bluuebunny/crossref_metadata_2025 huggingface dataset:
Two-Dimensional Electron Gas Transport Properties in AlGaN/(In)GaN/AlGaN Double-Heterostructure Field Effect Transistors
Authors: Maeda Narihiko , Saitoh Tadashi , Tsubaki Kotaro , Nishida Toshio , Kobayashi Naoki
Published: September 2012

Two-dimensional electron gas transport properties have been investigated in nitride double-heterostructures. A striking effect has been observed that the two-dimensional electron gas mobility has been drastically enhanced in the AlGaN/GaN/AlGaN doubleheterostructure, compared with that in the conventional AlGaN/GaN singleheterostructure. The observed mobility enhancement has been shown to be mainly due to the enhanced polarization-induced electron confinement in the double-heterostructure, and additionally due to the improvement of the interface roughness in the structure. Device operation of an AlGaN/GaN/AlGaN double-heterostructure field effect transistor has been demonstrated: a maximum transconductance of 180 mS/mm has been obtained for a 0.4 mm-gate-length device. In the double-heterostructure using InGaN channel, the increased capacity for the two-dimensional electron gas has been observed. The AlGaN/(In)GaN/AlGaN double-heterostructures are effective for improving the electron transport properties.
High-Temperature Reliability of GaN Electronic Devices
Authors: Yoshida Seikoh , Suzuki Joe
Published: September 2012

High-quality GaN was grown using gas-source molecular-beam epitaxy (GSMBE). The mobility of undoped GaN was 350 cm2/Vsec and the carrier concentration was 6×1016 cm−3 at room temperature. A GaN metal semiconductor field-effect transistor (MESFET) and an n-p-n GaN bipolar junction transistor (BJT) were fabricated for hightemperature operation. The high-temperature reliability of the GaN MESFET was also investigated. That is, the lifetime of the FET at 673 K was examined by continuous current injection at 673 K. We confirmed that the FET performance did not change at 673 K for over 1010 h. The aging performance of the BJT at 573 K was examined during continuous current injection at 573 K for over 850 h. The BJT performance did not change at 573 K. The current gain was about 10. No degradation of the metalsemiconductor interface was observed by secondary ion-mass spectrometry (SIMS) and transmission electron microscopy (TEM). It was also confirmed by using Si-ion implantation that the contact resistivity of the GaN surface and electrode materials could be lowered to 7×10-6 ohmcm2.
TEM Study of Bulk AlN Growth by Physical Vapor Transport
Authors: Sarney W.L. , Salamanca-Riba L. , Hossain T. , Zhou P. , Jayatirtha H.N. , Kang H.H. , Vispute R.D. , Spencer M. , Jones K.A.
Published: September 2012

We are attempting to grow bulk AlN that would be suitable as a substrate for nitride film growth. Bulk AlN films were grown by physical vapor transport on 3.5° offaxis and on-axis 6H SiC seed crystals and characterized by TEM, x-ray-diffraction, Auger electron microscopy, and SEM. TEM images show that the bulk AlN does not have the columnar structure typically seen in AlN films grown by MOCVD. Although further optimization is required before the bulk AlN is suitable as a substrate, we find that the structural characteristics achieved thus far indicate that quality bulk AlN substrates may be obtained in the future.
The Role of the Multi Buffer Layer Technique on the Structural Quality of GaN
Authors: Benamara M. , Liliental-Weber Z. , Mazur J.H. , Swider W. , Washburn J. , Iwaya M. , Akasaki I. , Amano H.
Published: September 2012

Successive growth of thick GaN layers separated by either LT-GaN or LT-AlN interlayers have been investigated by transmission electron microscopy techniques. One of the objectives of this growth method was to improve the quality of GaN layers by reducing the dislocation density at the intermediate buffer layers that act as barriers to dislocation propagation. While the use of LT-AlN results in the multiplication of dislocations in the subsequent GaN layers, the LT-GaN reduces dislocation density. Based upon Burgers vector analysis, the efficiency of the buffer layers for the propagation of the different type of dislocations is presented. LT-AlN layer favor the generation of edge dislocations, leading to a highly defective GaN layer. On the other hand, the use of LT-GaN as intermediate buffer layers appears as a promising method to obtain high quality GaN layer.
MOVPE Growth of Quaternary (Al,Ga,In)N for UV Optoelectronics
Authors: Han Jung , Figiel Jeffrey J. , Petersen Gary A. , Myers Samuel M. , Crawford Mary H. , Banas Michael A. , Hearne Sean J.
Published: September 2012

We report the growth and characterization of quaternary AlGaInN. A combination of photoluminescence (PL), high-resolution x-ray diffraction (XRD), and Rutherford backscattering spectrometry (RBS) characterizations enables us to explore the contours of constant- PL peak energy and lattice parameter as functions of the quaternary compositions. The observation of room temperature PL emission at 351nm (with 20% Al and 5% In) renders initial evidence that the quaternary could be used to provide confinement for GaInN (and possibly GaN). AlGaInN/GaInN MQW heterostructures have been grown; both XRD and PL measurements suggest the possibility of incorporating this quaternary into optoelectronic devices.
Homo-Epitaxial Growth on Misoriented GaN Substrates by MOCVD
Authors: Zauner A.R.A. , Schermer J.J. , Enckevort W.J.P. van , Kirilyuk V. , Weyher J.L. , Grzegory I. , Hageman P.R. , Larsen P.K.
Published: September 2012

