scholarly journals Thermogravimetric Analysis of Modified Montmorillonite Clay for Mycotoxin Decontamination in Cereal Grains

2020 ◽  
Vol 2020 ◽  
pp. 1-5
Author(s):  
Bunmi K. Olopade ◽  
Obinna C. Nwinyi ◽  
Joseph A. Adekoya ◽  
Isiaka A. Lawal ◽  
Olushola A. Abiodun ◽  
...  
Keyword(s):  
Weight Loss ◽  
Thermogravimetric Analysis ◽  
Nonparametric Test ◽  
Montmorillonite Clay ◽  
Cymbopogon Citratus ◽  
The Third ◽  
Significant Difference ◽  
Degradation Step ◽  
The Stability ◽  
Lemongrass Essential Oil

Thermogravimetric analysis (TGA) was carried out to study the stability of nanoformulations used for the decontamination of mycotoxins. The TGA patterns of the nanoformulations from montmorillonite clay and Cymbopogon citratus (lemongrass) extracts were assessed with temperature ranging from ambient (20°C) to 1000°C. The various nanoformulations studied included unmodified montmorillonite clay (Mont), montmorillonite washed with sodium chloride (Mont-Na), montmorillonite mixed with lemongrass essential oil (Mont-LGEO), and montmorillonite mixed with an equal quantity of lemongrass powder (Mont-LGP). There was no significant difference in the median of the various nanoformulations within 4 weeks at p < 0.05 using the Kruskal–Wallis nonparametric test. For the TGA, the first degradation for montmorillonite clay and the nanoformulations occurred at a temperature between 80 and 101°C and was attributed to the loss of lattice water outside the coordination sphere with a range of 3.5–6.5% weight loss. The second degradation occurred within the temperature of 338 to 344°C, and the third, at a temperature between 640 and 668°C for Mont and the formulations of Mont-Na, Mont-LGEO, and Mont-LGP. There were strong similarities in the degradation patterns of Mont and Mont-Na with the minimum difference being the relatively higher weight loss of the sodium-exchanged cation for Mont-Na at the third degradation step. Hence, the order of stability from the most resistant to the least resistant to degradation is as follows: Mont-LGEO ≥ Mont-Na ≥ Mont ≥ Mont-LGP.

scholarly journals Chemical, Mineralogical, and Refractory Characterization of Kaolin in the Regions of Huayacocotla-Alumbres, Mexico

2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
L. M. Romero-Guerrero ◽  
R. Moreno-Tovar ◽  
A. Arenas-Flores ◽  
Y. Marmolejo Santillán ◽  
F. Pérez-Moreno
Keyword(s):  
Thermogravimetric Analysis ◽  
Decomposition Temperature ◽  
X Ray Diffraction ◽  
Polarization Optical Microscopy ◽  
Plagioclase Feldspar ◽  
X Ray ◽  
Mullite Phase ◽  
Significant Difference ◽  
The Stability

In the present work, the chemical, mineralogical, refractory, and microstructural characterizations of kaolinites from the Huayacocotla-Alumbres region, which is between Veracruz and Hidalgo border, by X-ray diffraction (XRD), polarization optical microscopy (POM), scanning electron microscopy (SEM), refractoriness proof (pyrometric cone equivalent), and thermogravimetric analysis (TGA) were carried out. The analysis by POM showed that the kaolinization degree in this region is variable due to the presence of primary minerals, such as plagioclase, feldspar, and quartz. Additionally, hydrothermal alteration of the epithermal type was determined by oxidation of sulfides (pyrite and galena) and chlorite association. With the X-ray diffraction technique, andalusite and kaolinite were identified as the majority phases in Huayacocotla and quartz was identified as the majority phase in Alumbres. The minority phases, such as dickite, kaolinite, and cristobalite, were observed in both zones. The SEM technique was useful in the determination of the morphology of kaolinite and impurities of Na, Mg, K, and Fe of the complex clay illite-andalusite-dickite group. Thermogravimetric analysis was useful to discover the decomposition temperature and reveal the significant difference between 400 and 800°C, which showcases the greatest mass loss due to dehydration and carbonates decomposition. The mullite phase was detected at approximately 1000°C in the kaolin samples. The refractoriness tests were important to determine the stability temperature of kaolin, which is between 1300 and 1600°C. This stability temperature makes it feasible to use the kaolin as a refractory material for both low and high temperatures. The variables that affect the kaolin stability temperature were determined by principal components with the XLSTAT free program.

