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The efficacy and sustainability of the CIMBAA transgenic Cry1B/Cry1C Bt cabbage and cauliflower plants for control of lepidopteran pests
In 2003 the Collaboration on Insect Management for Brassicas in Asia and Africa (CIMBAA) public/private partnership selected the Cry1B/Cry1C Bt protein combination as having the potential to provide effective and sustainable control of diamondback moth (DBM), Plutella xylostella. Following transformations and extensive plant selection, insect efficacy trials were undertaken in 2008 to 2010 in north India (Murthal near New Delhi) and south India (near Bengaluru) in large scale screen-house experiments using artificial infestations on the best performing (Elite Event) plant lines and on hybrids produced from them. Plant damage was scored on a scale of 0 (no visible damage) to 4 (plant effectively destroyed). For DBM, cabbage cluster caterpillar (Crocidolomia binotalis), cabbage webworm (Hellula undalis) and semi-looper (Trichoplusia ni) there was zero insect survival and a zero damage score on the Elite Event lines and on their hybrids, while control plants had 50 to 100% insect survival (depending on species, life stage and trials) and damage scores of 3.3 to 4. Cabbage white (Pieris brassicae) and common army worm (Spodoptera litura) showed some larval survival and damage scores up to 1.4 (especially in early trials) but no survival to pupation. Screening of DBM populations worldwide (inc. 18 populations for Cry1B and 13 for Cry1C from India) showed mean LC50s close to that of international susceptible strains. To date F2 screening has not identified the presence of resistance genes in DBM in the field. Cry1B resistance was slowly developed artificially in the laboratory but 1C resistance and resistance to the Cry1B/1C combination was harder to develop and had higher fitness costs. The ‘resistant’ lines showed some extended survival of stunted DBM larvae on dual gene Bt plants but no survival to pupation. There was no cross-resistance between Cry1B and Cry1C. Resistance to both genes was autosomal and recessive. Beneficial insects were demonstrated to have the potential to provide additional mortality on rare surviving insects in Bt fields. Aphids were well controlled for the first 40 days post-transplanting using imidacloprid pelleted onto seed and, if necessary, by 1-2 Verticillium lecanii sprays thereafter. Surviving S. litura and Helicoverpa armigera in Bt sprayed fields were well controlled by one or two application
The effect of loading direction and Sn alloying on the deformation modes of Zr: An in-situ neutron diffraction study
Deformation modes (slip and twining) in a strongly textured model hcp alloy system (Zr–Sn) have been investigated using in-situ neutron diffraction and deformation along with complementary electron microscopy. Analysis of the evolution of the intergranular strain evolutions and intensity of specific reflections from neutron diffraction show differential influence of Sn on the extent of twinning too, depending on the deformation direction. While Sn displayed very noticeable influence on twin activity when samples were compressed along a direction that predominantly activates prismatic slip, this effect was not seen when samples were compressed along other different directions. These experimental observations were successfully simulated using a CPFE (crystal plasticity finite element) model that incorporates composition sensitive CRSS (critical resolved shear stress) for slip and composition insensitive CRSS activation of twinning. The success of the CPFE model in capturing the experimental observations with respect to twin evolution suggests that the twinning in Zr is chiefly governed by the initial crystallographic texture and the associated intergranular stress state generated during plastic deformation
Population and fertility by age and sex for 195 countries and territories, 1950–2017: a systematic analysis for the Global Burden of Disease Study 2017
Background: Population estimates underpin demographic and epidemiological research and are used to track progress on numerous international indicators of health and development. To date, internationally available estimates of population and fertility, although useful, have not been produced with transparent and replicable methods and do not use standardised estimates of mortality. We present single-calendar year and single-year of age estimates of fertility and population by sex with standardised and replicable methods. Methods: We estimated population in 195 locations by single year of age and single calendar year from 1950 to 2017 with standardised and replicable methods. We based the estimates on the demographic balancing equation, with inputs of fertility, mortality, population, and migration data. Fertility data came from 7817 location-years of vital registration data, 429 surveys reporting complete birth histories, and 977 surveys and censuses reporting summary birth histories. We estimated age-specific fertility rates (ASFRs; the annual number of livebirths to women of a specified age group per 1000 women in that age group) by use of spatiotemporal Gaussian process regression and used the ASFRs to estimate total fertility rates (TFRs; the average number of children a woman would bear if she survived through the end of the reproductive age span [age 10–54 years] and experienced at each age a particular set of ASFRs observed in the year of interest). Because of sparse data, fertility at ages 10–14 years and 50–54 years was estimated from data on fertility in women aged 15–19 years and 45–49 years, through use of linear regression. Age-specific mortality data came from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 estimates. Data on population came from 1257 censuses and 761 population registry location-years and were adjusted for underenumeration and age misreporting with standard demographic methods. Migration was estimated with the GBD Bayesian demographic balancing model, after incorporating information about refugee migration into the model prior. Final population estimates used the cohort-component method of population projection, with inputs of fertility, mortality, and migration data. Population uncertainty was estimated by use of out-of-sample predictive validity testing. With these data, we estimated the trends in population by age and sex and in fertility by age between 1950 and 2017 in 195 countries and territories. Findings: From 