4,232 research outputs found

    Manejo del material de siembra de yuca (Manihot esculenta Crantz)

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    Several cassava trials were planted at CIAT to study the effect of the maturity of stem cuttings, depth of planting, cutting length, planting position and the angle of the cut on root yield. Cuttings from the top and middle part of vigorous 1-yr-old plants produced greater than root yields than those proceeding from the lower part of the plant or from older stem parts. Cuttings planted vertically 10, 20 and 30 cm deep do not affect the yield but do affect root distribution, the no. of roots/plant and the difficulty of harvesting; planting at 10 cm in depth was the most adequate. Twenty-cm long, selected and treated cuttings gave slightly higher yields than 40 or 60 cm ones. Cuttings placed vertically assure more rapid emergence, greater than percentage of germination, greater than yields and prevent lodging in comparison to those planted in a horizontal or inclined position. When the stems were cut rectangularly or bevel-edged, different rooting systems were produced; the former produced roots with a more uniform distribution; nevertheless, yield was not affected. Vertical planting, either with a straight or bevel-edged cut, gave greater than yields than horizontal planting. To obtain max yields, planting material should be selected from the middle part of mature, vigorous plants, cut at right angles 20 cm long and planted vertically 10 cm deep. (AS-CIAT)Se sembraron varios ensayos de yuca en el CIAT para estudiar el efecto de la madurez de las estacas, profundidad de siembra, longitud de la estaca, posicion de siembra y angulo de corte de la misma, en el rendimiento de las raices. Las estacas de la parte media y superior de plantas vigorosas de un ano de edad produjeron mayores rendimientos de raices que aquellas provenientes de la parte baja de la planta o de estacas viejas. Las estacas sembradas verticalmente a 10, 20 y 30 cm de profundidad no influyen en el rendimiento, pero afectan la distribucion de raices, el numero de raices/planta y la facilidad de cosecha; la siembra a 10 cm de profundidad fue la mas adecuada. Las mayores estacas de 20 cm de largo seleccionadas y tratadas dieron rendimientos ligeramente mayores que las de 40 o 60 cm. La siembra vertical de las estacas aseguro una emergencia mas rapida, un mayor porcentaje de germinacion, mayores rendimientos y previno el volcamiento de las plantas, en comparacion con la posicion horizontal o inclinada. El corte de la estaca en forma rectangular o en bisel produjo diferentes sistemas de enraizamiento; el primero produce raices mas uniformemente distribuidas; sin embargo, no afecta el rendimiento. La siembra vertical, ya sea con angulo de corte recto o en bisel, da mayores rendimientos que la siembra horizontal. Para obtener los rendimientos maximos, el material de siembra se debe seleccionar de la parte media de plantas vigorosas maduras, cortado en un angulo recto, en trozos de 20 cm de largo y sembrado verticalmente a 10 cm de profundidad. (RA-CIAT

    Efecto del arreglo espacial de siembra en el rendimiento de las raices de yuca (Manihot esculenta)

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    Two trials were conducted at the CIAT expt station in Cali, Colombia, to measure the effect of spatial arrangement at fixed planting densities on cassava root yield. In expt I, 3 cassava cv. of different growth habit were planted at 10,000 plants/ha and arranged in 5 different patterns. Experiment II consisted of 3 different cassava cv. planted at 10,000 and 15,625 plants/ha, both densities arranged in a square and rectangular pattern. F-test and Duncan`s multiple range test showed no significant difference on root yield (P=0.05) due to spatial arrangement within a given density and a given cv. Different cv. yield different and there is an optimum planting density for a given cv. according to its growth habit. Agronomic implications suggegt that wider row spacings may enable easier weed control, allow easier management of mixed crops and leave uncultivated bands between rows to assist in controlling erosion on slopes, without significantly affecting root yield. (AS

