bluuebunny/crossref_metadata_2025 huggingface dataset:
Training in Behavioural Psychotherapy
Authors: Marks Isaac
Published: June 2009

An important aim of the B.A.B.P. is to stimulate training programmes among the disciplines from whose ranks it draws its members. At least three big issues affect the kinds of training programmes which may be desirable. The first is the clinical setting in which the behavioural psychotherapy is to be practised, e.g. is the work going to be primarily with subnormal children, or with adult neurotics? While there are certain common therapeutic principles which can be generalised across most settings, skilled behavioural psychotherapy also requires detailed and expert knowledge of the particular clinical problems concerned. Those who have worked with adult neurotics may know very little about subnormals, and vice versa: A practitioner thus requires good experience of the clinical area involved. Recognition of the fact that different areas need differential training is attested by the separate trainings which the nursing and psychiatric professions offer for subnormality and for general psychiatry.
Potential Roles for Social Workers in Behavioural Psychotherapy
Authors: Hudson Barbara
Published: June 2009

In order to deliver a service you have got to have customers. You have got to have permission to provide the service, and you have got to have the competence to provide the service. I want to suggest that social workers do have the clients, are gradually getting the permission, and are suitable candidates for further training in order to become competent.
Some issues in Smoking Modification Research
Authors: Raw Martin
Published: June 2009

Behavioural psychotherapists have contributed an enormous amount of research to the problem of smoking; The attraction of smoking as a research field is fairly easy to see. Smokers constitute a high proportion of the adult population of most industrialised countries. A large, reasonably homogeneous subject pool is therefore readily available for research, and since so many smokers claim a desire to stop smoking (McKennell and Thomas 1967), they are ideal for clinical research. In addition the behaviour itself is easy to measure and it is fairly easy to demonstrate behaviour change as a result of therapeutic intervention. Smoking lends itself readily to analysis using the concepts of behavioural psychology, and because such large populations of smokers are always available for therapeutic research, the application of traditional experimental methodology (based upon controlled group comparisons with random allocation of subjects to groups) is quite easy. Despite these apparently favourable conditions, relatively little progress has been made in terms of therapeutic success rates (Bernstein 1969, Bernstein and McAlister 1975). The purpose of this paper is to suggest some reasons for this, and to suggest that behavioural psychotherapists still have a very important role to play in the smoking withdrawal field.
How Do Patients Perceive Behavioural Psychotherapy?
Authors: Shepherd Geoff
Published: June 2009

How patients perceive behavioural psychotherapy and what they consider to be the important components and processes involved remain largely a matter for speculation and clinical impression. This is unfortunate since subjective reports constitute a unique source of information and their investigation might yield some valuable insights into the therapeutic process. For example, it could help clarify the role of ‘non-specific’ factors in treatment (Gelder et al., 1973), it might also shed some light on the importance of attributions in behaviour change (Davison and Valins, 1969). With these considerations in mind we decided to ask a group of patients who had improved following a course of behavioural psychotherapy a few simple questions about why they thought this change had occurred.
Assessment Measures in Obsessional Illness
Authors: Philpott Robin
Published: June 2009

Some difficulties in measuring obsessional illness are described. Measurement techniques used in previous behavioural or drug treatment trials are reviewed.
The Medical Student as Behavioural Psychotherapist
Authors: Stern R. S.
Published: June 2009

A group of medical students were randomly selected from a larger group to carry out behaviour therapy under supervision. Ten patients with phobic disorders and two with obsessive-compulsive neurosis were treated, and the results, assessed by ratings of proved reliability, compared favourably with other studies in which psychiatrists or nurses acted as therapists. A questionnaire survey showed that students involved in therapy had a more favourable opinion about this kind of treatment than those receiving only theoretical instruction. The results suggested not only that medical students make good behavioural psychotherapists but also that the subject is a worthwhile training experience which warrants inclusion in the curriculum.
Self-Talk in Depression
Authors: Teasdale John
Published: June 2009

Cognitive behaviour modification incorporates procedures aimed at changing clients feelings and actions by modifying what they say to themselves, or think. It is assumed that such self-statements determine, to some extent, emotion and behaviour. The experiments reported sought to examine this assumption in depression, i.e., to what extent do patients feel depressed because they think depressing thoughts? Beck's cognitive theory of depression suggests disordered thinking is the primary cause of depression.
A note on teaching behaviour modification to social work students
Authors: Jehu Derek
Published: June 2009

In Britain, social workers are trained on a variety of courses in colleges of further education, polytechnics and universities. Some of these courses are intended primarily for non-graduates and last two-years, others are four year undergraduate courses combining a first degree with professional training, and the remainder are at postgraduate level. Students in the last group may have graduated in any discipline from the humanities or the physical, biological or social sciences, many have degrees which included the study of psychology for one, two or three years, and some of these are honours graduates in this subject. The postgraduate social work courses last one or two years depending on the subjects covered in the students' first degrees.
Evidence to the D.H.S.S. Committee of Enquiry into Mental Handicap Nursing and Care
Authors: Cullen Chris , Lomas Howard , Tennant Laurence
Published: June 2009

