4,280 research outputs found

    Compact set of invariants characterizing graph states of up to eight qubits

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    The set of entanglement measures proposed by Hein, Eisert, and Briegel for n-qubit graph states [Phys. Rev. A 69, 062311 (2004)] fails to distinguish between inequivalent classes under local Clifford operations if n > 6. On the other hand, the set of invariants proposed by van den Nest, Dehaene, and De Moor (VDD) [Phys. Rev. A 72, 014307 (2005)] distinguishes between inequivalent classes, but contains too many invariants (more than 2 10^{36} for n=7) to be practical. Here we solve the problem of deciding which entanglement class a graph state of n < 9 qubits belongs to by calculating some of the state's intrinsic properties. We show that four invariants related to those proposed by VDD are enough for distinguishing between all inequivalent classes with n < 9 qubits.Comment: REVTeX4, 9 pages, 1 figur

    Features of birth families with foster children in Andalusia

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    The aim of the presentation is to describe the personal features of biological families whose children are in non-kinship foster care and with whom they have face-to-face contact in Málaga, Granada and Jaén (provinces of Andalusia, Spain). This study was funded by the research project Application of a psychoeducational intervention program to improve visits between foster children and their biological families (Reference EDU2016 77094-P). SPSS v.21.0 was used to carry out the descriptive and frequency analysis of socio-demographic information collected by the Child File Summary Form designed for this study. The results show the difficulties experienced by birth families to deal with the responsibility of parenthood. There is a high percentage of unemployment (54.5% mothers, 46.4% fathers), and a low level of education (61.7% uneducated mothers, 68.8% uneducated fathers). Furthermore, it is necessary to consider their diverse personal problems which undermine their competences to bring up and educate their children: substance abuse, mental health issues, mental disability and prison. Finally, the lack of relation between Social Services and birth families is highlighted. Knowing the circumstances of families at psychosocial risk permits to develop social policies that match with their specific necessities, by providing them the support and resources required, in line with Recommendation Rec(2006)19 of the Committee of Ministers to member states. Moreover, children and families’ rights have to be respected, such as their right to have contact to maintain and strengthen their affective bonds as part of their identity. These findings will contribute to design: (a) family intervention programs which allow parents to acquire the necessary parental skills; (b) support and educational tools for the social workers; and (c) projects to contribute to children’s well-being.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Features of non-kinship foster care children with birth family contact in Andalusia

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    The aim of the presentation is to describe the personal features of non-kinship foster care children who have visits with their birth family in Málaga, Granada and Jaén (provinces of Andalusia, Spain). This study was funded by the research project Application of a psychoeducational intervention program to improve visits between foster children and their biological families (Reference EDU2016 77094-P). SPSS v.21.0 was used to carry out the descriptive and frequency analysis of socio-demographic information collected by the Child File Summary Form designed for this study. There are 212 non-kinship foster care children who have visits with their birth family. Their mean age is 8.09 years old (SD= 4.73). The more frequent types of foster care are both long-term and short-term placement (30.7%, respectively), followed by specialized long-term foster care (20.3%), urgency placement (10.8%) and specialized short-term foster care (7.5%). The period of time they have been into the Child Protection System is on average 4.08 years (SD= 3.88) and into the current placement is on average 2.53 (SD= 2.95). Thus, 44.8% of foster children were in residential care and 30.2% were in previous foster care. The latter could have been with the current foster care family. Also, 41.0% of foster children were placed at least with one sibling. It is important to know the features of foster children in order to apply the main principle of “the best interests of the child” to the whole decision-making process about the child’s protection and welfare. In our project, these decisions concern foster care placement and birth family contact to maintain and strengthen family affective bonds and child’s identity formation. Our findings contribute to develop: (a) initiatives to improve children’s well-being; (b) support and social resources required by families; and (c) socio-educative tools for the social workers.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Interpretación crítica de gráficos estadísticos incorrectos en la sociedad de la comunicación: un desafío para futuros maestros

