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1.
J Occup Health Psychol ; 26(4): 304-325, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33998817

RESUMEN

This article builds on earlier research on work events and uses a recently developed taxonomy of situation perceptions-the CAPTION taxonomy-to study daily work events. The authors specifically test the ideas that the specific affective event dimensions A (Adversity) and O (humOr), and cognitive and typicality dimensions-I (Importance), C (Complexity), and T (Typicality)-contribute to explaining daily well-being beyond P (Positive valence) and N (Negative valence). Study 1 included N = 242 employees who filled in a diary over 5 workdays, and Study 2 included a total of 295 employees in an experience sampling design. Results from multilevel confirmatory factor analyses with events nested in persons and days nested in persons suggested that a seven-dimension model-in line with the CAPTION taxonomy-improved model fit. Multilevel structural equation modeling further revealed that the additional dimensions contributed to explaining well-being after work (Study 1) and well-being at work (Study 2) at both the between- and the within-person level. These effects were in particular driven by the A (Adversity) and O (humOr) dimensions. The authors discuss to what degree a multidimensional perspective on situation perceptions can improve occupational health researchers' understanding of work events as drivers of well-being at work. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Asunto(s)
Evaluación Ecológica Momentánea , Humanos , Análisis Multinivel
2.
Phys Rev Lett ; 123(23): 231106, 2019 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-31868502

RESUMEN

Dual-phase xenon detectors lead the search for keV-scale nuclear recoil signals expected from the scattering of weakly interacting massive particle (WIMP) dark matter, and can potentially be used to study the coherent nuclear scattering of MeV-scale neutrinos. New capabilities of such experiments can be enabled by extending their nuclear recoil searches down to the lowest measurable energy. The response of the liquid xenon target medium to nuclear recoils, however, is not well characterized below a few keV, leading to large uncertainties in projected sensitivities. In this work, we report a new measurement of ionization signals from nuclear recoils in liquid xenon down to the lowest energy reported to date. At 0.3 keV, we find that the average recoil produces approximately one ionization electron; this is the first measurement of nuclear recoil signals at the single-ionization-electron level, approaching the physical limit of liquid xenon ionization detectors. We discuss the implications of these measurements on the physics reach of xenon detectors for nuclear-recoil-based WIMP dark matter searches and the detection of coherent elastic neutrino-nucleus scattering.

3.
Brain Stimul ; 12(5): 1111-1120, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31031208

RESUMEN

BACKGROUND: Data on pediatric DBS is still limited because of small numbers in single center series and lack of systematic multi-center trials. OBJECTIVES: We evaluate short- and long-term adverse events (AEs) of patients undergoing deep brain stimulation (DBS) during childhood and adolescence. METHODS: Data collected by the German registry on pediatric DBS (GEPESTIM) were analyzed according to reversible and irreversible AEs and time of occurrence with relation to DBS-surgery: Intraoperative, perioperative (<4 weeks), postoperative (4 weeks < 6 months) and long term AEs (>6 months). RESULTS: 72 patients with childhood-onset dystonia from 10 DBS-centers, who received 173 DBS electrodes and 141 implantable pulse generators (IPG), were included in the registry. Mean time of postoperative follow-up was 4.6 ±â€¯4 years. In total, 184 AEs were documented in 53 patients (73.6%). 52 DBS-related AEs in 26 patients (36.1%) required 45 subsequent surgical interventions 4.7 ±â€¯4.1 years (range 3 months-15 years) after initial implantation. The total risk of an AE requiring surgical intervention was 7.9% per electrode-year. Hardware-related AEs were the most common reason for surgery. There was a tendency of a higher rate of AEs in patients aged 7-9 years beyond 6 months after implantation. DISCUSSION: The intraoperative risk of AEs in pediatric patients with dystonia undergoing DBS is very low, whereas the rate of postoperative hardware-related AEs is a prominent feature with a higher occurrence compared to adults, especially on long-term follow-up. CONCLUSION: Factors leading to such AEs must be identified and patient management has to be focused on risk minimization strategies in order to improve DBS therapy and maximize outcome in pediatric patients.


