Index Of Absorption Research Articles

Thick Ascending Limbs (TALs)-specific deletion of ALMS1 (Alstrom syndrome 1) increases surface NKCC2 expression and NaCl reabsorption in the TAL

The regulation of NKCC2 mediated NaCl reabsorption in Thick Ascending Libs (TALs) is essential to salt homeostasis and blood pressure regulation. Previously, our lab showed that NKCC2 activity is regulated by membrane traffcking and inhibiting endocytosis enhanced surface NKCC2 expression and NaCl reabsorption. We also found that ALMS1, a protein mutated in Alström syndrome, is expressed in TALs. Whole animal gene deletion of ALMS1 caused hypertension, and inhibits NKCC2 endocytosis, increasing its surface expression and renal NaCl reabsorption. Little is known about additional functions of ALMS1, however, global gene deletion of ALMS1 induces obesity, and that, in turn may affect TAL and NKCC2 function. We hypothesized that ALMS1 is a part of protein complex that binds apical NKCC2 in TALs and promotes its endocytosis. To dissect the specific role of ALMS1 in TALs, without interference of systemic effects, we studied surface NKCC2 expression and TAL mediated Na transport after inducible deletion of ALMS1 in TALs. To do this, we generated a loxP flanked exon 7 ALMS1 transgenic mouse line, that we crossed with TAL specific inducible Umod-ERT2 Cre mice (Umod-ALMS1 KO). 3 weeks after inducing Cre expression with tamoxifen, ALMS1 expression in TAL suspensions decreased by 85% (p<0.01) (n=5). In Umod-ALMS1 KO TALs the surface to total NKCC2 ratio, was increased by 37±15% compared to control floxed ALMS1 (p<0.01) (n=5). Recombinant ALMS1 (GST-Carboxyl terminus-ALMS1), or immunoprecipitation of ALMS1, pulled down NKCC2 from TAL lysates (n=3), suggesting that the mechanism by which ALMS1 regulates surface NKCC2 involves protein-protein interactions. Three weeks after inducing ALMS1 deletion, we measured bumetanide-induced natriuresis (4h) as an index of NKCC2-mediated NaCl absorption. We found that bumetanide induced UNa excretion was enhanced in Umod-ALMS1 KO, compared to control (control: 110±7 vs Umod-ALMS1 KO: 173±26 μmols Na/4h, p<0.01). We conclude that ALMS1, binds NKCC2 to regulate its surface expression. Depletion of ALMS1, specifically in the TAL enhances surface NKCC2 and TAL NaCl reabsorption. Our data indicate that regulation of the ALMS1-NKCC2 interaction in the TAL is important for renal NaCl reabsorption. Decreased ALMS1 function or expression increased TAL NaCl reabsorption and this may contribute to the hypertension and kidney disease that is associated with SNPs in the ALMS1 gene in the general population, or in patients with Alstrom Syndrome. NIH R01, Henry Ford Fund. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Study on Reducing Water Absorption of Recycled Aggregates (RAs) by Microbial Mineralization.

Crushing waste concrete and using it directly as RAs has the disadvantages of high porosity and high water absorption. To achieve the reuse of resources, the researchers use microbial mineralization methods to further reinforce RAs. In this paper, the effect of the microbial carbonic anhydrase mineralization method on the water absorption of RAs was investigated, and the macroscopic analysis was performed by determining the indexes of water absorption and apparent density of RAs before and after the modification, and the microscopic analysis of RAs by using the methods of SEM, XRD, DSC, and EDS as well. According to the microscopic analysis, the mineralization products of microorganisms are calcium carbonate crystals, and with the increase in microbial liquid concentration, the water absorption rate of RAs shows a trend of decreasing and then increasing, and it can be found through the microscopic morphology that abundant mineralization products attached to the surface of the aggregate lead to the surface of the aggregate becoming rougher and more porous. The method of soaking the RAs in 3% bacterial solution and 0.1 mol/L calcium acetate solution followed by carbonation with 20% CO2 resulted in a 4.85% reduction in water absorption.

