A Multivariate Water Quality Investigation of Select Drainage Ditches in the Arroyo Colorado River Watershed, Texas

Drainage ditches are widely used for agricultural water management to help remove excess water from fields, which mitigates the effects of water logging and salinization. These ditches act as a direct hydraulic link between the agricultural field and streams and rivers. As such, there is an increasing concern that drainage ditches can act as conduits for nutrient transport and, in conjunction with other point and nonpoint sources, can contribute to eutrophication and decreased dissolved oxygen levels in receiving water bodies. Studies have linked drainage ditches to hypoxia in the Gulf of Mexico and eutrophication of the Great Lakes (Dagg and Breed, 2003; Moore et al., 2010). However, there is also evidence suggesting that drainage ditches can help attenuate the loadings of phosphorus and suspended sediments (R. Kröger et al., 2008) and thus foster water quality improvements at a watershed scale. There is a growing interest in understanding the nutrient behavior in drainage ditches both in the United States (Bhattarai et al. 2009; Moore, et al. 2010; Ahiablame et al. 2011) as well as other parts of the world (Nguyen and Sukias 2002; Leone et al. 2008; Bonaiti and Borin 2010)

Role of Dental Adult Stem Cells in Regenerative Medicine

Statement of problem: Stem cell biology is today one of the most exciting field of research with promising possibilities in all spheres of medical and dental science. Erupting tooth and its allied structures have emerged as a valuable source of adult stem cells. A lot of research is going on around the world in the field of regenerative medicine with the help of adult dental stem cells, but a comprehensive review is missing. Purpose: This article provides an overview of different types of adult stem cells that have been isolated from teeth, includingdental pulp stem cells (DPSCs), stem cells from human exfoliated deciduous teeth (SHEDs), periodontal ligament stem cells (PDLSCs), dental follicle progenitor stem cells (DFPCs),and stem cells from apical papilla (SCAPs) with their use in regenerative medicine. Materials and methods: The literature was acquired in a systematic search of the titles–DPSC, SHED, PDLSC, DFPC and SCAP on PubMed. Articles dealing with only regenerative medicine and in English language were selected for review. Results: A total of 1,211 articles were found on PubMed. The articles were then shortlisted according to the set criteria and a total of 53 articles were selected and the review was prepared. Conclusion: Dental adult stem cells have proved themselves to be of vast future use. Research has shown that these cells can differentiate into variety of cells, e.g. smooth muscle cells, adipocytes, chondrocytes, and neurons, etc. A cautious and systematic approach still needs to be adopted in embracing this technology

Multiplexed Predictive Control of a Large Commercial Turbofan Engine

Model predictive control is a strategy well-suited to handle the highly complex, nonlinear, uncertain, and constrained dynamics involved in aircraft engine control problems. However, it has thus far been infeasible to implement model predictive control in engine control applications, because of the combination of model complexity and the time allotted for the control update calculation. In this paper, a multiplexed implementation is proposed that dramatically reduces the computational burden of the quadratic programming optimization that must be solved online as part of the model-predictive-control algorithm. Actuator updates are calculated sequentially and cyclically in a multiplexed implementation, as opposed to the simultaneous optimization taking place in conventional model predictive control. Theoretical aspects are discussed based on a nominal model, and actual computational savings are demonstrated using a realistic commercial engine model

Tailoring Threshold Voltages of Printed Electrolyte-Gated Field-Effect Transistors by Chromium Doping of Indium Oxide Channels

Printed systems spark immense interest in industry, and for several parts such as solar cells or radio frequency identification antennas, printed products are already available on the market. This has led to intense research; however, printed field-effect transistors (FETs) and logics derived thereof still have not been sufficiently developed to be adapted by industry. Among others, one of the reasons for this is the lack of control of the threshold voltage during production. In this work, we show an approach to adjust the threshold voltage (V$_{th}$) in printed electrolyte-gated FETs (EGFETs) with high accuracy by doping indium-oxide semiconducting channels with chromium. Despite high doping concentrations achieved by a wet chemical process during precursor ink preparation, good on/off-ratios of more than five orders of magnitude could be demonstrated. The synthesis process is simple, inexpensive, and easily scalable and leads to depletion-mode EGFETs, which are fully functional at operation potentials below 2 V and allows us to increase V$_{th}$ by approximately 0.5 V

Artificial Neurons on Flexible Substrates: A Fully Printed Approach for Neuromorphic Sensing

