Optimization of the Ultrasound Operating Conditions for Extraction and Quantification of Fructooligosaccharides from Garlic (Allium sativum L.) via High-Performance Liquid Chromatography with Refractive Index Detector

Dietary interventions have captured the attention of nutritionists due to their health-promoting aspects, in addition to medications. In this connection, supplementation of nutraceuticals is considered as a rational approach to alleviating various metabolic disorders. Among novel strategies, prebiotic-supplemented foods are an encouraging trend in addressing the issue. In the present investigation, prebiotic fructooligosaccharides (FOS) were extracted from garlic (Allium sativum L.) powder using ultrasound-assisted extraction (UAE). The response surface methodology (RSM) was used to optimize the independent sonication variables, i.e., extraction temperature (ET, 80, 90, and 100 °C), amplitude level (AL, 70, 80, and 90%) and sonication time (ST, 10, 15 and 20 min). The maximum FOS yield (6.23 ± 0.52%) was obtained at sonication conditions of ET (80 °C), AL (80%) and ST (10 min), while the minimum yield of FOS was obtained at high operating temperatures and time. The optimized FOS yield (7.19%) was obtained at ET (80 °C), AL (73%) and ST (15 min) after model validation. The influence of sonication parameters, i.e., ET, AL and ST, on FOS yield was evaluated by varying their coded levels from −1 to +1, respectively, for each independent variable. High-performance liquid chromatography with refractive index detector (HPLC-RID) detection and quantification indicated that sucrose was present in high amounts (2.06 ± 0.10 g/100 g) followed by fructose and glucose. Total FOS fractions which included nystose present in maximum concentration (526 ± 14.7 mg/100 g), followed by 1-kestose (428 ± 19.5 mg/100 g) and fructosylnystoses (195 ± 6.89 mg/100 g). Conclusively, garlic is a good source of potential prebiotics FOS and they can be extracted using optimized sonication parameters using ultrasound-assisted techniques with maximum yield percentage

Effect of fat contents of buttermilk on fatty acid composition, lipolysis, vitamins and sensory properties of cheddar-type cheese

Cheddar-type cheese produced from buttermilk had softer texture than standard cheddar cheese due to lower fat content of buttermilk. Fat is extremely important for the functional characteristics and optimum textural attributes of cheese. The effect of different fat contents of buttermilk on chemical characteristics of cheddar-type cheese is not previously investigated. This investigation was conducted to know the effect of different fat contents of buttermilk on fatty acids composition, organic acids, vitamins, lipolysis and sensory characteristics of cheddar-type cheese. Cheddar-type cheese was produced from buttermilk having 1, 1.75, 2.50 and 3.25% fat contents (control, T1, T2 and T3). Fat content of control, T1, T2 and T3 were 9.81, 16.34, 25.17 and 31.19%. Fatty acids profile was determined on GC–MS, organic acids and vitamin A and E were determined on HPLC. Free fatty acids, peroxide value and cholesterol were determined. Cheddar-style cheese produced from buttermilk (1% fat) showed that it had softer texture and lacking typical cheese flavor. Gas chromatography–mass spectrometry (GC–MS) analysis showed that long-chain unsaturated fatty acids in control, T1, T2 and T3 samples were 45.88, 45.78, 45.90 and 46.19 mg/100 g. High Performance Liquid Chromatography (HPLC) analysis showed that lactic acid, propionic acid, citric acid and acetic acid gradually and steadily increased during the storage interval of 90 days. At the age of 90 days, lactic acid in control, T1, T2 and T3 was 4,789, 5,487, 6,571 and 8,049 ppm, respectively. At the end of ripening duration of 90 days, free fatty acids in control, T1, T2 and T3 were 0.29, 0.31, 0.35 and 0.42% with no difference in peroxide value. Stability of vitamin A after 90 days storage control, T1, T2 and T3 was 87.0, 80.0, 94.0 and 91.0%. Flavor score of cheddar-type cheese produced from butter milk having 1.0, 2.5 and 3.25% fat content was 81, 89 and 91% of total score (9). Hence, it is concluded that cheddar-type cheese can be produced from buttermilk having 2.5 and 3.25% fat contents with acceptable sensory attributes. Application of buttermilk for the production of other cheese varieties should be studied

Effect of fat contents of buttermilk on fatty acid composition, lipolysis, vitamins and sensory properties of cheddar-type cheese

