41 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
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
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
Validation of a minimum microclimate disturbance chamber for net ecosystem flux measurements
A minimum-disturbance chamber for canopy net CO2 and H2O flux measurements is described. The system is a passively (optionally actively) ventilated tunnel with large (similar to 0.14 m2) in- and outlet cross sections covering a surface area of approximately 1.6 m2. A differential, non-drying closed-path gas analyzer is used to minimize the requirement for concentration build-ups or drawdowns between the in- and outlet, and 0.05 mm thick FEP (fluorinated ethylene propylene) film is used as top and wall material to minimize radiation modifications. First measurement results in passively ventilated mode are presented from two different sites: a wheat field at a lowland site in the westernmost part of Germany, and differently cropped adjacent fields in the Pyrenee foothills in France, including grassland and a cereal-dominated crop mixture for fodder production. Flux estimates derived from measurements over 20–30 min deployments were compared to concurrent observations by three eddy covariance (EC) stations. The system compared well to EC measurements, with bias of -6.6% for latent heat flux and +9.0% for CO2 flux (R2 = 0.78 and 0.74, respectively). The presence of the chamber causes a reduction of less than 4% in incoming shortwave radiation, and an increase of about 18% in downward longwave radiation. Near the outlet, CO2 concentration was on average modified by -3% with respect to outside conditions, water vapour concentration by +22%, and temperature by +0.9 K, staying below published modifications of a comparable non-steady-state chamber closed for 2 min. Ventilation speed varied by less than 9% across the inlet cross section. Limitations include a minimum wind speed requirement that can be set as low as 0.2 m s-1 for a raw data logging frequency of 1 s-1 or higher, but would need to be higher for slow-response gas analyzers. At the same time, a measurement period of 10 min or more is recommended to minimize random errors from storage term fluctuations. A correction for the added water vapour volume by evapotranspiration is derived and tested, which typically affects H2O flux itself by less than +2% and CO2 flux measurements by 1 µmol/J latent hea