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Heating
Kinds of Heating Terms modified by Heating Selected AbstractsSPLITTING AND BREAKING OF PISTACHIO NUTS WITH STRIKING AND HEATINGJOURNAL OF FOOD PROCESS ENGINEERING, Issue 3 2008H.I. CEM BILIM ABSTRACT The objective of this study was to investigate the effects of heating process and striking on splitting and breaking of pistachio nuts and obtaining their kernels without damage. For this purpose, heating process (350C) was applied to pistachio nuts. Heated nuts were dropped onto the rotating disk and then thrown to strike the wall of the container by centrifuge effect . Striking velocity was adjusted with a rotating disk that was driven by an electrical engine. Three different disk rotations (400, 500 and 600/min) with three different moisture contents of pistachios (6.5, 22.0 and 42.5%) were evaluated in the experiments. Results indicated that the highest splitting rate was obtained as 29.33% at 22.0% moisture content with 400 1/min disk velocity. The most healthy kernel percentage obtained from unsplit pistachio nuts was 25.76% at 6.5% moisture content with 500 1/min disk velocity. Additionally, the study results showed that only the heating process had no affect while heating and crushing combinations increased splitting and obtaining the kernels. PRACTICAL APPLICATIONS Consumption of healthy foods is very important for human health. Kirmizi variety of pistachio nuts contains a high ratio of unsplit pistachio nuts after harvest. These pistachio nuts are either consumed as appetizers or used in the sweets sector after extracting the inner part (kernel). The economical value of unsplit pistachio nuts is very low. For this reason, pistachio nut processing plants try to split them or extract the inner part without causing any damage. Unsplit pistachio nuts are split by hand or by primitive hand tools, such as hammer or pliers, and then extracted. This method is not healthy. This study is one of the limited studies concerning automatic, quick and economic splitting and extraction of pistachio nuts. After handling problems like splitting and extracting the kernel of pistachio nuts, pistachio nut processing plants will achieve a healthy pistachio nut production. This study offers a new system for healthy pistachio nut production, with low initial cost, lower wages and in less time. [source] COMPUTER-CONTROLLED MICROWAVE HEATING TO IN-PACKAGE PASTEURIZE BEEF FRANKFURTERS FOR ELIMINATION OF LISTERIA MONOCYTOGENES,JOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2005LIHAN HUANG ABSTRACT The objective of this study was to develop an in-package pasteurization technology to kill Listeria monocytogenes in ready-to-eat meats using microwave heating. This technology utilized an infrared sensor to monitor the surface temperature of beef frankfurters during microwave heating. The aim was to increase the surface temperature of frankfurters to a set point lethal to L. monocytogenes. A feedback control mechanism was used to control the power to the microwave oven. Results indicated that the simple on-off control mechanism was able to maintain the surface temperature of beef frankfurters near the respective set points of 75, 80 or 85C used in this study. This pasteurization process was able to achieve a 7-log reduction of L. monocytogenes in inoculated beef frankfurters using a 600-W nominally rated microwave oven within 12,15 min. If optimized, this system may provide the food industry with a terminal, postlethality pasteurization technology to kill L. monocytogenes in ready-to-eat meats within the final packages. [source] DEVELOPMENT and EVALUATION of MICROWAVE HEATING of APPLE MASH AS A PRETREATMENT to PRESSINGJOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2004J.S. ROBERTS ABSTRACT Fuji, McIntosh, and Red Delicious apple mashes were heated in a 2450 MHz oven to achieve bulk temperatures of 40, 50, 60, and 70C. Three kilograms of mash at a depth of 0.016 m heated using 1500 W were the optimum parameters to heat apple mash in the microwave. Variety of the apple mash was shown not to have a significant effect on the heating performance. Comparing actual bulk temperature to the predicted bulk temperatures of 40, 50, 60, and 70C showed reproducibility of heating these mashes using microwave energy. Average variation between actual and predicted bulk temperatures were 1.48C for the Fuji mash, 0.98C for the McIntosh mash, and 1.13C for the Red Delicious mash. In addition, regional heating was investigated and four distinct regions of heating were observed: the corner, the edge, the middle, and the center. Color and moisture content of the mash were also measured and compared to unheated mash at 21C. [source] RADIO FREQUENCY (RF) HEATING OF STARCH SOLUTIONS UNDER CONTINUOUS FLOW CONDITIONS: EFFECT OF SYSTEM AND PRODUCT PARAMETERS ON TEMPERATURE CHANGE ACROSS THE APPLICATOR TUBEJOURNAL OF FOOD PROCESS ENGINEERING, Issue 3 2002G.B. AWUAH ABSTRACT Studies were conducted to evaluate the effect of system and product parameters on the temperature change (,T) across a 1.5 kW radio frequency heater operating at 27.12 MHz. Starch solutions (1 to 