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In the current work, nanocrystalline powders with different compositions, namely Li0.98Pr0.02NbO3, Li0.93Pr0.02Mg0.05NbO3 and Li0.98Pr0.02TaO3 were synthesized for the first time using the method of high-energy ball milling of the starting materials (Li2CO3, Nb2O5, Ta2O5, MgO, Pr6O11), followed by high-temperature annealing. XRD data analysis confirmed the absence of parasitic phases in the obtained nanocrystalline compounds. The estimated particle sizes ranged from 20 to 80 nm. From the obtained nanopowders, ceramic samples were prepared using specially developed equipment, which allowed for pressing at elevated temperatures with a simultaneous application of a constant electric field. The obtained photoluminescence spectra exhibit characteristic features of Pr3+ ions in the crystal structure of LiNbO3 and LiTaO3 and are most efficiently excited by UV light. Samples pressed with an electric field application show higher intensity of photoluminescence. Investigations of the temperature dependence of electrical conductivity of the Li0.98Pr0.02NbO3 sample, pressed with the application of an electric field, indicate that the conductivity mechanism is similar to that of LiNbO3 single crystals and, at high temperatures, is attributed to the lithium conduction mechanism.

Stilbenes in the roots of Carex acuta and Carex lepidocarpa were studied. Root samples were extracted with 100% methanol and analyzed by HPLC and LC-MS. In this way, trans-resveratrol dimers (m/z 455 Da [M + H]+), trimers (m/z 681 Da [M + H]+) and tetramers (m/z 907 Da [M + H]+) were identified in the extracts. Using LC-NMR in stop-flow mode, pallidol and trans-ε-viniferin as dimers were identified. After the separation of individual peaks and their measurement by 1H NMR, cis and trans-miyabenol A as a tetramer and cis-miyabenol C as a trimer were identified. In the case of miyabenol A, it is a chromatographically inseparable mixture of cis and trans isomers in the ratio of 2:3 according to 1H NMR measurement. In the case of cis-miyabenol C, the Z-trans-trans-miyabenol C configuration was confirmed. The remaining unidentified peak with a practically identical UV-VIS spectrum to that of cis-miyabenol C is most likely another isomer of miyabenol C.

This paper introduces the Botox Optimization Algorithm (BOA), a novel metaheuristic inspired by the Botox operation mechanism. The algorithm is designed to address optimization problems, utilizing a human-based approach. Taking cues from Botox procedures, where defects are targeted and treated to enhance beauty, the BOA is formulated and mathematically modeled. Evaluation on the CEC 2017 test suite showcases the BOA’s ability to balance exploration and exploitation, delivering competitive solutions. Comparative analysis against twelve well-known metaheuristic algorithms demonstrates the BOA’s superior performance across various benchmark functions, with statistically significant advantages. Moreover, application to constrained optimization problems from the CEC 2011 test suite highlights the BOA’s effectiveness in real-world optimization tasks.

This research paper develops a novel hybrid approach, called hybrid particle swarm optimization–teaching–learning-based optimization (hPSO-TLBO), by combining two metaheuristic algorithms to solve optimization problems. The main idea in hPSO-TLBO design is to integrate the exploitation ability of PSO with the exploration ability of TLBO. The meaning of “exploitation capabilities of PSO” is the ability of PSO to manage local search with the aim of obtaining possible better solutions near the obtained solutions and promising areas of the problem-solving space. Also, “exploration abilities of TLBO” means the ability of TLBO to manage the global search with the aim of preventing the algorithm from getting stuck in inappropriate local optima. hPSO-TLBO design methodology is such that in the first step, the teacher phase in TLBO is combined with the speed equation in PSO. Then, in the second step, the learning phase of TLBO is improved based on each student learning from a selected better student that has a better value for the objective function against the corresponding student. The algorithm is presented in detail, accompanied by a comprehensive mathematical model. A group of benchmarks is used to evaluate the effectiveness of hPSO-TLBO, covering various types such as unimodal, high-dimensional multimodal, and fixed-dimensional multimodal. In addition, CEC 2017 benchmark problems are also utilized for evaluation purposes. The optimization results clearly demonstrate that hPSO-TLBO performs remarkably well in addressing the benchmark functions. It exhibits a remarkable ability to explore and exploit the search space while maintaining a balanced approach throughout the optimization process. Furthermore, a comparative analysis is conducted to evaluate the performance of hPSO-TLBO against twelve widely recognized metaheuristic algorithms. The evaluation of the experimental findings illustrates that hPSO-TLBO consistently outperforms the competing algorithms across various benchmark functions, showcasing its superior performance. The successful deployment of hPSO-TLBO in addressing four engineering challenges highlights its effectiveness in tackling real-world applications.

