scholarly journals Influential Factors and Determination of strength of in-situ concrete, using twist-off method.

2019 ◽  
Vol 7 (2) ◽  
Author(s):  
Pooria Najarbashi ◽  
Mahmoud Naderi
Keyword(s):  
Low Cost ◽  
Concrete Strength ◽  
Influential Factors ◽  
Laboratory Methods ◽  
Significant Difference ◽  
Site Evaluation ◽  
In Situ Methods ◽  
Very High

Concrete strength represents by far the most critical property of concrete. It represents the mechanical properties of concrete. On-site evaluation of concrete strength remains the fundamental challenge in the condition assessment of existing infrastructure. Although standard laboratory methods can be typically used but most of these testing methods are costly and time-consuming. Among the in-situ methods, the “twist-off ” method with very slight damage is genuinely a convenient, fast and also low-cost technique that provides accurate results for engineers. In this study, the twist-offmethod has been used for the assessment of in-situ strength of the 30 concrete structures in Qazvin in Iran. The results showed structures studied had a strength of 45 to 600 kg/cm2 and the average is about 200 kg/cm2. The observed variation is very high, as well as a significant difference between the compressive strength of the columns, and the floors of the buildings that all indicate non-standard concrete mixing and inadequate control over construction. However, according to the past experience and results of the samples, some recommendations in this regard have been suggested.

scholarly journals Development and application of a portable instrument for drugs analysis in pharmaceutical preparations

2015 ◽  
Vol 51 (3) ◽  
pp. 699-708
Author(s):  
Paulo Roberto da Silva Ribeiro ◽  
Helena Redigolo Pezza ◽  
Leonardo Pezza ◽  
Liliane Spazzapam Lima ◽  
Matthieu Tubino
Keyword(s):  
Low Cost ◽  
Pharmaceutical Preparations ◽  
Pharmaceutical Products ◽  
Ammonium Molybdate ◽  
Quantitative Studies ◽  
Significant Difference ◽  
Drugs Analysis ◽  
And Performance

This article describes the application and performance of an inexpensive, simple and portable device for colorimetric quantitative determination of drugs in pharmaceutical preparations. The sensor is a light detector resistor (LDR) incorporated into a black PTFE cell and coupled to a low-cost multimeter (Ohmmeter). Quantitative studies were performed with captopril/p-chloranil/H2O2 and methyldopa/ammonium molybdate systems. Calibration curves were obtained by plotting the electrical resistance of the LDR against the concentration of the colored species in the ranges 1.84 × 10-4 to 1.29 × 10-3mol L-1 and 5.04 × 10-4 to 2.52 × 10-3 mol L-1 for captopril/p-chloranil/H2O2 and methyldopa/ammonium molybdate systems, respectively, exhibiting good coefficients of determination. Statistical analysis of the results obtained showed no significant difference between the proposed methodologies and the official reported methods, as evidenced by the t-test and variance ratio at a 95% confidence level. The results of this study demonstrate the applicability of the instrument for simple, accurate, precise, fast,in situ and low-cost colorimetric analysis of drugs in pharmaceutical products.

scholarly journals DETERMINATION OF MECHANICAL PROPERTIES OF REPAIR MORTARS USING IN SITU METHODS UNDER DIFFERENT CURINGS

2020 ◽  
Vol 2 ◽  
pp. 3-18
Author(s):  
Ali Saberi Varzaneh ◽  
Mahmoud Naderi
Keyword(s):  
Mechanical Properties ◽  
Concrete Structures ◽  
High Impact ◽  
Physical Factors ◽  
High Confidence ◽  
In Situ Methods ◽  
Repair Mortars ◽  
Friction Transfer

Considering the differences between environmental conditions of concrete structures and laboratory conditions, it is important to determine the parameters of the materials at the site of the structure. One of these materials is cement-based repair mortars due to the damage of concrete structures that may arise due to chemical or physical factors, these structures are required to be repaired. For this reason, in this paper, to determine the strength of repair mortars of different ages and under different Curing, Situ methods "Friction-Transfer" and "Pull-off" were used and the relationships between the Flexural Compressive, Tensile and readings obtained from the above methods on cementations mortars are presented. Experiments were performed on mortars at ages 3, 7, 28, 42 and 90 days under the conditions of "waterlogging", "Curing Agent" and "releasing in the outdoor". The results show the high impact of the process on the Flexural Compressive, Tensile of the repair mortars and the results of the "Friction-Transfer" and "Pull-off" methods. Also, a high correlation coefficient was obtained between the mechanical properties of the mortars and the results of the above tests; it is possible to measure the mechanical properties of repair mortars in situ with high confidence and in situ

scholarly journals A Simple, Rapid, Fluorometric Assay for Dopamine by In Situ Reaction of Boronic Acids and cis-Diol

