Problemas de estabilidade de desempenho dos professores não são novos: Limitações e possibilidades

Morgan, Hodge, Trepinski, and Anderson (2014) have written an article that continues to confirm what we have known for some time—teacher effects on student achievement have limited stability. In this commentary, we address the other potential contributions this work can make to inform practice, policy, and research. While illustrating Morgan et al.’s inattention to history, we take the opportunity to reframe their findings. Considering the authors’ work in the context of past and current research, we illustrate that this collective set of stable evidence should convince policymakers that it is not reasonable to assume that teachers and teaching is stable across time. Beyond this important opportunity to influence policy, we believe these findings underscore the need to build upon and expand the dependent measures we use to define and understand good teaching. After all, as we have noted (Lavigne Good, 2014; in press) good teaching involves much more than increasing students’ scores on standardized achievement tests. Morgan, Hodge, Trepinski, y Anderson (2014) han escrito un artículo que sigue confirmando lo que hemos sabido sobre la estabilidad limitada que los efectos docentes tienen en los logros de los estudiantes. En este comentario, queremos señala otras contribuciones potenciales de este trabajo que podrían informar  la práctica, política e investigación educativa. Mientras que señalamos que Morgan y colegas no prestaron suficiente atención a la historia, tenemos la oportunidad de replantear sus hallazgos. Teniendo en cuenta el trabajo de los autores en el contexto de investigaciones pasadas y actuales, proponemos que este conjunto colectivo de pruebas estable debe convencer a los políticos de que no es razonable suponer que los docentes y la enseñanza es estable a través del tiempo. Más allá de esta importante oportunidad de influir en la política, creemos que estos resultados ponen de relieve la necesidad de aprovechar y ampliar las medidas dependientes que usamos para definir y entender la buena enseñanza. Después de todo, como hemos señalado (Lavigne Good 2014; en prensa) buena enseñanza implica mucho más que el aumento de calificaciones de los estudiantes en pruebas estandarizadasMorgan, Hodge, Trepinski, e Anderson (2014) escreveram um artigo que confirma o que já sabemos sobre a estabilidade limitada dos efeitos que os professores têm sobre as avanços dos estudantes. Nese comentário, observamos outras contribuições potenciais do presente trabalho, que poderia informar a prática, política e pesquisa educacional. Enquanto notamos que Morgan e seus colegas não prestaram atenção suficiente para a história, temos a oportunidade de repensar as suas conclusões. Considerando-se o trabalho dos autores no contexto do passado e atual da pesquisa, propomos que este conjunto coletivo de provas estáveis deveria convencer os políticos de que não é razoável supor que os professores e o ensino é estável ao longo do tempo. Além deste importante oportunidade de influenciar a política, acreditamos que estes resultados destacam a necessidade de construir e expandir as medidas que usamos para definir e compreender o que é o bom ensino. Afinal, como já observamos (Lavigne Good 2014; no prelo) bom ensino envolve muito mais do que o aumento na pontuação em testes padronizado

Issues of teacher performance stability are not new: Limitations and possibilities

Morgan, Hodge, Trepinski, and Anderson (2014) have written an article that continues to confirm what we have known for some time—teacher effects on student achievement have limited stability. In this commentary, we address the other potential contributions this work can make to inform practice, policy, and research. While illustrating Morgan et al.’s inattention to history, we take the opportunity to reframe their findings. Considering the authors’ work in the context of past and current research, we illustrate that this collective set of stable evidence should convince policymakers that it is not reasonable to assume that teachers and teaching is stable across time. Beyond this important opportunity to influence policy, we believe these findings underscore the need to build upon and expand the dependent measures we use to define and understand good teaching. After all, as we have noted (Lavigne & Good, 2014; in press) good teaching involves much more than increasing students’ scores on standardized achievement tests

Using Dyadic Observation to Explore Equitable Learning Opportunities in Classroom Instruction

