6,938 research outputs found
Effects of land incremental value allocation on rural operational construction land (ROCL) under market mechanism: case study in China
The use of the market mechanism to convert the rural operational construction land (ROCL) into urban construction land without ownership changes is currently being introduced into reform pilot projects in China, changing the only form of governmental expropriation in the past. The new system allows rural collective economic organizations and members of the rural collective economy to directly participate in the allocation of land incremental value increases due to changes in land use. This replaces the previous way of allocating only the original use compensation from the government. This paper investigates the collectively owned new system, to establish the positive effects and shortcoming of the new model. Three cases are applied for the analysis using inductive-deductive reasoning methodology based on the property right and landrent theories. We have found that local government land adjustment charges on the transactions of rural construction land are suggested to be from 16 to 20 percent. The share ownership quantification model (SOQM) of land incremental value allocation between the collective economic organizations and members is effective and beneficial to the development of the rural collective economy and its members
Longitudinal Schottky spectra of a bunched Ne10+ ion beam at the CSRe
The longitudinal Schottky spectra of a radio-frequency (RF) bunched and
electron cooled 22Ne10+ ion beam at 70 MeV/u have been studied by a newly
installed resonant Schottky pick-up at the experimental cooler storage ring
(CSRe), at IMP. For an RF-bunched ion beam, a longitudinal momentum spread of
has been reached with less than 107 stored ions. The reduction of momentum
spread compared with coasting ion beam was observed from Schottky noise signal
of the bunched ion beam. In order to prepare the future laser cooling
experiment at the CSRe, the RF-bunching power was modulated at 25th, 50th and
75th harmonic of the revolution frequency, effective bunching amplitudes were
extracted from the Schottky spectrum analysis. Applications of Schottky noise
for measuring beam lifetime with ultra-low intensity of ion beams are
presented, and it is relevant to upcoming experiments on laser cooling of
relativistic heavy ion beams and nuclear physics at the CSRe.Comment: to be published in Chinese Physics
Descending motor circuitry required for NT-3 mediated locomotor recovery after spinal cord injury in mice
Locomotor function, mediated by lumbar neural circuitry, is modulated by descending spinal pathways. Spinal cord injury (SCI) interrupts descending projections and denervates lumbar motor neurons (MNs). We previously reported that retrogradely transported neurotrophin-3 (NT-3) to lumbar MNs attenuated SCI-induced lumbar MN dendritic atrophy and enabled functional recovery after a rostral thoracic contusion. Here we functionally dissected the role of descending neural pathways in response to NT-3-mediated recovery after a T9 contusive SCI in mice. We find that residual projections to lumbar MNs are required to produce leg movements after SCI. Next, we show that the spared descending propriospinal pathway, rather than other pathways (including the corticospinal, rubrospinal, serotonergic, and dopaminergic pathways), accounts for NT-3-enhanced recovery. Lastly, we show that NT-3 induced propriospino-MN circuit reorganization after the T9 contusion via promotion of dendritic regrowth rather than prevention of dendritic atrophy
Emergence of non-centrosymmetric topological insulating phase in BiTeI under pressure
The spin-orbit interaction affects the electronic structure of solids in
various ways. Topological insulators are one example where the spin-orbit
interaction leads the bulk bands to have a non-trivial topology, observable as
gapless surface or edge states. Another example is the Rashba effect, which
lifts the electron-spin degeneracy as a consequence of spin-orbit interaction
under broken inversion symmetry. It is of particular importance to know how
these two effects, i.e. the non-trivial topology of electronic states and
Rashba spin splitting, interplay with each other. Here we show, through
sophisticated first-principles calculations, that BiTeI, a giant bulk Rashba
semiconductor, turns into a topological insulator under a reasonable pressure.
This material is shown to exhibit several unique features such as, a highly
pressure-tunable giant Rashba spin splitting, an unusual pressure-induced
quantum phase transition, and more importantly the formation of strikingly
different Dirac surface states at opposite sides of the material.Comment: 5 figures are include
Syphilis-attributable adverse pregnancy outcomes in China: a retrospective cohort analysis of 1187 pregnant women with different syphilis treatment.
BACKGROUND: Syphilis is responsible for a substantial burden of preventable adverse outcomes in pregnancy. The purpose of this study was to compare the frequency of adverse pregnancy outcomes among syphilis-seropositive women who received different treatment regimens at different times in Guangzhou, China. METHODS: Pregnant women with syphilis infection who received prenatal and delivery services in Guangzhou between January 2014 and December 2016 were included. Association between treatment status and the composite adverse outcomes (preterm birth, infant smaller than gestational age, stillbirth, and spontaneous abortion) was estimated. RESULTS: Of 1187 syphilis-seropositive pregnant women included in the analysis, 900 (75.8%) syphilis-seropositive pregnant women received treatment, and 287(24.2%) did not receive treatment. Adverse pregnancy outcomes were observed among 16.3% (147/900) of women with treatment and 33.8% (97/287) of women without treatment. Syphilis-seropositive pregnant women treated with one or two courses of penicillin had a similar risk of adverse pregnancy outcomes (adjusted RR = 1.36, 95% CI: 0.94-1.96). Adverse outcomes were more common among women whose non-treponemal serum test titer was >1:8 and received treatment after 28 weeks compared to before 28 weeks (adjusted RR = 2.34, 95% CI: 1.22-4.48). CONCLUSIONS: Women who received one course of penicillin and women who received two courses of penicillin had a similar risk of adverse pregnancy outcomes. Syphilis treatment before 28 weeks of pregnancy is critical. Strategies to promote high-quality prenatal services are needed
Study of and and
We study the decays of and to the final states
and based on a single
baryon tag method using data samples of
and events collected with
the BESIII detector at the BEPCII collider. The decays to
are observed for the first time. The
measured branching fractions of and
are in good agreement with, and much
more precise, than the previously published results. The angular parameters for
these decays are also measured for the first time. The measured angular decay
parameter for , , is found to be negative, different to the other
decay processes in this measurement. In addition, the "12\% rule" and isospin
symmetry in the and and
systems are tested.Comment: 11 pages, 7 figures. This version is consistent with paper published
in Phys.Lett. B770 (2017) 217-22
Observation of an anomalous line shape of the mass spectrum near the mass threshold in
Using events collected by the BESIII experiment
in 2012, we study the
process and observe a significant abrupt change in the slope of the
invariant mass distribution at the
proton-antiproton () mass threshold. We use two models to
characterize the line shape around
: one which explicitly incorporates the opening of a
decay threshold in the mass spectrum (Flatt\'{e} formula), and another which is
the coherent sum of two resonant amplitudes. Both fits show almost equally good
agreement with data, and suggest the existence of either a broad state around
with strong couplings to final states or a
narrow state just below the mass threshold. Although we cannot
distinguish between the fits, either one supports the existence of a
molecule-like state or bound state with greater than significance
Measurements of absolute hadronic branching fractions of baryon
Using of collisions recorded at
with the BESIII detector, we report first measurements
of absolute hadronic branching fractions of Cabibbo-favored decays of the
baryon with a double-tag technique. A global least-square
fitter is utilized to improve the measured precision. Among the measurements
for twelve decay modes, the branching fraction for
is determined to be
, where the first uncertainty is statistical and the
second is systematic. In addition, the measurements of the branching fractions
of the other eleven Cabbibo-favored hadronic decay modes are significantly
improved
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