The British Association for Behavioural Psychotherapy (BABP) is not competent to answer fully every question asked by the D.H.S.S. Committee of Enquiry, and it has consequently restricted its evidence to those areas where behavioural psychotherapy has obvious and relevant contributions to make.
B. A. B. P. Annual Conference July, 1976 - Abstracts of Papers: A Home-Treatment Programme for Agoraphobia
Authors: Mathews Andrew
Published: June 2009

Examination of the results of previous treatment trials suggests that although behavioural treatment is effective in reducing agoraphobic symptoms, a large amount of treatment time is required, and patients tend to make no further gains when regular therapy sessions stop. A treatment programme was developed which was designed to provide an on-going alternative within the patient's own environment for the instructions and support normally given by the therapist, with the intention of reducing therapist time requirements and maintaining progress in the absence of contact during follow-up. This was done by incorporating the following features: detailed but easily understood instructions were given in written form as well as in discussion, all practice was carried out from the patients' own home, the patients spouse was actively involved in planning and encouraging practice attempts, and both patient and spouse were asked to take overall responsibility for running the programme themselves. Instructions were given in the form of manuals which contained material covering the nature of agoraphobic symptoms, the selection of targets, graded practice and suggestions for panic management.
Imaginal Rehearsal with Dental Phobics
Authors: Rezin V. A. , Matthews A. M.
Published: June 2009

Previous research suggests that the main causes of dental fear are a traumatic dental experience and negative expectations from others (Lautch, 1971), (Kleinknacht, 1973).
The Token Economy Package: Social v. Token Reinforcement
Authors: Elliott P. A. , Barwell F. , Hooper A. , Kingerlee P. E.
Published: June 2009

The paper reports a Token Economy project involving 18 long stay male patients (diagnosis chronic schozophrenia), average length of hospitalisation twenty-five years. The project comprised a one month baseline period, a six month Token Economy phase, a two month experimental phase and a second three months Token Economy. Conditions were the same for all patients except during the experimental phase where they were randomly assigned to one of three experimental groups to investigate the relative importance of social reinforcement and other variables involved in token systems. The groups were (1) a social reinforcement only group; (2) a social reinforcement and non-contingent tokens; (3) a social reinforcement and contingent, non-spendable tokens. Each groups' performance was compared both with the other groups and with their own performance over all phases of the study. Assessment measures comprised standardised psychiatric rating scales - the Nurses Observation Scale for In-patient Evaluation (Honigfeld and Klett, 1965; Honigfeld et al 1966), and the Psychotic Reaction Profile (Lorr et al, 1960); other rating checklists, and time-sampling data. Analysis of Variance was carried out on all data over the four phases of the programme. The total token economy package as represented by the first token economy period was shown to be effective in promoting improvements in most areas of patients' functioning as compared to baseline. Results during the experimental phase suggest that contrary to our initial hypothesis social factors involved in exchanging tokens are not demonstrably important sources of reinforcement in Token Economies. There were no inter-group differences during the experimental phase, suggesting that none of the variables studied were critical factors. After the experimental phase the return to the complete token package produced an unclear picture where there were significant improvements on some scales, but significant declines on others.
A Comparison of three Behaviour Therapies in the Treatment of Social Phobia
Authors: Shaw P.
Published: June 2009

No previous trial has been reported in which only patients with social phobia were treated. There were nine such patients in a previous trial involving 18 agoraphobics and 18 other phobics (Gelder et al, 1973), in which they responded poorly to desensitization but no conclusion could be drawn from such a small sample. Gordon Paul (1966) found that volunteers with public speaking anxiety, a limited manifestation of social phobia, responded better to desensitization than to psychotherapy. Donald Meichenbaum (1971) also showed that similar volunteers responded well to desensitization but when social anxiety was more general subjects did better with a psychotherapy involving modification of self-instructions. It seemed clear that desensitization in the treatment of patients with social anxiety required further investigation and in the present trial it was compared with imaginal implosion and also with social skills training, an in-vivo treatment.
The Treatment of Social Failure: SST and SD Compared
Authors: Trower Peter
Published: June 2009

The study by Shaw, P.H. et al (This Bulletin) has described the effect of 3 kinds of treatment on one kind of social problem - social phobia. The present study compared the effect of 2 treatments on another kind of social problem - social inadequacy (the two studies were carried out in parallel so that comparisons could be made between them).
Cost-Effectiveness of Nurse Therapists' Behavioural Treatment of Neurotic Disorders
Authors: Marks Isaac , Ginsberg Gary
Published: June 2009

With limited therapeutic resources, increasing demands for behavioural psychotherapy impose rationing by long waiting lists. Every patient taken on for treatment denies it to another who has to wait. Given this constraint, therapists can help many more patients by concentrating their scarce time on sufferers likely to show tangible improvement with brief treatment. This policy was applied to the treatment of 42 neurotics (mainly phobics and obsessive-compulsives) who completed exposure treatment with nurse-therapists in a mean of 9 sessions (16 hours). A cost-effectiveness study was mounted of the year before and after treatment.
The Role of the Betting Shop Environment in the Training of “Compulsive” Gamblers
Authors: Dickerson Mark
Published: June 2009