The N-side of GaN single crystals with off-angle orientations of 0°, 2°, and 4° towards the [1010] direction was used as a substrate for homo-epitaxial MOCVD growth. The highest misorientation resulted in a reduction of the density of grown hillocks by almost two orders of magnitude as compared with homo-epitaxial films grown on the exact (0001) surface. The features still found on the 4° misoriented sample after growth can be explained by a model involving the interaction of steps, introduced by the misorientation and the hexagonal hillocks during the growth process.
AlN Wafers Fabricated by Hydride Vapor Phase Epitaxy
Authors: Nikolaev Andrey , Nikitina Irina , Zubrilov Andrey , Mynbaeva Marina , Melnik Yuriy , Dmitriev Vladimir
Published: September 2012

We report on AlN wafers fabricated by hydride vapor phase epitaxy (HVPE). AlN thick layers were grown on Si substrates by HVPE. Growth rate was up to 60 microns per hour. After the growth of AlN layers, initial substrates were removed resulting in free-standing AlN wafers. The maximum thickness of AlN layer was about 1 mm. AlN free-standing single crystal wafers with a thickness ranging from 0.05 to 0.8 mm were studied by x-ray diffraction, transmission electron microscopy, optical absorption, and cathodoluminescence.
Growth of Crack-Free Thick AlGaN Layer and its Application to GaN-Based Laser Diode
Authors: Akasaki I. , Kamiyama S. , Detchprohm T. , Takeuchi T. , Amano H.
Published: September 2012

In the field of group-III nitrides, hetero-epitaxial growth has been one of the most important key technologies. A thick layer of AlGaN alloy with higher AlN molar fraction is difficult to grow on sapphire substrate, because the alloy layer is easily cracked. It is thought that one cause of generating cracks is a large lattice mismatch between an AlGaN and a GaN, when AlGaN is grown on the underlying GaN layer. We have achieved crack-free Al0.07Ga0.93N layer with the thickness of more than 1mm using underlying Al0.05Ga0.95N layer. The underlying Al0.05Ga0.95N layer was grown directly on sapphire by using the lowtemperature-deposited buffer layer (LT-buffer layer). Since a lattice mismatch between the underlying Al0.05Ga0.95N layer and upper Al0.07Ga0.93N layer is relatively small, the generation of cracks is thought to be suppressed. This technology is applied to a GaN-based laser diode structure, in which thick n-Al0.07Ga0.93N cladding layer grown on the Al0.05Ga0.95N layer, improves optical confinement and single-robe far field pattern in vertical direction.
High-Quality AlGaN/GaN Grown on Sapphire by Gas-Source Molecular Beam Epitaxy using a Thin Low-Temperature AlN Layer
Authors: Jurkovic M. J. , Li L.K. , Turk B. , Wang W. I. , Syed S. , Simonian D. , Stormer H. L.
Published: September 2012

Growth of high-quality AlGaN/GaN heterostructures on sapphire by ammonia gassource molecular beam epitaxy is reported. Incorporation of a thin AlN layer grown at low temperature within the GaN buffer is shown to result in enhanced electrical and structural characteristics for subsequently grown heterostructures. AlGaN/GaN structures exhibiting reduced background doping and enhanced Hall mobilities (2100, 10310 and 12200 cm2/Vs with carrier sheet densities of 6.1 × 1012 cm−2, 6.0 × 1012 cm−2, and 5.8 × 1012 cm−2 at 300 K, 77 K, and 0.3 K, respectively) correlate with dislocation filtering in the thin AlN layer. Magnetotransport measurements at 0.3 K reveal well-resolved Shubnikov-de Haas oscillations starting at 3 T.
High Quality AlN and GaN Grown on Si(111) by Gas Source Molecular Beam Epitaxy with Ammonia
Authors: Nikishin Sergey A. , Faleev Nikolai N. , Antipov Vladimir G. , Francoeur Sebastien , Peralta Luis Grave de , Seryogin George A. , Holtz Mark , Prokofyeva Tat'yana I. , Chu S. N. G. , Zubrilov Andrei S. , Elyukhin Vyacheslav A. , Nikitina Irina P. , Nikolaev Andrei , Melnik Yuriy , Dmitriev Vladimir , Temkin Henryk
Published: September 2012

We describe the growth of high quality AlN and GaN on Si(111) by gas source molecular beam epitaxy (GSMBE) with ammonia (NH3). The initial nucleation (at 1130-1190K) of an AlN monolayer with full substrate coverage resulted in a very rapid transition to two-dimensional (2D) growth mode of AlN. The rapid transition to the 2D growth mode of AlN is essential for the subsequent growth of high quality GaN, and complete elimination of cracking in thick ( > 2 μm) GaN layers. We show, using Raman scattering (RS) and photoluminescence (PL) measurements, that the tensile stress in the GaN is due to thermal expansion mismatch, is below the ultimate strength of breaking of GaN, and produces a sizable shift in the bandgap. We show that the GSMBE AlN and GaN layers grown on Si can be used as a substrate for subsequent deposition of thick AlN and GaN layers by hydride vapor phase epitaxy (HVPE).
Mg Segregation, Difficulties of P-Doping in GaN
Authors: Liliental-Weber Z. , Benamara M. , Swider W. , Washburn J. , Grzegory I. , Porowski S. , Dupuis R.D. , Eiting C.J.
Published: September 2012

