131 research outputs found

    Perception of solar UV radiation and blue light by plants : photoreceptors, transcriptome and environmental acclimation

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    Solar UV-B radiation (290–315 nm), UV-A radiation (315–400 nm), and blue light (400–500 nm) regulate multiple aspects of plant growth and development, and these are mediated by different photoreceptors. In plants, UVR8 is described as a UV-B photoreceptor, while cryptochromes (CRYs) are described as UV-A/blue photoreceptors, based on their absorption maxima and action spectra. However, these photoreceptors are also sensitive to other wavelengths outside the wavelengths of maximum absorption. Based on this property, their roles could differ in full-spectrum sunlight than those reported from experiments performed in controlled environments. In sunlight, both UV-B and UV-A/blue photoreceptors are simultaneously activated, and there is a possibility that their signaling pathways interact. However, an interaction between UVR8 and CRYs regulating transcriptome-wide responses remained unexplored. Furthermore, persistent high solar irradiance is often followed by drought in the field, and studies have indicated that UV and drought interact to regulate plant physiological responses. However, an interaction for metabolic and transcript abundance responses has not been well-described. These gaps in knowledge are addressed in my thesis through three main aims: (1) to identify the individual roles of UVR8 and CRYs in the perception of solar UV-B, short-wave UV-A (315–350 nm, UV-Asw), long-wave UV-A (350–400 nm, UV-Alw) radiation, and blue light by plants, (2) to test the interaction between UVR8 and CRYs under solar UV radiation, and (3) to determine if pre-exposure to solar UV radiation could provide acclimation to subsequent drought stress in plants. To achieve the first two aims, I used Arabidopsis thaliana wild type and mutants impaired in UVR8 and CRYs photoreceptors and exposed them to different ranges of wavelengths of solar or simulated solar UV radiation and blue light under optical filters. To achieve the third aim, I used two accessions of Medicago truncatula (Jemalong A17 and F83005-5). I exposed them to solar UV radiation using optical filters and subjected them to drought stress by restricting watering in a factorial experiment. The results indicated that UVR8 mediates the perception of both UV-B and UV-Asw radiation. In contrast, CRYs mediate the perception of UV-Alw radiation and blue light. A further novel finding is that UVR8 and CRYs interact antagonistically to regulate transcriptome-wide responses under UV-B and UV-Asw radiation. My thesis also provides evidence that UV-B+UV-Asw radiation and mild drought can interact positively to trigger acclimation through an increase in epidermal UV screening in the drought-intolerant accession, F83005-5, and through an increase in transcript abundance of CHALCONE SYNTHASE in the moderately drought-tolerant accession, Jemalong A17. Furthermore, all three studies showed a distinct response to solar or simulated solar UV-B+UV-Asw and UV-Alw radiation, suggesting a need to split UV-A into short and long wavelengths for future studies on UV-A radiation.Auringon UV-B-säteily (290–315 nm), UV-A-säteily (315–400 