scholarly journals Effect of uncontrolled fermentation and soaking on antinutrients of Tacca leontopetaloides (L) Kuntze (Taccaceae) tuber flour

2022 ◽  
Vol 10 (1) ◽  
pp. 1-9
Author(s):  
Collinlaw Joseph Ndouyang ◽  
Passannet Augustin Schinzoumka
Keyword(s):  
Statistical Analysis ◽  
Principal Components ◽  
Enzymatic Degradation ◽  
Water Levels ◽  
Chemical Methods ◽  
Microbial Enzymes ◽  
Soluble Components

Soaking and fermentation are two food technologies that are used by households or agro-industrial establishments. These practices aim at improving food nutritional acceptability and sensorial parameters. Tacca leontopetaloides tuber was used to study alleviation of antinutrients by solubilization and leaching through soaking, or by enzymatic degradation through fermentation. Soaking has lasted 72 hrs, and fermentation 48 hrs. Chemical methods have been used to determinate antinutrient levels in processed and unprocessed T. leontopetaloides tubers slices. A statistical analysis by means of XLSTAT was purchased for principal components and correlations between variables. Results show that the major antinutrients have exhibited resistance to microbial enzymes during fermentation or to solubilization in water. Levels of most antinutrients have increased instead of lowering when tacca tuber slices were soaked or fermented. The increase of components during soaking and fermentation is linked to the decrease of soluble components in T. leontopetaloides slices. Phytate is an antinutrient which resists to both food technologies, and saponins can be leached by 43.4 % through soaking or by 50.7 % during fermentation. These powerful antinutrients in T. leontopetaloides tuber necessitate food technologies combinations to eliminate them. Further investigations are necessary to succeed in antinutrient levels alleviation in T. leontopetaloides tuber.

scholarly journals Phytolith Palaeoenvironments at Mumba Rock Shelter

2021 ◽  
Vol 9 ◽  
Author(s):  
Julio Mercader ◽  
Siobhán Clarke ◽  
Makarius Itambu ◽  
Abdallah Mohamed ◽  
Musa Mwitondi ◽  
...  
Keyword(s):  
Statistical Analysis ◽  
East Africa ◽  
Late Pleistocene ◽  
Principal Components ◽  
Stone Age ◽  
Later Stone Age ◽  
Rock Shelter ◽  
Shelter Site ◽  
Northern Tanzania ◽  
Plant Habitat

The rock shelter site of Mumba in northern Tanzania plays a pivotal role in the overall study of the late Pleistocene archaeology of East Africa with an emphasis on the Middle to Later Stone Age transition. We used phytolith analysis to reconstruct general plant habitat physiognomy around the site from the onset of the late Pleistocene to recent times, tallying 4246 individual phytoliths from 19 archaeological samples. Statistical analysis explored phytolith richness, diversity, dominance, and evenness, along with principal components to compare phytolith distributions over the site’s sequence with known plant habitats today. Generally, the phytolith record of Mumba signifies paleoenvironments with analogs in the Somalia – Masai bushland and grassland, as well as Zambezian woodlands.

scholarly journals Delimitation of flood areas based on a calibrated a DEM and geoprocessing: case study on the Uruguay River, Itaqui, southern Brazil

2019 ◽  
Vol 19 (1) ◽  
pp. 237-250 ◽  
Author(s):  
Paulo Victor N. Araújo ◽  
Venerando E. Amaro ◽  
Robert M. Silva ◽  
Alexandre B. Lopes
Keyword(s):  
Statistical Analysis ◽  
Flood Hazard ◽  
Satellite Image ◽  
Water Levels ◽  
Calibration Model ◽  
Southern Brazil ◽  
Temporal Series ◽  
Vertical Accuracy ◽  
High Flood ◽  
Uruguay River

