Easy Microscale Electrolysis of Water

The following is a quick, easy, visible demonstration which makes an eye-catching introduction to electrochemistry and electrolysis

Counting Centralizers in Finite Groups

We discuss various results on the number of commuting pairs and the sizes of the centralizers of a group

Framing Novice Teacher Persistence: A Collective Case Study of Early-Career African-American Teachers in Urban Public Schools

Efforts to recruit high-quality minority teachers have proven successful over the past two decades, particularly for low-income, high-minority, and urban schools. Unfortunately, increases in minority teacher hiring have been undermined by the high turnover rates of minority teachers and novice teachers -- e.g. teachers who have less than five years of professional teaching experience. Teachers who embody both of these characteristics, novice minority teachers, are doubly disadvantaged because they experience higher turnover rates than their colleagues. As a result, low-income, high-minority, and urban schools continue to struggle to maintain teacher staffing levels for the student populations with the greatest need for quality and consistency. The purpose of the study was to explore why novice African-American teachers choose to remain in the profession after their first three years of teaching in urban school settings. Through the lens of social cognitive career theory (Lent, Brown & Hackett, 1994, 2000, 2002), the study explored novice African-American teachers’ personal characteristics and background experiences which framed their pursuit of a teaching career, identified the contextual challenges and supports which had the greatest impact on their teaching self-efficacy and outcome expectations, and examined how these teachers mitigated apparent and perceived challenges to career persistence. A qualitative collective case study design (Stake, 2005; 2006) was used to gain a deeper understanding of how novice African-American teachers’ personal characteristics, background experiences, and contextual factors proximal to teaching shaped their career self-efficacy, outcome expectations, and persistence in urban schools. This study adds the novice African-American teacher voice to existing research on novice urban teacher retention and provide a better understanding of their unique needs. The findings of this study can be used to develop targeted teacher training, recruitment and induction initiatives designed to increase the number of African-American teachers who eventually enter and sustain the urban teaching workforce

Need for timely paediatric HIV treatment within primary health care in rural South Africa

<p>Background: In areas where adult HIV prevalence has reached hyperendemic levels, many infants remain at risk of acquiring HIV infection. Timely access to care and treatment for HIV-infected infants and young children remains an important challenge. We explore the extent to which public sector roll-out has met the estimated need for paediatric treatment in a rural South African setting.</p> <p>Methods: Local facility and population-based data were used to compare the number of HIV infected children accessing HAART before 2008, with estimates of those in need of treatment from a deterministic modeling approach. The impact of programmatic improvements on estimated numbers of children in need of treatment was assessed in sensitivity analyses.</p> <p>Findings: In the primary health care programme of HIV treatment 346 children <16 years of age initiated HAART by 2008; 245(70.8%) were aged 10 years or younger, and only 2(<1%) under one year of age. Deterministic modeling predicted 2,561 HIV infected children aged 10 or younger to be alive within the area, of whom at least 521(20.3%) would have required immediate treatment. Were extended PMTCT uptake to reach 100% coverage, the annual number of infected infants could be reduced by 49.2%.</p> <p>Conclusion: Despite progress in delivering decentralized HIV services to a rural sub-district in South Africa, substantial unmet need for treatment remains. In a local setting, very few children were initiated on treatment under 1 year of age and steps have now been taken to successfully improve early diagnosis and referral of infected infants.</p&gt

Effects of Ion Atomic Number on Single-Event Gate Rupture (SEGR) Susceptibility of Power MOSFETs

The relative importance of heavy-ion interaction with the oxide, charge ionized in the epilayer, and charge ionized in the drain substrate, on the bias for SEGR failure in vertical power MOSFETs is experimentally investigated. The results indicate that both the charge ionized in the epilayer and the ion atomic number are important parameters of SEGR failure. Implications on SEGR hardness assurance are discussed

Sotatercept (ACE-011) for the treatment of chemotherapy-induced anemia in patients with metastatic breast cancer or advanced or metastatic solid tumors treated with platinum-based chemotherapeutic regimens: results from two phase 2 studies

