Geometric phases and Wannier functions of Bloch electrons in 1-dimension

We present a formal expression for Wannier functions of composite bands of 1-D Bloch electrons in terms of parallel-transported Bloch functions and their non-Abelian geometric phases. Spatial decay properties of these Wannier functions are studied in the case of simple bands of 1-D model insulator and metal. Within first-principles density functional theory, we illustrate the formalism through the construction of Wannier functions of polyethylene and polyacetylene.Comment: 4 pages, 4 figure

Light interception and yield response of cotton varieties to high density planting and fertilizers in sub-tropical India

Plant density and optimum fertilization are two important agronomic practices to enhance productivity of cotton (Gossypium hirsutum L.) varieties. The objective of this study was to investigate the effect of high density planting (HDPS) and fertilization rate, especially their interactions, on yield, yield components of cotton varieties in sub-tropical India. Split-split plot design was adopted and replicated thrice. The main plots were assigned to low, medium and high plant densities (16.7, 13.3 and 11.1 plants/m2). Pre released cotton varieties TCH-1705 and LH-2298 were tested in low, moderate and high rates of fertilizers recommended for the region (100, 125 and 150 %) in sub-sub plots. Significantly higher seed cotton yield (1148 kg/ha) was achieved in narrow inter row spaced at 60 cm over normal plant row spacing of 90 cm (1025 kg/ha). Compact genotype TCH-1705 was out yielded (1146 kg/ha) over LH 2298(1044 kg/ha). Application of fertilizers at higher rate improved seed cotton yield (1232 kg/ha) Leaf area index (3.8) and light interception (0.98) over blanket recommendation. The results of the study inferred that seed cotton yield improvement was possible under HDPS production system with compact varieties grown at narrow spacing and higher fertilizer dose

Nutrient requirement, canopy development and fruit yield of high density guava (Psidium guajava L.) production in subtropics of Northern Karnataka

Nutrient requirement for guava under high density planting is much higher than normal planting. Combined application of organic manures and chemical fertilizers will enhance nutrient use efficiency. The field experiment was carried out at Raichur, Karnataka, India during 2017 to standardize rate of fertilizers and organic manures for Guava (Psidium guajava L.)  cv. Allahabad safeda under high density planting. Treatments consists of application of fertilizers for normal planting compared with 100:40:75 g NPK/plant as recommended dose of fertilizers (RDF), 75% and 50% of high density planting (HDP) along with 25 kg farmyard manure, organic manure alone and foliar application of urea @ 1 % at 2,3 and 4 months after pruning. Results indicated that application of NPK@ 235: 118: 120 g per plant as per the RDF for HDP along with 25 kg FYM has resulted in taller plants, plant spread E-W as well as N-S directions, canopy volume and leaf area index. Higher fruits/plant, average fruit weight, fruit diameter, fruit length, fruit yield per plant and fruit yield (48.58 t ha-1) was recorded by application of NPK@ 235: 118: 120 g per plant same as that of HDP along with 25 kg FYM. Application of 50 % of HDP recommendation along with foliar application of urea @ 1% at 2, 3 and 4 months after pruning and 25 kg FYM was also found effective in achieving higher fruit yield of guava

Modified planting geometry and fertilizer rate on productivity of corn (Zea mays L.) in Vertisols

A field experiment was conducted at Raichur, Karnataka with an objective to find out production potential of grain corn planted in clumps and rate of fertilizer application. Design followed was split plot and repeated thrice with rate of fertilizer application as main factor and planting geometry as sub factor. Treatments consists of planting corn at 2, 3, 4 seeds/hill compared with single seeds/hill (60 cm x 20 cm) and farmers practice uneven spacing. In clumped plants inter row spacing is similar (60 cm) and intra row distance is differ to maintain uniform plant density (83,333 plants/ha) in each treatment. Recommended dose of fertilizers (RDF) was applied in 2 splits and 150% RDF in 3 splits. Results revealed that planting 2 seeds /hill at 60 cm x 40 cm recorded significantly higher yield, economics of corn as compared to 3 and 4 seeds/hill and farmers practice. As increased plant population per hill maintains higher soil moisture at 75 days after planting (7.5-9.4%) and lower dry matter per plant at harvest (236.3 to 185.5 g) as compared to conventional planting. Application of higher (150%) fertilizers in 3 splits recorded higher dry matter production, grain yield, and economic returns over RDF. This may be useful strategy for corn productivity enhancement by clump planting with higher fertilizer rate

Efficacy of Propanil against Weeds in Direct Seeded Rice and Its Effect on Succeding Crop

Aims: To assess the efficacy of propanil against weeds in direct seeded rice. Place and Duration: A field study was conducted during Kharif 2015 and summer 2016, at Agricultural Research Station, Dhadesugur, University of Agricultural Sciences, Raichur, Karnataka, India. Methodology: An investigation comprises of eight treatments and replicated thrice. The weeds which were dominant in trials field are Echinichloa sp. Panicum repens, Leptochloa chinensis, Brachiaria mutica, Digitaria sanguinalis among grasses, Eclipta alba, Ludwigia parviflora and Commelina communis as broad leaf weeds and Cyperus sp. as sedge. Results: Application of Propanil 80% DF @ 4 kg a.i./ha and twice hand weeded check at 30 and 45 days after sowing found significantly (p=0.05) superior over the application of Propanil 80% DF @ 3 kg a.i./ha and rest of the treatments in controlling the weeds in direct seeded rice and increases the grain yield of rice without any phytotoxic effect. Conclusion: Propanil 80% DF @ 3 kg a.i./ha could be recommended for post-emergence application at 10 to 15 days after sowing of paddy crop to achieve effective control of weeds