Sorghum is one of the most important foods, fodder, and technical crops grown in the world. Global climate change and environmental pollution with toxic industrial and agricultural waste are the most unfavorable environmental factors affecting the growth and development of sorghum, which leads to a decrease in product quality. The development of new environmentally friendly plant growth regulators to improve growth and increase the productivity of sorghum is an urgent task of modern agriculture. Currently, considerable attention is paid to the development of new environmentally friendly plant growth regulators based on 6-methyl-2-mercapto-4-hydroxypyrimidine sodium and potassium salts (Methyur and Kamethur) and N-oxide-2,6-dimethylpyridine (Ivin). Thanks to the use of plant growth regulators Methyur, Kamethur, and Ivin, it is possible to increase the productivity of agricultural crops and their adaptive properties to stress factors of abiotic nature. This work examines the use of plant growth regulators Methyur, Kamethur, and Ivin to increase the productivity of sorghum. Field experiments were carried out on grain sorghum (Sorghum bicolor L.) cv. Yarona and sweet sorghum (Sorghum saccharatum L.) cv. Favorite. Seeds sterilized with 1% KMnO4 solution were treated either with distilled water (control sample) or with solutions of any plant growth regulators Methyur, Kamethur, or Ivin, applied at a concentration of 10−7 M for 24 h (experimental sample). Each control and experimental sample contained 50 plant seeds; the experiments were carried out in triplicate. Then the soaked seeds were planted in the soil. Yield indicators such as panicle length (in cm) and fresh weight of grain (in grams), determined in experimental samples of sorghum plants, were calculated as % in relation to similar indicators determined in control samples of sorghum plants. It was shown that the yield indicators of sorghum plants grown for 4 months in the field, treated with Methyur, Kamethur, and Ivin at a concentration of 10−7 M exceeded those of control plants. Panicle length (in %) of experimental grain sorghum (Sorghum bicolor (L.) Moench) cv. Yarona increased by 7%—in plants treated with Kamethur, 20%—in plants treated with Methyur, and 17%—in plants treated with Ivin, compared to the control. Panicle length (in %) of experimental sweet sorghum (Sorghum saccharatum (L.) Moench) cv. Favorite increased by 36%—in plants treated with Kamethur, 37%—in plants treated with Methyur, and by 25%—in plants treated with Ivin, compared to the control. Grain fresh weight (in %) of experimental grain sorghum (Sorghum bicolor (L.) Moench) cv. Yarona increased by 22%—in plants treated with Kamethur, 26%—in plants treated with Methyur, and 13%—in plants treated with Ivin, compared to the control. Grain fresh weight (in %) of experimental sweet sorghum (Sorghum saccharatum (L.) Moench) cv. Favorite increased by 24%—in plants treated with Kamethur, 38%—in plants treated with Methyur, and 35%—in plants treated with Ivin, compared to the control. Based on the results obtained, a conclusion was made about the high growth-stimulating effect of plant growth regulators, similar to the phytohormones auxins and cytokinin, and the dependence of their effect on their composition. It is proposed to use new environmentally friendly plant growth regulators Methyur, Kamethur, and Ivin to improve growth and increase the productivity of sorghum while reducing the use of environmentally toxic agrochemicals for plant protection and improving the environmental condition of the entire agricultural system.

