Revealing hidden symmetries and gauge invariance of the massive Carroll-Field-Jackiw model

In this paper we have analyzed the improved version of the Gauge Unfixing (GU) formalism of the massive Carroll-Field-Jackiw model, which breaks both the Lorentz and gauge invariances, to disclose hidden symmetries to obtain gauge invariance, the key stone of the Standard Model. In this process, as usual, we have converted this second-class system into a first-class one and we have obtained two gauge invariant models. We have verified that the Poisson brackets involving the gauge invariant variables, obtained through the GU formalism, coincide with the Dirac brackets between the original second-class variables of the phase space. Finally, we have obtained two gauge invariant Lagrangians where one of them represents the Stueckelberg form.Comment: revised version. To appear in Europhysics Letter

Conserved Karyotypes In The Hyla Pulchella Species Group (anura, Hylidae)

Cytogenetic analyses were done on specimens of Hyla marginata and on three populations H. semiguttata differing in morphology and in the physical parameters of their advertisement call, as well as in individuals of Hyla sp. (aff. semiguttata). All specimens had 2n = 24 chromosomes with a morphology very similar to that of other 24-chromosome Hyla species. Hyla semiguttata and H. marginata showed the same C-banding pattern but were distinguished by the location of the NOR on pair 1 in H. semiguttata (in the three populations) and Hyla sp. (aff. semiguttata), and on pair 10 in H. marginata. The H. semiguttata populations did not differ cytogenetically, despite variations in their morphology and advertisement calls. Similarly, H. semiguttata and H. p. joaquini studied previously had identical C-banding patterns and NOR locations, suggesting that they are very closely related.14014248Ananias, F., Caracterização cromossômica de espécies e subespécies de Hyla do grupo pulchella (Amphibia, Anura, Hylidae) (1996), Master thesis. - State Univ. of Campinas (UNICAMP), SP, BrazilAnderson, K., Chromosome evolution in Holarctic Hyla treefrogs (1991) Amphibian Cytogenetics and Evolution, pp. 299-331. , Green, M. G. and Sessions, S. K (eds), Academic PressBaldissera Jr., F.A., Oliveira, P.S.L., Kasahara, S., Cytogenetics of four Brazilian Hyla species (Amphibia-Anura) and description of a case with a supernumerary chromosome (1993) Rev. Bras. Genet., 16, pp. 335-345Beçak, M.L., Chromosomal analysis of eighteen species of Anura (1968) Caryologia, 21, pp. 191-208Bogart, J.P., Evolution of anuran karyotypes (1973) Evolutionary Biology of Anurans, pp. 337-349. , Vial, J. L. (ed.), Univ. Missouri PressBraun, P.C., Braun, C.A.S., Lista prévia dos anfíbios do Rio Grande do Sul, Brasil (1980) Iheringia, Ser. Zool., Porto Alegre, 56, pp. 121-146Caramaschi, U., Cruz, C.A.G., Duas espécies novas de Hyla Laurenti, 1768 do Estado de Goiás, Brasil (Amphibia, Anura, Hylidae) (2000) Bol. Mus. Nac. Zool., 422, pp. 1-12Cei, J.M., Roig, V.G., Batracios recolectados por la espedición biologica Erspamer en Corrientes y selva oriental de Misiones (1961) Notas Biol. Facult. Ciencias Exactas, Fisicas Y Naturales, Corrientes Zool., 1, p. 10Duellman, W.E., De La Riva, I., Wild, E.R., Frogs of the Hyla armata and Hyla pulchella groups in the Andes of South America, with definitions and analyses of phylogenetic relationships of Andean groups of Hyla (1997) Sci. Papers Nat. Hist. Mus. Univ. Kansas, 3, pp. 1-41Faivovich, J., La larva de Hyla semiguttata A. Lutz, 1925 (Anura, Hylidae) (1996) Cuadernos de Herpetol., 9, pp. 61-67Garcia, P.C.A., Haddad, C.F.B., Análise das vocalizações de anúncio (advertisement call) das espécies de Hyla relacionadas ao complexo de Hyla marginata/semiguttata (Amphibia, Anura, Hylidae) (1999) Res. V, Cong. Lat. Am. Herpetol., p. 