Entering the betting shop environment may be influenced not only by economic motives (Hess and Diller, 1969) but also by early learning within the family (Bergler, 1957) and by the contingencies operative in the wider social environment (Newman, 1972).
“Self-Control” – the answer to Obesity?
Authors: Elliott Sandra
Published: June 2009

In 1958 Stunkard and McLaren-Hume concluded that “Most obese persons will not remain in treatment, of those that remain in treatment, most will not lose weight, of those that do lose weight, most will regain it.” Since then great advances have been claimed for behavioural, specifically self-control, treatments of obesity, (i.e. Stunkard, 1972). This had been witnessed in a great proliferation of research papers on group studies purporting to demonstrate the superiority of this approach and to verify its theoretical basis.
The teacher-Child interaction Project
Authors: Yule William , Berger Michael , Wigley Veronica
Published: June 2009

Since 1969, there has been a slow, but steady, increase in the number of studies which have attempted to apply behavioural methods within the British school setting. The variety of papers reported in this volume attest to the wide level of current interest. Many reviewers of American experience (e.g. Sherman and Bushell, 1975;O'Leary and O'Leary, 1972) show that both academic and classroom behaviours have been investigated, and there is a general agreement that the aim of behavioural intervention is not necessarily to make children “be still, be quiet and be good” (Winnett and Winkler, 1972). Rather, the aim is to help the classroom teacher to use the ongoing teacher-child interaction in a deliberate, positive way so as to foster the optimum level of personal development and academic attainment in her pupils. This paper draws on our experiences of the past four years of training groups of teachers in behavioural management, and concentrates on some of the important issues involved in ensuring that behavioural intervention of the highest quality can be offered to teachers in schools.
A Technology for Contingency Management of Disruptive Behaviour by the Classroom Teacher
Authors: Appleton C.
Published: June 2009

Early studies of the application of behaviour modification techniques in both special and normal classroom settings indicated that teachers could incorporate the more systematic management procedures without highly specialised training (Clazarioand Yelon, 1967: Becker, Madsen, et al., 1967). However, some of the earliest studies were closer to the laboratory than the real-life classroom setting in that they required elaborate recording procedures and used material reinforcers which are often unacceptable to teachers. Reversal designs, commonly used in early studies, proved impractical in wider settings. Problems such as these led the present author to place greater emphasis on extinguishing appropriate behaviours, using natural reinforcers identified by the Premack principle, using simplified recording procedures and using multiple baseline design.
The Vanishing Problem
Authors: Harrop Alex
Published: June 2009

The applications of behaviour modification techniques in schools have undergone many changes in recent years. The original model of one or two disruptive pupils in a class being treated by the teacher, whilst independent observers recorded the changes in behaviour, has been considerably widened. The kinds of behaviour selected for treatment, the number of pupils involved, the types of contingencies managed, and the methods of recording have all become diversified; and this diversification has been facilitated by the emergence of more complex designs, which complement the original design of BASELINE, TREATMENT and REVERSAL.
Results and impressions of Using Behaviour Modification in a School's Psychological Service - A Personal View
Authors: McNamara E.
Published: June 2009

In England over the last ten years Behaviour Modification has become increasingly more known, accepted and utilised in the education sector; but only in the last half decade or so has Behaviour Modification been utilised with any generality and regularity.
Application of Behavioural Analysis and Behaviour Modification in School Psychological Service Practice
Authors: Galloway David
Published: June 2009

Behaviour modification in education has come a long way since the early 1960's when workers such as Zimmerman and Zimmerman (1962) and Ferster (1967) took learning theory out of the animal laboratory and into the classroom. Today the problem is not to locate books, articles and pamphlets on behaviour modification but to select the most useful material from an extensive and expanding range. This has not been achieved without a backlash no less vitriolic for not always being well informed (Burden, 1976; Quicke 1976). Nevertheless, some of the criticisms should be taken seriously. Graham (1974) has complained of the rigidity of some behaviour modifiers, and the hargon-laden style of many articles is admirably calculated to deter teachers and parents (not to mention psychologists and psychiatrists); it is only quite recently, for example, that a majority of authors have discovered that calling children by their names–instead of “S”—is not inconsistent with clarity or accuracy.
Aspects of the Use of Behaviour Modification in Secondary Schools
Authors: Lane David A.
Published: June 2009

The Hungerford Centre has for three years been providing a support service to schools based solely on the application of experimentally validated treatment techniques. (Behaviour modification).
Gilbey House: A Token Economy Management Scheme in a Residential School for Adolescent Boys in Trouble
Authors: Brown Barrie
Published: June 2009

