Double beta decay to the excited states: experimental review

A brief review on double beta decay to excited states of daughter nuclei is given. The ECEC(ov) transision to the excited states are discussed in association with a possible enhancement of the decay rate by several orders of magnitude.Comment: 5 pages; talk at MEDEX'07 ("Matrix Elements for the Double-beta-decay Experiments"; Prague, June 11-14, 2007

Improved short-range correlations and 0nbb nuclear matrix elements of 76Ge and 82Se

We calculate the nuclear matrix elements of the neutrinoless double beta ($0\nu\beta\beta$) decays of $^{76}$Ge and $^{82}$Se for the light-neutrino exchange mechanism. The nuclear wave functions are obtained by using realistic two-body forces within the proton-neutron quasiparticle random-phase approximation (pnQRPA). We include the effects that come from the finite size of a nucleon, from the higher-order terms of nucleonic weak currents, and from the nucleon-nucleon short-range correlations. Most importantly, we improve on the presently available calculations by replacing the rudimentary Jastrow short-range correlations by the more advanced unitary correlation operator method (UCOM). The UCOM corrected matrix elements turn out to be notably larger in magnitude than the Jastrow corrected ones. This has drastic consequences for the detectability of $0\nu\beta\beta$ decay in the present and future double beta experiments.Comment: 5 pages, 2 figures, to appear in Physical Review C (Rapid Communication) 200

Nuclear matrix elements of neutrinoless double beta decay with improved short-range correlations

Nuclear matrix elements of the neutrinoless double beta decays of 96Zr, 100Mo, 116Cd, 128Te, 130Te and 136Xe are calculated for the light-neutrino exchange mechanism by using the proton-neutron quasiparticle random-phase approximation (pnQRPA) with a realistic nucleon-nucleon force. The g_pp parameter of the pnQRPA is fixed by the data on the two-neutrino double beta decays and single beta decays. The finite size of a nucleon, the higher-order terms of nucleonic weak currents, and the nucleon-nucleon short-range correlations (s.r.c) are taken into account. The s.r.c. are computed by the traditional Jastrow method and by the more advanced unitary correlation operator method (UCOM). Comparison of the results obtained by the two methods is carried out. The UCOM computed matrix elements turn out to be considerably larger than the Jastrow computed ones. This result is important for the assessment of the neutrino-mass sensitivity of the present and future double beta experiments.Comment: Two figures, to be published in Physical Review C (2007) as a regular articl

On nuclear matrix element uncertainties in short range 0vBB decay

The evaluation of short range contributions to neutrinoless double beta decay has been challenged due to critics of the ansatz of the nuclear matrix element calculations. We comment on the critics and uncertainties of these calculations and the effect on the derived limits.Comment: 3 pages, Latex, new arguments adde

In-Medium Similarity Renormalization Group with Chiral Two- Plus Three-Nucleon Interactions

We use the recently proposed In-Medium Similarity Renormalization Group (IM-SRG) to carry out a systematic study of closed-shell nuclei up to \nuc{Ni}{56}, based on chiral two- plus three-nucleon interactions. We analyze the capabilities of the IM-SRG by comparing our results for the ground-state energy to Coupled Cluster calculations, as well as to quasi-exact results from the Importance-Truncated No-Core Shell Model. Using chiral two- plus three-nucleon Hamiltonians whose resolution scales are lowered by free-space SRG evolution, we obtain good agreement with experimental binding energies in \nuc{He}{4} and the closed-shell oxygen isotopes, while the calcium and nickel isotopes are somewhat overbound.Comment: 11 pages, 7 figures, submitted to Phys. Rev.

Magnetic excitations in nuclei with neutron excess

The excitation of the $1^+$, $2^-$ and $3^+$ modes in $^{16}$O, $^{22}$O, $^{24}$O, $^{28}$O, $^{40}$Ca, $^{48}$Ca, $^{52}$Ca and $^{60}$Ca nuclei is studied with self-consistent random phase approximation calculations. Finite-range interactions of Gogny type, containing also tensor-isospin terms, are used. We analyze the evolution of the magnetic resonances with the increasing number of neutrons, the relevance of collective effects, the need of a correct treatment of the continuum and the role of the tensor force.Comment: 18 pages, 12 figures, 2 tables, accepted for publication in Physical Review

