bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical–Epidemiological Characteristics and IFITM-3 (rs12252) Variant Involvement in HIV-1 Mother-to-Children Transmission Susceptibility in a Brazilian Population
Authors: Leandro Dalila Bernardes , Celerino da Silva Ronaldo , Rodrigues Jessyca Kalynne Farias , Leite Maria Carollayne Gonçalves , Arraes Luiz Claudio , Coelho Antonio Victor Campos , Crovella Sergio , Zupin Luisa , Guimarães Rafael Lima
Published: February 2023

Mother-to-children transmission (MTCT) is the main infection route for HIV-1 in children, and may occur during pregnancy, delivery, and/or postpartum. It is a multifactorial phenomenon, where genetic variants play an important role. This study aims at analyzing the influence of clinical epidemiological characteristics and a variant (rs12252) in interferon-induced transmembrane protein 3 (IFITM-3), a gene encoding an important viral restriction factor, on the susceptibility to HIV-1 mother-to-children transmission (MTCT). A case–control study was performed on 209 HIV-1-infected mothers and their exposed infected (87) and uninfected (122) children from Pernambuco, Brazil. Clinical–epidemiological characteristics are significantly associated with MTCT susceptibility. Transmitter mothers have a significantly lower age at delivery, late diagnosis, deficiency in ART use (pregnancy and delivery), and detectable viral load in the third trimester of pregnancy compared with non-transmitter mothers. Infected children show late diagnosis, vaginal delivery frequency, and tend to breastfeed, differing significantly from uninfected children. The IFITM-3 rs12252-C allele and TC/CC genotypes (dominant model) are significantly more frequent among infected than uninfected children, but the statistical significance does not remain when adjusted for clinical factors. No significant differences are observed between transmitter and non-transmitter mothers in relation to the IFITM-3 variant.
Accurate Kidney Pathological Image Classification Method Based on Deep Learning and Multi-Modal Fusion Method with Application to Membranous Nephropathy
Authors: Hao Fang , Liu Xueyu , Li Ming , Han Weixia
Published: February 2023

Membranous nephropathy is one of the most prevalent conditions responsible for nephrotic syndrome in adults. It is clinically nonspecific and mainly diagnosed by kidney biopsy pathology, with three prevalent techniques: light microscopy, electron microscopy, and immunofluorescence microscopy. Manual observation of glomeruli one by one under the microscope is very time-consuming, and there are certain differences in the observation results between physicians. This study makes use of whole-slide images scanned by a light microscope as well as immunofluorescence images to classify patients with membranous nephropathy. The framework mainly includes a glomerular segmentation module, a confidence coefficient extraction module, and a multi-modal fusion module. This framework first identifies and segments the glomerulus from whole-slide images and immunofluorescence images, and then a glomerular classifier is trained to extract the features of each glomerulus. The results are then combined to produce the final diagnosis. The results of the experiments show that the F1-score of image classification results obtained by combining two kinds of features, which can reach 97.32%, is higher than those obtained by using only light-microscopy-observed images or immunofluorescent images, which reach 92.76% and 93.20%, respectively. Experiments demonstrate that considering both WSIs and immunofluorescence images is effective in improving the diagnosis of membranous nephropathy.
Hemodynamic Characteristics of Cardiovascular System in Simulated Zero and Partial Gravities Based on CFD Modeling and Simulation
Authors: Sun Lei , Ding Lijie , Li Lei , Yin Ningning , Yang Nianen , Zhang Yi , Xing Xiaodong , Zhang Zhiyong , Dong Chen
Published: February 2023

Zero and partial gravities (ZPG) increase cardiovascular risk, while the corresponding theoretical foundation remains uncertain. In the article, the ZPG were generated through a rotating frame with two degrees of freedom in combination with the random walk algorithm. A precise 3D geometric configuration of the cardiovascular system was developed, and the Navier-Stokes laminar flow and solid mechanics were used as governing equations for blood flow and the surrounding tissue in the cardiovascular system. The ZPG were designed into governing equations through the volume force term. The computational fluid dynamics’ (CFD) simulations in combination with proper boundary conditions were carried out to investigate the influences of ZPG on the distribution of blood flow velocity, pressure, and shear stress in the cardiovascular system. The findings show that as simulated gravity gradually decreases from 0.7 g to 0.5 g to 0.3 g to 0 g, as opposed to normal gravity of 1 g, the maximum values of blood flow velocity, pressure, and shear stress on the walls of the aorta and its ramification significantly increase, which would lead to cardiovascular diseases. The research will lay a theoretical foundation for the comprehension of the ZPG effect on cardiovascular risk and the development of effective prevention and control measures under the circumstance of ZPG.
Growth Rates, Carcass Traits, Meat Yield, and Fatty Acid Composition in Growing Lambs under Different Feeding Regimes
Authors: Alshamiry Faisal A. , Alharthi Abdulrahman S. , Al-Baadani Hani H. , Aljumaah Riyadh S. , Alhidary Ibrahim A.
Published: February 2023

