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Photothermal atomic force microscopy coupled with infrared spectroscopy (AFM-IR) brings significant value as a spatially resolved surface analysis technique for disordered oxide materials such as glasses, but additional development and fundamental understanding of governing principles is needed to interpret AFM-IR spectra, since the existing theory described for organic materials does not work for materials with high extinction coefficients for infrared (IR) absorption. This paper describes theoretical calculation of a transient temperature profile inside the IR-absorbing material considering IR refraction at the interface as well as IR adsorption and heat transfer inside the sample. This calculation explains the differences in peak positions and amplitudes of AFM-IR spectra from those of specular reflectance and extinction coefficient spectra. It also addresses the information depth of the AFM-IR characterization of bulk materials. AFM-IR applied to silica and silicate glass surfaces has demonstrated novel capability of characterizing subsurface structural changes and surface heterogeneity due to mechanical stresses from physical contacts, as well as chemical alterations manifested in surface layers through aqueous corrosion.

PurposeBased on a dyadic perspective, the purpose of this paper is to include the contributions of employee and customer in a service process and to examine the underlying mechanism of customer organization socialization on service performance.Design/methodology/approachThe authors used a unique survey data pertaining to the service industry. The authors collected their data from multiple sources (customers, front-line employees and these employees' managers) in the divisions of a large service organization – Ping An Insurance (Group) Company of China. The authors adopted hierarchical regression moderated path analysis approach to examine our moderated mediation model.FindingsThe authors find that both the quality of customer service and the quality of employee service play as moderators in the relationship between customer organization socialization and service performance. And quality of customer service moderates the relationship between customer organization socialization and quality of employee service.Originality/valueThe literature has focused primarily on service performance improvement based on the dyadic perspective of customer and employee. The research develops a moderated mediation model and contributes to the literature by empirically examining customer organization socialization.

The US plan for high-level nuclear waste includes the immobilization of long-lived radionuclides in glass or ceramic waste forms in stainless-steel canisters for disposal in deep geological repositories. Here we report that, under simulated repository conditions, corrosion could be significantly accelerated at the interfaces of different barrier materials, which has not been considered in the current safety and performance assessment models. Severe localized corrosion was found at the interfaces between stainless steel and a model nuclear waste glass and between stainless steel and a ceramic waste form. The accelerated corrosion can be attributed to changes of solution chemistry and local acidity/alkalinity within a confined space, which significantly alter the corrosion of both the waste-form materials and the metallic canisters. The corrosion that is accelerated by the interface interaction between dissimilar materials could profoundly impact the service life of the nuclear waste packages, which, therefore, should be carefully considered when evaluating the performance of waste forms and their packages. Moreover, compatible barriers should be selected to further optimize the performance of the geological repository system. Immobilization of radionuclides in glass or ceramic forms in stainless steel in deep geological repositories is planned in the US for disposal of nuclear waste. Under simulated repository conditions, corrosion could be significantly accelerated at the interfaces of different barrier materials.

Hydrogen bonding interactions play an important role in many chemical and physical processes occurring in bulk liquids and at interfaces. In this study, hydrous species (H2O and Si-OH) on nano-porous alteration layers (gels) formed on a boroaluminosilicate glass called International Simple Glass corroded in aqueous solutions at pH 7 and pH 9, and initially saturated with soluble silicon-containing species were analyzed using linear and non-linear vibrational spectroscopy in combination with molecular dynamics simulations. The simulation results revealed various possible types of hydrogen bonds among these hydrous species in nanoconfinement environments with their populations depending on pore-size distribution. The nano-porous gels formed on corroded glass surfaces enhance hydrogen bond strength between hydrous species as revealed by attenuated total reflectance infrared spectroscopy. Sum frequency generation spectroscopy showed some significant differences in hydrogen bonding interactions on alteration layers formed at pH 7 and pH 9. The glass dissolution under the leaching conditions used in this study has been known to be ten times faster at pH 7 in comparison to that at pH 9 due to unknown reasons. The simulation and experimental results obtained in this study indicate that the water mobility in the gel formed at pH 9 could be slower than that in the gel formed at pH 7, and as a result, the leaching rate at pH 9 is slower than that at pH 7.

