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1.
Eur Phys J C Part Fields ; 84(9): 940, 2024.
Article in English | MEDLINE | ID: mdl-39309033

ABSTRACT

A search for full energy depositions from bosonic keV-scale dark matter candidates of masses between 65 and 1021 keV has been performed with data collected during Phase II of the GERmanium Detector Array (Gerda) experiment. Our analysis includes direct dark matter absorption as well as dark Compton scattering. With a total exposure of 105.5 kg years, no evidence for a signal above the background has been observed. The resulting exclusion limits deduced with either Bayesian or Frequentist statistics are the most stringent direct constraints in the major part of the 140-1021 keV mass range. As an example, at a mass of 150 keV the dimensionless coupling of dark photons and axion-like particles to electrons has been constrained to α ' / α < 8.7 × 10 - 24 and g ae < 3.3 × 10 - 12 at 90% credible interval (CI), respectively. Additionally, a search for peak-like signals from beyond the Standard Model decays of nucleons and electrons is performed. We find for the inclusive decay of a single neutron in 76 Ge a lower lifetime limit of τ n > 1.5 × 10 24 years and for a proton τ p > 1.3 × 10 24 years at 90% CI. For the electron decay e - → ν e γ a lower limit of τ e > 5.4 × 10 25 years at 90% CI has been determined. Supplementary Information: The online version contains supplementary material available at 10.1140/epjc/s10052-024-13020-0.

2.
Hong Kong Med J ; 30(4): 310-319, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39138142

ABSTRACT

Overactive bladder (OAB) is a common urological disease with a high prevalence in older adult populations. Antimuscarinic drugs have been the most common treatment for OAB for more than a decade, but their anticholinergic side-effects and potential impact on cognitive function among older patients are usually underestimated. This consensus aimed to provide practical recommendations concerning OAB management, with a particular emphasis on older patients. A joint consensus panel was formed by representatives of the Hong Kong Urological Association and the Hong Kong Geriatrics Society. Literature searches regarding OAB and its management were performed in PubMed and Ovid. Several working meetings were held to present and discuss available evidence, develop consensus statements, and vote for the statements. A modified Delphi method was used in this consensus process. To address questions regarding various aspects of OAB, 29 consensus statements were proposed covering the following areas: diagnosis, initial assessment, non-pharmacological treatments, considerations before administration of pharmacological treatments, various pharmacological treatments, combination therapy, and surgical treatment. Twenty-five consensus statements were accepted.


Subject(s)
Geriatrics , Muscarinic Antagonists , Urinary Bladder, Overactive , Humans , Urinary Bladder, Overactive/therapy , Urinary Bladder, Overactive/drug therapy , Urinary Bladder, Overactive/diagnosis , Hong Kong , Muscarinic Antagonists/therapeutic use , Aged , Geriatrics/standards , Consensus , Societies, Medical , Delphi Technique , Urology/standards
4.
Hong Kong Med J ; 30(3): 227-232, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38725395

ABSTRACT

INTRODUCTION: This study evaluated the perioperative and early postoperative outcomes of transurethral water vapour thermal therapy (WVTT) under local anaesthesia alone for benign prostatic enlargement in Chinese patients. METHODS: This retrospective review of transurethral WVTT for benign prostatic enlargement focused on 50 Chinese patients who exhibited clinical indications (acute retention of urine or symptomatic lower urinary tract symptoms due to benign prostatic enlargement) for surgical treatment between June 2020 and December 2021 in Hong Kong. Exclusion criteria included active urinary tract problems and urological malignancies. Follow-up was conducted at 3 months postoperatively. RESULTS: The median patient age was 71.5 years. The mean preoperative prostatic volume was 56.7 mL. The mean operation time was 25.1 minutes. All procedures were performed under local anaesthesia alone. The mean pain scores for transrectal ultrasound probe insertion, transperineal local anaesthesia injection, and transurethral WVTT were 2, 5, and 4, respectively. Forty-nine patients (98%) were discharged on the same day with a urethral catheter. Forty-eight patients (96%) successfully completed a trial without catheter within 3 weeks postoperatively. Five patients (10%) had unplanned hospital admission within 30 days postoperatively due to surgical complications (Clavien-Dindo grade 1). CONCLUSION: Transurethral WVTT, an advanced surgical treatment for benign prostatic enlargement, is a safe procedure that relieves lower urinary tract symptoms with minimal hospital stay. It can be performed in an office-based setting under local anaesthesia, maximising utilisation of the surgical theatre.


