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This paper applies Information and Communication Technologies (ICT) as well as data analysis to gain a better understanding of the existing perception on the education system. 45,278 tweets were downloaded and processed. Using a lexicon-based approach, examining the most frequently used words, and estimating similarities between terms, we detected that a predominantly negative perception of the education system exists in most of the analysed countries. A positive perception is identified in certain low-income nations. Men exhibit a more positive sentiment than women as well as a higher subjectivity in some countries. The countries that exhibit the most positive perceptions India, Canada, Pakistan, Australia, South Africa and Kenya are also those that manifest the highest subjectivity.
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The morphological analysis of patterns in dried droplets has allowed the generation of efficient techniques for the detection of molecules of medical interest. However, the effectiveness of this method to reveal the coexistence of macromolecules of the same species, but different conformational states, is still unknown. To address this problem, we present an experimental study on pattern formation in dried droplets of bovine serum albumin (BSA), in folded and unfolded conformational states, in saline solution (NaCl). Folded proteins produce a well-defined coffee ring and crystal patterns all over the dry droplet. Depending on the NaCl concentration, the crystals can be small, large, elongated, entangled, or dense. Optical microscopy reveals that the relative concentration of unfolded proteins determines the morphological characteristics of deposits. At a low relative concentration of unfolded proteins (above 2%), small amorphous aggregates emerge in the deposits, while at high concentrations (above 16%), the "eye-like pattern", a large aggregate surrounded by a uniform coating, is produced. The radial intensity profile, the mean pixel intensity, and the entropy make it possible to characterize the patterns in dried droplets. We prove that it is possible to achieve 100% accuracy in identifying 4% of unfolded BSA contained in a protein solution.
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Soroalbumina Bovina , Cloreto de SódioRESUMO
Sustainability is an issue of worldwide concern. Twitter is one of the most popular social networks, which makes it particularly interesting for exploring opinions and characteristics related to issues of social preoccupation. This paper aims to gain a better understanding of the activity related to sustainability that takes place on twitter. In addition to building a mathematical model to identify account typologies (bot and human users), different behavioural patterns were detected using clustering analysis mainly in the mechanisms of posting tweets and retweets). The model took as explanatory variables, certain characteristics of the user's profile and her/his activity. A lexicon-based sentiment analysis in the period from 2006 to 2022 was also carried out in conjunction with a keyword study based on centrality metrics. We found that, in both bot and human users, messages showed mostly a positive sentiment. Bots had a higher percentage of neutral messages than human users. With respect to the used keywords certain commonalities but also slight differences between humans and bots were identified.
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Mídias Sociais , Humanos , Feminino , Comunicação , Software , Rede Social , HábitosRESUMO
Displacements within urban spaces have attracted particular interest among researchers. We examine the journeys that happen in the Madrid Community considering 24 travel typologies and 1390 administrative areas. From an origin-destination (OD) matrix, four classes of major flows are characterised through coarse-graining: hotspot-non-hotspots, non-hotspot-hotspots, hotspots-hotspots, non-hotspot-non-hotspot. In order to make comparisons between them with respect to spatial and temporal patterns, several statistical tests are performed. The spatial activity as well as transition probabilities between administrative zones are also analysed. The mobility network's topology is examined (some parameters such as maximal connected components, average degree, betweenness, and assortativity as well as the k-cores are checked). A model describing the formation of links between zones (existence of at least one trip between them) is constructed based on certain measures of affinity between areas.
