538 research outputs found

    Review of soil salinity assessment for agriculture across multiple scales using proximal and/or remote sensors

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    Mapping and monitoring soil spatial variability is particularly problematic for temporally and spatially dynamic properties such as soil salinity. The tools necessary to address this classic problem only reached maturity within the past 2 decades to enable field- to regional-scale salinity assessment of the root zone, including GPS, GIS, geophysical techniques involving proximal and remote sensors, and a greater understanding of apparent soil electrical conductivity (ECa) and multi- and hyperspectral imagery. The concurrent development and application of these tools have made it possible to map soil salinity across multiple scales, which back in the 1980s was prohibitively expensive and impractical even at field scale. The combination of ECa-directed soil sampling and remote imagery has played a key role in mapping and monitoring soil salinity at large spatial extents with accuracy sufficient for applications ranging from field-scale site-specific management to statewide water allocation management to control salinity within irrigation districts. The objective of this paper is: (i) to present a review of the geophysical and remote imagery techniques used to assess soil salinity variability within the root zone from field to regional scales; (ii) to elucidate gaps in our knowledge and understanding of mapping soil salinity; and (iii) to synthesize existing knowledge to give new insight into the direction soil salinity mapping is heading to benefit policy makers, land resource managers, producers, agriculture consultants, extension specialists, and resource conservation field staff. The review covers the need and justification for mapping and monitoring salinity, basic concepts of soil salinity and its measurement, past geophysical and remote imagery research critical to salinity assessment, current approaches for mapping salinity at different scales, milestones in multi-scale salinity assessment, and future direction of field- to regional-scale salinity assessment

    Contrasting adaptation of xylem to dehydration in two Vitis vinifera L. sub-species

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    Xylem hydraulic properties of agricultural crop species can be linked to their region of origin, but because crop systems are often irrigated to reach optimum quality and yield, key differences in drought resistance are not often considered. We investigated how hydraulic conductivity and xylem vulnerability to drought-induced cavitation of two grapevine cultivars correspond to their centers of domestication with 'Merlot' (Vitis vinifera subspecies occidentalis) having been domesticated in a temperate forest region, and 'Thompson Seedless' (Vitis vinifera subspecies orientalis) domesticated in a semi-arid region. We used anatomical measurements and xylem vulnerability curves to evaluate hydraulic traits and drought resistance. Our results showed that 'Thompson Seedless' was significantly more vulnerable to drought-induced cavitation than 'Merlot'. Bench dehydration produced significantly different estimations of xylem vulnerability to cavitation in each cultivar. This result was consistent with anatomical measurement, with 'Thompson Seedless' stems having greater maximum stem-specific hydraulic conductivity, more vessels, higher vessel density and a greater lumen fraction than 'Merlot'. The relatively large amount of xylem vessels and lumen area in 'Thompson Seedless' is consistent with domestication in a semi-arid habitat where a greater number and size diversity of xylem vessels would be needed to transport water and meet evaporative demand as opposed to cultivars that were domesticated in temperate forest regions like 'Merlot'. These differences appear to expose 'Thompson Seedless' to high xylem vulnerability to cavitation

    Monitoring and Modeling Farmland Productivity Along the Venice Coastland, Italy

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    AbstractThe southern portion of the Venice coastland is a very precarious environment and salt contamination of land and groundwater is a severe problem that is seriously impacting the farmland productivity. Geophysical surveys, lab testing and continuous monitoring of hydrological parameters together with crop yield distribution were performed and acquired from 2010 to 2012 in a 21ha basin cultivated with maize crop and representative of the area. The dataset is here used to set-up a numerical model of soil moisture dynamics coupled with plant transpiration, photosynthesis and growth. The hydraulic model is linked to the atmosphere by the calculation of the stomatal conductance which is optimized for maximum carbon gain. The model is applied to the field site to understand the impact of land elevation, soil heterogeneities, and seawater contamination on land productivity

    Non-invasive vulnerable plaque imaging: how do we know that treatment works?

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    Atherosclerosis is an inflammatory disorder that can evolve into an acute clinical event by plaque development, rupture, and thrombosis. Plaque vulnerability represents the susceptibility of a plaque to rupture and to result in an acute cardiovascular event. Nevertheless, plaque vulnerability is not an established medical diagnosis, but rather an evolving concept that has gained attention to improve risk prediction. The availability of high-resolution imaging modalities has significantly facilitated the possibility of performing in vivo regression studies and documenting serial changes in plaque stability. This review summarizes the currently available non-invasive methods to identify vulnerable plaques and to evaluate the effects of the current cardiovascular treatments on plaque evolution

    The hidden fragility in the heart of the athletes: A review of genetic biomarkers

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    Sudden cardiac death (SCD) is a devastating event which can also affect people in apparent good health, such as young athletes. It is known that intense and continuous exercise along with a genetic background that predisposes a person to the risk of fatal arrhythmias is a trigger for SCD. Therefore, knowledge of the athlete’s genetic conditions underlying the onset of SCD must be extended, in order to develop new effective prevention and/or therapeutic strategies. Arrhythmic features occur across a broad spectrum of cardiac diseases, sometimes presenting with overlapping phenotypes. The genetic basis of arrhythmogenic disorders has been greatly highlighted in the last 30 years, and has shown marked heterogeneity. The advent of next-generation sequencing has constantly updated our understanding of the genetic basis of arrhythmogenic diseases and is laying the foundation for precision medicine. With the exception of a few clinical cases involving a single athlete showing a highly suspected phenotype for the presence of a heart disease, there are few studies to date that analysed the applicability of genetic testing on cohorts of athletes. This evidence shows that genetic testing can contribute to the diagnosis of up to 13% of athletes; however, the presence of clinical markers is essential. This review aims to provide a reference collection on current knowledge of the genetic basis of sudden cardiac death in athletes and to review updated evidence on the effectiveness of genetic testing in early identification of athletes at risk for SCD

