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Biology is perhaps the most complex of the sciences, given the incredible variety of chemical species that are interconnected in spatial and temporal pathways that are daunting to understand. Their interconnections lead to emergent properties such as memory, consciousness, and recognition of self and non-self. To understand how these interconnected reactions lead to cellular life characterized by activation, inhibition, regulation, homeostasis, and adaptation, computational analyses and simulations are essential, a fact recognized by the biological communities. At the same time, students struggle to understand and apply binding and kinetic analyses for the simplest reactions such as the irreversible first-order conversion of a single reactant to a product. This likely results from cognitive difficulties in combining structural, chemical, mathematical, and textual descriptions of binding and catalytic reactions. To help students better understand dynamic reactions and their analyses, we have introduced two kinds of interactive graphs and simulations into the online educational resource, Fundamentals of Biochemistry, a LibreText biochemistry book. One is available for simple binding and kinetic reactions. The other displays progress curves (concentrations vs. time) for simple reactions and complex metabolic and signal transduction pathways. Users can move sliders to change dissociation and kinetic constants as well as initial concentrations and see instantaneous changes in the graphs. They can also export data into a spreadsheet for further processing, such as producing derivative Lineweaver-Burk and traditional Michaelis-Menten graphs of initial velocity (v[subscript 0]) versus substrate concentration.

BackgroundCountry submission of Voluntary National Reviews is the formal mechanism to report on progress of the Sustainable Development Goals (SDGs). Despite strong political commitment to strong information systems, large data gaps exist in the Eastern Mediterranean Region.MethodsThis study aims to review reports submitted by countries in the region to assess the comprehensiveness of reporting on the health-reported SDG targets and indicators. We conducted a content analysis of reports submitted between 2016 and 2021 of 18 countries of the region. The review focused on progress on the SDGs by assessing i) the reporting on the 50 health-related targets and indicators ii) data availability using the WHO reporting framework, and iii) data availability based on source of information. Spreadsheets were developed and used to extract data and facilitate content analysis.ResultsAll reports confirmed that SDG monitoring and reporting mechanisms have been established, however, only 11 reported on all 17 SDGs and 8 explicitly mentioned country specific 2030 targets. Many reports identified data availability as a key challenge to SDG monitoring; for the health SDG, data availability ranged from 48% to 93% among the five countries reporting this figure. Comprehensiveness of reporting varied by type of indicator (maternal, child and infant mortality were the most common) and by country income level (greater reporting by high income countries).ConclusionsSignificant work remains to enhance information systems across the region to monitor progress and guide actions to achieve the health-related SDGs. Strengthening health information systems regulatory frameworks, data collection capacities including strengthening civil registration and vital statistics and population-based surveys are key steps to enhancing access to quality data which in turn can contribute to achieving the health-related SDGs.

Voluntary National Reviews are the formal mechanism for countries to report on progress and share lessons learned on SDG implementation. We assessed the Voluntary National Reviews submitted by countries in the WHO Eastern Mediterranean Region to note the reported progress on Sustainable Development Goal (SDG) implementation, the review preparation process and how health is positioned and framed to identify priorities for accelerating progress on the health-related SDGs. We extracted quantitative and qualitative data from 26 Voluntary National Reviews from 18 countries submitted during the period 2016 to January 2022. We focused on three areas: SDG implementation, the review preparation process and the positioning of health in the reviews. Three assessors conducted the data extraction based on the agreed framework according to their language of expertise (Arabic, English and French). One assessor supervised the whole process for consistency. If there was a doubt in interpretation, it was discussed and agreed among the assessors. Countries have established a mechanism for SDG implementation under high-level leadership, engaged in multistakeholder consultations, aligned and mainstreamed SDGs to national plans, and created a monitoring and review mechanism. Countries reported use of national participatory approach for the report preparation. The prioritization of both health and well-being (SDG3) and economic growth (SDG8) in the reports is unique compared to other regional and global assessments. Health was often framed around disease and health care provision without linkages to societal inequities and structural challenges. The reports indicated good progress in SDG implementation. Addressing upstream issues and the determinants of health requires the health sector to take a more strategic approach in advocating for health and well-being. Further research is needed to demonstrate how to address synergies and trade-offs of policy choices and identify the co-benefits of addressing health in the context of fiscal instability and widening inequities in the region.

While visual literacy has been identified as a foundational skill in life science education, there are many challenges in teaching and assessing biomolecular visualization skills. Among these are the lack of consensus about what constitutes competence and limited understanding of student and instructor perceptions of visual literacy tasks. In this study, we administered a set of biomolecular visualization assessments, developed as part of the BioMolViz project, to both students and instructors at multiple institutions and compared their perceptions of task difficulty. We then analyzed our findings using a mixed-methods approach. Quantitative analysis was used to answer the following research questions: (1) Which assessment items exhibit statistically significant disparities or agreements in perceptions of difficulty between instructors and students? (2) Do these perceptions persist when controlling for race/ethnicity and gender? and (3) How does student perception of difficulty relate to performance? Qualitative analysis of open-ended comments was used to identify predominant themes related to visual problem solving. The results show that perceptions of difficulty significantly differ between students and instructors and that students’ performance is a significant predictor of their perception of difficulty. Overall, this study underscores the need to incorporate deliberate instruction in visualization into undergraduate life science curricula to improve student ability in this area. Accordingly, we offer recommendations to promote visual literacy skills in the classroom.

