200 research outputs found
Partial Root-Zone Drying of Olive (Olea europaea var. "Chetoui") Induces Reduced Yield under Field Conditions
The productivity of olive trees in arid and semi-arid environments is closely linked to irrigation. It is necessary to improve the efficiency of irrigation techniques to optimise the amount of olive fruit produced in relation to the volume of water used. Partial root-zone drying (PRD) is a water saving irrigation technique that theoretically allows the production of a root-to-shoot signal that modifies the physiology of the above-ground parts of the plant; specifically reducing stomatal conductance (gs) and improving water use efficiency (WUE). Partial root-zone drying has been successfully applied under field conditions to woody and non-woody crops; yet the few previous trials with olive trees have produced contrasting results. Thirty year-old olive trees (Olea europaea āvar. Chetouiā) in a Tunisian grove were exposed to four treatments from May to October for three-years: ācontrolā plants received 100% of the potential evapotranspirative demand (ETc) applied to the whole root-zone; āPRD100ā were supplied with an identical volume of water to the control plants alternated between halves of the root-zone every ten-days; āPRD50ā were given 50% of ETc to half of the root-system, and; ārain-fedā plants received no supplementary irrigation. Allowing part of the root-zone to dry resulted in reduced vegetative growth and lower yield: PRD100 decreased yield by ~47% during productive years. During the less productive years of the alternate bearing cycle, irrigation had no effect on yield; this suggests that withholding of water during āoff-yearsā may enhance the effectiveness of irrigation over a two-year cycle. The amount and quality of oil within the olive fruit was unaffected by the irrigation treatment. Photosynthesis declined in the PRD50 and rain-fed trees due to greater diffusive limitations and reduced biochemical uptake of CO2. Stomatal conductance and the foliar concentration of abscisic acid (ABA) were not altered by PRD100 irrigation, which may indicate the absence of a hormonal root-to-shoot signal. Rain-fed and PRD50 treatments induced increased stem water potential and increased foliar concentrations of ABA, proline and soluble sugars. The stomata of the olive trees were relatively insensitive to super-ambient increases in [CO2] and higher [ABA]. These characteristics of āhydro-passiveā stomatal behaviour indicate that the āChetouiā variety of olive tree used in this study lacks the physiological responses required for the successful exploitation of PRD techniques to increase yield and water productivity. Alternative irrigation techniques such as partial deficit irrigation may be more suitable for āChetouiā olive production.This work was supported by the Ministero dellāIstruzione, dellāUniversitĆ e della Ricerca of Italy: PRIN 2010ā2011 āPRO-ROOTā and Progetto Premiale 2012 āAquaā. MH acknowledges funding from a Marie Curie IEF (2010ā275626). We are grateful to Dr Mohamed Ghrab (Olive Tree Institute) for technical assistance and scientific discussion. The comments of Georgios Koubouris (Hellenic Agricultural Organization) and two anonymous reviewers significantly improved this manuscript
Opportunities and limitations of crop phenotyping in southern european countries
ReviewThe Mediterranean climate is characterized by hot dry summers and frequent droughts.
Mediterranean crops are frequently subjected to high evapotranspiration demands,
soil water deficits, high temperatures, and photo-oxidative stress. These conditions
will become more severe due to global warming which poses major challenges to the
sustainability of the agricultural sector in Mediterranean countries. Selection of crop
varieties adapted to future climatic conditions and more tolerant to extreme climatic events
is urgently required. Plant phenotyping is a crucial approach to address these challenges.
