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Short Time (short + time)
Kinds of Short Time Terms modified by Short Time Selected AbstractsEFFECT OF HOT WATER IMMERSION ON PEEL COLOR OF PEARS AND ON WHITE ROT CAUSED BY BOTRYOSPHAERIA BERENGERIANAJOURNAL OF FOOD QUALITY, Issue 5 2003MUHAMMAD IMRAN AL-HAQ After HWI at 40, 45, 48, 50, 52 and 54C for varying immersion periods, the pears were held at 20C, , 90% RH (simulated retail conditions). The peel color (L*, a*, b*) was determined before and after HWI treatment. The dominant role of L* suggested that peel darkening was the major factor in color change of the HWI treated pears. The L* value of 54 was judged as the border line for acceptability and less than 51 resulted in browning. Similarly the critical points for a*, b*, chroma, hue and ,E* were found to be ,6, 34, 35, 100, and 8, respectively. Disease incidence recorded 7 days after treatment revealed that High Temperature Short Time (HTST) treatment of 54C for 3 min reduced incidence about 85% with good retention of color. Both temperature and immersion period are to be carefully selected to prolong shelf-life and retain the peel color quality of ,La-France'pears. [source] High-pressure granulites: formation, recovery of peak conditions and implications for tectonicsJOURNAL OF METAMORPHIC GEOLOGY, Issue 1 2003P. J. O'Brien Abstract High-pressure granulites are characterised by the key associations garnet-clinopyroxene-plagioclase-quartz (in basic rocks) and kyanite-K-feldspar (metapelites and felsic rocks) and are typically orthopyroxene-free in both basic and felsic bulk compositions. In regional metamorphic areas, two essential varieties exist: a high- to ultrahigh-temperature group and a group representing overprinted eclogites. The high- to ultrahigh-temperature type formerly contained high-temperature ternary feldspar (now mesoperthite) coexisting with kyanite, is associated with garnet peridotites, and formed at conditions above 900 °C and 1.5 GPa. Clinopyroxene in subordinate basic rocks is Al-rich and textural evidence points to a high-pressure,high-temperature melting history. The second variety contains symplectite-like or poikilitic clinopyroxene-plagioclase intergrowths indicating former plagioclase-free, i.e. eclogite facies assemblages. This type of rock formed at conditions straddling the high-pressure amphibolite/high-pressure granulite field at around 700,850 °C, 1.0,1.4 GPa. Importantly, in the majority of high-pressure granulites, orthopyroxene is secondary and is a product of reactions at pressures lower than the peak recorded pressure. In contrast to low- and medium-pressure granulites, which form at conditions attainable in the mid to lower levels of normal continental crust, high-pressure granulites (of nonxenolith origin) mostly represent rocks formed as a result of short-lived tectonic events that led to crustal thickening or subduction of the crust into the mantle. Short times at high-temperature conditions are reflected in the preservation of prograde zoning in garnet and pyroxene. High-pressure granulites of both regional types, although rare, are known from both old and young metamorphic terranes (e.g. c. 45 Ma, Namche Barwa, E Himalaya; 400,340 Ma, European Variscides; 1.8 Ga Hengshan, China; 1.9 Ga, Snowbird, Saskatchewan and 2.5 Ga Jianping, China). This spread of ages supports proposals suggesting that thermal and tectonic processes in the lithosphere have not changed significantly since at least the end of the Archean. [source] Towards virtualized desktop environmentCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 4 2010Xiaofei Liao Abstract Virtualization is being widely used now as an emerging trend. Rapid improvements in network bandwidth, ubiquitous security hazards and high total cost of ownership of personal computers have created a growing market for desktop virtualization. Much like server virtualization, virtualizing desktops involves separating the physical location of a client device from its logical interface. But, the performance and usability of some traditional desktop frameworks do not satisfy end-users. Other solutions, including WebOS, which needs to rebuild all daily-used applications into Client/Server mode, cannot be easily accepted by people in a short time. We present LVD, a system that combines the virtualization technology and inexpensive personal computers (PCs) to realize a lightweight virtual desktop system. Comparing to the previous desktop systems, LVD builds an integrated novel desktop environment, which can support the backup, mobility, suspending and resuming of per-user's working environment, and support synchronous using of incompatible applications on different platforms and achieves great saving in power consumption. We have implemented LVD in a cluster with Xen and compared its performance against widely used commercial approaches, including Microsoft RDP, Citrix MetaFrameXP and Sun Ray. Experimental results demonstrate that LVD is effective in performing the functions while imposing little overhead. Copyright © 2009 John Wiley & Sons, Ltd. [source] Exotic plant species invade diversity hot spots: the alien flora of northwestern KenyaECOGRAPHY, Issue 2 2000J. Stadler We analysed the distribution of native and alien plant species across 20 ecogeographic zones of northwestern Kenya. The source pool for the majority of aliens was Europe and America. Thus, the