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Diverse methodologies exist to determine the chemical composition, proximate analysis, and calorific value of biomass. Researchers select and apply a specific methodology according to the lignocellulosic material they study and the budgetary resources available. In this project, we determined the primary chemical constitution and proximate analysis of Prosopis laevigata (Humb. & Bonpl.) Jonhst wood using a traditional chemical method and a novel procedure based on the deconvolution of the DTG signal produced by TGA. The highest calorific value was verified using a calorimetric pump based on mathematical models. We also conducted elemental analysis and a microanalysis of ash, and applied Fourier transform infrared spectroscopic analysis (FT-IR). The means of the results obtained by the chemical method and TGA-DTG, respectively, were: hemicelluloses 7.36%-(8.72%), cellulose 48.28%-(46.08%), lignin 30.57%-(32.44%), extractables 13.53%-(12.72%), moisture 2.03%-(4.96%), ash 1.77%-(1.90%), volatile matter 75.16%-(74.14%), and fixed carbon 23.05%-(18.93%). The procedure with the calorimetric pump generated a calorific value above 20.16 MJ/kg. The range generated by the various models was 18.23-21.07 MJ/kg. The results of the elemental analysis were: carbon 46.4%, hydrogen 6.79%, oxygen 46.43%, nitrogen 0.3%, and sulfur 0.5%. The microanalysis of ash identified 18 elements. The most abundant ones were potassium ˃ calcium ˃ sodium. Based on the infrared spectrum (FT-IR) of Prosopis laevigata wood, we detected the following functional groups: OH, C-H, C=O, CH2, CH3, C-O-C, C-OH, and C4-OH. Our conclusion is that the TGA-DTG method made it possible to obtain results in less time with no need for the numerous reagents that chemical procedures require. The calorific value of P. laevigata wood is higher than the standards. Finally, according to our results, proximate analysis provides the best model for calculating calorific value.

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The production of sugarcane bioethanol generates large volumes of vinasse, an effluent whose final disposal can produce an environmental impact that is of concern. The long-term disposal of vinasse in sugarcane fields could challenge crop management, such as the performance of traditional herbicides, by changing soil properties. This study aimed to evaluate the effect of long-term vinasse application on the field and the dissipation of atrazine and ametryn herbicides in a subtropical sugarcane agroecosystem, and to discuss the potential processes involved in it. Vinasse affected soil properties by increasing pH (12%), electrical conductivity (160%), and soil organic carbon (25%) at 0-10 cm depth of soil. Differences in the herbicide calculated sorption coefficient (Kd) varied according to the pedotransfer function applied and the herbicide type (atrazine or ametryn). During the first seven days after herbicide application, the soil underwent long-term vinasse application and increased atrazine and ametryn dissipation 45% and 33%, respectively, compared with the conventional fertilization scheme (control). The Pesticide Root Zone Model revealed that dissipation was mediated mainly by the degradation process rather than transport or other processes. The long-term application of vinasse in a typical sugarcane field of Tucumán, Argentina decreased the potential groundwater pollution of triazines and, adversely, reduced their bioavailability for weed control. For this, the present study presents original information about how long-term treatment with vinasse may require an adaptation of conventional management practices such as the application of herbicides in Argentina and other sugarcane-producing regions. Integr Environ Assess Manag 2023;00:1-12. © 2023 SETAC.

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Background and study aims As life expectancy increases worldwide, so does the prevalence of biliary tract and pancreatic disorders, resulting in rising demand for invasive procedures such as endoscopic retrograde cholangiopancreatography (ERCP) in the elderly. Few studies have assessed the safety of ERCP in patients 90 years and older, particularly among the Hispanic population. The primary aim of this study was to determine the technical success and adverse events (AEs) associated with ERCP in patients 90 years of age or older in comparison to a younger cohort of patients. Patients and methods A retrospective analysis of all ERCPs done at our institution from 2012 to 2018 was performed. Three hundred ERCPs in patients < 90 years old and all 28 ERCPs done in patients ≥ 90 years old were included in the analysis. Results ERCPs were successfully completed in 96.4% of patients > 90 years old and 96.3% of the < 90-year-old cohort (realtive risk [RR] 1.00, confidence interval 0.92-1.07). There was no difference in the rate of periprocedural AEs. Post-ERCP AEs occurred in 7.1% and 3.0% in patients aged < 90 and > 90 years, respectively (RR 2.38, 0.54-10.48). No deaths were directly attributed to the procedure; however, inpatient mortality was higher in the group aged > 90 years. Conclusions ERCP is safe and effective in nonagenarian patients, and advanced age should not be considered an independent risk factor for AEs nor a contraindication for the procedure.

