2,167 research outputs found

    Developing predictive insight into changing water systems: use-inspired hydrologic science for the Anthropocene

    Get PDF
    Globally, many different kinds of water resources management issues call for policy- and infrastructure-based responses. Yet responsible decision-making about water resources management raises a fundamental challenge for hydrologists: making predictions about water resources on decadal - to century-long timescales. Obtaining insight into hydrologic futures over 100 yr timescales forces researchers to address internal and exogenous changes in the properties of hydrologic systems. To do this, new hydrologic research must identify, describe and model feedbacks between water and other changing, coupled environmental subsystems. These models must be constrained to yield useful insights, despite the many likely sources of uncertainty in their predictions. Chief among these uncertainties are the impacts of the increasing role of human intervention in the global water cycle – a defining challenge for hydrology in the Anthropocene. Here we present a research agenda that proposes a suite of strategies to address these challenges from the perspectives of hydrologic science research. The research agenda focuses on the development of co-evolutionary hydrologic modeling to explore coupling across systems, and to address the implications of this coupling on the long-time behavior of the coupled systems. Three research directions supportthe development of these models: hydrologic reconstruction, comparative hydrology and model-data learning. These strategies focus on understanding hydrologic processes and feedbacks over long timescales, across many locations, and through strategic coupling of observational and model data in specific systems. We highlight the value of use-inspired and team-based science that is motivated by real-world hydrologic problems but targets improvements in fundamental understanding to support decision-making and management. Fully realizing the potential of this approach will ultimately require detailed integration of social science and physical science understanding of water systems, and is a priority for the developing field of sociohydrology

    The discovery of a five-image lensed quasar at z = 3.34 using PanSTARRS1 and Gaia

    Get PDF
    We report the discovery, spectroscopic confirmation, and mass modelling of the gravitationally lensed quasar system PS J0630-1201. The lens was discovered by matching a photometric quasar catalogue compiled from Pan-STARRS and WISE photometry to the Gaia DR1 catalogue, exploiting the high spatial resolution of the latter (FWHM ∼\sim 0.1") to identify the three brightest components of the lens. Follow-up spectroscopic observations with the WHT confirm the multiple objects are quasars at redshift zq=3.34z_{q}=3.34. Further follow-up with Keck AO high-resolution imaging reveals that the system is composed of two lensing galaxies and the quasar is lensed into a ∼\sim2.8" separation four-image cusp configuration with a fifth image clearly visible, and a 1.0" arc due to the lensed quasar host galaxy. The system is well-modelled with two singular isothermal ellipsoids, reproducing the position of the fifth image. We discuss future prospects for measuring time delays between the images and constraining any offset between mass and light using the faintly detected Einstein arcs associated with the quasar host galaxy

    Pembiayaan murabahah dalam meningkatkan pendapatan operasional PT. Bank Syariah Mandiri KCP Wonocolo Surabaya

