Probabilistic amplification through photon addition, at the output of an Mach-Zehnder interferometer is discussed for a coherent input state. When a metric of signal to noise ratio is considered, ...nondeterministic, noiseless amplification of a coherent state shows improvement over a standard coherent state, for the general addition of \(m\) photons. The efficiency of realizable implementation of photon addition is also considered and shows how the collected statistics of a post selected state, depend on this efficiency. We also consider the effects of photon loss and inefficient detectors.
Previous studies have shown that Fc epsilon RII-bearing platelets from patients with allergic disorders could be stimulated either by anti-human IgE antibodies or the relevant allergens to generate ...cytotoxic mediators. In this report, the reactivity of platelets from Dermatophagoides pteronyssinus (D. pt)-sensitive patients to three Der p I-derived synthetic peptides (52-71, 117-133 and 188-199) was investigated. The platelet stimulation observed in D. pt-sensitive patients was demonstrated to be allergen-specific and to be mediated by IgE. These Der p I-derived peptides failed to stimulate platelets from healthy donors or platelets from non-D. pt-allergic patients. D. pt-sensitive patients responded more frequently to the peptides 52-71 and 117-133 than to the peptide 188-199. Thus, in this model, synthetic peptides selected for their assumed accessibility on the native antigen could be associated to an IgE-dependent biological activity.
El presente artículo pretende analizar el papel jugado por los emprendimientos comerciales de tipo shopping centers en la planeación urbana así como el modus operandi de la intervención sobre el ...espacio de actores sociales (desarrolladores, habitantes, municipio) involucrados en la producción de las “nuevas” periferias de clases medias altas. Trataremos en particular del caso de plazas comerciales cuyas formas arquitectónicas se jactan de “buena” calidad urbana y respeto al medio ambiente. Lejos de ser una ausencia de reglamentos o un retiro del gobierno de la planeación y gestión de las periferias, el laissez-faire es una modalidad particular de intervención de los poderes públicos en ciertos espacios, cuando éstos buscan imponerse y mostrarse en otros, en particular en el centro metropolitano. El comercio establecido de buen nivel socioeconómico es un buen instrumento de visibilización de los actores sociales en diferentes territorios. El artículo se apoya en el estudio de caso de un shopping center en Barra da Tijuca en Río de Janeiro donde los juegos de actores a nivel local reflejan la actuación a otras escalas (subregional y urbana) ya que se insertan dentro de un corpus normativo, reglamentario y discursivo municipal.
We propose and implement a quantum procedure for enhancing the sensitivity with which one can determine the phase shift experienced by a weak light beam possessing thermal statistics in passing ...through an interferometer. Our procedure entails subtracting exactly one (which can be generalized to m) photons from the light field exiting an interferometer containing a phase-shifting element in one of its arms. As a consequence of the process of photon subtraction, and somewhat surprisingly, the mean photon number and signal-to-noise ratio of the resulting light field are thereby increased, leading to enhanced interferometry. This method can be used to increase measurement sensitivity in a variety of practical applications, including that of forming the image of an object illuminated only by weak thermal light.
Humoral and cellular responses to Schistosoma bovis antigens have been evaluated over a period of 11 weeks in mice exposed to S. bovis cercariae and data analysed in the context of the parasitic ...parameters (worm and egg loads) recorded at days 30, 60 and 80 of the ongoing infection. Results revealed a decrease of worm burden, particularly marked for female worms, between day 60 and day 80 of infection suggesting a higher susceptibility of female schistosomes to attrition mechanisms. The B‐cell response, studied by measuring the production of different isotypes, was directed against different stage specific antigens, with a predominance of IgG1 antibodies associated with a significant increase of IgA and IgE antibodies after egg deposition. The T‐cell response, assessed after in vitro stimulation of splenocytes, showed a predominant production of Th‐2 cytokines (IL‐4, IL‐5 and IL‐10) occurring after egg laying. Interestingly in contrast to S. mansoni infection the Th‐2 polarization did not seem to be exclusively triggered by egg‐associated antigens since significant amounts of IL‐10 were produced after stimulation with adult worm antigen preparation (SWAP) before the beginning of egg deposition.
Crohn's disease (CD) lesions are characterized by a marked neutrophilic infiltrate associated with enhanced mucosal IL-8, contrasting with low serum IL-8 levels. The aim of this study was to ...investigate the effects of circulating GROalpha and IL-8 on neutrophil priming and migration. The expression of surface molecules involved in rolling (CD62L, CD15) and firm adhesion (Mac-1 and LFA-1) to endothelial cells was assessed by flow cytometry, while the chemotactic response of PMN to IL-8 and to fMLP was investigated in a Boyden chamber assay. In addition, IL-8 and GROalpha levels were determined by ELISA in plasma samples and in culture supernatants of purified polymorphonuclear neutrophils (PMN) and peripheral blood mononuclear cells (PBMC) from patients with CD and healthy blood donors. This study revealed an upregulation of CD11b (Mac-1) membrane expression on circulating PMN from patients with CD, as assessed by the mean fluorescence intensity which reflects antigen density. Furthermore, an enhanced chemotactic response towards both fMLP and IL-8 of PMN from CD patients was observed. Despite often undetectable levels of circulating IL-8, all plasma samples were positive for GROalpha, with a significant increase in CD patients when compared to donors. In vitro, equivalent concentrations of GROalpha were able to increase the IL-8 driven chemotaxis of PMN. In conclusion, blood PMN from patients with CD showed an enhanced capacity to be recruited into inflammed intestinal mucosa, which could be due to an increased expression of CD11b (Mac-1) as well as an increased chemotactic response toward fMLP or IL-8. This priming effect of PMN in CD may partly occur through elevated circulating GROalpha levels.
Large-scale isolation of islets of Langerhans is one of the major obstacles in islet transplantation. Until now, isolation methods relied on enzymatic digestion, the duration of which relies on a ...decision dictated by the operator's experience. This approach has always hindered development of an automated method. The aim of this study was to develop a one-step method based on complete digestion of the pancreas. The original aspect of the technique (derived from the Ricordi method) is use of the University of Wisconsin (UW) solution in the digestion medium and a continuous flow collagenase processing circuit with local cooling and rewarming to allow tissue digestion to proceed at 37 degrees C while settling of the cell suspension takes place at 4 degrees C. A stopcock system permits the alternate use of two settling chambers so that while one is in the circuit, the other can be removed for centrifugation, resuspension of the crude islet preparation in collagenase in free UW solution, and further purification in a density gradient system. Ten experiments were performed, and 545,750 +/- 48,670 purified pig islets were obtained per totally digested pancreas. Histological studies showed cell integrity. Insulin secretion in response to double glucose stimulation under perfusion conditions demonstrated the functional viability of the isolated islets. In conclusion, this one-step method makes it possible to obtain a high number of viable islets of Langerhans in the absence of any decision by an operator, and it should therefore provide basis for an automated method.
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