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2022 ◽  
Vol 10 (1) ◽  
pp. 8-14
Author(s):  
N. Eliza ◽  
R. Dewanti-Hariyadi ◽  
S. Nurjanah

Bacillus cereus is known to have the ability to adhere and form biofilms on the surface of stainless steel that causes problems in the food industries. Bacterial biofilms generally can increase resistance to sanitizer treatment. This study aimed to evaluate the ability of peracetic acid-based commercial sanitizer to inactivate B. cereus biofilm on stainless steel (SS) surfaces. Biofilm of B. cereus ATCC 10876 was developed on SS surfaces and treated with 7 commercial peracetic acid-based sanitizers at their recommended dosages. Two sanitizers, i.e. B (peracetic acid and QAC) and F (peracetic acid and acidified water) showing the ability to inactivate B. cereus on solid media at concentration of 200, 400, and 800 ppm were further tested on biofilms with contact times of 1, 3, and 5 minutes. The 48 hours biofilms B. cereus contained 2.78-3.78 CFU/cm2. Both sanitizers B and F had significant effects in inactivating B. cereus biofilm. In general, sanitizer B could reduce more biofilm bacteria at any contact time than sanitizer F. Use of 200 ppm of sanitizer B or F 5 minutes could inactivate 3.04 log CFU/cm2 and 2.68 log CFU/cm2 biofilm, respectively. Exposure of B. cereus biofilm to peracetic acid-based sanitizer resulted in the damage of the extracellular matrix of the biofilms. This study showed that commercial sanitizers containing peracetic acid and quaternary ammonium compounds were effective in inactivating B. cereus biofilms.


Foods ◽  
2022 ◽  
Vol 11 (2) ◽  
pp. 164
Author(s):  
Francesco Corrias ◽  
Efisio Scano ◽  
Giorgia Sarais ◽  
Alberto Angioni

Swordfish is the most widespread billfish in the aquatic environment. The industrial processing of swordfish fillets involves salting, drying, and smoking steps. Salting techniques, dry or wet, are the most common method of fish preservation. This work evaluated salt diffusion in swordfish fillets after traditional dry salting and wet industrial injection salting methods. The data obtained from the dry salting studies highlighted that the salt diffusion process in swordfish meat was an unfavorable process depending on the contact time with the salt/meat. Moreover, irregularly shaped fillets negatively affected the salt migration in the different areas, leading to inhomogeneous and possibly unsafe final products. On the contrary, wet injection salting was suitable for processing swordfish fillets. As a result, the final products had a homogeneous salt concentration, maintained the organoleptic characteristics and health benefits for a long period, and achieved a longer shelf-life. Furthermore, the water activity (aw) values detected for the different processed fillets confirmed the physicochemical features of the final products and allow the classification of safe products. Moreover, injection salting is a quick process compatible with industrial production times.


Author(s):  
INSAN SUNAN KURNIAWANSYAH ◽  
IYAN SOPYAN ◽  
GENI REFSI

In situ ophthalmic gel is a type of eye drug preparation that has a higher bioavailability value and has a longer contact time with maximum therapeutic effect and with minimal side effects compared to conventional eye preparations. The preparation of ophthalmic in situ gel is required characterization to make sure that the prepared preparations meet the standards and are safe when used. This journal review aims to look at the methods used in characterizing physical properties in in situ ophthalmic gel formulations with different active substances such as rheology studies, organoleptic tests, pH, clarity, and gelling capacity. In order to get the best formulation of in situ ophthalmic gel preparations so as to provide maximum therapeutic effect.


2022 ◽  
Vol 12 (1) ◽  
pp. 506
Author(s):  
Marta Izquierdo-Renau ◽  
Roberto Sanchis-Sanchis ◽  
Jose I. Priego-Quesada ◽  
Alberto Encarnación-Martínez ◽  
Ana Queralt ◽  
...  

