1,035 research outputs found
Structural origins of electronic conduction in amorphous copper-doped alumina
We perform an {\it ab initio} modeling of amorphous copper-doped alumina
(a-AlO:Cu), a prospective memory material based on resistance
switching, and study the structural origin of electronic conduction in this
material. We generate molecular dynamics based models of a-AlO:Cu at
various Cu-concentrations and study the structural, electronic and vibrational
properties as a function of Cu-concentration. Cu atoms show a strong tendency
to cluster in the alumina host, and metallize the system by filling the band
gap uniformly for higher Cu-concentrations. We also study thermal fluctuations
of the HOMO-LUMO energy splitting and observe the time evolution of the size of
the band gap, which can be expected to have an important impact on the
conductivity. We perform a numerical computation of conduction pathways, and
show its explicit dependence on Cu connectivity in the host. We present an
analysis of ion dynamics and structural aspects of localization of classical
normal modes in our models
Economic Analysis of Fish Production Using Different Feed Types Practiced in Dhanusha District, Nepal
A study on the economic analysis of fish production using different feed types practiced in Dhanusha district was conducted in 2018. Out of 600 fish farmers, sixty fish farmers(10%) from the Fish Superzone region i.e. Janakpur sub-metropolitan city, Bideh municipality, Sahidnagar municipality, Kamala municipality, Hanspur municipality, Janaknandani rural municipality and Aaurahi rural municipality, selected using simple random sampling, were surveyed using semi-structured questionnaire. The study revealed that locally formulated mash feed was commonly used feed type in which rice bran and mustard oil cake (RB+MOC) was the principle feed ingredient. 55% of the farmers used rice bran and mustard oil cake (RB+MOC), 20% used rice bran, mustard oil cake and soybean (RB+MOC+SOB), 10% used rice bran, mustard oil cake and fish meal (RB+MOC+FM) and 15% farmers mineral and vitamin (RB+MOC+MIN/VIT) in their feed formulation. The productivity of the fish production in feed type RB+MOC+SOB (3.41±1.02) was significantly higher than other feed type. The total variable cost per ha (5.23±2.11) was found significantly(p<0.05) higher in feed type RB+MOC+SOB. Similarly, gross margin (4.44±2.74) received by farmers of feed type RB+MOC+SOB was also significantly high(p<0.05). The Benefit: Cost (B:C) ratio of the study area was found to be 1.69, high being of feed type RB+MOC+SOB(1.84) compared to others. The feed type RB+MOC+SOB is seen as a economically profitable one in the study area because of the high productivity, profit and B:C ratio. High feed cost was the major problem followed by the unavailability of feed. Fish farming can be a profitable business in Dhanusha with large opportunity to increase the fish production with increasing protein sources in the feed used. Farmers should be provided sufficient information, trainings and be encouraged to incorporate the protein rich sources like soybean and fish meal in the feed prepared to increase the productivity and ultimately return
Neuroendocrine tumours of the head and neck: anatomical, functional and molecular imaging and contemporary management
Neuroendocrine tumours (NETs) of the head and neck are rare neoplasms and can be of epithelial or non-epithelial differentiation. Although the natural history of NETs is variable, it is crucial to establish an early diagnosis of these tumours as they can be potentially curable. Conventional anatomical imaging and functional imaging using radionuclide scintigraphy and positron emission tomography/computed tomography can be complementary for the diagnosis, staging and monitoring of treatment response. This article describes and illustrates the imaging features of head and neck NETs, discusses the potential future role of novel positron-emitting tracers that are emerging into clinical practice and reviews contemporary management of these tumours. Familiarity with the choice of imaging techniques and the variety of imaging patterns and treatment options should help guide radiologists in the management of this rare but important subgroup of head and neck neoplasms
Community Biodiversity Management: Promoting resilience and the conservation of plant genetic resources
