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This work aims to clarify the relationship between the optical, particularly luminescent, characteristics of the La1-x-ySmxCayVO4-δ powder nanosized compounds with their phase composition and concentration of dopants. According to the high-accuracy XRD data, the samples are a mixture of monoclinic and tetragonal crystal phases. The diffuse reflection and photoluminescence (PL) spectra were measured and analyzed including spectral distributions and intensity ratios of the PL bands, the positions and half-widths of envelopes of the groups of lines in the PL spectra of Sm3+ ions. Estimated from the diffuse reflection data the band gap values are 3.85, and 3.82, 3.75, 3.78 eV for the samples with x = 0.1, y = 0, and (x, y) = 0.05, 0.10, 0.15, respectively. The PL excitation spectra of the La1-x-ySmxCayVO4-δ nanoparticles consist of both the wide UV wavelength band (260–360 nm) caused by transition in the VO43− molecular groups and in a set of narrow lines caused by inner f-f transitions in the Sm3+ ions (spectral range 350–520 nm). The PL spectra of the La1-x-ySmxCayVO4-δ nanoparticles contain four groups of lines (I – IV) resulting from the 4G5/2 → 6H5/2, 6H7/2, 6H9/2, and 6H11/2 transitions, respectively, in the inner f shell of the Sm3+ ions. The concentration behavior of the Sm3+ ions PL characteristics is related to the evaluation of the phase composition of La1-x-ySmxCayVO4-δ samples. It was found that the changes of the Rlum = I(III)/I(I), where I(III) and I(I) are the integrated intensities of the corresponding groups of lines, can be related to the phase composition of the La1-x-ySmxCayVO4-δ compounds. Developed in this work the combined way of structural and optical data analysis may be useful in designing other multiphase phosphor systems containing Sm3+ ions.

The (NPbPEr) glasses of the composition (20-x) Na2SO4–20PbO–60P2O5-xEr2O3 (x = 0.1, 0.3, 0.5, 0.7, 1.0 mol %) are synthesized by melt quenching process. The basic characterization studies like XRD and EDS have confirmed amorphous nature and contents of the samples. The spectroscopic studies viz., optical absorption, photoluminescence (PL) and decay profiles were carried out. The PL spectra exhibited an intense sharp green emission peak at 544 nm due to 4S3/2 → 4I15/2 transition of Er3+ ions both in down-conversion (DC, λexc = 377 nm) and up-conversion (UC, λexc = 977 nm) PL spectra. The spectra also exhibited a broad intense NIR band at 1532 nm ascribed to 4I13/2→4I15/2 transition of Er3+ ions at λexc = 977 nm. The analysis of the spectra indicated 0.5 mol% of Er2O3 is the optimal concentration for achieving maximal PL output both in the green and in NIR regions. The CIE color coordinates and the corresponding CCT (K) values were estimated from both UC and DC emission spectra. Overall analysis of the results suggested that the investigated glasses are potential candidates for getting intense green light emission and are quite suitable as optical fibre amplifiers in the green and NIR (around 1.5 μm) regions. Keywords: Sodium sulfo-phosphate glasses, Er3+ ions, Green and NIR emission

Climate change in the Arctic is predicted to drastically alter carbon and nutrient pools, plant communities, and plant–animal interactions. We examined how four levels of long-term (16 years) nutrient addition in moist acidic tundra affected plant community structure and the abundance of Eriophorum vaginatum, the preferred forage for tundra voles (Microtus oeconomus). We also explored how simulated press and pulse herbivory for four years affected Eriophorum at these different nutrient levels. Shifts in plant community structure, reductions in species diversity and richness, and decreased Eriophorum abundance were pronounced at the highest levels of nutrient addition. Eriophorum abundance was negatively correlated with deciduous shrub abundance, likely caused by light limitation in fertilized plots. Added nutrients generally increased Eriophorum leaf length, but effects varied among years and simulated herbivory treatments. After being clipped once, Eriophorum leaves regrew in fertilized plots to the same length as leaves that had not been clipped, demonstrating recovery. Our results show how interannual variation in plant growth and animal activity might exacerbate or dampen responses over multiple years. Changes to plant community composition and plant–vole interactions associated with increased soil nutrients resulting from warming could have cascading impacts on arctic ecosystems and carbon cycling.

It is a well-established experimental fact that exciton-phonon coupling is very efficient in ZnO. The intensities of the phonon-replicas in ZnO/(ZnMg)O quantum structures strongly depend on the internal electric field. We performed high-pressure measurements on the single ZnO/(ZnMg)O quantum well. We observed a strong increase of the intensity of the phonon-replicas relative to the zero phonon line. In our opinion this effect is related to pressure induced increase of the strain in quantum structure. As a consequence, an increase of the piezoelectric component of the electric field is observed which leads to an increase of the intensity of the phonon-replicas.

The documentation of cultural heritage objects requires a special approach, as does the collection of materials describing a monument over a period of time. With the development of measurement and information technologies, such documentation can be supplemented by a digital model of the object, a 3D visualization in a computer environment, or a miniature, scaled 3D printout. This paper presents a methodology for developing the 3D documentation of the Monument to the Polish Diaspora Bond with the Homeland, a sculpture located in Koszalin, Poland. In the study, terrestrial laser scanning supplemented with photos was used for non-invasive measurements, and existing free software was used to generate a 3D model. The results of the study can supplement the technical documentation of an object so as to preserve its characteristic features and ease the conservation of monuments. The proposed approach to modelling 3D monuments can be used to create HBIM documentation.

