Phase Characteristics Research Articles

A case documenting distinct natural history of multizonal outer retinopathy and retinal pigment epitheliopathy (MORR) with longitudinal multi-modal documentation of progression

PurposeTo describe the clinical and imaging characteristics of the acute progressive phase of a recently proposed clinical entity, Multizonal Outer Retinopathy and Retinal Pigment Epitheliopathy (MORR), a variant of Acute Zonal Occult Outer Retinopathy (AZOOR) MethodsSingle observational case report. ResultsWe present the case of a 49-year-old myopic female with progressive outer retinopathy most consistent with a diagnosis of MORR. Through multimodal imaging and longitudinal follow-up, we delineate the clinical course and imaging findings of asymmetrical episodic progressive centrifugal extension of retinal pigment epithelial disturbance in both eyes, highlighting the features of an acute progressive episode not previously described. ConclusionsClinicians should be aware of the active clinical and multimodal imaging features of MORR and its distinction from other outer retinopathies due to its sight-threatening distinct clinical course, bilateral involvement with peripapillary lesions, and episodic progression into the macula. Additionally, we describe a “grass-fire” and “spot-fire” progression pattern during acute exacerbation, highlighting the need for vigilant monitoring and early intervention in MORR.

Synthesis and characterization of machine learning designed TADF molecules

In this study, we present a novel approach to the development of thermally activated delayed fluorescence (TADF) molecules with potentials for organic light-emitting diode (OLED) applications, leveraging machine learning (ML) algorithms to guide the materials design process. Recognizing the imperative for high-efficiency, low-cost emissive materials, we integrated ML driven models with experimental characterization to expedite the discovery of TADF compounds. Initially, a database of ML-designed TADF molecules was employed, with samples being approved to possess optimized photophysical properties. The proposed molecules were synthesized using palladium-catalyzed coupling reactions. Subsequent characterization of these molecules utilized a suite of analytical methods, including nuclear magnetic resonance (NMR) spectroscopy, photoluminescence (PL) spectroscopy, and transient PL decay etc., to confirm their structural integrity and evaluate their performance metrics. The photophysical analysis revealed notable emission efficiencies and significant delayed fluorescence characteristics in solution phases, underscoring the potential of ML-designed TADF molecules. Theoretical validations, through quantum chemical calculations, corroborated the experimental findings, demonstrating the predictive power of our ML models. This interdisciplinary approach not only accelerates the pace of TADF molecule development but also provides a scalable framework for future material innovation especially in the OLED research field.

The Impacts of Far‐Field Typhoon‐Generated Coastal Trapped Waves on the Hydrodynamics in the Northern South China Sea: A Case Study of Typhoon In‐Fa

AbstractCoastal Trapped Waves (CTWs) have the potential to transmit significant energy from atmospheric wind systems, causing dramatic coastal changes over vast areas, even far from the wind systems. This study investigated the impacts of CTWs generated by Typhoon In‐fa (2021) on the northern South China Sea (NSCS) hydrodynamics using tide gauge observations, reanalysis data, and numerical model outputs. The analysis results indicate that the CTWs induced by Typhoon In‐fa exhibit distinct characteristics in different phases of wave crest and trough. During the crest phase, coastal currents generated by CTWs flow opposite to the background circulation, while during the trough phase, they flow in the same direction. This process is accompanied by changes in cross‐shore currents, such that during the crest phase of CTWs, the cross‐shore currents are landward at the surface and seaward at the bottom, while during the trough phase of CTWs, the cross‐shore currents become reversed. These changes further lead to downwelling in temperature, salinity, and density during the crest phase of CTWs, and upwelling during the trough phase of CTWs. Results from a linear CTW model demonstrated that the above characteristics agreed with the traditional CTW theory. Sensitivity experiments with the Regional Ocean Model System (ROMS) explored key factors influencing NSCS hydrodynamics, including local winds and CTWs from Typhoon In‐fa. The local winds and CTWs have different effects: they compete during the crest phase and co‐work during the trough phase, with local winds dominating the sea surface and CTWs dominating the seabed.

