Weed Development in Cereals under Different Growth Conditions and Control Intensities

ABSTRACT Histamine-producing Erwinia and Pluralibacter spp. capable of producing toxic histamine levels were isolated from ingredients commonly used in tuna salad preparations. The characterization and control of these histamine-producing bacteria are necessary to prevent illness from tuna salad consumption. We confirmed the identity of two Erwinia spp. and one Pluralibacter sp. previously isolated from tuna salad ingredients through whole genome sequencing and phylogenic analysis and characterized them for growth and histamine production at different temperatures, pH values, and salt concentrations. In addition, we examined the effects of dried vinegar (DV) powder on growth and histamine production of these strains in inoculated tuna salad preparations. Optimum growth temperatures in tryptic soy broth (TSB) for the two Erwinia spp. and one Pluralibacter sp. were 30.1, 31.1, and 33.9°C, respectively, and growth in TSB was observed at 5°C for both genera. Optimum histamine production of Erwinia persicina, Erwinia spp., and Pluralibacter spp. in TSB with histidine occurred from 25 to 30°C, pH 4 to 6, and 0 to 4% NaCl. No significant growth or histamine production was observed in tuna salad preparations stored at 4°C. Growth and histamine production by Erwinia or Pluralibacter spp. was inhibited in tuna salad containing celery and onion and 2% DV, whereas significant growth and histamine production occurred in tuna salad without DV. Understanding optimum growth conditions and histamine production can provide guidance to tuna salad manufacturers in formulating products and adjusting processing conditions that minimize hazards from these histamine-producing bacteria. Addition of 2% DV to tuna salad preparations may prevent histamine production in the event of temperature abuse. HIGHLIGHTS

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Screening of Highly Expressed Mycobacterial Genes Identifies Rv3615c as a Useful Differential Diagnostic Antigen for the Mycobacterium tuberculosis Complex

Infection and Immunity ◽

10.1128/iai.00150-08 ◽

2008 ◽

Vol 76 (9) ◽

pp. 3932-3939 ◽

Cited By ~ 69

Author(s):

Ben Sidders ◽

Chris Pirson ◽

Philip J. Hogarth ◽

R. Glyn Hewinson ◽

Neil G. Stoker ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Significant Proportion ◽

Growth Conditions ◽

Control Measures ◽

Human Populations ◽

Infected Cattle ◽

Ifn Γ ◽

Mycobacterial Antigens ◽

And Control ◽

Differential Antigens

ABSTRACT Tuberculous infections caused by mycobacteria, especially tuberculosis of humans and cattle, are important both clinically and economically. Human populations can be vaccinated with Mycobacterium bovis bacille Calmette-Guérin (BCG), and control measures for cattle involving vaccination are now being actively considered. However, diagnostic tests based on tuberculin cannot distinguish between genuine infection and vaccination with BCG. Therefore, identification of differential diagnostic antigens capable of making this distinction is required, and until now sequence-based approaches have been predominant. Here we explored the link between antigenicity and mRNA expression level, as well as the possibility that we may be able to detect differential antigens by analyzing quantified global transcriptional profiles. We generated a list of 14 candidate antigens that are highly expressed in Mycobacterium tuberculosis and M. bovis under a variety of growth conditions. These candidates were screened in M. bovis-infected and naïve cattle for the ability to stimulate a gamma interferon (IFN-γ) response. We identified one antigen, Rv3615c, which stimulated IFN-γ responses in a significant proportion of M. bovis-infected cattle (11 of 30 cattle [37%] [P < 0.01]) but not in naïve or BCG-vaccinated animals. Importantly, the same antigen stimulated IFN-γ responses in a significant proportion of infected cattle that did not respond to the well-characterized mycobacterial antigens ESAT-6 and CFP-10. Therefore, use of the Rv3615c epitope in combination with previously described differential tests based on ESAT-6 and CFP-10 has the potential to significantly increase diagnostic sensitivity without reducing specificity in BCG-vaccinated populations.