source pool has a biogeographic bias which explains the low proportion of aliens in the tropics: most species in the European or American source pool are not well adapted to tropical conditions. As expected, native and alien plant species showed an area effect. Correcting for this area effect. species rich zones showed a higher proportion of alien plant species in their flora. At the analysed scale, species richness of native plant communities does not increase the resistance to invasions and alien plant species invade diversity hotspots. Compared to the other ecogeographic zone, the urban area around Nairobi showed an increased richness in alien and native plant species. This is very similar to findings in Europe, although the history of urbanisation is much shorter in Kenya. The species turnover between zones (,-diversity) shows a similar pattern in native and alien plant species. Within a very short time scale the alien plant species mapped the biogeographic patterns of natives, although the geography of human activities influences the propagule pressure. [source] Using sensation seeking to target adolescents for substance use interventionsADDICTION, Issue 3 2010James D. Sargent ABSTRACT Aims This study examines the predictive validity of sensation seeking as a predictor of adolescent substance use, in order to optimize targeting for substance use prevention programs. Design Longitudinal study. Setting Random-digit dial telephone survey. Participants A total of 6522 US adolescents aged 10,14 years at baseline, resurveyed at 8-month intervals for three subsequent waves. Measurements Two outcomes were assessed,onset of binge drinking (more than five drinks in a short time) and established smoking (>100 cigarettes life-time). Sensation seeking level was assessed at baseline. Logistic regression was used to predict onset of substance use at any follow-up wave as a function of sensation seeking. The receiver operating characteristics curve was used to illustrate how well sensation seeking predicted substance use as a function of different cut-off points for defining high sensation seeking, and area under the receiver operating characteristics curve (AROC) was the metric of predictive validity. Findings Of 5834 participants with one or more follow-up assessments, 5634 reported no binge drinking and 5802 were not established smokers at baseline, of whom 717 (12.7% of 5634) reported binge drinking and 144 (2.5% of 5802) reported established smoking at one or more follow-up interviews. Sensation seeking predicted binge drinking moderately well [AROC = 0.71 (95% confidence interval 0.69, 0.73)] and was a significantly better predictor of established smoking onset [AROC = 0.80 (0.76, 0.83)]. For binge drinking, predictive validity was significantly lower in blacks; for established smoking it was significantly higher for Hispanics. Implications for two targeting interventions are discussed. Conclusions Sensation seeking works moderately well at identifying adolescents at risk for onset of binge drinking and established smoking. This study offers a guide for determining the appropriate targeting cut-off value, based on intervention efficacy, costs and risks. [source] Polyaniline Film Based Amperometric pH Sensor Using A Novel Electrochemical Measurement SystemELECTROANALYSIS, Issue 8 2009Wei Gao Abstract A polyaniline based amperometric pH sensor has been developed using a novel electrochemical measurement system. A polyaniline film (PANI) coated pencil graphite electrode (PGE) is connected in series between the working and counter electrodes of a potentiostat, and immersed in the solution together with a reference electrode. When an external potential is applied, the resulting current varies with the solution pH, which provides the basis for the amperoemtric pH sensor. Equations describing the measurement principle are presented. Based on pH dependent emeraldine salt,emeraldine base transition of PANI film, the pH sensor exhibits high stability, accuracy, selectivity, sensitivity and a short time. [source] A new method for fabrication of an integrated indium tin oxide electrode on electrophoresis microchips with amperometric detection and its application for determination of synephrine and hesperidin in pericarpium citri reticulataeELECTROPHORESIS, Issue 21 2006Wei Wang Abstract A new, simple, and fast method to integrate indium tin oxide electrode in an amperometric detection (AD) microchip is introduced. Without the help of photoresist and complicated apparatus, the microchip could be fabricated in most laboratories in a very short time by this method. The experiment indicated that the microchip was stable and had good reproducibility. On this microchip, a new method was established to separate and determine synephrine and hesperidin, which are the main electroactively bioactive ingredients of pericarpium citri reticulatae, by AD. Under the optimal conditions, the two compounds could be completely separated within 5.5,min and the detection limits were 0.13 and 0.57,,g/mL, respectively. The proposed method has been successfully used to determine synephrine and hesperidin in real pericarpium citri reticulatae sample, and the results show that the proposed method is sensitive, reliable, fast, and economical. [source] Influence of bacitracin on microbial functions in the gastrointestinal tract of horsesEQUINE VETERINARY JOURNAL, Issue 4 