Vanadium-containing glasses have aroused interest in several fields such as electrodes for energy storage, semiconducting glasses, and nuclear waste disposal. The addition of V2O5, even in small amounts, can greatly alter the physical properties and chemical durability of glasses; however, the structural role of vanadium in these multicomponent glasses and the structural origins of these property changes are still poorly understood. We present a comprehensive study that integrates advanced characterizations and atomistic simulations to understand the composition-structure-property relationships of a series of vanadium-containing aluminoborosilicate glasses. UV-vis spectroscopy, X-ray photoelectron spectroscopy, and X-ray absorption near-edge structure (XANES) have been used to investigate the complex distribution of vanadium oxidation states as a function of composition in a series of six-component aluminoborosilicate glasses. High-energy X-ray diffraction and molecular dynamics simulations were performed to extract the detailed short- and medium-range atomistic structural information such as bond distance, coordination number, bond angle, and network connectivity, based on recently developed vanadium potential parameters. It was found that vanadium mainly exists in two oxidation states: V5+ and V4+, with the former being dominant (∼80% from XANES) in most compositions. V5+ ions were found to exist in 4-, 5-, and 6-fold coordination, while V4+ ions were mainly in 4-fold coordination. The percentage of 4-fold-coordinated boron and network connectivity initially increased with increasing V2O5 up to around 5 mol % but then decreased with higher V2O5 contents. The structural role of vanadium and the effect on glass structure and properties are discussed, providing insights into future studies of sophisticated structural descriptors to predict glass properties from composition and/or structure and aiding the formulation of borosilicate glasses for nuclear waste disposal and other applications.

Unlike the existing gesture related research predominantly focusing on gesture recognition (classification), this work explores the feasibility and the potential of mid-air dynamic gesture based user identification through presenting an efficient bidirectional GRU (Gated Recurrent Unit) network. From the perspective of the feature analysis from the Bi-GRU network used for different recognition tasks, we make a detailed investigation on the correlation and the difference between the gesture type features and the gesture user identity characteristics. During this process, two unsupervised feature representation methods – PCA and hash ITQ (Iterative Quantization) are fully used to perform feature reduction and feature binary coding. Experiments and analysis based on our dynamic gesture data set (60 individuals) exemplify the effectiveness of the proposed mid-air dynamic gesture based user identification approach and clearly reveal the relationship between the gesture type features and the gesture user identity characteristics.

This study explores the corrosion interactions between model nuclear waste glass materials and corrosion resistant alloys, under accelerated conditions that simulate the near field of a nuclear waste repository. The interactions between the corrosion of stainless steel (SS) 316, alloy G30, or alloy 625, and international simple glass or soda-lime silica glass are systematically studied. The dissimilar materials were exposed in close proximity to each other in different electrolytes at 90 °C. After exposure, the glass surface exposed near metals showed different regimes of corrosion, with distinct surface morphologies and chemistries that were likely affected by the local environment created by the localized corrosion of metals. Surface and solution analyses showed that the corrosion rate of glass was enhanced by the presence of metals. Infrared spectroscopy data suggested the local build-up of stresses in the contact area of glass, which may lead to the mechanical instability of the glass alteration layer. On the other hand, the effect of glass on metal corrosion is strongly dependent on the leaching solution. In electrolytes containing abundant aggressive anions such as Cl−, glass seems to suppress the localized corrosion of SS by the precipitation of a Si-rich surface film that protects the SS substrate from solutions. However, in less aggressive electrolytes, the corrosion rate of SS was increased by the presence of glass corrosion products. Overall, our study showed that the hidden and localized damage on glass in contact with metals may enhance the release rate of glass components compared to typical uniform glass corrosion.

