Average Chain Length Research Articles

A re-evaluation of the average chain length of lacustrine sedimentary n-alkanes as a paleoproxy on the Qinghai-Tibet Plateau

A re-evaluation of the average chain length of lacustrine sedimentary n-alkanes as a paleoproxy on the Qinghai-Tibet Plateau

Effects of single and dual modifications with debranching and heat-moisture treatments on physicochemical, rheological, and digestibility properties of proso millet starch

The effects of single and dual modifications with heat-moisture treatment (HMT) and enzymatic debranching on the structural, physicochemical, rheological, and in-vitro digestibility properties of proso millet starch (PMS) were comparatively studied. Amylose content increased after gelatinization and all modification treatments. Debranching and dual modification (debranching followed by HMT) decreased the average chain length and swelling power but increased the solubility of PMS. HMT did not change the average chain length and chain length distribution in native and debranched starches but decreased the swelling power and solubility of native starch. The A-type X-ray diffraction pattern of PMS was converted to the A + V type by HMT and to the B + V type by debranching and dual modification. FTIR investigation showed that the short-range molecular order of all modified starches was disrupted. The viscoelasticity and viscosity of all starch pastes decreased in the following order: PMS > HMT starch > debranched starch > dual modified starch. In-vitro starch digestibility showed that HMT increased slowly digestible starch (SDS) to 32.88 %, while debranching increased resistant starch (RS) to 77.14 %. HMT increased RS to 86.17 % in the dual modified starch. Debranching therefore predominates in the dual modification of starch compared to HMT.

A Signal‐To‐Noise‐Ratio‐Based Automated Algorithm to accelerate Kinetic Monte Carlo Convergence in Basic Polymerizations

AbstractKinetic Monte Carlo (kMC) modelling is ubiquitous to simulate the time evolution of (bio)chemical processes, specifically if populations are involved. A recurring task is the selection of the smallest control volume that leads to convergence, which means that the model outputs are accurate and sufficiently free from stochastic noise and do not significantly change upon further increasing this volume. Selecting a too high (safe) control volume leads to an excessive simulation time, while many small incremental control volume increases are inefficient. This work therefore presents an automated tool to determine the smallest control volume leading to convergence. The tool is illustrated for (intrinsic) free radical and nitroxide mediated polymerization (FRP/NMP), in which the chain length distribution (CLD) is a crucial output. The algorithm starts with a very low volume to then check if the desired (monomer) conversion can be reached, the number average chain length is accurate, and finally the signal‐to‐noise (SNR) ratio at the CLD level is below a threshold. The execution time of the algorithm is less than twice the time of running the converged simulation directly, hence, saving tremendous time in setting up a kMC simulation and facilitating benchmark studies even beyond polymer reaction engineering applications.

Trajectory of stratum corneum lipid subclasses in the first year of life and associations with atopic dermatitis: A prospective cohort study

AbstractBackgroundTrajectories of stratum corneum (SC) lipid subclasses and their associations with infant atopic dermatitis (AD) are unclear. This study aimed to quantify the trajectories of 15 SC subclasses and carbon chain lengths and their associations with AD within 12 months.MethodsIn total, 213 newborns were enrolled at birth with nonlesional skin samples collected from the inner forearm at birth, 42 days, 3, 6, and 12 months, respectively. Lesional skin samples were collected from 120 AD patients at clinic with the disease onset within the first year of life. Mass spectrometry was applied to assess relative contents of 12 ceramide (CER), three free fatty acid (FFA) subclasses, and average carbon chain length (CCL). AD incident within 1 year old was diagnosed by dermatologists according to UK criteria.ResultsSixty‐four (30.0%) cases of ADs occurred in the cohort. All SC lipid subclasses and CCLs, but EOP varied significantly during the first year. AD infants showed lower NP but higher NS, NH, AP, hydroxy FFA, and CCL of FFAs compared with nonaffected infants. After normalization by age, the differences remained and were more pronounced in lesional skin of clinical AD infants compared with non‐ADs. NS, NH, and CCL of FFAs in lesional skin of AD infants showed positive and significant correlations with the levels of transepidermal water loss at 3 month; some evidence supports a negative correlation for NP.ConclusionsWe provide an overview of developmental trajectories of 15 CER and FFA subclasses across the first year of healthy infants and a link between the imbalance of some subclasses with the development of AD.

