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- Author or Editor: J. Welsh x
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Abstract
The scope of NDP can be expanded by measuring (via time-of-flight) the kinetic energies of the recoils emitted from (n,p) or (n,
) reactions. When they occur inside a solid, the energies of the emerging recoils reveal depth from which they originated. The Recoil Nucleus Time-of-Flight NDP (RN-TOF-NDP) technique can reveal the depth distribution of some isotopes (e.g.,10B,210Bi) with a resolution of a few Å. Furthermore, it is possible to detect atomic and molecular species ejected at the surface site where the recoil emerges from the solid. This paper discusses the methodology for RN-TOF-NDP and its applications including surface analysis based on atomic and molecular ions codesorbed with the recoils.
Abstract
The Time-of-Flight (ToF) technique can be used for mass identification, for separation of a specified mass or for measuring the energy of a given mass particle. The instrumentation required is simple and low in cost. The method features high yield, transmission efficiency is typically of 5 to 20%. Even with short flight paths (5 to 10 cm), ToF has adequate mass resolution (M/
M
300 to 500) for identifying isotopic species. This paper examines the scope of ToF in nuclear science with examples in mass spectrometry, in mass separation and in kinetic energy measurements of fixed mass particles. An example of the latter is the energy determination of recoil nuclei. If a recoil is produced inside a solid, the residual recoil energy reveals the depth from which it originates. This approach is used for profiling nitrogen via14N(n, p)14C. The ToF measurement of the14C recoil energies reveals the depth distribution of nitrogen with better than 50 Å resolution.
Abstract
This paper describes first the application of neutron depth profiling (NDP) for measuring the distribution of6Li in LiAlO2 ceramics. Using a surface barrier detector for detecting3H produced in6Li(n, 
)3H,6Li was profiled to a depth of 14 
m in the ceramics. Secondly, a new methodology is presented for NDP with enhanced capabilities based on measuring the energy of recoiling nuclei from (n, p) and (n, ) reactions by time-of-flight mass spectrometry. The scope of recoil nucleus time-of-flight mass spectrometry (RN-TOF-MS) includes profiling of10B,14N,17O,33S,35Cl,40K. Probe depths may be of a few tens nanometers. RN-TOF-MS complements and refines NDP based on charged particle (p or ) spectrometry.
Abstract
Background: The initial treatment of obsessive-compulsive disorder (OCD) has generally been limited to serotonergic agents, cognitive-behavioral therapy (CBT), or a combination of the two. These findings were supported by the POTS study for OCD in children and adolescents. However, treatment with serotonergic agents or CBT can take several weeks before benefit is seen; severe cases of OCD may require more immediate treatment. Case report: The authors present a case of severe OCD in an adolescent that required immediate treatment due to her critical medical condition. The patient's symptoms included not eating or taking medications or fluids by mouth due to fears of contamination. A medical hospitalization was previously required due to dehydration. As treatment with an SSRI would not have quick enough onset and the patient was initially resistant to participating in CBT, the patient was psychiatrically hospitalized and first started on liquid risperidone. After several doses of risperidone, the patient was able to participate in CBT and start sertraline. Discussion: The authors discuss the differential diagnosis of such a patient, including the continuum of OCD symptoms and psychotic symptoms. The authors discuss the different treatment options, including the utilization of inpatient psychiatric hospitalization. The authors discuss the potential risks and benefits of using atypical antipsychotics in lieu of benzodiazepines for the initial treatment of severe adolescent OCD. The authors also discuss other current treatment recommendations and rationale for the treatment that was pursued. Conclusions: This patient received benefit of her symptoms relatively quickly with psychiatric hospitalization and an atypical antipsychotic. The diagnosis of a psychotic disorder should be considered. These treatment options must be weighed against the risks of atypical antipsychotics, including extrapyramidal symptoms, weight gain, and metabolic syndrome; benzodiazepines also have their risks and benefits. Additionally, the cost of time and finances of inpatient hospitalization must be considered. More research is needed regarding the short- and long-term efficacy and safety of antipsychotics in the treatment of OCD in the child and adolescent population.
Abstract
Over the last three years we have developed a very robust nuclear and radiochemistry program at The University of Texas at Austin. The cornerstone of support was the DOE Radiochemistry Educational Award Program (REAP) that was awarded from 2002–2005. A second award for the period of 2005–2008 was just received. This award has enabled us to support many educational activities from vanguard classroom instruction, to laboratory enhancements, to research activities at the graduate and undergraduate levels. Both traditional radiochemistry and advanced topics in nuclear instrumentation have been supported. Various DOE university programs, national lab funding and IAEA fellowship grants, have allowed the Nuclear and Radiation Engineering Program at the University of Texas to be at the forefront of nuclear and radiochemistry educational and research activities and help secure the next generation of needed expertise.
Summary
In the past few years there has been renewed worldwide interest in the re-establishment of various nuclear and radiochemistry disciplines in the hope of training the next generation of skilled researchers in this area. In the United States there continues to be an acute shortage of MSc and PhD level trained students, particularly at the Department of Energy national laboratories. As a result of this critical need the Department of Energy established a Radiochemistry Education Award Program (REAP) in the late 1990's to address this issue. Several universities were awarded funding to establish various complimentary programs. One of the main goals of the REAP at the University of Texas was to establish a web-based graduate level course with associated labs and to have interactions with the national laboratories.
Abstract
Background and aims
Limited treatment options are available for trichotillomania (TTM) and most have modest outcomes. Suboptimal treatment results may be due to the failure of existing approaches to address all TTM styles.
Methods
Thirty-eight DSM-IV TTM participants were randomly assigned across two study sites to Dialectical Behavior Therapy (DBT) -enhanced cognitive-behavioral treatment (consisting of an 11-week acute treatment and 3-month maintenance treatment) or a minimal attention control (MAC) condition. MAC participants had active treatment after the 11-week control condition. Follow-up study assessments were conducted three and six months after the maintenance period.
Results
Open trial treatment resulted in significant improvement in TTM severity, emotion regulation (ER) capacity, experiential avoidance, anxiety and depression with changes generally maintained over time. In the randomized controlled trial, those with active treatment had greater improvement than those in the MAC condition for both TTM severity and ER capacity. Correlations between changes in TTM severity and ER capacity were not reported at post-treatment but did occur in maintenance and follow-up indicating reduced TTM severity with improved ER capacity.
Conclusions
DBT-enhanced cognitive-behavioral treatment is a promising treatment for TTM. Future studies should compare this approach to other credible treatment interventions and investigate the efficacy of this approach in more naturalistic samples with greater comorbidity.
