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Fig.1 shows a permanent magnet bistable actuator operated by switching the current in alternate directions. It is characterised by long air gaps, and, for mechanical reasons, the cross‐section of the moving part (armature) is much smaller than those of other parts. These features make the magnetic field problem essentially 3‐dimensional, although the main flux path is confined to the longitudinal (x,y) plane. The amount of detail requires a 2D mesh of about 3000 elements in this cross‐section and about 500 elements in the transvers cross‐section, so that a full 3D solution would require a substantial calculation. The dynamic force characteristic requires a magnetic field distribution for each level of current in the coil and each position of the armature, thus creating strong incentives to use 2D approximations.

The effects of Opuntia ficus indica (OFI) cladodes on uricemia level, endothelial dysfunction and oxidative damage were studied in young rats fed a cafeteria diet (CD).

A total of 16 young male Wistar rats (weighing 110 ± 20 g and four weeks old) were divided into two homogenous groups. The first group received a CD containing 50% of hyperlipidic diet and 50% of junk food mix (processed mix: hyper-fat, hyper-salted and sweetened) (CD group), and the second group (CD + OFI nopalitos) received the same diet supplemented with 50 g of fresh OFI nopalitos (young cladodes) for 30 days.

OFI nopalitos regulate the hyperuricemia, improve the endothelial dysfunction by raising the bioavailability of nitric oxide(NO) and reduce prooxidant markers by reducing lipid peroxidation and protein oxidation (p < 0.05) and boosting antioxidant capacity and enhancing the antioxidant enzymes activities (p < 0.05) in blood and aorta tissues of rats early fed with a high-fat diet /junk food.

By-products of OFI have specific functional properties that may be beneficial in metabolic disorders and offer a better alternative with an economic and sustainable development perspective.

By-products of OFI highlight potential functional properties mainly based on its potent antioxidant capacity. By-products of OFI can be used as a promising nutraceutical resource to prevent various metabolic disorders in relation with cardiovascular diseases or hyperuricemia in subjects consuming junk food and or living in the Western society to reach the objectives of health policy and maintain a sustainable health system development.

The purpose of this study was to determine the effects of whole oat, oat bran and refined oat incorporation in a high-fat diet (HFD) on cardio-metabolic risk biomarkers in rats with type 2 diabetes mellitus (T2DM).

T2DM was induced by feeding male rats with an HFD for 10 weeks, followed by a low dose of streptozotocin. T2DM rats were then divided into four homogeneous groups. Three groups consumed an HFD containing 45 per cent (g/100 g diet) whole oat, oat bran or refined oat. The fourth untreated group (control) received the HFD.

The results showed that whole oat and oat bran, compared with refined oat and control, effectively reduced food intake (p < 0.007), arterial blood pressure (p = 0.0001), glycemia (p < 0.001), insulinemia (p < 0.01), glycosylated haemoglobin (p < 0.001) as well as homeostasis insulin resistance (HOMA-IR) (p < 0.001). They also improved blood lipid levels and reverse cholesterol transport by reducing serum total cholesterol (p = 0.0001), triacylglycerols (p < 0.05), very-low- (p = 0.0001) and low-density lipoproteins cholesterol contents (p < 0.02) increasing lipids (p < 0.002) and cholesterol excretion (p = 0.0001), and high-density lipoprotein cholesteryl esters (HDL₂-CE) concentrations (p = 0.0001) and stimulating lecithin: cholesterol acyltransferase (LCAT) activity (p = 0.0001). Moreover, they attenuated lipid peroxidation by increasing paraoxonase-1 (PON-1) atheroprotective activity (p < 0.05).

In T2DM rats, whole oat and particularly, its bran incorporated into an HFD improves arterial blood pressure, glycemic balance and lipid metabolic pathway by reducing hypertriglyceridemia and hypercholesterolemia and increasing atheroprotective activities of LCAT and PON-1. In contrast, refined oat accentuates the risk factors associated with diabetes.

The purpose of this study was to investigate the effects of prickly pear (Opuntia ficus indica (OFI)) nopalitos on body weight, food consumption, arterial blood pressure, glucidic homeostasis, cholesterol metabolic pathway and tissues redox status in type 2 diabetic (T2D) rats fed a high-fat diet (HFD).

Rats were fed by a HFD containing 30 per cent sheep fat for 10 weeks, after which they were rendered diabetic by an injection of a low dose of streptozotocin (STZ) (35 mg/kg). The diabetic rats were then divided into two groups. The first group consumed the HFD supplemented with 5 per cent (g/100 g diet) of freeze-dried OFI nopalitos (HFD-OFI), and the second group received the HFD without supplementation (HFD).

