669 research outputs found
ASASSN-14dq: A fast-declining type II-P Supernova in a low-luminosity host galaxy
Optical broadband (UBVRI) photometric and low-resolution spectroscopic
observations of the type II-P supernova (SN) ASASSN-14dq are presented.
ASASSN-14dq exploded in a low-luminosity/metallicity host galaxy UGC 11860, the
signatures of which are present as weak iron lines in the photospheric phase
spectra. The SN has a plateau duration of 90 d, with a plateau decline
rate of 1.38 in V-band which is higher than most type
II-P SNe. ASASSN-14dq is a luminous type II-P SN with a peak -band absolute
magnitude of -17.70.2 mag. The light curve of ASASSN-14dq indicates it
to be a fast-declining type II-P SN, making it a transitional event between the
type II-P and II-L SNe. The empirical relation between the steepness parameter
and mass for type II SNe was rebuilt with the help of
well-sampled light curves from the literature. A mass of
0.029 M was estimated for ASASSN-14dq, which is slightly
lower than the expected mass for a luminous type II-P SN. Using
analytical light curve modelling, a progenitor radius of cm, an ejecta mass of and a total
energy of ergs was estimated for this event. The
photospheric velocity evolution of ASASSN-14dq resembles a type II-P SN, but
the Balmer features (H and H) show relatively slow velocity
evolution. The high-velocity H feature in the plateau phase, the
asymmetric H emission line profile in the nebular phase and the
inferred outburst parameters indicate an interaction of the SN ejecta with the
circumstellar material (CSM).Comment: 28 pages, 29 figures, Accepted in MNRA
Eco-holobiont : a new concept to identify drivers of host-associated microorganisms
Host microbiomes play a critical role in host fitness and health. Whilst the current 'holobiont' concept framework has greatly expanded eco-evolutionary and functional understanding of host-microbiome interactions, the important role of biotic interactions and microbial loop (compositional linkage between soil, plant and animal) in shaping host-microbiome are poorly understood. We proposed an 'eco-holobiont' concept to fill the knowledge gap
Information and Communication Technologies for Integrated Pest Management- Some Experiences
In this transitory and challenging phase of agriculture development and extension, quick and easy transfer of technological information from the research system to end client farmer as well as feedback from farmers to the research system back is very critical and this gap can be easily achieved by the outright and expanding penetration of Information and Communication Technologies (ICTs). Information that is need-based, demand driven, location-specific as well as in local language can be easily provided by internet services and mobile phones. In extension system ICTs can help in emergence of knowledge workers resulting in the realization of a bottom-up, demand-driven paradigm for technology generation, assessment, refinement and transfer ICTs can make significant contribution in increasing the efficiency, productivity and sustainability of small farmers by providing early warning system regarding pest and disease control, new varieties, soil health, water management and weather. Computers, internet, geographical information systems, mobile phones, as well as traditional media such as radio or TV can bring about awareness of up-to-date market information on prices of commodities, inputs and consumer trends which will improve farmers’ livelihoods substantially and have a dramatic impact on their negotiating position and marketing prospects. A number of internet sites have come up to support agricultural development in India. Websites like ikisan.com, krishivihar.com, agriwatch.com and commodityindia.com provides information to farmers on production and marketing of agricultural commodities. In the current changing scenario of emerging pest management problems, ICTs can play an important role in analyzing data regarding pest identification, dissemination and sharing of IPM information, internet based decision support tools, training and spread of scientific documents to other scientists, researchers, extension agencies, farmers as well as for public viewing. Internet and other ICT tools like mobile phones are very fast, persistent, detailed, open and interactive so are much suitable. Internet based services are presently being used for IPM based pest surveillance and advisory projects in management of insects pests of paddy, chickpea as well as pigeon pea. ICTs can provide the farmers with all the necessary information they require their decision regarding pest identification, life cycle, sampling, economic threshold decision, pest distribution, eco-friendly bio-control management tactics, pesticides availability as well as their environmental impact and safety risks. With growing popularity of smart mobile phones, hand held computers and global positioning systems IPM extension professionals and farmers are able to access relevant information anywhere anytime as well as inspiring insect pest informatics experts to create and standardize IPM information relevant to pest of specific area and time