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    La formación de profesores para enseñar estadística en educación primaria debe estar orientada a capacitarlos para que desarrollen la cultura estadística en los alumnos de los primeros ni¬veles educativos. La interpretación de gráficos estadísticos forma parte de la “cultura estadística” (statistical literacy) que cualquier ciudadano debe tener para poder desenvolverse plenamente en la actual sociedad de la información. El logro de este objetivo implica que los profesores de matemáticas deben tener dicha cultura y, además, estar capacitados para desarrollarla en sus alumnos. Esto requiere que los programas de formación de maestros contemplen de manera adecuada, tanto el desarrollo de los conocimientos, destrezas y disposiciones que caracterizan la cultura estadística como los conocimientos y competencias didácticas para diseñar procesos de educación estadística idóneos

    Evidence for a change in the nuclear mass surface with the discovery of the most neutron-rich nuclei with 17<Z <25

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    The results of measurements of the production of neutron-rich nuclei by the fragmentation of a 76-Ge beam are presented. The cross sections were measured for a large range of nuclei including fifteen new isotopes that are the most neutron-rich nuclides of the elements chlorine to manganese (50-Cl, 53-Ar, 55,56-K, 57,58-Ca, 59,60,61-Sc, 62,63-Ti, 65,66-V, 68-Cr, 70-Mn). The enhanced cross sections of several new nuclei relative to a simple thermal evaporation framework, previously shown to describe similar production cross sections, indicates that nuclei in the region around 62-Ti might be more stable than predicted by current mass models and could be an indication of a new island of inversion similar to that centered on 31-Na.Comment: 4 pages, 3 figures, to be published in Physical Review Letters, 200

    Production cross sections of neutron rich isotopes from a 82Se beam

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    Production cross sections for neutron-rich nuclei from the fragmentation of a 82Se beam at 139 MeV/u were measured. The longitudinal momentum distributions of 122 neutron-rich isotopes of elements 11Z3211 \le Z \le 32 were determined by varying the target thickness. Production cross sections with beryllium and tungsten targets were determined for a large number of nuclei including several isotopes first observed in this work. These are the most neutron-rich nuclides of the elements 22Z2522 \le Z \le 25 (64Ti, 67V, 69Cr, 72Mn). One event was registered consistent with 70Cr, and another one with 75Fe. A one-body Qg systematics is used to describe the production cross sections based on thermal evaporation from excited prefragments. The current results confirm those of our previous experiment with a 76Ge beam: enhanced production cross sections for neutron-rich fragments near Z=20.Comment: Talk given at the 11th International Conference on Nucleus-Nucleus Collisions (NN2012), San Antonio, Texas, USA, May 27-June 1, 2012. To appear in the NN2012 Proceedings in Journal of Physics: Conference Series (JPCS

    Shape and structure of N=Z 64Ge; Electromagnetic transition rates from the application of the Recoil Distance Method to knock-out reaction

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    Transition rate measurements are reported for the first and the second 2+ states in N=Z 64Ge. The experimental results are in excellent agreement with large-scale Shell Model calculations applying the recently developed GXPF1A interactions. Theoretical analysis suggests that 64Ge is a collective gamma-soft anharmonic vibrator. The measurement was done using the Recoil Distance Method (RDM) and a unique combination of state-of-the-art instruments at the National Superconducting Cyclotron Laboratory (NSCL). States of interest were populated via an intermediate-energy single-neutron knock-out reaction. RDM studies of knock-out and fragmentation reaction products hold the promise of reaching far from stability and providing lifetime information for excited states in a wide range of nuclei

    TOF-Brho Mass Measurements of Very Exotic Nuclides for Astrophysical Calculations at the NSCL

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    Atomic masses play a crucial role in many nuclear astrophysics calculations. The lack of experimental values for relevant exotic nuclides triggered a rapid development of new mass measurement devices around the world. The Time-of-Flight (TOF) mass measurements offer a complementary technique to the most precise one, Penning trap measurements, the latter being limited by the rate and half-lives of the ions of interest. The NSCL facility provides a well-suited infrastructure for TOF mass measurements of very exotic nuclei. At this facility, we have recently implemented a TOF-Brho technique and performed mass measurements of neutron-rich nuclides in the Fe region, important for r-process calculations and for calculations of processes occurring in the crust of accreting neutron stars.Comment: 8 pages, 4 figures, submitted to Journal of Physics G, proceedings of Nuclear Physics in Astrophysics II
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