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Dy3+, Ce3+ co-doped KY(CO3)2 phosphors with a monoclinic structure were synthesized using the hydrothermal method to create a fixed yellow-to-blue ratio emission. The [YO8] polyhedron, consisting of a Y atom and eight oxygen atoms, forms a relatively independent microstructure within the KY(CO3)2 host. Y3+ ions are partially replaced by Ce3+ or Dy3+ ions to construct the [CeO8] or [DyO8] polyhedral fluorescence emission unit. The spectral measurements indicate that Ce3+ and Dy3+ can maintain relatively independent fluorescence emission characteristics in the KY(CO3)2 host. The yellow-to-blue intensity ratio of Dy3+ remains close to 1 and does not change with the variation in the doping concentration of KY(CO3)2:Dy3+ and KY(CO3)2:Dy3+,Ce3+ phosphors. When Ce3+ and Dy3+ are co-doped with KY(CO3)2, the emission intensities of Dy3+ under 339 nm and 365 nm excitation increase by 8.43 and 2.32 times, respectively, through resonance energy transfer and cross-relaxation. All Ce3+-doped KY(CO3)2:Dy3+ phosphors can emit white light. Among them, the emitted light of KY(CO3)2:3%Dy3+,5%Ce3+ is closest to standard daylight. Therefore, a stable [YO8] polyhedral structure can be used to achieve more color tuning of light. [ABSTRACT FROM AUTHOR]

The problem of registering point clouds in scenarios with low overlap is explored in this study. Previous methodologies depended on having a sufficient number of repeatable keypoints to extract correspondences, making them less effective in partially overlapping environments. In this paper, a novel learning network is proposed to optimize correspondences in sparse keypoints. Firstly, a multi-layer channel sampling mechanism is suggested to enhance the information in point clouds, and keypoints were filtered and fused at multi-layer resolutions to form patches through feature weight filtering. Moreover, a template matching module is devised, comprising a self-attention mapping convolutional neural network and a cross-attention network. This module aims to match contextual features and refine the correspondence in overlapping areas of patches, ultimately enhancing correspondence accuracy. Experimental results demonstrate the robustness of our model across various datasets, including ModelNet40, 3DMatch, 3DLoMatch, and KITTI. Notably, our method excels in low-overlap scenarios, showcasing superior performance. [ABSTRACT FROM AUTHOR]

Phosphors with a longer excitation wavelength exhibit higher energy conversion efficiency. Herein, quantum cutting KGd(CO3)2:Tb3+ phosphors excited by middle-wave ultraviolet were synthesized via a hydrothermal method. All the KGd(CO3)2:xTb3+ phosphors remain in monoclinic structures in a large Tb3+ doping range. In the KGd(CO3)2 host, 6D3/2 and 6I17/2 of Gd3+ were employed for quantum cutting in sensitizing levels. The excited state electrons could easily transfer from Gd3+ to Tb3+ with high efficiency. There are three efficient excited bands for quantum cutting. The excited wavelengths of 244, 273, and 283 nm correspond to the transition processes of 8S7/2→6D3/2 (Gd3+), 8S7/2→6I17/2 (Gd3+), and 7F6→5F4 (Tb3+), and the maximum quantum yields of KGd(CO3)2:Tb3+ can reach 163.5, 119, and 143%, respectively. The continuous and efficient excitation band of 273–283 nm can well match the commercial 275 nm LED chip to expand the usage of solid-state light sources. Meanwhile, the phosphor also shows good excitation efficiency at 365 nm in a high Tb3+ doping concentration. Therefore, KGd(CO3)2:Tb3+ is an efficient green-emitting phosphor for ultraviolet-excited solid-state light sources. [ABSTRACT FROM AUTHOR]

The ENSO impact on winter precipitation in the Southeast United States was analyzed from the perspective of daily weather types (WTs). We calculated the dynamic contribution associated with the change in frequency of the WTs and the thermodynamic contribution due to changes in the spatial patterns of the environmental fields of the WTs. Six WTs were obtained using a k-means clustering analysis of 850 hPa winds in reanalysis data from November to February of 1948–2022. All the WTs can only persist for a few days. The most frequent winter weather type is WT1 (shallow trough in Eastern U.S.), which can persist or likely transfer to WT4 (Mississippi River Valley ridge). WT1 becomes less frequent in El Niño years, while the frequency of WT4 does not change much. WTs 2–6 correspond to a loop of eastward propagating waves with troughs and ridges in the mid-latitude westerlies. Three WTs with a deep trough in the Southeast U.S., which are WT2 (east coast trough), WT3 (off east coast trough) and WT6 (plains trough), become more frequent in El Niño years. The more frequent deep troughs (WTs 2, 3 and 6) and less frequent shallow trough (WT1) result in above-normal precipitation in the coastal Southeast U.S. in the winter of El Niño years. WT5 (off coast Carolina High), with maximum precipitation extending from Mississippi Valley to the Great Lakes, becomes less frequent in El Niño years, which corresponds to the below-normal precipitation from the Great Lakes to Upper Mississippi and Ohio River Valley in El Niño years, and vice versa in La Niña years. The relative contribution of the thermodynamic and dynamic contribution is location dependent. On the east coast, the two contributions are similar in magnitude. [ABSTRACT FROM AUTHOR]

