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The material performance simulation software JMatPro was used to simulate and calculate equilibrium phase structure and properties of a mixture formed by mixing different proportions of Norem02 alloy and F304 stainless steel. The results show that in the range of 500-1300 °C, equilibrium phases of the mixture include Austenite and Ferrite, and the carbides include M2(C,N), M6C, M7C3 and M23C6. As the content of F304 in the mixture increases, the phase transition temperature A1 of the mixture decreases, and A3 first decreases and then increases; in the equilibrium phase, the content of Austenite and Ferrite increases, and the content of carbide decreases until the carbides M7C3 and M6C gradually disappear. Density, coefficient of linear expansion, thermal conductivity, Young's modulus, Poisson's ratio and specific heat capacity of different mixture materials vary with temperature in a complex manner. Strength and hardness of the mixture formed when the content of F304 is 20 % is the highest. The finer the grain size of the mixture, the higher the strength and hardness of the material. Comparing standard physical property data of F304 stainless steel at room temperature with the simulation calculation results, it is found that the error is small, which verifies the accuracy of the simulation calculation results. [ABSTRACT FROM AUTHOR]

When it comes to improving cancer therapies, one challenge is to identify key biological parameters that prevent immune escape and maintain an equilibrium state characterized by a stable subclinical tumor mass, controlled by the immune cells. Based on a space and size structured partial differential equation model, we developed numerical methods that allow us to predict the shape of the equilibrium at low cost, without running simulations of the initial-boundary value problem. In turn, the computation of the equilibrium state allowed us to apply global sensitivity analysis methods that assess which and how parameters influence the residual tumor mass. This analysis reveals that the elimination rate of tumor cells by immune cells far exceeds the influence of the other parameters on the equilibrium size of the tumor. Moreover, combining parameters that sustain and strengthen the antitumor immune response also proves more efficient at maintaining the tumor in a long-lasting equilibrium state. Applied to the biological parameters that define each type of cancer, such numerical investigations can provide hints for the design and optimization of cancer treatments. [ABSTRACT FROM AUTHOR]

When it comes to improving cancer therapies, one challenge is to identify key biological parameters that prevent immune escape and maintain an equilibrium state characterized by a stable subclinical tumor mass, controlled by the immune cells. Based on a space and size structured partial differential equation model, we developed numerical methods that allow us to predict the shape of the equilibrium at low cost, without running simulations of the initial-boundary value problem. In turn, the computation of the equilibrium state allowed us to apply global sensitivity analysis methods that assess which and how parameters influence the residual tumor mass. This analysis reveals that the elimination rate of tumor cells by immune cells far exceeds the influence of the other parameters on the equilibrium size of the tumor. Moreover, combining parameters that sustain and strengthen the antitumor immune response also proves more efficient at maintaining the tumor in a long-lasting equilibrium state. Applied to the biological parameters that define each type of cancer, such numerical investigations can provide hints for the design and optimization of cancer treatments.

The mechanism governing the deoxidation of vanadium metal is regarded as fundamental knowledge; however, it has not been elucidated in existing literature. In this paper, the thermodynamic data of V-H-O systems were summarized, and the Gibbs free energies of the main compounds were calculated. Consequently, the deoxidation limits of different reductants in a V-O system were evaluated, namely: Si, Al, and Mg. It was observed that Si cannot remove an O content of less than 7.27 wt% from V. However, Al was the stronger reducing agent; it could remove O contents of up to 0.01 and 0.1 wt% at 800 and 1050 °C, respectively. Nevertheless, Mg exhibited the best reducing properties as it could remove less than 0.01 wt% of O at 1100 °C. The addition of H2 renders the V-O solid solution unstable to a certain extent, thereby indicating that H2 facilitates deoxygenation. Furthermore, the results obtained by analyzing the equilibrium conditions were in accordance with the results of the deoxidation limit in the V-O system. In other words, this study demonstrates that the oxygen in vanadium can be effectively controlled by changing the reductant dosage and temperature.