Polyploidization in plants, which involves doubling or further multiplying of genome, has the potential to improve the constituents that make medicinal plants, like Ajuga reptans, attractive to the pharmaceutical, cosmetics, and food production industries; botanical pesticide effects could also be derived. The aim of this study was to determine how artificial polyploidization in A. reptans plants affected the composition and quantity of biologically active substances from the glycoside and phytoecdysone families. Diploids and artificial tetraploids of A. reptans were analyzed. Changes in the contents of trans-teupolioside, trans-verbascoside, and 20-hydroxyecdysone were evident in the aboveground parts of the cultivated plants (e.g., leaves and flowers). The tetraploid lines of Ajuga plants displayed variability in, and increased levels of, trans-teupolioside and trans-verbascoside content. The 20-hydroxecdysone content was slightly higher in tetraploids. These findings indicated that Ajuga tetraploids could be used in breeding programs to enhance the yield of substances with potential medicinal and industrial applications.

Electric train system is a very large load for the power network. This load consumes a large amount of reactive power. In addition, it causes a massive unbalance to the network, which results in many problems such as voltage drops, high transmission losses, reduction in the transformer output ability, negative sequence current, mal-operation of protective relays, etc. In this paper, a novel real-time optimization approach is presented to adjust the static VAR compensator (SVC) for the traction system to realize two objectives; current unbalance reduction and reactive power compensation. A multi-objective optimization technique entitled non-dominated sorting genetic algorithm (NSGA-II) is used to fulfill the regarded objectives simultaneously. A comprehensive simulator has been designed for electric train network modeling that is able to adjust the parameters of SVC in an optimum manner at any time and under any circumstances. The results illustrate that the provided method can efficiently reduce the unbalancing in current as well as supply the demanded reactive power with acceptable precision.

Numerous optimization problems have been defined in different disciplines of science that must be optimized using effective techniques. Optimization algorithms are an effective and widely used method of solving optimization problems that are able to provide suitable solutions for optimization problems. In this paper, a new nature-based optimization algorithm called Snow Leopard Optimization Algorithm (SLOA) is designed that mimics the natural behaviors of snow leopards. SLOA is simulated in four phases including travel routes, hunting, reproduction, and mortality. The different phases of the proposed algorithm are described and then the mathematical modeling of the SLOA is presented in order to implement it on different optimization problems. A standard set of objective functions, including twenty-three functions, is used to evaluate the ability of the proposed algorithm to optimize and provide appropriate solutions for optimization problems. Also, the optimization results obtained from the proposed SLOA are compared with eight other well-known optimization algorithms. The optimization results show that the proposed SLOA has a high ability to solve various optimization problems. Also, the analysis and comparison of the optimization results obtained from the SLOA with the other eight algorithms shows that the SLOA is able to provide more appropriate quasi-optimal solutions and closer to the global optimal, and with better performance, it is much more competitive than similar algorithms.

The research presented in this manuscript proposes a novel Harris Hawks optimization algorithm with practical application for evolving convolutional neural network architecture to classify various grades of brain tumor using magnetic resonance imaging. The proposed improved Harris Hawks optimization method, which belongs to the group of swarm intelligence metaheuristics, further improves the exploration and exploitation abilities of the basic algorithm by incorporating a chaotic population initialization and local search, along with a replacement strategy based on the quasi-reflection-based learning procedure. The proposed method was first evaluated on 10 recent CEC2019 benchmarks and the achieved results are compared with the ones generated by the basic algorithm, as well as with results of other state-of-the-art approaches that were tested under the same experimental conditions. In subsequent empirical research, the proposed method was adapted and applied for a practical challenge of convolutional neural network design. The evolved network structures were validated against two datasets that contain images of a healthy brain and brain with tumors. The first dataset comprises well-known IXI and cancer imagining archive images, while the second dataset consists of axial T1-weighted brain tumor images, as proposed in one recently published study in the Q1 journal. After performing data augmentation, the first dataset encompasses 8.000 healthy and 8.000 brain tumor images with grades I, II, III, and IV and the second dataset includes 4.908 images with Glioma, Meningioma, and Pituitary, with 1.636 images belonging to each tumor class. The swarm intelligence-driven convolutional neural network approach was evaluated and compared to other, similar methods and achieved a superior performance. The obtained accuracy was over 95% in all conducted experiments. Based on the established results, it is reasonable to conclude that the proposed approach could be used to develop networks that can assist doctors in diagnostics and help in the early detection of brain tumors.