PURPOSE: Sotatercept may represent a novel approach to the treatment of chemotherapy-induced anemia (CIA). We report the results from two phase 2 randomized studies examining the use of sotatercept for the treatment of CIA in patients with metastatic cancer. METHODS: In study A011-08, patients with metastatic breast cancer were randomized to 2:2:2:1 to receive sotatercept 0.1, 0.3, or 0.5 mg/kg, or placebo, respectively, every 28 days. In study ACE-011-NSCL-001, patients with solid tumors treated with platinum-based chemotherapy received sotatercept 15 or 30 mg every 42 days. The primary endpoint for both studies was hematopoietic response, defined as a hemoglobin (Hb) increase of \u3e/=1 g/dL from baseline. RESULTS: Both studies were terminated early due to slow patient accrual. Among patients treated with sotatercept in the A011-08 and ACE-011-NSCL-001 studies, more patients achieved a mean Hb increase of \u3e/=1 g/dL in the combined sotatercept 0.3 mg/kg and 15 mg (66.7 %) group and sotatercept 0.5 mg/kg and 30 mg (38.9 %) group versus the sotatercept 0.1 mg/kg (0 %) group. No patients achieved a mean Hb increase of \u3e/=1 g/dL in the placebo group. The incidence of treatment-related adverse events (AEs) was low in both studies, and treatment discontinuations due to AEs were uncommon. CONCLUSIONS: Although both studies were terminated early, these results indicate that sotatercept is active and has an acceptable safety profile in the treatment of CIA

Localisation, personalisation and delivery of best practice guidelines on an integrated care and cure cloud architecture : the C3-cloud approach to managing multimorbidity

Background: C3-Cloud is an integrated care ICT infrastructure offering seamless patient-centered approach to managing multimorbidity, deployed in three European pilot sites. Challenge: The digital delivery of best practice guidelines unified for multimorbidity, customized to local practice, offering the capability to improve patient personalization and benefit. Method: C3-Cloud has adopted a co-production approach to developing unified multimorbidity guidelines, by collating and reconciling best practice guidelines for each condition. Clinical and technical teams at pilot sites and the C3-Cloud consortium worked in tandem to create the specification and technical implementation. Results: C3-Cloud offers CDSS for diabetes, renal failure, depression and congenital heart failure, with over 300 rules and checks that deliver four best practice guidelines in parallel, customized for each pilot site. Conclusions: The process provided a traceable, maintainable and audited digitally delivered collated and reconciled guidelines

Accelerating metabolic models evaluation with statistical metamodels: application to Salmonella infection models

Mathematical and numerical models are increasingly used in microbial ecology to model the fate of microbial communities in their ecosystem. These models allow to connect in a mechanistic framework species-level informations, such as the microbial genomes, with macro-scale features, such as species spatial distributions or metabolite gradients. Numerous models are built upon species-level metabolic models that predict the metabolic behaviour of a microbe by solving an optimization problem knowing its genome and its nutritional environment. However, screening the community dynamics with these metabolic models implies to solve such an optimization problem by species at each time step, leading to a significant computational load further increased by several orders of magnitude when spatial dimensions are added. In this paper, we propose a statistical framework based on Reproducing Kernel Hilbert Space (RKHS) metamodels that are used to provide fast approximations of the original metabolic model. The metamodel can replace the optimization step in the system dynamics, providing comparable outputs at a much lower computational cost. We will first build a system dynamics model of a simplified gut microbiota composed of a unique commensal bacterial strain in interaction with the host and challenged by a Salmonella infection. Then, the machine learning method will be introduced, and particularly the ANOVA-RKHS that will be exploited to achieve variable selection and model parsimony. A training dataset will be constructed with the original system dynamics model and hyper-parameters will be carefully chosen to provide fast and accurate approximations of the original model. Finally, the accuracy of the trained metamodels will be assessed, in particular by comparing the system dynamics outputs when the original model is replaced by its metamodel. The metamodel allows an overall relative error of 4.71% but reducing the computational load by a speed-up factor higher than 45, while correctly reproducing the complex behaviour occurring during Salmonella infection. These results provide a proof-of-concept of the potentiality of machine learning methods to give fast approximations of metabolic model outputs and pave the way towards PDE-based spatio-temporal models of microbial communities including microbial metabolism and host-microbiota-pathogen interactions