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1.
J Hosp Infect ; 133: 23-27, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36584942

RESUMEN

Drinking water in hospitals is often tested for Pseudomonas aeruginosa because of its virulence potential. This article describes a case where, based on EN ISO 16266, seven of 11 (64%) samples taken simultaneously from the drinking water system at a single hospital tested positive for P. aeruginosa. This resulted in extensive investigations and interventions, and a number of measures were implemented. However, supplementary analyses with more discriminatory power (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, 16S-rRNA sequencing) ruled out P. aeruginosa completely. The authors wish to raise awareness of this problem, and suggest that diagnostic uncertainty of results obtained by EN ISO 16266 should be indicated on laboratory reports. Wrongly assuming the presence of P. aeruginosa in hospital water supply systems can lead to unnecessary control measures, as analytical uncertainty massively influences the health risk assessment and the remediation measures initiated in medical environments.


Asunto(s)
Agua Potable , Pseudomonas aeruginosa , Humanos , Hospitales , Abastecimiento de Agua , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
2.
Chemistry ; 28(57): e202201761, 2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-35916156

RESUMEN

Herein we report a photo-mediated formal addition of carboxylic acids to activated alkenes catalyzed by a pyrimidopteridine photoredox catalyst. The decarboxylation of aliphatic carboxylic acids upon single-electron oxidation is countered in the presence of electron-rich alkenes and a hydroacetoxylation is observed. Mechanistic proposals have been made based on CV measurements, competitive Stern-Volmer quenching and EPR experiments. Evidence that tetra-N-substituted pyrimidopteridines function as dual photoredox and hydrogen atom transfer catalyst was supported by spectroscopic means.


Asunto(s)
Alquenos , Ácidos Carboxílicos , Alquenos/química , Ácidos Carboxílicos/química , Catálisis , Hidrógeno/química , Oxidación-Reducción
3.
ESMO Open ; 7(1): 100336, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34953399

RESUMEN

INTRODUCTION: Microsatellite instability (MSI) testing and tumor mutational burden (TMB) are genomic biomarkers used to identify patients who are likely to benefit from immune checkpoint inhibitors. Pembrolizumab was recently approved by the Food and Drug Administration for use in TMB-high (TMB-H) tumors, regardless of histology, based on KEYNOTE-158. The primary objective of this retrospective study was real-world applicability and use of immunotherapy in TMB/MSI-high patients to lend credence to and refine this biomarker. METHODS: Charts of patients with advanced solid tumors who had MSI/TMB status determined by next generation sequencing (NGS) (FoundationOne CDx) were reviewed. Demographics, diagnosis, treatment history, and overall response rate (ORR) were abstracted. Progression-free survival (PFS) was determined from Kaplan-Meier curves. PFS1 (chemotherapy PFS) and PFS2 (immunotherapy PFS) were determined for patients who received immunotherapy after progressing on chemotherapy. The median PFS2/PFS1 ratio was recorded. RESULTS: MSI-high or TMB-H [≥20 mutations per megabase (mut/MB)] was detected in 157 adults with a total of 27 distinct tumor histologies. Median turnaround time for NGS was 73 days. ORR for most recent chemotherapy was 34.4%. ORR for immunotherapy was 55.9%. Median PFS for patients who received chemotherapy versus immunotherapy was 6.75 months (95% confidence interval, 3.9-10.9 months) and 24.2 months (95% confidence interval, 9.6 months to not reached), respectively (P = 0.042). Median PFS2/PFS1 ratio was 4.7 in favor of immunotherapy. CONCLUSION: This real-world study reinforces the use of TMB as a predictive biomarker. Barriers exist to the timely implementation of NGS-based biomarkers and more data are needed to raise awareness about the clinical utility of TMB. Clinicians should consider treating TMB-H patients with immunotherapy regardless of their histology.


