scholarly journals Toward organism identification through analysis of bacterial colonies.

1977 ◽  
Vol 25 (7) ◽  
pp. 702-706
Author(s):  
M D Graham
Keyword(s):  
Experimental System ◽  
Clinical Problem ◽  
Growth Conditions ◽  
Surface Scattering ◽  
Bacterial Identification ◽  
Multi Wavelength ◽  
Boundary Characteristics ◽  
Organism Identification ◽  
Reflectance Data ◽  
Better Than

The clinical problem of bacterial identification has been approached by applying pattern-recognition techniques to multi-wavelength surface-scattering and reflectance data derived from real-time scans of isolated colonies. Preliminary results, obtained from blood-agar plates inoculated with a mixture of staphylococci, streptococci and escherichieae, indicate that these organisms can be differentiated with better than 90% certainty, provided the colonies are physically separated and their growth conditions closely controlled. Data collection and classification characteristics of the experimental system are briefly described; it is felt that the technique, possibly expanded to include boundary characteristics of the colonies, may offer a viable means of identifying clinically important bacteria.

Efficient and Semiefficient Vulcanization Systems Employing 2-(Morpholinodithio)-Benzothiazole Generated in Situ

1977 ◽  
Vol 50 (1) ◽  
pp. 90-98
Author(s):  
J. P. Lawrence
Keyword(s):  
Heat Resistance ◽  
Experimental System ◽  
Heat Resistant ◽  
Molar Basis ◽  
Direct Replacement ◽  
Better Than

Abstract The MBTS-N-(morpholinothio)phthalimide vulcanization system has been found to be effective in producing heat resistant semi-EV and EV cures in a variety of representative rubbers. When used as a direct replacement on a molar basis for 2-(morpholinodithio)benzothiazole (MDB), improvements in processing safety were found in all cases studied. In this respect it is most effective in NR, SBR, and NBR. The experimental system also generally gave slower-curing stocks. The heat resistance of the experimental stocks was found to be equal to or better than that of the MDB control stocks. Substantial improvements in heat resistance for both SBR and IIR unexpectedly resulted from the use of the MBTS—imide system. This result suggests that the nature of the crosslinks formed by the two vulcanization systems are to some extent different in these two elastomers. This, in turn, may reflect upon the mechanisms of crosslink formation.

Deposition of epitaxial transition metal carbide films and superlattices by simultaneous direct current metal magnetron sputtering and C60 evaporation

2001 ◽  
Vol 16 (3) ◽  
pp. 633-643 ◽  
Author(s):  
H. Högberg ◽  
J. Birch ◽  
M. P. Johansson ◽  
L. Hultman ◽  
U. Jansson
Keyword(s):  
Epitaxial Growth ◽  
Deposition Process ◽  
Growth Conditions ◽  
Growth Behavior ◽  
Transition Metal Carbide ◽  
Structural Quality ◽  
Metal Carbide ◽  
General Observation ◽  
Better Than

Thin epitaxial TiC and VC films and superlattices have been deposited on MgO(001) by simultaneous sputtering of the metals and evaporation of C60. It was found that epitaxial growth conditions for TiC could be maintained down to a temperature of 100 °C, while the epitaxial growth of VC required 200 °C. Epitaxial VC films were completely relaxed at all growth temperatures, while a change from a relaxed to a strained growth behavior was observed for TiC films. The structural quality of the TiC films was better than for the VC films. A general observation was that a plasma-assisted deposition process yields films with a higher quality and allows epitaxial growth at lower temperatures than for a pure coevaporation process.

Effect of Microwave Drying on Dyeing Rate of Cotton Yarn

2011 ◽  
Vol 328-330 ◽  
pp. 1619-1622 ◽  
Author(s):  
Zi Na Zhu ◽  
Zhuo Meng ◽  
Guang Chao An ◽  
Yi Ze Sun
Keyword(s):  
Liquid Ammonia ◽  
Engineering Application ◽  
Experimental System ◽  
New Method ◽  
Microwave Drying ◽  
Good Effect ◽  
Cotton Yarn ◽  
Steam Drying ◽  
Dyeing Rate ◽  
Better Than

Focusing on the residual amount of liquid ammonia in modified cotton yarn, this paper presents a new method of drying the liquid ammonia by microwave. An experimental system is designed to find whether this new method is correct and to analyse the effect of microwave drying on the dyeing rate of cutton yarn. Firstly, the microwave drying experiment is carried out to prove that this new drying method is better than the traditional steam drying way. Then, another contrast experiment on the dyeing rate confirms the good effect of microwave drying. So it is concluded that microwave drying is an efficient and energy-saving way to remove the remaining liquid ammonia. Meanwhile, the experimental results provide the relevant data to make guiding sense to engineering application.