Transcriptional activation of p21 (cyclin-dependent kinase inhibitor 1A) due to DNA damage often alters the distribution of histone variant H2A.Z at the p21 gene. However, whether the human INO80 complex regulates changes in H2A.Z at the p21 promoter is unclear. We show here that activation of p21 expression by doxorubicin (Doxo) in U2OS cells is required for removal of H2A.Z by INO80 at the p53-binding site proximal region (-2.2 kb) of the p21 promoter. A purified INO80 complex, but not the INO80E653Q mutant-complex, which lost DNA-sliding activity, is mainly responsible for removing H2A.Z from reconstituted nucleosomes in vitro. This activity was enhanced with MOF-mediated histone acetylation, suggesting that INO80 more readily removes H2A.Z from loosened nucleosomes. Also, co-occupancy of INO80 and H2A.Z -2.2 kb upstream of the p21 transcriptional start site (TSS) was observed. H2A.Z at this region was removed in a short time after Doxo treatment and activated p21 expression. However, p21 induction was inhibited by INO80 knockdown by delaying H2A.Z removal, indicating the need for INO80. Moreover, shMOF-mediated histone acetylation reduced recruitment of INO80 -2.2 kb upstream of p21 TSS and inhibited the removal of H2A.Z in Doxo-treated cells. These data provide new insights into the transcriptional regulation of p21 by the INO80 complex.

The porosity and pore-size distribution in the glass play an important role in glass corrosion; however, such information is difficult to be obtained non-destructively. Here we report the use of spectroscopic ellipsometry (SE) under controlled humidity environments to determine those structural parameters in the alteration layers formed on international simple glass (ISG), a model nuclear waste glass, in aqueous corrosion conditions. The SE results show that the ISG sample corroded for nearly 4.5 years develops pores larger than 2 nm in diameter, while the alteration layers formed initially in less than 1 month do not have such large pores. The development of larger pores over a long period of corrosion time, while the overall thickness remains relatively constant, implies structural rearrangements of the silicate network occurring within the alteration layer, which could eventually affect the transport of reactants and products as well as the structural stability. Spectroscopy has been used to study the interfacial silica gel layer created during the corrosion of a model nuclear-waste glass. Understanding the way in which such materials degrade is of great importance because they are used to store radioactive waste. When international simple glass (ISG) corrodes an ‘alteration’ layer forms on its surface and now Seong H. Kim, from The Pennsylvania State University, and co-workers have used spectroscopic ellipsometry to characterize the thickness, porosity, and pore-size distribution of this layer after exposing it to different corrosive experimental conditions. Their data show that, although their alteration layers are of similar depths, the pore diameters in ISG samples corroded for 7 or 28 days are smaller than 2 nm whereas those corroded for 1625 days are larger, implying some restructuring of the layer over this time.

Satellite imagery is a kind of typical remote sensing data, which holds preponderance in large area imaging and strong macro integrity. However, for most commercial space usages, such as virtual display of urban traffic flow, virtual interaction of environmental resources, one drawback of satellite imagery is its low spatial resolution, failing to provide the clear image details. Moreover, in recent years, synthesizing the color for grayscale satellite imagery or recovering the original color of camouflage sensitive regions becomes an urgent requirement for large spatial objects virtual reality interaction. In this work, unlike existing works which solve these two problems separately, we focus on achieving image super-resolution (SR) and image colorization synchronously. Based on multi-task learning, we provide a novel deep neural network model to fulfill single satellite imagery SR and colorization simultaneously. By feeding back the color feature representations into the SR network and jointly optimizing such two tasks, our deep model successfully achieves the mutual cooperation between imagery reconstruction and image colorization. To avoid color bias, we not only adopt the non-satellite imagery to enrich the color diversity of satellite image, but also recalculate the prior color distribution and the valid color range based on the mixed data. We evaluate the proposed model on satellite images from different data sets, such as RSSCN7 and AID. Both the evaluations and comparisons reveal that the proposed multi-task deep learning approach is superior to the state-of-the-art methods, where image SR and colorization can be accomplished simultaneously and efficiently.