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Introducción: El eucalipto fue utilizado el 2020 para tratar síntomas del coronavirus, en un intento de comprender el comportamiento reactivo del componente principal el eucaliptol, y con la finalidad de disponer de información preliminar para estudios posteriores, es que se escogió a esta molécula en el presente estudio. Se realizó un estudio químico teórico computacional, se calcularon propiedades moleculares, valores de longitudes de enlace y ángulos, así como propiedades químicas y descriptores químicos de interés en estudios QSAR, de energías y de reactividad. Objetivo: Determinar las propiedades moleculares, y descriptores de reactividad del eucaliptol con el fin de comprender el comportamiento reactivo mediante la Teoría Funcional de la Densidad (DFT). Método: Este estudio computacional utilizo los métodos Hartree Fock y la Teoría Funcional de densidad DFT, las propiedades químicas y descriptores moleculares para el eucaliptol, simulado en condiciones de vacío y en medio etanólico, fueron comparadas con los datos de referencia del Banco de Datos Europeo. Los descriptores ADME se calcularon con la estructura optimizada, usando los servidores en línea SwissADME y ADMETlab. Resultados: En cuanto se refiere a las longitudes de enlace intramolecular se encontró que no hay diferencia estadística significativa entre las longitudes de enlace en los cuatro tratamientos cuánticos. En los orbitales frontera, un band gap de 8,1 eV entre los orbitales HOMO LUMO muestra que la molécula es muy estable, los orbitales HOMO-1 y LUMO+1 de 9,8eV indica que se necesitaría mucha energía para que ocurra una transición electrónica. Conclusión: La teoría DFT B3LYP/6-31G fue aplicada sobre la estructura del eucaliptol, se investigaron algunas propiedades geométricas, electrónicas, de reactividad química y descriptores ADME intentando comprender el comportamiento reactivo de esta molécula, la energía de los orbitales HOMO-LUMO mostraron que la molécula tiene estabilidad energética, y los descriptores ADME sugieren una buena absorción a través de las membranas, finalmente el eucaliptol no es mutagénico desde el punto de vista de la química teórica.

Introduction: Eucalyptol was used in 2020 to treat coronavirus symptoms, in an attempt to understand the reactive behavior of the eucalyptol, a main molecule, and in order to have preliminary information for subsequent studies, this molecule was chosen in this study. A computational theoretical chemical study was carried out, molecular properties, values ​​of bond lengths and angles, as well as chemical properties and chemical descriptors of interest in QSAR, energy and reactivity studies were calculated. Objective: To determine the molecular properties and reactivity descriptors of eucalyptol in order to understand the reactive behavior through the Density Functional Theory (DFT). Method: This computational study used the Hartree Fock methods and the DFT Density Functional Theory, the chemical properties and molecular descriptors for eucalyptol, simulated under vacuum conditions and in ethanolic medium, were compared with the reference data from the Data Bank. European. The ADME descriptors were calculated with the optimized structure, using the online servers SwissADME and ADMETlab. Results: Regarding the intramolecular bond lengths, it was found that there is no statistically significant difference between the bond lengths in the four quantum treatments. In the frontier orbitals, a band gap of 8.1 eV between the HOMO LUMO orbitals shows that the molecule is very stable, the HOMO-1 and LUMO+1 orbitals of 9.8eV indicate that a lot of energy would be needed for a transition to occur. electronics. Conclusion: The DFT B3LYP/6-31G theory was applied to the structure of eucalyptol, some geometric, electronic, chemical reactivity properties and ADME descriptors were investigated trying to understand the reactive behavior of this molecule, the energy of the HOMO-LUMO orbitals showed that the molecule has energetic stability, and the ADME descriptors suggest a good absorption through the membranes, finally eucalyptol is not mutagenic from the point of view of theoretical chemistry.

