Oxidative stress defines a condition in which the prooxidant–antioxidant balance in the cell is disturbed, resulting in DNA hydroxylation, protein denaturation, lipid peroxidation, and apoptosis, ultimately compromising cells’ viability. Probiotics have been known for many beneficial health effects, and the consumption of probiotics alone or in food shows that strain-specific probiotics can present antioxidant activity and reduce damages caused by oxidation. However, the oxidation-resistant ability of probiotics, especially the underling mechanisms, is not properly understood. In this view, there is interest to figure out the antioxidant property of probiotics and summarize the mode of action of probiotic bacteria in antioxidation. Therefore, in the present paper, the antioxidant mechanisms of probiotics have been reviewed in terms of their ability to improve the antioxidant system and their ability to decrease radical generation. Since in recent years, oxidative stress has been associated with an altered gut microbiota, the effects of probiotics on intestinal flora composition are also elaborated.
Introduction. Fundamentals of the Glassy State. Glass Formation Principles. Glass Microstructure: Phase Separation and Liquid Immiscibility. Glass Compositions and Structures. Composition-Structure-Property Relationship Principles. Density and Molar Volume. Elastic Properties and Microhardness of Glass. The Viscosity of Glass. Thermal Expansion of Glass. Heat Capacity of Glass. Thermal Conductivity and Heat Transfer in Glass. Glass Transition Range Behavior. Permeation, Diffusion and Ionic Conduction in Glass. Dielectric Properties. Electronic Conduction. Chemical Durability. Strength and Toughness. Optical Properties. Fundamentals of Inorganic Glassmaking. Appendix I: Elements of Linear Elasticity. Appendix II: Units and General Data Conversions. Subject Index.
High-strength oriented PET products were prepared via the confined drawing process. The aggregation structure changes and orientation behavior of PET with different initial crystallinities (before and after drawing) were investigated by TMDSC, WAXD, and SAXS. Combined with the three-phase structure model, the generation and evolution process of highly-ordered rigid amorphous fraction (RAF) were further confirmed. Meanwhile, the effect of drawing temperature on the structure and properties of oriented PET was systematically explored. Consequently, below the cold crystallization temperature, limited mobility of crystalline regions results in two key evolutionary behaviors of PET during drawing: the transformation of the amorphous phase into highly-ordered RAF, and stress-induced crystallization under tensile force. Additionally, the annealing temperature is another key factor influencing the microstructural evolution of semi-crystalline PET. The temperature at which the crystalline phase forms, it directly determines the mobility of the crystalline regions. The characterization results from TMDSC and X-ray techniques quantitatively analyzed the composition and variation law of the aggregation structure, providing guidance for the structure-property regulation of high-strength oriented PET.
Property testing is concerned with the design of algorithms making a sublinear number of queries to distinguish whether the input satisfies a given property or is far from having this property. A seminal paper of Alon, Krivelevich, Newman, and Szegedy in 2001 introduced property testing of formal languages: the goal is to determine whether an input word belongs to a given language, or is far from any word in that language. They constructed the first property testing algorithm for the class of all regular languages. This opened a line of work with improved complexity results and applications to streaming algorithms. In this work, we show a trichotomy result: the class of regular languages can be divided into three classes, each associated with an optimal query complexity. Our analysis yields effective characterizations for all three classes using so-called minimal blocking sequences, reasoning directly and combinatorially on automata.
Kaustav Das, Ishita Ghosh, Soumalya Chakraborty
et al.
Abstract Altering surface chemistry of functional materials is an attractive route to enable large property enhancements without sacrificing overall structural-order, appealing to diverse fields of application sciences; however, the same remains unexplored for organic crystalline materials. Herein, piezoelectricity in pharmaceutical crystals is reported to show colossal surface charges driven by mechanical fracture — where a collection of dipoles arranged in polar head-to-tail fashion generates opposite surface charges on freshly fractured faces — causing them to actuate large distances over 75 µm in milliseconds. Kelvin probe force microscopy is leveraged to show many-fold surface potential enhancement in fractured surfaces relative to the pristine crystals. Further, complementarity of the surface potentials in a pair of fractured crystal shards and asymptotic decay behaviour with time are observed. Newly formed surfaces of the pharmaceutical crystals show long-lasting charges despite their relatively lower piezo-response confirmed by bulk piezometry. To establish the generality of surface phenomena, statistical analyses (≈50 samples) of post-fracture-attraction behaviour of crystals are performed. Finally, the application of fracture-driven surface charges in industrial processes is achieved by investigating flow-property and tablet-strength of bulk pharmaceutical materials. This multiscale approach unveils the symmetry-dependency of surface charges in fractured materials, and probes the same for utilisation in bulk-property engineering.