Transmission electron microscopy has been used to study defects formed in Mg-doped GaN crystals. Three types of crystals have been studied: bulk crystals grown by a high pressure and high temperature process with Mg added to the Ga solution and two types of crystals grown by metal-organic chemical vapor deposition (MOCVD) where Mg was either delta-doped or continuously doped. Spontaneous ordering was observed in bulk crystals. The ordering consists of Mg rich planar defects on basal planes separated by 10.4 nm and occurs only for growth in the N to Ga polar direction (000 1N polarity). These planar defects exhibit the characteristics of stacking faults with a shift vector of a 1/3 [1100] +c/2 but some other features identify these defects as inversion domains. Different type of defects were formed on the opposite site of the crystal (Ga to N polar direction), where the growth rate is also an order of magnitude faster compared to the growth with N-polarity. These defects are three-dimensional: pyramidal and rectangular, empty inside with Mg segregation on internal surfaces. The same types of defects seen for the two growth polarities in the bulk crystals were also observed in the MOCVD grown GaN samples with Mg delta doping, but were not observed in the crystals where Mg was added continuously.
The Sensitization of Nanoporous TiO2 Electrodes by Porphyrin Derivatives with Different Substituents
Authors: Pan Kai , Liu Zhaoyue , Xü Jinjie , Yu Miao , Wang Dejun , Bai Yubai , Li Tiejin
Published: September 2012

Nanoporous TiO2 electrodes were sensitized by different porphyrin derivatives, terahydroxyphenyl porphyrin (THPP) and tera-carboxylphenyl porphyrin (TCPP). Both kinds of sensitized electrodes were characterized by UV-vis, XRD and XPS. The results showed that the interaction between TiO2 and TCPP was stronger than that between TiO2 and THPP. Both kinds of the sensitized electrodes were assembled to photoelectrochemical cells. The photocurrent responses of the photoelectrochemical cell under different incident illumination directions were different significantly. The overall light-to-electric energy conversion yield (η) of TCPPsensitized cell was 0.11%, while the conversion efficiency of THPP-sensitized cell was 0.06%.
Nano Cuprous Oxides Film Prepared by Magnetron Sputtering
Authors: Lu Yang-Ming , Chen Jun-Yuan , Wey Tzuu-Shaang
Published: September 2012

Cuprous oxide (Cu2O) is a direct-gap semiconductor with band-gap energy of 2.0 eV and has been extensively investigated as a candidate for a photovoltaic material. However, practical applications have not been achieved to date due to the difficulty in controlling its physical properties. We have investigated the controllability of the formation of pure Cu2O thin films deposited by the reactive DC sputtering method and analysis by XPS and Raman spectrometer to identify the Cu+1 in the cuprous oxide. The formation of pure Cu2O films is not only dependent on the substrate temperature but also strongly effected by the oxygen and argon flow rate ratio. When the substrate temperature was kept constant at 100°C and varied the oxygen and argon flow rate ratio from 3ml/min to 10ml/min, it is found a mixture of Cu2O and CuO phases is formed. At the flow rate of oxygen to 5ml/min, the pure and single phase of Cu2O is formed. Further increasing the oxygen flow rate, the phase is changed to be the CuO phase. The crystallity is improved as increasing the substrate temperature. The electrical resistivity of Cu2O obtained in this study is about 316 ohm-cm at 100°C substrate temperature and 2.66Pa condition. The dependence of cupper oxides resistivity is not only on the substrate temperature and reactive gases but also on the sputter pressure. Because the characteristic resistivity values change with sputter pressure variation due to different phase compositions forming in the films. The lowest resistivity of Cu2O film is obtained when the Cu2O single phase exists in the films.
Electrical and Morphological Characterization of Electrochemically Deposited ZnO/dye Hybrid Films
Authors: Reemts J. , Parisi J. , Kittel A.
Published: September 2012

Dye sensitized solar cells of the Graetzel type are usually fabricated with TiO2 covered with dye after its synthesis as one electrode. ZnO is, aside from TiO2, a promising alternative semiconducting material for solar energy conversion due to its enhanced surface area and a strong attachment of non-aggregated sensitizer dyes. We investigate ZnO/dye electrodes where the dye is already added during the electro-deposition process of the ZnO. We examine the influence of the dye species and the dye concentration on the surface morphology by means of atomic force and scanning electron microscopy imaging. The electrical properties of the films are characterized by means of current-voltage measurements. In order to study the integral properties of the charge carrier transport in the lateral direction of the film we characterized ZnO thin films electro-deposited across an insulating gap between two microstructured electrodes made of gold.
Non-Steady State Operation of Polymer/TiO2 Photovoltaic Devices
Authors: Kirov Kiril R. , Burlakov Victor M. , Carey Michelle J. , Henry Bernard M. , Xie Zhibin , Grovenor Christopher R. M. , Assender Hazel E. , Webster Graham R. , Briggs G. Andrew D.
Published: September 2012

Polymer/TiO2 composite solar cells (CSCs) are currently being investigated by academic research groups and industrial companies due to the prospect of achieving good power conversion efficiencies and lifetime stability at a low production cost. We present data of the initial period of operation (up to several hours) of such devices, which show that during this period the CSCs operate in a non-steady state regime. The transient behaviour is accounted for using an equivalent circuit model (ECM) of the photovoltaic device with time-dependent resistors.
Improved EDLC Characteristics of the CNTs Grown on the Nanoporous Alumina Templates
Authors: Wen Sun , Jung Mi , Joo Oh-Shim , Mho Sun-il
Published: September 2012

