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Female Anopheles mosquitoes are the primary vectors responsible for malaria transmission. The control of malaria is essential for humankind. In this study, we introduce a nonlinear deterministic model to control malaria disease by deploying Wolbachia bacteria into the Anopheles mosquitoes. Further, we study the effect of Wolbachia on temperature variation in tropical and subtropical regions of the world. We analyze the model for its positivity and boundedness with an initial condition in a specific set so that the model is well-defined mathematically and meaningful epidemiologically. We find the malaria-free equilibrium points of the model and analyze the local stability of all the equilibrium points. We calculate the basic reproduction number by the next-generation matrix method, which shows the stability of malaria-free equilibrium. Then we explore malaria present endemic equilibrium in both cases: Wolbachia-infected and Wolbachia-free possibilities. We observe that the number of infections is less in the Wolbachia-infected equilibrium case, and we find that Wolbachia can reduce malaria transmission in all temperature conditions. The sensitivity analysis of all different parameters is also calculated. We demonstrate the optimum temperature (from 22 °C to 28 °C) by numerical simulation where the malaria exposure and transmission rate is high. We can apply the work in all subtropical and tropical regions to control malaria transmission worldwide. [ABSTRACT FROM AUTHOR]

System identification is becoming a relevant research area for numerous applications in power grids due to the increasing complexity of the system. A paradigm shift in power system infrastructure driven by renewable energy resources, controllable loads, and new power electronics technologies have given rise to new challenges in power systems operation and control. This increased complexity of power systems and unavailability of physics-based models of most inverter-based resources requires that traditional modeling of power systems approaches be complemented by system identification-based black or grey box modeling techniques. In light of the importance of system identification and little attention paid to the applications of these techniques in transforming power systems, this paper provides a comprehensive review of active probing-based system identification methods in the context of power system applications. It reviews applications of both linear and nonlinear system identification with discussion on their potential and key takeaways. To motivate a further practical use in power systems, the paper provides an example of system identification, to develop a state space model of an unknown plant with step-by-step details. The paper highlights the advantages of using modern power electronics-based sources in the identification process and discusses the emerging research directions for future. [Display omitted] • System identification has high potential in power systems applications. • System identification can overcome limits of traditional system modeling approaches. • Distributed energy resources in power grids incur challenges and opportunities. • Power electronics-based resources offer flexibility and cost effectiveness in power system identification. [ABSTRACT FROM AUTHOR]

Abstract: The mixed electronic–ionic conduction in 0.5[xAg2O–(1−x)V2O5]–0.5TeO2 glasses with x=0.1–0.8 has been investigated over a wide temperature range (70–425K). The mechanism of dc conductivity changes from predominantly electronic to ionic within the 30⩽mol% Ag2O⩽40 range; it is correlated with the underlying change in glass structure. The temperature dependence of electronic conductivity has been analyzed quantitatively to determine the applicability of various models of conduction in amorphous semiconducting glasses. At high temperature, T>θ D/2 (where θ D is the Debye temperature) the electronic dc conductivity is due to non-adiabatic small polaron hopping of electrons for 0.1⩽x⩽0.5. The density of states at Fermi level is estimated to be N(E F)≈1019–1020 eV−1 cm−3. The carrier density is of the order of 1019 cm−3, with mobility ≈2.3×10−7–8.6×10−9 cm2 V−1 s−1 at 300K. The electronic dc conductivity within the whole range of temperature is best described in terms of Triberis–Friedman percolation model. For 0.6⩽x⩽0.8, the predominantly ionic dc conductivity is described well by the Anderson–Stuart model. [Copyright &y& Elsevier]

Abstract: X-ray induced structural changes at the Ag/As2S3 interface are investigated using X-ray photoelectron spectroscopy on the samples prepared within the spectrometer. The as-prepared film consists of stable heteropolar As–S bonds as well as ∼16% S (and As) atoms in lower (higher) electron density configurations such as the –S–S– (–As–As–) segments with ‘wrong’ homopolar bonds. Two distinct stages of the X-ray induced diffusion are revealed. At first, silver reacts with atoms within –S–S– like segments to form Ag–S bonds. In the second stage, the Ag–S bonds decompose due to the reaction of S with As atoms within the –As–As– ‘wrong’ segments to form As–S heteropolar bonds, and silver diffuses away from the interface into the film. The results provide guideline for enhancing silver photodiffusion in chalcogenide glass. The irradiation of the (Ag–Te)/As2S3 sample with X-rays shows that not only Ag, but Te also diffuses away from the surface. [Copyright &y& Elsevier]

Abstract: Electronic transport in the high temperature paramagnetic regime of the colossal magnetoresistive oxides, La1−x A x MnO3, A=Ca, Sr, Ba, x≃0.1–0.3, has been investigated using resistivity measurements. The main motivation for this work is to relook into the actual magnitude of the activation energy for transport in a number of manganites and study its variation as a function of hole doping (x), average A-site cation radius (〈r A〉), cationic disorder (σ 2) and strain (ε zz ). We show that contrary to current practice, the description of a single activation energy in this phase is not entirely accurate. Our results clearly reveal a strong dependence of the activation energy on the hole doping as well as disorder. Comparing the results across different substituent species with different 〈r A〉 reveals the importance of σ 2 as a metric to qualify any analysis based on 〈r A〉. [Copyright &y& Elsevier]