1950 to 2017, TFRs decreased by 49\ub74% (95% uncertainty interval [UI] 46\ub74–52\ub70). The TFR decreased from 4\ub77 livebirths (4\ub75–4\ub79) to 2\ub74 livebirths (2\ub72–2\ub75), and the ASFR of mothers aged 10–19 years decreased from 37 livebirths (34–40) to 22 livebirths (19–24) per 1000 women. Despite reductions in the TFR, the global population has been increasing by an average of 83\ub78 million people per year since 1985. The global population increased by 197\ub72% (193\ub73–200\ub78) since 1950, from 2\ub76 billion (2\ub75–2\ub76) to 7\ub76 billion (7\ub74–7\ub79) people in 2017; much of this increase was in the proportion of the global population in south Asia and sub-Saharan Africa. The global annual rate of population growth increased between 1950 and 1964, when it peaked at 2\ub70%; this rate then remained nearly constant until 1970 and then decreased to 1\ub71% in 2017. Population growth rates in the southeast Asia, east Asia, and Oceania GBD super-region decreased from 2\ub75% in 1963 to 0\ub77% in 2017, whereas in sub-Saharan Africa, population growth rates were almost at the highest reported levels ever in 2017, when they were at 2\ub77%. The global average age increased from 26\ub76 years in 1950 to 32\ub71 years in 2017, and the proportion of the population that is of working age (age 15–64 years) increased from 59\ub79% to 65\ub73%. At the national level, the TFR decreased in all countries and territories between 1950 and 2017; in 2017, TFRs ranged from a low of 1\ub70 livebirths (95% UI 0\ub79–1\ub72) in Cyprus to a high of 7\ub71 livebirths (6\ub78–7\ub74) in Niger. The TFR under age 25 years (TFU25; number of livebirths expected by age 25 years for a hypothetical woman who survived the age group and was exposed to current ASFRs) in 2017 ranged from 0\ub708 livebirths (0\ub707–0\ub709) in South Korea to 2\ub74 livebirths (2\ub72–2\ub76) in Niger, and the TFR over age 30 years (TFO30; number of livebirths expected for a hypothetical woman ageing from 30 to 54 years who survived the age group and was exposed to current ASFRs) ranged from a low of 0\ub73 livebirths (0\ub73–0\ub74) in Puerto Rico to a high of 3\ub71 livebirths (3\ub70–3\ub72) in Niger. TFO30 was higher than TFU25 in 145 countries and territories in 2017. 33 countries had a negative population growth rate from 2010 to 2017, most of which were located in central, eastern, and western Europe, whereas population growth rates of more than 2\ub70% were seen in 33 of 46 countries in sub-Saharan Africa. In 2017, less than 65% of the national population was of working age in 12 of 34 high-income countries, and less than 50% of the national population was of working age in Mali, Chad, and Niger. Interpretation: Population trends create demographic dividends and headwinds (ie, economic benefits and detriments) that affect national economies and determine national planning needs. Although TFRs are decreasing, the global population continues to grow as mortality declines, with diverse patterns at the national level and across age groups. To our knowledge, this is the first study to provide transparent and replicable estimates of population and fertility, which can be used to inform decision making and to monitor progress. Funding: Bill & Melinda Gates Foundation
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Not AvailableGlobally, water deficit is one of the major constraints in chickpea (Cicer arietinum L.) production due to substantial reduction in photosynthesis. Photorespiration often enhances under stress thereby protecting the photosynthetic apparatus from photoinhibition. Application of bioregulators is an alternative to counter adverse effects of water stress. Thus, in order to analyze the role of bioregulators in protecting the photosynthetic machinery under water stress, we performed an experiment with two contrasting chickpea varieties, i.e., Pusa 362 (Desi type) and Pusa 1108 (Kabuli type). Water deficit stress was imposed at the vegetative stage by withholding water. Just prior to exposure to water stress, plants were pretreated with thiourea (1,000 mg L−1), benzyladenine (40 mg L−1), and thidiazuron (10 mg L−1). Imposed water deficit decreased relative water content (RWC), photosynthetic rate (PN), quantum efficiency of PSII (Fv/Fm), and enhanced lipid peroxidation (LPO). However, bioregulator application maintained higher RWC, PN, Fv/Fm, and lowered LPO under water stress. Expression of Rubisco large subunit gene (RbcL) was low under water stress both in the Kabuli and Desi type. However, bioregulators strongly induced its expression. Although poor expression of two important photorespiratory genes, i.e., glycolate oxidase and glycine decarboxylase H subunit, was observed in Desi
chickpea under imposed stress, bioregulators in general and cytokinins in particular strongly induced their expression. This depicts that the application of bioregulators protected the photosynthetic machinery by inducing the expression of RbcL and photorespiratory genes during water deficit stress.Not Availabl
Walnut shells: food processing waste from western Himalayan state of Himachal Pradesh as an excellent source for production of activated carbon with highly acidic surface
Walnut shells: food processing waste from western Himalayan state of Himachal Pradesh as an excellent source for production of activated carbon with highly acidic surface
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Not AvailableAntioxidant defense system in plants against abiotic stressNot Availabl
Novel Defects in Al-Pd-Fe Complex Metallic Alloys: A Micromechanical Modelling Approach
Transmission electron microscopy investigations have revealed that in the face centred complex metallic alloy of C-2-Al-Pd-Fe the dislocations mediating plastic flow are decorated by localized regions of body centred structure in the compressive part of their strain field thus forming composite defects We calculated the properties of these defects using a micromechanical model The Eshelby method was employed to estimate the energies involved in the formation of such defects in the face-centred C-2 phase We could reproduce the experimentally observed features of the defects in terms of their size and spatial configuration The model describes a unique mechanism of a non-equilibnum defect i e a dislocation being stabilized by the formation and interaction with another non-equilibrium defect i e a nanometre sized inclusion of different structure (C) 2010 Elsevier Ltd All rights reserve