Theoretical analysis of the phase characteristics in few-cycle laser coherent beam combining

To meet the increasing demand for high-energy (Joule-level) few-cycle pulses in strong-field physics research, coherent beam combining (CBC) presents an effective method to further enhance the power of few-cycle pulse sources. However, due to the broad spectrum and ultrashort pulse duration of few-cycle pulses, achieving efficient beam combining is particularly challenging. In this paper, we employ the angular spectrum (ASM) method to numerically simulate the propagation of few-cycle pulses in a focusing system. By constructing a three-dimensional (2D + 1D) model, we accurately quantify the effects of laser parameters such as carrier-envelope phase (CEP) difference, time delay (TD), dispersion between beams, and combining configurations on the combining efficiency and CEP shift. The study results provide design guidelines for high energy few-cycle laser systems based on coherent beam combining and reveal the possibility to significantly enhance the combining efficiency while maintaining high CEP stability, which will finally provide a reliable light source for advancing the frontier of strong-field physics.

Generalized representative structures for atomistic systems.

A new method is presented to generate atomic structures that reproduce the essential characteristics of arbitrary material systems, phases, or ensembles. Previous methods allow one to reproduce the essential characteristics (e.g., the chemical disorder) of a large random alloy within a small crystal structure. The ability to generate small representations of random alloys, along with the restriction to crystal systems, results from using the fixed-lattice cluster correlations to describe structural characteristics. A more general description of the structural characteristics of atomic systems is obtained using complete sets of atomic environment descriptors. These are used within for generating representative atomic structures without restriction to fixed lattices. A general data-driven approach is provided here utilizing the atomic cluster expansion (ACE) basis. TheN-body ACE descriptors are a complete set of atomic environment descriptors that span both chemical and spatial degrees of freedom and are used within for describing atomic structures. The generalized representative structure (GRS) method presented within generates small atomic structures that reproduce ACE descriptor distributions corresponding to arbitrary structural and chemical complexity. It is shown that systematically improvable representations of crystalline systems on fixed parent lattices, amorphous materials, liquids, and ensembles of atomic structures may be produced efficiently through optimization algorithms. With the GRS method, we highlight reduced representations of atomistic machine-learning training datasets that contain similar amounts of information and small 40-72 atom representations of liquid phases. The ability to use GRS methodology as a driver for informed novel structure generation is also demonstrated. The advantages over other data-driven methods and state-of-the-art methods restricted to high-symmetry systems are highlighted.

A Study on the Changes of Princess Images in Disney Animated Films

Abstract: There have been three feminist revolutions in history, and these movements have made great contributions to women's struggle for their own liberation and gender equality. From a feminist perspective, this article summarizes and analyzes the phased characteristics of the princess image in Disney animated films from 1937 to 2016, summarizing the development and evolution of the princess image in Disney films under the feminist wave in different periods, and finds that there is a certain connection between the two, which includes both the construction of social history and ideological order and the challenge to the social reality order. In general, the image of the princess seems to show obvious progressive characteristics, but there are different aspects and degrees of gender discrimination against the image of women in each stage. However, the different voices constructed by Disney in the film and the strategic adjustments made can still be regarded as a recognition of the power of feminism by the times and society.

Suitability of acoustic power amplifiers as power amplifiers in underwater communication systems

The paper presents selected acoustic power amplifiers from among those currently available. The results of a series of measurements characteris ing the amplifiers are presented. The measured amplitude and phase characteristics as a function of frequency for four selected amplifiers are analysed. The spectra of the output signal in the band from 4 kHz to 30 kHz are presented. The usefulness of the selected amplifiers in an underwater communication system is assessed.

