Stress Dependence of Transformation Plastic Behavior

Transformation plasticity is known to play an important role in the course of heat treatment processes, and so affect the results of heat treatment simulations, which means that the transformation plasticity coefficient is necessary to be identifies. The authors developed a new method by use of four-point bending system of a beam to identify transformation plasticity coefficient taking advantage of its easiness and high accuracy compared with other conventional methods like tension test, etc., and identified the coefficient for four kinds of steels; plane carbon steel, Cr-steel, Cr-Mo steel and bearing steel. In this paper, further experimental data are presented for the steels if the coefficient Kp during pearlite transformation depend on the applied stress. Obtained results reveals that the stress dependence of Kp is rather trivial except for uncertain tendency detected in plane carbon steel. The relation between the Kp and carbon content included is discussed in comparison with other data referred from references.

Sensitivity Numerical Analysis of Human Body Exergy Balance under an Unsteady-State Thermal Environment —Behavioral Adaptation Induced by Undesirable Cold Storage by Building Envelope in Winter

We analyzed the relationships between the human body exergy balance and behavioral adaptations induced by undesirable cold storage by a building envelope under an unsteady-state thermal environment in winter. The complex interaction of the warm exergy production by shivering, lifting of the shell ratio, and reduction of the blood flow rate was considered to constitute the physiological adaptation necessary for maintaining the constant core temperature, which was an important aspect in living organisms. In the case of intermittent use room, it was suggested that better thermal comfort and desirable behavioral adaptations, which decreased the consumption of fossil fuels, could be achieved if interior wooden cladding was used in constructions with building envelopes that had a comparatively large heat capacity, or in cases of wooden constructions in which the building envelope heat capacity was comparatively small.

Flip-Flop Flow Control inside Streamwise Diverging Diamond-Shaped Cylinder Bundles with Concavities

The flow visualization work with the aid of PIV and Piezometer deals with flip-flop flow around diamond-shaped cylinder bundle revised with concavities on both bundle walls. It is disclosed that 1) the concavity constructed on both side-walls of a diamond cylinder induces a substantial change in the flow patterns in the exit jet-stream field and jet- stream dispersion, 2) pressure characteristics are quantitatively measured in a diverging-flow region in diamond cylinder bundles with concavityand in its downstream region, and 3) flip-flop flow occurs in the flow passages and its occurrence condition is obtained.

Relationship between Pectic Substances and Strand Separation of Cooked Spaghetti SquashmPart 1. Changes in Pectic Substances during Cooking

The purpose of this paper is to investigate the relationship between pectic substances and the separation into strands during cooking of spaghetti squash. Spaghetti squash flesh separated into strands when boiled. Pectic substances of raw and cooked flesh were fractionated into three reagents. The galacturonic acid compositions of hydrochloric acid （HC1）-soluble pectin （PA）, sodium acetate buffer-soluble pectin （PB） and sodium hexametaphosphate-soluble pectin （PC） of raw flesh were 69.0%, 28.9% and 2.1%, respectively. Also, the degree of esterification （DE） ofPA, PB and PC was 67.4%, 61.5% and 55.6%, respectively. The DE of pectin was from the greatest to the least： PA 〉 PB 〉 PC, respectively, and the diethylaminoethyl （DEAE）-cellulose column chromatograms of PA and PB showed that they were comparatively in high methoxyl pectin. Therefore, about 50% of pectic substances in flesh were released into a cooking solution during 15-30 min of cooking. Highmethoxylpectin was degraded by β-elimination during boiling. Consequently, the flesh was separated into strands. This suggests that highmethoxylpectin glues strands together in the flesh of spaghetti squash.

Changes in Texture, Structure and Pectin of Peach during Pressurization, Heating or Processing of High-pressure-induced and Heat-induced Jam

The objectives of this study are to research the relationship between pectin and the softening of peach by soaking in citric acid solutions for 24 h at 35 ℃, pressurizing for 30 rain at 500 MPa or heating for 10 min. Also, comparing high-pressure-induced jam （HP-jam） and heat-induced jam （H-jam） were evaluated. It was found that firmness of the peach decreased greatly when soaked at pH 2.0 〉 heated 〉 soaked at pH 2.2 or 2.5 〉 pressurized, respectively. About 88% of the peach pectin was water-soluble-pectin and high-methoxyl pectin, while low-methoxyl pectin was slight. During pressurization, the pectin did not change. However, pectin degraded through hydrolysis during heating; consequently, the middle lamella separated. Also, eight kinds of peach jam （65% sugar, pH 2.0 or pH 2.2, and 50% or 60% sugar, pH 2.5） were compared. Both color and flavor of HP-jam were better than H-jam. As the pH values were lower, L-, a-, b-values of jam became higher, and the jam became pinker. Raw peach contained about 0.3%-0.4% pectin, therefore, an addition of 0.6% pectin was needed for both HP- and H-jams. However, there was no great difference in rheology or sensory evaluation between HP- and H-jams.

