Polarity Index Research Articles

Long-Term High-Fat Diet Impairs AQP4-Mediated Glymphatic Clearance of Amyloid Beta.

As a risk factor for Alzheimer's disease (AD), studies have demonstrated that long-term high-fat diet (HFD) could accelerate the deposition of amyloid beta (Aβ) in the brain. The glymphatic system plays a critical role in Aβ clearance from the brain. However, studies investigating the effects of long-term HFD on glymphatic function have reported paradoxical outcomes, and whether glymphatic dysfunction is involved in the disturbance of Aβ clearance in long-term HFD-fed mice has not been determined. In the present study, we injected fluorescently labeled Aβ into the hippocampus and found that Aβ clearance was decreased in HFD-fed mice. We found that long-term HFD-fed mice had decreased glymphatic function by injecting fluorescent tracers into the cisterna magna and corpus striatum. In long-term HFD-fed mice, aquaporin-4 (AQP4) polarization in the cortex was disrupted, and glymphatic clearance activity was positively correlated with the AQP4 polarization index. In HFD-fed mice, the disturbance of Aβ clearance from the hippocampus was exacerbated by TGN-020, a specific inhibitor of AQP4, whereas TGN-073, an enhancer of AQP4, ameliorated it. These findings suggest that long-term HFD disrupts Aβ clearance by inhibiting AQP4-mediated glymphatic function. The underlying mechanism may involve the disruption of AQP4 polarization.

Comparative evaluation on chemical composition and in vitro anti-Fusarium activity of solvent extracts of Zingiberaceae rhizomes from Indonesia

Fusarium oxysporum f.sp. cubense (Foc) is a fungus that not only causes disease while bananas are being grown, but it also causes begetting after bananas are harvested, which limits the production of bananas. Zingiberaceae plants contain a high number of extractable secondary metabolites that are regarded to have effective antifungal activities. However, in order for the compounds to be suitable for use, they must be tested by modifying the polarity in the extracting solvent. In this study, four Zingiberaceae species were examined, namely Zingiber officinale, Curcuma longa, C. zanthorrhiza, and Alpinia galanga. The extraction of rhizomes of each plant was accomplished by using solvents with distinct polarity index (PI) viz. water (PI 9.0); a mixture of 50% water and 50% ethanol (PI 7.1); ethanol (PI 5.2); and n-hexane (PI 0.0). The anti-Fusarium evaluation of these 16 extracts was carried out in vitro by implementing the pour plate method in potato dextrose agar (PDA). Our results showed that the C. zanthorrhiza n-hexane extract possessed the greatest antifungal activity among other extracts. The fungal inhibition ability of the extracts was negatively correlated with the increase in solvent polarity index. In order to comprehend our understanding of the antifungal activity, the chemical compositions of each extract were identified through non-targeted Gas Chromatography–Mass Spectrometry (GC-MS), showing the main components of the n-hexane extracts were terpenes and terpenoids. Particularly, C. zanthorrhiza n-hexane extract contained, with the percentage of abundance in parentheses, germacrene B (22.99%), β-farnesene (14.72%), curzerene (10.87%), 2-bornanone (9.60%), α-curcumene (9.32%), zingiberene (8.30%), β-curcumene (6.36%), β-elemene (5.31%), caryophyllene (3.36%), cedrene (2.73%), α-bergamotene (1.36%), and humulene (0.20%). As conclusion, this crude extract or its pure chemical constituents have potential application as biofumigant to control Foc in postharvest banana.

How Can Digital Maps of Religions Inform Us about Fractionalization and Polarization in Post-Communist Romania?