The short-range atomic order around all three constituent atoms in a prototypical bulk metallic glass (BMG) system was probed in a complementary way, using extended X-ray absorption fine structure for neighborhood of the higher atomic number elements, and extended energy loss fine structure (EXELFS) for the lower atomic number ones. The PdxNi(80−x)P(20) system is a prototype for a whole class of BMG formers which are 80% transition metal and 20% metalloid. We find that the structure of these BMGs could be explained in terms of those of glasses at the end of the BMG range, namely, Pd60Ni20P20 and Pd30Ni50P20. The binary phosphide crystals near x=0 and 80 are found to be simulate very well the local atomic structure of Pd30Ni50P20 and Pd60Ni20P20 glasses, respectively. The best glass former in this series, Pd40Ni40P20, is best described by a weighted average of Pd30Ni50P20 and Pd60Ni20P20 structures. [Copyright &y& Elsevier]

Abstract: Low-Energy Ion Scattering (LEIS) spectroscopy is a technique with a unique sensitivity to the elemental composition of the surface top atomic layers of a solid. LEIS measurements of simple binary silicate glasses (with Na2O, Cs2O or BaO) have shown differences in composition between the as-cast glass surface and the vacuum-fracture surface. The as-cast surface is usually depleted of modifier ions compared to the nominal (batch) bulk glass composition, while the fracture surface is typically enriched with the monovalent modifier species, but not the divalent barium. While the melt surface depletion can probably be attributed to evaporation from the hot melt surface, the origin of the strong accumulation on the fracture surfaces is less clear. It is certainly possible that the fracture may have been preferentially guided by regions already alkali-enriched within the bulk of the glass. But considering the extreme surface sensitivity of this method, a surface-monolayer localized enrichment with alkali due to the stress gradient created by the fracture or the electric field created by dangling bonds on the vacuum-fractured surface is also possible. The Si/O ratio shows usually little deviation from the nominal glass batch value, falling within the estimated errors. [Copyright &y& Elsevier]

Laser heating can be used to produce single crystal architectures in glass with a lattice that rotates at a constant rate. Such metamaterials can offer properties that are disallowed by conventional crystal structures. To establish the mechanism of this lattice rotation, we used transmission electron microscopy (TEM) to directly observe and characterize dislocations in Sb 2 S 3 crystal lines fabricated in Sb-S-I glass as a model system. The lattice rotation calculated from the density and Burgers vectors of edge dislocations agrees with lattice rotation values experimentally determined by electron backscatter diffraction (EBSD) and selected area diffraction patterns (SADP). These results provide the first direct proof of the dislocation mechanism of lattice rotation in rotating lattice single (RLS) crystals, and very likely other forms of growth actuated bending, twisting and noncrystallographic branching as seen in spherulites. Image, graphical abstract [ABSTRACT FROM AUTHOR]

A carefully controlled femtosecond laser irradiation offers the possibility of fabricating high quality, 3D functional single-crystal patterns designed for integrated optical devices deep inside glass. Notwithstanding, a general theory relating particular irradiation conditions to crystal growth dynamics and resulting morphologies remains to be established. To overcome this challenge, crystal lines written in glass under varying conditions are investigated in this work by optical microscopy, scanning electron microscopy, and electron backscatter diffraction in the congruently crystallizing LaBGeO 5 model system. We show that despite a strongly preferential orientation of the optic axis along the direction of laser scanning, typical morphologies of fs laser-written crystals in this system are inhomogeneous due to low-angle grain boundaries and rotations or inversions of the preferential axis. Nevertheless, uniform single crystals can be produced under optimized irradiation conditions. The theoretical dynamics of crystal growth is developed within the unique environment of a moving laser-induced melt to explain these results, including the role of competitive growth in establishing the preferential lattice orientation; the effects of temperature gradient and focal scan rate in establishing crystal morphology and cross-section shape; and most notably, the specific design criteria that must be met for stable single-crystal growth. [ABSTRACT FROM AUTHOR]

We employ EXAFS spectroscopy to refine the local atomic arrangements of evaporation-deposited equiatomic GeSe film. Amorphous structure of the as-deposited GeSe film turns out to satisfy mainly the 4:2 structural model. The crystallized GeSe film, however, consists of the orthorhombic GeSe crystals with the 3:3 atomic arrangements and quasi-crystalline Ge clusters. Its temperature-dependent electrical resistance is explained in connection with this structural difference, which exemplifies significance of the chemical environments on the electrical switching phenomena observed from amorphous chalcogenide solids. [ABSTRACT FROM AUTHOR]