Effects of exogenous salicylic acid on starch physicochemical properties and in vitro digestion under heat stress during the grain-filling stage in waxy maize

Waxy maize starch serves as a pivotal component in global food processing and industrial applications, while high temperature (HT) during the grain-filling stage seriously affects its quality. Salicylic acid (SA) has been recognized for its role in enhancing plant heat resistance. Nonetheless, its regulatory effect on the quality of waxy maize starch under HT conditions remains unclear. In this study, two waxy maize varieties, JKN2000 (heat-tolerant) and SYN5 (heat-sensitive) were treated with SA after pollination and then subjected to HT during the grain-filling stage to explore the effect of SA on grain yield and starch quality. The results indicate that exogenous SA under HT treatment led to an increase in kernel weight and starch content in both varieties. Moreover, SA reduced the HT-induced holes on the surfaces of starch granules, enlarged the starch granule size, elevated the amylopectin branching degree, and reduced amylopectin average chain length. Consequently, improvements of pasting viscosity and the decrease of retrogradation percentage of starch were observed with SA under HT. Exogenous SA reduced HT-induced rapidly digestible starch content in SYN5, but had no significant effect on that in JKN2000. In summary, SA pretreatment effectively alleviated the detrimental effects of HT on starch pasting and thermal properties of waxy maize.

Effect of different hydrolysis methods on composition and functional properties of fish protein hydrolysate obtained from Bigeye tuna waste

SummaryThe objective of this research is to investigate the impact of different hydrolysis (chemical, enzymatic and microbiological) methods of Bigeye tuna waste (Thunnus obesus) on yield, degree of hydrolysis (DH), chemical composition, amino acid profile, functional properties and microbial quality of FPH produced. The enzymatic technique produced the highest yield (11.04%) and the greatest DH (39.04%) while it gave the lowest average peptide chain length (2.56) (P < 0.05). Also, protein and fat (76.37% and 10.82%, respectively) were the highest in the enzymatic hydrolyzed fish (FPH‐E) followed by microbial fermentation (FPH‐M) (P < 0.05). In FPH‐E, FPH‐M and chemical fish protein hydrolysates (FPH‐C), the essential to non‐essential amino acid ratios were 2.43, 1.79 and 0.51, respectively. They also had good functional properties, although they were less than FPH‐C in terms of water binding capacity (3.47 and 4.18 g g−1), oil binding capacity (9.84 and 7.38 g g−1) and foaming capacity (25% and 30%, respectively), and their foam stability rate was high. All FPHs products had a low range of microbial counts, with the FPH‐M exhibiting the greatest total count of bacteria, lactic acid bacteria and moulds and yeasts. Therefore, the biologically extracted FPH especially FPH‐E has the best compositions and qualities, making them an alternative ingredient for fish meal in fish feed formulation.

Synthesis and modification of alternative copolymers for activating membrane enzymes in vitro

Poly(styrene-co-maleic acid) (SMA) is increasingly being used for the solubilization of lipid membranes and membrane proteins is becoming more widespread. To this end, a deeper understanding of the chemical properties of the copolymer and how these translate into membrane solubilization properties and improvement of enzyme activity or stability to better promote the in vitro reaction of membrane enzymes. SMA comes in several different flavors that include the ratio of styrene to maleic acid, the distribution of comonomer sequences, the average chain length, dispersity, and potential chemical modifications. We have introduced a group of SMAs whose composition and length are well defined in a stepwise manner, and obtained the polymer (4-Cl-SMA-QA) for (-)-trans-isopiperitenone dehydrogenase (IPDH) with a single-pass membrane structure domain. The protein extraction efficiency of 4-Cl-SMA-QA is higher than that of the widely used commercial SMA(2/1), up to 82%, the kcat of IPDH embedded in 4-Cl-SMA-QA is increased by a factor of 4, a 30% decrease in Km, and a 5-fold increase in overall catalytic performance. The requirements of SMA lipid particles’ size for single-span and multi-span membrane proteins are analyzed, which is helpful for rapidly selecting suitable scaffold polymers from massive polymer libraries.