This study explores religious diversity in Romania and how the trends of indices of religious fractionalization and polarization manifest at the county level in a post-communist period. The county level was selected as the relevant level for analysis due to its more clearly visible spatial dynamics with regard to religions. Recent studies have revealed that the erosion of diversity is an important aspect for any country and needs to be considered as an important aspect of democracy. This paper highlights how digital mapping of religious polarization and fractionalization in Romania has been generally maintained, although the regions of Transylvania, Banat, Dobrogea and Western Moldova remain areas in which there are different religions. Other than the general aspect of religious diversity depending on ethnic trends, there has been a rise of Pentecostals and Baptists at the county level. This aspect has further implications for our study, which calls for creating new institutions for dialogue between majority Orthodox communities and Protestants, not only so that potential conflicts do not appear between Orthodox and emerging religious communities but also to ensure objective, cultural, religious coherence. Our maps revealed the distribution patterns and the temporal evolution of religious denominations for the 1992–2011 period. The major line of originality in our research rests in the findings that after conducting a bivariate spatial autocorrelation analysis of religious fractionalization and polarization, we were able to identify two distinct clusters with spatial overlap over historical provinces.

Bioinformatics Characteristics and Genomic Patterns of the Envelope Glycoproteins of the Crimean-congo Hemorrhagic Fever Viruses

Background: Rodents and many wild and domestic animals, including cattle, donkeys, goats, hares, ostriches, and sheep, spread the Crimean-Congo Hemorrhagic Fever Virus (CCHFV), acting as hosts for infected ticks primarily of the Hyalomma genus, which serve as vectors and reservoirs of the virus. CCHF is a severe, potentially lethal, and widespread disease, making it a serious public health issue. Environmental changes impacting rodent populations affect their global distribution and, therefore, play a role in the spread of CCHFV. Objective: This study aims togain a deeper understanding of the envelope glycoproteins expressed by the CCHFV. Methods: Multiple computational algorithms determined the Intrinsic Disorder Predisposition (PIDP), Polarity Index, and genomic profiles of each sequence of the glycoproteins. Results: When examining the Polarity Index Method Profile, 3.0v profile, and the PIDP profile, the envelope glycoproteins of the CCHFV showed different patterns. With these patterns, it was possible to identify structural and morphological similarities. Conclusion: With the PIM 3.0v profile, our computer programs were able to identify isolated CCHFV envelope glycoproteins. We believe that this research provides a deeper understanding of this virus. conclusion: Using the PIM 3.0v profile, our computer programs were able to identify isolates of the CCHFV envelope glycoproteins. We believe that this research contributes to a deeper understanding of this emerging virus.

D-π-A Carbzazole Based Reactive Cyano-Substituted C = C bond Probe for Selective and Sensitive Detection of Hydrazine in Aqueous Media.

This work established a newly designed and synthesized carbazole N-phenyl π-conjugated vinyl malononitrile (CPM) fluorescent sensor, which showed typical and remarkable redshift emission properties with different polarity index solvents. Investigative probe CPM is colorimetric and fluorimetric ultrafast and ultrasensitive detection of hazardous hydrazine in an aqueous medium. Furthermore, CPM showed colorimetric and fluorometric responses to interference tests with other amines and high selectivity for detecting hydrazine without interference with other amines in colorimetric and fluorimetric methods. This probe CPM for hydrazine was as low as the lower detection limit value of 2.21 × 10- 8 M. The probe CPM expects significant attention due to its simplicity and cost-effectiveness in detecting hazardous hydrazine. UV-vis, PL, NMR, and MS spectra confirmed the mechanism of probe CPM detection of hazardous hydrazine. However, making a piece test kit attractive for practical hydrazine vapor leak-detection applications is easy. This study can be applied to many pipeline gas transmission industries and transportation facility sectors.

Improving the identification of bone-specific physical activity using wrist-worn accelerometry: A cross-sectional study in 11-12-year-old Australian children.