In this study, the effects of occupational exposure to nanoparticles (NPs) were studied by NMR metabolomics. Exhaled breath condensate (EBC) and blood plasma samples were obtained from a research nanoparticles-processing unit at a national research university. The samples were taken from three groups of subjects: samples from workers exposed to nanoparticles collected before and after shift, and from controls not exposed to NPs. Altogether, 60 1H NMR spectra of exhaled breath condensate (EBC) samples and 60 1H NMR spectra of blood plasma samples were analysed, 20 in each group. The metabolites identified together with binning data were subjected to multivariate statistical analysis, which provided clear discrimination of the groups studied. Statistically significant metabolites responsible for group separation served as a foundation for analysis of impaired metabolic pathways. It was found that the acute effect of NPs exposure is mainly reflected in the pathways related to the production of antioxidants and other protective species, while the chronic effect is manifested mainly in the alteration of glutamine and glutamate metabolism, and the purine metabolism pathway.

Numerous optimization problems designed in different branches of science and the real world must be solved using appropriate techniques. Population-based optimization algorithms are some of the most important and practical techniques for solving optimization problems. In this paper, a new optimization algorithm called the Cat and Mouse-Based Optimizer (CMBO) is presented that mimics the natural behavior between cats and mice. In the proposed CMBO, the movement of cats towards mice as well as the escape of mice towards havens is simulated. Mathematical modeling and formulation of the proposed CMBO for implementation on optimization problems are presented. The performance of the CMBO is evaluated on a standard set of objective functions of three different types including unimodal, high-dimensional multimodal, and fixed-dimensional multimodal. The results of optimization of objective functions show that the proposed CMBO has a good ability to solve various optimization problems. Moreover, the optimization results obtained from the CMBO are compared with the performance of nine other well-known algorithms including Genetic Algorithm (GA), Particle Swarm Optimization (PSO), Gravitational Search Algorithm (GSA), Teaching-Learning-Based Optimization (TLBO), Grey Wolf Optimizer (GWO), Whale Optimization Algorithm (WOA), Marine Predators Algorithm (MPA), Tunicate Swarm Algorithm (TSA), and Teamwork Optimization Algorithm (TOA). The performance analysis of the proposed CMBO against the compared algorithms shows that CMBO is much more competitive than other algorithms by providing more suitable quasi-optimal solutions that are closer to the global optimal.

Nanocrystalline compounds LiNb1−xTaxO3 of various compositions (x = 0, 0.25, 0.5, 0.75, 1) were synthesized by high-energy ball milling of the initial materials (Li2CO3, Nb2O5, Ta2O5) and subsequent high-temperature annealing of the resulting powders. Data on the phase composition of the nanopowders were obtained by X-ray diffraction methods, and the dependence of the structural parameters of LiNb1−xTaxO3 compounds on the value of x was established. As a result of the experiments, the optimal parameters of the milling and annealing runs were determined, which made it possible to obtain single-phase compounds. The Raman scattering spectra of LiNb1−xTaxO3 compounds (x = 0, 0.25, 0.5, 0.75, 1) have been investigated. Preliminary experiments have been carried out to study the temperature dependences of their electrical conductivity.

There are many optimization problems in the different disciplines of science that must be solved using the appropriate method. Population-based optimization algorithms are one of the most efficient ways to solve various optimization problems. Population-based optimization algorithms are able to provide appropriate solutions to optimization problems based on a random search of the problem-solving space without the need for gradient and derivative information. In this paper, a new optimization algorithm called the Group Mean-Based Optimizer (GMBO) is presented; it can be applied to solve optimization problems in various fields of science. The main idea in designing the GMBO is to use more effectively the information of different members of the algorithm population based on two selected groups, with the titles of the good group and the bad group. Two new composite members are obtained by averaging each of these groups, which are used to update the population members. The various stages of the GMBO are described and mathematically modeled with the aim of being used to solve optimization problems. The performance of the GMBO in providing a suitable quasi-optimal solution on a set of 23 standard objective functions of different types of unimodal, high-dimensional multimodal, and fixed-dimensional multimodal is evaluated. In addition, the optimization results obtained from the proposed GMBO were compared with eight other widely used optimization algorithms, including the Marine Predators Algorithm (MPA), the Tunicate Swarm Algorithm (TSA), the Whale Optimization Algorithm (WOA), the Grey Wolf Optimizer (GWO), Teaching–Learning-Based Optimization (TLBO), the Gravitational Search Algorithm (GSA), Particle Swarm Optimization (PSO), and the Genetic Algorithm (GA). The optimization results indicated the acceptable performance of the proposed GMBO, and, based on the analysis and comparison of the results, it was determined that the GMBO is superior and much more competitive than the other eight algorithms.

