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Storage Conditions (storage + condition)
Kinds of Storage Conditions Selected AbstractsEFFECT OF DIFFERENT STORAGE CONDITIONS ON THE LIPID FRACTION OF A VEGETABLE CREAMJOURNAL OF FOOD QUALITY, Issue 4 2008FEDERICO FERIOLI ABSTRACT Fatty acids (free and esterified), diglycerides, peroxides and total sterols were determined in a vegetable cream. Cream samples were analyzed when fresh and after storage for 3 and 6 months at 4, 15, 30C and room temperature (10,25C). The product showed a higher amount of unsaturated fatty acids (,50% of total fatty acids) with respect to milk fat and a low level of cholesterol (<0.01%). The phytosterol content (,14 mg/100 g of cream) was not high enough to contribute to a decrease in cholesterolemia. Lipid oxidation remained low during storage (peroxides: 2.0,3.0 meq O2/kg of fat), but a small increase was observed at room temperature after 6 months (about 6.0 meq O2/kg of fat). Free fatty acids never exceeded 0.3% of fat. Storage at 4C and 15C delayed lipolysis in comparison to storage at 30C and room temperature. PRACTICAL APPLICATIONS The analysis of a vegetable cream demonstrated that it was a shelf-stable product, showing a high stability toward lipid oxidation and lipolysis. Such a product might be employed as vehicle for healthy fat compounds like long-chain polyunsaturated fatty acids, phytosterols and fat-soluble vitamins. [source] EFFECT OF STORAGE CONDITIONS ON THE SENSORY QUALITY OF GROUND ARABICA COFFEEJOURNAL OF FOOD QUALITY, Issue 6 2006CAROLYN F. ROSS ABSTRACT The objective of this study was to determine how long ground coffee beans could be stored at room and freezing temperatures before sensory changes could be detected, and to identify specific attribute changes associated with this storage. Ground beans were stored for 0 (fresh), 1, 2 and 3 weeks at room and freezing temperatures. Coffee was prepared from each of these treatments and difference testing was performed. Paired comparison tests were conducted on the fresh, 1- and 2-week-stored coffee grounds to examine the attributes of coffee aroma, flavor, bitterness and overall preference. At room temperature storage, results indicated significant (P < 0.05) differences in the coffee prepared from fresh versus the 2-week-stored ground beans. Coffee made from freshly ground beans had a stronger coffee aroma, less bitterness and was more preferred compared with the beans stored for 1 or 2 weeks (P < 0.05). At freezer storage, differences were detected between coffee prepared from coffee grounds stored for 1 or 2 weeks. Coffee prepared from grounds stored for 2 weeks had a stronger coffee aroma and was more bitter compared with the other storage times (P < 0.05). [source] POSTHARVEST CHANGES IN FRESH SWISS CHARD (Beta vulgaris, type cycla) UNDER DIFFERENT STORAGE CONDITIONSJOURNAL OF FOOD QUALITY, Issue 2 2000SARA INÉS ROURA ABSTRACT The effects of storage temperature and relative humidity on the quality of Swiss chard (Beta vulgaris, type cycla) were investigated. Quality was assessed through determinations of water content, weight loss, chlorophyll content, pH, titratable acidity, soluble solids content and sensory evaluations. Storage conditions were 4 and 18C and 43, 86 and 98% relative humidities (RH). The quality of chard leaves was unacceptable after three days of storage at 18C, independent of the RH. Chard leaves kept at 4C and 86 and 98% RH remained acceptable for 9 days. The dehydration suffered by samples kept at 4C and 43% RH turned them unacceptable after 4 days of storage. [source] Physicochemical Properties of Pacific Whiting Surimi as Affected by Various Freezing and Storage ConditionsJOURNAL OF FOOD SCIENCE, Issue 6 2002J. Reynolds ABSTRACT: Effects of various freezing methods of surimi on the biochemical and physical properties, were examined. Stress values increased up to 3 mo and then decreased. Strain values significantly decreased over time, except freeze-dried surimi stored at -18 °C. Yellowness (b*) of the freeze-dried surimi stored at 22 °C increased significantly during storage. In addition, salt-extractable proteins (SEP) decreased while dimethylamine (DMA) increased. Freeze-dried surimi showed the highest SEP and the lowest DMA values after 9 mo storage. Electrophoretic patterns did not show any apparent damages to the MHC until 6 mo. At 6 and 9 mo, development of proteins with smaller molecular weights was observed, indicating proteolytic degradation during frozen storage. [source] POSTHARVEST CHANGES IN FRESH SWISS CHARD (Beta vulgaris, type cycla) UNDER DIFFERENT STORAGE CONDITIONSJOURNAL OF FOOD QUALITY, Issue 2 2000SARA INÉS ROURA ABSTRACT The effects of storage temperature and relative humidity on the quality of Swiss chard (Beta vulgaris, type cycla) were investigated. Quality was assessed through determinations of water content, weight loss, chlorophyll content, pH, titratable acidity, soluble solids content and sensory evaluations. Storage conditions were 4 and 18C and 43, 86 and 98% relative humidities (RH). The quality of chard leaves was unacceptable after three days of storage at 18C, independent of the RH. Chard leaves kept at 4C and 86 and 98% RH remained acceptable for 9 days. The dehydration suffered by samples kept at 4C and 43% RH turned them unacceptable after 4 days of storage. [source] Sensory, chemical and microbiological quality parameters in sea bream (Sparus aurata) stored in ice or wrapped in cling film or in aluminium foil at 2 ± 1 °CINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 8 2007Fatih Özogul Abstract The effects of aluminium foil and cling film on sensory (raw