scholarly journals Efeito potencializador do Cymbopogon citratus-Stapf sobre a ação da acetilcolina na contratilidade de músculo liso

1989 ◽  
Vol 11 (11) ◽  
pp. 83
Author(s):  
Ana Maria Külzer ◽  
Amauri Rodrigues da Silva ◽  
Zuleica Tabarelli
Keyword(s):  
Smooth Muscle ◽  
First Record ◽  
Physiological Solution ◽  
Male Rats ◽  
Tyrode Solution ◽  
Cymbopogon Citratus ◽  
The Third ◽  
Significant Difference ◽  
Functional Nature ◽  
Male Wistar Rats

Authors searched actions of Cymbopogon citratus-Stapf aquous extract, 2% concentration, on montility of smooth muscle. It were performed 10 (ten) experiments, each of them consisted of the motility record of a segment of duodenum from male Wistar rats maintained in a Tyrode solution water-bath to isolated organ. Physiological parameters (temperature, pH, oxigen supply) were controled to obtain the functional nature of organ motility. It were realized three records to each experiment in this sequency:           First record: control record (standard) from motility of duodenum smooth muscle in Tyrode bath.           Second record: after addition of 0,5 ml physiological solution before the third record, the bath liquid was entirely substituted and the organ was washed tith Tyrode solution.            Third record: after 15 (fifteen) minutes from the addition of Cymbopogon citratus-Stapf tea 2% concentration, it was add 0,5ml acetylcholine solution (11,8165 Mg in 50 ml physiological solution).It was verified that it shows a significant difference between 2nd and third record groups compared whit control records (first record groups) on smooth muscle motility of isolated duodenum from Wistar male rats.

scholarly journals Encapsulation efficiency and thermal stability of lemongrass (Cymbopogon citratus) essential oil microencapsulated by the spray-drying process

Food Research ◽  
2020 ◽  
Vol 5 (1) ◽  
pp. 195-202
Author(s):  
P.T.N. Nguyen ◽  
T.T. Vo ◽  
T.Y.N. Tran ◽  
T.H.N. Le ◽  
H.C. Mai ◽  
...  
Keyword(s):  
Essential Oil ◽  
Spray Drying ◽  
Treatment Time ◽  
Heating Temperature ◽  
Core Material ◽  
Wall Material ◽  
Cymbopogon Citratus ◽  
Liquid Form ◽  
The Stability ◽  
Lemongrass Essential Oil

Encapsulation is a potential technique that is widely studied and applied in the preservation of biological compounds and living cells. Lemongrass (Cymbopogon citratus) essential oil is a biological compound that emits a strong aroma and contains robust antibacterial compounds, hence its applications in various areas such as food, pharmaceuticals and cosmetics. However, lemongrass essential oil is in a liquid form, so it is easy to evaporate and oxidize when being exposed to temperature variations, oxygen, and light. Hence, the present study was aimed to determine the effects of heating temperature and time on the stability of microencapsulated lemongrass essential oil powder. In this research, microencapsulated powder was produced by the spray-drying method using maltodextrin (30%, w/w) as the wall material and lemongrass (1.5%, w/w) as the core material. Thereafter, the effects of heat during processing, including temperature (60°C to 180°C) and treatment time (from 20 to 80 mins) were evaluated. The results showed that when the temperature and the time increased, the color of powder became darker and OR values were rapidly reduced. The selected optimal temperature and time was 100°C and 20 mins. The encapsulated essential oil maintained its main components including nerol, citral a, citral b, and geraniol, even after being heated.

scholarly journals Perbandingan randemen minyak atsiri sereh (cymbopogon citratus) yang umur panennya 6 bulan Dan 9 bulan dengan metode destilasi air)

2019 ◽  
Vol 10 (3) ◽  
pp. 66-71
Author(s):  
Rani Prabandari
Keyword(s):  
Essential Oil ◽  
Soil Fertility ◽  
Essential Oils ◽  
Test Sample ◽  
Distillation Method ◽  
Average Yield ◽  
Cymbopogon Citratus ◽  
Water Distillation ◽  
Significant Difference ◽  
Lemongrass Essential Oil

