3,034 research outputs found
High Resolution Spectrometry of Leaf and Canopy Chemistry for Biochemical Cycling
High-resolution laboratory spectrophotometer and Airborne Imaging Spectrometer (AIS) data were used to analyze forest leaf and canopy chemistry. Fundamental stretching frequencies of organic bonds in the visible, near infrared and short-wave infrared are indicative of concentrations and total content of nitrogen, phosphorous, starch and sugar. Laboratory spectrophotometer measurements showed very strong negative correlations with nitrogen (measured using wet chemistry) in the visible wavelengths. Strong correlations with green wet canopy weight in the atmospheric water absorption windows were observed in the AIS data. A fairly strong negative correlation between the AIS data at 1500 nm and total nitrogen and nitrogen concentration was evident. This relationship corresponds very closely to protein absorption features near 1500 nm
Studies on the clinical significance of nonesterified and total cholesterol in urine
Gas-liquid chromatographic determinations of nonesterified and total urinary cholesterol were performed in 137 normals, 264 patients with various internal diseases without evidence of neoplasias or diseases of the kidney or urinary tract, 497 patients with malignancies and 236 patients with diseases of the kidney, urinary tract infections or prostatic adenoma with residual urine. A normal range (mean±2 SD) of 0.2–2.2 mg/24 hours nonesterified cholesterol (NEC) and of 0.3–3.0 mg/24 hours total cholesterol (TC) was calculated.
Values of urinary cholesterol excretion were independent of age and sex and did not correlate with cholesterol levels in plasma. Patients with various internal diseases, without evidence of neoplasias nor diseases of the kidney or obstruction of the urinary tract, showed normal urinary cholesterol excretions, as did patients with infections of the urinary tract.
However, elevated urinary cholesterol was found in patients with diseases of the kidney or urinary tract obstruction (prostatic adenoma with residual urine), malignant diseases of the urogenital tract and metastasing carcinoma of the breast. In patients with other malignant diseases urinary cholesterol was usually normal.
Lesions of the urothelial cell membranes are considered to be the most likely cause of urinary cholesterol hyperexcretion. The clinical value of urinary cholesterol determinations as a possible screening test for urogenital carcinomas in unselected populations is limited by lacking specificity, expensive methodology and low prevalence of the mentioned carcinomas, although elevated urinary cholesterol excretions have been observed in early clinical stages of urogenital cancers
Production of Porous Alginate Substrates via Membrane Emulsification for Pharmaceutical Applications
The Food and Drug Administration (FDA) released in 2013 a report that established the pharmaceuticals current good manufacturing practices for the 21st century. This report encourages the creation of new technology in the pharmaceutical industry. Therefore, this research aims to develop a reliable method to produce porous polymers particles to be used in a novel continuous crystallization in porous substrate. The aim of the current work is to create porous polymer microspheres with uniform particle size distribution using a commercially available membrane emulsification system. In the present study, the emulsification was made using a dispersed phase composed of miglyol 840 and 2% w/w of span 80, and the aqueous phase composed of 2% w/w of alginate in deionized water and magnesium sulfate (MgSOÂÂ4). Membranes of different pore size (20 ÎĽm, 40 ÎĽm, and 60 ÎĽm) and material (stainless steel and nickel) were tested in order to observe the achievable particle size. A Tagushi design was evaluated considering three levels and four factors (MgSO4 concentration, rotation speed, flow rate, and temperature). The particle size and size distribution was obtained through image analysis of the dried particles. The mean size decreased as the rotation speed and flow rate increases. The temperature did not had a direct impact in the particle size but it reduces the time to generate the particles. No direct impact was observed by changing the MgSO4 concentration
Quantum walks on Cayley graphs
We address the problem of the construction of quantum walks on Cayley graphs.