and cooked), chemical and microbiological quality changes in cultured sea bream (Sparus aurata) stored at 2 ± 1 °C were investigated. The worst quality in terms of colour and odour was observed for sea bream wrapped in aluminium foil (WAF) and followed by fish wrapped in cling film (WCF). The shelf-life of sea bream was found to be 18 days for ice and 8 days for both fish wrapped in cling film and aluminium foil according to panellist perceptions. The total volatile basic nitrogen (TVB-N) value of sea bream stored in ice, wrapped in cling film and aluminium foil reached from initial value of 15.2 mg TVB-N/100 g to 28.6, 50.6 and 65.3 mg/100 g at 22, 15 and 15 days respectively. The highest growth of bacteria was found in sea bream for WAF, followed by WCF and lowest count was with ice storage condition. [source] Influence of storage regime prior to abrasion on surface topography of restorative materialsJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2003Cecilia Pedroso Turssi Abstract This investigation was carried out to evaluate the effect of storage conditions prior to brushing simulation on surface texture of restorative materials. One resin-modified glass ionomer (Fuji II LC Improved/GC Corp.), one polyacid-modified composite resin (Dyract AP/Denstply), one microfill composite (Durafill VS/Kulzer), and one hybrid (Filtek,Z250/3M) composite were tested. Forty-five standardized cylindrical specimens of each material were made and randomly divided into three groups according to their subsequent storage conditions: distilled deionized water, artificial saliva, or pH-cycling regime. After 24 h, the experimental units were finished and polished and the surface roughness was measured to obtain Ra baseline values (Bv). Samples were subjected to their assigned storage regime and brushed afterwards. By the end of 10 repetitions of this protocol, final surface roughness readings (Fv) were taken. The analysis of covariance (, = 0.05), considering the covariate Bv showed a significant interaction between restorative material and storage condition (pvalue = 0.0002). Tukey's test revealed that the pH-cycling model provided a significantly lower surface roughness for Fuji II LC and Dyract AP than did the other media. For both composites no significant difference among storage regimes was detected. Under a condition simulating dynamic variation in pH prior to abrasion, the resultant surface texture may be either smoothed down or unchanged, depending on the restorative material, when compared to the effect provided by artificial saliva and distilled deionized water. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 65B: 227,232, 2003 [source] PTR-TOF-MS and data-mining methods for rapid characterisation of agro-industrial samples: influence of milk storage conditions on the volatile compounds profile of Trentingrana cheese,JOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 9 2010Alessandra Fabris Abstract Proton transfer reaction-mass spectrometry (PTR-MS), a direct injection mass spectrometric technique based on an efficient implementation of chemical ionisation, allows for fast and high-sensitivity monitoring of volatile organic compounds (VOCs). The first implementations of PTR-MS, based on quadrupole mass analyzers (PTR-Quad-MS), provided only the nominal mass of the ions measured and thus little chemical information. To partially overcome these limitations and improve the analytical capability of this technique, the coupling of proton transfer reaction ionisation with a time-of-flight mass analyser has been recently realised and commercialised (PTR-TOF-MS). Here we discuss the very first application of this new instrument to agro-industrial problems and dairy science in particular. As a case study, we show here that the rapid PTR-TOF-MS fingerprinting coupled with data-mining methods can quickly verify whether the storage condition of the milk affects the final quality of cheese and we provide relevant examples of better compound identification in comparison with the previous PTR-MS implementations. In particular, ,Trentingrana' cheese produced by four different procedures for milk storage are compared both in the case of winter and summer production. It is indeed possible to set classification models with low prediction errors and to identify the chemical formula of the ion peaks used for classification, providing evidence of the role that this novel spectrometric technique can play for fundamental and applied agro-industrial themes. Copyright © 2010 John Wiley & Sons, Ltd. [source] EFFECT OF MINERAL FORTIFICATION ON RHEOLOGICAL PROPERTIES OF WHOLE WHEAT FLOURJOURNAL OF TEXTURE STUDIES, Issue 1 2009SAEED AKHTAR ABSTRACT This study was aimed to evaluate the rheological changes that take place in the dough as a result of addition of elemental iron, ferric sodium ethylenediaminetetraacetate, zinc sulphate and zinc oxide in various combinations to whole wheat flour (WWF), packaged in polypropylene woven bags and tin boxes and stored for a period of 60 days under ambient and controlled conditions of temperature and relative humidity. Water absorption (WA) capacity, dough development time (DDT) and dough stability time (DS) of the fortified WWF were measured by farinographic method, and peak viscosity was assessed by viscographic analyses. WA capacity and DDT of flours increased during storage. Fortification significantly (P < 0.05) affected WA, DDT, DS and viscographic characteristics of the flours. Packaging materials (P < 0.05) influenced WA, DDT and DS, while storage condition had only affected viscographic properties of the flours. PRACTICAL APPLICATIONS The success of