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Viagem , ProbabilidadeRESUMO
There is significant global concern about the harmful effects of greenhouse gas and carbon monoxide emissions (deforestation, air pollution, global warming, etc.). The 2015 Paris Agreement on climate change aspires to reduce global warming by achieving a climate-neutral world. Research has been carried out to calculate and diminish the aforementioned emissions in waste, power industry, transport, building, in addition to other areas. The aim of this paper is to analyse the carbon and greenhouse gas emissions across countries around the globe in order to find patterns and correlate them to socio-economic indicators [gross national income (GNI), industrial production (IPI) and human development indexes (HDI)] as well as Twitter interactions regarding climate change. For this purpose, time series and socio-economic data have been downloaded from different repositories including EDGAR (Emissions Database for Global Atmospheric Research), World Bank and UNDP (United Nations Development Programme). Although classical clustering algorithms have already been used in the examination of some environmental issues, we use a non-parametric time series clustering method, which has been suggested in certain scientific literature as a more flexible approach, since any ad hoc parametric assumptions are required. The chosen socio-economic indicators have also demonstrated their relevance in pieces of research related to various fields. With respect to Twitter, which is one of the most popular social networks nowadays, significant analysis has also been performed on the basis of capturing citizens' perceptions on a multitude of matters. We found that several countries such as Brazil, India, China, Nigeria, Russia, United States, Spain, Andorra, Greece, and Qatar show differences in carbon and greenhouse gas emissions patterns. Besides, there does not seem to be a correlation between GNI, IPI and HDI as well as the above mentioned emissions ( correlation < 0.16 ) . Regarding Twitter interactions, a dissimilarity in the distribution of hashtags was detected between the aforementioned countries and the rest of the world. This research can help to identify countries in which more governmental measures are needed to reduce the type of emissions analysed in certain industrial sectors. In addition, it points out the topics related to climate change that seem to generate the most debate on Twitter for countries with an unusual pattern. Supplementary Information: The online version contains supplementary material available at 10.1007/s41742-023-00510-4.
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Steroids from Solanum nudum (SNs) have demonstrated antiplasmodial activity against erythrocytic stages of the Plasmodium falciparum strain FCB-2. It is well known that steroids can alter the membrane function of erythrocytes. Thus, we assessed alterations in the membranes of uninfected red blood cells, the parasite invasiveness and the solute-induced lysis of parasitised red blood cells (pRBCs). induced by SNs. We found that most merozoites were unable to invade SN-treated erythrocytes. However, transmission electron microscopy revealed no effect on the morphology of uninfected erythrocytes treated with either SN2 or diosgenone and neither SN induced haemolysis of uninfected erythrocytes. SN2 and SN4 inhibited isosmotic sorbitol and alanine-induced haemolysis of pRBCs. In contrast, diosgenone and SN1 did not inhibit solute-induced haemolysis. The inhibition of solute-induced lysis of parasitised erythrocytes by SN2 and SN4 suggest an action of these SNs on new permeability pathways of pRBCs.
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Eritrócitos , Extratos Vegetais/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Solanum/química , Esteroides/farmacologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Eritrócitos/efeitos dos fármacos , Eritrócitos/parasitologia , Hemólise/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Extratos Vegetais/química , Plasmodium falciparum/ultraestrutura , Esteroides/química , Esteroides/isolamento & purificaçãoRESUMO
The World Trade Network (WTN) is a network of exchange flows among countries whose topological and statistical properties are a valuable source of information. Degree and strength (weighted degree) are key magnitudes to understand its structure and generative mechanisms. In this work, we describe a stochastic model that yields synthetic networks that closely mimic the properties of annual empirical data. The model combines two popular mechanisms of network generation: preferential attachment and multiplicative process. Agreement between empirical and synthetic networks is checked using the available series from 1962 to 2017.
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High resistance of Plasmodium falciparum malaria to chloroquine poses malaria as a major public health problem in Colombia. In this context, the therapeutic response of uncomplicated P. falciparum malaria patients to chloroquine (CQ), sulfadoxine/pirymethamine (SDXP) and combined therapy (SDXP/CQ) was evaluated according to the WHO/PAHO protocols of 1998. The comparisons were based on a sample of 160 patients with uncomplicated P. falciparum malaria in Turbo and Zaragoza (Antioquia, Colombia). Patients were randomly assigned each of the treatment categories. The results were statistically similar in each municipality. In Turbo percentage of treatment failure was 87.5%, 22.2% and 22.6% for CQ, SDXP and SDXP/CQ, respectively, whereas in Zaragoza, the corresponding treatment failure was 77.7%, 26.5% and 12.1%. During follow up, 50% of subjects with late treatment failure were asymptomatic in Turbo, while 33.3% were asymptomatic in Zaragoza. A high level of treatment failure occurred with CQ monotherapy, while SDXP and SDXP/CQ had acceptable levels of failure, i.e., below 25%. The high percentage of late treatment failure in asymptomatic patients may contribute to increased risk of persistent transmission.