    The new technology for cassava production

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    Cassava is a low-priority crop in agricultural development policies in most L.A. countries, limiting active research and extension activities. A description is given of CIAT-generated low- cost technology that can increase yields. This package consists of the visual selection of planting material; chemical treatment (fungicides + insecticides + micronutrients) of the selected cuttings; proper preparation of the cuttings (cut rectangularly at 20 cm, with 5-7 nodes) and planting vertically at a depth of 10 cm; and the use of high-yielding, adapted var. Cassava should be planted on ridges when soils are heavy textured with greater than 1200 mm rainfall/yr. On Oxisols and Vertisols, cassava should be fertilized with 1/2 t dolomitic lime and 1 t/ha 10-20-20NPK + 20S + 10Zn. In other soils, sufficient fertilizer to replace the nutrients extracted in the final product should be applied. Timely control of weeds is important. Pest-tolerant var. should be used; rotation or fallowing can also be practiced to break pest cycles. If disease-resistant material is not available, planting should be timed to avoid disease attack. Mechanical harvesting aids and storage of fresh roots are also discussed. (AS

    Producción de material de siembra de yuca

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    Impact of surface topography on the bacterial attachment to micro- and nano-patterned polymer films

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    The development of antimicrobial surfaces has become a high priority in recent times. There are two ongoing worldwide health crises: the COVID-19 pandemic provoked by the SARS-CoV-2 virus and the antibiotic-resistant diseases provoked by bacteria resistant to antibiotic-based treatments. The need for antimicrobial surfaces against bacteria and virus is a common factor to both crises. Most extended strategies to prevent bacterial associated infections rely on chemical based-approaches based on surface coatings or biocide encapsulated agents that release chemical agents. A critical limitation of these chemistry-based strategies is their limited effectiveness in time while grows the concerns about the long-term toxicity on human beings and environment pollution. An alternative strategy to prevent bacterial attachment consists in the introduction of physical modification to the surface. Pursuing this chemistry-independent strategy, we present a fabrication process of surface topographies [one-level (micro, nano) and hierarchical (micro+nano) structures] in polypropylene (PP) substrates and discuss how wettability, topography and patterns size influence on its antibacterial properties. Using nanoimprint lithography as patterning technique, we report as best results 82 and 86% reduction in the bacterial attachment of E. coli and S. aureus for hierarchically patterned samples compared to unpatterned reference surfaces. Furthermore, we benchmark the mechanical properties of the patterned PP surfaces against commercially available antimicrobial films and provide evidence for the patterned PP films to be suitable candidates for use as antibacterial functional surfaces in a hospital environment.This work is funded by the European Commission, under the project FLEXPOL (H2020-NMBPPILOT-2016-721062). The present study was carried out as part of a European project called “Antimicrobial FLEXible POLymers for its use in hospital environments” (FLEXPOL grant agreement No. 721062) funded by Horizon 2020 Framework Programme for Research and Innovation (2014-2020)

    A Study on Physical Exercise and General Mobility in People with Cerebral Palsy: Health through Costless Routines

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    [Abstract] Sedentary behavior (SB) is a common problem that may produce health issues in people with cerebral palsy (CP). When added to a progressive reduction in motor functions over time, SB can lead to higher percentages of body fat, muscle stiffness and associated health issues in this population. Regular physical activity (RPA) may prevent the loss of motor skills and reduce health risks. In this work, we analyzed data collected from 40 people (20 children and teenagers, and 20 adults) who attend two specialist centers in Seville to obtain an up-to-date picture regarding the practice of RPA in people with CP. Roughly 60% of the participants showed mostly mid/severe mobility difficulties, while 38% also had communicative issues. Most of the participants performed light-intensity physical activity (PA) at least once or twice a week and, in the majority of cases, had a neutral or positive attitude to exercising. In the Asociación Sevillana de Parálisis Cerebral (ASPACE) sample test, the higher the International Classification of Functioning, Disability and Health (ICF), the higher the percentage of negative responses to doing exercise. Conversely, in the Centro Específico de Educación Especial Mercedes Sanromá (CEEEMS), people likes PA but slightly higher ratios of positive responses were found at Gross Motor Function Classification System (GMFCS) levels V and II, agreeing with the higher personal engagement of people at those levels. We have also performed a literature review regarding RPA in CP and the use of low-cost equipment. As a conclusion, we found that RPA produces enormous benefits for health and motor functions, whatever its intensity and duration. Costless activities such as walking, running or playing sports; exercises requiring low-cost equipment such as elastic bands, certain smartwatches or video-games; or therapies with animals, among many others, have all demonstrated their suitability for such a purpose.This research was funded by the Spanish Ministry of Science and Innovation, State Plan 2017–2020: Challenges—R&D&I Projects with grant codes PID2019-104323RB-C32 and PID2019-104323RB-C33

