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101.
The authenticity of 91 wines produced in Cyprus from both indigenous and other vine varieties were investigated by a holistic approach, using, advanced technology such as SNIF-NMR (site-specific natural isotopic fractionation-nuclear magnetic resonance) and 1R-MS (isotope ratio-mass spectrometry) for the determination of the stable isotopes and ICP (inductively coupled plasma spectroscopy) for some heavy metals. The spectroscopic characteristics were evaluated statistically using different chemometric methods. The dependency of the D/H (deuterium/hydrogen) ratio of the methylene site in the ethanol molecule (D/H)ll and also theδ ^18O values of the wine water, were the most useful discriminators. Isotopic results allow us to have a complete idea about the regional variability of the isotopes. Among the metals, Ni followed by Pb was the ones with the highest discrimination value. The determined concentrations of Pb, Ni, Cr and Cd that are related to the safety of wines were within the acceptable limits that have been established by the OIV (international organization of vine and wine) or comparable with the results of the wines of other European countries. The study of the correlation between the load of heavy metals and isotopes in wines showed a dependence on the grape variety but not the geographical location of the vineyard. This is probably due to the close proximity of wine regions in Cyprus.  相似文献   
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103.
This paper provides evidence that it is possible to migrate structured system designs to UML models. Legacy structured designs can be converted to object-oriented systems without losing data or functionality. The reason for choosing UML is that it is the new standard notation, which tries to build on and integrate object-oriented notations. Extracts from a case study are presented together with the proposed guidelines for the re-engineering process.  相似文献   
104.
The application of fluorescence confocal laser scanning microscopy (CLSM) to quantify three-dimensional pH gradients near electrode surfaces is described. The methodology utilizes a trace quantity of a fluorescent dye, fluorescein, in solution, which fluoresces strongly above pH 6.5, to map the pH adjacent to various ultramicroelectrodes undergoing electrochemical processes that lead to pH changes. The experimental fluorescence profiles, determined by CLSM, have been compared to models by solving the underlying mass transport equations, including the effect of natural convection, using the finite element method. The methodology has been validated through studies of the galvanostatic reduction of water at both disk and ring ultramicroelectrodes. The fluorescence profiles were found to be highly sensitive to both the initial bulk solution pH and applied current in a predictable fashion. The potentiostatic reduction of oxygen has been investigated at 25- and 10-microm-diameter platinum electrodes to confirm the effective number of electrons transferred in the reaction. Finally, the application of this methodology to observe defects in microelectrode arrays, particularly those that cannot be seen by optical microscopy, is described.  相似文献   
105.
Electrospray ionization (ESI) is extensively used in the analysis of biological compounds; yet some fundamental properties of this technique are not completely understood. It is widely recognized that care should be exercised when noncovalent complexes are being studied by ESI, since weak noncovalent binding can be broken or formed during the desolvation process. In the present work, spectra from the noncovalent complex, vancomycin/diacetyl-L-lysyl-D-alanyl-D-alanine, obtained from ESI and from nanoelectrospray ionization (nanoESI), have been compared. The results indicated that the milder desolvation conditions arising as a result of the smaller sizes of droplets produced in the nanoESI source attenuated effects upon weak bonds in the desolvation process. The association constant values calculated from the relative peak intensities suggest that, when using ESI, the analyzed noncovalent complex dissociated in the condensed phase during the spraying process. The influences of experimental parameters such as tip diameter and coating for nanoESI needles were investigated. Principal component analysis, a multivariate analysis method, was applied to achieve a better evaluation of the spectra obtained using different needle diameters and coatings for the analysis of the noncovalent complex vancomycin/diacetyl-L-lysyl-D-alanyl-D-alanine. It was found that 2-microm tip diameter resulted in more reproducible spectra than the larger tip diameters tested (6-20 microm).  相似文献   
106.
The aims of this work were to examine the attitudes of individuals with visual impairments towards distance education (DE) and the relationships between attitudes and participants’ personal characteristics. Forty-one adults with visual impairments, who ranged in age from 20 to 40, participated in this study. A self-constructed questionnaire measuring the attitudes towards DE was employed. The participants’ answers revealed slightly positive emotions towards DE according to the affective component of attitudes, slightly positive attitudes when DE is compared with traditional education, and positive attitudes as far as the cognitive component of attitudes and participants’ intention to participate in a DE programme were concerned. The elder participants seem to have more positive attitudes towards DE compared with younger participants. Furthermore, the greater the level of education, the more positive were the attitudes towards DE, and the greater the frequency of computer usage, the more positive were the attitudes towards DE. The analysis of the data collected revealed that the sample of individuals with visual impairments had slightly positive attitudes towards DE. Age, level of education, and frequency of computer usage were found to be significant predictors of the participants’ attitudes.  相似文献   
107.