Coupled matrix-based Monte Carlo modeling for a mechanistic understanding of poly (methyl methacrylate) thermochemical recycling kinetics

Coupled matrix-based Monte Carlo (CMMC) modeling is applied to gain a deeper understanding of the mechanism underlying the thermochemical degradation of poly(methyl methacrylate) (PMMA). We take into account six elementary fission reaction types, five elementary β-scission reaction types, as well as termination by recombination and disproportionation. Additionally, we consider the influence of chain length-dependent diffusional limitations. To tune the Arrhenius parameters of the elementary reactions with enhanced sensitivity, we perform thermogravimetric analysis (TGA) with (i) well-defined heating rates (2, 4, and 8 K.min−1) and (ii) starting from well-defined PMMA feedstocks (different average chain lengths and defect levels), as pinpointed from CMMC modeling of their synthesis. Our results reveal that head-head fission plays a crucial role at lower temperatures, while a complex interplay of various elementary reactions initiated through various fission reactions occurs at higher temperatures. The CMMC model provides insights to optimize lab scale degradation reaction conditions for efficient PMMA unzipping, considering a general temperature profile. Furthermore, the model enables us to track the evolution of the molar mass distribution, particularly the contribution of heavier components.

Synergistic effect of enzymatic pre-treatment and amylose–lipid complex construction on the physicochemical properties of maize starch

In this study, the effects of maltogenic amylase (MAA) pre-treatment and starch–fatty acid complex construction on the physicochemical properties of maize starch (MAS) were investigated. The average chain length of MAA-modified MAS was found to decrease from 18.15 to 14.92. Moreover, MAA pre-treatment of starch induced the formation of a V-type complex. This behaviour was demonstrated by the higher diffraction intensity, enzymatic resistance and short-range ordering of the samples pre-treated with MAA compared with unmodified samples. X-ray diffraction and rheological analysis revealed that the re-crystallisation peak intensities and storage modulus of MAA–MAS–lauric acid (LA)/stearic acid (SA) complexes were lower than those of MAA–starches, MAS–LA/SA complexes and control. The rate of starch re-crystallisation was effectively decreased by the combination of MAA pre-treatment and V-type complex construction. The anti-retrogradation (long-term) characteristics of the tested samples were in the following order: MAA–MAS–LA/SA complexes > MAA–starches > MAS–LA/SA complexes > control.

Effects of starch multiscale structure on the physicochemical properties and digestibility of Radix Cynanchi bungei starch

Radix Cynanchi bungei (RCb) contains 40–70 % starch, yet little is known about the structure and properties of RCb starch. In this study, the multiscale structure of two cultivars of RCb starch (YW201501 and BW201001) were characterized, and the effects of starch structure on its physicochemical properties were investigated. The differences in physicochemical properties of RCb starch were influenced by its multiscale structure. The starch granules were round and irregular polygon, with sizes ranging between 2 and 14 μm. YW201501 had a higher amylose (21.81 %) and lipid (0.96 %) content, molecular weight (59.5 × 106 g/mol), and A chain proportion (27.5 %), and a lower average granule size (6.14 μm), amylopectin average chain length (19.7), and B3 chain proportion (10.3 %). Both starches were B-type crystalline, with higher crystallinity (26.3 %) and R1047/1022 (0.74) for YW201501, resulting in large gelatinization enthalpy. In addition, the higher peak viscosity and larger retrogradation degree of YW201501 were correlated to its higher amylose content. In vitro digestibility revealed that the low rapidly digestible starch and high resistant starch of BW201001 were related to the fine structure of starch. YW201501 and BW201001 had a medium glycemic index (62.6–66.0) with potential for processing into healthy starchy foods.