Because of poverty, many children do not receive adequate prenatal care, nutrition, or early childhood education. These inequities combine to ensure that many students enter school with considerably less academic content knowledge and skills for learning than their peers. Teachers and schools did not create these gaps, but they must address them. The impact of schools in reducing gaps has been explored for decades only to yield inconsistent findings. One possible reason for these contradictory results is because these studies ignore classroom process. We argue for the inclusion of process in research on opportunity and achievement gaps to better articulate if schools provide inequitable learning opportunities. Further, we argue for dyadic (teacher to individual student) measurement of classroom process because commonly-used observation instruments only measure teachers’ interactions with the whole class. These instruments obscure differential teacher treatment that may exist in some classrooms. To improve policy and practice, we call for supplementing extant measures of teachers’ whole-class interactions (process) and student outcome (product) measures with those that measure dyadic interactions to learn how opportunities to learn in classrooms and schools are distributed among students to reduce, sustain, or enhance learning gaps

Experimental phage therapy of burn wound infection : difficult first steps

Antibiotic resistance has become a major public health problem and the antibiotics pipeline is running dry. Bacteriophages (phages) may offer an ‘innovative’ means of infection treatment, which can be combined or alternated with antibiotic therapy and may enhance our abilities to treat bacterial infections successfully. Today, in the Queen Astrid Military Hospital, phage therapy is increasingly considered as part of a salvage therapy for patients in therapeutic dead end, particularly those with multidrug resistant infections. We describe the application of a well-defined and quality controlled phage cocktail, active against Pseudomonas aeruginosa and Staphylococcus aureus, on colonized burn wounds within a modest clinical trial (nine patients, 10 applications), which was approved by a leading Belgian Medical Ethical Committee. No adverse events, clinical abnormalities or changes in laboratory test results that could be related to the application of phages were observed. Unfortunately, this very prudent ‘clinical trial’ did not allow for an adequate evaluation of the efficacy of the phage cocktail. Nevertheless, this first ‘baby step’ revealed several pitfalls and lessons for future experimental phage therapy and helped overcome the psychological hurdles that existed to the use of viruses in the treatment of patients in our burn unit

Design of novel γ’ bondcoats and interdiffusion with Re-rich superalloys

Increasing the life of thermal barrier coating (TBC) systems critically relies on maintaining good adhesion between the bondcoat, the thermally grown oxide (TGO) and the topcoat. A common cause of failure, rumpling occurs as stress generated by oxide growth and thermal cycling results in creep of the mechanically weak bondcoat – this currently limits the life of EB-PVD TBCs with β coatings used in aircraft turbine blades and vanes. γ’ coatings are known to present a better creep strength than β coatings and thereby markedly reduce rumpling, while still offering adequate oxidation resistance. The higher solubility of reactive elements (RE) in γ’ also provides more flexibility in optimizing RE additions, as it limits the risk of overdoping; this can be used to further improve TGO adhesion. Furthermore, γ’ compositions can, by essence, be adjusted to reduce the chemical potential mismatch with the substrate; this in turn will help curb the development of secondary reaction zones, which have become an issue when β coatings are used on Re-containing superalloys. The poster will present recent efforts made at ONERA in the development of new γ’ compositions for Re-rich substrates. Our current design strategy focuses on limiting substrate-coating interdiffusion and the associated loss of load-bearing section in the alloy. As mechanical properties improve and the bondcoat Al content is reduced, however, the bondcoat ability to maintain exclusive Al2O3 formation throughout extended cycling becomes critical to the system durability. Coating compositions are thus adjusted to a given alloy following the “equilibrium coating” concept, and then slightly modified to help maintain an appropriate composition relative to oxidation resistance. Compositions are assessed through the study of interdiffusion profiles obtained from both experiments and numerical simulations via a finite-difference method

Systematic analysis of the kalimantacin assembly line NRPS module using an adapted targeted mutagenesis approach

Kalimantacin is an antimicrobial compound with strong antistaphylococcal activity that is produced by a hybrid trans-acyltransferase polyketide synthase/nonribosomal peptide synthetase system in Pseudomonas fluorescens BCCM_ID9359. We here present a systematic analysis of the substrate specificity of the glycine-incorporating adenylation domain from the kalimantacin biosynthetic assembly line by a targeted mutagenesis approach. The specificity-conferring code was adapted for use in Pseudomonas and mutated adenylation domain active site sequences were introduced in the kalimantacin gene cluster, using a newly adapted ligation independent cloning method. Antimicrobial activity screens and LC-MS analyses revealed that the production of the kalimantacin analogues in the mutated strains was abolished. These results support the idea that further insight in the specificity of downstream domains in nonribosomal peptide synthetases and polyketide synthases is required to efficiently engineer these strains in vivo