Physical activity (PA) during childhood and adolescence is important for the accrual of maximal peak bone mass. The precise dose that benefits bone remains unclear as methods commonly used to analyze PA data are unsuitable for measuring bone-relevant PA. Using improved accelerometry methods, this study identified the amount and intensity of PA most strongly associated with bone outcomes in 11-12-year-olds. Participants (n=770; 382 boys) underwent tibial peripheral quantitative computed tomography to assess trabecular and cortical density, endosteal and periosteal circumference and polar stress-strain index. Seven-day wrist-worn raw acceleration data averaged over 1-s epochs was used to estimate time accumulated above incremental PA intensities (50 milli-gravitational unit (mg) increments from 200 to 3000mg). Associations between time spent above each 50mg increment and bone outcomes were assessed using multiple linear regression, adjusted for age, sex, height, weight, maturity, socioeconomic position, muscle cross-sectional area and PA below the intensity of interest. There was a gradual increase in mean R2 change across all bone-related outcomes as the intensity increased in 50mg increments from >200 to >700mg. All outcomes became significant at >700mg (R2 change=0.6%-1.3% and p=0.001-0.02). Any further increases in intensity led to a reduction in mean R2 change and associations became non-significant for all outcomes >1500mg. Using more appropriate accelerometry methods (1-s epochs; no a priori application of traditional cut-points) enabled us to identify that ∼10min/day of PA >700mg (equivalent to running ∼10km/h) was positively associated with pQCT-derived measures of bone density, geometry and strength in 11-12-year-olds.

Large-size 19-channel monolithic silicalite-1 membranes for butane separation: Separation performance and quantification of concentration polarization

Developing an energy-saving membrane technology is important for the separation of hydrocarbon isomers. For the first time, separation performance of large-size 19-channel monolithic silicalite-1 membranes and the correlation of the performance with concentration polarization index were reported for separating industrial n-/i-butane (n-/i-C4) mixtures. The effective membrane area of each element was up to 0.1 square meters. Four membranes showed average n-C4 permeance and n-/i-C4 separation factor of (3.8 ± 0.1) × 10-8 mol/(m2 s Pa) and 27.5 ± 0.58 at 333 K, respectively. The impact of operating parameters and concentration polarization on separation performance of the typical monolithic membrane were investigated. Two solutions were proposed to reduce the influence of concentration polarization. The correlation of separation performance and concentration polarization can be used for performance prediction. The large-size silicalite-1 membranes exhibited long-term stability in the separation of butane isomers.

Synergetic Use of Sentinel-1 and Sentinel-2 Data for Wheat-Crop Height Monitoring Using Machine Learning

Monitoring crop height during different growth stages provides farmers with valuable information important for managing and improving expected yields. The use of synthetic aperture radar Sentinel-1 (S-1) and Optical Sentinel-2 (S-2) satellites provides useful datasets that can assist in monitoring crop development. However, studies exploring synergetic use of SAR S-1 and optical S-2 satellite data for monitoring crop biophysical parameters are limited. We utilized a time-series of monthly S-1 satellite data independently and then used S-1 and S-2 satellite data synergistically to model wheat-crop height in this study. The polarization backscatter bands, S-1 polarization indices, and S-2 spectral indices were computed from the datasets. Optimized Random Forest Regression (RFR), Support Vector Machine Regression (SVMR), Decision Tree Regression (DTR), and Neural Network Regression (NNR) machine-learning algorithms were applied. The findings show that RFR (R2 = 0.56, RMSE = 21.01 cm) and SVM (R2 = 0.58, RMSE = 20.41 cm) produce a low modeling accuracy for crop height estimation with S-1 SAR data. The S-1 and S-2 satellite data fusion experiment had an improvement in accuracy with the RFR (R2 = 0.93 and RMSE = 8.53 cm) model outperforming the SVM (R2 = 0.91 and RMSE = 9.20 cm) and other models. Normalized polarization (Pol) and the radar vegetation index (RVI_S1) were important predictor variables for crop height retrieval compared to other variables with S-1 and S-2 data fusion as input features. The SAR ratio index (SAR RI 2) had a strong positive and significant correlation (r = 0.94; p < 0.05) with crop height amongst the predictor variables. The spatial distribution maps generated in this study show the viability of data fusion to produce accurate crop height variability maps with machine-learning algorithms. These results demonstrate that both RFR and SVM can be used to quantify crop height during the growing stages. Furthermore, findings show that data fusion improves model performance significantly. The framework from this study can be used as a tool to retrieve other wheat biophysical variables and support decision making for different crops.

