1,181 research outputs found
Research Notes: Variation for seed yield, its quality and nutritional traits in soybeans
To bring about genetic improvement for any economic trait in economic plants, the foremost prerequisite is the presence of sufficient amount of genetic variability for the trait under improvement in the organism t o be improved. In the present investigation, an attempt has been made to get the information on nature and magnitude of variability for various seed quality traits along with seed yield traits in the soybean germplasm maintained at the Himachal Pradesh Agricultural University, Palampur. Materials and methods: The material for the present study consisted of 250 diverse genotypes of soybeans of both indigenous and exotic origin , and 5 standard checks
Molecular Diversity in Sewan Grass (\u3cem\u3eLasiurus sindicus\u3c/em\u3e Henr.): A Natural Inhabitant of Hot Arid Ecosystem of Thar Desert
Lasiurus sindicus Henr., locally known as “Sewan”, a member of family poaceae, is a tufted perennial, forming a more or less oblique and woody rhizomatous rootstock with many shoots arising from the base, often appearing almost bushy. This grass has developed a number of morphological, anatomical and biochemical strategies to withstand the extreme climatic conditions. The leaves show characteristic C4 NADP-ME type of anatomy and have developed sclerenchyma to impart mechanical strength during drought and high wind. Sewan is a dominating grass species of Dichanthium-Cenchrus–Lasiurus type grass lands of hot arid ecosystem of Great Indian Desert, covering western Rajasthan and parts of Pakistan. It grows naturally in wide range of dry areas covering North Africa, Sudano-Sahelian Africa, East Africa and Asia. It thrives well in dry climate receiving annual rainfall below 250 mm prevailing between 25-27°N latitude on well aerated alluvial soils or light sandy soils with a pH of 8.5, rocky ground and gravelly soils. Though this grass tolerates prolonged droughts but has not been found growing in higher rainfall zones and faces a serious threat of becoming an endangered due to changes in the land use pattern, increase in soil moisture regime and overgrazing.
The Sewan grass, considered as the “King of Desert Grasses”, is quite palatable and nutritious for the livestock. Crude protein in young leaves varies from 7 to 14% and remains high even at maturity leading to its better suitability for efficient utilization in the animal based agri-horti-pastoral production system prevalent in hyper arid regions of western Rajasthan. In the three districts of western Rajasthan viz. Bikaner, Barmer and Jaisalmer the sustainability and productivity of livestock mainly depends on the sewan based pasture system. The present study was undertaken to analyze the extent of genetic variability existing among the L. sindicus germplasm, collected from Bikaner, Barmer and Jaisalmer, the diversity rich districts of hyper-arid Rajasthan, using ISSR and RAPD markers, for its importance in determining survival under changing climate
Molecular Dipolar Crystals as High Fidelity Quantum Memory for Hybrid Quantum Computing
We study collective excitations of rotational and spin states of an ensemble
of polar molecules, which are prepared in a dipolar crystalline phase, as a
candidate for a high fidelity quantum memory. While dipolar crystals are formed
in the high density limit of cold clouds of polar molecules under 1D and 2D
trapping conditions, the crystalline structure protects the molecular qubits
from detrimental effects of short range collisions. We calculate the lifetime
of the quantum memory by identifying the dominant decoherence mechanisms, and
estimate their effects on gate operations, when a molecular ensemble qubit is
transferred to a superconducting strip line cavity (circuit QED). In the case
rotational excitations coupled by dipole-dipole interactions we identify
phonons as the main limitation of the life time of qubits. We study specific
setups and conditions, where the coupling to the phonon modes is minimized.
