Young measures in a nonlocal phase transition problem

A nonlocal variational problem modelling phase transitions is studied in the framework of Young measures. The existence of global minimisers among functions with internal layers on an infinite tube is proved by combining a weak convergence result for Young measures and the principle of concentration-compactness. The regularity of such global minimisers is discussed, and the nonlocal variational problem is also considered on asymptotic tubes

El curso superior del río más grande del sur de china como un «frente evolutivo» de plantas tropicales: evidencia del género endémico de Asia Hiptage (Malpighiaceae)

The biodiversity hotspot at the Guizhou–Yunnan–Guangxi borders is a distribution centre of tropical plants in China. It spans the whole upper reaches of Zhujiang River, the largest river in Southern China. In this paper, I aimed to explore the roles of the river in the spread and diversification of tropical plants in this area, using the Asia-endemic genus Hiptage Gaertn. (Malpighiaceae) as an example. Two diversity and endemism centres of Hiptage are recognized: Indo-China Peninsula and upper reaches of Zhujiang River (UZJ). The area-adjusted endemism index further indicates UZJ as the most important distribution region of endemic species since UZJ has a very small area (~210,000 km2) but six out of the total seven species are narrow endemics. UZJ is located at the northern edge of distribution ranges of Hiptage, which resulted mainly from the north-west–south-east river systems of UZJ promoting northward spreads of this tropical genus. The highly-fragmented limestone landscapes in this region may promote habitat isolation and tends to be the main driving factor for origins of these endemic species. Hiptage is also distinctive for its highly-specialized pollination system, mirror-image flowers, which probably facilitates species diversification via floral and pollination isolation. Other studies also found UZJ as a major diversification centre of the tropical plant families Gesneriaceae and Begoniaceae. Thereafter, it is concluded that UZJ is an “evolutionary front” of tropical plants in China, which contributes significantly to the origin and maintenance of the unique biodiversity in the area.El hotspot de biodiversidad en las fronteras de las provincias Guizhou-Yunnan- Guangxi es un centro de distribución de plantas tropicales en China. Se extiende por toda la cuenca alta del río Zhujiang, el mayor río del sur de China. En este artículo, se explora el papel del río en la propagación y la diversificación de las plantas tropicales en este área, usando el género endémico de Asia Hiptage Gaertn. (Malpighiaceae) como ejemplo. Se reconocen dos centros de diversidad y endemismo de Hiptage: la Península Indochina y el curso superior del río Zhujiang (UZJ). El índice de endemismo ajustado al área indica UZJ como la región más importante de distribución de especies endémicas, ya que, aunque UZJ tiene un área muy pequeña (~210.000 km2), seis de un total de siete especies son estrictamente endémicas. UZJ está situado en el extremo norte del área de distribución de Hiptage, lo que resultó principalmente de la disposición noroeste-sureste de los sistemas fluviales de UZJ, que facilitaron la expansión y diferenciación hacia el norte de este género tropical. Los paisajes de piedra caliza altamente fragmentados en esta región han contribuido al aislamiento de hábitat y pueden ser el principal factor para el origen de estas especies endémicas. Hiptage también se distingue por su sistema de polinización altamente especializado, con flores de imagen especular, lo que probablemente facilita la diversificación de las especies a través del aislamiento de la polinización. Otros estudios también encontraron que UZJ es un importante centro de diversificación de las familias de plantas tropicales Begoniaceae y Gesneriaceae. Por consiguiente, se concluye que UZJ es un «frente evolutivo» de plantas tropicales en China, lo que contribuye de manera significativa al origen y mantenimiento de la biodiversidad única en la zona