Asunto(s)
Inmunoterapia , Inestabilidad de Microsatélites , Neoplasias , Adulto , Biomarcadores de Tumor/genética , Humanos , Neoplasias/genética , Neoplasias/terapia , Estudios Retrospectivos
4.
Clin Radiol ; 76(9): 674-680, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34120732

RESUMEN

AIM: To assess pain relief and local tumour control retrospectively in spinal metastases undergoing cryoablation. MATERIALS AND METHODS: Between May 2008 and September 2020, 46 metastases in 41 consecutive patients (mean age 59.7±4.4 [SD] years; range 27-84) were treated with cryoablation in 42 interventional sessions. Patient demographics, procedural data, complications, pain, and local tumour control were analysed retrospectively. RESULTS: Thirty-one patients (36 spine metastases; 32 sessions) were treated for pain relief and 10 (10 metastases; 10 sessions) for local tumour control. Clinical success was reached in 30/32 (93.8%) interventional palliative sessions. Mean pre-procedural numerical pain rate scale was 6.2±1.7 (SD), and dropped significantly to 3.5±1.8 (SD), 1.9±1.7 (SD), and 1.9±1.8 (SD) at 24-h, 1-month and at the last available follow-up (median 16.5±23.2 [SD] months), respectively. For patients requiring local tumour control, primary clinical success was reached in 6/10 (60%) spinal metastases at median 25-months follow-up. The overall complication rate was 8%, with no secondary fractures or iatrogenic thermal-mediated nerve injuries reported. CONCLUSION: Percutaneous image-guided cryoablation of spinal metastases is safe and effective in achieving pain relief and local tumour control.


Asunto(s)
Criocirugía/métodos , Manejo del Dolor/métodos , Dolor/cirugía , Radiología Intervencionista/métodos , Neoplasias de la Columna Vertebral/secundario , Neoplasias de la Columna Vertebral/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor/etiología , Estudios Retrospectivos , Neoplasias de la Columna Vertebral/complicaciones , Resultado del Tratamiento
5.
J Sex Med ; 18(3): 632-645, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33642235

RESUMEN

BACKGROUND: The number of adolescents presenting with gender dysphoria (GD) in healthcare services has increased significantly, yet specialized services offering transition-related care (TRC) for trans youth is lacking. AIM: To investigate satisfaction with TRC, regret, and reasons for (dis)satisfaction with transition-related medical interventions (TRMIs) in trans adolescents who had presented to the Hamburg Gender Identity Service for children and adolescents (Hamburg GIS). METHODS: Data were collected from a clinical cohort sample of 75 adolescents and young adults diagnosed with GD (81% assigned female at birth) aged 11 to 21 years (M = 17.4) at baseline and follow-up (on a spectrum of ongoing care, on average 2 years after initial consultation). To determine progress of the youth's medical transitions, an individual treatment progress score (ITPS) was calculated based on number of desired vs received TRMIs. OUTCOMES: Main outcome measures were satisfaction with TRC at the time of follow-up, ITPS, social support, reasons for regret and termination of TRC, and (dis)satisfaction with TRMIs. RESULTS: Participants underwent different stages of TRMIs, such as gender-affirming hormone treatment or surgeries, and showed overall high satisfaction with TRC received at the Hamburg GIS. Regression analysis indicated that a higher ITPS (an advanced transition treatment stage) was predictive of higher satisfaction with TRC. Sex assigned at birth, age, and time since initial consultation at the clinic showed no significant effects for satisfaction with TRC, while degree of social support showed a trend. No adolescents regretted undergoing treatment at follow-up. Additional analysis of free-text answers highlighted satisfaction mostly with the physical results of TRMI. CLINICAL IMPLICATIONS: Because youth were more satisfied with TRC when their individual transition (ITPS) was more progressed, treatment should start in a timely manner to avoid distress from puberty or long waiting lists. STRENGTHS AND LIMITATIONS: This study is one of the first to report on treatment satisfaction among youth with GD from Europe. The ITPS allowed for a more detailed evaluation of TRMI wishes and experiences in relation to satisfaction with TRC and may close a gap in research on these treatments in adolescent populations. However, all participants were from the same clinic, and strict treatment eligibility criteria may have excluded certain trans adolescents from the study. Low identification rates with non-binary identities prevented comparisons between non-binary and binary genders. CONCLUSION: The study highlights the role of TRMI and individual treatment or transition progress for youth's overall high satisfaction with TRC received at the Hamburg GIS. Nieder TO, Mayer TK, Hinz S, et al. Individual Treatment Progress Predicts Satisfaction With Transition-Related Care for Youth With Gender Dysphoria: A Prospective Clinical Cohort Study. J Sex Med 2021;18:632-645.