Abstract. Flooding is a natural disaster which affects thousands of riverside, coastal, and urban communities causing severe damage. River flood mapping is the process of determining inundation extents and depth by comparing historical river water levels with ground surface elevation references. This paper aims to map flood hazard areas under the influence of the Uruguay River, Itaqui (southern Brazil), using a calibration digital elevation model (DEM), historic river level data and geoprocessing techniques. The temporal series of maximum annual level records of the Uruguay River, for the years 1942 to 2017, were linked to the Brazilian Geodetic System using geometric leveling and submitted for descriptive statistical analysis and probability. The DEM was calibrated with ground control points (GCPs) of high vertical accuracy based on post-processed high-precision Global Navigation Satellite System surveys. Using the temporal series statistical analysis results, the spatialization of flood hazard classes on the calibrated DEM was assessed and validated. Finally, the modeling of the simulated flood level was visually compared against the flood area on the satellite image, which were both registered on the same date. The free DEM calibration model indicated high correspondence with GCPs (R2=0.81; p<0.001). The calibrated DEM showed a 68.15 % improvement in vertical accuracy (RMSE = 1.00 m). Five classes of flood hazards were determined: extremely high flood hazard, high flood hazard, moderate flood hazard, low flood hazard, and non-floodable. The flood episodes, with a return time of 100 years, were modeled with a 57.24 m altimetric level. Altimetric levels above 51.66 m have a high potential of causing damage, mainly affecting properties and public facilities in the city's northern and western peripheries. Assessment of the areas that can potentially be flooded can help to reduce the negative impact of flood events by supporting the process of land use planning in areas exposed to flood hazard.

Effect of Moisture and Incubation Time on Ochratoxin A Production by an Isolate of Aspergillus ochraceus

1970 ◽  
Vol 53 (1) ◽  
pp. 89-91
Author(s):  
A F Schindler ◽  
Stanley Nesheim
Keyword(s):  
Statistical Analysis ◽  
Moisture Content ◽  
Ochratoxin A ◽  
Incubation Time ◽  
Maximum Yield ◽  
Water Levels ◽  
Aspergillus Ochraceus ◽  
Ambient Temperatures ◽  
Incubation Periods ◽  
Transfer Needle

Abstract Experiments were conducted to determine the culture requirements that would insure a probability of high ochratoxin production with a given isolate. Experiments at ambient temperatures (72 ± 2°F) determined the levels of the two most readily controlled variables, time and moisture content, during the growth of a high toxin-producing isolate (M298) of Aspergillus ochraceus. Tests were conducted in 2.8 L - Fernbach flasks containing 100 g shredded wheat and inoculated with spores on a transfer needle. Amounts of ochratoxin A/flask were determined by comparison against standards on TLC after chloroform extraction. Statistical analysis showed a relation between ochratoxin yield, water levels, and incubation periods. A water level of 40–70 ml/flask with an incubation period of 19-21 days at ambient temperatures should give a near to maximum yield of ochratoxin A.

scholarly journals Statistical Analysis of the Stability of Rock Slopes

2019 ◽  
Vol 7 (3) ◽  
pp. 60 ◽  
Author(s):  
Marcel van Gent ◽  
Ermano de Almeida ◽  
Bas Hofland
Keyword(s):  
Statistical Analysis ◽  
Physical Model ◽  
Model Tests ◽  
Water Levels ◽  
Test Series ◽  
Length Effect ◽  
Wave Flume ◽  
Physical Model Tests ◽  
Erosion Area ◽  
The Stability

Physical model tests were performed in a wave flume at Deltares with rock armoured slopes. A shallow foreshore was present. At deep water, the same wave conditions were used, but by applying different water levels, the wave loading on the rock armoured slopes increased considerably with increasing water levels. This allowed an assessment of the effects of sea level rise. Damage was measured by using digital stereo photography (DSP), which provides information on each individual stone that is displaced. Two test series were performed five times. This allowed for a statistical analysis of the damage to rock armoured slopes, which is uncommon due to the absence of statistical information based on a systematic repetition of test series. The statistical analysis demonstrates the need for taking the mean damage into account in the design of rock armoured slopes. This is important in addition to characterising the damage itself by erosion areas and erosion depths. The relation between damage parameters, such as the erosion area and erosion depth, was obtained from the tests. Besides tests with a straight slope, tests with a berm in the seaward slopes were also performed. A new method to take the so-called length effect into account is proposed to extrapolate results from physical model tests to real structures. This length effect is important, but is normally overlooked in the design of rubble mound structures. Standard deviations based on the presented model tests were used.

