49 research outputs found
Observables of the Euclidean Supergravity
The set of constraints under which the eigenvalues of the Dirac operator can
play the role of the dynamical variables for Euclidean supergravity is derived.
These constraints arise when the gauge invariance of the eigenvalues of the
Dirac operator is imposed. They impose conditions which restrict the
eigenspinors of the Dirac operator.Comment: Revised version, some misprints in the ecuations (11), (13) and (17)
corrected. The errors in the published version will appear cortected in a
future erratu
Linguistic foundations of heritage language development from the perspective of romance languages in Germany
This paper discusses the role of different factors determining the linguistic competence of heritage speakers (HSs) based on examples from speakers who speak a Romance language (French, Italian, Portuguese, or Spanish) as heritage language (HL) and German as the environmental language. Since the relative amount of contact with the HL and the environmental language may vary during the acquisition process, the role of language dominance (in terms of relative language proficiency) is of particular interest for HL development. In addition to dominance (and related to it), cross-linguistic influence (CLI) may have an influence on the outcome of HL acquisition. Finally, quality and quantity of input also determine HL acquisition and will be discussed in connection with heritage language education.info:eu-repo/semantics/publishedVersio
Filtered multiplicative bases of restricted enveloping algebras
We study the problem of the existence of filtered multiplicative bases of a restricted enveloping algebra u(L), where L is a finite-dimensional and p-nilpotent restricted Lie
algebra over a field of positive characteristic p
Inter-generational transmission in a minority language setting: Stop consonant production by Bangladeshi heritage children and adults
Aims and objectives: The purpose of this study was to gain a better understanding of speech development across successive generations of heritage language users, examining how cross-linguistic, developmental and socio-cultural factors affect stop consonant production.
Design: To this end, we recorded Sylheti and English stop productions of two sets of Bangladeshi heritage families: (1) first-generation adult migrants from Bangladesh and their (second-generation) UK-born children, and (2) second-generation UK-born adult heritage language users and their (third-generation) UK-born children.
Data and analysis: The data were analysed auditorily, using whole-word transcription, and acoustically, examining voice onset time. Comparisons were then made in both languages across the four groups of participants, and cross-linguistically.
Findings: The results revealed non-native productions of English stops by the first-generation migrants but largely target-like patterns by the remaining sets of participants. The Sylheti stops exhibited incremental changes across successive generations of speakers, with the third-generation children’s productions showing the greatest influence from English.
Originality: This is one of few studies to examine both the host and heritage language in an ethnic minority setting, and the first to demonstrate substantial differences in heritage language accent between age-matched second- and third-generation children. The study shows that current theories of bilingual speech learning do not go far enough in explaining how speech develops in heritage language settings.
Implications: These findings have important implications for the maintenance, transmission and long-term survival of heritage languages, and show that investigations need to go beyond second-generation speakers, in particular in communities that do not see a steady influx of new migrants
Input effects across domains:The case of Greek subjects in child heritage language
A recurring question in the literature of heritage language acquisition, and more generally of bilingual acquisition, is whether all linguistic domains are sensitive to input reduction and to cross-linguistic influence and to what extent. According to the Interface Hypothesis, morphosyntactic phenomena regulated by discourse–pragmatic conditions are more likely to lead to non-native outcomes than strictly syntactic aspects of the language (Sorace, 2011). To test this hypothesis, we examined subject realization and placement in Greek–English bilingual children learning Greek as a heritage language in North America and investigated whether the amount of heritage language use can predict their performance in syntax–discourse and narrow syntactic contexts. Results indicated two deviations from the Interface Hypothesis: First, subject realization (a syntax–discourse phenomenon) was found to be largely unproblematic. Second, subject placement was affected not only in syntax–discourse structures but also in narrow syntactic structures, though to a lesser degree, suggesting that the association between the interface status of subject placement and its sensitivity to heritage language use among children heritage speakers is gradient rather than categorical
The Gender Congruency Effect across languages in bilinguals: A meta-analysis
In the study of gender representation and processing in bilinguals, two contrasting perspectives exist: integrated vs. the autonomous (Costa, Kovacic, Fedorenko, & Caramazza, 2003). In the former, cross-linguistic interactions during the selection of grammatical gender values are expected; in the latter, they are not. To address this issue, authors have typically explored the cross-linguistic Gender Congruency Effect (GCE: a facilitation on the naming or translation of second language [L2] nouns when their first language [L1] translations are of the same gender, in comparison to those of a different gender). However, the literature suggests that this effect is sometimes difficult to observe and might vary as a function of variables such as the syntactic structure produced to translate or name the target (bare nouns vs. noun phrases), the phonological gender transparency of both languages (whether or not they have phonological gender cues associated with the ending letter [e.g., “–a” for feminine words and “–o” for masculine words in Romance languages]), the degree of L2 proficiency, and task requirements (naming vs. translation). The aim of the present quantitative meta-analysis is to examine the robustness