Motion of a Vector Particle in a Curved Spacetime. I. Lagrangian Approach

From the simple Lagrangian the equations of motion for the particle with spin are derived. The spin is shown to be conserved on the particle world-line. In the absence of a spin the equation coincides with that of a geodesic. The equations of motion are valid for massless particles as well, since mass does not enter the equations explicitely.Comment: 6 pages, uses mpla1.sty, published in MPLA, replaced with corrected typo

Breast Lesion Excision System in the diagnosis and treatment of intraductal papillomas - A feasibility study

Objectives: This study aims to evaluate the feasibility of Breast Lesion Excision System (BLES) in the treatment of intraductal papillomas. Material and methods: All patients with a needle biopsy-based suspicion of an intraductal papilloma who consequently underwent a BLES procedure at Helsinki University Hospital between 2011 and 2016 were included in this retrospective study. The purpose of the BLES procedure was either to excise the entire lesion or in few cases to achieve better sampling. Results: In total, 74 patients underwent 80 BLES procedures. Pathological diagnosis after the BLES biopsy confirmed an intraductal papilloma without atypia in 43 lesions, whereas 10 lesions were upgraded to high-risk lesions (HRL) with either atypical ductal hyperplasia or lobular carcinoma in situ. Five cases were upgraded to malignancy, two were invasive ductal carcinomas and three were ductal carcinoma in situ. Additionally, 18 lesions were diagnosed as other benign lesions. Four procedures failed. Complete excision with BLES was achieved in 19 out of 43 intraductal papillomas, 6 out of 10 HRL and two out of five malignant lesions. No major complications occurred. The BLES procedure was adequate in the management of the 71 breast lesions. Conclusion: The BLES procedure is an acceptable method for the management of small benign and high-risk breast lesions such as intraductal papillomas in selected patients. Thus, a great amount of diagnostic surgical biopsies can be avoided. (C) 2017 Elsevier Ltd, BASO similar to The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.Peer reviewe

Comparison of vacuum-assisted excision (VAE) and breast lesion excision system (BLES) in the treatment of intraductal papillomas

Purpose: This study aims to compare the feasibility of VAE and BLES in the treatment of intraductal papillomas. Material and methods: Patients with a suspected intraductal papilloma who underwent a BLES or a VAE procedure were included in this retrospective study. The BLES procedures were performed between November 2011 and June 2016 and the VAE procedures between May 2018 and September 2020 at the Department of Radiology of Helsinki University Hospital (HUH). The procedures were performed with an intent of complete removal of the lesions. Results: In total, 72 patients underwent 78 BLES procedures and 95 patients underwent 99 VAE procedures. Altogether 52 (60%) papillomas with or without atypia were completely removed with VAE, whereas 24 (46%) were completely removed with BLES, p = 0.115. The median radiological size of the high-risk lesions completely removed with BLES was 6 mm (4-12 mm), whereas with VAE it was 8 mm (3-22 mm), p = 0.016. Surgery was omitted in 90 (94.7%) non-malignant breast lesions treated with VAE and in 66 (90.4%) treated with BLES, p = 0.368. Conclusion: Both VAE and BLES were feasible in the treatment of intraductal papillomas. In most non-malignant lesions surgery was avoided, but VAE was feasible in larger lesions than BLES. However, follow-up ultrasound was needed more often after VAE. The histopathologic assessment is more reliable after BLES, as the lesion is removed as a single sample. (C) 2021 The Authors. Published by Elsevier Ltd.Peer reviewe

Superconducting microstrip detectors

Superconducting NbN microstrip counters feature radiation hardness two orders of magnitude higher than conventional Si strip detectors, spatial resolution limited only by lithographic techniques (0.1 - 2 microns), intrinsic signal rise time of 2 ps, and signal transport over large distances without losses. The aim of this proposal is to improve understanding of the physics of such detectors and to establish their large- scale feasibility

Resection margins and local recurrences in breast cancer : Comparison between conventional and oncoplastic breast conserving surgery

Background: This retrospective cohort study aims to compare surgical margins, reoperations and local recurrences after conventional or oncoplastic breast conservation surgery (BCS). Furthermore, we aim to investigate differences between various oncoplastic techniques. Material and methods: We reviewed 1800 consecutive patients with primary invasive breast cancer (N =1707) or ductal carcinoma in situ (N = 93) who underwent BCS at Helsinki University Hospital between 2010 and 2012. Results: Conventional BCS was performed in 1189 (66.1%) patients, oncoplastic BCS in 611 (33.9%). Various oncoplastic techniques were used. Patients with oncoplastic BCS had more often multifocal (p There was no difference, however, in surgical margins (p = 0.578) or reoperation rates (p = 0.430) between the groups. A total of 152 (8.4%) patients were reoperated because of insufficient margins, 96 (8.1%) in the conventional, 56 (9.2%) in the oncoplastic BCS group. The median follow-up time was 75 (2-94) months. There was no difference in local recurrence-free survival between the conventional and oncoplastic BCS groups (log-rank test, p = 0.172). Conclusions: Oncoplastic BCS was used for larger, multifocal and more aggressive tumours. Nevertheless, no difference in reoperation rate or local recurrences were found. Oncoplastic BCS is as safe as conventional BCS enabling breast conserving for patients who otherwise were candidates for mastectomy. (C) 2019 Elsevier Ltd, BASO - The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.Peer reviewe