A non-absorbable therapeutic candidate for the treatment of hyperammonemia has been identified and characterized. Conventional approaches to reducing ammonia concentration in the blood and colon include acidifying the colon, inhibiting the bacterial production of ammonia, and activation of the urea cycle. Addressing gaps in the literature around therapeutic ammonia adsorption, this study established assays for ammonia uptake from both NH4OH and NH4Cl solutions as well as interference and selectivity for potassium absorption. Performance was characterized for a large number and variety of materials, spanning zeolites, ion-exchange resins, metallopolymers, metal–organic frameworks (MOFs), and polymeric carboxylic acids. The latter class showed low potassium capacity (poly(acrylic acid): 10 mg/g, poly(maleic-co-acrylic acid): 4 mg/g) and a therapeutically relevant depression of pH in buffered simulated intestinal fluid (SIF) (poly(acrylic acid): −2.01 and poly(maleic-co-acrylic acid): −3.23) compared to lactulose (−3.46), an approved therapeutic for hyperammonemia that works by acidifying the colon. In the polymeric organic acids evaluated, pH depression correlated well with pKa and acid site density. Additionally, this class of candidates should avoid the undesirable side effects of lactulose, such as the potential for hyperglycemia in diabetic patients and incompatible use with galactosemic patients. [ABSTRACT FROM AUTHOR]

Daily weather types (WTs) over the Southeast United States have been analyzed using 850 hPa winds from reanalysis data from March to October of 1979–2019. Six WTs were obtained. WTs 1–3 represent mid-latitude synoptic systems propagating eastward. WT4 is a summer-type pattern predominantly occurring in June–August, with the center of the North Atlantic Subtropical High (NASH) along the Gulf coast in the southern United States. WT5 is most frequent from August to middle October, with the NASH pushed further north and southerly winds over the northern Great Plains. An anticyclone centered at the Carolina coast characterizes WT6, which occurs in all months but is slightly more frequent in the spring and fall, especially in October, corresponding to fair weather in the region. WTs 1, 2 and 3 can persist for only a few days. WTs 4, 5 and 6 can have long spells of persistence. Besides self-persistence, the most observed progression loop is WT1 to WT2, to WT3, and then back to WT1, corresponding to eastward-propagating waves. WTs 4 and 5 are likely to show persistence, with long periods of consecutive days. WT6 usually persists but can also transfer to WT3, i.e., a change from fair weather in the Southeast U.S. to rainy weather in the Mississippi River Valley. A diurnal cycle of precipitation is apparent for each WT, especially over coastal plains. The nocturnal precipitation in central U.S. is associated with WT3. WTs 1–3 are more frequent in El Niño years, corresponding to stronger westerly wave activities and above normal rainfall in the Southeast U.S. in the spring. The positive rainfall anomaly in the Mississippi and Ohio River valley in El Niño years is also associated with more frequent WT3. [ABSTRACT FROM AUTHOR]

Sea breezes have been observed to move inland over 100 km. These airmasses can be markedly different from regional airmasses, creating a shallow layer with differences in humidity, wind, temperature and aerosol characteristics. To understand their influence on boundary layer and cloud development on subsequent days, we identify their frequency and characteristics. We visually identified sea breeze fronts on radar passing over the Savannah River Site (SRS) between March and October during 2015–2019. The SRS is ~150 km from the nearest coastal location; therefore, our detection suggests further inland penetration. We also identified periods when sea breeze fronts may have passed but were not visually observed on radar due to the shallow sea breeze airmass remaining below the radar beam elevation that ranges between approximately 1–8 km depending on the beam angle and radar source (Columbia, SC or Charleston, SC). Near-surface atmospheric measurements indicate that the dew point temperature increases, the air temperature decreases, the variation in wind direction decreases and the aerosol size increases after sea breeze frontal passage. A synoptic classification procedure also identified that inland moving sea breezes are more commonly observed when the synoptic conditions include weak to moderate offshore winds with an average of 35 inland sea breezes occurring each year, focused primarily in the months of April, May and June. [ABSTRACT FROM AUTHOR]