A total of 75 male Awassi (mean BW 23.5 ± 2.0 kg; 3 months old) were used in an 84-day trial to investigate the effects of different feeding regimes on productive performance, carcass characteristics, and meat quality, and the fatty acid profile of growing lambs. Animals were randomly allocated into 3 groups of 25 lambs each. The dietary treatments were as follows: (1) whole barley grain (60%) plus alfalfa hay (40%; GB-AH; the basal diet); (2) a concentrate pelleted diet plus alfalfa hay (CP-AH); and (3) a complete pelleted diet (CPD). Feed intake was measured weekly, and all lambs were weighed every two weeks for an evaluation of the productive parameters. Blood samples were collected from all lambs for the measurement of biochemical and enzymatic variables. At the end of the experiment, 13 lambs from each treatment were slaughtered to evaluate the carcass characteristics, meat quality, and fatty acid composition. The final body weight, body weight gain, average daily gain, and feed efficiency of lambs were lowest (p < 0.05) in lambs on the grain and alfalfa diet compared with the other groups. Feeding lambs either the CP-AH or CPD diets resulted (p < 0.05) in increases in slaughter weight, carcass weights (hot and cold), the percentage of liver and shoulder, carcass length, back fat thickness, and the area of longissimus thoracis muscle compared with those lambs on the GB-AF diet. The proportion of saturated fatty acids in meat was greater (p = 0.04) in lambs fed on the GA-AH diet than in those of lambs fed on the pelleted diets. Lambs on the CP-AH diet had (p < 0.05) the highest ratios of PUFA to SFA and omega 6 to omega 3, and the proportion of omega 6. The atherogenic and thrombogenic indexes were lower (p < 0.05) in the CP-AH group compared with the GB-AH group. In conclusion, the results indicate that feeding growing lambs on concentrate pellets instead of whole barley grain improves the growth rate, traits, meat quality, and fatty acid profile, which have important implications for productivity, efficiency, and profitability in the livestock industry.
Thymus satureoides Oil as Green Corrosion Inhibitor for 316L Stainless Steel in 3% NaCl: Experimental and Theoretical Studies
Authors: Simescu-Lazar Florica , Slaoui Soukaina , Essahli Mohamed , Bohr Frédéric , Lamiri Abdeslam , Vanoye Laurent , Chopart Jean Paul
Published: February 2023

The protection of 316L stainless steel in 3% NaCl by the essential oil of Thymus satureoides has been studied by many techniques such as potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), atomic force microscopy (AFM) and scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy analysis (EDXS). The results show that the corrosion rate of 316L stainless steel decreases with the increase in the concentration of the inhibitor up to an efficiency of 82% for a concentration of 1600 ppm. The Thymus satureoides oil acts as an anode inhibitor. The values of the inhibition effectiveness obtained from the polarization curves and electrochemical impedance spectroscopy (EIS) are in good agreement. Geometry optimization and calculation of the structural and electronic properties of the inhibitor molecular system have been carried out using density functional theory DFT (B3LYP, BMK and M062X) level with a 6-311++G** basis set.
Tailored Laser Structuring of Tungsten Carbide Cutting Tools for Improving Their Tribological Performance in Turning Aluminum Alloy Al6061 T6
Authors: Baumann Robert , Bouraoui Yasmine , Teicher Uwe , Selbmann Erik , Ihlenfeldt Steffen , Lasagni Andrés Fabián
Published: February 2023

In times of societal development, sustainability has become a major concern for many manufacturers in the metal industries. In this context, surface texturing of cutting tools offers a promising approach in terms of reducing energy consumption and material waste. In this work, direct laser interference patterning is utilized for producing periodic line-like structures with spatial periods of 2.0 µm and 5.5 µm on rake-flank faces of cemented tungsten carbide cutting inserts. Structure depths up to 1.75 µm are reached by controlling the applied number of laser pulses. Turning experiments under lubricated conditions carried out on Al 6061 T6 parts with textured and untreated tools are performed to determine their tribological performances. The used textured cutting tools can effectively decrease machining forces up to 17% due to the corresponding improvement in frictional behavior at the tool/chip interface. Furthermore, the laser-processed tools produce thinner chips and decrease the surface roughness by 31% of the aluminum work piece.
Experimental Studies of Thermophysical Properties and Microstructure of X37CrMoV5-1 Hot-Work Tool Steel and Maraging 350 Steel
Authors: Koniorczyk Piotr , Zieliński Mateusz , Sienkiewicz Judyta , Zmywaczyk Janusz , Dębski Andrzej
Published: February 2023