Enhancing Kerosene Selectivity of Fischer-Tropsch Synthesis by Periodical Pore Drainage Via Hydrogenolysis

Accumulation of wax inside the catalyst pores during transient cobalt-catalyzed Fischer-Tropsch synthesis (FTS) leads to unfavorable product distribution and low activity by imposing internal mass transfer limitations. The condensation of paraffin severely changes the apparent product stream that actually leaves the reactor before the catalyst pores are filled completely and the steady state is reached. Thus, the product distribution of the transient FTS is less complex than expected in comparison to the steady-state FTS and increasingly consists of hydrocarbons (HCs) with an average chain length in the range of kerosene (C<sub>9</sub>-C<sub>17</sub>). So, in order to prevent FTS from reaching a steady state, the pores are drained periodically by hydrogenolysis (HGL). The alternating HGL is realized by a switch from syngas (H<sub>2</sub>, CO) to pure hydrogen at a reaction temperature in the range of 210°C to 240°C. The alternating process leads to an improvement in kerosene selectivity of 48%, 37%, and 28% at 210°C, 220°C and 240°C, respectively. Furthermore, the influence of temperature on the hydrogenolysis of long-chain HCs was experimentally investigated. It was found that temperature affects methane selectivity severely. A high hydrogenolysis temperature is favorable as this leads to a severely decreased overall methane selectivity and, thus to a higher production rate of alkanes within the carbon number range of 9 to 17.

Secure and Efficient Stigmergy-Empowered Blockchain Framework for Heterogeneous Collaborative Services in the Internet of Vehicles

The Internet of Vehicles (IoV) is expected to address the significant problems of modern transportation through collaboration among various entities. It is crucial to establish a collaborative mechanism for untrusted entities to achieve the full potential of IoV. Blockchain is a promising solution for building a credible environment for entities. However, because of the difference and complexity of services, using a classical blockchain system to support heterogeneous collaborative services in IoV causes some challenges in smart contract support, system security, and computational efficiency. In this article, we propose a stigmergy-empowered blockchain framework called SEB, which enables untrusted IoV entities to perform heterogeneous collaborative services conveniently, securely, and efficiently. Specifically, we first explore the characteristics of collaborative services and analyze the challenges of existing blockchain systems. Furthermore, we introduce the stigmergy of swarm intelligence into blockchain and integrate the stigmergy into SEB by designing a new transaction data structure, a digital pheromone and transaction selection rules, and a new transaction selection algorithm. Simulation experiments demonstrate that compared with IOTA, SEB reduces smart contract transaction sorting searches by approximately 56%, increases the average chain length by up to approximately 87%, and decreases the computation time of the transaction selection algorithm by up to approximately 98%.

Habitat area and edges affect the length of trophic chains in a fragmented forest.

The food chain length represents how much energy reaches different trophic levels in food webs. Environmental changes derived from human activities have the potential to affect chain length. We explore how habitat area and edges affect chain length through: (1) a bottom-up effect of abundance ('pyramid hypothesis'); (2) the truncation of the highest trophic level ('trophic-rank hypothesis'); and (3) changes in species connectivity patterns ('connectivity hypothesis'). We built plant-leaf miner-parasitoid food webs in 19 remnants of a fragmented Chaco forest from central Argentina. On each remnant, we constructed food webs from different locations at the forest interior and edges. For each food web, we registered the abundance of species, the species richness of each trophic level, estimated the connectivity of their networks, and the average food chain length. We used structural equation models to evaluate the direct and indirect effects of habitat area and edge/interior location on food chain length mediated by species richness, abundance and connectivity. We found no direct effects of habitat area on chain length but chains were longer at forest edges than at their interior. The three mechanisms were supported by our results, although they showed different strengths. First, we found that the interior favours a bottom-up abundance effect from herbivores to parasitoids that positively affected chain length; second, we found that the forest area positively affects plant richness, which has a strong effect on the number of resources used by consumers, with a positive effect on chain length. Third, the remnant area and interior position favoured plant richness with a negative effect on the abundance of parasitoids, which had a positive effect on chain length. In general, the strongest effects on chain length were detected through changes in abundance rather than species richness although abundance was less affected by habitat fragmentation. We evaluated for the first time the effects of human-driven habitat fragmentation on the length of trophic chains in highly diverse plant-herbivore-parasitoid networks. Despite the loss of species, small habitat fragments and edges embedded in the agricultural matrix can support interaction networks, making them conservation targets in managed landscapes.