    "Bioadsorption of silver ions by calcareous chitin, chitin and chitosan"

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    "Context: Calcareous chitin, chitin, chitosan, and their modifications are used as bioadsorbents of metals and dyes that cause environmental pollution, endocrine disruption, and human diseases. Aims: To evaluate the selective bioadsorption of silver ions (Ag+ ) by calcareous chitin, chitin, and chitosan. Methods: Experimental and prospective study. The presence of functional groups of the bioadsorbents was identified by Fourier-transformed infrared spectroscopy (FT-IR), 1H-NMR spectroscopy and scanning electron microscopy (SEM). The Langmuir, Freundlich, and Elovich models were applied to describe the adsorption capacity of bioadsorbents according to granule size (20-40, 40-60, 60-80 meshes) and temperature (10, 20, and 30°C). Results: The FT-IR spectrum of calcareous chitin indicates the presence of carbonate (CO3 = 1420 cm-1 ), amide III (1313 cm-1 ), –OH groups (3441.90 cm-1 ), and pyranose structure (952.83 cm-1 ); chitin has –OH groups (3441.90 cm-1 ), NH (3268 cm-1 ), amide I (1654 cm-1 ) and II (1559 cm-1 ); chitosan has –OH groups (3419.90 cm-1 ), –NH (3200 cm-1 ), amide I (1712.18 cm-1 ), –NH2 (1654.46 cm-1 ), amide III (1317.11 cm-1 ) and pyranose structure (1070.12 cm-1 and 1031 cm-1 ). The Langmuir model indicates greater bioadsorption of Ag+ ions at smaller particle sizes (60-80 = 0.25-0.18 mm) and at a temperature of 20-30°C. Conclusions: The bioadsorption of silver ions (Ag+ ) by chitosan is greater with respect to calcareous chitin and chitin; the Langmuir model fits for the Ag+ isotherm and suggests that the process is controlled by physisorption.

    Impact of HIV infection on sustained virological response to treatment against hepatitis C virus with pegylated interferon plus ribavirin

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    [Abstract] It is commonly accepted that human immunodeficiency (HIV) coinfection negatively impacts on the rates of sustained virological response (SVR) to therapy with pegylated interferon plus ribavirin (PR). However, this hypothesis is derived from comparing different studies. The aim of this study was to determine the impact of HIV coinfection on SVR to PR in one single population. In a multicentric, prospective study conducted between 2000 and 2013, all previously naïve hepatitis C virus (HCV)-infected patients who started PR in five Spanish hospitals were analyzed. SVR was evaluated 24 weeks after the scheduled end of therapy. Of the 1046 patients included in this study, 413 (39 %) were coinfected with HIV. Three hundred and forty-one (54 %) HCV-monoinfected versus 174 (42 %) HIV/HCV-coinfected patients achieved SVR (p < 0.001). The corresponding figures for undetectable HCV RNA at treatment week 4 were 86/181 (47 %) versus 59/197 (30 %), p < 0.001. SVR was observed in 149 (69 %) HCV genotype 2/3-monoinfected subjects versus 91 (68 %) HIV/HCV genotype 2/3-coinfected subjects (p = 0.785). In the HCV genotype 1/4-infected population, 188 (46 %) monoinfected patients versus 82 (30 %) with HIV coinfection (p < 0.001) achieved SVR. In this subgroup, absence of HIV coinfection was independently associated with higher SVR [adjusted odds ratio (95 % confidence interval): 2.127 (1.135–3.988); p = 0.019] in a multivariate analysis adjusted for age, sex, baseline HCV RNA load, IL28B genotype, fibrosis stage, and type of pegylated interferon. HIV coinfection impacts on the rates of SVR to PR only in HCV genotype 1/4-infected patients, while it has no effect on SVR in the HCV genotype 2/3-infected subpopulation.Instituto de Salud Carlos III; ISCIII-RETIC RD06/006Instituto de Salud Carlos III; ISCIII-RETIC RD12/0017Andalucía. Junta; PI-0492/2012Andalucía. Junta; AC-0095-201