Measurements of thermal diffusivity, heat capacity and thermal expansion of X37CrMoV5-1 (1.2343) hot-work tool steel and Maraging 350 (1.6355) steel in the temperature range from −50 °C to 1000 °C were carried out in this paper. Both X37CrMoV5-1 and Maraging 350 are tested for military use as barrel steels. Thermophysical properties were tested using specialised test stands from NETZSCH. Thermal diffusivity was studied using both the LFA 427 laser flash apparatus in the temperature range of RT–1000 °C and the LFA 467 laser flash apparatus in the temperature range of −50 °C–500 °C. Specific heat capacity was investigated using a DSC 404 F1 Pegasus differential scanning calorimeter in the range RT–1000 °C, and thermal expansion was investigated using both a DIL 402 Expedis pushrod dilatometer in the range −50 °C–500 °C and a DIL 402 C in the range RT–1000 °C. Inconel 600 was selected as the reference material during the thermal diffusivity test using LFA467. Tests under the light microscope (LM), scanning electron microscopy (SEM) and Vickers microhardness measurements were carried out to detect changes in the microstructure before and after thermophysical measurements. This paper briefly characterises the research procedures used. In conclusion, the results of testing the thermophysical properties of X37CrMoV5-1 hot-work tool steel and Maraging 350 steel are compared with our results on 38HMJ (1.8509), 30HN2MFA and Duplex (1.4462) barrel steels. The thermophysical properties of X37CrMoV5-1 (1.2343) hot-work tool steel and Maraging 350 (1.6355) steel are incomplete in the literature. The paper presents the thermophysical properties of these steels over a wide range of temperatures so that they can be used as input data for numerical simulations of heat transfer in cannon barrels.
Characterization of Zr-Containing Dispersoids in Al–Zn–Mg–Cu Alloys by Small-Angle Scattering
Authors: Honaramooz Mohammad Taha , Morak Roland , Pogatscher Stefan , Fritz-Popovski Gerhard , Kremmer Thomas M. , Meisel Thomas C. , Österreicher Johannes A. , Arnoldt Aurel , Paris Oskar
Published: February 2023

The characterization of Zr-containing dispersoids in aluminum alloys is challenging due to their broad size distribution, low volume fraction, and heterogeneous distribution within the grains. In this work, small-angle X-ray scattering (SAXS) and small-angle neutron scattering (SANS) were compared to scanning electron microscopy (SEM) and transmission electron microscopy (TEM) regarding their capability to characterize Zr-containing dispersoids in aluminum alloys. It was demonstrated that both scattering techniques are suitable tools to characterize dispersoids in a multi-phase industrial 7xxx series aluminum alloy. While SAXS is more sensitive than SANS due to the high electron density of Zr-containing dispersoids, SANS has the advantage of being able to probe a much larger sample volume. The combination of both scattering techniques allows for the verification that the contribution from dispersoids can be separated from that of other precipitate phases such as the S-phase or GP-zones. The size distributions obtained from SAXS, SANS and TEM showed good agreement. The SEM-derived size distributions were, however, found to significantly deviate from those of the other techniques, which can be explained by considering the resolution-limited restrictions of the different techniques.
Grain Refinement Mechanisms of TiC0.5N0.5 Nanoparticles in Aluminum
Authors: Wang Kui , Jiang Haiyan , Wang Qudong , Wang Yingxin
Published: February 2023

In this study, TiC0.5N0.5 nanoparticles (NPs) are shown to induce a remarkable grain refinement of aluminum at various cooling rates. The grain refinement mechanisms are systematically investigated by microstructure observation, edge-to-edge matching (E2EM) model prediction, and first-principles calculations. The experimental results suggest that as the cooling rates increase from 10 K/s to 70 K/s, a transition from intergranular to intragranular distribution of NPs occurs and the Al/TiC0.5N0.5 interface varies from incoherent to coherent. Based on the E2EM analysis combined with first-principles calculation, it is found that TiC0.5N0.5 can act as a potent nucleant for the heterogeneous nucleation of α-Al. By analyzing the NP effects on the nucleation and growth of α-Al, the grain growth restriction and nucleation promotion mechanisms are proposed to elucidate the refinement phenomena at low and high cooling conditions, respectively.
Possibilities of a Hybrid Method for a Time-Scale-Frequency Analysis in the Aspect of Identifying Surface Topography Irregularities
Authors: Gogolewski Damian , Zmarzły Paweł , Kozior Tomasz , Mathia Thomas G.
Published: February 2023

The article presents research results related to assessing the possibilities of applying modern filtration methods to diagnosing measurement signals. The Fourier transformation does not always provide full information about the signal. It is, therefore, appropriate to complement the methodology with a modern multiscale method: the wavelet transformation. A hybrid combination of two algorithms results in revealing additional signal components, which are invisible in the spectrum in the case of using only the harmonic analysis. The tests performed using both simulated signals and the measured roundness profiles of rollers in rolling bearings proved the advantages of using a complex approach. A combination of the Fourier and wavelet transformations resulted in the possibility to identify the components of the signal, which directly translates into better diagnostics. The tests fill a research gap in terms of complex diagnostics and assessment of profiles, which is very important from the standpoint of the precision industry.
Development of TiO2 Nanosheets with High Dye Degradation Performance by Regulating Crystal Growth
Authors: Kowaka Yasuyuki , Nozaki Kosuke , Mihara Tomoyuki , Yamashita Kimihiro , Miura Hiroyuki , Tan Zhenquan , Ohara Satoshi
Published: February 2023