Estimation of Ultrasonic Velocity, Density, Internal Pressure, and Thermophysical Parameters of Ionic Liquid Mixtures: Application of Flory's Statistical Theory.

Flory's statistical theory (FST) has been employed to estimate the ultrasonic velocity, density, internal pressure, and several important thermophysical parameters such as the energy of vaporization, the heat of vaporization, cohesive energy density, polarity index, and solubility for eight binary mixtures of ionic liquids and water within the temperature range of 288.15 to 308.15 K. The ionic liquids chosen for this investigation are [BMim][dca], [BMim][TfO], [BMpy][TfO], [BMpyr][dca], [BMpyr][TfO], [EEPy][ESO4], [HMim][dca], and [MPy][MSO4]. The predicted values of ultrasonic velocity and density show good agreement with the data reported in the literature. It endorses the applicability of FST to these binary mixtures. A comparative analysis of the internal pressure values (Pi) determined by using FST and the standard thermodynamic approach is also presented. The results obtained for Pi using both approaches show good agreement. Besides, for the mixtures under study, the correlation between ultrasonic velocity, density, and surface tension has also been examined. The variation of thermophysical parameters with concentration and temperature changes has been utilized to explore the nature and strength of the solute-solvent interactions prevalent in these mixtures. It is pointed out that A-A-type interactions dominate over A-B-type interactions in water-rich regions of the mixtures.

Hybridizing genetic random forest and self-attention based CNN-LSTM algorithms for landslide susceptibility mapping in Darjiling and Kurseong, India

Landslides are a prevalent natural hazard in West Bengal, India, particularly in Darjeeling and Kurseong, resulting in substantial socio-economic and physical consequences. This study aims to develop a hybrid model, integrating a Genetic-based Random Forest (GA-RF) and a novel Self-Attention based Convolutional Neural Network and Long Short-term Memory (SA-CNN-LSTM), for accurate landslide susceptibility mapping (LSM) and generate landslide vulnerability-building map in these regions. To achieve this, we compiled a database with 1830 historical data points, incorporating a landslide inventory as the dependent variable and 32 geo-environmental parameters from Remote Sensing (RS) and Geographic Information Systems (GIS) layers as independent variables. These parameters include features like topography, climate, hydrology, soil properties, terrain distribution, radar features, and anthropogenic influences. Our hybrid model exhibited superior performance with an AUC of 0.92 and RMSE of 0.28, outperforming standalone SA-CNN-LSTM, GA-RF, RF, MLP, and TreeBagger models. Notably, slope, Global Human Modification (gHM), Combined Polarization Index (CPI), distances to streams and roads, and soil erosion emerged as key layers for LSM in the region. Our findings identified around 30% of the study area as having high to very high landslide susceptibility, 20% as moderate, and 50% as low to very low. The vulnerability-building map for 244,552 building footprints indicated varying landslide risk levels, with a significant proportion (27.74%) at high to very high risk. Our model highlighted high-risk zones along roads in the northeastern and southern areas. These insights can enhance landslide risk management in Darjeeling and Kurseong, guiding sustainable strategies for future damage qualification.

Effects of Atmospheric Pressure Plasma Jet on 3D-Printed Acrylonitrile Butadiene Styrene (ABS).

