A NEURAL NETWORK REGRESSION MODEL FOR ESTIMATING MAXIMUM DAILY AIR TEMPERATURE USING LANDSAT-8 DATA

Abstract. Urban Heat Islands (UHI) phenomenon is a pressing problem for highly industrialized areas with serious risks for public health. Weather stations guarantee long-term accurate observations of weather parameters, such Air Temperature (AT), but lack appropriate spatial coverage. Numerous studies have argued that satellite Land Surface Temperature (LST) is a relevant parameter for estimating AT maps, exploring both linear regression and Machine Learning algorithms. This study proposes a Neural Network (NN) regression model for estimating the maximum AT from Landsat-8 data. The approach has been tested in a variegated morphological region (Puglia, Italy) using a large stack of data acquired from 2018 to 2020. The algorithm uses the median values of LST and Normalized Difference Vegetation Index (NDVI) computed using different buffer radius around the location of each reference weather station (250 m, 1000 m, and 2000 m) to train the NN model with a K-fold cross-validation strategy. The reference dataset was split into three sets using a stratified sampling approach considering the different station categories: rural, High- and Low-density Urban areas respectively. The algorithm was tested with different learning rates (LR) (0.001 and 0.005). The results show that our NN model accuracy improves with the increase of the buffer radius, minimizing the difference in terms of R^2 between training and evaluation data, with an overall accuracy consistently higher than 0.84. Future research could investigate more input variables in the NN model such as morphology or climate variables and test the algorithm on larger areas

PKA and PDE4D3 anchoring to AKAP9 provides distinct regulation of cAMP signals at the centrosome

Previous work has shown that the protein kinase A (PKA)–regulated phosphodiesterase (PDE) 4D3 binds to A kinase–anchoring proteins (AKAPs). One such protein, AKAP9, localizes to the centrosome. In this paper, we investigate whether a PKA–PDE4D3–AKAP9 complex can generate spatial compartmentalization of cyclic adenosine monophosphate (cAMP) signaling at the centrosome. Real-time imaging of fluorescence resonance energy transfer reporters shows that centrosomal PDE4D3 modulated a dynamic microdomain within which cAMP concentration selectively changed over the cell cycle. AKAP9-anchored, centrosomal PKA showed a reduced activation threshold as a consequence of increased autophosphorylation of its regulatory subunit at S114. Finally, disruption of the centrosomal cAMP microdomain by local displacement of PDE4D3 impaired cell cycle progression as a result of accumulation of cells in prophase. Our findings describe a novel mechanism of PKA activity regulation that relies on binding to AKAPs and consequent modulation of the enzyme activation threshold rather than on overall changes in cAMP levels. Further, we provide for the first time direct evidence that control of cell cycle progression relies on unique regulation of centrosomal cAMP/PKA signals

Acidic environments trigger intracellular H+-sensing FAK proteins to re-balance sarcolemmal acid-base transporters and auto-regulate cardiomyocyte pH