Discrete mathematics covers the field of graph theory, which solves various problems in graphs using algorithms, such as coloring graphs. Part of graph theory is focused on algorithms that solve the passage through mazes and labyrinths. This paper presents a study conducted as part of a university course focused on graph theory. The course addressed the problem of high student failure in the mazes and labyrinths chapter. Students’ theoretical knowledge and practical skills in solving algorithms in the maze were low. Therefore, the use of educational robots and their involvement in the teaching of subjects in part focused on mazes and labyrinths. This study shows an easy passage through the individual areas of teaching the science, technology, engineering, and mathematics (STEM) concept. In this article, we describe the research survey and focus on the description and examples of teaching in a university course. Part of the work is the introduction of an easy transition from the theoretical solution of algorithms to their practical implementation on a real autonomous robot. The theoretical part of the course introduced the issues of graph theory and basic algorithms for solving the passage through the labyrinth. The contribution of this study is a change in the approach to teaching graph theory and a greater interconnection of individual areas of STEM to achieve better learning outcomes for science students.

Engineered small non-antibody protein scaffolds are a promising alternative to antibodies and are especially attractive for use in protein therapeutics and diagnostics. The advantages include smaller size and a more robust, single-domain structural framework with a defined binding surface amenable to mutation. This calls for a more systematic approach in designing new scaffolds suitable for use in one or more methods of directed evolution. We hereby describe a process based on an analysis of protein structures from the Protein Data Bank and their experimental examination. The candidate protein scaffolds were subjected to a thorough screening including computational evaluation of the mutability, and experimental determination of their expression yield in E. coli, solubility, and thermostability. In the next step, we examined several variants of the candidate scaffolds including their wild types and alanine mutants. We proved the applicability of this systematic procedure by selecting a monomeric single-domain human protein with a fold different from previously known scaffolds. The newly developed scaffold, called ProBi (Protein Binder), contains two independently mutable surface patches. We demonstrated its functionality by training it as a binder against human interleukin-10, a medically important cytokine. The procedure yielded scaffold-related variants with nanomolar affinity.

Let (Fn)n≥0 be the Fibonacci sequence given by Fn+2=Fn+1+Fn, for n≥0, where F0=0 and F1=1. There are several interesting identities involving this sequence such as Fn2+Fn+12=F2n+1, for all n≥0. In 2012, Chaves, Marques and Togbé proved that if (Gm)m is a linear recurrence sequence (under weak assumptions) and Gn+1s+⋯+Gn+ℓs∈(Gm)m, for infinitely many positive integers n, then s is bounded by an effectively computable constant depending only on ł and the parameters of (Gm)m. In this paper, we shall prove that if P(x1,…,xℓ) is an integer homogeneous s-degree polynomial (under weak hypotheses) and if P(Gn+1,…,Gn+ℓ)∈(Gm)m for infinitely many positive integers n, then s is bounded by an effectively computable constant depending only on ℓ, the parameters of (Gm)m and the coefficients of P.

Let α≠1 be a positive real number and let P(x) be a non-constant rational function with algebraic coefficients. In this paper, in particular, we prove that the set of algebraic numbers of the form αP(T), with T transcendental, is dense in some open interval of R.

Let Fn be the nth Fibonacci number. The order of appearance z(n) of a natural number n is defined as the smallest positive integer k such that Fk≡0(modn). In this paper, we shall find all positive solutions of the Diophantine equation z(φ(n))=n, where φ is the Euler totient function.