How We Can Use Multivariate Statistical Analysis to Predict Creasing of Fabrics

2014 ◽  
Vol 543-547 ◽  
pp. 1930-1933
Author(s):  
Katarína Zelová ◽  
Ludmila Fridrichová
Keyword(s):  
Statistical Analysis ◽  
Principal Components ◽  
Latent Variables ◽  
Analysis Method ◽  
Pca Analysis ◽  
Multivariate Statistical ◽  
Method Of Principal Components ◽  
Innovative Method ◽  
Component Loading

The creasing of textiles was evaluated by means of the innovative method of measuring the angle of recovery. Our aim is to find statistically significant features contributing to the determination of creasing materials. For this purpose, to identify the inner structures of data, the method of PCA analysis was used a method with latent variables. By means of PCA analysis (method of principal components) the original nine characteristics can be reduced to two latent variables, i.e. principal components. The structure and links among the examined features are characterized by methods like: Scree Plot, Score and component loading, Scatrerplot and Dendrogram.

scholarly journals Statistical Analysis and Trend Detection of the Hydrological Extremes of the Danube River at Bratislava

2021 ◽  
Vol 906 (1) ◽  
pp. 012101
Author(s):  
Veronika Bacová Mitková
Keyword(s):  
Statistical Analysis ◽  
Anthropogenic Activities ◽  
Water Levels ◽  
Danube River ◽  
Trend Detection ◽  
The Danube River ◽  
Natural Processes ◽  
The Past ◽  
Hydrological Extremes ◽  
Measured Water

Abstract The territory of the Danube River Basin is one of the most flood-endangered regions in Europe. The flow regime conditions of the Danube River are continually changing. These changes are the result of natural processes and anthropogenic activities. In the present study, we focused on the statistical analysis and trend detection of the hydrological extremes of the Danube River at Bratislava. This paper firstly analyses the changes in correlation between water levels of the Danube River at Bratislava and Kienstock. Studied period of 1991-2013 included one or three hour measured water levels of the Danube River at Bratislava and Kienstock and shorter periods (1991–1995, 1999–2002, and 2004—2013) were selected for identification of the water level changes at Bratislava. One of the factors that recall the necessity to establish empirical - regression relationships was increasing of water levels of the Danube River at Bratislava (due to sediments accumulation at Bratislava). The results of the analysis indicated an increasing of water levels corresponding to the same flood discharges observed in the past. We also can say that travel time of the Danube floods between Kienstock and Bratislava did not change significantly during the analysed period. In the second part of the paper, we have identified changes in commonly used hydrological characteristics of annual maximum discharges, annual discharges and daily discharges of the Danube River at Bratislava during the period of 1876–2019. We examined whether there is a significant trend in discharges of the Danube River at Bratislava.

Multivariate Statistical Analysis of Flat Vowel Spectra With a View to Characterizing Dysphonic Voices

2000 ◽  
Vol 43 (6) ◽  
pp. 1493-1508 ◽  
Author(s):  
Jean Schoentgen ◽  
Mounir Bensaid ◽  
Fabrizio Bucella
Keyword(s):  
Statistical Analysis ◽  
Principal Components ◽  
Multivariate Statistical Analysis ◽  
Heuristic Search ◽  
Vocal Tract ◽  
Multivariate Statistical ◽  
Magnitude Spectrum ◽  
Spectral Contour ◽  
Components Analysis ◽  
Different Levels

The aim of this article is to show how dysphonic voices can be characterized by means of a multivariate statistical analysis of flat vowel spectra. The spectral contour was obtained by means of a wavelet transform of the logarithmic magnitude spectrum, which was subsequently flattened to remove interspeaker variability related to the excitation and vocal tract filter functions. The results of the statistical analysis of flat spectra were the following. Firstly, principal components analysis produced markers that separated noisy from clean spectra. Secondly, the heuristic search for harmonic peaks or interharmonic dips could be omitted. Thirdly, conventional spectral markers of noise appeared as special instances of the markers that were derived statistically. Fourthly, the levels of visually assigned hoarseness and the first two principal components were significantly correlated. The assignment of different levels of (visual) hoarseness to different vowel timbres could be explained by the variability associated with the spectral contour.

