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COSMO is a ground-based instrument to measure the spectral distortions (SD) of the Cosmic Microwave Background (CMB). In this paper, we present preliminary results of electromagnetic simulations of its reference blackbody calibrator. HFSS simulations provide a calibrator reflection coefficient of R ∼ 10 - 6 , corresponding to an emissivity ϵ = 1 - R = 0.999999 . We also provide a forecast for the instrument performance by using an ILC-based simulation. We show that COSMO can extract the isotropic Comptonization parameter (modeled as | y | = 1.77 · 10 - 6 ) as | y | = ( 1.79 ± 0.19 ) · 10 - 6 , in the presence of the main Galactic foreground (thermal dust) and of CMB anisotropies, and assuming perfect atmospheric emission removal.

With this contribution we show the readout electronics for kinetic inductance detectors (KIDs) that we are developing based on commercial IQ transceivers from National Instruments and using a Virtex 5 class FPGA. It will be the readout electronics of the COSmic Monopole Observer (COSMO) experiment, a ground based cryogenic Martin–Puplett Interferometer searching for the cosmic microwave background spectral distortions. The readout electronics require a sampling rate in the range of tens of kHz, which is both due to a fast rotating mirror modulating the signal and the time constant of the COSMO KIDs. In this contribution we show the capabilities of our readout electronics using Niobium KIDs developed by Paris Observatory for our 5 K cryogenic system. In particular, we demonstrate the capability to detect 23 resonators from frequency sweeps and to readout the state of each resonator with a sampling rate of about 8 kHz. The readout is based on a finite-state machine where the first two states look for the resonances and generate the comb of tones, while the third one performs the acquisition of phase and amplitude of each detector in free running. Our electronics are based on commercial modules, which brings two key advantages: they can be acquired easily and it is relative simple to write and modify the firmware within the LabView environment in order to meet the needs of the experiment.

The forthcoming generation of cosmic microwave background polarization observatories is developing large format detector arrays which will operate at 100 mK. Given the volume of detector wafers that will be required, fast-cooldown 100 mK test cryostats are increasingly needed. A miniature dilution refrigerator (MDR) has been developed for this purpose and is reported. The MDR is precooled by a double-stage 3 He – 4 He Chase Research Cryogenics sorption refrigerator. The test cryostat based on this MDR will enable fast cooldown to 100 mK to support rapid feedback testing of detector wafers fabricated for the Simons Observatory. The MDR has been designed to provide a 100 mK stage to be retrocompatible with existing CRC10 sorption coolers, reducing the base temperature from 250 mK for the new generation of detectors. Other 250 mK cryostats can be retrofitted in the same way. This configuration will meet the cryogenic requirements for single-wafer testing, providing 5–10  μ W of cooling power at 100 mk for over 8 h. The system operates in a closed cycle, thereby avoiding external gas connections and cold o-rings. No moving parts are required, with the system operated entirely by heaters.

We have measured in the W-band, using a custom setup, the absorption and polarization properties in transmission of foam materials (elyfoamⓇ, styrodurⓇ, plastazoteⓇ, and propozoteⓇ) useful for windows of mm-wave photometers and polarimeters. The levels of the induced polarization degree and of the absorption are very small, and difficult to measure accurately. We find induced polarization degrees lower than 0.6 %, and transmissions higher than 97 % for few centimeter thicknesses of our samples. We describe the instrumental setup, the measurements, and the impact of our findings in the design of precision polarimeters for Cosmic Microwave Background measurements. All these materials, with the exception of black plastazoteⓇ, feature transmissions higher than 99 %, and induced polarizations lower than ∼1 % for sample thicknesses around 2–3 cm.

As the forthcoming generation of Cosmic Microwave Background observatories move towards the use of large format detector arrays operating at ~100 mK, the need for test cryostats capable of operating in this temperature regime is becoming more pronounced. This has strongly driven the development of several related systems, including the continuous miniature dilution refrigerator (MDR) reported here. The MDR is comprised of a thermally separated mixing chamber, step heat exchangers, twin stills and twin condensation pumps. The pumps are alternately cooled to ~300 mK by a pair of single-shot 1He sorption coolers (cycled in anti-phase) to circulate 3He in the system. The system is therefore closed-cycle, with the circulation of 3He, both in the MDR and sorption coolers, contained to the cold stage. As a result, the reliability of the system is improved through a mechanically simple design and the absence of external connections, gas handling systems, and cold o-rings.