Our climate is changing due to anthropogenic emissions of greenhouse gases from the production and use of fossil fuels. Present atmospheric levels of CO[subscript 2] were last seen 3 million years ago, when planetary temperature sustained high Arctic camels. As scientists and educators, we should feel a professional responsibility to discuss major scientific issues like climate change, and its profound consequences for humanity, with students who look up to us for knowledge and leadership, and who will be most affected in the future. We offer simple to complex backgrounds and examples to enable and encourage biochemistry educators to routinely incorporate this most important topic into their classrooms.

The number of ground motions used in nonlinear response history analysis (NRHA) determines the precision of the parameter estimates obtained in seismic performance assessments. While this issue has been extensively studied in the earthquake engineering literature, the relationship of probability model misspecification to parameter estimation uncertainty, and the implication to the required number of ground motions needed for NRHA, has not been examined. Probability model misspecification has the potential to increase estimation uncertainty and hence requires a greater number of ground motions to achieve the same precision compared to when misspecification is disregarded. This study develops a procedure to determine the required number of ground motions in seismic code-prescriptive and risk-based assessments with possible probability model misspecification. Specifically, we employ the quasi-maximum likelihood estimation (QMLE), which is robust to probability model misspecification, to evaluate estimation uncertainty. The QMLE approach is applied to an archetype California bridge under the two seismic assessment scenarios. In the code-prescriptive assessment, misspecification errors are identified for dispersion estimates of the bridge column ductility demand. In the most extreme case of the risk-based evaluation, misspecification increases the estimation uncertainty of the mean annual frequency of exceeding a limit state by as much as three times, which substantially increases the required number of ground motions. Based on the findings from this study, we advocate for the use of QMLE to detect and rectify the implications of model misspecification to estimation uncertainty and the number of ground motions used in probabilistic seismic performance assessments. [ABSTRACT FROM AUTHOR]

Failure mode identification in unreinforced masonry (URM) walls is a challenging task because of the presence of multiple damage mechanisms, including so-called hybrid modes. This paper employed a novel application of supervised and unsupervised learning to link URM wall design and mechanical properties to the failure mode. We used a database with 330 backbone curves from cyclically loaded URM walls as well as the associated images captured during the experiments. Based on the observations documented during the experiments, information on the cyclic curves, and the associated images, the walls were first manually classified into four failure modes: bed-joint sliding, diagonal tension, rocking, and toe crushing. Then k -means clustering was used to group the damaged walls into four classes based on critical points along the backbone curves. A hybridity index was introduced to quantify the contribution of each failure mode based on the distance from the centroid of the clusters. The design and mechanical properties of the URM walls were then used to predict the hybridity index using a multioutput regression model. The hybridity prediction model determines the contribution of the various failure modes to the ultimate behavior of a damaged URM wall. The proposed framework provides a robust approach to quantifying the relative contribution of each failure mechanism to the overall performance of the URM wall. [ABSTRACT FROM AUTHOR]

Reef rubble from a number of locations in the southwest and central Pacific (Fiji, Kiribati, Solomon Islands) was surveyed for its level of infestation with bioeroding sponges. The assessment was performed by random sampling of reef rubble in shallow water ranging from intertidal to subtidal down to 15 m of water depth. It was found that essentially four styles of bioerosion prevailed: 1) small cavities with roundish cross sections commonly produced by Pione spp. and Cliona cf. macgeachii Holmes; 2) large cavities in the order of cm-size are for example produced by Aka spp., Cliothosa spp., Cliona cf. janitrix Topsent, Cliona cf. ensifera Sollas, and others; 3) multiple etchings which can degrade the interior of coral rubble on a scale of a few cm in diameter are typically produced by both, Cliona orientalis and C. celata species complexes; and 4) large hadromerid sponges are capable of eroding into solid reef rock and produce silt-, sand-, and pebble-sized fragments. Observed was the activity of Spheciospongia solida (Ridley & Dendy) and S. cf. inconstans var. digitata Dendy. These large clionaid sponges are the most efficient eroders on the reef. Species of Pione are abundant at all sites from intertidal to subtidal, and although they are weak bioeroders, they may be the most destructive by number.