Role of Krishi Vigyan Kendras (KVKs) in Agricultural Extension: An Overview
Krishi Vigyan Kendra (KVK) is the only institution at the district level in India for technological backstopping in agriculture and allied sectors. All KVKs are envisaged to reduce the time lag between generation of technology at the research institution and its application to the location specific farmer fields for increasing production, productivity and net farm income on a sustained basis. Each KVK has been provided with a team of multi-disciplinary subject matter specialists for taking up the activities of a KVK. Each KVK has a provision of Scientific Advisory Committee (SAC), the function of this Committee is to provide advice to the KVK in formulation of annual technical programme and also to review the performance mandated activities. KVKs are implementing various technological interventions based on the needs of the farming community. The paper tries to critically examine the developments so far and what needs to be done further to strengthen the KVKs
Humidity and low pH boost occurrence of Onygenales fungi in soil at global scale
Soils are important reservoirs for potential human pathogens and opportunistic fungi such as the dermatophyte or dimorphic fungi in the order Onygenales. In soils, these taxa are decomposers but many of them have the potential to cause respiratory and skin diseases in humans and, in some cases, systemic infections. Even so, the factors that determine the biogeography and ecology of order Onygenales remain largely undocumented. To address this knowledge gap, we surveyed members of Onygenales from topsoil fungal communities at 235 sites across six continents and provided a first global atlas. We retrieved 4.3% of the total fungal sequences (∼420 Onygenales) across nine biomes ranging from deserts to tropical forests. This work advances our knowledge on the ecology and global distribution of order Onygenales and suggests the hypothesis that wet and acid soils support the larger proportions of these fungi, while their richness is constrained by aridity.C.C. and L.S. wish to thank the Italian National Program for Antarctic Research (PNRA) for supporting their research. M.D-B. is supported by a project from the Spanish Ministry of Science and Innovation (PID2020-115813RA-I00), and a project PAIDI 2020 from the Junta de Andalucía (P20_00879). Microbial distribution and colonization research in B.K.S. lab is funded by Australian Research Council (DP190103714). E.G. is supported by the European Research Council grant agreement 647038 (BIODESERT)
All together now : limitations and recommendations for the simultaneous analysis of all eukaryotic soil sequences
The soil environment contains a large, but historically underexplored, reservoir of biodiversity. Sequencing prokaryotic marker genes has become commonplace for
the discovery and characterization of soil bacteria and archaea. Increasingly, this approach is also applied to eukaryotic marker genes to characterize the diversity and distribution of soil eukaryotes. However, understanding the properties and limitations of eukaryotic marker sequences is essential for correctly analysing, interpreting, and synthesizing the resulting data. Here, we illustrate several biases from sequencing data that affect measurements of biodiversity that arise from variation in morphology, taxonomy and phylogeny between organisms, as well as from sampling designs. We recommend analytical approaches to overcome these limitations, and outline how the benchmarking and standardization of sequencing protocols may improve the comparability of the data
Role of Krishi Vigyan Kendras (KVKs) in Agricultural Extension: An Overview
Krishi Vigyan Kendra (KVK) is the only institution at the district level in India for technological backstopping in agriculture and allied sectors. All KVKs are envisaged to reduce the time lag between generation of technology at the research institution and its application to the location specific farmer fields for increasing production, productivity and net farm income on a sustained basis. Each KVK has been provided with a team of multi-disciplinary subject matter specialists for taking up the activities of a KVK. Each KVK has a provision of Scientific Advisory Committee (SAC), the function of this Committee is to provide advice to the KVK in formulation of annual technical programme and also to review the performance mandated activities. KVKs are implementing various technological interventions based on the needs of the farming community. The paper tries to critically examine the developments so far and what needs to be done further to strengthen the KVKs
- …