Mg incorporation induced microstructural evolution of reactively sputtered GaN epitaxial films to Mg-doped GaN nanorods.

Mg-doped GaN films/nanorods were grown epitaxially onc-sapphire by reactive co-sputtering of GaAs and Mg at different N2percentages in Ar-N2sputtering atmosphere. Energy dispersive x-ray spectroscopy revealed that the Mg incorporation increases with increase of Mg area coverage of GaAs target, but does not depend on N2percentage. In comparison to undoped GaN films, Mg-doped GaN displayed substantial decrease of lateral conductivity and electron concentration with the initial incorporation of Mg, indicatingp-type doping, but revealed insulating behaviour at larger Mg content. Morphological investigations by scanning electron microscopy have shown that the films grown with 2%-4% Mg area coverages displayed substantially improved columnar structure, compared to undoped GaN films, along with rough and voided surface features at lower N2percentages. With increase of Mg area coverage to 6%, the growth of vertically aligned and well-separated nanorods, terminating with smooth hexagonal faces was observed in the range of 50%-75% N2in sputtering atmosphere. High-resolution x-ray diffraction studies confirmed the epitaxial character of Mg-doped GaN films and nanorods, which displayed completec-axis orientation of crystallites and a mosaic structure, aligned laterally with thec-sapphire lattice. The catalyst-free growth of self-assembled Mg-doped GaN nanorods is attributed to increase of surface energy anisotropy due to the incorporation of Mg. However, with further increase of Mg area coverage to 8%, the nanorods revealed lateral merger, suggesting enhanced radial growth at larger Mg content.

Growth and photocatalytic behavior of transparent reduced GO-ZnO nanocomposite sheets.

Reduced graphene oxide-zinc oxide (rGO-ZnO) nanocomposites were grown on solid substrates by rapid thermal treatment of Langmuir-Blodgett transferred GO-Zn composite sheets in oxygen ambient. The changes induced by uptake of Zn2+ ions and subsequent thermal treatment on surface morphology, micro-structure, composition and optical properties of composite sheets were investigated by atomic force microscopy, high resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectra (XPS), Fourier transform infrared (FT-IR) and Raman measurements. The morphological features of composites are practically independent of subphase Zn concentration and are largely determined by the temperature of rapid thermal treatment. FT-IR results indicate the presence of zinc carboxylate in composites and HR-TEM results confirm the formation of ZnO nanoparticles upon subsequent oxidation. XPS and Raman measurements show that rapid thermal treatment in oxygen ambient results in decrease of carbon-oxygen functional groups and increase in graphitic carbon content leading to the reduction of GO in the composites. The average optical transmittance of rGO-ZnO composites in the visible region is found to be ∼87%. Photocatalytic studies carried out on methylene blue (MB) overlayer coated rGO-ZnO composites show reduction in concentration of MB with increasing duration of UV irradiation. The transparent two-dimensional rGO-ZnO composite solid state structures thus facilitate efficient adsorption and degradation of MB molecules, without any composite aggregation.

Mapping of fruit length related QTLs in interspecific cross (Capsicum annuum L. × Capsicum galapagoense Hunz.) of chilli.

Fruit length in chilli is quantitatively inherited trait and selection based on phenotypic performance is tedious and time consuming. To detect QTLs determining fruit length in Capsicum spp., an interspecific F2 mapping population was developed from the cross of C. annuum L. cv. 'FL 201' with C. galapagoense Hunz. accession 'TC 07245'. Fruit length in this cross showed a quantitative inheritance with the population depicting a symmetric distribution in histogram. To map quantitative trait loci (QTLs) for fruit length 400 SSR markers were surveyed on the parental genotypes but only 28 markers were observed to be polymorphic indicating less genetic diversity between the two Capsicum species. Polymorphic markers were then analyzed in F2 population consisting of 210 plants and 24 of these markers were mapped on to three linkage groups (LGs): LG 1, LG 2 and LG 3. Two fruit length determining QTLs designated as paufl2.1 and paufl2.2 were identified and both the QTLs were mapped on to LG 2. The two QTLs together explained 21.78 per cent of the phenotypic variation. Apart from the two QTLs, positive alleles were detected in the small fruited parent 'TC 07245' which might be of potential use in chilli breeding programs.

