1,255 research outputs found
Valoración económica como estrategia de recuperación de espacios naturales. Estudio de caso “La Aguada En Francisco J. Mujica, México” / Economic valuation as a strategy for the recovery of natural areas. Case study “La Aguada In Francisco J. Mujica, México”
Durante la fundación de la comunidad, Francisco J. Mujica, la laguna “La Aguada” fue de suma importancia para satisfacer las necesidades básicas de suministro de agua de los habitantes así, como la obtención de alimento. Con el pasar de los años y el establecimiento de la red de agua potable dentro de las viviendas, la laguna fue quedando en el abandono con el consecuente deterioro. La conservación de cuerpos de agua se torna importante para la sustentabilidad de la comunidad.El objetivo de este proyecto fue realizar la valoración económica de la laguna “La Aguada”, caracterizar las condiciones en que se encuentra para diagnosticar las acciones necesarias para su restauración, mantenimiento y conservación. Se utilizó el método de valoración contingente que consiste en determinar el valor que otorgan las personas al medio ambiente ante un cambio en sus condiciones, para calcular la disponibilidad a pagar (DAP), se utilizaron dos métodos: la Media según Kaplan-Meier-Turnbull y la Media según Interpolación lineal. Se concluye que, existe una vinculación social con la aguada, como recurso natural importante para el desarrollo comunitario. Se visualiza la recuperación de la laguna para fines productivos, específicamente la pesca con una disponibilidad a pagar promedio de 96.41 pesos mensuales. Los habitantes son personas participativas, mostraron interés en rehabilitar la laguna y mostraron disponibilidad a realizar aportes tanto monetario como en jornales para la restauración, protección y mantenimiento de “La Aguada”
Percepción social de las reservas naturales en Ejidos de Quintana Roo: Social perception of natural reserves in Ejidos de Quintana Roo
Los Ejidos forestales de Quintana Roo se han caracterizado por establecer y mantener áreas de conservación de forma voluntaria entre ellos están Bacalar, X-Hazil y Felipe Carrillo Puerto. En estas áreas se concentra una gran diversidad de flora y fauna que han persistido hasta la actualidad. Las reservas se encuentran en sitios prioritarios y de conservación para muchas organizaciones a nivel regional, nacional e internacional. La permanencia de estas reservas territoriales depende de la visión de protección que tengan los dueños de la selva, por lo que el objetivo de esta investigación es medir la percepción de los habitantes respecto a los recursos naturales que se encuentran en las reservas para medir la permanencia de las mismas. Para conocer la percepción de los ejidatarios sobre los recursos naturales se realizó una consulta pública en la que se cuestionó sobre el conocimiento e importancia de las áreas naturales para determinar si las áreas de conservación ejidal son conocidas y valoradas y si están conscientes de los atributos de Alto Valor de Conservación de acuerdo a los criterios establecidos por el FSC. Los resultados señalan que el estado de conservación de los sitios es bueno, con tendencias a seguir mejorando pues la vegetación se está recuperando de forma natural, además funciona como un refugio de especies. Existen acuerdos de protección a largo plazo, los cuales son conocidos y respetados. Esto incluye limitar las actividades permitidas solo a observación y no al aprovechamiento, por lo que existe una garantía de conservación a largo plazo. 
The Main Belt Comets and ice in the Solar System
We review the evidence for buried ice in the asteroid belt; specifically the questions around the so-called Main Belt Comets (MBCs). We summarise the evidence for water throughout the Solar System, and describe the various methods for detecting it, including remote sensing from ultraviolet to radio wavelengths. We review progress in the first decade of study of MBCs, including observations, modelling of ice survival, and discussion on their origins. We then look at which methods will likely be most effective for further progress, including the key challenge of direct detection of (escaping) water in these bodies
Characterising the KMP-11 and HSP-70 recombinant antigens' humoral immune response profile in chagasic patients
11 pages, 6 figures.-- The pre-publication history for this paper can be accessed
here:
http://www.biomedcentral.com/1471-2334/9/186/pre
pubBackground: Antigen specificity and IgG subclass could be significant in the natural history of
Chagas' disease. The relationship between the different stages of human Chagas' disease and the
profiles of total IgG and its subclasses were thus analysed here; they were directed against a crude
T. cruzi extract and three recombinant antigens: the T. cruzi kinetoplastid membrane protein-11
(rKMP-11), an internal fragment of the T. cruzi HSP-70 protein192-433, and the entire Trypanosoma
rangeli HSP-70 protein.
Methods: Seventeen Brazilian acute chagasic patients, 50 Colombian chronic chagasic patients (21
indeterminate and 29 cardiopathic patients) and 30 healthy individuals were included. Total IgG and
its subtypes directed against the above-mentioned recombinant antigens were determined by
ELISA tests.
