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301.
Mohammad M Rahman Nhien T Luong Hozefa A Divan Christine Jesser Stephanie D Golz Kavita Thirumalai Aimee Reedy Guadalupe S Olivas 《Nicotine & tobacco research》2005,7(1):103-109
Vietnamese populations in Vietnam and the United States have a high prevalence of smoking. The associations among behavioral risk factors, acculturation, and smoking among the Vietnamese population living in the United States are not well documented. The present study aimed to identify the factors associated with smoking behavior among Vietnamese men living in Santa Clara County, California. A cross-sectional random-digit-dialed telephone survey was conducted. The sampling frame consisted of 27 Vietnamese surnames from the Santa Clara County telephone directory. A total of 660 adult respondents were interviewed to collect information on general health status, alcohol and tobacco use, HIV/AIDS, sexual behavior, injury control, hypertension, cholesterol screening, and acculturation. Of the 660 adults interviewed, 364 (55.2%) were male and 296 (44.8%) were female. Among males, 31.9% were current smokers, and among females, only one woman reported smoking. Univariate analyses revealed that having less than a college education, having poor English language skills, using Vietnamese at home and with friends, being less acculturated, not having a routine physical or blood cholesterol check, and being a binge drinker were significantly associated with an increased likelihood of smoking. Multivariate analysis revealed two independently associated factors: Respondents who were more acculturated were less likely to smoke (OR = 0.38, 95% CI = 0.18-0.83), and those not having cholesterol checked were more likely to smoke (OR = 2.48, 95% CI = 1.30-4.71). Acculturation level was inversely associated with smoking among Vietnamese adult men in Santa Clara County. Other health risk behaviors coexisted with smoking behavior and should be considered in prevention programs. 相似文献
302.
Guadalupe García-Llatas María Jesús Lagarda Fernando Romero Pedro Abellán Rosaura Farré 《Food chemistry》2007,101(3):1078-1086
The determination of two secondary lipid oxidation compounds (hexanal and pentane) in liquid infant foods using a headspace solid-phase microextraction gas chromatographic (HS-SPME-GC) method has been developed and validated. 相似文献
303.
Guadalupe Mndez‐Montealvo Jos L. Trejo‐Espino Octavio Paredes‐Lpez Luis A. Bello‐Prez 《Starch - St?rke》2007,59(6):277-283
The effect of nixtamalization on physicochemical and morphological characteristics of starch was studied. Determination of total starch, ash and amylose content, of swelling and solubility, gelatinization characteristics and morphological studies were carried out in starch isolated from native (S) and nixtamalized (NS) maize flours. Thermal analysis showed that nixtamalization produced starch annealing due to the higher gelatinization temperature obtained for NS. However, S had slightly lower enthalpy values. The swelling profile was similar for both starches, but the solubility values at the temperatures assessed were slightly higher in the NS samples. At temperatures below gelatinization, the granules showed the Maltese cross while at higher temperatures only ghost of granules were observed. The nixtamalized starch had larger granule sizes than the native starch, due to the partial swelling produced in the heating during the nixtamalization process. Larger granule sizes were also observed by image analysis, because major axis and area parameters were higher in NS samples than in S samples. The nixtamalization process produced changes in chemical, thermal and morphological characteristics, becoming important in products obtained from nixtamalized maize. 相似文献
304.
305.
Hakan Ferhatosmanoglu Ali Şaman Tosun Guadalupe Canahuate Aravind Ramachandran 《Distributed and Parallel Databases》2006,20(2):117-147
A common technique used to minimize I/O in data intensive applications is data declustering over parallel servers. This technique
involves distributing data among several disks so as to parallelize query retrieval and thus, improve performance. We focus
on optimizing access to large spatial data, and the most common type of queries on such data, i.e., range queries. An optimal
declustering scheme is one in which the processing for all range queries is balanced uniformly among the available disks.
It has been shown that single copy based declustering schemes are non-optimal for range queries. In this paper, we integrate
replication in conjunction with parallel disk declustering for efficient processing of range queries. We note that replication
is largely used in database applications for several purposes like load balancing, fault tolerance and availability of data.
We propose theoretical foundations for replicated declustering and propose a class of replicated declustering schemes, periodic allocations, which are shown to be strictly optimal for a number of disks. We propose a framework for replicated declustering, using a limited amount of replication and provide
extensions to apply it on real data, which include arbitrary grids and a large number of disks. Our framework also provides
an effective indexing scheme that enables fast identification of data of interest in parallel servers. In addition to optimal
processing of single queries, we show that this framework is effective for parallel processing of multiple queries. We present
experimental results comparing the proposed replication scheme to other techniques for both single queries and multiple queries,
on synthetic and real data sets.
