Application of cover-free codes and combinatorial designs to two-stage testing

AbstractWe study combinatorial and probabilistic properties of cover-free codes and block designs which are useful for their efficient application as the first stage of two-stage group testing procedures. Particular attention is paid to these procedures because of their importance in such applications as monoclonal antibody generation and cDNA library screening

Geochemical evidence of denitrification in the Benguela upwelling system

This paper presents analysis of nitrate, phosphate and silicate data from the Benguela upwelling system. Evidence is presented that suggests denitrification occurring close to shore, and also nutrient trapping. Denitrification leaves an imprint on the water properties in terms of a nitrate deficit, that is to say nitrate concentrations that are significantly less than predicted by multiplying the phosphate concentrations by the Redfield ratio. It is probable that denitrification also causes a decoupling of nitrate and carbon compared to Redfield processes, and large-scale losses of nitrate in the Benguela which are not accompanied by losses of carbon. Nitrate-driven CO2 drawdown following upwelling will be less than it might otherwise be, because of denitrification. Nutrient trapping (secondary remineralisation) is apparent as enhanced phosphate concentrations, some of which are several Full-size image (<1 K) higher than in the offshore source waters for upwelling. Waters also become enriched in silicate and to a lesser extent nitrate as they advect across the shelf. By implication the same process should also “supercharge” waters in dissolved inorganic carbon, leading to stronger outgassing of CO2 immediately after upwelling. The effect is again to increase the size of the estimated Benguela upwelling system CO2 source

A Big Fan of Signals? Exploring Autogenic and Allogenic Process and Product In a Numerical Stratigraphic Forward Model of Submarine-Fan Development

Distinguishing an allogenic signal from trends and patterns produced by autogenic processes is a critical element in interpreting, understanding, and predicting strata. Lobyte3D is a new reduced-complexity model of dispersive flow over an evolving topography on fan systems that produces surprisingly complex potentially hierarchical strata despite a simple formulation. Two submarine-fan model scenarios are run, one with constant sediment input, and one with a sinusoidal variation in sediment input with an oscillation period of 25 ky and a peak-to-trough 80% volume change. Both model scenarios show that flows cluster to produce lobes which migrate and can rapidly switch location. Runs tests that can detect thickening and thinning bed trends and spectral analysis that detects the frequency of any signal present suggest that strata can be ordered even in the absence of any allogenic signal, with cycles and trends in bed thickness, but no single characteristic frequency. In the oscillating-supply scenario, an allogenic signal is present in places, particularly in the axial mid fan, but may be difficult to distinguish from the autogenic signal with only limited outcrop data, and without knowing a priori how the allogenic signal is likely to be preserved in complex and incomplete strata. Based on these limited model results we hypothesize that analysis of mid-fan vertical sections, using simple power-spectrum analysis and counting of the significant peaks present across a range of frequencies, may allow identification of a “signal bump” that could be evidence of the presence and nature of allocyclic forcing. Further Lobyte3D modeling work will explore if and how the “signal bump” is preserved with input signals across a range of frequencies and amplitudes, to guide further data collection and interpretation in outcrop and subsurface strata

On the dimension of subspaces with bounded Schmidt rank

We consider the question of how large a subspace of a given bipartite quantum system can be when the subspace contains only highly entangled states. This is motivated in part by results of Hayden et al., which show that in large d x d--dimensional systems there exist random subspaces of dimension almost d^2, all of whose states have entropy of entanglement at least log d - O(1). It is also related to results due to Parthasarathy on the dimension of completely entangled subspaces, which have connections with the construction of unextendible product bases. Here we take as entanglement measure the Schmidt rank, and determine, for every pair of local dimensions dA and dB, and every r, the largest dimension of a subspace consisting only of entangled states of Schmidt rank r or larger. This exact answer is a significant improvement on the best bounds that can be obtained using random subspace techniques. We also determine the converse: the largest dimension of a subspace with an upper bound on the Schmidt rank. Finally, we discuss the question of subspaces containing only states with Schmidt equal to r.Comment: 4 pages, REVTeX4 forma

Unprecedented 21st century drought risk in the American Southwest and Central Plains

In the Southwest and Central Plains of Western North America, climate change is expected to increase drought severity in the coming decades. These regions nevertheless experienced extended Medieval-era droughts that were more persistent than any historical event, providing crucial targets in the paleoclimate record for benchmarking the severity of future drought risks. We use an empirical drought reconstruction and three soil moisture metrics from 17 state-of-the-art general circulation models to show that these models project significantly drier conditions in the later half of the 21st century compared to the 20th century and earlier paleoclimatic intervals. This desiccation is consistent across most of the models and moisture balance variables, indicating a coherent and robust drying response to warming despite the diversity of models and metrics analyzed. Notably, future drought risk will likely exceed even the driest centuries of the Medieval Climate Anomaly (1100–1300 CE) in both moderate (RCP 4.5) and high (RCP 8.5) future emissions scenarios, leading to unprecedented drought conditions during the last millennium