AbstractIndonesian nature is very rich in plants containing essential oils. Essential oils can be produced from various parts of plants such as roots, stems, leaves, flowers, or fruit. There are 50-200 species of essential oil producing plants. In Indonesia there are around 40 types of essential oils producing plants. One of the essential oils producing plants is lemongrass (Taufiq, Tuhana, 2008 p: 2). This study aims to determine the comparison of essential oils in Lemongrass (Cymbopogon citratus) which are harvested at 6 months and 9 months with a water distillation method. The procedure for selecting samples and research samples, directly with the object of research, is the citronella plant whose harvest age is 6 months taken from 1 clump and 9 months taken from 1 clump. The results of this study indicate that lemongrass plants with a harvest age of 6 months produce more essential oils compared to lemongrass plants with a harvest age of 9 months. This is influenced by several factors, including climate, harvest age. Lemongrass plants aged 6 months are the optimal age to be harvested, so that they get a higher yield of essential oils, besides that the factors of soil fertility and the intensity of sunlight also affect the content of essential oils of lemongrass.From the results of the research that has been done on the test sample, it can be concluded that the results of the essential oil ration on citronella (Cymbopogon citratus), which has 6 months of harvest age, obtained an average yield of 0.46% v / b and 9 months. 0.35% v / b with the results of the t-test obtained by the price t-count (2.984)> t-table (2.776). So that H0 is rejected and Ha is accepted and it can be concluded that there is a significant difference between lemongrass with 6 months and 9 months of harvest. Keywords: lemongrass, essential oil, age of harvest, water distillation

Thermogravimetric Analysis of Dentin

1972 ◽  
Vol 51 (2) ◽  
pp. 509-514 ◽  
Author(s):  
J.J. Lim ◽  
A.R. Liboff
Keyword(s):  
Weight Loss ◽  
Thermogravimetric Analysis ◽  
Tricalcium Phosphate ◽  
Activation Energies ◽  
Zero Order ◽  
The Third

Four peaks were observed in the differential primary weight loss with temperatures up to 1,000 C. The first and second peaks correspond to the loss of water and the volatilization of protein. The third peak results from the carbonate. The fourth peak, which occurs at 700 to 800 C, probably is related to the transformation of hydroxyapatite to β-tricalcium phosphate. A zero order of reaction was assumed, and the activation energies in vacuum were determined to be 10.2 and 12.5 kcal/mol for loss of water and protein, respectively.

Stability and mutual impact of perception of parental pressure and infants' social support – A study based on the difference between employment status and household income

2021 ◽  
pp. 002072092199705
Author(s):  
Yong Wang
Keyword(s):  
Household Income ◽  
Employment Status ◽  
Working Mothers ◽  
Social Research ◽  
Research Report ◽  
Parental Pressure ◽  
Income Levels ◽  
Significant Difference ◽  
The Difference ◽  
The Stability

The purpose of this study is to explore the stability and interaction between parental pressure and social research report, as well as the role of employment status and family income levels in this process. This study used a special study on Korean children (PSKC) 2–4 waves. Use t-test, correlation and autoregressive cross-delay modeling to analyze the data. The main findings of this study are: First, over time, parental pressure and mother’s social research report are consistent. Secondly, the pressure of motherhood and childcare has an obvious lagging effect on upbringing, and vice versa. Third, there is no significant difference between working mothers and non-working mothers in terms of the stability of working parents' pressure, social research report and social research report for children's pressure channels. However, parental pressure can only predict the social research report of working mothers. Fourth, there is no significant difference between the stability and interaction of these two structures in household income levels. In short, the results show that, over time, parental pressure is consistent with mother’s social research report. The results also show that there is a significant cross-lag effect between the mothers’ perceptions of mutual pressure analysis. In the process from parental pressure to social research report, I found the difference between working and non-working mothers. The advantage of this study is that the expected longitudinal design was adopted during infancy and the priority between the two structures can be considered. The results of this study can be used as a source of intervention plans to help parents withstand severe parenting pressure and lack of social research report.

scholarly journals Publication activity of chief and consultant general/visceral surgeons in German university hospitals—a ten-year analysis

2021 ◽  
Author(s):  
Eva C. Böckmann ◽  
E. S. Debus ◽  
R. T. Grundmann
Keyword(s):  
Impact Factor ◽  
Publication Activity ◽  
University Hospitals ◽  
Cumulative Impact ◽  
University Departments ◽  
The Third ◽  
Publication Number ◽  
Significant Difference ◽  
The Mean ◽  
Number Of Publications