Intervention based on social learning principles is, of course, not new to the treatment of delinquency. A variety of behaviour modification techniques, and in particular token economy schemes have been tried out in the U.S.A. and Canada. Most have been extensively evaluated and found to be far more effective than alternative schemes (Braukmann and Fixsen 1975). Of course, the judicial and welfare context in which Braukmann and Fixsen compare the relative merits of various approaches to delinquency prevention programmes is very different from that operating in the United Kingdom. There are, however, a number of points common to both contexts–there has been very little emphasis on, or funds given to, systematic programme evaluations and those that have been conducted (for example, see reviews by Logan 1972 and Slaikeu 1973) have tended to fall far short of meeting basic research design requirements. Secondly, in both settings perhaps too much emphasis has been placed upon preventing recidivism as a goal of treatment. Braukmann and Fixsen point out that re-conviction as an index of treatment progress does not allow differential qualitative feedback to the adolescent to be closely geared to his progress, and that, in the main, behavioural approaches have tended to fare much better in carrying out scientifically respectable evaluation of their progress in addition to demonstrating a much higher success rate both in terms of recidivism and in terms of more microscopic measures of behavioural improvement. The goal of any behavioural treatment for youngsters in trouble may be simply to extend his choice of behaviour rather than simply prevent recidivism.
Improved diagnostics for NWP verification in the tropics
Authors: Koh Tieh‐Yong , Ng Jun Siang
Published: June 2009

The root‐mean‐square error (RMSE) is often used to verify forecasts. However, its strong dependence on the observation variability makes it unsuitable for comparing model performance between regions where observation variability is much different, e.g., across vertical levels or between the midlatitudes and the tropics. The alpha index based on the tensor variance of forecast‐observation discrepancy was formulated to improve on RMSE (and the closely related bias‐corrected RMSE). An “error ellipse” was used to represent the random error in vector wind, yielding two other diagnostics: eccentricity and orientation. These diagnostics were applied to verify Naval Research Laboratory's limited‐area model, Coupled Ocean/Atmospheric Mesoscale Prediction System (COAMPS), for the first time in Southeast Asia. COAMPS forecasts were verified against radiosonde data from South China Sea Monsoon Experiment (SCSMEX), May–June 1998. Results revealed falling model performance as forecast time increases but little difference between forecasts at 18‐km and 54‐km resolution. Systematic errors in the model dynamics were suggested from the biases. The alpha indices show that (after bias correction) COAMPS performs best for wind, followed by temperature and then by dew point depression. In this tropical region, 1‐day persistence forecasts were only outperformed by the model for wind predictions between 400 mb and 850 mb at forecast times less than 24 hr. The RMSE diagnostic was shown to sometimes yield misleading evaluation of the model's performance. The wind error ellipses revealed that the random error tended to align more with the background flow than with the model bias, possibly indicating a dynamical reason for its existence.
Evaluating uncertainty in integrated environmental models: A review of concepts and tools
Authors: Matott L. Shawn , Babendreier Justin E. , Purucker S. Thomas
Published: June 2009

This paper reviews concepts for evaluating integrated environmental models and discusses a list of relevant software‐based tools. A simplified taxonomy for sources of uncertainty and a glossary of key terms with “standard” definitions are provided in the context of integrated approaches to environmental assessment. These constructs provide a reference point for cataloging 65 different model evaluation tools. Each tool is described briefly (in the auxiliary material) and is categorized for applicability across seven thematic model evaluation methods. Ratings for citation count and software availability are also provided, and a companion Web site containing download links for tool software is introduced. The paper concludes by reviewing strategies for tool interoperability and offers guidance for both practitioners and tool developers.
Three‐dimensional nonlinear evolution of equatorial ionospheric bubbles with gravity wave seeding and tidal wind effects
Authors: Keskinen M. J. , Vadas Sharon L.
Published: June 2009

The three‐dimensional nonlinear evolution of equatorial ionospheric bubbles, using a realistic lower atmospheric gravity wave source, has been computed. It is found that three‐dimensional finite parallel conductivity effects are important and lead to reduced gravity wave‐induced electric fields, less depleted bubbles, and longer time scale bubble evolution compared to the two‐dimensional case. It is concluded that nearly zonal propagating gravity waves are needed to excite equatorial ionospheric bubbles in the presence of zonal tidal winds. The simulated ionospheric bubble structures are consistent with recent observations in the SpreadFEx campaign.
Numerical simulations of texture development and associated rheological anisotropy in regions of complex mantle flow
Authors: Castelnau O. , Blackman D. K. , Becker T. W.
Published: June 2009

The development of Lattice Preferred Orientations (LPO) within olivine aggregates under flow in the upper mantle leads to seismic and rheological (or viscoplastic) anisotropies. We compare predictions from different micromechanical models, applying several commonly used theoretical descriptions to an upwelling flow scenario representing a typical oceanic spreading center. Significant differences are obtained between models in terms of LPO and associated rheology, in particular in regions where the flow direction changes rapidly, with superior predictions for the recently proposed Second‐Order approach. This highlights the limitations of ad hoc formulations. LPO‐induced rheological anisotropy may have a large effect on actual flow patterns with 1–2 orders of magnitude variation in directional viscosities compared to the isotropic case.
Interdecadal variability of tropical cyclone landfall in the Philippines from 1902 to 2005
Authors: Kubota Hisayuki , Chan Johnny C. L.
Published: June 2009