The New Interpretation of the Photothermal Spectra of CdTe Samples After Different Surface Treatments

This article presents new research on the surface condition of bulk crystal samples after the following stages of surface treatment: grinding, polishing, and etching. Furthermore, it shows how the surface condition affects the photothermal signal’s spectral amplitude and phase characteristics (PZE). A new theoretical interpretation of the photothermal spectra of CdTe samples after different surface treatments is proposed. We demonstrate that the piezoelectric method is susceptible to the surface condition, and it allows for the estimation of the thickness of surface-damaged layers of samples, and for the analysis of their thermal parameters. The roughness of surfaces obtained from the AFM pictures is estimated and compared to the photothermal results.

Analysis on trends of mortality rate and disease burden of liver cancer in Tianjin, China from 1999 to 2021

Objective: To explore the trends and distribution of liver cancer between sexes, ages, and urban-rural areas in Tianjin, China from 1999 to 2021, and provide data for targeted prevention and control strategies of liver cancer in Tianjin. Methods: Liver cancer mortality data of Tianjin during 1999-2021 were from the Tianjin population based mortality surveillance system maintained by the Tianjin Centers for Disease Control and Prevention (CDC), and the population data of permanent Tianjin residents were from Tianjin Municipal Public Security Bureau. Liver cancer mortality, years of life lost (YLL), years lived with disability (YLD), and disability adjusted life years (DALY) were calculated using the cause of death surveillance data collected by Tianjin Centers for Disease Control and Prevention. The distributions of these data among residents of different sexes, ages, and regions were analyzed. Segi's world standard population was used for standardization. Joinpoint regression was used for trend analysis on the mortality rate of liver cancer and the disease burden. Results: The liver cancer mortality rate in Tianjin decreased by 46.75% from 1999 to 2021, with distinct phased characteristics. From 1999 to 2010, the age-sex-standardized mortality rate (SMR) decreased from 12.62/100 000 to 11.64/100 000 with an annual percent change (APC) of -1.32% (P=0.003). From 2010 to 2021, the SMR decreased from 11.64/100 000 to 6.72/100 000 (APC=-3.89%, P＜0.001). The age-sex-standardized DALY rates(SDR) decreased by 50.63% from 1999 to 2021, also with distinct phased characteristics. From 1999 to 2010, the SDR decreased from 388.67/100 000 to 349.38/100 000 (APC=-1.35%, P=0.002). From 2010 to 2021, the SDR decreased from 349.38/100 000 to 191.88/100 000 (APC=-4.43%, P＜0.001). The liver cancer mortality rate declined most rapidly in the age group under 45 years; the APC for those under 35 years was -5.07% (P＜0.001), and for those aged 35-44 years, the APC was 0.63% (P=0.707) and -8.21% (P＜0.001) before and after 2007, respectively. Both SMR and SDR were significantly higher in males than in females (P＜0.01). Both SMR and SDR were significantly higher in urban areas than in rural areas from 1999 to 2007 (P＜0.05), but they became similar after 2008. Liver cancer DALY are predominantly YLL, accounting for 99%. The median age of liver cancer deaths in Tianjin during 1999-2021 was 64-68 years old, with males lower than females (P＜0.05), and rural areas lower than urban areas (P＜0.05), generally showing an increasing trend (1999-2014: APC=0.11%, P=0.047; 2014-2021: APC=0.51%, P=0.005). Conclusions: Liver cancer mortality rate and disease burden decreased from 1999 to 2021 in Tianjin, with an especially accelerated decline after 2010. Further efforts to reduce liver cancer mortality in Tianjin are needed, and special attention should be focused on the elderly, male, and rural residents.

