19 research outputs found
A novel risk factor associated with colonization by Carbapenemase-Producing Enterobacteriaceae: Use of Proton Pump Inhibitors in addition to Antimicrobial Treatment
published_or_final_versio
Early Diagnosis of Vegetation Health From High-Resolution Hyperspectral and Thermal Imagery: Lessons Learned From Empirical Relationships and Radiative Transfer Modelling
[Purpose of Review] We provide a comprehensive review of the empirical and modelling approaches used to quantify the radiation–vegetation interactions related to vegetation temperature, leaf optical properties linked to pigment absorption and chlorophyll fluorescence emission, and of their capability to monitor vegetation health. Part 1 provides an overview of the main physiological indicators (PIs) applied in remote sensing to detect alterations in plant functioning linked to vegetation diseases and decline processes. Part 2 reviews the recent advances in the development of quantitative methods to assess PI through hyperspectral and thermal images.[Recent Findings] In recent years, the availability of high-resolution hyperspectral and thermal images has increased due to the extraordinary progress made in sensor technology, including the miniaturization of advanced cameras designed for unmanned aerial vehicle (UAV) systems and lightweight aircrafts. This technological revolution has contributed to the wider use of hyperspectral imaging sensors by the scientific community and industry; it has led to better modelling and understanding of the sensitivity of different ranges of the electromagnetic spectrum to detect biophysical alterations used as early warning indicators of vegetation health.[Summary] The review deals with the capability of PIs such as vegetation temperature, chlorophyll fluorescence, photosynthetic energy downregulation and photosynthetic pigments detected through remote sensing to monitor the early responses of plants to different stressors. Various methods for the detection of PI alterations have recently been proposed and validated to monitor vegetation health. The greatest challenges for the remote sensing community today are (i) the availability of high spatial, spectral and temporal resolution image data; (ii) the empirical validation of radiation–vegetation interactions; (iii) the upscaling of physiological alterations from the leaf to the canopy, mainly in complex heterogeneous vegetation landscapes; and (iv) the temporal dynamics of the PIs and the interaction between physiological changes.The authors received funding provided by the FluorFLIGHT (GGR801) Marie Curie Fellowship, the QUERCUSAT and ESPECTRAMED projects (Spanish Ministry of Economy and Competitiveness), the Academy of Finland (grants 266152, 317387) and the European Research Council Synergy grant ERC-2013-SyG-610028 IMBALANCE-P.Peer reviewe
Remotely sensed carotenoid dynamics improve modelling photosynthetic phenology in conifer and deciduous forests
This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordDetecting the phenology of photosynthesis, which conveys the length of the growing season, is key for terrestrial ecosystem models to constrain total annual carbon uptake and estimate gross primary productivity (GPP). However, some of the vegetation indices that are widely used for modelling GPP lack the ability to represent changes in the magnitude of photosynthesis, leading to errors in detecting phenology and large uncertainties. Crucially, remotely sensed vegetation indices such as the photochemical reflectance index (PRI) and chlorophyll/carotenoid index (CCI) can detect changes in foliar carotenoid composition that represent adjustments in photosynthetic light-use-efficiency (LUE) and changes in phenology. We modeled GPP from remote sensing data using PRI and CCI to represent foliar carotenoid changes as proxies for LUE. GPP values estimated from these PRI and CCI modified LUE models were compared against GPP from eddy covariance flux tower measurements, MODerate Resolution Imaging Spectroradiometer (MODIS) GPP product, conventional meteorological driven LUE-model, and process-based dynamic global vegetation model (ie. JULES) in an evergreen needleleaf and a deciduous broadleaf forest in the Great Lakes region. Overall, and in particular for evergreen needleleaf forests, estimates of start and end of growing season using PRI and CCI LUE-models showed less year-to-year variability than estimates obtained by process-based meteorological models. Although many process-based models provide reasonable estimates of start and end of growing season, our results demonstrate that using regulatory carotenoids and photosynthetic efficiency can improve remote monitoring of the phenology of forest vegetation.NSERCCFIOntario Ministry of Research and InnovationOntario Ministry of Environment, Conservation and ParksNatural Environment Research Council (NERC)Canadian Society of Plant BiologistsUniversity of Toronto Centre for Global Change Scienc
Out-of-school study time and childhood obesity: evidence from Hong Kong’s “Children of 1997” birth cohort
Abstract and Poster PresentationConference Theme: Healthcare Reforms in Comparative Health SystemsThe RACMA/HKCCM International Conference on 'Healthcare Reforms in Comparative Health Systems', Hong Kong, China, 4-6 September 2010
Effect of the hepatitis B core protein C-terminal domain mutations on HBV transcription
Poster Presentations: Viral hepatitis: Hepatitis B & D – experimental: no. THU-181BACKGROUND AND AIMS: The hepatitis B core protein (HBc) is a component of the HBV covalently closed circular DNA (cccDNA) minichromosome, the transcription template of HBV. The HBc C-terminal domain (CTD) contains an arginine-rich region, which has been shown to be responsible for nucleic acid binding and efficient HBV RNA encapsidation and reverse transcription. It has been implicated that HBV transcription is regulated by the association of HBc to cccDNA. However, direct evidence demonstrating the effect of HBc on HBV transcription is lacking. We aimed to study the effect of HBc mutations on HBV transcription using a cccDNA-dependent study system …Link_to_subscribed_fulltex
The challenge of patient empowerment in hand hygiene promotion in health care facilities in Hong Kong
The hepatitis B core protein associates with HBV covalently closed circular DNA via the C-terminal domain and facilitates HBV transcription
Poster Sessio
Role of hepatitis B core protein in HBV transcription and recruitment of histone acetyltransferases to cccDNA minichromosome
The hepatitis B core protein (HBc) has been suggested to interact with covalently closed circular DNA (cccDNA) and regulate hepatitis B virus (HBV) transcription. However, direct evidence is lacking. We aimed to identify the specific HBc region(s) responsible for transcription regulation and its interaction with cccDNA. Seventeen mutants with mutations at the four arginine-rich clusters of the HBc carboxyl-terminal domain (CTD) were created. The effect of HBc mutations on the levels of HBV DNA, RNA, and hepatitis B surface antigen (HBsAg) were measured. The association of cccDNA with mutant HBc and histone acetyltransferases (HATs) was assessed by chromatin immunoprecipitation (ChIP). Compared with wild-type HBc, HBc mutants with mutations in clusters III and IV resulted in a significant reduction in HBV RNA levels (all P < 0.05). HBc arginine clusters III and IV mutants also had a significantly lower levels of intracellular HBV DNA (<5% of wild-type; P < 0.001) and HBsAg (<10% of wild-type; P < 0.0001). cccDNA-ChIP assay demonstrated that HBc clusters III and IV mutants had a smaller degree of association with cccDNA (P < 0.001). In the HBc mutants, the association between HATs with cccDNA were reduced. In conclusion, HBc-CTD arginine residues at clusters III and IV play an important role in the regulation of HBV transcription as well as subsequent replication steps, likely through the reduced interaction of HBc with cccDNA and reduced acetylation of cccDNA-bound histones. These findings may provide clues to the identification of novel therapeutic targets against HBV