TiO2 nanosheets have been studied as photocatalysts in various fields, and their performance has been actively improved. Herein, we prepared titania nanosheets with a smaller size than those reported previously with a side length of 29 nm and investigated their photocatalytic activity. (NH4)2TiF6 and Ti(OBu)4 were used as raw materials, and the F/Ti ratio was varied in the range of 0.3 to 2.0 to produce a series of samples with different side lengths by hydrothermal synthesis. A reduction in the F/Ti ratio led to the reduced size of the titanium nanosheets. The photocatalytic activity of each sample was evaluated through the degradation of methylene blue (MB) under ultraviolet (UV) irradiation (365 nm, 2.5 mW/cm2). UV irradiation promoted the decomposition of MB, and the highest degradation efficiency was achieved using titania nanosheets prepared with a F/Ti ratio of 0.3. The high catalytic activity can be attributed to the increase in the surface area due to size reduction. The ratio of the {001} surface exposed on the titania nanosheet also affected the photocatalytic activity; it resulted in increased activation of the reaction. This study demonstrates that further activation of the photocatalytic activity can be achieved by adjusting the size of titania nanosheets.
Out-of-Plane Compression Behaviour of Aluminum Alloy Large-Scale Super-Stub Honeycomb Cellular Structures
Authors: Lin Song , Yuan Meini , Zhao Bing , Li Beibei
Published: February 2023

The out-of-plane compression behaviour of 6061-T6 aluminum alloy super-stub honeycomb cellular structures without and with friction stir welding (FSW) facesheets are presented in this paper. A total of twelve axially compressed experiments on large-scale specimens, six with square hollow section (SHS) cores and six with hexagonal hollow section (HHS) cores, were conducted, with failure modes, ultimate resistances and axial load-end shortening curves analysed. The accuracy of finite element (FE) models was validated in accordance with test results. The numerical data obtained from extensive parametric analyses combined with test data were subsequently used to evaluate the applicability of existing design rules in Chinese, European and American aluminium alloy specifications. The results showed that the three specifications generally yielded very conservative predictions for the out-of-plane compression resistances of SHS and HHS super-stub honeycomb cores without and with FSW facesheets by about 30–37%. Design recommendations on the cross-section effective thickness are finally proposed and shown to provide much more accurate and consistent predictions than current design methods. The research results are beneficial to the application and development of large-scale super-stub honeycomb structures in structural engineering, such as the helicopter landing platforms, the base of fluid and gas tanks and ship decks.
The Safety of Fluoride Compounds and Their Effect on the Human Body—A Narrative Review
Authors: Lubojanski Adam , Piesiak-Panczyszyn Dagmara , Zakrzewski Wojciech , Dobrzynski Wojciech , Szymonowicz Maria , Rybak Zbigniew , Mielan Bartosz , Wiglusz Rafal J. , Watras Adam , Dobrzynski Maciej
Published: February 2023

Fluoride is one of the elements commonly present in the human environment. Due to its characteristics, it is very widely used in medicine, dentistry, industry or agriculture. On the other hand, its universality possesses a real threat to the human body in the form of acute and chronic poisoning. The aim of this paper is to characterize the properties of fluoride and its effects on the human body, as well as the sources of its occurrence. Particular emphasis is placed on the safety of its use and optimal dosage intake, which prevents accumulation and reduces its potential side effects. The positive effect of proper fluoride supply is widely described. In order to avoid overdose, it is best to consult a specialist to properly select the dosage.
Time-Varying Pattern and Prediction Model for Geopolymer Mortar Performance under Seawater Immersion
Authors: Wu Yingjie , Du Kun , Wu Chengqing , Tao Ming , Zhao Rui
Published: February 2023

In this study, immersion experiments were conducted on the geopolymer mortar (GPM) by using artificial seawater, and the effects of alkali equivalent (AE) and waterglass modulus (WGM) on the resistance of geopolymer mortar (GPM) to seawater immersion were analyzed. The test subjected 300 specimens to 270 days of artificial seawater immersion and periodic performance tests. Alkali equivalent (AE) (3–15%) and waterglass modulus (WGM) (1.0–1.8) were employed as influencing factors, and the mass loss and uniaxial compressive strength (UCS) were used as the performance evaluation indexes, combined with X-ray diffraction (XRD) and scanning electron microscopy (SEM) to analyze the time-varying pattern of geopolymer mortar (GPM) performance with seawater immersion. The findings demonstrated a general trend of initially growing and then declining in the uniaxial compression strength (UCS) of geopolymer mortar (GPM) under seawater immersion. The resistance of geopolymer mortar (GPM) to seawater immersion decreased with both higher or lower alkali equivalent (AE), and the ideal range of alkali equivalent (AE) was 9–12%. The diffusion layer of the bilayer structure of the waterglass particle became thinner with an increase in waterglass modulus (WGM), which ultimately led to the reduction in the resistance of the geopolymer structure to seawater immersion. Additionally, a support vector regression (SVR) model was developed based on the experimental data to predict the uniaxial compression strength (UCS) of GPM under seawater immersion. The model performed better and was able to achieve accurate prediction within 1–2 months, and provided an accurate approach to predicting the strength of geopolymer materials in a practical offshore construction project.
Towards Highly Efficient, Additively Manufactured Passive Vibration Eliminators for Mechanical Systems
Authors: Irska Izabela , Kramek Grzegorz , Miądlicki Karol , Dunaj Paweł , Berczyński Stefan , Piesowicz Elżbieta
Published: February 2023