Subject(s)
Anesthesia, Local , Prostatic Hyperplasia , Humans , Male , Prostatic Hyperplasia/surgery , Prostatic Hyperplasia/therapy , Aged , Retrospective Studies , Hong Kong , Anesthesia, Local/methods , Middle Aged , Transurethral Resection of Prostate/methods , Transurethral Resection of Prostate/adverse effects , Treatment Outcome , Hyperthermia, Induced/methods , Hyperthermia, Induced/adverse effects , Lower Urinary Tract Symptoms/etiology , Lower Urinary Tract Symptoms/therapy , Lower Urinary Tract Symptoms/surgery , Aged, 80 and over , Operative Time , Steam , East Asian People
5.
Eur Phys J C Part Fields ; 84(1): 18, 2024.
Article in English | MEDLINE | ID: mdl-38205101

ABSTRACT

High-precision searches for an electric dipole moment of the neutron (nEDM) require stable and uniform magnetic field environments. We present the recent achievements of degaussing and equilibrating the magnetically shielded room (MSR) for the n2EDM experiment at the Paul Scherrer Institute. We present the final degaussing configuration that will be used for n2EDM after numerous studies. The optimized procedure results in a residual magnetic field that has been reduced by a factor of two. The ultra-low field is achieved with the full magnetic-field-coil system, and a large vacuum vessel installed, both in the MSR. In the inner volume of ∼1.4m3, the field is now more uniform and below 300 pT. In addition, the procedure is faster and dissipates less heat into the magnetic environment, which in turn, reduces its thermal relaxation time from 12h down to 1.5h.

6.
Phys Rev Lett ; 131(19): 191801, 2023 Nov 10.
Article in English | MEDLINE | ID: mdl-38000426

ABSTRACT

Models that postulate the existence of hidden sectors address contemporary questions, such as the source of baryogenesis and the nature of dark matter. Neutron-to-hidden-neutron oscillations are among the possible mixing processes and have been tested with ultracold neutron storage and passing-through-wall experiments to set constraints on the oscillation period τ_{nn^{'}}. These searches probe the oscillations as a function of the mass splitting due to the neutron-hidden-neutron energy degeneracy. In this work, we present a new limit derived from neutron disappearance in ultracold neutron beam experiments. The overall limit, given by τ_{nn^{'}}>1 s for |δm|∈[2,69] peV(95.45% C.L.), covers the yet unexplored intermediate mass-splitting range and contributes to the ongoing research on hidden sectors.

7.
Eur Phys J C Part Fields ; 83(11): 1061, 2023.
Article in English | MEDLINE | ID: mdl-38021215

ABSTRACT

We present a novel Active Magnetic Shield (AMS), designed and implemented for the n2EDM experiment at the Paul Scherrer Institute. The experiment will perform a high-sensitivity search for the electric dipole moment of the neutron. Magnetic-field stability and control is of key importance for n2EDM. A large, cubic, 5 m side length, magnetically shielded room (MSR) provides a passive, quasi-static shielding-factor of about 105 for its inner sensitive volume. The AMS consists of a system of eight complex, feedback-controlled compensation coils constructed on an irregular grid spanned on a volume of less than 1000 m3 around the MSR. The AMS is designed to provide a stable and uniform magnetic-field environment around the MSR, while being reasonably compact. The system can compensate static and variable magnetic fields up to ±50µT (homogeneous components) and ±5µT/m (first-order gradients), suppressing them to a few µT in the sub-Hertz frequency range. The presented design concept and implementation of the AMS fulfills the requirements of the n2EDM experiment and can be useful for other applications, where magnetically silent environments are important and spatial constraints inhibit simpler geometrical solutions.