High-throughput plant phenotyping (HTPP) helps to monitor the performance of improved
genotypes and is one of the most effective strategies to improve the sustainability of
agricultural production. In spite of the remarkable progress in basic knowledge and
technology of plant phenotyping, there are still several practical, financial, and political
constraints to implement HTPP approaches in field and controlled conditions across the
Mediterranean. The European panorama of phenotyping is heterogeneous and integration
of phenotyping data across different scales and translation of āphytotron researchā to the
field, and from model species to crops, remain major challenges. Moreover, solutions
specifically tailored to Mediterranean agriculture (e.g., crops and environmental stresses)
are in high demand, as the region is vulnerable to climate change and to desertification
processes. The specific phenotyping requirements of Mediterranean crops have not
yet been fully identified. The high cost of HTPP infrastructures is a major limiting factor,
though the limited availability of skilled personnel may also impair its implementation in
Mediterranean countries. We propose that the lack of suitable phenotyping infrastructures
is hindering the development of new Mediterranean agricultural varieties and will negatively
affect future competitiveness of the agricultural sector. We provide an overview of the
heterogeneous panorama of phenotyping within Mediterranean countries, describing the
state of the art of agricultural production, breeding initiatives, and phenotyping capabilities
in five countries: Italy, Greece, Portugal, Spain, and Turkey. We characterize some of the main impediments for development of plant phenotyping in those countries and identify
strategies to overcome barriers and maximize the benefits of phenotyping and modeling
approaches to Mediterranean agriculture and related sustainabilityinfo:eu-repo/semantics/publishedVersio
Effect of Ventilation Rate on Instilled Surfactant Distribution in the Pulmonary Airways of Rats
Liquid can be instilled into the pulmonary airways during medical procedures such as surfactant replacement therapy, partial liquid ventilation, and pulmonary drug delivery. For all cases, understanding the dynamics of liquid distribution in the lung will increase the efficacy of treatment. A recently developed imaging technique for the study of real-time liquid transport dynamics in the pulmonary airways was used to investigate the effect of respiratory rate on the distribution of an instilled liquid, surfactant, in a rat lung. Twelve excised rat lungs were suspended vertically, and a single bolus (0.05 ml) of exogenous surfactant (Survanta, Ross Laboratories, Columbus, OH) mixed with radiopaque tracer was instilled as a plug into the trachea. The lungs were ventilated with a 4-ml tidal volume for 20 breaths at one of two respiratory rates: 20 or 60 breaths/min. The motion of radiodense surfactant was imaged at 30 frames/s with a microfocal X-ray source and an image intensifier. Dynamics of surfactant distribution were quantified for each image by use of distribution statistics and a homogeneity index. We found that the liquid distribution depended on the time to liquid plug rupture, which depends on ventilation rate. At 20 breaths/min, liquid was localized in the gravity-dependent region of the lung. At 60 breaths/min, the liquid coated the airways, providing a more vertically uniform liquid distribution
Challenges and solutions to system-wide use of precision oncology as the standard of care paradigm
The personalised oncology paradigm remains challenging to deliver despite technological advances in genomics-based identification of actionable variants combined with the increasing focus of drug development on these specific targets. To ensure we continue to build concerted momentum to improve outcomes across all cancer types, financial, technological and operational barriers need to be addressed. For example, complete integration and certification of the āmolecular tumour boardā into āstandard of careā ensures a unified clinical decision pathway that both counteracts fragmentation and is the cornerstone of evidence-based delivery inside and outside of a research setting. Generally, integrated delivery has been restricted to specific (common) cancer types either within major cancer centres or small regional networks. Here, we focus on solutions in real-world integration of genomics, pathology, surgery, oncological treatments, data from clinical source systems and analysis of whole-body imaging as digital data that can facilitate cost-effectiveness analysis, clinical trial recruitment, and outcome assessment. This urgent imperative for cancer also extends across the early diagnosis and adjuvant treatment interventions, individualised cancer vaccines, immune cell therapies, personalised synthetic lethal therapeutics and cancer screening and prevention. Oncology care systems worldwide require proactive step-changes in solutions that include inter-operative digital working that can solve patient centred challenges to ensure inclusive, quality, sustainable, fair and cost-effective adoption and efficient delivery. Here we highlight workforce, technical, clinical, regulatory and economic challenges that prevent the implementation of precision oncology at scale, and offer a systematic roadmap of integrated solutions for standard of care based on minimal essential digital tools. These include unified decision support tools, quality control, data flows within an ethical and legal data framework, training and certification, monitoring and feedback. Bridging the technical, operational, regulatory and economic gaps demands the joint actions from public and industry stakeholders across national and global boundaries