High Quality Uniform SiC Epitaxy for Power Device Applications

2007 ◽  
Vol 556-557 ◽  
pp. 101-104
Author(s):  
Jie Zhang ◽  
Esteban Romano ◽  
Janice Mazzola ◽  
Swapna G. Sunkari ◽  
Carl Hoff ◽  
...  
Keyword(s):  
Growth Conditions ◽  
Average Deviation ◽  
Low Leakage ◽  
Low Leakage Current ◽  
Device Applications ◽  
Abrupt Interface ◽  
P Type ◽  
Highly Uniform ◽  
Controlled Doping ◽  
Better Than

In this paper we present highly uniform SiC epitaxy in a horizontal hot-wall CVD reactor with wafer rotation. Epilayers with excellent thickness uniformity of better than 1% and doping uniformity better than 5% are obtained on 3-in, 4° off-axis substrates. The same growth conditions for uniform epitaxy also generate smooth surface morphology for the 4° epiwafers. Well controlled doping for both n- and p-type epilayers is obtained. Abrupt interface transition between n- and pdoped layers in a wide doping range is demonstrated. Tight process control for both thickness and doping is evidenced by the data collected from the epi operations. The average deviation from target is 2.5% for thickness and 6% for doping. PiN diodes fabricated on a standard 3-in, 4° epiwafer have shown impressive performance. More than half of the 1 mm2 devices block 1 kV (2.3 MV/cm) with a low leakage current of 1 μA.

scholarly journals Mothers determine offspring size in response to own juvenile growth conditions

2006 ◽  
Vol 2 (2) ◽  
pp. 225-228 ◽  
Author(s):  
Barbara Taborsky
Keyword(s):  
Maternal Effects ◽  
Environmental Conditions ◽  
Larval Growth ◽  
Cichlid Fish ◽  
Growth Conditions ◽  
Offspring Size ◽  
Juvenile Growth ◽  
Natural Conditions ◽  
Offspring Quality ◽  
Better Than

Through non-genetic maternal effects, mothers can tailor offspring phenotype to the environment in which young will grow up. If juvenile and adult ecologies differ, the conditions mothers experienced as juveniles may better predict their offspring's environment than the adult environment of mothers. In this case maternal decisions about investment in offspring quality should already be determined during the juvenile phase of mothers. I tested this hypothesis by manipulating juvenile and adult maternal environments independently in a cichlid fish. Females raised in a poor environment produced larger young than females raised without food limitations, irrespective of the feeding conditions experienced during adulthood. This maternal boost was due to a higher investment in eggs and to faster larval growth. Apparently, mothers prepare their offspring for similar environmental conditions to those they encountered as juveniles. This explanation is supported by the distribution of these fishes under natural conditions. Juveniles live in a different and much narrower range of habitats than adults. Therefore, the habitat mothers experienced as juveniles will allow them to predict their offspring's environment better than the conditions in the adult home range.

A LOW COST MACRO-MICRO POSITIONING SYSTEM WITH SMA-ACTUATED MICRO STAGE

2007 ◽  
Vol 31 (1) ◽  
pp. 75-95 ◽  
Author(s):  
Eric Ho ◽  
Rob Gorbet
Keyword(s):  
Smart Materials ◽  
Lower Cost ◽  
Position Control ◽  
Low Cost ◽  
Experimental System ◽  
Positioning System ◽  
Positioning Systems ◽  
Mechanical Amplification ◽  
Micro Systems ◽  
Better Than