OFI nopalitos treatment decreased significantly arterial diastolic (−20%; p = 0.0001) and systolic (−16%; p = 0.0001) pressures, glycemia (−14%; p = 0.03), insulinemia (−50%; p = 0.04), glycated hemoglobin (−49%; p = 0.003), homeostasis model assessment insulin resistance (−67%; p = 0.03), cholesterolemia (−31%; p = 0.003), very-low and low-density lipoprotein cholesterol (−38%; p = 0.002 and −63% p = 0.0002, respectively); thiobarbituric acid reactive substances and lipid hydroperoxide contents, respectively, in liver (−26% p = 0.02, −20% p = 0.02), adipose tissue (−30% p = 0.002, −25% p = 0.001), muscle (−29% p = 0.003, −25% p = 0.008) and kidney (lipid hydroperoxides only (−28%; p = 0.001) but increased high-density lipoprotein (HDL₂) cholesteryl esters (+61%; p = 0.0001), serum lecithin: cholesterol acyltransferase activity (+21%; p = 0.006) and antioxidant enzymes activities (superoxide dismutase, glutathione peroxidase and catalase) of some tissues (liver, adipose tissue, muscle and kidney).

Freeze-dried OFI nopalitos improves arterial blood pressure, glycemic control, metabolic pathway of cholesterol and redox status in T2D rats.

This paper aims to evaluate the protective potential of prickly pear cactus fresh cladodes (opuntia ficus indica (OFI)) on glycemic disorders, dyslipidemia, prooxidant/antioxidant stress biomarkers and reverse cholesterol transport (by evaluating the activity of lecithin-cholesterol acyltransferase (LCAT)) and paraoxonase (PON1) in rats prematurely exposed to cafeteria diet (CD).

Sixteen young rats were divided into two groups fed CD containing 50 per cent of hyperlipidic diet (HLD) and 50 per cent of junk food mix supplemented or not with 50 g of fresh young cladodes of OFI to 100 g of CD, during 30 days.

OFI cladodes supplementation decreased significantly body weight (p < 0.001), food intake (p < 0.05), adipose tissue weight (p < 0.01), fasting glycemia and glycosylated hemoglobin (p < 0.01), homeostasis model assessment (HOMA-IR) and insulinemia (p < 0.001), levels of cholesterol (C) (p < 0.05) and triacylglycerols (TG) (p < 0.01) in serum and in very low-density lipoproteins (VLDL-C p < 0.05 and VLDL-TG p < 0.01) and improves reverse cholesterol transport by increasing high-density lipoprotein cholesteryl-esters concentrations (p < 0.001) and by stimulating LCAT activity. Moreover, they attenuated lipid peroxidation in VLDL and low-density lipoproteins by increasing atheroprotective activity of PON-1 and in liver and adipose tissue by enhancing enzymatic antioxidant defence.

The young cladodes of OFI because of their antiobesity benefits could constitute a novel functional ingredient in pharmaceutical and nutraceutical applications.

Young cladodes of OFI in rat precociously submitted to a hyperlipidic diet/junk food (cafeteria model) seem to prevent metabolic disorders associated with obesity.

The purpose of this study was to investigate the impact of replacing two different fats on dyslipidemia, glycemic balance and adipose tissue redox status in obese rats.

Obesity was induced by feeding a high-mutton-fat diet during three months. An experimental group (n = 24) was divided into two groups that were fed during one month, 20 per cent of margarine or sardine oil. At Day 30, six rats from each group were sacrificed and the remaining rats were then subjected to a change in diet for one month: margarine was replaced by sardine oil and inversely, and then the rats were sacrificed. Three other groups (n = 6), each fed during two months, 20 per cent of margarine, sardine oil or mutton fat, served as controls.

Substitution of sardine oil by margarine compared to control sardine oil had increased triacylglycerols (TGs), glycosylated hemoglobin (HbA1c) and isoprostanes (IsoPs) values, but decreased thiobarbituric acid reactive substances (TBARS) and superoxide dismutase activity. Replacing margarine by sardine oil compared to control margarine reduced total cholesterol, TG, HbA1c, TBARS and IsoP contents but enhanced glutathione reductase and peroxidase activities. Nevertheless, comparing with the mutton fat, the two substitutions had improved glycemic and lipidic abnormalities and attenuated lipoperoxidation by enhancing enzymatic antioxidant defense. These favorable effects were better when margarine was replaced by sardine oil.

Substituting margarine with sardine oil seems to attenuate beneficial cardiometabolic risk markers associated to obesity and potentiate efficiency adipose tissue against the oxidative stress induced by the obesogenic diet.