Spatial Analysis of Changes in Normalization Differences Vegetation Index in Protected Forest Areas of South Lore District, Poso Regency

Detection of changes in vegetation density generally uses the vegetation index parameter. The value of the vegetation index can provide information on the proportion of vegetation cover, live plant index, plant biomass, cooling capacity, and estimation of carbon dioxide absorption. This study aims to analyze changes in the level of vegetation density using Sentinel 2-A imagery in the protected forest area of South Lore District. This study used the method of calculating the Normalized Difference Vegetation Index (NDVI) to identify changes in density over 5 years. The results of the NDVI analysis are the largest in the range of -0.92960 to 0.871725. The vegetation density class in the Protected Forest Area of South Lore District in 2017 is in the dense class with an area of 15,322.24 Ha or around 47.66%, while the smallest in the non-vegetation class, which is 103.11 Ha or 0.32%, while the largest vegetation density class is in the Protected Forest Area of South Lore District in 2022, namely in the medium/quite dense class with an area of 19,948.18 Ha or 62.01% while the smallest in the non-vegetation class of 219.17 Ha or 0.68%. The largest increase in area was in the moderate/quite dense class of 4,892.33 Ha or 15.20% while the largest decrease in area was in the dense class with an area of 6,651.16 Ha or 20.67% of the total area of the Protected Forest Area of South Lore District.

The Linear Optical Properties of Rhodamin110 Organic Dye Doped with Metal Nanoparticles

Background:
 Laser dyes are unsaturated hydrocarbon compounds that have the advantage of having double or triple bonds coupled with carbon atom chains. This system benefits from light absorption in the visible range (200–700 nm) and the transmission spectrum of absorption in the visible range
 Materials and Methods:
 This research has focused on the effect of Adding ethanol solution to rhodamine110 dye with different concentrations, the linear properties (permeability, absorbance) of Rhodamine110 dye were studied as it was dissolved in ethanol to prepare solutions with concentrations (0. 01, 0.03, 0.05) and at room temperature
 Results:
 The absorbance A of Rhodamine110 dye with ethanol was calculated for the above concentrations, respectively, as well as and the transmittance T was calculated for the above concentrations, respectively, to obtain curves and rhodamine110 dyes were mixed with nanomaterials to improve the properties of the dyes
 Conclusion:
 In this study, According to Beer-Lambert's rule, increasing the dye concentration will increase absorbance, which will raise the linear optical coefficients (refractive index and coefficient of absorption) for all produced samples. The probability of electronic transitions will definitely be affected by the type of solvent., and this has an impact on linear optical characteristics, particularly the positions and width of the absorption spectra. And the addition of nanomaterials added better improvements to the dye. The results showed that the highest linear properties appeared when the silver nanomaterials with rhodamine110 dye

Nephron-specific deletion of ALMS1 (Alstrom syndrome 1) increases surface NKCC2 expression and NaCl reabsorption in the Thick Ascending Limb

Mutations in the ALMS1 gene in humans cause Alström syndrome, characterized by progressive metabolic alterations that include obesity, hypertension, and chronic kidney disease (CKD). SNPs in the ALMS1 gene in the general population are associated with lower GFR, hypertension and metabolic syndrome. ALMS1 is widely expressed where it localizes to endosomes, centrosomes and the base of cilia. Our lab has previously shown that ALMS1 is expressed in renal tubules of the Thick Ascending Limb (TAL) where NKCC2 is the primary apical NaCl transporter. Whole animal gene deletion of ALMS1 increases blood pressure, and inhibits NKCC2 endocytosis, increasing its surface expression and renal NaCl reabsorption. However, whole animal ALMS1 KO rats or mice develop obesity, affecting the interpretation of organ-specific data. We hypothesized that ALMS1 is a part of protein complex that binds apical NKCC2 in TALs and promotes its endocytosis. To study the role of ALMS1 in the nephron without influence of obesity we generated a loxP flanked exon 7 ALMS1 transgenic mouse line, that we crossed with nephron specific inducible Pax8-rtTA Cre mice (Pax8-ALMS1 KO). 4 weeks after inducing Cre expression with doxycycline (2mg/ml in 2% sucrose), ALMS1 expression in TAL suspensions decreased by 75% (p<0.01). To study the role of ALMS1 in TAL function, we measured surface to total NKCC2 ratio, which was increased by 53±15% in TALs from Pax8-ALMS1 KO compared to control floxed ALMS1 (p<0.01). Recombinant ALMS1 (GST-Carboxyl terminus-ALMS1), or immunoprecipitation of ALMS1, pulled down NKCC2 from WT TAL lysates (n=3), suggesting that the mechanism by which ALMS1 regulates surface NKCC2 involves protein-protein interactions. 4 weeks after inducing Cre expression with doxycycline we measured bumetanide-induced natriuresis (4h) as an index of NKCC2-mediated NaCl absorption. We found that bumetanide induced UNa excretion was higher in Pax8-ALMS1 KO, compared to control (control: 115±19 vs Pax8-ALMS1 KO: 146±30 μmols Na/4h, p<0.05). Since whole animal ALMS1 deletion induced hypertension, we measured systolic blood pressure (SBP) by tail cuff one month after inducible deletion of ALMS1 or in floxed ALMS1 mice treated with doxycycline as controls. Baseline SBP in normal Na diet (0.4%) was similar between strains. However, SBP increased by 12±3 mmHg in Pax8-ALMS1 KO, but not in control floxed ALMS1 littermates after 9 days of high Na diet (WT: 100±10, Pax8-ALMS1 KO: 115±11 mmHg, p<0.05 from baseline, n=4). We conclude that ALMS1, binds NKCC2 to regulate its surface expression. Depletion of ALMS1 in the nephron enhances surface NKCC2, TAL NaCl reabsorption, and induces salt-sensitivity of blood pressure. Our data indicate that regulation of the ALMS1-NKCC2 interaction in the TAL is important for renal NaCl reabsorption and regulation of blood pressure. Funding: NIH R56DK131114, Henry Ford Fund This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Improved Extrusion Cooking Technology: A Mini Review Of Starch Modification

