First observation of bright solitons in bulk superfluid He-4

The existence of bright solitons in bulk superfluid He-4 is demonstrated by time-resolved shadowgraph i maging experiments and density functional theory (DFT) calculations. The initial liquid compression that leads to the creation of non-linear waves is produced by rapidly expanding plasma from laser ablation. Af ter the leading dissipative period, these waves transform into bright solitons, which exhibit three chara cteristic features: dispersionless propagation, negligible interaction in two-wave collision, and direct dependence between soliton amplitude and the propagation velocity. The experimental observations are supp orted by DFT calculations, which show rapid evolution of the initially compressed liquid into bright soli tons. At high amplitudes, solitons become unstable and break down into dispersive shock waves.Comment: 5 pages, 6 figures (accepted for publication in Phys. Rev. Lett.

Where does the lactate come from? A rare cause of reversible inhibition of mitochondrial respiration

Biguanide poisoning is associated with lactic acidosis. The exact mechanism of biguanide-induced lactic acidosis is not well understood. In the previous issue of Critical Care, Protti and colleagues demonstrated that biguanide-induced lactic acidosis may be due in part to a reversible inhibition of mitochondrial respiration. Thus, in the absence of an antidote, increased drug elimination through dialysis is logical

Pro-Environmental Attitudes and Behaviors in Higher Education: Investigating the Role of Formal and Informal Factors

Scholars have documented the growing presence of environmental and sustainability education in higher education institutions around the world. However, we know little about how colleges and universities mobilize students to adopt pro-environmental attitudes and behaviors. Drawing on the whole student framework, this study examines the extent to which curricular and co-curricular factors are associated with students’ engagement with environmentalism. Using survey data from 539 students at Indiana University and multivariate analysis, we demonstrate that (a) hearing about environmentalism and sustainability in class and (b) membership in campus-based environmental groups have positive and significant effects. These factors are associated with increased levels of care for the environment and increased levels of private and public pro-environmental behaviors. We discuss the implications of these findings in relation to the role of higher education institutions as incubators for the development of competent social actors

Black Power, Inc.: Global American Business and the Post-Apartheid City

Black Power, Inc.: Global American Business and the Post-Apartheid City explains the rise of black empowerment in the United States and southern Africa during the late twentieth-century. Black empowerment, defined as private and government programs promoting job-training, community development, and black entrepreneurship, flourished in the late 1960s and 1970s as a popular response to social unrest in black neighborhoods from North Philadelphia to Soweto. “Black Power, Inc.” analyzes the intellectual and financial investments made by American businesspeople, government bureaucrats, and black entrepreneurs in transforming black dissidents into “productive citizens” in an economic and civic sense. As these efforts spread, the transnational discourse of black empowerment intersected and appropriated a global Black Power politics. My project draws attention to the contestations between Black Power and black empowerment advocates across the diaspora. Drawing on corporate and “movement” records from the United States and South Africa, I reveal the connections between black internationalism and the post-war globalization of American capitalism in ways too often obscured by the separation of Business History and Global Black Studies. By prioritizing private capital, I furthermore explain Black Power’s demise in a way that reveals the seeds of political conservatism that blossomed within the global black freedom struggle