of the cross-linguistic GCE obtained during language production. It involves 25 experiments from 11 studies. The results support a bilingual gender-integrated view, in that they show a small but significant GC effect regardless of the variables mentioned above.This paper was funded through the state budget with reference IF / 00784/2013 / CP1158 / CT0013. The study has also been partially supported by the FCT and the Portuguese Ministry of Science, Technology and Higher Education through national funds and co-financed by FEDER through COMPETE2020 under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007653). Government of Spain—Ministry of Education, Culture and Sports—through the Training program for Academic Staff (Ayudas para la Formación del Profesorado Universitario, FPU grant BOE-B-2017-2646), the research project (reference PSI2015-65116-P) granted by the Spanish Ministry of Economy and Competitiveness, and the grant for research groups (reference ED431B 2019/2020) from the Galician Government, as well as by the FCT (Foundation for Science and Technology, Portugal) through the state budget (reference IF / 00784/2013 / CP1158 / CT0013). Finally, the study has also been partially supported by the FCT and the Portuguese Ministry of Science, Technology and Higher Education through national funds and co-financed by FEDER through COMPETE2020 under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007653
Analyzing transient closed chamber effects on canopy gas exchange for optimizing flux calculation timing
Transient type canopy chambers are still the only currently available practical solution for rapid screening of gas-exchange in agricultural fields. The technique has been criticized for its effect on canopy microclimate during measurement which affects the transport regime and regulation of plant gas-exchange. Field studies in which the technique has been compared against independent methods are still fragmentary. The aims of this study were to quantify the changes of the physical environment during chamber placement, to determine optimum flux measuring windows, to compare three flux-calculation procedures, and to test the performance of the method against independent measurements of sap-flow. Two wheat experiments were conducted for these purposes under German temperate climate conditions. Leaf transpiration and sap-flow remained relatively constant during the first 120 s after chamber deployment, but changed considerably afterwards. Canopy H2O fluxes could thus be inferred from concentration measurement series during this interval. A saturation function, previously not mentioned in the literature, was compared against the commonly used constant and quadratic regression methods and identified as the most suitable method for calculating vapor fluxes. The study reconfirmed that small proportional changes of CO2 concentrations during the calculation interval facilitate the application of the frequently applied quadratic regression method for calculating CO2 fluxes. Sap-flow, leaf and canopy gas-exchange were severely perturbed after chamber removal. Revisiting times of same sample locations need to be planned accordingly. The study confirms that the transient chamber technique can be applied for determining canopy gas-exchange, provided that characteristic time intervals within concentration measuring series are determined and their non-linearity tested to establish appropriate flux calculation procedures
Crop growth patterns at the field scale: Detection, understanding and modeling
Agricultural ecosystems are shaped by environmental factors, weather and soil characteristics in
particular. Heterogeneities of these conditions cause spatial variations of biomass, yield and leaf area
index in agricultural fields. The effects of varying spatial conditions on crop growth are generally
examined at distinct spatial scales. However, only few address spatial heterogeneity at the field level.
Since crop growth models try to represent reality, they should ideally mimic the effect of variations in
soil conditions on crop growth and development. Some studies showed that the tested models are
able to represent spatial heterogeneity in plant development and growth at regional scale, if
parameters of environmental conditions are adapted. We hypothesize that taking into account the
effects of soil heterogeneity on plant water and nutrient uptake also improves the accuracy of crop
growth model simulations at the field scale. A crop growth model was applied using information
from winter wheat and sugar beet field trials near Jülich, located in the central western part of
Germany, from 2010 to 2012. These fields are characterized by strong spatial variability in soil
conditions and managed according to standard agronomic practice. The crop growth model was
calibrated separately for each winter wheat and sugar beet cultivar grown on these fields by
adjusting the respective parameters with the help of crop physiological measurements carried out at
point level. The soil model was parameterized for different field sample points with measurements of
apparent soil electromagnetic conductivity (ECa) to account for the spatial heterogeneity in soil
conditions within each field. The crop growth model was subsequently tested whether it could
reproduce the observed spatial patterns of crop growth in the selected fields by considering the
spatial variability in soil properties. The analysis of the above mentioned measurements in the winter
wheat and sugar beet fields revealed a distribution of soil properties whose patterns are reflected in
crop growth. When the ECa of the soil was high, the crop produced more leaf area, biomass and yield
as a crop grown in soils with a lower ECa. This relation was far less expressive in more uniform fields.
We therefore assume that the interaction of soil ECa and crop growth strengthens with increasing
soil heterogeneity. Due to the given relationship between the ECa of the soil and crop growth, the
detected field patterns were used to validate the crop growth model GECROS. Since this model
includes a dynamic photosynthesis module, which is directly interacting with atmospheric input and
the coupled soil model SLIM, we validated it regarding its ability to represent our measured crop
data. When SLIM is parameterized by ECa data, the simulated crop data showed a stronger
accordance with the measured crop data than simulation runs without the adaption of the soil
model