any fortification program depends on the stability of micronutrients and food to which they are added. Exposure of the fortificants to any of the physical and chemical factors including heat, moisture, air, or light and acid or alkaline environments during food processing, packaging, distribution or storage affects their stability. The rheological properties of dough made from fortified flours determine the quality of the fortified end product. Changes in rheological properties as a result of the incorporation of fortificants in the flour, its storage under variable conditions and length of time might have an effect on quality, cost and nutrition of the product. [source] An analysis of the persistence and potency of film-coated seed protectant as influenced by various storage parametersPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 7 2009Sherry Rachel Jacob Abstract BACKGROUND: An efficient delivery system for seed-protectant chemicals is needed in light of several disadvantages of conventional seed treatment methods. This study evaluates the efficacy of film-coat application in maintaining the persistence and potency of imidacloprid on Lycopersicon esculentum (L.) Mill. seeds after simultaneous storage under ambient and regulated environment in paper and aluminium packages. RESULTS: High-performance liquid chromatography (HPLC) revealed 0.135 mg kg,1 of herbage material to be the threshold value beyond which absolute control was obtained, and with film coating the latter was achieved even with half-dosage seed treatment, irrespective of the storage condition. The technique provided early protection to the crop and also nullified the deleterious effects of ambient storage on the persistence and potency of the pesticide. CONCLUSION: Film coating enabled superior pesticide dosage as well as higher biological efficacy to be achieved. Hence, in addition to being an ecofriendly alternative, the technique would be a more economically viable option for storage of treated seeds. Copyright © 2009 Society of Chemical Industry [source] CD203c-based basophil activation test in allergy diagnosis: Characteristics and differences to CD63 upregulation,CYTOMETRY, Issue 5 2010Eva M. Sturm Abstract Background: The basophil activation test (BAT) based on CD203c upregulation has been validated as a reliable tool for the diagnosis of IgE-mediated allergies. Nevertheless, CD203c-based BAT is hardly comparable with that of CD63-based tests, as the mechanisms of CD203c versus CD63 induction differ considerably. The aim of the present study was to identify potent influencing factors of the CD203c-based BAT and to emphasize differences between CD63 and CD203c detection. Methods: CD203c-based BAT was determined in 82 healthy controls and in 79 allergic patients. The effects of interleukin (IL)-3 and degranulation enhancing substances were investigated and compared with CD63 upregulation. Furthermore, the influence of different storage conditions and incubation times was evaluated and the impact of antiallergic drugs on the test results was assessed. Results: CD203c and CD63 expression was rapidly upregulated reaching a maximum after 20,30 min. Basophil CD203c upregulation assayed after storage times up to 48 h declined already after 4 h. IL-3 treatment increased CD203c and CD63 baseline levels and decreased basophil CD203c responses in a dose-dependent manner. In contrast, cytochalasin B and latrunculin B did not affect CD203c responses but decreased CD63-based BAT. Finally, therapeutic concentrations of dimetindene and desloratadine did not affect CD203c upregulation. Conclusion: CD203c-based basophil activation test should be performed preferentially within 4 h after taking the blood samples. Priming and degranulation-enhancing factors are not required for CD203c-based BAT. In contrast to skin testing, CD203c-based BAT can be performed in patients undergoing antiallergic treatment. © 2010 International Clinical Cytometry Society [source] Effect of storage media on human periodontal ligament cell apoptosisDENTAL TRAUMATOLOGY, Issue 1 2008Mónica M. Chamorro However, the mechanisms by which different storage conditions alter the functional status of PDL cells have not been determined. The purpose of the present study was to investigate, in vitro, the level of programed cell death or apoptosis in a population of PDL cells following storage under different conditions. Primary human PDL cells were plated into 24-well-culture plates and allowed to attach for 24 h. Cells were then exposed for 1 h to milk, Hank's balanced salt solution (HBSS), Soft Wear contact lens solution or Gatorade at room temperature or on ice. Culture medium was used as a negative control. Apoptosis was evaluated at 24, 48, and 72 h after treatment on quadruplicate samples by using the ST 160 ApopTag Fluorescein Direct In Situ Detection Kit. The total number of cells and the total number of apoptotic cells were counted. The results indicated that at 24 and 72 h, PDL treated with Gatorade and the contact lens solution displayed the highest percentages of apoptotic cells when compared with the other treatment groups at room temperature. Overall, cells treated on ice showed significantly lower levels of apoptosis when compared with treatments at room temperature. In conclusion, the results indicated that apoptosis plays a major role in cell death in cells treated with Gatorade and contact lens solutions in comparison to other storage solutions and that storage on ice can inhibit programed cell death. [source] Spectroelectrochemical Sensing Based on Multimode Selectivity Simultaneously Achievable in a Single Device.ELECTROANALYSIS, Issue 