64Garcia, P.C.A., Vinciprova, G., Haddad, C.F.B., Vocalização, girino, distribuição geográ fica e novos comentários sobre Hyla marginata Boulenger, 1887 (Anura, Hylidae, Hylinae) (2001) Bol. Mus. Nac. Zool., 460, pp. 1-19Goldman, N., Barton, N.H., Genetics and geography (1992) Nature, 357, pp. 440-441Green, D.M., Session, S.K., Nomenclature for chromosomes (1991) Amphibian Cytogenetics and Evolution, pp. 431-432. , Green, D. M. and Sessions, S. K. (eds), Academic PressHerrero, P., López-Jurado, L.F., Arano, B., Karyotype analysis and nuclear DNA content of Bufo brongersmai Hoogmoed (1993) J. Herpetol., 27, pp. 463-465Howell, W.M., Black, D.A., Controlled silver-staining of nucleolus organizer regions with a protective colloidal developer:1-step method (1980) Experientia, 36, pp. 1014-1015Kaiser, H., Mais, C., Bolaños, F., Chromosomal investigation of three Costa Rica frogs from the 30-chromosome radiation of Hyla with the description of a unique geographic variation in nucleolus organizer regions (1996) Genetica, 98, pp. 95-102Kasahara, S., Silva, A.P.Z., Haddad, C.F.B., Chromosome banding in three species of Brazilian toads (Amphibia-Bufonidae) (1996) Braz. J. Genet., 19, pp. 237-242King, M., Amphibian (1990) Animal Cytogenetics, pp. 1-241. , John, B. (ed.), Gebrüder Borntraeger, Berlin/StuttgartKuramoto, M., A list of chromosome numbers of anuran amphibians (1990) Bull. Fukuoka Univ. Ed., 39, pp. 83-127Langone, J.A., Caráterización, sinonimia y distribución geográfica de H. marginata Boulenger 1887 (Amphibia, Anura, Hylidae) (1993) Res. III Cong. Lat. Herpetol., p. 228Langone, J.A., Caráterizaçción de Hyla guentheri Boulenger, 1886 (Amphibia, Anura, Hylidae) (1997) Cuad. Herpetol., 11, pp. 13-20Lutz, A., Batraciens du Brésil. II (1925) Compt. Ren. Soc. Biol. Paris., 93 (22), pp. 211-214Lutz, B., Brasilian species of Hyla (1973), pp. 74-85. , Texas Univ. PressMatsui, M., Seto, T., Kohsaka, Y., Bearing of chromosome C-banding patterns on the classification of Eurasian toads of the Bufo bufo complex (1985) Amphibia-Reptilia, 6, pp. 23-33Miura, I., The late replication banding patterns of chromosomes are highly conserved in the genera Rana, Hyla and Bufo (Amphibia: Anura) (1995) Chromosoma, 103, pp. 567-574Morescalchi, A., Cytogenetics and the problem of lissamphibian relationships (1990) Cytogenetics of Amphibians and Reptiles, pp. 1-19. , Olmo, E. (ed.), Birkhäuser VerlagRabello, M.N., Chromosomal studies in brazilian anurans (1970) Caryologia, 23, pp. 45-59Raber, S.C., Caracterização cromossômica de Hyla bischoffi e Hyla guentheri (Anura, Hylidae) (2000), Master thesis. State Univ. of Campinas (UNICAMP), Campinas, SP, BrazilSchmid, M., Chromosome banding in Amphibia I. Constitutive heterochromatin and nucleolus organizers regions in Bufo and Hyla (1978) Chromosoma, 66, pp. 361-388Schmid, M., Chromosome banding in Amphibia. IV. Differentiation of GC and AT-rich chromosome regions in Anura (1980) Chromosoma, 77, pp. 83-103Schmid, M., Chromosome banding in Amphibia VII. Analysis of the structure and variability of NORs in Anura (1982) Chromosoma, 87, pp. 327-344Schmid, M., Almeida, C.G., Chromosome banding in Amphibia. XII. Restriction endonucleases banding (1988) Chromosoma, 96, pp. 283-290Schmid, M., Guttenbach, M., Evolutionary diversity of reverse (R) fluorescent chromosome bands in verlebrates (1988) Chromosoma, 97, pp. 101-114Schmid, M., Olert, J., Klett, C., Chromosome banding in Amphibia III. Sex chromosomes in Triturus (1979) Chromosoma, 71, pp. 29-55Skuk, G., Langone, J.A., Los cromosomas de cuatro especies del género Hyla (Anura: Hylidae) con número diploide de 2n = 30 (1992) Acta Zool. Lilloana, 41, pp. 165-171Sumner, A.T., A simple technique for demonstrating centromeric heterochromatin (1972) Exp. Cell Res., 75, pp. 304-30

Note on an extended chiral bosons system contextualized in a modified gauge-unfixing formalism

