Inter-combination line frequencies in Yb validated with the clock transition: erratum.

This erratum corrects an error in Appl. Opt.62, 3932 (2023)APOPAI0003-693510.

Bone marrow fibrosis is associated with non-response to CD19 CAR T-cell therapy in B-acute lymphoblastic leukemia.

CD19 directed CAR T-cell therapy is used to treat relapsed/refractory B-cell acute lymphoblastic leukemia. The role of the pre-CAR bone marrow (BM) stromal microenvironment in determining response to CAR T-cell therapy has been understudied. We performed whole transcriptome analysis, reticulin fibrosis assessment and CD3 T-cell infiltration on BM core biopsies from pre- and post-CAR timepoints for 61 patients, as well as on a cohort of 54 primary B-ALL samples.

Intercombination line frequencies in Yb validated with the clock transition.

We have carried absolute frequency measurements of the (6 ) -(66) transition in (intercombination line), where the spin-1/2 isotope yields two hyperfine lines. The measurements rely on sub-Doppler spectroscopy to yield a discriminator to which a 556 nm laser is locked. The frequency reference for the optical frequency measurements is a high-quality quartz oscillator steered to the GNSS time scale that is bridged with a frequency comb.

Repair of Acute Respiratory Distress Syndrome in COVID-19 by Stromal Cells (REALIST-COVID Trial): A Multicenter, Randomized, Controlled Clinical Trial.

Mesenchymal stromal cells (MSCs) may modulate inflammation, promoting repair in coronavirus disease (COVID-19)-related acute respiratory distress syndrome (ARDS). We investigated the safety and efficacy of ORBCEL-C (CD362 [cluster of differentiation 362]-enriched, umbilical cord-derived MSCs) in COVID-19-related ARDS. In this multicenter, randomized, double-blind, allocation-concealed, placebo-controlled trial (NCT03042143), patients with moderate to severe COVID-19-related ARDS were randomized to receive ORBCEL-C (400 million cells) or placebo (Plasma-Lyte 148).

Repair of acute respiratory distress syndrome by stromal cell administration (REALIST): a structured study protocol for an open-label dose-escalation phase 1 trial followed by a randomised, triple-blind, allocation concealed, placebo-controlled phase 2 trial.

Background: Mesenchymal stromal cells (MSCs) may be of benefit in ARDS due to immunomodulatory and reparative properties. This trial investigates a novel CD362 enriched umbilical cord derived MSC product (REALIST ORBCEL-C), produced to Good Manufacturing Practice standards, in patients with moderate to severe ARDS due to COVID-19 and ARDS due to other causes.

Methods: Phase 1 is a multicentre open-label dose-escalation pilot trial.

Repair of acute respiratory distress syndrome by stromal cell administration (REALIST) trial: A phase 1 trial.

Background: Mesenchymal stromal cells (MSCs) may be of benefit in acute respiratory distress syndrome (ARDS) due to immunomodulatory, reparative, and antimicrobial actions. ORBCEL-C is a population of CD362 enriched umbilical cord-derived MSCs. The REALIST phase 1 trial investigated the safety and feasibility of ORBCEL-C in patients with moderate to severe ARDS.

Repair of Acute Respiratory Distress Syndrome by Stromal Cell Administration in COVID-19 (REALIST-COVID-19): A structured summary of a study protocol for a randomised, controlled trial.

Objectives: The primary objective of the study is to assess the safety of a single intravenous infusion of Mesenchymal Stromal Cells (MSCs) in patients with Acute Respiratory Distress Syndrome (ARDS) due to COVID-19. Secondary objectives are to determine the effects of MSCs on important clinical outcomes, as described below.

Trial Design: REALIST COVID 19 is a randomised, placebo-controlled, triple blinded trial.

Optical frequency stabilization with a synchronous frequency-to-voltage converter.

Between a frequency comb mode and a continuous-wave (cw) laser, we demonstrate that a frequency-to-voltage converter can be used to transfer frequency instability in the 10 range for integration times τ between 0.25 and 2100 s. The technique is relevant when the optical beat between laser signals is weak and a high level of frequency stability is required both in the short term and long term, as in the case of laser cooling with very narrow transitions.

Laser stabilization with a frequency-to-voltage chip for narrow-line laser cooling.

We use integrated circuit-based frequency-to-voltage conversion of a frequency comb beat signal as the means for laser frequency stabilization that is suitable for narrow-line laser cooling. The method is compared to an atomic beam lock where the laser frequency instability for the new scheme shows an improvement of 2 orders of magnitude at sub-1 s and grants a lock-capture range that is approximately 30 times greater. We employ the locking method on a 1111.

Laser locking to the 199Hg 1S0-3P0 clock transition with 5.4 × 10(-15)/✓τ fractional frequency instability.

With 199Hg atoms confined in an optical lattice trap in the Lamb-Dicke regime, we obtain a spectral line at 265.6 nm for which the FWHM is ~15 Hz. Here we lock an ultrastable laser to this ultranarrow 1S0-3P0 clock transition and achieve a fractional frequency instability of 5.

Neutral atom frequency reference in the deep ultraviolet with fractional uncertainty = 5.7×10(-15).

We present an assessment of the (6s2) (1)S0 ↔ (6s6p)(3)P0 clock transition frequency in 199Hg with an uncertainty reduction of nearly 3 orders of magnitude and demonstrate an atomic quality factor Q of ∼10(14). The 199Hg atoms are confined in a vertical lattice trap with light at the newly determined magic wavelength of 362.5697±0.

Optical lattice trapping of 199Hg and determination of the magic wavelength for the ultraviolet 1S(0)↔3P(0) clock transition.