2000E. Collinder Summary This study investigated the influence of zinc bacitracin on the intestinal flora of horses. The functionally active intestinal flora was examined in 6 horses during treatment with zinc bacitracin. Utilising gas chromatography, spectrophotometry, gel electrophoresis and paper chromatography, samples were analysed on biochemical markers reflecting the action of parts of the intestinal flora. The following 5 flora-related functions were studied in faecal samples and intestinal samples from different sections of the hindgut: conversion of cholesterol to coprostanol and of bilirubin to urobilinogens, degradation of mucin and of ,-aspartylglycine and inactivation of tryptic activity. Conversion to coprostanol, conversion to urobilinogens and degradation of mucin were affected by treatment of zinc bacitracin and conversion to coprostanol was most sensitive. All functions were normalised in a short time, in contrast to man and rats. Differences in environmental exposures are probably the reason for a more rapid normalisation of the intestinal flora functions in horses. [source] CD2+/CD14+ monocytes rapidly differentiate into CD83+ dendritic cellsEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 2 2003Di Pucchio, Tiziana Abstract Since denditric cells (DC) represent the main players linking innate and adaptive immunity, their prompt generation from blood cells would be instrumental for an efficient immune response to infections. Consistent with this, CD2+ monocytes were found to express the DC maturation marker CD83, along with acquisition of high antigen-presenting activity, after a surprisingly short time in culture. This rapid process is associated with expression of IFN-,/, genes and secretion of low levels of pro-inflammatory cytokines. Exposure of monocytes to IFN-,, but not to IL-4, induced persistence of CD2+/CD83+ cells, which were fully competent in stimulating primary responses by naive T cells. These results unravel the natural pathway by which infection-induced signals rapidly transform pre-armed monocytes into active DC. [source] SEQUENTIAL RAPID ADAPTATION OF INDIGENOUS PARASITOID WASPS TO THE INVASIVE BUTTERFLY PIERIS BRASSICAEEVOLUTION, Issue 8 2007Shingo Tanaka The introduction of a new species can change the characteristics of other species within a community. These changes may affect discontiguous trophic levels via adjacent trophic levels. The invasion of an exotic host species may provide the opportunity to observe the dynamics of changing interspecific interactions among parasitoids belonging to different trophic levels. The exotic large white butterfly Pieris brassicae invaded Hokkaido Island, Japan, and quickly spread throughout the island. Prior to the invasion, the small white butterfly P. rapae was the host of the primary parasitoid Cotesia glomerata, on which both the larval hyperparasitoid Baryscapus galactopus and the pupal hyperparasitoid Trichomalopsis apanteroctena depended. At the time of the invasion, C. glomerata generally laid eggs exclusively in P. rapae. During the five years following the invasion, however, the clutch size of C. glomerata in P. rapae gradually decreased, whereas the clutch size in P. brassicae increased. The field results corresponded well with laboratory experiments showing an increase in the rate of parasitism in P. brassicae. The host expansion of C. glomerata provided the two hyperparasitoids with an opportunity to choose between alternative hosts, that is, C. glomerata within P. brassicae and C. glomerata within P. rapae. Indeed, the pupal hyperparasitoid T. apanteroctena shifted its preference gradually to C. glomerata in P. brassicae, whereas the larval hyperparasitoid B. galactopus maintained a preference for C. glomerata in P. rapae. These changes in host preference may result from differential suitability of the two host types. The larval hyperparasitoid preferred C. glomerata within P. rapae to C. glomerata within P. brassicae, presumably because P. brassicae larvae attacked aggressively, thereby hindering the parasitization, whereas the pupal hyperparasitoid could take advantage of the competition-free resource by shifting its host preference. Consequently, the invasion of P. brassicae has changed the host use of the primary parasitoid C. glomerata and the pupal hyperparasitoid T. apanteroctena within a very short time. [source] Expert system for nuclear power plant accident diagnosis using a fuzzy inference methodEXPERT SYSTEMS, Issue 4 2002rey Lee Huge and complex systems such as nuclear power generating stations are likely to cause the operators to make operational mistakes for a variety of inexplicable reasons and to produce ambiguous and complicated symptoms in the case of an emergency. Therefore, a safety protection system to assist the operators in making proper decisions within a limited time is required. In this paper, we develop a reliable and improved diagnosis system using the fuzzy inference method so that the system can classify accident symptoms and identify the most probable causes of accidents in order for appropriate actions to be taken to mitigate the consequences. In the computer simulation, the proposed system proved to be able to classify accident types within only 20,30 s. Therefore, the corresponding operation guidelines can be determined in a very short time to put the nuclear power plant in a safe state immediately after the