Lumped Element Kinetic Inductance Detectors for space applications

Kinetic Inductance Detectors (KID) are now routinely used in ground-based telescopes. Large arrays, deployed in formats up to kilopixels, exhibit state-of-the-art performance at millimeter (e.g. 120-300 GHz, NIKA and NIKA2 on the IRAM 30-meters) and sub-millimeter (e.g. 350-850 GHz AMKID on APEX) wavelengths. In view of future utilizations above the atmosphere, we have studied in detail the interaction of ionizing particles with LEKID (Lumped Element KID) arrays. We have constructed a dedicated cryogenic setup that allows to reproduce the typical observing conditions of a space-borne observatory. We will report the details and conclusions from a number of measurements. We give a brief description of our short term project, consisting in flying LEKID on a stratospheric balloon named B-SIDE.Comment: To appear in the SPIE 2016 Proceeding

Genome characterization and CRISPR-Cas9 editing of a human neocentromere

The maintenance of genome integrity is ensured by proper chromosome inheritance during mitotic and meiotic cell divisions. The chromosomal counterpart responsible for chromosome segregation to daughter cells is the centromere, at which the spindle apparatus attaches through the kinetochore. Although all mammalian centromeres are primarily composed of megabase-long repetitive sequences, satellite-free human neocentromeres have been described. Neocentromeres and evolutionary new centromeres have revolutionized traditional knowledge about centromeres. Over the past 20 years, insights have been gained into their organization, but in spite of these advancements, the mechanisms underlying their formation and evolution are still unclear. Today, through modern and increasingly accessible genome editing and long-read sequencing techniques, research in this area is undergoing a sudden acceleration. In this article, we describe the primary sequence of a previously described human chromosome 3 neocentromere and observe its possible evolution and repair results after a chromosome breakage induced through CRISPR-Cas9 technologies. Our data represent an exciting advancement in the field of centromere/neocentromere evolution and chromosome stability

Promoter methylation correlates with reduced NDRG2 expression in advanced colon tumour

<p>Abstract</p> <p>Background</p> <p>Aberrant DNA methylation of CpG islands of cancer-related genes is among the earliest and most frequent alterations in cancerogenesis and might be of value for either diagnosing cancer or evaluating recurrent disease. This mechanism usually leads to inactivation of tumour-suppressor genes. We have designed the current study to validate our previous microarray data and to identify novel hypermethylated gene promoters.</p> <p>Methods</p> <p>The validation assay was performed in a different set of 8 patients with colorectal cancer (CRC) by means quantitative reverse-transcriptase polymerase chain reaction analysis. The differential RNA expression profiles of three CRC cell lines before and after 5-aza-2'-deoxycytidine treatment were compared to identify the hypermethylated genes. The DNA methylation status of these genes was evaluated by means of bisulphite genomic sequencing and methylation-specific polymerase chain reaction (MSP) in the 3 cell lines and in tumour tissues from 30 patients with CRC.</p> <p>Results</p> <p>Data from our previous genome search have received confirmation in the new set of 8 patients with CRC. In this validation set six genes showed a high induction after drug treatment in at least two of three CRC cell lines. Among them, the N-myc downstream-regulated gene 2 (<it>NDRG2) </it>promoter was found methylated in all CRC cell lines. <it>NDRG2 </it>hypermethylation was also detected in 8 out of 30 (27%) primary CRC tissues and was significantly associated with advanced AJCC stage IV. Normal colon tissues were not methylated.</p> <p>Conclusion</p> <p>The findings highlight the usefulness of combining gene expression patterns and epigenetic data to identify tumour biomarkers, and suggest that NDRG2 silencing might bear influence on tumour invasiveness, being associated with a more advanced stage.</p

TRAM (Transcriptome Mapper): database-driven creation and analysis of transcriptome maps from multiple sources

