157 research outputs found
Euros and Zeros: The Common Currency Effect on Trade in New Goods
This paper tests whether trade in new goods is partially responsible for the pro-trade effects of the euro and provides a measure of the size of the effect. It works with a very large data set (about 16 million observations) covering twenty countries at the most disaggregated level of trade data that is publicly available. Using predictions from a heterogeneous-firms trade model in a multi-country environment to structure our empirical model, we find that the euro had a positive impact on trade overall. Our findings provide supportive but not conclusive evidence for the new-goods hypothesis. We also determined the pro-trade effect of euro-usage on non-Euroland nations trading with euro-users. We confirmed the absence of trade diversion for non-Eurozone EU members with sizeable overall increase comparable to that of members.
Visualization of a Small Jet Synthetic Using a Particle Image Velocimetry and Background-Oriented Schlieren Techniques
This work reports the results of experimental investigations carried out on a submerged synthetic jet obtained through the use of a headset speaker piloted with an appropriate sinusoidal signal at a frequency of 380 Hz. The study begins with the construction of a device that, exploiting the well-known transport properties of impacting jets, was able to improve local ventilation and the removal of excess moisture, due to the natural transpiration of human skin in people forced to assume the same position for prolonged periods such as professional drivers; bedridden patients; etc⊠Subjects are substantially forced to have parts of their own body in contact with fabrics and coverings that hinder the normal conditions of skin transpiration. The experimental activity was first based on the study of the structure of the synthetic jets, then moving on to the creation of a sponge mat equipped with 80 individual jets. On this sponge mat, semi-empirical tests were carried out in order to remove moisture from a fabric soaked in distilled water. The experimental investigations were first carried out using the PIV technique, and, subsequently, the synthetic jet was visualized using the Background-Oriented Schlieren (BOS) technique which allowed to test the presence of the jets, installed directly on the mattress, in a relatively simple and fast way, requiring a very simplified set-up
Flow Field Measurements in a Large Controlled Ventilated Room
A large-scale test room, which represents a Test
Control Room facilities in scale 1:1, has been recently
developed in order to evaluate the internal flow filed induced
by the ventilation system. Due to its crucial relevance in
numerous technical applications, rooms ventilation efficiency
has been subject of several scientific investigations considering
also the restricted requirements that such devices should
satisfy in terms of microbiology, particulate concentration and
pathogen diffusion (Covid-19). Such a large-scale test room
with an internal dimension of 6x6x3 m (corresponding to an
internal volume of 108 m3) has been equipped with four inlets
and twelve exhaust terminal grids, parts of the ventilation
system entirely customary designed. In order to assess effects
of different air flow rates, induced by the ventilation system,
on the internal flow distribution, a relevant number of three
dimensional velocity measurements has been performed,
under isothermal conditions, by using a fiber optic Laser
Doppler Velocimetry. Consistently with the survived literature,
two different inlet flow rates have been considered, in
particular 15 and 30 Air Change per Hour (ACH) respectively
corresponding to 0.45 and 0.90 m3/s. The whole campaign of
measurements has been performed totally in 690 points for a
total of 4140 single velocity components acquired
Perception of room modes in critical listening spaces
Room modes are a recognised problem in small critical listening rooms and are known to cause colouration of sound reproduced within them. Investigations on the causes and solutions for this problem have been carried out for some time. Interest in the topic has extended to loudspeaker manufacturers who have mainly concentrated in developing methods for controlling the loudspeaker-room interaction in order to ameliorate low frequency reproduction. Compared to objective work on passive and active control methods, the study of the subjective perception of room resonances has been somewhat neglected. Available publications mostly concern the effects of single resonances, which are perhaps not fully representative of conditions as experienced in real rooms. A study into the subjective perception of room modes is presented. The experimental methodology employs psychoacoustic techniques to study the perception of factors such as modal distribution, and effects of resonances on single tones. Results show that the subjective perception of room modes is strongly affected by temporal issues, and that changes exerted merely on magnitude frequency response are detectable but not likely to remove the effects of resonances for all listeners. Furthermore, it is shown that a reduction of the modal Q-factor, associated with a reduction of decay rates, has a significant effect in decreasing the detection of resonances. Q-factor difference limen were evaluated for three reference decay characteristics corresponding to reference Q-factors of 30, 10 and 1. The limen were 6±2.8, 10±4.1 and 16±5.4 respectively, meaning that detection of changes to modal decay decreases with decreasing decay time. These results may be used to define more perceptually relevant design guidelines for critical listening environments, and indicate target criteria for control techniques used in room correction. The outcomes of this investigation will have repercussions on the design of better rooms for critical listening.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Semiconductor-based Geometrical Quantum Gates
We propose an implementation scheme for holonomic, i.e., geometrical, quantum
information processing based on semiconductor nanostructures. Our quantum
hardware consists of coupled semiconductor macroatoms addressed/controlled by
ultrafast multicolor laser-pulse sequences. More specifically, logical qubits
are encoded in excitonic states with different spin polarizations and
manipulated by adiabatic time-control of the laser amplitudes . The two-qubit
gate is realized in a geometric fashion by exploiting dipole-dipole coupling
between excitons in neighboring quantum dots.Comment: 4 Pages LaTeX, 3 Figures included. To appear in PRB (Rapid Comm.
