2020 ◽  
Vol 16 (5) ◽  
pp. 793-804
Author(s):  
Naimeh Mahheidari ◽  
Jamal Rashidiani ◽  
Hamid Kooshki ◽  
Khadijeh Eskandari

Background: Today, nanoparticles hold great promise in biomedical researches and applications including bacteria detection. The rapid and sensitive outcomes of bacteria detection strategies using nanoparticle conjugates become determinative, especially in bacterial outbreaks. In the current research, we focused on detecting V. cholera bacteria and its toxin using a thiocyanate/Au nanoparticle. Thiocyanate adsorbed strongly on the surface of gold nanoparticles and changed the surface by enhancing surface plasmon resonance of gold nanoparticles. Objective: This method is tried to introduce a simple and fast procedure to assay vibrio cholera. So, it is observed by the naked eyes as well. Methods: We used two antibodies (Ab) for V. cholera detection: a) a primary antibody conjugated to magnetic nanoparticles (MNPs) for trapping V. cholera bacterial cells, and b) a secondary Abconjugated thiocyanate-GNPs as a colorimetric detector. Then, an immuno-magnetic separation system connected to a colorimetric assay was designed based on the GNPs. The results were measured by ultraviolet-visible (UV-Vis) spectroscopy. Results: The results showed that gold nanoparticles are an appropriate optical assay for detecting biological samples in a minimum concentration and also it can be easily seen by the naked eyes. The linear range of this biosensor is 3.2×104 to 28×104 cells per ml. Conclusion: In this research, a colorimetric immune assay based on gold nanoparticles was designed to improve the sensitivity of V. cholera detection. Also, this method can be used for the detection of other biological agents.


Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3537
Author(s):  
Christian Friedrich ◽  
Steffen Ihlenfeldt

Integrated single-axis force sensors allow an accurate and cost-efficient force measurement in 6 degrees of freedom for hexapod structures and kinematics. Depending on the sensor placement, the measurement is affected by internal forces that need to be compensated for by a measurement model. Since the parameters of the model can change during machine usage, a fast and easy calibration procedure is requested. This work studies parameter identification procedures for force measurement models on the example of a rigid hexapod-based end-effector. First, measurement and identification models are presented and parameter sensitivities are analysed. Next, two excitation strategies are applied and discussed: identification from quasi-static poses and identification from accelerated continuous trajectories. Both poses and trajectories are optimized by different criteria and evaluated in comparison. Finally, the procedures are validated by experimental studies with reference payloads. In conclusion, both strategies allow accurate parameter identification within a fast procedure in an operational machine state.


2015 ◽  
Vol 21 (4) ◽  
pp. 287-291 ◽  
Author(s):  
Valéria Cristina de Faria ◽  
João Carlos Bouzas Marins ◽  
Gustavo Antônio de Oliveira ◽  
Samuel de Souza Sales ◽  
Fernando Fonseca dos Reis ◽  
...  

INTRODUCTION: To ensure performance and health, the type of food and the time of pre-exercise ingestion should be considered by practitioners of morning physical activity. Objective: This study assessed the metabolic response after pre-exercise meals with different glycemic indexes (GI) and in the fasting state adopting different types of hydration.METHODS: Twelve men performed four experimental tests; two with pre-exercise meals of high GI (HGI) and low GI (LGI), and two were performed in the fasting state with hydration: water (H2O) and carbohydrate drink (CHO). Each test consisted of a pre-exercise rest period of 30 minutes followed by 60 minutes of cycle ergometer with continuous load equivalent to 60% of the extrapolated maximal oxygen consumption (VO2MaxExt). During the exercise, participants were hydrated every 15 minutes with 3mL per kg body weight. During each experimental test, venous blood samples were obtained for fasting and at 15-minute intervals during rest, and every 20 minutes during exercise. The gas analysis was carried out in periods of 5 minutes every 20 minutes of exercise.RESULTS: There was no difference in substrate oxidation. After 20 minutes of exercise, pre-exercise food intake procedures showed similar behavior, having only reduced blood glucose levels compared to fasting procedures (p<0.01). There was maintenance of blood glucose at stable and higher levels during exercise in relation to the other tests in the fast procedure with CHO.CONCLUSION: The data suggest that despite the similar metabolic behavior between LGI and HGI meals, the adoption of a LGI meal before the morning exercise seems to be a more suitable feeding practice due to higher tendency of rebound hypoglycemia after HGI meal and when morning exercise is performed on fasting, hydration with CHO seems to minimize the hypoglycemic risk arising from that state.