The Quality of High Pressure-Induced and Heat-Induced Hyuganatsu Marmalade

Hyuganatsu is a typical Japanese citrus with desirous smell and edible albedo. The objectives of this study are to establish a method for softening hyuganatsu peel without heating and a process for making a high pressure-induced （HP-） marmalade and to compare with heat-induced （H-） marmalade and citrus shaddock family marmalade. Firmness of peel was （greatest to least） pressurized at 500 MPa for 30 min, soaked in citric acid solution at pH 2.7 for 24 h, and boiled for 10 min, respectively. The cell walls of flavedo and albedo did not loosen after pressurization. However, after soaking or heating, the middle lamella of albedo separated. When flavedo was soaked at pH 2.7, 9.3% of pectin was extracted. The amount of naringin was the least in hyuganatsu 〈 pummelo 〈 grapefruit）, and juice sacs 〈 flavedo 〈 segment walls 〈 albedo, respectively. Thus, marmalade was processed. Albedo, segment walls and juice sacs of hyuganatsu were homogenized with citric acid solution （pH 2.7） and mixed with sliced flavedo. Then it was soaked for 24 h at pH 2.7. Sucrose was then added （final sugar 50%）, vacuum packed, then pressurized for 30 min at 500 MPa or boiled for 10 min, respectively. There was no significant difference in sensory evaluation between HP- and H-marmalade. However, the color, transparency and total evaluation of HP-marmalade were better than H-marmalade. Consequently, total evaluation of hyuganatsu-HP-marmalade was rated highly. So, hyuganatsu was considered to be more suitable for marmalade because it was more palatable than the others.

Relationship between Pectic Substances and Strand Separation of Cooked Spaghetti Squash--Part 2. Changes in Firmness, Histological Structure and Pectic Substances during Soaking in Pectin Extractants

The flesh of spaghetti squash separates into strands when cooked. The purpose of this paper is to investigate the cause of strand separation （during cooking） by soaking for 24 h at 35 ℃ in solutions with three kinds of pectin extractant. The changes in strand separation, firmness, histological structure and the pectin of flesh during soaking in 0.01 N HCI solution （pH 2.0）, 0.035 M ammonium oxalate solution （pH 4.0） or 2% sodium hexametaphosphate solution （pH 4.0） were investigated. When flesh was soaked in the HCI solution, the separation into strands and removal of calcium and magnesium were greater than that soaked in other pectin extractants. High methoxyl pectin was extracted by soaking in HC1 solution （pH 2.0） due to removal of polyvalent cations. This result shows that high methoxyl pectin glues strands together in the flesh of spaghetti squash. The shape of the cells which constituted strands was round; on the other hand, that of cells surrounded strands was elongated. When cooked in boiling water or soaked at pH 2.0, the shape of the former cells was maintained, but the latter cells, which contributed to adhesion between strands, broke down. Thus, the flesh separated into strands. When flesh was boiled for 15-30 min, pectin degraded and dissolved in the cooking solution; consequently, the flesh separated into strands and also the middle lamella of cell walls of strands separated. However, pectin remaining in strands maintained their crispness.

Approach to Epidemiological Mechanism of Infection or Colonization of Egg-Laying Chicken Farms by <i>Salmonella enterica</i>Serovar Enteritidis (SE) Becoming the Main Source of Contamination in Food Poisoning (Review)

Salmonella enterica serovar Enteritidis (SE)-induced diarrhea in humans is the typical non-typhoid diarrhea. It develops acutely or subacutely and may be fatal. This SE infectious disease suddenly became a major public health issue worldwide in the 1980s. The main causative food material of SE food poisoning is chicken eggs, and many outbreaks of food poisoning caused by chicken eggs occurred throughout the world. SE epidemics occurred in layer farms, and this was the main cause of SE-induced food poisoning in humans. The major subject of our epidemiological study described in this report is why SE-contaminated eggs became the main causative food. In this study, we focused on difference of molecular expression for farm-isolated SEs. That is because recent studies have demonstrated that O-antigen enlargement may be related to pathogenicity in mice as well as 22-kDa polypeptide-expression (SEp22). We have discovered that many SE strains isolated from chicken farms do not express SEp22, and a deficiency or decreased level of cellular antigen 0-12 in SE strains isolated from chicken farms was clarified in a report. Additionally, SEp22 was deficient in SE strains passaged through chickens, whereas SEp22 was expressed at a high level in SE strains passaged through mice. These findings suggest that SE infection and retention more effectively occur in layer farms than in other animal maintenance environments, which may be a basis of the epidemiological hypothesis to explain the high-levelproduction of SE-contaminated eggs (the presence of mice may be the basis of the retention of SE infection in layer farms, and this may also be the mechanism causing the high-level production of SE-contaminated eggs).