Structural damping largely determines the dynamic properties of mechanical structures, especially those whose functioning is accompanied by time-varying loads. These loads may cause vibrations of a different nature, which adversely affects the functionality of the structure. Therefore, many studies have been carried out on vibration reduction methods over the last few years. Among them, the passive vibration damping method, wherein a suitable polymer system with appropriate viscoelastic properties is used, emerges as one of the simplest and most effective methods. In this view, a novel approach to conduct passive elimination of vibrations, consisting of covering elements of structures with low dynamic stiffness with polymeric pads, was developed. Herein, polymer covers were manufactured via fused filament fabrication technology (3D printing) and were joined to the structure by means of a press connection. Current work was focused on determining the damping properties of chosen polymeric materials, including thermoplastic elastomers (TPE). All investigated materials were characterized by means of differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), and mechanical properties (tensile test and Shore hardness). Lastly, the damping ability of pads made from different types of polymers were evaluated by means of dynamic tests.
Patterning of Polymer-Functionalized Nanoparticles with Varied Surface Mobilities of Polymers
Authors: Gong Shuting , Wang Tianyi , Lin Jiaping , Wang Liquan
Published: February 2023

The polymers can be either dynamically tethered to or permanently grafted to the nanoparticle to produce polymer-functionalized nanoparticles. The surface mobility of polymer ligands with one end anchored to the nanoparticle can affect the surface pattern, but the effect remains unclear. Here, we addressed the influence of lateral polymer mobility on surface patterns by performing self-consistent field theory calculations on a modeled polymer-functionalized nanoparticle consisting of immobile and mobile brushes. The results show that except for the radius of nanoparticles and grafting density, the fraction of mobile brushes substantially influences the surface patterning of polymer-functionalized nanoparticles, including striped patterns and patchy patterns with various patches. The number of patches on a nanoparticle increases as the fraction of mobile brushes decreases, favored by the entropy of immobile brushes. Critically, we found that broken symmetry usually occurs in patchy nanoparticles, associated with the balance of enthalpic and entropic effects. The present work provides a fundamental understanding of the dependence of surface patterning on lateral polymer mobility. The work could also guide the preparation of diversified nanopatterns, especially for the asymmetric patchy nanoparticles, enabling the fundamental investigation of the interaction between polymer-functionalized nanoparticles.
Screening Critical Design Parameters for Electromechanical Products Performance Matching Based on Energy and Causal Model
Authors: Wang Xiang , Xiang Dong
Published: February 2023

The design parameters are the most momentous factors in carrying out performance matching. For complex electromechanical products with a large number of design parameters, determining a set of critical design parameters which have a great influence on the performance is the premise of performance matching. In this paper, from a systematic perspective, a screening method of critical design parameters based on energy and a causal model is proposed. Since energy is the driving force of the product operation to achieve performance, the design parameters affect the performance through energy flow in the product. Therefore, the causal model among design parameters, characteristic energy, and performance is established, where its path coefficients are determined based on the quantitative calculation of the energy flow simulation model. Then, the performance pertinence is defined and calculated to describe the comprehensive influence of the design parameters on performance and to screen the critical parameters. Finally, the performance matching process is presented to support the performance matching. With a refrigerator as an example, 5 parameters were screened from 11 variable design parameters, and day power consumption decreased by 6.85%, which verifies the effectiveness of the method.
On the Internal Counter-Torque between Springs in Serially Connected Statically Balanced Manipulators
Authors: Jhuang Chi-Shiun , Juang Chia-Wei , Shih Cheng-Hsin , Chen Dar-Zen
Published: February 2023

Serially connected statically balanced manipulators with springs have been used in many applications. However, a portion of the torques caused by springs countering each other lead to an imbalance in gravitational torques and, therefore, are deemed as waste torques for springs to achieve static balance. In this paper, the torque contribution of a typical spring is classified as gravity-balancing torque and counter-torque based on the accumulated joint angle of the gravitational torque. Then, the internal counter-torque is defined as the sum of the magnitude of the terms of these counter-torques at each joint. Through the adjustment of spring attachment parameters, the internal counter-torque can be minimized with preferable spring attachment parameters while maintaining a static-balancing condition. A typical four-link manipulator with a preselected spring configuration is shown as an illustrative example. The results show that there are 28% and 50% reductions in the internal counter-torque at joints 2 and 3, respectively, through the adjustment of spring attachment parameters. Hence, the waste torques in statically balanced serially connected manipulators are reduced to the lowest quantity.
A Comparative Analysis of Numerical Methods for Solving the Leaky Integrate and Fire Neuron Model
Authors: Masri Ghinwa El , Ali Asma , Abuwatfa Waad H. , Mortula Maruf , Husseini Ghaleb A.
Published: February 2023

