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  1. Article: Does opportunistic testing bias cognitive performance in primates? Learning from drop-outs

    Schubiger, Michele N. / Kissling, Alexandra / Burkart, Judith M.

    PLoS ONE

    2019  Volume 14, Issue 3, Page(s) No

    Abstract: Dropouts are a common issue in cognitive tests with non-human primates. One main reason for dropouts is that researchers often face a trade-off between obtaining a sufficiently large sample size and logistic restrictions, such as limited access to ... ...

    Title translation Verzerrt opportunistisches Testen die kognitive Leistung von Primaten? Lernen von Dropouts
    Abstract Dropouts are a common issue in cognitive tests with non-human primates. One main reason for dropouts is that researchers often face a trade-off between obtaining a sufficiently large sample size and logistic restrictions, such as limited access to testing facilities. The commonly-used opportunistic testing approach deals with this trade-off by only testing those individuals who readily participate and complete the cognitive tasks within a given time frame. All other individuals are excluded from further testing and data analysis. However, it is unknown if this approach merely excludes subjects who are not consistently motivated to participate, or if these dropouts systematically differ in cognitive ability. If the latter holds, the selection bias resulting from opportunistic testing would systematically affect performance scores and thus comparisons between individuals and species. We assessed the potential effects of opportunistic testing on cognitive performance in common marmosets (Callithrix jacchus) and squirrel monkeys (Saimiri sciureus) with a test battery consisting of six cognitive tests: two inhibition tasks (Detour Reaching and A-not-B), one cognitive flexibility task (Reversal Learning), one quantity discrimination task, and two memory tasks. Importantly, we used a full testing approach in which subjects were given as much time as they required to complete each task. For each task, we then compared the performance of subjects who completed the task within the expected number of testing days with those subjects who needed more testing time. We found that the two groups did not differ in task performance, and therefore opportunistic testing would have been justified without risking biased results. If our findings generalise to other species, maximising sample sizes by only testing consistently motivated subjects will be a valid alternative whenever full testing is not feasible.
    Keywords Abbrecher (Ausbildung oder Therapie) ; Affen ; Biased Sampling ; Cognitive Ability ; Dropouts ; Fehlerhafte Stichprobenzusammenstellung ; Kognitive Fähigkeiten ; Leistung (Ausführung) ; Measurement ; Messung ; Monkeys ; Performance ; Testen ; Testing
    Language English
    Document type Article
    ZDB-ID 2267670-3
    ISSN 1932-6203
    ISSN 1932-6203
    DOI 10.1371/journal.pone.0213727
    Database PSYNDEX

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  2. Article ; Online: Informing the medical education reform in Tajikistan: evidence on the learning environment at two nursing colleges.

    Schubiger, Markus / Lechthaler, Filippo / Khamidova, Mohira / Parfitt, Barbara Ann / Prytherch, Helen / van Twillert, Erik / Wyss, Kaspar

    BMC medical education

    2019  Volume 19, Issue 1, Page(s) 85

    Abstract: Background: The Tajik medical education system is undergoing a complex reform to enhance the transition of the healthcare system from its soviet legacy of emphasizing secondary level care/specialisation to become more family medicine and primary health ... ...

