Consequential insights for advancing informal STEM learning and outcomes for students from historically marginalized communities.

Consequential STEM experiences in informal settings can address issues of equity by fully engaging historically marginalized high school students in complex socio-scientific issues. However, inclusive and effective programs are in high demand, and there is little research on what specific aspects, context, and timeframes are most important when scaling these experiences. Using a mixed method approach, this study demonstrates that students make significant gains, in the short and long term, through in-person and remote informal programs ranging between 22-h and 320-h. Progress across STEM learning constructs is attributed to authentic research experiences, students' connections to STEM professionals, direct hands-on participation in projects, and group work. Relative to formal education settings, research-based informal STEM programs can be implemented with minimal resources, can maintain effectiveness while scaling, and work towards addressing the societal challenge of improving STEM learning and outcomes for high school students from historically marginalized communities.

Large-scale analysis of Drosophila core promoter function using synthetic promoters.

The core promoter plays a central role in setting metazoan gene expression levels, but how exactly it "computes" expression remains poorly understood. To dissect its function, we carried out a comprehensive structure-function analysis in Drosophila. First, we performed a genome-wide bioinformatic analysis, providing an improved picture of the sequence motifs architecture. We then measured synthetic promoters' activities of ~3,000 mutational variants with and without an external stimulus (hormonal activation), at large scale and with high accuracy using robotics and a dual luciferase reporter assay. We observed a strong impact on activity of the different types of mutations, including knockout of individual sequence motifs and motif combinations, variations of motif strength, nucleosome positioning, and flanking sequences. A linear combination of the individual motif features largely accounts for the combinatorial effects on core promoter activity. These findings shed new light on the quantitative assessment of gene expression in metazoans.

Transcription Factor Binding Affinities and DNA Shape Readout.

An essential event in gene regulation is the binding of a transcription factor (TF) to its target DNA. Models considering the interactions between the TF and the DNA geometry proved to be successful approaches to describe this binding event, while conserving data interpretability. However, a direct characterization of the DNA shape contribution to binding is still missing due to the lack of accurate and large-scale binding affinity data. Here, we use a binding assay we recently established to measure with high sensitivity the binding specificities of 13 Drosophila TFs, including dinucleotide dependencies to capture non-independent amino acid-base interactions. Correlating the binding affinities with all DNA shape features, we find that shape readout is widely used by these factors. A shape readout/TF-DNA complex structure analysis validates our approach while providing biological insights such as positively charged or highly polar amino acids often contact nucleotides that exhibit strong shape readout.

Sensitive Automated Measurement of Histone-DNA Affinities in Nucleosomes.

The DNA of eukaryotes is wrapped around histone octamers to form nucleosomes. Although it is well established that the DNA sequence significantly influences nucleosome formation, its precise contribution has remained controversial, partially owing to the lack of quantitative affinity data. Here, we present a method to measure DNA-histone binding free energies at medium throughput and with high sensitivity. Competitive nucleosome formation is achieved through automation, and a modified epifluorescence microscope is used to rapidly and accurately measure the fractions of bound/unbound DNA based on fluorescence anisotropy. The procedure allows us to obtain full titration curves with high reproducibility. We applied this technique to measure the histone-DNA affinities for 47 DNA sequences and analyzed how the affinities correlate with relevant DNA sequence features. We found that the GC content has a significant impact on nucleosome-forming preferences, but 10 bp dinucleotide periodicities and the presence of poly(dA:dT) stretches do not.

Definition of efficiency in vacuum therapy--a randomised controlled trial comparing with V.A.C. Therapy.

Redon drains are still used to suction wounds for vacuum sealing. Vacuum-assisted closure (V.A.C.((R)); Kinetic Concepts Inc, San Antonio, TX) is a computer-controlled therapy system for delivering topical negative pressure therapy. The efficiency of V.A.C. in the treatment of pressure ulcers was prospectively studied in a randomised controlled trial in which patients with pressure ulcers were randomly assigned to negative pressure wound therapy (NPWT) using either V.A.C. or Redon bottles. The target parameters were absolute and relative proportion of wound area consists of granulation tissue, fibrin and necrosis. Other outcome measures were the number of dressing changes and time invested using each system. The study was terminated after a post hoc analysis after inclusion of ten patients because of the significantly better results when using V.A.C., and the substantially larger care effort needed in the Redon group compared with the V.A.C. group. An increase in surface granulation tissue of 54% was observed in the V.A.C. group, and a reduction in the Redon group (P = 0.001). The Redon group showed an increase in fibrin tissue at the wound base of 21.8%, whereas in the V.A.C group, a 27% reduction was observed (P = 0.035). Necrosis was reduced in the V.A.C. group, but this difference did not reach significance. Redon bottles are not a good alternative for V.A.C. therapy for delivering NPWT.

The effect of structured strength and balance training on cognitive function in frail, cognitive impaired elderly long-term care residents.

BACKGROUND AND AIMS: The aim of the study was to assess the effect of structured strength and balance training on cognitive function in frail, geriatric, long-term care facility residents, aged 75 years or older, and additionally to evaluate the influence of training on various functional, physical and psychological parameters. METHODS: Participants were randomly assigned to a training group or a control group. Physical training was performed three times a week for ten weeks in the training group. Muscle function was assessed by manual examination on a scale of 0-5. Cognitive function was tested with the Mini Mental State Examination (MMSE). In addition, scores for activities of daily living, mobility and depression were assessed. RESULTS: 30 subjects with a mean age of 86.8 years completed the study. After 10 weeks of intervention in the training group, muscle strength increased from a mean of 3.75 to 4.44 points (p<0.001) and the mean MMSE score increased from 20.9 to 23.9 points (p=0.023). In the training group, the change in the MMSE score correlated significantly with change in muscle function, with a Pearson correlation coefficient of 0.750 (p=0.002). An increase in mean BMI from 23.8 to 25.0 kg/m2 (p=0.013) was also found in the training group, but no significant changes in scores for activities of daily living, mobility or depression. Compared with the control group, the change in the mean scores over the ten-week training period was significantly higher for the trained group with regard to muscle scores, BMI and lean body mass, but not for MMSE scores. CONCLUSIONS: Our findings reinforce the recommendation that structured strength and balance training should be implemented in long-term care facilities. Besides the well-known benefits of physical training, our findings showed that an improvement in cognitive function may also be possible.