Asunto(s)
Estimulación Encefálica Profunda/efectos adversos , Trastornos Distónicos/epidemiología , Trastornos Distónicos/terapia , Electrodos Implantados/efectos adversos , Adolescente , Niño , Trastornos Distónicos/diagnóstico , Femenino , Estudios de Seguimiento , Alemania/epidemiología , Humanos , Masculino , Infección de la Herida Quirúrgica/diagnóstico , Infección de la Herida Quirúrgica/epidemiología
4.
Psychol Assess ; 31(7): 939-951, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30896213

RESUMEN

Psychologists have long been interested in studying individual differences in implicit motives. Implicit motives are typically measured asking respondents to write fantasy-stories based on a series of pictures showing one or several persons. The stories are then coded for implicit motivational content by trained experts because researchers have long assumed that respondents have no conscious access to the motivational themes in the stories they write. However, empirical research on self-evaluation of implicit motives is scarce. In this article, we provide new insights into this topic with a new measurement procedure-the motive self-categorization (MSC) test. In the MSC, respondents first fill out an implicit motive measure and then self-code their stories using lists of picture-specific statements that are typical concrete manifestations of implicit motives in the specific picture. We studied the MSC in a sample of 247 respondents by analyzing convergence with expert codings using a latent multitrait-multimethod item response theory (IRT) model. Results showed respondents could evaluate the motivational content of their stories (latent motive-motive rs = .37-.62), IRT latent motive scores based on self-categorization showed evidence of reliability (rs = .42-.67), and we found small method effects. The discussion focuses on implications for theory on measuring implicit motives and the possibility that self-insight occasionally goes beyond expert insight. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Asunto(s)
Motivación , Inventario de Personalidad/estadística & datos numéricos , Personalidad/fisiología , Reconocimiento en Psicología/fisiología , Autoevaluación (Psicología) , Pensamiento/fisiología , Bélgica , Femenino , Humanos , Reproducibilidad de los Resultados
5.
Eur Radiol ; 29(9): 5063-5072, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30796575

RESUMEN

OBJECTIVES: To compare Gd-EOB-DTPA dynamic hepatocyte-specific contrast-enhanced MRI (DHCE-MRI) with 99mTc-mebrofenin hepatobiliary scintigraphy (HBS) as quantitative liver function tests for the preoperative assessment of patients undergoing liver resection. METHODS: Patients undergoing liver surgery and preoperative assessment of future remnant liver (FRL) function using 99mTc-mebrofenin HBS were included. Patients underwent DHCE-MRI. Total liver uptake function was calculated for both modalities: mebrofenin uptake rate (MUR) and Ki respectively. The FRL was delineated with both SPECT-CT and MRI to calculate the functional share. Blood samples were taken to assess biochemical liver parameters. RESULTS: A total of 20 patients were included. The HBS-derived MUR and the DHCE-MRI-derived mean Ki correlated strongly for both total and FRL function (Pearson r = 0.70, p = 0.001 and r = 0.89, p < 0.001 respectively). There was a strong agreement between the functional share determined with both modalities (ICC = 0.944, 95% CI 0.863-0.978, n = 20). There was a significant negative correlation between liver aminotransferases and bilirubin for both MUR and Ki. CONCLUSIONS: Assessment of liver function with DHCE-MRI is comparable with that of 99mTc-mebrofenin HBS and has the potential to be combined with diagnostic MRI imaging. This can therefore provide a one-stop-shop modality for the preoperative assessment of patients undergoing liver surgery. KEY POINTS: • Quantitative assessment of liver function using hepatobiliary scintigraphy is performed in the preoperative assessment of patients undergoing liver surgery in order to prevent posthepatectomy liver failure. • Gd-EOB-DTPA dynamic hepatocyte-specific contrast-enhanced MRI (DHCE-MRI) is an emerging method to quantify liver function and can serve as a potential alternative to hepatobiliary scintigraphy. • Assessment of liver function with dynamic gadoxetate-enhanced MRI is comparable with that of hepatobiliary scintigraphy and has the potential to be combined with diagnostic MRI imaging.


Asunto(s)
Gadolinio DTPA/farmacología , Hepatopatías/diagnóstico , Hígado/diagnóstico por imagen , Cintigrafía/métodos , Tomografía Computarizada de Emisión de Fotón Único/métodos , Anciano , Femenino , Hepatectomía , Humanos , Hepatopatías/cirugía , Pruebas de Función Hepática/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Radiofármacos/farmacología
6.
J Pers Assess ; 101(4): 414-424, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29388822

RESUMEN

Researchers have long been interested in studying differences in implicit motive between different groups. Implicit motives are typically measured by scoring text that respondents have written in response to picture cues. Recently, research on the measurement of implicit motives has made progress through the application of a dynamic Thurstonian item-response theory model (DTM; Lang, 2014 ) that captures 2 basic motivational processes in motivational research: motive competition and dynamic reduction of motive strength after a motive has been acted out. In this article, the authors use the DTM to investigate differential item functioning (DIF) in implicit motive measures. The article first discusses DIF in the context of the DTM. The authors then conduct a DIF analysis of data from a study that used a picture set of the Operant Motive Test (OMT; Kuhl & Scheffer, 2002) with participants from Cameroon, Germany, and Costa Rica. Results showed no evidence of DIF in 9 pictures and some evidence for DIF in 3 pictures. The authors show a partial invariance model can be specified and use this partial invariance model to study latent mean differences between Cameroon, Germany, and Costa Rica. The discussion focuses on the use of IRT DIF methods in future research on implicit motives.