Sahana Balasubramanya, Georgia Burkhalter, Rachel Niebler
et al.
A group has Property $\mathrm{(NL)}$ if it does not admit a loxodromic element in any hyperbolic action. In other words, a group with this property is inaccessible for study from the perspective of hyperbolic actions. This property was introduced by Balasubramanya, Fournier-Facio and Genevois, who initiated the study of this property. We expand on this research by studying Property $\mathrm{(NL)}$ in Coxeter groups, a class of groups that are defined by an underlying graph. One of our main results show that a right-angled Coxeter group (RACG) has Property $\mathrm{(NL)}$ if and only if its defining graph is complete. We then move beyond the right-angled case to show that if a defining graph is disconnected, its corresponding Coxeter group does not have Property $\mathrm{(NL)}$. Lastly, we classify which triangle groups (Coxeter groups with three generators) have Property $\mathrm{(NL)}$.
In 1953, Grothendieck introduced and studied the Dunford--Pettis property (the $DP$ property) and the strict Dunford--Pettis property (the strict $DP$ property). The $DP$ property of order $p\in[1,\infty]$ for Banach spaces was introduced by Castillo and Sanchez in 1993. Being motivated by these notions, for $p,q\in[1,\infty]$, we define the strict Dunford--Pettis property of order $p$ (the strict $DP_p$ property) and the sequential Dunford--Pettis property of order $(p,q)$ (the sequential $DP_{(p,q)}$ property). We show that a locally convex space (lcs) $E$ has the $DP$ property iff the space $E$ endowed with the Grothendieck topology $τ_{Σ'}$ has the weak Glicksberg property, and $E$ has the strict $DP_p$ property iff the space $(E,τ_{Σ'}) $ has the $p$-Schur property. We also characterize lcs with the sequential $DP_{(p,q)}$ property. Some permanent properties and relationships between Dunford--Pettis type properties are studied. Numerous (counter)examples are given. In particular, we give the first example of an lcs with the strict $DP$ property but without the $DP$ property and show that the completion of even normed spaces with the $DP$ property may not have the $DP$ property.
Sepehr Sadoughi, Nikolay Yakovets, George Fletcher
The ISO standard Property Graph model has become increasingly popular for representing complex, interconnected data. However, it lacks native support for querying metadata and reification, which limits its abilities to deal with the demands of modern applications. We introduce the vision of Meta-Property Graphs, a backwards compatible extension of the property graph model addressing these limitations. Our approach enables first-class treatment of labels and properties as queryable objects and supports reification of substructures in a graph. We propose MetaGPML, a backwards compatible extension of the Graph Pattern Matching Language forming the core of the ISO standard GQL, to query these enhanced graphs. We demonstrate how these foundations pave the way for advanced data analytics and governance tasks that are challenging or impossible with current property graph systems.
A well-known result of R. Pol states that a Banach space $X$ has property ($\mathcal{C}$) of Corson if and only if every point in the weak*-closure of any convex set $C \subseteq B_{X^*}$ is actually in the weak*-closure of a countable subset of $C$. Nevertheless, it is an open problem whether this is in turn equivalent to the countable tightness of $B_{X^*}$ with respect to the weak*-topology. Frankiewicz, Plebanek and Ryll-Nardzewski provided an affirmative answer under $\mathrm{MA}+\neg \mathrm{CH}$ for the class of $\mathcal{C}(K)$-spaces. In this article we provide a partial extension of this latter result by showing that under the Proper Forcing Axiom ($\mathrm{PFA}$) the following conditions are equivalent for an arbitrary Banach space $X$: 1) $X$ has property $\mathcal{E}'$; 2) $X$ has weak*-sequential dual ball; 3) $X$ has property ($\mathcal{C}$) of Corson; 4) $(B_{X^*},w^\ast)$ has countable tightness. This provides a partial extension of a former result of Arhangel'skii. In addition, we show that every Banach space with property $\mathcal{E}'$ has weak*-convex block compact dual ball.