Our main motivation is the relationship between quantum algorithms and quantum
walks. In particular, we discuss the choice of the dimension of the local
Hilbert space and consider various classes of graphs on which the structure of
quantum walks may differ. We completely characterise quantum walks on free
groups and present partial results on more general cases. Some examples are
given, including a family of quantum walks on the hypercube involving a
Clifford Algebra.Comment: J. Phys. A (accepted for publication
Diversidad de mariposas (Lepidoptera, Papilionoidea) y su relación con el paisaje de alta montaña en los Andes nororientales de Colombia
Diversitat de papallones (Lepidoptera, Papilionoidea) i la seva relaciĂł amb el paisatge d’alta muntanya als Andes nord-orientals de Colòmbia La regiĂł andina es caracteritza per acollir una gran varietat d’ecosistemes entre els quals es compten les caracterĂstiques zones d’alta muntanya, que mostren processos de transformaciĂł del sòl accelerats que han convertit els boscos natius en zones agrĂcoles i ramaderes, la qual cosa ha ocasionant un declivi de la diversitat biològica regional. L’ús d’indicadors de diversitat Ă©s adequat per avaluar els canvis en els paisatges d’alta muntanya i les papallones sĂłn un dels grups mĂ©s importants per determinar els canvis que es produeixen en els diferents tipus d’ambients. A l’à rea d’estudi es van establir dotze punts de mostreig als complexos d’erms d’Almorzadero, Santurbán i Tamá de la regiĂł nord-oriental de Colòmbia. Durant la fase de mostreig es van practicar captures d’individus adults de papallones en transsectes de 100 x 4 m en un gradient altitudinal de 500 m. Es van registrar 69 espècies, pertanyents a cinc famĂlies. Els valors de diversitat de la comunitat de papallones diĂĽrnes van variar a les diferents cobertures vegetals associades a cada transsecte. AixĂ, les Ă rees amb cobertura vegetal conservada (per exemple, bosc dens, arbustos i matolls i erm i suberm) van presentar els valors mĂ©s alts de diversitat, mentre que les zones amb cobertura alterada (per exemple, bosc fragmentat, pastures i Ă rees agrĂcoles) van presentar els valors de diversitat mĂ©s baixos. Les anĂ lisis d’estructura de comunitats evidencien que les espècies de papallones endèmiques estan associades a Ă rees fragmentades a les zones d’alta muntanya. Aquest estudi Ă©s el primer del seu tipus que estableix canvis en la diversitat de les papallones en zones d’alta muntanya del nord-est de Colòmbia i s’ha fet amb el propòsit de generar estratègies de conservaciĂł en llocs que presenten un alt grau d’endemisme i diversitat.Diversity of butterflies (Lepidoptera, Papilionoidea) and their relationship with the highlands’ landscape in the northeastern Andes of Colombia The Andean region harbors a great variety of ecosystems, including the characteristic high mountain zones. The biological diversity in these zones, however, is declining as the result of changes in land use, particularly the introduction of agriculture and cattle ranching. Changes in the high mountain landscape can be appropriately monitored using diversity indicators such as butterflies, one of the most important indicator species. We chose twelve sampling points in the paramo (high altitude moor) complexes Almorzadero, Santurbán and El Tamá, located in the northeastern region of Colombia to collect adult butterflies within transects of 100 x 4 m, along an altitudinal gradient of 500 m. We recorded 69 species, from five families. Diversity values of the diurnal butterfly communities varied among the different areas of vegetation coverage associated with each transect. Conserved vegetation coverage (i.e. dense forest, scrublands and scrublands, and paramo and subparamo) showed the highest values of diversity, while perturbed coverage (i.e. fragmented forests, pastures and agriculture areas) presented the lowest values of diversity. Analysis of the community structure showed that endemic butterfly species were associated with fragmented areas in the high mountains. Findings from this study, the first of its kind to determine changes in butterfly diversity in highlands in northeastern Colombia, may help to generate conservation strategies in places where there is high endemism and diversityLa regiĂłn andina se caracteriza por albergar una gran variedad de ecosistemas entre los que se cuentan las caracterĂsticas zonas de alta