831 research outputs found

    Monte Carlo program for the transport of neutrons and gamma rays

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    Computer program computes transport of neutrons and gamma rays in complex geometries and fluxes averaged over specified regions and surfaces of the geometry

    An Investigation of Complex Systems in 16 Dimensions

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    Sir Isaac Newton studied the world around him. He observed unexplainable phenomena that the math of his time could not prove. With the help of Gottfried Leibniz, he created infinitesimal calculus to prove his theories. The new concepts he created revolutionized science, and opened new realms of science previously unthought of. In 2002, Dr. Stephen Wolfram published A New Kind of Science, He argues that the processes of understanding cellular automata can be applied to other aspects of science. Dr. Rodrigo Obando of Columbus State University took Dr. Wolfram\u27s work and dissected it. By breaking down the rules, he started seeing patterns emerge in their ordering. He created a system for organizing the rules of the elementary cellular automaton rule space with 256 rules. From there, he guided me to the next rule space of size 4,294,967,296. 1 used his procedures to examine that rule space. My program takes a rule and displays all of the neighboring rules in that rule space. Essentially, I am taking a node of a 16-dimensional hypercube and showing all of the neighboring nodes. This design has not been publicly created to my or Dr. Obando\u27s knowledge. Understanding the patterns of cellular automata and what makes one rule different from a neighboring rule can be applied to other forms of science. This is what Dr. Stephen Wolfram stated in A New Kind of Science, and I firmly agree with his statement. Any exploration of the next rule space will bring us closer to seeing Dr. Wolfram\u27s theory come true

    The Rapid Induction of Cancers in the Hairless Mouse Utilizing the Principle of Photoaugmentation

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    We report a method for rapidly inducing cancer in the hairless mouse utilizing regimen in which an exposure to highly erythemogenic, but otherwise clinically non-injurious, dose of broad spectrum (290–400 nm) ultraviolet light is increased by 20% every 6th day. Clinical and histological observations reveal the presence of squamous cell cancer after as little as 18days of irradiation. The rate of cancer induction is enhanced by the 320–400nm component and this enhancement is shown to be a photoaugmentative effect. The results support the idea that stratum corneum and/or malpighian layer thickening produced in early stages of tumor induction tends to protect against the detrimental effects of UV radiation. Strict monitoring of both the spectral distribution and output of the radiation source is imperative for reproducible rates of tumor induction

    The Rapid Induction of Cancers in the Hairless Mouse Utilizing the Principle of Photoaugmentation

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    We report a method for rapidly inducing cancer in the hairless mouse utilizing regimen in which an exposure to highly erythemogenic, but otherwise clinically non-injurious, dose of broad spectrum (290–400 nm) ultraviolet light is increased by 20% every 6th day. Clinical and histological observations reveal the presence of squamous cell cancer after as little as 18days of irradiation. The rate of cancer induction is enhanced by the 320–400nm component and this enhancement is shown to be a photoaugmentative effect. The results support the idea that stratum corneum and/or malpighian layer thickening produced in early stages of tumor induction tends to protect against the detrimental effects of UV radiation. Strict monitoring of both the spectral distribution and output of the radiation source is imperative for reproducible rates of tumor induction

    Polyparameter linear free energy relationship for wood char–water sorption coefficients of organic sorbates

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    Author Posting. © The Author(s), 2015. This is the author's version of the work. It is posted here by permission of John Wiley & Sons for personal use, not for redistribution. The definitive version was published in Environmental Toxicology and Chemistry 34 (2015): 1464-1471, doi:10.1002/etc.2951.Black carbons (BCs), including soots, chars, activated carbons, and engineered nanocarbons, have different surface properties, but we do not know to what extent these affect their sorbent properties. To evaluate this for an environmentally ubiquitous form of BC, biomass char, we probed the surface of a well-studied wood char using 14 sorbates exhibiting diverse functional groups and then fit the data with a polyparameter linear free energy relationship (ppLFER) to assess the importance of the various possible sorbate-char surface interactions. Sorption from water to water-wet char evolved with the sorbate's degree of surface saturation and depended on only a few sorbate parameters: log Kd(L/kg) = [(4.03 ± 0.14) + (-0.15 ± 0.04) log ai)] V + [(-0.28 ± 0.04) log ai)] S + (-5.20 ± 0.21) B where ai is the aqueous saturation of the sorbate i, V is McGowan’s characteristic volume, S reflects polarity, and B represents the electron-donation basicity. As generally observed for activated carbon, the sorbate’s size encouraged sorption from water to the char, while its electron donation/proton acceptance discouraged sorption from water. However, the magnitude and saturation dependence differed significantly from what has been seen for activated carbons, presumably reflecting the unique surface chemistries of these two BC materials and suggesting BC-specific sorption coefficients will yield more accurate assessments of contaminant mobility and bioavailability and evaluation of a site's response to remediation.This material is based upon work supported by the U.S. Army Corps of Engineering, Humphreys Engineer Center Support Activity under Contract No. W912HQ-10-C-0005 awarded as part of the SERDP program.2016-05-1