4% w/w) were used at three different flow rates (0.35, 0.5 and 1 L/min) and four power levels (672, 912, 1152 and 1392 W). The average heating rate of starch solutions varied from 6 to 19C/min depending on flow rate, concentration and power level. The corresponding residence time varied from 1.5 to 4.3 min. Central composite designs involving power (830 to 1234 W) and starch concentration (1 to 4% w/w) at 0.5 L/min were used to study the effects of salt, pH and sugar. As expected fluid flow rate, power level and salt concentration had significant impact (P ± 0.05) on temperature change (,T) across the applicator tube. Although the interaction effect of salt and concentration influenced ,T (P < 0.05), observed trends were not clear cut. Sugar and pH had no significant (P >0.05) influence on ,T due probably to their relatively lower conductivities. However, the interaction effect of sugar and starch concentration affected ,T. Correlations were developed for estimating ,T across the tube as a function of power level, concentration, pH, added salt and sugar. Finally, dimensionless correlations involving the generalized Reynolds, Prandtl, Grashof numbers, dimensionless power and loss-factor ratios were developed for estimating the temperature ratio (U) across the RF applicator. [source] DIFFUSION OF BEET DYE DURING ELECTRICAL AND CONVENTIONAL HEATING AT STEADY-STATE TEMPERATURE,JOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2001MARYBETH LIMA ABSTRACT Ohmic heating has been shown to alter mass transfer properties of fruit and vegetable tissue. Diffusion of beet dye from beetroot tissue into a fluid was studied during conventional and ohmic heating as a function of steady-state temperature. The volume of beet dye diffusing into solution during ohmic heating was enhanced with respect to conventional heating at 42C and 58C, but not at 72C. This can be explained by examining the differences in electrical conductivity of beet tissue at these temperatures during conventional and ohmic heating. At 42 and 58C, the electrical conductivity of beet tissue heated ohmically is higher than the electrical conductivity of beet tissue heated conventionally. At 72C, the electrical conductivities of beet tissue during conventional and ohmic heating are equal. The extent of diffusion in the ohmic case is also positively correlated with applied voltage. These results suggest that food processes involving mass transfer can be enhanced by choosing conditions in which the electrical conductivity of a sample under ohmic conditions is maximized. [source] EXTRACTION YIELD OF SOLUBLE PROTEIN AND MICROSTRUCTURE OF SOYBEAN AFFECTED BY MICROWAVE HEATINGJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2006IL CHOI ABSTRACT A laboratory-scale microwave (MW)-assisted extraction system was constructed and compared with a conventional shaking water bath regarding the extraction of soluble proteins in soybeans. Dynamic reaction was monitored by response surface methodology in the MW-assisted extraction system. The yield of soluble protein increased until either temperature (T) or water/solid (W/S) ratio reached an optimum point (60.1C, 12.6 mL/g), and then decreased with further increase of T or W/S ratio. In addition, the yield of soluble protein increased with time within a range of 30 min, and no critical point was observed. The molecular mass of soluble protein was distributed from 19.3 to 81.3 kDa estimated by sodium dodecyl sulfate,polyacrylamide gel electrophoresis. Scanning electron microscopy showed the destruction of the microstructure of soybean cells, which increased the extraction of soluble soy protein. [source] PHYSICAL PROPERTIES OF FISH PROTEINS COOKED WITH STARCHES OR PROTEIN ADDITIVES UNDER OHMIC HEATINGJOURNAL OF FOOD QUALITY, Issue 5 2007PANIDA PONGVIRAT CHAI ABSTRACT The texture, color and microstructure of surimi seafood gels were investigated to determine the interaction effects of fish proteins with starches or protein additives under ohmic heating, and to compare ohmically cooked gels with conventional water-bath-cooked gels. Gel properties were affected by the type of additive, concentration and cooking method. The effect of starch on gel texture was more pronounced at low concentrations. Compared to wheat starch, potato starch seemed to slightly improve gel strength; however, it decreased the gel whiteness. All nonfish protein additives resulted in better or equal textural properties of gels, whereas there was a slightly negative effect for gel color. Fast ohmic-cooked gels mostly exhibited higher gel strength than conventionally cooked gels. PRACTICAL APPLICATIONS There is a discrepancy between current gel preparation (slow heating by water bath) and current practice of crabstick manufacturing (fast heating). The use of data generated from slow cooking gel preparation for the manufacture of fast cooking crabstick does not make sense. This study demonstrates how starch and protein additives behave at ohmic heating which mimics the fast cooking crabstick manufacture. [source] IDENTIFICATION OF NONMEAT INGREDIENTS FOR INCREASING FAT HOLDING CAPACITY DURING HEATING OF GROUND BEEFJOURNAL OF