Using machine learning towards enhancement of electrochemical activity in OER/ORR half-reactions of MXene cathode materials for Li-air batteries

Metal-air batteries are the target of the ever-growing interest as considering as the new “lead” technology among the most promising electrochemical energy storage solutions. The projected energy density of lithium-air batteries considered in this study exceeds current commercial lithium-ion batteries by more than three times. In this study, we consider the characteristics of MXenes, 2D layered phases with such attractive characteristics as a high specific surface area with the numerous active reaction centers, mechanical strength, the diverse functional characteristics and the perspectives of scalability of their production, which are of importance for the practical realization of Li-air batteries of different architecture. The formation of the phases of complex content and structure inherent to pseudomorphism at the interface, as it is actual for the objects of our study, allows one to conclude that it is necessary to consider the processes that occur at the interfaces of lithium-air battery cathodes in direct relation to the cathode material used. Machine learning methods were involved in model development for (i) MXenes predicting the electrochemical phase diagrams, Pourbaix diagrams, which circumscribe the stability window of MXenes of certain composition formed with synthesis-defined terminations as a function of pH and USHE for single and double MXenes and (ii) the elastic characteristics of MAX phases, precursors of MXenes, to assess the commensurability of the interface of MXene cathode materials and Li2O2 phase as well as the prospects of using target MXene compositions combined with the solid electrolyte materials of different families for employing in all-solid-state Li-air batteries. The obtained models demonstrate high predictive performance that argue on the possibility to use them for rational screening of new phases with desired functional characteristics.

APPLICATION OF AMPLITUDE-FREQUENCY-MODULATED SIGNALS FOR HYDROCARBON SEARCH

The phase characteristics of the surface impedance of the medium above hydrocarbon deposits were studied in the mode of their interaction with amplitude-frequency-modulated signals. The characteristics of the geological profile above oil and gas deposits were investigated depending on the carrier frequency, modulating frequency and modulation index. The rationale for using sounding with amplitude-frequency-modulated signals for practical implementation in order to increase the information content and accuracy of determining hydrocarbon boundaries was provided. A method for geoelectric exploration was developed to determine hydrocarbon boundaries using amplitude-frequency-modulated signals based on measuring the phase characteristics of the surface impedance of the medium above the deposits. The results obtained can be used for exploration geophysics in order to detect oil and gas deposits.

Dependency of amplitude and phase characteristics of vasomotor oscillations on visual stimulation conditions and experiment duration

The intrinsic-signal optical imaging is widely used in experimental, theoretical and applied research of the mammal’s brain neocortex functional anatomy. However, a neural activity signal is hidden by the background activity, the amplitude of which is an order of magnitude larger than the mapping signal amplitude. Most of such background activity represents spontaneous oscillations in 0.01–0.15 Hz frequency range related to vasomotor oscillations. In this paper, we point out that such oscillations change their power and phase during the response time course. The most dramatic influence is intrinsic for 0.05–0.15 Hz oscillations. The power of vasomotor oscillations declines more quickly than the stability features of their phase characteristics. Departing from these data, we suggested approaches for minimization of role of vasomotor oscillations in functional maps resulting from intrinsic-signal optical imaging.

An empirical model of the kinetics of hydrogen-induced cracking in pipeline steel, using statistical distribution models and considering microstructural characteristics and hydrogen diffusion parameters

This study proposes an empirical model to predict the kinetics of hydrogen-induced cracking (HIC) growth rate in pipeline steels based on experimentally measured hydrogen diffusion parameters and spatial distribution of microstructural features previously identified to have a role on HIC kinetics. In the experimental work, the HIC was induced by electrochemical cathodic charging and the crack growth was monitored by ultrasonic inspection. Optical and scanning electron microscopy were used to determine the spatial distribution parameters of non-metallic inclusions, and the ferrite grain and second phase characteristics. The hydrogen microprint technique used to visualize hydrogen diffusion path in the microstructure and the hydrogen diffusion parameters were determined by hydrogen permeation tests. Results show that NMI shape affects HIC nucleation sites, using student's t-distribution, while ferrite grain characteristics affect HIC growth rates, with X70–2 and X56 steel plates recorded highest HIC growth rate. The Log-Normal distribution model, supported by statistical analysis, effectively predicts HIC growth rates compared with Weibull and Gamma distribution models.