2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Xiaoxia Liu ◽  
Miaomiao Tian ◽  
Wenmei Gao ◽  
Jinzhong Zhao
Keyword(s):  
Low Cost ◽  
Boronic Acids ◽  
Emission Peak ◽  
Excitation Wavelength ◽  
Fluorescence Sensing ◽  
Serum Samples ◽  
Turn On ◽  
Rapid Reaction

An efficient, sensitive, and low-cost method has been developed for turn-on fluorescence sensing of dopamine (DA). The method relies on the rapid reaction of DA and 3-Hydroxyphenylboronic acid (3-HPBA) via specific recognition between boronic acids and cis-diol of DA in alkaline solution. The reaction product shows an excitation wavelength of 417 nm and the maximum emission peak at 470 nm. The proposed method allows the determination of DA in the range of 50 nM–25 μM, and the whole detection can be completed within 5 minutes. Furthermore, the presented approach has good selectivity and has been successfully applied to DA sensing in human serum samples, showing great potential in clinical diagnosis.

scholarly journals Orexitropic Signaling Proteins in Obese Children

2007 ◽  
Vol 7 ◽  
pp. 1263-1271 ◽  
Author(s):  
Ljiljana Saranac ◽  
Bojko Bjelakovic ◽  
Hristina Stamenkovic ◽  
Borislav Kamenov
Keyword(s):  
Body Mass ◽  
Central Obesity ◽  
Energy Homeostasis ◽  
Leptin Resistance ◽  
Signaling Proteins ◽  
Obese Children ◽  
Significant Difference ◽  
The Mean ◽  
Very High

Adipose tissue is not only the main organ for energy storage, but it also has endocrine properties, producing “adipokines” responsible for energy homeostasis, insulin sensitivity, and inflammation. Leptin, produced by adipocytes, is the key hormone in appetite regulation and suppression of orexigenic, hypothalamic neuropeptide Y (NPY). We wanted to establish and compare levels of leptin and NPY in different obesity types in childhood, and to investigate their correlations with auxological parameters. Twenty-one obese children (seven girls and 14 boys), divided into two groups, were compared with 14 controls. The mean age of the study group was 10.81 ± 3.69 years and the mean puberty stage was 2.21. The mean body mass index (BMI) was 32.80 kg/m2(range 23.30– 47.02) and the mean overweight 30.73 kg (range 8.00–74.00). The mean leptin level was higher in boys and in the group with central obesity, but was not significant. Leptin/NPY ratio and leptin/BMI ratio was also higher in the central obesity group and there was a more significant difference compared with controls. We found significant correlation of the leptin level with body mass (BM), body mass excess (BME), and BMI (p < 0.05). The mean leptin level in obese children was very high (36.39 ng/ml). Leptin and NPY levels showed inverse values in two different obesity types. Results are suggestive for leptin resistance rather than leptin deficiency in our group of obese children. Orexitropic signaling proteins correlated significantly with auxological parameters. Determination of the leptin and NPY concentrations provided evidence that obesity represents disease with neuroendocrine dysfunction and high leptin/NPY ratio, which could be a useful marker for central obesity.

Impact of Cytogenetic Abnormalities On Outcome Among Patients with Relapsed/Refractory Multiple Myeloma Treated with Bortezomib: Adverse Effect of 1q21 (CKS1B) Amplification.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 2826-2826
Author(s):  
Hong Chang ◽  
Young Trieu ◽  
Connie Qi ◽  
Wei Xu ◽  
Donna E. Reece
Keyword(s):  
High Risk ◽  
Genetic Factors ◽  
Objective Response ◽  
Cytogenetic Abnormalities ◽  
Significant Difference ◽  
Variate Analysis ◽  
Ortho Biotech ◽  
Duration Of Response

Abstract Abstract 2826 Poster Board II-802 To investigate whether genetic risk factors affect the outcome of relapsed/refractory myeloma patients undergoing bortezomib therapy, we evaluated the clinical features of 85 patients treated with bortezomib and correlated with the high-risk cytogenetic abnormalities as detected by interphase cytoplasmic fluorescence in situ hybridization (cIg-FISH). Forty (47%) patients had an objective response to bortezomib with median progression free (PFS) and overall survivals (OS) of 9.4 and 12.6 months, respectively. cIg-FISH determination of del(13q), del(17p), del(1p21), t(4;14), and amp. (1q21)(CKS1B) was done on 79, 77, 77, 78, and 80 cases and the frequency of their detection was 38%, 22%, 26%, 18%, and 39%, respectively. There was no statistically significant difference in terms of response or duration of response to bortezomib for patients with or without any of the cytogenetic abnormalities. PFS was also comparable among patients with and without the aforementioned genetic markers. However, patients with 1q21(CKS1B) amplification had significantly shorter OS than those without such abnormality (5.3 vs. 24.6 months, p=0.0005). Multi-variate analysis adjusting for all 5 high-risk genetic factors confirmed that 1q21(CKS1B) amplification is an independent risk factor for OS (p=0.008). Improved therapeutic strategies may be required for this subgroup of patients. Disclosures: Reece: Ortho Biotech: Honoraria, Research Funding.

