39 research outputs found
When do stars in 47 Tucanae lose their mass?
By examining the diffusion of young white dwarfs through the core of the globular cluster 47 Tucanae, we estimate the time when the progenitor star lost the bulk of its mass to become a white dwarf. According to stellar evolution models of the white-dwarf progenitors in 47 Tucanae, we find this epoch to coincide approximately with the star ascending the asymptotic giant branch (AGB) (3.0 +/- 8.1 Myr before the tip of the AGB) and more than ninety million years after the helium flash (with 90% confidence). From the diffusion of the young white dwarfs we can exclude the hypothesis that the bulk of the mass loss occurs on the red-giant branch (RGB) at the 4 sigma level. Furthermore, we find that the radial distribution of horizontal branch stars is consistent with that of the red-giant stars and upper-main-sequence stars and inconsistent with the loss of more than 0.2 solar masses on the RGB at the 6 sigma level
In-vivo two-photon imaging of the honey bee antennal lobe
Due to the honey bee's importance as a simple neural model, there is a great
need for new functional imaging modalities. Herein we report on the use of
two-photon microscopy for in-vivo functional and morphological imaging of the
honey bee's olfactory system focusing on its primary centers, the antennal
lobes (ALs). Our imaging platform allows for simultaneously obtaining both
morphological measurements of the AL and in-vivo calcium recording of neural
activities. By applying external odor stimuli to the bee's antennas, we were
able to record the characteristic odor response maps. Compared to previous
works where conventional fluorescence microscopy is used, our approach offers
all the typical advantages of multi-photon imaging, providing substantial
enhancement in both spatial and temporal resolutions while minimizing
photo-damages and autofluorescence contribution with a four-fold improvement in
the functional signal. Moreover, the multi-photon associated extended
penetration depth allows for functional imaging within profound glomeruli.Comment: 3 pages, 3 figure
Software design and code generation for the engineering graphical user interface of the ASTRI SST-2M prototype for the Cherenkov Telescope Array
ASTRI is an on-going project developed in the framework of the Cherenkov Telescope Array (CTA). An end- to-end prototype of a dual-mirror small-size telescope (SST-2M) has been installed at the INAF observing station on Mt. Etna, Italy. The next step is the development of the ASTRI mini-array composed of nine ASTRI SST-2M telescopes proposed to be installed at the CTA southern site. The ASTRI mini-array is a collaborative and international effort carried on by Italy, Brazil and South-Africa and led by the Italian National Institute of Astrophysics, INAF. To control the ASTRI telescopes, a specific ASTRI Mini-Array Software System (MASS) was designed using a scalable and distributed architecture to monitor all the hardware devices for the telescopes. Using code generation we built automatically from the ASTRI Interface Control Documents a set of communication libraries and extensive Graphical User Interfaces that provide full access to the capabilities offered by the telescope hardware subsystems for testing and maintenance. Leveraging these generated libraries and components we then implemented a human designed, integrated, Engineering GUI for MASS to perform the verification of the whole prototype and test shared services such as the alarms, configurations, control systems, and scientific on-line outcomes. In our experience the use of code generation dramatically reduced the amount of effort in development, integration and testing of the more basic software components and resulted in a fast software release life cycle. This approach could be valuable for the whole CTA project, characterized by a large diversity of hardware components
Case report: PIK3CA somatic mutation leading to Klippel Trenaunay Syndrome and multiple tumors
We report a case of Klippel Trenaunay Syndrome that was monitored both clinically and molecularly over a period of 9Â years. A somatic mosaic mutation of PIK3CA (p(E545G)) was identified using both cfDNA NGS liquid biopsy and tissue biopsy. At the age of 56, due to intervening clonal mutations in PIK3CA background, she developed a squamous cell carcinoma in the right affected leg which was treated surgically. Nine years later, lung bilateral adenocarcinoma arose on PIK3CA mutated tissues supported by different clonal mutations. One year later, the patient died from metastases led by a new FGFR3 clone unresponsive to standard-of-care, immunotherapy-based. Our results highlight the presence of a molecular hallmark underlying neoplastic transformation that occurs upon an angiodysplastic process and support the view that PIK3CA mutated tissues must be treated as precancerous lesions. Importantly, they remark the effectiveness of combining cfDNA NGS liquid and tissue biopsies to monitor disease evolution as well as to identify aggressive clones targetable by tailored therapy, which is more efficient than conventional protocols
