High-precision measurement of the W boson mass with the CDF II detector

The mass of the W boson, a mediator of the weak force between elementary particles, is tightly constrained by the symmetries of the standard model of particle physics. The Higgs boson was the last missing component of the model. After observation of the Higgs boson, a measurement of the W boson mass provides a stringent test of the model. We measure the W boson mass, M_W, using data corresponding to 8.8 inverse femtobarns of integrated luminosity collected in proton-antiproton collisions at a 1.96 tera-electron volt center-of-mass energy with the CDF II detector at the Fermilab Tevatron collider. A sample of approximately 4 million W boson candidates is used to obtain [Formula: see text], the precision of which exceeds that of all previous measurements combined (stat, statistical uncertainty; syst, systematic uncertainty; MeV, mega-electron volts; c, speed of light in a vacuum). This measurement is in significant tension with the standard model expectation.

The association between low skeletal muscle mass and delirium: results from the nationwide multi-centre Italian Delirium Day 2017

Introduction

Delirium and sarcopenia are common, although underdiagnosed, geriatric syndromes. Several pathological mechanisms can link delirium and low skeletal muscle mass, but few studies have investigated their association. We aimed to investigate (1) the association between delirium and low skeletal muscle mass and (2) the possible role of calf circumference mass in finding cases with delirium.

Methods

The analyses were conducted employing the cross-sectional “Delirium Day” initiative, on patient 65 years and older admitted to acute hospital medical wards, emergency departments, rehabilitation wards, nursing homes and hospices in Italy in 2017. Delirium was diagnosed as a 4 + score at the 4-AT scale. Low skeletal muscle mass was operationally defined as calf circumference ≤ 34 cm in males and ≤ 33 cm in females. Logistic regression models were used to investigate the association between low skeletal muscle mass and delirium. The discriminative ability of calf circumference was evaluated using non-parametric ROC analyses.

Results

A sample of 1675 patients was analyzed. In total, 73.6% of participants had low skeletal muscle mass and 24.1% exhibited delirium. Low skeletal muscle mass and delirium showed an independent association (OR: 1.50; 95% CI 1.09–2.08). In the subsample of patients without a diagnosis of dementia, the inclusion of calf circumference in a model based on age and sex significantly improved its discriminative accuracy [area under the curve (AUC) 0.69 vs 0.57, p < 0.001].

Discussion and conclusion

Low muscle mass is independently associated with delirium. In patients without a previous diagnosis of dementia, calf circumference may help to better identify those who develop delirium.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40520-021-01950-8.

Percutaneous puncture during PCNL: new perspective for the future with virtual imaging guidance

CONTEXT

Large and complex renal stones are usually treated with percutaneous nephrolithotomy (PCNL). One of the crucial steps in this procedure is the access to the collecting system with the percutaneous puncture and this maneuver leads to a risk of vascular and neighboring organs' injury. In the last years, the application of virtual image-guided surgery has gained wide diffusion even in this specific field.

OBJECTIVES

To provide a short overview of the most recent evidence on current applications of virtual imaging guidance for PCNL.

EVIDENCE ACQUISITION

A non-systematic review of the literature was performed. Medline, PubMed, the Cochrane Database and Embase were screened for studies regarding the use virtual imaging guidance for PCNL.

EVIDENCE SYNTHESIS

3D virtual navigation technology for PCNL was first used in urology with the purpose of surgical training and surgical planning; subsequently, the field of surgical navigation with different modalities (from cognitive to augmented reality or mixed reality) had been explored. Finally, anecdotal preliminary experiences explored the potential application of artificial intelligence guidance for percutaneous puncture.

CONCLUSION

Nowadays, many experiences proved the potential benefit of virtual guidance for surgical simulation and training. Focusing on surgery, this tool revealed to be useful both for surgical planning, allowed to achieve a better surgical performance, and for surgical navigation by using augmented reality and mixed reality systems aimed to assist the surgeon in real time during the intervention.