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Vagus nerve innervates several organs including the heart, stomach, and pancreas among others. Somas of sensory neurons that project through the vagal nerve are located in the nodose ganglion. The presence of purinergic receptors has been reported in neurons and satellite glial cells in several sensory ganglia. In the nodose ganglion, calcium depletion-induced increases in neuron activity can be partly reversed by P2X7 blockers applied directly into the ganglion. The later suggest a possible role of P2X7 receptors in the modulation of neuronal activity within this sensory ganglion. We aimed to characterize the response to P2X7 activation in nodose ganglion neurons under physiological conditions. Using an ex vivo preparation for electrophysiological recordings of the neural discharges of nodose ganglion neurons, we found that treatments with ATP induce transient neuronal activity increases. Also, we found a concentration-dependent increase in neural activity in response to Bz-ATP (ED50 = 0.62 mM, a selective P2X7 receptor agonist), with a clear desensitization pattern when applied every ~ 30 s. Electrophysiological recordings from isolated nodose ganglion neurons reveal no differences in the responses to Bz-ATP and ATP. Finally, we showed that the P2X7 receptor was expressed in the rat nodose ganglion, both in neurons and satellite glial cells. Additionally, a P2X7 receptor negative allosteric modulator decreased the duration of Bz-ATP-induced maximal responses without affecting their amplitude. Our results show the presence of functional P2X7 receptors under physiological conditions within the nodose ganglion of the rat, and suggest that ATP modulation of nodose ganglion activity may be in part mediated by the activation of P2X7 receptors.

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RESUMEN El cumplimiento de las metas de los Objetivos de Desarrollo Sostenible y el fortalecimiento de las competencias para ser ciudadanos globales plantea grandes desafios a las naciones y especialmente, a sus sistemas educativos. En este contexto, se propone el diseno de un modelo de coordenadas curriculares dirigido a la formación de competencias para el desarrollo sostenible y la ciudadanía mundial, dentro de la Institución Universitaria Pascual Bravo (Colombia). Desde un enfoque Qualitativo, con alcance descriptivo y el diseno de teoria fundamentada, se realizó una caracterización que devela la necesidad de avanzar en modelos curriculares de educación superior, cuya base sean los conocimientos teóricos y prácticos a fin de promover el desarrollo y los estilos de vida sostenible. A partir de ahi, se plantea modelo de gestión curricular que permita reflexionar sobre la importancia de articular dichas competencias a los propósitos misionales. Se concluye que, con su aplicación, la comunidad académica puede adoptar la herramienta teórica y establecer un diseno que favorezca la actualización curricular con enfoque hacia el desarrollo sostenible.

ABSTRACT The fulfillment ofthe targets of the Sustainable Development Goals and the strengthening of the competencies to be global citizens brings out great challenges to the nations and, especially to their educational systems. In this context, the design of a model of curricular coordinates aimed at the formation of skills for sustainable development and world citizenship, within la Institución Universitaria Pascual Bravo (Pascual Bravo University Institution for its English conversion) (Colombia), is proposed. From a qualitative approach, with a descriptive scope and grounded theory design, a characterization was carried out that reveals the need to advance in higher education curricular models, whose base is theoretical and practical knowledge in order to promote the development and sustainable life styles. From there, a curricular management model is proposed that allows to reflect on the importance of articulating these competencies to the missionary purposes. It is concluded that, with its application, the academic community can adopt the theoretical tool and establish a design that favors curricular updating with a focus on sustainable development.