Tofacitinib May Inhibit Myofibroblast Differentiation from Rheumatoid-Fibroblast-like Synoviocytes Induced by TGF-ÎČ and IL-6
During rheumatoid arthritis (RA), the pathogenic role of resident cells within the synovial membrane is suggested, especially for a population frequently referred to as fibroblast-like synoviocytes (FLSs). In this study, we assess the markers of myofibroblast differentiation of RA-FLSs by ex vivo observations and in vitro evaluations following the stimulation with both TGF-ÎČ and IL-6. Furthermore, we investigated the possible inhibiting role of tofacitinib, a JAK inhibitor, in this context. Myofibroblast differentiation markers were evaluated on RA synovial tissues by immune-fluorescence or immune-histochemistry. RA-FLSs, stimulated with transforming growth factor (TGF-ÎČ) and interleukin-6 (IL-6) with/without tofacitinib, were assessed for myofibroblast differentiation markers expression by qRT-PCR and Western blot. The same markers were evaluated following JAK-1 silencing by siRNA assay. The presence of myofibroblast differentiation markers in RA synovial tissue was significantly higher than healthy controls. Ex vivo, α-SMA was increased, whereas E-Cadherin decreased. In vitro, TGF-ÎČ and IL-6 stimulation of RA-FLSs promoted a significant increased mRNA expression of collagen I and α-SMA, whereas E-Cadherin mRNA expression was decreased. In the same conditions, the stimulation with tofacitinib significantly reduced the mRNA expression of collagen I and α-SMA, even if the Western blot did not confirm this finding. JAK-1 gene silencing did not fully prevent the effects of stimulation with TGF-ÎČ and IL-6 on these features. TGF-ÎČ and IL-6 stimulation may play a role in mediating myofibroblast differentiation from RA-FLSs, promoting collagen I and α-SMA while decreasing E-Cadherin. Following the same stimulation, tofacitinib reduced the increases of both collagen I and α-SMA on RA-FLSs, although further studies are needed to fully evaluate this issue and confirm our results
FRA-1 protein overexpression is a feature of hyperplastic and neoplastic breast disorders
BACKGROUND: Fos-related antigen 1 (FRA-1) is an immediate early gene encoding a member of AP-1 family of transcription factors involved in cell proliferation, differentiation, apoptosis, and other biological processes. fra-1 gene overexpression has an important role in the process of cellular transformation, and our previous studies suggest FRA-1 protein detection as a useful tool for the diagnosis of thyroid neoplasias. Here we investigate the expression of the FRA-1 protein in benign and malignant breast tissues by immunohistochemistry, Western blot, RT-PCR and qPCR analysis, to evaluate its possible help in the diagnosis and prognosis of breast neoplastic diseases. METHODS: We investigate the expression of the FRA-1 protein in 70 breast carcinomas and 30 benign breast diseases by immunohistochemistry, Western blot, RT-PCR and qPCR analysis. RESULTS: FRA-1 protein was present in all of the carcinoma samples with an intense staining in the nucleus. Positive staining was also found in most of fibroadenomas, but in this case the staining was present both in the nucleus and cytoplasm, and the number of positive cells was lower than in carcinomas. Similar results were obtained from the analysis of breast hyperplasias, with no differences in FRA-1 expression level between typical and atypical breast lesions; however the FRA-1 protein localization is mainly nuclear in the atypical hyperplasias. In situ breast carcinomas showed a pattern of FRA-1 protein expression very similar to that observed in atypical hyperplasias. Conversely, no FRA-1 protein was detectable in 6 normal breast tissue samples used as controls. RT-PCR and qPCR analysis confirmed these results. Similar results were obtained analysing FRA-1 expression in fine needle aspiration biopsy (FNAB) samples. CONCLUSION: The data shown here suggest that FRA-1 expression, including its intracellular localization, may be considered a useful marker for hyperplastic and neoplastic proliferative breast disorders
Redshifts of Emission-Line Objects in the Hubble Ultra Deep Field
We present redshifts for 115 emission-line objects in the Hubble Ultra Deep Field identified through the Grism ACS Program for Extragalactic Science (GRAPES) project using the slitless grism spectroscopy mode of the Advanced Camera for Surveys on the Hubble Space Telescope (HST). The sample was selected by an emission-line search on all extracted one-dimensional GRAPES spectra. We identify the emission lines using line wavelength ratios where multiple lines are detected in the grism wavelength range (5800 Ă
âČ Î» âČ 9600 Ă
), and using photometric redshift information where multiple lines are unavailable. We then derive redshifts using the identified lines. Our redshifts are accurate to ÎŽz â 0.009, based on both statistical uncertainty estimates and comparison with published ground-based spectra. Over 40% of our sample is fainter than typical magnitude limits for ground-based spectroscopy (with i_(AB) > 25 mag). Such emission lines would likely remain undiscovered without our deep survey. The emission-line objects fall into three categories: (1) most are low- to moderate-redshift galaxies (0 †z †2), including many actively star-forming galaxies with strong H II regions; (2) nine are high-redshift (4 †z †7) Lyα emitters; and (3) at least three are candidate active galactic nuclei
A Redshift z=5.4 Lyman alpha Emitting Galaxy with Linear Morphology in the GRAPES/UDF Field
We have discovered an extended Lyman alpha plume associated with a compact
source at redshift 5.4 in slitless spectroscopic data from the Grism ACS
Program for Extragalactic Science (GRAPES) project. The spatial extent of the
emission is about 6 x 1.5 kpc (1 x 0.25 arcsec). Combining our grism data and
the broadband images from the Hubble UltraDeep Field (UDF) images, we find a
Lyman alpha line flux of 2e-17 erg/cm2/s and surface brightness 7e-17
erg/cm2/s/arcsec2. The UDF images show diffuse continuum emission associated
with the Lyman alpha plume (hereafter UDF 5225), with three embedded knots. The
morphology of UDF 5225 is highly suggestive of a galaxy in assembly. It is
moreover possible that the prominent Lyman alpha emission from this object is
due to an active nucleus, and that we are seeing the simultaneous growth
through accretion of a galaxy and its central black hole. Followup observations
at higher spectral resolution could test this hypothesis.Comment: 14 pages, accepted for publication in the Astrophysical Journa
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