Aplicación de fertilizantes de liberación controlada al establecimiento de Pinus radiata en Valdivia

Thiers, O.; Gerding, V. Universidad Austral de Chile, Instituto de Silvicultura. Casilla 567, Valdivia, Chile. Leiva, F. Centro Experimental Forestal CEFOR, Universidad Austral de Chile. Casilla 567, Valdivia, Chile.Se evaluó el efecto de fertilizantes de liberación controlada (FLC) (Basacote® Plus 3M, 6M, 9M, y Starter; 10 a 20 g planta-1) en el período de establecimiento de plantaciones de Pinus radiata. Se instaló un ensayo con FLC y una mezcla de fertilizantes hidrosolubles (fertilización tradicional, 87 g planta-1) en tres sitios de la comuna de Valdivia, sobre suelos rojo arcillosos de la serie Los Ulmos (Typic Palehumult). Luego del primer año de evaluación los FLC y la fertilización tradicional permitieron crecimientos mayores (P 90 %) con y sin ellos. Los valores promedio en los mejores tratamientos alcanzaron: 70±16 cm (H), 16±4 mm de diámetro de cuello (DAC) y 194±12 cm3 de factor de producción (F = DAC2xH). La ganancia promedio de los árboles con FLC fue de 12 a 36 % en H y en DAC, y de 68 a 154 % en FP. La proporción de biomasa radicular (18 %) no fue modificada con las fertilizaciones. Los tratamientos con FLC presentaron ventajas operativas y de costos con respecto a la fertilización tradicional.Con aporte de COMPO AGRO Chile y CEFOR-UACh

Histochemical analyses of muscle injury induced by venom from Argentine Bothrops alternatus (víbora de la cruz)

Histochemical methods were used to study necrosis of skeletal muscle fibers induced by Bothrops alternatus snake venom from Argentina. Rats with a body weight between 220–270 g, were used. Animals received an i.m. venom injection (800 μg) in the gastrocnemius. To determine creatinphosphokinase activity (CPK), blood samples were taken from the tail 60 min, 3, 6, 12 and 24 h after the envenoming. About 24 h later, rats received chloral hydrate anesthesia for histological analysis with Hematoxilin–Eosin (H–E) stain, and histochemical studies such as lipid peroxidation (Schiff’s reaction), and calcium precipitation (alizarin red stain). Results showed an increment in plasma CPK level, with its major peak at 3 h. Histochemical analyses revealed an intense destruction of muscular fibers as a consequence of a significant lipid peroxidation and calcium precipitation as well. Histochemical methods can be considered as a valuable tool in applied research regarding toxicological problems such as snake venom intoxication. It can be concluded that B. alternatus snake venom leads to a lipid peroxidation accompanied by citoplasmatic calcium precipitation. In addition, it was demonstrated that H–E stain made on frozen cuts (histochemical technique) is effective to evidence a panoramic tissular view of muscular lesion caused by B. alternatus venom, with the advantage of demanding a shorter execution lapse (few hours) in relationship to classic H–E histological technique, which requires several days of procesing

Synthesis of a new polypyridinic highly conjugated ligand with electron-acceptor properties

A new acceptor polypyridinic ligand functionalized with a quinone fragment is reported. The ligand, dipyrido[3,2-a:2′,3′-c]-benzo[3,4]-phenazine-11,16-quinone, Nqphen, was synthesized by condensation of 1,10-phenanthroline-5,6-dione and 2,3-diamino-1,4-naphthoquinone. The syntheses of two rhenium complexes with this ligand are also reported

Web Browsing Behavior Analysis and Interactive Hypervideo

© ACM, 2013. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version was published in, ACM Transactions on the Web, Vol. 7, No. 4, Article 20, Publication date: October 2013.http://doi.acm.org/ 10.1145/2529995.2529996[EN] Processing data on any sort of user interaction is well known to be cumbersome and mostly time consuming. In order to assist researchers in easily inspecting fine-grained browsing data, current tools usually display user interactions as mouse cursor tracks, a video-like visualization scheme. However, to date, traditional online video inspection has not explored the full capabilities of hypermedia and interactive techniques. In response to this need, we have developed SMT 2ǫ, a Web-based tracking system for analyzing browsing behavior using feature-rich hypervideo visualizations. We compare our system to related work in academia and the industry, showing that ours features unprecedented visualization capabilities. We also show that SMT 2ǫ efficiently captures browsing data and is perceived by users to be both helpful and usable. A series of prediction experiments illustrate that raw cursor data are accessible and can be easily handled, providing evidence that the data can be used to construct and verify research hypotheses. Considering its limitations, it is our hope that SMT 2ǫ will assist researchers, usability practitioners, and other professionals interested in understanding how users browse the Web.This work was partially supported by the MIPRCV Consolider Ingenio 2010 program (CSD2007-00018) and the TIN2009-14103-C03-03 project. It is also supported by the 7th Framework Program of the European Commision (FP7/2007-13) under grant agreement No. 287576 (CasMaCat).Leiva Torres, LA.; Vivó Hernando, RA. (2013). Web Browsing Behavior Analysis and Interactive Hypervideo. ACM Transactions on the Web. 7(4):20:1-20:28. https://doi.org/10.1145/2529995.2529996S20:120:287

On the use of machine learning techniques and non-invasive indicators for classifying and predicting cardiac disorders