AIMS: In cardiomyocytes, acute disturbances to intracellular pH (pHi) are promptly corrected by a system of finely-balanced sarcolemmal acid-base transporters. However, these fluxes become thermodynamically re-balanced in acidic environments, which inadvertently causes their set-point pHi to fall outside the physiological range. It is unclear whether an adaptive mechanism exists to correct this thermodynamic challenge and return pHi to normal. METHODS AND RESULTS: Following left-ventricle cryo-damage, a diffuse pattern of low extracellular pH (pHe) was detected by acid-sensing pHLIP. Despite this, pHi measured in the beating heart (13C NMR) was normal. Myocytes had adapted to their acidic environment by reducing Cl–/HCO3- exchange (CBE)-dependent acid-loading and increasing Na+/H+ exchange (NHE1)-dependent acid-extrusion, as measured by fluorescence (cSNARF1). The outcome of this adaptation on pHi is revealed as a cytoplasmic alkalinisation when cells are superfused at physiological pHe. Conversely, mice given oral bicarbonate to improve systemic buffering had reduced myocardial NHE1 expression, consistent with a needs-dependent expression of pHi-regulatory transporters. The response to sustained acidity could be replicated in vitro using neonatal ventricular myocytes (NRVMs) incubated at low pHe for 48 h. The adaptive increase in NHE1 and decrease in CBE activities was linked to Slc9a1 (NHE1) upregulation and Slc4a2 (AE2) downregulation. This response was triggered by intracellular H+ ions because it persisted in the absence of CO2/HCO3- and became ablated when acidic incubation media had low chloride concentration, a manoeuvre that reduces the extent of pHi decrease. Pharmacological inhibition of FAK-family non-receptor kinases, previously characterised as pH-sensors, ablated pHi autoregulation. In support of a pHi-sensing role, FAK protein Pyk2 (auto)phosphorylation was reduced within minutes of exposure to acidity, ahead of adaptive changes to pHi control. CONCLUSIONS: Cardiomyocytes fine-tune the expression of pHi-regulators so that pHi is at least 7.0. This autoregulatory feedback mechanism defines physiological pHi and protects it during pHe vulnerabilities. TRANSLATIONAL PERSPECTIVE: As a consequence of the inherent thermodynamic coupling between intra- and extracellular pH (pHi/pHe), sustained changes to perfusion, such as those in coronary disease or development, would have deleterious effects on the internal acid-base milieu of myocytes and hence cardiac function, unless offset by a corrective process. Using in-vivo and in-vitro models of acidification, we characterise this adaptive process functionally, and describe how it is engaged to auto-regulate pHi. This additional layer of homeostatic oversight enables the myocardium to operate within its optimal pHi-range, even at times when vascular perfusion is failing to maintain chemical constancy of the interstitial fluid

The dopamine D1 receptor is expressed and induces CREB phosphorylation and MUC5AC expression in human airway epithelium

Background Dopamine receptors comprise two subgroups, Gs protein-coupled “D1-like” receptors (D1, D5) and Gi-coupled “D2-like” receptors (D2, D3, D4). In airways, both dopamine D1 and D2 receptors are expressed on airway smooth muscle and regulate airway smooth muscle force. However, functional expression of the dopamine D1 receptor has never been identified on airway epithelium. Activation of Gs-coupled receptors stimulate adenylyl cyclase leading to cyclic AMP (cAMP) production, which is known to induce mucus overproduction through the cAMP response element binding protein (CREB) in airway epithelial cells. We questioned whether the dopamine D1 receptor is expressed on airway epithelium, and whether it promotes CREB phosphorylation and MUC5AC expression. Methods We evaluated the protein expression of the dopamine D1 receptor on native human airway epithelium and three sources of cultured human airway epithelial cells including primary cultured airway epithelial cells, the bronchial epithelial cell line (16HBE14o-), and the pulmonary mucoepidermoid carcinoma cell line (NCI-H292) using immunohistochemistry and immunoblotting. To characterize the stimulation of cAMP through the dopamine D1 receptor, 16HBE14o- cells and NCI-H292 cells were treated with dopamine or the dopamine D1 receptor agonists (SKF38393 or A68930) before cAMP measurements. The phosphorylation of CREB by A68930 in both 16HBE14o- and NCI-H292 cells was measured by immunoblot. The effect of dopamine or A68930 on the expression of MUC5AC mRNA and protein in NCI-H292 cells was evaluated by real-time PCR and immunofluorescence staining, respectively. Results The dopamine D1 receptor protein was detected in native human airway epithelium and three sources of cultured human airway epithelial cells. Dopamine or the dopamine D1-like receptor agonists stimulated cAMP production in 16HBE14o- cells and NCI-H292 cells, which was reversed by the selective dopamine D1-like receptor antagonists (SCH23390 or SCH39166). A68930 significantly increased phosphorylation of CREB in both 16HBE14o- and NCI-H292 cells, which was attenuated by the inhibitors of PKA (H89) and MEK (U0126). Expression of MUC5AC mRNA and protein were also increased by either dopamine or A68930 in NCI-H292 cells. Conclusions These results suggest that the activation of the dopamine D1 receptor on human airway epithelium could induce mucus overproduction, which could worsen airway obstructive symptoms

HPV16 E7-Dependent Transformation Activates NHE1 through a PKA-RhoA-Iinduced Inhibition of p38alpha

