Probabilistic Work Extraction on a Classical Oscillator Beyond the Second Law.

We demonstrate experimentally that, applying optimal protocols that drive the system between two equilibrium states characterized by a free energy difference ΔF, we can maximize the probability of performing the transition between the two states with a work W smaller than ΔF. The second law holds only on average, resulting in the inequality ⟨W⟩≥ΔF. The experiment is performed using an underdamped oscillator evolving in a double-well potential.

Role of a capping layer on the crystalline structure of Sn thin films grown at cryogenic temperatures on InSb substrates.

Metal deposition with cryogenic cooling is a common technique in the condensed matter community for producing ultra-thin epitaxial superconducting layers on semiconductors. However, a significant challenge arises when these films return to room temperature, as they tend to undergo dewetting. This issue can be mitigated by capping the films with an amorphous layer.

Adiabatic computing for optimal thermodynamic efficiency of information processing.

Landauer's principle makes a strong connection between information theory and thermodynamics by stating that erasing a one-bit memory at temperature [Formula: see text] requires an average energy larger than [Formula: see text], with [Formula: see text] Boltzmann's constant. This tiny limit has been saturated in model experiments using quasistatic processes. For faster operations, an overhead proportional to the processing speed and to the memory damping appears.

Logical and thermodynamical reversibility: Optimized experimental implementation of the not operation.

The not operation is a reversible transformation acting on a 1-bit logical state and should be achievable in a physically reversible manner at no energetic cost. We experimentally demonstrate a bit-flip protocol based on the momentum of an underdamped oscillator confined in a double-well potential. The protocol is designed to be reversible in the ideal dissipationless case, and the thermodynamic work required is inversely proportional to the quality factor of the system.

Linking fluctuation and dissipation in spatially extended out-of-equilibrium systems.

For systems in equilibrium at a temperature T, thermal noise and energy damping are related to T through the fluctuation-dissipation theorem (FDT). We study here an extension of the FDT to an out-of-equilibrium steady state: a microcantilever subject to a constant heat flux. The resulting thermal profile in this spatially extended system interplays with the local energy dissipation field to prescribe the amplitude of mechanical fluctuations.

Dynamics of Information Erasure and Extension of Landauer's Bound to Fast Processes.

Using a double-well potential as a physical memory, we study with experiments and numerical simulations the energy exchanges during erasure processes, and model quantitatively the cost of fast operation. Within the stochastic thermodynamics framework we find the origins of the overhead to Landauer's bound required for fast operations: in the overdamped regime this term mainly comes from the dissipation, while in the underdamped regime it stems from the heating of the memory. Indeed, the system is thermalized with its environment at all times during quasistatic protocols, but for fast ones, the inefficient heat transfer to the thermostat is delayed with respect to the work influx, resulting in a transient temperature rise.

PdSpermine Complex Shows Cancer Selectivity and Efficacy to Inhibit Growth of Triple-Negative Breast Tumors in Mice.

PdSpm is a dinuclear palladium(II)-spermine chelate with promising anticancer properties against triple-negative breast cancer (TNBC), a breast carcinoma subset with poor prognosis and limited treatment options. The present study evaluated the in vitro and in vivo anticancer effects of PdSpm compared to the reference metal-based drug cisplatin. Triple-negative breast cancer MDA-MB-231 cells, non-cancerous MCF-12A breast cells and chorioallantoic membrane (CAM) assay were used for antiproliferative, antimigratory and antiangiogenic studies.

Thermal noise of a cryocooled silicon cantilever locally heated up to its melting point.

The Fluctuation-Dissipation Theorem (FDT) is a powerful tool to estimate the thermal noise of physical systems in equilibrium. In general, however, thermal equilibrium is an approximation or cannot be assumed at all. A more general formulation of the FDT is then needed to describe the behavior of the fluctuations.

Information and Thermodynamics: Fast and Precise Approach to Landauer's Bound in an Underdamped Micromechanical Oscillator.

The Landauer principle states that at least k_{B}Tln2 of energy is required to erase a 1-bit memory, with k_{B}T the thermal energy of the system. We study the effects of inertia on this bound using as one-bit memory an underdamped micromechanical oscillator confined in a double-well potential created by a feedback loop. The potential barrier is precisely tunable in the few k_{B}T range.

Large colloidal probes for atomic force microscopy: Fabrication and calibration issues.

Atomic force microscopy (AFM) is a powerful tool to investigate interaction forces at the micro and nanoscale. Cantilever stiffness, dimensions and geometry of the tip can be chosen according to the requirements of the specific application, in terms of spatial resolution and force sensitivity. Colloidal probes (CPs), obtained by attaching a spherical particle to a tipless (TL) cantilever, offer several advantages for accurate force measurements: tunable and well-characterisable radius; higher averaging capabilities (at the expense of spatial resolution) and sensitivity to weak interactions; a well-defined interaction geometry (sphere on flat), which allows accurate and reliable data fitting by means of analytical models.

Detecting protein folding by thermal fluctuations of microcantilevers.

The accurate characterization of proteins in both their native and denatured states is essential to effectively understand protein function, folding and stability. As a proof of concept, a micro rheological method is applied, based on the characterization of thermal fluctuations of a micro cantilever immersed in a bovine serum albumin solution, to assess changes in the viscosity associated with modifications in the protein's structure under the denaturant effect of urea. Through modeling the power spectrum density of the cantilever's fluctuations over a broad frequency band, it is possible to implement a fitting procedure to accurately determine the viscosity of the fluid, even at low volumes.

Disparities in reproductive outcomes according to the endometrial preparation protocol in frozen embryo transfer : The risk of early pregnancy loss in frozen embryo transfer cycles.

