Coulomb-type interaction under Lorentz symmetry breaking effects

Based on models of confinement of quarks, we analyse a relativistic scalar particle subject to a scalar potential proportional to the inverse of the radial distance and under the effects of the violation of the Lorentz symmetry. We show that the effects of the Lorentz symmetry breaking can induced a harmonic-type potential. Then, we solve the Klein-Gordon equation analytically and discuss the influence of the background of the violation of the Lorentz symmetry on the relativistic energy levels.Comment: 10 pages, no figur

Upaya Meningkatkan Kemandirian Belajar Siswa melalui Lesson Study di Kelas V SD Negeri Lampageu Aceh Besar

Dalam konteks interaksi belajar mengajar di kelas siswa kurag mandiri, penelitian ini berupaya mengungkapkan upaya peningkatan kemandirian belajar siswa melalui lesson study. Secara khusus penelitian ini bertujuan (1) untuk mengetahui peningkatan kemandirian belajar siswa melalui lesson study di kelass V SD Negeri Lampageu Aceh Besar dan (2) untuk mengetahui aktifitas siswa dan guru dalam proses pembelajaran melalui lesson study di kelas V SD Negeri Lampageu Aceh Besar. Subjek penelitian ini adalah siswa kelas V SD Negeri Lampageu Aceh Besar, sebanyak 15 siswa yang terdiri dari 6 siswa laki-laki dan 9 siswa perempuan. Pelaksanaan lesson study dimulai dari tanggal 05 september 2016 sampai 19 september 2016. Jenis penelitian ini deskriptif dengan menggunakan pendekatan kualitatif, pengumpulan data dilakukan melalui teknik observasi aktifitas siswa dan wawancara guru. Teknik pengumpulan data menggunakan statistic sederhana untuk melihat atau mencari nilai rata-rata jawaban responden. Berdasarkan hasil analisis data observasi belajar siswa memperoleh nilai rata-rata pada pertemuan pertama sebanyak 2,896, kedua 3,413, dan ketiga sebanyak 3,6928. Analisis nilai rata-rata sudah ada peningkatan kemandirian belajar siswa pada setiap pertemuan. Hasil wawancara menunjukkan bahwa siswa senang dan sangat bersemangat dengan kegiatan pembelajaran yang dilakukan. Kesimpulan penelitian ini menunjukkan bahwa siswa kelas V SD Negeri Lampageu Aceh Besar sangat antusias dan bersemangat, sehingga interaksi proses belajar mengajar dapat berlangsung seperti yang diharapkan

Pelaksanaan Penilaian Hasil Belajar Siswa pada Sub Tema Hidup Rukun dengan Teman Bermain di Kelas II Sdn 14 Banda Aceh

Penelitian ini berjudul pelaksanaan penilaian hasil belajar siswa pada subtema hidup rukun dengan teman bermain di kelas II Sekolah Dasar Negeri 14 Banda Aceh. Adapun rumusan masalah penelitian ini adalah bagaimana pelaksanaan penilaian hasil belajar siswa pada subtema hidup rukun dengan teman bermain di kelas II Sekolah Dasar Negeri 14 Banda Aceh. Penelitian ini bertujuan untuk mengetahui pelaksanaan penilaian hasil belajar siswa pada subtema hidup rukun dengan teman bermain di kelas II Sekolah Dasar Negeri 14 Banda Aceh. Subjek dalam penelitian ini adalah guru kelas II pada tahun ajaran 2016-2017 yaitu 1 orang. Pendekatan yang digunakan dalam penelitian ini adalah pendekatan kualitatif dengan jenis penelitian deskriptif. Pengumpulan data dilakukan dengan teknik observasi dan dokumentasi. Berdasarkan hasil analisis data yang diperoleh dari penelitian ini adalah berupa lembaran pengamatan yang peneliti amati mengenai pelaksanaan penilaian hasil belajar siswa oleh guru selama berlangsungnya proses belajar mengajar. Kegiatan observasi ini dilakukan selama 6 hari pada 6 pembelajaran berdasarkan subtema Hidup Rukun dengan Teman Bermain.Simpulan penelitian ini adalah penilaian menuntut guru agar secara langsung maupun tidak, mampu melaksanakan penilaian dalam keseluruhan proses pembelajaran guna untuk menilai sejauh mana siswa telah menguasai beragam kompetensi. Pelaksanaan penilaian hasil belajar siswa pada tema Hidup Rukun dengan subtema Hidup Rukun dengan Teman Bermain pada kelas II Sekolah Dasar Negeri 14 Banda Aceh pelaksanaan penilaian sikap, pengetahuan dan keterampilan sudah terlaksana dengan Kurikulum 2013

Feshbach-Villars oscillator (FVO) in Kaluza-Klein Theory (KKT)

This research investigates the relativistic quantum dynamics of spin-0 scalar massive charged particles via the relativistic Feshbach-Villars oscillator in the background of the Kaluza-Klein Theory. We solve the Feshbach-Villars equation in the abckground of a cosmic string spec-time in the context of the Kaluza-Klein and presented the eigenvalue solution. Afterward, we rewrite this system in the case of the Feshbach-Villars quantum oscillator and obtain the eigenvalue analytically. Finally, we study the interaction of the Feshbach-Villars equation and oscillator in a cosmic dislocation in the Som-Raychaudhuri in the context of the Kaluza-Klein Theory and solve the wave equation analytically. We analyze the influence of topological defect in the quantification of energy and wave function of the Feshbach-Villars oscillator and with the external fields in the last oneComment: arXiv admin note: text overlap with arXiv:2304.12496 (Accepted for publication In Nuclear Physics B