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Antimaláricos/uso terapêutico , Malária Falciparum/tratamento farmacológico , Adulto , Colômbia , Feminino , Humanos , MasculinoRESUMO
Solanum nudum Dunal (Solanaceae) is a plant used in traditional medicine in Colombian Pacific Coast, from which five steroids denominated SNs have been isolated. The SNs compounds have antiplasmodial activity against asexual blood stages of Plasmodium falciparum strain 7G8 with an IC(50) between 20-87microM. However, their mode of action is unknown. Steroids regulate important cellular functions including cell growth, differentiation and death. Thus, the aim of this work was to determine the effects of S. nudum compounds on P. falciparum asexual blood stages and their association with cell death. We found that trophozoite and schizont stages were the most sensitive to SNs. By Giemsa-stained smears, induction of crisis forms was observed. Transmission electron microscopy of treated parasites showed morphological abnormalities such as a cytoplasm rich in vesicles and myelinic figures. The Mitochondria presented no morphological alterations and the nuclei showed no abnormal chromatin condensation. By the use of S. nudum compounds, cell death in P. falciparum was evident by a decrease in mitochondrial membrane potential, DNA fragmentation and cytoplasmic acidification. The asexual blood stages of P. falciparum showed some apoptotic-like and autophagic-like cell death characteristics induced by SNs treatment.
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Eritrócitos/parasitologia , Plasmodium falciparum/efeitos dos fármacos , Solanum/química , Esteroides/farmacologia , Animais , Fragmentação do DNA/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/ultraestrutura , Esteroides/química , Esteroides/isolamento & purificação , Trofozoítos/efeitos dos fármacos , Trofozoítos/crescimento & desenvolvimentoRESUMO
Steroids from Solanum nudum (SNs) have demonstrated antiplasmodial activity against erythrocytic stages of the Plasmodium falciparum strain FCB-2. It is well known that steroids can alter the membrane function of erythrocytes. Thus, we assessed alterations in the membranes of uninfected red blood cells, the parasite invasiveness and the solute-induced lysis of parasitised red blood cells (pRBCs). induced by SNs. We found that most merozoites were unable to invade SN-treated erythrocytes. However, transmission electron microscopy revealed no effect on the morphology of uninfected erythrocytes treated with either SN2 or diosgenone and neither SN induced haemolysis of uninfected erythrocytes. SN2 and SN4 inhibited isosmotic sorbitol and alanine-induced haemolysis of pRBCs. In contrast, diosgenone and SN1 did not inhibit solute-induced haemolysis. The inhibition of solute-induced lysis of parasitised erythrocytes by SN2 and SN4 suggest an action of these SNs on new permeability pathways of pRBCs.
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Eritrócitos , Extratos Vegetais/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Solanum/química , Esteroides/farmacologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/ultraestrutura , Eritrócitos/efeitos dos fármacos , Eritrócitos/parasitologia , Hemólise/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Extratos Vegetais/química , Plasmodium falciparum/ultraestrutura , Esteroides/química , Esteroides/isolamento & purificaçãoRESUMO
Actualmente, existe una necesidad sentida para el desarrollo de nuevos fármacos antimaláricos o de compuestos conocidos dirigidos contra blancos terapéuticos diferentes a los afectados por los medicamentos usuales. Son diversos los blancos que pueden ser aprovechados en Plasmodium, y la alteración de parámetros fisiológicos como el pH y el transporte de solutos pueden explicar la muerte del parásito cuando se usan compuestos antiplasmodiales, lo que representa una opción para el desarrollo de nuevas alternativas antiparasitarias. El propósito de esta revisión es por tanto, proporcionar una visión general de los efectos causados por esteroides, discutiendo el caso específico de los esteroides antiplasmodiales aislados de Solanum nudum y revisar dos procesos fisiológicos importantes en el parásito como posibles blancos terapéuticos, la modificación de permeabilidad del eritrocito infectado y el mantenimiento del pH intracelular de Plasmodium.
In malaria, attention has been posed to search or develop new antimalarial drugs or their modifications against different therapeutic targets in P. falciparum. Therapeutic targets such physiological parameters and solute transport have been proposed to kill the parasite and they represent an option for development of new drugs. We present a review on the effects of steroids, in particular the antiplasmodial steroids isolated from Solanum nudum, stressing two physiological Plasmodium processes such as the new permeability pathways on the infected red blood cells and the cytosolic pH regulation.