Let k ≥ 1 be an integer and denote ( F k , n ) n as the k-Fibonacci sequence whose terms satisfy the recurrence relation F k , n = k F k , n − 1 + F k , n − 2 , with initial conditions F k , 0 = 0 and F k , 1 = 1 . In the same way, the k-Lucas sequence ( L k , n ) n is defined by satisfying the same recursive relation with initial values L k , 0 = 2 and L k , 1 = k . The sequences ( F k , n ) n ≥ 0 and ( L k , n ) n ≥ 0 were introduced by Falcon and Plaza, who derived many of their properties. In particular, they proved that F k , n 2 + F k , n + 1 2 = F k , 2 n + 1 and F k , n + 1 2 − F k , n − 1 2 = k F k , 2 n , for all k ≥ 1 and n ≥ 0 . In this paper, we shall prove that if k > 1 and F k , n s + F k , n + 1 s ∈ ( F k , m ) m ≥ 1 for infinitely many positive integers n, then s = 2 . Similarly, that if F k , n + 1 s − F k , n − 1 s ∈ ( k F k , m ) m ≥ 1 holds for infinitely many positive integers n, then s = 1 or s = 2 . This generalizes a Marques and Togbé result related to the case k = 1 . Furthermore, we shall solve the Diophantine equations F k , n = L k , m , F k , n = F n , k and L k , n = L n , k .

Grape cane, leaves and grape marc are waste products from viticulture, which can be used to obtain secondary stilbene derivatives with high antioxidant value. The presented work compares several extraction methods: maceration at laboratory temperature, extraction at elevated temperature, fluidized-bed extraction, Soxhlet extraction, microwave-assisted extraction, and accelerated solvent extraction. To obtain trans-resveratrol, trans-ε-viniferin and r2-viniferin from grape cane of the V. vinifera variety Cabernet Moravia, various conditions were studied: different solvents, using powdered versus cut cane material, different extraction times, and one-step or multiple extractions. The largest concentrations found were 6030 ± 680 µg/g dry weight (d.w.) for trans-resveratrol, 2260 ± 90 µg/g d.w. for trans-ε-viniferin, and 510 ± 40 µg/g d.w. for r2-viniferin. The highest amounts of stilbenes (8500 ± 1100 µg/g d.w.) were obtained using accelerated solvent extraction in methanol.

Changes in surface material characteristics can significantly affect the adhesion and overall life of coatings on wood. In order to increase the durability of transparent exterior coatings, it is possible to use the surface modification of wood with UV-stabilizing substances. In this work, selected types of surface modifications using benzotriazoles, HALS, ZnO and TiO2 nanoparticles, and their combinations were applied to oak wood (Quercus robur, L.). On such modified surfaces, the surface free energy, roughness, and contact wetting angle with three selected types of exterior transparent coatings were subsequently determined. An oil-based coating, waterborne acrylic thick layer coating, and thin-layer synthetic coating were tested and interaction with the aforementioned surface modifications was investigated after 6 weeks of accelerated artificial weathering. The results of changes in the initially measured surface characteristics of the modified oak wood were compared to the real results of degradation of coatings after artificial accelerated weathering. The positive effect of surface modification, in particular the mixture of benzotriazoles, HALS, and ZnO nanoparticles on all kinds of coatings was proven, and the best results were observed in thick-film waterborne acrylic coating. The changes in the measured surface characteristics corresponded to the observed durability of the coatings only when measured by wetting using drops of the tested coatings.

This paper deals with the development and characteristics of the properties of a permeable water-resistant heat insulation panel based on recycled materials. The insulation panel consists of a thermal insulation core of recycled soft polyurethane foam and winter wheat husk, a layer of geopolymer that gives the entire sandwich composite strength and fire resistance, and a nanofibrous membrane that permits water vapor permeability, but not water in liquid form. The observed properties are the thermal conductivity coefficient, volumetric heat capacity, fire resistance, resistance to long-term exposure of a water column, and the tensile strength perpendicular to the plane of the board. The results showed that while the addition of husk to the thermal insulation core does not significantly impair its thermal insulation properties, the tensile strength perpendicular to the plane of these boards was impaired by the addition of husk. The geopolymer layer increased the fire resistance of the panel for up to 13 min, and the implementation of the nanofibrous membrane resulted in a water flow of 154 cm2 in the amount of 486 g of water per 24 h at a water column height of 0.8 m.