Employing circumferentially uniform air flow through the sheath layer of the concentric coaxial nozzle, the gas-assisted electrospinning (GAES) utilizes both high electric field and controlled air flow to produce nanofibers. The ability to tailor the distribution of various nanofillers (1.85-12.92 vol% of spherical SiO2 and Si nanoparticles) in a polyvinyl alcohol jet is demonstrated by varying airflow rates in GAES. The distribution of nanofillers is measured from transmission electron microscopy and is analyzed using an image processing technique to perform the dispersion area analysis and obtain the most probable separation between nanoparticles using fast Fourier transform (FFT). The analysis in this study indicates an additional 350% improvement in dispersion area with the application of high but controlled airflow, and a 75 percent decrease in separation between nanoparticles from the FFT. The experiments in this study are in good agreement with a coarse-grained MD simulation prediction for a polymer nanocomposite system subjected to extensional deformation. Lastly, utilizing the sheath layer air flow in production of Li-battery anode material, a 680 mAh g-1 improvement is observed in capacity for nanofibers spun via GAES compared to ES at the same Si NP loading, which is associated with better dispersion of the electrochemically active nanoparticles.

In this study, we applied a series of surface analysis techniques to explore the structure and chemistry of the corrosion products built up at the interface of different materials, which is relevant to the permanent disposal of world-wide high-level nuclear waste. Metallic alloys, amorphous glass, and crystalline ceramics are typical candidate nuclear waste forms planned for immobilizing and isolating the dangerous radionuclides enriched in the waste. The near-field corrosion interactions between these dissimilar materials are the focus of this study. The experiments were performed by corroding metallic alloys in intimate proximity to glass or ceramics in Cl--containing solutions at 90 oC. The exposed materials were subsequently subjected to comprehensive surface characterization using X-ray photoelectron spectroscopy, scanning transmission electron microscopy, energy dispersive spectroscopy, time-of-flight secondary ion mass spectrometry, and Raman/infrared spectroscopy analysis. The systematic study revealed localized damage on the alloy surface due to crevice corrosion. Interestingly, localized corrosion was also identified on the surface of some glasses and ceramics that were present nearby, while an inhibition effect was observed in other systems. These interactions were found to strongly depend on the type of materials and environment, which led to different corrosion phenomena.

BackgroundWith the rapid increase in ageing population, China is confronted with the daunting challenge of a growing number of patients with neurocognitive disorders (NCDs). This trend makes the maintenance of self-health and early intervention essential, highlighting the need for a tool that assesses self-efficacy of older adults in maintaining brain health or cognitive function.AimThis study aimed to design the Brain Health Self-Efficacy Scale (BHSES) to measure elderly individuals’ attitudes to NCDs, motivations and future plans for controlling risks. The psychometric properties of BHSES have been validated.MethodsBased on the current literature and relevant models, a 19-item scale was created during the first stage. A total of 660 older adults in the Yinhang community of Shanghai were included. The statistical approaches of item analysis, exploratory factor analysis (EFA), confirmatory factor analysis (CFA), criterion-related validity and reliability test were used to evaluate the quality of BHSES. In addition, the Geriatric Depression Scale (GDS) and the Self-Rating Anxiety Scale (SAS) were used as criteria to test the criterion-related validity.ResultsTo test item differentiation, the study adopted item analysis and excluded item 8. Selecting a random half of the sample for EFA, the BHSES was refined to 16 items, which were categorised into the following three dimensions: ‘memory belief efficacy’, ‘self-care efficacy’ and ‘future planning efficacy’. These were highly consistent with the hypothesis model. Its cumulative variance contribution rate reached 61.14%, with factor loads of all items above 0.5. The three-factor model was confirmed by the remaining data through CFA. All fit indices reached the acceptable level (χ2=3.045, Goodness of Fit Index=0.898, adjusted Goodness of Fit Index=0.863, Comparative Fit Index=0.916, Incremental Fit Index=0.917, Tucker-Lewis Index=0.900, root mean square error of approximation=0.079 and root mean residual=0.068). The GDS and SAS scores revealed significant correlations with the BHSES score, indicating a high criterion-related validity. The overall Cronbach’s α coefficient was 0.793, with the α coefficients’ distribution of subdimensions ranging from 0.748 to 0.883.ConclusionsThe 16-item, self-compiled BHSES is a reliable and valid measurement. It could help identify older adults with potential risks for developing NCDs or with high suspicion of cognitive impairment onset in recent periods and also offer insight into tracking brain health self-efficacy in association with cognition status.