The use of minimalist shoes (MS) in running involves changes in running mechanics compared to conventional shoes (CS), but there is still little research analysing the effects of this footwear on plantar pressure, which could help to understand some risk injury factors. Moreover, there are no studies examining the effects of a prolonged running and foot strike patterns on baropodometric variables in MS. Therefore, the aim of this study was to analyse the changes produced using MS on plantar pressure during a prolonged running, as well as its interaction with the time and foot strike pattern. Twenty-one experienced minimalist runners (age 38 ± 10 years, MS running experience 2 ± 1 years) ran with MS and CS for 30 min at 80% of their maximal aerobic speed, and mean pressure, peak pressure, contact time, centre of pressure velocity, relative force and contact area were analysed using a pressure platform. Foot strike pattern and time were also considered as factors. The multivariable linear regression mixed models showed that the use of MS induced, at the end of a prolonged running, higher peak pressure (p = 0.008), lower contact time (p = 0.004) and lower contact area (p < 0.001) than using CS. Also, runners with forefoot strike pattern using MS, compared to midfoot and rearfoot patterns, showed higher mean and peak pressure (p < 0.001) and lower contact time and area (p < 0.05). These results should be considered when planning training for runners using MS, as higher peak pressure values when using this type of footwear could be a risk factor for the development of some foot injuries.


Author(s):  
Hussein I. Abdel-Shafy ◽  
Rehan M. M. Morsy ◽  
Mahmoud A. I. Hewehy ◽  
Taha M. A. Razek ◽  
Maamoun M. A. Hamid

Abstract A real industrial electroplating rinsing wastewater was collected and subjected the physical and chemical examination. The study showed that it can be categorized as high strength wastewater, at pH- 2, COD 1430 mg/l, and high level of metals above permissible limits namely: 150, 30, 25, and 2.9 for Ni, Cu, Zn, and Fe mg/l respectively. Therefore, metals must be adequately removed before discharging to avoid any hazardous impact on the environment. Similar synthetic wastewater was prepared to study effect of chemical coagulation for the precipitation of metals. The optimum removal rate was achieved by using a combination of lime and ferric chloride at 100 and 30 mg/l respectively. The chemically treated electroplating wastewater was subjected to an electrocoagulation study. A comparison between iron and stainless-steel electrodes for the removal of metals was investigated. Furthermore, the effect of different electric voltage, and the contact time on metals removal efficiency were also examined. It was found that the optimum removal capacity was achieved when stainless steel electrode was employed in the presence of ferric chloride as coagulant, at 10 volts, 30 min. contact time, and pH 9 for synthetic solution. In a batch treatment system, the real industrial wastewater was treated at the predetermined optimum operating conditions; the removal of metals was 92.1%, 87.8% and 82.9% for Ni. Zn, and Cu respectively. By employing a continuous flow reactor for the treatment of the same real wastewater and under the same operating conditions; metals removal rate increased to 98.9%, 97.4% and 96.6% for Ni. Zn, and Cu respectively. The level of metals in the final treated wastewater copes with Egyptian Environmental Regulation. The overall results confirmed that the electro-coagulation (EC) technology offers an effective alternative process in combination with the conventional chemical coagulation process for reaching high removal performance of toxic metals from the electroplating wastewater. The advantage of EC technique is achieving high treatment efficiency instead of expensive chemical reagents, high construction cost and/or other conventional processes. In addition, the final treated water can be reused for rinsing process in electroplating industry and/or discharging without any environmental hazard effect. It is also recommended to employ solar energy instead of electricity to reduce cost of operation.


Author(s):  
Johan Cassirame ◽  
Hervé Sanchez ◽  
Sébastien Homo ◽  
Julien Frère

In pole vaulting, take-off speed is considered as a major determinant of performance. Pole carriage could affect the speed acquired during the approach and at the take-off. This study investigated different types of runs performed randomly by young male and female expert athletes: maximal sprint, maximal pole carriage run, maximal run-up with simulated pole plant and competition situation. Speed profile was determined with a radar gun and spatiotemporal parameters were recorded for the last 20 m of the approach with the Optojump Next system. For both genders, mechanical variables were compared using two-way ANOVAs with repeated measurements. Pole carriage represents the main cause of speed decrease for both men (−5.8%) and women (−6.2%). A step rate decrease during pole carriage was pointed out with an increase of contact time for both men and women. Significant speed decrease was observed for women at the take-off compared to pole plant simulation (−4.3%), while not for men. Those results provide a new insight for pole vault training allowing to update training process with specific exercises leading to reduce speed loss at take-off.