The specific capacitance of the carbon nanotube (CNT) electrode can be increased by using nanoporous alumina templates with the high pore density and the small and uniform pore diameter. The surface area of the CNTs was controlled and increased by preparing them with uniform diameters. The well-ordered nanoporous alumina templates were fabricated by a two-step anodization method. The cylindrical pore diameter, length, and density of the template utilized for the CNT growth was 53 ± 1 nm, 2 μm, and 3.1×1010 cm−2, respectively. The CNTs with uniform diameter of 44 ± 2 nm were grown on the porous alumina template as electrode materials for the electric double-layer capacitor (EDLC). The EDLC characteristic of the CNT electrodes was examined by measuring the capacitances from the cyclic voltammograms. The specific capacitance of the CNT electrodes can be increased to the value of 121 ± 5 F/g.
Optical Properties of Nanostructured Mesoporous Semiconductor Films
Authors: Nandhakumar Iris , Gabriel Timothy , Li Xiahong , Attard George S. , Markham Matthew , Smith David C. , Baumberg Jeremy J.
Published: September 2012

Direct liquid crystal templating from non-ionic polyoxyethylene surfactants has been utilised to produce well-defined birefringent films of nanostructured cadmium telluride with mesoporous architectures of extended spatial periodicities. The template mixtures and films were characterised by X-ray diffraction, transmission electron microscopy and polarising optical microscopy to ascertain the presence of a regular nanostructure. UV-VIS reflectance spectroscopy was employed to investigate the films' optical properties.
Conductivity dependence on oxygen partial pressure and transport number measurements of La2Mo2O9
Authors: Tarancón A. , Dezanneau G. , Morata A. , Peiró F. , Morante J.R. , Norby T.
Published: September 2012

Transport number measurements and impedance spectroscopy in controlled temperature and atmosphere were used to investigate the electrical properties of La2Mo2O9 sintered samples. These samples were prepared from nanocrystalline La2Mo2O9 powders as obtained from a new soft chemistry route involving the polymerisation of acrylamide. By means of the electromotive force method measurements, the sintered compound was found mainly oxygen conductor in the range of 400 °C-800 °C with oxide-ion transport number greater than 0.99. The effect of the oxygen partial pressure on the electrical conductivity of La2Mo2O9 was investigated by impedance spectroscopy from 1 to 10−22 atm, showing a highly stable conduction properties up to 10−17 atm at 800 °C.
Can a Semiochemical-Based Trapping Method Diminish Damage Levels Caused by Rhabdoscelus obscurus (Coleoptera: Curculionidae)?
Authors: Reddy GVP , Shi P , Mann C R , Mantanona DMH , Dong Z
Published: September 2012

The New Guinea sugarcane weevil, Rhabdoscelus obscurus (Boisduval) (Coleoptera: Curculionidae), is an important pest of palms, ornamental nurseries, and sugarcane in the Pacific Islands. Without effective control methods, R. obscurus populations can cause major or complete loss of palm production in Guam and other Micronesian Islands. Moreover, R. obscurus has inflicted severe attacks on coconut trees on Guam. The role of monitoring is important in judging the dynamics of R. obscurus and recording area wide population trends. There is no precise research information available on the trap catch threshold levels relative to the damage caused by R. obscurus. Here we investigated the assessment of trap catch threshold levels and the potential for predicting R. obscurus larval damage by using adult pheromone trap captures. Spatial patterns of capture were studied in relation to subsequent larval damaged betel nut plants at various locations in Guam, United States, during 2010–2012. The generalized additive model was used to describe the effects of the treatment level (traps/ha), ranging from 0 to 12, and time on reducing the damage of R. obscurus to palms. We find that these two predictors are statistically significant, and the treatment level is demonstrated to be the crucial predictor for reducing the damage. There is no significant difference in effectively controlling the damage between the treatment levels of 9 and 12 traps/ha. At least 9 traps/ha is suggested for effectively controlling the damage based on results from the current study.
FUNCTIONAL ANALYSIS AND TREATMENT OF ARRANGING AND ORDERING BY INDIVIDUALS WITH AN AUTISM SPECTRUM DISORDER
Authors: Rodriguez Nicole M. , Thompson Rachel H. , Schlichenmeyer Kevin , Stocco Corey S.
Published: September 2012

Of the diagnostic features of autism, relatively little research has been devoted to restricted and repetitive behavior, particularly topographically complex forms of restricted and repetitive behavior such as rigidity in routines or compulsive‐like behavior (e.g., arranging objects in patterns or rows). Like vocal or motor stereotypy, topographically complex forms of restricted and repetitive behavior may be associated with negative outcomes such as interference with skill acquisition, negative social consequences, and severe problem behavior associated with interruption of restricted and repetitive behavior. In the present study, we extended functional analysis methodology to the assessment and treatment of arranging and ordering for 3 individuals with an autism spectrum disorder. For all 3 participants, arranging and ordering was found to be maintained by automatic reinforcement, and treatments based on function reduced arranging and ordering.
AN EVALUATION OF STRENGTHENING PRECURSORS TO INCREASE PRESCHOOLER COMPLIANCE
Authors: Kraus Aaron J. , Hanley Gregory P. , Cesana Lori L. , Eisenberg Danielle , Jarvie Adam C.
Published: September 2012

We evaluated the strategy of increasing precursors to compliance on the compliance of 2 preschool boys. Modeling and differential reinforcement were used to increase specific responses to his name being called prior to the opportunity to comply with an instruction. The precursors were stopping the ongoing activity and orienting to, making eye contact with, and saying “yes” to the instructor. High levels of precursors occurred during treatment, and increases in compliance also were observed, even though the consequences for compliance and noncompliance did not change.
DISRUPTIVE EFFECTS OF CONTINGENT FOOD ON HIGH‐PROBABILITY BEHAVIOR
Authors: Frank‐Crawford Michelle A. , Borrero John C. , Nguyen Linda , Leon‐Enriquez Yanerys , Carreau‐Webster Abbey B. , Deleon Iser G.
Published: September 2012