    Abstract Background: The Tajik medical education system is undergoing a complex reform to enhance the transition of the healthcare system from its soviet legacy of emphasizing secondary level care/specialisation to become more family medicine and primary health care oriented. The current study presents the first empirical evaluation of the educational environment for nursing students in Tajikistan using the Dundee Ready Educational Environment Measure (DREEM). The study results contribute to the benchmarking efforts of monitoring and positively steering the educational environment over time.
    Method: The study was based on a cross-sectional survey involving 630 nursing students at two nursing colleges in Tajikistan. Students' perception of the learning environment was measured using the DREEM. Internal consistency was examined using Cronbach's alpha. General scores were calculated and measured against international benchmarks. Data was further interpreted by comparing DREEM scores between students of different sex, at different colleges and different study years using T tests.
    Results: Cronbach's alpha ranged from 0.30 to 0.75 with an overall alpha of 0.89. General DREEM scores were slightly above average compared to similar studies with nursing students in other countries. In particular, results showed that students' academic self-perception and teachers' technical competences were generally favourably rated. Teachers' pedagogical skills were critically perceived by the study participants and teaching was generally viewed as too teacher-centred with an over-emphasis on factual learning.
    Conclusions: Statistical results indicated acceptable levels of reliability of the DREEM tool when applied to the Tajik nursing educational context. Students rated the learning environment as generally satisfactory with average scores similar or slightly higher than comparable scores from similar studies involving nursing students. However, the on-going educational reform could have placed more emphasis on developing faculty pedagogical skills in nursing schools. Teaching approaches would benefit from being more competency based rather than so heavily focused on factual knowledge.
    MeSH term(s) Attitude of Health Personnel ; Competency-Based Education/statistics & numerical data ; Cross-Sectional Studies ; Education, Nursing/standards ; Educational Measurement ; Faculty, Medical/psychology ; Female ; Humans ; Learning ; Male ; Perception ; Reproducibility of Results ; Social Environment ; Students, Nursing/psychology ; Tajikistan ; Young Adult
    Language English
    Publishing date 2019-03-18
    Publishing country England
    Document type Journal Article
    ZDB-ID 2044473-4
    ISSN 1472-6920 ; 1472-6920
    ISSN (online) 1472-6920
    ISSN 1472-6920
    DOI 10.1186/s12909-019-1515-0
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: The RXR ortholog USP suppresses early metamorphic processes in Drosophila in the absence of ecdysteroids.

    Schubiger, M / Truman, J W

    Development (Cambridge, England)

    2000  Volume 127, Issue 6, Page(s) 1151–1159

    Abstract: The steroid hormone 20-hydroxyecdysone (20E) initiates metamorphosis in insects by signaling through the ecdysone receptor complex, a heterodimer of the ecdysone receptor (EcR) and ultraspiracle (USP). Analysis of usp mutant clones in the wing disc of ... ...

    Abstract The steroid hormone 20-hydroxyecdysone (20E) initiates metamorphosis in insects by signaling through the ecdysone receptor complex, a heterodimer of the ecdysone receptor (EcR) and ultraspiracle (USP). Analysis of usp mutant clones in the wing disc of Drosophila shows that in the absence of USP, early hormone responsive genes such as EcR, DHR3 and E75B fail to up-regulate in response to 20E, but other genes that are normally expressed later, such as (β)-Ftz-F1 and the Z1 isoform of the Broad-Complex (BRC-Z1), are expressed precociously. Sensory neuron formation and axonal outgrowth, two early metamorphic events, also occur prematurely. In vitro experiments with cultured wing discs showed that BRC-Z1 expression and early metamorphic development are rendered steroid-independent in the usp mutant clones. These results are consistent with a model in which these latter processes are induced by a signal arising during the middle of the last larval stage but suppressed by the unliganded EcR/USP complex. Our observations suggest that silencing by the unliganded EcR/USP receptor and the subsequent release of silencing by moderate steroid levels may play an important role in coordinating early phases of steroid driven development.
    MeSH term(s) Animals ; DNA-Binding Proteins/genetics ; Drosophila/genetics ; Drosophila/growth & development ; Drosophila/metabolism ; Drosophila Proteins ; Ecdysteroids ; Ecdysterone/pharmacology ; Female ; Gene Expression Regulation, Developmental ; Gene Targeting ; Genes, Insect ; Male ; Metamorphosis, Biological ; Models, Biological ; Neurons, Afferent/cytology ; Receptors, Steroid/genetics ; Receptors, Steroid/metabolism ; Signal Transduction ; Steroids/pharmacology ; Transcription Factors/genetics ; Up-Regulation ; Wings, Animal/growth & development
    Chemical Substances DNA-Binding Proteins ; Drosophila Proteins ; Ecdysteroids ; Receptors, Steroid ; Steroids ; Transcription Factors ; USP protein, Drosophila ; ecdysone receptor ; Ecdysterone (5289-74-7)
    Language English
    Publishing date 2000-03
    Publishing country England
    Document type Journal Article ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 90607-4
    ISSN 1477-9129 ; 0950-1991
    ISSN (online) 1477-9129
    ISSN 0950-1991
    DOI 10.1242/dev.127.6.1151
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: The three leg imaginal discs of Drosophila: "Vive la différence".

