Czasopisma Uniwersytetu Przyrodniczy w Lublinie
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Extraction and analysis of ruscogenins from butcher’s broom (Ruscus aculeatus L.) rhizomes using HPLC
Get PDFButcher’s broom (Ruscus aculeatus L.) is a plant with valuable chemical composition and many medical applications. The underground rhizomes of the plant contain steroidal saponins, compounds with proven therapeutic effects and used mostly in treating venous insufficiency. The research aimed to optimise the extraction of saponins from butcher’s broom rhizomes to obtain the highest possible content of active compounds in the dry extract. The extraction was carried out in five variants using pure water or a mixture of water and ethanol as solvents in different potions. Three samples of butcher’s broom rhizomes from Albania, Bulgaria, and Germany were examined for the presence of highest level of sapogenin active ingredient. Results show that Albanian sample has the highest percentage of ruscogenins, and hence Albanian butcher’s broom rhizomes were chosen for the extraction of active ingredient by alcoholic solution with different concentration. The sapogenin content in the extracts was determined by the pharmacopoeial method using high performance liquid chromatography (HPLC). A strong, positive correlation was found between ethanol concentration and the content of ruscogenins in the dry extract. The most efficient variant of the extraction turned out to be the use of 50% ethanol as a solvent, where 304 mg of ruscogenins were obtained from 50 g of the raw material.Butcher’s broom (Ruscus aculeatus L.) is a plant with valuable chemical composition and many medical applications. The underground rhizomes of the plant contain steroidal saponins, compounds with proven therapeutic effects and used mostly in treating venous insufficiency. The research aimed to optimise the extraction of saponins from butcher’s broom rhizomes to obtain the highest possible content of active compounds in the dry extract. The extraction was carried out in five variants using pure water or a mixture of water and ethanol as solvents in different potions. Three samples of butcher’s broom rhizomes from Albania, Bulgaria, and Germany were examined for the presence of highest level of sapogenin active ingredient. Results show that Albanian sample has the highest percentage of ruscogenins, and hence Albanian butcher’s broom rhizomes were chosen for the extraction of active ingredient by alcoholic solution with different concentration. The sapogenin content in the extracts was determined by the pharmacopoeial method using high performance liquid chromatography (HPLC). A strong, positive correlation was found between ethanol concentration and the content of ruscogenins in the dry extract. The most efficient variant of the extraction turned out to be the use of 50% ethanol as a solvent, where 304 mg of ruscogenins were obtained from 50 g of the raw material
Pediatric tracheotomy: Results of a single center study on 46 patients
No full textIn this study, we aimed to present our tracheotomy experiences in pediatric patients in our hospital. We reviewed the data by analyzing pediatric tracheotomy retrospectively in terms of indications, follow-up and complications. Forty-six pediatric patients who underwent tracheotomy between 2014 and 2021 were included. The indications were examined under five headings according to the diagnoses that led to the tracheotomy of the patients. These were prolonged intubation, upper airway obstruction, craniofacial anomalies, neuromuscular disorders, and postoperative-traumatic sequelae. Twenty-three (50%) of these patients were girls, and 23 (50%) were boys. The mean age of the patients was 53.8±62.9 months. The youngest patient was a 1-day-old newborn, while the oldest patient was 15 years old. Pediatric tracheotomy was performed in 14 patients for prolonged intubation, 12 patients for craniofacial anomalies, 7 patients for upper airway obstruction, 7 patients for postoperative-traumatic sequelae and 6 patients for neuromuscular disorders. Preoperative or postoperative complications were seen in 10 of the patients. The intubation time of the patients who underwent elective tracheotomy was calculated as 25.7±17.1 days. Of these patients, the shortest duration of intubation was 6 days, and the longest duration was 90 days. The smallest diameter of the tracheostomy cannula inserted in the patients was 2.5 mm, while the largest was 7 mm, and the mean was 4.5 mm. In the follow-ups, it was observed that only 6 of the patients were decannulated, 11 of them died, and the remaining 29 continued their lives with tracheostomy. As a result, although pediatric tracheotomy is rare, it is a life-saving surgical procedure for the appropriate indications and can be successfully performed with manageable complications, contrary to expectations, with the appropriate surgical technique and adequate postoperative care