Background: Neoplastic transformation originates from a large number of different genetic alterations. Despite this genetic variability, a common phenotype to transformed cells is cellular alkalinization. We have previously shown in human keratinocytes and a cell line in which transformation can be turned on and followed by the inducible expression of the E7 oncogene of human papillomavirus type 16 (HPV16), that intracellular alkalinization is an early and essential physiological event driven by the up-regulation of the Na/H-+(+) exchanger isoform 1 (NHE1) and is necessary for the development of other transformed phenotypes and the in vivo tumor formation in nude mice.Methodology: Here, we utilize these model systems to elucidate the dynamic sequence of alterations of the upstream signal transduction systems leading to the transformation-dependent activation of NHE1.Principal Findings: We observe that a down-regulation of p38 MAPK activity is a fundamental step in the ability of the oncogene to transform the cell. Further, using pharmacological agents and transient transfections with dominant interfering, constitutively active, phosphorylation negative mutants and siRNA strategy to modify specific upstream signal transduction components that link HPV16 E7 oncogenic signals to up-regulation of the NHE1, we demonstrate that the stimulation of NHE1 activity is driven by an early rise in cellular cAMP resulting in the down-stream inhibition of p38 MAPK via the PKA-dependent phosphorylation of the small G-protein, RhoA, and its subsequent inhibition.Conclusions: All together these data significantly improve our knowledge concerning the basic cellular alterations involved in oncogene-driven neoplastic transformation

Geostructural survey and stability analysis of the calcareous cliff of Vieste (Gargano-Southern Italy)

Some years ago several large collapses of the fractured calcareous rocks in the Vieste cliff occurred. Due to both the structural condition of the rock mass and the tectonic alignment of this part of south east Italy, the bedding is variable. Where the cliff is oriented NE (Iudeca street) the bedding planes are almost dipslope with an inclination lower than the slope angle, whereas in the Punta San Francesco they are counterslope. The intersection of the joints results in the formation of prismatic blocks of various sizes, which are frequently in a condition of incipient fall. A combined geological and structural survey of the cliff was undertaken and distinct element analyses performed to evaluate the evolution of the stress-strain behaviour of the cliff. © Springer-Verlag 2008

An interactive webgis framework for coastal erosion risk management

The Italian coastline stretches over about 8350 km, with 3600 km of beaches, representing a significant resource for the country. Natural processes and anthropic interventions keep threatening its morphology, moulding its shape and triggering soil erosion phenomena. Thus, many scholars have been focusing their work on investigating and monitoring shoreline instability. Outcomes of such activities can be largely widespread and shared with expert and non-expert users through Web mapping. This paper describes the performances of a WebGIS prototype designed to disseminate the results of the Italian project Innovative Strategies for the Monitoring and Analysis of Erosion Risk, known as the STIMARE project. While aiming to include the entire national coastline, three study areas along the regional coasts of Puglia and Emilia Romagna have already been implemented as pilot cases. This WebGIS was generated using Free and Open-Source Software for Geographic information systems (FOSS4G). The platform was designed by combining Apache http server, Geoserver, as open-source server and PostgreSQL (with PostGIS extension) as database. Pure javascript libraries OpenLayers and Cesium were implemented to obtain a hybrid 2D and 3D visualization. A user-friendly interactive interface was programmed to help users visualize and download geospatial data in several formats (pdf, kml and shp), in accordance with the European INSPIRE directives, satisfying both multi-temporal and multi-scale perspectives

Bacteriemia por enterobacterias en adultos en un hospital universitario: análisis de cinco años Bacteremia by enterobacteria in adults from a university hospital: a five year analysis

