407 research outputs found
Latest data constraint of some parameterized dark energy models
Using various latest cosmological datasets including Type-Ia supernovae,
cosmic microwave background radiation, baryon acoustic oscillations, and
estimations of the Hubble parameter, we test some dark energy models with
parameterized equations of state and try to distinguish or select
observation-preferred models. We obtain the best fitting results of the six
models and calculate their values of the Akaike Information Criteria and Bayes
Information Criterion. And we can distinguish these dark energy models from
each other by using these two information criterions. However, the CDM model remains the best fit model. Furthermore, we perform geometric
diagnostics including statefinder and Om diagnostics to understand the
geometric behaviour of the dark energy models. We find that the six DE models
can be distinguished from each other and from CDM, Chaplygin gas,
quintessence models after the statefinder and Om diagnostics were performed.
Finally, we consider the growth factor of the dark energy models with
comparison to CDM model. Still, we find the models can be
distinguished from each other and from CDM model through the growth
factor approximation.Comment: 23 pages, 6 figures, to be published in CP
Two-photon interference with two independent pseudo-thermal sources
The nature of two-photon interference is a subject that has aroused renewed
interest in recent years and is still under debate. In this paper we report the
first observation of two-photon interference with independent pseudo-thermal
sources in which sub-wavelength interference is observed. The phenomenon may be
described in terms of the classical statistical distribution of the two sources
and their optical transfer functions.Comment: Phys. Rev. A 74, 053807 (2006
Correlated two-photon imaging with true thermal light
We report the first experimental demonstration of two-photon correlated
imaging with true thermal light from a hollow cathode lamp. The coherence time
of the source is much shorter than that of previous experiments using random
scattered light from a laser. A two-pinhole mask was used as object, and the
corresponding thin lens equation was well satisfied. Since thermal light
sources are easier to obtain and measure than entangled light it is conceivable
that they may be used in special imaging applications.Comment: 3 pages, 5 figures, accepted by Optics Letter
Casimir Pistons for Massive Scalar Fields
The Casimir force on two-dimensional pistons for massive scalar fields with
both Dirichlet and hybrid boundary conditions is computed. The physical result
is obtained by making use of generalized -function regularization
technique. The influence of the mass and the position of the piston in the
force is studied graphically. The Casimir force for massive scalar field is
compared to that for massless scalar field.Comment: 6 pages, 7 figures, in press version of Mod. Phys. Lett.
Two-photon interference with true thermal light
Two-photon interference and "ghost" imaging with entangled light have
attracted much attention since the last century because of the novel features
such as non-locality and sub-wavelength effect. Recently, it has been found
that pseudo-thermal light can mimic certain effects of entangled light. We
report here the first observation of two-photon interference with true thermal
light.Comment: 4 pages, 5 figures, PRA72, 043805 (2005
Clinical features and treatment of pediatric patients with drug-induced anaphylaxis: a study based on pharmacovigilance data
We assessed the clinical features and treatment of pediatric patients with drug-induced anaphylaxis in clinical settings. Pediatric drug-induced anaphylaxis cases collected by the Beijing Pharmacovigilance Database from 2004 to 2014 were analyzed. A total of 91 cases were identified. Drug-induced anaphylaxis was primarily caused by antibiotics (53%). Children of 0-5 years were more likely to develop cyanosis symptoms than children of 13-17 years (OR = 5.14, 95%CI [1.74, 15.20], P = 0.002). Children of 13-17 years were more likely to develop hypotension than children of 6-12 years (OR = 11.79, 95%CI [2.28, 60.87], P = 0.002), and to manifest both neurological symptoms (OR = 3.56, 95%CI [1.26, 10.08], P = 0.015) and severe anaphylaxis than children of 0-5 years (OR = 15.46, 95%CI [1.85, 129.33], P = 0.002). Supratherapeutic doses of epinephrine were more likely with intravenous (IV) bolus (92%) in contrast to either intramuscular (IM) (36%, OR = 19.25, 95%CI [1.77, 209.55], P = 0.009) or subcutaneous (SC) injections (36%, OR = 19.80, 95% CI [1.94, 201.63], P = 0.005). Only 62 (68%) patients received epinephrine treatment as the first-line therapy.
CONCLUSION: This study demonstrates that antibiotics were the most common cause of pediatric drug-induced anaphylaxis. Children may present with different anaphylactic signs/symptoms based on age groups. Epinephrine is under-utilized and provider education on the proper management of drug-induced anaphylaxis is warranted. What is Known: • The most common causes of anaphylaxis in children are allergies to foods. Drugs are the second most common cause of pediatric anaphylaxis. • IM epinephrine is the recommended initial treatment of anaphylaxis. What is New: • Drug-induced anaphylaxis in pediatric patients has age-related clinical features. • IV bolus epinephrine was overused and associated with supratherapeutic dosing
Clinical and Prognostic Value of PET/CT Imaging with Combination of 68
Background. To evaluate the clinical and prognostic value of PET/CT with combination of 68Ga-DOTATATE and 18F-FDG in gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs). Method. 83 patients of GEP-NENs who underwent 68Ga-DOTATATE and 18F-FDG PET/CT were enrolled between June 2013 and December 2016. Well-differentiated (WD) NETs are divided into group A (Ki-67 < 10%) and group B (Ki-67 ≥ 10%), and poorly differentiated (PD) NECs are defined as group C. The relationship between PET/CT results and clinicopathological characteristics was retrospectively investigated. Result. For groups A/B/C, the sensitivities of 68Ga-DOTATATE and 18F-FDG were 78.8%/83.3%/37.5% and 52.0%/72.2%/100.0%. A negative correlation between Ki-67 and SUVmax of 68Ga-DOTATATE (R = −0.415; P ≤ 0.001) was observed, while a positive correlation was noted between Ki-67 and SUVmax of 18F-FDG (R = 0.683; P ≤ 0.001). 62.5% (5/8) of patients showed significantly more lesions in the bone if 68Ga-DOTATATE was used, and 22.7% (5/22) of patients showed more lymph node metastases if 18F-FDG was used. Conclusions. The sensitivity of dual tracers was correlated with cell differentiation, and a correlation between Ki-67 and both SUVmax of PET-CTs could be observed. 68Ga-DOTATATE is suggested for WD-NET and 18F-FDG is probably suitable for patients with Ki-67 ≥ 10%
Detection and Analysis of Blood Dexmedetomidine in Drug-Facilitated Cases
Objective To establish a simple and rapid qualitative and quantitative detection method of dexmedetomidine in blood. Methods Blood was separated on the Allure PFP Propyl liquid chromatography column with isocratic elution after it was precipitated by acetonitrile and filtered. Qualitative and quantitative analysis of dexmedetomidine was performed using positive ion scan mode and multi-reaction monitoring mode. Results The limit of detection of dexmedetomidine in blood was 0.2 ng/mL and the limit of quantification was 0.5 ng/mL. The linearity of the method was good in the range of 0.5-1 000 ng/mL, and the correlation coefficient was greater than 0.99. The accuracy of the method was 90.34%-112.67% and the extraction recovery was 50.05%-91.08%, with no significant matrix effect. Conclusion This method is simple, selective and suitable for the qualitative and quantitative analysis of dexmedetomidine in blood, which can provide a reference for drug-facilitated cases involving dexmedetomidine
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