Polymers are essential in several sectors, yet some applications necessitate surface modification. One practical and eco-friendly option is non-thermal plasma exposure. The present research endeavors to examine the impacts of dielectric barrier discharge atmospheric pressure plasma on the chemical composition and wettability properties of acrylonitrile butadiene styrene surfaces subject to the action of additive manufacturing. The plasma source was produced by igniting either helium or argon and then adjusted to maximize the operational conditions for exposing polymers. The drop in contact angle and the improvement in wettability after plasma exposure can be due to the increased oxygen-containing groups onto the surface, together with a reduction in carbon content. The research findings indicated that plasma treatment significantly improved the wettability of the polymer surface, with an increase of up to 60% for both working gases, while the polar index increased from 0.01 up to 0.99 after plasma treatment. XPS measurements showed an increase of up to 10% in oxygen groups at the surface of He-plasma-treated samples and up to 13% after Ar-plasma treatment. Significant modifications were observed in the structure that led to a reduction of its roughness by 50% and also caused a leveling effect after plasma treatment. A slight decrease in the glass and melting temperature after plasma treatment was pointed out by differential scanning calorimetry and broadband dielectric spectroscopy. Up to a 15% crystallinity index was determined after plasma treatment, and the 3D printing process was measured through X-ray diffraction. The empirical findings encourage the implementation of atmospheric pressure plasma-based techniques for the environmentally sustainable manipulation of polymers for applications necessitating higher levels of adhesion and specific prerequisites.

Toward an alternative measure of board diversity: an exploratory study on board polarization in German stock exchange-listed companies

PurposeThe effects of board composition on performance have long been discussed in management research using fractionalization measures. In this study, we propose an alternative measurement approach based on board polarization.Design/methodology/approachUsing an exploratory analysis and applying the polarization measure to German Deutscher Aktienindex (DAX)-, Midcap-DAX (MDAX)- and Small Cap-Index (SDAX)-listed companies, this paper applies the polarization index to examine the relationship between board diversity and performance.FindingsThe results show that the polarization concept is well suited to measure principal-agent problems between the members of the management and supervisory boards. We reveal that board polarization is negatively associated with firm performance, as measured by return on investment (ROI).Originality/valueThis exploratory study shows that the measurement of board polarization can be linked to performance differences between companies, which offers promising starting points for further research.

Polarity-driven distribution of the non-aqueous tear components during microdesiccation on flat glass surfaces

Spontaneous desiccation of microvolumes of tear from a healthy subject on flat glass surfaces produces highly reproducible supramolecular structures called tear microdesiccate. In the process, non-aqueous tear components organize four main radially distributed morphological domains (zones I, II, III, and transition band or TB) through non-well understood mechanisms. Tear lipids have been located in the outermost domains (ZI, TB), thus suggesting that tear components in microdesiccate are partitioned according to electric polarities. Using a combination of dark-field and contrast phase transmitted-light microscopy, we have now studied the impact on preformed tear microdesiccate of a series of six small-sized monohydric alcohols (methanol, ethanol, n-propanol, n-butanol, n-pentanol, 2-propanol; C1 through I-C3) ranked according to polarity index (P.I. 0.762–0.546). Water (P.I. 1.000) served as control. The study aimed to assess the influence of the electric polarity of the alcohols on the organization of the microdesiccate domains.The study revealed self-assembly as a mechanism underlying formation of the entire microdesiccate as shown by the fully disruptive effect of water on preformed tear microdesiccate and their reorganization following a new desiccation cycle. Devastating effects of the most polar alcohol in the assay (methanol) were observed particularly on the centermost domain (zone III), and secondarily on zone II. Contrarily, the less polar alcohols (C2 to C5) showed both fixative effects on crystalloids of ZII and ZIII and differential unveiling of filamentous structures in ZI and TB probably due to selective extraction of lipid-like components from these latter two domains. Those effects on microdesiccate from different subjects were highly reproducible, thus supporting the view that these tear specimens bear a common design.Microdesiccates from normal tears produced on flat glass surfaces are self-assembled structures based on a design including a radial gradient of charge polarities spanning from the lipid-rich outermost hydrophobic domain (ZI) to the centermost hydrophilic fern-like crystalloid-rich domain (ZIII).

