Metabolismo secundário e ligninas de espécies de Piper

O estudo químico das folhas e dos frutos de P. richardiaefolium resultou no isolamento de oito lignanas, sendo duas lignanas furofurânicas (sesamina e kobusina), quatro lignanas dibenzilbutirolactônicas (hinokinina, kusunokinina, arctigenina e haplomirfolina), duas lignanas dibenzilbutirolactólicas (cubebina e 3,4- dimetoxi-3,4-desmetilenodioxicubebina), dois cinamatos de bornila (ferulato de bornila e cumarato de bornila) e na identificação de duas amidas (piplartina e diidropiplartina). Das folhas de P. richardiaefolium foi extraído e analisado o óleo volátil. As estruturas das substâncias isoladas foram identificadas através de métodos espectroscópicos (RMN de 1H e de 13C e espectrometria de massas). O estudo de análise de componentes principais (PCA) das espécies Piper (P. truncatum - k 616, P. richardiaefolium - k 290, P. richardiaefolium - k 350, P. richardiaefolium - k 593, P. truncatum - k 597, P. pseudopotifolium - k 598, P. richardiaefolium - k 854, P. richardiaefolium - k 610, P. truncatum - k 112, P. pseudopotifolium - k 211 e P. cernuum - k 137) permitiu agrupar as espécies em dois grandes grupos e quatro subgrupos em relação à similaridade entre elas. Ligninas do caule de seis espécies de Piper foram extraídas utilizando o método de degradação de Klason e método de Bjorkman, e analisadas por métodos espectroscópicos (IV, RMN de 1H e de 13C). O método de degradação por oxidação por nitrobenzeno foi o escolhido para determinar a relação entre os monolignóis siringila e guaiacila. Os principais metabólitos das espécies estudadas foram comparados com os tipos de ligninas das mesmas espécies e os resultados sugeriram uma independência entre as vias biossintéticas de ligninas e lignanas.

Las expectativas hacia la integración de las TIC en educación desde una perspectiva fenomenológica

El presente artículo, desde una perspectiva fenomenológica, lleva a cabo una reflexión crítica en torno a las significaciones construidas socialmente en relación al uso de la tecnología, tomando como base las expectativas hacia la integración de las TIC, como predisposiciones que un determinado sujeto tiene para actuar. Se aboca a comprender, describir y profundizar en torno a las expectativas que profesores y estudiantes, como principales sujetos implicados de manera directa en el proceso de enseñanza-aprendizaje, tienen de las TIC como recursos de apoyo a la formación.

Unidades de medida utilizada en los tratamientos para reducir el peso y la obesidad: revisión sistemática

Existen diferentes tratamientos para reducir el sobrepeso y la obesidad; no obstante, los resultados de los tratamientos sobre la pérdida de peso tienen una expresión muy heterogénea. Objetivo: Determinar las unidades de medida más utilizadas en los tratamientos de pérdida de peso, mediante la revisión de artículos científicos. Método: Se ha realizado una revisión sistemática de los últimos 5 años en CINHAL, Proquest y Scopus. Se han seleccionado los artículos publicados en inglés, francés y español. Los criterios de inclusión han sido: artículos de tratamiento únicamente dietético del sobrepeso en humanos. Los criterios de exclusión: tratamientos no dietéticos, enfermedades metabólicas, menos de 50 pacientes y menos de 8 semanas de tratamiento. La revisión ha sido realizada por dos investigadores independientes. Resultados y discusión: De 854 artículos, sólo 61 cumplían con los criterios establecidos. Estos se agruparon en 5 subgrupos, según expresaban la pérdida, en kilos o en porcentajes. Los resultados muestran falta de homogeneidad en la expresión de dicha pérdida. Conclusiones: Existe una gran heterogeneidad en la expresión de los resultados de los tratamientos de pérdida de peso; la dieta es una de las herramientas menos usadas; el análisis de los ensayos clínicos de intervención refleja una alta calidad en los sujetos mayores de 18 años, destacando la carencia de este tipo de líneas de investigación en los menores de esa edad. Por ello, se deberían estandarizar las magnitudes de expresión del éxito de dichos tratamientos y aumentar las líneas de investigación sobre este tema.

Nile River & Red Sea Region, ca. 1870 (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Egypt, Arabia Petraea, and lower Nubia, by Keith Johnston. It was published by William Blackwood & Sons ; W. & K. Johnston, ca. 1870. Scale [ca. 1:2,854,868]. Covers the Nile River and Red Sea regions.The image inside the map neatline is georeferenced to the surface of the earth and fit to the Egypt Red Belt projected coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, territorial boundaries, shoreline features, roads, railroads, canals, wells, and more. Covers the Nile River and Red Sea regions.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

Does Money Matter in the Euro area? Evidence from a new Divisia Index. Bruegel Working Paper 2014/12, 6 November 2014

The purpose of this paper is to examine the possible role of money shocks on output and prices in the euro area. Since no Divisia monetary aggregates are available for the euro area, we first create and make available a database on euro-area Divisia monetary aggregates. We plan to update the dataset in the future and keep it publicly available. Using different SVAR models, we find sensible and statistically significant responses to Divisia money shocks, while the responses to simple-sum measures of money and interest rates are not statistically significant, and sometimes even the point estimates are not sensible.