    Schubiger, Gerold / Schubiger, Margrit / Sustar, Anne

    Developmental biology

    2012  Volume 369, Issue 1, Page(s) 76–90

    Abstract: The imaginal discs of Drosophila are the larval primordia for the adult cuticular structures of the adult fly. Fate maps of different discs have been generated that show the localization of prospective adult structures. Even though the three legs differ ... ...

    Abstract The imaginal discs of Drosophila are the larval primordia for the adult cuticular structures of the adult fly. Fate maps of different discs have been generated that show the localization of prospective adult structures. Even though the three legs differ in their morphology, only the fate map for the T1 (prothoracic) leg disc has been generated. Here we present fate maps for the T2 (meso-) and T3 (metathoracic) leg discs. We show that there are many similarities to the map of the T1 leg disc. However, there are also significant differences in the contributions of each disc to the thorax, in the morphology of joints connecting the legs to the thorax, in bristle patterns, and in the positioning of some sensory organs. We also tested the developmental potential of disc fragments and observed that T2 and T3 leg discs have more limited plasticity and are unable to transdetermine. The differences in the cuticle patterns between legs are robust and conserved in many species of dipterans. While most previous analyses of imaginal disc development have not distinguished between the different leg discs, we believe that the underlying differences of the three leg discs demonstrated here cannot be ignored when studying leg disc development.
    MeSH term(s) Aging/physiology ; Animals ; Biomarkers/metabolism ; Body Patterning ; Drosophila melanogaster/growth & development ; Extremities/growth & development ; Imaginal Discs/growth & development ; Imaginal Discs/transplantation ; Regeneration/physiology
    Chemical Substances Biomarkers
    Language English
    Publishing date 2012-06-05
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 1114-9
    ISSN 1095-564X ; 0012-1606
    ISSN (online) 1095-564X
    ISSN 0012-1606
    DOI 10.1016/j.ydbio.2012.05.025
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Drosophila twin spot clones reveal cell division dynamics in regenerating imaginal discs.

    Sustar, Anne / Bonvin, Marianne / Schubiger, Margrit / Schubiger, Gerold

    Developmental biology

    2011  Volume 356, Issue 2, Page(s) 576–587

    Abstract: Cell proliferation is required for tissue regeneration, yet the dynamics of proliferation during regeneration are not well understood. Here we investigated the proliferation of eye and leg regeneration in fragments of Drosophila imaginal discs. Using ... ...

    Abstract Cell proliferation is required for tissue regeneration, yet the dynamics of proliferation during regeneration are not well understood. Here we investigated the proliferation of eye and leg regeneration in fragments of Drosophila imaginal discs. Using twin spot clones, we followed the proliferation and fates of sister cells arising from the same mother cell in the regeneration blastema. We show that the mother cell gives rise to two sisters that participate equally in regeneration. However, when cells switch disc identity and transdetermine to another fate, they fail to turn off the cell cycle and continue dividing long after regeneration is complete. We further demonstrate that the regeneration blastema moves as a sweep of proliferation, in which cells are displaced. Our results suggest that regenerating cells stop dividing once the missing parts are formed, but if they undergo a switch in cell fate, the proliferation clock is reset.
    MeSH term(s) Animals ; Bromodeoxyuridine/metabolism ; Cell Division ; Cell Proliferation ; Drosophila melanogaster/cytology ; Drosophila melanogaster/embryology ; Extremities/embryology ; Eye/embryology ; Regeneration
    Chemical Substances Bromodeoxyuridine (G34N38R2N1)
    Language English
    Publishing date 2011-06-23
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 1114-9
    ISSN 1095-564X ; 0012-1606
    ISSN (online) 1095-564X
    ISSN 0012-1606
    DOI 10.1016/j.ydbio.2011.06.018
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Regeneration and transdetermination: the role of wingless and its regulation.

