2,279 research outputs found
Thermodynamics and Chemistry of the Early Universe
The interplay between chemistry and thermodynamics determines the final
outcome of the process of gravitational collapse and sets the conditions for
the formation of the first cosmological objects, including primordial
supermassive black holes. In this chapter, we will review the main chemical
reactions and the most important heating/cooling processes taking place in a
gas of primordial composition, including the effects of local and cosmological
radiation backgrounds.Comment: Preprint of the Chapter "Thermodynamics and Chemistry of the Early
Universe", to be published in the review volume "Formation of the First Black
Holes", Latif M. and Schleicher D.R.G., eds., World Scientific Publishing
Company, 2018, pp. [see
http://www.worldscientific.com/worldscibooks/10.1142/10652
Immunoscintigraphy for therapy decision making and follow-up of biological therapies
With the availability of new biological therapies there is the need of more accurate diagnostic tools to noninvasively
assess the presence of their targets. In this scenario nuclear medicine offers many radiopharmaceuticals for
SPECT or PET imaging of many pathological conditions. The availability of monoclonal antibodies provides tools to
target specific antigens involved in angiogenesis, cell cycle or modulation of the immune systems. The radiolabelling of
such therapeutic mAbs is a promising method to evaluate the antigenic status of each cancer lesion or inflamed sites
before starting the therapy. It may also allow to perform follow-up of such biological therapies. In the present review we
provide an overview of the most studied radiolabelled antibodies for therapy decision making and follow-up of patients
affected by cancer and other pathological conditions
Evaluation of the possible association of body mass index and four metabolic gene polymorphisms with longevity in an Italian cohort: a role for APOE, eNOS and FTO gene polymorphisms
Background: Longevity is considered the result of interactions between environmental and genetic factors. Aim: To investigate the possible association of body mass index and the frequencies of APOE, ACE, eNOS and FTO gene polymorphisms with longevity. Subjects and methods: In total, 1100 healthy volunteers aged 10–100 were recruited. Subjects were genotyped for APOE, ACE, eNOS and FTO gene polymorphisms. Data about height and weight were also collected. The sample was split into four age groups: 1–24, 25–49, 50–85 and 86–100 years. Results: Significant differences were found in BMI values between age groups. A significant decrease of the APOE4, eNOS 393 and FTO A and allele frequencies was observed in the 86–100 age group compared to the younger groups. For ACE gene, no significant differences were found in the allele frequencies between groups. A similar trend was also observed when the sample was subdivided into two main age groups: 1–85 and 86–100 years. Conclusion: This study provides evidence for a role of APOE, eNOS and FTO gene polymorphisms in longevity. It has been estimated that the number of centenarians worldwide will double each decade until 2100, making population data about gene polymorphisms relevant for further studies about longevity
Ultra-low threshold polariton lasing in photonic crystal cavities
The authors show clear experimental evidence of lasing of exciton polaritons
confined in L3 photonic crystal cavities. The samples are based on an InP
membrane in air containing five InAsP quantum wells. Polariton lasing is
observed with thresholds as low as 120 nW, below the Mott transition, while
conventional photon lasing is observed for a pumping power one to three orders
of magnitude higher.Comment: 4 pages, 3 figure
Stimulated and spontaneous four-wave mixing in silicon-on-insulator coupled photonic wire nano-cavities
We report on four-wave mixing in coupled photonic crystal nano-cavities on a
silicon-on-insulator platform. Three photonic wire cavities are side-coupled to
obtain three modes equally separated in energy. The structure is designed to be
self-filtering, and we show that the pump is rejected by almost two orders of
magnitudes. We study both the stimulated and the spontaneous four-wave mixing
processes: owing to the small modal volume, we find that signal and idler
photons are generated with a hundred-fold increase in efficiency as compared to
silicon micro-ring resonators
- …