409 research outputs found
Infinity Learning: Learning Markov Chains from Aggregate Steady-State Observations
We consider the task of learning a parametric Continuous Time Markov Chain
(CTMC) sequence model without examples of sequences, where the training data
consists entirely of aggregate steady-state statistics. Making the problem
harder, we assume that the states we wish to predict are unobserved in the
training data. Specifically, given a parametric model over the transition rates
of a CTMC and some known transition rates, we wish to extrapolate its steady
state distribution to states that are unobserved. A technical roadblock to
learn a CTMC from its steady state has been that the chain rule to compute
gradients will not work over the arbitrarily long sequences necessary to reach
steady state ---from where the aggregate statistics are sampled. To overcome
this optimization challenge, we propose -SGD, a principled stochastic
gradient descent method that uses randomly-stopped estimators to avoid infinite
sums required by the steady state computation, while learning even when only a
subset of the CTMC states can be observed. We apply -SGD to a
real-world testbed and synthetic experiments showcasing its accuracy, ability
to extrapolate the steady state distribution to unobserved states under
unobserved conditions (heavy loads, when training under light loads), and
succeeding in difficult scenarios where even a tailor-made extension of
existing methods fails
Prospects for durable resistance against an old soybean enemy: a four-decade journey from Rpp1 (Resistance to Phakopsora pachyrhizi) to Rpp7
Open Access Journal; Published online: 1 July 2019Soybean rust (SBR), caused by Phakopsora spp., is a major global concern for soybean producers. SBR causing fungi are polycyclic and obligate biotrophs, rendering the study of their biology particularly tedious. Over the past four decades, substantial progress has been made towards understanding the epidemiology of the disease, the identification of sources of resistance, and the mapping of soybean loci conferring resistance to P. pachyrhizi (Rpp genes), since this species is particularly well established and widespread in many soybean growing areas. Although host-plant resistance is generally considered as the most desirable solution from an environmental, economic, and social perspective, other disease control approaches such as agronomic practices and chemical application are also important, and influence rust epidemiology as well as the durability of host plant resistance. This review focusses primarily on genetic aspects of SBR management and summarizes the research in the following areas: SBR symptoms, aetiology, pathogenic variation and population structure of Phakopsora populations, expression of soybean resistance to Phakopsora infection, genetics and molecular diagnostics of host resistance to pathogen, and resistance gene deployment approaches. Finally, the role of multidisciplinary strategies is discussed for achieving higher durability of SBR resistance in soybean
Proteome profile and functional classification of proteins in Arabidopsis thaliana (Landsberg erecta) mature pollen
Proteome analysis of mature Arabidopsis thaliana (Landsberg erecta ecotype) pollen was conducted using two-dimensional gel electrophoresis and mass spectrometry. A total of 960 spots were resolved on pH 4–7 IPG strips and 110 distinct proteins were identified from 150 spots analyzed. The identified proteins were categorized based on their functional role in the pollen, which included proteins involved in energy regulation, defense-related mechanisms, calcium-binding and signaling, cytoskeletal formation, pollen allergens, glycine-rich proteins (GRPs), and late embryogenesis abundant (LEA) proteins. These proteins potentially play important roles in pollen function at maturity and during subsequent germination and tube growth. Some of the proteins identified were related to known pollen-specific transcripts, while some were similar to proteins found in the seed. In this study, 66 new proteins were identified which were not reported in two other recent studies on Arabidopsis pollen, 17 proteins were common in all three studies, and 35 or 26 proteins reported here had an overlap with one or the other two studies. These differences may be attributed to the methods of protein extraction, spot selection for analysis, and the ecotype used. Together, the three studies provide a broad spectrum of the Arabidopsis pollen proteome
Sensitivity Analysis for Decisive Design Parameters for Energy and Indoor Visual Performances of a Glazed Façade Office Building