Interleukin (IL)-18 is an important effector of innate and adaptive immunity, but its expression must also be tightly regulated because it can potentiate lethal systemic inflammation and death. Healthy and septic human neonates demonstrate elevated serum concentrations of IL-18 compared with adults. Thus, we determined the contribution of IL-18 to lethality and its mechanism in a murine model of neonatal sepsis. We find that IL-18-null neonatal mice are highly protected from polymicrobial sepsis, whereas replenishing IL-18 increased lethality to sepsis or endotoxemia. Increased lethality depended on IL-1 receptor 1 (IL-1R1) signaling but not adaptive immunity. In genome-wide analyses of blood mRNA from septic human neonates, expression of the IL-17 receptor emerged as a critical regulatory node. Indeed, IL-18 administration in sepsis increased IL-17A production by murine intestinal γδT cells as well as Ly6G(+) myeloid cells, and blocking IL-17A reduced IL-18-potentiated mortality to both neonatal sepsis and endotoxemia. We conclude that IL-17A is a previously unrecognized effector of IL-18-mediated injury in neonatal sepsis and that disruption of the deleterious and tissue-destructive IL-18/IL-1/IL-17A axis represents a novel therapeutic approach to improve outcomes for human neonates with sepsis.

The article focuses on documenting and analyzing artifacts from the Savannah River site in Polk County, Tennessee, excavated by F. M. (Ray) Snyder. Topics include the use of different site numbering systems, the types of artifacts recovered such as copper and shell items, and the challenges of tracking provenance at the site level.

Abstract Background Previous studies show a positive association between household wealth and overweight in sub-Saharan African (SSA) countries; however, the manner in which this relationship differs in the presence of educational attainment has not been well-established. This study examined the multiplicative effect modification of educational attainment on the association between middle-income and rich household wealth and overweight status among adult females in 22 SSA countries. We hypothesized that household wealth was associated with a greater likelihood of being overweight among middle income and rich women with lower levels of educational attainment compared to those with higher levels of educational attainment. Methods Demographic and Health Survey (DHS) data from 2006 to 2016 for women aged 18–49 years in SSA countries were used for the study. Overweight was defined as a body mass index (BMI) ≥ 25 kg/m2. Household wealth index tertile was the exposure and educational attainment, the effect modifier. Potential confounders included age, ethnicity, place of residence, and parity. Descriptive analysis was conducted, and separate logistic regression models were fitted for each of the 22 SSA countries to compute measures of effect modification and 95% confidence intervals. Analysis of credibility (AnCred) methods were applied to assess the intrinsic credibility of the study findings and guide statistical inference. Results The prevalence of overweight ranged from 12.6% in Chad to 56.6% in Swaziland. Eighteen of the 22 SSA countries had measures of effect modification below one in at least one wealth tertile. This included eight of the 12 low-income countries and all 10 middle income countries. This implied that the odds of overweight were greater among middle-income and rich women with lower levels of educational attainment than those with higher educational attainment. On the basis of the AnCred analysis, it was found that the majority of the study findings across the region provided some support for the study hypothesis. Conclusions Women in higher wealth strata and with lower levels of educational attainment appear to be more vulnerable to overweight compared to those in the same wealth strata but with higher levels of educational attainment in most low- and middle- income SSA countries.

Regulatory T cells (Tregs) play a central role in counteracting inflammation and autoimmunity. A more complete understanding of cellular heterogeneity and the potential for lineage plasticity in human Treg subsets may identify markers of disease pathogenesis and facilitate the development of optimized cellular therapeutics. To better elucidate human Treg subsets, we conducted direct transcriptional profiling of CD4(+)FOXP3(+)Helios(+) thymic-derived Tregs and CD4(+)FOXP3(+)Helios(-) T cells, followed by comparison with CD4(+)FOXP3(-)Helios(-) T conventional cells. These analyses revealed that the coinhibitory receptor T cell Ig and ITIM domain (TIGIT) was highly expressed on thymic-derived Tregs. TIGIT and the costimulatory factor CD226 bind the common ligand CD155. Thus, we analyzed the cellular distribution and suppressive activity of isolated subsets of CD4(+)CD25(+)CD127(lo/-) T cells expressing CD226 and/or TIGIT. We observed TIGIT is highly expressed and upregulated on Tregs after activation and in vitro expansion, and is associated with lineage stability and suppressive capacity. Conversely, the CD226(+)TIGIT(-) population was associated with reduced Treg purity and suppressive capacity after expansion, along with a marked increase in IL-10 and effector cytokine production. These studies provide additional markers to delineate functionally distinct Treg subsets that may help direct cellular therapies and provide important phenotypic markers for assessing the role of Tregs in health and disease.

A novel laboratory curriculum is presented, developed around some common tasks of a laboratory researcher in chemistry: purification, synthesis, and measurement. The capstone of the sequence is an integrated laboratory, leading to a more independent research experience. Students who have completed this laboratory curriculum appear to perform comparably to previous students who completed a more traditional curriculum, based on their handling of American Chemical Society Exam questions and career placement. Introduction of the new curriculum has coincided with increased numbers of majors as well as increased participation in research, but attributing causation is complicated by the coincidental introduction of a new scholarship program.