Observation of molecules produced from a Bose-Einstein condensate

Molecules are created from a Bose-Einstein condensate of atomic 87Rb using a Feshbach resonance. A Stern-Gerlach field is applied, in order to spatially separate the molecules from the remaining atoms. For detection, the molecules are converted back into atoms, again using the Feshbach resonance. The measured position of the molecules yields their magnetic moment. This quantity strongly depends on the magnetic field, thus revealing an avoided crossing of two bound states at a field value slightly below the Feshbach resonance. This avoided crossing is exploited to trap the molecules in one dimension.Comment: 4 pages, 4 figures, minor revison

Feshbach Spectroscopy of a Shape Resonance

We present a new spectroscopy technique for studying cold-collision properties. The technique is based on the association and dissociation of ultracold molecules using a magnetically tunable Feshbach resonance. The energy and lifetime of a shape resonance are determined from a measurement of the dissociation rate. Additional spectroscopic information is obtained from the observation of a spatial interference pattern between an outgoing s wave and d wave. The experimental data agree well with the results from a new model, in which the dissociation process is connected to a scattering gedanken experiment, which is analyzed using a coupled-channels calculation.Comment: Introduction rewritte

Dissociation of Feshbach Molecules into Different Partial Waves

Ultracold molecules can be associated from ultracold atoms by ramping the magnetic field through a Feshbach resonance. A reverse ramp dissociates the molecules. Under suitable conditions, more than one outgoing partial wave can be populated. A theoretical model for this process is discussed here in detail. The model reveals the connection between the dissociation and the theory of multichannel scattering resonances. In particular, the decay rate, the branching ratio, and the relative phase between the partial waves can be predicted from theory or extracted from experiment. The results are applicable to our recent experiment in 87Rb, which has a d-wave shape resonance.Comment: Added Refs.[32-38

Clinical Resistome Screening of 1,110 Escherichia coli Isolates Efficiently Recovers Diagnostically Relevant Antibiotic Resistance Biomarkers and Potential Novel Resistance Mechanisms

Multidrug-resistant pathogens represent one of the biggest global healthcare challenges. Molecular diagnostics can guide effective antibiotics therapy but relies on validated, predictive biomarkers. Here we present a novel, universally applicable workflow for rapid identification of antimicrobial resistance (AMR) biomarkers from clinical Escherichia coli isolates and quantitatively evaluate the potential to recover causal biomarkers for observed resistance phenotypes. For this, a metagenomic plasmid library from 1,110 clinical E. coli isolates was created and used for high-throughput screening to identify biomarker candidates against Tobramycin (TOB), Ciprofloxacin (CIP), and Trimethoprim Sulfamethoxazole (TMP-SMX). Identified candidates were further validated in vitro and also evaluated in silico for their diagnostic performance based on matched genotype phenotype data. AMR biomarkers recovered by the metagenomics screening approach mechanistically explained 77% of observed resistance phenotypes for Tobramycin, 76% for Trimethoprim-Sulfamethoxazole, and 20% Ciprofloxacin. Sensitivity for Ciprofloxacin resistance detection could be improved to 97% by complementing results with AMR biomarkers that are undiscoverable due to intrinsic limitations of the workflow. Additionally, when combined in a multiplex diagnostic in silico panel, the identified AMR biomarkers reached promising positive and negative predictive values of up to 97 and 99%, respectively. Finally, we demonstrate that the developed workflow can be used to identify potential novel resistance mechanisms

Experimental comparison of photon versus particle computed tomography to predict tissue relative stopping powers

