103 research outputs found
Mining M-Grams by a Granular Computing Approach for Text Classification
No full textText mining and text classification are gaining more and more importance in AI related research fields. Researchers are particularly focused on classification systems, based on structured data (such as sequences or graphs), facing the challenge of synthesizing interpretable models, exploiting gray-box approaches. In this paper, a novel gray-box text classifier is presented. Documents to be classified are split into their constituent words, or tokens. Groups of frequent m tokens (or m-grams) are suitably mined adopting the Granular Computing framework. By fastText algorithm, each token is encoded in a real-valued vector and a custom-based dissimilarity measure, grounded on the Edit family, is designed specifically to deal with m-grams. Through a clustering procedure the most representative m-grams, pertaining the corpus of documents, are extrapolated and arranged into a Symbolic Histogram representation. The latter allows embedding documents in a well-suited real-valued space in which a standard classifier, such as SVM, can safety operate. Along with the classification procedure, an Evolutionary Algorithm is in charge of performing features selection, which is able to select most relevant symbols – m-grams – for each class. This study shows how symbols can be fruitfully interpreted, allowing an interesting knowledge discovery procedure, in lights with the new requirements of modern explainable AI systems. The effectiveness of the proposed algorithm has been proved through a set of experiments on paper abstracts classification and SMS spam detection
An Information Granulation Approach Through m-Grams for Text Classification
No full textNowadays, researchers and practitioners are focusing not only on high-performance systems in terms of classification capabilities, but also in generating gray-box interpretable models in which the relations belonging to the input-output mapping is also explainable, in line with the“explainable AI" paradigm. In this paper is proposed a text mining system capable of classifying text excerpts belonging to a suitable corpus through the human-centric Granular Computing approach. The system is grounded on two granulation levels of text, i.e. the set of extracted m-grams and a suitable hard partition of the latter obtained through both a well-suited dissimilarity measure between m-grams along with a clustering algorithm. The procedure allows embedding a text document – exploiting the Symbolic Histogram technique – in a real-valued vector space where standard Machine Learning algorithms, such as SVM, can safely operate. An evolutionary metaheuristic based on a Genetic Algorithm is, then, in charge of optimizing the system metaparameters, as well as performing a wrapper-like feature selection. This procedure allows carrying out knowledge discovery on the obtained models selecting relevant and interpretable information granules (i.e. m-grams) related to the classification task. The current study presents a new evaluation framework of the performance of the entire system in terms of generalization capabilities and the obtained results show the reliability of the overall procedure. Furthermore, a new conceptual framework is also presented in term of the “representation" problem in automated Pattern Recognition systems
Crystal structure of the kringle domain of human receptor tyrosine kinase-like orphan receptor 1 (hROR1)
No full textReceptor tyrosine kinase-like orphan receptors (RORs) are monotopic membrane proteins belonging to the receptor tyrosine kinase (RTK) family. RTKs play a role in the control of most basic cellular processes, including cell proliferation, differentiation, migration and metabolism. New emerging roles for RORs in cancer progression have recently been proposed: RORs have been shown to be overexpressed in various malignancies but not in normal tissues, and moreover an abnormal expression level of RORs on the cellular surface is correlated with high levels of cytotoxicity in primary cancer cells. Monoclonal antibodies against the extracellular part of RTKs might be of importance to prevent tumor cell growth: targeting extracellular kringle domain molecules induces the internalization of RORs and decreases cell toxicity. Here, the recombinant production and crystallization of the isolated KRD of ROR1 and its high-resolution X-ray crystal structure in a P3121 crystal form at 1.4 Å resolution are reported. The crystal structure is compared with previously solved three-dimensional structures of kringle domains of human ROR1 and ROR2, their complexes with antibody fragments and structures of other kringle domains from homologous proteins
Bioactive natural products from the mediterranean sponge Raspaciona aculeata (Johnston, 1842)
No full textAssessing the effects of neonicotinoid insecticide on the bivalve mollusc Mytilus galloprovincialis