Abstract Purpose The publication activity of 38 German general/visceral surgery university departments, documented by first or last authorship from staff surgeons (chief and consultants), was evaluated. Methods The observation period extended from 2007 to 2017 and all PubMed-listed publications were considered. Impact factor (IF) was evaluated through the publishing journal’s 5-year IF in 2016, as was the IF for each individual publication. Ranking was expressed in quartiles. Results The staff surgeons of the 38 departments comprised 442 surgeons, of which only 351 (79.4%) were active as first or last authors. Four thousand six hundred and ninety-nine publications published in 702 journals were recorded. The four leading departments in publication number published as much as the last 20 departments (1330 vs. 1336 publications, respectively). The mean of the first (most active) department quartile was 19.6 publications, the second 15.4, the third 11.0, and the last quartile 7.6 per publishing surgeon. The total cumulative impact factor was 14,130. When examining the mean number of publications per publishing surgeons per the 10 year period, the mean of the first quartile was 57.9 cumulative IF, the second 45.0, the third 29.5, and the fourth quartile 17.1. With 352 (7.5%) publications, the most frequently used journal was Chirurg, followed by Langenbeck’s Archives of Surgery with 274 (5.8%) publications. Pancreas-related topics led in terms of publication number and IF generated per individual publication. Conclusion A significant difference in publication performance of individual departments was apparent that cannot be explained by staff number. This indicates that there are as yet unknown factors responsible for minor publication activity in many university departments.

scholarly journals Phenotypic Detection of Carbapenemase Production in Carbapenem-Resistant Enterobacteriaceae by Modified Hodge Test and Modified Strip Carba NP Test

2021 ◽  
Author(s):  
Nisha Patidar ◽  
Nitya Vyas ◽  
Shanoo Sharma ◽  
Babita Sharma
Keyword(s):  
Carbapenem Resistance ◽  
Nonparametric Test ◽  
Multidrug Resistant ◽  
Clinical Samples ◽  
Chi Square ◽  
Carbapenem Resistant ◽  
The Social ◽  
Significant Difference ◽  
High Degree ◽  
Carbapenem Resistant Enterobacteriaceae

Abstract Objective Carbapenems are last resort antibiotics for multidrug-resistant Enterobacteriaceae. However, resistance to carbapenem is increasing at an alarming rate worldwide leading to major therapeutic failures and increased mortality rate. Early and effective detection of carbapenemase producing carbapenem-resistant Enterobacteriaceae (CRE) is therefore key to control dissemination of carbapenem resistance in nosocomial as well as community-acquired infection. The aim of present study was to evaluate efficacy of Modified strip Carba NP (CNP) test against Modified Hodge test (MHT) for early detection of carbapenemase producing Enterobacteriaceae (CPE). Material and Methods Enterobacteriaceae isolated from various clinical samples were screened for carbapenem resistance. A total of 107 CRE were subjected to MHT and Modified strip CNP test for the detection of CPE. Statistical Analysis It was done on Statistical Package for the Social Sciences (SPSS) software, IBM India; version V26. Nonparametric test chi-square and Z-test were used to analyze the results within a 95% level of confidence. Results Out of 107 CRE, 94 (88%) were phenotypically confirmed as carbapenemase producer by Modified strip CNP test and 46 (43%) were confirmed by Modified Hodge Test (MHT). Thirty-eight (36%) isolates showed carbapenemase production by both MHT and CNP test, 56 isolates (52%) were CNP test positive but MHT negative, eight (7%) isolates were MHT positive but CNP test negative and five (5%) isolates were both MHT and CNP test negative. There is statistically significant difference in efficiency of Modified CNP test and MHT (p < 0.05). Conclusion Modified strip CNP test is simple and inexpensive test which is easy to perform and interpret and gives rapid results in less than 5 minutes. It has high degree of sensitivity and specificity. Modified strip CNP test shows significantly higher detection capacity for carbapenemase producers as compared with MHT.

scholarly journals Is duodeno-jejunal bypass liner superior to pylorus preserving bariatric surgery in terms of complications and efficacy?

