El viaje desde los cuestionarios Likert a los cuestionarios de elección forzosa: evidencia de la invarianza de los parámetros de los ítems

Multidimensional forced-choice questionnaires are widely regarded in the personnel selection literature for their ability to control response biases. Recently developed IRT models usually rely on the assumption that item parameters remain invariant when they are paired in forced-choice blocks, without giving it much consideration. This study aims to test this assumption empirically on the MUPP-2PL model, comparing the parameter estimates of the forced-choice format to their graded-scale equivalent on a Big Five personality instrument. The assumption was found to hold reasonably well, especially for the discrimination parameters. In the cases in which it was violated, we briefly discuss the likely factors that may lead to non-invariance. We conclude discussing the practical implications of the results and providing a few guidelines for the design of forced-choice questionnaires based on the invariance assumptionLos cuestionarios de elección forzosa multidimensionales son bastante apreciados en la literatura de selección de personal por su capacidad para controlar los sesgos de respuesta. Los modelos de TRI desarrollados recientemente normalmente asumen que los parámetros de los ítems permanecen invariantes cuando se emparejan en bloques de elección forzosa, sin dedicarle mucha atención. Este estudio tiene como objetivo poner a prueba empíricamente este supuesto en el modelo MUPP-2PL, comparando las estimaciones de los parámetros del formato de elección forzosa con su equivalente en escala graduada, en un instrumento de personalidad Big Five. Se encontró que el supuesto se cumplía razonablemente bien, especialmente para los parámetros de discriminación. En los casos en los que no se cumplió se discuten brevemente los posibles factores que pueden dar lugar a no invarianza. Concluimos discutiendo las implicaciones prácticas de los resultados y proponiendo algunas pautas para el diseño de cuestionarios de elección forzosa basados en el supuesto de invarianzaThis research is funded by the Spanish government’s Ministerio de Economia y Competitividad, projects PSI 2015-65557-P and PSI 2017-85022-

Lebensqualität und alexithyme Merkmale bei Patienten mit somatoformer Schmerzstörung

Zusammenfassung: Hintergrund: Patienten mit einer somatoformen Schmerzstörung weisen häufig eine schlechte gesundheitsbezogene Lebensqualität (QoL) und Schwierigkeiten in der Affektregulation (Alexithymie) auf. Ziel dieser Studie war es, den Zusammenhang zwischen QoL und alexithymen Merkmalen zu untersuchen. Patienten und Methoden: Bei 51Patienten mit somatoformer Schmerzstörung (durchschnittliche Erkrankungsdauer: 11,6Jahre) wurden Alexithymie (TAS-20), QoL (WHOQOL-BREF), psychische Belastung und Somatisierung (SCL-90-R) und depressive Symptome (MADRS) erhoben. Ergebnisse: Es fand sich eine signifikante negative Korrelation zwischen QoL und alexithymen Persönlichkeitsmerkmalen, insbesondere der psychischen QoL und dem TAS-20-Gesamtwert (r=−0,63, p<0,001). Die Alexithymiesubskala "Schwierigkeiten, Gefühle zu beschreiben" erwies sich als signifikanter Einflussfaktor für die psychische QoL (β=−0,34, p<0,01), auch nach Kontrolle von Depression, Somatisierung und Geschlecht. Schlussfolgerung: Für die insgesamt sehr niedrige QoL von Patienten mit somatoformer Schmerzstörung scheinen auch alexithyme Charakteristika eine wichtige Rolle zu spielen. Dies sollte sowohl diagnostisch als auch in der therapeutischen Zielsetzung berücksichtigt werde

Ionospheric quasi-static electric field anomalies during seismic activity in August–September 1981

The paper proposes new results, analyses and information for the plate tectonic situation in the processing of INTERCOSMOS-BULGARIA-1300 satellite data about anomalies of the quasi-static electric field in the upper ionosphere over activated earthquake source regions at different latitudes. The earthquake catalogue is made on the basis of information from the United State Geological Survey (USGS) website. The disturbances in ionospheric quasi-static electric fields are recorded by IESP-1 instrument aboard the INTERCOSMOS-BULGARIA-1300 satellite and they are compared with significant seismic events from the period 14 August–20 September 1981 in magnetically very quiet, quiet and medium quiet days. The main tectonic characteristics of the seismically activated territories are also taken in account. The main goal of the above research work is to enlarge the research of possible connections between anomalous vertical electric field penetrations into the ionosphere and the earthquake manifestations, also to propose tectonic arguments for the observed phenomena. The studies are represented in four main blocks: (i) previous studies of similar problems, (ii) selection of satellite, seismic and plate tectonic data, (iii) data processing with new specialized software and observations of the quasi-static electric field and (iiii) summary, comparison of new with previous results in our studies and conclusion. We establish the high informativity of the vertical component &lt;i&gt;Ez&lt;/i&gt; of the quasi-static electric field in the upper ionosphere according observations by INTERCOSMOS-BULGARIA-1300 that are placed above considerably activated earthquake sources. This component shows an increase of about 2–10 mV/m above sources, situated on mobile structures of the plates. The paper discusses the observed effects. It is represented also a statistical study of ionospheric effects 5–15 days before and 5–15 days after the earthquakes with magnitude M 4.8–7.9