A dataset of tropical cyclone landfall numbers in the Philippines (TLP) is created from a combination of historical observation records of the Monthly Bulletins of Philippine Weather Bureau and Joint Warning Typhoon Center best‐track data for the period of 1902 to 2005. Interdecadal variability of TLP is found to be related to different phases of the El Niño/Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO). The annual TLP has an apparent oscillation of about 32 years before 1939 and an oscillation of about 10–22 years after 1945. No long‐term trend is found. During the low PDO phase, the annual TLP decreases (increases) significantly in El Niño (La Niña) years. During high PDO phase, however, the difference in annual TLP between different ENSO phases becomes unclear. These results suggest that natural variability related to ENSO and PDO phases appears to prevail in the interdecadal variability of TLP.
An energetic‐particle‐mediated termination shock observed by Voyager 2
Authors: Florinski V. , Decker R. B. , le Roux J. A. , Zank G. P.
Published: June 2009

Voyager 2 crossed the solar wind termination shock several times during August 30 – September 1 of 2007. During the last forty days before the crossing intensities of energetic ions measured by the LECP instrument were increasing exponentially, and their spectrum showed clear evidence of unfolding at low energies. Plasma data featured a broad velocity precursor, where solar wind speed decreased from about 380 km/s far upstream to ∼300 km/s at the shock. By using plasma and energetic particle conservation laws we demonstrate that the speed decrease during Voyager 2's last ∼40 days in the solar wind could be plausibly produced by the back‐pressure of energetic ions with energies of a few MeV on the upstream plasma flow. These particles propagate diffusively upstream from the termination shock, producing a shock precursor that has a characteristic lengthscale of 0.35 AU, assuming the shock has not moved substantially during that time.
Assimilation of coastal Doppler radar data with the ARPS 3DVAR and cloud analysis for the prediction of Hurricane Ike (2008)
Authors: Zhao Kun , Xue Ming
Published: June 2009

The impact of radar data on the analysis and prediction of the structure, intensity, and track of landfalling Hurricane Ike (2008), at a cloud‐resolving resolution, is examined. Radial velocity (Vr) and reflectivity (Z) data from coastal radars are assimilated over a 6‐h period before Ike landfall, using the ARPS 3DVAR and cloud analysis package through 30‐min assimilation cycles. Eighteen‐hour predictions were made. All 4 experiments that assimilate radar data produce better structure, intensity and precipitation forecasts than that from operational GFS analysis. The improvement to the track forecast lasts for the entire 18 hours while that to intensity prediction lasts about 12 hours. The Vr data help improve the track forecast more while reflectivity data help improve intensity forecast most. Best results are obtained when both Z and Vr data are assimilated.
Inhibitory effect of glycyrrhizin on the neutrophil‐dependent increase of R5 HIV replication in cultures of macrophages
Authors: Yoshida Tsuyoshi , Kobayashi Makiko , Li Xiao‐Dong , Pollard Richard B , Suzuki Fujio
Published: June 2009

It has been described that polymorphonuclear neutrophils (PMNs) enhance the replication of CC‐chemokine receptor 5/macrophage‐tropic (R5) HIV in cultures of monocyte‐derived macrophages (MDMs). In this study, the inhibitory effect of glycyrrhizin (GL) on R5 HIV replication influenced by PMNs was investigated in MDM cultures. The replication of R5 HIV in MDMs was greatly enhanced when cells were co‐cultured with freshly isolated PMNs (syngeneic to MDMs). When GL was added to this culture, however, the viral replication enhanced by PMNs was completely inhibited. CCL2 and interleukin 10 (IL‐10) were produced in cultures of PMNs exposed to R5 HIV, and the replication of R5 HIV was greatly enhanced in MDM cultures supplemented with a mixture of recombinant CCL2 and IL‐10. However, CCL2 and IL‐10 were not produced by PMNs exposed to R5 HIV, when GL was added to the cultures. In the presence of GL, these soluble factors were not detected in co‐cultures of MDMs and PMNs exposed to R5 HIV. In addition, the replication of R5 HIV in MDMs stimulated with CCL2 and IL‐10 was not directly influenced by GL. These results indicated that GL suppresses the PMN‐dependent increase of R5 HIV replication in MDMs through inhibiting CCL2/IL‐10 production by PMNs stimulated with R5 HIV.
Application of Hermeneutics to Studying An Experience Mining Process
Authors: Linden Tanya , Cybulski Jacob L
Published: June 2009

In this paper we investigate an approach to eliciting practitioners’ problem-solving experience across an application domain. The approach is based on a well-known ‘pattern mining’ process which commonly results in a collection of sharable and reusable ‘design patterns’. While pattern mining has been recognised to work effectively in numerous domains, its main problem is the degree of technical proficiency that few domain practitioners are prepared to master. In our approach to pattern mining, patterns are induced indirectly from designers’ experience, as determined by analysing their past projects, the problems encountered and solutions applied in problem rectification. Through the cycles of hermeneutic revisions, the pattern mining process has been refined and ultimately its deficiencies addressed. The hermeneutic method used in the study has been clearly shown in the paper and illustrated with examples drawn from the multimedia domain. The resulting approach to experience elicitation provided opportunities for active participation of multimedia practitioners in capturing and sharing their design experience.
A laboratory and theoretical study of protonated carbon disulfide, HSCS+
Authors: McCarthy M. C. , Thaddeus P. , Wilke Jeremiah J. , Schaefer Henry F.
Published: June 2009

