as ROS-production, effective binding with DNA, and permeabilization of bacterial membrane together allows it to be an effective antibacterial agent that could be taken further for therapeutic use against bacterial infections.

The presence of coronal holes in solar disk plays an important role in influencing the space weather and generation of the solar wind. As such there lies a requirement in proper study and prediction of coronal holes occurs in the solar disk. This, in turn, arises the necessity of detection of coronal holes present in the solar disk. In this work, a Hough transformed inspired fuzzy-energy simulated dual contours-based segmentation technique has been proposed for the detection and extraction of holes in solar disk. In the proposed method Hough transform has been induced to initialize the contour for the contour-based method of segmentation. In the algorithm, two contours (active and static) have been initiated and made to evolve based on the energy function by incorporating the gray-scale intensity. Here in the work one contour is made to deform its shape while the other contour is kept static for the coronal holes detection purpose. The experiment has been carried out on few benchmark datasets and the corresponding outcomes have been compared with the results of other existing algorithms. The comparison results highlight the performance of the proposed technique in detection of coronal holes in solar disk.

Navigation satellites provide a good opportunity to monitor both ionospheric and tropospheric conditions by using propagation delays in the L-band signal. However, the availability of S-band frequency in the Indian Regional Navigation Satellite System, Navigation with Indian Constellation (NavIC), provides a unique opportunity to utilize signal strength for monitoring thunderstorms. This article, for the first time, demonstrates that NavIC satellite signal strength measurements can be used to detect thunderstorms. A dynamic time warping technique has been used to detect the presence of thunderstorm cloud systems. The method has been tested with several case studies in Kolkata using one-year measurements. The results indicate suitability of such techniques for monitoring and forecasting of thunderstorms using a navigation satellite.

This paper emphasizes on NavIC's performance in ionospheric studies over the Indian subcontinent region. The study is performed using data of one year (2017-18) at IIT Indore, a location near the northern crest of Equatorial Ionization Anomaly (EIA). It has been observed that even without the individual error corrections, the results are within $\pm20\%$ of NavIC VTEC estimates observed over the 1\ensuremath{^{\circ}} x 1\ensuremath{^{\circ}} grid of IPP surrounding the GPS VTEC estimates for most of the time. Additionally, ionospheric response during two distinct geomagnetic storms (September 08 and 28, 2017) at the same location and other IGS stations covering the Indian subcontinent using both GPS and NavIC has also been presented. This analysis revealed similar variations in TEC during the geomagnetic storms of September 2017, indicating the suitability of NavIC to study space weather events along with the ionospheric studies over the Indian subcontinent., Comment: 38 Pages, 16 Figures, Accepted for publication in Advances in Space Research

To effectively interpret the fluid flow dynamics in the molten metal pool, a numerical model was established. The moving repetitive Gaussian laser pulse is irradiated in the work piece. The consideration of laser scanning speed makes the transport phenomena complex. The continuity and momentum equations are solved to get the flow velocity of the molten metal in the melt pool. The energy equation is solved to know the temperature field in the work piece. The algebraic equations obtained after discretization of the governing equations by Finite Volume Method (FVM) are then solved by the Tri Diagonal Matrix Method. Enthalpy-porosity technique is used to capture the position of the melt front which determines the shape of the melt pool. Marangoni convection is considered to know its effect on the shape of the melt pool. The surface tension coefficient is taken as both positive and negative value while calculating the Marangoni force. The two possible cases will cause the Marangoni force to distort the flow dynamics in the melt pool . It's dominance over the buoyancy force in controlling the melt pool shape is focused in the present study. Further, the present model will present an insight to the consequences of laser scanning velocity over the melt pool dimensions and shape.

Formation of nitro radical anion (-NO

This article implements a Convolutional Neural Network (CNN)-based deep-learning model for solar-wind prediction. Images from the Atmospheric Imaging Assembly (AIA) at 193 A wavelength are used for training. Solar-wind speed is taken from the Advanced Composition Explorer (ACE) located at the Lagrangian L1 point. The proposed CNN architecture is designed from scratch for training with four years’ data. The solar-wind has been ballistically traced back to the Sun assuming a constant speed during propagation, to obtain the corresponding coronal-intensity data from AIA images. This forecasting scheme can predict the solar-wind speed well with a RMSE of 76.3 ± 1.87 km s−1 and an overall correlation coefficient of 0.57 ± 0.02 for the year 2018, while significantly outperforming benchmark models. The threat score for the model is around 0.46 in identifying the HSEs with zero false alarms.