8.
Phys Rev Lett ; 131(14): 142501, 2023 Oct 06.
Article in English | MEDLINE | ID: mdl-37862664

ABSTRACT

We present the measurement of the two-neutrino double-ß decay rate of ^{76}Ge performed with the GERDA Phase II experiment. With a subset of the entire GERDA exposure, 11.8 kg yr, the half-life of the process has been determined: T_{1/2}^{2ν}=(2.022±0.018_{stat}±0.038_{syst})×10^{21} yr. This is the most precise determination of the ^{76}Ge two-neutrino double-ß decay half-life and one of the most precise measurements of a double-ß decay process. The relevant nuclear matrix element can be extracted: M_{eff}^{2ν}=(0.101±0.001).

9.
Eur Phys J C Part Fields ; 83(9): 778, 2023.
Article in English | MEDLINE | ID: mdl-37674593

ABSTRACT

We search for tri-nucleon decays of 76Ge in the dataset from the GERmanium Detector Array (GERDA) experiment. Decays that populate excited levels of the daughter nucleus above the threshold for particle emission lead to disintegration and are not considered. The ppp-, ppn-, and pnn-decays lead to 73Cu, 73Zn, and 73Ga nuclei, respectively. These nuclei are unstable and eventually proceed by the beta decay of 73Ga to 73Ge (stable). We search for the 73Ga decay exploiting the fact that it dominantly populates the 66.7 keV 73mGa state with half-life of 0.5 s. The nnn-decays of 76Ge that proceed via 73mGe are also included in our analysis. We find no signal candidate and place a limit on the sum of the decay widths of the inclusive tri-nucleon decays that corresponds to a lower lifetime limit of 1.2×1026 yr  (90% credible interval). This result improves previous limits for tri-nucleon decays by one to three orders of magnitude.

10.
Hong Kong Med J ; 29(4): 311-321, 2023 08.
Article in English | MEDLINE | ID: mdl-37532669

ABSTRACT

INTRODUCTION: We conducted translation and psychometric validation of a self-administered, 22-item dichotomous response-based questionnaire to identify nocturia aetiologies and co-morbidities in adult patients. METHODS: The Targeting the individual's Aetiology of Nocturia to Guide Outcomes (TANGO) questionnaire was forward- and backward-translated, then finalised using a standardised methodology. The resulting version, a Chinese version of the TANGO [TANGO (CV)], was evaluated for internal consistency, test-retest reliability, content validity, convergent validity, criterion validity, and discriminant validity via responses from 65 participants (46 men and 19 women; mean age, 67 years, range, 50-88), in comparison with other validated questionnaires and a 4-day bladder/sleep diary. RESULTS: Only 0.4% of responses were missing; 3% of participants required assistance with comprehension. The Kuder-Richardson Formula 20 (KR-20) coefficient for the whole tool was 0.711. Kappa values for individual domains and the whole tool varied from 0.871 to 0.866, indicating satisfactory test-retest reliability. There was strong agreement between the sum of positive responses to each domain and the whole tool (intra-class correlation coefficient=0.878-1.000). Modest correlations (ρ=0.4-0.6) were detected between the tool and bladder/sleep diary-based parameters for convergent validity. Criterion validity was confirmed for each domain and the whole tool [ρ=0.287-0.687]. In receiver operating characteristic analysis, the tool could distinguish patients (≥2 nocturia episodes/night) from controls (≤1 nocturia episode/night) [Youden's J statistic=0.453, area under the curve=0.818, 95% confidence interval (CI)=0.683-0.953] and patients with significant nocturia distress from patients with mild nocturia distress (Youden's J statistic=0.398, area under the curve=0.729, 95% CI=0.581-0.878). CONCLUSION: The TANGO (CV) was formally crossculturally adapted and translated. Its psychometric properties (except sensitivity to change) were validated.