The medicinal plant Swertia multicaulis D. Don was collected in Rasuwa District (Nepal) and the xanthone content of its ethyl acetate extracts was studied. The total amount of xanthones in S. multicaulis determined by HPLC reaches almost 13 g of xanthones per 1 kg of dry matter. The identification of xanthones in S. multicaulis was achieved by a combination of HPLC, LC–MS and LC–NMR. The final assignment of the individual chemical structures was provided by NMR, supported by preparative HPLC. In eight chromatographic peaks, four major xanthones were identified—1,3-dihydroxy-5,8-dimethoxyxanthone, 1-hydroxy-3,5,8-trimethoxyxanthone, bellidifolin (1,5,8-tri-hydroxy-3-methoxyxanthone), and decussatin (1-hydroxy-3,7,8-trimethoxyxanthone).

Objective: Acute aortic dissection is a rare but frequently fatal aortic catastrophe with high morbidity and mortality. Especially in pregnant patients, acute dissection is often misdiagnosed putting two lives on the line. Due to its scarcity, only case reports have been reported. The aim of this study is to analyze the time of aortic dissection during the course of pregnancy and the outcome of emergency surgery in pregnant women with and without hereditary connective tissue disorder. Methods: We retrospectively reviewed all acute aortic dissections (type A and B) who underwent emergency aortic surgery at our institution between 1994 and 2022 and identified 13 patients with acute aortic dissection during pregnancy or directly postpartum. Mann-Whitney U and Fisher's exact tests were used for statistical analysis. Results: Of the 13 included patients, 5 had a genetic syndrome. These patients were significantly younger at the time of dissection and at an earlier stage of pregnancy (second trimester). Even though operative and in-house mortality was zero, we lost one patient on postoperative day 14 due to rupture of the aortic root after transfer to another hospital. Survival of neonates was 77% including two aborted pregnancies. Conclusions : Surgical treatment of acute aortic dissection during pregnancy can be performed with excellent operative mortality for the mothers and satisfying survival of their neonates. In patients with genetic syndrome, dissection occurs during the early second trimester, whereas non-syndromic patients experience acute dissection in the late third trimester. Long-term follow-up is essential for timely re-intervention, if needed.

Background : Placenta accreta spectrum (PAS) can be the cause of major morbidity and its optimal management is still controversial. The aim of this study was to compare the traditional one-step surgery with a two-step surgical approach in which the placenta is left in situ and the second final operation is delayed to minimise blood loss. Methods : We conducted a single-centre retrospective cohort study including all patients managed for PAS between 2007 and 2023. The number of units of red blood cells (RBCs) needed during surgery was the primary outcome used to compare these two approaches. Results : A total of 43 cases were included in this analysis. Twenty of these were managed with the delayed two-step surgical approach, whereas 23 received one-step surgery. The median estimated blood loss during surgery was 2000 mL and 2800 mL for two-step and one-step surgery, respectively ( p = 0.095). In the two-step surgical approach, the median number of RBC units transfused during surgery was significantly lower ( p = 0.049) and the odds ratio for needing more than four units of RBCs was 0.28 (95%-CI: 0.08-0.98, p = 0.043). A longer interval between the caesarean section and the second operation showed a trend toward lower blood loss ( p = 0.065) and was associated with a significantly lower number of RBC units needed during surgery ( p = 0.019). Conclusions : Two-step surgery for the treatment of PAS was safe in our cohort and could lead to a reduction in blood transfusion. Leaving the placenta in situ and delaying the final operation represents a possible alternative to traditional caesarean hysterectomy.