Polarization Characterization of Porous Particles Based on DDA Simulation and Multi-Angle Polarization Measurements.

Porous suspended particles are hazardous to human health due to their strong absorption capacity for toxic substances. A fast, accurate, in situ and high-throughput method to characterize the microporous structure of porous particles has extensive application value. The polarization changes during the light scattering of aerosol particles are highly sensitive to their microstructural properties, such as pore size and porosity. In this study, we propose an overlapping sphere model based on the discrete dipole approximation (DDA) to calculate the polarization scattering characteristics of porous particles. By combining scattering calculations with multi-dimensional polarization indexes measured by a multi-angle polarized scattering vector detection system, we achieve the identification and classification of pore-type components in suspended particles. The maximum deviation based on multiple indexes is less than 0.16% for the proportion analysis of mixed particles. Simultaneously, we develop a quantitative inversion algorithm on pore size and porosity. The inversion results of the three porous polymer particles support the validity and feasibility of our method, where the inversion error of partial particles is less than 4% for pore size and less than 6% for porosity. The study demonstrates the potential of polarization measurements and index systems applied in characterizing the micropore structure of suspended particles.

Exploring ionic liquids for the extraction separation of aromatic hydrocarbons from diesel via multiple interaction analyses coupled with experimental evaluation

The separation of aromatic hydrocarbons from petroleum fractions is of great significance for both the quality upgrading of products and value-added utilization of aromatic compounds. However, the separation of polycyclic aromatic hydrocarbons (PAHs) and their derivatives from diesel remains challenging because of their lower solubility and selectivity as compared to the monocyclic aromatic compounds. In this work, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][TF2N]) was screened from 320 ionic liquid (IL) candidates through solvent capacity predication using COSMO-RS method. Liquid-liquid equilibrium experiments were carried out using a series of tetralin/n-decane mixtures with different tetralin concentrations to evaluate the extraction performance of several solvents. The results indicate that [EMIM][TF2N] has high selectivity up to 95.73 for tetralin over n-decane, which is 4.5 and 3.9 times higher than that of dimethyl sulfoxide and sulfolane. During five regeneration cycles, the [EMIM][TF2N] exhibits consistent extraction performance and nearly complete recovery. Molecular polarity index (MPI) analysis indicates that tetralin has larger dissolving affinity to solvents as compared to n-decane. Combined analyses of interaction energy, energy decomposition, and visualization of weak interaction reveal that the crucial role of weak hydrogen bond in dominating the complex solvent–solute interactions. Compared to n-decane, tetralin shows a stronger interaction with the solvents due to the existence of C-H···π and hydrogen bond interactions. The great difference in interaction energy between {[EMIM]+ + tetralin} and {[EMIM]+ + n-decane}, therefore, endows [EMIM][TF2N] with high selectivity for tetralin. Given the dominant role of cation, a IL, [CN1 = C2SCCS2(CC = C)C1][TF2N] having both high selectivity and high solvent capacity was subsequently explored using the cation generation method based on the SeqVAE model. Furthermore, present study proposes a strategy for the design of ILs for separation and other specific application circumstances.

Exosomes from SHED-MSC regulate polarization and stress oxidative indexes in THP-1 derived M1 macrophages