ABSTRACT In the literature, there are several articles that worked with what they called improved extrusion cooking technology (IECT), which is an innovative machine for the modification of starch, obtained from the traditional screw extruder. This review focused on the advances in the application of the IECT used in food processing, from the perspective of the results obtained in some physicochemical properties. Interesting results have been obtained, such as significant starch gelatinization at a moisture content of 70% and a screw speed of 37 rpm. In the index of water absorption and water solubility, a variety of results are obtained, depending on the process conditions. The IECT has potential applying it not only to the modification of starch, but also comparing it with other types of extruders, with the intention of increasing and diversify the results for their potential use in food.

Հայաստանի Հանրապետությունում տեխնոլոգիաների և գիտելիքի կլանման ու փոխանցման հիմնախնդիրները ու դրանց լուծման ուղիները միջազգային փորձի համատեքստում / Problems of Assimilation and Transfer of Technologies and Knowledge in the Republic of Armenia and Ways to Solve Them in the Context of International Experience

The purpose of this study is to examine the positioning of RA in the processes of knowledge transfer and absorption currently taking place in the world. In this context, several problems were identified in the work. First of all, the experience of those countries that have recorded remarkable successes in the transfer and assimilation of knowledge, which have been recorded at the actual level of internationally calculated indices of absorption and transfer of knowledge, has been studied. The next step was to select them from the countries that have achieved success in the process of assimilation and transfer of knowledge, which, according to specific criteria, are close to Armenia. During the analysis, Armenia and isolated countries were compared not only by the actual levels of indicators of assimilation and transfer of knowledge but also by differences in the indicators of the above-mentioned indices. In the course of the conducted research, comparative and theoretical methods were used, including various graphs and theoretical positions. A number of results were obtained in the research. Special attention was paid to the factors, which mainly hinder the process of forming an innovative economy in Armenia in the context of the assimilation and transfer of knowledge. It became clear that there is a need for a balanced policy approach to address the existing obstacles in the above-mentioned processes.

Extraction of Natural Pigment from Ocimum tenuiflorum Using Different Polar Solvents and Their Nonlinear Optical Characteristics.

Herein, we report the extraction, characterization, linear and third-order nonlinear optical (TONLO) features of the natural pigment from Ocimum tenuiflorum leaves using different polar solvents. The polar solvents such as, ethanol, acetone, methanol and dimethyl sulfonate (DMSO) were used to extract the natural pigment from Ocimum tenuiflorum leaves. The effect of solvent on linear and TONLO properties of the natural pigment was studied and multi- parameter scale known as Kamlet-Abboud-Taft was used to analyse the solvent characteristics on solute molecule. The functional groups of the extracted natural pigments were examined via Fourier transform infrared (FT-IR) spectrometer. TONLO characteristics of the natural pigment was scrutinised by a continuous wave (CW) diode laser working at 650nm wavelength. The nonlinear refractive index (n2) and nonlinear coefficient of absorption (β) of the natural pigment was ascribed to the behavior of self-defocusing, saturable absorption (SA) and reverse saturable absorption (RSA). The TONLO susceptibility (χ(3)) of the natural pigment in polar solvents was found to be the order of 10-6 esu. The natural pigment extracted from Ocimum tenuiflorum leaves is a potential material for applications in nonlinear optical.