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Modelling and control of greenhouse system using neural networks

Transactions of the Institute of Measurement and Control ◽

10.1177/0142331216670235 ◽

2016 ◽

Vol 40 (3) ◽

pp. 918-929 ◽

Cited By ~ 11

Author(s):

A Manonmani ◽

T Thyagarajan ◽

M Elango ◽

S Sutha

Keyword(s):

Neural Network ◽

Neural Networks ◽

Moving Average ◽

Growth Conditions ◽

Operating Conditions ◽

Adverse Weather ◽

Control Schemes ◽

Non Linear ◽

Auto Regressive ◽

And Control

A greenhouse system (GHS) is a closed structure that facilitates modified growth conditions to crops and provides protection from pests, diseases and adverse weather. However, a GHS exhibits non-linearity due to the interaction between the biological subsystem and the physical subsystem. Non-linear systems are difficult to control, particularly when their characteristics change with time. These systems are best handled with methods of computation intelligence, such as artificial neural networks (ANNs) and fuzzy systems. In the present work, the approximation capability of a neural network is used to model and control sufficient growth conditions of a GHS. An optimal neural network-based non-linear auto regressive with exogenous input (NARX) time series model is developed for a GHS. Based on the NARX model, two intelligent control schemes, namely a neural predictive controller (NPC) and non-linear auto regressive moving average (NARMA-L2) controller are proposed to achieve the desired growth conditions such as humidity and temperature for a better yield. Finally, closed-loop performances of the above two control schemes for servo and regulatory operations are analysed for various operating conditions using performance indices.

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Weed development in cereals under different growth conditions and control intensities

Acta Agriculturae Scandinavica Section B - Soil & Plant Science ◽

10.1080/09064719909362509 ◽

1999 ◽

Vol 49 (3) ◽

pp. 134-142

Author(s):

Haldor Fykse ◽

Kjell Wærnhus

Keyword(s):

Growth Conditions ◽

And Control

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Review of polarity determination and control of GaN

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300000363 ◽

2004 ◽

Vol 9 ◽

Cited By ~ 90

Author(s):

M. Sumiya ◽

S. Fuke

Keyword(s):

Molecular Beam ◽

Chemical Vapor ◽

Growth Conditions ◽

Hydride Vapor Phase Epitaxy ◽

Nitride Semiconductors ◽

Sapphire Substrates ◽

Polarity Determination ◽

And Control ◽

Systematic Control ◽

Growth Methods

Polarity issues affecting III-V nitride semiconductors are reviewed with respect to their determination and control. A set of conditions crucial to the polarity control of GaN is provided for each of the following growth techniques; molecular beam epitaxy (MBE), pulsed laser deposition (PLD) and hydride vapor phase epitaxy (HVPE). Although GaN films might have been deposited by identical growth methods using the same buffer layer technologies, there is often a conflict between the resulting polarities achieved by different research groups. In this paper, we present the implications of the conditions used in each of the processes used for two-step metalorganic chemical vapor deposition (MOCVD), demonstrating systematic control of the polarity of GaN films on sapphire substrates. The potential for confusion in polarity control will be explained, taking into account the implications clarified in our studies. The correlation between the polarity and the growth conditions will be discussed in order to provide a mechanism for the determination and control of the crystal polarity during the growth of GaN films.