Outcomes of open tibial shaft fractures treated by external fixation method
No full textTibia is vulnerable to open fractures due to its relative inadequacy of soft tissue coverage. The optimal treatment method of open tibial fractures is still controversial. External fixators are widely used as a definitive treatment method for open fractures. The aim of the current study was to evaluate the outcomes of external fixators applied for open tibial shaft fractures. All open tibial fractures treated with external fixators between December 1999 and October 2008 were reviewed retrospectively. 48 limbs of 47 patients were included in this study. Fractures were classified as Type I in 4 (8.3%), Type II in 18 (37.5%), and Type III in 26 (54.2%) according to Gustilo-Anderson classification. The mean follow-up period was 58.3 months. 28 patients (29 limbs) underwent unilateral external fixation, and 19 patients received Ilizarov ring fixator. Fracture healing rates were 100% in Type I fractures, 88.9% in Type II fractures, 81.8% in Type IIIA fractures, 28.6% in Type IIIB fractures, and 62% in Type IIIC fractures. The mean time for removal of the external fixator was 24.06±12.44 weeks. The mean time to fracture union was 27.27±13.19 weeks. According to Karlstrom and Olerud criteria, the mean functional score was 31.04±3.77. Functional results were excellent in 6 limbs (12.5 %), good in 16 limbs (33.3 %), acceptable in 8 limbs (16.7%), moderate in 10 limbs (20.8%), and poor in 8 limbs (16.7%). Deep tissue infection developed in 5 limbs (10.4%). Osteomyelitis developed in 4 limbs (8.3%). The findings of our study suggest that satisfactory results can be obtained by using external fixators for the treatment of open tibial shaft fractures
The Effects of Fear of COVID-19 on Future Expectations in Nursing Students in Turkey
No full textThis study aims to determine the effects of fear of COVID-19 on future expectations among nursing students. The research is a correlational descriptive study. This study was conducted with 310 nursing students of a state university. The COVID-19 fear and future expectation mean scores of the participants were found, respectively, as 17.16 +/- 5.36 and 48.09 +/- 8.77. The COVID-19 fear levels of the participants significantly varied based on their gender, whereas their future expectation levels significantly varied based on their place of residence, status of willingly choosing their department and status of having someone in their surroundings and family who had COVID-19 (p 0.05). In this study, it was determined that the COVID-19 fear and future expectation levels of the nursing students were moderate. It was found that fear of COVID-19 did not significantly affect future expectations
Power flow analysis of AC/DC hybrid energy systems in smart grids
No full textElektrik enerjisinin üretim aşamasından başlayarak iletim, dağıtım ve tüketim aşamasına kadar tüm aşamalarında verimli, güvenli, çevre dostu bir enerji yönetimi oluşturulması akıllı şebeke kavramını ortaya çıkarmıştır. AC/DC hibrit enerji sistemleri iki veya daha fazla enerji üretim yöntemini kullanan sistemlerdir. Güç akış analizi ise elektrik enerji sistemlerinin analiz ve tasarımının temelini oluşturur. Güç akış analizinde amaç, bütün tüketim tesislerine yeterli miktarda, güvenilir, kaliteli, ekonomik ve kesintisiz enerji sağlamaktır. Bu çalışmada, değişken yenilenebilir dağıtık kaynaklar ve değişken yükler kullanılarak 13 baralı bir AC sisteminde 24 saatlik güç akış analizi yapılmıştır. Analizler soucunda baraların gerilim, aktif, reaktif ve kompleks güç grafikleri elde edilmiştir. Çalışmanın devamında, literatürde bulunan, gerilim kaynaklı dönüştürücüler (VSC) içeren hibrit 13 baralı AC/DC test sistemi Matlab platformunda hazırlanmış ve bu sistemin güç akışı analizi yapılmıştır. Elde edilen sonuçları literatürde olan sonuçlar ile karşılaştırılmıştır. Böylece önerilen hibrit 13 baralı AC/DC test sistemi güç akış algoritmasının doğruluğu kanıtlanmıştır. Daha sonra 13 baralı AC/DC test sistemi ve 13 baralı AC sistemi hat kayıplar yönünden karşılaştırılmıştır. Son olarak, IEEE 33 bara RDS (Radyal Dağıtım Sistemi) test sistemi kullanılarak yeni bir hibrit AC/DC sistemi hazırlanmıştır. Önerilen bu yeni sistem için Newton-Raphson ve Gauss-Seidel iterasyon metodları kullanılarak sistemin güç akışı analizi yapılmıştır. Analizler neticesinde elde edilen sonuçlar karşılaştırılarak değerlendirmeler yapılmıştır.Creating an efficient, safe, environmentally friendly energy management at all stages of electrical energy, starting from the generation stage to the transmission, distribution and consumption stages, has revealed the concept of smart grid. AC/DC hybrid energy is that type of systems that use two or more energy generation methods. Power flow analysis constitutes the basis of the analysis and design of electrical energy systems. The power flow analysis aims to provide sufficient, reliable, high-quality, cost-effective and uninterrupted power to all consumption facilities. In the present study, a 