Asunto(s)
Disforia de Género , Personas Transgénero , Adolescente , Adulto , Niño , Estudios de Cohortes , Europa (Continente) , Femenino , Disforia de Género/terapia , Identidad de Género , Humanos , Masculino , Satisfacción Personal , Estudios Prospectivos , Adulto Joven
6.
Diagn Interv Imaging ; 102(1): 27-34, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32482583

RESUMEN

PURPOSE: To investigate the safety and clinical efficacy of bipolar radiofrequency ablation (b-RFA) with increased (>70°C) target temperature for the treatment of spine metastases with the intent of achieving pain relief or local tumor control. MATERIALS AND METHODS: Thirty-one patients with a total of 37 metastases who were treated with b-RFA with increased temperature and vertebroplasty from January 2016 to May 2019 were retrospectively included. There were 20 women and 11 men with a mean age of 62.4±10.5 (SD) years (range: 40-78years). Patients and metastases characteristics, procedure details and clinical outcomes were analyzed. RESULTS: Metastases were predominantly located in lumbar (22/37; 59.5%) or thoracic spine (13/37; 35.1%). Mean target temperature was 88.4±3.5 (SD) °C (range: 70-90°C). Technical success was 100% (37/37 metastases). One (1/37; 2.7%) major complication unrelated to b-RFA was reported. One (1/37; 2.7%) metastasis was lost to follow-up. Favorable outcome was noted in patients receiving b-RFA for pain management (16/20 metastases; 80%; mean follow-up, 3.4±2.9 [SD] months) or with oligometastatic/oligoprogressive disease (6/6 metastases; 100%; mean follow-up, 5.0±4.6 [SD] months). In patients receiving b-RFA to prevent complications, favorable outcome was noted in 6/10 metastases (60%; mean follow-up, 3.8±4.8 [SD] months). CONCLUSIONS: B-RFA with increased target temperature has an excellent safety profile and results in high rates of pain relief and local metastasis control in patients with oligometastatic/oligoprogressive disease. Suboptimal results are achieved in patients receiving b-RFA to prevent complications related to the growth of the index tumor.


Asunto(s)
Ablación por Catéter , Ablación por Radiofrecuencia , Neoplasias de la Columna Vertebral , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Manejo del Dolor , Estudios Retrospectivos , Neoplasias de la Columna Vertebral/cirugía , Temperatura , Resultado del Tratamiento
7.
Br J Dermatol ; 184(6): 1153-1160, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33205400

RESUMEN

BACKGROUND: Pemphigus vulgaris (PV) is a life-threatening mucocutaneous autoimmune blistering disease. We previously showed that genetic variants within the ST18 gene promoter area confer a sixfold increase in the propensity to develop PV. ST18, a transcription factor, was found to be overexpressed in the epidermis of patients with PV. In addition, it was found to promote autoantibody-mediated abnormal epidermal cell-cell adhesion and secretion of proinflammatory mediators by keratinocytes. OBJECTIVES: To delineate the mechanism through which ST18 contributes to destabilization of cell-cell adhesion. METHODS: We used quantitative reverse-transcriptase polymerase chain reaction, immunofluorescence microscopy, a luciferase reporter system, site-directed mutagenesis, chromatin immunoprecipitation (ChIP) and the dispase dissociation assay. RESULTS: The ChIP and luciferase reporter assays showed that ST18 directly binds and activates the TNF promoter. Accordingly, increased ST18 expression contributes to PV pathogenesis by destabilizing cell-cell adhesion in a tumour necrosis factor (TNF)-α-dependent fashion. In addition, dual immunofluorescence staining showed increased expression of both ST18 and TNF-α in the skin of patients with PV carrying an ST18-associated PV risk variant, which was found to be associated with a more extensive PV phenotype. CONCLUSIONS: Our findings suggest a role for TNF-α in mediating the deleterious effect of increased ST18 expression in PV skin.