FOOD QUALITY, Issue 4 2001E.T. ANDERSON ABSTRACT Eleven starch-, fiber-, and protein-based ingredients were evaluated for their fat holding capacity (FHC) in ground beef during heating. A test for FHC was developed where 20 g samples of 20% fat ground beef containing a 10% (wt/wt) addition of the selected ingredient were heated using low power microwave energy until internal temperatures were ,90C. Volumes of cooked-out water and fat were measured. FHC was determined based on the amount of fat released during cooking. High fiber ingredients retained more water and also had the highest FHC. Ground beef mixed with inner pea fiber retained the most fat, while the all-beef controls retained the least fat. Inner pea fiber appears to be a useful ingredient in the development of food products required to retain maximum amounts of fat during heating. [source] CHANGES IN TOMATO PASTE DURING STORAGE AND THE EFFECTS OF HEATING ON CONSISTENCY OF RECONSTITUTED TOMATO PASTEJOURNAL OF TEXTURE STUDIES, Issue 3 2010GORDON E. ANTHON ABSTRACT Bostwick consistencies of reconstituted tomato pastes were measured both immediately after paste production and after storage times of up to 9 months. Bostwick values measured after storage were more than twice those measured on the day of paste production. This increase in Bostwick developed over the first month of paste storage at room temperature and could be slowed down but not prevented if the paste was stored at 4C. Heating the reconstituted paste for 30 min at 90C or 15 min at 100C restored the original consistency. Serum viscosities also decreased during paste storage, but the change in serum viscosity was smaller than the changes in Bostwick. As with the Bostwick, heating the reconstituted juice restored the serum viscosity. For a reproducible evaluation of the consistency of stored tomato paste, it is essential that the reconstituted paste be heated to 90C or above. PRACTICAL APPLICATIONS Consistency is an important quality consideration in products prepared from reconstituted tomato paste. During storage, changes occur in tomato paste, which affect the consistency after reconstitution. The results presented here show that for stored tomato paste, heating after reconstitution restores consistency to the same level as measured before storage. This knowledge will help in the formulation of products made from stored tomato paste. [source] GELLING BEHAVIOR OF RICE FLOUR DISPERSIONS AT DIFFERENT CONCENTRATIONS OF SOLIDS AND TIME OF HEATINGJOURNAL OF TEXTURE STUDIES, Issue 3 2008ALKA KAPRI ABSTRACT Rice flour dispersions, under suitable conditions of processing, can form a gel. The effect of concentration of solids (10,18%) and time (0,75 min) of processing on textural attributes, and viscoelasticity were investigated along with sensory attributes. The textural attribute determined is gel strength, while viscoelasticity was determined in terms of mechanical spectra like storage modulus (G,), loss modulus (G,), complex viscosity (,*) and loss factor (tan ,) during a frequency sweep varying from 0.01 to 40 Hz at a constant stress of 25 Pa. Microstructural observation indicates the swelling of starch granules in the beginning of heating, while damaged granule and leached-out materials are visible at the end of the gelling process. Desirability function analysis has been applied to obtain a rice gel with acceptable textural attributes; a solid concentration of 15.2% and a heating time of 75 min can lead to the development of a gel with a satisfaction level of 0.6. PRACTICAL APPLICATIONS Rice flour gels in the form of hard-set gels, porridges and spreads are popular in several parts of the world particularly for feeding of infants and children. The application of the present study lies in understanding the role of major processing variables on the quality attributes and viscoelasticity of a product, characterization of cooked gels and for developing rice flour-based food gels. The findings may also be extended for the development of other cereal-based gels. [source] Optimization Study of ICRF Heating in the LHD and HSX ConfigurationsCONTRIBUTIONS TO PLASMA PHYSICS, Issue 6-7 2010S. Murakami Abstract Two global simulation codes, TASK/WM (a full wave solver) and GNET (a 5-D drift kinetic equation solver), are combined to simulate the ICRF heating in the 3D magnetic configuration. The combined code is applied to the ICRF minority heating in the LHD configuration. An optimization of the ICRF heating is considered in changing the magnetic configurations and the resonance surfaces in the LHD plasmas using GNET code. It is found that the heating efficiency is improved about 30% with the heating power of 10MW in the optimized heating scenario from that of the present standard off-axis heating scenario. Also the ICRF minority heating is studied in the HSX plasma and it is found that the ICRF heating of about 100kW is still effective to heat the plasma even , /a , 1/7.5 for tail ions (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Closure of the Greater Saphenous Vein with Endoluminal Radiofrequency Thermal Heating of the Vein Wall in Combination with Ambulatory