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Introducción: Entre los farmacos ampliamente usados en la actualidad para el tratamiento de la malaria por Plasmodium falciparum se encuentra la sulfadoxina-pirimetamina, que es comúnmente administrada en combinación con otros medicamentos. Los eventos adversos informados se han asociado con altas dosis, uso como profilactico o en personas con hipersensibilidad a las sulfas. Objetivo: Evaluar la toxicidad hepßtica y hematica de la sulfadoxina-pirimetamina (SP) administrada en dosis y tiempos terapéuticos para la malaria por P. falciparum no complicada.Metodología: Como parte de un estudio con dise±o experimental, con determinación abierta del efecto, se hizo evaluación hematica y hepatica a 17 personas tratadas con SP. En Turbo (Antioquia, Colombia), los pacientes se captaron consecutivamente y se siguieron por 10 días. Resultados: Las variables hepßticas y hematicas estuvieron alteradas durante el cuadro malarico antes del tratamiento y se normalizaron al poco tiempo del inicio del mismo (1-5 días), que fue eficaz en 100% de los pacientes (medido el día 10). La normalidad de todas las variables en los días 5 y 10 (fase postratamiento) sugiere la ausencia de efectos tóxicos imputables al medicamento. Los efectos adversos fueron pocos y leves y desaparecieron en el control del día 10. Conclusiones: La SP no mostró eventos adversos, toxicidad hepatica ni hemßtica usada en la dosis y el tiempo definidos para el tratamiento de la malaria por P. falciparum sin complicaciones.
Introduction: Sulfadoxine-pyrimethamine is an antimalarial used currently in worldwide for non-complicated falciparum malaria. This drug is administrated in combination with other ones. Previously adverse events had been reported with high doses, used in malaria prophylaxis and patients with hypersensibility to sulfas. Objetive: To evaluate hepatic and haematic toxicity of treatment with sulfadoxine-pyrimethamine (SP) in non-complicated falciparum malaria. Methodology: This was a non-blinded experimental design. In Turbo (Antioquia, Colombia), 17 subjects treated with SP were evaluated for liver and hematic function. All individual were followed for 10 days. Results: Before treatment, liver and hematic function tests were slight altedered. Hematic and liver variables returned to physiological levels after treatment. Treatment had 100% efficacy. All tests were within normal levels throughout the following period (postreatment); this suggests absence of toxic effects associates with treatment. Adverse effects were few and slight, and disappeared on day-10.Conclusions: When is used in time and dose for treatment of non-complicated falciparum malaria, SP neither increased adverse events nor hepatic or hematic toxicity.
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Amodiaquina , Malária , Malária Falciparum , ToxicidadeRESUMO
Introducción: Actualmente existe un número limitado de antimaláricos eficaces, entre ellos amodiaquina; sin embargo, su uso se ha restringido por informes previos de toxicidad hepática y hemática a dosis superiores a 1,500 mg administradas como profiláctico para malaria. No obstante, en dosis terapéuticas antimaláricas los efectos adversos son de intensidad leve o moderada, e incluyen náuseas, vómito y prurito. Objetivo: Evaluar la toxicidad hepática y hemática de la amodiaquina en dosis y tiempo establecidos para tratar la malaria por Plasmodium falciparum no complicada. Metodología: Diseño longitudinal con determinación no ciega del efecto. Se captaron 57 pacientes, seguidos por 10 días (evaluación clínico-parasitológica). Resultados: Antes del tratamiento, las variables hemáticas y hepáticas mostraron alteración leve y se normalizaron postratamiento, que fue 100% eficaz. Los días 5 y 10 del tratamiento todas las variables estaban normales, lo que sugiere ausencia de efectos tóxicos imputables al medicamento. Los efectos adversos fueron pocos, leves y desaparecieron completamente el día 10. Conclusiones: Usada en la dosis (25 mg/kg peso) y el tiempo (3 días) definidos para el tratamiento de la malaria por P. falciparum sin complicaciones, la amodiaquina no mostró efectos adversos ni toxicidad hepática ni hemática.
