Cosmology intertwined: A review of the particle physics, astrophysics, and cosmology associated with the cosmological tensions and anomalies

The standard Cold Dark Matter (CDM) cosmological model provides a good description of a wide range of astrophysical and cosmological data. However, there are a few big open questions that make the standard model look like an approximation to a more realistic scenario yet to be found. In this paper, we list a few important goals that need to be addressed in the next decade, taking into account the current discordances between the different cosmological probes, such as the disagreement in the value of the Hubble constant H0, the σ8–S8 tension, and other less statistically significant anomalies. While these discordances can still be in part the result of systematic errors, their persistence after several years of accurate analysis strongly hints at cracks in the standard cosmological scenario and the necessity for new physics or generalisations beyond the standard model. In this paper, we focus on the 5.0 σ tension between the Planck CMB estimate of the Hubble constant H0 and the SH0ES collaboration measurements. After showing the H0 evaluations made from different teams using different methods and geometric calibrations, we list a few interesting new physics models that could alleviate this tension and discuss how the next decade’s experiments will be crucial. Moreover, we focus on the tension of the Planck CMB data with weak lensing measurements and redshift surveys, about the value of the matter energy density m, and the amplitude or rate of the growth of structure (σ8, f σ8). We list a few interesting models proposed for alleviating this tension, and we discuss the importance of trying to fit a full array of data with a single model and not just one parameter at a time. Additionally, we present a wide range of other less discussed anomalies at a statistical significance level lower than the H0–S8 tensions which may also constitute hints towards new physics, and we discuss possible generic theoretical approaches that can collectively explain the non-standard nature of these signals. Finally, we give an overview of upgraded experiments and next-generation space missions and facilities on Earth that will be of crucial importance to address all these open questions

Evaluation of appendicitis risk prediction models in adults with suspected appendicitis

Background Appendicitis is the most common general surgical emergency worldwide, but its diagnosis remains challenging. The aim of this study was to determine whether existing risk prediction models can reliably identify patients presenting to hospital in the UK with acute right iliac fossa (RIF) pain who are at low risk of appendicitis. Methods A systematic search was completed to identify all existing appendicitis risk prediction models. Models were validated using UK data from an international prospective cohort study that captured consecutive patients aged 16–45 years presenting to hospital with acute RIF in March to June 2017. The main outcome was best achievable model specificity (proportion of patients who did not have appendicitis correctly classified as low risk) whilst maintaining a failure rate below 5 per cent (proportion of patients identified as low risk who actually had appendicitis). Results Some 5345 patients across 154 UK hospitals were identified, of which two‐thirds (3613 of 5345, 67·6 per cent) were women. Women were more than twice as likely to undergo surgery with removal of a histologically normal appendix (272 of 964, 28·2 per cent) than men (120 of 993, 12·1 per cent) (relative risk 2·33, 95 per cent c.i. 1·92 to 2·84; P < 0·001). Of 15 validated risk prediction models, the Adult Appendicitis Score performed best (cut‐off score 8 or less, specificity 63·1 per cent, failure rate 3·7 per cent). The Appendicitis Inflammatory Response Score performed best for men (cut‐off score 2 or less, specificity 24·7 per cent, failure rate 2·4 per cent). Conclusion Women in the UK had a disproportionate risk of admission without surgical intervention and had high rates of normal appendicectomy. Risk prediction models to support shared decision‐making by identifying adults in the UK at low risk of appendicitis were identified

Ramucirumab in patients with previously treated advanced hepatocellular carcinoma: Impact of liver disease aetiology.

BACKGROUND & AIMS Hepatocellular carcinoma (HCC) is a common complication of chronic liver disease with diverse underlying aetiologies. REACH/REACH-2 were global phase III studies investigating ramucirumab in advanced HCC (aHCC) following sorafenib treatment. We performed an exploratory analysis of outcomes by liver disease aetiology and baseline serum viral load. METHODS Meta-analysis was conducted in patients with aHCC and alpha-fetoprotein (AFP) ≥400 ng/mL (N = 542) from REACH/REACH-2 trials. Individual patient-level data were pooled with results reported by aetiology subgroup (hepatitis B [HBV] or C [HCV] and Other). Pre-treatment serum HBV DNA and HCV RNA were quantified using Roche COBAS AmpliPrep/COBAS TaqMan. Overall survival (OS) and progression-free survival (PFS) were evaluated using the Kaplan-Meier method and Cox proportional hazard model (stratified by study). RESULTS Baseline characteristics were generally balanced between arms in each subgroup (HBV: N = 225, HCV: N = 127, Other: N = 190). No significant difference in treatment effect by aetiology subgroup was detected (OS interaction P-value = .23). Median OS (ramucirumab vs placebo) in months was 7.7 versus 4.5 (HR 0.74, 95% CI 0.55-0.99) for HBV, 8.2 versus 5.5 (HR 0.82, 95% CI 0.55-1.23) for HCV and 8.5 versus 5.4 (HR 0.56, 95% CI 0.40-0.79) for Other. Ramucirumab showed similar overall safety profiles across subgroups. Worst outcomes were noted in patients with a detectable HBV load. Use of HBV antiviral therapy, irrespective of viral load, was beneficial for survival, liver function and liver-specific adverse events. CONCLUSIONS Ramucirumab improved survival across aetiology subgroups with a tolerable safety profile, supporting its use in patients with aHCC and elevated AFP

Electrical Control of Uniformity in Quantum Dot Devices

Highly uniform quantum systems are essential for the practical implementation of scalable quantum processors. While quantum dot spin qubits based on semiconductor technology are a promising platform for large-scale quantum computing, their small size makes them particularly sensitive to their local environment. Here, we present a method to electrically obtain a high degree of uniformity in the intrinsic potential landscape using hysteretic shifts of the gate voltage characteristics. We demonstrate the tuning of pinch-off voltages in quantum dot devices over hundreds of millivolts that then remain stable at least for hours. Applying our method, we homogenize the pinch-off voltages of the plunger gates in a linear array for four quantum dots, reducing the spread in pinch-off voltages by one order of magnitude. This work provides a new tool for the tuning of quantum dot devices and offers new perspectives for the implementation of scalable spin qubit arrays.</p

Data underlying the paper: Stable quantum dots in an InSb two-dimensional electron gas

Data for "Stable quantum dots in an InSb two-dimensional electron gas