Calanus finmarchicus as a novel source of health-promoting bioactive peptides: Enzymatic protein hydrolysis, characterization, and in vitro bioactivity

Calanus finmarchicus is a crustacean currently used as a source of marine lipid. The lipids are extracted by enzymatic protein hydrolysis, while the remaining peptide fraction is regarded as a byproduct. In the present work, ten different commercial proteases and endogenous C. finmarchicus proteases were used to produce a set of 63 protein hydrolysates. Protease concentration and hydrolysis time were varied. Hydrolysates were characterized using size-exclusion chromatography and 1H nuclear magnetic resonance spectroscopy. Addition of commercial proteases had unremarkable effect on the yield and molecular weight distribution. This was attributed to the strong impact of endogenous enzymes dominating the hydrolysis process. However, multivariate classification based on 1H NMR spectra revealed subtle variations in composition of hydrolysates produced using different enzymes. The hydrolysates were further evaluated for DPP-IV inhibition and antioxidant activity. The hydrolysates showed significantly higher bioactivity than the unhydrolyzed control. A representative hydrolysate (CaFi55) was fractionated using semipreparative size-exclusion chromatography. A fraction consisting of short peptides with an average chain length of five amino acids (F2), was identified as a major contributor to the DPP-IV inhibitory activity (IC50 = 0.70 ± 0.07 mg/mL).

Synergistic solidification/stabilization mechanism of cadmium in phosphogypsum slag-based cementitious material

The phosphogypsum slag-based cementitious material (PS), a type of low-carbon cementitious materials, showed its potential in solidifying heavy metals. This paper is aimed to investigate the efficiency of PS in immobilising heavy metal cadmium (Cd) and explore the solidification mechanism. In the study, the PS specimens doped with different Cd(NO3)2 content (0–1.0% by weight) were prepared and the solidification efficiency was determined by leaching test. Moreover, the mechanism of solidification of Cd in PS were explored by characterising hydration behaviour of Cd-substituted PS by XRD, TGA, NMR, FTIR and SEM-EDS. The results showed that the best performance was observed in Cd mixed PS with 50% slag, 45% phosphogypsum and 5% lime, which showed a compressive strength of 37.3 MPa and a metal leaching concentration of 0.134 µg/L. The ettringite and C-S-H were observed as the main hydration products of PS system. Moreover, it was found that Cd was bound to the phases of sulfoaluminate and silicate and substituted to Ca2+ in the crystal structure or Cd(OH)2 being trapped by C-S-H, the substitution and trapping of which lead to a shortening of the average chain length of C-S-H and delay the hydration process of the Cd-doped PS system.

Genetic architecture and key regulatory genes of fatty acid composition in Gushi chicken breast muscle determined by GWAS and WGCNA

