Effects of High-Probability Request Sequences on Preschoolers' Compliance and Disruptive Behavior

A high-probability request sequence was implemented with three preschool children with developmental delays within their classroom during typical activities. A multiple baseline design across subjects was used to evaluate the effects of the high-probability request sequence on compliant responding to low-probability requests and the occurrence of disruptive behavior. Results of the study indicate that the use of the high-probability request sequence was effective in increasing compliant responding to low-probability requests delivered by two different trainers for all children. No increases in disruptive behavior were noted as a result of using the high-probability request sequence. When the high-probability request sequence was withdrawn, compliant responding to low-probability requests was maintained for all children across time and in different settings.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44805/1/10864_2004_Article_416137.pd

COMPOSITE SILICON/METAL NANOSTRUCTURES BY METAL-ASSISTED ETCHING FOR CHEMI-TRANSISTOR SENSORS

This work reports on the use of composite silicon/metal nanostructures (cSiMN) prepared by Metal Assisted Etch-ing (MAE) as highly sensitive material for the fabrication of chemi-transistor gas sensors operating at room tem-perature. As a case-of-study, we investigate the integration of composite silicon/gold nanostructures (cSiAuN) synthesized by MAE in solid-state transistors, namely junction-field-effect transistors (JFET), aimed at the detec-tion of nitrogen dioxide (NO2) down to 100-part-per-billion (ppb). The resulting chemi-transistor sensor, namely cSiAuJFET (Composite Silicon Gold JFET), consists of a p-channel JFET in which the cSiAuN layer is placed on top of the p-channel and acts as a sensing gate. A thorough electrical characterization, both static and dynamic, of the cSiAuJFET sensor is performed in NO2 at concentration of hundreds ppb using synthetic air as carrier gas. Notably, the cSiAuJFET sensors show fast and reliable response to NO2 in the range 100-500 ppb without signifi-cant aging effects, in terms of response times and sensitivity value, up to a few days of continuous operation

The effects of a classroom manager role on the social interaction patterns and social status of withdrawn kindergarten students.

We examined the effects of assigning a classroom manager's role on the frequency of social interactions and the sociometric standing of three withdrawn kindergarten students. Results showed that when the three socially withdrawn students were placed in the manager's role they substantially increased the frequency of their positive social initiations during free-play time, were the recipients of many more positive and significantly fewer negative social bids from their peers, were rated more favorably by their classmates on a sociometric rating scale, and were selected more frequently as best friends by their peers. In addition, follow-up data suggested partial maintenance of treatment effects when students no longer occupied manager positions

Natural and anthropogenic features influencing water quality in NE Buenos Aires, Argentina

9 páginas, 5 figuras, 5 tablas, 2 mapas.-- Trabajo presentado en el VI ALHSUD- XXXII AIH Congreso Mar del Plata 2002.This work study water quality of the Pergamino River watershed in the Undulated Pampa in the northeast of the Argentinean Province of Buenos Aires. Temperature, pH, specific conductivity, Na, K, Mg, Ca, SO42Cl; HCO3, NO3, Si, Ag, Al, As, B, Ba, br, Cd, Co, Cr, Cu, Fe, Hg, Li, Mn, Mo, Ni, P, Pb, Se, Tl, U, V, Zn, and the (omega 18) O and (omega2)H isotope ratios were monitored in eighteen sampling stations. Groundwater and surface water are of sodium bicarbonate type, evolving to sodium sulfate-chloride type in the case of surface water.This work has been partially funded through the Proyect T657 from University of Buenos Aires.Peer reviewe

Chemi-Transistor Sensors based on Composite Silicon/Gold Nanostructures Prepared by Metal Assisted Etching

