Dynamical Casimir effect with Robin boundary conditions in a three dimensional open cavity

We consider a massless scalar field in 1+1 dimensions inside a cavity composed by a fixed plate, which imposes on the field a Robin BC, and an oscillating one, which imposes on the field a Dirichlet BC. Assuming that the plate moves for a finite time interval, and considering parametric resonance, we compute the total number of created particles inside the cavity. We generalize our results to the case of two parallel plates in 3+1 dimensions.Comment: This work was presented in the Conference QFEXT09, held at the University of Oklahoma, Norman, OK, USA, September 21-25, 2009, and will appear in the proceedings of this conference. It contains 4 figure

Estimative for the size of the compactification radius of a one extra dimension Universe

In this work, we use the Casimir effect to probe the existence of one extra dimension. We begin by evaluating the Casimir pressure between two plates in a $M^4\times S^1$ manifold, and then use an appropriate statistical analysis in order to compare the theoretical expression with a recent experimental data and set bounds for the compactification radius

Instabilities and propagation of neutrino magnetohydrodynamic waves in arbitrary direction

In a previous work [16], a new model was introduced, taking into account the role of the Fermi weak force due to neutrinos coupled to magnetohydrodynamic plasmas. The resulting neutrino-magnetohydrodynamics was investigated in a particular geometry associated with the magnetosonic wave, where the ambient magnetic field and the wavevector are perpendicular. The corresponding fast, short wavelength neutrino beam instability was then obtained in the context of supernova parameters. The present communication generalizes these results, allowing for arbitrary direction of wave propagation, including fast and slow magnetohydrodynamic waves and the intermediate cases of oblique angles. The numerical estimates of the neutrino-plasma instabilities are derived in extreme astrophysical environments where dense neutrino beams exist

Pengaruh Penyuluhan Imunisasi Campak Terhadap Peningkatan Pengetahuan Dan Sikap Ibu

Latar Belakang: Imunisasi sebagai salah satu cara preventif untuk mencegah penyakit melalui pemberia kekebalan tubuh yang harus diberikan secara menyeluruh. Oleh sebab itu penting adanya mobilisasi masyarakat dalam hal pemberian penyuluhan kesehatan mengenai imunisasi campak agar orang tua memahami benar manfaat imunisasi campak1.Tujuan: Penelitian ini bertujuan untuk mengetahui apakah ada pengaruh penyuluhan imunisasi campak terhadap peningkatan pengetahuan da sikap ibu di Puskesmas Tuminting Kecamatan Tuminting Kota Manado.Metode : Jenis penelitian ini adalah penelitian quasi eksperimen yaitu suatu penelitian yang melakukan kegiatan percobaan untuk mengetahui gejala yang timbul dari perlakuan tertentu. Eksperimen dilakukan tanpa kelompok pembanding. Jumlah sampel 60 orang. Pengumpulan data dilakukan dengan cara memberikan perlakuan yaitu kepada ibu-ibu yang memiliki anak usia 11-24 bulan menggunakan metode penyuluhan kesehatan. Analisis data dengan menggunakan uji Paired Samples T-Test.Hasil : Menunjukkan tingkat pengetahuan sebelum diberikan penyuluhan kesehatan paling besar pada kategori kurang sebesar 71,7% dan setelah diberikan penyuluhan tingkat pengetahuan responden paling besar ada pada kategori baik sebesar 51,7%. Analisa data menunjukkan signifikansi ( 0,0001 ) lebih kecil dari 0,05 ( α ). Sedangkan sikap sebelum diberikan penyuluhan paling besar ada pada kategori kurang ( 56,7%), dan setelah dberikan penyuluhan sikap responden paling besar ada pada kategori baik sebesar ( 80% ). Analisa data menunjukkan signifikansi ( 0,0001 ) lebih kecil dari 0,05 ( α )

Torsion and Inflammation of Meckel's Diverticulum: Rare Cause of Acute Abdominal Pain

Meckel's diverticulum is a remnant of the embryologic vitelline duct. It was named after its anatomical and embryological description, in the early 19th century, by Johann Meckel. It is known as a true diverticulum of the small bowel and is typically estimated to be present in 2% of the general population, with only a very small percentage being symptomatic. In this report, we present a 14-year-old boy with complaints of abdominal pain, fever, nausea, vomiting and diarrhea. During physical examination we observed peritoneal irritation and raised inflammatory markers. Surgical exploration revealed torsion and inflammation of a large Meckel's diverticulum with a gangrenous area. In order to ensure the removal of etopic tissue, if present, segmental bowel resection with primary anastomosis was performed. Histopathological analysis did not find ectopic tissue. The operative and postoperative courses were uneventful. Meckel's diverticulum is an important differential diagnosis in acute abdominal pain in children.info:eu-repo/semantics/publishedVersio

Effects of intrapopulation phenotypic traits of invasive crayfish on leaf litter processing

The impact of invasive alien species (IAS) on an ecosystem is primarily studied at the species level, whereas the functional impacts of their genetic and phenotypic traits are poorly investigated. We used two laboratory based experiments to assess how intrapopulation phenotypic traits (size, sex, and number of claws) of the invasive red swamp crayfish Procambarus clarkii affect invertebrate shredders and leaf processing. Leaf consumption was significantly affected by the size and number of claws but not by the sex of the crayfish. Bigger animals presented a higher overall consumption but, in contrast, the mass of leaves consumed per unit crayfish body mass decreased with size. Indeed, the production of particulate organic matter followed the same trend, suggesting that the higher metabolic needs of smaller animals are responsible for their higher feeding activity on leaf litter. Claw loss in P. clarkii also led to increased leaf consumption and may be related to increased energy requirements for claw regeneration. Our results highlight the importance of also considering the phenotypic traits within populations for better understanding the impacts of IAS on ecosystem processes.This work was supported by the strategic programme UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) and the FreshBioFun project (PTDC/AAC-AMB/117068/2010) funded by the Portuguese Foundation for Science and Technology (FCT), by the Ministerio da Ciencia, Tecnologia e Ensino Superior (MCTES) and by the European Regional Development Fund (ERDF) through the COMPETE2020 - Programa Operacional Competitividade e Internacionalizacao (POCI). We acknowledge the anonymous referees and the editor for their constructive suggestions and our colleague Tony Collins for the English revision

Determination of the Hydroxy and Carboxylic Acid Groups in Natural Complex Mixtures of Hydroxy Fatty Acids by (1)H Nuclear Magnetic Resonance Spectroscopy

The use of trichloroacetyl isocyanate (TAI) to mark both hydroxyl and carboxyl groups borne by the hydrolysis or methanolysis of suberin fragments (a complex mixture of hydroxy fatty acids), allowed the quantitative assessment of the ratio between carboxyl and hydroxy groups, as well as the ratio between primary and secondary hydroxy groups, to be carried out reliably by (1)H nuclear magnetic resonance (NMR) spectroscopy. All the samples thus analyzed displayed an excess of CO(2)H (or CO(2)CH(3)) functions with respect to the OH counterparts, albeit to a variable extent, depending on the procedure adopted to isolate the suberin fragments. The precise knowledge of the molar ratio of these two reactive moieties is fundamental for the correct utilization of suberin monomers in polymerization reactions leading to aliphatic polyesters.FCT - SFRH/ BD/38890/200

Temperature inversion symmetry in the Casimir effect with an antiperiodic boundary condition

We present explicitly another example of a temperature inversion symmetry in the Casimir effect for a nonsymmetric boundary condition. We also give an interpretation for our result.Comment: 4 page