BackgroundFatty acids composition in poultry muscle is directly related to its tenderness, flavour, and juiciness, whereas its genetic mechanisms have not been elucidated. In this study, the genetic structure and key regulatory genes of the breast muscle fatty acid composition of local Chinese chicken, Gushi-Anka F2 resource population by integrating genome-wide association study (GWAS) and weighted gene co-expression network analysis (WGCNA) strategies. GWAS was performed based on 323,306 single nucleotide polymorphisms (SNPs) obtained by genotyping by sequencing (GBS) method and 721 chickens from the Gushi-Anka F2 resource population with highly variable fatty acid composition traits in the breast muscle. And then, according to the transcriptome data of the candidate genes that were obtained and phenotypic data of fatty acid composition traits in breast muscle of Gushi chickens at 14, 22, and 30 weeks of age, we conducted a WGCNA.ResultsA total of 128 suggestive significantly associated SNPs for 11 fatty acid composition traits were identified and mapped on chromosomes (Chr) 2, 3, 4, 5, 13, 17, 21, and 27. Of these, the two most significant SNPs were Chr13:5,100,140 (P = 4.56423e-10) and Chr13:5,100,173 (P = 4.56423e-10), which explained 5.6% of the phenotypic variation in polyunsaturated fatty acids (PUFA). In addition, six fatty acid composition traits, including C20:1, C22:6, saturated fatty acid (SFA), unsaturated fatty acids (UFA), PUFA, and average chain length (ACL), were located in the same QTL intervals on Chr13. We obtained 505 genes by scanning the linkage disequilibrium (LD) regions of all significant SNPs and performed a WGCNA based on the transcriptome data of the above 505 genes. Combining two strategies, 9 hub genes (ENO1, ADH1, ASAH1, ADH1C, PIK3CD, WISP1, AKT1, PANK3, and C1QTNF2) were finally identified, which could be the potential candidate genes regulating fatty acid composition traits in chicken breast muscle.ConclusionThe results of this study deepen our understanding of the genetic mechanisms underlying the regulation of fatty acid composition traits, which is helpful in the design of breeding strategies for the subsequent improvement of fatty acid composition in poultry muscle.

Starch chain-length distributions determine cooked foxtail millet texture and starch physicochemical properties

Starch chain-length distributions play an important role in controlling cereal product texture and starch physicochemical properties. Cooked foxtail millet texture and starch physicochemical properties were investigated and correlated with starch chain-length distributions in eight foxtail millet varieties. The average chain lengths of amylopectin and amylose were in the range of DP 24–25 and DP 878–1128, respectively. The percentage of short amylopectin chains (Ap1) was negatively correlated with hardness but positively correlated with adhesiveness and cohesion. Conversely, the amount of amylose intermediate chains was positively correlated with hardness but negatively correlated with adhesiveness and cohesion. Additionally, the amount of amylose long chains was negatively correlated with adhesiveness and chewiness. The relative crystallinity (RC) of starch decreased with reductions in the length of amylopectin short chains in foxtail millet. Pasting properties were mainly influenced by the relative length of amylopectin side chains and the percentage of long amylopectin branches (Ap2). Longer amylopectin long chains resulted in lower gelatinization temperature and enthalpy (ΔH). The amount of starch branched chains had important effects on the gelatinization temperature range (ΔT). These results can provide guidance for breeders and food scientists in the selection of foxtail millet with improved quality properties.

Physical and chemical changes to commercial sodium phosphate glasses after aging or dynamic vapor sorption

Commercial sodium phosphate glasses are used as reference materials for polyphosphate chain length analysis. Water can spontaneously hydrolytically degrade the characteristic polyphosphate P-O-P bond, and reduce the polyphosphate chain length. XRD, Raman spectroscopy, and SEM were used to characterize glasses stored for two weeks, six months and >10 years, and three commercial sodium phosphate glasses after controlled water vapor adsorption and desorption. Rapid water vapor absorption was measured above 50 % relative humidity. The chain length distribution for a dissolved commercial sodium phosphate glass with an average chain length of 45 PO3− units was analyzed with polyacrylamide gel electrophoresis. A distribution of linear polyphosphates, interrupted with a population spike of ∼13 PO3− units, trimetaphosphate rings, and orthophosphates were identified. 31P-MAS NMR suggested that the linear polyphosphate population spike could be the product of large ring polyphosphate scission upon dissolution. This study confirms the importance of dry storage for chain length reference phosphate glasses.