Field Evaluation of Pyriproxyfen Against Mosquitoes in Catch Basins in Southern California.

In a field trial, pyriproxyfen (Sumilarv 0.5% G) applied at 10 g and 50 g per catch basin and S-methoprene (Altosid XR briquet 2.1%) at 1 briquet per catch basin at a local park provided 100% inhibition of adult emergence (IAE) of the test species, Culex quinquefasciatus , for the first 3 wk. The IAE dropped to 69% to 85% for pyriproxyfen and 68% for methoprene at 4 wk posttreatment. The IAE at 5 to 8 wk posttreatment, although remaining high, was overshadowed by high mortality in control catch basins. The high mortality in control could be attributed to autodissemination of pyriproxyfen by mosquitoes from treated to untreated catch basins.

Near room temperature reduction of graphene oxide Langmuir-Blodgett monolayers by hydrogen plasma.

Langmuir-Blodgett monolayer sheets of graphene oxide (GO) were transferred onto Si and SiO2/Si, and subjected to hydrogen plasma treatment near room temperature. GO monolayers were morphologically stable at low power (15 W) plasma treatment, for durations up to 2 min and temperatures up to 120 °C. GO monolayers reduced under optimized plasma treatment conditions (30 s duration at 50 °C) exhibit a sheet thickness of (0.5-0.6) nm, high sp(2)-C content (75%), a low O/C ratio (0.16) and a significant red-shift of Raman G-mode to 1588 cm(-1), indicating efficient de-oxygenation and a substantial decrease of defects. A study of the valence band electronic structure of hydrogen plasma reduced GO monolayers shows an increase of DOS in the vicinity of the Fermi level, due to the increase of C 2p-π states, and a substantial decrease of work function. These results, along with conductivity measurements and transfer characteristics, reveal the p-type nature of hydrogen plasma reduced GO monolayers, displaying a conductivity of (0.2-31) S cm(-1) and a field effect mobility of (0.1-6) cm(2) V(-1) s(-1). Plasma treatment at higher temperatures results in a substantial increase in sp(3)-C/damaged alternant hydrocarbon content and incorporation of defects related to the hydrogenation of the graphitic network, as evidenced by multiple Raman features, including a large red-shift of D-mode to 1331 cm(-1) and a high I(D)/I(G) ratio, and supported by the appearance of mid-gap states in the vicinity of the Fermi level.

Ketamine-induced prevention of SD-associated late infarct progression in experimental ischemia.

Spreading depolarizations (SDs) occur frequently in patients with malignant hemispheric stroke. In animal-based experiments, SDs have been shown to cause secondary neuronal damage and infarct expansion during the initial period of infarct progression. In contrast, the influence of SDs during the delayed period is not well characterized yet. Here, we analyzed the impact of SDs in the delayed phase after cerebral ischemia and the potential protective effect of ketamine. Focal ischemia was induced by distal occlusion of the left middle cerebral artery in C57BL6/J mice. 24 h after occlusion, SDs were measured using electrocorticography and laser-speckle imaging in three different study groups: control group without SD induction, SD induction with potassium chloride, and SD induction with potassium chloride and ketamine administration. Infarct progression was evaluated by sequential MRI scans. 24 h after occlusion, we observed spontaneous SDs with a rate of 0.33 SDs/hour which increased during potassium chloride application (3.37 SDs/hour). The analysis of the neurovascular coupling revealed prolonged hypoemic and hyperemic responses in this group. Stroke volume increased even 24 h after stroke onset in the SD-group. Ketamine treatment caused a lesser pronounced hypoemic response and prevented infarct growth in the delayed phase after experimental ischemia. Induction of SDs with potassium chloride was significantly associated with stroke progression even 24 h after stroke onset. Therefore, SD might be a significant contributor to delayed stroke progression. Ketamine might be a possible drug to prevent SD-induced delayed stroke progression.

