1,321 research outputs found
Thermography to explore plant-environment interactions
Review PaperStomatal regulation is a key determinant of plant photosynthesis and water relations, influencing plant survival, adaptation,
and growth. Stomata sense the surrounding environment and respond rapidly to abiotic and biotic stresses.
Stomatal conductance to water vapour (gs) and/or transpiration (E) are therefore valuable physiological parameters
to be monitored in plant and agricultural sciences. However, leaf gas exchange measurements involve contact with
leaves and often interfere with leaf functioning. Besides, they are time consuming and are limited by the sampling
characteristics (e.g. sample size and/or the high number of samples required). Remote and rapid means to assess
gs or E are thus particularly valuable for physiologists, agronomists, and ecologists. Transpiration influences the leaf
energy balance and, consequently, leaf temperature (Tleaf). As a result, thermal imaging makes it possible to estimate
or quantify gs and E. Thermal imaging has been successfully used in a wide range of conditions and with diverse plant
species. The technique can be applied at different scales (e.g. from single seedlings/leaves through whole trees or
field crops to regions), providing great potential to study plant–environment interactions and specific phenomena
such as abnormal stomatal closure, genotypic variation in stress tolerance, and the impact of different management
strategies on crop water status. Nevertheless, environmental variability (e.g. in light intensity, temperature, relative
humidity, wind speed) affects the accuracy of thermal imaging measurements. This review presents and discusses the
advantages of thermal imaging applications to plant science, agriculture, and ecology, as well as its limitations and
possible approaches to minimize them, by highlighting examples from previous and ongoing researchinfo:eu-repo/semantics/publishedVersio
Comparison of photosynthetic performance of Fagus sylvatica seedlings under natural and artificial shading
peer-reviewedCommitment to sustainable forest management (alternatives to clearfelling) has led to a renewed interest in continuous cover forestry systems, which promote the control of light to produce stand benefits. Physiological performance of shade-tolerant European beech (Fagus sylvatica L.) in response to light availability was investigated in natural regeneration below the canopy in contrast to planted seedlings under artificial-shade conditions. Although beech seedlings had higher photosynthetic capacity with increasing light availability, they were able to maintain positive CO2 assimilation rates under low light levels in both field and controlled conditions. Leaves of seedlings under low light had the ability to use light more efficiently (higher PSII efficiency) than those in high light, which offer some physiological explanation for the ability of beech seedlings to grow under very low light conditions. Whilst caution is advised to interpret results from controlled to field studies, the overall general correspondence in the trend of the physiological response to light levels within beech grown below the canopy and under artificial-shade conditions suggests that it might be possible to extrapolate results from studies performed under artificial shade (nets) to field conditions. Hence, the use of nets may be an alternative way of assessing the potential physiological responses of seedlings to light availability.This research was funded by the COFORD Forest Research Programme under the 2007–2013 National Development Plan, administered by the Irish Department of Agriculture, Food and the Marine (DAFM). Ignacio Sevillano was supported by a Walsh Fellowship from Teagasc (Ireland)
Physiological Responses of Fagus sylvatica and Quercus robur Seedlings to Light Intensity
Conference poster presentationBroadleaf planting has become increasingly important in Ireland over the recent years and light is
recognised as one of the main environmental factors affecting stand development, but to date there has
been little research on broadleaf responses to light intensity, particularly in Ireland. Continuous cover
forestry (CCF) is increasing as an alternative to clear-cutting and uses the control of light to produce
plantation benefits. The physiological responses of beech (Fagus sylvatica) and oak (Quercus robur)
seedlings to four different shade environments (100%, 62%, 51% and 28% of incident
photosynthetically active radiation, PAR) were studied in a shadehouse experiment during the summer
of 2013.