Phlebectomy: Preliminary 6-Month Follow-upDERMATOLOGIC SURGERY, Issue 5 2000Mitchel P. Goldman MD Background. Incompetence of the saphenofemoral junction with reflux into the greater saphenous vein is one cause of chronic venous hypertension which may lead to the development of varicose and telangiectatic leg veins. Therefore treatment is necessary. Objective. To evaluate a novel method for closing the incompetent greater saphenous vein at its junction with the femoral vein through an endoluminal approach. Methods. Ten patients with reflux at the saphenofemoral junction into the greater saphenous vein were treated with radiofrequency heating of the vein wall through an endoluminal catheter. Patients were evaluated at 3 and 6 months to determine treatment efficacy as well as adverse sequelae. Results. All treated patients achieved complete closure of the saphenofemoral junction and greater saphenous vein. Complete treatment took an average of 20 minutes. Adverse sequelae were minimal, with 2 of 12 patients having mild erythema for 2,3 days. Conclusion. Endoluminal radiofrequency thermal heating of an incompetent greater saphenous vein has been shown to be easily accomplished and efficacious throughout the 6-month follow-up period. [source] A Dynamically Entangled Coordination Polymer: Synthesis, Structure, Luminescence, Single-Crystal-to-Single-Crystal Reversible Guest Inclusion and Structural TransformationEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 24 2010Arshad Aijaz Abstract A ZnII coordination polymer {[Zn2(cpa)2(bpy)]·3H2O}n (1) (cpa2, = 4-(methoxycarbonyl)benzoate and bpy = 4,4,-bipyridine) has been synthesized under solvothermal condition and structurally characterized. This coordination polymer has nanotubular threefold entangled (2D,3D) structure with embedded water molecules; the water molecules can be partially exchanged in reversible single-crystal-to-single-crystal (SC-SC) fashion by different solvent molecules like methanol, ethanol and acetone giving rise to {[Zn2(cpa)2(bpy)]·(0.5MeOH)·(2.5H2O)}n (2), {[Zn2(cpa)2(bpy)]·(0.5EtOH)·(0.5H2O)}n (3) and {[Zn2(cpa)2(bpy)]·(0.5Me2CO)·(H2O)}n (4). Inclusion of EtOH or MeOH leaves the size of the voids in the framework unaltered. Inclusion of acetone, however, is accompanied by shrinking of the voids in the framework. Heating of 1 at 100 °C under vacuum for 4 h affords the de-solvated compound, {Zn2(cpa)2(bpy)}n (1,). Single-crystal X-ray structure of 1, shows sliding of the individual nanotubular components expanding the overall framework. Thus, the coordination polymer exhibits dynamic motion of the molecular components in SC-SC fashion. All compounds were further characterized via IR spectroscopy, PXRD, elemental and TGA analysis. When 1 is placed in benzene at 100 °C for 2 days, compound {[Zn2(cpa)2(bpy)]·(2.5H2O)}n (5) is formed in a SC-SC fashion where coordination number of ZnII ion increases from four to five. Compound 1 also exhibits reversible guest-dependent photoluminescence properties. [source] Incorporation of a (Cyclopentadienyl)molybdenum Oxo Complex in MCM-41 and Its Use as a Catalyst for Olefin EpoxidationEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 24 2004Marta Abrantes Abstract The tricarbonyl complex [(,5 -C5H4 -COOMe)Mo(CO)3Cl] was prepared from the reaction of sodium (methoxycarbonyl)cyclopentadienide, (C5H4 -CO2Me)Na, with (Bu4N)[Mo(CO)5I]. Heating the ester with 3-(triethoxysilyl)propylamine gave the amide derivative {[,5 -C5H4 -CONH-C3H6Si(OEt)3]Mo(CO)3Cl}. The functionalised tricarbonyl complex was immobilised in the ordered mesoporous silica MCM-41 with a loading of 13 wt.-% Mo (1.4 mmol·g,1) by carrying out a grafting reaction in dichloromethane. Powder X-ray diffraction and nitrogen adsorption,desorption analysis indicated that the structural integrity of the support was preserved during the grafting and that the channels remained accessible, despite significant reductions in surface area, pore volume and pore size. The success of the coupling reaction was confirmed by 29Si and 13C (CP) MAS NMR spectroscopy. A supported dioxo complex of the type [(,5 -C5H4R)MoO2Cl] was subsequently prepared by oxidative decarbonylation of the tethered tricarbonyl complex using tert -butyl hydroperoxide (TBHP). The oxidised material is an active catalyst for the liquid phase epoxidation of cyclooctene with TBHP as the oxygen source. Similar catalytic results were obtained using the tethered tricarbonyl complex directly as a pre-catalyst since fast oxidative decarbonylation occurs under the reaction conditions used. For both systems, the desired epoxide was the only product and the initial activities were about 13 mol·molMo,1·h,1. The solid catalysts were recycled several times. Some activity was lost between the first and second runs but thereafter tended to stabilise. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Effect of termites on clay minerals in tropical soils: fungus-growing termites as weathering agentsEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 4 2002P. Jouquet Summary Termites of the subfamily Macrotermitinae play an important role in tropical ecosystems: they modify the soil's physical properties and thereby make food available for other organisms. Clay is important in the architecture of Macrotermitinae termite nests, and it has been postulated that termites could modify the mineralogical properties of some clays. We have tested this hypothesis of clay transformation by termites in the laboratory under controlled conditions, using Odontotermes nr. pauperans termite species, one of the main fungus-growing species at Lamto Research Station (Côte d'Ivoire). Soil handled by termites in nest building was saturated with SrCl2, glycol or KCl and afterwards heated at 250°C for X-ray diffraction analyses. Termite handling led to an increase in the expandable layers of the component clay minerals. Heating and saturation by potassium of modified clays did not close the newly formed expandable clay layers. However, differences occurred between parts of the constructions built by termites, and the clays can be ranked according to their degree of alteration in the following order: unhandled soils < galleries < chamber walls. Consequently, termites can be seen as weathering agents of clay minerals, as previously shown for micro-organisms and plants. [source] 6-(Diazomethyl)-1,3-bis(methoxymethyl)uracil, Synthesis and Transformation into Annulated PyrimidinedionesHELVETICA CHIMICA ACTA, Issue 7 2008Fuyi Zhang Abstract 6-(Diazomethyl)-1,3-bis(methoxymethyl)uracil (5) was prepared from the known aldehyde 3 by hydrazone formation and oxidation. Thermolysis of 5 and deprotection gave the pyrazolo[4,3- d]pyrimidine-5,7-diones 7a and 7b. Rh2(OAc)4 catalyzed the transformation of 5 into to a 2,:,1 (Z)/(E) mixture of 1,2-diuracilylethenes 9 (67%). Heating (Z)- 9 in 12n HCl at 95° led to electrocyclisation, oxidation, and deprotection to afford 73% of the pyrimido[5,4- f]quinazolinetetraone 12. The Rh2(OAc)4 -catalyzed reaction of 5 with 3,4-dihydro-2H -pyran and 2,3-dihydrofuran gave endo/exo -mixtures of the 2-oxabicyclo[4.1.0]heptane 13 (78%) and the 2-oxabicyclo[3.1.0]hexane 15 (86%), Their treatment with AlCl3 or Me2AlCl promoted a vinylcyclopropane,cyclopentene rearrangement, leading to the pyrano- and furanocyclopenta[1,2- d]pyrimidinediones 14 (88%) and 16 (51%), respectively. Similarly, the addition product of 5 to 2-methoxypropene was transformed into the 5-methylcyclopenta-pyrimidinedione 18 (55%). The Rh2(OAc)4 -catalyzed reaction of 5 with thiophene gave the exo -configured 2-thiabicyclo[3.1.0]hexane 19 (69%). The analoguous reaction with furan led to 8-oxabicyclo[3.2.1]oct-2-ene 20 (73%), and the reaction with (E)-2-styrylfuran yielded a diastereoisomeric mixture of hepta-1,4,6-trien-3-ones 21 (75%) that was transformed into the (1E,4E,6E)-configured hepta-1,4,6-trien-3-one 21 (60%) at ambient temperature. [source] Isolation and functional identification of a novel human hepatic growth factor: Hepatopoietin Cn,HEPATOLOGY, Issue 3 2008Chun-Ping Cui Hepatic stimulating substance (HSS) was first isolated from weanling rat liver in 1975 and found to stimulate hepatic DNA synthesis both in vitro and in vivo. Since then, mammalian and human HSS have been investigated for their potential to treat hepatic diseases. However, the essential nature in composition and structure of HSS remain puzzling because HSS has not been completely purified. Heating, ethanol precipitation, and ion-exchange chromatographies had been carried out to isolate the protein with specific stimulating activity from newborn calf liver, and [3H]thymidine deoxyribose (TdR)/bromodeoxyuridine (BrdU) incorporation and carboxyfluorescein diacetate succinimidyl ester (CFSE)-based proliferation assay to determine the bioactivity in vitro and in vivo. We report the purification of a novel 30-kDa protein from a crude extract of calf liver HSS. This protein is a member of the leucine-rich acidic nuclear protein family (LANP) and has been named hepatopoietin Cn (HPPCn). Studies of partially hepatectomized (PH) mice show that levels of HPPCn messenger RNA (mRNA) increase after liver injury. Furthermore, the recombinant human protein (rhHPPCn) was shown to stimulate hepatic DNA synthesis and activate signaling pathways involved in hepatocyte proliferation in vitro and in vivo. Conclusion: HPPCn is a novel hepatic growth factor that plays a role in liver regeneration. (HEPATOLOGY 2008;47:986,995.) [source] SERS-Coded Gold Nanorods as a Multifunctional Platform for Densely Multiplexed Near-Infrared Imaging and Photothermal HeatingADVANCED MATERIALS, Issue 31 2009Geoffrey von Maltzahn Screening nanorods coated with a mixture of SERS active molecules and biocompatible polymer identifies three formulations that may be uniquely distinguished in vivo over a spectral bandwidth of only 6,nm in the near-infrared (a spectral multiplexing density over an order of magnitude greater than attainable with semiconductor quantum dots, organic fluorochromes, and Raleigh scattering nanoparticle imaging approaches), while providing intense photothermal heating for cancer therapy. [source] Heating of indoor dust causes reduction in its ability to stimulate release of IL-8 and TNF, in vitro compared to non-heated dustINDOOR AIR, Issue 