Cheddar-type cheese produced from buttermilk had softer texture than standard cheddar cheese due to lower fat content of buttermilk. Fat is extremely important for the functional characteristics and optimum textural attributes of cheese. The effect of different fat contents of buttermilk on chemical characteristics of cheddar-type cheese is not previously investigated. This investigation was conducted to know the effect of different fat contents of buttermilk on fatty acids composition, organic acids, vitamins, lipolysis and sensory characteristics of cheddar-type cheese. Cheddar-type cheese was produced from buttermilk having 1, 1.75, 2.50 and 3.25% fat contents (control, T1, T2 and T3). Fat content of control, T1, T2 and T3 were 9.81, 16.34, 25.17 and 31.19%. Fatty acids profile was determined on GC–MS, organic acids and vitamin A and E were determined on HPLC. Free fatty acids, peroxide value and cholesterol were determined. Cheddar-style cheese produced from buttermilk (1% fat) showed that it had softer texture and lacking typical cheese flavor. Gas chromatography–mass spectrometry (GC–MS) analysis showed that long-chain unsaturated fatty acids in control, T1, T2 and T3 samples were 45.88, 45.78, 45.90 and 46.19 mg/100 g. High Performance Liquid Chromatography (HPLC) analysis showed that lactic acid, propionic acid, citric acid and acetic acid gradually and steadily increased during the storage interval of 90 days. At the age of 90 days, lactic acid in control, T1, T2 and T3 was 4,789, 5,487, 6,571 and 8,049 ppm, respectively. At the end of ripening duration of 90 days, free fatty acids in control, T1, T2 and T3 were 0.29, 0.31, 0.35 and 0.42% with no difference in peroxide value. Stability of vitamin A after 90 days storage control, T1, T2 and T3 was 87.0, 80.0, 94.0 and 91.0%. Flavor score of cheddar-type cheese produced from butter milk having 1.0, 2.5 and 3.25% fat content was 81, 89 and 91% of total score (9). Hence, it is concluded that cheddar-type cheese can be produced from buttermilk having 2.5 and 3.25% fat contents with acceptable sensory attributes. Application of buttermilk for the production of other cheese varieties should be studied.info:eu-repo/semantics/publishedVersio

Physiological parameters for Prognosis in Abdominal Sepsis (PIPAS) Study : a WSES observational study

BackgroundTiming and adequacy of peritoneal source control are the most important pillars in the management of patients with acute peritonitis. Therefore, early prognostic evaluation of acute peritonitis is paramount to assess the severity and establish a prompt and appropriate treatment. The objectives of this study were to identify clinical and laboratory predictors for in-hospital mortality in patients with acute peritonitis and to develop a warning score system, based on easily recognizable and assessable variables, globally accepted.MethodsThis worldwide multicentre observational study included 153 surgical departments across 56 countries over a 4-month study period between February 1, 2018, and May 31, 2018.ResultsA total of 3137 patients were included, with 1815 (57.9%) men and 1322 (42.1%) women, with a median age of 47years (interquartile range [IQR] 28-66). The overall in-hospital mortality rate was 8.9%, with a median length of stay of 6days (IQR 4-10). Using multivariable logistic regression, independent variables associated with in-hospital mortality were identified: age > 80years, malignancy, severe cardiovascular disease, severe chronic kidney disease, respiratory rate >= 22 breaths/min, systolic blood pressure 4mmol/l. These variables were used to create the PIPAS Severity Score, a bedside early warning score for patients with acute peritonitis. The overall mortality was 2.9% for patients who had scores of 0-1, 22.7% for those who had scores of 2-3, 46.8% for those who had scores of 4-5, and 86.7% for those who have scores of 7-8.ConclusionsThe simple PIPAS Severity Score can be used on a global level and can help clinicians to identify patients at high risk for treatment failure and mortality.Peer reviewe

3D numerical modeling of boiling in a microchannel by arbitrary Lagrangian-Eulerian (ALE) method

The arbitrary Lagrangian-Eulerian method (ALE) is used to model the hydrodynamics and the heat transfer of an elongated vaporized bubble in a rnicrotube. The Navier-Stokes equations along with the energy equation are solved in ALE description as a single fluid with two subdomains and a moving mesh at the interface of the liquid and the vapor phases. The numerical framework is the commercial CFD code COMSOL multiphysics with the finite element method, which has been improved by external functions to the phase changing. In the simulations, the nucleated bubble comes in contact with superheated water and starts growing. The growth rate of the bubble in the proposed model and the thin liquid film between the elongated bubble and the channel wall are in a very good agreement with the analytical solution and the empirical correlation in the literature, respectively. The interactive effects of two elongated bubbles also are presented

Numerical simulation of flow boiling from an artificial cavity in a microchannel

Cahn Hilliard phase-field method is used to numerically simulate subcooled water boiling in which nucleation occurs from an artificial cavity on the inner surface of a microchannel. The boiling initiates from a cavity and the growth and departure of the nucleated bubbles from the cavity are simulated. The velocity, temperature and pressure distributions inside the microchannel have been analyzed. The bubble generation frequency increases by increasing inlet mass flux. For this case of study, the rising trend continues up to the mass flux of 64 kg/m(2) s. Further increase in the inlet mass flux does not accelerate the bubble formation. The radius and the shape of the generated bubble compared well with experimental data available in the literature

Heat transfer and pressure drop experiments on CMOS compatible microchannel heat sinks for monolithic chip cooling applications