    Physical activity and thrombophilic risk in a short series

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    The role of influence on protein C anticoagulant system and PC deficiency-related thrombophilic risk due to strenuous physical exercise is still under discussion. To investigate the modification of the protein C anticoagulant pathway after vigorous exercise, we measured ProC® Global assay, a protein C activity dependent clotting time, in 20 healthy subjects before and immediately after maximal treadmill exercise, and at 5, 15, 30 and 60 min in the recovery phase. The most evident change was a shortening of ProC® Global clotting time from the average basal value of 123 sec to 84 sec at 30 min in post-exercise. Our study shows that the coagulation unbalance observed after strenuous exercise and with no consequence in healthy individuals with normal PC level, could increase the thrombophilic risk in silent carriers of significant defects of the protein C system and occasionally trigger an episode of deep vein thrombosis

    Cerebral embolic lesions detected with diffusion-weighted magnetic resonance imaging following carotid artery stenting: a meta-analysis of 8 studies comparing filter cerebral protection and proximal balloon occlusion.

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    OBJECTIVES: The aim of this meta-analysis was to evaluate and compare the efficacy of the 2 different neuroprotection systems in preventing embolization during carotid artery stenting (CAS), as detected by diffusion-weighted magnetic resonance imaging (DW-MRI). BACKGROUND: Data from randomized and nonrandomized studies comparing both types of embolic protection devices revealed contrasting evidence about their efficacy in neuroprotection, as assessed by the incidence of new ischemic lesions detected by DW-MRI. METHODS: Eight studies, enrolling 357 patients, were included in the meta-analysis. Our study analyzed the incidence of new ischemic lesions/patient, comparing filter cerebral protection and proximal balloon occlusion. RESULTS: Following CAS, the incidence of new ischemic lesions/patient detected by DW-MRI was significantly lower in the proximal balloon occlusion group (effect size [ES]: -0.43; 95% confidence interval [CI]: -0.84 to -0.02, I(2) = 70.08, Q = 23.40). Furthermore, following CAS, the incidence of lesions at the contralateral site was significantly lower in the proximal protection group (ES: -0.50; 95% CI: -0.72 to -0.27, I(2) = 0.00, Q = 3.80). CONCLUSIONS: Our meta-analysis supports the concept that the use of proximal balloon occlusion compared with filter cerebral protection is associated with a reduction of the amount of CAS-related brain embolization. The data should be confirmed by a randomized clinical tria

    CARMA2sh and ULK2 control pathogen-associated molecular patterns recognition in human keratinocytes: psoriasis-linked CARMA2sh mutants escape ULK2 censorship

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    The molecular complexes formed by specific members of the family of CARMA proteins, the CARD domain-containing adapter molecule BCL10 and MALT1 (CBM complex) represent a central hub in regulating activation of the pleiotropic transcription factor NF-κB. Recently, missense mutations in CARMA2sh have been shown to cause psoriasis in a dominant manner and with high penetrancy. Here, we demonstrate that in human keratinocytes CARMA2sh plays an essential role in the signal transduction pathway that connects pathogen-associated molecular patterns recognition to NF-κB activation. We also find that the serine/threonine kinase ULK2 binds to and phosphorylates CARMA2sh, thereby inhibiting its capacity to activate NF-κB by promoting lysosomal degradation of BCL10, which is essential for CARMA2sh-mediated NF-κB signaling. Remarkably, CARMA2sh mutants associated with psoriasis escape ULK2 inhibition. Finally, we show that a peptide blocking CARD-mediated BCL10 interactions reduces the capacity of psoriasis-linked CARMA2sh mutants to activate NF-κB. Our work elucidates a fundamental signaling mechanism operating in human keratinocytes and opens to novel potential tools for the therapeutical treatment of human skin disorders.This publication was made possible by a NPRP award (NPRP 7-1189-3-304) from the Qatar National Research Fund (a member of The Qatar Foundation)

    Long-Term Prognostic Impact of Right Ventricular Dysfunction in Patients with COVID-19

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    The characteristics and clinical course of hospitalized patients with coronavirus disease 2019 (COVID-19) have been widely described, while long-term data are still poor. The aim of this study was to evaluate the long-term clinical outcome and its association with right ventricular (RV) dysfunction in hospitalized patients with COVID-19. This was a prospective multicenter study of consecutive COVID-19 patients hospitalized at seven Italian Hospitals from 28 February to 20 April 2020. The study population was divided into two groups according to echocardiographic evidence of RV dysfunction. The primary study outcome was 1-year mortality. The propensity score matching was performed to balance for potential baseline confounders. The study population consisted of 224 patients (mean age 69 \ub1 14, male sex 62%); RV dysfunction was diagnosed in 63 cases (28%). Patients with RV dysfunction were older (75 vs. 67 years, p < 0.001), had higher prevenance of coronary artery disease (27% vs. 11%, p = 0.003), and lower left ventricular ejection fraction (50% vs. 55%, p <0.001). The rate of 1-year mortality (67% vs. 28%; p 64 0.001) was significantly higher in patients with RV dysfunction compared with patients without. After propensity score matching, patients with RV dysfunction showed a worse long-term survival (62% vs. 29%, p <0.001). The multivariable Cox regression model showed an independent association of RV dysfunction with 1-year mortality. RV dysfunction is a relatively common finding in hospitalized COVID-19 patients, and it is independently associated with an increased risk of 1-year mortality
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