Administration of drinking water supplement containing organic acids and medium chain fatty acids to sows significantly reduced incidence of Clostridium-associated diarrhoea in neonatal piglets: a case study

Neonatal diarrhoea in newborn piglets is an important problem in pig production that is frequently diagnosed as being the result of Clostridium perfringens infections. During parturition and in the first hours of life, the sow transmits the pathogen to its offspring. The objective of this study was to examine the possible prophylactic effect of a drinking water supplement containing organic acids and medium chain fatty acids (Selko-4-Health©), administered to sows on prevalence of neonatal diarrhoea in piglets during early lactation. The study was carried out at a farm with 1300 sows with a high incidence of neonatal diarrhoea. Gestating sows received the water supplement (0.1% per litre) daily from day 35 to end of gestation and during the lactation phase for 2 days a week

Test Results on the Silicon Pixel Detector for the TTF-FEL Beam Trajectory Monitor

Test measurements on the silicon pixel detector for the beam trajectory monitor at the free electron laser of the TESLA test facility are presented. To determine the electronic noise of detector and read-out and to calibrate the signal amplitude of different pixels the 6 keV photons of the manganese K line are used. Two different methods determine the spatial accuracy of the detector: In one setup a laser beam is focused to a straight line and moved across the pixel structure. In the other the detector is scanned using a low-intensity electron beam of an electron microscope. Both methods show that the symmetry axis of the detector defines a straight line within 0.4 microns. The sensitivity of the detector to low energy X-rays is measured using a vacuum ultraviolet beam at the synchrotron light source HASYLAB. Additionally, the electron microscope is used to study the radiation hardness of the detector.Comment: 14 pages (Latex), 13 figures (Postscript), submitted to Nuclear Instruments and Methods

Журнал кримських караїмів “Бизым йол” (“Наш шлях”) у світлі традицій караїмської преси і національної політики Кримської АРСР

В статье содержится описание караимских периодических изданий начала ХХ века, их целей и задачи, объема, основных отделов, исследуется отражение в караимской периодике процессов национального культурного ренессанса, изучается связь этнических изданий караимов с общественно-политической жизнью караимской общины.Стаття містить опис караїмських видань початку ХХ століття, з'ясовує їхні цілі і завдан-ня, обсяг, основні розділи; досліджує відбиття у караїмській періодиці процесів національного культурного ренесансу; вивчає зв'язок етнічних видань караїмів із суспільно-політичним життям караїмської громади.The article researches the Karaite mass media of the beginning of the XX century: its matters and tasks, volume, main sections, the reflection of the cultural renaissance in it and its connection with life of the Karaite community

Dissection of a metastatic gene expression signature into distinct components

BACKGROUND: Metastasis, the process whereby cancer cells spread, is in part caused by an incompletely understood interplay between cancer cells and the surrounding stroma. Gene expression studies typically analyze samples containing tumor cells and stroma. Samples with less than 50% tumor cells are generally excluded, thereby reducing the number of patients that can benefit from clinically relevant signatures. RESULTS: For a head-neck squamous cell carcinoma (HNSCC) primary tumor expression signature that predicts the presence of lymph node metastasis, we first show that reduced proportions of tumor cells results in decreased predictive accuracy. To determine the influence of stroma on the predictive signature and to investigate the interaction between tumor cells and the surrounding microenvironment, we used laser capture microdissection to divide the metastatic signature into six distinct components based on tumor versus stroma expression and on association with the metastatic phenotype. A strikingly skewed distribution of metastasis associated genes is revealed. CONCLUSION: Dissection of predictive signatures into different components has implications for design of expression signatures and for our understanding of the metastatic process. Compared to primary tumors that have not formed metastases, primary HNSCC tumors that have metastasized are characterized by predominant down-regulation of tumor cell specific genes and exclusive up-regulation of stromal cell specific genes. The skewed distribution agrees with poor signature performance on samples that contain less than 50% tumor cells. Methods for reducing tumor composition bias that lead to greater predictive accuracy and an increase in the types of samples that can be included are presented

Molecular mechanisms that distinguish TFIID housekeeping from regulatable SAGA promoters

An important distinction is frequently made between constitutively expressed housekeeping genes versus regulated genes. Although generally characterized by different DNA elements, chromatin architecture and cofactors, it is not known to what degree promoter classes strictly follow regulatability rules and which molecular mechanisms dictate such differences. We show that SAGA-dominated/wTATA-box promoters are more responsive to changes in the amount of activator, even compared to TFIID/TATA-like promoters that depend on the same activator Hsf1. Regulatability is therefore an inherent property of promoter class. Further analyses show that SAGA/TATA-box promoters are more dynamic because TATA-binding protein recruitment through SAGA is susceptible to removal by Mot1. In addition, the nucleosome configuration upon activator depletion shifts on SAGA/TATA-box promoters and seems less amenable to preinitiation complex formation. The results explain the fundamental difference between housekeeping and regulatable genes, revealing an additional facet of combinatorial control: an activator can elicit a different response dependent on core promoter class