Novel CMOS compatible microchannel heat sinks are designed, fabricated and tested for monolithic liquid cooling of integrated circuits. The proposed heat sink is fabricated by low temperature surface micromachining processes and requires no design change of the electronic circuitry underneath, hence, can be produced by adding a few more steps to the standard CMOS fabrication flow. The microchannel heat sinks were tested successfully under various heat flux and coolant flow rate conditions. The cooling tests have shown that the microchannel heat sinks were able to extract up to 127 W/cm(2) heat flux from a hot spot, and 50 W/cm2 heat flux in steady state continuous operation from the entire heated surface. The obtained Nusselt number correlations fall between two previously proposed correlations for laminar flow in rectangular microchannels. Friction factor results are also in agreement with the laminar theory with slight deviations

NANO AKIŞKAN GEÇİŞLİ MİKROKANALLI ISI ALICILARIN MEMS TEKNOLOJİSİ İLE ÜRETİMİ VE MİKROÇİP SOĞUTULMASINDA KULLANIMI

Bu proje kapsamında, yüksek alan/hacim oranları sayesinde geleneksel hava soğutma yöntemlerine göre çok daha etkin soğutma sağlayan mikrokanallı ısı alıcıların mikroçip soğutulmasındaki performansları incelenmiştir. Literatürde sunulan örneklerden farklı olarak, CMOS (Complementary Metal Oxide Semiconductor: Bütünleyici Metal Oksit Yarıiletken) entegre devre tasarım süreci ile uyumlu, özgün bir MEMS üretim tekniği kullanılarak, monolitik (tek tabanlı) bir mikrosoğutma sistemi elde edilmiştir. Bu sayede, CMOS uyumlu mikro-soğutma sistemlerinin, entegre devreleriyle birlikte üretilmesinin yolu açılmıştır. İlk test sonuçları ışığında, soğutma kapasitesini artırmak amacıyla mikrokanalların tasarımları geliştirilmiş, üretim yinelenmiştir. Soğutma deneyleri, mikrokanalların altına yerleştirilen, birim alan başına ürettiği ısı miktarları bilinen mikro ısıtıcılar ile gerçekleştirilmiştir. Soğutucu akışkan olarak öncelikle de-iyonize su kullanılmış; noktasal ısı kaynağını temsil eden devrelerden 127 W/cm2’ye, tamamı ısıtılan devrelerden 75 W/cm2’ye kadar ısı akısı sistemlerden uzaklaştırılabilmiştir. Nusselt sayısı ve sürtünme katsayısının Reynolds sayısına göre değişimi, literatürde benzer koşullar için verilen sonuçlarla uyum göstermiştir. Deneylerin son aşamasında suyun yanında, gümüş ve altın nanoparçacıklar içeren nano akışkanlar kullanılmıştır. Mekanizması tam olarak bilinmemekle birlikte, nano akışkanlar, kendilerini oluşturan temel akışkanlara oranla çok daha yüksek ısıl iletkenlikleri ve artan ısı transfer yüzey alanı sayesinde mikrokanallarla ortamdan uzaklaştırılan ısı miktarında önemli ölçüde artış sağlayabilmektedirler. Bu çalışma ile, nano akışkanların mikrokanallı ısı alıcılar ile kullanıldıklarında gösterdikleri performans da incelenmiştir

Nano-akışkan ısıl iletkenlik ölçümleri için bir deney düzeneğinin geliştirilmesi

Nanoakışkan, nanometre boyutundaki parçacıkların, su, etilen glikol ve benzeri bir baz akışkan içindeki süspansiyonu olarak tanımlanabilir. Nanoakışkanlar günümüzde ticari veya araştırma amaçlı olarak üretilmekte, elektronik soğutma, hızlı soğutma ısıl işlemi, mikro-biyo-sistemlerde akış, triboloji ve yağlama mühendisliği gibi çeşitli alanlarda kullanılmaktadır. Metal nanoparçacıklar içeren nanoakışkanlar, bir ısı değiştiricide kullanıldıklarında, baz akışkanlara göre daha iyi ısı transfer performansı göstermektedirler. Isı transferindeki bu artış, artan ısıl iletkenliğe, küçük boyutlu çok sayıda parçacığın sağladığı ısı transfer alan artışına, ve Brown hareketine bağlanmaktadır. Isı transfer artışını doğru değerlendirebilmek için, nano-akışkan üreticilerinin çoğu zaman bilgi sahibi olmadığı, ısıl iletkenlik, özgül ısı, viskozite gibi özelliklere ihtiyaç duyulmaktadır. Nanoakışkanların ısıl iletkenlik ölçümleri için çok sayıda teorik yöntem geliştirilmiştir. Daha az sayıdaki deneysel ölçümler ise genellikle birbiri ile ve teori ile çelişen sonuçlar ortaya koymaktadır. Bu çalışma ile nanoakışkanların ısıl iletkenliklerini ölçmeye yönelik bir deney düzeneğinin tasarım, üretim ve testlerinin gerçekleştirilmesi planlanmaktadır