    Schubiger, Margrit / Sustar, Anne / Schubiger, Gerold

    Developmental biology

    2010  Volume 347, Issue 2, Page(s) 315–324

    Abstract: Imaginal discs of Drosophila have the remarkable ability to regenerate. After fragmentation wound healing occurs, ectopic wg is induced and a blastema is formed. In some, but not all fragments, the blastema will replace missing structures and a few cells ...

    Abstract Imaginal discs of Drosophila have the remarkable ability to regenerate. After fragmentation wound healing occurs, ectopic wg is induced and a blastema is formed. In some, but not all fragments, the blastema will replace missing structures and a few cells can become more plastic and transdetermine to structures of other discs. A series of systematic cuts through the first leg disc revealed that a cut must transect the dorsal-proximal disc area and that the fragment must also include wg-competent cells. Fragments that fail to both transdetermine and regenerate missing structures will do both when provided with exogenous Wg, demonstrating the necessity of Wg in regenerative processes. In intact leg discs ubiquitously expressed low levels of Wg also leads to blastema formation, regeneration and transdetermination. Two days after exogenous wg induction the endogenous gene is activated, leading to elevated levels of Wg in the dorsal aspect of the leg disc. We identified a wg enhancer that regulates ectopic wg expression. Deletion of this enhancer increases transdetermination, but lowers the amount of ectopic Wg. We speculate that this lessens repression of dpp dorsally, and thus creates a permissive condition under which the balance of ectopic Wg and Dpp is favorable for transdetermination.
    MeSH term(s) Animals ; Animals, Genetically Modified ; Base Sequence ; DNA Primers/genetics ; Drosophila Proteins/genetics ; Drosophila Proteins/physiology ; Drosophila melanogaster/genetics ; Drosophila melanogaster/growth & development ; Drosophila melanogaster/physiology ; Enhancer Elements, Genetic ; Extremities/growth & development ; Extremities/physiology ; Genes, Insect ; Regeneration/genetics ; Regeneration/physiology ; Transcriptional Activation ; Wnt1 Protein/genetics ; Wnt1 Protein/physiology
    Chemical Substances DNA Primers ; Drosophila Proteins ; Wnt1 Protein ; dpp protein, Drosophila ; wg protein, Drosophila
    Language English
    Publishing date 2010-09-21
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 1114-9
    ISSN 1095-564X ; 0012-1606
    ISSN (online) 1095-564X
    ISSN 0012-1606
    DOI 10.1016/j.ydbio.2010.08.034
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Leftward bias in number space is modulated by magical ideation.

    Brugger, Peter / Schubiger, Michèle / Loetscher, Tobias

    Cognitive and behavioral neurology : official journal of the Society for Behavioral and Cognitive Neurology

    2010  Volume 23, Issue 2, Page(s) 119–123

    Abstract: Background: Productive symptoms of schizophrenia and positive-symptom schizotypy have both been related to signs of right-sided hemispatial inattention ("pseudoneglect"). We here set out to explore, in healthy subjects, the relationship between one form ...