Ihminen ja asumus:tutkielmia rajautumisen arkkitehtuurista

Tiivistelmä. Diplomityöni Ihminen ja asumus — Tutkielmia rajautumisen arkkitehtuurista on luonteeltaan tutkielmamuotoinen työ, jonka tavoitteena on tutkia rajan merkitystä ja ilmenemistä asumisen arkkitehtuurissa. Työni pääasiallinen lähestymistapa on otteeltaan fenomenologinen eli kirjallisen aineiston ja teoreettisen viitekehyksen lisäksi olen tukeutunut omiin havaintoihini ja kokemuksiini. Diplomityöni jakaantuu kahteen tasavahvaan osaan. Ensimmäisessä osassa tarkastelen kirjallisuuden ja havaintojeni kautta asukkaan suhdetta asumukseensa biologisista ja filosofisista lähtökohdista. Näiden lähtökohtien pohjalta käsittelen asumuksen rajoihin kohdistuvia tarpeita ja vaatimuksia ja esittelen niistä kumpuavia rajan arkkitehtuurin ominaisuuksia. Lisäksi pohdin arkkitehtuurin ilmenemistä asumuksen rajautumisen kontekstissa. Työni toisen osan muodostavat research by design -periaatetta noudattavat konseptitutkielmat. Kolme tutkielmaa koostuvat yhteensä viidestä itsenäisestä pienoismallista, joiden kautta avaan työni ensimmäisessä osassa esittelemiäni asumuksen rajautumisen teemoja. Valokuvien ja piirrosten kautta esittelen prosessin ja tutkimusaineiston pohjalta tekemiäni havaintoja ja johtopäätöksiä. Työni toisessa osassa haen myös menetelmän kautta uudenlaisia analyysi- ja ratkaisutapoja teoreettisen tiedon siirtämiseksi käytännön suunnittelutyöhön soveltuvin osin.Man and dwelling : studies of boundaries in architecture. Abstract. My diploma thesis, Man and dwelling — Studies of Boundaries in Architecture is a study of relevance and meaning of architectural form in the boundaries of dwelling. In this thesis my aim is to perceive and characterize these forms. The main approach of my thesis is phenomenological and alongside literary and theoretical framework my personal perceptions take place in the studies. This diploma thesis is divided in two equal parts. In the first part of my thesis I will consider the relationship between man and dwelling concurrently from biological and philosophical basis. This consideration is made through literature and my personal perceptions. Throughout my thesis I will highlight the demands and expectations that meet the boundaries of dwelling and present attributes of architecture derived from this research. Furthermore, I will consider the manifesting forms of architecture derived from these focal points. The second part of my thesis is a collection of concept studies following the principles of research by design. The three concept studies consist of five independent models, through which I will present the themes of boundaries found in dwellings that were first introduced in the first part of my thesis. I will present the process and observations made from the analysis through photographs and drawings of the concept studies. In the process of research by design I sought for new ways of analysis and a new interface between theoretical knowledge and designing architecture

The impact of mobile devices for learning in higher education institutions : Nigerian universities case study

Mobile devices such as smartphones and tablets are becoming increasing popular among students, setting out a new way to communicate, collaborate and learn. The use of portable devices has the capability to inspire new approaches to learning. It is therefore important to examine the students’ viewpoints about the educational use of mobile technology in supporting the learning process. The purpose of this study is to determine the impact of mobile devices for learning purposes by exploring the kinds of interactions that students in Nigerian universities have with their portable gadgets. A sample of 240 higher education students participated in the study by completing the researchers’ questionnaire. The results of the study indicate the students use their portable devices to exchange education-related messages and academic files with classmates, search the internet and library databases for academic materials, practice online quizzes or tests and hold discussions with classmates among others. The statistical analyses result show that there is no significant difference in the students’ use of mobile devices based on gender

Discovering students mobile learning experiences in higher education in Nigeria

M-learning plays a progressively significant role in the advancement of teaching and learning in higher education. However, the effective implementation of m-learning in higher education will be based on users’ experiences and motivation to use this technology. Though m-learning has become global, developing countries such as Nigeria are yet to enjoy the full potential offered by m-learning. This study is focused on ascertaining students’ experiences with m-learning, determining the influence of m-learning on students’ motivations and interests, and identifying factors that are limiting m-learning adoption in Nigeria. We investigated these experiences by analysing questionnaires collected from undergraduate and postgraduate students of six universities in Nigeria. The results from our study show that the students own and use diverse mobile devices to engage in educational activities and other social networking purposes. Some of these learning activities are sending SMS messages, playing educational games, social learning, reading e-books/pdfs, and completing assignments and quizzes. Students expressed their satisfaction with m-learning especially for supporting them to learn anywhere, anytime. They further confirmed that m-learning motivates, interests, and inspires every aspect of learning. Furthermore, the students acknowledges that the interactivity, flexibility, convenience and engagement of m-learning were authentic learning experiences

Ethical issues related to the use of gerontechnology in older people care: A scoping review

Background:Demographic trends indicate growth of population aged 65 and older in Western countries. One of the greatest challenges is to provide high-quality care for all. Technological solutions designed for older people, gerontechnology, can somewhat balance the gap between resources and the increasing demand of healthcare services. However, there are also ethical issues in the use of gerontechnology that need to be pointed out.Purpose:To describe what ethical issues are related to the use of gerontechnology in the care of community-dwelling older people.Methods:A scoping review was performed to identify and analyse studies concerning ethical issues when using gerontechnology in the home care of older people. The literature search was limited to studies published after 1990 and addressed to the electronic databases CINAHL, PubMed, Cochrane, Medic, IEEE Explore and Web of Science. The search was performed in July−August 2018. Data from empirical studies were analysed using thematic analysis.Ethical considerations:This scoping review was conducted in accordance with good scientific practice. The work of other researchers was respected and cited appropriately.Results:A total of 17 studies were identified. Two main themes were found. ‘Balancing between the benefits of using gerontechnology and the basic rights of older people’, consisted of the subthemes safety, privacy and autonomy. The other main theme, ‘Gerontechnology as a risk of insecurity for older people’, included the subthemes fear of losing human contact and concern and fear. Surveillance and monitoring technologies were mainly studied.Conclusion:These results suggest that there may be ethical issues related to the use of gerontechnology and they must therefore be taken into consideration when implementing technology in the care of community-dwelling older people.</div