accident. [source] The adaptive response of anaerobically grown Saccharomyces cerevisiae to hydrogen peroxide is mediated by the Yap1 and Skn7 transcription factorsFEMS YEAST RESEARCH, Issue 8 2008Anthony G. Beckhouse Abstract The molecular mechanisms involved in the ability of cells to adapt and respond to differing oxygen tensions are of great interest to the pharmaceutical, medical and fermentation industries. The transcriptional profiles reported in previous studies of cells grown under anaerobic, aerobic and dynamic growth conditions have shown significantly altered responses including induction of genes regulated by the oxidative stress transcription factor Yap1p when oxygen was present. The present study investigated the phenotypic changes that occur in cells when shifted from anaerobic to aerobic growth conditions and it was found through mutant analyses that the elevated activity of Yap1p during the shift was mediated by the phospholipid hydroperoxide-sensing protein encoded by GPX3. Cell viability and growth rate were unaffected even though anaerobically grown cells were found to be hypersensitive to low doses of the oxidative stress-inducing compound hydrogen peroxide (H2O2). Adaptation to H2O2 treatment was demonstrated to occur when anaerobically grown wild-type cells were aerated for a short time that was reliant on the Yap1p and Skn7p transcription factors. [source] Colonization of beech leaves by two endophytic fungi in northern JapanFOREST PATHOLOGY, Issue 2 2000N. Sahashi Summary Leaves of Japanese beech (Fagus crenata) were collected monthly during the vegetation period at five sites in the Tohoku district in Japan to isolate endophytic fungi. Leaves were also collected only once at two additional sites. Two endophytic fungi were dominant, a Discula species and a sterile mycelium. This result strongly suggests that these two fungi are generally associated with leaves of the Japanese beech at different sites. At most sites the isolation frequency of Discula sp. was greatest in June and gradually decreased from July to October whereas the isolation frequency of the sterile mycelium increased during the vegetation period and remained at a high isolation frequency in October. Spores of Discula sp. were released for a very short time in late May, just after the disappearance of the snow cover on the forest floor. These spores may be important for the infection of newly sprouting leaves. [source] Biogeochemical modelling of the rise in atmospheric oxygenGEOBIOLOGY, Issue 4 2006M. W. CLAIRE ABSTRACT Understanding the evolution of atmospheric molecular oxygen levels is a fundamental unsolved problem in Earth's history. We develop a quantitative biogeochemical model that simulates the Palaeoproterozoic transition of the Earth's atmosphere from a weakly reducing state to an O2 -rich state. The purpose is to gain an insight into factors that plausibly control the timing and rapidity of the oxic transition. The model uses a simplified atmospheric chemistry (parameterized from complex photochemical models) and evolving redox fluxes in the Earth system. We consider time-dependent fluxes that include organic carbon burial and associated oxygen production, reducing gases from metamorphic and volcanic sources, oxidative weathering, and the escape of hydrogen to space. We find that the oxic transition occurs in a geologically short time when the O2 -consuming flux of reducing gases falls below the flux of organic carbon burial that produces O2. A short timescale for the oxic transition is enhanced by a positive feedback due to decreasing destruction of O2 as stratospheric ozone forms, which is captured in our atmospheric chemistry parameterization. We show that one numerically self-consistent solution for the rise of O2 involves a decline in flux of reducing gases driven by irreversible secular oxidation of the crust caused by time-integrated hydrogen escape to space in the preoxic atmosphere, and that this is compatible with constraints from the geological record. In this model, the timing of the oxic transition is strongly affected by buffers of reduced materials, particularly iron, in the continental crust. An alternative version of the model, where greater fluxes of reduced hydrothermal cations from the Archean seafloor consume O2, produces a similar history of O2 and CH4. When climate and biosphere feedbacks are included in our model of the oxic transition, we find that multiple ,Snowball Earth' events are simulated under certain circumstances, as methane collapses and rises repeatedly before reaching a new steady-state. [source] Insights into biaxial extensional tectonics: an examplefrom the Sand,kl, Graben, West Anatolia, TurkeyGEOLOGICAL JOURNAL, Issue 1 2003Mustafa Cihan Abstract West Anatolia, together with the Aegean Sea and the easternmost part of Europe, is one of the best examples of continental extensional tectonics. It is a complex area bounded by the Aegean,Cyprus Arc to the south and the North Anatolian Fault Zone (NAFZ) to the north. Within this complex and enigmatic framework, the Sand,kl, Graben (10,km wide, 30,km long) has formed at the eastern continuation of the Western Anatolian extensional province at the north-northwestward edge of the Isparta Angle. Recent studies have suggested that the horst,graben structures in West Anatolia formed in two distinct extensional phases. According to this model the first phase of