Get PDFIn the present work, the marine invertebrate Mytilus galloprovincialis was used as model organism to evaluate the toxic effects of the neonicotinoid Calypso 480 SC (CAL) following 20 days of exposure to sub-lethal concentrations of 7.77 mg L1 (0.1% 96 h-LC50) and 77.70 mg L1 (1% 96 h-LC50), and a recovery period of 10 days in uncontaminated seawater. Results revealed that exposure to both concentrations of CAL increased significantly mortality rate in the cells of haemolymph and digestive gland, while digestive gland cells were no longer able to regulate cell volume. Exposure significantly reduced haemolymph parameters (Cl, Na+), affected the enzymatic activities of superoxide dismutase of digestive gland and catalase of gill, and caused also histopathological alterations in digestive gland and gills. Main histological damages detected in mussels were lipofuscin accumulation, focal points of necrosis, mucous overproduction and infiltrative inflammations. Interestingly, alterations persisted after the recovery period in CALfree water, especially for haemocyte parameters (K+, Na+, Ca2+, lactate dehydrogenase, glucose). A slight recovery of histological conditions was detected. These findings suggested that sub-chronic exposure to the neonicotinoid insecticide caused significant alterations in both cell and tissue parameters of M. galloprovincialis. Considering the ecologically and commercially important role of mussels in coastal waters, a potential risk posed by neonicotinoids to this essential aquatic resource can be highlighted
Expression of Langerin/CD 207 and α-smooth muscle actin in ex vivo rabbit corneal keratitis model
No full textThe constant exposure of ocular surface to external environment and then to several microbial agents is often related to the pathogenesis of various inflammatory eye disorders. In the present study α-Smooth Muscle Actin (α-SMA) and Langerin CD/207 expression and function was investigated in a rabbit corneal keratitis. The inflammation was induced by the secreted form of glycoprotein B (gB1s) of HSV-1, in an ex vivo rabbit corneal model. α-SMA is often used as a marker for myofibroblasts. In this study, for the first time, we show α-SMA positive corneal epithelial cells, during HSV-1 cornea inflammation, demonstrating a crucial role in wound healing, especially during remodeling phase. Furthermore, we show the presence of Dendritic Cells Langerin CD/207 positive, located mainly in the basal epithelial layer and in corneal stroma during the inflammatory processes. Our result validating the ex vivo organotypic rabbit corneal model, for the study about pathogenesis of HSV-1 ocular infection
Antimicrobial efficacy assessment and rheological investigation of two different hand sanitizers compared with the standard reference WHO formulation 1
Get PDF(1) Background: recently, the use of alcohol-based hand sanitizers (ABHSs) has become very frequent, and an evaluation of the stability and effectiveness of their formulations is a critical topic which should be carefully considered. (2) Methods: starting from the characterization of the hand sanitizers object of the study, our interest was focused on their rheological behavior in order to confirm their intrinsic features, but also the stability of each formulation in different conditions of shear and temperature; the second aspect concerns the antimicrobial assessment through a panel of in vitro and in vivo experimental trials. (3) Results: rheological investigation confirmed good stability for the two hand sanitizers in gel formula with respect to the reference in liquid formula; the antimicrobial activity evaluation showed good efficacy of each formulation both in vitro and in vivo. (4) Conclusions: altogether, our overview presents a valid quality control assessment to ensure the stability and efficacy of an alcohol-based hand sanitizer
Acute effects of neonicotinoid insecticides on Mytilus galloprovincialis: A case study with the active compound thiacloprid and the commercial formulation calypso 480 SC
Get PDFPesticides can enter aquatic environments potentially affecting non-target organisms. Unfortunately, the effects of such substances are still poorly understood. This study investigated the effects of the active neonicotinoid substance thiacloprid (TH) and the commercial product Calypso 480 SC (CA) (active compound 40.4% TH) on Mytilus galloprovincialis after short-term exposure to sublethal concentrations. Mussels were tested for seven days to 0, 1, 5 and 10 mg L−1 TH and 0, 10, 50 and 100 mg L−1 CA. For this purpose, several parameters, such as cell viability of haemocytes and digestive cells, biochemical haemolymph features, superoxide dismutase (SOD) and catalase (CAT) enzymatic activity of gills and digestive gland, as well as histology of such tissues were analysed. The sublethal concentrations of