4 2004M. Mathiesen First page of article [source] Remote weather associated with North Pacific subtropical sea level high propertiesINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 5 2007Richard Grotjahn Abstract Remote events influencing North Pacific (NP) subtropical high properties in monthly and daily data are identified. Variability in the NP during summer is far more strongly dominated by midlatitude events than in South Pacific (SP); low-pass filtering is required to see tropical associations. The dominant pattern in composites, correlations, and regressions is a midlatitude wave train. A stronger NP high was led by higher sea-level pressure (SLP) just east of Japan and lower SLP over central Canada and to a lesser extent over western tropical Pacific. Various mechanisms have been proposed to force the NP high: (1)Heating over southwestern North America (with cooling off the west coast). However, higher temperatures over North America follow stronger SLP over the NP high and occur much further east than postulated. Higher SLP occurs where temperatures are lower over western North America and adjacent ocean. Thermal pattern is consistent with temperature advection between NP high and Canadian low. (2)Precipitation over and near Central America. However, SLP increase on the SE side of the high is led by higher SLP (and higher outgoing longwave radiation (OLR)) along the west coast of Mexico and Central America. Normalized regressions find a very weak lower OLR in North American monsoon preceding stronger NP high, but the region is much smaller in size and magnitude than other significant areas. (3)Precipitation over Indonesia and southeast Asia. Statistics provide some support for lower SLP and OLR over Indonesia preceding higher SLP in the center, west, and northwest sides of NP high. The lower SLP and OLR appear to migrate into southeast Asia, perhaps independently, perhaps from stronger NP high. (4)The NP high has a strong connection to El Niño during winter, but no significant link during summer. Only the south side of NP high appears (weakly) linked to the Madden Julian oscillation (MJO). Copyright © 2006 Royal Meteorological Society [source] Heating and cooling energy recovery for an HVAC system: Economic analysis for the Italian climateINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 8 2001Adolfo Palombo Abstract In this paper the economic analysis of the energy recovery in all-outdoor-air HVAC systems for the Italian climate is performed. The energy recovery device considered here is the same for both heating and cooling periods. During the summer season, the energy saving is achieved by evaporative cooling. The performances of the hybrid innovative HVAC system and the traditional system are calculated hour by hour by following the test reference year (TRY) profile. Such analysis is carried out taking into account simultaneously, the trend of some climatic indexes computed in order to (i) better understand the influence of climate on the HVAC system behaviour, (ii) obtain a swift feasibility analysis of the energy recovery system and (iii) perform a rough operating cost estimate of the traditional HVAC system. Copyright © 2001 John Wiley & Sons, Ltd. [source] Use of electron spin resonance measurements on irradiated sperma lentil seeds to indicate accidental irradiationINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 1 2003Mustafa Korkmaz Summary The results of electron spin resonance studies on ,-irradiated micro- and macrosperma lentil seeds are reported. Spectra of non-irradiated intact sperma were composed of an equally spaced sextet originating from the presence of Mn2+ ions and a single weak resonance line. Irradiation produced a linear increase in the radical signal intensity in the radiation dose range (0.5,5 kGy) studied, without affecting the Mn2+ signal. Signal intensities of both sperma followed compound exponential decay curves originating from the presence of three different radical species. Heating the sperma cause irreversible decreases in both radical and Mn2+ signal intensities. Two radical species, described in the present work, and a radical of unknown origin were used to explain the experimental results. [source] Palladium-Catalyzed Direct Arylations of 1,2,3-Triazoles with Aryl Chlorides using Conventional HeatingADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 5 2008Lutz Ackermann Abstract Generally applicable, palladium-catalyzed direct arylations of 1,2,3-triazoles with aryl chlorides were accomplished through conventional heating at reaction temperatures of 105,120,°C. Thereby, intra- and intermolecular CH bond functionalizations were achieved with a variety of differently substituted chlorides as electrophiles, bearing numerous valuable functional groups. [source] The infectivity of transmissible spongiform encephalopathy agent at low doses: the importance of phospholipidJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2006P. Gale Abstract The issue of whether the mechanism of infection is independent or co-operative for low doses of transmissible spongiform encephalopathy (TSE) agent is critical for risk