The increased operational tempo associated with current deployments to Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) is placing considerable strain on military families. Among other sequelae of OIF and OEF deployment, findings from recent studies suggest high rates of depression in spouses of service members. This review presents a rationale for targeting depression among military spouses. It examines how stressors relating to the deployment cycle may contribute to depression in spouses and outlines the effects of spousal depression on the mental health of service members and their children. Mental health services currently available to military spouses as well as barriers to their care are also described. Considerations for the adaptation of treatment to their unique circumstances and needs are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
108.
Striped mullet (Mugil cephalus) roe is used for the production of high nutritional and added-value delicacies. Its lipid fraction is rich in polyunsaturated fatty acids (PUFA) and bioactive compounds. This study examines scalable oil extraction methods for mullet roe oil extraction. Namely, solvent extraction (SE) using ethanol in two different temperatures, supercritical fluid extraction (SFE) using CO2-ethanol mixture (SFE-E) in two different temperatures, expeller oil press (EP) extraction, expeller oil press combined with ethanol extraction (EP-SE) and wet reduction (WR) are examined. The methods are evaluated with regard to the oil yield and recovery, the oil oxidation and the composition in fatty acids, and polar compounds and unsaponifiable matter. EP-SE and SE provide the highest oil recovery for tested extraction temperatures (76% and 65% respectively), followed by SFE-E (46%) and EP (36%). Extracted oils present high PUFA content (28.5–33.9%). The type of extraction process and the process variables affect oil oxidation as well as the concentration of polar compounds and unsaponifiable matter. In terms of oxidation levels, 85% of the extracted oil samples were within the limits set by the Codex Alimentarius Commission. The potential of the examined methods for industrial mullet roe oil production is discussed. Practical applications : Oil rich in polyunsaturated fatty acids was extracted from stripped mullet roe. The work proposes several scalable extraction methods using mild conditions which could be applied to obtain edible and high nutritional value mullet roe oil with high recovery reaching up to 76%. The same methods could be employed also for mullet roe by-products. The obtained results improve the knowledge regarding the potential of roe valorization for oil extraction as well as the effect of the extraction method on the oil yield, main composition features and the quality characteristics of oil extracted by mullet roe. This research could offer new opportunities for the food industry for fish roe valorization for high nutritional quality oil production.  相似文献   
109.
Medical discoveries mainly depend on the capability to process and analyze biological datasets, which inundate the scientific community and are still expanding as the cost of next-generation sequencing technologies is decreasing. Deep learning (DL) is a viable method to exploit this massive data stream since it has advanced quickly with there being successive innovations. However, an obstacle to scientific progress emerges: the difficulty of applying DL to biology, and this because both fields are evolving at a breakneck pace, thus making it hard for an individual to occupy the front lines of both of them. This paper aims to bridge the gap and help computer scientists bring their valuable expertise into the life sciences. This work provides an overview of the most common types of biological data and data representations that are used to train DL models, with additional information on the models themselves and the various tasks that are being tackled. This is the essential information a DL expert with no background in biology needs in order to participate in DL-based research projects in biomedicine, biotechnology, and drug discovery. Alternatively, this study could be also useful to researchers in biology to understand and utilize the power of DL to gain better insights into and extract important information from the omics data.  相似文献   
110.
While exercise benefits a wide spectrum of diseases and affects most tissues and organs, many aspects of its underlying mechanistic effects remain unsolved. In vitro exercise, mimicking neuronal signals leading to muscle contraction in vitro, can be a valuable tool to address this issue. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for this systematic review and meta-analysis, we searched EMBASE and PubMed (from database inception to 4 February 2022) for relevant studies assessing in vitro exercise using electrical pulse stimulation to mimic exercise. Meta-analyses of mean differences and meta-regression analyses were conducted. Of 985 reports identified, 41 were eligible for analysis. We observed variability among existing protocols of in vitro exercise and heterogeneity among protocols of the same type of exercise. Our analyses showed that AMPK, Akt, IL-6, and PGC1a levels and glucose uptake increased in stimulated compared to non-stimulated cells, following the patterns of in vivo exercise, and that these effects correlated with the duration of stimulation. We conclude that in vitro exercise follows motifs of exercise in humans, allowing biological parameters, such as the aforementioned, to be valuable tools in defining the types of in vitro exercise. It might be useful in transferring obtained knowledge to human research.  相似文献   
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