564 research outputs found
Recommended from our members
Enhancing self esteem and achievement through group guidance activities.
The main purpose of this research was to determine whether the self-esteem and school performance (academic grades, scores in effort and conduct, attendance) of sixth grade students could be improved through exposure to ten weeks, 45 minutes per week, of a group guidance program. The curriculum was composed and designed by the researcher drawing from several sources (Simon, Howe, and Kirshenbaum, 1972; Simon, 1973; Anderson and Henner, 1972; Canfield and Wells, 1976). The emphasis of this treatment program was on improving students\u27 self-esteem through the reflected appraisal of a significant other (guidance counselor) while engaging in activities that foster self-awareness. The data presented was collected using a sample of 96 sixth grade students (46 experimental and 50 control) from an upper middle class community in central New England. Subjects were randomly assigned by the school principal to either of the two treatment conditions. The control group participated in ten weeks, 90 minutes per week, of an introductory foreign language (French) program aimed at providing an enjoyable and successful foreign language experience to sixth grade students. All subjects were pretested and posttested using the Coopersmith (1967) Self Esteem Inventory. Performance scores were also collected for both groups before and after treatment. The results indicated that the measured level of self-esteem and school performance were not significantly enhanced as a result of the group guidance activities. Other relevant information gleaned from the results found that female students obtained a significantly lower level of measured self-esteem on the pretest and that their school performance scores were higher in every area and significantly higher (p \u3c .05) in science, social studies and conduct on the posttest. Also female students in the experimental group showed a greater increase (more than 2 times greater) than the males in the experimental group or the male or female students in the control group. Finally, there were significant differences in the measured level of self-esteem and school performance associated with the students\u27 level of instruction. Students in the top level obtained a significantly higher measured level of self-esteem and school performance than students in the lower levels
Cardiolipin modulates allosterically peroxynitrite detoxification by horse heart cytochrome c
Biosensing platform combining label-free and labelled analysis using Bloch surface waves
Bloch surface waves (BSW) propagating at the boundary of truncated photonic crystals (1D-PC) have emerged as an attractive approach for label-free sensing in plasmon-like sensor configurations. Due to the very low losses in such dielectric thin film stacks, BSW feature very low angular resonance widths compared to the surface plasmon resonance
(SPR) case. Besides label-free operation, the large field enhancement and the absence of quenching allow utilizing BSW coupled fluorescence detection to additionally sense the presence of fluorescent labels. This approach can be adapted to the case of angularly resolved resonance detection, thus giving rise to a combined label-free / labelled biosensor
platform. It features a parallel analysis of multiple spots arranged as a one-dimensional array inside a microfluidic channel of a disposable chip. Application of such a combined biosensing approach to the detection of the Angiopoietin-2 cancer biomarker in buffer solutions is reported
Effect of 5′-methylthioadenosine on gene action during heat shock in Drosophila melanogaster
Compact Pulsed-Power System for Transient Plasma Ignition
The article of record as published may be found at http://dx.doi.org10.1109/TPS.2009.2024672The use of a compact solid-state pulse generator and compact igniters for transient plasma ignition in a pulse detonation engine (PDE) is reported and compared with previous results using a pseudospark pulse generator and threaded rod electrode. Transient plasma is attractive as a technology for the ignition of PDEs and other engine applications because it results in reductions in ignition delay and has been shown to ignite leaner mixtures which allows for lower specific fuel consumption, high-repetition rates, high-altitude operation, and reduced NOx emissions. It has been applied effectively to the ignition of PDEs as well as internal combustion engines. Nonequilibrium transient plasma discharges are produced by applying high-voltage nanosecond pulses that generate streamers, which generate radicals and other electronically excited species over a volume. The pulse generator used is in this experiment is capable of delivering 180 mJ into a 200-Ω load, in the form of a 60-kV 12-ns pulse. Combined with transient plasma igniters comparable with traditional spark plugs, the system was successfully tested in a PDE, resulting in similar ignition delays to those previously reported while using a smaller electrode geometry and delivering an order of magnitude less energy.Office of Naval Researc
