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•Contaminated shooting range soil represent a long-term source of Sb and Pb.•Antimony in porewater of shooting range soil occurred mainly as Sb(V).•Fe-based amendments successfully ...immobilized Sb and Pb over a four-year period.
Small-arm shooting ranges often receive a significant input of lead (Pb), copper (Cu) and antimony (Sb) from ammunition. The goal of the present study was to investigate the mobility, distribution and speciation of Pb and Sb pollution under field conditions in both untreated and sorbent-amended shooting range soil. Elevated Sb (19–349μgL−1) and Pb (7–1495μgPbL−1) concentrations in the porewater of untreated soil over the four-year test period indicated a long-term Sb and Pb source to the adjacent environment in the absence of remedial measures.
Mixing ferric oxyhydroxide powder (CFH-12) (2%) together with limestone (1%) into the soil resulted in an average decrease of Sb and Pb porewater concentrations of 66% and 97%, respectively. A similar reduction was achieved by adding 2% zerovalent iron (Fe°) to the soil. The remediation effect was stable over the four-year experimental period indicating no remobilization. Water- and 1M NH4NO3-extractable levels of Sb and Pb in field soil samples indicated significant immobilization by both treatments (89–90% for Sb and 89–99% for Pb). Results from sequential extraction analysis indicate fixation of Sb and Pb in less accessible fractions like amorphous iron oxides or even more crystalline and residual mineral phases, respectively. This work shows that amendment with Fe-based sorbents can be an effective method to reduce the mobility of metals both in cationic and anionic form in polluted shooting range soil.
To compare surgical success, postoperative intraocular pressure and complication rates between trabeculectomy and XEN gelstent surgery in a cohort of glaucoma patients in a typical clinical setting.
...A retrospective cohort study of consecutive patients with refractory open-angle glaucoma including patients who underwent either stand-alone XEN gelstent insertion with Mitomycin C or trabeculectomy with Mitomycin C between 2016 and 2018 at the University Eye Hospital Mainz, Germany. Primary outcome measure was the proportion of surgical success 1 year after surgery. Patients with an IOP ≤18mmHg, an intraocular pressure reduction of >20% and in no need of revision surgery or topical medication were considered a complete surgical success. If topical therapy was necessary, they were considered a qualified success. Multivariable logistic regression analysis was carried out for the primary outcome including gender, age, preoperative intraocular pressure and number of medication classes used preoperatively as adjustment variables.
171 eyes of 144 patients were included, including 82 eyes of 58 patients in the XEN group and 89 eyes of 86 patients in the trabeculectomy group. The primary outcome defined as the proportion of surgical success after 1 year (mean 11.1 months ± 2.2) was similar for both groups. The complete success proportion was 65.5% (95%-CI: 55.6-75.9%) in the trabeculectomy group, and 58.5% (95%-CI: 47.6-69.4%) in the XEN group and not statistically different in our analysis model (crude OR = 0.61; 95%-CI: 0.31-1.22; adjusted OR = 0.66; 95%-CI: 0.32-1.37). The intraocular pressure reduction, as secondary outcome measure, was higher in the trabeculectomy group (10.5 mmHg) compared to the XEN group (7.2 mmHg; p = 0.003) at the 12-month follow-up.
Both XEN gelstent implantation and trabeculectomy show similar proportions of surgical success and of complications and are therefore both recommendable for clinical routine. However, trabeculectomy seems to be more effective in lowering intraocular pressure than the XEN implantation. A prospective randomized clinical trial is necessary to evaluate differences in the long-term clinical outcome.