The delivery of food contingent on 10 s of consecutive toy engagement resulted in a decrease in engagement and a corresponding increase in other responses that had been previously reinforced with food. Similar effects were not observed when tokens exchangeable for the same food were delivered, suggesting that engagement was disrupted by the contingent provision of the food, which may have functioned as a discriminative stimulus that occasioned competing responses.
EXAMINING THE UTILITY OF THE STIMULUS PAIRING OBSERVATION PROCEDURE WITH PRESCHOOL CHILDREN LEARNING A SECOND LANGUAGE
Authors: Rosales Rocio , Rehfeldt Ruth Anne , Huffman Nancy
Published: September 2012

We evaluated the effectiveness of a stimulus pairing observation procedure to facilitate tact and listener relations in preschool children learning a second language. This procedure resulted in the establishment of most listener relations as well as some tact relations. Multiple‐exemplar training resulted in the establishment of most of the remaining relations. The implications for the use of these procedures to establish simple vocabulary skills in children are discussed.
EFFECTS OF THREE TYPES OF NONCONTINGENT AUDITORY STIMULATION ON VOCAL STEREOTYPY IN CHILDREN WITH AUTISM
Authors: Saylor Sharyn , Sidener Tina M. , Reeve Sharon A. , Fetherston Anne , Progar Patrick R.
Published: September 2012

We evaluated the effects of 3 types of noncontingent auditory stimulation (music, white noise, recordings of vocal stereotypy) on 2 children with autism who engaged in high rates of vocal stereotypy. For both participants, the music condition was the most effective in decreasing vocal stereotypy to near‐zero levels, resulted in the highest parent social validity ratings, and was selected as most preferred in treatment preference evaluations.
THE EFFECTS OF EXERGAMING ON PHYSICAL ACTIVITY IN A THIRD‐GRADE PHYSICAL EDUCATION CLASS
Authors: Shayne Rachel K. , Fogel Victoria A. , Miltenberger Raymond G. , Koehler Shannon
Published: September 2012

We compared the effects of exergaming and traditional physical education on physical activity among 4 active children who were not overweight and who had experience with the exergaming activities prior to the study. Results showed that exergaming produced substantially higher percentages of physical activity and opportunity to engage in physical activity. In addition, an evaluation of the exergaming equipment showed that exergaming stations were associated with differential levels of physical activity across participants.
ACQUISITION OF SOCIAL REFERENCING VIA DISCRIMINATION TRAINING IN INFANTS
Authors: Pelaez Martha , Virues‐Ortega Javier , Gewirtz Jacob L.
Published: September 2012

This experiment investigated social referencing as a form of discriminative learning in which maternal facial expressions signaled the consequences of the infant's behavior in an ambiguous context. Eleven 4‐ and 5‐month‐old infants and their mothers participated in a discrimination‐training procedure using an ABAB design. Different consequences followed infants' reaching toward an unfamiliar object depending on the particular maternal facial expression. During the training phases, a joyful facial expression signaled positive reinforcement for the infant reaching for an ambiguous object, whereas a fearful expression signaled aversive stimulation for the same response. Baseline and extinction conditions were implemented as controls. Mothers' expressions acquired control over infants' approach behavior for all participants. All participants ceased to show discriminated responding during the extinction phase. The results suggest that 4‐ and 5‐month‐old infants can learn social referencing via discrimination training.
COMPARING THE EFFECTS OF DIFFERENTIAL REINFORCEMENT OF OTHER BEHAVIOR AND RESPONSE‐COST CONTINGENCIES ON TICS IN YOUTH WITH TOURETTE SYNDROME
Authors: Capriotti Matthew R. , Brandt Bryan C. , Ricketts Emily J. , Espil Flint M. , Woods Douglas W.
Published: September 2012

Tics are rapid, repetitive, stereotyped movements or vocalizations that arise from neurobiological dysfunction and are influenced by environmental factors. Although persons with tic disorders often experience aversive social reactions in response to tics, little is known about the behavioral effects of such consequences. Along several dimensions, the present study compared the effects of two treatments on tics: response cost (RC) and differential reinforcement of other behavior (DRO). Four children with Tourette syndrome were exposed to free‐to‐tic baseline, DRO, RC, and quasibaseline rebound evaluation conditions using an alternating treatments design. Both DRO and RC produced substantial decreases in tics from baseline levels. No differential effects of DRO and RC contingencies were seen on self‐reported stress or in the strength of the reflexive motivating operation (i.e., premonitory urge) believed to trigger tics, and neither condition produced tic‐rebound effects. Implications of these findings and directions for future research are discussed.
FURTHER ANALYSIS OF VARIABLES THAT AFFECT SELF‐CONTROL WITH AVERSIVE EVENTS
Authors: Perrin Christopher J. , Neef Nancy A.
Published: September 2012

The purpose of this study was to examine variables that affect self‐control in the context of academic task completion by elementary school children with autism. In the baseline assessment of Study 1, mathematics problem completion was shown to be an aversive event, and sensitivity to task magnitude, task difficulty, and delay to task completion were measured. The effects of manipulating values of those parameters on self‐control then were assessed. For all participants, self‐control increased as a function of one or more changes in task parameter values. In Study 2, the effects of a commitment response on self‐control was assessed. Results indicated that for all participants, levels of self‐control were higher when the opportunity to commit to the immediate aversive event was available.
GENERALIZED INSTRUCTION FOLLOWING WITH PICTORIAL PROMPTS
Authors: Phillips Cara L. , Vollmer Timothy R.
Published: September 2012