This study characterized steady state events (SS) in a semiarid reservoir (Brazil) dominated by cyanobacteria for 130 weeks, and evaluated the influence of different abiotic variables on their occurrence. It was hypothesized that, in semiarid reservoirs, steady state events are independent from seasonality and influenced by high nutrient concentrations, and steady state periods show low variation of species. Our data revealed the occurrence of SS events in both the dry and wet seasons. Higher concentrations of nitrate and sodium together with higher values of color favored the development of SS. Species composing the SS dominated by Microcystis aeruginosa (Kützing) Kützing was correlated with higher sulfate concentrations, while higher values of turbidity and sodium concentrations favored the SS of Cylindrospermopsis raciborskii (Woloszynska) Seenaya and Suba Raju and Planktothrix agardhii (Gomont) Anagnostidis and Komárek. The results supported the hypothesis and showed the importance of variables rarely evaluated in works of this nature, such as sodium and sulfate in SS establishment of cyanobacteria.

Purpose: To assess whether extracellular volume fraction (ECV) calculated from iodine(-blood) density images (I-B) of dual-energy liver CT (DECT) equilibrium phase data (EqD) is useful in estimating the degree of liver fibrosis.Materials and Methods: Consecutive 52 patients with chronic liver disease who underwent fast kV switching DECT and liver MR elastography (MRE) were retrospectively enrolled. Iodine(-water) density images (I-W) and I-B generated from EqD and ECV were calculated. As blood pools, abdominal aorta (Ao) and suprahepatic inferior vena cava (IVC) were chosen, and, therefore, 4 types of ECV (ECVI-W Ao, ECVI-W IVC, ECVI-B Ao, ECVI-B IVC) were obtained. ECV was also calculated using conventional method (ECVconv Ao). The correlation coefficients (R2 or rho) of these five ECVs versus liver stiffness (MRE) or pathologically proven fibrosis grades were compared.Results: As for correlation with liver stiffness, R2 for ECVconv.Ao, ECVI-W Ao, ECVI-B Ao, ECVI-W IVC, and ECVI-B IVC, were 0.26, 0.34, 0.44, 0.39, and 0.52, respectively (all p < 0.0001). Histopathological correlation was available in 28 patients, and rho values were 0.61, 0.60, 0.71, 0.68, and 0.76, respectively (all p < 0.001).Conclusion: ECVI-B IVC calculated from EqD of DECT is useful in estimating the degree of liver fibrosis. [ABSTRACT FROM AUTHOR]

The metastable alloy materials including crystalline metastable, microcrystallme metastable, quasi- crystal metastable. and metallic glass have great influences on the field of materials science. They are different from ordinary metal materials. For example, the crystalline metastable phase has good corrosion resistance, the microcrystallme metastable phase has high strength and hardness due to fine gram, and the metallic glass which is an amorphous alloy has many characters such as uniform internal structure. The metallic glass has no defects or magnetic anisotropy, thus exhibiting high strength and low coercivity. Because of the excellent properties of these metastable alloy materials, a research wave has been created m the field of materials science. In the decades, many methods for the preparation of metastable phases have been obtained through extensive practice and testing. For example, the metastable phase is obtained by controlling the solidification process, but the preparation process is complicated and needs further optimization. Through the accumulation method, metal glass and amorphous film can be prepared, which greatly improves the corrosion resistance of the material. Through these methods, a metastable phase is prepared that can greatly improve the material's properties. In order to improve the preparation system of the metastable phase, further explorations are still needed. However, the metastable phase, which will have a negative impact on the material, must be transformed and eliminated. The basic concept and formation mechanism of metastable phases were introduced m the present paper. The possibility that metastable phase could be stable under certain conditions was proved according to the theory dynamics and thermodynamics. The classification, formation mechanism and preparation techniques of metastable phases m alloy materials were systematically summarized. Different kinds of metastable materials would have different effects. Therefore, the elimination method of the negative metastable phase was demonstrated m the present paper, and the improvement of material properties due to the elimination of the metastable phase was also explained. Moreover, the preparation methods of the metastable phase which could improve the material properties were focused on this paper. Finally, the future research points and development trends of metastable phases were forecasted. [ABSTRACT FROM AUTHOR]