Brain derived neurotrophic factor (BDNF) and its receptor tropomyosin kinase receptor B (TRKB) are key regulators of activity‐dependent plasticity in the brain. TRKB is the target for both slow‐ and ...rapid‐acting antidepressants and BDNF–TRKB system mediates the plasticity‐inducing effects of antidepressants through their downstream targets. Particularly, the protein complexes that regulate the trafficking and synapse recruitment of TRKB receptors might be crucial in this process. In the present study, we investigated the interaction of TRKB with the postsynaptic density protein 95 (PSD95). We found that antidepressants increase the TRKB:PSD95 interaction in adult mouse hippocampus. Fluoxetine, a slow‐acting antidepressant, increases this interaction only after a long‐term (7 days) treatment, while (2R,6R)‐hydroxynorketamine (RHNK), an active metabolite of rapid‐acting antidepressant ketamine, achieves this within a short treatment regimen (3 days). Moreover, the drug‐induced changes of TRKB:PSD95 interaction correlate with drug latency in behaviour, observed in mice subjected to an object location memory test (OLM). While silencing of PSD95 by viral delivery of shRNA in hippocampus abolished the RHNK‐induced plasticity in mice in OLM, overexpression of PSD95 shortened the fluoxetine latency. In summary, changes in the TRKB:PSD95 interaction contribute to differences observed in drug latency. This study sheds a light on a novel mechanism of action of different classes of antidepressants.
The latencies of fluoxetine and 2R,6R‐hydroxynorketamine observed in object location memory task follow the pattern of TRKB:PSD95 interaction.
Faster enhancement of TRKB:PSD95 interaction by 2R,6R‐hydroxynorketamine compared with fluoxetine might be one of the reasons why fluoxetine requires longer time to induce its plastic effects.
The long shadow Alexander, Karl; Entwisle, Doris; Olson, Linda
Russell Sage Foundation,
2014, 20140531, 2014-06-00
eBook, Book
Contents: - The long shadow and urban disadvantageUrban disadvantage at the outset : the Baltimore backdrop. - Urban disadvantage as family disadvantage. - Stepping outside : urban disadvantage in ...neighborhood and school. - Transitioning to adulthood. - Socioeconomic destinations : the BSSYP a quarter century later. - The long shadow realized : status attainment in the BSSYP. - Race and gender stratification in urban disadvantage. - The reproduction of urban disadvantage.
This work presents an updated experimental and kinetic modeling study of n-heptane oxidation. In the experiments, ignition delay times of stoichiometric n-heptane/air mixtures have been measured in ...two different high-pressure shock tubes in the temperature range of 726–1412K and at elevated pressures (15, 20 and 38bar). Meanwhile, concentration versus time profiles of species have been measured in a jet-stirred reactor at atmospheric pressure, in the temperature range of 500–1100K at φ=0.25, 2.0 and 4.0. These experimental results are consistent with those from the literature at similar conditions and extend the current data base describing n-heptane oxidation.
Based on our experimental observations and previous modeling work, a detailed kinetic model has been developed to describe n-heptane oxidation. This kinetic model has adopted reaction rate rules consistent with those recently developed for the pentane isomers and for n-hexane. The model has been validated against data sets from both the current work and the literature using ignition delay times, speciation profiles measured in a jet-stirred reactor and laminar flame speeds over a wide range of conditions. Good agreement is observed between the model predictions and the experimental data. The model has also been compared with several recently published kinetic models of n-heptane and shows an overall better performance. This model may contribute to the development of kinetic mechanisms of other fuels, as n-heptane is a widely used primary reference fuel. Since the sub-mechanisms of n-pentane, n-hexane and n-heptane have adopted consistent reaction rate rules, the model is more likely to accurately simulate the oxidation of mixtures of these fuels. In addition, the successful implementation of these rate rules have indicated the possibility of their application for the development of mechanisms for larger hydrocarbon fuels, which are of great significance for practical combustion devices.