    Get PDF
    Penelitian tentang strategi peningkatan pendapatan operasional dilakukan karena kekhuatiran peneliti terhadap implementasi produk pada perbankan syariah. Bank Syariah Mandiri KCP Wonocolo Surabaya mempunyai banyak produk pembiayaan yang menunjang peningkatan pendapatan operasional bank. Produk murabahah pada PT. Bank Syariah Mandiri menjadi produk penyumbang pendapatan opersional tertinggi, padahal dalam teori tidak dijelaskan bahwa pembiayaan murabahah meningkatkan pendapatan opersional. Namun dalam praktek pembiayaan murabahah menjadi penyumbang tertinggi, Hal ini menjadi pertanyaan bagi penulis apakah benar pembiayaan murabahah dapat meningkatkan pendapatan operasional. Peningkatan tersebut tidak akan terjadi dengan sendirinya, tapi mungkin ada faktor lain yang mendukung. Karena itu penelitian ini dilakukan untuk mengkaji kebenaran pembiayaan murabahah dapat meningkatkan pendapatan operasional. Kejadian seperti ini diteliti secara ilmiah dengan penelitian kualitatif untuk mendapat jawaban dan dipertanggungjawabkan. Temuan dalam penelitian ini bahwa pembiayaan murabahah meningkatkan pendapatan operasional karena memang produk tersebut didesain untuk strategi dalam meningkatkan pendapatan operasional. Produk murabahah banyak diminati nasabah, sehingga PT. BankSyariah Mandiri KCP Wonocolo Surabaya menjadikan produk tersebut unggulan. Tidak hanya karena banyak diminati, alasan lain menjadi produk unggulan karena produk murabahah lebih mudah dalam operasionalnya dan pengawasannya. PT. Bank Syariah Mandiri KCP Wonocolo Surabaya tidak perlu ikut campur melakukan usaha nasabah dengan alasan bank tidak menjual barang dan melakukan usaha perbankan sendiri tetapi memberikan jasa peminjaman uang kepada nasabah yang membutuhkan dana. Produk murabahah menjadi produk unggulan, sehingga ada upaya bank untuk melakukan promosi yang berbeda dibandingkan produk lainnya. Dengan melakukan promosi tersebut ada upaya pihak bank menggiring nasabah untuk melakukan pembiayaan murabahah produktif. Setelah nasabah mendapat informasi produk, seharusnya nasabah memilih produk dengan sendirinya berdasarkan edukasi dengan pendampingan petugas. Karena keefektifan murabahah tersebut PT. Bank Syariah Mandiri KCP Wonocolo Surabaya menjadikan murabahah produk unggulan dalam meningkatkan pendapatan

    Telomere erosion in memory T cells induced by telomerase inhibition at the site of antigenic challenge in vivo

    Get PDF
    This work was funded by grants from the Biotechnology and Biological Sciences Research Council Experimental Research on Aging Initiative, Research Into Aging, The Sir Jules Thorne Research Trust, and The Hayward Foundation and Dermatrust

    Investigation of the cutaneous response to recall antigen in humans in vivo.

    Get PDF
    In this paper we provide a detailed description of an experimental method for investigating the induction and resolution of recall immune response to antigen in humans in vivo. This involves the injection of tuberculin purified protein derivative (PPD) into the skin, followed by inducing suction blisters at the site of injection, from which leucocytes and cytokines that are involved in the response can be isolated and characterized. Using this technique we found that although the majority of CD4(+) T cells in the skin that are present early in the response express cutaneous lymphocyte antigen (CLA), the expression of this marker is reduced significantly in later phases. This may enable these cells to leave the skin during immune resolution. Furthermore, interleukin (IL)-2 production can be detected both in CD4(+) T cells and also in the blister fluid at the peak of the response at day 7, indicating that mediators found in the blister fluid are representative of the cytokine microenvironment in vivo. Finally, we found that older humans have defective ability to respond to cutaneous PPD challenge, but this does not reflect a global immune deficit as they have similar numbers of circulating functional PPD-specific CD4(+) T cells as young subjects. The use of the blister technology enables further characterization of the skin specific defect in older humans and also general mechanisms that govern immune regulation in vivo

    Multi-omic data integration elucidates Synechococcus adaptation mechanisms to fluctuations in light intensity and salinity

    Get PDF
    Synechococcus sp. PCC 7002 is a fast-growing cyanobacterium which flourishes in freshwater and marine environments, owing to its ability to tolerate high light intensity and a wide range of salinities. Harnessing the properties of cyanobacteria and understanding their metabolic efficiency has become an imperative goal in recent years owing to their potential to serve as biocatalysts for the production of renewable biofuels. To improve characterisation of metabolic networks, genome-scale models of metabolism can be integrated with multi-omic data to provide a more accurate representation of metabolic capability and refine phenotypic predictions. In this work, a heuristic pipeline is constructed for analysing a genome-scale metabolic model of Synechococcus sp. PCC 7002, which utilises flux balance analysis across multiple layers to observe flux response between conditions across four key pathways. Across various conditions, the detection of significant patterns and mechanisms to cope with fluctuations in light intensity and salinity provides insights into the maintenance of metabolic efficiency

    Massive stars as thermonuclear reactors and their explosions following core collapse