extension commenced in the Early,Middle Miocene and the last, which is accepted as the onset of neotectonic regime, in Early Pliocene. However, it is controversial whether two-phase extension was separated by a short period of erosion or compression during Late Miocene,Early Pliocene. Both field observations and kinematic analysis imply that the Sand,kl, Graben has existed since the Late Pliocene, with biaxial extension on its margins which does not necessarily indicate rotation of regional stress distribution in time. Although the graben formed later in the neotectonic period, the commencement of extension in the area could be Early Pliocene (c. 5,Ma) following a severe but short time of erosion at the end of Late Miocene. The onset of the extensional regime might be due to the initiation of westward motion of Anatolian Platelet along the NAFZ that could be triggered by the higher rate of subduction at the east Aegean,Cyprus Arc in the south of the Aegean Sea. Copyright © 2003 John Wiley & Sons, Ltd. [source] Impaired intercellular adhesion and immature adherens junctions in merlin-deficient human primary schwannoma cellsGLIA, Issue 5 2008C. Flaiz Abstract Schwannomas that occur spontaneously or in patients with neurofibromatosis Type 2, lack both alleles for the tumor suppressor and plasma membrane-cytoskeleton linker merlin. We have shown that human primary schwannoma cells display activation of the RhoGTPases Rac1 and Cdc42 which results in highly dynamic and ongoing protrusive activity like ruffling. Ruffling is an initial and temporally limited step in the formation of intercellular contacts like adherens junctions that are based on the cadherin-catenin system. We tested if there is a connection between Rac1-induced ongoing ruffling and the maintenance, stabilization and functionality of adherens junctions and if this is of relevance in human, merlin-deficient schwannoma cells. We show intense ongoing ruffling is not limited to membranes of single human primary schwannoma cells, but occurs also in membranes of contacting cells, even when confluent. Live cell imaging shows that newly formed contacts are released after a short time, suggesting disturbed formation or stabilization of adherens junctions. Morphology, high phospho-tyrosine levels and cortactin staining indicate that adherens junctions are immature in human primary schwannoma cells, whereas they display characteristics of mature adherens junctions in human primary Schwann cells. When merlin is reintroduced, human primary schwannoma cells show only initial ruffling in contacting cells and adherens junctions appear more mature. We therefore propose that ongoing Rac-induced ruffling causes immature adherens junctions and leads to impaired, nonfunctional intercellular adhesion in aggregation assays in merlin-deficient schwannoma cells that could be an explanation for increased proliferation rates due to loss of contact inhibition or tumor development in general. © 2008 Wiley-Liss, Inc. [source] A Mild and Efficient Method for N -Arylnucleobase Synthesis via the Cross-Coupling Reactions of Nucleobases with Arylboronic Acids Catalyzed by Simple Copper SaltsHELVETICA CHIMICA ACTA, Issue 6 2008Lan Tao Abstract A simple and efficient copper-salt catalyzed N -arylation of nucleobases is reported. In a mixed solvent of MeOH and H2O, the coupling products were obtained in moderate to excellent yields at room temperature within a short time. A variety of substituted N -aryl nucleobases can be prepared through this procedure. [source] Brief breath holding may confound functional magnetic resonance imaging studiesHUMAN BRAIN MAPPING, Issue 4 2005David F. Abbott Abstract We demonstrate that breath holding of short durations may confound functional magnetic resonance imaging (fMRI) studies. Some subjects may hold their breath for a short time during task performance, especially if the task is challenging. Breath holding may therefore need to be considered specifically when interpreting fMRI experiments. We studied the temporal and spatial characteristics of cerebral T2*-weighted signal during short periods of breath holding by seven individuals in a 3-tesla MR scanner. We demonstrate that breath-holds as short as 3 s can result in regions of significant cerebral activation. More interestingly, we show that focal activation remains present when the data is analysed in a number of different ways, including analyses that correct for motion and model the task epoch as if it were 10 times longer than the actual breath-hold length. These findings have potential relevance for many researchers carrying out fMRI studies. Hum. Brain Mapping 24:284,290, 2005. © 2005 Wiley-Liss, Inc. [source] GPSPA: a new adaptive algorithm for maintaining shortest path routing trees in stochastic networksINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 10 2004Sudip Misra Abstract This paper presents a new efficient solution to the Dynamic Shortest Path Routing Problem, using the principles of Generalized Pursuit Learning. It proposes an efficient algorithm for maintaining shortest path routing trees in networks that undergo stochastic updates in their structure. It involves finding the shortest path in a stochastic network, where there are continuous probabilistically based updates in link-costs. In vast, rapidly changing telecommunications (wired or wireless) networks, where links go up and down continuously and