Weed Plant Detection

Knowledge about the distribution of weeds in the field is a prerequisite for site-specific treatment. Optical sensors make it possible to detect varying weed densities and species, which can be mapped using GPS data. The weeds are extracted from images using image processing and described by shape features. A classification based on the features reveals the type and number of weeds per image. For the classification only a maximum of 16 features out of the 81 computed ones are used. Features are used, which enable an optimal distinction of the weed classes. The selection can be done using data mining algorithms, which rate the discriminance of the features of prototypes. If no prototypes are available, clustering algorithms can be used to automatically generate clusters. In a next step weed classes can be assigned to the clusters. Such a procedure aids to select prototypes, which is done manually. Classes can be identified, that are distinct in the feature space or which are overlapping and therefore not well separable. Clustering can be used in some, less complex cases to establish an automatic procedure for the classification. Weed maps are generated using the system. These are compared to the result of a manual weed sampling

Polypharmacy and predictors of high level polypharmacy in patients with diabetic nephropathy in a tertiary care hospital

Background: Diabetic Nephropathy (DN) is the leading cause of end-stage renal disease. Polypharmacy is common in DN as pharmacotherapy is complex with multimorbidity. The objectives of the study are to assess the prevalence and patterns of polypharmacy and to determine the predictors of high-level polypharmacy among patients with diabetic nephropathy in a tertiary care hospital.Methods: A prospective observational study was conducted among adult patients with DN visiting nephrology outpatient department (March 2015 to August 2016). Data on demography, disease characteristics, and treatments were collected. Baseline data were summarized using descriptive statistics. Categorical variables and predictors of polypharmacy were analysed using Chi-square tests and multivariate logistic regression respectively.Results: Mean age of patients was 58.14±10.44 years with male preponderance (72.7%). A majority of patients had comorbidities (76%). Hypertension was the most common co-morbidity (98.7%). Majority (64%) were in DN stage 4-5 and 58% of patients were undergoing hemodialysis. Mean number of drugs prescribed was 9.25±2.5. Anti-hypertensives (95.3%) were the major drug class prescribed. Polypharmacy (>5 drugs) was noticed in 95.3% patients and high-level polypharmacy (>10 drugs) in 46.7%. Presence of ≥3 comorbidities is a significant predictor of high-level polypharmacy (OR-1.414: 95% CI (1.008, 1.982), p=0.045).Conclusions: Polypharmacy was noticed in a majority of patients with high level polypharmacy in more than one third of patients with DN. Presence of ≥3 comorbidities were found to be significant predictor of high-level polypharmacy

Electromechanical effect in cholesteric liquid crystals with fixed boundary conditions

We describe a number of experiments to demonstrate the electromechanical effect in cholesteric liquid crystals. The Lehmann rotation phenomenon of drops with stress free boundary conditions is the most convincing effect produced by this coupling. In samples with fixed boundary conditions, the cross coupling produces a distortion of the profile of the azimuthal angles of the director. We have used a conoscopic technique to demonstrate this distortion in thick samples containing negative dielectric anisotropy materials. A strong linear electrooptic effect of electromechanical origin is produced in materials with a weak positive dielectric anisotropy. We provide an evidence that a twisted nematic cell without any chiral molecules also exhibits the electromechanical effect, due to the macroscopic chirality of the medium in such a cell

Genetic diversity study in tropical carrot (Daucus carota L.)

Genetic diversity study was conducted at ICAR- Indian institute of Horticultural Research, Bengaluru during 2018-19. In this study, 80 accessions were evaluated for 16 yield and yield attributing traits. The Mahalanobis’ D2 analysis grouped these accessions into seven clusters. Cluster I was the largest with 69 genotypes followed by cluster III comprising six genotypes while, the clusters II, IV, V, VI and VII contained one genotype each. Among the traits studied, yield contributed maximum (38.04 %) towards diversity, followed by root weight (26.58%), root color (9.18%) and plant height (6.7%). As far as root weight (g) [d1], leaf weight (g), root weight (g), number of leaves, TSS(°Brix), leaf weight (g), root diameter (mm), core diameter (mm), and root cracking are concerned, they contributed 3.45, 2.09, 1.77, 1.71, 1.55, 1.52, 1.46, 1.33, 1.01 and 0.82 percent respectively. Diversity analysis has given an indication about the genetic variation among the carrot accessions which will prove useful in selection of diverse parents in crop improvement programme

Application of PRA technique for field problem identification

This paper deals with the application of participatory rural appraisal technique for identification of agricultural field problems of Maroorpatti village . The economic importance of problems was also worked out

Genetic Variability for Quantitative Traits in China Aster [Callistephus chinensis (L.) Nees]

