Wave Equations for Classical Two-Component Proca Fields in Curved Spacetimes with Torsionless Affinities

The world formulation of the full theory of classical Proca fields in generally relativistic spacetimes is concisely reviewed and the entire set of pertinent field equations is transcribed in a straightforward way into the framework of one of the Infeld-van der Waerden formalisms. Some well-known calculational techniques are then utilized for deriving the wave equations that control the propagation of the fields allowed for. It appears that no interaction couplings between such fields and electromagnetic curvatures are carried by the wave equations at issue. What results is, in effect, that the only interactions which ultimately occur in the theoretical context under consideration involve strictly Proca fields and wave functions for gravitons.Comment: Many improvements on the paper have still been made. In particular, its title has been modified so as to conform further to one of its main aim

New family of potentials with analytical twiston-like solutions

In this letter we present a new approach to find analytical twiston models. The effective two-field model was constructed by a non-trivial combination of two one field systems. In such an approach we successfully build analytical models which are satisfied by a combination of two defect-like solutions, where one is responsible to twist the molecular chain by $180^{\,0}$, while the other implies in a longitudinal movement. Such a longitudinal movement can be fitted to have the size of the distance between adjacent molecular groups. The procedure works nicely and can be used to describe the dynamics of several other molecular chains.Comment: 7 pages, 3 figure

New XMM-Newton observation of the Phoenix cluster: properties of the cool core

(Abridged) We present a spectral analysis of a deep (220 ks) XMM-Newton observation of the Phoenix cluster (SPT-CL J2344-4243), which we also combine with Chandra archival ACIS-I data. We extract CCD and RGS X-ray spectra from the core region to search for the signature of cold gas, and constrain the mass deposition rate in the cooling flow which is thought to be responsible of the massive star formation episode observed in the BCG. We find an average mass deposition rate of $\dot M = 620 (-190 +200)_{stat} (-50 +150)_{syst} M_\odot$/yr in the temperature range 0.3-3.0 keV from MOS data. A temperature-resolved analysis shows that a significant amount of gas is deposited only above 1.8 keV, while upper limits of the order of hundreds of $M_\odot$/yr can be put in the 0.3-1.8 keV temperature range. From pn data we obtain $\dot M = 210 (-80 +85)_{stat} ( -35 +60)_{syst} M_\odot$/yr, and the upper limits from the temperature-resolved analysis are typically a factor of 3 lower than MOS data. In the RGS spectrum, no line emission from ionization states below Fe XXIII is seen above $12 \AA$, and the amount of gas cooling below $\sim 3$ keV has a best-fit value $\dot M = 122_{-122}^{+343}$ $M_{\odot}$/yr. In addition, our analysis of the FIR SED of the BCG based on Herschel data provides $SFR = (530 \pm 50) M_\odot$/yr, significantly lower than previous estimates by a factor 1.5. Current data are able to firmly identify substantial amount of cooling gas only above 1.8 keV in the core of the Phoenix cluster. While MOS data analysis is consistent with values as high as $\dot M \sim 1000$ within $1 \sigma$, pn data provide $\dot M < 500 M_\odot$ yr$^{-1}$ at $3\sigma$ c.l. at temperature below 1.8 keV. At present, this discrepancy cannot be explained on the basis of known calibration uncertainties or other sources of statistical noise.Comment: A&A in press, typos corrected, revised text according to published versio

Light elements in stars with exoplanets

It is well known that stars orbited by giant planets have higher abundances of heavy elements when compared with average field dwarfs. A number of studies have also addressed the possibility that light element abundances are different in these stars. In this paper we will review the present status of these studies. The most significant trends will be discussed.Comment: 10 pages, 6 figures. Submitted to the proceedings of IAU symposium 268: Light elements in the universe

Entanglement and Bell's inequality violation above room temperature in metal carboxylates

In the present work we show that a special family of materials, the metal carboxylates, may have entangled states up to very high temperatures. From magnetic susceptibility measurements, we have estimated the critical temperature below which entanglement exists in the cooper carboxylate \{Cu$_2$(O$_2$CH)$_4$\}\{Cu(O$_2$CH)$_2$(2-methylpyridine)$_2$\}, and we have found this to be above room temperature ($T_e \sim 630$ K). Furthermore, the results show that the system remains maximally entangled until close to $\sim 100$ K and the Bell's inequality is violated up to nearly room temperature ($\sim 290$ K)

