Some Properties of a DNA -Dependent RNA Polymerase from Halobacterium cutirubrum

1973 ◽  
Vol 51 (9) ◽  
pp. 1297-1304 ◽  
Author(s):  
L. L. Chazan ◽  
S. T. Bayley
Keyword(s):  
High Speed ◽  
Enzyme Preparation ◽  
Nearest Neighbor ◽  
Equal Proportion ◽  
Trichloracetic Acid ◽  
Sephadex Column ◽  
Membrane Complex ◽  
Irreversible Denaturation ◽  
Insoluble Product ◽  
Dna Template

A DNA–protein–membrane complex, which incorporated ribonucleoside triphosphates (rNTP's) into a cold trichloracetic acid insoluble product, was isolated from an homogenate of the extremely halophilic Halobacterium cutirubrum by high speed centrifugation. After digestion with DNase and chromatography on a Sephadex column, the complex yielded an enzyme preparation which incorporated rNTP's in the presence of added DNA. Incorporation by both the complex and the enzyme preparation depended on all four rNTP's and was sensitive to DNase and RNase. Nearest-neighbor analyses showed that the product from the partially purified enzyme contained all four rNTP's in roughly equal proportion. The enzyme was inhibited by actinomycin D and acriflavin but not by rifampicin or streptovaricin. It showed no specificity for DNA templates. From Sephadex chromatography and centrifugation on glycerol gradients, its molecular weight was estimated to be roughly 300 000 – 400 000 daltons.For incorporation, the optimum Mg2+ concentration was 40 mM. The complex was active at all concentrations of KCl or NH4Cl up to saturation, but the partially purified enzyme was active only below 0.4 M. The lack of activity at higher concentrations was not due to irreversible denaturation of the enzyme but concentrated salt may have inhibited the reaction by altering the configuration of the DNA template.

scholarly journals Deoxyribonucleic acid-dependent ribonucleic acid polymerases from murine spleen cells. Increased amounts of the nucleolar species in leukaemic tissue

1973 ◽  
Vol 133 (4) ◽  
pp. 797-804 ◽  
Author(s):  
Donner F. Babcock ◽  
Marvin A. Rich
Keyword(s):  
Rna Synthesis ◽  
Rna Polymerases ◽  
Infected Tissue ◽  
Leukaemia Virus ◽  
Bivalent Cations ◽  
Murine Spleen ◽  
Insoluble Product ◽  
Polymerase I ◽  
Dna Template ◽  
Nucleolar Rna

1. In the spleens of infected mice, the Friend leukaemia virus induces a sharp increase in the ability of subsequently isolated nuclei to incorporate exogenous UTP into an acid-insoluble product. Inhibitor studies indicate that the incremental RNA synthesis proceeds from a DNA template and that both nucleolar and nucleoplasmic activities are involved. 2. The partially purified DNA-dependent RNA polymerases from control and virus-infected tissue are indistinguishable with respect to chromatographic mobility, dependence on bivalent cations, ionic strength, pH and their susceptibility to α-amanitin. The RNA polymerases of the murine spleen resemble the enzymes of other mammalian tissue in these properties. 3. A comparison of the amount of polymerase solubilized from normal and infected tissue correlates with the activity observed in assays of the respective nuclei. These experiments indicated that the increase in nucleolar RNA synthesis after infection is mediated by increased extractable polymerase I activity whereas the change in nucleoplasmic RNA synthesis results from an alteration of chromatin or a chromatin-associated factor.

A random search methodology for examining parametric uncertainty in water quality models

2006 ◽  
Vol 53 (1) ◽  
pp. 33-40 ◽  
Author(s):  
O.O. Osidele ◽  
W. Zeng ◽  
M.B. Beck
Keyword(s):  
Water Quality ◽  
High Speed ◽  
Nutrient Dynamics ◽  
Nearest Neighbor ◽  
Optimal Parameter ◽  
Random Search ◽  
Parametric Uncertainty ◽  
Simulation Models ◽  
Quality Model ◽  
Rejection Algorithm