This study characterized steady state events (SS) in a semiarid reservoir (Brazil) dominated by cyanobacteria for 130 weeks, and evaluated the influence of different abiotic variables on their occurrence. It was hypothesized that, in semiarid reservoirs, steady state events are independent from seasonality and influenced by high nutrient concentrations, and steady state periods show low variation of species. Our data revealed the occurrence of SS events in both the dry and wet seasons. Higher concentrations of nitrate and sodium together with higher values of color favored the development of SS. Species composing the SS dominated by Microcystis aeruginosa (Kützing) Kützing was correlated with higher sulfate concentrations, while higher values of turbidity and sodium concentrations favored the SS of Cylindrospermopsis raciborskii (Woloszynska) Seenaya and Suba Raju and Planktothrix agardhii (Gomont) Anagnostidis and Komárek. The results supported the hypothesis and showed the importance of variables rarely evaluated in works of this nature, such as sodium and sulfate in SS establishment of cyanobacteria. [ABSTRACT FROM AUTHOR]

Objectives: To assess whether extracellular volume fraction (ECV) obtained from routine liver CT equilibrium phase data utilizing new subtraction algorithm is useful in estimating the degree of liver fibrosis.Materials and Methods: Consecutive 41 patients, 21 men and 20 women, with chronic liver diseases who underwent quadri-phase liver CT and MR elastography within 3 months were retrospectively enrolled. Subtraction image of unenhanced from equilibrium phase (240 s) images using conventional and new algorithms were made. We firstly assessed the quality of these subtraction algorithms using patients in whom anatomical misregistration between the two image sets were prominent. Then, ECVs were calculated using both subtraction data sets (ECV-convSub, and ECV-newSub, respectively). ECV were also calculated by traditional manual method (ECV-man). Correlation coefficients of 3 types of ECV were compared using liver stiffness (kPa) as measured by MR elastography and pathologically proven fibrosis grades as reference standards.Results: For eleven patients with prominent anatomical misregistration between the unenhanced and equilibrium phases, new algorithm provided significantly better subtraction images than the conventional one (p = 0.001, Wilcoxon's signed rank test). As for correlation with liver stiffness, R2 for ECV-man, ECV-convSub, and ECV-newSub, were 0.57, 0.59, and 0.66, respectively (all p < 0.0001, Pearson's correlation). Histological assessment for fibrosis grades were available in 20 patients, and rho values for these three ECVs were 0.66, 0.61, and 0.71, respectively (all p < 0.01, Spearman's rank correlation).Conclusion: ECV-newSub showed better correlation to liver stiffness and pathological fibrosis grades than ECV-convSub and ECV-man, which could be a reliable biomarker of liver fibrosis obtained from routine clinical diagnostic imaging data, where equilibrium phase delay time was set at 240 s. [ABSTRACT FROM AUTHOR]

Dissolution of cement clinker minerals involves a number of physical and chemical processes, and the simulation of dissolution processes helps to understand cement hydration conveniently. Dissolution model of cement clinker minerals was set up based on simulation theory of geochemical reaction equilibrium, PHREEQC simulation software provided by United States Geological Survey (USGS) was employed for thermodynamic calculation of C-S-H system. Stability of C-S-H system with low Ca/Si ratio at normal temperature was also explored. The results show that many phase assemblages coexist with the aqueous phase depending on its composition. The most stable product varies with different Ca/Si ratio of C-S-H system. Active SiO will consume excessive CH, so the Ca/Si ratios of C-S-H system decrease, C-S-H with low Ca/Si ratio becomes the most stable product, and this is the thermodynamic driving force of secondary pozzolanic reaction. [ABSTRACT FROM AUTHOR]

Phytoplankton species composition, seasonal dynamics, and spatial distribution were studied during 2009 along with key physical and chemical variables in Yanghe Reser-voir, a temperate eutrophic reservoir with a long water residence time of 284 days. In the northern part of the reservoir, Microcystis wesenbergii dominated throughout the summer but no steady-state phases were found, as periods of equilibrium lasted for only two weeks each. In the southern part, the first steady-state phase occurred in spring, lasted for four weeks, and was dominated by Cryptomonas erosa. The second phase was dominated by M. wesenbergii in late summer and persisted for four weeks. The results suggest that steady-state phases establish more readily in deep areas with longer residence times and more dominant species compared to shallow areas. Ther-mal stratification in the deep area and fluctuation of nitrogen and phosphorus concen-trations in the shallow area were considered to be responsible for such differences. Canonical correspondence analysis indicated that M. wesenbergii was more strongly related to NOx-N than to temperature in both areas of the reservoir. We conclude that in eutrophic lakes, a high concentration of nutrients such as NOx-N is more important than temperature in the establishment of a steady state. [ABSTRACT FROM AUTHOR]

