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Mostrando ítems 330-349 de 360
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Ternary complex formation of phosphate with Ca and Mg ions binding to ferrihydrite: Experiments and mechanisms
(2020-03-25)Calcium (Ca) and magnesium (Mg) are the most abundant alkaline-earth metal ions in nature, and their interaction with ferrihydrite (Fh) affects the geochemical cycling of relevant ions, including phosphate (PO4). The ... -
Tetraaquabis(2,3-dihydro-1,4-benzodioxine-2-carboxylato)calcium(II)
(2020)The acid–base reaction of 1,4-benzodioxane 2-carboxylic acid with calcium carbonate furnished the centrosymmetric title compound, [Ca(C9H7O4)2(H2O)4], in which the metal ion is octahedrally coordinated by two monodentate ... -
The Bacterial Product Violacein Exerts an Immunostimulatory Effect Via TLR8
(2019)Violacein, an indole-derived, purple-colored natural pigment isolated from Chromobacterium violaceum has shown multiple biological activities. In this work, we studied the effect of violacein in different immune cell lines, ... -
The Combined Use of Alphavirus Replicons and Pseudoinfectious Particles for the Discovery of Antivirals Derived from Natural Products
(2015)Alphaviruses are a prominent class of reemergent pathogens due to their globally expanding ranges, potential for lethality, and possible use as bioweapons. The absence of effective treatments for alphaviruses highlights ... -
The geomicrobiology of iron, cobalt, nickel and manganese in lateritic tropical soils from the Santa Elena Peninsula, Costa Rica
(2019)There is an increasing interest in the biogeochemistry of metals, like cobalt, fuelled by the growing need for batteries and other high technology products. Bioprocessing of Co has been proposed to improve its recovery ... -
The potential of Pseudomonas for bioremediation of oxyanions
(2021-12)Non-metal, metal and metalloid oxyanions occur naturally in minerals and rocks of the Earth’s crust and are mostly found in low concentrations or confined in specific regions of the planet. However, anthropogenic activities ... -
The putative phosphate transporter PitB (PP1373) is involved in tellurite uptake in Pseudomonas putida KT2440
(2020)Tellurium oxyanions are chemical species of great toxicity and their presence in the environment has increased because of mining industries and photovoltaic and electronic waste. Recovery strategies for this metalloid that ... -
The role of chloramine species in NDMA formation
(2018-09)N-nitrosodimethylamine (NDMA), a probable human carcinogen disinfection by-product, has been detected in chloraminated drinking water systems. Understanding its formation over time is important to control NDMA levels in ... -
Thermische und Photochemische Umlagerungen an λ5-Phosphorinen
(1973-05-22)Durch Zweistufenoxydation der λ5-Phosphorine 4 und 5 wurden die neuen λ5-Phosphorine 7, 21 und 23 - 28 synthetisiert. Das 2,4-Diphenyl-6-t-butyl- λ5-phosphorin (5), das 2,4-Diphenyl-6-t-butyl-pyrylium-tetrafluoroborat (2) ... -
Three new species of Gliocephalotrichum causing fruit rot on different hosts from Brazil
(2020-09-18)The genus Gliocephalotrichum (Nectriaceae), originally described as a soil-borne fungus, has been associated with postharvest diseases, especially of tropical fruits. Taxonomic studies using both morphological and molecular ... -
Titration-Based Screening for Evaluation of Natural Product Extracts: Identification of an Aspulvinone Family of Luciferase Inhibitors
(2011)The chemical diversity of nature has tremendous potential for the discovery of molecular probes and medicinal agents. However, sensitivity of HTS assays to interfering components of crude extracts derived from plants, and ... -
Transcriptional control of 2,4-dinitrotoluene degradation in Burkholderia sp. R34 bears a regulatory patch that eases pathway evolution
(2021-05)The dnt pathway of Burkholderia sp. R34 is in the midst of an evolutionary journey from its ancestral, natural substrate (naphthalene) towards a new xenobiotic one [2,4-dinitrotoluene (DNT)]. The gene cluster encoding ... -
Transformation of presumptive precursors to frontalin and exo-brevicomin by bark beetles and the West Indian sugarcane weevil (Coleoptera)
(1996-03)(Z)-6-Nonen-2-one (1) has recently been shown to be the biosynthetic precursor for the aggregation pheromone exo-brevicomin (2) in mountain pine beetle (MPB) males, Dendroctonus ponderosae (Hopkins). We tested the hypotheses ... -
Tropical Atmospheric Corrosion of Galvanized Steel, in a light urban atmosphere in the San José Valley of Costa Rica
(2022)Costa Rica imports most of the metallic materials it uses. In construction, Galvanized Steel (GS) is one of the most used elements in urban areas, where atmospheric corrosion is the main problem of its environmental ... -
Uncovering the Cultivable Microbial Diversity of Costa Rican Beetles and Its Ability to Break Down Plant Cell Wall Components
(2014)Coleopterans are the most diverse insect order described to date. These organisms have acquired an array of survival mechanisms through their evolution, including highly efficient digestive systems. Therefore, the coleopteran ... -
Unusual Microbial Xylanases from Insect Guts
(2004-06-07)Recombinant DNA technologies enable the direct isolation and expression of novel genes from biotopes containing complex consortia of uncultured microorganisms. In this study, genomic libraries were constructed from microbial ... -
UPLC-HRMS Polyphenolic Characterization, Contents and Antioxidant Activity of Zingiber officinale Roscoe rhizomes from Costa Rica
(2022)Zingiber offcinale Roscoe rhizomes have been associated with multiple health benefits, such as blocking blood clotting, digestive and antinausea effects and aid in respiratory conditions. These effects have been linked ... -
Use of a theoretical prediction method and quantum chemical calculations for the design, synthesis and experimental evaluation of three green corrosion inhibitors for mild steel
(2020)Three phenylmethanimine derivatives (Schiff bases) were designed after a theoretical prediction of their corrosion inhibition efficiencies and a corroboration through the use of quantum chemical calculations. The molecules ... -
Using Student Profiles to Motivate and Understand How to Attract Women to Computer Science
(2020)This article reports how to build and analyze student profiles to influence the perception that girls and young women have of the profession, and of the diverse work opportunities that exist in Computer Science in Costa ... -
El Uso de Plaguicidas en América Latina: Tendencias e implicaciones ambientales (Memoria Encargada)
(1988)The current demand for pesticides in Latin America exceeds US $ 2000 million in value. Up to 1990, consumption is expected to rise by 7 to 12%. The use of pesticides has been fully accepted in Lati America as a readily ...