82 research outputs found
Remote sensing for the observation of senescence in Conference pear trees
Leaf senescence in trees is the phenological stage during which nutrient resorption happens. In this process, part of the nutrients is transferred to the perennial organs of the plant, contributing to tree vitality and, in pome fruit trees, to flowering intensity the following year. Another share of the nutrients remains inside leaf litter and enters the agroecosystem’s nutrient cycles. The timing and duration of leaf senescence influences the ratio between the two parts of nutrients and thus influences nutrient cycles in the agroecosystem.
Among innovative techniques to investigate these processes, satellite remote sensing has proved a valid tool in natural ecosystems. The same cannot be said about fruit orchards, because of the image quality of the satellites active before Sentinel-2, often deemed insufficient for agricultural studies. The features of Sentinel-2, instead, offer new possibilities for monitoring phenology in agricultural environments.
This research aims to study senescence in Conference pear trees, in three regions of Flanders (Belgium). One cloud-free Sentinel-2 image, acquired in the middle of the senescence period, was analysed, by means of different spectral indices. Ground data was collected through a network of 34 webcams with an RGB camera. A visual analysis was performed, to determine the beginning of senescence (the moment in which the first yellow/red leaves appear in the canopy) and the end of senescence (the moment in which the entire canopy turns yellow/red).
Webcam data showed that leaf (dis)colouration started between September and October, during a one-month time span. Full discolouration of the canopy, occurring at the end of November, was instead more synchronous. Moreover, some trees only turned yellow, while others showed red leaves, probably a stress indicator.
Sentinel-2 data revealed that spectral indices correlate well with the date of the beginning of senescence, thus suggesting that it would possible to map it.
These results already offer evidence that monitoring variability in the dynamics of senescence is possible from satellite remote sensing. Current focus is on the link between canopy colour, as it appears in the webcam imagery, and satellite data
Integrated MicroRNA-mRNA Profiling Identifies Oncostatin M as a Marker of Mesenchymal-Like ER-Negative/HER2-Negative Breast Cancer
MicroRNAs (miRNAs) simultaneously modulate different oncogenic networks, establishing a dynamic system of gene expression and pathway regulation. In this study, we analyzed global miRNA and messenger RNA (mRNA) expression profiles of 17 cell lines representing different molecular breast cancer subtypes. Spearman's rank correlation test was used to evaluate the correlation between miRNA and mRNA expression. Hierarchical clustering and pathway analysis were also performed. Publicly available gene expression profiles (n = 699) and tumor tissues (n = 80) were analyzed to assess the relevance of key miRNA-regulated pathways in human breast cancer. We identified 39 significantly deregulated miRNAs, and the integration between miRNA and mRNA data revealed the importance of immune-related pathways, particularly the Oncostatin M (OSM) signaling, associated with mesenchymal-like breast cancer cells. OSM levels correlated with genes involved in the inflammatory response, epithelial-to-mesenchymal transition (EMT), and epidermal growth factor (EGF) signaling in human estrogen receptor (ER)-negative/human epidermal growth factor receptor 2 (HER2)-negative breast cancer. Our results suggest that the deregulation of specific miRNAs may cooperatively impair immune and EMT pathways. The identification of the OSM inflammatory pathway as an important mediator of EMT in triple-negative breast cancer (TNBC) may provide a novel potential opportunity to improve therapeutic strategies
Irradiancia e irradiación UV-A a partir de medidas con radiómetros a 380 nm para aplicaciones ambientales de la energía solar
El correcto dimensionamiento de plantas de tratamiento por fotocatálisis solar requiere del conocimiento del recurso solar UV (280-400 nm) a nivel de la superficie terrestre. El UV-B (280-315nm), sólo constituye el 10% del total y se transmite sólo el 55% al ingresar al reactor, mientras que el UV-A(315-400 nm) se transmite en un 89%. En este trabajo se presenta y evalúa un método para calcular la irradiancia e irradiación UV-A a partir de mediciones a 380nm por medio del uso de un factor de escala dependiente del ángulo cenital solar. Los errores en la irradiancia calculada van del 18% a θ = 90º hasta 4% a θ =10º. El error en la irradiación UV-A calculada es del 10.2% para las integrales diarias. Estos errores están dentro del rango de incertidumbre aceptable para la mayoría de los sistemas fotocatalíticos solares y pueden ser usadas para los estudios de factibilidad.Proper dimensioning of plants for photocatalytic treatment of wastewaters require the knowledge of the UV solar resource availability. In this work, a method to calculate UV-A irradiance and irradiation from measurements at 380 nm by means of a scale factor dependant only on the solar zenith angle is proposed and evaluated. Errors in the calculated UV-A irradiance range from 18% at θ = 90º to 4% at θ =10º. Errors in the calculated UV-A irradiation are less than 11% for daily integrals. These errors are well within the range of acceptable uncertainty for most photocatalytic systems dimensioning and the procedure may be use for other applications as well. The next step is the establishment of relationships between UV-A and global solar radiation, and a map of the solar UV-A resource for Argentina.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES
Irradiancia e irradiación UV-A a partir de medidas con radiómetros a 380 nm para aplicaciones ambientales de la energía solar
El correcto dimensionamiento de plantas de tratamiento por fotocatálisis solar requiere del conocimiento del recurso solar UV (280-400 nm) a nivel de la superficie terrestre. El UV-B (280-315nm), sólo constituye el 10% del total y se transmite sólo el 55% al ingresar al reactor, mientras que el UV-A(315-400 nm) se transmite en un 89%. En este trabajo se presenta y evalúa un método para calcular la irradiancia e irradiación UV-A a partir de mediciones a 380nm por medio del uso de un factor de escala dependiente del ángulo cenital solar. Los errores en la irradiancia calculada van del 18% a θ = 90º hasta 4% a θ =10º. El error en la irradiación UV-A calculada es del 10.2% para las integrales diarias. Estos errores están dentro del rango de incertidumbre aceptable para la mayoría de los sistemas fotocatalíticos solares y pueden ser usadas para los estudios de factibilidad.Proper dimensioning of plants for photocatalytic treatment of wastewaters require the knowledge of the UV solar resource availability. In this work, a method to calculate UV-A irradiance and irradiation from measurements at 380 nm by means of a scale factor dependant only on the solar zenith angle is proposed and evaluated. Errors in the calculated UV-A irradiance range from 18% at θ = 90º to 4% at θ =10º. Errors in the calculated UV-A irradiation are less than 11% for daily integrals. These errors are well within the range of acceptable uncertainty for most photocatalytic systems dimensioning and the procedure may be use for other applications as well. The next step is the establishment of relationships between UV-A and global solar radiation, and a map of the solar UV-A resource for Argentina.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES
Irradiancia e irradiación UV-A a partir de medidas con radiómetros a 380 nm para aplicaciones ambientales de la energía solar
El correcto dimensionamiento de plantas de tratamiento por fotocatálisis solar requiere del conocimiento del recurso solar UV (280-400 nm) a nivel de la superficie terrestre. El UV-B (280-315nm), sólo constituye el 10% del total y se transmite sólo el 55% al ingresar al reactor, mientras que el UV-A(315-400 nm) se transmite en un 89%. En este trabajo se presenta y evalúa un método para calcular la irradiancia e irradiación UV-A a partir de mediciones a 380nm por medio del uso de un factor de escala dependiente del ángulo cenital solar. Los errores en la irradiancia calculada van del 18% a θ = 90º hasta 4% a θ =10º. El error en la irradiación UV-A calculada es del 10.2% para las integrales diarias. Estos errores están dentro del rango de incertidumbre aceptable para la mayoría de los sistemas fotocatalíticos solares y pueden ser usadas para los estudios de factibilidad.Proper dimensioning of plants for photocatalytic treatment of wastewaters require the knowledge of the UV solar resource availability. In this work, a method to calculate UV-A irradiance and irradiation from measurements at 380 nm by means of a scale factor dependant only on the solar zenith angle is proposed and evaluated. Errors in the calculated UV-A irradiance range from 18% at θ = 90º to 4% at θ =10º. Errors in the calculated UV-A irradiation are less than 11% for daily integrals. These errors are well within the range of acceptable uncertainty for most photocatalytic systems dimensioning and the procedure may be use for other applications as well. The next step is the establishment of relationships between UV-A and global solar radiation, and a map of the solar UV-A resource for Argentina.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES
Cytomegalovirus Infection Is Associated with Development of Chronic Lung Allograft Dysfunction
Background Cytomegalovirus (CMV) is the major and most common opportunistic infection complicating lung transplant (LTX). The aim of this study was to analyse the epidemiological aspects of CMV infection in lung transplant patients subject to a pre-emptive anti-CMV approach and to study the impact of this infection on lung transplant outcome, in terms of onset of chronic lung allograft dysfunction (CLAD).Methods This single-centre retrospective study enrolled 87 LTX patients (median age 55.81 years; 41 females, 23 single LTX, 64 bilateral LTX). All patients were managed with a pre-emptive anti-CMV approach. The incidences of the first episode of CMV infection, 1, 3, 6 and 12 months after LTX, were 12.64%, 44.26%, 50.77% and 56.14%. A median interval of 41 days elapsed between LTX and the first episode of CMV infection. The median blood load of CMV-DNA at diagnosis was 20,385 cp/ml; in 67.64% of cases, it was also the peak value. Patients who had at least one episode had shorter CLAD-free survival. Patients who had three or more episodes of CMV infection had the worst outcome.Results CMV infection was confirmed to be a common event in lung transplant patients, particularly in the first three months after transplant. It had a negative impact on transplant outcome, being a major risk factor for CLAD. The hypothesis that lower viral replication thresholds may increase the risk of CLAD is interesting and deserves further investigation. © 2022, The Author(s)
