The precise measurement of forces is one way to obtain deep insight into the fundamental interactions present in nature. In the context of neutral antimatter, the gravitational interaction is of high ...interest, potentially revealing new forces that violate the weak equivalence principle. Here we report on a successful extension of a tool from atom optics--the moiré deflectometer--for a measurement of the acceleration of slow antiprotons. The setup consists of two identical transmission gratings and a spatially resolving emulsion detector for antiproton annihilations. Absolute referencing of the observed antimatter pattern with a photon pattern experiencing no deflection allows the direct inference of forces present. The concept is also straightforwardly applicable to antihydrogen measurements as pursued by the AEgIS collaboration. The combination of these very different techniques from high energy and atomic physics opens a very promising route to the direct detection of the gravitational acceleration of neutral antimatter.
We study the highly non-linear system consisting of an array of Transition Edge Sensors polarized by AC voltage sources at different frequencies. We show that the quality factor of the resonant ...circuit must be low to avoid self-oscillations.
Increasing interest in safety evaluation of carbon nanotubes (CNTs) has risen in relation to their wide applications, together with the evidence of their cytotoxic effects. It has been shown that ...chemical functionalization extends the applications of CNTs, conferring them new functions that cannot otherwise be acquired by pristine CNTs, but also impacts on biological response to CNTs, modifying their toxicological profile. We assessed the onset of pulmonary toxic effects caused by pristine MW-CNTs and functionalized MW-NH₂ or MW-COOH, 16 days after intratracheal instillation (1 mg/kg b.w.); major endpoints tested included (i) histopathology of lung (Haematoxylin/Eosin Staining), (ii) apoptotic/proliferating features examined by TUNEL and PCNA immunostaining, and (iii) presence/distribution of (1) Transforming Growth Factor-beta1 (TGFß1), (2) Interleukin-6 (IL-6) and (3) Collagen (Type I) investigated by immunochemical methods, as markers of lung toxicity, inflammation, and fibrosis, respectively. Lung histopathology from exposed animals showed dark, particulate-laden macrophages, reflecting carbon nanomaterial engulfing, both at alveolar and bronchiolar levels, after treatment with all the tested CNTs. Alteration of lung architecture was also observed in several areas showing collapsed thick-walled alveoli and the presence of micro-haemorrhagic foci. TUNEL and PCNA, indicative of apoptosis and cell proliferation respectively, showed a significant increase of immunopositive cells at bronchiolar, alveolar and macrophagic levels, as expression of an improved cellular turnover. Increased immunoreactivity for pulmonary TGFß1 and IL-6 was observed in treated rats, particularly in bronchiolar areas, collapsed alveoli and at stromal level, while evident changes for collagen were not detected. Taken together these findings demonstrated the general pulmonary toxicity coupled with inflammatory response after in vivo exposure to CNTs, without overt signs of fibrosis and granuloma formation, irrespectively of nanotube functionalization.
The AEgIS experiment is an international collaboration with the main goal of performing the first direct measurement of the Earth's gravitational acceleration on antimatter. Critical to the success ...of AEgIS is the production of cold antihydrogen (H¯) atoms. The FACT detector is used to measure the production and temperature of the H¯ atoms and for establishing the formation of a H¯ beam. The operating requirements for this detector are very challenging: it must be able to identify each of the thousand or so annihilations in the 1ms period of pulsed H¯ production, operate at 4K inside a 1T solenoidal field and not produce more than 10W of heat. The FACT detector consists of two concentric cylindrical layers of 400 scintillator fibres with a 1mm diameter and a 0.6mm pitch. The scintillating fibres are coupled to clear fibres which transport the scintillation light to 800 silicon photomultipliers. Each silicon photomultiplier signal is connected to a linear amplifier and a fast discriminator, the outputs of which are sampled continuously by Field Programmable Gate Arrays (FPGAs).
In the course of the developments for the FACT detector we have established the performance of scintillating fibres at 4K by means of a cosmic-ray tracker operating in a liquid helium cryostat. The FACT detector was installed in the AEgIS apparatus in December 2012 and will be used to study the H¯ formation when the low energy antiproton physics programs resume at CERN in the Summer of 2014. This paper presents the design requirements and construction methods of the FACT detector and provides the first results of the detector commissioning.
We investigated the preventive effects of resveratrol analogue 4,4'-dihydroxy-trans-stilbene (DHS) on cancer invasion and metastasis. Two different in vivo approaches of mouse and zebrafish lung ...cancer invasion models were employed in our study. The in vitro results showed that DHS displays potent inhibition on anchorage-dependent or -independent cell growth of LLC cells, leading to impairment of the cell cycle progression with reduction of cell numbers arresting at the G1 phase, an evident accumulation of pre-G1 events correlated with apoptotic behaviour. In addition, DHS induces a marked inhibition of LLC cell migration and matrigel invasion. In a murine lung cancer model, tumour volume, cell proliferation, and tumour angiogenesis were significantly inhibited by DHS. Importantly, liver metastatic lesions were significantly reduced in DHS-treated mice. Similarly, DHS significantly inhibits lung cancer cell dissemination, invasion and metastasis in a zebrafish tumour model. These findings demonstrate that DHS could potentially be developed as a novel therapeutic agent for treatment of cancer and metastasis.
We are currently producing iridium based TESs for a wide variety of applications such as single photon detection of the visible and infrared light, X-ray spectroscopy and low energy nuclear beta and ...electron capture spectroscopy for neutrino mass search experiment. We present a study of the TES performance related to the superconductivity properties of the Ir film as function of the production processes, that depend on substrate type: Si or SiN, and of the operating electrical parameters. Moreover we developed a finite element model of thin superconducting film, by which we obtain qualitative agreement between experimental and simulated data.
We present the design and the performances of LTc SQUIDs with integrated micro pick-up coils to employ as magnetic field sensors in high spatial resolution measurements. The circular pick-up coils, ...having an inner diameter ranging from 5 to 50 mum and a line width of 2 mum, are well separated (1.5 mm) from the SQUID body to minimize magnetic interferences. The micro pick-up coils are connected to the SQUID by both magnetometer and gradiometric configurations. All SQUID types contain an integrated modulation/feedback coil for flux locked loop operations. At T = 4.2 K, the sensors have a measured white magnetic flux noise spectral density as low as 3 muPhi 0 /Hz 1/2 . These measurements were made in a flux locked loop, using a direct coupled amplifier, without the use of additional positive feedback. The low noise is attributed to the high intrinsic responsivity of our sensors. Finally, flux gain measurements (the ratio between the measured magnetic flux and the flux applied to the micro pick-up coil), are reported.
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