Simultaneous Evaluation of Dissolution and Absorption Study of Compound Danshen Tablets and Capsules Based on Cellular Electrical Sensing Model.

This study explores the dissolution mechanism and absorption process of compound Danshen tablets (CDTs) and compound Danshen capsules (CDCs) in vitro. Taking the cell index as the evaluation index of dissolution and absorption of multi-component solid preparations of CDTs and CDCs, it breaks through the idea of traditional research. We used real-time cell-based assay (RTCA) to provide a new idea and method for the consistency evaluation of traditional Chinese medicine (TCM) compound preparations. The drug dissolution and absorption simulation system (DDASS) was established to obtain the dissolution and absorption samples of compound Danshen solid preparations at different time points. The cell index (CI) of the sample to H9C2 cells was detected by RTCA technology, and the dissolution and absorption percentage were calculated based on this index to obtain the dissolution and absorption kinetics model. Meanwhile, one batch of tablets and one batch of capsules (batch numbers ZKC1816 and 202101001) were selected to conduct the overall animal pharmacodynamic experiment to verify the feasibility of drug effect evaluation with cell index as an indicator. The best fitting model of dissolution curves of each batch of CDTs and CDCs is the Weibull model. There was a good correlation (r > 0.86) between the dissolution-absorption-pharmacodynamic curve. Based on RTCA technology, we have established the comprehensive evaluation method for cell biology of compound Danshen solid preparations in line with the overall concept of TCM and a synchronous evaluation system of dissolution and absorption in vitro of new TCM compound solid preparations.

Comparison of hydration efficacy of carbohydrate-electrolytes beverages consisting of isomaltulose and sucrose in healthy young adults: A randomized crossover trial

Isomaltulose is a low glycemic and insulinaemic carbohydrate now used as an alternative sweetener in beverages. However, it remains unclear if hydration status may be impacted differently with the consumption of beverages containing isomaltulose as compared to sucrose, a common beverage sweetener. Thirteen young adults (7 women) consumed 1 L of a carbohydrate beverage (with low electrolyte content) containing either 6.5%-sucrose, 6.5%-isomaltulose, or water within a 15 min period. For each beverage, beverage hydration index (BHI, a composite measure of fluid balance after consuming a test beverage relative to water) was calculated from urine volume produced over a 3 h period following ingestion of the carbohydrate beverages relative to water. The change in plasma volume (ΔPV), blood glucose, and lactate concentrations were assessed every 30 min post-beverage consumption. Isomaltulose ingestion attenuated urine production as compared to water and sucrose (P ≤ 0.005) over the 3 h post-ingestion period. However, no differences were observed between sucrose and water (P = 0.055). BHI was 1.53 ± 0.44 for isomaltulose (P ≤ 0.022 vs. sucrose and water) and 1.20±0.29 for sucrose (P = 0.210 vs. water). A transient reduction in ΔPV was observed following the ingestion of the isomaltulose beverage (at 30 min, P = 0.007 vs. sucrose). Thereafter, no differences in ΔPV between beverages were measured. Increases in blood glucose and lactate, indices of absorption and utility of glucose, were delayed in the isomaltulose as compared to sucrose beverage. In summary, we demonstrated a greater BHI with a carbohydrate-electrolyte beverage containing isomaltulose as compared to sucrose. This may in part be attributed to a delayed absorption of isomaltulose reducing diuresis.

Aerosol delivery of inhalation devices with different add-on connections to invasively ventilated COPD subjects: An in-vivo study

