About Quartz Crystal Resonator Noise: Recent Study

The first step, before investigating physical origins of noise in resonators, is to investigate correlations between external measurement parameters and the resonator noise. Tests and measurements are mainly performed on an advanced phase noise measurement system, recently set up. The resonator noise is examined as a function of the sensitivity to the drive level, the temperature operating point and the tuning capacitor.Comment: 20th International Conference on Noise and Fluctuations, Pisa : Italie (2009

A prognostic six-gene expression risk-score derived from proteomic profiling of the metastatic colorectal cancer secretome

14 p.-6 fig.-1 tab.The necessity to accurately predict recurrence and clinical outcome in early stage colorectal cancer (CRC) is critical to identify those patients who may benefit from adjuvant chemotherapy. Here, we developed and validated a gene-based risk-score algorithm for patient stratification and personalised treatment in early stage disease based on alterations in the secretion of metastasis-related proteins. A quantitative label-free proteomic analysis of the secretome of highly and poorly metastatic CRC cell lines with different genetic backgrounds revealed 153 differentially secreted proteins (fold-change >5). These changes in the secretome were validated at the transcriptomic level. Starting from 119 up-regulated proteins, a six-gene/protein-based prognostic signature composed of IGFBP3, CD109, LTBP1, PSAP, BMP1, and NPC2 was identified after sequential discovery, training,and validation in four different cohorts. This signature was used to develop a risk-score algorithm, named SEC6,for patient stratification. SEC6 risk-score components showed higher expression in the poor prognosis CRC sub types: consensus molecular subtype 4 (CMS4), CRIS-B, and stem-like. High expression of the signature was also associated with patients showing dMMR, CIMP+ status, and BRAF mutations. In addition, the SEC6 signature was associated with lower overall survival, progression-free interval, and disease-specific survival in stage II and III patients. SEC6-based risk stratification indicated that 5-FU treatment was beneficial for low-risk patients,whereas only aggressive treatments (FOLFOX and FOLFIRI) provided benefits to high-risk patients in stages II and III. In summary, this novel risk-score demonstrates the value of the secretome compartment as a reliable source for the retrieval of biomarkers with high prognostic and chemotherapy-predictive capacity, providing a potential new tool for tailoring decision-making in patient care.This project was supported by grants RTI2018-095055-B-100 and PID2021-122227OB-I00 from the MICYT, IND2019/BMD-17153 from the Comunidad de Madrid and PRB3 (ISCIII-SGEFI/FEDER- PT17/0019/0008) from the ISCIII.Peer reviewe

Carrier suppression system to measure phase noise of acoustic resonators with low motional resistance

International audienceA carrier suppression system is implemented in order to measure the phase noise of acoustic resonators that have a low motional resistance. A special adapters’ system using transformers is proposed to improve the loaded quality factor of the resonators. With this developed device and described protocol, the inherent noise of resonators can be obtained without the usual electronical oscillator conditioning that could take part in the results. The loaded quality factor is improved from about 10% to 60% of the intrinsic quality factor. As an example, the system is used to study Langatate crystal resonators vibrating at 10 MHz. Langatate crystals can be an alternative to substitute for the quartz crystal resonators for frequency and time applications. Their coupling coefficient and the product quality factor-frequency are normally higher than those in quartz crystal resonators. For ultrastable resonators, the motional resistance obtained with Langatate crystals is about five times lower than that for the quartz crystal; it can reach typically few ohms. These resonators have been characterized in terms of impedance, Q-factors, turnover temperature, amplitude–frequency effect, and phase noise. The short-term stability of these resonators is given in terms of Allan standard deviation. The influence of the driving power is presente

Losses in high quality quartz crystal resonators at cryogenic temperatures

International audienceMeasurement of the mechanical losses of quartz crystal is a topic of interest for communities dealing with the gravitational wave detectors and also the time and frequency domain. About the latter, the authors describe Q-factor measurements of quartz crystal resonators at cryogenic temperatures under 10 K, thanks to a cryocooler-based experimental set-up. A Q-factor of 325 millions at 4 K, on the fifth overtone of the quasilongitudinal mode at 15.9 MHz, has been recorded. As shown, the acoustic wave trapping is suspected to limit the Landau-Rumer regime below 6 K [Landau and Rumer, Phys. Z. Sowjetunion 11, 18 (1937)]

Development of a 10 MHz Oscillator Working with an LGT Crystal Resonator : Preliminary results

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SOSTDC1 promotes invasion and liver metastasis in colorectal cancer via interaction with ALCAM/CD166

38 p.-7 fig.The mechanistic basis of liver metastasis in colorectal cancer remains poorly understood. We previously reported that the sclerostin domain containing-1 (SOSTDC1) protein is overexpressed in the secretome of metastatic colorectal cancer cells and can inhibit liver homing. Here, we investigated the mechanisms of SOSTDC1 for promoting invasiveness and progression of colorectal cancer liver metastasis. SOSTDC1 inhibition of BMP4 maintains the expression of cancer stem cell traits, including SOX2 and NANOG. Immunoprecipitation and mass spectrometry analyses reveal the association of SOSTDC1 with ALCAM/CD166, which was confirmed by confocal microscopy and competition ELISA. Interaction with ALCAM is mediated by the N-terminal region of SOSTDC1, which contains a sequence similar to the ALCAM-binding motif used by CD6. Knocking down either SOSTDC1 or ALCAM expression, or using blocking antibodies, reduces the invasive activity by inhibiting Src and PI3K/AKT signaling pathways. In addition, ALCAM interacts with the alpha2SS1 and alpha1SS1 integrins, providing a possible link to Src activation. Finally, inoculation of SOSTDC1-silenced metastatic cells increases mouse survival by inhibiting liver metastasis. In conclusion, SOSTDC1 promotes invasion and liver metastasis in colorectal cancer, by overcoming BMP4-specific antimetastatic signals and inducing ALCAM-mediated Src and PI3K/AKT activation. These experiments underscore the potential of SOSTDC1 as a therapeutic target in metastatic colorectal cancer.This research was supported by grants from the Ministerio de Ciencia e Innovación (BIO2015-66489-R, RTI2018-095055-B100), Foundation Ramón Areces and PRB3 (ISCIII-SGEFI/FEDER-PT17/0019/0008).Peer reviewe

Extraction des contours de la texture musculaire animale à l'aide d'algorithmes linéaires et morphologiques

Nous décrivons dans cet article une combinaison d'opérateurs linéaires classiques d'extraction de contour et d'opérateurs morphologiques permettant d'apporter une solution à des problèmes liés à l'acquisition d'images par un processeur de vision. A l'aide de ces algorithmes, implantés sur notre Processeur d'Images Vidéo d'Evaluation, nous avons pu obtenir une binarisation correcte de la trame conjonctive d'une coupe transversale microscopique de muscle sur support photographique vue à travers une caméra vidéo standard

Quartz crystals resonators exhibiting extremaly high Q-factor at cryogenic temperatures

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