nm) ja sininen valo (400–500 nm) säätelevät monia kasvien kasvuun ja kehitykseen liittyviä asioita, jotka välittyvät erilaisten fotoreseptoreiden kautta. Kasvien UVR8 kuvataan UV-B-fotoreseptoriksi, kun taas kryptokromit (CRY) kuvataan UV-A-säteilyn/sinisen valon fotoreseptoreiksi niiden absorptiomaksimien ja vaikutusspektrien perusteella. Nämä fotoreseptorit ovat kuitenkin herkkiä myös muille aallonpituuksille, jotka ovat niiden maksimaalisen absorption aallonpituuksien ulkopuolella, ja näiden ominaisuuksien perusteella niiden toiminta saattaa poiketa auringonvalon laajan spektrin alla, verrattuna tilanteisiin joista on raportoitu kontrolloiduissa ympäristöissä suoritetuista kokeista. Auringonvalossa sekä UV-B- että UV-A-säteilyn/sinisen valon fotoreseptorit aktivoituvat samanaikaisesti ja on mahdollista, että niiden signalointireitit ovat vuorovaikutuksessa. UVR8 ja CRY -fotoreseptoreiden välistä vuorovaikutusta, joka säätelee transkriptometrin laajuisia vasteita, ei kuitenkaan ole tutkittu. Lisäksi, pitkäkestoista korkeaa auringonsäteilyn määrää seuraa usein kuivuus, ja tutkimukset ovat osoittaneet, että UV ja kuivuus säätelevät kasvien fysiologisia vasteita vuorovaikutteisesti. Metabolisten ja transkriptien vasteiden vuorovaikutusta ei kuitenkaan ole kuvattu tarkasti. Käsittelen näitä kysymyksiä väitöskirjassani kolmen päätavoitteen kautta: (1) tunnistaa UVR8 ja CRY-fotoreseptoreiden roolit auringon UV-B-säteilyn, lyhytaaltotoisen UV-A-säteilyn (315–350 nm, UV-Asw), pitkäaaltoisen UV-A-säteilyn (350–400 nm, UV-Alw) ja sinisen valon havainnoinnissa, (2) testata UVR8 ja CRY-fotoreseptoreiden välistä vuorovaikutusta auringon UV-säteilyn alla ja (3) määrittää, voiko kasvien altistus auringon UV-säteilylle edesauttaa sopeutumista myöhemmin seuraavaan kuivuusstressiin. Kahden ensimmäisen tavoitteen saavuttamiseksi käytin sekä Arabidopsis villityyppiä että UVR8 ja CRY-fotoreseptorimutantteja, ja altistin ne erilaisille auringonsäteilyn aallonpituusalueille tai simuloidulle auringon UV-säteilylle ja siniselle valolle optisten suodattimien alla. Kolmannen tavoitteen saavuttamiseksi käytin alkuperältään erilaisia Medicago truncatula-kasveja (Jemalong A17 ja F83005-5). Altistin kasvit auringon UV-säteilylle käyttämällä optisia suodattimia ja altistin kasvit kuivuusstressille rajoittamalla kastelua faktorikokeessa. Tulokset osoittivat, että UVR8 välittää sekä UV-B- että UV-Asw-säteilyn havaitsemista. Sen sijaan CRY:t välittävät UV-Alw-säteilyn ja sinisen valon havaitsemista. Lisäksi uusi havainto on, että UVR8 ja CRY:t ovat vuorovaikutuksessa antagonistisesti, säädellen transkriptometrin laajuisia vasteita UV-B- ja UV-Asw-säteilyyn. Väitöskirjani tarjoaa myös todisteita siitä, että UV-B + UV-Asw-säteily ja lievä kuivuus voivat olla positiivisessa vuorovaikutuksessa ja käynnistää sopeutumista lisäämällä epidermaalisen UV-suojauksen määrää kuivuutta huonosti kestävillä F83005-5 -alkuperän kasveilla, ja lisäämällä CHS:n transkriptiota kohtalaisesti kuivuutta sietävillä Jemalong A17 -alkuperän kasveilla. Lisäksi kaikki kolme tutkimusta osoittivat erilaisen vasteen UV-B + UV-Asw ja UV-Alw-säteilylle sekä auringonsäteilyn että simuloidun säteilyn alla, mikä viittaa tarpeeseen jakaa UV-A lyhyisiin ja pitkiin aallonpituuksiin tulevia UV-A-säteilyyn liittyviä tutkimuksia varten