    Full text link
    Nuclear reactions transform atomic nuclei inside stars. This is the process of stellar nucleosynthesis. The basic concepts of determining nuclear reaction rates inside stars are reviewed. How stars manage to burn their fuel so slowly most of the time are also considered. Stellar thermonuclear reactions involving protons in hydrostatic burning are discussed first. Then I discuss triple alpha reactions in the helium burning stage. Carbon and oxygen survive in red giant stars because of the nuclear structure of oxygen and neon. Further nuclear burning of carbon, neon, oxygen and silicon in quiescent conditions are discussed next. In the subsequent core-collapse phase, neutronization due to electron capture from the top of the Fermi sea in a degenerate core takes place. The expected signal of neutrinos from a nearby supernova is calculated. The supernova often explodes inside a dense circumstellar medium, which is established due to the progenitor star losing its outermost envelope in a stellar wind or mass transfer in a binary system. The nature of the circumstellar medium and the ejecta of the supernova and their dynamics are revealed by observations in the optical, IR, radio, and X-ray bands, and I discuss some of these observations and their interpretations.Comment: To be published in " Principles and Perspectives in Cosmochemistry" Lecture Notes on Kodai School on Synthesis of Elements in Stars; ed. by Aruna Goswami & Eswar Reddy, Springer Verlag, 2009. Contains 21 figure

    Stabilizing entanglement autonomously between two superconducting qubits

    Full text link
    Quantum error-correction codes would protect an arbitrary state of a multi-qubit register against decoherence-induced errors, but their implementation is an outstanding challenge for the development of large-scale quantum computers. A first step is to stabilize a non-equilibrium state of a simple quantum system such as a qubit or a cavity mode in the presence of decoherence. Several groups have recently accomplished this goal using measurement-based feedback schemes. A next step is to prepare and stabilize a state of a composite system. Here we demonstrate the stabilization of an entangled Bell state of a quantum register of two superconducting qubits for an arbitrary time. Our result is achieved by an autonomous feedback scheme which combines continuous drives along with a specifically engineered coupling between the two-qubit register and a dissipative reservoir. Similar autonomous feedback techniques have recently been used for qubit reset and the stabilization of a single qubit state, as well as for creating and stabilizing states of multipartite quantum systems. Unlike conventional, measurement-based schemes, an autonomous approach counter-intuitively uses engineered dissipation to fight decoherence, obviating the need for a complicated external feedback loop to correct errors, simplifying implementation. Instead the feedback loop is built into the Hamiltonian such that the steady state of the system in the presence of drives and dissipation is a Bell state, an essential building-block state for quantum information processing. Such autonomous schemes, broadly applicable to a variety of physical systems as demonstrated by a concurrent publication with trapped ion qubits, will be an essential tool for the implementation of quantum-error correction.Comment: 39 pages, 7 figure

    Changes in undergraduate student alcohol consumption as they progress through university

    Get PDF
    BACKGROUND: Unhealthy alcohol use amongst university students is a major public health concern. Although previous studies suggest a raised level of consumption amongst the UK student population there is little consistent information available about the pattern of alcohol consumption as they progress through university. The aim of the current research was to describe drinking patterns of UK full-time undergraduate students as they progress through their degree course. METHOD: Data were collected over three years from 5895 undergraduate students who began their studies in either 2000 or 2001. Longitudinal data (i.e. Years 1–3) were available from 225 students. The remaining 5670 students all responded to at least one of the three surveys (Year 1 n = 2843; Year 2 n = 2219; Year 3 n = 1805). Results: Students reported consuming significantly more units of alcohol per week at Year 1 than at Years 2 or 3 of their degree. Male students reported a higher consumption of units of alcohol than their female peers. When alcohol intake was classified using the Royal College of Physicians guidelines [1] there was no difference between male and females students in terms of the percentage exceeding recommended limits. Compared to those who were low level consumers students who reported drinking above low levels at Year 1 had at least 10 times the odds of continuing to consume above low levels at year 3. Students who reported higher levels of drinking were more likely to report that alcohol had a negative impact on their studies, finances and physical health. Consistent with the reduction in units over time students reported lower levels of negative impact during Year 3 when compared to Year 1. CONCLUSION: The current findings suggest that student alcohol consumption declines over their undergraduate studies; however weekly levels of consumption at Year 3 remain high for a substantial number of students. The persistence of high levels of consumption in a large population of students suggests the need for effective preventative and treatment interventions for all year groups
    • …
    corecore