The rotational spectrum of protonated carbon disulfide, HSCS+, has been detected in the centimeter-wave band in a molecular beam by Fourier transform microwave spectroscopy. Rotational and centrifugal distortion constants have been determined from ten transitions in the Ka=0 ladder of the normal isotopic species, HS13CS+, and DSCS+. The present assignment agrees well with high-level coupled cluster calculations of the HSCS+ structure, which, like earlier work, predict this isomer to be the ground state on the HCS2+ potential energy surface; HCSS+, an isomer with C2v symmetry, is predicted to lie more than 20 kcal/mol higher in energy. Other properties of HSCS+ including its dipole moment, anharmonic vibrational frequencies, and infrared intensities have also been computed at the coupled cluster level of theory with large basis sets. Because carbon disulfide possesses a fairly large proton affinity, and because this nonpolar molecule may plausibly exist in astronomical sources, HSCS+ is a good candidate for detection with radio telescopes in the submillimeter band where the stronger b-type transitions of this protonated cation are predicted to lie.
A new water anomaly: The temperature dependence of the proton mean kinetic energy
Authors: Flammini D. , Ricci M. A. , Bruni F.
Published: June 2009

In a recent article [Pietropaolo et al., Phys. Rev. Lett.100, 127802 (2008)] we discussed the results of a deep inelastic neutron scattering experiment aimed at the measure of mean kinetic energy, ⟨Ek⟩, and momentum distribution of protons in supercooled water. The observed excess of proton mean kinetic energy, with respect to theoretical predictions and measurements in water stable liquid and solid phases, suggested a possible link between the anomalous temperature dependence of water density and the temperature dependence of ⟨Ek⟩. Nevertheless, the limited number of data did not allow a more quantitative description. Here we report on new measurements, above and below the temperature of maximum density and in the supercooled phase. These show two ⟨Ek⟩ maxima: The first one, in the supercooled phase in the range of 269–272 K, and a second one at 277 K, the temperature of the maximum density of water.
Charging and discharging in ion implanted dielectric films used for capacitive radio frequency microelectromechanical systems switch
Authors: Li Gang , San Haisheng , Chen Xu-yuan
Published: June 2009

In this work, metal-insulator-semiconductor (MIS) capacitor structure was used to investigate the dielectric charging and discharging in the capacitive radio frequency microelectromechanical switches. The insulator in MIS structure is silicon nitride films (SiN), which were deposited by either low pressure chemical vapor deposition (LPCVD) or plasma enhanced chemical vapor deposition (PECVD) processes. Phosphorus or boron ions were implanted into dielectric layer in order to introduce impurity energy levels into the band gap of SiN. The relaxation processes of the injected charges in SiN were changed due to the ion implantation, which led to the change in relaxation time of the trapped charges. In our experiments, the space charges were introduced by stressing the sample electrically with dc biasing. The effects of implantation process on charge accumulation and dissipation in the dielectric are studied by capacitance-voltage (C-V) measurement qualitatively and quantitatively. The experimental results show that the charging and discharging behavior of the ion implanted silicon nitride films deposited by LPCVD is quite different from the one deposited by PECVD. The charge accumulation in the dielectric film can be reduced by ion implantation with proper dielectric deposition method.
Monte-Carlo-based spectral gain analysis for terahertz quantum cascade lasers
Authors: Jirauschek Christian , Lugli Paolo
Published: June 2009

Employing an ensemble Monte Carlo transport simulation, we self-consistently analyze the spectral gain for different terahertz quantum cascade laser structures, considering bound-to-continuum as well as resonant phonon depopulation designs. In this context, we investigate temperature dependent gain broadening, affecting the temperature performance of terahertz structures. Furthermore, we discuss the influence of the individual scattering mechanisms, such as electron-electron, impurity and interface roughness scattering. A comparison of the simulation results to experimental data yields good agreement.
Electrical properties and interfacial structure of epitaxial LaAlO3 on Si (001)
Authors: Reiner J. W. , Posadas A. , Wang M. , Sidorov M. , Krivokapic Z. , Walker F. J. , Ma T. P. , Ahn C. H.
Published: June 2009

The dielectric and structural properties of LaAlO3 make it an attractive epitaxial gate oxide for nanometer-scale field effect transistors. However, the growth of epitaxial LaAlO3 directly on Si has not been possible to date. In order to achieve LaAlO3 epitaxy, we use a SrTiO3 template layer whose thickness minimizes elastic strain and atomic-level buckling at the interface. We find that LaAlO3 grown on this template layer is crystalline and initially strained, but relaxes to its bulk lattice constant within 7 unit cells. Cross-sectional transmission electron microscopy and inelastic electron tunneling spectroscopy studies of the LaAlO3/SrTiO3/Si structure show no evidence of an amorphous SiO2 layer. Capacitance-voltage measurements on thin films of epitaxial LaAlO3/SrTiO3/Si with LaAlO3 thicknesses between 13 and 110 nm show a dielectric constant for the LaAlO3 layer of 24, the same value as for the bulk. After a post-deposition low temperature anneal, these oxide heterostructures show no Fermi level pinning and an interface state density of ∼8×1010 cm−2 eV−1.
Optical characterization of thin nickel films on polymer substrates using reflectance difference spectroscopy
Authors: Rinnerbauer V. , Schmidegg K. , Hohage M. , Sun L. D. , Flores-Camacho J. M. , Zeppenfeld P.
Published: June 2009