rapidly, and where there are simultaneous random updates in link costs, the existing algorithms are inefficient. In such cases, shortest paths need to be computed within a very short time (often in the order of microseconds) by scanning and processing the minimal number of nodes and links. The proposed algorithm, referred to as the Generalized Pursuit Shortest Path Algorithm (GPSPA), will be very useful in this regard, because after convergence, it seems to be the best algorithm to-date for this purpose. Indeed, it has the advantage that it can be used to find the shortest path within the ,statistical' average network, which converges irrespective of whether there are new changes in link-costs or not. Existing algorithms are not characterized by such a behaviour inasmuch as they would recalculate the affected shortest paths after each link-cost update. The algorithm has been rigorously evaluated experimentally, and it has been found to be a few orders of magnitude superior to the algorithms available in the literature. Copyright © 2004 John Wiley & Sons, Ltd. [source] Impact of different pasteurization temperatures on the survival of microbial contaminants isolated from pasteurized milkINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 2 2005PHOLISA DUMALISILE The thermal inactivation of selected microbes was studied using the low temperature long time (LTLT), high temperature short time (HTST) and ,pot' pasteurization methods. Survivors were enumerated after heating for up to 40 min for the LTLT and HTST pasteurization methods and after heating for up to 30 min for the ,pot' pasteurization method. With the exception of the Bacillus cereus strain, the selected microbes did not survive the LTLT and HTST pasteurization methods. The results from the ,pot' pasteurizer showed that B. cereus, Chryseobacterium meningosepticum, Pseudomonas putida, Acinetobacter baumannii and Escherichia coli strains survived the pasteurization conditions applied, showing that the ,pot' pasteurizer does not pasteurize effectively. [source] Dynamic characteristics of a PEM fuel cell system for individual housesINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 15 2006S. ObaraArticle first published online: 1 AUG 200 Abstract The method of determination of the control variables for a system controller, which controls the electric power output of a solid-polymer-membrane (PEM) fuel cell system during electric power load fluctuations, was considered. The operation was clarified for the response characteristics of electric power generation for setting the control variables of proportional action and integral action considered to be the optimal for the system controller. The power load pattern of an individual house consists of loads usually moved up and down rapidly for a short time. Until now, there have been no examples showing the characteristics of the power generation efficiency of a system that follows a load pattern that moves up and down rapidly. Therefore, this paper investigates the relation of the control variables and power generation efficiency when adding change that simulates the load of a house to PEM fuel cell cogeneration. As a result, it was shown that an operation, minimally influenced by load fluctuations, can be performed by changing the control variables using the value of the electric power load of a system. Copyright © 2006 John Wiley & Sons, Ltd. [source] An analytical and experimental analysis of a very fast thermal transientINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 11 2001C. Aprea Abstract According to some international standards, some products, developed for use under heavy thermal conditions, have to be tested by subjecting them for a short time to a particular heating and cooling thermal stress to allow them an acceptable future operative life. It is possible to obtain these fast thermal gradients in confined environments, called climatic chambers where the air is heated by an electrical resistance and is cooled with a finned evaporator which is linked to a vapour compression system subjected to a particular control system of the refrigerating power. In particular, in this paper the air and object tested thermal transients are studied from an analytical and experimental point of view. The study of the mathematical model is realized assuming simplified hypotheses about the air, the object and the air cooled evaporator temperature. The most complex circumstances are related to a very fast temperature decrease because under this working condition the mathematical model is characterized by a nonlinear differential system. The nonlinear term is represented by the refrigerating power that varies in a definite range with the evaporator temperature according to a sinusoid trend. For this power a suitable analytical expression, derived by the control system performance and by the compressor characteristic, has been found. The analytical,experimental comparison during a cooling thermal stress of typical products subjected to international standard tests as the electronic boards, has been carried out showing acceptable results. The model presented is useful to foresee the climatic chamber performances in the presence of a specific refrigerating power trend; this is the start-point for the design of the vapour compression plant and its control system. Copyright © 2001 John Wiley & Sons, Ltd. [source] Quality of applesauces