A monomeric complex of ZnII with ornidazole [Zn(Onz)2Cl2] decreases formation of the nitro-radical anion (R–NO2˙−), and this is realized by recording it in an enzyme assay using xanthine oxidase, which is a model nitro-reductase. Although the formation of R–NO2˙− is essential for drug action, as it is also associated with neurotoxic side effects, it is imperative to control its generation in order to avoid excess presence. With a decrease in R–NO2˙−, while the neurotoxic side effects should decrease, it can be expected that a compromise with regard to therapeutic efficacy will be seen since the complex will be less active in the free radical pathway. Since R–NO2˙− is crucial for the functioning of 5-nitroimidazoles, we attempted to find out if its biological activity is affected in any way in our effort to control its formation. For this purpose, Entamoeba histolytica (HM1:IMS Strain) was chosen as a biological target to realize the performance of the complex with respect to ornidazole (R–NO2). The experiments revealed that the complex not only compares well with ornidazole, but in fact, under longer exposure times, it also performs better than it. This efficacy of the complex was seen despite a decrease in R–NO2˙−, as identified by an enzyme assay, and this was probably due to certain attributes of the complex formation that are not known for ornidazole. These attributes outweigh any loss in efficacy in the free radical pathway following complex formation. This is certainly an advantage of complex formation and helps to improve the therapeutic index. This study has attempted to look at some of the possible reasons why the complex performs better than ornidazole. One reason is its ability to bind to DNA better than ornidazole does, and this can be understood by following the interaction of ornidazole and its Zn(II) complex with calf-thymus DNA using cyclic voltammetry. Therefore, this study showed that despite a decrease in R–NO2˙−, the complex does not compromise its efficacy, and this was examined using a biological target. In addition, the complex is likely to have less toxic side effects on the host of the disease-causing microbes.

Noise leads to the ambiguity in regions of interest detection by corrupting the pixel information and is a vital problem in image processing domain. A novel hybrid technique based on fuzzy filtering and fuzzy thresholding is proposed here to extract the object regions accurately in presence of Gaussian noises. The proposed method is automated, does not need any parameter tuning as well does not need prior knowledge of the image or noise. An asymmetrical triangular fuzzy filter with median center coupled with a thresholding based on fuzziness minimization technique are implemented for this purpose. The fuzzy thresholding technique helps to classify the pixels with low signal-to-noise ratio (SNR) caused either due to noise or by the application of noise removal process. The proposed technique is applied in benchmark images corrupted by noises and are compared with some of the popular algorithms of object detection. The results indicate that the proposed method has superior performance in terms of peak signal-to-noise ratio (PSNR) and mean square error (MSE) value for images corrupted with Gaussian noises with standard deviation upto 1.5.

There is enough proof to believe that free-radical intermediates of anthracycline based anticancer agents are involved in different stages of drug action. Subtle therapeutic differences observed in the actions of different anthracyclines largely influence the mechanism of action of the drugs that distinguish one member from another. Redox properties control biological responses related either to the one-electron quinone/semiquinone couple or the two-electron quinone/quinone-dianion couple. Comproportionation also leads to generation of semiquinone. Hence, whatever the form of reduction of the quinone moiety, a substantial amount of semiquinone is eventually formed in the system. Immediately after formation, there is competition between natural radical-decay pathways and one-electron transfer reactions that generate the superoxide-radical anion. Prototropic properties control rate of radical decay while redox properties control rate of electron transfer to molecular oxygen. In aerated medium, semiquinone-radical anion and superoxide-radical anion co-exist while in de-aerated medium semiquinone-radical anion predominates. All the radicals are damaging to the biological system. Through this study, attempt was made to detect changes induced by the radicals on pyrimidine based nucleic acid bases and calf thymus DNA in aerated and de-aerated (Ar saturated) medium to know the mechanism by which Emodin, its CuII/MnII complexes might affect DNA. Semiquinone-radical anion was generated electrochemically maintaining a glassy carbon electrode at the first reduction potential of each compound. Since the chosen compound (Emodin), its complexes are analogues of anthracyclines, findings on them can be extrapolated to understand the differences in anticancer activity or of adverse drug reactions reported in an innumerable number of clinical studies related to anthracyclines where the difference in structure of different members is due to differences in the relative positioning of hydroxy groups on the hydroxy-9, 10-anthraquinone moiety of anthracyclines. The study helps to realize action of compounds of this class as anticancer agents.

Intense geomagnetic storms can have a strong impact on the signals (termed as ionospheric scintillations) emitted by any global navigation satellite system (GNSS). The paper reports the first ever scintillations at Indore region on the NavIC signals due to impact of the intense geomagnetic storm event reported on September 8, 2017 at 01:51 and 13:04 UT. The variation of the planetary indices as well as the DST index which dropped to value of −124 nT on September 8, 2017 indicates the occurrence of an intense geomagnetic storm on September 8, 2017. The observations presented are carried out at Indore, which is located at the equatorial anomaly crest. The S4 index measurements of co-located GNSS receiver showed values ≥0.5 on the disturbed day between 15 and 18 UT. The analysis presented clearly signifies the degradation of carrier–noise measurements of NavIC L5 signal during the same time, which in turn affected the positional accuracy of NavIC, an important consideration for performance.

Detection of coronal holes (CHs) in the solar disk is one of the important tasks in the domain of astronomy. In this work, a technique based on image segmentation has been used for the detection of the CHs in the solar disk image. Here in the work, the task of image segmentation has been carried out using fast fuzzy c-means algorithm (FFCM). In the work, modified classical fuzzy c-means clustering technique has been induced for the segmentation of solar-disk image and detection of CHs in the image. For the purpose, the histogram of image intensities has been taken into account in order to faster the clustering and segmentation process. The output of the proposed algorithm has been compared visually with other existing technique of CHs detection in order to validate the capability of the proposed technique.