Since the initial data taking of the CERN LHC, the CMS experiment has undergone substantial upgrades and improvements. This paper discusses the CMS detector as it is configured for the third data-taking period of the CERN LHC, Run 3, which started in 2022. The entire silicon pixel tracking detector was replaced. A new powering system for the superconducting solenoid was installed. The electronics of the hadron calorimeter was upgraded. All the muon electronic systems were upgraded, and new muon detector stations were added, including a gas electron multiplier detector. The precision proton spectrometer was upgraded. The dedicated luminosity detectors and the beam loss monitor were refurbished. Substantial improvements to the trigger, data acquisition, software, and computing systems were also implemented, including a new hybrid CPU/GPU farm for the high-level trigger.

This paper describes the Combine software package used for statistical analyses by the CMS Collaboration. The package, originally designed to perform searches for a Higgs boson and the combined analysis of those searches, has evolved to become the statistical analysis tool presently used in the majority of measurements and searches performed by the CMS Collaboration. It is not specific to the CMS experiment, and this paper is intended to serve as a reference for users outside of the CMS Collaboration, providing an outline of the most salient features and capabilities. Readers are provided with the possibility to run Combine and reproduce examples provided in this paper using a publicly available container image. Since the package is constantly evolving to meet the demands of ever-increasing data sets and analysis sophistication, this paper cannot cover all details of Combine. However, the online documentation referenced within this paper provides an up-to-date and complete user guide.

Background. The aim of this study was to investigate pathologic differences of the placenta in pregnancies complicated by gestational diabetes compared to non‐diabetic pregnancies. Methods. Forty singleton pregnancies complicated by gestational diabetes were recruited and compared to 40 consecutive normal pregnancies. A pathologist, blinded to all clinical data, reviewed all histological samples of the placentas. The histological assessment was carried out with regard to the following aspects: fetal vessel thrombosis, villous immaturity, chorangiosis, presence of nucleated fetal red blood cells (NFRBCs), ischemia, infarction, presence of hydropic or avascular villi, lymphohistiocytic villitis and villous fibrinoid necrosis. Results. The presence of degenerative lesions such as fibrinoid necrosis and vascular lesions like chorangiosis was apparent, mainly in the diabetes group. Villous immaturity and the presence of NFRBC as an indication of chronic fetal hypoxia were significantly increased in the placentas of women with diabetes compared with the control group. Fetal/placental weight ratio was significantly lower in the diabetic group. Conclusion. Histological abnormalities were observed more frequently in the diabetic placentas compared to the controls. These findings support the hypothesis that impaired placental function is one of the main reasons for the increased frequency of fetal complications in diabetic pregnancies.

To evaluate the efficacy of emergency cerclage in cases with dilated cervix and protruding fetal membranes in a group of women considered at low risk for preterm delivery by their obstetric histories. All cases of cervical dilatation and bulging membranes were detected through a transvaginal ultrasonographic screening for preterm delivery between 18 and 26 weeks during a 6-year study period. Twenty-nine women underwent an emergency cervical cerclage and composed the cerclage group, whereas 17 others refused and formed the bed rest group. All patients were given antibiotics and prophylactic tocolysis. The mean prolongation of pregnancy (8.8 weeks) and the mean birth weight (2,101 g) after cerclage placement differed significantly from those of the bed rest group (3.1 weeks and 739 g, respectively). Twenty-five of the 29 pregnancies in the cerclage group ended in live birth, compared with 7 of the 17 pregnancies in the bed rest group (P = .001) (relative risk [RR] 0.33, 95% confidence interval [CI] 0.11-0.98). Neonatal survival was 96% in the cerclage group and 57.1% in the bed rest group (P = .025) (RR 0.09, 95% CI 0.01-0.76). The preterm delivery rate less than 32 weeks was 31% and 94.1% in the cerclage and the bed rest groups, respectively (P < .001) (RR 0.33, 95% CI 0.19-0.57), whereas the admission to neonatal intensive care unit was 28% and 85.7% in the 2 groups, respectively, (P = .01) (RR 0.33, 95% CI 0.16-0.66). Emergency cervical cerclage can be accomplished safely in women with dilated cervix and bulging membranes. It can reduce preterm delivery before 32 weeks and improve neonatal survival compared with bed rest. II-1.

The CERN LHC provided proton and heavy ion collisions during its Run 2 operation period from 2015 to 2018. Proton-proton collisions reached a peak instantaneous luminosity of 2.1× 10³⁴ cm^-2s^-1, twice the initial design value, at √(s)=13 TeV. The CMS experiment records a subset of the collisions for further processing as part of its online selection of data for physics analyses, using a two-level trigger system: the Level-1 trigger, implemented in custom-designed electronics, and the high-level trigger, a streamlined version of the offline reconstruction software running on a large computer farm. This paper presents the performance of the CMS high-level trigger system during LHC Run 2 for physics objects, such as leptons, jets, and missing transverse momentum, which meet the broad needs of the CMS physics program and the challenge of the evolving LHC and detector conditions. Sophisticated algorithms that were originally used in offline reconstruction were deployed online. Highlights include a machine-learning b tagging algorithm and a reconstruction algorithm for tau leptons that decay hadronically.