How to Support Students in Reading for Meaning

This research explores how to support students in reading for meaning. The purpose of my research was to learn more about how to help students read for meaning and to provide the skills and strategies necessary to support reading for meaning. Further, this research reviews the impact strategies have as a means for comprehension of the text. Data were collected for this study over a four-week period in the form of semi-structured interviews, student artifacts, observations, audio recordings, and field notes. Data were analyzed to determine the most effective ways that students were able to read for meaning

Gene expression changes of particular NMDA receptor subunits in olfactory bulbectomized rat

WSTĘP: Depresja jest zaburzeniem, które dotyka coraz większą część światowej populacji. Prowadzi do spadku aktywności, wycofania z życia rodzinnego i społecznego, a nawet do wystąpienia przewlekłych chorób somatycznych oraz podejmowania prób samobójczych. Dostępne metody terapii zaburzeń depresyjnych, nie przynoszą zadowalających rezultatów, stąd istnieje potrzeba poszukiwania nowych, szybszych i bardziej skutecznych rozwiązań. W badaniach naukowych nad mechanizmem powstawania depresji i w przedklinicznych badaniach skuteczności potencjalnych leków przeciwdepresyjnych, wykorzystuje się zwierzęce modele depresji. Wnioski z doniesień literaturowych ostatniej dekady, sugerują udział układu glutaminianergicznego w etiopatogenezie zaburzeń nastroju, a centrum zainteresowania stał się receptor NMDA. CEL PRACY: Eksperyment podjęty w ramach niniejszej pracy magisterskiej, miał na celu zbadanie wpływu procedury usunięcia opuszek węchowych i/lub przewlekłego stosowania amitryptyliny, na zmianę ekspresji genów kodujących podjednostki NR2A i NR2B receptora NMDA. MATERIAŁY I METODY: Badania przeprowadzono na tkankach szczurów szczepu Sprague Dawley, poddanych procedurze chirurgicznego usunięcia opuszek węchowych. Poziom ekspresji genów (mRNA) NR2A i NR2B badano w dwóch strukturach mózgu: korze czołowej i hipokampie z użyciem łańcuchowej reakcji polimerazy z detekcją w czasie rzeczywistym (Real-Time PCR).WYNIKI: Uzyskane wyniki wskazują na wyraźny spadek ekspresji NR2A i NR2B w hipokampie i brak zmian w korze czołowej szczurów poddanych usunięciu opuszek węchowych. Długotrwałe podawanie amitryptyliny w dawce 10 mg/kg przez okres 14 dni spowodowało w korze czołowej wzrost ekspresji NR2A, a w hipokampie spadek ekspresji NR2B. WNIOSKI: Zarówno procedura usunięcia opuszek węchowych jak i przewlekłe podawanie amitryptyliny, powoduje zmiany w ekspresji genów NR2A i NR2B w poszczególnych strukturach mózgu szczura. Świadczy to o zaangażowaniu układu glutaminianergicznego w patomechanizm i leczenie zaburzeń depresyjnych.INTRODUCTION: Depression is a serious disorder which is often ignored, but concerns a lot of people in the World. It can be main reason of aversion for activity, reduced of familiar and social life and even caused chronic somatic illnesses or suicides. The available therapy for mood disorders are not efficient enough, therefore there is a necessary to search new, faster and more efficient kind of treatment. In scientific researches of depression and preclinical experiments of potential antidepresants it is common to use an animal model of depression. A lot of recent publications suggest the important role of glutamatergic system in pathophysiology of mood disorder. The main point of this hypothesis is NMDA receptor. OBJECT: The aim of this study was to investigate the effect of the olfactory bulbectomy and/or chronic amitryptiline administration on NR2A and NR2B NMDA receptor subunits’ gene expression. MATERIALS AND METHODS: The experiments were carried out on male Sprague Dawley rats. Gene expression was conducted in two brain structures: frontal cortex and hippocampus using Real-Time PCR method. RESULTS: The results showed that the olfactory bulbectomy causes signifficant decrease in expression of NR2A and NR2B in hippocampus, but not in frontal cortex. However 2-weeks administration of amitryptiline in dose 10mg/kg induces changes of gene expression on both of these cerebral structures. In frontal cortex there is a signifficant increased expression of NR2A and decreased expression of NR2B in hippocampus. CONCLUSIONS: Both, olfactory bulbectomy and chronic administration of amitryptiline cause signifficant changes in expression of NR2A and NR2B genes in examined rat brain structures. That results are in agreement with glutamatergic hypothesis of mood disorders

Identification of a resonant target in the free field and buried in a sediment using iterative, single-channel, time reversal

Numerical studies demonstrate enhanced signal-to-noise ratio and convergence to a narrowband signal using iterative time reversal of the monostatic scattered return from a resonating target [Pierson, David M., “Buried Object Detection Using TimeReversed Acoustics,” PhD Dissertation, North Carolina State University, 2003]. The center frequency of the converged-upon signal is a resonance frequency of the target whose value can be used for classification and identification purposes. This technique could offer a straightforward means for enhancing target return levels in a noisy or cluttered environment using existing sonar systems. We report results from scaled experiments performed in a water tank using broad band (Q~2) piston transducers operating in the 500 kHz – 2 MHz frequency range. The target is a 6.35-mm diameter hollow steel sphere suspended in the free field and buried at different depths in a mediumgrain sand layer. The procedure consists of exciting the target with a broadband pulse, digitizing the echo return, reversing the data stream in time, and using this signal as the source waveform for the next interrogation pulse. Free field results indicate that the spectrum of the echo rapidly converges to a frequency corresponding to a resonant mode of the target. The signal to noise ratios of targets buried in sand are enhanced as the iterations converge to the strongest available target resonance

