Culture and Curriculum Collide: the Case of Spoken Word in the Classroom

One of the greatest obstacles that educators must face is keeping all students engaged in their learning. Today schools are searching for ways to make their classrooms not only multicultural in order to appeal to all students, but they are also searching for new innovative ways to engage students. Recently schools have begun to employ popular culture in the classroom to engage students. I propose that schools use spoken word poetry in the classroom to create a multicultural space that is also interesting for all students

Propagation d'ondes élastiques dans des multicouches autosimilaires : application aux composites stratifiés renforcés de fibres de carbone

Les matériaux composites renforcés de fibres de carbone sont largement utilisés dans l'industrie. L'association de leurs propriétés de drapage avec le concept d'autosimilarité permet de créer des matériaux innovants. Nous étudions numériquement et expérimentalement la propagation des ondes élastiques dans ces milieux. L'ensemble de Cantor et la suite de Fibonacci génèrent des structures autosimilaires. Les matériaux composites stratifiés renforcés de fibres de carbone sont constitués de plis orthotropes. Nous fabriquons des empilements basés sur l'ensemble de Cantor et la suite de Fibonacci : les processus autosimilaires sont appliqués sur l'arrangement et l'orientation des plis. Un code de calcul unidimensionnel permet de comparer structures périodiques, désordonnées et autosimilaires. Nous montrons que l'autosimilarité des arrangements apparaît dans la transmission acoustique et que les matériaux autosimilaires possèdent à la fois les propriétés de milieux périodiques et aléatoires : bandes interdites et états localisés. L'étude expérimentale ultrasonore d'échantillons composites carbone/PEEK ordonnés et autosimilaires et l'algorithme de la matrice de raideur modélisant la propagation des ondes dans ces matériaux, montrent que les empilements autosimilaires créent des irrégularités déterministes favorables à la réduction de la transmission acoustique et à l'augmentation de l'atténuation. La dimension d'homothétie permet alors d'adapter le rapport taille des hétérogénéités sur longueur d'onde pour optimiser les arrangements.Fiber reinforced composites are more and more used in industry. The association of their draping properties with self-similarity allows to create innovative materials. Elastic wave propagation in such media is numerically and experimentally studied. The Cantor's set and the Fibonacci sequence generate self-similar structures. Moreover, stratified fiber reinforced composites are constituted by a draping of orthotropic plies. Multilayered Cantor and Fibonacci stacks are manufactured. Self-similarity is applied on geometry and on plies orientation. Periodic, disordered and self-similar structures are compared thanks to a unidirectional numerical model based on a transfer matrix formalism. It shows that stacks self-similarity influences the acoustic transmission properties. Self-similar stacks transmission coefficient presents a self-similar shape and behavior. It is demonstrated that self-similar structures possess periodic and disordered media properties. They combine band-gaps and localization phenomena. Ordered and self-similar samples are then experimentally compared through ultrasonic measures. Experimental transmission coefficients, phase velocities end attenuations indicate that the more disorder there is, the lower the global transmission is and the higher the intrinsic attenuation is. Finally, elastic waves propagation is computed thanks to the stiffness matrix algorithm. It is shown that self-similar structures create deterministic irregularities enhancing the drop of the acoustic transmission and the increase of attenuation. The homothetic dimension allows to adapt the ratio between heterogeneities and wavelength to optimize the self-similar stacks

Staphylococcus aureus in the oral cavity: a three-year retrospective analysis of clinical laboratory data

OBJECTIVE: A retrospective analysis of laboratory data to investigate the isolation of Staphylococcus aureus from the oral cavity and facial area in specimens submitted to a regional diagnostic oral microbiology laboratory. METHODS: A hand search of laboratory records for a three-year period (1998-2000) was performed for specimens submitted to the regional diagnostic oral microbiology laboratory based at Glasgow Dental Hospital and School. Data were collected from forms where S. aureus was isolated. These data included demographics, referral source, specimen type, methicillin susceptibility and clinical details. RESULTS: For the period 1998-2000, there were 5,005 specimens submitted to the laboratory. S. aureus was isolated from 1,017 specimens, of which 967 (95%) were sensitive to methicillin (MSSA) and 50 (5%) were resistant to methicillin (MRSA). The 1,017 specimens were provided from 615 patients. MRSA was isolated from 37 (6%) of patients. There was an increasing incidence of S. aureus with age, particularly in the greater than 70 years age group. The most common specimen from which MSSA was isolated was an oral rinse (38%) whilst for MRSA isolates this was a tongue swab (28%). The clinical condition most commonly reported for MSSA isolates was angular cheilitis (22%). Erythema, swelling, pain or burning of the oral mucosa was the clinical condition most commonly reported for MRSA isolates (16%). Patients from whom the MSSA isolates were recovered were most commonly (55%) seen in the oral medicine clinic at the dental hospital, whilst patients with MRSA were more commonly seen in primary care settings such as nursing homes, hospices and general dental practice (51%). CONCLUSION: In line with more recent surveys, this retrospective study suggests that S. aureus may be a more frequent isolate from the oral cavity than hitherto suspected. A small proportion of the S. aureus isolates were MRSA. There were insufficient data available to determine whether the S. aureus isolates were colonising or infecting the oral cavity. However, the role of S. aureus in several diseases of the oral mucosa merits further investigation