Effects of Estrogen Loss on the Vascular Porosity in Rat Cortical Bone

Osteoporosis is a skeletal disease that currently affects 10 million Americans, and is characterized by low bone mass and increased skeletal fragility (National Osteoporosis Foundation, 2011). Estrogen loss, which begins during menopause, is the leading cause of osteoporosis in women. Recent research has focused on changes in cortical bone microporosity due to estrogen loss, which is important for bone health; load-induced interstitial fluid flow within the lacunar-canalicular porosity surrounding osteocytes is thought to play an important role in bone maintenance, while the vascular porosity provides a pressure relaxation mechanism for the fluid flow in the lacunar-canalicular porosity. Recent high-resolution micro-CT studies show that the cortical vascular porosity and average vascular canal diameter increase in the tibia metaphysis of ovariectomized (OVX) rats (Larriera et al., 2010). The present study investigated whether osteoclast resorption is responsible for the increased canal diameter, and if changes in the cortical blood vessel morphology occur due to estrogen loss. Alterations in the vascular porosity and bone vasculature were assessed using the rat OVX model at one and two weeks post-OVX, and analyzed histologically using TRAP enzyme and Goldner’s Trichrome staining. No differences in TRAP activity or vasculature morphology between OVX and sham-operated animals were found for all measurements one and two weeks post-surgery, signifying that osteoclast resorption may not be the primary mechanism for the increased canal diameter demonstrated previously. These results also suggest that cortical blood vessel morphology is unchanged at these time points. All parameters quantified in this thesis will be analyzed six weeks post-OVX to see if there are changes at the time point corresponding to the previous micro-CT analyses. While additional research is needed, this study begins to unveil the ways in which postmenopausal osteoporosis affects the microporosity in cortical bone

The public and private sector family planning supply environments and their influence on contraceptive use in urban Nigeria

Background: Over 50% of the world lives in an urban area. The highest rate of urban population growth is in Sub-Saharan Africa, where fertility rates remain high. To slow population growth and improve health and well-being, family planning (FP) advocates argue for increasing the use of modern FP through improved contraceptive access and availability. However, important questions remain about the best way to promote contraceptive use in countries with high fertility. Purpose: The overarching aim of this dissertation was to explore the influence of the urban public and private FP supply environments on modern contraceptive use. Methods: Data from the 2010-2011 Nigeria baseline survey conducted by the Measurement, Learning & Evaluation Project were used to create and assign aggregate level FP supply index scores to nineteen local government areas (LGAs) across six selected cities of Nigeria. It explored relationships between public and private sector FP services and determined whether contraceptive access and availability in either sector was correlated with community-level wealth. Path analysis was then used to estimate the direct effects of the supply environments on modern contraceptive use. Indirect effects were also analyzed using perception of supply as a mediating variable. Results: Data showed pronounced variability in contraceptive access and availability across LGAs in both sectors, a positive correlation between public and private sector supply environments and localized associations between the supply environments and poverty. Furthermore, after controlling for influential covariates, analyses found that a woman's perception of supply had a significant positive effect on contraceptive use, whereas her actual immediate supply environment had negligible influence. Conclusions: The distribution of contraceptive access and availability within an urban area is not a significant indicator of contraceptive use. Contraception must be available for women once (and if) they desire to use it. However, program planners and policy makers should be aware of FP market saturation. When existing demand is met, it may be most efficacious to concentrate on means of internal influence to promote FP, such as education, media and social networking, all of which help make contraceptive use an accepted, normative behavior.Doctor of Philosoph