The benefits of permanent pictorial prompts in enhancing maintenance and generalization are likely dependent on their degree of stimulus control and the extent to which their use is generalized. Although several studies on the use of pictorial prompts have demonstrated their efficacy (e.g., Pierce & Schreibman, 1994; Wacker & Berg, 1983; Wacker, Berg, Berrie, & Swatta, 1985), there is still some question regarding what ultimately controlled responding. The present study allowed an explicit examination of stimulus control by pictorial prompts. Three 4‐year‐old children with developmental disabilities were taught to complete 4 instructional sets (5 steps each) using pictorial prompts such that the prompts would control responding. All 3 participants showed generalization to the final set after training with 3 sets. These results suggest that training a single task sequence may not be sufficient for acquisition of generalized pictorial instruction following. However, establishing stimulus control by the pictorial prompts rather than teaching behavioral chains may facilitate acquisition of a generalized repertoire.
THE EFFECT OF OUTDOOR ACTIVITY CONTEXT ON PHYSICAL ACTIVITY IN PRESCHOOL CHILDREN
Authors: Hustyi Kristin M. , Normand Matthew P. , Larson Tracy A. , Morley Allison J.
Published: September 2012

The purpose of the current study was to develop and test a method for assessing the effect of outdoor activity context on level of physical activity in preschool children. The Observational System for Recording Physical Activity in Children was used to define the test conditions and various levels of physical activity within a multielement design. In general, all participants were fairly sedentary during the analysis. The fixed playground equipment condition produced the most moderate‐to‐vigorous physical activity, a finding that does not correspond to the descriptive assessment literature on childhood physical activity.
DIFFERENTIAL EFFECTS OF SEATING ARRANGEMENTS ON DISRUPTIVE BEHAVIOR OF FIFTH GRADE STUDENTS DURING INDEPENDENT SEATWORK
Authors: Bicard David F. , Ervin Angela , Bicard Sara C. , Baylot‐Casey Laura
Published: September 2012

We investigated teacher versus student seat selection in the context of group and individual seating arrangements. Disruptive behavior during group seating occurred at twice the rate when students chose their seats than when the teacher chose. During individual seating, disruptive behavior occurred more than three times as often when the students chose their seats. The results are discussed in relation to choice and the matching law.
PRELIMINARY INVESTIGATION OF A VIDEO‐BASED STIMULUS PREFERENCE ASSESSMENT
Authors: Snyder Katie , Higbee Thomas S. , Dayton Elizabeth
Published: September 2012

Video clips may be an effective format for presenting complex stimuli in preference assessments. In this preliminary study, we evaluated the correspondence between preference hierarchies generated from preference assessments that included either toys or videos of the toys. The top‐ranked item corresponded in both assessments for 5 of the 6 participants, and the top‐ and bottom‐ranked items corresponded for 4 participants. The implications of these results for future research on video preference assessments are discussed.
USING A TAPED INTERVENTION TO IMPROVE KINDERGARTEN STUDENTS' NUMBER IDENTIFICATION
Authors: Krohn Katherine R. , Skinner Christopher H. , Fuller Emily J. , Greear Corrine
Published: September 2012

A multiple baseline design across students was used to evaluate the effects of a taped numbers (TN) intervention on the number‐identification accuracy of 4 kindergarten students. During TN, students attempted to name the numbers 0 through 9 on randomized lists before each number was provided via a tape player 2 s later. All 4 students showed immediate increases and reached 100% in number‐identification accuracy. One student reached 100% accuracy after TN was supplemented with performance feedback, reinforcement, and overcorrection.
IMPACT OF TREATMENT INTEGRITY ON INTERVENTION EFFECTIVENESS
Authors: Fryling Mitch J. , Wallace Michele D. , Yassine Jordan N.
Published: September 2012

Treatment integrity has cogent implications for intervention effectiveness. Understanding these implications is an important, but often neglected, undertaking in behavior analysis. This paper reviews current research on treatment integrity in applied behavior analysis. Specifically, we review research evaluating the relation between integrity failures and the efficacy of behavioral interventions. Avenues for future research are provided.
ANALYSIS OF SELF‐RECORDING IN SELF‐MANAGEMENT INTERVENTIONS FOR STEREOTYPY
Authors: Fritz Jennifer N. , Iwata Brian A. , Rolider Natalie U. , Camp Erin M. , Neidert Pamela L.
Published: September 2012

Most treatments for stereotypy involve arrangements of antecedent or consequent events that are imposed entirely by a therapist. By contrast, results of some studies suggest that self‐recording, a common component of self‐management interventions, might be an effective and efficient way to reduce stereotypy. Because the procedure typically has included instructions to refrain from stereotypy, self‐recording of the absence of stereotypy, and differential reinforcement of accurate recording, it is unclear which element or combination of elements produces reductions in stereotypy. We conducted a component analysis of a self‐management intervention and observed that decreases in stereotypy might be attributable to instructional control or to differential reinforcement, but that self‐recording per se had little effect on stereotypy.
Assessment of mental health in adults of the northern part of the city of Kosovska Mitrovica
Authors: Mirkovic Momcilo , Simic Snezana , Trajkovic Goran
Published: September 2012