Asunto(s)
Pénfigo , Proteínas Represoras , Autoanticuerpos , Adhesión Celular , Desmogleína 3/genética , Humanos , Queratinocitos , Pénfigo/genética , Regiones Promotoras Genéticas , Factor de Necrosis Tumoral alfa/genética
8.
Oncogene ; 39(11): 2345-2357, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31844249

RESUMEN

Systemic toxicity and tumor cell resistance still limit the efficacy of chemotherapy in colorectal cancer. Therefore, alternative treatments are desperately needed. The thiazolide Nitazoxanide (NTZ) is an FDA-approved drug for the treatment of parasite-mediated infectious diarrhea with a favorable safety profile. Interestingly, NTZ and the thiazolide RM4819-its bromo-derivative lacking antibiotic activity-are also promising candidates for cancer treatment. Yet the exact anticancer mechanism(s) of these compounds still remains unclear. In this study, we systematically investigated RM4819 and NTZ in 2D and 3D colorectal cancer culture systems. Both compounds strongly inhibited proliferation of colon carcinoma cell lines by promoting G1 phase cell cycle arrest. Thiazolide-induced cell cycle arrest was independent of the p53/p21 axis, but was mediated by inhibition of protein translation via the mTOR/c-Myc/p27 pathway, likely caused by inhibition of mitochondrial respiration. While both thiazolides demonstrated mitochondrial uncoupling activity, only RM4819 inhibited the mitochondrial respiratory chain complex III. Interestingly, thiazolides also potently inhibited the growth of murine colonic tumoroids in a comparable manner with cisplatin, while in contrast to cisplatin thiazolides did not affect the growth of primary intestinal organoids. Thus, thiazolides appear to have a tumor-selective antiproliferative activity, which offers new perspectives in the treatment of colorectal cancer.


Asunto(s)
Neoplasias Colorrectales/genética , Transporte de Electrón/genética , Puntos de Control de la Fase G1 del Ciclo Celular/genética , Membranas Mitocondriales/metabolismo , Tiazoles/uso terapéutico , Animales , Humanos , Ratones , Tiazoles/química
9.
Phys Chem Chem Phys ; 20(25): 17180-17187, 2018 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-29900473

RESUMEN

The most limiting factor for the commercialization of perovskite solar cells is the lack of long-term stability under operating conditions. To examine the intrinsic stability of the perovskite film, we investigated the chemical and electronic properties of methylammonium lead triiodide (CH3NH3PbI3) perovskite by in situ X-ray photoelectron spectroscopy (XPS). In particular, XPS data were collected under dark conditions, at applied voltage, under illumination, at open circuit, and under operating conditions. In addition, operation in ambient air atmosphere was analysed by XPS. It was observed that the chemical properties of methylammonium lead triiodide change upon illumination under open-circuit condition by formation of metallic lead species and then by conversion into PbI2 due to evaporation of the organic compounds. These changes, however, can be restricted by applying an extraction voltage to the device contacts that will extract the photogenerated charges from the absorber. As these results were obtained in vacuum, i.e., in an inert atmosphere, experiments prove that the photogenerated charge carriers intrinsically induce changes in chemical and electronic properties if they are not extracted from the absorber. By illuminating CH3NH3PbI3 in ambient air, the metallic lead species react with oxygen and form lead oxides and lead complexes, which passivate the film and remove the in-gap states.

10.
Microbiome ; 5(1): 62, 2017 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-28693587

RESUMEN

BACKGROUND: An inflatable lunar/Mars analog habitat (ILMAH), simulated closed system isolated by HEPA filtration, mimics International Space Station (ISS) conditions and future human habitation on other planets except for the exchange of air between outdoor and indoor environments. The ILMAH was primarily commissioned to measure physiological, psychological, and immunological characteristics of human inhabiting in isolation, but it was also available for other studies such as examining its microbiological aspects. Characterizing and understanding possible changes and succession of fungal species is of high importance since fungi are not only hazardous to inhabitants but also deteriorate the habitats. Observing the mycobiome changes in the presence of human will enable developing appropriate countermeasures with reference to crew health in a future closed habitat. RESULTS: Succession of fungi was characterized utilizing both traditional and state-of-the-art molecular techniques during the 30-day human occupation of the ILMAH. Surface samples were collected at various time points and locations to observe both the total and viable fungal populations of common environmental and opportunistic pathogenic species. To estimate the cultivable fungal population, potato dextrose agar plate counts method was utilized. The internal transcribed spacer region-based iTag Illumina sequencing was employed to measure the community structure and fluctuation of the mycobiome over time in various locations. Treatment of samples with propidium monoazide (PMA; a DNA intercalating dye for selective detection of viable microbial populations) had a significant effect on the microbial diversity compared to non-PMA-treated samples. Statistical analysis confirmed that viable fungal community structure changed (increase in diversity and decrease in fungal burden) over the occupation time. Samples collected at day 20 showed distinct fungal profiles from samples collected at any other time point (before or after). Viable fungal families like Davidiellaceae, Teratosphaeriaceae, Pleosporales, and Pleosporaceae were shown to increase during the occupation time. CONCLUSIONS: The results of this study revealed that the overall fungal diversity in the closed habitat changed during human presence; therefore, it is crucial to properly maintain a closed habitat to preserve it from deteriorating and keep it safe for its inhabitants. Differences in community profiles were observed when statistically treated, especially of the mycobiome of samples collected at day 20. On a genus level Epiccocum, Alternaria, Pleosporales, Davidiella, and Cryptococcus showed increased abundance over the occupation time.


