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1.
A standard method for the extraction of tiger nut milk has been introduced. It has been shown that, although milling duration improves the yield of tiger nut milk solids and its nutrient composition, there is a quantifiable loss of nutrient in the pressing residue during milk extraction. Milling duration improved the colloidal stability of the milk against creaming during 16 h of storage. A higher milling intensity resulted in the aggregation of biological polymers which resulted in colloidal destabilisation. Milling improved the lightness and stability and reduced browning rate of the tiger nut milk during storage. This report is important for the production of tiger nut milk of consistent and comparable characteristics. Milling has been introduced as a processing method for the qualitative and quantitative modulation of the properties of tiger nut milk. It is recommended to develop further strategies to improve the colloidal stability of tiger nut milk as a beverage.  相似文献   
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Water Resources Management - Overexploitation of groundwater in the Malayer Plain has resulted in a continuous decline of groundwater levels over recent years with associated risks to water...  相似文献   
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Understanding the sources and composition of organic aerosol (OA) in indoor environments requires rapid measurements, since many emissions and processes have short timescales. However, real-time molecular-level OA measurements have not been reported indoors. Here, we present quantitative measurements, at a time resolution of five seconds, of molecular ions corresponding to diverse aerosol-phase species, by applying extractive electrospray ionization mass spectrometry (EESI-MS) to indoor air analysis for the first time, as part of the highly instrumented HOMEChem field study. We demonstrate how the complex spectra of EESI-MS are screened in order to extract chemical information and investigate the possibility of interference from gas-phase semivolatile species. During experiments that simulated the Thanksgiving US holiday meal preparation, EESI-MS quantified multiple species, including fatty acids, carbohydrates, siloxanes, and phthalates. Intercomparisons with Aerosol Mass Spectrometer (AMS) and Scanning Mobility Particle Sizer suggest that EESI-MS quantified a large fraction of OA. Comparisons with FIGAERO-CIMS shows similar signal levels and good correlation, with a range of 100 for the relative sensitivities. Comparisons with SV-TAG for phthalates and with SV-TAG and AMS for total siloxanes also show strong correlation. EESI-MS observations can be used with gas-phase measurements to identify co-emitted gas- and aerosol-phase species, and this is demonstrated using complementary gas-phase PTR-MS observations.  相似文献   
4.
This study explored whether factors related to the work environment could predict changes in body mass index (BMI) and whether the effect of psychosocial factors was dependent on baseline BMI. The sample consisted of 1,980 male employees from the Danish National Work Environment Cohort Study. Changes in BMI between 1995 and 2000 were analyzed, by multiple regression, as a function of background variables and a series of occupational variables obtained in 1995. Age, baseline BMI, job insecurity, and psychological demands predicted changes in BMI. Job insecurity and high or low psychological demands increased the likelihood of weight gain among obese employees, whereas they increased the likelihood of weight loss among employees with a low BMI. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Balloon angioplasty as the treatment of first choice in the setting of an acute myocardial infarction (AMI) is gaining widespread acceptance because of favourable results from specialised centres concerning high patency rates and low mortality. This study reports the results of angioplasty for AMI at large community hospitals during 1992-1995. 4625 procedures were performed at 68 centres of the Arbeitsgemeinschaft Leitender Kardiologischer Krankenhaus?rzte (ALKK). The age of the patients was 60.8 +/- 11.3 years, with 75.1% men. The infarct related artery was the left anterior descendent in 43%, the right coronary artery in 37%, the circumflex artery in 16%, a bypass graft in 2.3% and the left main stem in 1.4% of patients. The success rate (residual stenosis < 50%) of the intervention was 86%. There was a wide range of procedures per centre, with a median of 40 AMI angioplasties per year and centre. The amount of angioplasties for AMI in relation to all angioplasties performed during this period rose from 5.2% in 1992 to 5.9% in 1995 (p = 0.01). Local complications at the puncture site occurred in 3.2%, with the need for a surgical intervention in 1.1% of patients. In 273 (5.9%) of the patients a second angioplasty was performed during the hospital stay. Aortocoronary bypass surgery was performed in 3% of the patients. Hospital mortality was 9.5% (438/4625 patients). The mortality rate remained constant during the years investigated (1992: 10.6%; 1993: 8.6%; 1994: 9.7%; 1995: 9.8%; p = ns). Higher mortality was observed in older patients, patients with multiple vessel disease, the left anterior descending artery or a bypass graft as infarct related artery as well as in patients with failed reperfusion (residual stenoses > 50%). Hospitals with a case load of more than 40 angioplasties for AMI per year showed a lower mortality as compared to the others. In clinical practice at large community hospitals results of angioplasty for AMI concerning mortality, complications and technical success rate are comparable to those of highly specialised centres. The absolute numbers of angioplasties for AMI increased constantly over the years.  相似文献   
7.
