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Solar-climatic relationship and implications for hydrology

Research during the latest years has indicated a significant connection between climate and solar activity. Specifically, a relationship between Northern Hemisphere air temperature and sunspot cycle length (SCL) has been shown. By using monthly SCL and land air temperature from 1753-1990 (238 years) we show that this relationship also holds for a single observation point in south of Sweden. Using

Statistical atmospheric downscaling for rainfall estimation in Kyushu Island, Japan

The present paper develops linear regression models based on singular value decomposition (SVD) with the aim of downscaling atmospheric variables statistically to estimate average rainfall in the Chikugo River Basin, Kyushu Island, southern Japan, on a 12-hour basis. Models were designed to take only significantly correlated areas into account in the downscaling procedure. By using particularly pr

Forecasting discharge in Amazonia using artificial neural networks

The Amazon, located in northern South America, is the world's largest river basin, and covers an area of about 6.5 million km2. The observed interannual variability in precipitation and water availability during its main discharge season has been shown to be influenced by Pacific and Atlantic Ocean sea surface temperatures (SSTs). However, the links between large-scale atmospheric motion and local

Seasonal runoff forecast for northern South America : A statistical model

The variability of water availability in the Amazon Basin is highly related to the sea surface temperature (SST) pattern over the Atlantic and the Pacific Oceans. The possibility of forecasting this variability one season in advance is a necessity for the correct management of water in the region for water supply, energy production, and flood control. Here we present the development of a statistic

The relationships between tropical Pacific and Atlantic SST and northeast Brazil monthly precipitation

The monthly patterns of northest Brazil (NEB) precipitation are analyzed in relation to sea surface temperature (SST) in the tropical Pacific and Atlantic Oceans, using singular value decomposition. It is found that the relationships between precipitation and SST in both basins vary considerably throughout the rainy season (February-May). In January, equatorial Pacific SST is weakly correlated wit

Regionalization and spatial properties of Ceará State rainfall in northeast Brazil

The overall daily rainfall pattern of Ceará for 19 years, 1974-1992, was analyzed in terms of physiography and atmospheric circulation. This information was used to suggest a regionalization of the state's rainfall into homogeneous areas. The three large-scale precipitation mechanisms (Intertropical Convergence Zone, cold fronts, and upper air vortices) interact and create a certain rainfall patte

Lactic acid bacteria : From starter cultures to producers of chemicals

Lactic acid bacteria constitute a diverse group of industrially significant, safe microorganisms that are primarily used as starter cultures and probiotics, and are also being developed as production systems in industrial biotechnology for biocatalysis and transformation of renewable feedstocks to commodity- and high-value chemicals, and health products. Development of strains, which was initially

Impacts of silicon on biogeochemical cycles of carbon and nutrients in croplands

Crop harvesting and residue removal from croplands often result in imbalanced biogeochemical cycles of carbon and nutrients in croplands, putting forward an austere challenge to sustainable agricultural production. As a beneficial element, silicon (Si) has multiple eco-physiological functions, which could help crops to acclimatize their unfavorable habitats. Although many studies have reported tha

Microspectroscopy (μFTIR) reveals co-localization of lipid oxidation and amyloid plaques in human Alzheimer disease brains

Amyloid peptides are the main component of one of the characteristic pathological hallmarks of Alzheimer's disease (AD): senile plaques. According to the amyloid cascade hypothesis, amyloid peptides may play a central role in the sequence of events that leads to neurodegeneration. However, there are other factors, such as oxidative stress, that may be crucial for the development of the disease. In

Non-pharmacological Effects in Switching Medication : The Nocebo Effect in Switching from Originator to Biosimilar Agent

The nocebo effect is defined as the incitement or the worsening of symptoms induced by any negative attitude from non-pharmacological therapeutic intervention, sham, or active therapies. When a patient anticipates a negative effect associated with an intervention, medication or change in medication, they may then experience either an increase in this effect or experience it de novo. Although less

Effect of poly(propylene imine) glycodendrimers on β-amyloid aggregation in vitro and in APP/PS1 transgenic mice, as a model of brain amyloid deposition and Alzheimer's disease

Poly(propylene imine) (PPI) glycodendrimers are promising candidates as drug carriers and antiamyloidogenic and antiprionic agents. In this study the anti-β-amyloid capacity of PPI glycodendrimers of the fourth and fifth generations was investigated in vitro and in vivo. We assessed distinct PPI glycodendrimers including G4mDS and G5mDS, with electroneutral maltose shell, and G4mOS and G4m-IIIOS,

Dense shell glycodendrimers as potential nontoxic anti-amyloidogenic agents in Alzheimer's disease. Amyloid-dendrimer aggregates morphology and cell toxicity

Dendrimers have been proved to interact with amyloids, although most of dendrimers assayed in amyloidogenic systems are toxic to cells. The development of glycodendrimers, poly(propyleneimine) (PPI) dendrimers decorated with maltose (Mal), represents the possibility of using dendrimers with a low intrinsic toxicity. In the present paper we show that fourth (PPI-G4-Mal) and fifth (PPI-G5-Mal) gener

Granular non-fibrillar aggregates and toxicity in Alzheimer's disease

Granular non-fibrillar aggregates (GNAs) are identified as possible toxic species in Alzheimer's disease. GNAs form on the surface of negatively charged biological membranes and as a consequence of an acidic environment, off the polymerization pathway at neutral pH. Aβ (1-40) GNAs disturb the bilayer structure of model membranes and seem to be more toxic to cells with negatively charged membranes

Effect of Cimetidine on Survival after gastric cancer

The effect of cimetidine on survival was investigated in 181 patients with gastric cancer. Immediately after operation or the decision not to operate, the patients were randomised in double-blind fashion to placebo or cimetidine 400 mg twice daily for two years or until death, with review every three months. Median survival in the cimetidine group was 450 days (range 1-1826) and in the placebo gro

Predicting diagnosis and cognition with 18F-AV-1451 tau PET and structural MRI in Alzheimer's disease

Introduction: The relative importance of structural magnetic resonance imaging (MRI) and tau positron emission tomography (PET) to predict diagnosis and cognition in Alzheimer's disease (AD) is unclear. Methods: We tested 56 cognitively unimpaired controls (including 27 preclinical AD), 32 patients with prodromal AD, and 39 patients with AD dementia. Optimal classifiers were constructed using the