Multi-compartment poroelastic models of perfused biological soft tissues: implementation in FEniCSx

Soft biological tissues demonstrate strong time-dependent and strain-rate mechanical behavior, arising from their intrinsic visco-elasticity and fluid-solid interactions (especially at sufficiently large time scales). The time-dependent mechanical properties of soft tissues influence their physiological functions and are linked to several pathological processes. Poro-elastic modeling represents a promising approach because it allows the integration of multiscale/multiphysics data to probe biologically relevant phenomena at a smaller scale and embeds the relevant mechanisms at the larger scale. The implementation of multi-phasic flow poro-elastic models however is a complex undertaking, requiring extensive knowledge. The open-source software FEniCSx Project provides a novel tool for the automated solution of partial differential equations by the finite element method. This paper aims to provide the required tools to model the mixed formulation of poro-elasticity, from the theory to the implementation, within FEniCSx. Several benchmark cases are studied. A column under confined compression conditions is compared to the Terzaghi analytical solution, using the L2-norm. An implementation of poro-hyper-elasticity is proposed. A bi-compartment column is compared to previously published results (Cast3m implementation). For all cases, accurate results are obtained in terms of a normalized Root Mean Square Error (RMSE). Furthermore, the FEniCSx computation is found three times faster than the legacy FEniCS one. The benefits of parallel computation are also highlighted.Comment: https://github.com/Th0masLavigne/Dolfinx_Porous_Media.gi

Autonomic pain responses during sleep: a study of heart rate variability

The autonomic nervous system (ANS) reacts to nociceptive stimulation during sleep, but whether this reaction is contingent to cortical arousal, and whether one of the autonomic arms (sympathetic/parasympathetic) predominates over the other remains unknown. We assessed ANS reactivity to nociceptive stimulation during all sleep stages through heart rate variability, and correlated the results with the presence of cortical arousal measured in concomitant 32-channel EEG. Fourteen healthy volunteers underwent whole-night polysomnography during which nociceptive laser stimuli were applied over the hand. RR intervals (RR) and spectral analysis by wavelet transform were performed to assess parasympathetic (HF(WV)) and sympathetic (LF(WV) and LF(WV)/HF(WV) ratio) reactivity. During all sleep stages, RR significantly decreased in reaction to nociceptive stimulations, reaching a level similar to that of wakefulness, at the 3rd beat post-stimulus and returning to baseline after seven beats. This RR decrease was associated with an increase in sympathetic LF(WV) and LF(WV)/HF(WV) ratio without any parasympathetic HF(WV) change. Albeit RR decrease existed even in the absence of arousals, it was significantly higher when an arousal followed the noxious stimulus. These results suggest that the sympathetic-dependent cardiac activation induced by nociceptive stimuli is modulated by a sleep dependent phenomenon related to cortical activation and not by sleep itself, since it reaches a same intensity whatever the state of vigilance

Stroke saturation on a MEMS deformable mirror for woofer-tweeter adaptive optics

High-contrast imaging of extrasolar planet candidates around a main-sequence star has recently been realized from the ground using current adaptive optics (AO) systems. Advancing such observations will be a task for the Gemini Planet Imager, an upcoming "extreme" AO instrument. High-order "tweeter" and low-order "woofer" deformable mirrors (DMs) will supply a >90%-Strehl correction, a specialized coronagraph will suppress the stellar flux, and any planets can then be imaged in the "dark hole" region. Residual wavefront error scatters light into the DM-controlled dark hole, making planets difficult to image above the noise. It is crucial in this regard that the high-density tweeter, a micro-electrical mechanical systems (MEMS) DM, have sufficient stroke to deform to the shapes required by atmospheric turbulence. Laboratory experiments were conducted to determine the rate and circumstance of saturation, i.e. stroke insufficiency. A 1024-actuator 1.5-um-stroke MEMS device was empirically tested with software Kolmogorov-turbulence screens of r_0=10-15cm. The MEMS when solitary suffered saturation ~4% of the time. Simulating a woofer DM with ~5-10 actuators across a 5-m primary mitigated MEMS saturation occurrence to a fraction of a percent. While no adjacent actuators were saturated at opposing positions, mid-to-high-spatial-frequency stroke did saturate more frequently than expected, implying that correlations through the influence functions are important. Analytical models underpredict the stroke requirements, so empirical studies are important.Comment: 16 pages, 10 figure