This book is the first to set out a clear overview of CBM as a methodology for meeting socio-environmental changes. CBM is shown to be a key strategy that promotes community resilience, and contributes to the conservation of plant genetic resources. The authors present the underlying concepts and theories of CBM as well as its methodology and practices, and introduce case studies primarily from Brazil, Ethiopia, France, India, and Nepal. Contributors include farmers, leaders of farmers’ organizations, professionals from conservation and development organizations, students and scientists
Low-temperature magneto-thermal transport investigation of a Ni-based superconductor BaNi2As2: Evidence for fully gapped superconductivity
We have performed low-temperature specific heat and thermal conductivity
measurements of the Ni-based superconductor BaNiAs ( =
0.7 K) in magnetic field. In zero field, thermal conductivity shows -linear
behavior in the normal state and exhibits a BCS-like exponential decrease below
. The field dependence of the residual thermal conductivity
extrapolated to zero temperature is indicative of a fully gapped
superconductor. This conclusion is supported by the analysis of the specific
heat data, which are well fit by the BCS temperature dependence from
down to the lowest temperature of 0.1 K.Comment: Physical Review Letters, to be publishe
Evaluation of Onion Genotypes for Growth and Bulb Yield in Mid Hill of Nepal
Experiments were conducted at Horticulture Research Division (HRD), Khumaltar, Lalitpur; and Horticulture Research Station (HRS), Kimugaun, Dailekh in 2017/18 to evaluate the high yielding open pollinated genotypes of onion in mid hills of both locations. Five onion genotypes namely AVON-1016, AVON-1027, AVON-1028, AVON-1052, AVON-1074 and AVON-1103 received from Asian Vegetable Research and Development Centre were evaluated with local check variety and recommended variety Red Creole in both locations in randomized complete block design with 4 replications. The main objective of the experiment is to findout the high yielding open pollinated onion genotypes for mid hill condition.The pooled analysis of data over locations showed significant differences on plant height, neck diameter, bulb diameter, weight of bulbs and adjusted bulb yield per hectare. Introduced genotypes AVON 1027 (38.83 t/ha), AVON 1052 (31.97 t/ha) and AVON 1028 (31.48 t/ha) produced significantly higher yield than recommended and commercially cultivated check variety Red Creole (27.04 t/ha). Therefore the genotype AVON 1027 can be selected as the best genotype for growing in mid hills of Nepa
Fully gapped superconductivity in Ni-pnictide superconductors BaNi2As2 and SrNi2P2
We have performed low-temperature specific heat and thermal conductivity
measurements on the Ni-pnictide superconductors BaNiAs
(=0.7 K and SrNiP (=1.4 K). The temperature
dependences and of the two compounds are similar to the
results of a number of s-wave superconductors. Furthermore, the concave field
responses of the residual for BaNiAs rules out the presence of
nodes on the Fermi surfaces. We postulate that fully gapped superconductivity
could be universal for Ni-pnictide superconductors. Specific heat data on
BaLaNiAs shows a mild suppression of and
relative to BaNiAs.Comment: 5 pages, 3 figures, to be published in J. Phys.: Conf. Se
Nonlinear lattice dynamics as a basis for enhanced superconductivity in YBa2Cu3O6.5
THz-frequency optical pulses can resonantly drive selected vibrational modes
in solids and deform their crystal structure. In complex oxides, this method
has been used to melt electronic orders, drive insulator to metal transitions
or induce superconductivity. Strikingly, coherent interlayer transport strongly
reminiscent of superconductivity can be transiently induced up to room
temperature in YBa2Cu3O6+x. By combining femtosecond X-ray diffraction and ab
initio density functional theory calculations, we determine here the crystal
structure of this exotic non-equilibrium state. We find that nonlinear lattice
excitation in normal-state YBa2Cu3O6+x at 100 K causes a staggered
dilation/contraction of the Cu-O2 intra/inter- bilayer distances, accompanied
by anisotropic changes in the in-plane O-Cu-O bond buckling. Density functional
theory calculations indicate that these motions cause dramatic changes in the
electronic structure. Amongst these, the enhancement in the dx2-y2 character of
the in-plane electronic structure is likely to favor superconductivity.Comment: 28 pages, including Supplemen
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