589 research outputs found
Why doorstepping can increase household waste recycling
AbstractIn this study we report on a doorstepping intervention which produced a 12.5%, statistically significant, increase in the recycling capture rate. More importantly, we investigate why doorstepping caused the increase, through focus groups, structured interviews and questionnaires. By analyzing the findings with respect to a pragmatic set of eleven clusters of determinants of behaviour change, we find that social norms and emotion were important, with prompts as a more minor determinant. We can now plan further doorstepping knowing an emphasis on these is useful. Knowledge, skills, belief of consequences, belief of capability, action planning, role clarification, feedback, and motivation were determinant clusters found not to be important in this case.Recycling behaviour change interventions often do not generally produce transferable learning because they are usually presented as case studies and not broken down into key elements. Our analytical approach of breaking down a poorly defined activity – doorstepping – into elements which influence different clusters of determinants, and then exploring their separate impacts, allows some predictive planning and optimization for other interventions. The specific context here was residential food waste recycling in apartment blocks of communities in Shanghai, China
Classification of a supersolid: Trial wavefunctions, Symmetry breakings and Excitation spectra
A state of matter is characterized by its symmetry breaking and elementary
excitations.
A supersolid is a state which breaks both translational symmetry and internal
symmetry.
Here, we review some past and recent works in phenomenological
Ginsburg-Landau theories, ground state trial wavefunctions and microscopic
numerical calculations. We also write down a new effective supersolid
Hamiltonian on a lattice.
The eigenstates of the Hamiltonian contains both the ground state
wavefunction and all the excited states (supersolidon) wavefunctions. We
contrast various kinds of supersolids in both continuous systems and on
lattices, both condensed matter and cold atom systems. We provide additional
new insights in studying their order parameters, symmetry breaking patterns,
the excitation spectra and detection methods.Comment: REVTEX4, 19 pages, 3 figure
The Periodic Instability of Diameter of ZnO Nanowires via a Self-oscillatory Mechanism
ZnO nanowires with a periodic instability of diameter were successfully prepared by a thermal physical vapor deposition method. The morphology of ZnO nanowires was investigated by SEM. SEM shows ZnO possess periodic bead-like structure. The instability only appears when the diameter of ZnO nanowires is small. The kinetics and mechanism of Instability was discussed at length. The appearance of the instability is due to negative feed-back mechanism under certain experimental conditions (crystallization temperature, vapor supersaturation, etc)
Three chromosome-scale Papaver genomes reveal punctuated patchwork evolution of the morphinan and noscapine biosynthesis pathway
Papaver species P. setigerum, P. rhoeas, and P. somniferum accumulates different levels of morphine and noscapine. Here, the authors report the improved genome assembly of P. somniferum and de novo assembly of the other two species, and reveal the evolution of the benzylisoquinoline alkaloids biosynthetic pathway.For millions of years, plants evolve plenty of structurally diverse secondary metabolites (SM) to support their sessile lifestyles through continuous biochemical pathway innovation. While new genes commonly drive the evolution of plant SM pathway, how a full biosynthetic pathway evolves remains poorly understood. The evolution of pathway involves recruiting new genes along the reaction cascade forwardly, backwardly, or in a patchwork manner. With three chromosome-scale Papaver genome assemblies, we here reveal whole-genome duplications (WGDs) apparently accelerate chromosomal rearrangements with a nonrandom distribution towards SM optimization. A burst of structural variants involving fusions, translocations and duplications within 7.7 million years have assembled nine genes into the benzylisoquinoline alkaloids gene cluster, following a punctuated patchwork model. Biosynthetic gene copies and their total expression matter to morphinan production. Our results demonstrate how new genes have been recruited from a WGD-induced repertoire of unregulated enzymes with promiscuous reactivities to innovate efficient metabolic pathways with spatiotemporal constraint.Computer Science
The energy spectrum of all-particle cosmic rays around the knee region observed with the Tibet-III air-shower array
We have already reported the first result on the all-particle spectrum around
the knee region based on data from 2000 November to 2001 October observed by
the Tibet-III air-shower array. In this paper, we present an updated result
using data set collected in the period from 2000 November through 2004 October
in a wide range over 3 decades between eV and eV, in which
the position of the knee is clearly seen at around 4 PeV. The spectral index is
-2.68 0.02(stat.) below 1PeV, while it is -3.12 0.01(stat.) above 4
PeV in the case of QGSJET+HD model, and various systematic errors are under
study now.Comment: 12 pages, 7 figures, accepted by Advances in space researc
Direct Measurements of Absolute Branching Fractions for D0 and D+ Inclusive Semimuonic Decays
By analyzing about 33 data sample collected at and around 3.773
GeV with the BES-II detector at the BEPC collider, we directly measure the
branching fractions for the neutral and charged inclusive semimuonic decays
to be and , and determine the ratio of the two branching
fractions to be
Moon Shadow by Cosmic Rays under the Influence of Geomagnetic Field and Search for Antiprotons at Multi-TeV Energies
We have observed the shadowing of galactic cosmic ray flux in the direction
of the moon, the so-called moon shadow, using the Tibet-III air shower array
operating at Yangbajing (4300 m a.s.l.) in Tibet since 1999. Almost all cosmic
rays are positively charged; for that reason, they are bent by the geomagnetic
field, thereby shifting the moon shadow westward. The cosmic rays will also
produce an additional shadow in the eastward direction of the moon if cosmic
rays contain negatively charged particles, such as antiprotons, with some
fraction. We selected 1.5 x10^{10} air shower events with energy beyond about 3
TeV from the dataset observed by the Tibet-III air shower array and detected
the moon shadow at level. The center of the moon was detected
in the direction away from the apparent center of the moon by 0.23 to
the west. Based on these data and a full Monte Carlo simulation, we searched
for the existence of the shadow produced by antiprotons at the multi-TeV energy
region. No evidence of the existence of antiprotons was found in this energy
region. We obtained the 90% confidence level upper limit of the flux ratio of
antiprotons to protons as 7% at multi-TeV energies.Comment: 13pages,4figures; Accepted for publication in Astroparticle Physic
Measurement of branching fractions for the inclusive Cabibbo-favored ~K*0(892) and Cabibbo-suppressed K*0(892) decays of neutral and charged D mesons
The branching fractions for the inclusive Cabibbo-favored ~K*0 and
Cabibbo-suppressed K*0 decays of D mesons are measured based on a data sample
of 33 pb-1 collected at and around the center-of-mass energy of 3.773 GeV with
the BES-II detector at the BEPC collider. The branching fractions for the
decays D+(0) -> ~K*0(892)X and D0 -> K*0(892)X are determined to be BF(D0 ->
\~K*0X) = (8.7 +/- 4.0 +/- 1.2)%, BF(D+ -> ~K*0X) = (23.2 +/- 4.5 +/- 3.0)% and
BF(D0 -> K*0X) = (2.8 +/- 1.2 +/- 0.4)%. An upper limit on the branching
fraction at 90% C.L. for the decay D+ -> K*0(892)X is set to be BF(D+ -> K*0X)
< 6.6%
Direct Measurements of the Branching Fractions for and and Determinations of the Form Factors and
The absolute branching fractions for the decays and
are determined using singly
tagged sample from the data collected around 3.773 GeV with the
BES-II detector at the BEPC. In the system recoiling against the singly tagged
meson, events for and events for decays are observed. Those yield
the absolute branching fractions to be and . The
vector form factors are determined to be
and . The ratio of the two form
factors is measured to be .Comment: 6 pages, 5 figure
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