Research on the Strengthening Mechanism of MWCNTs-Cuf Composite Interlayer for Si3N4/TC4 Brazed Joints

With the rapid development of aerospace technology, the high-quality brazing connection between Si3N4 ceramic and TC4 titanium alloy has become a key factor in advancing the development of aircraft antenna covers. To improve the mechanical strength of the joints, this study used the electrophoretic deposition method to prepare a multi-walled carbon nanotubes-foam copper (MWCNTs-Cuf) composite interlayer and selected the optimal deposition parameters. The most suitable brazing parameters under this interlayer were also determined. The joints’ formation mechanism and fracture mode were revealed to elucidate the synergistic strengthening mechanism of the composite interlayer. The results showed that MWCNTs, based on their phase characteristics, produced high-density dislocations and fine crystal strengthening effects during the brazing cooling process. This effectively resisted the corrosion of the brazing material on the foam copper (Cuf), protected the integrity of the foam copper framework, and exerted the excellent plastic deformation ability of foam copper (Cuf). It reduced the residual stress in the joints, resulting in the highest shear strength of the MWCNTs- Cuf composite interlayer, reaching 96.23 MPa. Compared with only adding Ag-Cu-Ti active brazing filler metal and adding ordinary foam copper interlayer, the shear strength increased by 78.2% and 44.7%, respectively.

On the interplay between fluid flow characteristics and small particle deposition in turbulent wall bounded flows

This study investigates the transport and deposition of small particles (500 nm≤dp≤10 μm) in a fully developed turbulent channel flow, focusing on two fluid friction Reynolds numbers: Reτ=180 and Reτ=1000. Using the point particle–direct numerical simulation method under the assumption of one-way coupling, we study how fluid flow (carrier phase) characteristics influence particle deposition. Our findings suggest that changes in flow conditions can significantly alter the deposition behavior of particles with the same size and properties. Furthermore, we show for the first time that gravity has minimal impact on deposition dynamics only at high Reynolds numbers. This research enhances our understanding of small particle deposition and transport in turbulent flows at high Reynolds numbers, which is crucial for various industrial applications.

Exploration of Geographical Environmental Factors Influencing Regional Population Mortality Patterns inChina.

The regional population mortality patterns in China exhibit substantial geographical distribution characteristics. This paper aims to explore the impact and mechanisms of geographical environmental factors on regional population mortality patterns. This study first utilized the data from China's Seventh Population Census to obtain mortality patterns for the 31 provincial-level administrative regions. Subsequently, a functional regression method was employed to explore the geographical environmental driving factors of regional mortality patterns. The study provides a detailed explanation of the mechanisms and marginal contributions of key geographical environmental factors at different age groups. (1) The impact of geographical environmental factors on mortality patterns shows distinct phased characteristics. Mortality patterns before the age of 40 years are hardly influenced by geographical environmental factors, with a noticeable impact beginning at ages 40-69 years and reaching the maximum influence after the age of 70 years. (2) In mortality patterns at ages 40-69 years, average altitude have the most substantial impact, followed by extreme low-temperature days and PM2.5 concentration. In mortality patterns at ages 70-94 years, high-temperature days have the greatest influence, followed by the impact of SO2 concentration. (3) In comparisons based on gender, socioeconomic factors, and geographical environmental factors, gender and urban-rural differences have the most significant impact on regional population mortality patterns, followed by the influence of other socioeconomic factors, with geographical environmental factors having a relatively smaller impact.