Asunto(s)
Hongos/fisiología , Marte , Luna , Micobioma/fisiología , Simulación del Espacio , ADN de Hongos , Hongos/clasificación , Hongos/genética , Variación Genética , Humanos , Micobioma/genética , ARN de Hongos , Análisis de Secuencia de ADN
11.
Nervenarzt ; 88(9): 1003-1009, 2017 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-28188402

RESUMEN

Data regarding the incidence and prevalence of epileptic seizures in Alzheimer's disease show great variability and are clinically underestimated due to their atypical symptomatology. Considering their considerable negative effects on cognition and activities of daily living, epileptic seizures need to be correctly treated. Hypotheses with respect to the pathogenetic mechanisms and associations between Alzheimer's disease and epilepsy are mostly derived from animal experiments. The causal connections are so far insufficiently understood. Data on risk factors are inconsistent due to methodological limitations in studies. Clinical data for these indications show good response to therapy with anticonvulsants and good tolerability in the case of new active substances. When treating epileptic seizures in this patient collective using anticonvulsants, potential adverse effects and possible drug interactions need to be closely monitored.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Convulsiones/diagnóstico , Anciano , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/epidemiología , Anticonvulsivantes/efectos adversos , Anticonvulsivantes/uso terapéutico , Comorbilidad , Estudios Transversales , Diagnóstico Diferencial , Interacciones Farmacológicas , Electroencefalografía/efectos de los fármacos , Humanos , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Riesgo , Convulsiones/tratamiento farmacológico , Convulsiones/epidemiología
12.
Vox Sang ; 111(4): 350-356, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27432635

RESUMEN

BACKGROUND: A 100% apheresis platelet supply is considered to increase transfusion safety by lowering donor exposures for transfusion recipients. We performed a risk benefit analysis to contrast the reduction of donor exposures and the risk of contaminated blood products in the nation-wide inventory with the donor risks associated with a switch to a 100% apheresis platelet supply in Germany. METHODS: Donor exposures and the number of contaminated blood products resulting from HIV-like, HBV-like, HCV-like pathogens and two theoretical agents with infection rates of 10 and 1000 in 100 000, respectively, were calculated for a 100% apheresis platelet supply in Germany based on the 2006-2012 hemovigilance reports. These numbers were compared with the current mixed platelet supply of pooled and apheresis platelets. Moreover, additional donation time and apheresis donor complications resulting from a 100% apheresis platelet supply were estimated. RESULTS: Per million total blood products (red cells, platelets, fresh frozen plasma), a 100% apheresis platelet supply would reduce donor exposures by 87 100 and the number of contaminated blood products ranging from 0·8 to 871·1. On the other hand, this requires additional 29 478 apheresis donations, 3·4 years additional donor time, and would be associated with 58 additional donor complications, respectively. CONCLUSIONS: A 100% apheresis platelet supply would reduce donor exposures and the number of contaminated blood products in the inventory, but would increase apheresis complications in donors. Potential risks for patients must be carefully weighed against the risks for donors, dependent on the specific pathogen scenario.


Asunto(s)
Seguridad de la Sangre , Plaquetoferesis , Donantes de Sangre , Plaquetas/fisiología , Humanos , Transfusión de Plaquetas/efectos adversos , Medición de Riesgo
13.
Brain Stimul ; 9(3): 356-363, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27033012