This research aims to enhance the classification and prediction of ischemic heart diseases using machine learning techniques, with a focus on resource efficiency and clinical applicability. Specifically, we introduce novel non-invasive indicators known as Campello de Souza features, which require only a tensiometer and a clock for data collection. These features were evaluated using a comprehensive dataset of heart disease cases from a machine learning data repository. Our findings highlight the ability of machine learning algorithms to not only streamline diagnostic procedures but also reduce diagnostic errors and the dependency on extensive clinical testing. Three key features—mean arterial pressure, pulsatile blood pressure index, and resistance-compliance indicator—were found to significantly improve the accuracy of machine learning algorithms in binary heart disease classification. Logistic regression achieved the highest average accuracy among the examined classifiers when utilizing these features. While such novel indicators contribute substantially to the classification process, they should be integrated into a broader diagnostic framework that includes comprehensive patient evaluations and medical expertise. Therefore, the present study offers valuable insights for leveraging data science techniques in the diagnosis and management of cardiovascular diseases.This research was partially supported by the National Council for Scientific and Technological Development (CNPq) through grant number 303192/2022-4 (R.O.); by FONDECYT grant number 1200525 (V.L.) from the National Agency for Research and Development (ANID) of the Chilean government under the Ministry of Science, Technology, Knowledge, and Innovation; and by Portuguese funds through the CMAT-Research Centre of Mathematics of University of Minho within projects UIDB/00013/2020 and UIDP/00013/2020 (C.C.)

Supersymmetric partners of the trigonometric Poschl-Teller potentials

The first and second-order supersymmetry transformations are used to generate Hamiltonians with known spectra departing from the trigonometric Poschl-Teller potentials. The several possibilities of manipulating the initial spectrum are fully explored, and it is shown how to modify one or two levels, or even to leave the spectrum unaffected. The behavior of the new potentials at the boundaries of the domain is studied.Comment: 20 pages, 4 figure

Characterization of the Chilean Public Procurement Ecosystem Using Social Network Analysis

Indexación: Scopus.'Mercado Público' is a Chilean electronic platform used for purchasing processes by Chilean public organizations for the last two decades. The main aim of this study is to characterize the Chilean public procurement ecosystem by using social network analysis to detect the main communities of suppliers based on who awarded the tenders. To do this, we use a methodology that first represents the bidder-supplier relationship as a bipartite graph using purchase order information. Then we project the bipartite graph onto a monopartite graph of suppliers. We end by detecting the main supplier communities using a modularity algorithm. When we applied this methodology to the large tender segment in the Chilean public procurement market over a period of four years, we successfully detected the five largest communities and the micro and small companies which had the greatest rate of participation over time.https://ieeexplore.ieee.org/document/914958

Superconformal mechanics and nonlinear supersymmetry

We show that a simple change of the classical boson-fermion coupling constant, $2\alpha \to 2\alpha n$, $n\in \N$, in the superconformal mechanics model gives rise to a radical change of a symmetry: the modified classical and quantum systems are characterized by the nonlinear superconformal symmetry. It is generated by the four bosonic integrals which form the so(1,2) x u(1) subalgebra, and by the 2(n+1) fermionic integrals constituting the two spin-n/2 so(1,2)-representations and anticommuting for the order n polynomials of the even generators. We find that the modified quantum system with an integer value of the parameter $\alpha$ is described simultaneously by the two nonlinear superconformal symmetries of the orders relatively shifted in odd number. For the original quantum model with $|\alpha|=p$, $p\in \N$, this means the presence of the order 2p nonlinear superconformal symmetry in addition to the osp(2|2) supersymmetry.Comment: 16 pages; misprints corrected, note and ref added, to appear in JHE

Cambios clínicos, hemáticos y coagulativos consecuentes al aumento de anticuerpos en equinos productores de suero antiofídico

El objetivo del trabajo consistió en estudiar los efectos clínicos, hemáticos y coagulativos, así como la producción de anticuerpos en tres equinos inmunizados para la producción de suero antiofídico monovalente contra Bothrops alternatus y evaluar los resultados obtenidos correlacionando la respuesta inmune humoral con el estado de salud de los animales. Los resultados indicaron que la inmunización de los equinos con el protocolo utilizado, indujo alteraciones clínicas menores y cambios en ciertos parámetros del hemograma y pruebas coagulativas. Se registraron variaciones de la capacidad neutralizante sobre distintos componentes del veneno, en especial las toxinas que afectan la coagulación de la sangre. Asimismo, se constató una correlación directa entre las tasas séricas de leucocitos y la producción de inmunoglobulinas. Los resultados indicaron que el período de descanso de un trimestre resulta extenso y causa una franca disminución del título de anticuerpos, perdiendo el suero capacidad neutralizante de la toxicidad del veneno; no obstante, al reanudar las inoculaciones los equinos presentaron una rápida reposición de los anticuerpos anti-toxinas de B. alternatus, tolerando altas dosis de veneno en el segundo período de inmunización

Acción del veneno de Bothrops diporus (yarará chica) del nordeste argentino sobre la hemostasia en diferentes mamíferos

Los venenos de serpientes inducen gran variedad de efectos sobre la coagulación sanguínea debido a sus componentes coagulantes y anticoagulantes. En este trabajo se estudió el efecto del veneno de Bothrops diporus de Argentina sobre el sistema hemostático en diferentes especies de mamíferos, determinándose las actividades coagulante, fibrinolítica y letal. Se pudo comprobar que el veneno de esta serpiente genera desórdenes de la coagulación sanguínea atribuibles a enzimas de tipo trombinas que inducen la transformación del fibrinógeno a fibrina, registrándose mayor susceptibilidad en las especies ovina y humana. La dosis coagulante mínima se comparó con venenos de víboras centroamericanas, surgiendo que las serpientes de zonas más cálidas poseen menor actividad coagulante