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51.
52.
David W. Eby Nina M. Silverstein Lisa J. Molnar David LeBlanc Geri Adler 《Accident; analysis and prevention》2012
According to the Alzheimer's Association (2011), (1) in 8 people age 65 and older, and about one-half of people age 85 and older, have Alzheimer's disease in the United States (US). There is evidence that drivers with Alzheimer's disease and related dementias are at an increased risk for unsafe driving. Recent advances in sensor, computer, and telecommunication technologies provide a method for automatically collecting detailed, objective information about the driving performance of drivers, including those with early stage dementia. The objective of this project was to use in-vehicle technology to describe a set of driving behaviors that may be common in individuals with early stage dementia (i.e., a diagnosis of memory loss) and compare these behaviors to a group of drivers without cognitive impairment. Seventeen drivers with a diagnosis of early stage dementia, who had completed a comprehensive driving assessment and were cleared to drive, participated in the study. Participants had their vehicles instrumented with a suite of sensors and a data acquisition system, and drove 1–2 months as they would under normal circumstances. Data from the in-vehicle instrumentation were reduced and analyzed, using a set of algorithms/heuristics developed by the research team. Data from the early stage dementia group were compared to similar data from an existing dataset of 26 older drivers without dementia. The early stage dementia group was found to have significantly restricted driving space relative to the comparison group. At the same time, the early stage dementia group (which had been previously cleared by an occupational therapist as safe to drive) drove as safely as the comparison group. Few safety-related behavioral errors were found for either group. Wayfinding problems were rare among both groups, but the early stage dementia group was significantly more likely to get lost. 相似文献
53.
The standardisation of packaging and containers for product handling has potential benefits from transportation, material handling and environmental perspectives. Likewise, standardised modular containers play an important role in the Physical Internet (PI). To support implementation of standard modular containers, we introduce a mathematical model to select a requisite number of modular containers to pack a set of products to maximise space utilisation. A decomposition-based solution methodology is developed and presented. Computational results from industry-based problem instances indicate that using standardised modular containers results in increased space utilisation at the unit load level. This finding substantiates the use of modular containers in moving toward the PI. 相似文献
54.
Temporal generalization allows a trained classification algorithm to be applied to multiple images across time to derive reliable classification map products. It is a challenging remote-sensing research topic since the results are dependent on the selection of atmospheric correction methods, classification algorithms, validation processes, and their varying combinations. This study examined the temporal generalization of sub-pixel vegetation mapping using multiple Landsat images (1990, 1996, 2004, and 2010). All Landsat images were processed with two atmospheric correction methods: simple dark object subtraction (DOS) and the Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS) algorithm. For the sub-pixel vegetation mapping of the 2004 Landsat image, we used high-resolution OrbView-3 images as a training/validation data set and compared three machine learning algorithms (neural networks, random forests, and classification and regression trees) for their classification performance. The trained classifiers were then applied to other Landsat images (1990, 1996, and 2010) to derive sub-pixel vegetation map products. For the 2004 Landsat image classification, cross-validation shows similar classification results for neural networks (root mean square error (RMSE) = 0.099) and random forests (RMSE = 0.100) algorithms, and both are better than classification and regression trees (RMSE = 0.123). Pseudo-invariant pixels between 2004 and 2010 were used as validation points to evaluate the temporal generalizability of classification algorithms. Simple DOS and LEDAPS atmospheric correction resulted in similar accuracy statistics. The neural-network-based classifier performed best in generating reliable sub-pixel vegetation map products across time. 相似文献
55.
Andrea Ianni Denise Innosa Camillo Martino Lisa Grotta Francesca Bennato Giuseppe Martino 《Journal of dairy science》2019,102(4):2918-2927
Zinc represents an essential microelement for several biochemical mechanisms. The body's inability to store zinc necessarily requires a constant dietary supply to avoid alteration of physiological functions. The aim of the present study was to investigate the effect of dietary enrichment with zinc on chemical-nutritional and aromatic properties of milk and cheese. Thirty commercial dairy cows, balanced for parity, milk production, and days in milk, were randomly assigned to 2 groups. The control group was fed with a conventional complete diet (22 kg of dry matter/animal per day), whereas the experimental group received a daily zinc supplementation of 60 mg per kg of dry complete feed. During the experimental period, the milk yield was monitored and samples of milk and caciotta cheese were collected to obtain information about the chemical-nutritional composition and aromatic profile. Dietary zinc integration did not influence milk yield and composition, but induced a marked reduction of somatic cell count and improved the oxidative stability of ripened caciotta cheese. In both milk and cheese, the experimental group samples were characterized by a lower concentration of saturated fatty acids and an increase in oleic acid, vaccenic acid, and rumenic acid. The aromatic profile of dairy products was also positively affected by dietary zinc intake, with an increase in concentration of carboxylic acids, aldehydes, and esters. The present results suggest a positive role of zinc in improving animal health and nutraceutical properties of milk and corresponding cheese. Taking into account the analysis of volatile compounds, zinc dietary supplementation of dairy cows should contribute to the production of cheeses with interesting organoleptic properties, although more studies are necessary to confirm the consumer acceptability of these changes. 相似文献
56.
