Search for Neutrinoless Double- β Decay in Ge 76 with the Majorana Demonstrator

The Majorana Collaboration is operating an array of high purity Ge detectors to search for neutrinoless double-β decay in Ge76. The Majorana Demonstrator comprises 44.1 kg of Ge detectors (29.7 kg enriched in Ge76) split between two modules contained in a low background shield at the Sanford Underground Research Facility in Lead, South Dakota. Here we present results from data taken during construction, commissioning, and the start of full operations. We achieve unprecedented energy resolution of 2.5 keV FWHM at Qββ and a very low background with no observed candidate events in 9.95 kg yr of enriched Ge exposure, resulting in a lower limit on the half-life of 1.9×1025 yr (90% C.L.). This result constrains the effective Majorana neutrino mass to below 240-520 meV, depending on the matrix elements used. In our experimental configuration with the lowest background, the background is 4.0-2.5+3.1 counts/(FWHM t yr)

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Survey of curriculum management styles in selected rural primary schools

Prelim. reportAppendices are in Bahasa Malaysia

Research on cancer diagnosis in Malaysia: current status.

Cancer is a major morbidity and mortality concern in Malaysia. Based on National Cancer Registry data, the Malaysian population is estimated to bear a cancer burden of about 40,000 new cases per year, and a cumulative lifetime risk of about 1:4. Cancer research in Malaysia has to consider needs relevant to our population, and resources constraints. Hence, funding bodies prioritise cancers of high prevalence, unique to our community and posing specific clinical problems. Cancer diagnosis is crucial to cancer management. While cancer diagnosis research largely aims at improvements in diagnostic information towards more appropriate therapy, it also impacts upon policy development and other areas of cancer management. The scope of cancer diagnosis upon which this paper is based, and their possible impact on other R&D areas, has been broadly categorized into: (1) identification of aetiological agents and their linkages to the development of precancer and cancer (impact on policy development, cancer prevention and treatment), (2) cancer biology and pathogenesis (impact on cancer prevention, treatment strategies and product development), (3) improvements in accuracy, sensitivity and specificity in cancer detection, monitoring and classification (impact on technology development) and (4) prognostic and predictive parameters (impact on treatment strategies). This paper is based on data collected by the Working Group on Cancer Diagnosis Research for the First National Conference on Cancer Research Coordination in April 2004. Data was collated from the databases of Institutions/Universities where the authors are employed, the Ministry of Science, Technology and Innovation (MOSTI) and targeted survey feedback from key cancer researchers. Under the 7th Malaysia Plan, 76 cancer projects were funded through the Intensified Research in Priority Areas (IRPA) scheme of MOSTI, amounting to almost RM15 million of grant money. 47(61.8%) of these projects were substantially in cancer diagnosis, accounting for 65.6% (RM 9.7 million) of cancer project funds. The 8th Malaysia Plan saw a change in research strategy. The IRPA agency fielded several top-down projects which encouraged a multicentre and multidisciplinary approach. This resulted in larger funding per project i.e. RM32 million for 49 projects. There was also a surge of interest in drug development and natural products. Because of this shift in direction, cancer diagnosis projects constituted only 51% of IRPA-funded cancer projects. Nonetheless funding for cancer diagnosis research has exceeded that of the 7th Malaysia Plan, being RM12.5 million by March 2004. The majority of such research is carried out at the Universities, engaging a large number of young scientists and postgraduate students (51 MSc and 21 PhD). A lot of research findings presented at scientific meetings have not yet been published and there is a glaring shortage of patents and commercialization of research findings (such as creation of test kits). Because diagnosis is very much a part of clinical practice, many researchers felt satisfied and confident that their work will be translated into practice and will significantly improve diagnostic services in Malaysia. National guidelines and consensus development on at least three malignancies i.e. breast cancer, oral cancer and lymphoma, have substantial basis in local R&D work. Problems encountered in research included (1) insufficient funding to realize research objectives, (2) lack of local expertise (most research assistants are inexperienced BSc graduates with no or minimal research experience), (3) inadequate technical support from vendors during equipment failure, (4) inexperienced Institutional development units to assist in product development, (5) lack of venture capital for commercialization of findings, and (6) inadequate incentives to undertake research. Researchers pointed out that plans to promote research should include the establishment of (1) regional and national cancer tissue banks, (2) a National Cancer Research Institute, (3) a dedicated cancer research fund, (4) a registry of cancer researchers, (5) national research coordinators, (6) improved coverage by the National Cancer Registry, (7) more international collaboration, (8) a better career structure for researchers, (9) improved Institutional support for product realization, and (10) better recognition for cancer researchers