<p>Abstract</p> <p>Background</p> <p>Several tools have been developed to perform global gene expression profile data analysis, to search for specific chromosomal regions whose features meet defined criteria as well as to study neighbouring gene expression. However, most of these tools are tailored for a specific use in a particular context (e.g. they are species-specific, or limited to a particular data format) and they typically accept only gene lists as input.</p> <p>Results</p> <p>TRAM (Transcriptome Mapper) is a new general tool that allows the simple generation and analysis of quantitative transcriptome maps, starting from any source listing gene expression values for a given gene set (e.g. expression microarrays), implemented as a relational database. It includes a parser able to assign univocal and updated gene symbols to gene identifiers from different data sources. Moreover, TRAM is able to perform intra-sample and inter-sample data normalization, including an original variant of quantile normalization (scaled quantile), useful to normalize data from platforms with highly different numbers of investigated genes. When in 'Map' mode, the software generates a quantitative representation of the transcriptome of a sample (or of a pool of samples) and identifies if segments of defined lengths are over/under-expressed compared to the desired threshold. When in 'Cluster' mode, the software searches for a set of over/under-expressed consecutive genes. Statistical significance for all results is calculated with respect to genes localized on the same chromosome or to all genome genes. Transcriptome maps, showing differential expression between two sample groups, relative to two different biological conditions, may be easily generated. We present the results of a biological model test, based on a meta-analysis comparison between a sample pool of human CD34+ hematopoietic progenitor cells and a sample pool of megakaryocytic cells. Biologically relevant chromosomal segments and gene clusters with differential expression during the differentiation toward megakaryocyte were identified.</p> <p>Conclusions</p> <p>TRAM is designed to create, and statistically analyze, quantitative transcriptome maps, based on gene expression data from multiple sources. The release includes FileMaker Pro database management runtime application and it is freely available at <url>http://apollo11.isto.unibo.it/software/</url>, along with preconfigured implementations for mapping of human, mouse and zebrafish transcriptomes.</p

The commissioning of the CUORE experiment: the mini-tower run

CUORE is a ton-scale experiment approaching the data taking phase in Gran Sasso National Laboratory. Its primary goal is to search for the neutrinoless double-beta decay in 130Te using 988 crystals of tellurim dioxide. The crystals are operated as bolometers at about 10 mK taking advantage of one of the largest dilution cryostat ever built. Concluded in March 2016, the cryostat commissioning consisted in a sequence of cool down runs each one integrating new parts of the apparatus. The last run was performed with the fully configured cryostat and the thermal load at 4 K reached the impressive mass of about 14 tons. During that run the base temperature of 6.3 mK was reached and maintained for more than 70 days. An array of 8 crystals, called mini-tower, was used to check bolometers operation, readout electronics and DAQ. Results will be presented in terms of cooling power, electronic noise, energy resolution and preliminary background measurements

Results from the Cuore Experiment

The Cryogenic Underground Observatory for Rare Events (CUORE) is the first bolometric experiment searching for neutrinoless double beta decay that has been able to reach the 1-ton scale. The detector consists of an array of 988 TeO2 crystals arranged in a cylindrical compact structure of 19 towers, each of them made of 52 crystals. The construction of the experiment was completed in August 2016 and the data taking started in spring 2017 after a period of commissioning and tests. In this work we present the neutrinoless double beta decay results of CUORE from examining a total TeO2 exposure of 86.3kg yr, characterized by an effective energy resolution of 7.7 keV FWHM and a background in the region of interest of 0.014 counts/ (keV kg yr). In this physics run, CUORE placed a lower limit on the decay half- life of neutrinoless double beta decay of 130Te > 1.3.1025 yr (90% C. L.). Moreover, an analysis of the background of the experiment is presented as well as the measurement of the 130Te 2vo3p decay with a resulting half- life of T2 2. [7.9 :- 0.1 (stat.) :- 0.2 (syst.)] x 10(20) yr which is the most precise measurement of the half- life and compatible with previous results

Applications des détecteurs à inductance cinétique pour l'Astronomie et la Physique des particules

Kinetic Inductance Detectors (KID) have recently drawn the attention of the low-temperature detectors community. High sensitivity, low fabrication complexity, small time constant and most notably the intrinsic capability of frequency multiplexed readout open new possibilities for experiments which need large format arrays of ultra sensitive light detectors. In millimeter Astronomy, the New IRAM KID Array (NIKA) instrument is today the most beautiful demonstration of this statement. It is a two bands hundreds-pixels KID based camera permanently installed at the focal plane of the IRAM 30-m telescope of Pico Veleta (Granada, Spain). Thanks to the NIKA observational campaign, we have de nitively demonstrated performances comparable to the state-of-art of bolometers and the instrument is today opened to the astronomers community. This encourages further array scaling and opens the path to next generation kilo-pixels ground-based cameras, like NIKA-2. Moreover, the will to extend KID technology to space mission needs the interaction with cosmic rays to be investigated. The understanding of the physics behind substrate-higher energy particles interactions led us to implement a fully independent system for the phonon-mediated particle detection with KID arrays. The work carried out through this PhD thesis concerned the development of optimized Lumped Element Kinetic Inductance Detectors (LEKID) and the implementation of dedicated readout techniques for the aforementioned activities.Les Détecteurs a Inductance Cinétique (KID) ont récemment attiré l'attention de la communauté des détecteurs fonctionnants à très basse température (~100 mK). Haute sensibilité, une fabrication simple, une lecture à faible constante de temps et un multiplexage fréquentielle intrinsèque, ouvrent de nouvelles possibilités pour les expériences necessitant des matrices de détecteurs ultra-sensibles avec un grand nombre de pixels. En astronomie millimétrique, l'instrument New IRAM KID Array (NIKA) est aujourd'hui la meilleure démonstration des performances optiques des ces détecteurs. Cette dernière est composée de plusieurs centaines des KIDs répartis sur deux bandes spectrales. NIKA est installé de manière permanente au telescope (30 mètres) IRAM à Pico Veleta (Grenade, Espagne). Pendant les campagnes d'observation NIKA, nous avons démontré des performances comparables aux bolomètres et l'instrument est aujourd'hui ouvert à la communauté des astronomes. Ces résultats favorables ont déclenché le développement d'une géneration plus ambitieuse : NIKA2. Cette dernière fonctionnera avec pas moins de quelques ~5000 pixels. De plus, il existe une volonté d'étendre la technologie de KID pour les futures missions spatiales d'observation. Dans ce cadre, il est important d'étudier l'interaction des rayons cosmiques avec les matrices de KIDs. Nous avons réalisé une étude avancée permettant aujourd'hui d'entrevoire la physique derrière les intéractions à haute énergie dans les substrats et leur propagation sous forme de phonons jusque dans les pixels. Le travail effectué dans cette thèse est centré principalement sur le développement des instruments (les matrices des detecteurs et le software de lecture et acquisition des donnes) dédiés aux KIDs pour ces mesures

