The Forgotten Property Rights: Restrictions on Land Use in Vietnam

Studies of land property rights usually focus on tenure security and transfer rights. Rights to determine how to use the land are regularly ignored. However, in transition economies such as Vietnam and China, user rights are often limited. Relying on a unique Vietnamese panel data set at both household and plot level, we show that crop choice restrictions are widespread and prevent crop diversification. Restrictions do not decrease household income, but restricted households work harder, and there are indications that they are supplied with higher quality inputs. Our findings are consistent with the view that the Vietnamese government has managed to intervene effectively in agricultural (rice) production to promote output and food security. At the same time, it is now time to carefully consider the potential benefits of a more diversified crop pattern.Property rights; restrictions; Vietnam

Critical Behaviour of Non-Equilibrium Phase Transitions to Magnetically Ordered States

We describe non-equilibrium phase transitions in arrays of dynamical systems with cubic nonlinearity driven by multiplicative Gaussian white noise. Depending on the sign of the spatial coupling we observe transitions to ferromagnetic or antiferromagnetic ordered states. We discuss the phase diagram, the order of the transitions, and the critical behaviour. For global coupling we show analytically that the critical exponent of the magnetization exhibits a transition from the value 1/2 to a non-universal behaviour depending on the ratio of noise strength to the magnitude of the spatial coupling.Comment: 4 pages, 5 figure

Template banks to search for compact binaries with spinning components in gravitational wave data

Gravitational waves from coalescing compact binaries are one of the most promising sources for detectors such as LIGO, Virgo and GEO600. If the components of the binary posess significant angular momentum (spin), as is likely to be the case if one component is a black hole, spin-induced precession of a binary's orbital plane causes modulation of the gravitational-wave amplitude and phase. If the templates used in a matched-filter search do not accurately model these effects then the sensitivity, and hence the detection rate, will be reduced. We investigate the ability of several search pipelines to detect gravitational waves from compact binaries with spin. We use the post-Newtonian approximation to model the inspiral phase of the signal and construct two new template banks using the phenomenological waveforms of Buonanno, Chen and Vallisneri. We compare the performance of these template banks to that of banks constructed using the stationary phase approximation to the non-spinning post-Newtonian inspiral waveform currently used by LIGO and Virgo in the search for compact binary coalescence. We find that, at the same false alarm rate, a search pipeline using phenomenological templates is no more effective than a pipeline which uses non-spinning templates. We recommend the continued use of the non-spinning stationary phase template bank until the false alarm rate associated with templates which include spin effects can be substantially reduced.Comment: 11 pages, 3 figure

A Mock Data Challenge for the Einstein Gravitational-Wave Telescope

Einstein Telescope (ET) is conceived to be a third generation gravitational-wave observatory. Its amplitude sensitivity would be a factor ten better than advanced LIGO and Virgo and it could also extend the low-frequency sensitivity down to 1--3 Hz, compared to the 10--20 Hz of advanced detectors. Such an observatory will have the potential to observe a variety of different GW sources, including compact binary systems at cosmological distances. ET's expected reach for binary neutron star (BNS) coalescences is out to redshift $z\simeq 2$ and the rate of detectable BNS coalescences could be as high as one every few tens or hundreds of seconds, each lasting up to several days. %in the sensitive frequency band of ET. With such a signal-rich environment, a key question in data analysis is whether overlapping signals can be discriminated. In this paper we simulate the GW signals from a cosmological population of BNS and ask the following questions: Does this population create a confusion background that limits ET's ability to detect foreground sources? How efficient are current algorithms in discriminating overlapping BNS signals? Is it possible to discern the presence of a population of signals in the data by cross-correlating data from different detectors in the ET observatory? We find that algorithms currently used to analyze LIGO and Virgo data are already powerful enough to detect the sources expected in ET, but new algorithms are required to fully exploit ET data.Comment: accepted for publication in Physical Review D -- 18 pages, 8 figure

Detailed study of null and time-like geodesics in the Alcubierre Warp spacetime

The Alcubierre warp spacetime yields a fascinating chance for comfortable interstellar travel between arbitrary distant places without the time dilation effect as in special relativistic flights. Even though the warp spacetime needs exotic matter for its construction and is thus far from being physically feasible, it offers a rich playground for studying geodesics in the general theory of relativity. This paper is addressed to graduate students who have finished a first course in general relativity to give them a deeper inside in the calculation of non-affinely parametrized null and time-like geodesics and a straightforward approach to determine the gravitational lensing effect due to curved spacetime by means of the Jacobi equation. Both topics are necessary for a thorough discussion of the visual effects as observed by a traveller inside the warp bubble or a person looking from outside. The visual effects of the traveller can be reproduced with an interactive Java application

Comparison of functional outcome after extended versus super-extended pelvic lymph node dissection during radical prostatectomy in high-risk localized prostate cancer

Background: Urinary continence and erectile function (EF) are best preserved whenmeticulous dissection of prostate and nerve sparing technique are used during radicalprostatectomy (RP). However, extent of lymph node dissection (LND) may also adverselyaffect functional results.Objective: To determine whether performing a super-extended LND (seLND) has asignificant effect on recovery of urinary continence and EF after RP.Design, setting, and participants: All patients who underwent RP from January 2007until December 2013 were handed questionnaires assessing continence and EF. Allpatients in whom at least an extended LND (eLND) was performed were selected. Thissearch yielded 526 patients. 172 of these patients had filed out 2 or more questionnairesand were included in our analysis.Outcome measurements and statistical analysis: All questionnaires were reviewed.We used Kaplan–Meier analyses and multivariate Cox analysis to assess the differencein recovery of continence and EF over time for eLND/seLND. Primary endpoints were fullrecovery of continence (no loss of urine) and full recovery of EF (successful intercoursepossible). Patients who did not reach the endpoint when the last questionnaire was filledout were censored at that time. Median follow-up was 12.43 months for continence, and18.97 months for EF.results and limitations: Patients undergoing seLND have a lower chance of regainingboth urinary continence [hazard ratio (HR) 0.59, 95% CI 0.39–0.90, p = 0.026] and EF(HR 0.28, 95% CI 0.13–0.57, p = 0.009). Age at surgery had a significant influence onboth continence and EF in multivariate analysis. Major limitation of the study was that noformal preoperative assessment of continence and potency was done.conclusion: Extending the LND template beyond the eLND template may cause atleast a significant delay in recovery of urinary continence and leads to less recovery of EF.</p

Unanswered questions in prostate cancer : Findings of an international multi-stakeholder consensus by the PIONEER Consortium

Acknowledgements PIONEER is funded through the IMI2 Joint Undertaking and is listed under grant agreement No. 777492. This joint under- taking receives support from the European Union’s Horizon 2020 research and innovation programme and EFPIA.Peer reviewedPostprin