The mixed alkaline earth effect (MAEE) is important for several families of industrial borosilicate and aluminosilicate glasses, including glasses used in pharmaceutical packaging and as substrates for flat panel displays. Despite the technological importance of the mixed alkaline earth effect, the physical origin of this phenomenon is not well understood, and there is currently no model to offer quantitative prediction of the effect. In this work, the MAEE is studied both experimentally and through modeling in a series of boroaluminosilicate glasses with systematic substitution of CaO with MgO. The network structure is characterized by magic angle spinning nuclear magnetic resonance (MAS NMR) analyses of 27Al, 11B, 29Si, and 23Na. Molecular dynamics (MD) simulations are conducted to simulate the glass structures and calculate the evolution of the bond angle distributions with composition. Based on the structural data, a topological constraint model is proposed to capture the MAEE on glass transition temperature (Tg), liquid fragility index (m), and Young's modulus (E) of the glasses. Results of the topological constraint model are in good quantitative agreement with experimental data. The success of the constraint model confirms that the mixed alkaline earth effect is the result of a shift in angle around oxygen in the cation-oxygen-cation bond in the glass network. This is related to the constraint strength that ultimately governs the nonlinear property variation.

Multi-wall carbon nanotubes (CNTs) and their unzipped counterparts graphene nanoribbons (GNRs) are promising materials for energy storage applications, due to their unique architecture and properties. However, spatial distribution and orientation in polymer matrices plays a crucial role in determining the charge and mass transfer effectiveness of the nanocomposite. Here, we report a controlled enhancement of dispersion and spatial alignment of CNTs and GNRs via gas-assisted electrospinning (GAES). This methodology obviates the use of surface modifications to ensure effective enthalpic interactions between a substrate and filler, and offers a “single-step” procedure for electrode fabrication. We conducted a rigorous TEM image analysis of as-spun PVA nanofibers and observed an average of 60 and 90% improvement in dispersion area due to the application of high but controlled air flow for CNTs and GNRs, respectively. Alignment results demonstrate that stiff CNTs respond uniformly to the external deformation applied by GAES, while more flexible GNRs have a limited response.

A starch modification reactor has been established using a HAAKE rheometer incorporating a twin-roll mixer, which has been modified to improve its sealing and feeding, and to establish an oxygen-free environmental. The advantages of the system include: (i) starch modification can be carried out at high starch concentration (up to 70%); (ii) combining the steps of starch gelatinization and chemical modification; (iii) controllable reaction time; and (iv) smaller sample size (60 g) requirement. The effects of water content, rpm, time, and temperature on the reactive system was systematically investigated. Corn starch (60% starch concentration) was successfully grafted with acrylamide then crosslinked by N,N′-methylene-bisacrylamide to produce biodegradable superabsorbent polymers using this reactor.

Various edible starch films were prepared via extrusion, with a particular focus on the effects of the amylose content of starches from the same resource (corn) on film processibility and performances. Four corn starches with different amylose contents (4.3-77.4%) were used as model materials. The effects of various extrusion processing conditions, such as temperature, screw speed, feeding rate, and water content were systematically investigated. It was found that, while a higher amylose content increased the difficulty of extrusion processing, this could be overcome by increasing the processing temperature, moisture content, and equilibration time. On the other hand, mechanical testing, differential scanning calorimetry, dynamic mechanical analysis, and microscopy showed that films based on higher amylose starch had better mechanical and thermal properties. The reasons include not only the easy entanglement of long linear amylose chains, but also the retained granular structure in high-amylose films, which may act as self-reinforcement.