Blood-brain barrier opening to large molecules does not imply blood-brain barrier opening to small ions.

Neuroimaging of exogenous tracer extravasation has become the technique of choice in preclinical and clinical studies of blood-brain barrier permeability. Such tracers have a larger molecular weight than small ions, neurotransmitters and many drugs. Therefore, it is assumed that tracer extravasation indicates both permeability to these and the cancelation of the electrical polarization across the barrier. Electrophysiological anomalies following intracarotideal administration of dehydrocholate, a bile salt causing extravasation of the albumin-binding tracer Evans blue, seemingly supported this. By contrast, electron microscopic studies suggested a different hierarchical pattern of blood-brain barrier dysfunction, a milder degree of impairment being characterized by increased function of the transcellular pathway and a severe degree by opening of the tight junctions. This would imply that the extravasation of macromolecules can occur before disruption of the electrical barrier. However, functional evidence for this has been lacking. Here, we further investigated the electrophysiological anomalies following intracarotideal application of dehydrocholate in rats and found that it caused focal cerebral ischemia by middle cerebral artery thrombosis, the electrophysiological recordings being characteristic of long-lasting spreading depolarization. These observations indicated that intracarotideal dehydrocholate is not a suitable model to study the isolated dysfunction of the blood-brain barrier. Second, we studied the topical application of dehydrocholate to the brain and the application of mannitol into the carotid artery. In both models, we found significant extravasation of Evans blue but no changes in either extracellular potassium or the CO(2)-dependent intracortical direct current deflection. The latter is assumed to depend on the proton gradient across the barrier in rats which we confirmed in additional experiments in vivo and in vitro. The stability of the extracellular potassium concentration and the CO(2)-dependent direct current deflection are two functional tests which indicate the integrity of the electrical barrier. Hence, our results provide functional evidence that the blood-brain barrier opening to large molecules does not necessarily imply the opening to small ions consistent with the hierarchy of damage in the previous electron microscopic studies.

Study of simultaneous reduction and nitrogen doping of graphene oxide Langmuir-Blodgett monolayer sheets by ammonia plasma treatment.

Graphene oxide (GO) monolayer sheets, transferred onto Si by the Langmuir-Blodgett technique, were subjected to ammonia plasma treatment at room temperature with the objective of simultaneous reduction and doping. Scanning electron microscopy and atomic force microscopy studies show that plasma treatment at a relatively low power (∼10 W) for up to 15 min does not affect the morphological stability and monolayer character of GO sheets. X-ray photoelectron spectroscopy has been used to study de-oxygenation of GO monolayers and the incorporation of nitrogen in graphitic-N, pyrrolic-N and pyridinic-N forms due to the plasma treatment. The corresponding changes in the valence band electronic structure, density of states at the Fermi level and work function have been investigated by ultraviolet photoelectron spectroscopy. These studies, supported by Raman spectroscopy and electrical conductivity measurements, have shown that a short duration plasma treatment of up to 5 min results in an increase of sp²-C content along with a substantial incorporation of the graphitic-N form, leading to the formation of n-type reduced GO. Prolonged plasma treatment for longer durations results in a decrease of electrical conductivity, which is accompanied by a substantial decrease of sp²-C and an increase in defects and disorder, primarily attributed to the increase in pyridinic-N content.

Tuberculosis in CBA/J mice.