ObjectiveThe inhibition of M1 macrophages may be interesting for targeted therapy with mesenchymal stem cell-derived Exosomes (MSC-EXOs). This study aimed to investigate the stem cells of human exfoliated deciduous teeth-derived EXOs (SHED-MSC-EXOs) effect on regulating the pro- and anti-oxidant indexes and inhibiting M1 macrophage polarization. Besides, an in-silico analysis of SHED-MSC-EXO miRNAs as the highest frequency of small RNAs in the exosomes was performed to discover the possible mechanism. MethodsThe flow cytometry analysis of CD80 and CD86 as M1-specific markers confirmed the polarization of macrophages derived from THP-1 cells. After exosome isolation, characterization, and internalization, THP-1-derived M1 macrophages were treated with SHED-MSC-EXOs. M1-specific markers and pro- and anti-oxidant indexes were evaluated. For in-silico analysis of SHED-MSC-EXOs miRNAs, initial miRNA array data of SHED-EXOs is collected from GEO, and the interaction of the miRNAs in M1 macrophage polarization (M1P), mitochondrial oxidative stress (MOS) and LPS-induced oxidative stress (LOS) were analyzed by miRWalk 3.0 server. Outcomes were filtered by 75th percentile signal intensity, score cut-off ≥0.95, minimum free energy (MEF)≤ −20 kcal/mol, and seed = 1. ResultsIt shows a decrease in the expression of CD80 and CD81, a reduction in pro-oxidant indicators, and an increase in the anti-oxidant indexes (P < 0.05). Computational analysis showed that eight microRNAs of SHED-MSC-EXO miRNAs can bind to and interfere with the expression of candidate genes in the M1P, MOS, and LOS pathways simultaneously. ConclusionSHED-MSCs-EXOs can be utilized to treat conditions related to M1 macrophage-induced diseases (M1IDs) due to their unique physical properties and ability to penetrate target cells easily.

Comparison of Solar Multifrequency Microwave Data with Other Solar Indices for Understanding Solar and Stellar Microwave Data

Thermal microwave emissions detected from stellar atmospheres contain information on stellar activity. However, even for the Sun, the relationship between multifrequency microwave data and other activity indices remains unclear. We investigated the relationships among the thermal microwave fluxes with 1, 2, 3.75, and 9.4 GHz, their circular polarizations, and several activity indices recorded during recent solar cycles and observed that these relationships can be categorized into two groups. In the first group, the relationship between the microwave fluxes and solar indices, which are strongly related to the active regions, can be well-fitted by using a linear function. In the second group, the fitting function is dependent on frequency. Specifically, the microwave fluxes at 1 and 2 GHz can be well-fitted to the total unsigned magnetic and extreme ultraviolet fluxes by employing a power-law function. The trend changes around 3.75 GHz, and the trend for the 9.4 GHz fluxes can be fitted by using a linear function. For the first time, we present the relationship between circular polarization and solar indices. Moreover, we extrapolated these relationships of the solar microwave fluxes to higher values and compared them with the solar-type stars. We found that ϵ Eri, whose microwave emission originates from thermal plasma, follows the extrapolated relationship. However, to date, only one star’s emission at 1–10 GHz has been confirmed as thermal emission. More solar-type stars should be observed with future radio interferometers to confirm that relationships based on solar data can be applied to stellar microwave data.

Statistical Features of Polar Cap North and South Indices in Response to Interplanetary and Terrestrial Conditions: A Revisit

AbstractIn this study, we investigate statistical features of polar cap north (PCN) and south (PCS) indices in response to various interplanetary conditions (interplanetary magnetic field [IMF] orientation in three‐dimensions) and terrestrial conditions (seasonal and magnetic local time [MLT] locations of the index stations). The concurrent PCN‐PCS pairs for 1998–2002 and 2004–2018 are divided based on their sign type (positive‐positive, negative‐negative, negative‐positive, and positive‐negative PCN‐PCS pairs) and time coverage (the times when both index stations are in the dawn/dusk MLT sector during northern summer/winter). Analyzing the IMF orientation dependence on the occurrence probabilities of concurrent indices and on the differences between the indices in various sign types for each time coverage reveals that the statistical features in PCN‐PCS pairs obtained in the dawn MLT sector can be largely explained by the effects of the three‐component IMF (related to the polar cap convection patterns) combined with season (related to the hemispheric asymmetry in solar illumination‐induced ionospheric conductance). However, those obtained in the dusk MLT sector are controlled dominantly by seasonal effects rather than IMF orientation effects. Our findings indicate that PCN‐PCS pair data provide local views about the solar wind‐magnetosphere‐ionosphere (SW‐M‐I) coupling system with different control efficiencies of IMF orientation and season depending on the MLT location of the stations. Therefore, introducing polar cap indices recorded simultaneously at various locations in both hemispheres and analyzing them are strongly required to infer global views of the coupled SW‐M‐I system in the open field regions with higher confidence.