Identification of a resonant target in the free field and buried in a sediment using iterative, single-channel, time reversal

Numerical studies demonstrate enhanced signal-to-noise ratio and convergence to a narrowband signal using iterative time reversal of the monostatic scattered return from a resonating target [Pierson, David M., “Buried Object Detection Using TimeReversed Acoustics,” PhD Dissertation, North Carolina State University, 2003]. The center frequency of the converged-upon signal is a resonance frequency of the target whose value can be used for classification and identification purposes. This technique could offer a straightforward means for enhancing target return levels in a noisy or cluttered environment using existing sonar systems. We report results from scaled experiments performed in a water tank using broad band (Q~2) piston transducers operating in the 500 kHz – 2 MHz frequency range. The target is a 6.35-mm diameter hollow steel sphere suspended in the free field and buried at different depths in a mediumgrain sand layer. The procedure consists of exciting the target with a broadband pulse, digitizing the echo return, reversing the data stream in time, and using this signal as the source waveform for the next interrogation pulse. Free field results indicate that the spectrum of the echo rapidly converges to a frequency corresponding to a resonant mode of the target. The signal to noise ratios of targets buried in sand are enhanced as the iterations converge to the strongest available target resonance

Sensing a buried resonant object by single-channel time reversal

Scaled laboratory experiments are conducted to assess the efficacy of iterative, single-channel time reversal for enhancement of monostatic returns from resonant spheres in the free field and buried in a sediment phantom. Experiments are performed in a water tank using a broad-band piston transducer operating between 0.4 and 1.5 MHz and calibrated using free surface reflections. Solid and hollow metallic spheres, 6.35 mm in diameter, are buried in a consolidation of 128-mum-mean-diameter spherical glass beads. The procedure consists of exciting the target object with a broadband pulse, sampling the return using a finite time window, reversing the signal in time, and using this reversed signal as the source waveform for the next interrogation. Results indicate that the spectrum of the returns rapidly converges to the dominant mode in the backscattering response of the target. Signal-to-noise enhancement of the target echo is demonstrated for a target at several burial depths. Images generated by scanning the transducer over the location of multiple buried targets demonstrate the ability of the technique to distinguish between targets of differing type and to yield an enhancement of different modes within the response of a single target as a function of transducer position and processing bandwidth. </p

Sensing a buried resonant object by single-channel time reversal

Scaled laboratory experiments are conducted to assess the efficacy of iterative, single-channel time reversal for enhancement of monostatic returns from resonant spheres in the free field and buried in a sediment phantom. Experiments are performed in a water tank using a broad-band piston transducer operating between 0.4 and 1.5 MHz and calibrated using free surface reflections. Solid and hollow metallic spheres, 6.35 mm in diameter, are buried in a consolidation of 128-mum-mean-diameter spherical glass beads. The procedure consists of exciting the target object with a broadband pulse, sampling the return using a finite time window, reversing the signal in time, and using this reversed signal as the source waveform for the next interrogation. Results indicate that the spectrum of the returns rapidly converges to the dominant mode in the backscattering response of the target. Signal-to-noise enhancement of the target echo is demonstrated for a target at several burial depths. Images generated by scanning the transducer over the location of multiple buried targets demonstrate the ability of the technique to distinguish between targets of differing type and to yield an enhancement of different modes within the response of a single target as a function of transducer position and processing bandwidth. </p

The Investigation of the Effects of Gravity on Single Bubble Sonoluminescence

In single bubble following it's rapid collapse each cycle of oscillation of an ultrasonic field. Since widely varying length and time scales affect the bubble dynamics and optical emission processes, it is difficult to anticipate the importance of the effects of gravity present for observations on earth. Our bubble is driven in an acoustically resonating cavity at it's first harmonic mode. The acoustical radiation pressure (Bjerknes force) will then keep it suspended in the center near the pressure antinode. When driven in a region where the diffusive processes balance the bubble it acts in a nonlinear but regular way, emitting a short (approx. 200ps) burst of light each acoustic cycle. Balancing the Bjerknes force with buoyancy, as in, we can see that the bubble should be displaced from the velocity node approximately 20m at normal gravity. Therefore, water flows past the bubble at the time of collapse. Gravitation also changes the ambient pressure at the bubble's location, as Delta.P = rho.g.h this gives a change of approximately -0.5% in our experiment when going from 1.8g to 0g. Studies of ambient pressure changes were also done in order to assess these effects. Inside a pressure sealed chamber a spherical glass cell is filled with distilled water which has been degassed to 120mmHg. A bubble is then trapped in the center and driven by a piezoelectric transducer at 32.2kHz attached to the side of the cell. An optical system is then set up to take strobbed video images along and light emission data simultaneously. Temperature, pressure, drive voltage, and listener voltage are also monitored. PMT output in Volts The radii of the bubbles for both experiment s are fit using the Rayleigh-Plesset equation and the acoustic drive amplitude and the ambient bubble radius are found. There is little change in the acoustic drive amplitude as we expect, since we are not varying the drive voltage. However. the ambient bubble radius goes up considerably. These changes (increased light output, increased maximum bubble radius, and increased ambient bubble radius) are also observed when the ambient pressure is varied in the laboratory by an amount similar to that due to gravitation. The changes in the ambient bubble radius and light output with a change in ambient pressure are predicted by the "dissociation hypothesis" and have been observed by other groups in the laboratory. It seems clear that buoyancy's effect on light output and bubble radius, are at best on the same order as the effects of ambient pressure