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The Optimization of Niobium Diselenide Thin Films Through Control of Pulsed Laser Deposition Parameters

MRS Proceedings ◽

10.1557/proc-285-539 ◽

1992 ◽

Vol 285 ◽

Cited By ~ 2

Author(s):

Allan E. Day ◽

Samuel J.P. Laube ◽

M.S. Donley ◽

J.S. Zabinski

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Pulsed Laser ◽

Optimal Growth ◽

Growth Conditions ◽

Laser Deposition ◽

Film Properties ◽

Niobium Diselenide ◽

Deposition Parameters ◽

And Control

ABSTRACTNiobium diselenide has potential for use as a conductive lubricant, but to achieve the optimal properties of low friction coefficient, high conductivity and oxidation resistance, the SeJNb ratio and crystallinity must be carefully controlled. It has been shown that Pulsed Laser Deposition (PLD) permits the required degree of control, even over films with complex stoichiometries. (4–8). In this study, PLD was used to grow stoichiometric, crystalline thin films of niobium diselenide and to study the effects of laser deposition parameters on film properties. Film chemistry and crystallinity were evaluated using XPS, RBS, and glancingangle XRD. Friction and wear measurements were taken on a ball-on-flat tribometer. The deposition apparatus incorporates a fully computerized data acquisition and control system that facilitated the correlation of the laser deposition parameters to film properties. This study has shown that film chemistry could be changed from substoichiometric to superstoichiometric and crystallinity varied between amorphous to highly crystalline by appropriate choice of PLD parameters. The property correlations and acquisition system that permitted the identification of the optimal growth conditions will be described.

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Monitoring and Control in Vapor phase Epitaxy

MRS Proceedings ◽

10.1557/proc-502-117 ◽

1997 ◽

Vol 502 ◽

Author(s):

T. P. Pearsall

Keyword(s):

Control System ◽

Vapor Deposition ◽

Chemical Vapor ◽

Growth Conditions ◽

Temperature Control System ◽

Monitoring And Control ◽

Non Invasive ◽

Innovative Solutions ◽

Precision And Accuracy ◽

And Control

ABSTRACTMonitoring and control in epitaxy based on chemical vapor deposition is a challenge created by growth conditions that often preclude more common sensors like thermocouples and mass spectrometry. We report results of experiments to measure and control temperature and flux by non-invasive optical sensing. We have developed a temperature control system with precision and accuracy better that 5°C. Satisfactory control of flux poses difficulties that will require innovative solutions before a useful control system can be developed.

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Epigenetic Drifts during Long-Term Intestinal Organoid Culture

Cells ◽

10.3390/cells10071718 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1718

Author(s):

Torsten Thalheim ◽

Susann Siebert ◽

Marianne Quaas ◽

Maria Herberg ◽

Michal R. Schweiger ◽

...

Keyword(s):

Gene Activation ◽

Growth Conditions ◽

Dna Demethylation ◽

Metabolic Adaptation ◽

Long Term Culture ◽

Organoid Culture ◽

Transcriptional Changes ◽

Tissue Of Origin ◽

And Control

Organoids retain the morphological and molecular patterns of their tissue of origin, are self-organizing, relatively simple to handle and accessible to genetic engineering. Thus, they represent an optimal tool for studying the mechanisms of tissue maintenance and aging. Long-term expansion under standard growth conditions, however, is accompanied by changes in the growth pattern and kinetics. As a potential explanation of these alterations, epigenetic drifts in organoid culture have been suggested. Here, we studied histone tri-methylation at lysine 4 (H3K4me3) and 27 (H3K27me3) and transcriptome profiles of intestinal organoids derived from mismatch repair (MMR)-deficient and control mice and cultured for 3 and 20 weeks and compared them with data on their tissue of origin. We found that, besides the expected changes in short-term culture, the organoids showed profound changes in their epigenomes also during the long-term culture. The most prominent were epigenetic gene activation by H3K4me3 recruitment to previously unmodified genes and by H3K27me3 loss from originally bivalent genes. We showed that a long-term culture is linked to broad transcriptional changes that indicate an ongoing maturation and metabolic adaptation process. This process was disturbed in MMR-deficient mice, resulting in endoplasmic reticulum (ER) stress and Wnt activation. Our results can be explained in terms of a mathematical model assuming that epigenetic changes during a long-term culture involve DNA demethylation that ceases if the metabolic adaptation is disturbed.

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