Subject(s)
Nocturia , Adult , Male , Humans , Female , Aged , Nocturia/diagnosis , Nocturia/etiology , Cross-Cultural Comparison , Psychometrics , Reproducibility of Results , Surveys and Questionnaires
11.
Hong Kong Med J ; 29(4): 324-329, 2023 08.
Article in English | MEDLINE | ID: mdl-37424071

ABSTRACT

INTRODUCTION: Prostate-specific antigen-based screening for prostate cancer reportedly does not improve cancer-specific survival. However, there remain concerns about the increasing incidence of advanced disease at initial presentation. Here, we investigated the incidences and types of complications that occur during the course of disease in patients with metastatic hormone-sensitive prostate cancer (mHSPC). METHODS: This study included 100 consecutive patients who were diagnosed with mHSPC at five hospitals from January 2016 to August 2017. Analyses were conducted using patient data extracted from a prospectively collected database, along with information about complications and readmission obtained from electronic medical records. RESULTS: The median patient age was 74 years and the median serum prostate-specific antigen level at diagnosis was 202.5 ng/mL. Ninety-nine patients received androgen deprivation therapy; 17 of these patients also received chemotherapy. During a mean follow-up period of 32.9 months, 41 patients reported bone pain; of these patients, 21 developed pathologic fractures and eight had cord compression. Twenty-eight patients developed retention of urine; of these patients, 10 (36%) required surgery and 11 (39%) required long-term urethral catheter use. Among 15 patients who developed ureteral obstruction, four (27%) required ureteral stenting and four (27%) required long-term nephrostomy drainage. Other complications included anaemia (41%) and deep vein thrombosis (4%). Fifty-nine (59%) patients had ≥1 unplanned hospital admission during the course of disease; 16% of such patients had >5 episodes of readmission. CONCLUSION: Among patients with mHSPC, 70% experienced disease-related complications and unplanned hospital admissions, which substantially burdened both patients and the healthcare system.


Subject(s)
Prostatic Neoplasms , Male , Humans , Aged , Prostatic Neoplasms/complications , Prostatic Neoplasms/drug therapy , Prostate-Specific Antigen , Androgen Antagonists/adverse effects , Hormones/therapeutic use
12.
Hong Kong Med J ; 29(4): 359.e1-359.e3, 2023 08.
Article in English | MEDLINE | ID: mdl-37316159
13.
Hong Kong Med J ; 29(3): 208-213, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37349137

ABSTRACT

INTRODUCTION: Didactic lectures have been the foundation of learning for many medical students. However, in recent years, the flipped classroom model has become increasingly popular in medical education. This approach enhances pre-class learning, allowing the limited contact time between clinicians and medical students to be focused on practical issues. This study evaluated the effectiveness and non-inferiority of online micromodule teaching in terms of knowledge transfer concerning specific urology topics. METHODS: Medical students without prior exposure to the urology subspecialty were enrolled in the study, then randomised to a traditional didactic lecture group or an online micromodule group. Knowledge transfer was assessed by pre-intervention and post-intervention multiple-choice questions and objective structured clinical examinations that involved the acquisition of medical histories from real patients. RESULTS: In total, 45 medical students were enrolled (22 in the traditional didactic group and 23 in the online micromodule group). In terms of knowledge transfer (assessed by objective structured clinical examinations), the efficacy of online micromodules was comparable to traditional didactic lectures, although the difference was not statistically significant (P=0.823). There were no significant differences in terms of knowledge acquisition, retention, or clinical application between the two groups. CONCLUSION: In terms of acquiring, retaining, and applying foundational urological knowledge, online micromodules can help medical students to achieve outcomes comparable with the outcomes of didactic lectures. Online micromodules may be a viable alternative to traditional didactic lectures in urology education.