The human nervous system is one of the most complex systems of the human body. Understanding its behavior is crucial in drug discovery and developing medical devices. One approach to understanding such a system is to model its most basic unit, neurons. The leaky integrate and fire (LIF) method models the neurons’ response to a stimulus. Given the fact that the model’s equation is a linear ordinary differential equation, the purpose of this research is to compare which numerical analysis method gives the best results for the simplified version of this model. Adams predictor and corrector (AB4-AM4) and Heun’s methods were then used to solve the equation. In addition, this study further researches the effects of different current input models on the LIF’s voltage output. In terms of the computational time, Heun’s method was 0.01191 s on average which is much less than that of the AB-AM4 method (0.057138) for a constant DC input. As for the root mean square error, the AB-AM4 method had a much lower value (0.0061) compared to that of Heun’s method (0.3272) for the same constant input. Therefore, our results show that Heun’s method is best suited for the simplified LIF model since it had the lowest computation time of 36 ms, was stable over a larger range, and had an accuracy of 72% for the varying sinusoidal current input model.
In Vitro Bioaccessibility of Proteins and Bioactive Compounds of Wild and Cultivated Seaweeds from the Gulf of Saint Lawrence
Authors: Vasconcelos Margarida M. M. , Marson Gabriela V. , Rioux Laurie-Eve , Tamigneaux Eric , Turgeon Sylvie L. , Beaulieu Lucie
Published: February 2023

Despite the increased interest in macroalgae protein and fibers, little information is available on their bioaccessibility. The application of an in vitro gastrointestinal digestion model to study the degree of disintegration and release of proteins with expressed bioactivities from wild and cultivated Palmaria palmata and Saccharina latissima was proposed in this study. Macroalgae from the Gulf of St Lawrence, Canada, were submitted to digestive transit times of 2 (oral), 60 (gastric) and 120 (duodenal) minutes. Among wild samples, P. palmata had a higher percentage of disintegration, protein release and degree of hydrolysis than S. latissima. While the least digested sample, wild S. latissima, was the sample with the highest antioxidant activity (210 μmol TE g−1), the most digested sample, cultivated P. palmata, presented the highest ability to inhibit the angiotensin-converting enzyme (ACE), reaching 32.6 ± 1.2% at 3 mg mL−1. ACE inhibitory activity increased from 1 to 3 mg mL−1, but not at 5 mg mL−1. Wild samples from both species showed an ACE inhibition around 27.5%. Data suggested that the disintegration of the samples was influenced by their soluble and insoluble fiber contents. Further information on the bioaccessibility and bioactivity of these macroalgae should consider the characterization of digestion products other than protein, as well as the effects of previous product processing.
Design, Synthesis, Antifungal Activity, and Molecular Docking of Streptochlorin Derivatives Containing the Nitrile Group
Authors: Liu Jing-Rui , Gao Ya , Jin Bing , Guo Dale , Deng Fang , Bian Qiang , Zhang Hai-Feng , Han Xin-Ya , Ali Abdallah S. , Zhang Ming-Zhi , Zhang Wei-Hua , Gu Yu-Cheng
Published: February 2023

Based on the structures of natural products streptochlorin and pimprinine derived from marine or soil microorganisms, a series of streptochlorin derivatives containing the nitrile group were designed and synthesized through acylation and oxidative annulation. Evaluation for antifungal activity showed that compound 3a could be regarded as the most promising candidate—it demonstrated over 85% growth inhibition against Botrytis cinerea, Gibberella zeae, and Colletotrichum lagenarium, as well as a broad antifungal spectrum in primary screening at the concentration of 50 μg/mL. The SAR study revealed that non-substituent or alkyl substituent at the 2-position of oxazole ring were favorable for antifungal activity, while aryl and monosubstituted aryl were detrimental to activity. Molecular docking models indicated that 3a formed hydrogen bonds and hydrophobic interactions with Leucyl-tRNA Synthetase, offering a perspective for the possible mechanism of action for antifungal activity of the target compounds.
Enzyme Inhibitors from Gorgonians and Soft Corals
Authors: Córdova-Isaza Andrea , Jiménez-Mármol Sofía , Guerra Yasel , Salas-Sarduy Emir
Published: February 2023

For decades, gorgonians and soft corals have been considered promising sources of bioactive compounds, attracting the interest of scientists from different fields. As the most abundant bioactive compounds within these organisms, terpenoids, steroids, and alkaloids have received the highest coverage in the scientific literature. However, enzyme inhibitors, a functional class of bioactive compounds with high potential for industry and biomedicine, have received much less notoriety. Thus, we revised scientific literature (1974–2022) on the field of marine natural products searching for enzyme inhibitors isolated from these taxonomic groups. In this review, we present representative enzyme inhibitors from an enzymological perspective, highlighting, when available, data on specific targets, structures, potencies, mechanisms of inhibition, and physiological roles for these molecules. As most of the characterization studies for the new inhibitors remain incomplete, we also included a methodological section presenting a general strategy to face this goal by accomplishing STRENDA (Standards for Reporting Enzymology Data) project guidelines.
Diversity and Distribution of Carotenogenic Algae in Europe: A Review
Authors: Chekanov Konstantin
Published: February 2023