In this article, we study the Daugavet property and the diametral diameter two properties in complex Banach spaces. The characterizations for both Daugavet and $Δ$-points are revisited in the context of complex Banach spaces. We also provide relationships between some variants of alternative convexity and smoothness, nonsquareness, and the Daugavet property. As a consequence, every strongly locally uniformly alternatively convex or smooth (sluacs) Banach space does not contain $Δ$-points from the fact that such spaces are locally uniformly nonsquare. We also study the convex diametral local diameter two property (convex-DLD2P) and the polynomial Daugavet property in the vector-valued function space $A(K, X)$. From an explicit computation of the polynomial Daugavetian index of $A(K, X)$, we show that the space $A(K, X)$ has the polynomial Daugavet property if and only if either the base algebra $A$ or the range space $X$ has the polynomial Daugavet property. Consequently, we obtain that the polynomial Daugavet property, the Daugavet property, the diameteral diameter two properties, and the property ($\mathcal{D}$) are equivalent for infinite-dimensional uniform algebras.
Fossil fuel and conventional lubricant are not environmentally friendly, non-biodegradable, toxic, and non-renewable. Therefore, the objective of this paper is to evaluate the thermal and fluidity of the biolubricant synthesized from Mango (Mangifera indica L.) kernel oil (MKO) blended with cold flow property improvers using standard techniques. A twostep process of esterification and transesterification was employed to produce fatty acid methyl ester (FAME) from MKO mentioned as Mango kernel methyl ester (MKME). Double transesterification of the MKME with trimethylolpropane (TMP) in the presence of sodium methoxide yielded 95 % Mango oil based trimethylolpropane ester (MOTE). Anotherof the MKME was used to synthesize biolubricant using the conventional epoxidation which yielded 70 % Mango oil based epoxidised biolubricant (MEB-L). A simultaneous SDT 2960 TG/DTA from TA instrument analysis reveals MOTE to present higher thermal stability (302 °C) with 5 % weight loss compared to MEB-L (250.5 °C) with similar 5 % weight loss. Degradation was endothermic for both MOTE and MEB-L and predominantly followed a single step of weight lost. Degradation becomes rapid at temperature above 300 °C for MOTE while for MEB-L degradation started at temperature above 250 °C. At about the temperature range of 850 - 900 °C, 95 % of MEB-L and 77 % of MOTE were lost respectively. The relative thermal stability of MOTE would be attributed to the alcohol substitution of the branch chain Trimethylolpropane (TMP) resulting into a more thermally stable Triester (MOTE). The results of the analysis of the cold flow properties reveal that various blend of MEB-L with n-BE portrays better pour and cloud point as they are lower than their counterpart (blends of MOTE with n-BE) and (blends of even MOTE & MEB-L with EAA for both cloud/pour points).
Abstract To predict the mechanical properties of wood in the transverse direction, this study used machine learning to extract the anatomical features of wood from cross-sectional stereograms. Specimens with different orientations of the ray parenchyma cell were prepared, and their modulus of elasticity (MOE) and modulus of rupture (MOR) were measured by a three-point bending test. The orientation of the ray parenchyma cell and wood density ( $$\rho $$ ρ ) were used as parameters for the MOE and MOR prediction. Conventional machine learning algorithms and artificial neural network were used, and satisfactory results were obtained in both cases. A regular convolutional neural network (CNN) and a density-informed CNN were used to automatically extract anatomical features from the specimens’ cross-sectional stereograms to predict the mechanical properties. The regular CNN achieved acceptable but relatively low accuracy in both the MOE and MOR prediction. The reason for this may be that $$\rho $$ ρ information could not be satisfactorily extracted from the images, because the images represented a limited region of the specimen. For the density-informed CNN, the average prediction coefficient for both the MOE and MOR drastically increased when $$\rho $$ ρ information was provided. A regression activation map was constructed to understand the representative anatomical features that are strongly related to the prediction of mechanical properties. For the regular CNN, the latewood region was highly activated in both the MOE and MOR prediction. It is believed that the ratio and orientation of latewood were successfully extracted for the prediction of the considered mechanical properties. For the density-informed CNN, the activated region is different. The earlywood region was activated in the MOE prediction, while the transition region between the earlywood and latewood was activated in the MOR prediction. These results may provide new insights into the relationship between the anatomical features and mechanical properties of wood.
Jassica S. L. Leu, Jasy J. X. Teoh, Angel L. Q. Ling
et al.