processed by pulsed electric fields and HTST pasteurisation,INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2009Z. T. Jin Summary A pilot plant scale continuous flow pulsed electric field (PEF) and high temperature short time (HTST) processing system was integrated with an aseptic packaging machine. Fuji applesauce and blueberry applesauce were processed with PEF followed by HTST pasteurisation (PEF + HTST). PEF + HTST processed Fuji applesauce from fresh Fuji apples demonstrated high and stable sensory scores during 9 months storage at 27 °C, and had comparative sensory quality with Meal Read-to-Eat (MRE) and commercial applesauce products stored at 4 °C. PEF + HTST processed blueberry applesauce from pre-pasteurised materials had lower sensory scores than PEF + HTST processed Fuji applesauce and was significantly less stable during the storage at 27 °C. PEF + HTST processed applesauces had aerobic count and mould and yeast count of <10 cfu mL,1 during storage. Electrical conductivity, pH and °Brix, were not significantly changed throughout storage time (P > 0.05). [source] EPR study of thermally generated free radicals in nutsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 12 2007Nicola D. Yordanov Summary EPR studies of free radicals generated in roasting process of peanut, almond, walnut and apricot are reported separately for the kernels and flakes. The raw flakes exhibit a weak singlet EPR signal, whereas raw kernels are EPR silent. Two different EPR signals are recorded in the course of roasting. One in flakes with g = 2.0040, which is independent of temperature and time of roasting and is attributed to C-centered free radical. The same C-centered (g = 2.0040) free radical is recorded at high temperature (>140 °C) and for extended time (>20 min) of roasted kernels connected with burning of the material. However, an O-centered (g = 2.0048) free radical of ,lipid' type appears in kernels at roasting temperature of 100,140 °C and short time (5,20 min). On the contrary, free radical concentration in kernels and flakes increases with increase in roasting temperature and decreases with the time after that. The kinetics of the decay of free radicals concentration in flakes and kernels is followed at room temperature under the storage environment (air or argon). [source] Decontamination of deboned chicken legs by vacuum-tumbling in lactic acid solutionINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 1 2006François Deumier Summary Vacuum tumbling in a 1,5% lactic acid solution for a short time (1,10 min) improves the microbiological quality of deboned chicken legs, while inducing a light acidification and water absorption. The most significant variable of the process is the tumbling speed. High tumbling speeds lead to a high decontamination level of the chicken legs with regard to total viable counts and Enterobacteriaceae. Sodium lactate alone is unable to induce any decontamination at the same concentrations. Decontamination is probably more linked to acidification than to lactate ions. The use of vacuum tumbled (1 min in a 1% lactic acid solution) deboned chicken legs in the industrial manufacture of fresh chicken sausages led to a clear decrease in the number of Salmonella -positive batches. The incidence of positive batches was reduced threefold and the acid decontamination process did not adversely affect the sensory quality of the sausages. [source] Systematic design method of stabilization fuzzy controllers for pendulum systemsINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 8 2001Jianqiang Yi A systematic method to construct stabilization fuzzy controllers for a single pendulum system and a series-type double pendulum system is presented based on the single input rule modules (SIRMs) dynamically connected fuzzy inference model. The angle and angular velocity of each pendulum and the position and velocity of the cart are selected as the input items. Each input item is given with a SIRM and a dynamic importance degree. All the SIRMs have the same rule setting. The dynamic importance degrees use the absolute value(s) of the angle(s) of the pendulum(s) as the antecedent variable(s). The dynamic importance degrees are designed such that the upper pendulum angular control takes the highest priority and the cart position control takes the lowest priority when the upper pendulum is not balanced upright. The control priority orders are automatically adjusted according to control situations. The simulation results show that the proposed fuzzy controllers have high generalization ability to completely stabilize a wide range of single pendulum systems and series-type double pendulum systems in short time. By extending the architecture, a stabilization fuzzy controller for a series-type triple pendulum system is even possible. © 2001 John Wiley & Sons, Inc. [source] Quantification of red blood cell fragmentation by the automated hematology analyzer XE-2100 in patients with living donor liver transplantationINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 5 2005S. BANNO Summary The fragmented red cell (FRC) is a useful index for diagnosing and determining the severity of thrombotic thrombocytopenic purpura (TTP), thrombotic microangiopathy (TMA) and other similar conditions, as it is found in peripheral blood in patients with these diseases. The FRC expression rate has conventionally been determined by manual methods