Background/Aim. Mental health disorders lead to disorder of effective
functioning of people and deterioration of quality of life. Early detection
of individuals at risk of mental health disorders is extremely important from
the aspect of mental health disorders prevention. The aim of the research was
to determine the frequency of mental health problems among adult residents of
northern Kosovska Mitrovica and to examine the association between frequency
of mental health problems and socio-demographic and other characteristics of
the population obtained by the questionnaire. Methods. The cross-sectional
study on the representative sample of adult residents of northern Kosovska
Mitrovica was performed in October 2009. To obtain information about the
characteristics of mental health the Goldberg?s General Health Questionnaire
(GHQ-28) was used. For performing survey at site the method of rapid
epidemiological assessment was chosen. Statistical analysis included the
methods of descriptive statistics, multivariate regression analysis and
calculation of the Cronbach?s alpha coefficient of internal consistency of
the questionnaire. Results. Mental health problems (total score) were present
in almost half of the respondents (49.2%). Psychosomatic problems were
present in more than half of the respondents (55.4%), while anxiety and
insomnia were present in almost half of the respondents (49.2%). Social
dysfunction had more than three fifths of the respondents (63.1%) and
depression more than a quarter of the respondents (28.5%). More positive
responses in the questionnaire were statistically significantly associated
with older age, poor financial situation, abuse and assessing of the current
political-security situation as high risk. The value of Cronbach?s alpha
coefficient was 0.705. Conclusions. Almost half of the respondents (49.2%) of
North Kosovska Mitrovica had mental health problems. Mental health problems
were associated with older age, poor financial situation, abuse and
considering the current political security situation as high-risk factor.
The importance of timely ophthalmologic examination in preterm infants at risk of retinopathy occurrence
Authors: Knezevic Sanja , Stojanovic Nadezda , Oros Ana , Knezevic Jasmina
Published: September 2012

Background/Aim. Retinopathy of prematurity (ROP) is a multifactorial disease
in premature infants. The aim of this study was to determine the incidence of
ROP in children treated at the Center of Neonatology, Pediatric Clinic,
Clinical Center in Kragujevac, Serbia. Methods. The study covered all
children with birth weight below 2,000 g and/or gestational age below the
37th week, who from June 2006 to December 2009 underwent ophthalmological
examination for ROP. The results of fundoscopy were classified in accordance
with the International Classification of ROP. The treatment of infants and
those with ROP was conducted in accordance with the early treatment of ROP
study recommendations. We analyzed gestational age, birth weight and
postconceptional age in two groups: healthy infants and those with severe
form of ROP. Statistical analysis was performed using the SPSS 16. Results. A
total of 478 children met the criteria of screening for ROP. Severe stage of
ROP, which required laser treatment, had 102 (21.3%) children. Out of the
infants with severe ROP 14 (13.7%) of the infants with APD had aggressive
posterior disease, while two (0.4%) remained blind. The differences in the
mean values of gestational age between the healthy and the children with
severe form of the disease were statistically significant (p < 0.0005). The
mean value of gestational age for the healthy children was 33.33 ? 2.28 weeks
and for the seek infants 30.66 ? 2.79 weeks. The mean value of the weight in
healthy children was 1.981 ? 407 g, and in sick children 1.535 ? 434 g which
was statistically significant (p < 0.0005). Multivariate binary logistic
regression showed that the occurrence of the disease depends on body weight
and gestational age. Conclusion. The incidence of severe forms of ROP was
21.3%. Aggressive form of ROP was present in 13.7% of the children. The
cut-off value for body weight was 1.740 g, and for gestational age 32.5 weeks.
Incarcerated inguinal hernias surgical treatment specifics in elderly patients
Authors: Pesic Ivan , Karanikolic Aleksandar , Djordjevic Nebojsa , Stojanovic Miroslav , Stanojevic Goran , Radojkovic Milan , Nestorovic Milica
Published: September 2012

Background/Aim. Incarcerated inguinal hernias surgical treatment represents
one of the most frequent surgical treatments in elderly patients. The
percentage of incarcerated inguinal hernias urgent surgical treatments is
growing exponentially with the age in patients over 50. The aim of the study
was to investigate some of the factors that may have impact on the
incarcerated inguinal hernias surgical treatment outcome in elderly patients.
Methods. The study included 180 patients classified in two groups: the study
group (> 65 years of age) and the control group (? 65), managed in the
period from January 2005 till March 2009 at the General Surgery Clinic,
Clinical Center Nis. Results. Most of the patients had right inguinal hernia
(52.6%, the study group; 59.1%, the control group). All the study group
patients suffered from some of accompanying chronic diseases (100%), opposite
to 39 (59%) patients of the control group. Synthetic material was implanted
in 124 (68.9%) patients, while the tension technique was performed in 65
(31.1%) patients. The duration of incarceration more than 24 h (p = 0.015),
previous abdominal surgery (p = 0.001), the American Society of
Anesthesiologists physical status classification system (ASA classification)
(p = 0.033) and the presence of chronic diseases (p = 0.01) appeared to be
statistically significant risk factors for performing intestinal resection in
the study group, while in the control group they represented risk factors,
but not at the level of statistical significance (p <0.05), except for the
duration of incarceration (p = 0.007). A higher ASA stage (p = 0.001) and the
presence of bowel resection (p <0.001) are the most important risk factors
for lethal outcome in both groups of patients. Conclusion. Incarcerated
inguinal hernia in elderly patients is a serious problem. A higher ASA score
and the presence of bowel resection are the most important factors related to
unfavorable outcome.
Congenital upper eyelid coloboma with ipsilateral eyebrow hypoplasia
Authors: Vulovic Dejan , Novakovic Marijan , Sarenac Tatjana , Janicijevic-Petrovic Mirjana , Petrovic Nenad , Sreckovic Suncica , Milicevic Sasa , Piscevic Branislav
Published: September 2012