The quantitation of fluorescence radiance may at first suggest the need to obtain the number of fluorophore that are responsible for the measured fluorescence radiance. This goal is beset by many difficulties since the fluorescence radiance depends on three parameters 1) the probability of absorbing a photon (molar extinction), 2) the number of fluorophores, and 3) the probability of radiative decay of the excited state (quantum yield). If we use the same fluorophore in the reference solution and the analyte then, to a good approximation, the molar extinction drops out from the comparison of fluorescence radiance and we are left with the comparison of fluorescence yield which is defined as the product of fluorophore concentration and the molecular quantum yield. The equality of fluorescence yields from two solutions leads to the notion of equivalent number of fluorophores in the two solutions that is the basis for assignment of MESF (Molecules of Equivalent Soluble Fluorophore) values. We discuss how MESF values are assigned to labeled microbeads and by extension to labeled antibodies, and how these assignments can lead to the estimate of the number of bound antibodies in flow cytometer measurements.  相似文献   
8.
For the precise determination of the sizes of submicron beam spots test structures with an excellent edge definition are required. For this purpose a semiconductor heterostructure consisting of an 1.62 μm GaInP epi-layer grown on (0 0 1) GaAs has been made, which provides atomically sharp edges for beam spot size measurements. Since the sample has been thinned down by standard transmission electron microscope (TEM) preparation techniques, it can be used for both PIXE and STIM. The sample has been investigated with a TEM and the ion nanoprobe LIPSION. A one-dimensional beam profile in the low current mode was determined by a STIM measurement using 2 MeV protons and yielded a FWHM of (41±4) nm, which is the smallest value reported so far for high energy nuclear micro- and nanoprobes. Furthermore we present nickel nanowhiskers produced at the GSI Darmstadt by electrochemical preparation of etched ion track membranes that have been used to obtain two-dimensional images of the shapes of submicron beam spots. For these measurements a scan over a single nickel nanowhisker having a diameter of 220 nm and a height of about 6 μm was performed.  相似文献   
9.
An inulin syrup made from Jerusalem artichoke tubers, either in its commercial form or after ultrafiltration, was freeze-dried and used as a prebiotic ingredient in the small-scale manufacture of wafer crackers. The flours used for the preparation of wafer batters were from wheat, rye or spelt wheat, or 1:1 combinations of wheat flour and rye flour or wheat flour and spelt wheat flour. Batter viscosity was strongly influenced by the selection of the flour type, but remained within technologically acceptable limits. The ultrafiltration of the inulin syrup, using a 1 kDa membrane, resulted in a significant reduction of the content of free sugars and minerals which, in turn, had a significant impact on the CIE-Lab color values of the wafer crackers. Using spelt wheat flour instead of wheat flour significantly increased wafer cracker firmness measured by penetration, as did the incorporation of ultrafiltered freeze-dried instead of native freeze-dried Jerusalem artichoke syrup. Sensory analysis revealed a significant influence of product formulation on appearance, flavor and texture of the wafer crackers. It can be concluded from quality scores, which were calculated by using weighting factors assigned to the sensory attributes, that wheat flour may be partially replaced by rye flour or spelt wheat flour without negatively affecting the sensory properties of the wafer crackers.  相似文献   
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