Due to their distinctive structural features, lyotropic nonlamellar liquid crystalline nanoparticles (LCNPs), such as cubosomes and hexosomes, are considered effective drug delivery systems. Cubosomes have a lipid bilayer that makes a membrane lattice with two water channels that are intertwined. Hexosomes are inverse hexagonal phases made of an infinite number of hexagonal lattices that are tightly connected with water channels. These nanostructures are often stabilized by surfactants. The structure’s membrane has a much larger surface area than that of other lipid nanoparticles, which makes it possible to load therapeutic molecules. In addition, the composition of mesophases can be modified by pore diameters, thus influencing drug release. Much research has been conducted in recent years to improve their preparation and characterization, as well as to control drug release and improve the efficacy of loaded bioactive chemicals. This article reviews current advances in LCNP technology that permit their application, as well as design ideas for revolutionary biomedical applications. Furthermore, we have provided a summary of the application of LCNPs based on the administration routes, including the pharmacokinetic modulation property.
Previous experimental studies have demonstrated that the recrystallization in nuclear materials is very sensitive to the annealing temperature, dislocation density, and original grain morphology. However, the synergistic effect of these intrinsic and extrinsic factors on recrystallization has been rarely studied due to the elevated temperatures of recrystallization and the costliness of experiments, especially in tungsten (W). In the present work, we have developed an approach that combines a phase-field model with the physics-based classical nucleation theory to study the synergistic impact of these factors on the recrystallization process. We systematically investigate the synergistic effect of annealing temperature, dislocation density, and original grain morphology on the recrystallization rate and the average recrystallized grain size. The simulation results show that increasing the dislocation density and the annealing temperature can effectively reduce the average grain size after full recrystallization. For an annealing temperature above 1523 K, the recrystallization rates have minor changes with increasing the dislocation density and annealing temperature. Furthermore, we employ an empirical model to quantitatively calculate the Vickers hardness of deformed W during the recrystallization process based on the phase-field microstructures. Notably, columnar grain crystals are found to be more effective in reducing irradiation hardness than isometric grain crystals. We believe that these simulations can provide a valuable reference for the preparation and design of radiation-resistant W materials.
Phase transition is a central topic in condensed matter physics, all the time. In this paper, as a general representative of phase transition, the Cu crystallization is discussed. And some physical quantities is defined to quantificationally describe the structure property in Cu crystallization, such as diffusion property and symmetry so on. As a result, it is indicated that there are some interesting changes of structure property in Cu crystallization.
Aili Amupolo, Sofia Nambundunga, Daniel S. P. Chowdhury
et al.
This paper examines different off-grid renewable energy-based electrification schemes for an informal settlement in Windhoek, Namibia. It presents a techno-economic comparison between the deployment of solar home systems to each residence and the supplying power from either a centralized roof-mounted or ground-mounted hybrid microgrid. The objective is to find a feasible energy system that satisfies technical and user constraints at a minimum levelized cost of energy (LCOE) and net present cost (NPC). Sensitivity analyses are performed on the ground-mounted microgrid to evaluate the impact of varying diesel fuel price, load demand, and solar photovoltaic module cost on system costs. HOMER Pro software is used for system sizing and optimization. The results show that a hybrid system comprising a solar photovoltaic, a diesel generator, and batteries offers the lowest NPC and LCOE for both electrification schemes. The LCOE for the smallest residential load of 1.7 kWh/day and the largest microgrid load of 5.5 MWh/day is USD 0.443/kWh and USD 0.380/kWh, respectively. Respective NPCs are USD 4738 and USD 90.8 million. A sensitivity analysis reveals that variation in the fuel price and load demand changes linearly with system costs and capacities. However, reducing the PV module price in an energy system that includes wind and diesel power sources does not offer significant benefits. Furthermore, deploying an energy system that relies on fossil fuels to each residence in an informal settlement is not environmentally responsible. Unintended negative environmental impacts may result from the mass and simultaneous use of diesel generators. Therefore, a microgrid is recommended for its ability to control the dispatch of diesel generation, and its scalability, reliability of supply, and property security. A roof-mounted microgrid can be considered for piloting due to its lower initial investment. The electricity tariff also needs to be subsidized to make it affordable to end-users. Equally, government and community involvement should be prioritized to achieve long-term economic sustainability of the microgrid.