Thoracic endovascular aortic repair (TEVAR) has emerged as a promising, less invasive alternative to conventional open surgery for the treatment of thoracic aortic pathology. Most surveillance after TEVAR concentrates on the technical aspects of the procedure, including endoleak, device migration and endograft rupture; so far, the knowledge on endograft infectious complications is limited to anecdotal reports. Several etiopathogenetic factors may play a role in thoracic endograft infections (TEIs), including perioperative contamination, hematogenous seeding, and local bacterial translocation. Moreover, fistulization with the esophagus or the bronchial tree is a common mechanism of secondary TEI, and it represents a dramatic event requiring a multidisciplinary management. Risk factors assessment and prevention have a key role in avoiding the development of new TEIs. When a TEI is established, treatment is demanding, and includes several medical therapies associated with various surgical options. Patients are usually severely compromised by sepsis, and in most cases they are considered unfit for surgery for general clinical conditions or local concerns. Thus, results of different therapeutic strategies for TEI are still burdened with very high morbidity and mortality. In this paper, we reviewed the English literature regarding the main strategies proposed for operative management of TEI, we reported and analyzed our personal series of 7 patients treated at our institution for TEI from 1999 to 2009, and we summarized results from the data collected during a recent Italian multicenter national survey, performed to investigate aortoesophageal and aortobronchial fistulae treated with TEVAR or developed following TEVAR.

Lipid microparticles (lipospheres) loaded with butyl methoxydibenzoylmethane (BMDBM), a widely used UV-A sunscreen agent, were prepared by melt technique and evaluated for skin permeation both in vivo, by tape stripping method, and in vitro, by a flow-through diffusion chamber. Following in vivo human skin application of an O/W emulsion containing 2% of BMDBM loaded in lipospheres, 15% of the applied sunscreen accumulated in the uppermost layers of the stratum corneum without remarkably modifying the skin permeation of the unencapsulated sunscreen. These results were found to be predicted by an in vitro methodology involving the diffusion of BMDBM through a lipophilized synthetic membrane into a hydrophilic receptor phase, simulating the viable epidermis better than an ethanolic receptor phase.

The aim of this Italian prospective registry was to evaluate the applicability and efficacy of the Mo.Ma Device (Invatec, Roncadelle, Italy) for the prevention of cerebral embolization during carotid artery stenting (CAS) in a real world population. In 4 Italian centers, 416 patients (300 men; mean age 71.6+/-9 years) between October 2001 and March 2005 were enrolled in a prospective registry. Two-hundred and sixty-four symptomatic (63.46%) with >50% diameter stenosis and 152 (36.54%) asymptomatic patients with >70% diameter stenosis were included. The Mo.Ma Proximal Flow Blockage Embolic Protection System was used to perform protected CAS, achieving cerebral protection by endovascular clamping of the common carotid artery (CCA) and of the external carotid artery (ECA). Technical success, defined as the ability to establish protection with the Mo.Ma device and to deploy the stent, was achieved in 412 cases (99.03%). The mean duration of flow blockage was 4.91+/-1.1 min. Transient intolerances to flow blockage were observed in 24 patients (5.76%), but in all cases the procedure was successfully completed. No peri-procedural strokes and deaths were observed. Complications during hospitalization included 16 minor strokes (3.84%), 3 transient ischemic attacks (0.72%), 2 deaths (0.48%) and 1 major stroke (0.24%). This resulted in a cumulative rate at discharge of 4.56% all strokes and deaths, and of 0.72% major strokes and deaths. All the patients underwent thirty-day follow-up. At thirty-day follow-up, there were no deaths and no minor and major strokes, confirming the overall cumulative 4.56% incidence of all strokes and deaths rate, and of 0.72% rate of major strokes and deaths at follow up. In 245 cases (58.89%) there was macroscopic evidence of debris after filtration of the aspirated blood. This Italian multicenter registry confirms and further supports the efficacy and applicability of the endovascular clamping concept with proximal flow blockage in a broad patient series. Results match favorably with current available studies on carotid stenting with cerebral protection.

The aim of this paper was to reduce the incidence of clamping intolerance, asystolia, immediate mortality and neurological complications associated with carotid artery stenting (CAS) using the Mo.Ma system (Invatec, Roncadelle Brescia, Italy) embolic protection device (EPD). CAS was perfomed using the Mo.Ma system in 312 patients between January 2002-October 2009. From October 2008 variations to the standard technique were introduced. A total of 214 patients were treated with the standard technique, and 88 with the new technique. Improvements include the engagement of the guidewire's floppy tip through the lesion whilst the cerebral blood flow is maintained, a slow release post-dilation (1 atm/2 s), a quicker manual aspiration procedure following post-dilation, a redirection of blood flow into the external carotid artery (ECA) with the post-dilation balloon inflated in the internal carotid artery (ICA), and a further manual aspiration and the subsequent release of the Mo.Ma system. This study reports reduced incidence of clamping intolerance (7.9% vs. 4.5%), asystolia (0 vs. 1.9%), immediate mortality (0 vs. 0.9%) and neurological complications (1.1% vs. 3.7%). The only neurological complication associated with the new technique was a transient ischemic attack (TIA). The new variations of the standard Mo.Ma technique seem rational in the improvement of the safety and efficacy of CAS using an EPD, in reducing the incidence of clamping intolerance and asystolia, immediate mortality and neurological complications. This series indicates a positive trend for this revised technique, but a multicentre registry is required to validate these promising results.