Phase equilibria of the Na,K,Mg,Na,K,Mg,Ca//SO,Cl-HO system are studied at 50°C via translation in the crystallization range of glaserite (3KSO · NaSO). It is found that glaserite as the equilibrium phase of the investigated system at 50°C participates in the formation of 21 invariant points, 21 monovariant curves, and 34 divariant fields. A fragment of the phase equilibria diagram of the investigated system is constructed in the crystallization range of glaserite. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: The aim of this study is to investigate whether subserosal enhancement on the delayed-phase dynamic magnetic resonance (MR) study (SED) can differentiate T2 from T1 gallbladder carcinoma (GBC). Methods: The institutional research board approved this retrospective study. Between 1997 and 2006, there were surgically proven 11 T1 and 21 T2 GBC in 30 patients, all of whom had undergone preoperative contrast enhanced dynamic MR study, either with a 2D sequence (n=17) or 3D sequences (n=15). All images were reviewed by two radiologists for the presence of SED, and receiver operating characteristic (ROC) curve analysis was performed. Sensitivity, specificity, positive and negative predictive values were calculated by consensus. Results: The areas under the ROC curves of the two readers were 0.91 and 0.86, and the kappa value was 0.78. Of the 21 T2 GBC, 18 and 3 showed positive and negative SED, respectively. Of the 11 T1 GBC, 1 and 10 showed positive and negative SED, respectively. The sensitivity, specificity, positive and negative predictive values of SED for diagnosing T2 lesions were 86%, 88%, 91% and 77%, respectively. Conclusions: In conclusion, SED may be a useful sign to differentiate T2 from T1 GBC, which would affect the preoperative surgical planning of the patients. [Copyright &y& Elsevier]

Based on the phase field theory, the phase precipitation sequence of NiAlCr alloy and the free energy of each phase were studied. Moreover, the interatomic potentials of L1 phase, L1 phase and DO phase changing with temperature and concentrations were computed through utilizing the interatomic potentials equations induced by Khachaturyan's relational equations between the interatomic potentials and the long-range order (LRO) parameters. Results match preceding work and demonstrate that the phase precipitation sequence of NiAlCr alloy is the disordered phase → L1 pre-precipitation phase → L1 equilibrium phase → L1+DO equilibrium phase. Free energies of L1 pre-precipitation phase are higher and interatomic potentials are smaller than those of L1 equilibrium phase; therefore, it is concluded that L1 phase is unstable, and phase transformation would occur to L1 which is more stable; L1 phase precipitates earlier than DO phase because L1's interaction potentials are larger than DO's. [ABSTRACT FROM AUTHOR]

Abstract: The phase transformations of FeCoNiCrCu0.5 alloy with the as-cast structure and heat-treated structures were studied. The as-cast alloy specimens were first heated at 1050°C with a holding time of 1h. Serial heat-treatment processes at 350°C, 500°C, 650°C, 800°C, 950°C, 1100°C, 1250°C and 1350°C with a holding time of 24h were then carried out to understand the phase evolution and the relationship between the microstructure and the hardness of the specimens. The microstructures were investigated and chemical analyses performed by optical microscopy (OM), scanning elector microscopy (SEM), X-ray diffractometer (XRD) and transmission elector microscopy (TEM). The results show that FCC peaks were observed from the X-ray diffraction of the as-cast specimens and a precipitate phase was present in the specimens that had been heated to 950°C. The hardness of the FeCoNiCrCu0.5 alloy remained unchanged in the specimens that underwent various heat treatments that were applied in this study. [Copyright &y& Elsevier]