The ability to fabricate micro [1] and nanostructures [2] on silicon (Si) with the possibility to dope the final porous structures with noble metal NPs (e.g. gold, silver), using Metal-Assisted Etching (MAE)[3] is a unique advantage of MAE as to sensing applications. Over the standard fabrication technique such as anodic etching [4], MAE represents a low-cost room-temperature method for the synthesis of Si-based nanomaterials with peculiar sensing features, in terms of sensitivity and selectivity, towards specific gases, by bringing the catalytic properties and distinctive selectivity of the metals nanoparticles[5] and the widely tunable bandgap of the porous silicon into play. Here the prospect of using composite silicon/gold nanostructures (cSiAuN) prepared by MAE, gold-assisted, as highly sensitive material for adsorption of Nitrogen Dioxide (NO2) is proposed, examining the controllable high-yield integration of the material into solid-state devices. The controllable fabrication of the final nanostructures achieved by MAE approach leads to the fabrication of cSiAuN with high degree of control in terms of morphology of the pores and depth of the matrix, with enhanced sensing capabilities, which justifies their successful application in the preparation of chemi-transistor sensors, such as field-effect transistors, FETs, to be employed for gas sensing applications. As a case-of-study, we investigate the effective method for controllable integration of composite cSiAuN between electrodes of junction-field-effect transistors (JFET), aimed at the detection of NO2 down to 100 parts-per-billion (ppb). The resulting chemi-transistor sensor, cSiAuJFET (Composite Silicon Gold JFET), consists of a p-channel JFET in which the cSiAuN material is placed on top of the p-channel and acts as an extra floating gate and are responsible for the sensing capability of the JFET device. The cSiAuJFET sensors operate at room temperature and shows fast and reliable response to NO2 in the range 100-500 ppb without significant aging effects, in terms of baseline drift, response times, and sensitivity value, up to two days of continuous operation. The achieved approach presented in this work represent a guide for the possibility of employing MAE for gas sensing applications. [1] A. G. F. Owen J. Hildreth, Ching Ping Wong, ACSNano 2012, 6, 9. [2] L. Boarino, D. Imbraguglio, E. Enrico, N. De Leo, F. Celegato, P. Tiberto, N. Pugno, G. Amato, physica status solidi (a) 2011, 208, 1412. [3] Peng K. Q. et al. Advanced Materials 2002, 14, 1164. [4] G. M. Lazzerini, L. M. Strambini, G. Barillaro, Sci Rep 2013, 3, 1161. [5] L. C. Nicola Cioffi, Eliana Ieva, Rosa Pilolli, Nicoletta Ditaranto, Maria Daniela Angione, Serafina Cotrone, Kristina Buchholt, Anita Lloyd Spetz, Luigia Sabbatini, Luisa Torsi, Electrochimica Acta 2011, 56

Genetic Screening in a Large Cohort of Italian Patients Affected by Primary Lymphedema Using a Next Generation Sequencing (NGS) Approach

Primary lymphedema is a rare inherited condition characterized by swelling of body tissues caused by accumulation of fluid, especially in the lower limbs. In many patients, primary lymphedema has been associated with variations in a number of genes involved in the development and maintenance of the lymphatic system. In this study, we performed a genetic screening in patients affected by primary lymphedema using a next generation sequencing (NGS) approach. With this technology, based on a custom-made oligonucleotide probe library, we were able to analyze simultaneously in each patient all the coding exons of 10 genes (FLT4, FOXC2, CCBE1, GJC2, MET, HGF, GATA2, SOX18, VEGFC, KIF11) associated with primary lymphedema. In the study population, composed of 45 familial and 71 sporadic cases, we identified the presence of rare variants with a potential pathogenic effect in 33% of subjects. Overall, we found a total of 36 different rare nucleotidic alterations, 30 of which had not been previously described. Among these, we identified 23 mutations that we considered most likely to be disease causing. Patients with an FLT4 or FOXC2 alteration accounted for the largest percentage of the sample, followed by MET, HGF, KIK11, GJC2 and GATA2. No alterations were identified in SOX18, VEGFC, and CCBE1 genes. In conclusion, we showed that NGS technology can be successfully applied to perform molecular screening of lymphedema-associated genes in large cohort of patients with a reasonable effort in terms of cost, work, and time

Facilitating transition times with handicapped preschool children: a comparison between peer-mediated and antecedent prompt procedures.

We examined the effects of a peer-mediated versus an antecedent prompt condition on the rate of independent movement and appropriate behavior of handicapped preschool children during three classroom transition times. Using an alternating treatments design, results showed that each treatment condition yielded increases in target behaviors; however, the antecedent prompt condition was superior during all three transition settings. In addition, teacher prompts to these children were significantly reduced during the intervention conditions, indicating that the children were making these transitions more independently