Measurements of neutrino oscillation parameters from the T2K experiment using 3.6×1021 protons on target

The T2K experiment presents new measurements of neutrino oscillation parameters using 19.7 ( 16.3 ) × 10 20 protons on target (POT) in (anti-)neutrino mode at the far detector (FD). Compared to the previous analysis, an additional 4.7 × 10 20 POT neutrino data was collected at the FD. Significant improvements were made to the analysis methodology, with the near-detector analysis introducing new selections and using more than double the data. Additionally, this is the first T2K oscillation analysis to use NA61/SHINE data on a replica of the T2K target to tune the neutrino flux model, and the neutrino interaction model was improved to include new nuclear effects and calculations. Frequentist and Bayesian analyses are presented, including results on sin 2 θ 13 and the impact of priors on the δ CP measurement. Both analyses prefer the normal mass ordering and upper octant of sin 2 θ 23 with a nearly maximally CP-violating phase. Assuming the normal ordering and using the constraint on sin 2 θ 13 from reactors, sin 2 θ 23 = 0 . 561 - 0.032 + 0.021 using Feldman-Cousins corrected intervals, and Δ m 32 2 = 2 . 494 - 0.058 + 0.041 × 10 - 3 eV 2 using constant Δ χ 2 intervals. The CP-violating phase is constrained to δ CP = - 1 . 97 - 0.70 + 0.97 using Feldman-Cousins corrected intervals, and δ CP = 0 , π is excluded at more than 90% confidence level. A Jarlskog invariant of zero is excluded at more than 2 σ credible level using a flat prior in δ CP , and just below 2 σ using a flat prior in sin δ CP . When the external constraint on sin 2 θ 13 is removed, sin 2 θ 13 = 28 . 0 - 6.5 + 2.8 × 10 - 3 , in agreement with measurements from reactor experiments. These results are consistent with previous T2K analyses.

Scintillation light detection in the 6-m drift-length ProtoDUNE Dual Phase liquid argon TPC

DUNE is a dual-site experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and nucleon decay searches. ProtoDUNE Dual Phase (DP) is a 6  ×  6  ×  6 m 3 liquid argon time-projection-chamber (LArTPC) that recorded cosmic-muon data at the CERN Neutrino Platform in 2019-2020 as a prototype of the DUNE Far Detector. Charged particles propagating through the LArTPC produce ionization and scintillation light. The scintillation light signal in these detectors can provide the trigger for non-beam events. In addition, it adds precise timing capabilities and improves the calorimetry measurements. In ProtoDUNE-DP, scintillation and electroluminescence light produced by cosmic muons in the LArTPC is collected by photomultiplier tubes placed up to 7 m away from the ionizing track. In this paper, the ProtoDUNE-DP photon detection system performance is evaluated with a particular focus on the different wavelength shifters, such as PEN and TPB, and the use of Xe-doped LAr, considering its future use in giant LArTPCs. The scintillation light production and propagation processes are analyzed and a comparison of simulation to data is performed, improving understanding of the liquid argon properties.

The role of laparoscopic adrenalectomy for adrenal tumours of 6 cm or greater

BACKGROUND

Laparoscopic adrenalectomy (LA) has been shown to reduce hospital stay and morbidity when compared to open adrenalectomy (OA). It is uncertain if the laparoscopic resection of large (>/=6 cm) potentially malignant adrenal tumours is appropriate due to concern over incomplete resection and local recurrence. The aim of the present study was to compare the outcomes of LA for tumours >/=6 cm with those < 6 cm.

METHODS

Details of all patients referred with adrenal tumours between January 1999 and January 2006 had been recorded prospectively on a database. LA was performed using a lateral transabdominal approach. Contraindications to LA were local invasion requiring en bloc resection of adjacent organs or the requirement of additional open procedures.

RESULTS

103 patients were referred for adrenal resection. Three with metastatic adrenal carcinoma and two with severe cardiorespiratory disease were deemed unsuitable for operation. One hundred and eleven adrenalectomies were performed: 101 LAs and 10 OAs. Thirty-nine LA were for tumours >/=6 cm while nine OA were for tumours >/=6 cm. There were no significant differences between the median total anaesthetic time, postoperative complications or postoperative stay for patients undergoing LA for tumours >/=6 cm versus tumours <6 cm. Of the six conversions, five were performed for adrenal tumours >/=6 cm [local invasion (n = 3), adhesions (n = 1), primary renal carcinoma (n = 1)]. All tumours in the LA group were resected with clear margins and at a median follow up of 50 months (range 38-74 months). There has been no evidence of local recurrence.

CONCLUSIONS

In the absence of local invasion, the outcomes of laparoscopic adrenalectomy for patients with tumours >/=6 cm were comparable to those with tumours <6 cm. This has helped confirm a policy of initial laparoscopic resection for all noninvasive adrenal tumours can be applied safely.

Cloning and expression of the Haemophilus influenzae transferrin receptor genes

The genomic transferrin receptor genes (tbpA and tbpB) from two strains of Haemophilus influenzae type b (Hib) and two strains of non-typable H. influenzae (NTHi) have been cloned and sequenced. The deduced protein sequences of the H. influenzae tbpA genes were 95-100% conserved and those of the tbpB genes were 66-100% conserved. The tbpB gene from one strain of NTHi was found to encode a truncated Tbp2 protein. The tbpB genes from four additional NTHi strains were amplified by the polymerase chain reaction (PCR) utilizing primers derived from the conserved N-terminal sequences of Tbp1 and Tbp2 and were found to encode full-length proteins. Although several bacterial species express transferrin receptors, when the Tbp1 and Tbp2 sequences from different organisms were compared, there was only limited homology. Recombinant Tbp1 and Tbp2 proteins were expressed from Escherichia coli and antisera were raised to the purified proteins. There was significant antigenic conservation of both Tbp1 and Tbp2 amongst H. influenzae strains, as determined by Western blot analysis. In a passive model of bacteraemia, infant rats were protected from challenge with Hib after transfer of anti-rTbp2 antiserum, but not after anti-rTbp1 antiserum.

Hybrid genes over-express pertactin from Bordetella pertussis

Pertactin is a surface adhesin of Bordetella pertussis which is produced in small quantities when expressed from the native prn promoter. Hybrid genes were constructed in which the prn promoter was replaced by either the fha or tox promoter. Recombinant B. pertussis strains containing chromosomally integrated hybrid tox promoter/prn (toxpprn) or fha promoter/prn (fhapprn) genes expressed pertactin at approximately 5- and 8-fold the wild-type level, respectively. The pertactin was correctly processed and secreted and was biochemically and antigenically comparable to its wild-type counterpart, as determined by N-terminal sequence analysis, immunoblotting, peptide mapping, circular dichroism and antigenicity studies. In an adherence assay, a strain over-expressing pertactin was no more adherent than the wild-type strain, but a pertactin-deficient strain was less adherent.