Macro-micro systems allow high-resolution positioning over greater ranges of operation that would be achievable with precision positioning systems. Piezoceramic actuators have established themselves as the principle technology for commercial micro-positioning applications, and the trend in research is to push the limits of resolution down to the nanometer and sub-nanometer scales. Other smart materials offer the potential for lightweight, continuous actuation over small ranges, and hence may be useful in micro-positioning applications. This work focuses on the potential for SMA actuators to enable low-cost micro-positioning. Compared to piezos, SMA offer longer range and lower actuation voltages, enabling lower-cost drive electronics and removing the need for costly precision mechanical amplification stages. A prototype single-axis macro-micro positioning system is described, with a macro range of 200 mm and relative positioning precision of better than 5 5μm. The micro stage is driven by an NM70 SMA actuator from NanoMuscle. Macro and micro stages are modelled and controllers developed, and experimental system performance is evaluated. The success of the system provides an inexpensive platform for the study of macro-micro positioning issues such as stage coupling, friction, and drive flexibility, as well as for the position control of SMA.

scholarly journals A Comparison of Regression Tree Approaches to Modelling the Efficacy of Water Hyacinth Biocontrol Using Multitemporal Spectral Datasets

2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
Na’eem Hoosen Agjee ◽  
Onisimo Mutanga ◽  
Michael Gebreselasie ◽  
Riyad Ismail
Keyword(s):  
Water Hyacinth ◽  
Regression Tree ◽  
Regression Trees ◽  
Predictive Performance ◽  
Canopy Reflectance ◽  
Model Interpretation ◽  
Leaf Chlorophyll ◽  
Single Target ◽  
Reflectance Data ◽  
Better Than

Water hyacinth (Eichhornia crassipes) is an exotic plant species that is effectively controlled byNeochetinaspp. weevils. This study is aimed at determining if spectroscopic data may be utilized to predict insect-induced stress on water hyacinth plants. Single target regression trees (STRTs), multitarget regression trees (MTRTs), and random forest multitarget regression trees (RF-MTRTs) have been used to predict feeding scar damage (FSD) and relative leaf chlorophyll content (RLCC) from hyperspectral canopy reflectance data. Results from this study show that the correlation coefficient of STRTs (training accuracy: 76%–97%; validation accuracy: 47%–86%) performs better than MTRTs (training accuracy: 74%–90%; validation accuracy: 45%–77%) for all infestation levels but are difficult to interpret simultaneously. In contrast, MTRTs (size: 23–35 nodes) are much smaller and more interpretable than STRTs (size: 11–47 nodes) because they predict FSD and RLCC simultaneously. Importantly, RF-MTRTs (training accuracy: 95%–98%; validation accuracy: 55%–88%) yield better predictive performance than STRTs and MTRTs for all infestation levels. It is concluded that MTRTs can be utilized for model interpretation as they are more interpretable; however, RF-MTRTs offer an improved predictive performance.

Application of Machine Learning Algorithms to a Well Defined Clinical Problem: Liver Disease

2017 ◽  
Vol 8 (4) ◽  
pp. 38-60 ◽  
Author(s):  
Sakshi Takkar ◽  
Aman Singh ◽  
Babita Pandey
Keyword(s):  
Machine Learning ◽  
Liver Disease ◽  
Clinical Problem ◽  
Machine Learning Algorithms ◽  
Classification Model ◽  
Integrated Models ◽  
Major Health ◽  
And Performance ◽  
Dimensionality Reduction Method ◽  
Better Than

Liver diseases represent a major health burden worldwide. Machine learning (ML) algorithms have been extensively used to diagnose liver disease. This study accordingly aims to employ various individual and integrated ML algorithms on distinct liver disease datasets for evaluating the diagnostic performances, to integrate dimensionality reduction method with the ML algorithms for analyzing variation in results, to find the best classification model and to analyze the merits and demerits of these algorithms. KNN and PCA-KNN emerged to be the top individual and integrated models. The study also concluded that one specific algorithm can't show best results for all types of datasets and integrated models not always perform better than the individuals. It is observed that no algorithm is perfect and performance of an algorithm totally depends on the dataset type and structure, its number of observations, its dimensions and the decision boundary.

scholarly journals Comparison of lipidome profiles of Caenorhabditis elegans—results from an inter-laboratory ring trial