5 2007Abstract Quaternized poly(4-vinylpyridine) (QPVP) has been incorporated as an anion exchanger into sol-gel derived silica films for use in a spectroelectrochemical sensor. The preparation, characteristics and performance of these films are described. The films, which are spin-coated onto the surface of a planar optically transparent electrode, are optically transparent and uniform. Scanning electron microscopy and spectroscopic ellipsometry have been used to examine film structure, thickness and optical properties. These films have been shown both spectroscopically and electrochemically to preconcentrate ferrocyanide, a model analyte for the sensor. The films can be regenerated for multiple measurements by exposure to 1,M KNO3. The effects of polymer molecular weight and storage conditions on film performance are described. The overall response of this film is comparable to the poly(dimethyldiallylammonium chloride)-silica films previously used for this sensor. [source] Physical-chemical characteristics and oxidative stability of oil obtained from lyophilized raspberry seedEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 11 2009Aleksandra, urovi Abstract Fresh raspberry (Rubus idaeus), cultivar Willamette, was freeze-dried (lyophilization). A byproduct of lyophilization is "fine dust" of raspberry consisting of finely ground raspberry fruit body and seed. The seeds were separated. The seed oil was isolated and its physical and chemical characteristics were determined. Parameters that characterize the seed and quality of the oil were examined, including fatty acid composition, oxidative stability under different storage conditions, and radical-scavenging activity. The fatty acid composition was determined by GC/FID and the contents of the dominant fatty acids were found as: oleic 16.92%, linoleic 54.95%, and ,-linolenic acid 23.97%. The oxidative stability of the oil was poor. The induction period by Rancimat test at 100,°C was 5.2,h. The radical-scavenging activity is similar to that of resveratrol [1,3-benzenediol 5-(1E -2-4-hydroxy-phenyl-ethyl)]. Although this product is used in the candy industry, it would be far more useful if raspberry oil of satisfactory quality could be extracted. This paper demonstrates that sifted lyophilized seeds can be used for the extraction of oils. This process allows for maximal usage of the byproducts, reduces losses and it increases the development of new products. [source] Lipid damage during frozen storage of Gadiform species captured in different seasonsEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 6 2007Santiago P. Aubourg Abstract Quality loss of two gadiform fish species (blue whiting, Micromesistius poutassou; hake, Merluccius merluccius) during frozen storage (,30 and ,10,°C; up to 12,months) was studied. For this, hydrolytic (formation of free fatty acids, FFA) and oxidative (conjugated dienes, peroxide and interaction compound formation) lipid damage were analysed. For both species, individual fishes captured in two different trials (May and November) were considered. Increasing (p,<0.05) lipid hydrolysis and oxidation (peroxide and interaction compound formation) were observed for all kinds of samples throughout the frozen storage. Interaction compound detection by fluorescence analysis showed the best correlation values with storage time. Some higher (p,<0.05) hydrolysis development could be observed in hake captured in May than in its counterpart from the November trial, while frozen blue whiting did not provide definite differences for FFA formation between both trials. Concerning peroxide formation, higher (p,<0.05) values were obtained for individual blue whiting and hake captured in November when compared to their corresponding May fish for both frozen storage conditions. Interaction compound formation was also found to be higher (p,<0.05) for November hake fish than for its counterpart captured in May, while blue whiting did not provide definite differences between trials. [source] The effect of ageing on the elastic modulus and degree of conversion of two multistep adhesive systemsEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 3 2010Giulio Marchesi Marchesi G, Navarra CO, Cadenaro M, Carrilho MR, Codan B, Sergo V, Di Lenarda R, Breschi L. The effect of ageing on the elastic modulus and degree of conversion of two multistep adhesive systems. Eur J Oral Sci 2010; 118: 304,310. © 2010 The Authors. Journal compilation © 2010 Eur J Oral Sci During the curing reaction, the monomers of dentine bonding systems should cross-link sufficiently to strengthen an adhesive so that it is clinically reliable. This study evaluated how different storage conditions (air vs. water storage) affect the elastic modulus (E-modulus) and degree of conversion (DC) of a three-step etch-and-rinse adhesive and a two-step self-etch adhesive. The biaxial flexural test and Raman microscopy were performed on resin disks made from the bonding agents Adper Scotchbond Multi-Purpose (SBMP; 3M ESPE) and Clearfil Protect Bond (CPB; Kuraray). The measurements were repeated after storage in either air or water for 15 and 30 min and for 1, 24, and 72 h. At time 0, the E-modulus was not affected by the adhesive system, whilst the degree of cure of CPB was higher than that of SBMP. Air storage increased the E-modulus at each ageing interval. Storage in water increased the E-modulus until it reached a maximum at 24 h, after which it decreased significantly at 72 h. No linear correlation between the percentage DC and E-modulus of the two adhesives was found when stored in water. The results of this study indicate that the mechanical properties