3D printing of cordierite glass-ceramics

Compared to traditional ceramic materials, glass-ceramics can also exhibit superior properties and are now widely used in cutting-edge national defense industries technology, aerospace, electronics, construction, and other fields. In this study, it is for the first time reported that novel photopolymerization 3D printable slurries using cordierite glass ceramic powder were prepared. The effects of slurry properties and printing process parameters on the warpage of the printed samples were studied. Cordierite glass-ceramic parts fabricated using photopolymerization 3D printing and heat treatment processes were studied to evaluate the effects of sintering parameters on the properties of the samples. The obtained additively manufactured cordierite glass-ceramics exhibit excellent microstructural and mechanical properties, with a maximum bending strength of 181 MPa, an increase of 95.66 % compared to that of the previously reported 3D printed cordierite ceramics. The underlying mechanisms of the glass and ceramic phase characteristics influence the density and the mechanical properties during and after the courses of sintering were also investigated and unveiled in detail. This study provides a viable method for manufacturing complex-shaped cordierite glass-ceramic components using 3D printing.

High-efficiency wide-angle anomalous refraction with acoustic metagrating

Abstract The emergent metagrating, with its unique and flexible beam shaping capabilities, offers new paths to efficient modulation of acoustic waves. In this work, an acoustic metagrating is demonstrated for high-efficiency and wide-angle anomalous refraction. It is shown that the normal reflection and transmission can be totally suppressed by properly modulating the amplitude and phase characteristics of the metagrating supercells for high-efficiency anomalous refraction. The anomalous refraction behavior is achieved in the wide range of incident angles from 28° to 78°, and the efficiency of -1st order diffraction is higher than 90% by finely designing the metagrating structure. The anomalous refraction behaviors are verified experimentally at incidence angle of 28°, 45° and 78°, respectively. The demonstrated metagrating is anticipated to possess efficient wide-angle composite wavefront engineering applications in such fields as communications.

Study on the damage characteristics of high-temperature superconducting cable insulation under air gap discharge

This study explores the impact of small air gaps in high-temperature superconducting cables on the insulating material polypropylene-laminated paper (PPLP), and the aging rules and mechanisms of the insulating material during practical uses. An air gap discharge test platform was built to simulate air gap fault defects of superconducting cables in the real operating environment. Hierarchical clustering method was used to divide the gap discharge process of defect model into four stages. Insulation damage assessment was conducted on the intermediate layer PP of the superconducting insulation material PPLP at different discharge stages, revealing surface changes and periodic alterations in dielectric properties. The morphological features, roughness, infrared spectra, dielectric loss, surface resistivity, and other phase characteristics of the superconducting insulation layer material were analyzed at different stages of air gap defects. Molecular group cracking in PP was attributed to the bond breakage on the main chain. These findings provide insights into high-temperature superconducting cable insulation under air gap discharge and provide a guideline for practical applications in semi-conductive industries.

Investigation of Structural Phase, Mechanical, and Tribological Characteristics of Layer Gradient Heat-Protective Coatings Obtained by the Detonation Spraying Method.

This paper presents the results of a study of layer gradient thermal protection coatings based on NiCrAlY and YSZ obtained by detonation spraying. Modern gas turbines and high-temperature units operate under extreme temperatures and aggressive environments, which requires effective protection of components from wear, corrosion, and thermal shocks. In this study, the use of layer gradient coatings consisting of alternating layers of NiCrAlY and YSZ was investigated with the aim of solving the problem of thermal stress accumulation due to a smooth change in the composition of the layers. Microstructural and phase analysis showed that alternating layers of NiCrAlY and YSZ formed a dense layer gradient structure with clear interphase boundaries and low porosity. Detonation spraying led to a complete transformation of the monoclinic ZrO2 phase into a tetragonal one, which significantly increased the mechanical strength of the coating and its resistance to thermal shocks. Sample 1D1 demonstrated excellent tribological and corrosion properties in a 3.5% NaCl solution, which can be explained by its higher density and reduced number of pores. Mechanical tests revealed stable values of hardness and wear resistance of the coating, especially for the 1D1 coating. Studies have shown that coatings are resistant to thermal shocks, but thicker layers show a tendency to peel off after thermal cycling. The obtained results indicate high prospects for the use of layer gradient coatings based on NiCrAlY and YSZ for the protection of gas turbine components and other high-temperature installations operating under extreme loads and aggressive environments.