2,127 research outputs found
Migration aspirations and migration cultures:A case study of Ukrainian migration towards the European Union
An abundant body of research focused on macrolevel, mesolevel, and microlevel factors explaining why individuals move across international borders. In this paper, we aim to complement the existing literature by exploring how, within a single country, mesolevel factors differently impact migration aspirations, focusing on a case study of Ukraine. We particularly focus on how migration aspirations of individuals in two different regions can be explained by their international social networks with family members, on the one hand, and with friends, on the other. Furthermore, we explore whether regional migration characteristics play a role, as well as the interaction of such characteristics with individuals' frequency of contact with transnational networks. Our analyses are based on the EUMAGINE project and suggest that the interplay between regional migration characteristics and transnational social contact are key for explainingthe decline of migration systems over time
Destination choices of international students in the Netherlands:A meso‐level analysis of higher education institutions and cities
This study quantitatively investigates enrolments of international students using data that contains nearly every student in the Netherlands for the years 2016–2019. Using this data, we are able to perform a meso-level analysis where we could investigate the characteristics of higher education institutions (HEIs) and cities in international student mobility. This research contributes to the literature by studying variation between HEIs and by focusing on actual enrolments instead of relying on survey results. Such meso-level studies have thus far been very rare, especially on this scale. Although there are commonalities between types of degrees, we find mixed results for academic and city characteristics, and it appears that academic factors are more important for master students while for bachelor students city characteristics have stronger effects. The effect of having already existing stocks of international students appears to be important for all types of degrees. Aside from differences between bachelor and master students, our findings also suggest that HEIs might directly influence international student flows as this would explain some of our results. Although this study only focuses on the Netherlands, it opens up many avenues for future comparative research on the destination choices of international students and the role of HEIs
International student mobility and labour market outcomes: an investigation of the role of level of study, type of mobility, and international prestige hierarchies
Over the last decades, there has been increasing interest in the topic of international student mobility (ISM). However, there is surprisingly little analysis of the ways in which different characteristics and types of short-term ISM or the importance of host education systems and labour markets may affect early career outcomes of formerly mobile graduates. Therefore, in this study we explore, first, the relationship between participation in ISM at the Bachelor and Master level and graduates’ wages and the duration of education-to-work transitions. Second, we investigate variations in ISM’s labour market outcomes according to the type of mobility: study, internships, or combinations of both. Third, we examine the relationship between labour market outcomes of formerly mobile students and the country of destination’s position in higher education international prestige hierarchies and labour market competitiveness. We use the Dutch National Alumni Survey 2015, a representative survey of higher education graduates in the Netherlands, conducted 1.5 years after graduation. Before controlling for selection into ISM, the results suggest the existence of labour market returns to ISM and that the heterogeneity of ISM experiences matters, as labour market outcomes vary according to the level of study, the type of mobility and the positioning of the country of destination in international prestige hierarchies. However, after controlling for selection into ISM through propensity score matching, the differences in early career outcomes between formerly mobile and non-mobile graduates disappear, suggesting that they cannot be causally attributed to their ISM-experience. We explain these results with reference to the characteristics of the Dutch education system and labour market, where restricted possibilities for upward vertical mobility limit returns to ISM in the local labour market
Improving web survey efficiency:the impact of an extra reminder and reminder content on web survey response
With the growing possibilities for conducting web surveys, researchers increasingly use such surveys to recruit student samples for research purposes in a wide array of social science disciplines. Simultaneously, higher education students are recurrently asked to complete course and teacher evaluations online and to participate in small-scale research projects of fellow students, potentially leading to survey fatigue among student populations across the globe. One of the most frequently reported effects of over-surveying is a decrease in overall response rates. This situation has significant impacts on the generalizability and external validity of findings based on web surveys. The collection of reliable data is, nevertheless, crucial for researchers as well as educational practitioners and administrators, and strategies should be developed for achieving acceptable response rates. This paper reports on a methodological experiment (N = 15,651) conducted at the University of Antwerp, Belgium, in which possible strategies to improve survey response are explored. I specifically focus on the impact of an extra reminder as well as specific reminder contents on response rates. The results reveal that extra reminders are effective for increasing response rates, but not for diversifying the sample