Tactile sensing and control of robotic manipulator integrating fiber Bragg grating strain-sensor
Tactile sensing is an instrumental modality of robotic manipulation, as it provides information that is not accessible via remote sensors such as cameras or lidars. Touch is particularly crucial in unstructured environments, where the robot’s internal representation of manipulated objects is uncertain. In this study we present the sensorization of an existing artificial hand, with the aim to achieve fine control of robotic limbs and perception of object’s physical properties. Tactile feedback is conveyed by means of a soft sensor integrated at the fingertip of a robotic hand. The sensor consists of an optical fiber, housing Fiber Bragg Gratings (FBGs) transducers, embedded into a soft polymeric material integrated on a rigid hand. Through several tasks involving grasps of different objects in various conditions, the ability of the system to acquire information is assessed. Results show that a classifier based on the sensor outputs of the robotic hand is capable of accurately detecting both size and rigidity of the operated objects (99.36 and 100% accuracy, respectively). Furthermore, the outputs provide evidence of the ability to grab fragile objects without breakage or slippage e and to perform dynamic manipulative tasks, that involve the adaptation of fingers position based on the grasped objects’ condition
Conversion of cytochrome c into a peroxidase: inhibitory mechanisms and implication for neurodegenerative diseases.
A further function of cytochrome c (cyt c), beyond respiration, is realized outside mitochondria in the apoptotic program. In the early events of apoptosis, the interaction of cyt c with a mitochondrion-specific phospholipid, cardiolipin (CL), brings about a conformational transition of the protein and acquirement of peroxidase activity. The hallmark of cyt c with peroxidase activity is its partial unfolding accompanied by loosening of the Fe sixth axial bond and an enhanced access of the heme catalytic site to small molecules like H2O2. To investigate the peroxidase activity of non-native cyt c, different forms of the protein were analyzed with the aim to correlate their structural features with the acquired enzymatic activity and apoptogenic properties (wt cyt c/CL complex and two single cyt c variants, H26Y and Y67H, free and bound to CL). The results suggest that cyt c may respond to different environments by changing its fold thus favouring the exertion of different biological functions in different pathophysiological cell conditions. Transitions among different conformations are regulated by endogenous molecules such as ATP and may be affected by synthetic molecules such as minocycline, thus suggesting a mechanism explaining its use as therapeutic agent impacting on disease-associated oxidative and apoptotic mechanisms
The effects of ATP and sodium chloride on the cytochrome c-cardiolipin interaction: the contrasting behavior of the horse heart and yeast proteins
The 40s Omega-loop plays a critical role in the stability and the alkaline conformational transition of cytochrome c
The structural and redox properties of a non-covalent complex reconstituted upon mixing two non-contiguous fragments of horse cytochrome c, the residues 1 - 38 heme-containing N-fragment with the residues 57 - 104 C-fragment, have been investigated. With respect to native cyt c, the complex lacks a segment of 18 residues, corresponding, in the native protein, to an omega ( W)loop region. The fragment complex shows compact structure, native-like alpha-helix content but a less rigid atomic packing and reduced stability with respect to the native protein. Structural heterogeneity is observed at pH 7.0, involving formation of an axially misligated low-spin species and consequent partial displacement of Met80 from the sixth coordination position of the heme-iron. Spectroscopic data suggest that a lysine ( located in the Met80-containing loop, namely Lys72, Lys73, or Lys79) replaces the methionine residue. The residues 1 - 38/57 - 104 fragment complex shows an unusual biphasic alkaline titration characterized by a low (pK(a1)= 6.72) and a high pK(a)-associated state transition (pK(a2)= 8.56); this behavior differs from that of native cyt c, which shows a monophasic alkaline transition ( pK(a)= 8.9). The data indicate that the 40s Omega-loop plays an important role in the stability of cyt c and in ensuring a correct alkaline conformational transition of the protein
- …