Aerosol delivery to mechanically ventilated patients requires add-on connections to place the inhalation device within the ventilation circuit. The study aimed to evaluate the performance of Combihaler in dual limb invasive mechanical ventilation (IMV).A ventilator with a humidified dual limb circuit was adjusted to volume-controlled mode to imitate the adult breathing parameters. 24 (12 females) intubated chronic obstructive pulmonary disease (COPD) subjects had undergone the study. All patients were prescribed inhaled salbutamol dose delivered by either a metered-dose inhaler (pMDI) or vibrating mesh nebulizer (VMN). Each subject received salbutamol in four different inhalation device/connection conditions; pMDI+VMN+Combihaler, VMN+Combihaler, VMN+T-piece, and pMDI+T-piece. They were individually placed in the inspiratory limb at Y-piece. 5mg salbutamol was delivered by VMN with and without 2 pMDI puffs of salbutamol (100 µg), and 500µg was delivered by pMDI+T-piece. After aerosol delivery, two urine samples were collected from the patient; 30 min post-inhalation (USAL0.5) and cumulatively 24 h post-inhalation (USAL24) as indexes of lung deposition and systemic absorption, respectively. For the ex-vivo study, a collecting filter was placed before an endotracheal tube (ETT) to collect the delivered inhalable dose. In-vitro aerodynamic characteristics were also investigated.pMDI+VMN+Combihaler delivered more salbutamol to the lung and the ex-vivo filter than VMN+T-piece (p˂0.05, p≤0.01, respectively). VMN delivered a higher salbutamol amount to the lung, systemically, and the ex-vivo filter than pMDI+T-piece (p˂0.001). pMDI+VMN+Combihaler and VMN+Combihaler delivered aerosols with a less mass median aerodynamic diameter (MMAD) and higher fine particle fraction (FPF) compared to VMN+T-piece (p≤0.01 for MMAD, p˂0.01 for FPF) and pMDI+T-piece (p˂0.01 for both MMAD and FPF).Results of the study showed that pMDI+VMN+ Combihaler delivered more salbutamol than VMN+T-piece in IMV and demonstrate that 5 puffs (500-µg) of salbutamol with pMDI+T-piece has a lower aerosol delivering power at the level of USAL0.5, USAL24, and the ex-vivo inhalable dose than 5 mg nebulized salbutamol by VMNs in IMV.

Calcium amendment for improved germination, plant growth, and leaf photosynthetic electron transport in oat (Avena sativa) under NaCl stress.

Calcium (Ca2+) is an essential nutrient element for plants as it stabilizes the membrane system structure and controls enzyme activity. To investigate the effects of Ca2+ on plant growth and leaf photosynthetic electron transport in oat (Avena sativa) under NaCl stress, oat seeds and plants were cultivated in nutrient solutions with single NaCl treatment and NaCl treatment with CaCl2 amendment. By measuring the seed germination rate, plant growth, Na+ and Cl- accumulation in leaves, ion leakage in seedlings and leaves, prompt chlorophyll a fluorescence (PF) transient (OJIP), delayed chlorophyll a fluorescence (DF), and modulated 820 nm reflection (MR) values of the leaves at different growth phases, we observed that Ca2+ alleviated the inhibition of germination and plant growth and decreased Na+ and Cl- accumulation and ion leakage in the leaves under NaCl stress. NaCl stress changed the curves of the OJIP transient, induced PF intensity at P-step (FP) decrease and PF intensity at J-step (FJ) increase, resulted in obvious K and L bands, and altered the performance index of absorption (PIABS), the absorption of antenna chlorophyll (ABS/RC), electron movement efficiency (ETo/TRo), and potential maximum photosynthetic capacity (FV/FM) values. With the time extension of NaCl stress, I1 and I2 in the DF curve showed a decreasing trend, the lowest values of MR/MRO curve increased, and the highest points of the MR/MRO curve decreased. Compared with NaCl treatment, the extent of change induced by NaCl in the values of OJIP, DF and MR was reduced in the NaCl treatment with CaCl2 amendment. These results revealed that Ca2+ might improve the photosynthetic efficiency and the growth of salt-stressed plants by maintaining the integrity of oxygen-evolving complexes and electron transporters on the side of the PSI receptor and enhancing the relationship between the functional units of the photosynthetic electron transport chain. The findings from this study could be used for improving crop productivity in saline alkali lands.

Study of Third-order Nonlinear Optical Properties of Basic Violet 3 Dye in Polar Protic and Aprotic Solvents.

The present work aims to study of third-order nonlinear optical (TONLO) behavior of basic violet 3 dye dissolved in polar protic and aprotic solvents, namely, ethanol, 1-propanol, acetone and dimethyl sulfonate (DMSO), respectively. The polarity of the solvent used to have a substantial impact on the linear and TONLO properties of the dye sample. The dye exhibits self-defocusing nonlinearity due to thermally induced nonlinear refractive index and nonlinear absorption coefficient reveals the character of both saturable and reverse saturable absorption (RSA). The order of magnitude of nonlinear refractive index (n2) and nonlinear coefficient of absorption (β) of dye sample was determined to be 10-7 cm2/W and 10-3cm/W, respectively. The real and imaginary factors of the TONLO susceptibility of basic violet 3 dye were measured to be the power of 10-5 esu. The obtained results reveal that the dye sample seems to have the potential candidate for use in various photonics and optoelectronics applications.