Regulação da produção da eritropoietina e perspectivas terapêuticas na anemia

About 30 years ago, the treatment of chronic renal disease anaemia was revolutionized by the introduction of recombinant human erythropoietin, which reduced the need for blood transfusions. In spite of this huge advance, the first recombinant human erythropoietin has a relatively short half-life and needs to be administered two to three times per week. Subsequently, other molecules were developed, such as darbepoetin alfa, continuous erythropoietin receptor activator (CERA) and peginesatide, with longer half-life, but the route of administration still remains a problem. Erythropoietin has an action that exceeds erythropoiesis and plays an important role in cell protection. Based on knowledge of the molecular mechanisms that control erythropoiesis, namely the regulation of EPO gene expression, through HIF system, GATA-2 and NF-kB, several upcoming therapeutic agents and strategies for stimulating and treating anaemia emerged. The main effort in developing these treatments is to achieve other routes of administration, more convenient for the patient, such as oral therapy, not disregarding an easier production, storage and frequency of administration. Some of them are still in laboratory phase and others already in clinical trials phase II or III. In this work, based on a literature search of studies using MEDLINE, our objective is to review the regulation of erythropoietin production and its functions, as well as treatment approach for anaemia of chronic kidney disease, with particular focus on new therapiesHá cerca de 30 anos atrás, o tratamento da anemia da doença renal crónica foi revolucionado pela introdução da eritropoietina (EPO) humana recombinante que permitiu reduzir drasticamente a necessidade de transfusões sanguíneas. Apesar deste grande avanço, a primeira EPO humana recombinante tem uma semivida relativamente curta e tem de ser administrada duas a três vezes por semana. Subsequentemente, foram desenvolvidas outras moléculas, como a darbepoetina alfa, o ativador contínuo do EPO-R (CERA) e o peginesatide, com uma semivida mais longa, mas a via de administração continua a ser exclusivamente parenteral. A eritropoietina desempenha várias funções além da eritropoiética. Tendo por base os mecanismos moleculares que controlam a eritropoiese, nomeadamente a regulação da expressão do gene da EPO, através do sistema do HIF, GATA-2 e NF-kB, surgiram vários fármacos e estratégias terapêuticas para o tratamento da anemia. O principal objetivo destes novos tratamentos passa por desenvolver outras vias de administração, mais cómodas para o doente, como a terapia oral, e facilitar a produção, armazenamento e frequência de administração dos fármacos. Alguns destes ainda se encontram em fase laboratorial, enquanto outros já estão em ensaios clínicos fase II ou III. Neste trabalho, baseado na revisão bibliográfica de artigos científicos publicados na MEDLINE, procuramos rever a regulação da produção da EPO e respetivas funções, bem como abordar o tratamento da anemia da doença renal crónica, com especial enfoque nas novas terapêutica

Anderson-Fabry disease: Ten-year outcome of enzyme replacement therapy in a renal transplant patient

Anderson‑Fabry disease (AFd) is a rare disorder characterised by the deficiency or absence of lysosomal enzymatic alpha‑galactosidase A activity (α‑Gal A) that leads to progressive and systemic accumulation of glycosphingolipids. The clinical manifestations are variable but kidney disease usually manifests before the fourth decade of life and chronic renal failure rapidly progresses to end‑stage renal disease (ESRD), requiring dialysis and kidney transplantation (KT). In patients with a definite diagnosis, enzyme replacement therapy (ERT) is recommended as soon as there are early clinical signs of kidney, heart or brain involvement. We present a case of a kidney transplant patient who was diagnosed with AFd nine years after KT, confirming the difficulty that may exist in na early diagnosis of this disease even among high‑risk groups. At this stage, in addition to renal damage, the patient already had advanced disease and established organ injury, including ocular, pulmonary, cerebrovascular and cardiac. He started agalsidase beta (Fabrazyme®) intravenously every two weeks at a dose of 1 mg/kg body weight. During ten years of treatment no major adverse events were reported and our experience indicates that ERT is a safe and effective treatment for extra‑renal Fabry manifestations in KT patientsinfo:eu-repo/semantics/publishedVersio