Hydrated polysaccharides and their assemblies are known to modulate gastric emptying rate due to their capacity to change the structural and rheological properties of gastric contents (digesta). In the present study, we investigated the rheological and microstructural properties of gastric digesta from pigs fed with diets incorporating mango powder or pectin, and compared results with those from hydrated diets of the same water content, in order to investigate the origins for rheological changes in the pig stomach. All of the hydrated diets and gastric digesta were particle-dominated suspensions, generally showing weak gel or more solid-like behavior with the storage modulus (G') always greater than loss modulus (G") under small deformation oscillatory measurements, and with small deformation viscosity greater than steady shear viscosity (i.e. non-Cox-Merz superposition). Although significant rheological differences were observed between the hydrated diets, rheological parameters for gastric digesta were similar for all diets, indicative of a rheological homeostasis in the pig stomach. Whilst the addition of gastric mucin (20mg/mL) to control and mango diets altered the rheology to match the gastric digesta rheology, the effect of mucin on the pectin-containing diet was negligible. The viscous effect of pectin also hindered the action of alpha amylase as observed from relatively less damaged starch granules in pectin digesta compared to mango and control digesta. Based on the experimental findings that the rheology of gastric digesta differs from hydrated diets of the same water content, the current study revealed composition-dependent complex behavior of gastric digesta in vivo, suggesting that the rheology of food products or ingredients may not necessarily reflect the rheological effect when ingested.

Various polylactic acid (PLA)/cornstarch blends, with and without the compatibilizer methylenediphenyl diisocyanate (MDI), were prepared by melt processing using a twin-screw extruder. In the blends where it was included, MDI was distributed in either the PLA or starch phase through controlling processes conditions. The effects of MDI inclusion and its distribution on the resultant microstructures, mechanical properties, and thermal and rheological behaviors of the blends were studied via scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, mechanical testing, and Haake rheometer. The results showed that when the MDI was distributed in the starch phase before blending with PLA, the highly reactive isocyanate groups in the MDI were most probably consumed by water, resulting in an overall weakening of its compatibilizing effect. However, when the MDI was distributed in the PLA phase before blending with starch, modulus, yield strength, and impact strength were all increased. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The theological properties of corn starches with different amylose/amylopectin ratios (80/20, 50/50, 23/77, and 0/100) were systematically studied by Haake rheometry. The starches were initially pre-compounded with water to designated moisture content levels using a twin-screw extruder. A single-screw extruder with a slit capillary die was then used to characterize the shear stress and melt viscosity characteristics of sample pellets, as a function of both moisture content (19-27%) and extrusion temperature (110-140 degrees C). The melts exhibited shear thinning behavior under all conditions, with the power law index (0 < n < 1) increasing with increasing temperature and moisture content in the majority of cases. The higher the amylose content, the higher is the viscosity (for example, eta increases from 277 Pa s to 1254 Pa s when amylose content increases from 0% to 80% under a certain condition), which is opposite to the sequence of molecular weight; amylopectin-rich starches exhibited increased Newtonian behavior. These theological behaviors are attributed to the higher gelatinization temperature of amylose-rich starches, and in particular the multiphase transitions that occur in these starches at higher temperatures, and the gel-ball structure of gelatinized amylopectin. (C) 2009 Elsevier Ltd. All rights reserved.