La bacteriemia sigue siendo una de las causas más importantes de morbilidad y mortalidad en pacientes adultos, a pesar de los numerosos antimicrobianos hoy disponibles y del aumento de las medidas de soporte. El objetivo del presente estudio fue analizar los episodios de bacteriemia por enterobacterias adquiridas en la comunidad y durante la hospitalización registrados durante un período de cinco años, estableciendo la prevalencia de especies, los factores de riesgo y los focos, así como la sensibilidad a los antimicrobianos de los microorganismos involucrados. Entre enero de 2000 y diciembre de 2004 se registraron en el Hospital Nacional de Clínicas de Córdoba 129 episodios de bacteriemias por enterobacterias: 45 correspondientes a pacientes ambulatorios (35%) y 84 a hospitalizados (65%). Los factores de riesgo más frecuentes fueron neoplasia (33,3%) y diabetes (12,4%); y los focos más habituales el urinario (29,5%) y el abdominal (13,9%). La enterobacteria aislada con mayor frecuencia en ambas poblaciones fue E. coli, con una incidencia media del 53,5%, seguida de Klebsiella spp. (21,7%) y Enterobacter spp. (12,4%). Las bacteriemias por Klebsiella spp. fueron más comunes en UTI. Esta especie junto con Enterobacter spp. fueron las bacterias más resistentes a los antimicrobianos ensayados.Bacteremia continues to be one of the main causes of morbidity and mortality in adult patients despite the existence of numerous antimicrobial agents and an increase in support measures. The aim of this study was to analyze the cases of community and hospital-acquired bacteremia, by evaluating the prevalence of species, risk factors, source of infection and antimicrobial susceptibility of the microorganisms involved. From January 2000 to December 2004, 129 cases of bacteremia due to enterobacteria were detected in 45 outpatients (35%) and 84 inpatients (65%). The most common risk factors were neoplasia (33.3%) and diabetes (12.4%); being urinary (29.5%) and abdominal (13.9%) the most frequently found sources of infection. E. coli was the most common enterobacteria isolated in both populations, followed by Klebsiella spp. (21.7%), and Enterobacter spp. (12.4%). Klebsiella spp. bacteremia was most common in ICU patients and, together with Enterobacter spp., constituted the most antibiotic-resistant microorganisms

Multimodal hypoxia imaging in a preclinical glioma model

Introduction: Molecular imaging techniques allow early characterization of tumors and quantification of biological processes in vivo. The aim of our study is to analyze the relationship between tumor growth and tumor hypoxia in an orthotopic glioma murine model by using a multimodal procedure, and to compare the features of the different imaging techniques in revealing hypoxia induction. Materials and methods: Engineered U251 cells were gently provided by Dr. Giovanni Melillo, National Cancer Institute, Frederick (MD). These cells express the luciferase reporter gene under control of a constitutive promoter (U251-LUC) or under control of three copies of a Hypoxic Responsive Element (U251-HRE). Cells has been analyzed by means of three different approaches: 1) In vitro evaluation of transcriptional activation of HIF-1\u3b1 at different times after deferoxamine (DFX) treatment by immunocytochemistry (ICC). 2) In vivo analysis of tumoral progression in orthotopic murine models obtained by stereotaxic injection of 105 glioma cells; animals were monitored weekly with BLI (CCD camera), PET ([18F]FDG,[18F]FAZA,[18F]FLT) and MRI to evaluate tumoral progression and hypoxia activation. 3) Ex vivo analysis by H&E staining and hypoxia markers (HIF-1\u3b1 and CAIX) were performed. Results: In vitro studies showed no differences among the two cell lines as regards to HIF-1\u3b1 activation kinetic with a peak of activation between 3 and 6h and a decrease at 20h. In vivo, U251-HRE model showed a detectable and progressive luciferase activity induction starting at 18 days from injection demonstrating that luminescence expression is dependent on HRE-mediated activation. On the other hand, in U251-LUC model luciferase activity was detectable immediately after injection and remained proportional to tumor growth. Lesions were highly proliferative ( [18F]FLT) but hypo-metabolic ([18F]FDG). In partial agreement with the results of U251-HRE, a hypoxia dependent [18F]FAZA uptake was observed at later times (30 days). MRI provided morphological characterization and diffusion studies showed hypoxic necrotic areas only at later days. Ex vivo H&E staining demonstrates that tumors were characterized by nuclear atypia, brisk mitotic activity, microvascular proliferation and necrosis. HIF-1\u3b1 and CAIX were clearly expressed in hypoxic areas, especially in the inner part of the tumor. Conclusions: This study demonstrates that the U251-HRE orthotopic murine model may be proposed as a predictive and reliable tool to evaluate hypoxia dependent processes of human glioma in preclinical studies by BLI. Differences among the three imaging techniques may be related to methods sensitivity. Further ex vivo post mortem measurements of HIF-1\u3b1 and CAIX at earlier times will be performed. Additional studies will be conducted to understand the clinical meaning of early or delayed hypoxia identification in terms of response to treatment. References: SEMENZA GL. Curr Opin Cell Biol 13(2):167-71, 2001. Review. RAPISARDA A. Cancer Research 62, 4316-4324, 200