Purpose: Measurements comparing relative stopping power (RSP) accuracy of state-of-the-art systems representing single-energy and dual-energy computed tomography (SECT/DECT) with proton CT (pCT) and helium CT (HeCT) in biological tissue samples. Methods: We used 16 porcine and bovine samples of various tissue types and water, covering an RSP range from 0.90urn:x-wiley:00942405:media:mp15283:mp15283-math-00010.06 to 1.78 urn:x-wiley:00942405:media:mp15283:mp15283-math-00020.05. Samples were packed and sealed into 3D-printed cylinders (urn:x-wiley:00942405:media:mp15283:mp15283-math-0003 cm, urn:x-wiley:00942405:media:mp15283:mp15283-math-0004 cm) and inserted into an in-house designed cylindrical polymethyl methacrylate (PMMA) phantom (urn:x-wiley:00942405:media:mp15283:mp15283-math-0005 cm, urn:x-wiley:00942405:media:mp15283:mp15283-math-0006 cm). We scanned the phantom in a commercial SECT and DECT (120 kV; 100 and 140 kV/Sn (tin-filtered)); and acquired pCT and HeCT (urn:x-wiley:00942405:media:mp15283:mp15283-math-0007 MeV/u, 2urn:x-wiley:00942405:media:mp15283:mp15283-math-0008 steps, urn:x-wiley:00942405:media:mp15283:mp15283-math-0009 (p)/urn:x-wiley:00942405:media:mp15283:mp15283-math-0010 (He) particles/projection) with a particle imaging prototype. RSP maps were calculated from SECT/DECT using stoichiometric methods and from pCT/HeCT using the DROP-TVS algorithm. We estimated the average RSP of each tissue per modality in cylindrical volumes of interest and compared it to ground truth RSP taken from peak-detection measurements. Results: Throughout all samples, we observe the following root-mean-squared RSP prediction errors urn:x-wiley:00942405:media:mp15283:mp15283-math-0011 combined uncertainty from reference measurement and imaging: SECT 3.10urn:x-wiley:00942405:media:mp15283:mp15283-math-00122.88%, DECT 0.75urn:x-wiley:00942405:media:mp15283:mp15283-math-00132.80%, pCT 1.19urn:x-wiley:00942405:media:mp15283:mp15283-math-0014 2.81%, and HeCT 0.78urn:x-wiley:00942405:media:mp15283:mp15283-math-00152.81%. The largest mean errors urn:x-wiley:00942405:media:mp15283:mp15283-math-0016 combined uncertainty per modality are SECT 8.22 urn:x-wiley:00942405:media:mp15283:mp15283-math-00172.79% in cortical bone, DECT 1.74urn:x-wiley:00942405:media:mp15283:mp15283-math-00182.00% in back fat, pCT 1.80 urn:x-wiley:00942405:media:mp15283:mp15283-math-00194.27% in bone marrow, and HeCT 1.37urn:x-wiley:00942405:media:mp15283:mp15283-math-00204.25% in bone marrow. Ring artifacts were observed in both pCT and HeCT reconstructions, imposing a systematic shift to predicted RSPs. Conclusion: Comparing state-of-the-art SECT/DECT technology and a pCT/HeCT prototype, DECT provided the most accurate RSP prediction, closely followed by particle imaging. The novel modalities pCT and HeCT have the potential to further improve on RSP accuracies with work focusing on the origin and correction of ring artifacts. Future work will study accuracy of proton treatment plans using RSP maps from investigated imaging modalities

Controlling a magnetic Feshbach resonance with laser light

The capability to tune the strength of the elastic interparticle interaction is crucial for many experiments with ultracold gases. Magnetic Feshbach resonances are a tool widely used for this purpose, but future experiments would benefit from additional flexibility such as spatial modulation of the interaction strength on short length scales. Optical Feshbach resonances offer this possibility in principle, but suffer from fast particle loss due to light-induced inelastic collisions. Here we show that light near-resonant with a molecular bound-to-bound transition can be used to shift the magnetic field at which a magnetic Feshbach resonance occurs. This makes it possible to tune the interaction strength with laser light and at the same time induce considerably less loss than an optical Feshbach resonance would do

Identification of the Tumor Infiltrating Lymphocytes (TILs) Landscape in Pure Squamous Cell Carcinoma of the Bladder

Simple Summary Treatment options in squamous cell carcinoma (SCC) of the bladder are limited and prognosis is poor. In this report we investigated the impact of tumor-infiltrating lymphocytes (TILs) in SCC of the bladder in patients undergoing radical cystectomy. We found that subsets of TILs hold predictive value for OS and PFS. We conclude that TILs might stratify patients with bladder SCC for immunotherapy. Background: Tumor infiltrating lymphocytes (TILs) are known as important prognostic biomarkers and build the fundament for immunotherapy. However, the presence of TILs and its impact on outcome in pure squamous cell carcinoma (SCC) of the bladder remains uncertain. Methods: Out of 1600 patients undergoing radical cystectomy, 61 patients revealed pure bladder SCC in the final histopathological specimen. Retrospectively, immunohistochemical staining was performed on a subset of TILs (CD3+, CD4+, CD8+, CD20+). Endpoints were overall survival (OS), cancer-specific survival (CSS) and progression-free survival (PFS). The Kaplan-Meier method was used to evaluate survival outcomes. Results: Strong infiltration of CD3+ was found in 27 (44%);of CD4+ in 28 (46%);of CD8+ in 26 (43%);and of CD20+ in 27 tumors (44%). Improved OS was observed for strong CD3+ (p < 0.001);CD4+ (p = 0.045);CD8+ (p = 0.001);and CD20+ infiltration (p < 0.001). Increased rates of PFS were observed for CD3+ (p = 0.025) and CD20+ TILs (p = 0.002). In multivariate analyses, strong CD3+ (HR: 0.163, CI: 0.044-0.614) and strong CD8+ TILs (HR: 0.265, CI: 0.081-0.864) were revealed as predictors for OS and the strong infiltration of CD20+ cells (HR: 0.095, CI: 0.019-0.464) for PFS. Conclusions: These first results of TILs in bladder SCC revealed predictive values of CD3+, CD8+ and CD20+