2021 ◽  
Author(s):  
Istvan Bence Balint ◽  
Ferenc Csaszar ◽  
Krisztian Somodi ◽  
Laszlo Ternyik ◽  
Adrienn Biro ◽  
...  
Keyword(s):  
Bariatric Surgery ◽  
Weight Loss ◽  
Surgical Procedures ◽  
Risk Level ◽  
Jejunal Mucosa ◽  
Complication Rates ◽  
Pubmed Database ◽  
Significant Difference ◽  
Weight Loss Outcomes ◽  
Jejunal Bypass

Abstract Purpose Based on recent scientific evidence, bariatric surgery is more effective in the management of morbid obesity and related comorbidities than conservative therapy. Pylorus preserving surgical procedures (PPBS) such as laparoscopic single-anastomosis duodeno-jejunal or duodeno-ileal bypass with sleeve gastrectomy are modified duodenal switch (DS) surgical techniques. The duodeno-jejunal bypass liner (DJBL) is a novel surgical method in the inventory of metabolism focused manual interventions that excludes duodeno-jejunal mucosa from digestion, mimicking DS procedures without the risk of surgical intervention. The aim of this article is to summarize and compare differences between safety-related features and weight loss outcomes of DJBL and PPBS. Methods A literature search was conducted in the PubMed database. Records of DJBL-related adverse events (AEs), occurrence of PPBS-related complications and reintervention rates were collected. Mean weight, mean body mass index (BMI), percent of excess of weight loss (EWL%), percent of total weight loss (TWL%) and BMI value alterations were recorded for weight loss outcomes. Results A total of 11 publications on DJBL and 6 publications on PPBS were included, involving 800 and 1462 patients, respectively. The baseline characteristics of the patients were matched. Comparison of DJBL-related AEs and PPBS-related severe complications showed an almost equal risk (risk difference (RD): −0.03 and confidence interval (CI): −0.27 to 0.21), despite higher rates among patients having received endoscopic treatment. Overall AE and complication rates classified by Clavien-Dindo showed that PPBS was superior to DJBL due to an excess risk level of 25% (RD: 0.25, CI: 0.01–0.49). Reintervention rates were more favourable in the PPBS group, without significant differences in risk (RD: −0.03, CI: −0.27 to 0.20). However, PPBS seemed more efficient regarding weight loss outcomes at 1-year follow-up according to raw data, while meta-analysis did not reveal any significant difference (odds ratio (OR): 1.08, CI: 0.74–1.59 for BMI changes). Conclusion Only limited conclusions can be made based on our findings. PPBS was superior to DJBL with regard to safety outcomes (GRADE IIB), which failed to support the authors’ hypothesis. Surgical procedures showed lower complication rates than the incidence of DJBL-related AEs, although it should be emphasized that the low number of PPBS-related mild to moderate complications reported could be the result of incomplete data recording from the analysed publications. Weight loss outcomes favoured bariatric surgery (GRADE IIB). As the DJBL is implanted into the upper gastrointestinal tract for 6 to 12 months, it seems a promising additional method in the inventory of metabolic interventions.

Optimization of Organic Fibres%[Kevlar/Arobocel/Acrylic] in NAO Brake Pad Application and its Effect on Thermal Stability & Friction Characteristics

2012 ◽  
Vol 531-532 ◽  
pp. 8-12
Author(s):  
M.A. Sai Balaji ◽  
K. Kalaichelvan
Keyword(s):  
Thermal Stability ◽  
Weight Loss ◽  
Minimum Weight ◽  
Friction Material ◽  
Brake Pad ◽  
Temperature Zone ◽  
Good Thermal Stability ◽  
Friction Testing ◽  
Brake Application ◽  
The Stability

Organic fibres (Kevlar/ Arbocel / Acrylic) have good thermal stability, higher surface area and bulk density. The optimization of organic fibres percentage for thermal behaviour is considered using TGA. The temperature raise during brake application will be between 150-4000 C and this temperature zone is very critical to determine the fade characteristics during friction testing. Hence, three different friction composites are developed with the same formulation varying only the Kevlar, Arbocel and Acrylic fibres which are compensated by the inert filler namely the barites and are designated as NA01, NA02 and NA03 respectively. After the fabrication, the TGA test reveals that the composite NA03 has minimum weight loss. The friction coefficient test rig is then used to test the friction material as per SAE J661a standards. The results prove that the brake pad with minimum weight loss during TGA has higher friction stability. Thus, we can correlate the thermal stability with the stability of friction.

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