Asunto(s)
Estado de Salud , Motivación , Satisfacción Personal , Adulto , Camerún , Costa Rica , Femenino , Alemania , Humanos , Masculino
7.
Chaos ; 28(7): 075310, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30070533

RESUMEN

Causal network reconstruction from time series is an emerging topic in many fields of science. Beyond inferring directionality between two time series, the goal of causal network reconstruction or causal discovery is to distinguish direct from indirect dependencies and common drivers among multiple time series. Here, the problem of inferring causal networks including time lags from multivariate time series is recapitulated from the underlying causal assumptions to practical estimation problems. Each aspect is illustrated with simple examples including unobserved variables, sampling issues, determinism, stationarity, nonlinearity, measurement error, and significance testing. The effects of dynamical noise, autocorrelation, and high dimensionality are highlighted in comparison studies of common causal reconstruction methods. Finally, method performance evaluation approaches and criteria are suggested. The article is intended to briefly review and accessibly illustrate the foundations and practical problems of time series-based causal discovery and stimulate further methodological developments.

8.
NMR Biomed ; 31(10): e3932, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29846986

RESUMEN

This review on magnetic resonance elastography (MRE) of the breast provides an overview of available literature and describes current developments in the field of breast MRE, including new transducer technology for data acquisition and multi-frequency-derived power-law behaviour of tissue. Moreover, we discuss the future potential of breast MRE, which goes beyond its original application as an additional tool in differentiating benign from malignant breast lesions. These areas of ongoing and future research include MRE for pre-operative tumour delineation, staging, monitoring and predicting response to treatment, as well as prediction of the metastatic potential of primary tumours.


Asunto(s)
Mama/diagnóstico por imagen , Diagnóstico por Imagen de Elasticidad , Imagen por Resonancia Magnética , Módulo de Elasticidad , Humanos , Publicaciones
9.
J Vet Intern Med ; 32(1): 99-106, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29280194

RESUMEN

BACKGROUND: Prophylactic administration of calcitriol has been suggested to mitigate the risk of hypocalcemia after parathyroidectomy. The effect of calcitriol on postoperative serum ionized calcium concentrations has not been evaluated in dogs after parathyroidectomy. HYPOTHESIS/OBJECTIVES: To determine the effect of prophylactic calcitriol administration on postoperative serum ionized calcium (iCa) concentrations in dogs with primary hyperthyroidism (PHPTH) treated by parathyroidectomy. ANIMALS: Seventy-eight dogs with primary hyperparathyroidism treated surgically. METHODS: Multi-institutional retrospective case study. Medical records from 2005 to 2015 were evaluated. Dogs were included if they had a diagnosis of PHPTH and had surgery to remove parathyroid tissue. Serum iCa concentrations were monitored for a minimum of 2 days postoperatively. Two study groups were evaluated: calcitriol administration and no calcitriol administration. RESULTS: Serial postoperative iCa concentrations measured at 12-hour time intervals for 2 days postoperatively were positively associated with preoperative iCa concentrations. This association was evident at each time interval, and the effect of preoperative iCa concentrations on postoperative iCa concentrations decreased as time elapsed (12 hours, P < 0.0001; 24 hours, P < 0.0001; 36 hours, P < 0.04; and 48 hours, P = 0.01). Prophylactic calcitriol administration was not found to be significantly associated with postoperative iCa concentrations or its rate of decrease after parathyroidectomy. CONCLUSION AND CLINICAL IMPORTANCE: We found no protective value in administering calcitriol prophylactically to prevent hypocalcemia in the immediate postoperative period (48 hours) after parathyroidectomy. Preoperative iCa concentrations had a significant positive association with postoperative iCa concentrations throughout the monitoring period.