This study focuses on the CFD numerical simulation and analysis of the vortex stacking problem at the top of the impeller of a high-speed fuel pump, mainly using LCS and entropy production theory to visualize the vortex at the top of the impeller as well as quantitatively analyzing the energy loss caused by the vortex at the top of the impeller. By combining the two methods, the two are well verified with each other that the stacking problem of the vortex at the top of the impeller and the location of the energy loss caused by the vortex are consistent with the vortex location. Such a method can reveal the problem of vortex buildup at the top of the lobe well, and provide a novel guidance idea for improving the performance of high-speed fuel pumps.

Based on CFD numerical simulation and analysis, this study mainly uses LCS and entropy production theory to visualize the top vortex of the impeller. Through the combination of the two methods, the accumulation problem of the top vortex of the impeller and the location of the energy loss caused by the vortex can be well revealed.

(1) The CFD numerical simulation analysis of the high-speed fuel pump is carried out, and the test is conducted to verify the numerical simulation results. The inlet and outlet pressure difference? P is used as the validation index, and the error analysis shows that the error between numerical simulation and test results is within 10%, which meets our requirements. Therefore, we carry out the next analysis with the help of CFD numerical simulation. By analyzing the full working condition simulation, its inlet and outlet differential pressure? P and efficiency? Are evaluated. It is found that its differential pressure decreases with the flow rate and its efficiency reaches its maximum at Qv = 9.87 L/s with a maximum efficiency of 78.32%. (2) We used the LCS in the analysis of vortices at the top of the impeller blades of a high-speed fuel pump. One of the metrics used to describe the LCS in fluid dynamics is the FTLE. The high FTLE region represents the region with the highest and fastest particle trajectory stretching velocity in the fluid flow. We performed a cross-sectional analysis of the FTLE field on the different height surfaces of the impeller on 25% Plane, 50% Plane, and 75% Plane, respectively. And a quarter turn of the rotor rotation was analyzed as a cycle divided into 8 moments. It is found that on 25% Plane, the vortex at the top of the lobe is not obvious, but there are high FTLE values on the shroud surface. On 50% Plane, the lobe top vortex is relatively obvious and the number of vortices is three. The vortex pattern remains stable with the rotating motion of the rotor. At 75% Plane, the lobe top vortex is more visible and its number of vortices increases to about 5 and the vortex morphology is relatively stable. The FTLE ridges visualize the vortex profile. This is a good guide for fluid dynamics analysis. (3) At the same time, we use the entropy production theory to quantitatively analyze the energy loss, and define the entropy production rate Ep. Through the entropy production analysis of the impeller shroud surface and the suction surface of the pressure surface of the blades at eight moments, we find that the areas of high energy loss are mainly concentrated in the leading and trailing edges of the blades as well as in the shroud surface close to the leading edge of the blades, and the value of the entropy production rate is up to 106 W/m3/K. The areas of high energy loss in the leading edge of the blades as well as the trailing edge show a curved arc, and the energy loss is decreasing as it moves away from the shroud surface and closer to the hub surface. The high energy loss areas at the leading and trailing edges of the blades are curved, and the energy loss decreases as they move away from the shroud surface and closer to the hub surface. The energy loss at the pressure surface of the blade is relatively small, about 5 × 105 W/m3/K, which is mainly concentrated near the leading edge of the blade near the shroud surface and the trailing edge of the blade near the hub surface. Such energy loss corresponds to the vortex LCS at the top of the impeller, and the two mirror each other.

This study focuses on the CFD numerical simulation and analysis of the vortex stacking problem at the top of the impeller of a high-speed fuel pump, mainly using LCS and entropy production theory to visualize the vortex at the top of the impeller as well as quantitatively analyzing the energy loss caused by the vortex at the top of the impeller. By combining the two methods, the two are well verified with each other that the stacking problem of the vortex at the top of the impeller and the location of the energy loss caused by the vortex are consistent with the vortex location. Such a method can reveal the problem of vortex buildup at the top of the lobe well, and provide a novel guidance idea for improving the performance of high-speed fuel pumps.

This study was aimed to develop and evaluate nutritional efficacy and bio-efficacy of food products from plantain, soycake, rice-bran and oat-bran flour.

The flour samples were blended as follows: plantain 70% and soycake 30% (PS); plantain 65%, soycake 30% and rice bran 5% (PSR); plantain 65%, soycake 30% and oat bran 5% (PSO); and plantain 60%, soycake 30%, rice bran 5% and oat bran 5% (PSRO). Antioxidant and nutritional properties of the blended foods and controls (100% plantain and Cerolina) were determined.