and polymerization kinetics of SBMP and CPB are affected by storage time and medium. [source] Wettability alteration of caprock minerals by carbon dioxideGEOFLUIDS (ELECTRONIC), Issue 2 2007P. CHIQUET Abstract One of the critical factors that control the efficiency of CO2 geological storage process in aquifers and hydrocarbon reservoirs is the capillary-sealing potential of the caprock. This potential can be expressed in terms of the maximum reservoir overpressure that the brine-saturated caprock can sustain, i.e. of the CO2 capillary entry pressure. It is controlled by the brine/CO2 interfacial tension, the water-wettability of caprock minerals, and the pore size distribution within the caprock. By means of contact angle measurements, experimental evidence was obtained showing that the water-wettability of mica and quartz is altered in the presence of CO2 under pressures typical of geological storage conditions. The alteration is more pronounced in the case of mica. Both minerals are representative of shaly caprocks and are strongly water-wet in the presence of hydrocarbons. A careful analysis of the available literature data on breakthrough pressure measurements in caprock samples confirms the existence of a wettability alteration by dense CO2, both in shaly and in evaporitic caprocks. The consequences of this effect on the maximum CO2 storage pressure and on CO2 storage capacity in the underground reservoir are discussed. For hydrocarbon reservoirs that were initially close to capillary leakage, the maximum allowable CO2 storage pressure is only a fraction of the initial reservoir pressure. [source] A Numerical Model and Spreadsheet Interface for Pumping Test AnalysisGROUND WATER, Issue 4 2001Gary S. Johnson Curve-matching techniques have been the standard method of aquifer test analysis for several decades. A variety of techniques provide the capability of evaluating test data from confined, unconfined, leaky aquitard, and other conditions. Each technique, however, is accompanied by a set of assumptions, and evaluation of a combination of conditions can be complicated or impossible due to intractable mathematics or nonuniqueness of the solution. Numerical modeling of pumping tests provides two major advantages: (1) the user can choose which properties to calibrate and what assumptions to make; and (2) in the calibration process the user is gaining insights into the conceptual model of the flow system and uncertainties in the analysis. Routine numerical modeling of pumping tests is now practical due to computer hardware and software advances of the last decade. The RADFLOW model and spreadsheet interface presented in this paper is an easy-to-use numerical model for estimation of aquifer properties from pumping test data. Layered conceptual models and their properties are evaluated in a trial-and-error estimation procedure. The RADFLOW model can treat most combinations of confined, unconfined, leaky aquitard, partial penetration, and borehole storage conditions. RADFLOW is especially useful in stratified aquifer systems with no identifiable lateral boundaries. It has been verified to several analytical solutions and has been applied in the Snake River Plain Aquifer to develop and test conceptual models and provide estimates of aquifer properties. Because the model assumes axially symmetrical flow, it is limited to representing multiple aquifer layers that are laterally continuous. [source] Optimization of storage conditions for diluted working solutions of porcine factor VIII and performance of the Bethesda assay for the determination of antiporcine FVIII inhibitor titresHAEMOPHILIA, Issue 1 2003R. Winikoff Summary. The use of porcine factor VIII (FVIII) (Hyate:C, Ipsen) has proven to be very successful in treating patients with FVIII inhibitors. The best way to predict the usefulness of porcine FVIII therapy, and/or to estimate the appropriate treatment dose in a given patient, is to measure the patient inhibitor titre against porcine FVIII with the Bethesda assay, using porcine FVIII as the source of FVIII in the assay. The goals of the present study were to (1) find the optimal storage temperature, diluent and concentration for a working solution of porcine FVIII to be used as the source of FVIII for the porcine Bethesda assay, (2) assess the reliability of the labelled FVIII units in the preparation of such working solutions of porcine FVIII and (3) compare the inhibitor titres determined by the Bethesda assay using both porcine and human standard reference curves for measuring residual FVIII. The results of the present study demonstrate that a ready-to-use working solution of 1 U mL,1 of Hyate:C diluted in human FVIII deficient plasma, either containing or deficient in von Willebrand factor antigen, is stable for up to 12 months, at ,20 °C. The preparation of the 1 U mL,1 working solution could be reliably calculated based on the units indicated on the vial label. Finally, using the human standard curve yields similar results to using the porcine standard curve for measuring any titre of allo- or auto-antibody against FVIII in the Bethesda assay, using Hyate:C as the source of FVIII. These findings are of practical value when performing a porcine FVIII-based Bethesda assay. [source] Evaluation of the use of dried spots and of different storage conditions of plasma for HIV-1 RNA quantificationHIV MEDICINE, Issue 6 2007B Amellal Objectives The aim of the study was to evaluate the use of dried plasma spots to determine HIV-1 RNA viral loads. Methods The viral loads of 30 liquid plasma samples were compared with those of corresponding dried plasma spots on filter paper (DPS-FP) and in tubes (DPS-T), both of which were left for 7 days at 22°C. Also, 10 liquid plasma samples with detectable viral load were stored at 4, 22 or 37°C for 7 days and five further liquid plasma samples were air-dried for up to 54 h to assess the effects of temperature and the drying step on HIV-1 viral load. Results The viral loads of the 30 liquid plasma samples correlated significantly with those of the paired dried spots DPS-FP and DPS-T, but with median losses of 0.64 and 0.69 log10 HIV-1 RNA copies/mL, respectively, and a limit of detection of 3 log10 copies/mL. The 10 liquid plasma samples stored for 1 week at 37°C showed a weaker correlation and had a significantly reduced median viral load (,0.92 log10; P=0.005) when compared with the viral load of the matched plasma stored at ,80°C. Most of the loss happened during the drying step. Conclusions Reliable measurement of HIV-1 RNA viral load requires good plasma storage conditions. HIV RNA stability was affected by desiccation and 1 week of storage at 37°C. However, our findings suggest that liquid plasma can be kept at 4 or 22°C for a week with no effect on viral load. [source] Storage dynamics and streamflow in a catchment with a variable contributing areaHYDROLOGICAL PROCESSES, Issue 16 2010C. Spence Abstract Storage heterogeneity effects on runoff generation have been well documented at the hillslope or plot scale. However, diversity across catchments can increase the range of storage conditions. Upscaling the influence of small-scale storage on streamflow across the usually more heterogeneous environment of the catchment has been difficult. The objective of this study was to observe the distribution of storage in a heterogeneous catchment and evaluate its significance and potential influence on streamflow. The study was conducted in the subarctic Canadian Shield: a region with extensive bedrock outcrops, shallow predominantly organic soils, discontinuous permafrost and numerous water bodies. Even when summer runoff was generated from bedrock hillslopes with small storage capacities, intermediary locations with large storage capacities, particularly headwater lakes, prevented water from transmitting to higher order streams. The topographic bounds of the basin thus constituted the maximum potential contributing area to streamflow and rarely the actual area. Topographic basin storage had little relation to basin streamflow, but hydrologically connected storage exhibited a strong hysteretic relationship with streamflow. This relationship defines the form of catchment function such that the basin can be defined by a series of storing and contributing curves comparable with the wetting and drying curves used in relating tension and hydraulic conductivity to water content in unsaturated soils. These curves may prove useful for catchment classification and elucidating predominant hydrological processes. Copyright © 2009 John Wiley & Sons, Ltd and Her Majesty the Queen in right of Canada. [source] Use of real-time FT-IR monitoring of a pharmaceutical compound under stress atmospheric conditions to characterize its solid-state degradation kineticsINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 1 2010Peter J. Skrdla The use of online FT-IR is described for investigating the degradation kinetics of the solid amorphous pharmaceutical compound, fosaprepitant dimeglumine (FD), under stress storage conditions (i.e., high temperature, T, and humidity, % RH). It is found that under conditions of elevated T and % RH, the kinetics are denucleation rate limited for the deliquescence of the amorphous FD solid, based on the high quality fits obtained to the authors' dispersive kinetic model for that mechanism. At elevated T and low % RH, it is found that a classical, first-order hydrolysis mechanism for the degradation of FD (which forms crystalline aprepitant, AP) significantly contributes to the overall conversion rate. That mechanism is similar to the one observed previously for the solution-phase hydrolysis of FD. Appropriate kinetic models are proposed for the FD-to-AP conversion under all of the experimental conditions investigated in this work. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 42: 25,36, 2010 [source] A very promising new glucolipidic surfactant: LipowheatTMINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 6 2005A. Djedour Synopsis LipowheatTM is an entirely biodegradable 100% natural active ingredient, extracted from non-transgenic wheat. Thanks to its very interesting properties, it can integrate the composition of most cosmetic and pharmaceutical products. The aim of this work was first to realize a large range of stable simple or multiple emulsions, in order to determine and evaluate the ability of a new glucolipidic surfactant LipowheatTM to form and stabilize emulsions. The rheological properties of these emulsions were tested during a 30-day storage period at three different storage conditions (cold, room temperature and at 40°C). In addition to dynamic and static rheological tests, droplet size distribution of the cream was also determined. Furthermore, a stable simple emulsion was selected to realize percutaneous absorption and evaluate the properties of LipowheatTM. Résumé Ce travail a pour objectif de mettre à jour et d'évaluer les propriètés émulsionnantes d'un nouveau tensioactif de nature glucolipidique, connu jusqu'alors pour ses propriétés actives en cosmétologie: le LipowheatTM. Cette étude comporte plusieurs parties distinctes: 1) Formulation d'émulsions simples L/H et/ou H/L et multiples H/L/H stabilisèes par du LipowheatTM, avec des huiles variant par leur origine (naturelle ou synthétique) ainsi que par leur polarité. 