assessment. The susceptibility (and hence ID50) of individuals with the same prion protein (PrP) genotype may vary considerably with a small proportion being very susceptible. Assuming independent action, the incubation period (IP) would continue to increase until the dose is below the ID50 of the most susceptible individuals in the experiment, at which point it would become constant. This may explain the observed increase in IP with decreasing dose below the apparent ID50 in experiments with untreated TSE agent. In contrast, IPs for autoclaved or NaOH-treated TSE agent increase greatly at doses Temperature shock, injury and transient sensitivity to nisin in Gram negativesJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2001I.S. Boziaris Aims:,The effect of thermal stresses on survival, injury and nisin sensitivity was investigated in Salmonella Enteritidis PT4, PT7 and Pseudomonas aeruginosa. Methods and Results:,Heating at 55°C, rapid chilling to 0·5°C or freezing at ,20°C produced transient sensitivity to nisin. Cells were only sensitive if nisin was present during stress. Resistance recovered rapidly afterwards, though some cells displayed residual injury. Injury was assessed by SDS sensitivity, hydrophobicity changes, lipopolysaccharide release and NPN uptake. LPS release and hydrophobicity were not always associated with transient nisin sensitivity. Uptake of NPN correlated better but persisted longer after treatment. Conclusions:,Thermal shocks produce transient injury to the outer membrane, allowing nisin access. After treatment, the permeability barrier is rapidly restored by a process apparently involving reorganization rather than biosynthetic repair. Significance and Impact of the Study:,Inclusion of nisin during food treatments that impose sub-lethal stress on Gram negatives could increase process lethality, enhancing microbiological safety and stability. [source] Real-Time Monitoring of Luminal Esophageal Temperature During Left Atrial Radiofrequency Catheter Ablation for Atrial Fibrillation: Observations About Esophageal Heating During Ablation at the Pulmonary Vein Ostia and Posterior Left AtriumJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2 2006CHRISTIAN PERZANOWSKI M.D. Introduction: Left atrial radiofrequency catheter ablation (RFA) is gaining acceptance as treatment for drug-refractory atrial fibrillation (AF). This therapy has been associated with esophageal injury and atrioesophageal fistula formation causing death. Methods: We describe 3 patients undergoing catheter ablation for AF during real-time monitoring of luminal esophageal temperature. Results: We observed heating of the esophagus during short duration low power RFA, at either the left or right pulmonary vein ostia. Cryoablation at the pulmonary vein ostium in one patient resulted in esophageal cooling. Furthermore, we observed that fluoroscopic localization of the ablation catheter at a site apparently distant from the esophagus is not adequate to assure avoidance of ablation-induced esophageal heating. Conclusions: Real-time monitoring of luminal esophageal position and temperature is feasible, enhances recognition of esophageal heating, and may add useful information beyond that provided by fluoroscopic assessment of esophageal position. There is a potential role for esophageal monitoring to help avoid thermal injury to the esophagus during catheter ablation for atrial fibrillation. [source] CORRELATION BETWEEN CITRIC ACID, THYMUS VULGARIS EXTRACT AND NaCl, AND HEAT SENSITIVITY AND CASEINASE PRODUCTION BY AEROMONAS CAVIAE AND A. SOBRIAJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 6 2008BAYAN M. ABU-GHAZALEH ABSTRACT The effects of citric acid, Thymus vulgaris extract and NaCl on the heat sensitivity of Aeromonas spp. were examined in three different situations in this study. First, the effects of pretreatment with nutrient broth plus 0.03% citric acid, nutrient broth plus 0.3% T. vulgaris extract, nutrient broth plus 2.5% NaCl or nutrient broth plus 3% NaCl on the survival and caseinase production by heated A. caviae 166 and A. sobria 74 were investigated. Pretreatment of Aeromonas spp. with these preservatives for 1 or 6 days significantly increased their resistance to subsequent heating at 54C. However, pretreatment of Aeromonas strains with nutrient broth plus 2.5% NaCl or nutrient broth plus 3% NaCl before heating at 54C significantly (P < 0.05) decreased the production of caseinase by the heated cells. Second, the effect of post-treatment with preservatives after heating of Aeromonas strains was examined. Post-treatment of Aeromonas strains with the tested preservatives for 7 days after heating at 54C for 20 min prevented a complete recovery of cells and decreased the caseinase production compared with Aeromonas cells that were incubated in nutrient broth alone for 7 days after heating at 54C. Third, the effect of the type of the heating menstruum on the heat sensitivity of Aeromonas strains was investigated in this study. Heating in NaCl (0.85%) containing citric acid (0.03%) was the most effective treatment in killing Aeromonas spp. Heating in NaCl (0.85%) containing T. vulgaris