RESUMEN

BACKGROUND: Various brain stimulation techniques are in use to treat epilepsy. These methods usually require surgical implantation procedures. Transcutaneous vagus nerve stimulation (tVNS) is a non-invasive technique to stimulate the left auricular branch of the vagus nerve at the ear conch. OBJECTIVE: We performed a randomized, double-blind controlled trial (cMPsE02) to assess efficacy and safety of tVNS vs. control stimulation in patients with drug-resistant epilepsy. METHODS: Primary objective was to demonstrate superiority of add-on therapy with tVNS (stimulation frequency 25 Hz, n = 39) versus active control (1 Hz, n = 37) in reducing seizure frequency over 20 weeks. Secondary objectives comprised reduction in seizure frequency from baseline to end of treatment, subgroup analyses and safety evaluation. RESULTS: Treatment adherence was 84% in the 1 Hz group and 88% in the 25 Hz group, respectively. Stimulation intensity significantly differed between the 1 Hz group (1.02 ± 0.83 mA) and the 25 Hz group (0.50 ± 0.47 mA; p = 0.006). Mean seizure reduction per 28 days at end of treatment was -2.9% in the 1 Hz group and 23.4% in the 25 Hz group (p = 0.146). In contrast to controls, we found a significant reduction in seizure frequency in patients of the 25 Hz group who completed the full treatment period (20 weeks; n = 26, 34.2%, p = 0.034). Responder rates (25%, 50%) were similar in both groups. Subgroup analyses for seizure type and baseline seizure frequency revealed no significant differences. Adverse events were usually mild or moderate and comprised headache, ear pain, application site erythema, vertigo, fatigue, and nausea. Four serious adverse events were reported including one sudden unexplained death in epilepsy patients (SUDEP) in the 1 Hz group which was assessed as not treatment-related. CONCLUSIONS: tVNS had a high treatment adherence and was well tolerated. Superiority of 25 Hz tVNS over 1 Hz tVNS could not be proven in this relatively small study, which might be attributed to the higher stimulation intensity in the control group. Efficacy data revealed results that justify further trials with larger patient numbers and longer observation periods.


Asunto(s)
Epilepsia Refractaria/diagnóstico , Epilepsia Refractaria/terapia , Estimulación Eléctrica Transcutánea del Nervio/métodos , Estimulación del Nervio Vago/métodos , Adulto , Método Doble Ciego , Epilepsia Refractaria/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento , Nervio Vago/fisiología
14.
Nanotechnology ; 27(13): 135202, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-26901846

RESUMEN

Molybdenum rhenium alloy thin films can exhibit superconductivity up to critical temperatures of T(c)=15K. At the same time, the films are highly stable in the high-temperature methane/hydrogen atmosphere typically required to grow single wall carbon nanotubes. We characterize molybdenum rhenium alloy films deposited via simultaneous sputtering from two sources, with respect to their composition as function of sputter parameters and their electronic dc as well as GHz properties at low temperature. Specific emphasis is placed on the effect of the carbon nanotube growth conditions on the film. Superconducting coplanar waveguide resonators are defined lithographically; we demonstrate that the resonators remain functional when undergoing nanotube growth conditions, and characterize their properties as function of temperature. This paves the way for ultra-clean nanotube devices grown in situ onto superconducting coplanar waveguide circuit elements.

15.
Phys Chem Chem Phys ; 18(4): 3056-64, 2016 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-26739498

RESUMEN

In this contribution, we investigate the insertion of sodium into tetracyanoquinodimethane (TCNQ) and its effect on the electronic structure by means of a surface science experiment. We exposed a TCNQ thin film stepwise to sodium vapour and monitored the electronic structure by X-ray photoelectron spectroscopy (XPS) and ultra-violet photoelectron spectroscopy (UPS). During the insertion experiment three stages were observed, which can be related to three different phases, predominantly consisting of TCNQ(0), TCNQ(1-) and TCNQ(2-). With increasing sodium content the Fermi level shifts upwards and new electronic states appear in the band gap. For phases with high sodium content the sodium diffusion seems to be inhibited which we attribute to closed diffusion pathways in the molecular structure of TCNQ(1-).