Asunto(s)
Calcitriol/uso terapéutico , Calcio/sangre , Enfermedades de los Perros/sangre , Paratiroidectomía/veterinaria , Animales , Estudios de Casos y Controles , Enfermedades de los Perros/cirugía , Perros , Femenino , Hiperparatiroidismo Primario/cirugía , Hiperparatiroidismo Primario/veterinaria , Hipocalcemia/veterinaria , Masculino , Paratiroidectomía/efectos adversos , Estudios Retrospectivos
10.
Ned Tijdschr Geneeskd ; 160: D337, 2016.
Artículo en Holandés | MEDLINE | ID: mdl-27531248

RESUMEN

Five years ago, we reported on the use of 1H-magnetic resonance spectroscopy (MRS-PDFF) as a non-invasive means of determining the amount of liver fat. Liver biopsy, the current reference method, has several shortcomings (e.g. risk of complications and large interobserver variability), which are less pronounced or absent in MRS-PDFF. In RCT's, MRS-PDFF is currently used as an outcome measure to assess therapy response. Its successor is already being deployed: MRI-PDFF. This is a short whole-liver MRI scan, which takes approximately 18 seconds. The use of MRS- or MRI-PDFF has not boomed in the Netherlands. Reasons include unfamiliarity with the technique amongst both clinicians and radiologists, as well as increased reliance on ultrasound imaging with Fibroscan by hepatologists in particular. This latter method, however, is less accurate in classifying the various steatosis grades than MRS- and MRI-PDFF.


Asunto(s)
Hígado Graso/diagnóstico por imagen , Hígado/diagnóstico por imagen , Espectroscopía de Resonancia Magnética/métodos , Biopsia , Hígado Graso/patología , Humanos , Países Bajos
11.
Oral Dis ; 20(3): e120-7, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24006964

RESUMEN

OBJECTIVES: Early detection of oral cancer is a major health issue. The objective of this pilot study was to analyze the deformability of healthy and cancer cells using a microfluidic optical stretcher (OS). MATERIAL AND METHODS: Different cancer cell lines, primary oral cancer cells, and their healthy counterparts were cultivated and characterized, respectively. A measurable deformation of the cells along the optical axis was detected, caused by surface stress, which is optically induced by the laser power. RESULTS: All cells revealed a viscoelastic extension behavior and showed a characteristic deformation response under laser light exposure. The CAL-27/-33 cells exhibited the highest relative deformation. All other cells achieved similar values, but on a lower level. The cytoskeleton reacts sensitively of changing environmental conditions, which may be influenced by growth behavior of the cancer specimens. Nevertheless, the statistical analysis showed significant differences between healthy and cancer cells. CONCLUSION: Generally, malignant and benign cells showed significantly different mechanical behavior. Cancer-related changes influence the composition of the cytoskeleton and thus affect the deformability, but this effect may be superimposed by cell cultivation conditions or cell doubling time. These influences had to be substituted by brush biopsies to minimize confounders in pursuing investigations.


Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias de la Boca/patología , Adulto , Anciano , Fenómenos Biomecánicos , Técnicas Citológicas , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Células Tumorales Cultivadas
12.
Artículo en Inglés | MEDLINE | ID: mdl-24329318

RESUMEN

Complex network theory provides a powerful toolbox for studying the structure of statistical interrelationships between multiple time series in various scientific disciplines. In this work, we apply the recently proposed climate network approach for characterizing the evolving correlation structure of the Earth's climate system based on reanalysis data for surface air temperatures. We provide a detailed study of the temporal variability of several global climate network characteristics. Based on a simple conceptual view of red climate networks (i.e., networks with a comparably low number of edges), we give a thorough interpretation of our evolving climate network characteristics, which allows a functional discrimination between recently recognized different types of El Niño episodes. Our analysis provides deep insights into the Earth's climate system, particularly its global response to strong volcanic eruptions and large-scale impacts of different phases of the El Niño Southern Oscillation.

13.
J Small Anim Pract ; 51(5): 264-9, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20536696

RESUMEN

OBJECTIVE: To determine if age, breed, gender, weight or distraction index (DI) influenced the risk of radiographic osteoarthritis (OA) of canine hip dysplasia (CHD) in four common dog breeds; the American bulldog, Bernese mountain dog, Newfoundland and standard poodle. MATERIALS AND METHODS: This was a cross sectional prevalence study with 4349 dogs. Canine hips were evaluated using 3 radiographic projections: the hip-extended view, the compression view and the distraction view. The hip-extended view was examined for the presence of OA. The PennHIP distraction view was utilized to calculate the DI. For all breeds, a multiple logistic regression model incorporating age, weight, gender, and DI was created. For each breed, disease-susceptibility curves grouping dogs on the basis of age were constructed. Receiver-operating characteristic (ROC) curves were developed for each breed regardless of age. RESULTS: For all breeds, DI was the most significant risk factor for the development of OA associated with CHD. Weight and age were also significant risk factors in all four breeds, but gender was not. CLINICAL SIGNIFICANCE: Results from this study support previous findings, that irrespective of breed, the probability of radiographic OA increases with hip joint laxity as measured by the DI. Breed-specific differences in this relationship, however, warrant investigation of all breeds affected by CHD to determine inherent dependency of hip OA on joint laxity. Such findings guide veterinarians in helping dog breeders to make evidence-based breeding decisions and in informing dog owners to implement preventative treatments for CHD for dogs found to be at risk.