We have used reflectance difference spectroscopy (RDS) and its extension, azimuth-dependent RDS (ADRDS), to study the properties of sputtered and evaporated nickel films on biaxially oriented poly(ethylene terephtalate) (PET) films in a roll to roll web-coating process. From the full set of ADRDS spectra we extract and analyze both the intrinsic RDS spectra and the azimuthal orientation of the effective optical anisotropy of the samples. From the latter, contributions to the RDS spectra arising from the nickel layer and the PET substrate with different orientations of the optical eigenaxes can be inferred. We find an attenuation of the characteristic RDS signal of the PET substrate with increasing nickel film thickness which is in good agreement with the theoretical prediction. For film thicknesses above 20 nm another contribution to the RDS signal attributed to the optical anisotropy of the deposited nickel layers can be observed. Its strength depends on the deposition method, and is considerably larger for evaporated films than for sputtered ones. With increasing nickel film thickness, the azimuthal orientation of the sample anisotropy changes from the initial value of the PET substrate by about 20° toward the machine direction of the foil. We demonstrate that RDS is also a valuable tool for inline monitoring in the roll to roll process, as the attenuation of the RDS signal, under proper consideration of the orientation of the effective anisotropy, is a function of the film thickness and characteristic for the deposited material.
Three dimensional potential distribution and quantized acoustoelectric current for a Al0.3Ga0.7As/GaAs two-dimensional electron gas heterostructure
Authors: Guo Hua-Zhong , Gao Jie , Lu Chuan
Published: June 2009

We present the numerical results for the electrostatic potential distribution in AlGaAs/GaAs heterostructure with double split gates on the surface. The results are obtained from the self-consistent solution of the three dimensional Schrödinger–Poisson equation. The dependence of the potential on the applied gate voltages is discussed in detail. We pay special attention to the potential distribution along the electron transport direction in quasi-one-dimensional channel. The potential barrier heights calculated in the closed-channel-regime agree well with our experiment. The calculations show that the potential barrier height as a function of gate voltage differs strongly in the open-channel regime and the closed-channel regime. On the other hand, we calculate the quantized acoustic current by using the potential barrier obtained from self-consistent solution rather than using the simple analytical model. The results show that the quantized plateau accuracy is about 10−5–10−4 within the minimum slope of the current plateau.
Mechanism and kinetics of the reduction of magnetite to iron during heating in a microwave E-field maximum
Authors: Stir M. , Ishizaki K. , Vaucher S. , Nicula R.
Published: June 2009

The time-resolved x-ray diffraction method was applied in situ to investigate the carbothermal reduction of magnetite by carbon black in a 2.45 GHz microwave field. The kinetics of the phase transformation sequence is analyzed within the Kolmogorov–Johnson–Mehl–Avrami formalism. The first reduction stage is the solid-state transition of magnetite to wüstite, followed by the partial conversion of nearly stoichiometric wüstite to iron. The kinetics of the initial reduction of Fe3O4 to primary wüstite is phase boundary controlled. Behind the reaction front, primary wüstite rapidly evolves toward stoichiometric FeO. Cation vacancies and the dynamic clustering of structural defects influence the kinetics of the reduction of the nearly stoichiometric secondary wüstite to porous iron.
Dielectric spectra of manganese thiophosphate intercalated with sodium ions
Authors: Silipigni L. , Schirò L. , Quattrone T. , Grasso V. , Salvato G. , Monsù Scolaro L. , De Luca G.
Published: June 2009

Sodium intercalated manganese thiophosphate Na0.62Mn0.69PS3 powders have been synthesized by a two-step ion-exchange process. Dielectric measurements have been performed as a function of both temperature and frequency on the prepared samples in the 20–106 Hz frequency range over the 78–350 K temperature range by using the autobalancing bridge method. The temperature dependence of the dielectric constant imaginary part reveals the presence of a loss peak at the low temperatures together with a strong dispersion at the low frequencies and at the highest investigated temperatures. While the loss peak presence is characteristic for dipolar polarization processes, the strong low frequency dispersion at not very high temperatures, observed also in the dielectric constant real part, is typical for system with hopping charge carriers. A hypothesis about the nature of such carriers has been formulated on the basis of both the ion-exchange intercalation process and the comparison with the dielectric spectra previously observed for cesium intercalated manganese thiophosphate Cs0.46Mn0.77PS3 compounds.
Crystallization of sputtered-deposited and ion implanted amorphous Ge2Sb2Te5 thin films
Authors: Rimini E. , De Bastiani R. , Carria E. , Grimaldi M. G. , Nicotra G. , Bongiorno C. , Spinella C.
Published: June 2009