RESUMO O cumprimento das metas dos Objetivos de Desenvolvimento Sustentável e o reforço das competéncias para a cidadania global representam grandes desafios para as nações e, especialmente, para os seus sistemas educativos. Neste contexto, propomos a conceção de um modelo de coordenadas curriculares visando a formação de competéncias para o desenvolvimento sustentável e a cidadania global, no âmbito da Instituição Universitária Pascual Bravo (Colômbia). A partir de uma abordagem qualitativa, com um âmbito descritivo e uma conceção teórica fundamentada, foi realizada uma caracterização que revela a necessidade de avançar nos modelos curriculares do ensino superior cuja base o conhecimento teórico e prático, a fim de promover o desenvolvimento sustentável e os estilos de vida. Nesta base, é proposto um modelo de gestão curricular que permite refletir sobre a importância de articular estas competéncias com os objetivos da missão da instituição. Conclui-se que, com a sua aplicação, a comunidade académica pode adotar a ferramenta teórica e estabelecer um desenho que favoreça a atualização do currículo com enfoque no desenvolvimento sustentável.

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Prolonged changes in neural activity trigger homeostatic synaptic plasticity (HSP) allowing neuronal networks to operate within functional ranges. Cell-wide or input-specific adaptations can be induced by pharmacological or genetic manipulations of activity, and by sensory deprivation. Reactive functional changes caused by deafferentation may partially share mechanisms with HSP. Acute hippocampal slices are a suitable model to investigate relatively rapid (hours) modifications occurring after denervation and explore the underlying mechanisms. As during slicing many afferents are cut, we conducted whole-cell recordings of miniature excitatory postsynaptic currents (mEPSCs) in CA1 pyramidal neurons to evaluate changes over the following 12 h. As Schaffer collaterals constitute a major glutamatergic input to these neurons, we also dissected CA3. We observed an average increment in mEPSCs amplitude and a decrease in decay time, suggesting synaptic AMPA receptor upregulation and subunit content modifications. Sorting mEPSC by rise time, a correlate of synapse location along dendrites, revealed amplitude raises at two separate domains. A specific frequency increase was observed in the same domains and was accompanied by a global, unspecific raise. Amplitude and frequency increments were lower at sites initially more active, consistent with local compensatory processes. Transient preincubation with a specific Ca2+/calmodulin-dependent kinase II (CaMKII) inhibitor either blocked or occluded amplitude and frequency upregulation in different synapse populations. Results are consistent with the concurrent development of different known CaMKII-dependent HSP processes. Our observations support that deafferentation causes rapid and diverse compensations resembling classical slow forms of adaptation to inactivity. These results may contribute to understand fast-developing homeostatic or pathological events after brain injury.

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Characterization of allelic variants is relevant to demonstrate associations among genetic background and susceptibility to develop cardiovascular diseases, which are the main cause of death in Chile. Association of APOB, APOE, and MTHFR polymorphisms with higher lipid levels and the risk of developing hypertension and cardiovascular diseases have been described. Thus, the aim of this study was to assess genotype distribution and relative allelic frequency of ApoB rs693, ApoE rs7412, ApoE rs429358, MTHFR rs1801131, and MTHFR rs1801133 allelic variants and their effects on lipid profile in young healthy men and women from Northern Chile. A group of 193 healthy subjects were enrolled for this study. Genotyping of rs693 (APOB), rs7412 and rs429358 (APOE), and rs1801131 and rs1801133 (MTHFR) polymorphisms were performed by real time PCR. In addition, lipid profiles were determined and associated to genetic data. The genotype distribution was APOB rs693 (CC = 37%, CT = 41%, and TT = 22%), APOE rs7412/rs429358 (E4 = 0.06, E3 = 0.91, and E2 = 0.03), MTHFR rs1801131 (AA = 57%, AC = 30%, and CC = 13%), and MTHFR rs1801133 (CC = 20%, CT = 47%, and TT = 33%). The association of the genetic variants with plasma lipid levels showed that women, but not men, carrying APOB mutated allele (T) and Apo E4 allele presented lower values of total cholesterol when compared with C/C homozygous genotype or E3 allele, respectively (p < 0.05). In addition, a subgroup analysis revealed that ApoB C/C homozygous women exhibited higher values of HDL-C when compared with men carrying identical genotype (p < 0.01). On the other hand, women carrying E4 allele exhibited lower values of triglycerides when compared with male carrying identical genotype (p < 0.05). Finally, women carrying mutate allele (C) for MTHFR rs1801131 showed lower levels of triglycerides when compared with A/A homozygous genotype (p < 0.05) and lower levels of LDL-C for MTHFR rs1801133 in females carrying (T) allele when compared with males carrying identical genotype (p < 0.05). In summary, the present data showed that APOB, APOE, and MTHFR single nucleotide polymorphisms are associated to lipid levels in a gender-dependent manner among healthy subjects from Northern Chile, especially in women.