Asunto(s)
Displasia Pélvica Canina/complicaciones , Inestabilidad de la Articulación/veterinaria , Osteoartritis de la Cadera/veterinaria , Factores de Edad , Animales , Peso Corporal , Estudios Transversales , Perros , Femenino , Inestabilidad de la Articulación/complicaciones , Modelos Logísticos , Masculino , Osteoartritis de la Cadera/etiología , Curva ROC , Factores de Riesgo , Factores Sexuales , Especificidad de la Especie
15.
Sportverletz Sportschaden ; 15(2): 40-4, 2001 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-11475620

RESUMEN

Specific footwear has been developed for different, partly newly developed mountain sports. This footwear has very different basic characteristics. This experimental study is dealing with the dynamic parameters of electronic plantar pressure measurements in normal walking using different mountain sport shoes designed for a special purpose in mountaineering. These mountain shoes included a hiking shoe, a trekking shoe and a high-alpine shoe which can take crampons. The electronic plantar pressure measurements were done with the Parotec system of the company Paromed with insoles with hydrocell-sensors. The data obtained during the study were proceeded through a variant analysis. There were no significant differences for impulse and contact time, nevertheless concerning maximal pressure there were significant differences between walking barefoot and walking with the hiking and high-alpine shoe. Even when walking in different mountain shoes the feet conserve their own characteristics and their walking style. The different mountain shoes did not alter most of the measured plantar parameters significantly comparing barefoot walking to walking with the different mountain shoes or comparing walking in the different mountain shoes.


Asunto(s)
Pie/fisiología , Zapatos/clasificación , Soporte de Peso/fisiología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Procesamiento de Señales Asistido por Computador , Transductores de Presión
20.
Acad Emerg Med ; 6(12): 1203-9, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10609921

RESUMEN

UNLABELLED: In the clinical trial of diaspirin cross-linked hemoglobin (DCLHb), optimal therapy required the immediate enrollment of patients with severe, uncompensated, traumatic hemorrhagic shock. When it was not feasible to obtain prospective consent, an exception to informed consent was used according to FDA regulation 21 CFR 50.24. OBJECTIVES: To examine the informed consent process and the use of the consent exception and consent to continue (CTC), and to describe the patients for whom this process was used. METHODS: This was a multicenter, randomized, controlled, single-blinded efficacy trial of DCLHb as an adjunct to standard therapy in the treatment of severe, traumatic hemorrhagic shock. Patients with unstable vital signs or a critical base deficit were treated, with a primary study endpoint of 28-day mortality. RESULTS: During the 11-month study period, 112 patients were randomized in 18 U.S. trauma centers, and data from 98 of the infused patients were analyzed. Prospective consent was obtained from two patients, three family members, and one legally authorized representative (LAR) (6%). Consent to continue was requested for 89 patients (89%), and full participation was granted for 87 of these patients (98%). Consent to continue was provided by 54 (98%) of the 55 patients approached. The mean number of days for family/LAR CTC was 1.1 +/-3.8 days, and 50% of the time it was obtained on the day of study enrollment. Patient CTC was obtained in an average of 13 +/- 23 days, with a median of four days. Patients treated in this protocol were more likely to have sustained penetrating trauma than the overall trauma patient population treated in these trauma centers (44% vs 21%, p = 0.002). CONCLUSIONS: Informed consent in this study of an emergent therapy most often involved the use of the consent exception and consent to continue, the latter of which occurred in a timely manner. Nearly all of those who were approached for CTC approved full participation in the study, suggesting acceptance of the process outlined in the new regulations. Patients treated in a hemorrhagic shock clinical trial may differ from the general trauma patient population.


Asunto(s)
Ensayos Clínicos como Asunto/legislación & jurisprudencia , Ensayos Clínicos como Asunto/normas , Consentimiento Informado/legislación & jurisprudencia , Choque Hemorrágico/tratamiento farmacológico , Heridas y Lesiones/complicaciones , Adulto , Aspirina/administración & dosificación , Aspirina/análogos & derivados , Distribución de Chi-Cuadrado , Femenino , Hemoglobinas/administración & dosificación , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Cooperación del Paciente , Valores de Referencia , Reproducibilidad de los Resultados , Choque Hemorrágico/etiología , Choque Hemorrágico/mortalidad , Análisis de Supervivencia , Centros Traumatológicos , Estados Unidos
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