Detailed results are presented for a 1D dipolar chain
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Direct detection of alpha synuclein oligomers in vivo
Background: Rat models of Parkinson’s disease are widely used to elucidate the mechanisms underlying disease etiology or to investigate therapeutic approaches. Models were developed using toxins such as MPTP or 6-OHDA to specifically target dopaminergic neurons resulting in acute neuronal loss in the substantia nigra or by using viral vectors to induce the specific and gradual expression of alpha synuclein in the substantia nigra. The detection of alpha- synuclein oligomers, the presumed toxic species, in these models and others has been possible using only indirect biochemical approaches to date. Here we coinjected AAVs encoding alpha-synuclein fused to the N- or C-terminal half of VenusYFP in rat substantia nigra pars compacta and describe for the first time a novel viral vector rodent model with the unique ability to directly detect and track alpha synuclein oligomers ex vivo and in vivo. Results: Viral coinjection resulted in widespread VenusYFP signal within the nigrostriatal pathway, including cell bodies in the substantia nigra and synaptic accumulation in striatal terminals, suggestive of in vivo alpha-synuclein oligomers formation. Transduced rats showed alpha-synuclein induced dopaminergic neuron loss in the substantia nigra, the appearance of dystrophic neurites, and gliosis in the striatum. Moreover, we have applied in vivo imaging techniques in the living mouse to directly image alpha-synuclein oligomers in the cortex. Conclusion: We have developed a unique animal model that provides a tool for the Parkinson’s disease research community with which to directly detect alpha- synuclein oligomers in vivo and screen therapeutic approaches targeting alpha-synuclein oligomers
Effect of high day and night temperature regimes on tomato (Solanum lycopersicum) genotypes
Five tomato (Solanum lycopersicum L.) genotypes, including heat tolerant (Pusa Sadabahar, Booster, Pusa Sheetal), one F1 combination (Pusa Sheetal × Pusa Sadabahar ) and one susceptible genotype (Pusa Rohini) were grown under phytotron under four temperature regimes, i.e. 20/24, 22/26, 24/32, 27/37°C night (11 hours)/day (13 hours) temperature, respectively. Pusa Sadabahar and Booster recorded high value of relative water content (RWC) and low value of membrane injury index (MII) both at normal and high temperature conditions. High value of chlorophyll a and chlorophyll b ratio was recorded in Pusa Sadabahar and Pusa Sheetal×Pusa Sadabahar under all the temperature regimes showed their tolerance to high temperature. Normal (more than 80 percent) flowering and fruiting was recorded in all the genotypes at 20/24°C & 22/26°C. However at 24/32°C Pusa Sadabahar recorded 65 per cent fruit set and other genotypes 25 to 49 percent fruit setting only. None of the genotypes could record fruit set at 27/37°C, except Pusa Sadabahar which could set few small fruits (19%). Pollen germination was maximum (ranging from 21.8 - 62.9%) in Pusa Sadabahar under all temperature regimes. The susceptible genotype, Pusa Rohini recorded exerted stigma in 100% flowers at 27/37°C temperature whereas it was 75% in tolerant genotype Pusa Sadabahar. Night/day temperature 22/26°C was optimum for fruit set, pollen viability and normal stigma development in tomato. High night temperature (³ 26°C ± 2°C) at flowering was the major factor in reducing fruit set in tomato than the day temperature. The study showed that day temperature of ³ 35°C and night temperature of ³ 26oC may be used for screening tomato against high temperature tolerance
Sequence Characterisation and Genotyping of Allelic Variants of Beta Casein Gene Establishes Native Cattle of Ladakh to be a Natural Resource for A2 Milk
Bovine milk is regarded as nature's perfect food due to presence of vital nutrients. However some peptides are generated after proteolytic digestion of β-casein that have opioid properties and may increase the risk of chronic diseases. There are 13 genetic variants of bovine beta-casein; out of these A1 and A2 are the most common in dairy cattle breeds. The A1 and A2 variants differ only at position 67, which is histidine in A1 or proline in A2 milk. Earlier published reports have indicated that A1 β casein could be responsible for several health disorders like diabetes, coronary heart disease etc. while A2 β-casein is generally considered safe for human consumption. In the present study, an effort was made to sequence characterize β casein gene and identify allelic distribution of A1A2 alleles in native cattle of Ladakh region adapted to