Vacuum stability conditions of the economical 3-3-1 model from copositivity

By applying copositivity criterion to the scalar potential of the economical $3-3-1$ model, we derive necessary and sufficient bounded-from-below conditions at tree level. Although these are a large number of intricate inequalities for the dimensionless parameters of the scalar potential, we present general enlightening relations in this work. Additionally, we use constraints coming from the minimization of the scalar potential by means of the orbit space method, the positivity of the squared masses of the extra scalars, the Higgs boson mass, the $Z'$ gauge boson mass and its mixing angle with the SM $Z$ boson in order to further restrict the parameter space of this model.Comment: 22 pages, 7 figures, added text and references. Matches published versio

Relaxation behavior of semiflexible polymers at very low frequencies

[EN] The dielectric activity of poly(monocyclohexylmethylene itaconate) (PMCI) and poly(dicyclohexylmethylene itaconate) (PDCI) in the glassy region and in the glass-rubber transition is studied by thermostimulated discharge current (TSDC) techniques. The spectra obtained by global TSDC experiments show a prominent alpha-glass-rubber relaxation peak with maxima located at 97 and 55 degrees C for PMCI and PDCI, respectively, following in decreasing order of temperature for a well developed beta absorption and a comparatively low intensity relaxation. Better resolution of the relaxation behavior of these polymers in the glassy region is obtained by calculating the components of the complex dielectric permittivity epsilon* at extremely low frequencies from partial TSDC experiments. The ac spectra thus obtained suggest that the beta absorption is composed by two relaxations, each of them presumably associated with the motions of a side group. The differences observed in these spectra with those reported for the beta mechanical relaxation reported for these polymers in the literature are interpreted in terms of the restrictions that the side groups produce in the conformational space of phase of the backbone. These restrictions also explain the small changes in enthalpy in the glass-rubber transition which preclude the possibility of obtaining the glass-rubber transition temperature of these polymers by differential scanning calorimetric techniques. (C) 1997 American Institute of Physics.Díaz Calleja, R.; Sanchis Sánchez, MJ.; Alvarez, C.; Riande, E. (1997). Relaxation behavior of semiflexible polymers at very low frequencies. Journal of Applied Physics. 81(8):3685-3691. doi:10.1063/1.364743S3685369181

Integrable theories and loop spaces: fundamentals, applications and new developments

We review our proposal to generalize the standard two-dimensional flatness construction of Lax-Zakharov-Shabat to relativistic field theories in d+1 dimensions. The fundamentals from the theory of connections on loop spaces are presented and clarified. These ideas are exposed using mathematical tools familiar to physicists. We exhibit recent and new results that relate the locality of the loop space curvature to the diffeomorphism invariance of the loop space holonomy. These result are used to show that the holonomy is abelian if the holonomy is diffeomorphism invariant. These results justify in part and set the limitations of the local implementations of the approach which has been worked out in the last decade. We highlight very interesting applications like the construction and the solution of an integrable four dimensional field theory with Hopf solitons, and new integrability conditions which generalize BPS equations to systems such as Skyrme theories. Applications of these ideas leading to new constructions are implemented in theories that admit volume preserving diffeomorphisms of the target space as symmetries. Applications to physically relevant systems like Yang Mills theories are summarized. We also discuss other possibilities that have not yet been explored.Comment: 64 pages, 8 figure

Angular emission properties of a layer of rare-earth based nanophosphors embedded in one-dimensional photonic crystal coatings

The angular properties of light emitted from rare-earth based nanophosphors embedded in optical resonators built in one-dimensional photonic crystal coatings are herein investigated. Strong directional dependence of the photoluminescence spectra is found. Abrupt angular variations of the enhancement caused by the photonic structure and the extraction power are observed, in good agreement with calculated polar emission patterns. Our results confirm that the optical cavity favors the extraction of different wavelengths at different angles and that integration of nanophosphors within photonic crystals provides control over the directional emission properties that could be put into practice in phosphorescent displays.Ministerio de Ciencia e Innovación MAT2008- 02166, CSD2007-00007Junta de Andalucía FQM3579, FQM524

Abrogation of mercuric chloride-induced nephritis in the Brown Norway rat by treatment with antibodies against TNFα

HgCl2 induces an autoimmune disease in the Brown Norway rat characterized by synthesis of autoantibodies (mainly, anti-GBM Abs), severe proteinuria and interstitial nephritis. Also, HgCl2- injected rats develop glomerular cell infiltrates consisting of ED1+ cells (monocyte/macrophage), starting on day 4 and reaching a maximum on day 8. Treatment with anti-TNF-α antiserum had preventative effects as it reduced the urinary protein levels to close to the normal range and also blocked the influx of inflammatory cells in the renal glomeruli and interstitium, but circulating anti-GBM and lineal glomerular IgG deposits were unmodified. In addition, whole isolated glomeruli from HgCl2-induced nephritis secreted TNF-α commencing on day 8, being maximally detected on day 11 and preceding, between 2 to 3 days, the development of proteinuria. The administration of anti-TNF-α antiserum or anti-α4 integrin mAb completely abrogated the synthesis of TNF-α in glomeruli isolated from the respective treated groups of animals, in addition to the proteinuria. Taken together our results confirm that TNF-α plays an important role in the induction and development of HgCl2-induced nephritis and highlights the pathogenic importance of the local release of TNF in those renal diseases in which prominent glomerular macrophage accumulation is a constant feature

Autofluorescence of stingray skeletal cartilage: hyperspectral imaging as a tool for histological characterization