Background: At present there are few effective antimalarial drugs, amodiaquine is one of them; however, its use has been restricted by previous information about hematic and hepatic toxicity when it is administered as prophylactic at doses greater than 1,500 mg. But at therapeutic doses, the side effects are either slight or of moderate intensity and include nausea, vomit and pruritus. Objective: To evaluate the hepatic and hematic toxicity of amodiaquine administered at doses and time recommended for treatment of uncomplicated Plasmodium falciparum malaria. Methods: Longitudinal design with no blind determination of the effect. A total of 57 patients were included and followed up for 10 days (clinical-parasitological evaluation). Results: Hematic and hepatic variables showed slight alteration previous treatment and were normal postreatment. Therapeutic efficacy of amodiaquine was 100%. All variables were normal at days 5 and 10, suggesting absence of toxic effects imputable to amodiaquine. The side effects were few, slight and disappeared completely at day 10. Conclusions: Amodiaquine administered at doses (25 mg/kg weight) and time (3 days) established for treatment of uncomplicated Plasmodium falciparum malaria is safe, it did not show neither hematic nor hepatic toxicity.
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Amodiaquina , Antimaláricos , Malária , Plasmodium falciparumRESUMO
Objetivo: evaluar la relación entre la presencia y cantidad de leucocitos con hemozoína (pigmento malárico) en sangre periférica y la gravedad malárica.Diseño: estudio descriptivo y transversal.Sujetos: 183 individuos distribuidos en cuatro grupos: 25 individuos sanos, seis pacientes con alteraciones hematológicas y hemólisis, 25 pacientes con enfermedades diferentes a malaria y sin hemólisis y 127 pacientes con malaria por Plasmodium falciparum (64 no complicados y 63 complicados).Mediciones: se realizó recuento de 100 polimorfonucleares neutrófilos (PMN) y 60 mononucleares (MN) en extendidos de sangre periférica usando microscopio de luz, para determinar la presencia de leucocitos con hemozoína.Resultados: el 35 porciento (44/127) de los pacientes maláricos presentaron células con hemozoína y el 25 porciento (32/127) tenían PMN positivos. Se observó una asociación estadísticamente significativa entre malaria complicada y presencia de PMN positivos. En forma similar, se observó una correlación lineal positiva entre la cantidad de PMN positivos y parasitemia (r=0.57; p<0.05 ). No se encontró asociación significativa entre la presencia de MN con hemozoína y complicación malárica. En ninguna de las 56 personas sin malaria se hallaron células con hemozoína.Conclusiones: aunque la frecuencia de pacientes con células positivas para hemozoína en nuestro medio es baja (35 porciento= 44/127), se puede concluir que existe una fuerte asociación entre malaria complicada y la presencia de PMN con hemozoína; por tanto, estos hallazgos sugieren que la presencia de dichas células en extendido de sangre periférica constituyen un signo de alerta y, en consecuencia, en estos casos se debe realizar una evaluación minuciosa del paciente con malaria.
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Humanos , Leucócitos , Malária , Neutrófilos , Plasmodium falciparumRESUMO
La resistencia a medicamentos antimaláricos aumenta la carga de malaria en un país. En Colombia, la situación de los antimaláricos es apremiante dada la alta resistencia de Plasmodium falciparum a la cloroquina y la escasez mundial de amodiaquina. Ante este panorama, se evaluó la respuesta terapéutica a sulfadoxina/pirimetamina (SDXP) y cloroquina (CQ) como monoterapias y en combinación para el tratamiento de malaria no complicada por P. falciparum, aplicando el protocolo de OMS/OPS 1998, en Turbo y Zaragoza, dos municipios de Antioquía, Colombia. Se diseñó una muestra para grupos balanceados y los pacientes fueron asignados aleatoriamente a los grupos de tratamiento. Se evaluaron 160 pacientes con malaria por P. falciparum sin complicaciones. La distribución de pacientes de ambos municipios en cada grupo de tratamiento fue estadísticamente similar en la mayoría de variables. En Turbo hubo un porcentaje de falla terapéutica de 87,5 por ciento a CQ, 22,2 por ciento a SDXP y de 22,6 por ciento a la combinación, mientras en Zaragoza la falla terapéutica fue de 77 por ciento a CQ, 26,5 por ciento a SDXP y 12,1 por ciento a SDXP/CQ. Durante el seguimiento, 50 por ciento y 33,3 por ciento de los pacientes con falla terapéutica tardía en Turbo y Zaragoza, respectivamente, fueron asintomáticos. Este estudio encontró un alto nivel de falla terapéutica con CQ en ambos municipios, mientras la SDXP y la combinación mostraron niveles de falla cercanos al 25 por ciento. Es de anotar el hallazgo de pacientes con falla tardía parasitológica y el riesgo que significa esta situación en la permanencia de la transmisión.