Berberis lyceum and Fumaria indica: in vitro cytotoxicity, antioxidant activity, and in silico screening of their selected phytochemicals as novel hepatitis C virus nonstructural protein 5A inhibitors

Berberis lyceum and Fumaria indica are two Pakistani indigenous herbal medicines used to treat liver infections, including hepatitis C virus (HCV). This study aimed to evaluate the cytotoxicity, and antioxidant activity of these plant extracts and computationally screen their selected phytoconstituents as HCV NS5A inhibitors. The viability of HepG2 cells was assessed 24 h and 48 h post-treatment using colorimetric and dye exclusion methods. Antioxidant properties were examined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH), reducing power, and total antioxidant capacity assays. Seventeen known phytochemicals identified from each plant were docked into the active binding site of HCV NS5A protein. The top hit ligands were analyzed for their druglikeness properties and the indices of absorption, distribution, metabolism, elimination, and toxicity (ADMET). The results showed that both plant extracts were non-toxic (CC50 > 200 µg/ml). The IC50 values of DPPH-radical scavenging activity were 51.02 ± 0.94 and 62.91 ± 1.85 µg/ml for B. lyceum and F. indica, respectively. They also exhibited reducing power and total antioxidant capacity.The phytochemicals were identified as potent HCV NS5A inhibitors with good druglikeness and ADMET properties. Six of the docked phytochemicals exhibited higher binding scores (-17.9 to −19.2 kcal/mol) with HCV NS5A protein than the standard drug, daclatasvir (-17.2 kcal/mol). Molecular dynamics (MD) simulation confirmed the stability of two compounds, berbamine and paprafumine at 100 ns with active site of HCV NS5A protein. The identified compounds through molecular docking and MD simulation could have potential as HCV NS5A inhibitor after further validation. Communicated by Ramaswamy H. Sarma

Evaluation of the drying effect on some properties of cidra flour Sechium edule (Jacq) Sw

Alternative flours from plant sources such as cidra, are options to reduce the use of wheat flour in the production of food products. The objective of this investigation was to determine the effect of drying on some technological functional properties of cidra flour. The sliced cidra was dried at 40°C, 50°C, 60°C using: combined drying hot air recirculation-microwave with pulses of 4/40 seconds and drying by hot air recirculation, then obtained the flour and evaluated the techno-functional properties: index of absorption of water, capacity of retention of oil and water, capacity of swelling and capacity foaming. It was observed that the techno-functional property most affected by the drying methods was the foaming capacity, possibly due to the greater denaturation of globular proteins. The cidra flour exhibits techno-functional properties of interest for the elaboration of different food products.

Experimental Investigation on Absorption Performance of Nanofluids for CO2 Capture

Lately, absorption of carbon dioxide using nanofluids has gained more attention as this acidic gas creates global warming effect. The absorption test was conducted in a custom designed high-pressure vessel made up of stainless steel 316 L, where CO2 and nanofluid are in direct contact at static state. The type of nanoparticles and influence of its concentration on absorption of carbon dioxide are analyzed. TiO2 and Al2O3 nanofluids at 0.02–0.14[Formula: see text]wt.% concentrations are prepared by dispersing in DI water. The CO2 absorption tests were carried out for the above-mentioned nanofluids at said concentrations with operating conditions being an initial pressure of 3 bar and initial temperature of 302[Formula: see text]K. The results show that relative absorption index (RAI) of CO2 absorption has increased to a maximum and then decreased with increase in nanoparticle concentration. The aqueous-based TiO2, Al2O3 nanofluids are found to be most effective at 0.1 and 0.14[Formula: see text]wt.%, respectively, with RAI showing 39.81% and 22.3% increase in CO2 absorption as compared to basefluid, respectively. The absorption test has also been conducted for saline-based TiO2 and Al2O3 nanofluids at 1, 2, 3 and 3.1[Formula: see text]wt.% of salt concentration. The stability of saline-based nanofluids was analyzed using turbidity meter. It was found that increase in salt concentration decreases the stability of nanofluids and also decreases the CO2 absorption rate because of unstability of nanoparticles in salt solutions. Absorption decreased by 11.93% for TiO2, and 5.68% for Al2O3, when salt concentration was increased from 1 to 3.1[Formula: see text]wt.%.