24-hour power flow analysis was performed in a 13 bus AC system by using variable renewable distributed sources and variable loads. As a result of the analysis, voltage, active, reactive and complex power graphs of the buses were obtained. Later, the hybrid 13 bus AC/DC test system with voltage source converters (VSC) in the literature was designed on the Matlab platform and the power flow analysis of this system was made. The results in this present study were compared with other results in the literature. Thus, the accuracy of the proposed hybrid 13 bus AC/DC test system power flow algorithm has been proved. Then, 13 bus AC/DC test system and 13 bus AC system were compared in terms of line losses. Finally, a new hybrid AC/DC system was designed using the IEEE 33 bus RDS (Radial Distribution Systems) test system. For this proposed new system, power flow analysis was performed using Newton-Raphson and Gauss-Seidel iteration methods. The results were compared and interpreted
Produção de prolina e protease com diferentes resíduos orgânicos em bactérias (Produção de prolina e protease com resíduos orgânicos)
No full textIn this study, we investigated the proline and protease production of different bacteria in several organic waste materials. Our aim was to produce proline and protease economically in waste that is abundantly available while reducing its environmental impact. 5 ml of different organic waste materials (OWW: Olive waste water; N.B: Nutrient Broth; EW: Eggshell; PBS: PBS buffer; PLW: Peach leaf wastes; TCW: Turkish coffee wastes; TWW: Tea waste water; WCW: Waste cheese whey; WFO: Waste frying oil) were placed in 10 ml grow tubes, inoculated and incubated for 24 h. Phosphate-buffered saline and 10% solutions of different organic wastes were added. These cultures were subsequently incubated at 37°C for 24 h. Cells were harvested at 24 h for L-proline assay. 1 ml of culture was transferred by pipette into an Eppendorf tube and centrifuged at 14,000 rpm for 20 min at room temperature. Cellular debris was removed by centrifuge and the supernatant was used for proline activity assays. Protease activity was determined using a modified method with casein as the substrate. We found that proline and protease can easily be produced economically using Turkish coffee wastes (TCW), Waste cheese whey (WCW) and Olive waste water (OWW) organic waste. We believe that this study will result in similar research leading to the economical use of these waste materials thus reducing their impact on the environment. © 2022, Instituto Internacional de Ecologia. All rights reserved
Eco-friendly chitosan/?-carrageenan membranes reinforced with activated bentonite for adsorption of methylene blue
No full textIn this work, the chitosan/kappa-carrageenan/acid-activated bentonite composite membranes were prepared through blending method and used to adsorb methylene blue dye. The prepared composite membranes were characterized with several spectroscopic and microscopic techniques. The results revealed that the bentonite was homogeneously distributed in the membrane matrix, which means extensive porous structure was formed on the surface. The effects of initial concentration of methylene blue, adsorbent dosage, pH value, contact time, ionic strength, and temperature on methylene blue removal percentage the prepared membrane was investigated in detail. Adsorption kinetics and equilibrium adsorption isotherm fitted pseudo-second-order kinetic model and Freundlich isotherm model well, respectively. The thermodynamics analysis suggested that the adsorption process of methylene blue onto the chitosan/kappa-carrageenan/acid-activated bentonite composite membrane was spontaneous and endothermic. The highest removal rate (98%) was achieved under the following conditions: adsorbent dose, 0.05 g; solution pH, 4; temperature, 50 degrees C; and time, 200 min. The maximum adsorption capacity for methylene blue was 18.80 mg/g at 50 degrees C. Moreover, the prepared composite membrane demonstrated the high reusability and adsorption rate (similar to 77%) without significant loss after sixth adsorption-desorption cycles. Considering of the above results, the prepared composite membrane can be a promising adsorbent candidate having low cost and high recyclability to remove methylene blue
No association of Gaucher disease with COVID-19-related outcomes: a nationwide cohort study