Tuberculosis (TB) develops in 5% to 10% of people infected with Mycobacterium tuberculosis (M.tb), but we do not understand how TB develops. CBA/J mice may model these events, as sick mice share features with TB patients, including weight loss, M.tb growth, extensive granulomatous infiltrates, neutrophils, necrosis, and fibrosis. Here, M.tb-infected CBA/J mice were categorized clinically: those with no signs or those with 10% weight loss to determine whether clinical state was associated with lung lesions. The type and distribution of infiltrates (granulomatous with lymphoid aggregates and scattered neutrophils) were similar in mice with weight loss and in mice with no signs. The amount of infiltration and neutrophil foci were higher in mice with weight loss than in mice with no clinical signs. Necrosis and fibrosis were only identified in mice that lost weight. Our results suggest that CBA/J mice may be useful to determine if and how neutrophils contribute to TB disease progression in mouse models.

Growth of CdS nanocrystallites on graphene oxide Langmuir-Blodgett monolayers.

Large area GO-Cd composite Langmuir-Blodgett monolayers were transferred onto Si substrate by introducing Cd(2+) ions into the subphase. The changes in the behaviour of the Langmuir monolayer isotherm in the presence of Cd(2+) ions are attributed to changes in the microstructure and density of the GO sheets on the subphase surface. The uptake of Cd onto the GO monolayers and the effect of subsequent sulphidation were investigated by AFM, FTIR, Raman, XPS and HRTEM techniques. The incorporation of Cd into the GO monolayers causes some overlapping of sheets and extensive formation of wrinkles. Sulphidation of the GO-Cd sheets results in the formation of uniformly distributed CdS nanocrystallites on the entire basal plane of the GO monolayers. The de-bonding of Cd with oxygen functional groups results in a reduction of the wrinkles. The GO sheets function primarily as a platform for the interaction of metal ions with oxygen functionalities and their structure and characteristic features are not affected by either uptake of Cd or formation of CdS.

Endothelin-1(1-31) induces spreading depolarization in rats.

BACKGROUND: The vasoconstrictor endothelin-1(1-21) (ET-1) seems to induce cerebral vasospasm after aneurismal subarachnoid hemorrhage (aSAH). Moreover, ET-1 causes spreading depolarization (SD) via vasoconstriction/ischemia. ET-1(1-31) is an alternate metabolic intermediate in the generation of ET-1. Our aim was to investigate whether endothelin-1(1-31) causes SD in a similar fashion to ET-1. METHOD: Increasing concentrations of either ET-1, ET-1(1-31) or vehicle were brain topically applied in 29 rats. Each concentration was superfused for one hour while regional cerebral blood flow (rCBF) and direct current electrocorticogram (DC-ECoG) were recorded. FINDINGS: In response to the highest concentration of 10(-6) M, all animals of both ET groups developed typical SD. At concentrations below 10(-6) M only ET-1 induced SD (n=14 of 19 rats). Thus, the efficacy of ET-1(1-31) to induce SD was significantly lower (P<0.001, two-tailed Fisher's Exact Test). CONCLUSIONS: Our findings suggest that ET-1(1-31) less potently induces SD compared to ET-1 which implicates that it is a less potent vasoconstrictor. Speculatively, it could be interesting to shift the metabolic pathway towards the alternate intermediate ET-1(1-31) after aSAH as an alternative strategy to ETA receptor inhibition. This could decrease ET-induced vasoconstriction and SD generation while a potentially beneficial basal ETA receptor activation is maintained.

High performance GZO/p-Si heterojunction diodes fabricated by reactive co-sputtering of Zn and GaAs through the control of GZO layer thickness.

The effect of thickness of Ga doped ZnO (GZO) layer on the performance of GZO/p-Si heterojunctions fabricated by reactive co-sputtering of Zn-GaAs target is investigated. GZO films were deposited at 375 °C with 0.5% GaAs area coverage of Zn target and 5% O2 in sputtering atmosphere. X-ray diffraction and X-ray photoelectron spectroscopy show that c-axis orientation of crystallites, Ga/Zn ratio and oxygen related defects depend substantially on the thickness of films. The 200-350 nm thick GZO films display low carrier concentration ∼1017 cm-3, which increases to >1020 cm-3 for thicker films. The diodes fabricated with >500 nm thick GZO layers display non-rectifying behaviour, while those fabricated with 200-350 nm thick GZO layers display nearly ideal rectification with diode factors of 1.5-2.5, along with, turn-on voltage ∼1 V, reverse saturation current ∼10-5 A, barrier height ∼0.4 eV and series resistance ∼200 Ω. The drastically improved diode performance is attributed to small Ga/Zn ratio (∼0.01) and extremely low dopant activation (∼0.3%), owing to diffusion and non-substitutional incorporation of Ga in thin GZO layers, which cause self-adjustment of doping concentration. These factors, together with c-axis orientation and chemisorbed oxygen at grain boundaries, facilitate ideal diode characteristics, not reported earlier for GZO/p-Si heterojunctions.