We analyze the Hamiltonian structure of an extended chiral bosons theory in which the self-dual constraint is introduced via a control $\alpha$-parameter. The system has two second-class constraints in the non-critical regime and an additional one in the critical regime. We use a modified gauge unfixing formalism to derive a first-class system, disclosing hidden symmetries. To this end, we choose one of the second-class constraints to build a corresponding gauge symmetry generator. The worked out procedure converts second-class variables into first-class ones allowing the lifting of gauge symmetry. Any function of these GU variables will also be invariant. We obtain the GU Hamiltonian and Lagrangian densities in a generalized context containing the Srivastava and Floreanini-Jackiw models as particular cases. Additionally, we observe that the resulting GU Lagrangian presents similarities to the Siegel invariant Lagrangian which is known to be suitable for describing chiral bosons theory with classical gauge invariance, however broken at quantum level. The final results signal a possible equivalence between our invariant Lagrangian obtained from the modified GU formalism and the Siegel invariant Lagrangian, with a distinct gauge symmetry.Comment: Revised version. To appear in EP

Modified gauge unfixing formalism and gauge symmetries in the non-commutative chiral bosons theory

We use the gauge unfixing (GU) formalism framework in a two dimensional noncommutative chiral bosons (NCCB) model to disclose new hidden symmetries. That amounts to converting a second-class system to a first-class one without adding any extra degrees of freedom in phase space. The NCCB model has two second-class constraints -- one of them turns out as a gauge symmetry generator while the other one, considered as a gauge-fixing condition, is disregarded in the converted gauge-invariant system. We show that it is possible to apply a conversion technique based on the GU formalism direct to the second-class variables present in the NCCB model, constructing deformed gauge-invariant GU variables, a procedure which we name here as modified GU formalism. For the canonical analysis in noncommutative phase space, we compute the deformed Dirac brackets between all original phase space variables. We obtain two different gauge invariant versions for the NCCB system and, in each case, a GU Hamiltonian is derived satisfying a corresponding first-class algebra. Finally, the phase space partition function is presented for each case allowing for a consistent functional quantization for the obtained gauge-invariant NCCB.Comment: 13 page

Gauge Symmetry of the Chiral Schwinger model from an improved Gauge Unfixing formalism

In this paper, the Hamiltonian structure of the bosonized chiral Schwinger model (BCSM) is analyzed. From the consistency condition of the constraints obtained from the Dirac method, we can observe that this model presents, for certain values of the $\alpha$ parameter, two second-class constraints, which means that this system does not possess gauge invariance. However, we know that it is possible to disclose gauge symmetries in such a system by converting the original second-class system into a first-class one. This procedure can be done through the gauge unfixing (GU) formalism by acting with a projection operator directly on the original second-class Hamiltonian, without adding any extra degrees of freedom in the phase space. One of the constraints becomes the gauge symmetry generator of the theory and the other one is disregarded. At the end, we have a first-class Hamiltonian satisfying a first-class algebra. Here, our goal is to apply a new scheme of embedding second-class constrained systems based on the GU formalism, named improved GU formalism, in the BCSM. The original second-class variables are directly converted into gauge invariant variables, called GU variables. We have verified that the Poisson brackets involving the GU variables are equal to the Dirac brackets between the original second-class variables. Finally, we have found that our improved GU variables coincide with those obtained from an improved BFT method after a particular choice for the Wess-Zumino terms.Comment: 13 page

Chromosome evolution in three Brazilian Leptodactylus species (Anura, Leptodactylidae), with phylogenetic considerations

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Karyotypic analyses on three species of the Leptodactylus from Brazil showed 2n=24 in L. cf. marmoratus, 2n=23 in Leptodactylus sp. (aff. bokermanni), and 2n=26 in L. hylaedactylus, with distinct numbers of bi and uni-armed chromosomes. Leptodactylus cf. marmoratus presented a variation as regard to the morphology of pair 12. All specimens of L. cf. marmoratus had Ag-NOR in pair 6, confirmed by FISH, but the sample from one of the localities presented additional Ag-NOR, in one of the chromosomes 8. In Leptodactylus sp. (aff. bokermanni) and L. hylaedactylus the chromosome pairs bearing Ag-NOR are 11 and 7, respectively. The C banding patterns are predominantly centromeric, but only in L. marmoratus this heterochromatin appeared very brilliant with DAPI. On the other hand, bright labelling was noticed with CMA(3) in the three species, on the Ag-NOR site. The data obtained here are in accordance with the proposed phylogeny to the genus, and the chromosomal analyses in these Leptodactylus showed that the karyotype evolution was based mainly in centric fusion and pericentric inversion.1462104111IBAMA [02010.000253/04-21, 02010-003315/05-38, 02010.002059/06-42]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Biodiversitas/CEPANFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)IBAMA [02010.000253/04-21, 02010-003315/05-38, 02010.002059/06-42

Gauging the SU(2) Skyrme model

In this paper the SU(2) Skyrme model will be reformulated as a gauge theory and the hidden symmetry will be investigated and explored in the energy spectrum computation. To this end we purpose a new constraint conversion scheme, based on the symplectic framework with the introduction of Wess-Zumino (WZ) terms in an unambiguous way. It is a positive feature not present on the BFFT constraint conversion. The Dirac's procedure for the first-class constraints is employed to quantize this gauge invariant nonlinear system and the energy spectrum is computed. The finding out shows the power of the symplectic gauge-invariant formalism when compared with another constraint conversion procedures present on the literature.Comment: revised version, to appear in Phys.Rev.