Printed electronic devices have demonstrated their applicability in complex electronic circuits. There is recent progress in the realization of neuromorphic computing systems (NCSs) to implement basic synaptic functions using solution-processed materials. However, a fully printed neuron is yet to be realised. We demonstrate a fully printed artificial neuromorphic circuit on flexible polyimide (PI) substrate. Characteristic features of individual components of the printed system were guided by the software training of the NCS. The printing process employs graphene ink for passive structures and In2O3 as active material to print a two-input artificial neuron on PI. To ensure a small area footprint, the thickness of graphene film is tuned to target a resistance and to obtain conductors or resistors. The sheet resistance of the graphene film annealed at 300 °C can be adjusted between 200 Ω and 500 kΩ depending on the number of printed layers. The fully printed devices withstand a minimum of 2% tensile strain for at least 200 cycles of applied stress without any crack formation. The area usage of the printed two-input neuron is 16.25 mm2, with a power consumption of 37.7 mW, a propagation delay of 1 s, and a voltage supply of 2 V, which renders the device a promising candidate for future applications in smart wearable sensors

A Honeycomb Proportional Counter for Photon Multiplicity Measurement in the ALICE Experiment

A honeycomb detector consisting of a matrix of 96 closely packed hexagonal cells, each working as a proportional counter with a wire readout, was fabricated and tested at the CERN PS. The cell depth and the radial dimensions of the cell were small, in the range of 5-10 mm. The appropriate cell design was arrived at using GARFIELD simulations. Two geometries are described illustrating the effect of field shaping. The charged particle detection efficiency and the preshower characteristics have been studied using pion and electron beams. Average charged particle detection efficiency was found to be 98%, which is almost uniform within the cell volume and also within the array. The preshower data show that the transverse size of the shower is in close agreement with the results of simulations for a range of energies and converter thicknesses.Comment: To be published in NIM

The STAR Photon Multiplicity Detector

Details concerning the design, fabrication and performance of STAR Photon Multiplicity Detector (PMD) are presented. The PMD will cover the forward region, within the pseudorapidity range 2.3--3.5, behind the forward time projection chamber. It will measure the spatial distribution of photons in order to study collective flow, fluctuation and chiral symmetry restoration.Comment: 15 pages, including 11 figures; to appear in a special NIM volume dedicated to the accelerator and detectors at RHI

Identified baryon and meson distributions at large transverse momenta from Au+Au collisions at sNN=200\sqrt{s_{_{NN}}} = 200 GeV

Transverse momentum spectra of $\pi^{\pm}$, $p$ and $\bar{p}$ up to 12 GeV/c at mid-rapidity in centrality selected Au+Au collisions at $\sqrt{s_{_{NN}}} = 200$ GeV are presented. In central Au+Au collisions, both $\pi^{\pm}$ and $p(\bar{p})$ show significant suppression with respect to binary scaling at $p_T >$ 4 GeV/c. Protons and anti-protons are less suppressed than $\pi^{\pm}$, in the range 1.5 $< p_{T} <$6 GeV/c. The $\pi^-/\pi^+$ and $\bar{p}/p$ ratios show at most a weak $p_T$ dependence and no significant centrality dependence. The $p/\pi$ ratios in central Au+Au collisions approach the values in p+p and d+Au collisions at $p_T >$ 5 GeV/c. The results at high $p_T$ indicate that the partonic sources of $\pi^{\pm}$, $p$ and $\bar{p}$ have similar energy loss when traversing the nuclear medium.Comment: 6 pages, 4 figure

Pion interferometry in Au+Au collisions at sqrt[sNN]=200GeV

We present a systematic analysis of two-pion interferometry in Au+Au collisions at sqrt[sNN]=200GeV using the STAR detector at Relativistic Heavy Ion Collider. We extract the Hanbury-Brown and Twiss radii and study their multiplicity, transverse momentum, and azimuthal angle dependence. The Gaussianness of the correlation function is studied. Estimates of the geometrical and dynamical structure of the freeze-out source are extracted by fits with blast-wave parametrizations. The expansion of the source and its relation with the initial energy density distribution is studied

Longitudinal double-spin asymmetry and cross section for inclusive jet production in polarized proton collisions at sqrt(s) = 200 GeV

We report a measurement of the longitudinal double-spin asymmetry A_LL and the differential cross section for inclusive midrapidity jet production in polarized proton collisions at sqrt(s)=200 GeV. The cross section data cover transverse momenta 5 < pT < 50 GeV/c and agree with next-to-leading order perturbative QCD evaluations. The A_LL data cover 5 < pT < 17 GeV/c and disfavor at 98% C.L. maximal positive gluon polarization in the polarized nucleon.Comment: 6 pages, 3 figures. Minor changes from review process in Phys. Rev. Lett. Plain text tables of data in STAR publications may be found at http://www.star.bnl.gov/central/publications