B=1 Soliton of the Nambu - Jona-Lasinio model in medium}

The solitonic sector of the Nambu - Jona-Lasinio model with baryon number one is solved in the presence of an external medium. The calculations fully include the polarization of both the Dirac sea and the medium as well as the Pauli blocking effect. We found that with an increasing density the medium destabilizes the soliton. At finite medium density the soliton mass gets reduced whereas the mean square baryon radius shows an increase - a swelling of the soliton. At some critical density of about two times nuclear matter density there is no localized solution - the soliton disappears.Comment: PHYSTEX, 14 pages, 5 figures (available upon request), Preprint RUB-TPII-26/9

Colorimetric Measurement of Triglycerides Cannot Provide an Accurate Measure of Stored Fat Content in Drosophila

Drosophila melanogaster has recently emerged as a useful model system in which to study the genetic basis of regulation of fat storage. One of the most frequently used methods for evaluating the levels of stored fat (triglycerides) in flies is a coupled colorimetric assay available as a kit from several manufacturers. This is an aqueous-based enzymatic assay that is normally used for measurement of mammalian serum triglycerides, which are present in soluble lipoprotein complexes. In this short communication, we show that coupled colorimetric assay kits cannot accurately measure stored triglycerides in Drosophila. First, they fail to give accurate readings when tested on insoluble triglyceride mixtures with compositions like that of stored fat, or on fat extracted from flies with organic solvents. This is probably due to an inability of the lipase used in the kits to efficiently cleave off the glycerol head group from fat molecules in insoluble samples. Second, the measured final products of the kits are quinoneimines, which absorb visible light in the same wavelength range as Drosophila eye pigments. Thus, when extracts from crushed flies are assayed, much of the measured signal is actually due to eye pigments. Finally, the lipoprotein lipases used in colorimetric assays also cleave non-fat glycerides. The glycerol backbones liberated from all classes of glycerides are measured through the remaining reactions in the assay. As a consequence, when these assay kits are used to evaluate tissue extracts, the observed signal actually represents the amount of free glycerols together with all types of glycerides. For these reasons, findings obtained through use of coupled colorimetric assays on Drosophila samples must be interpreted with caution. We also show here that using thin-layer chromatography to measure stored triglycerides in flies eliminates all of these problems

OS AVANÇOS DA ESCOLARIDADE FEMININA: DE QUAIS MULHERES ESTAMOS FALANDO?

In this article we seek to problematise female schooling rates in Brazil, using as a source of analysis data collected in surveys carried out by the 2021, 2022 and 2023 School Census, the IDHM and the PNAD. The results homogenise women and contribute to the reproduction of social inequalities by making groups of less educated women, especially black women, invisible. We also observed that there are studies that claim to increase gender equality in the educational sphere, but do not consider the specificities of class, race, ethnicity, place of residence, among other social markers that contribute to the invisibilisation of women, placing them in a situation of inferiority by making it extremely difficult for those who manage to access education and continue their studies. This makes it important to question the increase in women's schooling in a homogenous way, problematising specific groups. Research has shown that there has been an increase in women's schooling, but in the group of white, middle and upper class women who live mainly in urban areas.En este artículo buscamos problematizar las tasas de educación femenina en Brasil, tomando como fuente de análisis datos recopilados en investigaciones realizadas por el Censo Escolar de 2021, 2022, 2023, el IDHM y la PNAD. Vimos que los resultados homogeneizan a las mujeres y contribuyen a la reproducción de las desigualdades sociales al invisibilizar a grupos de mujeres menos educadas, especialmente a las mujeres negras. También observamos que existen investigaciones que afirman un aumento de la igualdad de género en el ámbito educativo, pero no consideran las especificidades de clase, raza, etnia, lugar de residencia, entre otros marcadores sociales que contribuyen a la invisibilidad de las mujeres, ubicándolas en una situación de inferioridad al dificultar el acceso a la educación y la continuación de los estudios a quienes pueden acceder a ella. Esto hace importante cuestionar el aumento de la educación de las mujeres de manera homogénea, problematizando a grupos específicos. Observamos en la investigación que hubo un aumento en el nivel educativo de las mujeres, pero en el grupo de las que son residentes blancas, de clase media y alta, especialmente en las zonas urbanas.No presente artigo buscamos problematizar os índices de escolaridade feminina no Brasil, tomando como fonte de análise, dados coletados nas pesquisas realizadas pelo Censo Escolar 2021, 2022, 2023, o IDHM e a PNAD. Vimos que os resultados homogeneízam as mulheres e contribuem para a reprodução das desigualdades sociais ao invisibilizar os grupos de mulheres menos escolarizadas, sobretudo as negras. Observamos também que existem pesquisas que alegam aumento na igualdade de gênero no âmbito educacional, mas não consideram as especificidades de classe, raça, etnia, lugar de moradia, entre outros marcadores sociais que contribuem para a invisibilização das mulheres, colocando-as em uma situação de inferioridade ao dificultarem o acesso a educação e a continuidade dos estudos para as que conseguem acessar. O que faz com que seja importante questionar o aumento da escolaridade das mulheres de forma homogênea, problematizando grupos específicos. Observamos nas pesquisas que houve um aumento da escolaridade de mulheres, mas no grupo das que são brancas, de classe média e alta, moradoras, sobretudo das áreas urbanas

Recurrence of particles in static and time varying oval billiards

Dynamical properties are studied for escaping particles, injected through a hole in an oval billiard. The dynamics is considered for both static and periodically moving boundaries. For the static boundary, two different decays for the recurrence time distribution were observed after exponential decay for short times: A changeover to: (i) power law or; (ii) stretched exponential. Both slower decays are due to sticky orbits trapped near KAM islands, with the stretched exponential apparently associated with a single group of large islands. For time dependent case, survival probability leads to the conclusion that sticky orbits are less evident compared with the static case.Comment: 7 pages, 6 figures, to appear in Phys Lett

Fires in the Amazon region: quick policy review.