2003 ◽  
Vol 11 (1) ◽  
pp. 33-35 ◽  
Author(s):  
JP Brutus ◽  
A Nikolis ◽  
Y Baeten ◽  
N Chahidi ◽  
L Kinnen ◽  
...  

Background Regional anesthesia of a single finger is commonly achieved by the traditional ring block, which requires at least two painful injections in the digit. Single injection digital block techniques have been described to avoid this problem. Among these, the subcutaneous technique described by Harbison appears to be safe and to allow most procedures to be carried out with good tolerance. Objectives A prospective study was designed to evaluate the results of the subcutaneous technique in terms of patient tolerance, distribution of anesthesia and efficiency. Methods All blocks were performed by a single investigator. A visual analog scale was used to evaluate pain associated with the injection. Prick testing was used to evaluate the quality of anesthesia at the volar and dorsal aspects of the phalanxes. Tolerance to the surgical procedure and the need for additional injections were also recorded. Results This technique allowed surgery to be performed without complementary injection most of the time and was very well tolerated. The dorsum of the proximal phalanx, however, was unpredictably included in the anesthetized territory. Conclusion The subcutaneous single injection digital block is safe, efficient and easy to perform. It allows the treatment of all conditions on the volar aspect of the finger and on the dorsal aspect of the distal and middle phalanxes. For surgery on the dorsal aspect of the proximal phalanx, a combined single injection technique or a supplementary dorsal block should be used.


RSBO ◽  
2018 ◽  
Vol 1 (3) ◽  
pp. 186
Author(s):  
Katiane Vieira Menezes Leite ◽  
Patrícia Oliveira de Souza ◽  
Jussania Fonseca da Paz ◽  
Ana Beatriz Franco Fernandes ◽  
Leonardo Fernandes da Cunha ◽  
...  

Introduction: The gingival melanin hyperpigmentation (GMH) is resulted from an abnormal deposition of melanin, but it is not a pathology. However, GMH is an esthetic problem for some people. Some alternatives of treatment for this situation exist. The epithelial abrasion has been an interesting alternative because it has a satisfactory esthetic outcome, is a fast procedure, of easy execution, and low cost. Recently, tips adapted in ultrasound (CVDentus) can bean alternative approach. Objective: To report a clinical case of GMH treated by the technique of the epithelial abrasion with association of instrument adapted in ultrasound. Case report: Patient aged 28 years, melanoderm, sought treatment due to esthetic dissatisfaction because of intense dark color in the maxillary gingiva. The GMH removal was proposed through the technique of the epithelialabrasion CVD bur. Conclusion: The technique of epithelial abrasion using CVD bur was effective in removing GMH at one-year follow-up showing to be easy and safe technique.


2007 ◽  
Vol 344 ◽  
pp. 127-134 ◽  
Author(s):  
Fabrizio Quadrini ◽  
Loredana Santo ◽  
Erica Anna Squeo

An easy and innovative technique for metal sheet characterization is described. A double indentation is performed on sheets by means of two co-axial small diameter flat indenters made of WC. A very small indentation is left on the sheet, so as to consider this technique a non destructive one, particularly suitable for on-line application. The proposed method was tested on sheets of aluminum alloy (6082 T6) with several thicknesses (nominally 0.6, 0.8, 1 and 1.5 mm). Double indentations were performed changing indenter diameter (1 and 2 mm) and testing rate (from 0.05 to 1 mm/min). In order to make a comparison with indentation tests, flat specimens were cut from the same sheets and standard tensile tests were performed. A very good correlation was found between indentation and tensile test results, showing the effectiveness of the proposed method. A suitable data normalization is necessary to correctly compare indentation and tensile data. The best results were obtained using the smaller diameter indenter. The testing rate seems to be not relevant in the experimented range, suggesting that a fast procedure can be defined on purpose for on-line application.


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