We report on the Lamb-Dicke spectroscopy of the doubly forbidden (6s(2))(1)S(0)↔(6s6p)(3)P(0) transition in (199)Hg atoms confined to a vertical 1D optical lattice. With lattice trapping of ≲10(3) atoms and a 265.6 nm probe laser linked to the LNE-SYRTE primary frequency reference we have determined the center frequency of the transition for a range of lattice wavelengths and at two lattice trap depths.

Sub-Doppler cooling of fermionic Hg isotopes in a magneto-optical trap.

Laser cooling and trapping of neutral mercury is performed in a single-stage (1)S(0)↔(3)P(1) 3D magneto-optical trap. We give a detailed account of the atom cloud size and temperature for both bosonic ((200)Hg and (202)Hg) and fermionic ((199)Hg and (201)Hg) isotopes. The bosonic isotope temperatures are in close agreement with Doppler cooling theory, while temperatures obtained for the fermionic isotopes are lower, suggesting the presence of sub-Doppler cooling.

Echelle spectrograph calibration with a frequency comb based on a harmonically mode-locked fiber laser: a proposal.

Details for constructing an astronomical frequency comb suitable as a wavelength reference for échelle spectrographs associated with optical telescopes are outlined. The source laser for the frequency comb is a harmonically mode-locked fiber laser with a central wavelength of 1.56 microm.

Efficient continuous-wave ultraviolet generation in LiB3O5 and RbD2AsO4.

We have demonstrated two continuous-wave nonlinear processes: third-harmonic generation (THG) of 1064-nm radiation with a lithium triborate (LBO) crystal, and second-harmonic generation of 696-nm radiation in deuterated rubidium dihydrogen arsenate. With 34 mW of 1064-nm and 25 mW of 532-nm radiation incident upon the LBO crystal, as much as 60 nW of third-harmonic power has been produced. We present the characteristics that optimize the production of nonlinear power in this sum-frequency generation process.

A passively mode-locked fiber laser at 1.54 mum with a fundamental repetition frequency reaching 2 GHz.

We demonstrate a fundamentally mode-locked fiber laser with a repetition frequency in excess of 2 GHz at a central wavelength of 1.535 mum. Co-doped ytterbium-erbium fiber provides the gain medium for the laser, affording high gain per unit length, while a semiconductor saturable absorber mirror (SAM) provides the pulse shaping mechanism in a standing wave cavity.

Considerations on the measurement of the stability of oscillators with frequency counters.

The most common time-domain measure frequency stability, the Allan variance, is typically estimated using a frequency counter. Close examination the operation of modern high-resolution frequency counters shows that they do not make measurements in the commonly assumed. The consequence is that the results typically reported by many laboratories using these counters are not, in fact, the Allan variance, but a distorted representation.

Noise properties of microwave signals synthesized with femtosecond lasers.

We discuss various aspects of high resolution measurements of phase fluctuations at microwave frequencies. This includes methods to achieve thermal noise limited sensitivity, along with the improved immunity to oscillator amplitude noise. A few prototype measurement systems were developed to measure phase fluctuations of microwave signals extracted from the optical pulse trains generated by femtosecond lasers.

Fiber-laser frequency combs with subhertz relative linewidths.

We investigate the comb linewidths of self-referenced, fiber-laser-based frequency combs by measuring the heterodyne beat signal between two independent frequency combs that are phase locked to a common cw optical reference. We demonstrate that the optical comb lines can exhibit instrument-limited, subhertz relative linewidths across the comb spectra from 1200 to 1720 nm with a residual integrated optical phase jitter of approximately 1 rad in a 60 mHz to 500 kHz bandwidth. The projected relative pulse timing jitter is approximately 1 fs.

Elimination of pump-induced frequency jitter on fiber-laser frequency combs.

Optical frequency combs generated by femtosecond fiber lasers typically exhibit significant frequency noise that causes broad optical linewidths, particularly in the comb wings and in the carrier-envelope offset frequency (f(ceo)) signal. We show these broad linewidths are mainly a result of white amplitude noise on the pump diode laser that leads to a breathing-like motion of the comb about a central fixed frequency. By a combination of passive noise reduction and active feedback using phase-lead compensation, this noise source is eliminated, thereby reducing the f(ceo) linewidth from 250 kHz to <1 Hz.

Optical frequency synthesis from a cryogenic microwave sapphire oscillator.

We demonstrate an optical frequency comb with fractional frequency instability of View Article and Find Full Text PDF

Mass transfer and flow in electrically charged micro- and nanochannels.

In this work, the fluid flow and mass transfer due to the presence of an electric field in a rectangular channel is examined. We consider a mixture of water or another neutral solvent and a salt compound, such as sodium chloride, for which the ionic species are entirely dissociated. Results are produced for the case in which the channel height is much greater than the electric double layer (EDL) (microchannel) and for the case in which the channel height is of the order of the width of the EDL (nanochannel).

Avian adenoviruses.

Adenovirus infections are ubiquitous in commercially farmed birds, and probably in all avian species. There is a wide range of virulence, in some cases even within the same serotype. While many infections are subclinical and appear to be of little economic or welfare importance, significant outbreaks of disease associated with adenovirus do occur.

Studies on a new enterovirus-like virus isolated from chickens.

During investigations into an outbreak of respiratory distress in broilers chicks, a small round virus was isolated following inoculation into chicken embryos. The isolate, designated 612, was identified as an enterovirus-like virus on the basis of its size and morphology, resistance to chloroform and to treatment at pH 3.0, and intracytoplasmic replication in cell culture.