Integration, not Gentrification: Using Participatory Action Research to Foster Democratic Leadership in an Urban PTA

This study explores the relationship of a new Parent Teacher Association (PTA) to a historically low-income public school in a gentrifying neighborhood. The PTA was formed by a group of white middle class parents who did not reflect the broader school population. To serve diverse communities, school leaders need to organize families to participate in the school democratically. Utilizing Participatory Action Research (PAR), this study demonstrates that there are no shortcuts to building more democratic parental participation in diverse urban schools: communities need to engage in collaborative inquiry to dismantle barriers to involvement, strengthen the connection between home and school, and recruit and develop more representative leadership

Proteome analysis of serovars Typhimurium and Pullorum of Salmonella enterica subspecies I

BACKGROUND: Salmonella enterica subspecies I includes several closely related serovars which differ in host ranges and ability to cause disease. The basis for the diversity in host range and pathogenic potential of the serovars is not well understood, and it is not known how host-restricted variants appeared and what factors were lost or acquired during adaptations to a specific environment. Differences apparent from the genomic data do not necessarily correspond to functional proteins and more importantly differential regulation of otherwise identical gene content may play a role in the diverse phenotypes of the serovars of Salmonella. RESULTS: In this study a comparative analysis of the cytosolic proteins of serovars Typhimurium and Pullorum was performed using two-dimensional gel electrophoresis and the proteins of interest were identified using mass spectrometry. An annotated reference map was created for serovar Typhimurium containing 233 entries, which included many metabolic enzymes, ribosomal proteins, chaperones and many other proteins characteristic for the growing cell. The comparative analysis of the two serovars revealed a high degree of variation amongst isolates obtained from different sources and, in some cases, the variation was greater between isolates of the same serovar than between isolates with different sero-specificity. However, several serovar-specific proteins, including intermediates in sulphate utilisation and cysteine synthesis, were also found despite the fact that the genes encoding those proteins are present in the genomes of both serovars. CONCLUSION: Current microbial proteomics are generally based on the use of a single reference or type strain of a species. This study has shown the importance of incorporating a large number of strains of a species, as the diversity of the proteome in the microbial population appears to be significantly greater than expected. The characterisation of a diverse selection of strains revealed parts of the proteome of S. enterica that alter their expression while others remain stable and allowed for the identification of serovar-specific factors that have so far remained undetected by other methods

High voltage measurements on a prototype PFN for the LHC injection kickers

Two LHC injection kicker magnet systems must produce a kick of 1.3 T.m each with a flattop duration of 4.25 mu s or 6.5 mu s, a rise time of 900 ns, and a fall time of 3 mu s. The ripple in the field must be less than +or-0.5The electrical circuit of the complete system has been simulated with PSpice. The model includes a 66 kV resonant charging power supply (RCPS), a 5 Omega pulse forming network (PFN), a terminated 5 Omega kicker magnet, and all known parasitic quantities. Component selection for the PEN was made on the basis of models in which a theoretical field ripple of less than +or-0.1as attained. A prototype 66 kV RCPS was built at TRIUMF and shipped to CERN. A prototype 5 Omega system including a PFN, thyratron switches, and terminating resistors, was built at CERN. The system (without a kicker magnet) was assembled as designed without trimming of any PFN component values. The PFN was charged to 60 kV via the RCPS operating at 0.1 Hz. The thyratron timing was adjusted to provide a 30 kV, 5.5 mu s duration pulse on a 5 Omega terminating resistor. Measurement data is presented for the prototype PFN, connected to resistive terminators. A procedure has been developed for compensating the probe and oscilloscope amplifier calibration errors. The top of the 30 kV pulse is flat to +or-0.3after an initial oscillation of 600 ns total duration. The post-pulse period is flat to within +or-0.1after approximately 600 ns from the bottom of the falling edge of the pulse. A calculation was performed in which a measured 27.5 kV pulse with a 5.5 mu s flattop was fed into a PSpice model of a kicker magnet with a 690 ns delay length. The resultant predicted kick rise time, from 0.2to 99.8, is 834 ns and the fall time 2.94 mu s, for a field pulse with a flattop of 4.69 mu s and a ripple of less than +or-0.2(12 refs)

Assessment of aortic regurgitation by transesophageal color Doppler imaging of the vena contracta: validation against an intraoperative aortic flow probe