Residual Activity of Pyriproxyfen Against Mosquitoes in Catch Basins in Northwestern Riverside County, Southern California.

A field study was carried out on the year-long residual activity of the insect growth regulator (IGR) pyriproxyfen (Nylar 0.5G) in comparison with methoprene (Altosid® XRP Pellets) against mosquito developmental stages in catch basins in northwestern Riverside County, southern California. Pyriproxyfen was applied at 75, 100, 125, 150, 175 g per catch basin and methoprene at 3.5 g per catch basin. A total of 80 catch basins (10 per each treatment and 20 for control) were used. Posttreatment observations of catch basins were carried out at weekly intervals, with all pupal collections reared to adults. Mosquito species composition in this study, consisting mostly of Culex species (693), was predominated by Cx. quinquefasciatus (92.8%), followed by Cx. erythrothorax (5.5%), Cx. tarsalis (1.2%), Cx. stigmatosoma (0.3%), and Cx. thriambus (0.2%). Activity of both IGRs was expressed as percent inhibition of adult emergence (% IAE). Data generated on % IAE showed that, like methoprene, pyriproxyfen provided complete control of mosquitoes at 75, 125, and 175 g per catch basin up to 50 wk posttreatment at the Riverside amusement park, whereas its activity against mosquitoes in catch basins treated with 100 g and 150 g at the Eastvale site was short-lived, up to 48 wk. Water samples, bioassayed against laboratory-reared, 4th-stage larvae of Cx. quinquefasciatus 1-2 wk after the 50-wk-long study, showed evidence of significant % IAE (∼50) by pyriproxyfen at the 2 higher rates (125 g, 175 g) used at the amusement park. In conclusion, pyriproxyfen can be used to effectively control mosquitoes in catch basins for 48-50 wk, depending on the rate of application.

Effect of effluent-treated water on mosquito development in simulated ponds at the Prado Wetlands of southern California.

Studies were conducted to determine the effect of water quality on mosquito development at the Prado Wetlands in southern California during 2003-04. In field experimental ponds, mosquito abundance was significantly higher in the sewage effluent-treated water than in untreated control. As compared to untreated control, treated water had higher dissolved oxygen, total nitrogen, phosphorus, and turbidity, and it showed lower electrical conductivity, sulfate, carbonates, and bicarbonates. Diverse vegetation and invertebrate fauna as influenced by water quality may have contributed to higher mosquito breeding in the treated ponds. In laboratory studies, the treated water did not significantly affect the developmental rate, adult emergence, sex ratio, and overall mortality of Culex quinquefasciatus and Culex tarsalis, known vectors of encephalitides in southern California. However, the ovipositional response, especially of the former species, was numerically higher to the treated than to untreated control water. Besides smaller body size of 3rd/4th instars of both species, 4th-stage larvae of Cx. quinquefasciatus reared in the treated pond water weighed lighter than the control larvae.

[Questionnaire study on the acceptance of a student initiative for computer-based medical education]. / Befragung zur Akzeptanz einer studentischen Initiative für die computerbasierte medizinische Ausbildung.