    Production and optimization of Pectinase enzyme using Aspergillus niger strains in Solid State fermentation

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    Solid state fermentation was carried out with 4 fungal strains, obtained from different sources. Among 4 isolates Aspergillus niger, ATCC 16404 was found as effective pectinase producer. Maximum enzymatic activity (1.62 IU ml-1) was observed after 7 days incubation at 30‹C temperature in 250 ml Erlenmeyer conical flask. In this study 1% dextrose was used as arbon source, although citric acid as a carbon source showed better result (2.73 IU ml-1) but starch was not cost effective. As a substrate, combination of wheat bran and fresh mosambi, orange and lemon peel in ratio of 9:1:1:1 showed good result (5.38 IU ml-1) in solid state culture. Addition of 5% pectin was found to increase the enzyme production as (3.38 IU ml-1) Pectinase production was optimum in 65% moisture thus the wild strain Aspergillus niger ATCC16404 has outstanding pectinase producing capability at 30.C in 65% moisture content for 7 days of incubation in solid state fermentation

    Knowledge attitude and practice of contraception in Barabanki district of Uttar Pradesh: how far are we from meeting the unmet needs of contraception

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    Background: Barabanki one of the most populous districts of Uttar Pradesh with population growth rate being much higher than the national population growth rate. The objective of this study was to gain the knowledge about awareness and contraceptive practices in married women residing in Barabanki. To identify socio-demographic factors associated with unmet needs for contraceptionand also to ascertain the participation of husband in family planning.Methods: A cross sectional study was conducted in outpatient department of Obstetrics Gynecology and Department of Pediatrics in Medical college hospital in Barabanki. 144 females were enrolled in the study during the study period of one year. They were interviewed on the basis of a pre-structured proforma. Data obtained was then analyzed.Results: A total 144 women in the age group 18-45 years participated in the study of which 53% had knowledge of contraception. More than two thirds were not using any form of contraception. The most common method of contraception was barrier method followed by Depot medroxy progesterone acetate. Copper T was least used mode of contraception. The most common source of knowledge regarding contraception was from electronic media followed by friends and family. The most common reason behind the absence of contraception was lack of knowledge of contraception and husband disapproval.Conclusions: Poor knowledge of contraception led to decreased usage of contraceptive measures. Husband participation is virtually absent in family planning leading to high fertility. In order to make our family planning programs successful we must incorporate media for wider coverage to increase awareness and husbands for better implementation

    Perception of solar UV radiation by plants : photoreceptors and mechanisms

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    About 95% of the ultraviolet (UV) photons reaching the Earth's surface are UV-A (315-400 nm) photons. Plant responses to UV-A radiation have been less frequently studied than those to UV-B (280-315 nm) radiation. Most previous studies on UV-A radiation have used an unrealistic balance between UV-A, UV-B, and photosynthetically active radiation (PAR). Consequently, results from these studies are difficult to interpret from an ecological perspective, leaving an important gap in our understanding of the perception of solar UV radiation by plants. Previously, it was assumed UV-A/blue photoreceptors, cryptochromes and phototropins mediated photomorphogenic responses to UV-A radiation and "UV-B photoreceptor" UV RESISTANCE LOCUS 8 (UVR8) to UV-B radiation. However, our understanding of how UV-A radiation is perceived by plants has recently improved. Experiments using a realistic balance between UV-B, UV-A, and PAR have demonstrated that UVR8 can play a major role in the perception of both UV-B and short-wavelength UV-A (UV-A(sw), 315 to similar to 350 nm) radiation. These experiments also showed that UVR8 and cryptochromes jointly regulate gene expression through interactions that alter the relative sensitivity to UV-B, UV-A, and blue wavelengths. Negative feedback loops on the action of these photoreceptors can arise from gene expression, signaling crosstalk, and absorption of UV photons by phenolic metabolites. These interactions explain why exposure to blue light modulates photomorphogenic responses to UV-B and UV-A(sw) radiation. Future studies will need to distinguish between short and long wavelengths of UV-A radiation and to consider UVR8's role as a UV-B/UV-A(sw) photoreceptor in sunlight.Peer reviewe

    Variations of great saphenous vein: a cadaveric study in central Indian population

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    Background: Variations are more commonly seen in venous system as compared to arterial system. Varicosities are more commonly seen in the superficial veins of lower limbs.Methods: In the present study, thirty lower limbs were dissected superficially to study the course, tributaries and perforators of great saphenous vein. After exposing the vein, we took various measurements from saphenofemoral junction to the origin of various tributaries and perforators. Pattern of duplications were also reported.Results: The mean distance of tributaries and perforators were compared with the previous literature available. Patterns of duplication were also reported.Conclusions: Study of variations of great saphenous vein would be of immense help in planning varicose vein treatment and coronary artery bypass procedures where it is used as autograft. Therefore, the study will be helpful for surgeons, cardiologist and interventional radiologist

    Correlations and Organisational Effects of Compensation and Benefits, Job Satisfaction, Career Satisfaction and Job Stress in Public and Private Hospitals in Lucknow, India

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    The present study compares the organisational effect of compensation and benefits in public and private hospitals. It was observed that private hospital employees were more satisfied with their compensation and benefits as compared to the employees of government hospitals. Furthermore, the employees who were satisfied with their compensation and benefits were also found to be satisfied with their jobs. Abbreviations: HR – Human Resources

    National political economy of climate funds: case studies of the PPCR and the SREP

