Fate of charge order in overdoped La-based cuprates

In high-temperature cuprate superconductors, stripe order refers broadly to a coupled spin and charge modulation with a commensuration of eight and four lattice units, respectively. How this stripe order evolves across optimal doping remains a controversial question. Here we present a systematic resonant inelastic x-ray scattering study of weak charge correlations in La2-xSrxCuO4 and La1.8-xEu0.2SrxCuO4. Ultra high energy resolution experiments demonstrate the importance of the separation of inelastic and elastic scattering processes. Long-range temperature-dependent stripe order is only found below optimal doping. At higher doping, short-range temperature-independent correlations are present up to the highest doping measured. This transformation is distinct from and preempts the pseudogap critical doping. We argue that the doping and temperature-independent short-range correlations originate from unresolved electron-phonon coupling that broadly peaks at the stripe ordering vector. In La2-xSrxCuO4, long-range static stripe order vanishes around optimal doping and we discuss both quantum critical and crossover scenarios.

In situ uniaxial pressure cell for x-ray and neutron scattering experiments

We present an in situ uniaxial pressure device optimized for small angle x-ray and neutron scattering experiments at low-temperatures and high magnetic fields. A stepper motor generates force, which is transmitted to the sample via a rod with an integrated transducer that continuously monitors the force. The device has been designed to generate forces up to 200 N in both compressive and tensile configurations, and a feedback control allows operating the system in a continuous-pressure mode as the temperature is changed. The uniaxial pressure device can be used for various instruments and multiple cryostats through simple and exchangeable adapters. It is compatible with multiple sample holders, which can be easily changed depending on the sample properties and the desired experiment and allow rapid sample changes.

Constraints on Heavy Decaying Dark Matter from 570 Days of LHAASO Observations

The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 10^{5} and 10^{9}  GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.

Intraarticular steroids as DMARD-sparing agents for juvenile idiopathic arthritis flares: Analysis of the Childhood Arthritis and Rheumatology Research Alliance Registry

BACKGROUND

Children with juvenile idiopathic arthritis (JIA) who achieve a drug free remission often experience a flare of their disease requiring either intraarticular steroids (IAS) or systemic treatment with disease modifying anti-rheumatic drugs (DMARDs). IAS offer an opportunity to recapture disease control and avoid exposure to side effects from systemic immunosuppression. We examined a cohort of patients treated with IAS after drug free remission and report the probability of restarting systemic treatment within 12 months.

METHODS

We analyzed a cohort of patients from the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry who received IAS for a flare after a period of drug free remission. Historical factors and clinical characteristics and of the patients including data obtained at the time of treatment were analyzed.

RESULTS

We identified 46 patients who met the inclusion criteria. Of those with follow up data available 49% had restarted systemic treatment 6 months after IAS injection and 70% had restarted systemic treatment at 12 months. The proportion of patients with prior use of a biologic DMARD was the only factor that differed between patients who restarted systemic treatment those who did not, both at 6 months (79% vs 35%, p < 0.01) and 12 months (81% vs 33%, p < 0.05).

CONCLUSION

While IAS are an option for all patients who flare after drug free remission, it may not prevent the need to restart systemic treatment. Prior use of a biologic DMARD may predict lack of success for IAS. Those who previously received methotrexate only, on the other hand, are excellent candidates for IAS.

OS10.6.A What is the initial cell in the subventricular zone for human glioblastoma genesis?

Background

We all have a fundamental question about why glioblastoma (GBM) develops. In order to find the answer to this fundamental question, if you find out what the first cell is, you will get closer to the answer. GBM arises from the subventricular zone (SVZ). GBM is one of the most devastating tumour of human brain as the most optimal treatment barely prolongs the survival, and it does not cure the disease. As the majority of GBM tissues show copy number variations (CNV) of co-altered chromosomal 7 gain and 10 loss, we hypothesized the origin cell (Oc) of SVZ may be traced back with these markers. The cellular identity of the Oc is still unknown and it is different from the tumour-derived progenitor-like cells. We aimed to define these cells from the SVZ that have a potential to get activated into GBM.

Material and Methods

We compared bulk RNA sequencing (RNAseq) data of IDHwt GBM tumor tissue (n=122), tumor free SVZ from GBM patients (n=40), tumor-free control SVZ of non-glial tumor (n=9). Pared single nucleus RNAseq (snRNAseq) or single cell RNAseq (scRNAseq) samples of tumor free SVZ (n=11) and GBM tumor (n=8), were done to see cell specific CNVs. We developed genetically engineered mouse models for GBM genesis introducing three driver mutations (TP53, PTEN, and EGFRviii) into SVZ to isolate mouse Oc (mOc) and mouse cancer cells (mCc). The biological characteristics of separated mOc and mCc were compared. Bulk RNAseq and scRNAseq were performed on these cells (mOc, mCc), and their cellular state was compared with the human gene set.

Results

In this work, we found two types of the Oc in the RNA sequencing of 60 human tumour free-SVZ samples. Furthermore, single-cell level analysis revealed that two Oc types in SVZ harbor ongoing patterns of CNV co-alterations from Oc1 to Oc2, and finally to GBM. The Oc1 type cells contained the CNV signature of Oc2 ancestor with neural progenitor cell (NPC) signature. Oc2 type cells expressed a high level of EGFR than other cells with astrocyte-like cell signature. Both of these cells expressed oligodendrocyte progenitor cell (OPC)-like signatures in the SVZ. We validated the human-based findings by using the P53/PTEN/EGFR-mutant mouse model with EGFR/tdTomato overexpression and P53/PTEN knockout in the SVZ cells. As a result, non-tumourigenic and highly motile Oc-like cell-states are found in the mouse models, supporting the firework-like migration pattern from the SVZ.

Conclusion

Our results demonstrate how members of Oc preoccupy the SVZ, known as the stem cell niche and give rise to the tumour. We anticipate that a new therapy may emerge by targeting the Oc in the SVZ.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Evidence for a Square-Square Vortex Lattice Transition in a High-T_{c} Cuprate Superconductor

Using sound velocity and attenuation measurements in high magnetic fields, we identify a new transition in the vortex lattice state of La_{2-x}Sr_{x}CuO_{4}. The transition, observed in magnetic fields exceeding 35 T and temperatures far below zero field T_{c}, is detected in the compression modulus of the vortex lattice, at a doping level of x=p=0.17. Our theoretical analysis based on Eilenberger's theory of the vortex lattice shows that the transition corresponds to the long-sought 45° rotation of the square vortex lattice, predicted to occur in d-wave superconductors near a van Hove singularity.