Results: The T. cruzi KMP-11 and T. rangeli HSP-70 recombinant proteins were able to distinguish
both acute from chronic chagasic patients and infected people from healthy individuals. Specific
antibodies to T. cruzi crude antigen in acute patients came from IgG3 and IgG4 subclasses whereas
IgG1 and IgG3 were the prevalent isotypes in indeterminate and chronic chagasic patients. By
contrast, the specific prominent antibodies in all disease stages against T. cruzi KMP-11 and T. rangeli
HSP-70 recombinant antigens were the IgG1 subclass.This work was supported by Colciencias Research project No. 1203-333-
18692. IDF was supported by Colciencias and the Universidad Javeriana's
Young Researcher 2008 Programme (Bogotá, Colombia). MCT and MCL
were supported by P06-CTS-02242 Grant from PAI (Junta de Andalucia)
and RICET-RD06/0021-0014, Spain. MS received financial support from the
Brazilian agency - CNPq.Peer reviewe
Intra- and extracellular β-amyloid overexpression via adeno-associated virus-mediated gene transfer impairs memory and synaptic plasticity in the hippocampus
Alzheimer's disease (AD), the most common age-related neurodegenerative disorder, is currently conceptualized as a disease of synaptic failure. Synaptic impairments are robust within the AD brain and better correlate with dementia severity when compared with other pathological features of the disease. Nevertheless, the series of events that promote synaptic failure still remain under debate, as potential triggers such as β-amyloid (Aβ) can vary in size, configuration and cellular location, challenging data interpretation in causation studies. Here we present data obtained using adeno-associated viral (AAV) constructs that drive the expression of oligomeric Aβ either intra or extracellularly. We observed that expression of Aβ in both cellular compartments affect learning and memory, reduce the number of synapses and the expression of synaptic-related proteins, and disrupt chemical long-term potentiation (cLTP). Together, these findings indicate that during the progression AD the early accumulation of Aβ inside neurons is sufficient to promote morphological and functional cellular toxicity, a phenomenon that can be exacerbated by the buildup of Aβ in the brain parenchyma. Moreover, our AAV constructs represent a valuable tool in the investigation of the pathological properties of Aβ oligomers both in vivo and in vitro
Perspectives on utilization of edible coatings and nano-laminate coatings for extension of postharvest storage of fruits and vegetables
It is known that in developing countries, a large quantity of fruit and vegetable losses results at postharvest and processing stages due to poor or scarce storage technology and mishandling during harvest. The use of new and innovative technologies for reducing postharvest losses is a requirement that has not been fully covered. The use of edible coatings (mainly based on biopolymers) as a postharvest technique for agricultural commodities has offered biodegradable alternatives in order to solve problems (e.g., microbiological growth) during produce storage. However, biopolymer-based coatings can present some disadvantages such as: poor mechanical properties (e.g., lipids) or poor water vapor barrier properties (e.g., polysaccharides), thus requiring the development of new alternatives to solve these drawbacks. Recently, nanotechnology has emerged as a promising tool in the food processing industry, providing new insights about postharvest technologies on produce storage. Nanotechnological approaches can contribute through the design of functional packing materials with lower amounts of bioactive ingredients, better gas and mechanical properties and with reduced impact on the sensorial qualities of the fruits and vegetables. This work reviews some of the main factors involved in postharvest losses and new technologies for extension of postharvest storage of fruits and vegetables, focused on perspective uses of edible coatings and nano-laminate coatings.María L. Flores-López thanks Mexican Science and Technology Council (CONACYT, Mexico) for PhD fellowship support (CONACYT Grant Number: 215499/310847). Miguel A. Cerqueira (SFRH/BPD/72753/2010) is recipient of a fellowship from the Fundação para a Ciência e Tecnologia (FCT, POPH-QREN and FSE Portugal). The authors also thank the FCT Strategic Project of UID/ BIO/04469/2013 unit, the project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and the project ‘‘BioInd Biotechnology and Bioengineering for improved Industrial and AgroFood processes,’’ REF. NORTE-07-0124-FEDER-000028 Co-funded by the Programa Operacional Regional do Norte (ON.2 – O Novo Norte), QREN, FEDER. Fundação Cearense de Apoio ao Desenvolvimento Científico e Tecnológico – FUNCAP, CE Brazil (CI10080-00055.01.00/13)
Bacteria-inducing legume nodules involved in the improvement of plant growth, health and nutrition
Bacteria-inducing legume nodules are known as rhizobia and belong to the class Alphaproteobacteria and Betaproteobacteria. They promote the growth and nutrition of their respective legume hosts through atmospheric nitrogen fixation which takes place in the nodules induced in their roots or stems. In addition, rhizobia have other plant growth-promoting mechanisms, mainly solubilization of phosphate and production of indoleacetic acid, ACC deaminase and siderophores. Some of these mechanisms have been reported for strains of rhizobia which are also able to promote the growth of several nonlegumes, such as cereals, oilseeds and vegetables. Less studied are the mechanisms that have the rhizobia to promote the plant health; however, these bacteria are able to exert biocontrol of some phytopathogens and to induce the plant resistance. In this chapter, we revised the available data about the ability of the legume nodule-inducing bacteria for improving the plant growth, health and nutrition of both legumes and nonlegumes. These data showed that rhizobia meet all the requirements of sustainable agriculture to be used as bio-inoculants allowing the total or partial replacement of chemicals used for fertilization or protection of crops
Measurement of inclusive and differential cross sections for single top quark production in association with a W boson in proton-proton collisions at = 13 TeV
Measurements of the inclusive and normalised differential cross sections are presented for the production of single top quarks in association with a W boson in proton-proton collisions at a centre-of-mass energy of 13 TeV. The data used were recorded with the CMS detector at the LHC during 2016-2018, and correspond to an integrated luminosity of 138 fb. Events containing one electron and one muon in the final state are analysed. For the inclusive measurement, a multivariate discriminant, exploiting the kinematic properties of the events is used to separate the signal from the dominant background. A cross section of 79.2 ± 0.9 (stat) (syst) ± 1.2 (lumi) pb is obtained, consistent with the predictions of the standard model. For the differential measurements, a fiducial region is defined according to the detector acceptance, and the requirement of exactly one jet coming from the fragmentation of a bottom quark. The resulting distributions are unfolded to particle level and agree with the predictions at next-to-leading order in perturbative quantum chromodynamics
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