The large size of a glazed component allows greater access to natural light inside and a wider view of the outdoors while protecting the inside from extreme weather conditions. However, glazed components make buildings energy inefficient compared to opaque components if not designed suitably, and sometimes they create glare discomforts too. In order to protect against excessive natural light and direct sunlight and for privacy, dynamic shading devices are integrated into the glazed façade. In this study, the impact of various glazing and shading design parameters has been investigated by performing uncertainty and sensitivity analyses. The uncertainty analysis indicates that the variance coefficients for the source energy use, lighting energy use, useful daylight illuminance (UDI), and shade-deployed time fraction are in the ranges of 15.04–30.47, 39.05–45.06, 40.57–49.92, and 19.35–52%, respectively. The dispersion in the energy and indoor visual performance is evident by the large variation in the source energy consumption and UDI (500–2000), which vary in the ranges of 250–450 kWh/(m2-year) and 5–90%. Furthermore, a sensitivity analysis identified the window-to-wall ratio (WWR), aspect ratio (ASR), glazing type (Gt), absorptance of the wall
(Aw), and shade transmittance (ST) as major influences of the
parameters. Each of the identified parameters has a different proportionate impact depending on the façade orientation and performance parameters
Record High Efficiency Screen-Printed Belt Co-Fired Cells on Cast Multi-Crystalline Silicon
Presented at the 19th European Photovoltaic Solar Energy Conference and Exhibition, Paris, France; June 7-11, 2004.Record-high efficiency screen-printed 4 cm(2) solar cells were achieved on HEM and Baysix cast multi-crystalline silicon. These cells were fabricated using a simple, manufacturable process involving POCl3
diffusion for a 45 Ω/ ٱ emitter, PECVD SiN(x):H deposition for a single-layer antireflection coating and rapid co-firing
of an Ag grid, an Al back contact, and Al-BSF formation in a belt furnace. This process scheme resulted in effective impurity gettering and defect passivation. It also contributed to good ohmic contacts with series resistance of < 1Ω-cm(2), back surface recombination velocity of < 500 cm(2)/s, high average bulk lifetimes in the range of 100-250 μs after cell processing and fill factors of ~0.78. These parameters resulted in record high, 16.9% and 16.8%
efficient screen-printed cells on HEM (Heat Exchanger Method) and Baysix mc-Si (confirmed by NREL). The identical process applied to the un-textured Float zone (FZ) wafers gave an efficiency of 17.2%. The optimized co-firing cycle, when applied to HEM mc-Si wafers with starting lifetimes varying over a wide range from 4 - 70 μs,
resulted in a very tight efficiency range of 16.6% to 16.8% as a result of efficient defect gettering and passivation.
Model calculations performed using the simple cell design and measured cell parameters agreed well with the experimental cell efficiency
A probable pathway of ureide assimilation in pigeon pea pods
Ureides (allantoin and allantoic acid) and the activities of glutamine synthetase, glutamate dehydrogenase, uricase. allantoinase and urease, the enzymes presumbly involved in the assimilation of ureides, were determined both in the vegetative organs and reproductive structures at 15-day interval starting from day 75 after sowing to complete maturity of the crop (day 120 after sowing). Based on the concentration of ureides and the distribution of the above enzymes in various plant parts, a probable pathway of ureide assimilation in pigeonpea pods has been proposed
An ethnomedicinal survey of traditionally used medicinal plants from Charkhi Dadri district, Haryana: an attempt towards documentation and preservation of ethnic knowledge
436-450Medicinal plants have remained an integral source of therapeutics for primary healthcare since antiquity. The information pertaining to usage of plants is either inherited from elders or acquired through trials or the experience of others but is not documented frequently. South Haryana is one such rich storehouse of ethnomedicinal knowledge. Hence, ethnomedicinally important plants from Charkhi Dadri district of Haryana state were documented in the present study. The data was collected through field surveys and in-depth interviews organized in the fields during the years 2018-19. Factor of informant consensus was also calculated. A total of 90 ethnomedicinal plants were identified, belonging to 41 families and 79 genera. Majority of plants were herbs (47.7%), followed by trees (30%). Leguminosae (10%) represented the maximum number of plants, followed by Solanaceae (6.6% each) and Amaranthaceae, Lamiaceae and Poaceae (5.5% each). A total of 64 ailments were reported to be treated traditionally by ethnomedicinal plants in the area. The most commonly treated diseases were menorrhagia, skin boils, typhoid, diabetes, piles and diarrhoea. It was observed that the majority of plants were used freshly to extract juice, followed by powder and decoction and rarely as tea or oil forms. The present study provides comprehensive ethnomedicinal data including vernacular and botanical names, names of the family, mode of preparation, administration and dosage of plant drugs and diseases treated. It was concluded that this region still possesses numerous useful ethnomedicinal knowledge and may contribute to further herbal drug development programs
Adenovirus vector expressing Stx1/Stx2-neutralizing agent protects piglets infected with Escherichia coli O157: H7 against fatal systemic intoxication