In this prospective, monocentric study, we investigated the potency of a novel three-dimensional (3D) body scanner for external pelvic assessment in birth planning for intended vaginal breech delivery. Between April 2021 and June 2022, 73 singleton pregnancies with intended vaginal birth from breech presentation (>36.0 weeks of gestation) were measured using a pelvimeter by Martin, a three-dimensional body scanner, and MR-pelvimetry. Measures were related to vaginal birth and intrapartum cesarean section. A total of 26 outer pelvic dimensions and 7 inner pelvic measurements were determined. The rate of successful vaginal breech delivery was 56.9%. The AUC (area under the curve) of the obstetric conjugate (OC) measured by MRI for predicting the primary outcome was 0.62 (OR 0.63; p = 0.22), adjusted for neonatal birth weight 0.66 (OR 0.60; p = 0.19). Of the 22 measured 3D body scanner values, the ratio of waist girth to maternal height showed the best prediction (AUC = 0.71; OR 1.27; p = 0.015). The best predictive pelvimeter value was the distantia spinarum with an AUC of 0.65 (OR = 0.80). The 3D body scanner technique is at least equal to predict successful vaginal breech delivery compared to MRI diagnostics. Further large-scale, prospective studies are needed to verify these results.

Transforming growth factor beta-1 (TGFβ1) is an adipokine secreted from adipose tissue, placental tissue and immune cells with a role in cell proliferation, cell apoptosis and angiogenic proliferation. The role of TGFβ1 in pregnancy and child growth and the source of cord TGFβ1 are yet unknown. In this study, we sought to clarify the correlation of TGFβ1 levels with parameters of intrauterine growth and child growth during the first year of life, and to determine whether their source is primarily of fetal or maternal origin. Serum samples and anthropometric measurements were obtained from the LIFE Child cohort of 79 healthy mother-child pairs. Measurements were conducted using enzyme-linked immunosorbent assays. Statistical analyses including Mann-Whitney U-test, correlation analyses and linear regression analyses were performed using GraphPad Prism and R. TGFβ1 levels were significantly higher in cord than in maternal serum, suggesting a fetal origin. Multivariate regression analyses revealed strong positive associations between cord TGFβ1 levels at birth and child weight at U6. Furthermore, cord TGFβ1 was significantly correlated with child weight at approximately one year of age. An increase of 10,000 pg/mL in cord TGFβ1 concentrations at birth was associated with a higher body weight of 201 g at roughly one year of age when adjusted for sex.

Adipokines are signaling proteins involved in metabolic, endocrinological, vascular and immunogenic processes. Associations of various adipokines with not only insulin resistance but also with increased insulin sensitivity, increased systolic blood pressure, and atherosclerosis highlight the significance of adipokines in several components of metabolic syndrome and metabolic diseases in general. As pregnancy presents a unique metabolic state, the role of adipokines in pregnancy, and even in various pregnancy complications, appears to be key to elucidating these metabolic processes. Many studies in recent years have attempted to clarify the role of adipokines in pregnancy and gestational pathologies. In this review, we aim to investigate the changes in maternal adipokine levels in physiological gestation, as well as the association of adipokines with pregnancy pathologies, such as gestational diabetes mellitus (GDM) and preeclampsia (PE). Furthermore, we will analyze the association of adipokines in both maternal serum and cord blood with parameters of intrauterine growth and various pregnancy outcomes.

Background: Peripartum cardiomyopathy (PPCM) is a rare, life-threatening form of heart disease, frequently associated with gene alterations and, in some cases, presenting with advanced heart failure. Little is known about ventricular assist device (VAD) implantation in severe PPCM cases. We describe long-term follow-up of PPCM patients who were resistant to medical therapy and received mechanical circulatory support or heart transplant., Methods and Results: A total of 13 patients were included with mean follow-up of eight years. Mean age of PPCM onset was 33.7 ± 7.7 years. All patients were initially treated with angiotensin-converting enzyme inhibitors and beta-blockers, and four received bromocriptine. Overall, five patients received VADs (three biventricular, two isolated left ventricular) at median 27 days (range: 3 to 150) following childbirth. Two patients developed drive line infection. Due to the short support time, none of those patients had a stroke or VAD thrombosis. In total, five patients underwent heart transplantation, of which four previously had implanted VADs. Median time to transplantation from PPCM onset was 140 days (range: 43 to 776), and time to transplantation from VAD implantation were 7, 40, 132, and 735 days, respectively. All patients survived until most recent follow up, with the exception of one patient who died following unrelated abdominal surgery two years after PPCM recovery., Conclusions: In patients with severe, life-threatening PPCM refractory to medical management, mechanical circulatory support with or without heart transplantation is a safe therapeutic option.