Multifunctional Lanthanide-Based Metal−Organic Frameworks Derived from 3‑Amino-4-hydroxybenzoate: Single-Molecule Magnet Behavior, Luminescent Properties for Thermometry, and CO2 Adsorptive Capacity

ACKNOWLEDGMENTS The authors thank SGIker of UPV/EHU and European funding (ERDF and ESF) for technical and human support as well as wish to acknowledge the terrific help of all reviewers of the present manuscript whose comments helped to improve the quality of the work.Supporting Information The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acs.inorgchem.2c00544.Funding E.E. is grateful to the Government of the Basque Country for the predoctoral fellowship and R.F.M. to the Junior Research Position CEECIND/ 00553/2017. The research contract of FF (REF-168-89-ARH/2018) is funded by national funds (OE), through FCT, in the scope of the framework contract foreseen in nos. 4, 5, and 6 of article 23 of the Decree-Law 57/2016, of 29 August, changed by Law 57/2017, of 19 July. This work was developed within the scope of the projects given by the Spanish Ministry of Science, Innovation and Universities (MCIU/AEI/ FEDER, UE) (PGC2018-102052-A-C22, PGC2018-102052-BC21, and PID2019-108028GB-C21), Gobierno Vasco/Eusko Jaurlaritza (IT1310-19 and IT1291-19), Junta de Andalucía (FQM-394), University of the Basque Country (GIU 20/028), and CICECO-Aveiro Institute of Materials (UIDB/50011/ 2020 and UIDP/50011/2020).Herein, we describe and study a new family of isostructural multifunctional metal–organic frameworks (MOFs) with the formula {[Ln5L6(OH)3(DMF)3]·5H2O}n (where (H2L) is 3-amino-4-hydroxybenzoic acid ligand) for magnetism and photoluminescence. Interestingly, three of the materials (Dy-, Er-, and Yb-based MOFs) present single-molecule magnet (SMM) behavior derived from the magnetic anisotropy of the lanthanide ions as a consequence of the adequate electronic distribution of the coordination environment. Additionally, photoluminescence properties of the ligand in combination with Eu and Tb counterparts were studied, including the heterometallic Eu–Tb mixed MOF that shows potential as ratiometric luminescent thermometers. Finally, the porous nature of the framework allowed showing the CO2 sorption capacity.Government of the Basque CountryJunior Research Position CEECIND/ 00553/2017National funds (OE)Spanish Ministry of Science, Innovation and Universities (MCIU/AEI/ FEDER, UE) (PGC2018-102052-A-C22, PGC2018-102052-BC21, and PID2019-108028GB-C21)Gobierno Vasco/Eusko Jaurlaritza (IT1310-19 and IT1291-19)Junta de Andalucía (FQM-394)University of the Basque Country (GIU 20/028)CICECO-Aveiro Institute of Materials (UIDB/50011/ 2020 and UIDP/50011/2020

Multifunctionality in an Ion-Exchanged Porous Metal-Organic Framework

Porous robust materials are typically the primary selection of several industrial processes. Many of these compounds are, however, not robust enough to be used as multifunctional materials. This is typically the case of Metal-Organic Frameworks (MOFs) which rarely combine several different excellent functionalities into the same material. In this report we describe the simple acid-base postsynthetic modification of isotypical porous rare-earth-phosphonate MOFs into a truly multifunctional system, maintaining the original porosity features: [Ln(H3pptd)]·xSolvent [where Ln3+ = Y3+ (1) and (Y0.95Eu0.05)3+ (1_Eu)] are converted into [K3Ln(pptd)]·zSolvent [where Ln3+ = Y3+ (1K) and (Y0.95Eu0.05)3+ (1K_Eu)] by immersing the powder of 1 and 1_Eu into an ethanolic solution of KOH for 48 h. The K+-exchanged Eu3+-based material exhibits a considerable boost in CO2 adsorption, capable of being reused for several consecutive cycles. It can further separate C2H2 from CO2 from a complex ternary gas mixture composed of CH4, CO2, and C2H2. This high adsorption selectivity is, additionally, observed for other gaseous mixtures, such as C3H6 and C3H8, with all these results being supported by detailed theoretical calculations. The incorporation of K+ ions notably increases the electrical conductivity by 4 orders of magnitude in high relative humidity conditions. The conductivity is assumed to be predominantly protonic in nature, rendering this material as one of the best conducting MOFs reported to date.publishe