1. Equilibrium and non-equilibrium hypotheses have often been used to explain observations in community ecology. Published case studies have demonstrated that steady state phytoplankton assemblages are more likely to occur in deep lakes than in shallow mixed ones. 2. Phytoplankton seasonal succession was studied by weekly sampling in Faxinal Reservoir (S Brazil), a subtropical deep, clear, warm monomictic and slightly eutrophic reservoir. This study demonstrated an alternation of steady and non-steady state phases of phytoplankton assemblages with different dominant species during the steady states. 3. During the studied period, three steady states were identified with different dominant algal species: Anabaena crassa (Cyanobacteria), Nephrocytium sp. (green algae) and Asterionella (diatoms). 4. Each steady state in Faxinal Reservoir developed under stratified conditions of the water column according to the predictions of the disturbance concepts. Apparently, the major forces driving the development and persistence of these steady-state phases were closely related to thermal stratification and its consequences. 5. This study is the first report on development of more than one steady state within a year in a stratified water body. The development of three steady states might be the result of the relatively long stratification period in the Faxinal Reservoir and to its unique geochemical features. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this study was three-fold; to investigate the different mechanisms of material exchange during the equilibrium phase of the granulation process and whether these mechanisms are consistent with the mechanisms described in the growth regime map, to study how material properties and process conditions affect these exchange mechanisms, and to correlate Stokes deformation number to the exchange mechanisms. Microcrystalline cellulose (MCC), α-lactose, microfine cellulose (MFC), and dextrin were granulated using water as a binding agent. Once in the equilibrium phase, 5% (w/w) of the granular mass was replaced with wet tracer granules, after which the granulation process was continued. Granules were typically of a size of approximately 1mm in diameter. Therefore, these granules can also be called pellets. Tracer experiments show indeed solid material exchange can take place in the equilibrium phase of the high shear granulation process. Tracer material was equally dispersed throughout the whole batch for all materials tested. However, the granulation time needed to reach this homogeneous distribution varied with material and granulation conditions. Three different mechanisms of material exchange were identified: exchange by disintegration, where granules are rapidly crushed and formed to granules again; exchange by deformation, where abraded granule fragments immediately fuse with other granules; and exchange by distribution, where there is a prolonged period over which both tracer and standard granules stay intact, followed by uncontrolled growth and exchange of material. It was found that it is possible to shift between the mechanisms by changing the process conditions, e.g., changing viscosity or amount of binder liquid. These observations indicate that by choosing the appropriate process conditions improved distribution of small amounts of insoluble materials in the granules can be obtained. A relation exists between the exchange mechanisms and the growth regime map: the disintegration mechanism resembles ‘crumb behaviour’, the deformation mechanism resembles ‘steady growth’, and the distribution mechanism resembles ‘nucleation’ and ‘induction growth’. Unfortunately, Stokes deformation number cannot be used as a predictive tool when low viscosity binders like water are used, due to the importance of viscosity in the equation. However, this number is one of the variables of the growth regime map. Since the exchange mechanisms correspond to the granule growth mechanisms in the regime map, alternatively colour experiments might be used to reveal the granulation regime. [Copyright &y& Elsevier]

Phytoplankton seasonal and long-term succession can be described and functionally classified by associations similar as in terrestrial vegetation studies. Such a concept has to include 'climax' into pelagic succession which in turn leads to the question to what extent steady state assemblages occur and if during periods of dynamic equilibrium can be identified. Here we explore the situation with respect to the above question for deep, nutrient poor, alpine lakes in Austria. We first track the long-term development of phytoplankton biomass, their taxonomic structure and their relation to total phosphorus and chlorophyll-a as predictors of trophic state over the past 35 years. We then analyse this data set for coherent algal associations which can be ascribed to trait separated functional groups according to Reynolds et al. (2002). A three year period of stable environmental conditions has then be extracted from the progression of trophic state indices, having similar dominating species each year. These years were finally analysed for steady state conditions according to definitions given in Sommer et al. (1993). During thermal stratification, achievement of an equilibrium could be ruled out although coexistence of several dominating species lasted for several weeks. Habitat templates were constructed from environmental variables prior to biomass peaks for two species important in summer assemblages, the dinoflagellate Ceratium hirundinella and the diatom Fragilaria crotonensis. In summary, functional groups proved to be a valid and useful concept to describe species succession of phytoplankton in deep alpine lakes while pelagic climax is much less clear and steady state conditions were never met. [ABSTRACT FROM AUTHOR]