Detecting Relic Gravitational Waves in the CMB: Comparison of Planck and Ground-based Experiments

We compare the detection abilities for the relic gravitational waves by two kinds of forthcoming cosmic microwave background radiation (CMB) experiments, space-based Planck satellite and the various ground-based experiments. Comparing with the ground-based experiments, Planck satellite can observe all the CMB power spectra in all the multipole range, but having much larger instrumental noises. We find that, for the uncertainty of the tensor-to-scalar ratio $\Delta r$, PolarBear (II) as a typical ground-based experiment can give much smaller value than Planck satellite. However, for the uncertainty of the spectral index $\Delta n_t$, Planck can give the similar result with PolarBear (II). If combining these two experiments, the value of $\Delta n_t$ can be reduced by a factor 2. For the model with $r=0.1$, the constraint $\Delta n_t=0.10$ is expected to be achieved, which provides an excellent opportunity to study the physics in the very early universe. We also find the observation in the largest scale ($\ell<20$) is very important for constraining the spectral index $n_t$. So it is necessary to combine the observations of the future space-based and ground-based CMB experiments to determine the relic gravitational waves.Comment: 8 pages, 9 figures, 6 table

Cristal phononique piézomagnétique à une dimension : contrôle de la propagation par inductance variable

Cette étude concerne un cristal phononique à une dimension constitué d'un empilement de couches piézomagnétiques identiques. Chaque couche est entourée par une bobine connectée à une inductance extérieure. Les ondes élastiques longitudinales se propageant dans cette structure sont étudiées théoriquement et une expression analytique de l'équation de dispersion est obtenue. Suivant la valeur de l'inductance extérieure, la solution est une onde non dispersive ou dispersive. Dans ce dernier cas, la courbe de dispersion présente une bande de fréquence interdite dont la largeur varie avec la valeur de l'inductance extérieure

The antibacterial activity of acetic acid against biofilm-producing pathogens of relevance to burns patients

Introduction: Localised infections, and burn wound sepsis are key concerns in the treatment of burns patients, and prevention of colonisation largely relies on biocides. Acetic acid has been shown to have good antibacterial activity against various planktonic organisms, however data is limited on efficacy, and few studies have been performed on biofilms. Objectives: We sought to investigate the antibacterial activity of acetic acid against important burn wound colonising organisms growing planktonically and as biofilms. Methods: Laboratory experiments were performed to test the ability of acetic acid to inhibit growth of pathogens, inhibit the formation of biofilms, and eradicate pre-formed biofilms. Results: Twenty-nine isolates of common wound-infecting pathogens were tested. Acetic acid was antibacterial against planktonic growth, with an minimum inhibitory concentration of 0.16-0.31% for all isolates, and was also able to prevent formation of biofilms (at 0.31 %). Eradication of mature biofilms was observed for all isolates after three hours of exposure. Conclusions: This study provides evidence that acetic acid can inhibit growth of key burn wound pathogens when used at very dilute concentrations. Owing to current concerns of the reducing efficacy of systemic antibiotics, this novel biocide application offers great promise as a cheap and effective measure to treat infections in burns patients

Microbiological contamination of cubicle curtains in an out-patient podiatry clinic

<p>Abstract</p> <p>Background</p> <p>Exposure to potential pathogens on contaminated healthcare garments and curtains can occur through direct or indirect contact. This study aimed to identify the microorganisms present on podiatry clinic curtains and measure the contamination pre and post a standard hospital laundry process.</p> <p>Method</p> <p>Baseline swabs were taken to determine colony counts present on cubical curtains before laundering. Curtains were swabbed again immediately after, one and three weeks post laundering. Total colony counts were calculated and compared to baseline, with identification of micro-organisms.</p> <p>Results</p> <p>Total colony counts increased very slightly by 3% immediately after laundry, which was not statistically significant, and declined significantly (p = 0.0002) by 56% one-week post laundry. Three weeks post laundry colony counts had increased by 16%; although clinically relevant, this was not statistically significant. The two most frequent microorganisms present throughout were <it>Coagulase Negative Staphylococcus </it>and <it>Micrococcus </it>species. Laundering was not completely effective, as both species demonstrated no significant change following laundry.</p> <p>Conclusion</p> <p>This work suggests current laundry procedures may not be 100% effective in killing all microorganisms found on curtains, although a delayed decrease in total colony counts was evident. Cubicle curtains may act as a reservoir for microorganisms creating potential for cross contamination. This highlights the need for additional cleaning methods to decrease the risk of cross infection and the importance of maintaining good hand hygiene.</p