6 research outputs found
In-plane nanoelectromechanical resonators based on silicon nanowire piezoresistive detection
We report an actuation/detection scheme with a top-down
nano-electromechanical system for frequency shift-based sensing applications
with outstanding performance. It relies on electrostatic actuation and
piezoresistive nanowire gauges for in-plane motion transduction. The process
fabrication is fully CMOS compatible. The results show a very large dynamic
range (DR) of more than 100dB and an unprecedented signal to background ratio
(SBR) of 69dB providing an improvement of two orders of magnitude in the
detection efficiency presented in the state of the art in NEMS field. Such a
dynamic range results from both negligible 1/f-noise and very low Johnson noise
compared to the thermomechanical noise. This simple low-power detection scheme
paves the way for new class of robust mass resonant sensor
Current blockade in classical single-electron nanomechanical resonator
International audienceWe consider a single-electron transistor where the central metallic island can oscillate. It has been shown that for a weak coupling of the elastic and electric degrees of freedom, the position of the island fluctuates with a small variation of the current through the device. In this paper, we consider the strong coupling limit. We show that the system undergoes a static mechanical instability that is responsible for the opening of a gap in the current-voltage characteristics even at the degeneracy point. We provide an analytical description of the transition point, taking into account the nonequilibrium mechanical state. We also discuss how the mechanical nature of the suppression of the current can be probed experimentally by a slow modulation of the gate voltage
WEPLATE WP8 6DOF ALIGNMENT PLATFORM
In the context of the LHC (Large Hadron Collider) upgrade at CERN (European Organization for Nuclear Research) known as HL-LHC (High Luminosity LHC) which will increase the LHC luminosity (rate of collisions) by a factor of five beyond the original design value and the integrated luminosity (total collisions created) by a factor ten, WP8 (Work Package 8) proposed a new alignment platform concept for the alignment of TANB (Target Absorber Neutrals) being installed in LS2 (Long Shutdown 2) at Point 8. The increase of luminosity expected at Point 8 will create a shower of secondary forward particles, namely of neutrals (mostly neutrons and photons) and charged particles (mostly pions and protons), that will leave the interaction point 8 in both directions towards the machine creating a non-negligible energy deposition in the region. TANB main function will be as a protective absorber for the dipole D2. This continuous deposition during HL-LHC Run 3 and Run 4 will activate the TANB rendering any human activity in the region conditioned to very strict and short timed periods. Among this activities alignment is placed as one of the most time consuming and one that obliges a closer proximity with the TANB absorber mainly due to the current design of the “standard” CERN alignment platforms. Inserted in the ALARA (As Low As Reasonably Achievable) approach the new alignment platform presented takes the design of the “standard” CERN alignment platform and through simple modifications moves the actuators for each degree of freedom to the foreseen intervention side facilitating its access, improving the ergonomics of the alignment operations and principally decreasing the alignment operation time for the equipment mitigating the exposure of the professionals to the activated area
Imatinib combined with induction or consolidation chemotherapy in patients with de novo Philadelphia chromosome-positive acute lymphoblastic leukemia: results of the GRAAPH-2003 study
The combination of imatinib with chemotherapy has been recently reported as very promising in patients with Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL). During 2004 and 2005, 45 patients with newly diagnosed Ph+ ALL were treated in the Group for Research on Adult Acute Lymphoblastic Leukemia (GRAAPH) 2003 study, in which imatinib was started with HAM (mitoxantrone with intermediatedose cytarabine) consolidation in good early responders (corticosensitive and chemosensitive ALL) or earlier during the induction course in combination with dexamethasone and vincristine in poor early responders (corticoresistant and/or chemoresistant ALL). Imatinib was then continuously administered until stem cell transplantation (SCT). Overall, complete remission (CR) and BCR-ABL real-time quantitative polymerase chain reaction (RO-PCR) negativity rates were 96% and 29%, respectively. All of the 22 CR patients (100%) with a donor actually received allogeneic SCT in first CR. At 18 months, the estimated cumulative incidence of relapse, disease-free survival, and overall survival were 30%, 51 %, and 65%, respectively. These 3 end points compared very favorably with results obtained in the pre-imatinib LALA-94 trial. This study confirms the value of the combined approach and encourages prospective trials to define the optimal chemotherapy that has to be combined with imatinib and to carefully reevaluate the place of allogeneic SCT in this new context
Long-Term Results of the Imatinib GRAAPH-2003 Study in Newly-Diagnosed Patients with De Novo Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia
French coastal network for carbonate system monitoring: The CocoriCO2 dataset
Since the beginning of the industrial revolution, atmospheric carbon dioxide (CO2) concentrations have risen steadily and have induced a decrease of the averaged surface ocean pH by 0.1 units, corresponding to an increase in ocean acidity of about 30 %. In addition to ocean warming, ocean acidification poses a tremendous challenge to some marine organisms, especially calcifiers. The need for long-term oceanic observations of pH and temperature is a key element to assess the vulnerability of marine communities and ecosystems to these pressures. Nearshore productive environments, where a large majority of shellfish farming activities are conducted, are known to present pH levels as well as amplitudes of daily and seasonal variations that are much larger than those observed in the open ocean. Yet, to date, there are very few coastal observation sites where these parameters are measured simultaneously and at high frequency. To bridge this gap, an observation network was initiated in 2021 in the framework of the CocoriCO(2) project. Six sites were selected along the French Atlantic and Mediterranean coastlines based on their importance in terms of shellfish production and the presence of high- and low-frequency monitoring activities. At each site, autonomous pH sensors were deployed, both inside and outside shellfish production areas, next to high-frequency CTD (conductivity-temperature-depth) probes operated through two operating monitoring networks. pH sensors were set to an acquisition rate of 15 min, and discrete seawater samples were collected biweekly in order to control the quality of pH data (laboratory spectrophotometric measurements) as well as to measure total alkalinity and dissolved inorganic carbon concentrations for full characterization of the carbonate system. While this network has been up and running for more than 2 years, the acquired dataset has already revealed important differences in terms of pH variations between monitored sites related to the influence of diverse processes (freshwater inputs, tides, temperature, biological processes). Data are available at 10.17882/96982 (Petton et al., 2023a)