2022 ◽  
Vol 10 (1) ◽  
pp. 232596712110638
Author(s):  
N.M. Nuala Crotty ◽  
Katherine A.J. Daniels ◽  
Ciaran McFadden ◽  
Niall Cafferkey ◽  
Enda King

Background: Deficits in knee strength after anterior cruciate ligament reconstruction (ACLR) surgery are common. Deficits in the single-leg drop jump (SLDJ), a test of plyometric ability, are also found. Purpose: To examine the relationship between isokinetic knee strength, SLDJ performance, and self-reported knee function 9 months after ACLR. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Knee isokinetic peak torque, SLDJ jump height, contact time, and reactive strength index (RSI), as well as International Knee Documentation Committee (IKDC) scores were assessed in 116 male, field-sport athletes at 9.2 months after ACLR. SLDJ testing took place in a 3-dimensional biomechanics laboratory. Linear regression models were used to analyze the relationship between the variables. Results: A significant relationship was found between ACLR-limb isokinetic knee extensor strength and SLDJ jump height ( P < .001, r 2 = 0.29) and RSI ( P < .001, r 2 = 0.33), and between ACLR-limb isokinetic knee flexor strength and SLDJ jump height ( P < .001, r 2 = 0.12) and RSI ( P < .001, r 2 = 0.15). A significant positive relationship was also found between knee extensor asymmetry and SLDJ jump height asymmetry ( P < .001, r 2 = 0.27) and SLDJ reactive strength asymmetry ( P < .001, r 2 = 0.18). Combined ACLR-limb jump height and contact time best predicted IKDC scores ( P < .001, r 2 = 0.12). Conclusion: Isokinetic knee extension strength explained approximately 30% of SLDJ performance, with a much weaker relationship between knee flexion strength and SLDJ performance. Isokinetic strength and SLDJ performance were weak predictors of variation in IKDC scores.


2021 ◽  
Vol 17 (6) ◽  
pp. 768-775
Author(s):  
Fadina Amran ◽  
Nur Fatiah Zainuddin ◽  
Muhammad Abbas Ahmad Zaini

The present work was aimed at evaluating the performance of two-stage adsorber for methylene blue removal by coconut shell activated carbon in minimizing the adsorbent mass and contact time. The Langmuir constants were used to evaluate the optimum mass, while the pseudo-second-order constants for contact time. Results show that the adsorbent mass can only be minimized by 0.01 % due to the high adsorbent affinity towards methylene blue, while the contact time has been optimized to 12.2 min at the studied conditions. The effect of adsorbent affinity in two-stage adsorber was analyzed to shed some light about its importance in the design of two-stage adsorber. The performance evaluation was also discussed to bring insight into wastewater treatment applications.


Author(s):  
Lukumon Salami ◽  
Lukman Bakare

Process optimization plays a very important role in the process industries as it helps to miximise desire output by minimizing the cost of process variables. The aim of this work is to carry out response surface central composite design optimization of Soluos dumpsite leachate treatment using agricultural biowaste. Leachate collected from Soluos dumpsite in Lagos was treated using adsorbent prepared from Muas sapientum peels by studying the effects of adsorbent dosage and contact time on the percentage removal of total dissolved solids (TDS) with the aid of design expert software version 10.0.3. The developed second order regression model was adopted in comparison with the linear and two factor interaction ( ) model based on its coefficient of determination (R2) value and its adequacy by analysis of variance (ANOVA). 80.34 percentage removal of TDS was achieved under experimental process at contact time of 120 mins and dosage of 1 g/100mL while 81.134 percentage removal of TDS was obtained under simulation process at contact time of 63.469 mins and dosage of 0.994 g/100 mL. the values obtained under simulation condition were adopted as the optimum conditions. The developed second order regression model predicted the experimental data up to 98.10 percent confidence level hence it is a true representation of the treatment process and can be used to navigate the design space and optimization process of treatment of Soluos dumpsite leachate.


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