This study explores the intersection of waste management and sustainable fuel production, focusing on the pyrolysis of plastic waste, specifically polystyrene. We examine the physicochemical parameters of the resulting waste plastic pyrolytic oils (WPPOs), blended with kerosene to form a potential alternative fuel for gas turbines. Our findings reveal that all WPPO blends lead to increased emissions, with NOX rising by an average of 61% and CO by 25%. Increasing the proportion of WPPO also resulted in a higher exhaust gas temperature, with an average rise of 12.2%. However, the thrust-specific fuel consumption (TSFC) decreased by an average of 13.8%, impacting the overall efficiency of waste-derived fuels. This study underscores the need for integrated waste-to-energy systems, bridging the gap between waste management and resource utilization.

Abstract The Gila robusta species complex in the lower reaches of the Colorado River includes three nominal and contested species (G. robusta, G. intermedia, and G. nigra) originally defined by morphological and meristic characters. In subsequent investigations, none of these characters proved diagnostic, and species assignments were based on capture location. Two recent studies applied conservation genomics to assess species boundaries and reached contrasting conclusions: an ezRAD phylogenetic study resolved 5 lineages with poor alignment to species categories and proposed a single species with multiple population partitions. In contrast, a dd-RAD coalescent study concluded that the three nominal species are well-supported evolutionarily lineages. Here we developed a draft genome (~ 1.229 Gbp) to apply genome-wide coverage (10,246 SNPs) with nearly range-wide sampling of specimens (G. robusta N = 266, G. intermedia N = 241, and G. nigra N = 117) to resolve this debate. All three nominal species were polyphyletic, whereas 5 of 8 watersheds were monophyletic. AMOVA partitioned 23.1% of genetic variance among nominal species, 30.9% among watersheds, and the Little Colorado River was highly distinct (F ST ranged from 0.79 to 0.88 across analyses). Likewise, DAPC identified watersheds as more distinct than species, with the Little Colorado River having 297 fixed nucleotide differences compared to zero fixed differences among the three nominal species. In every analysis, geography explains more of the observed variance than putative taxonomy, and there are no diagnostic molecular or morphological characters to justify species designation. Our analysis reconciles previous work by showing that species identities based on type location are supported by significant divergence, but natural geographic partitions show consistently greater divergence. Thus, our data confirm Gila robusta as a single polytypic species with roughly a dozen highly isolated geographic populations, providing a strong scientific basis for watershed-based future conservation.

The field of medical technology has undergone significant advancements over the years, from the use of ancient scalpels, forceps, and sutures to complex devices like intraoperative MRI suites, artificial intelligence-enabled monitors, and robotic surgical systems. These advancements have had a profound impact on the way we diagnose, treat, and prevent diseases, and have significantly improved the quality of life for millions of people around the world. As we move forward, it is important to reflect on the direction of medical technology and consider the potential risks and benefits of new advancements. We must also ensure that these technologies are accessible to all and that they are used ethically and responsibly. There is still much to be discovered and developed in the field of medical technology, and it is up to us to ensure that we are moving in a positive direction that benefits everyone.

Abstract Background One of the seminal events since 2019 has been the outbreak of the SARS-CoV-2 pandemic. Countries have adopted various policies to deal with it, but they also differ in their socio-geographical characteristics and public health care facilities. Our study aimed to investigate differences between epidemiological parameters across countries. Method The analysed data represents SARS-CoV-2 repository provided by the Johns Hopkins University. Separately for each country, we estimated recovery and mortality rates using the SIRD model applied to the first 30, 60, 150, and 300 days of the pandemic. Moreover, a mixture of normal distributions was fitted to the number of confirmed cases and deaths during the first 300 days. The estimates of peaks’ means and variances were used to identify countries with outlying parameters. Results For 300 days Belgium, Cyprus, France, the Netherlands, Serbia, and the UK were classified as outliers by all three outlier detection methods. Yemen was classified as an outlier for each of the four considered timeframes, due to high mortality rates. During the first 300 days of the pandemic, the majority of countries underwent three peaks in the number of confirmed cases, except Australia and Kazakhstan with two peaks. Conclusions Considering recovery and mortality rates we observed heterogeneity between countries. Liechtenstein was the “positive” outlier with low mortality rates and high recovery rates, at the opposite, Yemen represented a “negative” outlier with high mortality for all four considered periods and low recovery for 30 and 60 days.

Objective: This study evaluates whether patients residing in expansion states have a greater increase in outpatient diagnoses of acute diabetes complications than those living in non-expansion states following the implementation of the Affordable Care Act (ACA). Methods: This retrospective cohort study uses electronic health records (EHR) from 10,665 non-pregnant patients, aged 19 to 64 years old who were diagnosed with diabetes in 2012 or 2013 from 347 community health centers (CHCs) across 16 states (11 expansion and 5 non-expansion states). Patients included had ≥1 outpatient ambulatory visit in each of these periods: pre-ACA: 2012 to 2013, post-ACA: 2014 to 2016, and post-ACA: 2017 to 2019. Acute diabetes-related complications were identified using International Classification Diseases (ICD-9-CM and ICD-10-CM) codes classification and could occur on or after diagnosis of diabetes. We performed difference-in-differences (DID) analysis using a generalized estimating equation to compare the change in rates of acute diabetes complications by year and by Medicaid expansion status. Results: There was a greater increase after year 2015 in visits related to abnormal blood glucose among patient living in Medicaid expansion states than in non-expansion states (2017 DID = 0.041, 95% CI = 0.027-0.056). Although both visits due to any acute diabetes complications and infection-related diabetes complications were higher among patients living in Medicaid expansion states, there was no difference in the trend overtime between expansion and non-expansion states. Conclusion: We found a significantly greater rate of visits for abnormal blood glucose in patients receiving care in expansion states relative to patients in CHCs in non-expansion states starting in 2015. Additional resources for these clinics, such as the ability to provide blood glucose monitoring devices or mailed/delivered medications, could substantially benefit patients with diabetes.