high altitude and low oxygen condition. The data showed 2 non-synonymous variations in coding region, while 5’UTR was completely conserved. The 3’UTR showed 2 more variations in Ladakhi samples. Further, the genotyping in 85 Ladakhi cattle for A1A2 alleles revealed that in Ladakhi cattle, A2 allele is predominantly present as reported for some of the other Indian breeds. The frequency of A2 allele was 0.90 and frequency of A2A2 genotype was found to be 0.79 in Ladakhi cattle. The present data strongly indicate that local cattle of Ladakh with higher frequency of A2 allele and A2A2 genotype is natural resource for A2 milk. Systematic efforts should be made for long term conservation and genetic improvement of this invaluable genetic resource of Ladakh
Quantum Simulations of Extended Hubbard Models with Dipolar Crystals
In this paper we study the realization of lattice models in mixtures of
atomic and dipolar molecular quantum gases. We consider a situation where polar
molecules form a self-assembled dipolar lattice, in which atoms or molecules of
a second species can move and scatter. We describe the system dynamics in a
master equation approach in the Brownian motion limit of slow particles and
fast phonons, which we find appropriate for our system. In a wide regime of
parameters, the reduced dynamics of the particles leads to physical
realizations of extended Hubbard models with tuneable long-range interactions
mediated by crystal phonons. This extends the notion of quantum simulation of
strongly correlated systems with cold atoms and molecules to include
phonon-dynamics, where all coupling parameters can be controlled by external
fields.Comment: 44 pages, 14 figure
Continuum field description of crack propagation
We develop continuum field model for crack propagation in brittle amorphous
solids. The model is represented by equations for elastic displacements
combined with the order parameter equation which accounts for the dynamics of
defects. This model captures all important phenomenology of crack propagation:
crack initiation, propagation, dynamic fracture instability, sound emission,
crack branching and fragmentation.Comment: 4 pages, 5 figures, submitted to Phys. Rev. Lett. Additional
information can be obtained from http://gershwin.msd.anl.gov/theor
Simultaneous Observation of Carrier-Specific Redistribution and Coherent Lattice Dynamics in 2H-MoTe with Femtosecond Core-Level Spectroscopy
We employ few-femtosecond extreme ultraviolet (XUV) transient absorption
spectroscopy to reveal simultaneously the intra- and interband carrier
relaxation and the light-induced structural dynamics in nanoscale thin films of
layered 2H-MoTe semiconductor. By interrogating the valence electronic
structure via localized Te 4 (39-46 eV) and Mo 4 (35-38
eV) core levels, the relaxation of the photoexcited hole distribution is
directly observed in real time. We obtain hole thermalization and cooling times
of 155 fs and 38090 fs, respectively, and an electron-hole
recombination time of 1.50.1 ps. Furthermore, excitations of coherent
out-of-plane A (5.1 THz) and in-plane E (3.7 THz) lattice
vibrations are visualized through oscillations in the XUV absorption spectra.
By comparison to Bethe-Salpeter equation simulations, the spectral changes are
mapped to real-space excited-state displacements of the lattice along the
dominant A coordinate. By directly and simultaneously probing the
excited carrier distribution dynamics and accompanying femtosecond lattice
displacement in 2H-MoTe within a single experiment, our work provides a
benchmark for understanding the interplay between electronic and structural
dynamics in photoexcited nanomaterials
Thermodynamics of Dipolar Chain Systems
The thermodynamics of a quantum system of layers containing perpendicularly
oriented dipolar molecules is studied within an oscillator approximation for
both bosonic and fermionic species. The system is assumed to be built from
chains with one molecule in each layer. We consider the effects of the
intralayer repulsion and quantum statistical requirements in systems with more
than one chain. Specifically, we consider the case of two chains and solve the
problem analytically within the harmonic Hamiltonian approach which is accurate
for large dipole moments. The case of three chains is calculated numerically.
Our findings indicate that thermodynamic observables, such as the heat
capacity, can be used to probe the signatures of the intralayer interaction
between chains. This should be relevant for near future experiments on polar
molecules with strong dipole moments.Comment: 15 pages, 5 figures, final versio
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