both substances lead to abatement or completely stopping the byssal fibres creation. Biochemical analysis of haemolymph showed significant changes (P < 0.01) in electrolytes ions (Cl−, K+, Na+, Ca2+, S-phosphor), lactate dehydrogenase (LDH) enzyme activity and glucose concentration following exposure to both substances. The TH-exposed mussels showed significant imbalance (P < 0.05) in CAT activity in digestive gland and gills. CA caused significant decrease (P < 0.05) in SOD activity in gills and in CAT activity in both tissues. Results of histological analyses showed severe damage in both digestive gland and gills in a time- and concentration-dependent manner. This study provides useful information about the acute toxicity of a neonicotinoid compound and a commercial insecticide on mussels. Nevertheless, considering that neonicotinoids are still widely used and that mussels are very important species for marine environment and human consumption, further researches are needed to better comprehend the potential risk posed by such compounds to aquatic non-target species
Caracterización del financiamiento de las micro y pequeñas empresas del sector comercio del Perú: caso Confecciones “M&M” - Pomabamba, 2018
No full textEl presente trabajo de investigación tuvo por objetivo describir las características del financiamiento de las micro y pequeñas empresas del sector comercio del Perú y de Confecciones “M&M” – Pomabamba, 2018. La investigación fue tipo cualitativa- descriptiva. Respecto al objetivo Específico 1: Los autores mencionan que las Mype tienen muchas dificultades para poder acceder fácilmente a un crédito para el desarrollo de la empresa, ya sea por las tasas de interés, las garantías, historial crediticio, activos muy insignificantes, entre otros. Los mismos que coinciden con los antecedentes internacionales Logreira y Bonnet (2012), Gonzales (2014) quienes diagnosticaron que, de las alternativas de crédito existentes, las microempresas entienden muy pocas de orígenes de préstamos y se restringen a utilizar las más comunes, como lo son sus deudas acumulados y préstamos con bancos comerciales. Respecto al objetivo específico 2: Confecciones M&M – Pomabamba, obtuvimos que la empresa si recurre al financiamiento externo siendo la Caja Municipal de Ahorro y Crédito para poder financiar sus actividades principales de la empresa y que esto es primordial para que las micro y pequeñas empresas se desarrollen, el financiamiento fue en soles, el monto solicitado fue brindado sin limitaciones por un monto de S/ 25,000 a una tasa de interés de 6% mensual por un plazo de 24 meses (largo plazo). El uso que le dieron al crédito obtenido fue para capital de trabajo. Respecto al Objetivo específico 3: Según los resultados encontrados en el objetivo específico N° 1 y en el caso de investigación (objetivo específico N° 2) referente a las fuentes de financiamiento de las Mype No Coinciden, pues la Confecciones M&M recurre al financiamiento de terceros de entidades financieras no bancarias a una tasa de interés alta mientras que las Mypes estudiadas a las entidades bancarias con tasa de interés bajo para poder desarrollar sus actividades, la coincidencia la encontramos en las facilidades que han tenido en ambos casos para la obtención de financiamiento. Se concluye que el financiamiento en las MYPE es de suma importancia para su crecimiento en el mercado, y para Confecciones M&M ayudó en el incremento de sus ventas, de la misma manera sus ganancias.Tesi
Expression of Langerin/CD207 in airways, lung and associated lymph nodes of a stranded striped dolphin (Stenella coeruleoalba)
No full textThe airways and lungs of vertebrates are an entrance way for several microbial pathogens. Cetaceans present an upper and lower respiratory anatomy that allows the rapid flow of large air volumes, which may lead to high susceptibility to respiratory infections. Mortality and stranding rate of Cetaceans increased dramatically, so wide the knowledge about the immune system and specific antibodies identifying immune cells populations, is of fundamental importance to monitor and document cetacean health. The aim of this study was to identify the localization of dendritic cells marked by Langerin/CD207 in airways, lungs and associated lymph nodes, of the striped dolphin Stenella coeruleoalba. Samples of trachea, bronchi, lungs and lung-associated lymph nodes were obtained from a stranded adult male of Stenella coeruleoalba. Our results showed abundant lymphoid aggregates (LAs) in the lung of S. ceruleoalba. Langerhans-like dendritic cells were well distributed along the epithelium and interstitium of respiratory tract and in associated lymph nodes. The present study deepens the knowledge about the cetacean's immune system and report about the exploitability of a commercial antibody (Langerin/CD207) for cetacean species
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