The advent of the modern high-speed digital computer has tremendously enhanced the utility of Monte Carlo methods for evaluating complex environmental simulation models. In particular, random searching is becoming popular, as thousands of model runs can now be executed quickly and with minimal effort. Indeed, the issues of computational burden and inefficiency, hitherto the bane of random searching, are now receding. This paper presents one such method, uniform covering by probabilistic rejection (UCPR), which combines a pure random search with a probabilistic rejection algorithm that significantly enhances its efficiency. Using nearest-neighbor distances, an ensemble of points in a predefined parameter sampling domain migrates to locate and define a final distribution of optimal parameter vectors, thus providing a realistic depiction of parameter uncertainty. In a prototypical case study of the Oconee River (Georgia, USA), UCPR and regionalized sensitivity analysis, are employed for identifying the parameters of sediment-transport-associated nutrient dynamics, a dynamic river water quality model. Results indicate the existence of a complex interactive parameter structure, evidenced by multiple sets of optimal points widely dispersed over a broad domain of feasible parameter values.

Surface defect detection for high-speed rails using an inverse P-M diffusion model

Sensor Review ◽  
2016 ◽  
Vol 36 (1) ◽  
pp. 86-97 ◽  
Author(s):  
Zhendong He ◽  
Yaonan Wang ◽  
Feng Yin ◽  
Jie Liu
Keyword(s):  
Diffusion Model ◽  
Defect Detection ◽  
High Speed ◽  
Surface Defect ◽  
Nearest Neighbor ◽  
Inspection System ◽  
Content Type ◽  
Difference Image ◽  
Vision Inspection ◽  
Surface Defect Detection

Purpose – When using a machine vision inspection system for rail surface defect detection, many complex factors such as illumination changes, reflection inequality, shadows, stains and rust might inevitably deform the scanned rail surface image. This paper aims to reduce the influence of these factors, a pipeline of image processing algorithms for robust defect detection is developed. Design/methodology/approach – First, a new inverse Perona-Malik (P-M) diffusion model is presented for image enhancement, which takes the reciprocal of gradient as feature to adjust the diffusion coefficients, and a distinct nearest-neighbor difference scheme is introduced to select proper defect boundaries during discretized implementation. As a result, the defect regions are sufficiently smoothened, whereas the faultless background remains unchanged. Then, by subtracting the diffused image from the original image, the defect features will be highlighted in the difference image. Subsequently, an adaptive threshold binarization, followed by an attribute opening like filter, can easily eliminate the noisy interferences and find out the desired defects. Findings – Using data from our developed inspection apparatus, the experiments show that the proposed method can attain a detection and measurement precisions as high as 93.6 and 85.9 per cent, respectively, while the recovery accuracy remains 93 per cent. Additionally, the proposed method is computationally efficient and can perform robustly even under complex environments. Originality/value – A pipeline of algorithms for rail surface detection is proposed. Particularly, an inverse P-M diffusion model with a distinct discretization scheme is introduced to enhance the defect boundaries and suppress noises. The performance of the proposed method has been verified with real images from our own developed system.

EFFECT OF TRICHLORACETIC ACID ON BASOPHILS AND ON CORTICOTROPHIN CONTENT OF HUMAN PITUITARY GLANDS: EXTRACTION OF LOW MOLECULAR WEIGHT CORTICOTROPHIN

1963 ◽  
Vol 42 (1) ◽  
pp. 69-84 ◽  
Author(s):  
A. R. Currie ◽  
Beryl M. A. Davies
Keyword(s):  
Molecular Weight ◽  
Column Chromatography ◽  
Periodic Acid ◽  
Low Molecular Weight ◽  
Posterior Lobe ◽  
Human Pituitary ◽  
Trichloracetic Acid ◽  
Simple Method ◽  
Sephadex Column ◽  
Pituitary Glands