extract (0.3%) or in NaCl (3.85%) slightly increased the resistance of cells to heat. PRACTICAL APPLICATIONS The results obtained in this study can be applied in the food industry, where combination of mild heat treatment and addition of low doses of chemical preservatives to food is nowadays frequently used. This study determined the heat sensitivity and caseinase production by A. caviae and A. sobria at three different conditions that may be encountered during processing of food industrially or at home. Firstly, the effect of pretreatment with some preservatives on the heat sensitivity and caseinase production by the tested Aeromonas. spp. was studied. Secondly, the effect of post-treatment with preservatives on growth and caseinase production by the heated (54C) Aeromonas cells was investigated. Thirdly, effect of presence of preservatives in the heating menstruum on the heat sensitivity of Aeromonas spp. was studied. [source] Rheological Characteristics and Morphology of Dialdehyde Starch/Meat Composites during HeatingJOURNAL OF FOOD SCIENCE, Issue 2 2009P.Y. Chiang ABSTRACT:, Dialdehyde starch (DAS) was added to pork ham batter. The effects of DAS on the meat protein gel during heating were investigated using thermal and rheological analyses. In this study, the degree of DAS oxidation was controlled by the reaction time. The DSC thermogram showed that increasing the degree of oxidation resulted in DAS having a higher gelatinization temperature and lower heat absorption. In dialdehyde starch/meat (DAS/M) composites, meat protein reduced the availability of water to starch and raised the gelatinization temperature and heat absorbed by the composites. The G,max of the composites was greater than the linear combination of their components. The rheological properties of DAS were a major factor affecting the properties of its composites. Scanning electron microscopy and light microscopy with the aid of histologic technique revealed the network and distribution of DAS and DAS/M composites. The protein matrix formed the backbone of the network and gelatinized starch was trapped in the protein structure. [source] Comparison of Soybean Oils, Gum, and Defatted Soy Flour Extract in Stabilizing Menhaden Oil during HeatingJOURNAL OF FOOD SCIENCE, Issue 1 2008X. Yue ABSTRACT:, Capabilities of crude soy oil, degummed oil, gum, and defatted soy flour extract in preventing the oxidation of menhaden oil and its omega-3 fatty acids, DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid), during heating were evaluated. The menhaden oil mixed with defatted soy flour extract demonstrated the greatest stability by producing the lowest TBA reactive oxidation products and retaining the highest concentrations of DHA and EPA after heating at 150 °C for 30 min. A range of 62.8% to 71.5% of DHA and 67.7% to 75.9% of EPA remained in the fish oil with defatted soy flour extract, while only 29.9% of DHA and 37.2% of EPA were retained in the fish oil with no addition. Stabilizing capability from highest to lowest was defatted flour extract > gum > degummed oil = crude oil. The defatted flour extract had the highest level of total phenolic content (11.3 ,g catechin equivalent/g), while crude oil, degummed oil, and gum contained 7.1, 6.1, and 6.0 ,g catechin equivalent/g, respectively. The level of isoflavones in the defatted soy flour extract was 55 mg/g, which was over 100 times higher than in the crude oil or gum. Although isoflavones were not detected in the degummed oil, it contained the highest level of tocopherols (414 ,g/g), whereas the lowest level (215 ,g/g) was found in the defatted flour extract. The order of free radical scavenging capability measured from high to low was the defatted soy flour extract, crude oil, degummed oil, and gum. [source] The Effect of Electric Field on Important Food-processing Enzymes: Comparison of Inactivation Kinetics under Conventional and Ohmic HeatingJOURNAL OF FOOD SCIENCE, Issue 9 2004I. Castro ABSTRACT: This work deals with the determination of the inactivation kinetics of several enzymes, most of them used as time-temperature integrators in the food industry. The tested enzymes were polyphenoloxidase, lipoxygenase, pectinase, alkaline phosphatase, and p-galactosidase, and the inactivation assays were performed under conventional and ohmic heating conditions. The thermal history of the samples (conventional and ohmically processed) was made equal to determine if there was an additional inactivation caused by the presence of an electric field, thus eliminating temperature as a variable. All the enzymes followed 1st-order inactivation kinetics for both conventional and ohmic heating treatments. The presence of an electric field does not cause an enhanced inactivation to alkaline phosphatase, pectinase, and ,- galactosidase. However, lipoxygenase and polyphenoloxidase kinetics were significantly affected by the electric field, reducing the time needed for inactivation. The results of the present work can be used industrially to determine processing effectiveness when ohmic heating technology is applied. [source]
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