BACKGROUND AND PURPOSE: Computer-based teaching and learning are getting more and more important in medical education. To integrate this type of training into the curricula, medical faculties must provide supervised computer labs. The present study was conducted to evaluate the acceptance and efficiency of the student-organised concept of computer labs established at the Charité Hospital in Berlin. METHODS: An electronic online questionnaire comprising 25 items was distributed to all users of the two computer labs at the Charité to ask their opinions about the quality of the student-organised concept and their satisfaction with the working conditions in the labs and to compare them longitudinally with the results obtained 4 years ago. RESULTS: A total of 1275 users worked in the labs during the survey period and 702 answered the questionnaire (return rate: 55.1%). The users assigned good to very good ratings to different components of the concept with student self-administration and helpfulness of the student tutors achieving the highest rating (both 1.5 +/- 0.7). In the longitudinal study no component of the concept was rated worse in the current questionnaire, whereas the opening hours were assigned significantly higher ratings than 4 years ago (1.6 +/- 0.8 vs. 2 +/- 0.9; p < 0.001). Over 20% of all users stated they would be interested in actively participating as tutors in the project. Students used the computer labs for a mean of 3.1 hours per week. The support of students working on a voluntary basis allowed for weekly opening hours of the labs of 146 hours with the personnel expenditure costs that would be necessary for the position of one faculty member. CONCLUSIONS: The good to excellent ratings, the high acceptance by users, and the low costs of the project presented here suggest that this student initiative can be recommended to other medical faculties to serve as a basis for integration of computer-based education into the curriculum.

Molecular Genetic Characterization of Thyroid Dyshormonogenesis in a French Bulldog.

BACKGROUND: A case of congenital hypothyroidism with goiter (CHG) in a juvenile French bulldog was identified and hypothesized to be caused by dyshormonogenesis of genetic etiology. OBJECTIVES: To describe case management, unusual phenotypic aspects, and a CHG-causing mutation in a French bulldog. ANIMALS: Thyroid tissue and blood from a CHG-affected French bulldog and 4 normal control dogs and buccal brush samples of 125 French bulldogs were studied. METHODS: Standard clinical assessment and laboratory tests were applied. Thyroid peroxidase (TPO) iodide oxidation activity was measured in vitro, and TPO protein was assessed on Western blots. Thyroid peroxidase exons and flanking splice sites were amplified from genomic DNA and sequenced. Thyroid peroxidase cDNA was amplified from thyroid RNA and sequenced. RESULTS: At 9 months of age, the affected dog had signs of cretinism, but near-normal skeletal maturation. The enlarged thyroid glands exhibited noninflammatory fibrosis and aberrant follicular organization. Thyroid peroxidase activity and immunocrossreactive protein were undetectable. There was a T>C mutation of the intron 12 splice donor consensus that caused abnormally spliced mRNA, consistent with absent TPO function. The mutant allele was not observed in 125 clinically normal French bulldogs. CONCLUSIONS: Presumptive CHG in a French bulldog with unusual clinical presentation is described. Genetic etiology was confirmed by identifying the underlying TPO mutation.

Alterations in plasma transforming growth factor beta in normoalbuminuric type 1 and type 2 diabetic patients.

Transforming growth factor ss (TGF-ss) is an immunosuppressor. It plays a role in regulating cell proliferation, and deletion of its gene in transgenic mice leads to an autoimmune-like disorder. A role of this cytokine has been proposed in the pathogenesis of type 1 diabetes and probably type 2 diabetes. Previous studies had shown an elevated serum level in type 2 diabetes and a reduced serum level in type 1 diabetes; however, these studies did not address the onset of the alterations of TGF-ss with regard to the duration of diabetes. In this study, we compared the levels of TGF-ss in the serum of groups of patients with type 1 and type 2 diabetes mellitus divided according to the duration of their disease. Twenty-six normoalbuminuric patients with type 1 diabetes and 25 normoalbuminuric patients with type 2 diabetes were divided into three groups according to the onset of their diabetes and were compared with 27 and 15 age-matched normal subjects, respectively. We conclude that in normoalbuminuric patients serum TGF-ss levels increased at the onset of type 2 diabetes and remained elevated throughout the disease; they did not change at the onset of type1 diabetes, however, they started to decrease around 2 yr after the onset of the disease.