Two types of polylactic acid (PLA) films (one amorphous and one semi-crystalline) were produced by sheet extrusion. Talc was used as a nucleation agent for the semi-crystalline PLA. The films were annealed above their T-g or were uniaxially orientated in two ways: (1) via a drawing system in front of the extruder and die or (2) via a three-roller stretching system. The slower crystallization rate and lower melting stress of the PLA resulted in amorphous film using the drawing system. Annealing above T-g increased crystallinity and polymer chain relaxation, which resulted in increases in both strength and toughness. Stretching above T-g also produced simultaneous crystallization and chain relaxation, which resulted in increases in both modulus and toughness. Both modulus and tensile strength in the stretching direction were higher than in the crosswise direction. Talc acted not only as a rigid filler to reinforce the PLA, but also as a nucleation agent for the PLA, especially during annealing.

The main defect of traditional filtering based image dehazing approaches is huge time consuming, especially for large size image haze removal. In the work, a serial of practical computation acceleration strategies for bilateral filtering based haze removal are proposed. Our approach strength lies in its wide practicability: better dehazing with very fast computation speed even for large size images. Since our approach requires less time consuming corresponding to less CPU load, it will be promising for some real time application, such as smart TV image enhancement.

This paper presents a review of the principle and technologies in reactive extrusion and their application in starch modification and preparation of starch derivatives, such as starch graft copolymers, glycosides, cationic starch, or oxidized starch. The applications of reactive extrusion in producing other biopolymers are also touched. Flexibility and efficiency of reactive extruders as reactors for biopolymers are particularly noteworthy.

This article reviews the development of studying starch gelatinization under shear and shearless conditions, in particular the technologies used to detect the degree of gelatinization. Advantages and disadvantages of each technology were discussed and then some examples were presented to demonstrate their application. A new technology RheoScope, an instrument that can measure viscosity under shear stress and simultaneously observes variation of starch particles using a microscope, was also introduced. It was found the definition of "gelatinization" could be different for different detection technologies. Under shearless condition full gelatinization of starch needs about ratio of water 3/starch 1, while the gelatinization under shear condition requires less water content since shear stress enhances the processing. The number of endotherm and enthalpy of gelatinization depends on amylose/amylopectin, moisture and lipid content.

The thermal behaviour of high amylose cornstarches (80% amylose content) was studied by DSC using high pressure stainless steel pans in the temperature range between 0-350 °C. The number of endotherms and the enthalpy of gelatinization were found to depend on moisture content. Up to four endotherms and one exotherm were determined when the moisture content was above 40%. The meaning of each endotherm has been discussed. The enthalpy of gelatinization was calculated based on the summation of all the gelatinization endotherms and found to increase with increasing water content.

Z66 antigen-positive strains of Salmonella enterica serovar Typhi change flagellin expression in only one direction from the z66 antigen to the d or j antigen, which is different from the phase variation of S. enterica serovar Typhimurium. In the present study, we identified a new flagellin gene in z66 antigen-positive strains of S. enterica serovar Typhi. The genomic structure of the region containing this new flagellin gene was similar to that of fljBA operon of biphasic S. enterica serovars. A fljA-like gene was present downstream of the new flagellin gene. A rho-independent terminator was located between the new flagellin gene and the fljA-like gene. Hin-like gene was not present upstream of the new flagellin gene. We generated a mutant strain of S. enterica serovar Typhi, which carries a deletion of the new flagellin gene. Western blotting revealed that the 51-kDa z66 antigen protein was absent from the population of proteins secreted by the mutant strain. Southern hybridization demonstrated that the z66 antigen-positive strains of S. enterica serovar Typhi carried the new flagellin gene and fliC on two different genomic EcoRI fragments. When z66 antigen-positive strains were incubated with anti-z66 antiserum, the flagellin expression by S. enterica serovar Typhi changed from z66 antigen to j antigen. The new flagellin gene and the fljA-like gene were absent in the strain with altered flagellin expression. These results suggested that the new flagellin gene is a fljB-like gene, which encodes the z66 antigen of S. enterica serovar Typhi, and that deletion of fljBA-like operon may explain why S. enterica serovar Typhi alters the flagellin expression in only one direction from the z66 antigen to the d or j antigen.