El Conde Lucanor / compuesto por el excelentissimo principe don Iuan Manuel hiio del infante don Manuel y nieto del sancto rey don Fernando ; dirigido por Gonçalo de Argote y de Molina ...

Gonzalo Argote y de Molina es el ed. literario de la obra y sus propios escritos constan al v. de port. : Epistola dedicatoria ; Discurso al ... lector ; Vida de don Iuan Manuel ; Succession y linage de don Iuan Manuel ; Discurso de la poesia antigua Ca

(Table T1) Strontium isotopic composition and ages of limestone samples from ODP Hole 180-1118A

Limestone from Unit VI (857.1-859.15 meters below seafloor) collected at Site 1118 contains a planktonic foraminiferal fauna indicating a latest Miocene to early Pliocene age. Globorotalia tumida is recorded in Sample 180-1118A-68R-4, 46-48 cm, indicating an early Pliocene (N18) age at this level (J. Resig, pers. comm., 2000). Based on their known range in the western Papuan Basin, the presence of (rare) Lepidocyclina and common Amphistegina in some samples suggests that abundant shallow-water bioclastic debris present in these limestones may be reworked from older, possibly middle or early late Miocene sediments. Four samples were selected for whole-rock strontium isotopic analysis to further investigate this possibility. A petrographic examination of samples analyzed was also conducted.

Pliocene-Pleistocene stack of globally distributed benthic stable oxygen isotope records

We present a 5.3-Myr stack (the ''LR04'' stack) of benthic d18O records from 57 globally distributed sites aligned by an automated graphic correlation algorithm. This is the first benthic delta18O stack composed of more than three records to extend beyond 850 ka, and we use its improved signal quality to identify 24 new marine isotope stages in the early Pliocene. We also present a new LR04 age model for the Pliocene-Pleistocene derived from tuning the delta18O stack to a simple ice model based on 21 June insolation at 65 N. Stacked sedimentation rates provide additional age model constraints to prevent overtuning. Despite a conservative tuning strategy, the LR04 benthic stack exhibits significant coherency with insolation in the obliquity band throughout the entire 5.3 Myr and in the precession band for more than half of the record. The LR04 stack contains significantly more variance in benthic delta18O than previously published stacks of the late Pleistocene as the result of higher resolution records, a better alignment technique, and a greater percentage of records from the Atlantic. Finally, the relative phases of the stack's 41- and 23-kyr components suggest that the precession component of delta18O from 2.7-1.6 Ma is primarily a deep-water temperature signal and that the phase of d18O precession response changed suddenly at 1.6 Ma.

Solar radiation over and under sea ice during the POLARSTERN cruise ARK-XXVI/3 (TransArc) in summer 2011

Arctic sea ice has declined and become thinner and younger (more seasonal) during the last decade. One consequence of this is that the surface energy budget of the Arctic Ocean is changing. While the role of surface albedo has been studied intensively, it is still widely unknown how much light penetrates through sea ice into the upper ocean, affecting sea-ice mass balance, ecosystems, and geochemical processes. Here we present the first large-scale under-ice light measurements, operating spectral radiometers on a remotely operated vehicle (ROV) under Arctic sea ice in summer. This data set is used to produce an Arctic-wide map of light distribution under summer sea ice. Our results show that transmittance through first-year ice (FYI, 0.11) was almost three times larger than through multi-year ice (MYI, 0.04), and that this is mostly caused by the larger melt-pond coverage of FYI (42 vs. 23%). Also energy absorption was 50% larger in FYI than in MYI. Thus, a continuation of the observed sea-ice changes will increase the amount of light penetrating into the Arctic Ocean, enhancing sea-ice melt and affecting sea-ice and upper-ocean ecosystems.

Pacific Neogene carbonate accumulation rates

I have compiled CaCO3 mass accumulation rates (MARs) for the period 0-25 Ma for 144 Deep Sea Drilling Project and Ocean Drilling Program drill sites in the Pacific in order to investigate the history of CaCO3 burial in the world's largest ocean basin. This is the first synthesis of data since the beginning of the Ocean Drilling Program. Sedimentation rates, CaCO3 contents, and bulk density were estimated for 0.5 Myr time intervals from 0 to 14 Ma and for 1 Myr time intervals from 14 to 25 Ma using mostly data from Initial Reports volumes. There is surprisingly little coherence between CaCO3 MAR time series from different Pacific regions, although regional patterns exist. A transition from high to low CaCO3 MAR from 23-20 Ma is the only event common to the entire Pacific Ocean. This event is found worldwide. The most likely cause of lowered pelagic carbonate burial is a rising sea-level trend in the early Miocene. The central and eastern equatorial Pacific is the only region with adequate drill site coverage to study carbonate compensation depth (CCD) changes in detail for the entire Neogene. The latitude-dependent decrease in CaCO3 production away from the equator is an important defining factor of the regional CCD, which shallows away from the equatorial region. Examination of latitudinal transects across the equatorial region is a useful way to separate the effects of changes in carbonate production ('productivity') from changes in bottom water chemistry ('dissolution') upon carbonate burial.