Herbicide sequence for weed management in direct seeded rice

An experiment was conducted during Kharif 2014 and 2015 at Agricultural Research Station, Dhadesu-gur, University of Agricultural Sciences, Raichur, Karnataka, India, to know the herbicide sequence for weed man-agement in direct seeded rice. The dominant weeds in direct seeded rice were Echinochloa sp, Panicum repens, Cynodon doctylon, Leptochloa chinensis, Bracharia sp. Ludwigia parviflora, Commelena sp. and Cyperus sp. Pooled data revealed that, application of pyrazosulfuron ethyl 10 % WP at 20 g a.i./ha as pre-emergent herbicide followed by the application of Bispyribac sodium 10 % SC @ 250 ml/ha at 20 to 25 days after sowing as post-emergent herbi-cide in direct seeded rice was most effective in controlling of grasses, broad leaf weeds and sedges and increased the rice grain yield (5583 kg/ha) without any phytotoxic effect and which was onpar with the application of Pendime-thalin 30 EC @ 1 kg a.i. /ha as pre-emergent herbicide followed by one hand weeding at 30 days after sowing and weed free check .Therefore, the application of pre emergent herbicides followed by the post emergent herbicide application can reduce the weed problem in direct seeded rice

LIPOMA OF THE PALATINE TONSILS: A RARE CASE REPORT.

Lipomata are benign tumours and contains abnormal collection of mature adipocytes. They are one of the most common mesenchymal neoplasms in the body. Being extremely rare in the oropharynx,. Only a few cases of tonsillar lipoma have been reported so far. In this article we report a rare case of lipoma in the palatine tonsil with review of the related literature

Guillain-Barré syndrome: a rare association of COVID-19 pneumonia at presentation

COVID-19 is a global pandemic which has varied array of symptoms. A neurotropic presentation has also been described of which the most common is stroke. In this brief communication we report a case of COVID-19 who presented to our hospital with features suggestive of Guillain-Barré syndrome. A 76 year old male presented with chief complains of weakness in both lower limbs. On detailed examination the patient had LMN type quadriparesis without sensory involvement. Diagnosis of GBS was confirmed by CSF and NCV studies and other cases of quadriparesis were ruled out by appropriate investigations and treatment of the same was started. Respiratory examination revealed bilateral basal crepitations and CXR revealed B/L lower zone haziness so a secondary diagnosis of B/L Atypical Pneumonitis suspected COVID-19 was kept. A COVID-19 RTPCR turned out to be negative initially. However, looking at respiratory signs and symptoms along with increase in inflammatory markers a repeat COVID RTPCR was planned which turned out to be positive. Patient was further managed on the line of COVID-19 pneumonitis. He responded well to the treatment and is now asymptomatic on follow up. Nervous system involvement in COVID-19 may have been grossly underestimated. Over the course of this pandemic, an increasing number of COVID-19 patients are being reported with neurological complications. Physicians should be aware of atypical presentation where patient complained of weakness first and had respiratory symptoms later as in our case where early detection of atypical presentations help in better management

Electric and magnetic polarizabilities of hexagonal Ln2CuTiO6 (Ln=Y, Dy, Ho, Er and Yb)

We investigated the rare-earth transition metal oxide series, Ln2CuTiO6 (Ln=Y, Dy, Ho, Er and Yb), crystallizing in the hexagonal structure with non-centrosymmetric P63cm space group for possible occurrences of multiferroic properties. Our results show that while these compounds, except Ln=Y, exhibit a low temperature antiferromagnetic transition due to the ordering of the rare-earth moments, the expected ferroelectric transition is frustrated by the large size difference between Cu and Ti at the B-site. Interestingly, this leads these compounds to attain a rare and unique combination of desirable paraelectric properties with high dielectric constants, low losses and weak temperature and frequency dependencies. First-principles calculations establish these exceptional properties result from a combination of two effects. A significant difference in the MO5 polyhedral sizes for M = Cu and M = Ti suppress the expected co-operative tilt pattern of these polyhedra, required for the ferroelectric transition, leading to relatively large values of the dielectric constant for every compound investigated in this series. Additionally, it is shown that the majority contribution to the dielectric constant arises from intermediate-frequency polar vibrational modes, making it relatively stable against any temperature variation. Changes in the temperature stability of the dielectric constant amongst different members of this series are shown to arise from changes in relative contributions from soft polar modes.Comment: Accepted for publication in Phys. Rev. B (21 pages, 2 Table, 8 Figures

Protein Motifs for Proton Transfers That Build the Transmembrane Proton Gradient

Biological membranes are barriers to polar molecules, so membrane embedded proteins control the transfers between cellular compartments. Protein controlled transport moves substrates and activates cellular signaling cascades. In addition, the electrochemical gradient across mitochondrial, bacterial and chloroplast membranes, is a key source of stored cellular energy. This is generated by electron, proton and ion transfers through proteins. The gradient is used to fuel ATP synthesis and to drive active transport. Here the mechanisms by which protons move into the buried active sites of Photosystem II (PSII), bacterial RCs (bRCs) and through the proton pumps, Bacteriorhodopsin (bR), Complex I and Cytochrome c oxidase (CcO), are reviewed. These proteins all use water filled proton transfer paths. The proton pumps, that move protons uphill from low to high concentration compartments, also utilize Proton Loading Sites (PLS), that transiently load and unload protons and gates, which block backflow of protons. PLS and gates should be synchronized so PLS proton affinity is high when the gate opens to the side with few protons and low when the path is open to the high concentration side. Proton transfer paths in the proteins we describe have different design features. Linear paths are seen with a unique entry and exit and a relatively straight path between them. Alternatively, paths can be complex with a tangle of possible routes. Likewise, PLS can be a single residue that changes protonation state or a cluster of residues with multiple charge and tautomer states