Privacy-Preserving Outsourcing of Large-Scale Nonlinear Programming to the Cloud

The increasing massive data generated by various sources has given birth to big data analytics. Solving large-scale nonlinear programming problems (NLPs) is one important big data analytics task that has applications in many domains such as transport and logistics. However, NLPs are usually too computationally expensive for resource-constrained users. Fortunately, cloud computing provides an alternative and economical service for resource-constrained users to outsource their computation tasks to the cloud. However, one major concern with outsourcing NLPs is the leakage of user's private information contained in NLP formulations and results. Although much work has been done on privacy-preserving outsourcing of computation tasks, little attention has been paid to NLPs. In this paper, we for the first time investigate secure outsourcing of general large-scale NLPs with nonlinear constraints. A secure and efficient transformation scheme at the user side is proposed to protect user's private information; at the cloud side, generalized reduced gradient method is applied to effectively solve the transformed large-scale NLPs. The proposed protocol is implemented on a cloud computing testbed. Experimental evaluations demonstrate that significant time can be saved for users and the proposed mechanism has the potential for practical use.Comment: Ang Li and Wei Du equally contributed to this work. This work was done when Wei Du was at the University of Arkansas. 2018 EAI International Conference on Security and Privacy in Communication Networks (SecureComm

Exploring the random phase approximation: Application to CO adsorbed on Cu(111)

The adsorption of CO on the Cu(111) surface is investigated in the random phase approximation (RPA) as formulated within the adiabatic connection fluctuation-dissipation theorem. The RPA adsorption energy is obtained by adding a "local exchange-correlation correction" that is extrapolated from cluster calculations of increasing size, to the Perdew-Burke-Ernzerhof (PBE) value for the extended system. In comparison to density-functional theory calculations with the generalized gradient functionals PBE and AM05 and the hybrid functionals PBE0 and HSE03, we find a hierarchy of improved performance from AM05/PBE to PBE0/HSE03, and from PBE0/HSE03 to RPA, both in terms of the absolute adsorption energy as well as the adsorptionenergy difference between the atop and the hollow fcc sites. In particular, the very weak atop site preference at the PBE0/HSE03 level is further stabilized by about 0.2 eV in the RPA. The mechanism behind this improvement is analyzed in terms of the GW density of states that gives a spectral representation en par with the RPA formalism for the total energy

Patrones de distribución de individuos longevos de plantas relictas en los alrededores de la montana Fanjingshan en China: implicaciones para su conservación in situ

The mountain areas in south-central China are widely recognized as refugia of relict plants during the late Neogene and Quaternary periods. In this paper, we try to explore the distribution patterns of natural habitats and to exactly locate the refugia of relict species around Fanjingshan Mountain using dendrological data of long-lived individuals (≥ 100 years old). Six typical relict plants were found around the mountain, i.e. Cyclocarya paliurus, Ginkgo biloba, Liriodendron chinense, Pinus massoniana, Podocarpus macrophyllus, and Taxus chinensis. The long-lived individuals were divided into three classes according to their ages: Class-I (≥ 500 years), Class-II (300–499 years), and Class-III (100–299 years). Our results showed that the south-west region to the mountain was the main distribution area of Class-I trees of G. biloba and T. chinensis, most of which occurring in the same small village (Yangliu Village of Yinjiang County). The north-east region harboured all the six relict species. Floristic analyses also indicated these two regions were very similar in tree growth as measured by DBH (diameter at breast height of 1.3 m). Thus, these two areas would have provided long-term suitable habitats for relict species. The south-west region, especially the small village Yangliu, should be given highest priority for in situ conservation of relict species and other rare and endangered plants. Attention should also be paid to the north-east region for its very high species diversity of relict species.Las áreas montañosas de la región centro-sur de China están ampliamente reconocidas por su papel como refugio de plantas relictas durante la última etapa del Neógeno y el Cuaternario. En el presente trabajo se intentan explorar los patrones de distribución de los hábitats naturales y la localización exacta de los refugios para especies vegetales relictas en los alrededores de la montaña Fanjinshan, mediante el empleo de datos dendrológicos de individuos longevos (≥ 100 años). En el área de estudio se encontraron seis especies vegetales típicamente relictas: Cyclocarya paliurus, Ginkgo biloba, Liriodendron chinense, Pinus massoniana, Podocarpus macrophyllus y Taxus chinensis. Los individuos longevos se dividieron en tres categorías de acuerdo con su edad estimada: individuos de Clase I (≥ 500 años), de Clase II (300–499 años) y de Clase III (100–299 años). Nuestros resultados muestran que la región situada al suroeste de la montaña se corresponde con la principal área de distribución de los árboles de Clase I de G. biloba y T. chinensis, localizándose la mayor parte de éstos en los alrededores de una pequeña aldea (Yangliu, en el condado de Yinjiang). La región situada al noreste de Fanjinshan alberga, por su parte, las seis especies relictas, y los análisis florísticos muestran una elevada similaridad entre ambas regiones por lo que respecta al crecimiento arbóreo medido como DBH [diámetro a la altura del pecho (1,3 m)]. Por consiguiente, estas dos regiones habrían proporcionado hábitats adecuados para la supervivencia de especies relictas. La región suroeste, y en especial la aldea de Yangliu, deben recibir la máxima prioridad para la conservación in situ de especies relictas (y otras especies raras y amenazadas). La región noreste también debe priorizarse dada su elevada diversidad de especies relictas