Tessellated cartilage is a distinctive composite tissue forming the bulk of the skeleton of cartilaginous fishes (e.g. sharks and rays), built from unmineralized cartilage covered at the surface by a thin layer of mineralized tiles called tesserae. The finescale structure and composition of elasmobranch tessellated cartilage has largely been investigated with electron microscopy, micro-computed tomography and histology, but many aspects of tissue structure and composition remain uncharacterized. In our study, we demonstrate that the tessellated cartilage of a stingray exhibits a strong and diverse autofluorescence, a native property of the tissue which can be harnessed as an effective label-free imaging technique. The autofluorescence signal was excited using a broad range of wavelengths in confocal and light sheet microscopy, comparing several sample preparations (fresh; demineralized and paraffin-embedded; non-demineralized and plastic-embedded) and imaging the tissue at different scales. Autofluorescence varied with sample preparation with the signal in both plastic- and paraffin-embedded samples strong enough to allow visualization of finescale (≥ 1 μm) cellular and matrix structures, such as cell nuclei and current and former mineralization fronts, identifiable by globular mineralized tissue. A defined pericellular matrix (PCM) surrounding chondrocytes was also discernible, described here for the first time in elasmobranchs. The presence of a PCM suggests similarities with mammalian cartilage regarding how chondrocytes interact with their environment, the PCM in mammals acting as a transducer for biomechanical and biochemical signals. A posterior analysis of hyperspectral images by an MCR-ALS unmixing algorithm allowed identification of several distinct fluorescence signatures associated to specific regions in the tissue. Some fluorescence signatures identified could be correlated with collagen type II, the most abundant structural molecule of cartilage. Other fluorescence signatures, however, remained unidentified, spotlighting tissue regions that deserve deeper characterization and suggesting the presence of molecules still unidentified in elasmobranch skeletal cartilage. Our results show that autofluorescence can be a powerful exploratory imaging tool for characterizing less-studied skeletal tissues, such as tessellated cartilage. The images obtained are largely comparable with more commonly used techniques, but without the need for complicated sample preparations or external staining reagents standard in histology and electron microscopy (TEM, SEM)

Lactoinducción en novillas.

En el Centro de Investigaciones Tibaitatá, Cundinamarca se realizó un ensayo para evaluar la inducción hormonal de lactancias en novillas lecheras sin problemas reproductivos. Se utilizaron 14 novillas Holstein las cuales fueron sometidas a 2 tratamientos: tratamiento 1, progesterona de absorción normal, estrógenos, dexametasona y oxitocina. Y tratamiento 2, progesterona de depósito, estrógenos, dexametasona y oxitocina. Adicionalmente, se conformó un grupo testigo de 7 novillas preñadas, con parto durante la época de los tratamientos hormonales. El manejo, alimentación y suplementación fueron similares en todos los animales. El éxito de inducción láctea fue mayor para el tratamiento 1 respecto al tratamiento 2 (100 por ciento vs. 71.2 por ciento P mayor de 0.05). La producción láctea obtenida en los animales experimentales fue aceptable (7.8 litros/animal/día), sin presentarse diferencias entre tratamientos (7.71 vs 7.91). El pico de producción en animales experimentales se presentó a las 9.5 semanas, y la longitud de la lactancia promedio 279 dias. Aunque inicialmente se presentaron quistes ováricos en los animales experimentales, éstos no afectaron el comportamiento reproductivo, presentándose el 83 por ciento de preñez a los 180 dias. El crecimiento no fue afectado por la lactancia inducida. Los tratamientos hormonales fueron rentables, al tener en cuenta la tasa de retorno (1.71 y 1.76 respectivamente

Insulin protects acinar cells during pancreatitis by preserving glycolytic ATP supply to calcium pumps.

From Europe PMC via Jisc Publications RouterHistory: ppub 2021-07-01, epub 2021-07-19Publication status: PublishedFunder: Medical Research Council; Grant(s): MR/P00251X/1Funder: NIDDK NIH HHS; Grant(s): P30 DK089503, R01 DK059578, P30 DK020572, P60 DK020572, U2C DK110768Funder: Wellcome TrustAcute pancreatitis (AP) is serious inflammatory disease of the pancreas. Accumulating evidence links diabetes with severity of AP, suggesting that endogenous insulin may be protective. We investigated this putative protective effect of insulin during cellular and in vivo models of AP in diabetic mice (Ins2Akita) and Pancreatic Acinar cell-specific Conditional Insulin Receptor Knock Out mice (PACIRKO). Caerulein and palmitoleic acid (POA)/ethanol-induced pancreatitis was more severe in both Ins2Akita and PACIRKO vs control mice, suggesting that endogenous insulin directly protects acinar cells in vivo. In isolated pancreatic acinar cells, insulin induced Akt-mediated phosphorylation of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 2 (PFKFB2) which upregulated glycolysis thereby preventing POA-induced ATP depletion, inhibition of the ATP-dependent plasma membrane Ca2+ ATPase (PMCA) and cytotoxic Ca2+ overload. These data provide the first mechanistic link between diabetes and severity of AP and suggest that phosphorylation of PFKFB2 may represent a potential therapeutic strategy for treatment of AP

Arteriovenous uterine malformation: case report

The case of a 49-year-old patient is reported, with a particular history of obstetric risk, who presented with severe transvaginal hemorrhage, was performed doppler arteriography and ultrasound, finding data suggestive of arteriovenous uterine malformation, surgery was decided due to heavy menstrual bleeding with anemia, the pathology report shows characteristics of an arteriovenous uterine malformation