16.
Eur J Pain ; 20(5): 701-10, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26516705

RESUMEN

BACKGROUND: Kinesiophobia is an excessive, irrational and debilitating fear of physical movement and activity resulting from a feeling of vulnerability to painful injury or re-injury. The Tampa Scale for kinesiophobia (TSK) is a patient-reported outcome (PRO) measure designed to help identify kinesiophobia. The original version of the TSK had 17 items. A 13-item version was later found to have better psychometric properties and was used in the present study. Although the TSK-13 has been widely studied, one shortcoming is the lack of clinically meaningful score categories. The objective of the present study was to develop severity levels to help aid clinical interpretation of TSK-13 scores. METHODS: After creating four proposed TSK-13 severity ranges, a sample of chronic musculoskeletal pain disorder (CMPD) patients (N = 912) was grouped by TSK-13 scores into: Subclinical (score = 13-22, n = 100; 11%), mild (23-32, n = 271; 30%), moderate (33-42, n = 385; 42%) and severe (43-52, n = 156; 17%) levels of kinesiophobia. These severity groups were then validated by their associations with objective lifting performance (presumed to be highly related to one's level of kinesiophobia) and other PRO questionnaires, assessing depressive symptoms, pain intensity, pain-related anxiety and perceived disability, which all have been shown in previous research to be associated with TSK scores. RESULTS: The TSK-13 severity level groups were significantly associated with all lifting performance and PRO variables (p < 0.001). As TSK-13 severity levels increased, lifting performance decreased, while pain intensity, depressive symptoms, pain-related anxiety and perceived disability increased. CONCLUSIONS: TSK-13 severity levels were strongly associated with objective lifting performance variables and psychosocial PRO measures, providing support for these severity levels as a guideline for healthcare providers and researchers in interpreting TSK-13 scores.


Asunto(s)
Dolor Crónico/psicología , Ejercicio Físico , Movimiento , Dolor Musculoesquelético/psicología , Trastornos Fóbicos/psicología , Adulto , Miedo/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos Fóbicos/diagnóstico , Psicometría , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios
18.
Phys Rev Lett ; 113(18): 186802, 2014 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-25396386

RESUMEN

The density of states ϱ(E) of graphene is investigated numerically and within the self-consistent T-matrix approximation in the presence of vacancies within the tight binding model. The focus is on compensated disorder, where the concentration of vacancies n(A) and n(B) in both sublattices is the same. Formally, this model belongs to the chiral symmetry class BDI. The onlinear sigma model predicts for BDI a Gade-type singularity ϱ(E)∼|E|(-1)exp[-|log(E)|(-1/x)]. Our numerical data are comparable to this result in a preasymptotic regime that gives way, however, at even lower energies to ϱ(E)∼E(-1)|log(E)|(-x̃), 1≤x̃<2. We take this finding as evidence that, similar to the case of dirty d-wave superconductors, generic bipartite random hopping models may also exhibit unconventional (strong-coupling) fixed points for certain kinds of randomly placed scatterers if these are strong enough. Our research suggests that graphene with (effective) vacancy disorder is a physical representative of such systems.

19.
J Vet Pharmacol Ther ; 36(6): 617-20, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23682764

RESUMEN

A risk assessment conducted in 2007 identified significant knowledge gaps about tissue residues of melamine and related triazine analogs such as cyanuric acid in animals that had eaten contaminated food. The USFDA subsequently designed studies to determine residue levels in muscle, serum, and kidneys of catfish and trout given a single gavage dose of 20 mg/kg body weight (BW) of melamine, cyanuric acid, or 20 mg/kg BW of both compounds simultaneously. Renal triazines were determined by LC-MS/MS at postdose days 1, 3, 7, 14, 28 (and day 42 for trout). When dosed individually, melamine and cyanuric acid kidney residues depleted much faster than those in fish given both compounds together. Combined dose residue depletion was punctuated by extreme outliers due to the formation of persistent renal melamine cyanurate crystals.


Asunto(s)
Ictaluridae , Oncorhynchus mykiss , Triazinas/farmacocinética , Animales , Residuos de Medicamentos , Riñón/metabolismo , Triazinas/metabolismo
20.
Nanotechnology ; 22(44): 445401, 2011 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-21983364

RESUMEN

Single nanowire radial junction solar cell devices were fabricated using Si nanowires synthesized by Al-catalyzed vapor-liquid-solid growth of the p(+) core (Al auto-doping) and thin film deposition of the n(+)-shell at temperatures below 650 °C. Short circuit current densities of 11.7 mA cm(-2) were measured under 1-sun AM1.5G illumination, showing enhanced optical absorption. The power conversion efficiencies were limited to < 1% by the low open circuit voltage and fill factor of the devices, which was attributed to junction shunt leakage promoted by the high p(+)/n(+) doping. This demonstration of a radial junction device represents an important advance in the use of Al-catalyzed Si nanowire growth for low cost photovoltaics.

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