No full textBackground It is well documented that patients with chronic metabolic diseases, such as diabetes and obesity, are adversely affected by the COVID-19 pandemic. However, when the subject is rare metabolic diseases, there are not enough data in the literature. Aim To investigate the course of COVID-19 among patients with Gaucher disease (GD), the most common lysosomal storage disease. Methods Based on the National Health System data, a retrospective cohort of patients with confirmed (polymerase chain reactionpositive) COVID-19 infection (n = 149 618) was investigated. The adverse outcomes between patients with GD (n = 39) and those without GD (n = 149 579) were compared with crude and propensity score-matched (PSM) groups. The outcomes were hospitalisation, the composite of intensive care unit (ICU) admission and/or mechanical ventilation and mortality. Results The patients with GD were significantly older and had a higher frequency of hypertension (HT), Type 2 diabetes mellitus (T2DM), dyslipidaemia, asthma or chronic obstructive pulmonary disease, chronic kidney disease, coronary artery disease, heart failure and cancer. Although hospitalisation rates in Gaucher patients were found to be higher in crude analyses, the PSM models (model 1, age and gender matched; model 2, matched for age, gender, HT, T2DM and cancer) revealed no difference for the outcomes between patients with GD and the general population. According to multivariate regression analyses, having a diagnosis of GD was not a significant predictor for hospitalisation (P = 0.241), ICU admission/mechanical ventilation (P = 0.403) or mortality (P = 0.231). Conclusion According to our national data, SARS-CoV-2 infection in patients with GD does not have a more severe course than the normal population
Ram makinelerindeki hava akışının Hesaplamalı Akışkanlar Dinamiği ile modellenmesi
No full textBu çalışmada, bir tekstil fabrikasında aktif olarak kullanılan bir ram makinesindeki hava akışı Hesaplamalı Akışkanlar Dinamiği (HAD) yöntemi ile modellenmiştir. Sayısal akış simülasyonları ANSYS Fluent paket programında gerçekleştirilmiştir. Akış rejimi daimi ve türbülanslı akıştır. Reynolds Ortalamalı Navier –Stokes (RANS) denklemleri Fluent’te çözdürülmüş, analizlerde Standart k-? türbülans modeli seçilmiştir. Akış alanına ait hız verileri görsellerle sunulmuş ve akış verimliliğini etkileyen parametreler karşılaştırılmıştır. Analizler farklı düze geometrileri için gerçekleştirilmiştir. Geometri değişiklikleri düze açıklık oranı (B) ve düze açısı (?) değiştirilerek sağlanmıştır. Mevcut düze geometrisi ile farklı geometrilerin akış alanına ait hız değişkenleri üzerinden karşılaştırma yapılmıştır. Düze açıklık oranının %20-30 civarında ve düze açısının 0o (ki bu düzenin yatay konumda olduğu anlamına gelir) olmasının ram makinesinde daha verimli bir akış sağladığı sonucuna varılmıştır
Application of Numerical and Experimental Modeling to Improve the Efficiency of Parshall Flumes: A Review of the State-of-the-Art
No full textOne of the primary steps in managing the flow in an open channel is determining its properties. Empirical equations are developed to provide further information regarding the flow in open channels. Obtaining such experimental equations is expensive and time consuming; therefore, alternative solutions have been sought. Over the last century, the Parshall flume, a static measuring device with no moving parts, has played a significant role in measuring the flow in open channels. Many researchers have focused their interest on studying the application of Parshall flumes in various fields like irrigation and wastewater management. Although various scholars used experimental results to enhance the rating equation of the Parshall flume, others used an alternative source of data to recalibrate the height-discharge relation equation using numerical simulation. Computational Fluid Dynamic (CFD) software is becoming popular nowadays as computing hardware has advanced significantly within the last few decades, making it possible to go beyond the limited resolution that was experienced in the past. Multiple CFD models, depending on their availability, either open-source or commercially licensed, have been used to perform numerical simulations on different configurations of flumes, especially Parshall flumes, to produce water level results. Regarding various CFD tools that have been used, i.e., FLOW-3D, Ansys Fluent, or OpenFOAM, after precise calibration with experimental data, it has been determined that the output is reliable and can be implemented to the actual scenarios. The benefit of using this technique to produce results is the ability of the CFD approach to adjust the initial conditions, like flow velocity or structural geometry, where necessary. With respect to channel size and the condition of the site where the flume is located, the choices are narrowed to the specific Parshall flume suitable to the situation. It is not always possible to select the standard Parshall flume; therefore, engineers provide some modification to the closest flume size and provide a new rating curve to produce accurate flowrates. This review has been performed on the works of a number of scholars who targeted the application of numerical simulation and physical experimental data in Parshall flumes to either enhance the existing rating equation or propose further modification to the structure's geometry.Discovery (NSERC) [210282]FundingThis research was supported by funding provided by Discovery (NSERC) Grants to Prof. Majid Mohammadian and Prof. Ioan Nistor (210282)