Late summer phytoplankton associations were studied qualitatively and quantitatively in 80 Hungarian lakes altogether (mostly shallow salt lakes, reservoirs, oxbows, gravel pit lakes). Equilibrium phases sensu Sommer et al. (1993) were found only in 17 lakes. Most of them were under some kind (high salt content or very low level of nutrients) of stress factor. It is concluded that environmental stress forces phytoplankton communities towards equilibrium. No relationship between occurrence of equilibria and trophic state was found. Species number of non-equilibrated lakes was almost three times as high as those in equilibrium. Of the 31 recently described (Reynolds et al., 2002) phytoplankton assemblages most of those were recognized that are likely to occur in shallow lakes. Separation of a functional group WS from W2 for Synura dominated lakes is suggested. It seemed also necessary to raise a group (YPh) for lakes dominated by Phacotus. Sorting of Dinophyta species into different already described functional groups is desirable. [ABSTRACT FROM AUTHOR]

Purpose: To compare abdominal equilibrium phase (EP) CT images of obese and non-obese patients to identify the reconstruction method that preserves the diagnostic value of images obtained in obese patients.Methods: We compared EP images of 50 obese patients whose body mass index (BMI) exceeded 25 (group 1) with EP images of 50 non-obese patients (BMI < 25, group 2). Group 1 images were subjected to deep learning reconstruction (DLR), hybrid iterative reconstruction (hybrid-IR), and model-based IR (MBIR), group 2 images to hybrid-IR; group 2 hybrid-IR images served as the reference standard. A radiologist recorded the standard deviation of attenuation in the paraspinal muscle as the image noise. The overall image quality was assessed by 3 other radiologists; they used a confidence scale ranging from 1 (unacceptable) to 5 (excellent). Non-inferiority and potential superiority were assessed.Results: With respect to the image noise, group 1 DLR- were superior to group 2 hybrid-IR images; group 1 hybrid-IR- and MBIR images were neither superior nor non-inferior to group 2 hybrid-IR images. The quality scores of only DLR images in group 1 were superior to hybrid-IR images of group 2 while the quality scores of group 1 hybrid-IR- and MBIR images were neither superior nor non-inferior to group 2 hybrid-IR images.Conclusions: DLR preserved the quality of EP images obtained in obese patients. [ABSTRACT FROM AUTHOR]

The behavior of crystalline tetraalkylammonium salts at 290-350 K was studied by differential scanning calorimetry. For tetraethyl- and tetrabutylammonium bromides (EtNBr and BuNBr), the experimental heat capacities agreed well with the literature values. For tetrahexyl-, tetraheptyl-, and tetraoctylam-monium bromides (HexNBr, HepNBr, and OctNBr), phase transitions were found between crystal modifications whose characteristic temperatures depended significantly on the size of the cation. Empirical equations for the temperature dependences of the heat capacities of the salts within the ranges of homogeneous equilibrium phases were derived. [ABSTRACT FROM AUTHOR]

• A new size and space structured model describing early interactions between tumor cells and cytotoxic effector immune cells. • A model able to reproduce cancer persistent equilibrium phases. • Interpretation of the equilibrium by means of eigenvalue problems. • Numerical results illustrate the crucial role of space heterogeneities in the dynamics of the immune response. The recent success of immunotherapies for the treatment of cancer has highlighted the importance of the interactions between tumor and immune cells. Mathematical models of tumor growth are needed to faithfully reproduce and predict the spatiotemporal dynamics of tumor growth. We introduce a mathematical model intended to describe by means of a system of partial differential equations the early stages of the interactions between effector immune cells and tumor cells. The model is structured in size and space, and it takes into account the migration of the tumor antigen-specific cytotoxic effector cells towards the tumor micro-environment by a chemotactic mechanism. We investigate on numerical grounds the role of the key parameters of the model such as the division and growth rates of the tumor cells, and the conversion and death rates of the immune cells. Our main findings are two-fold. Firstly, the model exhibits a possible control of the tumor growth by the immune response; nevertheless, the control is not complete in the sense that the asymptotic equilibrium states keep residual tumors and activated immune cells. Secondly, space heterogeneities of the source of immune cells can significantly reduce the efficiency of the control dynamics, making patterns of remission-recurrence appear. [ABSTRACT FROM AUTHOR]