Effect of phase decomposition on the mechanical properties of Ti-Zr-Nb-Ta-Mo multi-principal element alloys

Body-centered cubic Ti-Zr-Nb-Ta-Mo multi-principal element alloys (MPEAs), boasting a yield strength exceeding one gigapascal, emerge as promising candidates for demanding structural applications. However, their limited tensile ductility at room temperature presents a significant challenge to their processability and large-scale implementation. This study identifies phase decomposition as a critical factor influencing the plasticity of these alloys. The microscale phase decomposition in these MPEAs during solidification, driven by miscibility gaps, manifests as dendritic structures within grains. Closer examination reveals that the MPEAs with a pronounced thermodynamic propensity for phase decomposition are also susceptible to analogous phenomena at the atomic level. The atomic phase decomposition is characterized by the localized aggregation of some elements across nanometric domains, culminating in the establishment of short-range orderings (SROs). It is observed that phase decomposition for these MPEAs, occurring at both microscale and atomic scale, adheres to thermodynamic principles and can be predicted using the CALPHAD approach. The impact of phase decomposition on the plasticity of MPEAs fundamentally stems from the induced heterogeneities at three distinct levels: (1) Fluctuations in mechanical properties at the micron scale; (2) Variations in the strain field at the atomic scale; (3) Bond polarization and bond index fluctuations at the electronic scale. Consequently, the key to designing high-strength and high-plasticity MPEAs lies in maximizing lattice distortion while simultaneously minimizing the adverse effects of phase decomposition on the alloy's plasticity (grain boundary cohesion). This research not only clarifies the mechanisms underpinning the ductile-to-brittle transition in high-strength Ti-Zr-Nb-Ta-Mo MPEAs but also offers crucial guidelines for developing advanced, high-performance alloys.

Abstract 1128: Association between gut microbial change and acute gastrointestinal toxicity in patients with prostate cancer undergoing definitive radiation therapy

Abstract Purpose: This prospective cohort study investigated the association between gut microbial changes and acute gastrointestinal toxicities in prostate cancer patients undergoing definitive radiation therapy (RT). Methods: Seventy-nine fecal samples were analyzed. Stool samples were collected at the following timepoints: pre-RT (prRT), 2 weeks after the start of RT (RT-2w), 5 weeks after the start of RT (RT-5w), 1 month after completion of RT (poRT-1m), and 3 months after completion of RT (poRT-3m). We computed the microbial community polarization index (MCPI) as an indicator of RT-induced dysbiosis. Results: Patients experiencing toxicity had lower alpha diversity, especially at RT-2w (P=0.037) and RT-5w (P=0.003). Compared to patients without toxicity, the MCPI in those experiencing toxicities was significantly elevated (P=0.019). In terms of predicted metabolic pathways, we found linearly decreasing pathways including carbon fixation pathways in prokaryotes (P=0.035) and the bacterial secretion system (P=0.005), in patients who experienced toxicities. Conclusions: We showed RT-induced dysbiosis among patients who experienced toxicities. Reduced diversity and elevated RT-related MCPI could be helpfully used for developing individualized RT approaches. Citation Format: Bum-Sup Jang, Dong Soo Lee. Association between gut microbial change and acute gastrointestinal toxicity in patients with prostate cancer undergoing definitive radiation therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1128.