Microalgae are the richest source of natural carotenoids, which are valuable pigments with a high share of benefits. Often, carotenoid-producing algae inhabit specific biotopes with unfavorable or even extremal conditions. Such biotopes, including alpine snow fields and hypersaline ponds, are widely distributed in Europe. They can serve as a source of new strains for biotechnology. The number of algal species used for obtaining these compounds on an industrial scale is limited. The data on them are poor. Moreover, some of them have been reported in non-English local scientific articles and theses. This review aims to summarize existing data on microalgal species, which are known as potential carotenoid producers in biotechnology. These include Haematococcus and Dunaliella, both well-known to the scientific community, as well as less-elucidated representatives. Their distribution will be covered throughout Europe: from the Greek Mediterranean coast in the south to the snow valleys in Norway in the north, and from the ponds in Amieiro (Portugal) in the west to the saline lakes and mountains in Crimea (Ukraine) in the east. A wide spectrum of algal secondary carotenoids is reviewed: β-carotene, astaxanthin, canthaxanthin, echinenone, adonixanthin, and adonirubin. For convenience, the main concepts of biology of carotenoid-producing algae are briefly explained.
Ozone Diffusion through a Hollow Fiber Membrane Contactor for Pharmaceuticals Removal and Bromate Minimization
Authors: Schmitt Alice , Mendret Julie , Cheikho Hani , Brosillon Stephan
Published: February 2023

Recently, ozonation has been advocated as a solution to tackle emerging contaminants. Hollow fiber membrane contactors (HFMC) have a lower residual ozone concentration than bubble reactors that could limit the formation of potential ozonation by-products, especially bromates that are regulated in drinking water. The aim of this study was to evaluate ozonation with HFMC for pharmaceutical abatement and bromate minimization compared to bubble columns in wastewater. A HFMC, composed of 65 polytetrafluoroethylene hollow fibers with a 0.45 mm/0.87 mm inner/external diameter and a 0.107 m² exchange surface, was used for the ozonation of real-treated wastewater spiked with 2 µM of p-chlorobenzoic acid (p-CBA) and 3 mg.L−1 of bromide. p-CBA was tracked to monitor the production of strongly-oxidant hydroxyl radicals from the decomposition of the molecular ozone. At 100% p-CBA abatement, 1600 µg.L−1 of bromate was formed with the HFMC, whereas 3486 µg.L−1 was formed with the bubble column. These results demonstrate that HFMC can produce a significant amount of hydroxyl radicals while limiting bromate formation in real-treated wastewater. The test water was also spiked with carbamazepine and sulfamethoxazole to evaluate the abatement efficiency of the process. Short contact times (approximately 2s) achieved high rates of pharmaceuticals removal without bromate formation.
A Novel Tri-Functionality pH-Magnetic-Photocatalytic Hybrid Organic-Inorganic Polyoxometalates Augmented Microspheres for Polluted Water Treatment
Authors: Yee Li Ying , Ng Qi Hwa , Enche Ab Rahim Siti Kartini , Hoo Peng Yong , Chang Pei Thing , Ahmad Abdul Latif , Low Siew Chun , Shuit Siew Hoong
Published: February 2023

The severe water pollution from effluent dyes threatens human health. This study created pH-magnetic-photocatalytic polymer microspheres to conveniently separate the photocatalyst nanoparticles from the treated water by applying an external magnetic field. While fabricating magnetic nanoparticles’ (MNPs) microspheres, incorporating 0.5 wt.% iron oxide (Fe3O4) showed the best magnetophoretic separation ability, as all the MNPs microspheres were attracted toward the external magnet. Subsequently, hybrid organic–inorganic polyoxometalates (HPOM), a self-synthesized photocatalyst, were linked with the functionalized magnetic nanoparticles (f-MNPs) to prepare augmented magnetic-photocatalytic microspheres. The photodegradation dye removal efficiency of the augmented magnetic-photocatalytic microspheres (f-MNPs-HPOM) was then compared with that of the commercial titanium dioxide (TiO2) photocatalyst (f-MNPs-TiO2). Results showed that f-MNPs-HPOM microspheres with 74 ± 0.7% photocatalytic removal efficiency better degraded methylene orange (MO) than f-MNPs-TiO2 (70 ± 0.8%) at an unadjusted pH under UV-light irradiation for 90 min. The excellent performance was mainly attributed to the lower band-gap energy of HPOM (2.65 eV), which required lower energy to be photoactivated under UV light. The f-MNPs-HPOM microspheres demonstrated excellent reusability and stability in the photo-decolorization of MO, as the microspheres retained nearly the same removal percentage throughout the three continuous cycles. The degradation rate was also found to follow the pseudo-first-order kinetics. Furthermore, f-MNPs-HPOM microspheres were pH-responsive in the photodegradation of MO and methylene blue (MB) at pH 3 (acidic) and pH 9 (alkaline). Overall, it was demonstrated that using HPOM photocatalysts in the preparation of magnetic-photocatalytic microspheres resulted in better dye degradation than TiO2 photocatalysts.
Influence of Structural Parameters on Mechanical Properties of Triply Periodic Minimal Surface Structure
Authors: Chen Xiusi , Sun Guoqin , Zhu Jiaqi , Kang Wei , Shang Deguang , Deng Zhanfeng
Published: February 2023