A field study was conducted to estimate genetic variability, heritability and genetic advance in 20 genotypes of China aster for 15 traits during the year 2012-13 in Randomized Complete Block Design, with three replications. Results revealed that the magnitude of phenotypic co-efficient of variation (PCV) was higher than genotypic co-efficient of variation (GCV) for all the traits studied. Narrow differences between GCV and PCV were recorded in all the characters except flowering duration, vase-life and shelf-life, indicating little environmental influence on expression of these characters. High (>20%) GCV and PCV were recorded for plant height, number of branches and leaves per plant, flower diameter, number of ray and disc florets/flower head, stalk length, and, number and weight of flowers/plant. Heritability estimates ranged from 28.30% (flowering duration) to 99.54% (flower diameter). High heritability (<60%) was observed for all the traits except flowering duration. High heritability, coupled with high genetic advance as per cent mean, was recorded for flower diameter, stalk-length, number of branches/plant, weight of flowers/plant, days to first flower opening, days to 50 per cent flowering, plant height, number of leaves/plant, number of ray and disc florets/flower head, number of flowers/plant, indicating a possible role of additive gene action. Thus, these traits can be improved through selection and breeding

The use of hydrothermal methods in the synthesis of novel open-framework materials

The preparation of inorganic compounds, exhibiting open-framework structures, by hydrothermal methods has been presented. To illustrate the efficacy of this approach, few select examples encompassing a wide variety and diversity in the structures have been provided. In all the cases, good quality single crystals were obtained, which were used for the elucidation of the structure. In the first example, simple inorganic network compounds based on phosphite and arsenate are described. In the second example, inorganic-organic hybrid compounds involving phosphite/arsenate along with oxalate units are presented. In the third example, new coordination polymers with interesting structures are given. The examples presented are representative of the type and variety of compounds one can prepare by careful choice of the reaction conditions

Voyager 2 and the world of Neptune

After dramatic discoveries during its flybys of Jupiter, Saturn and Uranus, Voyager 2 has now sent back breath- taking images of Neptune and its moons. The major discoveries in the Neptunian system include puzzling weather systems, broad sheet of ring material, peculiar offset and tilting of the magnetic dipole field, six new moons, and atmospheric composition and surface features of the biggest moon, Triton

Surgical vein graft preparation promotes cellular dysfunction, oxidative stress, and intimal hyperplasia in human saphenous vein

IntroductionHuman saphenous vein (HSV) is the most widely used bypass conduit for peripheral and coronary vascular reconstructions. However, outcomes are limited by a high rate of intimal hyperplasia (IH). HSV undergoes a series of ex vivo surgical manipulations prior to implantation, including hydrostatic distension, marking, and warm ischemia in solution. We investigated the impact of surgical preparation on HSV cellular function and development of IH in organ culture. We hypothesized that oxidative stress is a mediator of HSV dysfunction.MethodsHSV was collected from patients undergoing vascular bypass before and after surgical preparation. Smooth muscle and endothelial function were measured using a muscle bath. Endothelial preservation was assessed with immunohistochemical staining. An organ culture model was used to investigate the influence of surgical preparation injury on the development of IH. Superoxide levels were measured using a high-performance liquid chromatography-based assay. The influence of oxidative stress on HSV physiologic responses was investigated by exposing HSV to hydrogen peroxide (H2O2).ResultsSurgical vein graft preparation resulted in smooth muscle and endothelial dysfunction, endothelial denudation, diminished endothelial nitric oxide synthase staining, development of increased IH, and increased levels of reactive oxygen species. Experimental induction of oxidative stress in unmanipulated HSV by treatment with H2O2 promoted endothelial dysfunction. Duration of storage time in solution did not contribute to smooth muscle or endothelial dysfunction.ConclusionsSurgical vein graft preparation causes dysfunction of the smooth muscle and endothelium, endothelial denudation, reduced endothelial nitric oxide synthase expression, and promotes IH in organ culture. Moreover, increased levels of reactive oxygen species are produced and may promote further vein graft dysfunction. These results argue for less injurious means of preparing HSV prior to autologous transplantation into the arterial circulation.Clinical RelevanceApproximately 1,000,000 aortocoronary and peripheral vascular reconstructions are performed annually using human saphenous vein grafts. However, outcomes from this procedure are limited by high rates of graft failure. The leading cause of vein graft failure is intimal hyperplasia. A multifactorial process, intimal hyperplasia is thought to arise at least in part due to vein graft injury. Significant trauma occurs to the graft during surgical harvest and subsequent preparation, significantly impairing cellular function and increasing oxidative stress. Efforts to reduce early vein graft injury during harvest and preparation may have the potential to reduce subsequent vein graft failure in patients