ABSTRACT Experiments are reported which show that 2.5% trichloracetic acid (TCA) causes marked loss of periodic acid-Schiff staining of the basophil granules of the pituitary gland and that there is extraction of some ACTH into the TCA. There is, however, no direct correlation between the basophil changes and the extraction of the hormone from the gland. The vesiculate chromophobe, the colloid and the cytoplasmic granules of the acidophils are not apparently affected by TCA treatment. Little is known about the chemical state of storage of ACTH in the human adenohypophysis. The amino acid structure and sequence of human ACTH has recently been proposed but there is as yet no chemical basis for a histochemical technique specific for ACTH. The 2.5% TCA-extractable ACTH, which represents about 30% of the total ACTH activity of batches of 'old' pituitary glands, has been characterized by ultrafiltration, Sephadex column chromatography and ultracentrifugation as a single component of minimum molecular weight about 3200. This is a simple method for extracting low molecular weight ACTH-extraction in 2.5% TCA (or water acidified to pH 5.0) for 1 hour at 4° C followed by ultrafiltration and Sephadex column chromatography. About 68% of the original activity in the TCA extract is recovered in the final product. Extraction was equally efficient whether 'pieces' or homogenates were used and in the presence or absence of posterior lobe tissue. Autolysis results in a decrease of both residual gland and TCA-extractable hormone.

Nearest Neighbor Classification for High-Speed Big Data Streams Using Spark

2017 ◽  
Vol 47 (10) ◽  
pp. 2727-2739 ◽  
Author(s):  
Sergio Ramirez-Gallego ◽  
Bartosz Krawczyk ◽  
Salvador Garcia ◽  
Michal Wozniak ◽  
Jose Manuel Benitez ◽  
...  
Keyword(s):  
Big Data ◽  
Data Streams ◽  
High Speed ◽  
Nearest Neighbor ◽  
Nearest Neighbor Classification ◽  
Big Data Streams ◽  
Neighbor Classification

CU-Track: A Multi-Camera Framework for Real-Time Multi-Object Tracking

2013 ◽  
Vol 415 ◽  
pp. 325-332
Author(s):  
Pongsakon Bamrungthai ◽  
Viboon Sangveraphunsiri
Keyword(s):  
Object Tracking ◽  
Real Time ◽  
High Speed ◽  
Nearest Neighbor ◽  
Data Transfer ◽  
Target Object ◽  
Processing Unit ◽  
Process Data ◽  
Pc Cluster ◽  
High Speed Data

This paper presents CU-Track, a multi-camera framework for real-time multi-object tracking. The developed framework includes a processing unit, the target object, and the multi-object tracking algorithm. A PC-cluster has been developed as the processing unit of the framework to process data in real-time. To setup the PC-cluster, two PCs are connected by using PCI interface cards that memory can be shared between the two PCs to ensure high speed data transfer and low latency. A novel mechanism for PC-to-PC communication is proposed. It is realized by a dedicated software processing module called the Cluster Module. Six processing modules have been implemented to realize system operations such as camera calibration, camera synchronization and 3D reconstruction of each target. Multiple spherical objects with the same size are used as the targets to be tracked. Two configurations of them, active and passive, can be used for tracking by the system. The algorithm based on Kalman filter and nearest neighbor searching is developed for multi-object tracking. Two applications have been implemented on the system, which confirm the validity and effectiveness of the developed framework.

An Effective Adaptive Autocorrelation-Based Neighboring Matching Location-Aware Computing in WLANs

2011 ◽  
Vol 204-210 ◽  
pp. 2011-2014
Author(s):  
Yu Bin Xu ◽  
Mu Zhou ◽  
Lin Ma
Keyword(s):  
High Speed ◽  
Wireless Local Area Network ◽  
Nearest Neighbor ◽  
Local Area Network ◽  
Local Area ◽  
Measured Signal ◽  
Area Network ◽  
K Nearest Neighbor ◽  
Context Aware Computing ◽  
High Efficient

The recent advances of ubiquitous wireless infrastructures and requirements for high speed context-aware computing have created the opportunities to supply the high efficient location based service (LBS) in indoor wireless local area network (WLAN) environment. Because of the serious multi-path effect, unpredictable co-channel interference and inherent equipment noise, the measured signal strengths vary a lot in the real-world indoor environment. And this strength variation will also result in the performance deterioration of radio map-based neighboring matching algorithm. In response to this compelling problem, we propose the adoption of adaptive autocorrelation-based signal preprocessing method as a specific solution by effectively eliminating the singular strength from the original fingerprint set. Finally, the feasibility and effectiveness of autocorrelation-based preprocessing are also verified by decreasing about 33.4% and 32.9% of errors in k nearest neighbor (KNN) and weighted KNN (WKNN).

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