CORRUGATED FEED-HORN ARRAYS FOR FUTURE CMB POLARIZATION EXPERIMENTS.

This work presents the design realization and performance of a 7-element prototype array of corrugated feedhorns in W-band. The module is fabricated using a so-called \u201cplatelet\u201d technique by milling Aluminum plates. This technique is suitable for low-cost and scalable high performance applications. Room temperature Return Loss measurements show a low (<-30 dB) reflection over a 20% bandwidth with a maximum matching of -40 dB at 105 GHz for all seven antennas. Beam pattern measurements indicate good repeatability and a low (-30 dB) sidelobe levels. This work is particularly relevant for future Cosmic Microwave Background polarisation measurements, which require large microwave cryogenic detector arrays coupled to high performance corrugated feed horns

The Large-Scale Polarization Explorer (LSPE)

The LSPE is a balloon-borne mission aimed at measuring the polarization of the Cosmic Microwave Background (CMB) at large angular scales, and in particular to constrain the curl component of CMB polarization (B-modes) produced by tensor perturbations generated during cosmic inflation, in the very early universe. Its primary target is to improve the limit on the ratio of tensor to scalar perturbations amplitudes down to r = 0.03, at 99.7% confidence. A second target is to produce wide maps of foreground polarization generated in our Galaxy by synchrotron emission and interstellar dust emission. These will be important to map Galactic magnetic fields and to study the properties of ionized gas and of diffuse interstellar dust in our Galaxy. The mission is optimized for large angular scales, with coarse angular resolution (around 1.5 degrees FWHM), and wide sky coverage (25% of the sky). The payload will fly in a circumpolar long duration balloon mission during the polar night. Using the Earth as a giant solar shield, the instrument will spin in azimuth, observing a large fraction of the northern sky. The payload will host two instruments. An array of coherent polarimeters using cryogenic HEMT amplifiers will survey the sky at 43 and 90 GHz. An array of bolometric polarimeters, using large throughput multi-mode bolometers and rotating Half Wave Plates (HWP), will survey the same sky region in three bands at 95, 145 and 245 GHz. The wide frequency coverage will allow optimal control of the polarized foregrounds, with comparable angular resolution at all frequencies.Comment: In press. Copyright 2012 Society of Photo-Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibite

A coherent polarimeter array for the Large Scale Polarization Explorer balloon experiment

We discuss the design and expected performance of STRIP (STRatospheric Italian Polarimeter), an array of coherent receivers designed to fly on board the LSPE (Large Scale Polarization Explorer) balloon experiment. The STRIP focal plane array comprises 49 elements in Q band and 7 elements in W-band using cryogenic HEMT low noise amplifiers and high performance waveguide components. In operation, the array will be cooled to 20 K and placed in the focal plane of a $\sim 0.6$ meter telescope providing an angular resolution of $\sim1.5$ degrees. The LSPE experiment aims at large scale, high sensitivity measurements of CMB polarization, with multi-frequency deep measurements to optimize component separation. The STRIP Q-band channel is crucial to accurately measure and remove the synchrotron polarized component, while the W-band channel, together with a bolometric channel at the same frequency, provides a crucial cross-check for systematic effects.Comment: In press on the Proceedings of the SPIE Conference Astronomical Telescopes + instrumentation 2012, Amsterdam, paper 8446-27

QUBIC: A Fizeau Interferometer Targeting Primordial B-Modes

Q and U Bolometric Interferometer for Cosmology (QUBIC) is a Fizeau interferometer sensitive to linear polarisation, to be deployed at the Antarctic station of Dome C. This experiment in its final configuration will be operated at 97, 150 and 220 GHz and is intended to target CMB primordial B-modes in a multipole window 20<ℓ<150. A sensitivity of r=0.05 (95 % CL) can be reached by the first module alone, after 2 years of operation. Here we review in particular its working principles, and we show how the QUBIC interferometric configuration can be considered equivalent to a pupil-plane filtered imaging system. In this context, we show how our instrument can be self-calibrated. Finally, we conclude by showing an overview of the first dual-band module (150/220 GHz), which will serve also as a demonstrator for the subsequent units, and review the technological choices we made for each subsystem, with particular emphasis on the detection system

Time-resolved dual transcriptomics reveal early induced Nicotiana benthamiana root genes and conserved infection-promoting Phytophthora palmivora effectors