Introduction. Coloboma is a Greek word, which describes the defect of all
layers of the organ, and it can be congenital or as the result of an injury,
operation, or some disease. Congenital upper eyelid coloboma is a rare
anomaly, with the unknown incidence. The size of the defect is different, but
it always involves all layers of the eyelid. This malformation is more
frequent at the upper eyelid, and unilaterally, at the junction of the medial
two thirds. Sometimes, it can also involve the eye, and may be a component of
many syndromes (Goldenhar, Fraser, Manitoba, CHARGE, Cat eye). Case report.
We are describing the case of the upper eyelid coloboma with the rare eyebrow
anomaly at the three-month old girl, and the result of reconstruction. The
baby was treated conservatively with lubricants and overnight patching.
Pentagonal excision of the defect was performed in general anesthesia. Three
layers of the eyelid were prepared: the skin, muscle and tarsoconjunctival
layer. Because of orbicularis muscle malposition, reinsertion and reposition
of the muscle fibres were performed. Then, lateral canthotomy was made and
the suture of three layers of the eyelid. Catgut suture 7-0 was used for the
conjunctiva and muscle. Nylon 6-0 was used for skin suture. Z-plasty was done
on the upper part of the pentagonal excision in order to reduce skin tension
at the suture line. The operation lasted about 60 minutes and the
hospitalization three days. The occlusive dressing was applied for two days.
The stitches were removed after seven days. The postoperative swelling of the
upper and lower eyelid disappeared in five days. There were no complications
in the postoperative period. Conclusion. The main principle of the treatment
of eyelid coloboma is surgical reconstruction of all layers of the eyelid, in
optimal period, using different surgical methods, which depends on the size
of the defect. An early diagnosis is of the greatest importance, as well as
the treatment of associated anomalies. Complications of the upper eyelid
coloboma depend on the size of the defect, presence of the eye anomalies and
the method of reconstruction.

 This article has been corrected. Link to the correction 10.2298/VSP1611078E
Use of a spiral rectal diaphragm technique to control anal sphincter incontinence in a cat
Authors: Pavletic Michael , Mahn Matt , Duddy Jean
Published: September 2012

Case Description—A 10-year-old castrated male domestic shorthair cat was examined for a mass involving the right anal sac region.

Clinical Findings—The mass was diagnosed as a fibrosarcoma, and resulted in progressive tenesmus, requiring repeated resection.

Treatment and Outcome—Surgical removal of the fibrosarcoma was performed on 4 occasions, including complete resection of the anal sphincter muscles and portions of the rectum. A perineal urethrostomy was required during the third surgical procedure secondary to tumor invasion of the preputial tissues. To reduce involuntary loss of feces, the remaining rectal wall was rotated approximately 225° prior to surgical closure during the second, third, and fourth surgical procedures. This procedure created a natural spiral diaphragm within the rectal lumen. The elastic spiral barrier reduced inadvertent fecal loss and facilitated fecal distention of the terminal portion of the colon, allowing the patient to anticipate the impending passage of feces and to use the litter tray on a daily basis.

Clinical Relevance—With complete loss of the terminal portion of the rectum and anal sphincter muscles, spiraling the rectum created a deformable threshold barrier to reduce excessive loss of stool secondary to fecal incontinence. On the basis of the positive outcome in this patient, this novel technique may be a useful option to consider for the treatment of cats with loss of anal sphincter function.
A fuzzy logic approach to modeling a vehicle crash test
Authors: Pawlus Witold , Karimi Hamid , Robbersmyr Kjell
Published: September 2012

This paper presents an application of fuzzy approach to vehicle crash modeling. A typical vehicle to pole collision is described and kinematics of a car involved in this type of crash event is thoroughly characterized. The basics of fuzzy set theory and modeling principles based on fuzzy logic approach are presented. In particular, exceptional attention is paid to explain the methodology of creation of a fuzzy model of a vehicle collision. Furthermore, the simulation results are presented and compared to the original vehicle’s kinematics. It is concluded which factors have influence on the accuracy of the fuzzy model’s output and how they can be adjusted to improve the model’s fidelity.
Changing pattern of Peripheral Vascular disease in Asian countries
Authors: Khan M I
Published: September 2012

Not available DOI: http://dx.doi.org/10.3329/bjms.v11i3.11713 Bangladesh Journal of Medical Science Vol. 11 No. 03 July12
The Declining Science And Art Of Clinical Examination- An Introspect
Authors: Utpal D , Sayak R , Amitesh A , De K K
Published: September 2012

Not available DOI: http://dx.doi.org/10.3329/bjms.v11i3.11715 Bangladesh Journal of Medical Science Vol. 11 No. 03 July12
Mortality In Thalassemic Patients From Solapur District, Maharashtra State, India
Authors: Nikam S V , Dama S B , Chondekar RP , Dama L B , Jawale C S
Published: September 2012

Objective: The aim of the present study is to surveying the mortality in thalassemic patients from Solapur   District, Maharashtra State, India. Methods: Present observational survey study, one hundred twenty five   clinically proved by their medical reports, cases of thalassemic children's with age 6 months to 18 Years,   coming for to get blood transfusion from different parts of Solapur district. Results: The results indicates   that the increased mortality during 11-15 years of age. As a result, transfusional iron overload can cause   increased morbidity and premature mortality in thalassemia patients. This study will be helpful in further   defining the morbidity and mortality in thalassemic patients. DOI: http://dx.doi.org/10.3329/bjms.v11i3.11717 Bangladesh Journal of Medical Science Vol. 11 No. 03 July12