The correlation between reading and mathematics ability at age twelve has a substantial genetic component
Dissecting how genetic and environmental influences impact on learning is helpful for maximizing numeracy and literacy. Here we show, using twin and genome-wide analysis, that there is a substantial genetic component to childrenās ability in reading and mathematics, and estimate that around one half of the observed correlation in these traits is due to shared genetic effects (so-called Generalist Genes). Thus, our results highlight the potential role of the learning environment in contributing to differences in a childās cognitive abilities at age twelve
Hen Harrier Circus cyaneus nest sites on the Isle of Mull are associated with habitat mosaics and constrained by topography
This is an Accepted Manuscript of an article published by Taylor & Francis in Bird Study on 07/02/2018, available online: http://www.tandfonline.com/doi/full/10.1080/00063657.2017.1421611Capsule: Hen Harrier on the Isle of Mull, UK, are associated with habitat mosaics consisting of moorland, scrub and forestry but avoid grazed land, suggesting that forested habitats could be managed sympathetically for Hen Harrier in the future should the current UK population increase. Aims: To use distribution modelling to investigate nesting habitat associations using a long term dataset for Hen Harrier on Mull. Methods: We develop area-interaction models using a LASSO penalty to explore the distribution of 102 Hen Harrier nest sites in relation to habitat and topography. Our model is then successfully validated in tests using data for 70 nest sites from subsequent years. Results: Our model is effective in predicting suitable areas for Hen Harrier nest sites and indicates that Hen Harriers on Mull are found in habitat mosaics below 200 m asl. Hen Harrier nest intensity is positively associated with increasing proportions of moorland and scrub, open canopy forestry and closed canopy forestry. Nest intensity is negatively associated with increasing proportions of grazed land. Conclusion: Hen Harrier avoid grazed areas but are relatively tolerant of other habitat combinations. These findings are supported by previous observations of Hen Harrier habitat use and have implications for the recovery of some Hen Harrier SPA populations and future forest management. Open canopy forest and forest mosaics could potentially be incorporated into landscape-scale conservation plans for Hen Harriers using the population in Mull as an example
XUE. Molecular inventory in the inner region of an extremely irradiated Protoplanetary Disk
We present the first results of the eXtreme UV Environments (XUE) James Webb
Space Telescope (JWST) program, that focuses on the characterization of planet
forming disks in massive star forming regions. These regions are likely
representative of the environment in which most planetary systems formed.
Understanding the impact of environment on planet formation is critical in
order to gain insights into the diversity of the observed exoplanet
populations. XUE targets 15 disks in three areas of NGC 6357, which hosts
numerous massive OB stars, among which some of the most massive stars in our
Galaxy. Thanks to JWST we can, for the first time, study the effect of external
irradiation on the inner ( au), terrestrial-planet forming regions of
proto-planetary disks. In this study, we report on the detection of abundant
water, CO, CO, HCN and CH in the inner few au of XUE 1, a highly
irradiated disk in NGC 6357. In addition, small, partially crystalline silicate
dust is present at the disk surface. The derived column densities, the
oxygen-dominated gas-phase chemistry, and the presence of silicate dust are
surprisingly similar to those found in inner disks located in nearby,
relatively isolated low-mass star-forming regions. Our findings imply that the
inner regions of highly irradiated disks can retain similar physical and
chemical conditions as disks in low-mass star-forming regions, thus broadening
the range of environments with similar conditions for inner disk rocky planet
formation to the most extreme star-forming regions in our Galaxy.Comment: Accepted for publication in ApJ Letters. 20 pages, 7 figure
Silencing Nociceptor Neurons Reduces Allergic Airway Inflammation
Lung nociceptors initiate cough and bronchoconstriction. To elucidate if these fibers also contribute to allergic airway inflammation, we stimulated lung nociceptors with capsaicin and observed increased neuropeptide release and immune cell infiltration. In contrast, ablating Nav1.8(+) sensory neurons or silencing them with QX-314, a charged sodium channel inhibitor that enters via large-pore ion channels to specifically block nociceptors, substantially reduced ovalbumin- or house-dust-mite-induced airway inflammation and bronchial hyperresponsiveness. We also discovered that IL-5, a cytokine produced by activated immune cells, acts directly on nociceptors to induce the release of vasoactive intestinal peptide (VIP). VIP then stimulates CD4(+) and resident innate lymphoid type 2 cells, creating an inflammatory signaling loop that promotes allergic inflammation. Our results indicate that nociceptors amplify pathological adaptive immune responses and that silencing these neurons with QX-314 interrupts this neuro-immune interplay, revealing a potential new therapeutic strategy for asthma
Resolvin D2 is a potent regulator of leukocytes and controls microbial sepsis
National Institutes of Health grants GM-38765 and P50-DE016191 (C.N.S.), Welcome Trust Programme grant 086867/Z/08/Z (R.J.F. and M.P.) and Project grant 085903/Z/08 (R.J.F.) and Arthritis Research Campaign UK fellowships 18445 and 18103 (to L.V.N. and D.C., respectively). M.S. received a National Research Service Award from the NHLBI (HL087526)
- ā¦