Purpose: The purpose of this study was to determine the effect of stimulated and artificial endometrial preparation protocols on reproductive outcomes in frozen embryo transfer (FET) cycles.

Methods: We performed a retrospective study of 1926 FET cycles over a 3.5-year period in the Fertility Unit at a University Hospital.

Low thermal fluctuations in a system heated out of equilibrium.

We study the mechanical fluctuations of a micrometer sized silicon cantilever subjected to a strong heat flow, thus having a highly nonuniform local temperature. In this nonequilibrium steady state, we show that fluctuations are equivalent to the thermal noise of a cantilever at equilibrium around room temperature, while its mean local temperature is several hundred degrees higher. Changing the mechanical dissipation by adding a coating to the cantilever, we recover the expected rise of fluctuations with the mean temperature.

High Resolution Viscosity Measurement by Thermal Noise Detection.

An interferometric method is implemented in order to accurately assess the thermal fluctuations of a micro-cantilever sensor in liquid environments. The power spectrum density (PSD) of thermal fluctuations together with Sader's model of the cantilever allow for the indirect measurement of the liquid viscosity with good accuracy. The good quality of the deflection signal and the characteristic low noise of the instrument allow for the detection and corrections of drawbacks due to both the cantilever shape irregularities and the uncertainties on the position of the laser spot at the fluctuating end of the cantilever.

Simultaneous and accurate measurement of the dielectric constant at many frequencies spanning a wide range.

We present an innovative technique which allows the simultaneous measurement of the dielectric constant of a material at many frequencies, spanning a four orders of magnitude range chosen between 10(-2) Hz and 10(4) Hz. The sensitivity and accuracy are comparable to those obtained using standard single frequency techniques. The technique is based on three new and simple features: (a) the precise real time correction of the amplification of a current amplifier, (b) the specific shape of the excitation signal and its frequency spectrum, and (c) the precise synchronization between the generation of the excitation signal and the acquisition of the dielectric response signal.

Development and preliminary evaluation of a 90 K Axiom® SNP array for the allo-octoploid cultivated strawberry Fragaria × ananassa.

Background: A high-throughput genotyping platform is needed to enable marker-assisted breeding in the allo-octoploid cultivated strawberry Fragaria × ananassa. Short-read sequences from one diploid and 19 octoploid accessions were aligned to the diploid Fragaria vesca 'Hawaii 4' reference genome to identify single nucleotide polymorphisms (SNPs) and indels for incorporation into a 90 K Affymetrix® Axiom® array. We report the development and preliminary evaluation of this array.

Evaluation of urinary dysfunction by urodynamic tests, electromyography and quality of life questionnaire before and after surgery for deep infiltrating endometriosis.

Objective: To evaluate urinary dysfunction and quality of life before and after surgery for deep infiltrating endometriosis (DIE).

Methods: This prospective study included 50 patients with DIE who required surgery. Urinary dysfunction was evaluated before and after surgery by both urodynamic tests and electromyography, and the Bristol Female Lower Urinary Tract Symptoms (BFLUTS) quality-of-life questionnaire.

Quadrature phase interferometer for high resolution force spectroscopy.

In this article, we present a deflection measurement setup for Atomic Force Microscopy (AFM). It is based on a quadrature phase differential interferometer: we measure the optical path difference between a laser beam reflecting above the cantilever tip and a reference beam reflecting on the static base of the sensor. A design with very low environmental susceptibility and another allowing calibrated measurements on a wide spectral range are described.

Functionalized AFM probes for force spectroscopy: eigenmode shapes and stiffness calibration through thermal noise measurements.

The functionalization of an atomic force microscope (AFM) cantilever with a colloidal bead is a widely used technique when the geometry between the probe and the sample must be controlled, particularly in force spectroscopy. But some questions remain: how does a bead glued at the end of a cantilever influence its mechanical response? And more importantly for quantitative measurements, can we still determine the stiffness of the AFM probe with traditional techniques?In this paper, the influence of the colloidal mass loading on the eigenmode shape and resonant frequency is investigated by measuring the thermal noise on rectangular AFM microcantilevers with and without beads attached at their extremities. The experiments are performed with a home-made ultra-sensitive AFM, based on differential interferometry.

Frequency dependence of viscous and viscoelastic dissipation in coated micro-cantilevers from noise measurement.

We measure the mechanical thermal noise of soft silicon atomic force microscope cantilevers. Using an interferometric setup, we obtain a resolution down to 10(-14) m Hz(-1/2) on a wide spectral range (3-10(5) Hz). The low frequency behavior depends dramatically on the presence of a reflective coating: almost flat spectra for uncoated cantilevers versus a 1/f like trend for coated ones.

Oligoribonucleotides with 2'-O-(tert-butyldimethylsilyl) groups.

The chemical synthesis of oligoribonucleotides on solid support is routinely performed via the phosphoramidite method. However, the additional 2-OH function of the ribofuranosyl sugar requires suitable protection during oligoribonucleotide synthesis. This unit describes methods for 2-OH protection using the TBDMS group.

Low-level arsenite activates the transcription of genes involved in adipose differentiation.

In this study we analyzed gene expression in 3T3-F442A pre-adipocyte cells that differentiate in the presence of micro-molar arsenate concentration. Two concentrations of arsenite (As2O3, 0.25 micromol/L and 0.

Ribozyme targeting of the growth factor pleiotrophin in established tumors: a gene therapy approach.

The growth and metastasis of solid tumors relies on the activities of polypeptide growth factors to recruit stromal tissue and expand the tumor mass. Pleiotrophin (PTN) is a secreted growth factor with angiogenic activity that has been found to contribute to the growth and metastasis of tumors including melanoma. Here, we present a gene therapy approach of targeting PTN in established tumors using ribozymes.