2) Caractérisation rhéologique, granulométrique, et conductimétrique de ces émulsions après les avoir soumises pendant 30 jours à des conditions de vieillissement accéléré (conservation à température ambiante, à +4°C et +40°C) et ce, afin d'en retenir les plus stables pour la suite de l'étude. 3) Enfin, dans une dernière phase, les propriètés de ces crèmes dans le domaine de la libération dermopharmaceutique seront évaluées lors d'études in vitro. [source] The effect of long-term frozen storage on the quality of frozen and thawed mashed potatoes with added cryoprotectant mixturesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 7 2009Cristina Fernández Summary Cryoprotectant mixtures were added to frozen/thawed (F/T) mashed potatoes in the form of amidated low-methoxyl (ALM) pectin and xanthan gum (XG), kappa-carrageenan (,-C) and XG and sodium caseinate (SC) and XG, and the effect of frozen storage was examined. F/T mashed potatoes without added biopolymers had higher storage modulus G, after freezing and frozen storage, associated with sponge formation due to amylose retrogradation. Oscillatory measurements indicated weakening of the structure of mashed potatoes without biopolymers and with added ,-C/XG and SC/XG mixtures at the end of storage due to ice recrystallisation, whereas the structure of samples with added ALM/XG mixtures was reinforced by increasing time in storage. Mashed potatoes with added mixtures exhibited water-holding capacity for 1 year. Samples with added ,-C/XG mixtures were more structured, although when both ,-C/XG and SC/XG mixtures were included in mashed potato, very acceptable sensory quality was maintained in usual frozen storage conditions. [source] The use of packaging techniques to maintain freshness in fresh-cut fruits and vegetables: a reviewINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 5 2009Mª Alejandra Rojas-Graü Summary Browning and other discolourations, softening, surface dehydration, water loss, translucency, off-flavour and off-odour development, as well as microbial spoilage are some of the most frequent causes of quality loss in fresh-cut products. Nowadays, the use of innovative modified atmospheres and edible coatings stands out among other techniques in the struggle for maintaining freshness and safety of fresh-cut fruits and vegetables. A few studies have demonstrated the effectiveness of these techniques when applied to different fresh-cut commodities. However, treatment and storage conditions for fresh-cut fruits are still being largely explored to better keep their fresh-like quality attributes. This review discusses the recent advances in the use of innovative modified atmosphere packaging (MAP) systems to maintain freshness of fresh-cut fruits and vegetables. Furthermore, special attention is devoted to the development of coatings that can be used as a complement or alternative to MAP. [source] The effects of soluble gas stabilisation on the quality of packed sardine fillets (Sardina pilchardus) stored in air, VP and MAPINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 11 2008Rogério Mendes Summary Sardine (Sardina pilchardus) is a species that for its abundance assumes great importance in the Portuguese fishing sector. In order to contribute for a better utilisation of this species, the aim of this study was to investigate the effect of the pre-treatment with soluble gas stabilisation (SGS) (100% CO2 at 2 bar, during 15 and 30 min) on the quality and shelf-life of sardine fillets, packed in air (AP), vacuum (VP) and modified atmosphere (MAP: 5% O2/35% CO2/60% N2). During the chilled storage, the quality changes were evaluated by sensory evaluation, chemical and microbiological analysis. The total volatile basic nitrogen content remained almost constant, between 16 and 19 mg N/100 g muscle, during the storage period, for all samples. The TBARs values increased with storage time, for all batches and storage conditions. The application of SGS treatment to sardine fillets, resulted in a bacteriostatic effect, contributing to the improvement of the microbiological quality of fillets. Considering a sensory criteria, the shelf-life of SGS pre-treated sardine fillets was found to be 5 days in AP and MAP while in VP-treated fillets a shelf-life of 8 days was reported. At sensory rejection, sardine fillets presented a K -value of 30% in AP and MAP batches and 40% in VP batch. [source] Influence of temperature and time before centrifugation of specimens for routine coagulation testingINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 4 2009G. L. SALVAGNO Summary The accurate standardization of the preanalytical phase is of pivotal importance for achieving reliable results of coagulation tests. Because information on the suitable storage conditions for coagulation testing is controversial, we aimed at investigating the sample stability with regard to the temperature and time before centrifugation. The activated partial thromboplastin time (aPTT), prothrombin time (PT), fibrinogen and D-dimer were assayed in specimens collected from 26 consecutive patients on antivitamin K therapy on the ACL TOP analyzer. Three primary 3.6-ml siliconized evacuated tubes containing 0.109 mol/l buffered trisodium citrate were sequentially collected from each patient. These three tubes were mixed, pooled and divided into seven identical aliquots. The first aliquot was immediately centrifuged according to the standard protocol [1500 g for 15 min at room temperature (RT)] and analyzed. The other aliquots were left for 3, 6 and 24 h, respectively, at RT or 4 °C, and then centrifuged