BACKGROUND: Plant-pathogenic oomycetes are responsible for economically important losses in crops worldwide. Phytophthora palmivora, a tropical relative of the potato late blight pathogen, causes rotting diseases in many tropical crops including papaya, cocoa, oil palm, black pepper, rubber, coconut, durian, mango, cassava and citrus. Transcriptomics have helped to identify repertoires of host-translocated microbial effector proteins which counteract defenses and reprogram the host in support of infection. As such, these studies have helped in understanding how pathogens cause diseases. Despite the importance of P. palmivora diseases, genetic resources to allow for disease resistance breeding and identification of microbial effectors are scarce. RESULTS: We employed the model plant Nicotiana benthamiana to study the P. palmivora root infections at the cellular and molecular levels. Time-resolved dual transcriptomics revealed different pathogen and host transcriptome dynamics. De novo assembly of P. palmivora transcriptome and semi-automated prediction and annotation of the secretome enabled robust identification of conserved infection-promoting effectors. We show that one of them, REX3, suppresses plant secretion processes. In a survey for early transcriptionally activated plant genes we identified a N. benthamiana gene specifically induced at infected root tips that encodes a peptide with danger-associated molecular features. CONCLUSIONS: These results constitute a major advance in our understanding of P. palmivora diseases and establish extensive resources for P. palmivora pathogenomics, effector-aided resistance breeding and the generation of induced resistance to Phytophthora root infections. Furthermore, our approach to find infection-relevant secreted genes is transferable to other pathogen-host interactions and not restricted to plants.This work was supported by the Gatsby Charitable Foundation (RG62472), by the Royal Society (RG69135) and by the European Research Council (ERC-2014-STG, H2020, 637537)

Postural Changes after Abdominoplasty in Morbid Obese Patients

Background In the multidisciplinary treatment of obesity, the role of a plastic surgeon is to remove the excess of skin after weight loss to obtain cosmetic, functional, and psychological benefits. Obesity modifies body geometry, increases the mass of different segments, and imposes functional limitations in life activities that may predispose the obese to injury. The authors evaluated the postural conditions of obese patients, before and 12 months after surgery. Methods The study included 15 obese patients of both genders affected by class II obesity. Postural function was evaluated preoperatively and 12 months postoperatively. Patients underwent conventional abdominoplasty surgical procedure. In all patients, plantar pressure distribution and balance (stabilometric test) were evaluated before and 3 months after surgery. Results The static pedobarographic revealed a significant reduction in forefoot peak pressure; total plantar force; rearfoot plantar force percentage; midfoot plantar force percentage; and forefoot, midfoot, and rearfoot plantar contact areas percentage 3 months after surgery; the dynamic's one showed a reduction in the first metatarsal peak pressure and plantar contact. The stabilometric values showed a reduction in the range of center of foot pressure (CP) displacement along y axis, the average displacement of the CP speed from the mean (RMS y velocity), and CP mean peak in the condition of vision. Conclusions Our study demonstrates the beneficial effect of dermolipectomies and the consequential weight loss on postural stability of obese men. Such findings may support the hypothesis that dermolipectomy may improve postural stability with and without vision. The data demonstrate that the benefits are related to the magnitude of the resected tissue

A platelet W-band feed horn-OMT assembly

Future Cosmic Microwave Background polarisation experiments will require large detector arrays to achieve the required sensitivity for precise measurements. New cost- and time-effective techniques are required for mass production of high performance passive components. We present electromagnetic test results on an assembly of feed horn and OMT prototypes, operating in the W-band and fabricated by means of 'platelet' technique. The good level of isolation and return loss (respectively >45 dB, >30 dB on 20% bandwidth) for both polarizations are in agreement with numerical simulations, indicating good matching between components. Radiation patterns are also in agreement with simulations, with cross-polarization level < -30 dB on a 20% bandwidth. These results confirm the good design, manufacturing and assembling of the prototypes

PLATELET RICH FIBRIN MATRIX EFFECTS ON SKELETAL MUSCLE LESIONS: AN EXPERIMENTAL STUDY

Even though muscle injuries are very common, few scientific data on their effective treatment exist. Growth Factors (GFs) may have a role in accelerating muscle repair processes and a currently available strategy for their delivery into the lesion site is the use of autologous platelet-rich plasma (PRP). The present study is focused on the use of Platelet Rich Fibrin Matrix (PRFM), as a source of GFs. Bilateral muscular lesions were created on the longissimus dorsi muscle of Wistar rats. One side of the lesion was filled with a PRFM while the contralateral was left untreated (controls). Animals were sacrificed at 5, 10, 40 and 60 days from surgery. Histological, immunohistochemical and histomorphometric analyses were performed to evaluate muscle regeneration, neovascularization, fibrosis and inflammation. The presence of metaplasic zones, calcifications and heterotopic ossification were also assessed. PRFM treated muscles exhibited an improved muscular regeneration, an increase in neovascularization, and a slight reduction of fibrosis compared with controls. No differences were detected for inflammation. Metaplasia, ossification and heterotopic calcification were not detected. This preliminary morphological experimental study shows that PRFM use can improve muscle regeneration and long-term vascularization. Since autologous blood products are safe, PRFM may be a useful and handily product in clinical treatment of muscle injuries