Protein (16.2–19.4 g/100g) and biological values (98.5–99.3%) of the food samples were significantly (p = 0.03) higher than 100% plantain (5 g/100g, 31.6%) and Cerolina (17.9 g/100g, 98.3%). Pack cell volume (36.2–42%), serum protein (7.3–9.3 mg/dL), urea/creatinine (1.1–2.8) and aspartate-aminotransferase/alanine-aminotransferase ratio (0.9–1) of the foods were significantly (p = 0.03, 0.01, 0.02 and <0.01, respectively) higher than 100% plantain (28%, 1.6 mg/dL, 4.6 and 0.8) and Cerolina (46%, 4.9 mg/dL, 3 and 0.73). In vivo antioxidant activity of the food samples decreased from PSRO to PSO, PSR and PS, respectively and were higher than control samples. Nutritional performance of formulated foods in rats was similar to that of Cerolina, but higher than in 100% plantain. Cerolina and 100% plantain were rated higher in overall acceptability than formulated foods; however, PSO was most preferred followed by PSRO for the formulated foods.

The study established that PSRO was rated best in terms of nutrition, growth performance and antioxidant activities. Hence, this food may be suitable as functional food to prevent malnutrition and oxidative stress.

This paper aims to evaluate systolic blood pressure (SBP), serum sodium/potassium levels and cardiac antioxidants after Artemisia herba-alba oral administration in spontaneous hypertensive rats (SHR).

Hypertension is a silent killer disease. The SHR model was used in this study due to the similarity of high blood pressure in human and rat. The SBP, serum sodium and potassium, urinary sodium and potassium, cardiac antioxidants and heart histology were examined in SHR after oral administration with 10 and 20% of the LD₅₀ of Artemisia herba-alba during four weeks.

The LD₅₀ of Artemisia herba-alba was found to be 1000 mg/kg. Doses of 100 mg/kg (10% LD₅₀) and 200 mg/kg (20% LD₅₀) were considered in the present study. The oral administration of SHR rats with Artemisia extract at 100 and 200 mg/kg decreased (p < 0.01) the body weights, SBP and serum sodium and potassium. Meanwhile, cardiac superoxide dismutase and gluthatione peroxidase were increased in SHR-treated rats. Histology of SHR cardiac tissues showed tissue degenerative but oral intake of 100 and 200 mg/kg artemisia exhibited normal muscle fibers, acidophilic cytoplasm and central nuclei.

The cardiovascular diseases are the first reason for high death rate in Western countries and collapsing economies due to hypertensive patients suffering high health-care costs. The advantage of hypertension Herba l treatment occurred due to its cheap and available source. Artemisia herba-alba leaves restored SBP, attenuated serum sodium/potassium levels and prevented cardiac oxidative stress in SHR.

Obesity is a major risk factor for chronic renal fibrosis and kidneys’ structural and inflammatory impairments. This study aims to examine the possible therapeutic effects of vitamin D supplementation against renal inflammatory and kidney’s structural fibrosis and degeneration.

Forty male Wistar rats were divided into two groups for 16 weeks: normal diet (ND) and high-fat diet (HFD); then, each group was subdivided into two groups including ND, ND + vitamin D and HFD, HFD + vitamin D. Vitamin D supplementation was done for five weeks at 500 IU/kg dosage. Renal tissue concentrations of tumor necrosis factor (TNF)-α, interleukin 6, interleukin 1 beta, monocyte chemoattractant protein (MCP)-1 and transforming growth factor-beta (TGF-β), serum values of lipids, markers of glucose homeostasis and urea, creatinine and uric acid and renal tissue histological and structural changes were determined.

HFD feeding caused remarkable histological and structural changes including higher TNF-α, MCP-1 and TGF-β concentrations in renal tissues of rats, whereas vitamin D has potent anti-inflammatory effects (P = 0.036, 0.047 and 0.02, respectively). Vitamin D administration also reduced urea and uric acid concentrations (P = 0.023 and 0.049, respectively). Moreover, vitamin D reduced glomerulomegaly, reduced lipid accumulation and limited dilated Bowman’s space in rats and improved glycemic status by increasing insulin (P = 0.04) and reducing insulin resistance (P = 0.006).

The current study has some limitations. It was better to measure the level of inflammatory cytokines’ expression in the kidney tissues. Additionally, the measurement of baseline values of inflammatory cytokines was not possible because of the possibility of animals’ drop-out.

According to the study findings, vitamin D treatment in the current report showed a significant therapeutic role in reducing inflammation, improving glycemic and lipid abnormalities and structural and histological modifications in renal tissues of rats. These findings have a great value because after confirming in a human model, vitamin D can be suggested as a potential therapeutic tool in clinical practice.

After being confirmed by other animal or human researches, the results of the current work could have great social implications by reducing the prevalence of obesity-related renal complications and highlighting the beneficial roles of vitamin D.

To the best of the authors’ knowledge, this is the first study to investigate the histological and inflammatory changes in the kidneys and metabolic parameters in the HFD induced rats and also clarified the therapeutic roles of vitamin D in ameliorating the inflammatory, histological, metabolic and functional changes in the kidneys of obese rats.