Traditional mixed linear modelling versus modern machine learning to estimate cow individual feed intake
Three modelling approaches were used to estimate cow individual feed intake(FI) using feeding trial data from a research farm, including weekly recordingsof milk production and composition, live-weight, parity, and total FI.Additionally, weather data (temperature, humidity) were retrieved from theDutch National Weather Service (KNMI). The 2014 data (245 cows; 277parities) were used for model development. The first model (M1) applied anexisting formula to estimate energy requirement using parity, fat and proteincorrected milk, and live-weight, and assumed this requirement to be equal toenergy intake and thus FI. The second model used ‘traditional’ Mixed LinearRegression, first using the same variables as in M1 as fixed effects (MLR1), andthen by adding weather data (MLR2). The third model applied BoostedRegression Tree, a ‘modern’ machine learning technique, again once with thesame variables as M1 (BRT1), and once with weather information added(BRT2). All models were validated on 2015 data (155 cows; 165 parities) usingcorrelation between estimated and actual FI to evaluate performance. BothMLRs had very high correlations (0.91) between actual and estimated FI on 2014data, much higher than 0.46 for M1, and 0.73 for both BRTs. When validated on2015 data, correlations dropped to 0.71 for MLR1 and 0.72 for MLR2, andincreased to 0.71 for M1 and 0.76 for both BRTs. FI estimated by BRT1 was, onaverage, 0.35kg less (range: -7.61 – 13.32kg) than actual FI compared to 0.52kgless (range: -11.67 – 19.87kg) for M1. Adding weather data did not improve FIestimations
Development and application of an algorithm for detecting <i>Phaeocystis globosa</i> blooms in the Case 2 Southern North Sea waters
While mapping algal blooms from space is now well-established, mapping undesirable algal blooms in eutrophicated coastal waters raises further challenge in detecting individual phytoplankton species. In this paper, an algorithm is developed and tested for detecting Phaeocystis globosa blooms in the Southern North Sea. For this purpose, we first measured the light absorption properties of two phytoplankton groups, P. globosa and diatoms, in laboratory-controlled experiments. The main spectral difference between both groups was observed at 467 nm due to the absorption of the pigment chlorophyll c3 only present in P. globosa, suggesting that the absorption at 467 nm can be used to detect this alga in the field. A Phaeocystis-detection algorithm is proposed to retrieve chlorophyll c3 using either total absorption or water-leaving reflectance field data. Application of this algorithm to absorption and reflectance data from Phaeocystis-dominated natural communities shows positive results. Comparison with pigment concentrations and cell counts suggests that the algorithm can flag the presence of P. globosa and provide quantitative information above a chlorophyll c3 threshold of 0.3 mg m-3 equivalent to a P. globosa cell density of 3 × 106 cells L-1. Finally, the possibility of extrapolating this information to remote sensing reflectance data in these turbid waters is evaluated
Using an intervention mapping approach to develop a discharge protocol for intensive care patients
Background: Admission into an intensive care unit (ICU) may result in long-term physical, cognitive, and emotional consequences for patients and their relatives. The care of the critically ill patient does not end upon ICU discharge; therefore, integrated and ongoing care during and after transition to the follow-up ward is pivotal. This study described the development of an intervention that responds to this need. Methods: Intervention Mapping (IM), a six-step theory- and evidence-based approach, was used to guide intervention development. The first step, a problem analysis, comprised a literature review, six semi-structured telephone interviews with former ICU-patients and their relatives, and seven qualitative roundtable meetings for all eligible nurses (i.e., 135 specialized and 105 general ward nurses). Performance and change objectives were formulated in step two. In step three, theory-
Effect of helium pre- or postconditioning on signal transduction kinases in patients undergoing coronary artery bypass graft surgery
Background: The noble gas helium induces pre- and postconditioning in animals and humans. Volatile anesthetics induce cardioprotection in humans undergoing coronary artery bypass graft (CABG) surgery. We hypothesized that helium induces pre-and postconditioning in CABG-patients, affecting signaling molecules protein kinase C-epsilon (PKC-epsilon), p38 mitogen activated protein kinase (p38 MAPK), extracellular signal-regulated kinase 1/2 (ERK-1/2) and heat shock protein 27 (HSP-27) within cardiac tissue, and reducing postoperative troponin levels.