In-situ methods for the determination of current distributions in PEM fuel cells

1998 ◽  
Vol 43 (24) ◽  
pp. 3773-3783 ◽  
Author(s):  
Jürgen Stumper ◽  
Stephen A. Campbell ◽  
David P. Wilkinson ◽  
Mark C. Johnson ◽  
Mike Davis
Keyword(s):  
Fuel Cells ◽  
Pem Fuel Cells ◽  
Current Distributions ◽  
In Situ Methods

Arterial occlusion versus isofiltration pulmonary capillary pressures during very high flow

1987 ◽  
Vol 62 (3) ◽  
pp. 1174-1178 ◽  
Author(s):  
Z. Bshouty ◽  
J. Ali ◽  
M. Younes
Keyword(s):  
Arterial Occlusion ◽  
Longitudinal Distribution ◽  
Pulmonary Flow ◽  
Pulmonary Capillary ◽  
Effective Filtration Pressure ◽  
Significant Difference ◽  
Occlusion Technique ◽  
Capillary Pressures ◽  
Very High

Pressure in the compliant middle segment of the pulmonary vascular bed (PM), as determined by arterial occlusion, was compared with pressure at the filtration site (effective filtration pressure, EFP), determined by the isofiltration technique, at very high (7–10 times normal) pulmonary flow in six in situ perfused canine left upper lobes. At these flow rates inflow and left atrial pressures averaged 41.9 +/- 1.3 and 2.5 +/- 0.5 (SE) mmHg, respectively. PM was 30.9 +/- 1.6 mmHg, and EFP was 32.3 +/- 1.9 mmHg with no significant difference between the two measurements by paired t test. The results indicate that the arterial occlusion technique yields a pressure that is equivalent to EFP even during very high pulmonary blood flow where the longitudinal distribution of resistance is quite different from that obtained during normal flow.

scholarly journals In Situ Determination of Urea in Milk Employing a Portable and Low-Cost LED Photometer

2017 ◽  
Vol 11 (4) ◽  
pp. 1149-1154
Author(s):  
Willian Toito Suarez ◽  
Benedito Roberto de Alvarenga Junior ◽  
Mathews de Oliveira Krambeck Franco ◽  
Wesley Lira Gabriel ◽  
Denílson Mendes de Oliveira ◽  
...  
Keyword(s):  
Low Cost ◽  
Led Photometer

scholarly journals Validation of a UV-spectrophotometric analytical method for determination of LPSF/AC04 from inclusion complex and liposomes

2015 ◽  
Vol 51 (1) ◽  
pp. 183-191
Author(s):  
Rafaela Siqueira Ferraz ◽  
Elisângela Afonso Moura Mendonça ◽  
Jéssica Priscila Avelino Silva ◽  
Isabella Macário Ferro Cavalcanti ◽  
Mariane Cajubá Britto Lira-Nogueira ◽  
...  
Keyword(s):  
Inclusion Complex ◽  
Spectrophotometric Method ◽  
Analytical Method ◽  
Low Cost ◽  
Health Surveillance ◽  
Validation Parameters ◽  
Significant Difference ◽  
Detection And Quantification ◽  
Sensitive Spectrophotometric Method

The aim of this study was to develop and validate a UV spectrophotometric method for determination of LPSF/AC04 from inclusion complex and encapsulated into liposomes. The validation parameters were determined according to the International Conference on Harmonisation (ICH) and National Health Surveillance Agency (ANVISA) guidelines. LPSF/AC04 was determined at 250 nm in methanol by a UV spectrophotometric method, exhibiting linearity in the range from 0.3 to 2 µg.mL−1 (Absorbance=0.18068 x [LPSF/AC04 µg.mL-1] + 0.00348), (r2=0.9995). The limits of detection and quantification were 0.047µg.mL−1 and 0.143µg.mL−1, respectively. The method was accurate, precise, reproducible and robust since all the samples analyzed had coefficient of variation of less than 5% and no statistically significant difference between theoretical and practical concentrations was detected. Thus, a rapid, simple, low cost and sensitive spectrophotometric method was developed and validated for determining the content of inclusion complex and liposomes containing LPSF/AC04.

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