Motivation: The combination of institutional weaknesses, climate change, and overexploitation is increasingly recognized as endangering the Amazon forest. These three factors made 2020 the worst year for forest fires recorded in the previous 60 years. We analyse environmental policies across the nine countries of the Amazon Basin to develop national and regional forest programmes to tackle this scenario. Purpose: The study synthesizes and compares key environmental legislation concerning protected natural areas (PNAs) and fire management in the nine countries of the Amazon Basin. To this end, the research question asks what directions can be drawn from a visualization and compilation of national regulations for future policy research and practice. Methods and approach: We undertake a critical literature review of PNAs and fire-management policies across the nine countries of the Amazon Basin and their further alignment using analyses of previous policy reviews on forest codes and land distribution. Findings: The article shows the heterogeneity of national fire-use and fire-management policies among the nine countries of the Amazon Basin. In addition, it suggests that top-down policies and regulations are likely to be characterized by misunderstandings (either direct or indirect) of local practice, rationale, and capacity; and, in some cases, risk criminalizing local and indigenous daily subsistence. Policy implications: The study indicates the need for more in-depth research and policy on participatory governance platforms for the use and management of fire, rather than fire-suppression and fire-risk adaptation strategies. There are some positive, albeit often isolated, cases, to which scholars, policy-makers, and environmental practitioners should pay more attention.On-line first

Search for Axionlike and Scalar Particles with the NA64 Experiment

We carried out a model-independent search for light scalar (s) and pseudoscalar axionlike (a) particles that couple to two photons by using the high-energy CERN SPS H4 electron beam. The new particles, if they exist, could be produced through the Primakoff effect in interactions of hard bremsstrahlung photons generated by 100 GeV electrons in the NA64 active dump with virtual photons provided by the nuclei of the dump. The a(s) would penetrate the downstream HCAL module, serving as shielding, and would be observed either through their $a(s)\to\gamma \gamma$ decay in the rest of the HCAL detector or as events with large missing energy if the a(s) decays downstream of the HCAL. This method allows for the probing the a(s) parameter space, including those from generic axion models, inaccessible to previous experiments. No evidence of such processes has been found from the analysis of the data corresponding to $2.84\times10^{11}$ electrons on target allowing to set new limits on the $a(s)\gamma\gamma$-coupling strength for a(s) masses below 55 MeV.Comment: This publication is dedicated to the memory of our colleague Danila Tlisov. 7 pages, 5 figures, revised version accepted for publication in Phys. Rev. Let

What we talk about when we talk about "global mindset": managerial cognition in multinational corporations

Recent developments in the global economy and in multinational corporations have placed significant emphasis on the cognitive orientations of managers, giving rise to a number of concepts such as “global mindset” that are presumed to be associated with the effective management of multinational corporations (MNCs). This paper reviews the literature on global mindset and clarifies some of the conceptual confusion surrounding the construct. We identify common themes across writers, suggesting that the majority of studies fall into one of three research perspectives: cultural, strategic, and multidimensional. We also identify two constructs from the social sciences that underlie the perspectives found in the literature: cosmopolitanism and cognitive complexity and use these two constructs to develop an integrative theoretical framework of global mindset. We then provide a critical assessment of the field of global mindset and suggest directions for future theoretical and empirical research

Baryons as non-topological chiral solitons

The present review gives a survey of recent developments and applications of the Nambu--Jona-Lasinio model with $N_f=2$ and $N_f=3$ quark flavors for the structure of baryons. The model is an effective chiral quark theory which incorporates the SU(N$_f$)$_L\otimes$SU(N$_f$)$_R\otimes$U(1)$_V$ approximate symmetry of Quantum chromodynamics. The approach describes the spontaneous chiral symmetry breaking and dynamical quark mass generation. Mesons appear as quark-antiquark excitations and baryons arise as non-topological solitons with three valence quarks and a polarized Dirac sea. For the evaluation of the baryon properties the present review concentrates on the non-linear Nambu--Jona-Lasinio model with quark and Goldstone degrees of freedom which is identical to the Chiral quark soliton model obtained from the instanton liquid model of the QCD vacuum. In this non-linear model, a wide variety of observables of baryons of the octet and decuplet is considered. These include, in particular, electromagnetic, axial, pseudoscalar and pion nucleon form factors and the related static properties like magnetic moments, radii and coupling constants of the nucleon as well as the mass splittings and electromagnetic form factors of hyperons. Predictions are given for the strange form factors, the scalar form factor and the tensor charge of the nucleon.Comment: 104 pages, 27 figures as uuencoded and compressed postscript files , hardcopy available upon request; Prog.Part.Nucl.Phys. 37 (1996) (in print