Subject(s)
Education, Medical , Students, Medical , Humans , Feasibility Studies , Learning , Educational Status , Curriculum
14.
Eur Phys J C Part Fields ; 83(4): 319, 2023.
Article in English | MEDLINE | ID: mdl-37122826

ABSTRACT

The ability to detect liquid argon scintillation light from within a densely packed high-purity germanium detector array allowed the Gerda experiment to reach an exceptionally low background rate in the search for neutrinoless double beta decay of 76 Ge. Proper modeling of the light propagation throughout the experimental setup, from any origin in the liquid argon volume to its eventual detection by the novel light read-out system, provides insight into the rejection capability and is a necessary ingredient to obtain robust background predictions. In this paper, we present a model of the Gerda liquid argon veto, as obtained by Monte Carlo simulations and constrained by calibration data, and highlight its application for background decomposition.

15.
Hong Kong Med J ; 29(2): 174.e1-174.e3, 2023 04.
Article in English | MEDLINE | ID: mdl-37088704

Subject(s)
Dementia, Vascular , Humans
17.
Rev Sci Instrum ; 93(9): 095105, 2022 Sep 01.
Article in English | MEDLINE | ID: mdl-36182526

ABSTRACT

We present the magnetically shielded room (MSR) for the n2EDM experiment at the Paul Scherrer Institute, which features an interior cubic volume with each side of length 2.92 m, thus providing an accessible space of 25 m3. The MSR has 87 openings of diameter up to 220 mm for operating the experimental apparatus inside and an intermediate space between the layers for housing sensitive signal processing electronics. The characterization measurements show a remanent magnetic field in the central 1 m3 below 100 pT and a field below 600 pT in the entire inner volume, up to 4 cm to the walls. The quasi-static shielding factor at 0.01 Hz measured with a sinusoidal 2 µT peak-to-peak signal is about 100 000 in all three spatial directions and increases rapidly with frequency to reach 108 above 1 Hz.

18.
Eur Phys J C Part Fields ; 81(6): 512, 2021.
Article in English | MEDLINE | ID: mdl-34720721

ABSTRACT

We present the design of a next-generation experiment, n2EDM, currently under construction at the ultracold neutron source at the Paul Scherrer Institute (PSI) with the aim of carrying out a high-precision search for an electric dipole moment of the neutron. The project builds on experience gained with the previous apparatus operated at PSI until 2017, and is expected to deliver an order of magnitude better sensitivity with provision for further substantial improvements. An overview is of the experimental method and setup is given, the sensitivity requirements for the apparatus are derived, and its technical design is described.

19.
Eur Phys J A Hadron Nucl ; 57(4): 152, 2021.
Article in English | MEDLINE | ID: mdl-34776778

ABSTRACT

Psychological bias towards, or away from, prior measurements or theory predictions is an intrinsic threat to any data analysis. While various methods can be used to try to avoid such a bias, e.g. actively avoiding looking at the result, only data blinding is a traceable and trustworthy method that can circumvent the bias and convince a public audience that there is not even an accidental psychological bias. Data blinding is nowadays a standard practice in particle physics, but it is particularly difficult for experiments searching for the neutron electric dipole moment (nEDM), as several cross measurements, in particular of the magnetic field, create a self-consistent network into which it is hard to inject a false signal. We present an algorithm that modifies the data without influencing the experiment. Results of an automated analysis of the data are used to change the recorded spin state of a few neutrons within each measurement cycle. The flexible algorithm may be applied twice (or more) to the data, thus providing the option of sequentially applying various blinding offsets for separate analysis steps with independent teams. The subtle manner in which the data are modified allows one subsequently to adjust the algorithm and to produce a re-blinded data set without revealing the initial blinding offset. The method was designed for the 2015/2016 measurement campaign of the nEDM experiment at the Paul Scherrer Institute. However, it can be re-used with minor modification for the follow-up experiment n2EDM, and may be suitable for comparable projects elsewhere.

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