Profile for Aquatic Resources Management: Tboung Kla, Koh Chruem and Ou Chralang villages, Ou Mreah commune, Siem Bouk district, Stung Treng province, Cambodia

This publication is part of a collection of three profiles covering nine aquatic resources-dependent villages in the provinces of Stung Treng, Takeo and Siem Reap. The profiles are important because in most, if not all, of the aquatic-resources villages of Cambodia, critical data and information useful for planning and management are not available in a documented form. The development of the village profiles is viewed as a basic requirement for planning and overall management. It is only an initial step to identify future programs and projects related to aquatic resources. The profiles depict the present state of the villages and their aquatic resources. In general, the villages have limited infrastructure and other physical resources. In the villages of Takeo and Siem Reap, total flooding occurs in the wet season and villagers must rely on transportation by boat. In Stung Treng villages, partial flooding is also a problem as it makes the few existing roads significantly impassable during the wet season.Botanical resources, Resource management, Fishery management, Cambodia,

A new non-Fermi liquid fixed point

We study a new exchange interaction in which the conduction electrons with pseudo spin $S_c=3/2$ interact with the impurity spin $S_I=1/2$. Due to the overscreening of the impurity spin by higher conduction electron spin, a new non-trivial intermediate coupling strength fixed point is realized. Using the numerical renormalization group (NRG), we show that the low-energy spectra are described by a non-Fermi liquid excitation spectrum. A conformal field theory analysis is compared with NRG results and excellent agreement is obtained. Using the double fusion rule to generate the operator spectrum with the conformal theory, we find that the specific heat coefficient and magnetic susceptibility will diverge as $T^{-2/3}$, that the scaling dimension of an applied magnetic field is $5/6$, and that exchange anisotropy is always relevant. We discuss the possible relevance of our work to two-level system Kondo materials and dilute cerium alloys, and we point out a paradox in understanding the Bethe-Ansatz solutions to the multichannel Kondo model.Comment: Revised. 20 page

Tailoring Single and Multiphoton Probabilities of a Single Photon On-Demand Source

As typically implemented, single photon sources cannot be made to produce single photons with high probability, while simultaneously suppressing the probability of yielding two or more photons. Because of this, single photon sources cannot really produce single photons on demand. We describe a multiplexed system that allows the probabilities of producing one and more photons to be adjusted independently, enabling a much better approximation of a source of single photons on demand.Comment: 4 pages, LaTex, 2 figures, twocolumn and RevTex Style for PR

Comparison of BMD changes and bone formation marker levels 3 years after bisphosphonate discontinuation: FLEX and HORIZON-PFT Extension I trials

An ASBMR task force recommends a drug holiday for certain women treated for ≥5 years with oral alendronate or ≥3 years with intravenous zoledronic acid, with reassessment 2-3 years later. It is not known whether changes in BMD or bone turnover markers differ after oral or intravenous therapy. Our goal was to compare changes in BMD and procollagen type I N propeptide, PINP, after oral or intravenous bisphosphonate use. In the Fracture Intervention Trial Long-term Extension (FLEX), women who received a mean 5 years of alendronate were randomized to placebo or continued treatment. In the Health Outcomes and Reduced Incidence with Zoledronic acid Once Yearly-Pivotal Fracture Trial Extension I (HORIZON-PFT E1), women who received 3 years of zoledronic acid were randomized to placebo or continued treatment. We examined the proportion of participants with BMD loss or PINP gain ≥least significant change (LSC), and those whose values exceeded a threshold (T score ≤-2.5 or PINP ≥36.0 ng/mL, a premenopausal median value). After 3 years of placebo, the FLEX group had greater mean total hip BMD decreases (-2.3% versus -1.2% in the HORIZON-PFT E1 group, p < 0.01), and greater rises in PINP (+11.6 ng/mL versus +6.7 ng/mL, p < 0.01). There was a greater proportion of individuals in FLEX with total hip BMD loss and PINP increases that exceeded LSC, and PINP values ≥36.0 ng/mL. In contrast, there were small changes in the proportion of women with femoral neck T scores ≤-2.5 in both groups. In conclusion, 3 years after bisphosphonate discontinuation, a considerable proportion of former alendronate and zoledronic acid users had meaningful declines in total hip BMD and elevations in PINP. Despite a longer treatment course, alendronate may have a more rapid offset of drug effect than zoledronic acid

Two-dimensional limit of exchange-correlation energy functional approximations in density functional theory