Performance of Photosensors in the PandaX-I Experiment

We report the long term performance of the photosensors, 143 one-inch R8520-406 and 37 three-inch R11410-MOD photomultipliers from Hamamatsu, in the first phase of the PandaX dual-phase xenon dark matter experiment. This is the first time that a significant number of R11410 photomultiplier tubes were operated in liquid xenon for an extended period, providing important guidance to the future large xenon-based dark matter experiments.Comment: v3 as accepted by JINST with modifications based on reviewers' comment

Dynamics of a suspension of interacting yolk-shell particles

In this work we study the self-diffusion properties of a liquid of hollow spherical particles (shells)bearing a smaller solid sphere in their interior (yolks). We model this system using purely repulsive hard-body interactions between all (shell and yolk) particles, but assume the presence of a background ideal solvent such that all the particles execute free Brownian motion between collisions,characterized by short-time self-diffusion coefficients D0s for the shells and D0y for the yolks. Using a softened version of these interparticle potentials we perform Brownian dynamics simulations to determine the mean squared displacement and intermediate scattering function of the yolk-shell complex. These results can be understood in terms of a set of effective Langevin equations for the N interacting shell particles, pre-averaged over the yolks' degrees of freedom, from which an approximate self-consistent description of the simulated self-diffusion properties can be derived. Here we compare the theoretical and simulated results between them, and with the results for the same system in the absence of yolks. We find that the yolks, which have no effect on the shell-shell static structure, influence the dynamic properties in a predictable manner, fully captured by the theory.Comment: 5 pages, 1 figur

Analysis of Controlling Genes for Tiller Growth of \u3cem\u3ePsathyrostachys juncea\u3c/em\u3e Based on Transcriptome Sequencing Technology

Tillering is an important trait of bunch grass that affects biomass and seed yield. Psathyrostachys juncea is a typical perennial bunch grass, and unraveling the regulatory mechanisms of tillering in P. juncea could be helpful to improve the yield of perennial gramineous forages. Hence, we selected the tiller node of P. juncea for transcriptome sequencing to determine the differentially expressed genes (DEG) between high and low tillering materials. The metabolic pathway was studied，candidate genes were screened, and reference genes stability were evaluated. The results showed that approximately 5466 DEGs were identified between two P. juncea genotypes that significantly differed in tiller number. Pathway enrichment analysis indicated that DEGs related to the biosynthesis of three classes of phytohormones, i.e., strigolactones (SLs), auxin (IAA), and cytokinin (CTK), as well as “nitrogen metabolism” and “biosynthesis of lignin” dominated the differences between the dense and sparse tillering genotypes. Meanwhile, the reference gene Actin1, having with the best stability, was screened from twelve highest expression level genes and was used in verification of ten tillering candidate genes. The candidate genes revealed in our research are involved in the regulation of tillering in perennial grasses and are available for new breeding resources establishment for high-yield perennial grasses