Jessica Mendes Nadal Mona Lisa Simionatto Gomes Débora Maria Borsato Martinha Antunes Almeida Fernanda Malaquias Barboza Sônia Faria Zawadzki 《Drug development and industrial pharmacy》2016,42(11):1813-1824
This article aimed to improve the relative solubility and dissolution rate of ferulic acid (FA) by the use of spray-dried solid dispersions (SDs) in order to ensure its in vitro antioxidant potential and to enhance its in vivo anti-platelet effect. These SDs were prepared by spray-drying at 10 and 20% of drug concentration using polyvinylpyrrolidone K30 (PVP-K30), polyethylene glycol 6000 (PEG 6000) and poloxamer-188 (PLX-188) as carriers. SDs and physical mixtures (PM) were characterized by SEM, XRPD, FTIR spectroscopy and TGA analysis. Spray-dried SDs containing FA were successfully obtained. Relative solubility of FA was improved with increasing carrier concentration. PVP-K30 and PEG 6000 formulations showed suitable drug content values close to 100%, whereas PLX-188 presented mean values between 70 and 90%. Agglomerates were observed depending on the carrier used. XRPD patterns and thermograms indicated that spray-drying led to drug amorphization and provided appropriate thermal stability, respectively. FTIR spectra demonstrated no remarkable interaction between carrier and drug for PEG 6000 and PLX-188 SDs. PVP-K30 formulations had changes in FTIR spectra, which denoted intermolecular O–H???O?=?C bonds. Spray-dried SDs played an important role in enhancing dissolution rate of FA when compared to pure drug. The free radical-scavenging assay confirmed that the antioxidant activity of PEG 6000 10% SDs was kept. This formulation also provided a statistically increased in vivo anti-platelet effect compared to pure drug. In summary, these formulations enhanced relative solubility and dissolution rate of FA and chosen formulation demonstrated suitable in vitro antioxidant activity and improved in vivo anti-platelet effect. 相似文献
57.
Giuseppe Ateniese Alfredo De Santis Anna Lisa Ferrara Barbara Masucci 《Journal of Cryptology》2012,25(2):243-270
A time-bound hierarchical key assignment scheme is a method to assign time-dependent encryption keys to a set of classes in a partially ordered hierarchy, in such a way
that each class can compute the keys of all classes lower down in the hierarchy, according to temporal constraints. 相似文献
58.
59.
Karina Pombo García Kristof Zarschler Lisa Barbaro José A. Barreto William O'Malley Leone Spiccia Holger Stephan Bim Graham 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(13):2516-2529
Nanoparticles represent highly promising platforms for the development of imaging and therapeutic agents, including those that can either be detected via more than one imaging technique (multi‐modal imaging agents) or used for both diagnosis and therapy (theranostics). A major obstacle to their medical application and translation to the clinic, however, is the fact that many accumulate in the liver and spleen as a result of opsonization and scavenging by the mononuclear phagocyte system. This focused review summarizes recent efforts to develop zwitterionic‐coatings to counter this issue and render nanoparticles more biocompatible. Such coatings have been found to greatly reduce the rate and/or extent of non‐specific adsorption of proteins and lipids to the nanoparticle surface, thereby inhibiting production of the “biomolecular corona” that is proposed to be a universal feature of nanoparticles within a biological environment. Additionally, in vivo studies have demonstrated that larger‐sized nanoparticles with a zwitterionic coating have extended circulatory lifetimes, while those with hydrodynamic diameters of ≤5 nm exhibit small‐molecule‐like pharmacokinetics, remaining sufficiently small to pass through the fenestrae and slit pores during glomerular filtration within the kidneys, and enabling efficient excretion via the urine. The larger particles represent ideal candidates for use as blood pool imaging agents, whilst the small ones provide a highly promising platform for the future development of theranostics with reduced side effect profiles and superior dose delivery and image contrast capabilities. 相似文献
60.
Dan A. Buzatu Willie M. Cooper Christine Summage-West John B. Sutherland Anna J. Williams Deborah A. Bass Lisa L. Smith Robert S. Woodruff Jessica M. Christman Steven Reid Randal K. Tucker Christopher J. Haney Ashfaqe Ahmed Fatemeh Rafii Jon G. Wilkes 《Food microbiology》2013
A flow cytometric method (RAPID-B™) with detection sensitivity of one viable cell of Escherichia coli serotype O157:H7 in fresh spinach (Spinacia oleracea) was developed and evaluated. The major impediment to achieving this performance was mistaking autofluorescing spinach particles for tagged target cells. Following a 5 h non-selective enrichment, artificially inoculated samples were photobleached, using phloxine B as a photosensitizer. Samples were centrifuged at high speed to concentrate target cells, then gradient centrifuged to separate them from matrix debris. In external laboratory experiments, RAPID-B and the reference method both correctly detected E. coli O157:H7 at inoculations of ca. 15 cells. In a follow-up study, after 4 cell inoculations of positives and 6 h enrichment, RAPID-B correctly identified 92% of 25 samples. The RAPID-B method limit of detection (LOD) was one cell in 25 g. It proved superior to the reference method (which incorporated real time-PCR, selective enrichment, and culture plating elements) in accuracy and speed. 相似文献