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RESUMEN Se presenta el caso de un paciente de 50 años que refería un dolor crónico localizado debajo de la uña del dedo meñique, sin antecedente traumático, con cinco años de evolución y que limitaba su actividad laboral. El tumor glómico es de naturaleza benigna y se caracteriza por un dolor agudo circunscrito a región subungueal que se acrecienta a la presión y al frío, síntomas objetivos para sospecharlo. La mayor incidencia se observa en los adultos, aunque aparece con poca frecuencia, por lo que su identificación suele retardarse. El diagnóstico debe incluir exámenes de imágenes, entre los que destaca la ecografía, que es una excelente alternativa y muy accesible en diferentes poblaciones. En nuestro caso, la ecografía mostró la tumoración con nitidez, lo que fue determinante para elegir la exéresis quirúrgica como tratamiento. La evaluación anatomopatológica informó la existencia de tumor glómico. Luego de la cirugía, se comprobó alivio de los síntomas.

ABSTRACT We present the case of a 50-year-old patient who reported chronic pain under the nail of the little finger for five years, with no trauma history and which restricted his work activity. The glomus tumor is a benign neoplasm characterized by an acute and circumscribed pain in the subungual region that increases with pressure and cold, which are objective symptoms to suspect this condition. The highest incidence of glomus tumors occurs in adults; however, as it is infrequent, delayed diagnosis is common. The diagnosis must include imaging scans, especially ultrasound, which are an excellent and very accessible alternative in different populations. In our case, the tumor was clearly observed on the ultrasound images, which was crucial to choose the surgical excision as treatment. The anatomopathological evaluation revealed a glomus tumor and the subsequent relief of symptoms were confirmed after the surgery.

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RESUMEN Objetivo Medir la actitud emprendedora de los médicos especialistas en un hospital de Huancavelica, Perú. Determinar si la edad, sexo, tiempo de trabajo, modalidad de contrato, estado civil, ingresos económicos y especialidad influyen en su actitud emprendedora. Materiales y métodos Estudio observacional, prospectivo y transversal. Se aplicó un cuestionario calificado a escala de Likert a 32 médicos especialistas sobre actitud emprendedora y también se evaluaron la edad, el sexo, el tiempo de trabajo, el tipo de contrato, el estado civil, los ingresos económicos y la especialidad. Se hicieron análisis descriptivos e inferenciales. Resultados El 85 % mostró una sólida actitud emprendedora, y el 15 % podría ser emprendedor. Ningún participante descartó el emprendimiento como una opción. En la asociación de la actitud emprendedora y los factores estudiados no se encontraron diferencias significativas con ninguna variable. Conclusiones El 85 % de los médicos participantes tienen una actitud positiva hacia el emprendimiento, independientemente de los factores asociados estudiados.

ABSTRACT Objective To measure the entrepreneurial attitude of medical specialists at a hospital in Huancavelica, Peru. To determine if age, sex, job tenure, type of contract, marital status, income and medical specialty influence their entrepreneurial attitude. Materials and methods An observational, prospective and cross-sectional study. A Likert-scale questionnaire on entrepreneurial attitude was administered to 32 medical specialists. Also age, sex, job tenure, type of contract, marital status, income and medical specialty were assessed. Descriptive and inferential analyses were performed. Results Eighty-five percent (85 %) of the study population showed a solid entrepreneurial attitude, while the remaining 15 % might be an entrepreneur. No participant rejected entrepreneurship as an option. Regarding the association between the entrepreneurial attitude and the studied factors, no significant differences were found in any variable. Conclusions Eighty-five percent (85 %) of the study population showed a positive attitude towards entrepreneurship regardless of the studied associated factors.