Facile design of a CUT-OFF laser power attenuation using safranin O-doped PMMA polymeric composite films: Optical spectroscopy and dielectric properties

Polymethyl methacrylate with Safranin O dye samples has been prepared using the several-weight percentage of the dye varying from 0.185 to 7.407 wt % of Safranin O. We have examined their structure, optical, dielectric and optical limiting properties. The preparation has been done utilizing a fast and simple method, casting technique, where both the polymer and the dye were solved in chloroform. The characterization of the structure has been achieved using XRD where the polymeric composites samples displayed a noncrystalline hump that supports the amorphous structure of the studied films. Spectroscopy measurements have been exhausted to approximate the spectral absorption estimations of the samples like absorbance, transmittance as well as the calculations of the index of absorption (k), and optical transition bandgap (Eg). The results indicate that the optical parameters alter by increasing the concentrations of the doping dye. From the obtained values of Eg, two optical transitions (direct and indirect) are possible for these composites. According to the applied models in the polymeric materials field, dielectric characterizations have been done and their parameters have been measured. We have studied the optical limiting characteristics of the samples with several concentrations of the dye using different laser sources of He–Ne working at 632.8 nm and 533 nm. The result showed an evident optical limiting impact on the films. Utilizing this optical limiting impact, the samples under consideration are appropriate to be applied in the applications of solar cell and CUT-OFF laser filters and laser power attenuation.

Comfort optimization of a new type of foot mechanism for lower extremity exoskeleton

In order to reduce the impact caused by the contact between the foot and the ground when wearing the lower extremity exoskeleton under the condition of high load, this paper proposed an exoskeleton foot mechanism for improving the foot comfort, and optimized the key index of its influence on the comfort. Firstly, the physical model of foot mechanism was established based on the characteristics of foot stress in gait period, and then the mathematical model of vibration was abstracted. The correctness of the model was verified by the finite element analysis software ANSYS. Then, this paper analyzed the influence of vibration parameters on absolute transmissibility based on vibration mathematical model, and optimized vibration parameters with MATLAB genetic algorithm toolbox. Finally, this paper took white noise to simulate the road elevation as the vibration input, and used the visual simulation tool Simulink in MATLAB and the vibration equation to construct the acceleration simulation model, and then calculated the vibration weighted root mean square acceleration value of the foot. The results of this study show that this foot comfort mechanism can meet the comfort indexes of vibration absorption and plantar pressure, and this paper provides a relatively complete method for the design of exoskeleton foot mechanism, which has reference significance for the design of other exoskeleton foot and ankle joint rehabilitation mechanism.

Applying the resonant-state expansion to realistic materials with frequency dispersion

The dispersive resonant-state expansion, developed for an accurate calculation of the resonant states in open optical systems with frequency dispersion, is applied here to realistic materials, such as metallic nanoparticles and semiconductor microspheres. The material permittivity is determined by fitting the measured indices of refraction and absorption with a generalized Drude-Lorentz model containing a number of poles in the complex frequency plane. Each Drude or Lorentz pole generates an infinite series of resonant states. Furthermore, for small nanoparticles, each of these poles produces a distinct surface plasmon polariton mode. The evolution of these multiple surface modes with increasing radius traces the transition from the electrostatic limit to significant retardation and radiation. Treating the optical phonon range in a semiconductor microsphere, a reststrahlen band separating the resonant states is found. Considering a small energy range around the semiconductor band gap, the transition from absorption to gain is described by inverting the Lorentz pole weight, which results in the formation of lasing resonant states. Interestingly, the series of resonant states converging towards the absorption pole from the lower frequency side reshapes for a gain pole into a clockwise loop approaching the pole from the higher frequency side, being separated from a series spanning from low to high frequencies and containing the lasing modes.

Study of rheological properties of cakedough from a mixture of wheat and amaranth flour

The paper presents the study of rheological properties of cake dough from composite mixture of wheat and amaranth flour using Mixolab, Alveolab of CHOPIN company (France). It presents the basic parameters of rheological profile of wheat flour of the first grade “Alia” (Tokmak) and composite wheat and amaranth flour, points of index: index of water absorption, index of stability to mixing, index of gluten, index of viscidity, stability of starch oramylolytic index, index of retrogradations of starch.