Abstract: Copper based oxide glasses are especially interesting for the possibility of ionic-electronic mixed conduction, which has potential applications in energy and switching devices. Accordingly, lithium metaphosphate glasses are investigated within the (100-x) Li2O - xCu2O - 50P2O5 series, where Li+ ions are gradually replaced by copper ions. Based on the changes in glass transition temperature and thermal stability via structural modification, the glasses are shown to be predominantly ionic conductors. In fact, they exhibit signs of classic mixed mobile ion effect (MMIE), a hallmark of ion conduction in glass, which would be due to Li+ and Cu+ ions in the present case. [Copyright &y& Elsevier]

Abstract: The use of high resolution X-ray photoelectron spectroscopy to study chalcogenide glass thin films is analyzed. It is shown that the method is an effective tool to explore different chemical environments in the films and control chemical composition of the surface. Examples of the method applications such as kinetics study of induced silver dissolution in the thin films and investigation of oxidation on the surface of the thin film are presented. Limitations of the method are shown on the example of photoinduced structural transformations in chalcogenide glass thin films. [Copyright &y& Elsevier]

Abstract: Changes of electronic and atomic structure during silver photodissolution in As2S3 thin film are studied using a combination of high-resolution X-ray photoelectron spectroscopy (XPS) and extended X-ray absorption fine structure (EXAFS) methods. It is shown that the photodiffusion process starts already under the influence of Al Kα and synchrotron X-ray probe radiations, forming a highly disordered metastable structure. Concurrent irradiation with UV/VIS light leads to the formation of a stable uniform ternary phase. The mechanisms of structural transformations and final chemical products are proposed. The influence of surface oxidation on the structure of Ag/As2S3 bilayer is also investigated. [Copyright &y& Elsevier]

Abstract: The as-quenched samples in the system (100− x) TeO2-(x) Ba5Li2Ti2Nb8O30 (2⩽ x ⩽8) were found to be embedded with 10–20μm sized crystallites of the polar phase Ba5Li2Ti2Nb8O30 (BLTN). Blue (400nm) second harmonic generation (SHG) was observed in transmission mode when 800nm laser light was allowed to pass through the individual crystallites. The blue SHG signal was temperature dependent and its intensity was maximum at ∼175°C which was tentatively attributed to the concomitant changes associated with the refractive indices of the BLTN crystallites. The SHG intensity attained a minimum value around the Curie temperature of BLTN crystals. [Copyright &y& Elsevier]

The surface of a high quality soda-lime silicate glass is found to be inhomogeneous, consisting of nanometer-high ridges that extend for tens of microns. Exposure to mild and aggressive environments results in an increase in the ridge heights as they dissolve much more slowly than the rest of the glass. The ridges also exhibit enrichment of sodium, magnesium, aluminum and oxygen. The parallel nature of the ridges suggests that they originate from compositional heterogeneity during the glass processing. [Copyright &y& Elsevier]

Distributed photovoltaic systems can cause adverse distribution system impacts, including voltage violations at customer locations and thermal overload of lines, transformers, and other equipment resulting from high current. The installed capacity at which violations first occur and above which would require system upgrades is called the hosting capacity. Current static methods for determining hosting capacity tend to either consider infrequent worst-case snapshots in time and/or capture coarse time and spatial resolution. Because the duration of violations cannot be captured with these traditional methods, the metric thresholds used in these studies conservatively use the strictest constraints given in operating standards, even though both worse voltage performance and higher overloads may be temporarily acceptable. However, assessing the full details requires accurately capturing time-dependence, voltage-regulating equipment operations, and performance of advanced controls-based mitigation techniques. In this paper, we propose a dynamic distributed photovoltaic hosting capacity methodology to address these issues by conducting power flow analysis for a full year. A key contribution is the formulation of time aware metrics to take these annual results and identify the hosting capacity. Through a case study, we show that this approach can more fully capture grid impacts of distributed photovoltaic than traditional methods and the dynamic hosting capacity was 60%–200% higher than the static hosting capacity in this case study. • Proposed dynamic study can more accurately capture a feeder's hosting capacity. • Proposed time aware metrics comply more closely with interconnection standards. • Traditional static methods cannot capture grid impacts like annual energy losses. • Static studies cannot assess the efficacy of smart inverter-based control schemes. • Case study and sensitivity analysis show the scalability of the proposed approach. [ABSTRACT FROM AUTHOR]

Abstract: We have investigated and compared vibrational modes of SiO2 and LaBGeO5 in the glass and crystalline phases based on terahertz (THz) spectroscopy. This is made possible by frequency-tuning a THz source developed by us recently. The THz absorption spectra are significantly different between the two phases of the same composition. In particular, we have identified the transition peak at 78.0μm for the SiO2 crystal (i.e. quartz). Moreover, we have observed an evidence for a boson peak in the spectrum for LaBGeO5 glass. [Copyright &y& Elsevier]

Abstract: GeSe2 and Ge28Sb12Se60 chalcogenide glass thin films have been deposited on single crystal silicon substrates by vacuum thermal evaporation. The surface morphology of these films has been investigated by field emission-scanning electron microscopy and atomic force microscopy, revealing heterogeneities in their microstructure consisting of granular regions ∼15–50nm in size, which were coarser in the case of the GeSe2 films. Typical RMS film surface roughness values were ∼0.9–1.3nm. [Copyright &y& Elsevier]