Drug-related hospitalization at a tertiary teaching center in Lebanon: incidence, associations, and relation to self-medicating behavior.

OBJECTIVE: In Lebanon there is very limited restriction on drug use. Accordingly, self-medication is highly prevalent. This study examined the influence of these factors on the development of drug-related illnesses that lead to hospitalization. METHODS: Patients admitted to the medical and pediatric wards of a tertiary teaching center in Beirut, Lebanon, over a period of 6 months were interviewed and their charts were reviewed. Admissions attributable to adverse drug reactions or therapeutic failures were identified and characterized with respect to demographic factors, medical history, drug intake, and self-medicating behavior. The influence of these variables on the development of drug-related illnesses was examined by logistic regression. RESULTS: Of 1745 adults and 457 children, there were 177 (10.2%) and 36 (7.9%) drug-related illnesses, respectively. Adverse drug reactions accounted for 7.0% and 5.7% and therapeutic failures for 3.2% and 2.2% of adult and pediatric admissions, respectively. Self-medication was commonly practiced (52.6% of adults and 41.6% of children). Logistic regression analysis revealed that female sex increased the risk of adverse drug reaction in adults, whereas self-medication decreased the risk. In children, the risk of adverse drug reaction was increased in lower socioeconomic groups, whereas the risk of therapeutic failure was increased by a positive history of atopy or drug reaction. CONCLUSIONS: These results provide the first detailed analysis of the problem of drug-related illnesses in a developing country and identify a number of related or risk factors. Despite the lack of regulation of drug dispensing and the unchecked access to drugs in Lebanon, the incidence of drug-related illnesses is not different from that in Western nations. This finding may have relevance to policies of drug regulation in other countries.

Comparison of computer workstation with light box for detecting setup errors from portal images.

PURPOSE: Observer studies were conducted to test the hypothesis that radiation oncologists using a computer workstation for portal image analysis can detect setup errors at least as accurately as when following standard clinical practice of inspecting portal films on a light box. METHODS AND MATERIALS: In a controlled observer study, nine radiation oncologists used a computer workstation, called PortFolio, to detect setup errors in 40 realistic digitally reconstructed portal radiograph (DRPR) images. PortFolio is a prototype workstation for radiation oncologists to display and inspect digital portal images for setup errors. PortFolio includes tools for image enhancement; alignment of crosshairs, field edges, and anatomic structures on reference and acquired images; measurement of distances and angles; and viewing registered images superimposed on one another. The test DRPRs contained known in-plane translation or rotation errors in the placement of the fields over target regions in the pelvis and head. Test images used in the study were also printed on film for observers to view on a light box and interpret using standard clinical practice. The mean accuracy for error detection for each approach was measured and the results were compared using repeated measures analysis of variance (ANOVA) with the Geisser-Greenhouse test statistic. RESULTS: The results indicate that radiation oncologists participating in this study could detect and quantify in-plane rotation and translation errors more accurately with PortFolio compared to standard clinical practice. CONCLUSIONS: Based on the results of this limited study, it is reasonable to conclude that workstations similar to PortFolio can be used efficaciously in clinical practice.

Involvement of capsaicin sensitive primary afferents in thymulin-induced hyperalgesia.

Intraplantar (5 ng) or intraperitoneal (50 ng) injections of thymulin, produced both thermal and mechanical hyperalgesia in rats. In this report, we show that ablation of capsaicin sensitive primary afferents (CSPA) can alter or abolish thymulin-induced hyperalgesia. Different groups of rats were subjected to either treatment with capsaicin or to surgical subdiaphragmatic vagotomy (SDV). Both capsaicin and SDV reduced significantly thymulin-induced hyperalgesia. On the other hand, these treatments elicited differential effects on the modulation by thymulin of the levels of nerve growth factor and interleukin 1beta. We conclude that the hyperalgesic effects of i.p. thymulin are mainly mediated through the CSPA fibers.