What Primary Schools Are Doing Right: Educational Value-Added in Luxembourg

In such a diverse context as Luxembourg, educational inequalities can arise from diverse languages spoken at home, a migration background, or a family’s socioeconomic status. This diversity leads to different preconditions for learning math and languages (e.g. the language of instruction) and thus shapes the school careers of students (Hadjar & Backes, 2021). The aim of the project Systematic Identification of High Value-Added in Educational Contexts (SIVA) was to answer the questions (1) what highly effective schools are doing “right” or differently and (2) what other schools can learn from them in alleviating inequalities. In collaboration with the Observatoire National de la Qualité Scolaire, we investigated the differences of schools with stable high value-added (VA) scores to those with stable medium or low VA scores from multiple perspectives. VA is a statistical regression method usually used to fairly estimate schools’ effectiveness considering diverse student backgrounds. First, we identified 16 schools which had a stable high, medium, or low VA scores over two years. Second, we collected data on their pedagogical strategies, student background, and school climate through questionnaires and classroom observations. Third, we matched our data to results from the Luxembourg School Monitoring Programme ÉpStan (LUCET, 2021). We selected the variables based on learning models focusing on aspects such as school organization or classroom management (e.g., Hattie, 2008; Helmke et al., 2008; Klieme et al., 2001). We further investigated specificities about the Luxembourgish school system, which are not represented in international school learning models (such as the division into two-year learning cycles, the multilingual school setting, or the diverse student population). We will discuss the SIVA-project, its goals, and its data collection leading to data from observations in 49 classroom and questionnaires with over 500 second graders, their parents, their teachers, as well as school presidents and regional directors. Literature Hadjar, A., & Backes, S. (2021). Bildungsungleichheiten am Übergang in die Sekundarschule in Luxemburg. https://doi.org/10.48746/BB2021LU-DE-21A Hattie, J. (2008). Visible Learning: A synthesis of over 800 meta-analyses relating to achievement (0 ed.). Routledge. https://doi.org/10.4324/9780203887332 Helmke, A., Rindermann, H., & Schrader, F.-W. (2008). Wirkfaktoren akademischer Leistungen in Schule und Hochschule [Determinants of academic achievement in school and university]. In M. Schneider & M. Hasselhorn (Eds.), Handbuch der pädagogischen Psychologie (Vol. 10, pp. 145–155). Hogrefe. Klieme, E., Schümer, G., & Knoll, S. (2001). Mathematikunterricht in der Sekundarstufe I: “Aufgabenkultur” und Unterrichtsgestaltung. TIMSS - Impulse für Schule und Unterricht, 43–57. LUCET. (2021). Épreuves Standardisées (ÉpStan). https://epstan.l

Evaluating the Patient-Reported Outcomes Measurement Information System scales in acute intermittent porphyria.

PurposeAcute intermittent porphyria (AIP) is a rare inborn error of heme biosynthesis characterized by life-threatening acute attacks. Few studies have assessed quality of life (QoL) in AIP and those that have had small sample sizes and used tools that may not have captured important domains.MethodsBaseline data from the Porphyrias Consortium's Longitudinal Study were obtained for 259 patients, including detailed disease and medical history data, and the following Patient-Reported Outcomes Measurement Information System (PROMIS) scales: anxiety, depression, pain interference, fatigue, sleep disturbance, physical function, and satisfaction with social roles. Relationships between PROMIS scores and clinical and biochemical AIP features were explored.ResultsPROMIS scores were significantly worse than the general population across all domains, except depression. Each domain discriminated well between asymptomatic and symptomatic patients with symptomatic patients having worse scores. Many important clinical variables like symptom frequency were significantly associated with domain scores in univariate analyses, showing responsiveness of the scales, specifically pain interference and fatigue. However, most regression models only explained ~20% of the variability observed in domain scores.ConclusionPain interference and fatigue were the most responsive scales in measuring QoL in this AIP cohort. Future studies should assess whether these scales capture longitudinal disease progression and treatment response

Value-Added Scores Show Limited Stability over Time in Primary School

Value-added (VA) models are used for accountability purposes and quantify the value a teacher or a school adds to their students’ achievement. If VA scores lack stability over time and vary across outcome domains (e.g., mathematics and language learning), their use for high-stakes decision making is in question and could have detrimental real-life implications: teachers could lose their jobs, or a school might receive less funding. However, school-level stability over time and variation across domains have rarely been studied together. In the present study, we examined the stability of VA scores over time for mathematics and language learning, drawing on representative, large-scale, and longitudinal data from two cohorts of standardized achievement tests in Luxembourg (N = 7,016 students in 151 schools). We found that only 34-38% of the schools showed stable VA scores over time with moderate rank correlations of VA scores from 2017 to 2019 of r = .34 for mathematics and r = .37 for language learning. Although they showed insufficient stability over time for high- stakes decision making, school VA scores could be employed to identify teaching or school practices that are genuinely effective—especially in heterogeneous student populations.