Metabolism of free fatty acids in patients with gastrointestinal diseases depending on the body mass index

Background. The purpose of the study is to analyze the content of free fatty acids (FFA) in the blood serum of overweight and underweight patients with gastrointestinal diseases. Mate­rials and methods. Thirty-one patients with gastrointestinal diseases were examined, 19 (61.3 %) men and 12 (38.7 %) women with a median age of 39 (27; 48) years. Depending on the results of the body composition study with the multifunctional monitor TANITA MC-780MA (Japan), they were divided into the following groups: overweight patients (body mass index (BMI) more than 25.0 kg/m2) and underweight persons (BMI below 18.5 kg/m2). Determination of the FFA spectrum in the blood serum was carried out using a gas chromatograph with a flame ionization detector Chromatek-Crystal 5000. The control group consisted of 16 practically healthy people. Statistical processing of the results was carried out using the Statistica 6.1 application program package. Results. Patients with a change in body weight reported a statistically significant decrease in the median total content of short-chain saturated FFA (C4:0) mainly due to a decrease in the butyric acid content by 67 times (p = 0.001) with increased BMI and by 114 times (p = 0.002) with decreased BMI compared to controls. At the same time, the analysis of the serum spectrum of saturated FFA with an average carbon chain length showed a probable increase in the content of capric acid by 14 times (p < 0.01), undecyl acid by 19 times (p < 0.01), and lauric acid by 25 times (p < 0.001) in patients with changes in body weight. The content of caproic acid increased in the group with excessive body weight by 3.9 times (p = 0.046) compared to controls and by 2.6 times (p > 0.05) compared to underweight patients. The total content of monounsaturated FFA in the blood serum of patients with increased and decreased BMI increased significantly by 32 times (p < 0.001) and 19 times (p = 0.001), respectively, compared to controls. The total content of polyunsaturated FFA in the blood serum of patients of both groups was found in a trace amount. Overweight patients had a 38-fold (p < 0.01) increase in the trans-FFA elaidic acid (C18:1(trans-9)) compared to controls, while underweight patients had a decrease in linoelaidic acid (C18:2(trans-9,12)) by 11.7 times (p < 0.05). Correlation analysis revealed a positive relationship between BMI and increased serum content of saturated caproic acid (r = 0.39; p = 0.019); monounsaturated acids — palmitoleic (r = 0.33; р = 0.045) and heptadecenoic (r = 0.35; р = 0.034); trans-configuration fatty acids — elaidic (r = 0.43; p = 0.009) and linoelaidic (r = 0.43; p = 0.007). Conclusions. Patients with gastrointestinal diseases had an imbalance in the fatty acid spectrum of the blood serum. Against the background of the tendency to decrease the total content of short-chain saturated FFA, a significant increase in the content of monounsaturated FFA and trans-FFA was noted, especially with increased BMI. In all patients, the trace amount of polyunsaturated FFA fractions was found. The obtained results can be used to improve the differential treatment of metabolic disorders in patients with gastrointestinal tract pathology.

BaO–reinforced SiO2–Na2O–Ca(O/F2)–Al2O3 glasses for radiation safety: On the physical, optical, structural and radiation shielding properties

This paper reports on a study aimed at investigating the physical properties and radiation shielding capability of a low-cost, high-transparency silicate glassy system reinforced with barium oxide. The prepared glasses' elementary and modified network structures were analyzed using X-ray diffraction and Raman spectroscopy, confirming their glass nature and revealing the progressive network depolymerization with BaO inclusion. Differential scanning calorimetry was employed to determine the glass transition temperature, which showed an increase with increasing BaO content. Tauc's plot was used to study the direct optical bandgap, which was observed to increase from 3.91 to 4.75 eV with BaO content from 0 to 30 mol%, linked to an increase in the average oxygen bond chain length and non-bridging oxygen atoms' creation. The density, molar volume, and oxygen packing density of the glass were found to increase with BaO addition, indicating that barium oxide promotes the formation of a compact network structure collapsing into a closely packed arrangement. At an X-ray energy of 40 keV, the mass attenuation coefficient increased from 0.67 to 11.48 cm2/g with BaO content. To assess the efficacy of theoretical calculations, we have conducted an experimental setup to measure the linear attenuation coefficient using an 241Am (59.5 keV) radiation source. Finally, the gamma shielding effectiveness was evaluated, and the sample containing 30 mol% of BaO showed superior radiation protection compared to concrete and was comparable to RS360 commercial glass.