The ASTRI SST-2M prototype for the Cherenkov Telescope Array: status after the commissioning phase of the telescope
ASTRI SST-2M is an imaging atmospheric Cherenkov telescope developed by the Italian National Institute of Astrophysics (INAF) in the framework of the Cherenkov Telescope Array (CTA) project as an end-to-end prototype for the Small Size array. Large-, medium-, and small-sized telescopes will compose the CTA observatory that represents the next generation of imaging atmospheric Cherenkov telescopes and will explore the very high-energy domain from a few tens of GeV up to few hundreds of TeV. The ASTRI SST-2M telescope has been installed at the INAF-Catania observing station at Serra La Nave, on Mt. Etna (Sicily, Italy) in September 2014. In these 3 years of open-air operations the telescope has been commissioned and its opto-mechanical performance is now well understood. The apparatus was made ready to host its main scientific instrument, the camera with Silicon-Photomultiplier based detectors. This contribution is a status report on the complete ASTRI SST-2M telescope assembly including the electro-mechanical structure and the optical system
The ASTRI SST-2M prototype for the Cherenkov Telescope Array: opto-mechanical performance
ASTRI SST-2M is an end-to-end telescope prototype developed by the Italian National Institute of Astrophysics (INAF) in the framework of the Cherenkov Telescope Array (CTA). The CTA observatory, with a combination of large-, medium-, and small-sized telescopes (LST, MST and SST, respectively), will represent the next generation of imaging atmospheric Cherenkov telescopes. It will explore the very high-energy domain from a few tens of GeV up to few hundreds of TeV. The ASTRI SST-2M telescope structure and mirrors have been installed at the INAF observing station at Serra La Nave, on Mt. Etna (Sicily, Italy) in September 2014. Its performance verification phase began in autumn 2015. Part of the scheduled activities foresees the study and characterization of the optical and opto-mechanical performance of the telescope prototype. In this contribution we report the results achieved in terms of kinematic model analysis, mirrors reflectivity evolution, telescopes positioning, flexures and pointing model and the thermal behavior
Mount control system of the ASTRI SST-2M prototype for the Cherenkov Telescope Array
The ASTRI SST-2M telescope is an end-to-end prototype proposed for the Small Size class of Telescopes (SST) of the future Cherenkov Telescope Array (CTA). The prototype is installed in Italy at the INAF observing station located at Serra La Nave on Mount Etna (Sicily) and it was inaugurated in September 2014. This paper presents the software and hardware architecture and development of the system dedicated to the control of the mount, health, safety and monitoring systems of the ASTRI SST-2M telescope prototype. The mount control system installed on the ASTRI SST-2M telescope prototype makes use of standard and widely deployed industrial hardware and software. State of the art of the control and automation industries was selected in order to fulfill the mount related functional and safety requirements with assembly compactness, high reliability, and reduced maintenance. The software package was implemented with the Beckhoff TwinCAT version 3 environment for the software Programmable Logical Controller (PLC), while the control electronics have been chosen in order to maximize the homogeneity and the real time performance of the system. The integration with the high level controller (Telescope Control System) has been carried out by choosing the open platform communications Unified Architecture (UA) protocol, supporting rich data model while offering compatibility with the PLC platform. In this contribution we show how the ASTRI approach for the design and implementation of the mount control system has made the ASTRI SST-2M prototype a standalone intelligent machine, able to fulfill requirements and easy to be integrated in an array configuration such as the future ASTRI mini-array proposed to be installed at the southern site of the Cherenkov Telescope Array (CTA)