Metabolomics ◽  
2021 ◽  
Vol 17 (3) ◽  
Author(s):  
Britta Spanier ◽  
Anne Laurençon ◽  
Anna Weiser ◽  
Nathalie Pujol ◽  
Shizue Omi ◽  
...  
Keyword(s):  
Caenorhabditis Elegans ◽  
Model Organism ◽  
Experimental System ◽  
Growth Conditions ◽  
Culture Conditions ◽  
Lipid Profiling ◽  
Ring Trial ◽  
Novel Biomarkers ◽  
The Individual ◽  
Qualitative Changes

Abstract Introduction Lipidomic profiling allows 100s if not 1000s of lipids in a sample to be detected and quantified. Modern lipidomics techniques are ultra-sensitive assays that enable the discovery of novel biomarkers in a variety of fields and provide new insight in mechanistic investigations. Despite much progress in lipidomics, there remains, as for all high throughput “omics” strategies, the need to develop strategies to standardize and integrate quality control into studies in order to enhance robustness, reproducibility, and usability of studies within specific fields and beyond. Objectives We aimed to understand how much results from lipid profiling in the model organism Caenorhabditis elegans are influenced by different culture conditions in different laboratories. Methods In this work we have undertaken an inter-laboratory study, comparing the lipid profiles of N2 wild type C. elegans and daf-2(e1370) mutants lacking a functional insulin receptor. Sample were collected from worms grown in four separate laboratories under standardized growth conditions. We used an UPLC-UHR-ToF–MS system allowing chromatographic separation before MS analysis. Results We found common qualitative changes in several marker lipids in samples from the individual laboratories. On the other hand, even in this controlled experimental system, the exact fold-changes for each marker varied between laboratories. Conclusion Our results thus reveal a serious limitation to the reproducibility of current lipid profiling experiments and reveal challenges to the integration of such data from different laboratories.

scholarly journals A Novel Staphylococcus aureus Biofilm Phenotype Mediated by the Fibronectin-Binding Proteins, FnBPA and FnBPB

2008 ◽  
Vol 190 (11) ◽  
pp. 3835-3850 ◽  
Author(s):  
Eoghan O'Neill ◽  
Clarissa Pozzi ◽  
Patrick Houston ◽  
Hilary Humphreys ◽  
D. Ashley Robinson ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Biofilm Formation ◽  
Binding Proteins ◽  
Clinical Problem ◽  
Growth Conditions ◽  
Surface Proteins ◽  
Fibrinogen Binding ◽  
Fibronectin Binding ◽  
Mrsa Strains ◽  
Biofilm Development

ABSTRACT Device-associated infections involving biofilm remain a persistent clinical problem. We recently reported that four methicillin-resistant Staphylococcus aureus (MRSA) strains formed biofilm independently of the icaADBC-encoded exopolysaccharide. Here, we report that MRSA biofilm development was promoted under mildly acidic growth conditions triggered by the addition of glucose to the growth medium. Loss of sortase, which anchors LPXTG-containing proteins to peptidoglycan, reduced the MRSA biofilm phenotype. Furthermore introduction of mutations in fnbA and fnbB, which encode the LPXTG-anchored multifunctional fibrinogen and fibronectin-binding proteins, FnBPA and FnBPB, reduced biofilm formation by several MRSA strains. However, these mutations had no effect on biofilm formation by methicillin-sensitive S. aureus strains. FnBP-promoted biofilm occurred at the level of intercellular accumulation and not primary attachment. Mutation of fnbA or fnbB alone did not substantially affect biofilm, and expression of either gene alone from a complementing plasmid in fnbA fnbB mutants restored biofilm formation. FnBP-promoted biofilm was dependent on the integrity of SarA but not through effects on fnbA or fnbB transcription. Using plasmid constructs lacking regions of FnBPA to complement an fnbAB mutant revealed that the A domain alone and not the domain required for fibronectin binding could promote biofilm. Additionally, an A-domain N304A substitution that abolished fibrinogen binding did not affect biofilm. These data identify a novel S. aureus biofilm phenotype promoted by FnBPA and FnBPB which is apparently independent of the known ligand-binding activities of these multifunctional surface proteins.

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