montaña, que muestran acelerados procesos de transformaciĂłn del suelo que han convertido los bosques nativos en zonas agrĂcolas y ganaderas ocasionando un declive de la diversidad biolĂłgica regional. El empleo de indicadores de diversidad es adecuado para evaluar los cambios en los paisajes de alta montaña, siendo las mariposas uno de los grupos más importantes para determinar los cambios que se producen en los diferentes tipos de ambientes. En el área de estudio se establecieron doce puntos de muestreo en los complejos de páramos del Almorzadero, Santurbán y Tamá de la regiĂłn nororiental de Colombia. Durante la fase de muestreo se realizaron capturas de individuos adultos de mariposas en transectos de 100 x 4 m en un gradiente altitudinal de 500 m. Se registraron 69 especies, pertenecientes a cinco familias. Los valores de diversidad de la comunidad de mariposas diurnas variaron en las diferentes coberturas vegetales asociadas a cada transecto. AsĂ, las áreas con cobertura vegetal conservada (por ejemplo, bosque denso, arbustos y matorrales y páramo y subpáramo) presentaron los valores más altos de diversidad, mientras que las zonas con cobertura alterada (por ejemplo, bosque fragmentado, pastos y áreas agrĂcolas) presentaron los valores de diversidad más bajos. Los análisis de estructura de comunidades evidencian que las especies de mariposas endĂ©micas están asociadas a áreas fragmentadas en las zonas de alta montaña. Este estudio es el primero de su tipo que establece cambios en la diversidad de las mariposas en zonas de alta montaña del nordeste de Colombia y se ha realizado con el propĂłsito de generar estrategias de conservaciĂłn en lugares que presentan un alto grado de endemismo y diversidad
Formation, stability and antioxidant activity of food-grade multilayer emulsions containing resveratrol
Interfacial deposition of biopolymer layers on oil droplets may be a suitable strategy for increasing the emulsion stability and protection of functional ingredients. Resveratrol is a naturally occurring phenolic compound with numerous health-promoting properties, but its usage is still restricted due to its poor water solubility and high chemical instability. The aim of this study was to formulate single-layer (lactoferrin) and multilayer (lactoferrin/alginate and lactoferrin/alginate/-poly-l-lysine) emulsions containing resveratrol and to study the emulsions stability and antioxidant activity during storage. All primary (single-layer) emulsions had average droplet diameters below 300Â nm and -potentials strongly positive, allowing the electrostatic deposition of another layer of anionic biopolymer, such as alginate. Secondary (multilayer) emulsions were highly unstable at low alginate concentrations, which was attributed to the bridging flocculation. At higher alginate concentrations, secondary emulsions were rather stable. Tertiary emulsions containing either low or high -poly-l-lysine concentrations presented flocculation, but formulations with 0.0036% (w/w) were fairly stable. The antioxidant activity of all resveratrol-loaded emulsions did not significantly change during storage, whereas it decreased in non-encapsulated resveratrol oil from the third week onwards. This study provides useful information for the design of delivery systems for resveratrol with relevance in food applications.This research was supported by the Ministerio de Ciencia e InnovaciĂłn (Spain) throughout the projects AGL2009-11475 and ALG2012-35635, and by the Portuguese Foundation for Science and
Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684), Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-
FEDER-027462) and FCT Strategic Project of UID/BIO/04469/2013 unit. The authors also thank the Project “BioInd - Biotechnology and Bioengineering for improved Industrial and Agro-Food processes,
REF. NORTE-07-0124-FEDER-000028” Co-funded by the Programa
Operacional Regional do Norte (ON.2 e O Novo Norte), QREN,
FEDER. The author A. Acevedo-Fani thanks the University of Lleida for the pre-doctoral grant. The author H. D. Silva, (SFRH/BD/81288/2011) is the recipient of a fellowship from the Fundação para a Ciência e Tecnologia (FCT, Portugal). The authors would like to acknowledge to Rui Fernandes from IBMC, University of Porto, for assistance in taking the TEM microphotographs.info:eu-repo/semantics/publishedVersio
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