and analyzed. Test results were compared with those obtained on the reference specimen. Statistically significant prolongations were observed for aPTT in all the samples. Such differences exceeded the analytical quality specifications for desirable bias in the samples stored for 24 h. A significant reduction, yet comprised within the desirable bias, was observed for PT and fibrinogen in uncentrifuged specimens stored at RT for 3 and 6 h. No significant biases could be recorded in D-dimer. In conclusion, a 6-h storage of uncentrifuged specimens at either RT or 4 °C may still be suitable to achieve results of routine coagulation testing comprised within the analytical quality specifications for desirable bias. [source] Structure and Functioning of the "Egg Bank" of a Fairy Shrimp in a Temporary Pool: Chirocephalus ruffoi from Pollino National Park (Southern Italy) as a Case StudyINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 1 2004Graziella Mura Abstract To investigate their distribution and total numbers, resting eggs of the anostracan Chirocephalus ruffoi were collected from the bed of a temporary pool in southern Italy. Samples were taken at 0.5 m intervals along six transects oriented at 30° from each other, by means of a cylindrical core sampler. The horizontal distribution of intact resting eggs was extremely patchy, with cyst number per core ranging from 191 to 1,400 (CV = 32.7%), corresponding to a mean of between 0.8 and 4.3 cysts cm,3. Differences observed were related to core position and transect orientation, total cyst numbers being markedly higher in the leeward area of the pool compared to the windward area. Marked variation was also evident in vertical distribution, a significant, though weak correlation was recorded between egg density and sediment depth. Cyst-bank size (± 95% confidence limits) of the pool bed, estimated from the mean cyst number cm,3 obtained for the 6 transects, ranged between 1.0 × 108 and 1.3 × 108 cysts. Hatching in the laboratory was very erratic. Despite significant differences in hatching, the observed variation was unrelated to most of the variables considered (position within sections, cores and transects, pre-incubation treatment) and was explained only by initial sediment conditions (moist/dry). In none of the experimental conditions tested was synchronous hatching obtained. Possible causal factors (mixing of the bottom sediments by cattle, egg age, storage conditions, differential exposure to environmental cues as well as variability in hatching response even at clutch level) are discussed. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Effects of storage aging on the cure kinetics of bismaleimide prepregsADVANCES IN POLYMER TECHNOLOGY, Issue 4 2005M. Frigione The effects of room temperature aging on the subsequent polymerization kinetics of a bismaleimide (BMI) matrix prepreg, for high performance composites, have been characterized by different time and storage conditions. The study has focused on the stability of BMI matrix carbon fiber prepregs, when exposed to controlled environmental conditions before being used in composite manufacturing. The effects of aging on glass transition temperature, reactivity, and processability have been investigated by calorimetry through dynamic, isothermal, and cure-simulating tests. A theoretical kinetic model for epoxy matrix prepregs, developed in previous studies, has been applied to the polymerization of both aged and unaged BMI matrix. The model is able to satisfactorily describe the effect of processing variables such as temperature and degree of reaction during the curing of the composite under different conditions (curing temperature and heating rate). The effects of diffusion-controlled phenomena on the reaction kinetics, associated with changes in glass transition temperature as a function of the degree of polymerization and cross-linking, have been taken into account in the formulation of an nth-order kinetic model. © 2005 Wiley Periodicals, Inc. Adv Polym Techn 24: 253,265, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20048 [source] The influence of storing beef aerobically or in vacuum packs on the shelf life of minceJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2010K.M. Crowley Abstract Aims:, To investigate the influence of aerobic or vacuum pack storage of beef trimmings on the microbiology, colour and odour of subsequently produced mince. Methods and Results:, Trimmings stored aerobically for 7 or 10 days and in vacuum packs for 7, 10, 14 or 22 days at 0 or 5°C were minced, stored aerobically at 0 or 5°C for up to 7 days and examined daily to determine Total viable, Pseudomonas, Lactic acid bacteria, Brochothrix thermosphacta, and Enterobacteriaceae counts, colour and odour. Mincing reduced counts, particularly of Pseudomonas, B. thermosphacta and Enterobacteriaceae, probably because of the action free radicals released from muscle and bacterial cells. Storage of vacuum-packed trimmings for 22 days resulted in improved mince colour and inhibition of the growth of Pseudomonas. Conclusions:, The shelf life of mince from trimmings is directly influenced by the trimmings storage conditions, and longer-term vacuum storage of trimmings produced improvements in mince quality. Significance and Impact of the Study:, There appears to be no scientific rationale for limiting the storage of vacuum packaging beef trimmings to 15 days, prior to mince production, as stated in EU 835/2004. This study identifies advantages in storing trimmings in vacuum packs for at least 21 days prior to mincing, in terms of improved mince quality. [source] | |||||||||||||||||||||||||