Recommended by: Ahmed Elmagarmid
Supported by U.S. Department of Energy (DOE) Award No. DE-FG02-03ER25573, and National Science Foundation (NSF) grant CNS-0403342. 相似文献
306.
Nestor Belisario Gomez-Guzman Daniel Lopez-Dominguez Cinthya Dinorah Arrieta-Gonzalez Jan Mayen Eduardo Porcayo-Palafox Jose Guadalupe Chacon-Nava Jose Gonzalo Gonzalez-Rodriguez Jesus Porcayo-Calderon Roberto Ademar Rodriguez-Diaz 《International journal of molecular sciences》2022,23(14)
This study reports the behavior of the Ni20Cr alloy in molten nitrate salts. Its behavior was evaluated in the eutectic mixture called Solar Salt (binary salt) and in a ternary mixture (90% Solar Salt and 10% lanthanum nitrate). The addition of lanthanum nitrate was performed to determine if the presence of the La3+ cation could act as a corrosion inhibitor. Through mass loss and potentiodynamic polarization studies, the effects of both electrolytes on the corrosion resistance of the alloy at 300, 400, and 500 °C and at exposure times of 250, 500, 750, and 1000 h were determined. The results showed an increase in the corrosivity of the ternary salt, due to a decrease in its melting point and an increase in the concentration of nitrate ions. However, it was observed that the La3+ cations formed a protective layer (La2O3) on the alloy surface. In both corrosive media, the Ni20Cr alloy showed excellent corrosion resistance, due to its ability to form protective layers of Cr2O3, NiO, and NiCr2O4, in addition to the presence of a layer of La2O3 in the case of the ternary salt. 相似文献
307.
de Jesus CG dos Santos V Canestraro CD Zucolotto V Fujiwara ST Gushikem Y Wohnrath K Pessoa CA 《Journal of nanoscience and nanotechnology》2011,11(4):3499-3508
Nanostructured films comprising a 3-n-propylpyridinium silsesquioxane polymer (designated as SiPy+Cl-) and copper (II) tetrasulfophthalocyanine (CuTsPc) were produced using the Layer-by-Layer technique (LbL). To our knowledge this is the first report on the use of silsesquioxane derivative polymers as building blocks for nanostructured thin films fabrication. Deposition of the multilayers were monitored by UV-Vis spectroscopy revealing the linear increment in the absorbance of the Q-band from CuTsPc at 617 nm with the number of SiPy+Cl-/CuTsPc or CuTsPc/SiPy+Cl-bilayers. FTIR analyses showed that specific interactions between SiPy+Cl- and CuTsPc occurred between SO3- groups of tetrasulfophthalocyanine and the pyridinium groups of the polycation. Morphological studies were carried out using the AFM technique, which showed that the roughness and thickness of the films increase with the number of bilayers. The films displayed electroactivity and were employed to detection of dopamine (DA) and ascorbic acid (AA) using cyclic voltammetry, at concentrations ranging from 1.96 x 10(-4) to 1.31 x 10(-3) molL(-1). The number and the sequence of bilayers deposition influenced the electrochemical response in presence of DA and AA. Using differential pulse technique, films comprising SiPy+/-/CuTsPc were able to distinguish between DA and ascorbic acid (AA), with a potential difference of approximately with 500 mV, in the concentration range of 9.0 x 10(-5) to 2.0 x 10(-4) molL(-1), in pH 3.0. 相似文献
308.
Effect of Mexican Oregano (Lippia berlandieri Schauer) Essential Oil Fractions on the Growth of Aspergillus spp. in a Bread Model System 下载免费PDF全文
309.
José Juan Alvarado Flores María Liliana Ávalos Rodríguez Jorge Víctor Alcaraz Vera José Guadalupe Rutiaga Quiñones Santiago José Guevara Martínez Roberto Aguado Zarraga 《International Journal of Hydrogen Energy》2021,46(51):26152-26162
Regardless of the manufacturing process such as solid-state reaction, sol-gel, etc., applied in obtaining anodes in solid oxide fuel cells (SOFCs), Sr2MgMoO6-δ (SMMO) double perovskites are recognized worldwide and widely used as anodic material with potential application in SOFC. This is due to several factors such as high electronic conductivity, high electrocatalytic activity, structural stability under reducing atmosphere, high transition temperature, giant magnetoresistance, reasonable tolerance to carbon formation, and its desired ability to reduce sulfur poisoning. In this review article, the advances of the SMMO double perovskite are analyzed. 相似文献
310.
Caballero Pablo Ortiz Guadalupe Garcia-de-Prado Alfonso Boubeta-Puig Juan 《Multimedia Tools and Applications》2021,80(14):21101-21133
Multimedia Tools and Applications - In recent years, the evolution of smartphones and their software applications has grown exponentially; together with the advance of the Internet of Things and... 相似文献