AbstractOBJECTIVESThis study was performed to validate the accuracy of color flow vena contracta (VC) measurements of aortic regurgitation (AR) severity by comparing them to simultaneous intraoperative flow probe measurements of regurgitant fraction (RgF) and regurgitant volume (RgV).BACKGROUNDColor Doppler imaging of the vena contracta has emerged as a simple and reliable measure of the severity of valvular regurgitation. This study evaluated the accuracy of VC imaging of AR by transesophageal echocardiography (TEE).METHODSA transit-time flow probe was placed on the ascending aorta during cardiac surgery in 24 patients with AR. The flow probe was used to measure RgF and RgV simultaneously during VC imaging by TEE. Flow probe and VC imaging were interpreted separately and in blinded fashion.RESULTSA good correlation was found between VC width and RgF (r = 0.85) and RgV (r = 0.79). All six patients with VC width >6 mm had a RgF >0.50. All 18 patients with VC width <5 mm had a RgF <0.50. Vena contracta area also correlated well with both RgF (r = 0.81) and RgV (r = 0.84). All six patients with VC area >7.5 mm2had a RgF >0.50, and all 18 patients with a VC area <7.5 mm2had a RgF <0.50. In a subset of nine patients who underwent afterload manipulation to increase diastolic blood pressure, RgV increased significantly (34 ± 26 ml to 41 ± 27 ml, p = 0.042) while VC width remained unchanged (5.4 ± 2.8 mm to 5.4 ± 2.8 mm, p = 0.41).CONCLUSIONSVena contracta imaging by TEE color flow mapping is an accurate marker of AR severity. Vena contracta width and VC area correlate well with RgF and RgV obtained by intraoperative flow probe. Vena contracta width appears to be less afterload-dependent than RgV

Learning about research by doing research: developing student researchers

In this article senior lecturers and second year students from the BA (Hons) Primary Education programme at Bishop Grosseteste University, who were involved in an educational research project, reflect on the importance of teacher led research and the impact on students of leading their own research projects. Teachers’ involvement with knowledge creation is widely recognised as an effective form of professional development (Hopkins, 2014; Taber, 2013). There has also been an increasingly prevalent binary view of Initial Teacher Education in which the real practical learning goes on in school placements whilst more theoretical learning goes on in universities (Czerniawski, 2018). However, student teacher research involving children should be seen as a consolidation of theory and practice. It is therefore essential that student teachers learn how to carry out research involving children, understand the ethical implications of this and recognise the value of reflecting on the effectiveness of pedagogical approaches. However, undertaking this kind of practitioner research can be daunting. Over the period of six weeks, the students were coached in research methods, data collection, analysis of data and drawing conclusions. Children from partnership schools visited the university to take part in the research tasks. This gave the students a valuable insight to key aspects of teaching and learning such as the children’s reading preferences, the use of digital resources to teach science and using story to support mathematical understanding. Students’ findings were presented in the form of research posters. Students found the project an interesting way to develop their understanding of research and reflected positively about what they had learnt about research methods

A neuronal network of mitochondrial dynamics regulates metastasis.

The role of mitochondria in cancer is controversial. Using a genome-wide shRNA screen, we now show that tumours reprogram a network of mitochondrial dynamics operative in neurons, including syntaphilin (SNPH), kinesin KIF5B and GTPase Miro1/2 to localize mitochondria to the cortical cytoskeleton and power the membrane machinery of cell movements. When expressed in tumours, SNPH inhibits the speed and distance travelled by individual mitochondria, suppresses organelle dynamics, and blocks chemotaxis and metastasis, in vivo. Tumour progression in humans is associated with downregulation or loss of SNPH, which correlates with shortened patient survival, increased mitochondrial trafficking to the cortical cytoskeleton, greater membrane dynamics and heightened cell invasion. Therefore, a SNPH network regulates metastatic competence and may provide a therapeutic target in cancer

Polarizing Grids, Their Assemblies and Beams of Radiation

This article gives an analysis of the behavior of polarizing grids and reflecting polarizers by solving Maxwell's equations, for arbitrary angles of incidence and grid rotation, for cases where the excitation is provided by an incident plane wave or a beam of radiation. The scattering and impedance matrix representations are derived and used to solve more complicated configurations of grid assemblies. The results are also compared with data obtained in the calibration of reflecting polarizers at the Owens Valley Radio Observatory (OVRO). From this analysis, we propose a method for choosing the optimum grid parameters (wire radius and spacing). We also provide a study of the effects of two types of errors (in wire separation and radius size) that can be introduced in the fabrication of a grid.Comment: 35 pages, 6 figure

Harvard Personal Genome Project: lessons from participatory public research

Background: Since its initiation in 2005, the Harvard Personal Genome Project has enrolled thousands of volunteers interested in publicly sharing their genome, health and trait data. Because these data are highly identifiable, we use an ‘open consent’ framework that purposefully excludes promises about privacy and requires participants to demonstrate comprehension prior to enrollment. Discussion Our model of non-anonymous, public genomes has led us to a highly participatory model of researcher-participant communication and interaction. The participants, who are highly committed volunteers, self-pursue and donate research-relevant datasets, and are actively engaged in conversations with both our staff and other Personal Genome Project participants. We have quantitatively assessed these communications and donations, and report our experiences with returning research-grade whole genome data to participants. We also observe some of the community growth and discussion that has occurred related to our project. Summary We find that public non-anonymous data is valuable and leads to a participatory research model, which we encourage others to consider. The implementation of this model is greatly facilitated by web-based tools and methods and participant education. Project results are long-term proactive participant involvement and the growth of a community that benefits both researchers and participants