Methods: After ethical approval and informed consent, 125 elective patients undergoing CABG surgery were randomised into this prospective, placebo controlled, investigator blinded, parallel arm single-centre study. Helium preconditioning (3 x 5 min of 70 % helium and 30 % oxygen) was applied before aortic cross clamping; postconditioning (15 min of helium) was applied before release of the aortic cross clamp. Signaling molecules were measured in right atrial appendix specimens. Troponin-T was measured at 4, 12, 24 and 48 h postoperatively.
Results: Baseline characteristics of all groups were similar. Helium preconditioning did not significantly alter the primary outcome (molecular levels of kinases PKC-e and HSP-27, ratio of activated p38 MAPK or ERK 1/2). Postoperative troponin T was 11 arbitrary units [5, 31; area-under-the-curve (interquartile range)] for controls, and no statistically significant changes were observed after helium preconditioning [He-pre: 11 (6, 18)], helium postconditioning [He-post: 11 (8, 15)], helium pre-and postconditioning [He-PP: 14 (6, 20)] and after sevoflurane preconditioning [APC: 12 (8, 24), p = 0.13]. No adverse effects related to study treatment were observed in this study.
Conclusions: No effect was observed of helium preconditioning, postconditioning or the combination thereof on activation of p38 MAPK, ERK 1/2 or levels of HSP27 and PKC-e in the human heart. Helium pre-and postconditioning did not affect postoperative troponin release in patients undergoing CABG surgery
How to measure camouflaging? A conceptual replication of the validation of the Camouflaging Autistic Traits Questionnaire in Dutch adults
Background: Camouflaging behavior is often defined as using strategies to hide autistic characteristics. In this study, we investigated how to measure camouflaging behavior by performing a conceptual replication of the original study of the Camouflaging Autistic Traits Questionnaire (CAT-Q) and testing whether the self-reported camouflaging behavior is measuring the same construct as the second most used manner to measure camouflaging behavior, the discrepancy method. Method: In total, 674 individuals (356 autistic) aged 30–92 years, filled out the Dutch translation of the CAT-Q (CAT-Q-NL) and the Autism Spectrum Quotient (AQ). In 90 autistic adults the Autism Diagnostic Observation Schedule (ADOS-2) was administered. We executed preregistered analyses (AsPredicted #37800) to investigate the factor structure, measurement invariance, internal consistency, convergent validity and group differences. Results: Our analyses showed that the original three-factor structure had an acceptable fit and internal consistency ranged from sufficient to good. However, there was no measurement invariance between autistic and non-autistic individuals and correlations between CAT-Q-NL-scores and the discrepancy between AQ and ADOS-2 varied between low to mediocre (r = 0.04 to.28). Conclusions: The CAT-Q-NL can be used to measure camouflaging between and within autistic adults, but not between autistic and non-autistic adults and its convergent validity is limited. Despite these caveats, the CAT-Q-NL can serve as a useful addition to the clinical assessment toolbox because gaining insight in the level of camouflaging of autistic adults may help provide better mental health care. However, more research is needed into how to optimally measure the camouflaging construct
Radiocarbon Chronologies and Extinction Dynamics of the Late Quaternary Mammalian Megafauna of the Taimyr Peninsula, Russian Federation
This paper presents 75 new radiocarbon dates based on late Quaternary mammal remains recovered from eastern Taimyr Peninsula and adjacent parts of the northern Siberian lowlands, Russian Federation, including specimens of woolly mammoth (Mammuthus primigenius), steppe bison (Bison priscus), muskox (Ovibos moschatus), moose (Alces alces), reindeer (Rangifer tarandus), horse (Equus caballus) and wolf (Canis lupus). New evidence permits reanalysis of megafaunal extinction dynamics in the Asian high Arctic periphery. Increasingly, radiometric records of individual species show evidence of a gap at or near the Pleistocene/Holocene boundary (PHB). In the past, the PHB gap was regarded as significant only when actually terminal, i.e., when it marked the apparent ‘‘last’’ occurrence of a species (e.g., current ‘‘last’’ occurrence date for woolly mammoth in mainland Eurasia is 9600 yr BP). However, for high Arctic populations of horses and muskoxen the gap marks an interruption rather than extinction, because their radiocarbon records resume, nearly simultaneously, much later in the Holocene. Taphonomic effects, ΔC14 flux, and biased sampling are unlikely explanations for these hiatuses. A possible explanation is that the gap is the signature of an event, of unknown nature, that prompted the nearly simultaneous crash of many megafaunal populations in the high Arctic and possibly elsewhere in Eurasia.
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