    Abstract Background: Productive symptoms of schizophrenia and positive-symptom schizotypy have both been related to signs of right-sided hemispatial inattention ("pseudoneglect"). We here set out to explore, in healthy subjects, the relationship between one form of mild schizotypy ("magical ideation"; MI) and asymmetries in number space, which is a bias toward relatively small numbers, reportedly represented to the left of larger numbers.
    Methods: Forty right-handed participants filled in the MI scale and performed a number-line bisection (NLB) task and a randomization task (the Mental Dice Task, MDT, requiring randomization of the digits from 1 to 6).
    Results: We found pseudoneglect in number space, that is, more errors toward small numbers in the NLB task and an overproduction of small digits in the MDT. Individual participants' MI scores were correlated to the size of pseudoneglect in both numerical tasks.
    Conclusions: Explicit (NLB) and implicit (MDT) assessments of the exploration of number space may be relevant to studies of the mechanisms underlying the formation of delusional and schizotypal beliefs. We propose that, in healthy subjects, a trait-like imbalance in hemispheric cooperation may not only produce asymmetries in physical and representational space, but also predisposes to develop magical ideas. Specifically, an over-proportional influence of the right hemisphere semantic system (preferentially coding oblique and remote associations) leads to the assumption of connections between randomly associated events.
    MeSH term(s) Adult ; Bias ; Female ; Functional Laterality ; Humans ; Male ; Mental Processes ; Psychomotor Performance ; Space Perception
    Language English
    Publishing date 2010-06
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2108112-8
    ISSN 1543-3641 ; 1543-3633
    ISSN (online) 1543-3641
    ISSN 1543-3633
    DOI 10.1097/WNN.0b013e3181d74901
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Head turns bias the brain's internal random generator.

    Loetscher, Tobias / Schwarz, Urs / Schubiger, Michele / Brugger, Peter

    Current biology : CB

    2008  Volume 18, Issue 2, Page(s) R60–2

    MeSH term(s) Brain/physiology ; Cognition/physiology ; Head Movements/physiology ; Humans
    Language English
    Publishing date 2008-01-22
    Publishing country England
    Document type Letter ; Research Support, Non-U.S. Gov't
    ZDB-ID 1071731-6
    ISSN 1879-0445 ; 0960-9822
    ISSN (online) 1879-0445
    ISSN 0960-9822
    DOI 10.1016/j.cub.2007.11.015
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Genes for neural differentiation.

    Palka, J / Schubiger, M

    Trends in neurosciences

    1988  Volume 11, Issue 12, Page(s) 515–517

    MeSH term(s) Animals ; Cell Differentiation ; Drosophila ; Genes ; Neurons/cytology
    Language English
    Publishing date 1988-12
    Publishing country England
    Document type Journal Article
    ZDB-ID 282488-7
    ISSN 1878-108X ; 0166-2236 ; 0378-5912
    ISSN (online) 1878-108X
    ISSN 0166-2236 ; 0378-5912
    DOI 10.1016/0166-2236(88)90173-7
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Changing spatial patterns of DNA replication in the developing wing of Drosophila.

    Schubiger, M / Palka, J

    Developmental biology

    1987  Volume 123, Issue 1, Page(s) 145–153

    Abstract: Using an antibody against bromodeoxyuridine we have analyzed the distribution of S-phase nuclei in the wing disc of Drosophila as the larval disc transforms into the adult wing during metamorphosis. On the basis of the timing of replication three cell ... ...

    Abstract Using an antibody against bromodeoxyuridine we have analyzed the distribution of S-phase nuclei in the wing disc of Drosophila as the larval disc transforms into the adult wing during metamorphosis. On the basis of the timing of replication three cell populations can be distinguished: the cells of the presumptive wing margin, the precursor cells of the longitudinal veins, and those of the intervein regions. In each of these populations the cell cycle is first arrested and later resumes at a specific time, so that at each developmental time point a characteristic spatial pattern of S-phase nuclei is seen. An interpretation of these changing patterns in terms of vein formation, compartments, and neural development is offered.
    MeSH term(s) Animals ; Bromodeoxyuridine/metabolism ; DNA/analysis ; DNA Replication ; Drosophila/cytology ; Drosophila/genetics ; Drosophila/growth & development ; Larva ; Metamorphosis, Biological ; Wings, Animal/cytology
    Chemical Substances DNA (9007-49-2) ; Bromodeoxyuridine (G34N38R2N1)
    Language English
    Publishing date 1987-09
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S. ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 1114-9
    ISSN 1095-564X ; 0012-1606
    ISSN (online) 1095-564X
    ISSN 0012-1606
    DOI 10.1016/0012-1606(87)90436-2
    Database MEDical Literature Analysis and Retrieval System OnLINE

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