X-ray diffraction and transmission electron microscopy have been utilized to measure the ion irradiation-induced modification in amorphous Ge2Sb2Te5 thin films. The isothermal crystallization of sputtered-deposited and Sb+ ion irradiated amorphous samples has been studied, focusing on the evolution of the microstructure during the initial stage of the transformation. In both samples, the amorphous to crystal transition occurs through the nucleation of face centered cubic (fcc) crystal domains at the film surface. A fast bidimensional growth of the crystalline nuclei in the sputtered-deposited films occurs by the generation of transrotational grains. The lattice parameter decreases as the crystalline fraction increases above 80%, and it approaches the fcc bulk value at the end of the transformation. Ion irradiation produces a densification of the deposited amorphous film (∼4% vertical shrinkage measured by atomic force microscopy) and an enhancement of the crystallization rate. Even in the irradiated amorphous, the nucleation occurs at the film surface and proceeds by the growth of the grains through the thickness of the layer although the density of the transrotational grains is strongly reduced with respect to the unirradiated amorphous. A link between the ion beam induced densification and the reduction of transrotational grains is proposed.
Effect of surface charge on water film nanoconfined between hydrophilic solid surfaces
Authors: Liu Shuhai , Luo Jianbin , Xie Guoxin , Guo Dan
Published: June 2009

The effect of surface charge on the water film confined between hydrophilic solid surfaces has been investigated using thin film interferometry. Experimental results indicate that the higher surface charge density induces the thicker water film for model surfaces, silica, and alumina. It is thought that the strong surface field induced by the surface charge establishes a more ordered hydrogen-bonding network that promotes the forming of thicker water lubrication film between hydrophilic solid surfaces.
Symmetry-adapted density matrix renormalization group calculations of the primary excited states of poly(para-phenylene vinylene)
Authors: Bursill Robert J. , Barford William
Published: June 2009

The Pariser–Parr–Pople model of π-conjugated electrons is solved by a three-block, symmetry-adapted density matrix renormalization group (DMRG) method for the light emitting polymer, poly(para-phenylene vinylene). The energies of the primary excited states are calculated. There is excellent agreement between theory and experiment when solid state screening is incorporated into the model parameters, enabling us to make an identification of the origin of the key spectroscopic features. Appendices describe important technical aspects of the three-block DMRG approach: Local Hilbert space efficiency and its relation to the matrix product formulation of the DMRG; an efficient computational procedure for constructing symmetry-adapted states for DMRG calculations; and correct superblock state targeting to ensure good convergence of the method.
Exciton-phonon coupling in molecular crystals: Synergy between two intramolecular vibrational modes in quaterthiophene single crystals
Authors: Silvestri Leonardo , Tavazzi Silvia , Spearman Peter , Raimondo Luisa , Spano Frank C.
Published: June 2009

Exciton-phonon (EP) coupling in molecular crystals is investigated in the case where two intramolecular vibrational modes are involved and a theoretical model is presented which applies when one of the modes is strongly coupled to crystal excitons. The model is used to simulate the low energy portion of the absorption spectra of quaterthiophene (4T) single crystals, for which we find it appropriate to consider a low energy vibrational mode at 161 cm−1 and an effective strongly coupled high energy mode at 1470 cm−1. Our numerical results demonstrate that the high energy mode renormalizes the excitonic band, thereby strongly affecting the environment seen by the low energy mode and the overall EP coupling regime. Numerical simulations also confirm the existence of the new coupling regimes “intermediate-I” and “strong-I” already introduced for oligothiophene aggregates [Spano et al., J. Chem. Phys. 127, 184703 (2007)], which arise as a consequence of the large effective mass of low energy excitons in 4T crystals. Comparison with experimental high resolution absorption spectra is also reported and shown to support the model predictions.
All-silicon integrated Fabry–Pérot cavity for volume refractive index measurement in microfluidic systems
Authors: St-Gelais R. , Masson J. , Peter Y.-A.
Published: June 2009

We report a refractive index (RI) sensor based on the use of vertically etched silicon Bragg reflectors. The device is robust and performs measurements through tens of micrometers of liquid. A sensitivity of 907 nm/RIU (RI units) and a resolution of 1.7×10−5 RIU are obtained and are in good agreement with optical simulations. This resolution is the highest reported for a volume RI sensor integrated with a microfluidic system. Expected applications for the sensor in the fields of single cell characterization and chip based liquid chromatography are discussed.
Implicitly charge-conserving solver for Boltzmann electrons
Authors: Carlsson Johan , Manente Marco , Pavarin Daniele
Published: June 2009

An implicitly charge-conserving algorithm has been developed for solving the nonlinear Poisson equation that results from the use of Boltzmann electrons. The new algorithm solves for the Boltzmann density parameter and, in the case of a Neumann boundary condition, the surface-charge density, simultaneously as it solves for the discretized electrostatic potential. Numerical stability is demonstrated for time steps exceeding the electron plasma period and spatial resolutions much coarser than the Debye length.