The Majorana Demonstrator Status and Preliminary Results

The Majorana Collaboration is using an array of high-purity Ge detectors to search for neutrinoless double-beta decay in 76Ge. Searches for neutrinoless double-beta decay are understood to be the only viable experimental method for testing the Majorana nature of the neutrino. Observation of this decay would imply violation of lepton number, that neutrinos are Majorana in nature, and provide information on the neutrino mass. The Majorana Demonstrator comprises 44.1 kg of p-type point-contact Ge detectors (29.7 kg enriched in 76Ge) surrounded by a low-background shield system. The experiment achieved a high efficiency of converting raw Ge material to detectors and an unprecedented detector energy resolution of 2.5 keV FWHM at Qββ. The Majorana collaboration began taking physics data in 2016. This paper summarizes key construction aspects of the Demonstrator and shows preliminary results from initial data

Multisite event discrimination for the majorana demonstrator

The Majorana Demonstrator is searching for neutrinoless double-beta decay (0νββ) in Ge76 using arrays of point-contact germanium detectors operating at the Sanford Underground Research Facility. Background results in the 0νββ region of interest from data taken during construction, commissioning, and the start of full operations have been recently published. A pulse shape analysis cut applied to achieve this result, named AvsE, is described in this paper. This cut is developed to remove events whose waveforms are typical of multisite energy deposits while retaining (90±3.5)% of single-site events. This pulse shape discrimination is based on the relationship between the maximum current and energy, and tuned using Th228 calibration source data. The efficiency uncertainty accounts for variation across detectors, energy, and time, as well as for the position distribution difference between calibration and 0νββ events, established using simulations

The Majorana Demonstrator Status and Preliminary Results

The Majoran

Search for neutrinoless double- β decay in Ge 76 with 26 kg yr of exposure from the M ajorana D emonstrator SEARCH for NEUTRINOLESS DOUBLE- β DECAY ... S. I. ALVIS et al.

The Majorana Collaboration is operating an array of high-purity Ge detectors to search for the neutrinoless double-β decay of Ge76. The Majorana Demonstrator consists of 44.1 kg of Ge detectors (29.7 kg enriched to 88% in Ge76) split between two modules constructed from ultraclean materials. Both modules are contained in a low-background shield at the Sanford Underground Research Facility in Lead, South Dakota. We present updated results on the search for neutrinoless double-β decay in Ge76 with 26.0±0.5 kg yr of enriched exposure. With the Demonstrator's energy resolution of 2.53 keV FWHM at Qββ, which is the best among all neutrinoless double-β decay experiments, we observe one event in the region of interest with 0.65 events expected from the estimated background, resulting in a lower limit on the Ge76 neutrinoless double-β decay half-life of 2.7×1025 yr [90% confidence level (CL)] with a median sensitivity of 4.8×1025 yr (90% CL). Depending on the matrix elements used, a 90% CL upper limit on the effective Majorana neutrino mass in the range of 200-433 meV is obtained. The measured background in the configurations with full shielding and optimized grounding is 11.9±2.0 counts/(FWHM t yr)

Search for trinucleon decay in the Majorana Demonstrator

The Majorana Demonstrator is an ultra-low-background experiment searching for neutrinoless double-beta decay in Ge76. The heavily shielded array of germanium detectors, placed nearly a mile underground at the Sanford Underground Research Facility in Lead, South Dakota, also allows searches for new exotic physics. We present the first limits for trinucleon decay-specific modes and invisible decay modes for Ge isotopes. We find a half-life limit of 4.9×1025 yr for the decay Ge76(ppn)→Zn73 e+π+ and 4.7×1025 yr for the decay Ge76(ppp)→Cu73 e+π+π+. The half-life limit for the invisible triproton decay mode of Ge76 was found to be 7.5×1024 yr