Prior research has demonstrated that summer learning rooted in family and community influences widens the achievement gap across social lines, while schooling offsets those family and community ...influences. In this article, we examine the long-term educational consequences of summer learning differences by family socioeconomic level. Using data from the Baltimore Beginning School Study youth panel, we decompose achievement scores at the start of high school into their developmental precursors, back to the time of school entry in 1st grade. We find that cumulative achievement gains over the first nine years of children's schooling mainly reflect school-year learning, whereas the high SES-low SES achievement gap at 9th grade mainly traces to differential summer learning over the elementary years. These early out-of-school summer learning differences, in turn, substantially account for achievement-related differences by family SES in high school track placements (college preparatory or not), high school noncompletion, and four-year college attendance. We discuss implications for understanding the bases of educational stratification, as well as educational policy and practice.
Student flow visualization Loder, Alexander Karl Ferdinand
European journal of education,
June 2024, 2024-06-00, 20240601, Letnik:
59, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Universities aim at increasing student retention, with evidence‐based and data‐based governance of universities becoming best practice. In this context, managing large amounts of data in university ...management is a challenge. Sankey diagram visualizations of student flows per time unit (e.g. semesters) have been used as method for structuring but lacked the ability to go beyond program level. This study aims to advance this method by displaying multiple student lifecycles from school to doctorate, while including user‐based input. Data of 83,264 students enrolled into 140,593 programs between 2012/13 and 2022/23 with 657.615 distinct rows in the raw data were used. A self‐synchronizing web interface was provided, including filter and stratification variables. The diagrams could be mapped to students' lifecycles and extended over all degree levels and fields of study. Limitations were data availability and the lack of indicators for each stage of the student lifecycle. Improvements in the mapping are warranted.
To evaluate whether anterior segment anatomy and axial length are associated with prematurity and perinatal factors in adults.
The Gutenberg Prematurity Eye Study examined adults born preterm and ...term aged 18-52 years. All participants underwent a prospective ophthalmic examination (optical biometry via a LenStar 900, Haag-Streit) in Germany. The associations between gestational age (GA), birth weight (BW) and BW percentile, retinopathy of prematurity (ROP) occurrence, ROP treatment and other perinatal factors with the main outcome measures were evaluated by univariate and multivariable linear regression analyses. Main outcome measures were corneal radius, white-to-white distance, anterior chamber depth, lens thickness and axial length.
The study involved 861 eyes of 438 preterm and full-term individuals (aged 28.6±8.7 years, 245 females,). After adjustment for age and gender, a steeper corneal radius was associated with lower GA (B=0.02; p<0.001) and a lower BW percentile (B=0.003; p<0.001). A smaller white-to-white distance was linked to lower GA (B=0.02; p<0.001), a lower BW percentile (B=0.004; p<0.001) and postnatal ROP occurrence (B=-0.26; p<0.001). Decreased axial length was associated with lower GA at birth (B=0.05; p=0.002) and pre-eclampsia (B=-0.34; p=0.015). ROP-treated eyes had a shallower anterior chamber depth (B=-0.63; p=0.001) and increased lens thickness (B=0.64, p<0.001).
Our analyses in adults demonstrate that the corneal morphology is influenced by GA and BW percentile, while the anterior chamber depth and lens thickness are affected by ROP treatment, namely laser therapy and cryotherapy. The present study highlights that perinatal factors lead to lifelong sequelae of ocular shape.
This study expands the existing methods for non-destructively identifying the spatially varying material properties of a structure using modal data. It continues a recently published approach to this ...inverse problem that employed Bayesian inference in conjunction with the Karhunen-Loève expansion to solve it. Here, we present two developments. Firstly, eigenvectors are used instead of eigenvalues, improving the results significantly. Secondly, a generalized polynomial chaos surrogate accelerates the inversion procedure. Finally, we develop a methodology for reusing the surrogate model across inversion tasks. We demonstrate the efficacy and efficiency of this methodology via the field of additive manufacturing and the fused deposition modeling process. The good results promise profound computational cost saving potential for large-scale applications.
•Bayesian inference of spatially varying elastic material properties using modal data.•Dimensionality reduction employing the Karhunen-Loève expansion.•Acceleration of finite element model via generalized polynomial chaos.•Application demonstration for functionally graded materials.•Recycling of the surrogate for changing length-scales based on transformations.
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