    Nous serveis en la divulgació científica en ciències de la salut

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    Divulgació científica; Comunicació científica; Nous serveis bibliotecarisScientific outreach; Scientific communication; New library servicesDivulgación científica; Comunicación científica; Nuevos servicios bibliotecariosLa divulgació sempre ha estat una tasca inherent als serveis de les biblioteques. La Biblioteca Sant Joan de Déu pel seu context organitzatiu i concepció de serveis ha estat molt sensible a la comunicació i divulgació científica, més enllà de la comunicació i divulgació de col∙leccions i recursos científics. La missió de la Biblioteca Sant Joan de Déu és la de donar suport al aprenentatge, docència, recerca, innovació i gestió dels estudiants, profesors i professionals dels centres de Sant Joan de Déu, que engloben desde l’Escola Universitària d’Infermeria, a Hospitals (Sant Joan de Déu Barcelona o Parc Sanitari Sant Joan de Déu) a centres de foment de la recerca com la Fundació de Recerca Sant Joan de Déu. A més a més la Biblioteca es troba integrada en el Departament de Gestió del Coneixement i Comunicació Científica, el que fa que tot l’equip de Biblioteca i el de Comunicació estigui molt orientat al suport a l’activitat de recerca i sensibilitzat en el suport a la comunicació científica. Per tot això, i desde fa un parell d’anys la Biblioteca Sant Joan de Déu s’ha obert a nous serveis de divulgació científica on el seu paper aporta un valor interessant en la comunicació. En aquest sentit s’han portat a terme diferents serveis/projectes: 1. Divulgació de resultats de la recerca on l’equip de biblioteca té un paper proactiu en la detecció d’articles escrits pels nostres professionals i que els seus resultats poden ser interessants per la divulgació científica social. 2. Notícies científiques vs “fake news” on pensem que el bibliotecari pot aportar una visió professional del que són les fonts segures i fiables en ciències de la salut. 3. Medicina gráfica on s’està iniciant una col∙laboració per visualitzar el paper dels còmics i novel∙les gràfiques en el món de les ciències de la salut. Aquests projectes estàn en diferents graus d’implantació, per la qual cosa requereixen dun nivell d’assentament i consolidació que ens permetin en un futur proper una avaluació dels resultats i aportació dels mateixos

    UV-Casting on methacrylated PCL for the production of a peripheral nerve implant containing an array of porous aligned microchannels

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    Peripheral nerves are basic communication structures guiding motor and sensory information from the central nervous system to receptor units. Severed peripheral nerve injuries represent a large clinical problem with relevant challenges to successful synthetic nerve repair scaffolds as substitutes to autologous nerve grafting. Numerous studies reported the use of hollow tubes made of synthetic polymers sutured between severed nerve stumps to promote nerve regeneration while providing protection for external factors, such as scar tissue formation and inflammation. Few approaches have described the potential use of a lumen structure comprised of microchannels or microfibers to provide axon growth avoiding misdirection and fostering proper healing. Here, we report the use of a 3D porous microchannel-based structure made of a photocurable methacrylated polycaprolactone, whose mechanical properties are comparable to native nerves. The neuro-regenerative properties of the polymer were assessed in vitro, prior to the implantation of the 3D porous structure, in a 6-mm rat sciatic nerve gap injury. The manufactured implants were biocompatible and able to be resorbed by the host’s body at a suitable rate, allowing the complete healing of the nerve. The innovative design of the highly porous structure with the axon guiding microchannels, along with the observation of myelinated axons and Schwann cells in the in vivo tests, led to a significant progress towards the standardized use of synthetic 3D multichannel-based structures in peripheral nerve surgery
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