Swelling of CFx and CFx(Au) films

The article reports on the swelling phenomenon, observed in the presence of acetone vapors in undoped and Au doped Teflon-like films. The Au presence enhances the degree of the swelling of the Teflon. Moreover, the metal grains embedded in the insulating matrix are used to detect swelling with an electrical method. A conductance model of metal embedded dielectric materials is used to describe the conductance variations with the polymer volume change. (C) 2000 American Institute of Physics. [S0021-8979(00)05504-3]

Diversity and dynamics of an interstitial Tardigrada population in the Meloria Shoals, Liguria Sea, with a redescription of Batellipes similis (Heterotardigrada, Batillipedidae)

Quantitative samples of sediment for tbc study of the meiofauna were collected monthly beween March 1996 and February 1997 from a 7-m-deep site in tbc Meloria Shoals, Livorno Italy. In tbc Tuscan Shoals, 16 species of tardigrades were found belonging to tbc families Stygarctidae, Halechiniscidae, and Batillipedidac. Megastygarctides orbiculatus and Actinarctus doryPborus are reported for tbc first time in tbc Mediterranean Sea, and a redescription of Batillipes similis is proposed. Global density of . tbc Tardigrada population fluctuated between 8 ind./10 cm2 in May 1996 and 285 ind./10 cm2 in January 1997. The lowest valite of tbc Shannon-Wiener biodiversity index (H' = 1.09) was found in September 1996, whereas the highest score (H' = 2.46) was obtamed in March 1996. Pielou's evenness index (J) fluctuated between 0.40 and 0.88, values attamed in January 1997 and March 1996, respectively. The study confirms the notion that tbc organogenic detritus of the Shoals represents a very favourable environment for meiofauna) organisms in generai, and Tardigrada in particular

Identification of Bari Transposons in 23 Sequenced Drosophila Genomes Reveals Novel Structural Variants, MITEs and Horizontal Transfer.

Bari elements are members of the Tc1-mariner superfamily of DNA transposons, originally discovered in Drosophila melanogaster, and subsequently identified in silico in 11 sequenced Drosophila genomes and as experimentally isolated in four non-sequenced Drosophila species. Bari-like elements have been also studied for their mobility both in vivo and in vitro. We analyzed 23 Drosophila genomes and carried out a detailed characterization of the Bari elements identified, including those from the heterochromatic Bari1 cluster in D. melanogaster. We have annotated 401 copies of Bari elements classified either as putatively autonomous or inactive according to the structure of the terminal sequences and the presence of a complete transposase-coding region. Analyses of the integration sites revealed that Bari transposase prefers AT-rich sequences in which the TA target is cleaved and duplicated. Furthermore evaluation of transposon's co-occurrence near the integration sites of Bari elements showed a non-random distribution of other transposable elements. We also unveil the existence of a putatively autonomous Bari1 variant characterized by two identical long Terminal Inverted Repeats, in D. rhopaloa. In addition, we detected MITEs related to Bari transposons in 9 species. Phylogenetic analyses based on transposase gene and the terminal sequences confirmed that Bari-like elements are distributed into three subfamilies. A few inconsistencies in Bari phylogenetic tree with respect to the Drosophila species tree could be explained by the occurrence of horizontal transfer events as also suggested by the results of dS analyses. This study further clarifies the Bari transposon's evolutionary dynamics and increases our understanding on the Tc1-mariner elements' biology