Parkinson Disease (PD) primarily affects older adults. It is the second-most common neurodegenerative disease after Alzheimer's disease. Currently, more than 10 million people suffer from PD, and this number is expected to grow, considering the increasing global longevity.
View Article and Find Full Text PDFWorld population growth currently brings unequal access to food, whereas crop yields are not increasing at a similar rate, so that future food demand could be unmet. Many recent research works address the use of optimization techniques and technological resources on precision agriculture, especially in large demand crops, including climatic variables monitoring using wireless sensor networks (WSNs). However, few studies have focused on analyzing the dynamics of the environmental measurement properties in greenhouses.
View Article and Find Full Text PDFTomato greenhouses are a crucial element in the Equadorian economy. Wireless sensor networks (WSNs) have received much attention in recent years in specialized applications such as precision farming. The energy consumption in WSNs is relevant nowadays for their adequate operation, and attention is being paid to analyzing the affecting factors, energy optimization techniques working on the network hardware or software, and characterizing the consumption in the nodes (especially in the ZigBee standard).
View Article and Find Full Text PDFIn recent years, attention has been paid to wireless sensor networks (WSNs) applied to precision agriculture. However, few studies have compared the technologies of different communication standards in terms of topology and energy efficiency. This paper presents the design and implementation of the hardware and software of three WSNs with different technologies and topologies of wireless communication for tomato greenhouses in the Andean region of Ecuador, as well as the comparative study of the performance of each of them.
View Article and Find Full Text PDFThe intracardiac electrical activation maps are commonly used as a guide in the ablation of cardiac arrhythmias. The use of catheters with force sensors has been proposed in order to know if the electrode is in contact with the tissue during the registration of intracardiac electrograms (EGM). Although threshold criteria on force signals are often used to determine the catheter contact, this may be a limited criterion due to the complexity of the heart dynamics and cardiac vorticity.
View Article and Find Full Text PDFThis commentary is intended to find possible explanations for the low impact of computational modeling on pain research. We discuss the main strategies that have been used in building computational models for the study of pain. The analysis suggests that traditional models lack biological plausibility at some levels, they do not provide clinically relevant results, and they cannot capture the stochastic character of neural dynamics.
View Article and Find Full Text PDFOnline J Public Health Inform
April 2013
A comparative review is presented of available technologies suitable for automatic reading of patient identification bracelet tags. Existing technologies' backgrounds, characteristics, advantages and disadvantages, are described in relation to their possible use by public health care centers with budgetary limitations. A comparative assessment is presented of suitable automatic identification systems based on graphic codes, both one- (1D) and two-dimensional (2D), printed on labels, as well as those based on radio frequency identification (RFID) tags.
View Article and Find Full Text PDF[reaction: see text] The photoinduced metalation of nonactivated C-Cl bonds of O-acetyl chlorohydrins is promoted by samarium diiodide. As a result of this, beta-elimination of O-acetyl chlorohydrins is achieved, affording the corresponding (Z)-alkenes with total or high stereoselectivity.
View Article and Find Full Text PDFA samarium diiodide promoted addition of aromatic or aliphatic beta-substituted-alpha-halo-alpha,beta-unsaturated esters 1 or 3 to both ketones (in THF) and aldehydes (in acetonitrile) led to (Z)-2-(1-hydroxyalkyl)-2,3-alkenoates 2 and 4 in good yields and very high stereoselectivity. This method constitutes an efficient and valuable alternative to the synthesis of Baylis-Hillman adducts. A mechanism is proposed to explain this transformation.
View Article and Find Full Text PDFA new samarium diiodide-promoted addition reaction of vinylsamarium reagents, derived from (Z)-alpha-chloro-alpha,beta-unsaturated phenones 1, to both ketones (in THF) and aldehydes (in acetonitrile) led to (Z)-2-(1-hydroxyalkyl)-2,3-unsaturated ketones in good yield. These transformations took place with total or very high inversion of the stereochemistry of the C-C double bond of the starting chloroenone, producing the Z diastereoisomer. A new methodology to prepare SmI(2) in acetonitrile by sonic treatment of 1,2-diiodoethane with Sm powder is also described.
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