Flat ring epimorphisms and universal localizations of commutative rings

We study different types of localizations of a commutative noetherian ring. More precisely, we provide criteria to decide: (a) if a given flat ring epimorphism is a universal localization in the sense of Cohn and Schofield; and (b) when such universal localizations are classical rings of fractions. In order to find such criteria, we use the theory of support and we analyse the specialization closed subset associated to a flat ring epimorphism. In case the underlying ring is locally factorial or of Krull dimension one, we show that all flat ring epimorphisms are universal localizations. Moreover, it turns out that an answer to the question of when universal localizations are classical depends on the structure of the Picard group. We furthermore discuss the case of normal rings, for which the divisor class group plays an essential role to decide if a given flat ring epimorphism is a universal localization. Finally, we explore several (counter)examples which highlight the necessity of our assumptions

Assessment of the effect of a new technique for laparoscopic partial closure of the inguinal canal on sperm production and testicular perfusion in stallions

In order to simplify other laparoscopic techniques, a new standing laparoscopic technique for partial closure of inguinal canal (PCIC) has been developed. This technique uses a new anchoring device and can be performed without advanced laparoscopic skills. The aim of this study was to develop a prior evaluation of the effects of this new technique on the stallion reproductive capacity, assessing the sperm production and testicular perfusion. Standing laparoscopic PCIC was performed unilaterally in 8 experimental stallions without evidence of inguinal hernia, using the contralateral canal and testicle as control

Humoral immune response against allogeneic equine mesenchymal stem cells (MSCs) mediated by the major histocompatibility complex (MHC): an issue to take into account for the safety and efficacy of treatment with MSCs

Allogeneic mesenchymal stem cells (MSCs) present several advantages, but recipient immune response needs to be further elucidated. Proinflammatory priming of MSCs activated their in vivo regulatory capacity, but repeated administrations led to slight inflammatory reaction in an osteoarthritis equine model. This may be associated with higher major histocompatibility complex (MHC) expression, which would increase MSC immunogenicity potentially inducing humoral mediated immune memory. This study aimed at assessing allo-antibody production against donor’s equine MHC (equine leukocyte antigen, ELA) in animals that received intra-articular repeated administration of allogeneic MSC-primed. For this purpose, we used stored samples from a previous study. Donor and recipients ELA-haplotypes were stablished by microsatellite typing and complementmediated microcytoxicity assays were carried out by exposing target cells from the donor (unstimulated MSCs [MSC-nai¨ve], MSC-primed or lymphocytes [control]) to sera collected at different time-points from 10 recipients: ELA-mismatched MSCnai ¨ve recipients, ELA-mismatched MSC-primed recipients or ELA-partially matched MSC-primed recipients. All animals receiving allogeneic MSCs produced allo-antibodies after the first injection, regardless of the matching degree. However, antibody peak production after second administration was only observed in ELA-mismatched recipients, both of MSC-nai¨ve and MSCprimed. Horses injected with MSC-primed produced fewer antibodies but MSC-primed were more targeted in the microcytoxicity assay. Thus, activated immunomodulatory profile of MSC-primed could have led to slighter humoral response after ..

Characterization of green composites from biobased epoxy matrices and bio-fillers derived from seashell wastes

The seashells, a serious environmental hazard, are composed mainly by calcium carbonate, which can be used as filler in polymer matrix. The main objective of this work is the use of calcium carbonate from seashells as a bio-filler in combination with eco-friendly epoxy matrices thus leading to high renewable contents materials. Previously obtaining calcium carbonate, the seashells were washed and grinded. The powder obtained and the resin was characterized by DSC, TGA, X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), and rheology plate-plate. The results show that addition of 30 wt.% of seashell bio-filler increase mechanical properties as flexural modulus (over 50%) and hardness Shore D (over 6%) and thermal properties as an increase around 13% in glass transitions temperature. The results show that the addition of calcium carbonate from seashells is an effective method to increase mechanical properties of bio-composite and to reduce the residue of seashells from industrial production. (C) 2013 Elsevier Ltd. All rights reserved.L. Bernardi would like to thank CNPq, Consejo Nacional de Desenvolvimiento Cientifico y Tecnologico - Brasil for financial support through a scholarship number.Fombuena Borrás, V.; Bernardi, L.; Fenollar Gimeno, OÁ.; Boronat Vitoria, T.; Balart Gimeno, RA. (2014). Characterization of green composites from biobased epoxy matrices and bio-fillers derived from seashell wastes. Materials and Design. 57:168-174. doi:10.1016/j.matdes.2013.12.0321681745

A systematic review on the ecosystem services provided by green infrastructure

Urbanization and climate change are endangering the sustainability of public spaces through increased land artificialization, ecological fragmentation, reduced resource availability, and limited accessibility to natural and seminatural areas. Properly managing Green Infrastructure (GI) can contribute to mitigating these challenges by delivering multiple provisioning, regulating, supporting and cultural Ecosystem Services (ES). This would facilitate the implementation of strategically planned GI networks in cities for urban regeneration purposes. In this context, this study developed a systematic review on the ES provided by GI using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The analysis of 199 eligible articles indicated that more efforts should be made to address more ES at once, which connects to the need for conceiving GI as a strategically planned network of areas aimed at delivering diverse benefits. Based on the methods used in the items reviewed, geoprocessing tools and multi-criteria decision analysis are proposed to develop systems of indicators capable of accounting for multiple ES. These systems should also rely on multidisciplinary and participative procedures to encompass various facets of GI and represent the priorities of all relevant stakeholders