using smear samples. However, it is difficult to attain accurate quantification by such methods as they are time consuming and prone to a great margin of error. With cases of living donor liver transplantation, the current study examined the possibility of using a multi-parameter automated hematology analyzer, the XE-2100 (Sysmex Corporation) for FRC quantification. While there was a notable correlation between the manual and automated measurements, the manual measurement resulted in higher values. This suggested remarkable variations in judgment by individuals. The FRC values had a significant correlation with the reticulocyte count, red blood cell distribution width (RDW), fibrin/fibrinogen degradation products (P-FDP) and lactate dehydrogenase (LDH) among the test parameters, and this finding was consistent with the clinical progression in patients. The automated method can offer precise measurements in a short time without inter-observer differences, meeting the requirement for standardization. The determination of FRC count (%) by the XE-2100 that enables early diagnoses and monitoring of TTP or TMA will be useful in the clinical field. [source] Highly Chemo- and Regioselective Reduction of Aromatic Nitro Compounds Catalyzed by Recyclable Copper(II) as well as Cobalt(II) PhthalocyaninesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2010Upendra Sharma Abstract Copper/cobalt phthalocyanines were established for the first time as catalysts for the very efficient chemo- and regioselective reduction of aromatic nitro compounds to generate the corresponding amines. The selective reduction of nitro compounds was observed in the presence of a large range of functional groups such as aldehyde, keto, acid, amide, ester, halogen, lactone, nitrile and heterocyclic functional groups. Furthermore, the present method was found to be highly regioselective towards the reduction of aromatic dinitro compounds in a short time with high yields. In most of the cases the conversion and selectivity were >99% as monitored by GC-MS. The reduction mechanism was elucidated by UV-vis and electrospray ionization quadrupole time-of-flight tandem mass spectrometry. [source] Automated application component placement in data centers using mathematical programmingINTERNATIONAL JOURNAL OF NETWORK MANAGEMENT, Issue 6 2008Xiaoyun Zhu In this article we address the application component placement (ACP) problem for a data center. The problem is defined as follows: for a given topology of a network consisting of switches, servers and storage devices with varying capabilities, and for a given specification of a component-based distributed application, decide which physical server should be assigned to each application component, such that the application's processing, communication and storage requirements are satisfied without creating bottlenecks in the infrastructure, and that scarce resources are used most efficiently. We explain how the ACP problem differs from traditional task assignment in distributed systems, or existing grid scheduling problems. We describe our approach of formalizing this problem using a mathematical optimization framework and further formulating it as a mixed integer program (MIP). We then present our ACP solver using GAMS and CPLEX to automate the decision-making process. The solver was numerically tested on a number of examples, ranging from a 125-server real data center to a set of hypothetical data centers with increasing size. In all cases the ACP solver found an optimal solution within a reasonably short time. In a numerical simulation comparing our solver to a random selection algorithm, our solver resulted in much more efficient use of scarce network resources and allowed more applications to be placed in the same infrastructure. Copyright © 2008 John Wiley & Sons, Ltd. [source] Controlled and dependent: experiences of living on social assistance in SwedenINTERNATIONAL JOURNAL OF SOCIAL WELFARE, Issue 2 2010Anneli Marttila Marttila A, Whitehead M, Canvin K, Burström B. Controlled and dependent: experiences of living on social assistance in Sweden Int J Soc Welfare 2010: 19: 142,151 © 2009 The Author(s), Journal compilation © 2009 Blackwell Publishing Ltd and the International Journal of Social Welfare. This study explored experiences of people receiving social assistance in 21st-century Sweden, based on 33 in-depth interviews conducted in 2005 and 2006. Two overarching themes emerged from the accounts, encompassing both a material and a psychosocial dimension of living on social assistance. Recipients reported that social assistance was generally sufficient for their basic material needs but allowed for no extras. It was possible to live on social assistance for a short time, but became difficult in the longer term. Perceptions of powerlessness, hopelessness and dependency were common and had the most damaging consequences for the recipients' perceived wellbeing. Some recipients believed that society at large had negative perceptions of people living on social assistance; it was something to be ashamed of but, at the same time, it was the recipients' only possible source of income. Findings of this study are partly similar to previous studies conducted in Sweden, suggesting that improvement in services should take into account the experiences of social assistance recipients. [source] | ||||||||||||||||||||||||||||||||||||||||||||||