Superconducting NbN microstrip detectors

Superconducting NbN strip transmission line counters and coupling circuits were processed on silicon wafers using thin film techniques, and they were characterized with several methods to verify the design principles. The stripline circuits, designed using microwave design rules, were simulated using a circuit design tool enhanced to include modelling of the superconducting lines. The strips, etched out of the 282 nm thick top NbN film with resistivity 284 µ?cm at 20 K, have critical temperatures in the range 12 to 13 K and a critical current density approximately Jc(0) = 3.3·105 A/cm2. The linearized heat transfer coefficient between the strip and the substrate is approximately 1.1·105 W/(m2K) and the healing length is about 1.6 µm between 3 and 5 K temperatures. Traversing 5 MeV a-particles caused the strips to quench. No events due to electrons could be detected in agreement with the predicted signal amplitude which is below the noise threshold of our wideband circuitry. The strip bias current and hence the signal amplitude were limited due to a microbridge at the isolator step of the impedance transformer

Resection margins and local recurrences of impalpable breast cancer : Comparison between radioguided occult lesion localization (ROLL) and radioactive seed localization (RSL)

Objectives: The aim of this retrospective study is to compare surgical margins, reoperation rates and local recurrences after breast conserving surgery (BCS) using radioguided occult lesion localization (ROLL) or radioactive seed localization (RSL). Materials and methods: We reviewed 744 consecutive patients with impalpable primary invasive breast cancer who underwent BCS at Helsinki University Hospital between 2010 and 2012. ROLL was used in our unit until October 31st, 2011; from November 1st we changed localization method to RSL. Results: 318 patients underwent ROLL and 426 RSL. Patients in the RSL group had more often multifocal (p = 0.013) tumours. No statistically significant differences were found regarding tumour size, specimen weight, histology or grade of tumours or lymph node status. 42 (5.6%) patients were reoperated because of insufficient margins, 13 (4.1%) in the ROLL group and 29 (6.8%) in the RSL group. The reoperation rate was not different between the groups either in the univariable analysis (p = 0.112) or in the multivariable binary logistic regression analysis (p = 0.204). Risk factors for reoperations were multifocality of the tumour (p Conclusion: Reoperation rates and LRFS were comparable for ROLL and RSL in patients with impalpable breast cancer treated with BCS. (C) 2019 Elsevier Ltd. All rights reserved.Peer reviewe

Sterile Neutrinos, Coherent Scattering and Oscillometry Measurements with Low-temperature Bolometers

Coherent neutrino-nucleon scattering offers a unique approach in the search for physics beyond the Standard Model. When used in conjunction with mono-energetic neutrino sources, the technique can be sensitive to the existence of light sterile neutrinos. The ability to utilize such reactions has been limited in the past due to the extremely low energy threshold (10-50 eV) needed for detection. In this paper, we discuss an optimization of cryogenic solid state bolometers that enables reaching extremely low kinetic energy thresholds. We investigate the sensitivity of an array of such detectors to neutrino oscillations to sterile states. A recent analysis of available reactor data appears to favor the existence of such such a sterile neutrino with a mass splitting of $|\Delta m_{\rm sterile}|^2 \ge 1.5$ eV$^2$ and mixing strength of $\sin^2{2\theta_{\rm sterile}} = 0.17\pm 0.08$ at 95% C.L. An array of such low-threshold detectors would be able to make a definitive statement as to the validity of the interpretation.Comment: 14 pages, 10 figures. Version 2: Temperature dependence on alpha fixed from earlier versio

Hyperglycemia and lower diet quality in pregnant overweight women and increased infant size at birth and at 13 months of age - STEPS study

Conclusions: Maternal prepregnancy overweight increases risk of hyperglycemia in late-pregnancy and increased infant size at birth and 13 months possibly predisposing the infant to health risks later in life. (C) 2013 Elsevier Ireland Ltd. All rights reserved.</p

Equations of Motion of Spinning Relativistic Particle in External Fields

We consider the motion of a spinning relativistic particle in external electromagnetic and gravitational fields, to first order in the external field, but to an arbitrary order in spin. The correct account for the spin influence on the particle trajectory is obtained with the noncovariant description of spin. Concrete calculations are performed up to second order in spin included. A simple derivation is presented for the gravitational spin-orbit and spin-spin interactions of a relativistic particle. We discuss the gravimagnetic moment (GM), a specific spin effect in general relativity. It is demonstrated that for the Kerr black hole the gravimagnetic ratio, i.e., the coefficient at the GM, equals to unity (as well as for the charged Kerr hole the gyromagnetic ratio equals to two). The equations of motion obtained for relativistic spinning particle in external gravitational field differ essentially from the Papapetrou equations.Comment: 22 pages, latex, no figure