Hemolytic-uremic syndrome (HUS), caused by Shiga toxin (Stx)-producing Escherichia coli (STEC), remains untreatable. Production of human monoclonal antibodies against Stx, which are highly effective in preventing Stx sequelae in animal models, is languishing due to cost and logistics. We reported previously that the production and evaluation of a camelid heavy-chain-only V(H) domain (VHH)-based neutralizing agent (VNA) targeting Stx1 and Stx2 (VNA-Stx) protected mice from Stx1 and Stx2 intoxication. Here we report that a single intramuscular (i.m.) injection of a nonreplicating adenovirus (Ad) vector carrying a secretory transgene of VNA-Stx (Ad/VNA-Stx) protected mice challenged with Stx2 and protected gnotobiotic piglets infected with STEC from fatal systemic intoxication. One i.m. dose of Ad/VNA-Stx prevented fatal central nervous system (CNS) symptoms in 9 of 10 animals when it was given to piglets 24 h after bacterial challenge and in 5 of 9 animals when it was given 48 h after bacterial challenge, just prior to the onset of CNS symptoms. All 6 placebo animals died or were euthanized with severe CNS symptoms. Ad/VNA-Stx treatment had no impact on diarrhea. In conclusion, Ad/VNA-Stx treatment is effective in protecting piglets from fatal Stx2-mediated CNS complications following STEC challenge. With a low production cost and further development, this could presumably be an effective treatment for patients with HUS and/or individuals at high risk of developing HUS due to exposure to STEC
An ethnomedicinal survey of traditionally used medicinal plants from Charkhi Dadri district, Haryana: an attempt towards documentation and preservation of ethnic knowledge
Medicinal plants have remained an integral source of therapeutics for primary healthcare since antiquity. The information pertaining to usage of plants is either inherited from elders or acquired through trials or the experience of others but is not documented frequently. South Haryana is one such rich storehouse of ethnomedicinal knowledge. Hence, ethnomedicinally important plants from Charkhi Dadri district of Haryana state were documented in the present study. The data was collected through field surveys and in-depth interviews organized in the fields during the years 2018-19. Factor of informant consensus was also calculated. A total of 90 ethnomedicinal plants were identified, belonging to 41 families and 79 genera. Majority of plants were herbs (47.7%), followed by trees (30%). Leguminosae (10%) represented the maximum number of plants, followed by Solanaceae (6.6% each) and Amaranthaceae, Lamiaceae and Poaceae (5.5% each). A total of 64 ailments were reported to be treated traditionally by ethnomedicinal plants in the area. The most commonly treated diseases were menorrhagia, skin boils, typhoid, diabetes, piles and diarrhoea. It was observed that the majority of plants were used freshly to extract juice, followed by powder and decoction and rarely as tea or oil forms. The present study provides comprehensive ethnomedicinal data including vernacular and botanical names, names of the family, mode of preparation, administration and dosage of plant drugs and diseases treated. It was concluded that this region still possesses numerous useful ethnomedicinal knowledge and may contribute to further herbal drug development programs
Introgression of “ QTL‐hotspot ” region enhances drought tolerance and grain yield in three elite chickpea cultivars
With an aim of enhancing drought tolerance using a marker‐assisted backcrossing (MABC) approach, we introgressed the “QTL‐hotspot” region from ICC 4958 accession that harbors quantitative trait loci (QTLs) for several drought‐tolerance related traits into three elite Indian chickpea (Cicer arietinum L.) cultivars: Pusa 372, Pusa 362, and DCP 92‐3. Of eight simple sequence repeat (SSR) markers in the QTL‐hotspot region, two to three polymorphic markers were used for foreground selection with respective cross‐combinations. A total of 47, 53, and 46 SSRs were used for background selection in case of introgression lines (ILs) developed in genetic backgrounds of Pusa 372, Pusa 362, and DCP 92‐3, respectively. In total, 61 ILs (20 BC3F3 in Pusa 372; 20 BC2F3 in Pusa 362, and 21 BC3F3 in DCP 92‐3), with >90% recurrent parent genome recovery were developed. Six improved lines in different genetic backgrounds (e.g. BGM 10216 in Pusa 372; BG 3097 and BG 4005 in Pusa 362; IPC(L4‐14), IPC(L4‐16), and IPC(L19‐1) in DCP 92‐3) showed better performance than their respective recurrent parents. BGM 10216, with 16% yield gain over Pusa 372, has been released as Pusa Chickpea 10216 by the Central Sub‐Committees on Crop Standards, Notification and Release of Varieties of Agricultural Crops, Ministry of Agriculture and Farmers Welfare, Government of India, for commercial cultivation in India. In summary, this study reports introgression of the QTL‐hotspot for enhancing yield under rainfed conditions, development of several introgression lines, and release of Pusa Chickpea 10216 developed through molecular breeding in India
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