Comparison of multivariate pattering methods in group/cluster identification regarding the science of educational research: Implicative Statistical Analysis vs. L’ Analysee Factorielle des Correspondances

2019 ◽  
Vol 6 (1) ◽  
pp. 238-245
Author(s):  
Sofia D Anastasiadou
Keyword(s):  
Statistical Analysis ◽  
Principal Components Analysis ◽  
Educational Research ◽  
Principal Components ◽  
Quantitative Research ◽  
Self Control ◽  
Clustering Methods ◽  
Technological Education ◽  
Cluster Identification ◽  
Components Analysis

Nowadays, there is a substantial improvement and utilisation of pattering methods in the science of educational research, a comparison of multivariate methods in group/cluster identification in the scientific domain of quantitative research has not been carried out. This study analyses two different statistical techniques: i.e., the principal components analysis (PCA) and the implicative statistical analysis (ASI). A survey was carried out using a structured questionnaire for a sample of 135 nurses which studied in the School of Pedagogical and Technological Education in order to be qualified in respect The study focuses on the presentation of the two main types of clustering methods, της ASI and L’ Analysee Factorielle des Correspondances (AFC). AFC’s results made it evident that Emotionality, Self-control, Sociability, General items of EI constructs are shaped attitudes and reveal the latent dimension of respondents psychological attributes related to EI conceptual constructs. Keywords: L’ Analysee Factorielle des Correspondances, principal components analysis, implicative statistical analysis, research.

scholarly journals Biodegradation of cyanide using recombinant Escherichia coli expressing Bacillus pumilus cyanide dihydratase

2020 ◽  
Vol 22 (1) ◽  
pp. 27-35
Author(s):  
Aram Joel Panay ◽  
Claudia Liliana Vargas-Serna ◽  
Maria Lorena Carmona-Orozco
Keyword(s):  
Enzymatic Degradation ◽  
Elevated Temperatures ◽  
Attractive Alternative ◽  
Free Cyanide ◽  
Chemical Methods ◽  
Intracellular Enzyme ◽  
Industrial Sample ◽  
Whole Cells ◽  
E Coli ◽  
Cyanide Dihydratase

Despite its high toxicity, cyanide is used in several industrial processes, and as a result, large volumes of cyanide wastewater need to be treated prior to discharge. Enzymatic degradation of industrial cyanide wastewater by cyanide dihydratase, which is capable of converting cyanide to ammonia and formate, is an attractive alternative to conventional chemical methods of cyanide decontamination. However, the main impediment to the use of this enzyme for the biodegradation of cyanide is the intolerance to the alkaline pH at which cyanide waste is kept and its low thermoresistance. In the present study, the catalytic properties of whole E. coli cells overexpressing a cyanide dihydratase gene from B. pumilus were compared to those of the purified enzyme under conditions similar to those found in industrial cyanide wastewater. In addition, the capacity of whole cells to degrade free cyanide in contaminated wastewater resulting from the gold mining process was also determined. The characteristics of intracellular enzyme, relative to purified enzyme, included increased thermostability, as well as greater tolerance to heavy metals and to a lesser extent pH. On the other hand, significant enzymatic degradation (70%) of free cyanide in the industrial sample was achieved only after dilution. Nevertheless, the increased thermostability observed for intracellular CynD suggest that whole cells of E. coli overexpressing CynD are suited for process that operate at elevated temperatures, a limitation observed for the purified enzyme.

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