    Cyclic cycle systems of the complete multipartite graph

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    In this paper, we study the existence problem for cyclic ℓ\ell-cycle decompositions of the graph Km[n]K_m[n], the complete multipartite graph with mm parts of size nn, and give necessary and sufficient conditions for their existence in the case that 2ℓ∣(m−1)n2\ell \mid (m-1)n

    A Comparison of Synovex ONE® Alone to Synovex Choice® Followed by Synovex Plus® as Implant Strategies for Finishing Heifers

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    A commercial feedlot study utilizing 1,737 crossbred heifers (initial BW 690 lb) compared the effect of two implant strategies [Synovex ONE Feedlot (day 0) or Synovex Choice (day 0) followed by Synovex Plus (day 95)] on performance and carcass characteristics. No differences were observed in carcass weight, final body weight, or gain, but heifers implanted with Synovex ONE Feedlot had slightly greater feed conversion and greater intake than heifers implanted using Synovex Choice/Synovex Plus. Heifers implanted with Synovex Choice/Synovex Plus had lower marbling score and yield grade, higher dressing percentage, and greater loin muscle area compared to heifers implanted with Synovex ONE Feedlot. Cattle implanted with Synovex ONE Feedlot showed a tendency for better quality grading compared to heifers implanted with Synovex Choice/Synovex Plus. These data suggest that implanting heifers with Synovex ONE Feedlot gives comparable growth to heifers implanted with Synovex Choice followed by Synovex Plus, with some changes in fatness when fed equal days

    Pemphigoid Antibody Mediated Attachment of Peripheral Blood Leukocytes at the Dermal-Epidermal Junction of Human Skin

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    It has been proposed that cutaneous inflammation and blister formation in bullous pemphigoid is caused by antibodies to the cutaneous basement membrane zone which activate complement, thereby, attracting leukocytes to the dermal-epidermal junction There is, however, no functional evidence which supports a role for pemphigoid antibodies in complement activation or leukocyte activity in skin. This study describes the in vitro attachment of human peripheral blood leukocytes to the dermal-epidermal junction of cryostat skin sections treated with 9/13 pemphigoid sera containing antibodies to the cutaneous basement membrane zone. A requirement for complement in the reaction was supported by the findings that only complement-fixing pemphigoid sera mediated the leukocyte response, a strong correlation existed between complement-fixation titers and leukocyte attachment titers and only leukocytes suspended in fresh serum but not buffer or heat in activated serum attached at the junction. A requirement for antibody was supported by the observation that IgG fractions of 4 pemphigoid sera were as effective as whole sera in mediating leukocyte attachment. The leukocyte response was shown to be specific for complement-fixing pemphigoid sera since it was not observed with non-complement-fixing sera or sera from 15 normal human and 22 non-pemphigoid disease controls. This study offers functional evidence for an interaction between pemphigoid anti-body, complement and leukocytes in the immunopathogenesis of bullous pemphigoid and demonstrates that complement fixing antibasement membrane zone antibodies may be important in initiating the cellular inflammatory events observed near the dermal-epidermal junction in viva

    BNNT- Mediated Irreversible Electroporation: It\u27s Potential on Cancer Cells

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    Irreversible lethal electroporation (IRE) is a new non-thermal ablation modality that uses short pulses of high amplitude static electric fields (up 1000V/cm) to create irreversible pores in the cell membrane, thus, causing cell death. Recently, IRE has emerged as a promising clinical modality for cancer disease treatment. Here, we investigated the responses of tumour human He La cells when subjected to IRE in the presence of BNNTs. These consist of tiny tubes of B and N atoms (arranged in hexagons) with diameters ranging from a 1 to 3 nanometres and lengths \u3c2 μm. BNNTs have attracted wide attention because of their unique electrical properties. We speculate that BNNTs, when interacting with cells exposed to static electrical fields, amplify locally the electric field, leading to cell death. In this work, electroporation assays were performed with a commercial electroporator using the cell-specific protocol suggested by the supplier (exponential decay wave, time constant 20ms) with the specific aim to compare IRE in absence and in presence of BNNTs. We observed that BNNTs have the capacity to decrease substantially the voltage required for IRE. When cells were pulsed at 800V/cm, we observed a 2,2-fold reduction in cell survival in the presence of BNNTs compared to controls. We conclude that the death of the tumour cells exposed to IRE is strongly enhanced in the presence of BNNTs, indicating their potential therapeutic application
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