We investigate the behavior of three-dimensional (3D) exchange-correlation energy functional approximations of density functional theory in anisotropic systems with two-dimensional (2D) character. Using two simple models, quasi-2D electron gas and two-electron quantum dot, we show a {\it fundamental limitation} of the local density approximation (LDA), and its semi-local extensions, generalized gradient approximation (GGA) and meta-GGA (MGGA), the most widely used forms of which are worse than the LDA in the strong 2D limit. The origin of these shortcomings is in the inability of the local (LDA) and semi-local (GGA/MGGA) approximations to describe systems with 2D character in which the nature of the exchange-correlation hole is very nonlocal. Nonlocal functionals provide an alternative approach, and explicitly the average density approximation (ADA) is shown to be remarkably accurate for the quasi-2D electron gas system. Our study is not only relevant for understanding of the functionals but also practical applications to semiconductor quantum structures and materials such as graphite and metal surfaces. We also comment on the implication of our findings to the practical device simulations based on the (semi-)local density functional method.Comment: 21 pages including 9 figures, to be published in Phys. Rev.

Thermoelectric effects of an Aharonov-Bohm interferometer with an embedded quantum dot in the Kondo regime

Thermoelectric effects are studied in an Aharonov-Bohm (AB) interferometer with an embedded quantum dot in the Kondo regime. The AB flux-dependent transmission probability has an asymmetrical shape arising from the Fano interference between the direct tunneling path and the Kondo-resonant tunneling path through a quantum dot. The sign and magnitude of thermopower can be modulated by the AB flux and the direct tunneling amplitude. In addition, the thermopower is anomalously enhanced by the Kondo correlation in the quantum dot near the Kondo temperature ($T_K$). The Kondo correlation in the quantum dot also leads to crossover behavior in diagonal transport coefficients as a function of temperature. The amplitude of an AB oscillation in electric and thermal conductances is small at temperatures far above $T_K$, but becomes enhanced as the system is cooled below $T_K$. The AB oscillation is strong in the thermopower and Lorenz number within the crossover region near the Kondo temperature.Comment: 16 pages, 10 figure

Prominent bulk pinning effect in the MgB_2 superconductor

We report the magnetic-field dependence of the irreversible magnetization of the recently discovered binary superconductor MgB$_{2}$. For the temperature region of $T< 0.9T_c$, the contribution of the bulk pinning to the magnetization overwhelms that of the surface pinning. This was evident from the fact that the magnetization curves, $M(H)$, were well described by the critical-state model without considering the surface pinning effect. It was also found that the $M(H)$ curves at various temperatures scaled when the field and the magnetization were normalized by the characteristic scaling factors $H^\ast(T)$ and $M^\ast(T)$, respectively. This feature suggests that the pinning mechanism determining the hysteresis in $M(H)$ is unique below $T=T_c$.Comment: 4pages and 4 figures. Phys. Rev. B (accepted

Structural or dispositional? An experimental investigation of the experience of winning in social casino games (and impulsivity) on subsequent gambling behaviors

BACKGROUND AND AIMS: In the present research, we experimentally investigated whether the experience of winning (i.e., inflated payout rates) in a social casino game influenced social casino gamers' subsequent decision to gamble for money. Furthermore, we assessed whether facets of dispositional impulsivity - negative and positive urgency in particular - also influenced participants' subsequent gambling. METHODS: Social casino gamers who were also current gamblers (N = 318) were asked to play a social casino game to assess their perceptions of the game in exchange for $3. Unbeknownst to them, players were randomly assigned to one of three experimental conditions: winning (n = 110), break-even (n = 103), or losing (n = 105). After playing, participants were offered a chance to gamble their$3 renumeration in an online roulette game. RESULTS: A total of 280 participants (88.1%) elected to gamble, but no between-condition variation in the decision to gamble emerged. Furthermore, there were no differences in gambling on the online roulette between condition. However, higher levels of both negative and positive urgency increased the likelihood of gambling. Finally, impulsivity did not moderate the re

Charge order and low frequency spin dynamics in lanthanum cuprates revealed by Nuclear Magnetic Resonance

We report detailed 17O, 139La, and 63Cu Nuclear Magnetic Resonance (NMR) and Nuclear Quadrupole Resonance (NQR) measurements in a stripe ordered La1.875Ba0.125CuO4 single crystal and in oriented powder samples of La1.8-xEu0.2SrxCuO4. We observe a partial wipeout of the 17O NMR intensity and a simultaneous drop of the 17O electric field gradient (EFG) at low temperatures where the spin stripe order sets in. In contrast, the 63Cu intensity is completely wiped out at the same temperature. The drop of the 17O quadrupole frequency is compatible with a charge stripe order. The 17O spin lattice relaxation rate shows a peak similar to that of the 139La, which is of magnetic origin. This peak is doping dependent and is maximal at x ~ 1/8.Comment: submitted to European Physical Journal Special Topic