Characterization of NKG2-A/-C, Kir and CD57 on NK Cells Stimulated with pp65 and IE-1 Antigens in Patients Awaiting Lung Transplant
Introduction: Cytomegalovirus (CMV) is the leading opportunistic infection in lung transplant (LTx) recipients. CMV is associated with graft failure and decreased survival. Recently, new antiviral therapies have been proposed. The present study aimed to investigate NK and T cell subsets of patients awaiting LTx. We analyzed the cellular populations between reactive and non-reactive QuantiFERON (QF) CMV patients for the prediction of immunological response to infection. Methods: Seventeen pre-LTx patients and 15 healthy controls (HC) have been enrolled. QF and IFN-gamma ELISA assay detections were applied. NK cell subsets and T cell and proliferation assay were detected before and after stimulation with pp-65 and IE-1 CMV antigens after stratification as QF+ and QF-. Furthermore, we quantified the serum concentrations of NK- and T-related cytokines by bead-based multiplex analysis. Results: CD56(br)CD16(low)NKG2A(+)KIR(+) resulted in the best discriminatory cellular subsets between pre-LTx and HC. Discrepancies emerged between serology and QF assay. Better proliferative capability emerged from patients who were QF+, in particular in CD8 and CD25-activated cells. CD56(br)CD16(low), adaptive/memory-like NK and CD8Teff were highly increased only in QF+ patients. Conclusions: QF more than serology is useful in the detection of patients able to respond to viral infection. This study provides new insights in terms of immunological responses to CMV in pre-LTX patients, particularly in NK and T cells biology
Markers of Bronchiolitis Obliterans Syndrome after Lung Transplant: Between Old Knowledge and Future Perspective
Bronchiolitis obliterans syndrome (BOS) is the most common form of CLAD and is characterized by airflow limitation and an obstructive spirometric pattern without high-resolution computed tomography (HRCT) evidence of parenchymal opacities. Computed tomography and microCT analysis show abundant small airway obstruction, starting from the fifth generation of airway branching and affecting up to 40–70% of airways. The pathogenesis of BOS remains unclear. It is a multifactorial syndrome that leads to pathological tissue changes and clinical manifestations. Because BOS is associated with the worst long-term survival in LTx patients, many studies are focused on the early identification of BOS. Markers may be useful for diagnosis and for understanding the molecular and immunological mechanisms involved in the onset of BOS. Diagnostic and predictive markers of BOS have also been investigated in various biological materials, such as blood, BAL, lung tissue and extracellular vesicles. The aim of this review was to evaluate the scientific literature on markers of BOS after lung transplant. We performed a systematic review to find all available data on potential prognostic and diagnostic markers of BOS
Headache prevalence in the population of L’Aquila (Italy) after the 2009 earthquake
Stress induced by the events of daily life is considered a major factor in pathogenesis of primary tension-type headache. Little is known about the impact that could have a more stressful event, like a natural disaster, both in patients with chronic headache, both in people that do not had headache previously. The aim of the present study was to observe the prevalence of headache in the population following the devastating earthquake that affected the province of L’Aquila on April 6, 2009. The study population was conducted in four tent cities (Onna, Bazzano, Tempera-St. Biagio, Paganica). Sanitary access is recorded in the registers of medical triage, in the first 5 weeks, after the April 6, 2009. The prevalence of primary headache presentation was 5.53% (95% CI 4.2–7.1), secondary headache was 2.82% (95% CI 1.9–4.9). Pain intensity, assessed by Numerical Rating Scale score showed a mean value of 7 ± 1.1 (range 4–10). The drugs most used were the NSAIDs (46%) and paracetamol (36%), for impossibility of finding causal drugs. This study shows how more stressful events not only have an important role in determining acute exacerbation of chronic headache, but probably also play a pathogenic role in the emergence of primary headache. Also underlines the lack of diagnostic guidelines or operating protocols to early identify and treat headache in the emergency settings
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