HST Studies of the WLM Galaxy. I. The Age and Metallicity of the Globular Cluster

We have obtained V and I images of the lone globular cluster that belongs to the dwarf Local Group irregular galaxy known as WLM. The color-magnitude diagram of the cluster shows that it is a normal old globular cluster with a well-defined giant branch reaching to M_V=-2.5, a horizontal branch at M_V=+0.5, and a sub-giant branch extending to our photometry limit of M_V=+2.0. A best fit to theoretical isochrones indicates that this cluster has a metallicity of [Fe/H]=-1.52\pm0.08 and an age of 14.8\pm0.6 Gyr, thus indicating that it is similar to normal old halo globulars in our Galaxy. From the fit we also find that the distance modulus of the cluster is 24.73\pm0.07 and the extinction is A_V=0.07\pm0.06, both values that agree within the errors with data obtained for the galaxy itself by others. We conclude that this normal massive cluster was able to form during the formation of WLM, despite the parent galaxy's very small intrinsic mass and size.Comment: 14 pages, 5 figures, 1 tabl

UJI EFEK ANTI DIABETES EKSTRAK ETANOL DAUN KELOR (Moringa oleifera) TERHADAP TIKUS PUTIH SPRAGUE DAWLEY YANG DIINDUKSI ALOKSAN

Diabetes Melitus (DM) adalah gangguan metabolik yang terjadi secara kronik atau menahun akibat kelainan dari produksi dan sifat insulin atau keduanya yang menyebabkan berbagai komplikasi kesehatan. Hal ini mengakibatkan peningkatan kadar glukosa darah diatas nilai normal atau hiperglikemia.&nbsp; Angka kejadian DM di dunia pada tahun 2017&nbsp; berjumlah 424,9 juta jiwa, sedangkan di Indonesia berjumlah 10,3 juta jiwa yang menepati peringkat ke enam didunia dan provinsi NTT menepati peringkat ke empat di Indonesia. Pada daun kelor (Moringa oleifera) terkandung antioksidan flavonoid yang memiliki fungsi untuk meningkatkan sekresi insulin dan meningkatkan ambilan glukosa. Tujuan penelitian ini untuk mengetahui ada tidaknya efek antidiabetika eksrak etanol daun kelor&nbsp; (Moringa oleifera)&nbsp; terhadap tikus putih Sprague dawley yang diinduksi aloksan. Metode penelititan eksperimental dengan desain true experimental-randomized pretest and post test with control group. Sampel penelitian berjumlah 24 ekor tikus jantan dipilih secara acak ke dalam beberapa kelompok yaitu kontrol normal (tidak diberikan perlakuan), kontrol negatif (diberikan Na-CMC 0,5%),kontrol positif (diberikan glibenklamid 5 mg/kgBB) dan tiga kelompok perlakuan ekstrak yaitu dosis 1 (250 mg/kgBB), dosis 2 (450 mg/kgBB) dan dosis 3 (600 mg/kgBB). Berikutnya dilakukan pre-test untuk mengetahui keadaan awal sampel, kemudian dilanjutkan dengan post-test untuk melihat pengaruh pemberian perlakuan tersebut. Hasil ekstrak daun kelor (Moringa oleifera) dalam semua dosis memiliki nilai probabilitas &lt;0,05 yang menunjukan penurunan kadar gula darah yang signifikan secara statistik. Kesimpulan dari penelitian ini didapat Ekstrak daun kelor (Moringa oleifera) memiliki efek anti diabeti

Intercomparison of carbonate chemistry measurements on a cruise in northwestern European shelf seas

Four carbonate system variables were measured in surface waters during a cruise aimed at investigating ocean acidification impacts traversing northwestern European shelf seas in the summer of 2011. High-resolution surface water data were collected for partial pressure of carbon dioxide (pCO2; using two independent instruments) and pH using the total pH scale (pHT), in addition to discrete measurements of total alkalinity and dissolved inorganic carbon. We thus overdetermined the carbonate system (four measured variables, two degrees of freedom), which allowed us to evaluate the level of agreement between the variables on a cruise whose main aim was not intercomparison, and thus where conditions were more representative of normal working conditions. Calculations of carbonate system variables from other measurements generally compared well with direct observations of the same variables (Pearson’s correlation coefficient always greater than or equal to 0.94; mean residuals were similar to the respective accuracies of the measurements). We therefore conclude that four of the independent data sets of carbonate chemistry variables were of high quality. A diurnal cycle with a maximum amplitude of 41 μatm was observed in the difference between the pCO2 values obtained by the two independent analytical pCO2 systems, and this was partly attributed to irregular seawater flows to the equilibrator and partly to biological activity inside the seawater supply and one of the equilibrators. We discuss how these issues can be addressed to improve carbonate chemistry data quality on future research cruises