Причины деградации и перспективы восстановления водно-болотных экосистем Месопотамии

The paper analyzes the main causes of degradation of Mesopotamian Marshlаnds. It is shown that the recovery of the marshland is possible through the combined efforts of several countries involved in the implementation of the UNEP International Plan of the territories rehabilitation, which was taken in 2003.Дан анализ основных причин деградации маршлендов Месопотамии. Показано, что восстановление болот возможно с помощью объединенных усилий нескольких стран, принимающих участие в выполнении Международного плана реабилитации территорий, принятого ЮНЭП в 2003 г

Гидрологические особенности и основные гидротехнические сооружения речной системы Тигр—Евфрат

The article examines the impact of large dams on the river system, describes the peculiarities of hydrology and the largest hydro-technical constructions of the river system, the Tigris-Euphrates.В статье рассматривается влияние строительства крупных плотин на речные системы, описываются особенности гидрологии и наиболее крупных гидротехнических сооружений речной системы Тигр—Евфрат

Positronium Portal into Hidden Sector: A new Experiment to Search for Mirror Dark Matter

The understanding of the origin of dark matter has great importance for cosmology and particle physics. Several interesting extensions of the standard model dealing with solution of this problem motivate the concept of hidden sectors consisting of SU(3)xSU(2)_LxU(1)_Y singlet fields. Among these models, the mirror matter model is certainly one of the most interesting. The model explains the origin of parity violation in weak interactions, it could also explain the baryon asymmetry of the Universe and provide a natural ground for the explanation of dark matter. The mirror matter could have a portal to our world through photon-mirror photon mixing (epsilon). This mixing would lead to orthopositronium (o-Ps) to mirror orthopositronium oscillations, the experimental signature of which is the apparently invisible decay of o-Ps. In this paper, we describe an experiment to search for the decay o-Ps -> invisible in vacuum by using a pulsed slow positron beam and a massive 4pi BGO crystal calorimeter. The developed high efficiency positron tagging system, the low calorimeter energy threshold and high hermiticity allow the expected sensitivity in mixing strength to be epsilon about 10^-9, which is more than one order of magnitude below the current Big Bang Nucleosynthesis limit and in a region of parameter space of great theoretical and phenomenological interest. The vacuum experiment with such sensitivity is particularly timely in light of the recent DAMA/LIBRA observations of the annual modulation signal consistent with a mirror type dark matter interpretation.Comment: 40 pages, 29 Figures 2 Tables v2: Ref. added, Fig. 29 and some text added to explain idea for backscattering e+ background suppression, corrected typos v3: minor corrections: Eq 2.1 corrected (6 lines-> 5 lines), Eq.2.17: two extra "-" signs remove

Understanding the Role of Outsiders in Community-Based Development Interventions

This article analyzes various roles of development practitioners (called outsiders) in five different cases of community-based development (CBD) in rural Iran. It provides a review of the literature on CBD and identifies three main types of roles fulfilled by outsiders to support indigenous development processes. These include preparing the ground, activating community-based organizations as participatory institutions, and taking on the role of brokers who bridge the gap between the local community and outside institutions—especially the state and market. From the analysis of empirical qualitative data collected during fieldwork in Iran, the article concludes that while the roles played by the outsiders in CBD interventions there correspond mostly to those identified in the literature, there are differences in their strategies of intervention and activities under each role which correspond with their contextual contingencies. Recognizing this variation is needed to deepen the understanding of CBD practices and help practitioners think about alternative perspectives and approache

Persistent Spin Currents in Helimagnets

We demonstrate that weak external magnetic fields generate dissipationless spin currents in the ground state of systems with spiral magnetic order. Our conclusions are based on phenomenological considerations and on microscopic mean-field theory calculations for an illustrative toy model. We speculate on possible applications of this effect in spintronic devices.Comment: 9 pages, 6 figures, updated version as published, Journal referenc

Three-body halos. V. Computations of continuum spectra for Borromean nuclei

We solve the coordinate space Faddeev equations in the continuum. We employ hyperspherical coordinates and provide analytical expressions allowing easy computation of the effective potentials at distances much larger than the ranges of the interactions where only s-waves in the different Jacobi coordinates couple. Realistic computations are carried out for the Borromean halo nuclei 6He (n+n+\alpha) for J\pi = 0+-, 1+-, 2+- and 11Li (n+n+9Li) for (1/2)+-, (3/2)+-, (5/2)+-. Ground state properties, strength functions, Coulomb dissociation cross sections, phase shifts, complex S-matrix poles are computed and compared to available experimental data. We find enhancements of the strength functions at low energies and a number of low-lying S-matrix poles.Comment: 35 pages, 14 figure

Epidemiology of facial fractures: Incidence, prevalence and years lived with disability estimates from the Global Burden of Disease 2017 study

Background: The Global Burden of Disease Study (GBD) has historically produced estimates of causes of injury such as falls but not the resulting types of injuries that occur. The objective of this study was to estimate the global incidence, prevalence and years lived with disability (YLDs) due to facial fractures and to estimate the leading injurious causes of facial fracture. Methods: We obtained results from GBD 2017. First, the study estimated the incidence from each injury cause (eg, falls), and then the proportion of each cause that would result in facial fracture being the most disabling injury. Incidence, prevalence and YLDs of facial fractures are then calculated across causes. Results: Globally, in 2017, there were 7 538 663 (95% uncertainty interval 6 116 489 to 9 4