Light-response curves (only measured in the extreme treatments) differed between beech seedlings of
the Control treatment (PAR=100%) and those of the heavy shade treatment (PAR=28%) when PAR >
100 μmol m-2 s-1, while there was little difference for oak between both treatments. Light-response
curves generally showed maximum photosynthetic rates (Amax) at 1500 μmol m-2 s-1 in both treatments,
and this PAR value was used while measuring stomatal conductance (gs) and water use efficiency
(WUE). Significantly higher values of Amax and gs were found in oak than in beech in the 62%, 51% and
28% treatments. There were no significant differences between oak and beech for Amax and gs in the
Control treatment or for WUE in the four treatments.COFORD Forest Research Programm
In vitro analyses of the toxicity, immunological, and gene expression effects of cobalt-chromium alloy wear debris and Co ions derived from metal-on-metal hip implants
Joint replacement has proven to be an extremely successful and cost-effective means of relieving arthritic pain and improving quality of life for recipients. Wear debris-induced osteolysis is, however, a major limitation and causes orthopaedic implant aseptic loosening, and various cell types including macrophages, monocytes, osteoblasts, and osteoclasts, are involved. During the last few years, there has been increasing concern about metal-on-metal (MoM) hip replacements regarding adverse reactions to metal debris associated with the MoM articulation. Even though MoM-bearing technology was initially aimed to extend the durability of hip replacements and to reduce the requirement for revision, they have been reported to release at least three times more cobalt and chromium ions than metal-on-polyethylene (MoP) hip replacements. As a result, the toxicity of metal particles and ions produced by bearing surfaces, both locally in the periprosthetic space and systemically, became a concern. Several investigations have been carried out to understand the mechanisms responsible for the adverse response to metal wear debris. This review aims at summarising in vitro analyses of the toxicity, immunological, and gene expression effects of cobalt ions and wear debris derived from MoM hip implants
Laser-Based Noncontact Blood Pressure Estimation Using Human Body Displacement Waveforms
2022 IEEE/MTT-S International Microwave Symposium - IMS 2022, 19-24 June 2022, Denver, CO, USAMeasurement of the body's displacement at multiple positions allows heart pulse wave propagation to be observed; this is an important step toward noncontact blood pressure measurement. This study investigates the feasibility of performing blood pressure measurements using skin displacement waveforms measured at two positions on a human body. To evaluate the accuracy of the proposed approach, this study uses a pair of laser displacement sensors to enable precise pulse transit time measurement. By comparing the displacement waveforms from the two sensors, the relationship between pulse transit time and blood pressure was evaluated. It is demonstrated experimentally that the blood pressure can be estimated with accuracy of 5.1 mmHg, which is equivalent to the error of an ordinary cuff-type blood pressure monitor
Building professional discourse in emerging markets: Language, context and the challenge of sensemaking
Using ethnographic evidence from the former Soviet republics, this article examines a relatively new and mainly unobserved in the International Business (IB) literature phenomenon of communication disengagement that manifests itself in many emerging markets. We link it to the deficiencies of the local professional business discourse rooted in language limitations reflecting lack of experience with the market economy. This hampers cognitive coherence between foreign and local business entities, adding to the liability of foreignness as certain instances of professional experience fail to find adequate linguistic expression, and complicates cross-cultural adjustments causing multi-national companies (MNCs) financial losses. We contribute to the IB literature by examining cross-border semantic sensemaking through a retrospectively constructed observational study. We argue that a relative inadequacy of the national professional idiom is likely to remain a feature of business environment in post-communist economies for some time and therefore should be factored into business strategies of MNCs. Consequently, we recommend including discursive hazards in the risk evaluation of international projects
Adipocyte-specific protein tyrosine phosphatase 1B deletion increases lipogenesis, adipocyte cell size and is a minor regulator of glucose homeostasis
Peer reviewedPublisher PD
TBC-2 Is Required for Embryonic Yolk Protein Storage and Larval Survival during L1 Diapause in Caenorhabditis elegans