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    Over the last 20 years international climate finance has increased in scale, developed a complex architecture and drawn in a wide range of actors and institutions. Countries have made use of increasingly diverse sources of funding, financial instruments and intermediaries (Rai et al. 2015a; Kaur et al. 2014). Funding comes from both public and private sources, and may be channelled to developing countries in a variety of ways. These include funding mechanisms set up under the UNFCCC, as well as a range of multiand bilateral channels operating outside the UNFCCC (Rai et al. 2015b). At the same time, recent developments in climate policy are driving the integration of the mitigation and adaptation agendas. The increase in funds and diversification of funding mechanisms has led to changes in priorities and power relations at the national level. The picture is complex, given the interaction between the general international context, with its influence on climate finance incentives and governance, and the specific political environments of individual countries. While analysis of the international context has been plentiful (see, for example, Paterson and Grubb 1992; Luterbacher and Sprinz 2001; Aldy et al. 2003; Adger et al. 2006; Nakhooda and Norman 2014), there is a need for greater attention to be paid to this interaction, and to ask how international initiatives are being translated and reformulated in national contexts (Tanner and Allouche 2011; Naess et al. 2015). In this chapter we address this question through case studies of the Pilot Program for Climate Resilience (PPCR) and the Scaling Up Renewable Energy Program (SREP) as they operate in Bangladesh, Ethiopia and Nepal. These two programmes represent global funding initiatives supporting the climate adaptation and climate mitigation agendas, respectively; both are part of the group of non-UNFCCC multilateral funds managed by the World Bank known as the Climate Investment Funds

    Political Economy of International Climate Finance: Navigating Decisions in PPCR and SREP

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    This working paper explores how countries can build their own 'climate finance readiness' by understanding their internal political economy and use that understanding to steer consensus-based decisions on climate finance investments. For climate finance to be effective, national leaders must build shared commitments. This involves considering the arguments, incentives and power dynamics at play to ensure priorities are more equitable and representative of a broader group of stakeholders. Doing so will also help to reduce the risk of implementation delays. This paper uses case studies from Bangladesh, Ethiopia and Nepal to explore how narratives and incentives within the political economy drive climate investment outcomes under the Pilot Programme for Climate Resilience (PPCR) and the Scaling up Renewable Energy Programme (SREP). It draws from broader analysis of the discourses around these investments, including 80 interviews with government; multilateral development banks (MDBs) and other stakeholders

    Interference of anti-nuclear antibodies on determination of anti-neutrophil cytoplasmic antibodies in patients suspected of vasculitis: a case series

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    Anti-neutrophil cytoplasmic antibodies (ANCA) are mainly associated with medium and small vessel vasculitis. Two main methodologies currently available for detection of these antibodies are indirect immunofluorescence (IIF) and monospecific proteinase 3 (PR3) and myeloperoxidase (MPO) based immunoassays. However, well-defined guidelines regarding mode of testing for ANCA in laboratories still don’t exist, leading to problems in diagnosis and further patient management. Anti-neutrophil cytoplasmic antibodies testing by IIF and enzyme linked immunosorbent assay (ELISA) often pose a significant challenge in diseases other than vasculitis and in overlapping autoimmune conditions. Anti-neutrophil cytoplasmic antibodies reporting by IIF can be challenging in certain circumstances. This case series aims to discuss four cases with probable interference of anti-nuclear antibodies (ANA) during ANCA testing by IIF resulting in ANCA false positivity. All four cases on subsequent reflex testing by line immunoassay (LIA) for PR3, MPO and glomerular basement membrane (GBM) antigens proved otherwise. While analysing for the presence of ANCA by IIF, the possible interference of ANA leading to a false positive ANCA result should be kept in mind and alternative methods of testing like ELISA, extended granulocyte based IIF assays with MPO and PR3 coated beads, etc., should also be advised. Probability of atypical ANCA in diseases other than vasculitis should also be considered in case of ambiguous results

    Model-Based Inverse Reinforcement Learning from Visual Demonstrations

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    Scaling model-based inverse reinforcement learning (IRL) to real robotic manipulation tasks with unknown dynamics remains an open problem. The key challenges lie in learning good dynamics models, developing algorithms that scale to high-dimensional state-spaces and being able to learn from both visual and proprioceptive demonstrations. In this work, we present a gradient-based inverse reinforcement learning framework that utilizes a pre-trained visual dynamics model to learn cost functions when given only visual human demonstrations. The learned cost functions are then used to reproduce the demonstrated behavior via visual model predictive control. We evaluate our framework on hardware on two basic object manipulation tasks.Comment: Accepted at the 4th Conference on Robotic Learning (CoRL 2020), Cambridge MA, US
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