C. elegans first stage (L1) larvae hatched in the absence of food, arrest development and enter an L1 diapause, whereby they can survive starvation for several weeks. The physiological and metabolic requirements for survival during L1 diapause are poorly understood. However, yolk, a cholesterol binding/transport protein, has been suggested to serve as an energy source. Here, we demonstrate that C. elegans TBC-2, a RAB-5 GTPase Activating Protein (GAP) involved in early-to-late endosome transition, is important for yolk protein storage during embryogenesis and for L1 survival during starvation. We found during embryogenesis, that a yolk::green fluorescent protein fusion (YP170::GFP), disappeared much more quickly in tbc-2 mutant embryos as compared with wild-type control embryos. The premature disappearance of YP170::GFP in tbc-2 mutants is likely due to premature degradation in the lysosomes as we found that YP170::GFP showed increased colocalization with Lysotracker Red, a marker for acidic compartments. Furthermore, YP170::GFP disappearance in tbc-2 mutants required RAB-7, a regulator of endosome to lysosome trafficking. Although tbc-2 is not essential in fed animals, we discovered that tbc-2 mutant L1 larvae have strongly reduced survival when hatched in the absence of food. We show that tbc-2 mutant larvae are not defective in maintaining L1 diapause and that mutants defective in yolk uptake, rme-1 and rme-6, also had strongly reduced L1 survival when hatched in the absence of food. Our findings demonstrate that TBC-2 is required for yolk protein storage during embryonic development and provide strong correlative data indicating that yolk constitutes an important energy source for larval survival during L1 diapause
Waterpipe tobacco use in the United Kingdom: A cross-sectional study among university students and stop smoking practitioners
© 2016 Jawad et al.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Introduction: Despite cigarette-like adverse health outcomes associated with waterpipe tobacco smoking and increase in its use among youth, it is a much underexplored research area. We aimed to measure the prevalence and patterns of waterpipe tobacco use and evaluate tobacco control policy with respect to waterpipe tobacco, in several universities across the UK. We also aimed to measure stop smoking practitioners' encounter of waterpipe tobacco smoking. Methods: We distributed an online survey to six UK universities, asking detailed questions on waterpipe tobacco. Multivariable logistic regression models, adjusted for age, gender, ethnicity, graduate status, university and socioeconomic status (SES) assessed associations between waterpipe tobacco smoking (single use and dual use with cigarettes) and sociodemographic variables. SES was ascertained by average weekly self-spend on non-essentials. We also descriptively analysed data from a 2012 survey of stop smoking practitioners to assess the proportion of clients that used waterpipe regularly. Results: f 2217 student responses, 66.0%(95% CI 63.9-68.0%) had tried waterpipe tobacco smoking; 14.3%(95% CI 12.8-15.8%) reported past-30 day use, and 8.7% (95% CI 7.6-9.9%) reported at least monthly users. Past-30 day waterpipe-only use was associated with being younger (AOR 0.95, 95% CI 0.91-0.99), male (AOR 1.44, 95% CI 1.08-1.94), higher SES (AOR 1.16, 95% CI 1.06-1.28) and belonging to non-white ethnicities (vs. white, AOR 2.24, 95% CI 1.66-3.04). Compared to less than monthly users, monthly users were significantly more likely to have urges to smoke waterpipe (28.1% vs. 3.1%,
Recommended from our members
Identification of the global miR-130a targetome reveals a role for TBL1XR1 in hematopoietic stem cell self-renewal and t(8;21) AML
Gene expression profiling and proteome analysis of normal and malignant hematopoietic stem cells (HSCs) point to shared core stemness properties. However, discordance between mRNA and protein signatures highlights an important role for post-transcriptional regulation by microRNAs (miRNAs) in governing this critical nexus. Here, we identify miR-130a as a regulator of HSC self-renewal and differentiation. Enforced expression of miR-130a impairs B lymphoid differentiation and expands long-term HSCs. Integration of protein mass spectrometry and chimeric AGO2 crosslinking and immunoprecipitation (CLIP) identifies TBL1XR1 as a primary miR-130a target, whose loss of function phenocopies miR-130a overexpression. Moreover, we report that miR-130a is highly expressed in t(8;21) acute myeloid leukemia (AML), where it is critical for maintaining the oncogenic molecular program mediated by the AML1-ETO complex. Our study establishes that identification of the comprehensive miRNA targetome within primary cells enables discovery of genes and molecular networks underpinning stemness properties of normal and leukemic cells
- …