Titanium alloy is widely used in aerospace and other fields due to its low density, high specific strength, corrosion resistance, and other advantages. With the development of selective laser melting additive manufacturing technology, it is possible to manufacture triply periodic minimal surface porous structures. The effects of structural parameters on the mechanical properties of a Ti-6Al-4V Diamond (D)-type triply periodic minimal surface structure are studied. According to the characteristics of porous structures, the Gibson Ashby fitting formulas of D structures are modified using the concept of equivalent cross-sectional areas. The influence of cell size and surface thickness on the compressive modulus and strength of a D structure is discussed. Prediction formulas of the mechanical properties based on cell size and surface thickness are established by combining the relative density with the structural parameters. On this basis, the density optimization method is applied to the lightweight design of a rocket-related assembly based on D structure filling. The design results verify the feasibility of a lightweight design based on triply periodic minimal surface structure filling.
Manufacturing Methods Induced Property Variations in Ti6Al4V Using High-Speed Machining and Additive Manufacturing (AM)
Authors: Yadav Shivam Pradeep , Pawade Raju S.
Published: February 2023

Additive manufacturing techniques are replacing conventional subtractive machining processes; however, the surface quality and defects have been a key roadblock to expanding AM’s uses. This paper describes experimental investigations in the high-speed dry machining and additive manufacturing (AM) of titanium alloy (Ti6Al4V), discussing the effect of machining and AM conditions on the surface characteristics due to the micro-deformation layer. Analysis of the machined surfaces shows the deposition of microparticles at a high cutting speed of 170 m/min at moderate feed rates. The predominant thermal softening effect at a high cutting speed causes restructuring of the micro-deformation layer. Thus, the machined surface shows fewer alterations and a correspondingly lower surface roughness. A high cutting speed also favors the induction of high residual stresses that are compressive. Shallow grooves are seen throughout the surface along the feed spacing with a higher depth of cut of 0.8 mm. An increase in the cutting speed from 170 m/min to 190 m/min leads to a 61% increase in the surface finish owing to a rise in machining temperature leading to thermal softening, and subsequent restructuring of the machined surface layer occurs. For the feed rate, the surface finish values decrease gradually as the feed rate increases, and the worst finish of 1.37 µm is attained at a feed rate of 0.875 mm/rev. This study also compares different AM processes for Ti6Al4V based on the defects and their effects on mechanical properties, such as tensile and fatigue strength. It was observed that the ultimate tensile strength and the yield strength were approximately 20% more in SLM and direct energy deposition as compared to electron beam melting. The mechanism of these effects is also explained by elaborating on the influence of grain size, phase, and other microstructural behaviors on the final mechanical properties of the produced part.
Large Magnetic Entropy Change in GdRuSi Optimal for Magnetocaloric Liquefaction of Nitrogen
Authors: Kuchin Anatoly G. , Platonov Sergey P. , Mukhachev Roman D. , Lukoyanov Alexey V. , Volegov Aleksey S. , Gaviko Vasilii S. , Yakovleva Mari Yu.
Published: February 2023

The search for new magnetocaloric materials for application in magnetic refrigerants is highly motivated by high efficiency, reliability, and environmental safety. The values of the magnetocaloric effect MCE and the refrigerant capacity RC for the equiatomic GdRuSi compound were determined to be MCE = 10.7 and 4.94 J/kgK and RC = 336 and 92 J/kg with a change in the field of 0–50 and 0–17 kOe, respectively. These high values of MCE and RC for GdRuSi appear in the region of nitrogen liquefaction temperature of 77.4 K, due to which the compound can be useful in practice. The densities of states and magnetic moments of GdRuSi were calculated theoretically, taking into account strong electron correlations in the 4f Gd shell. The total magnetic moment of GdRuSi was found to be composed of the Gd moment only with the value calculated in very good agreement with the experimental one.
Characterization of Corrosion Behavior and Corrosion Production Property of 90-10 Cupronickel Welding Joints in Flowing Seawater
Authors: Xing Shaohua , Bai Shuyu , Liu Ran , Liu Yingshuang , Qi Jiantao , Hou Jian , Zhang Dalei
Published: February 2023

Due to its excellent performance, 90-10 cupronickel has been widely used as a pipeline for marine engineering. However, due to the harsh service conditions of flowing seawater, the problem of corrosion leakage is extremely serious. One of the most common locations is the welding joint. In this paper, electrochemical impedance spectroscopy, surface morphology analysis techniques (scanning electron spectroscopy, energy disperse spectroscopy, three-dimensional microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy) are used to study the corrosion resistance of 90-10 cupronickel (MZ), heat affected zone (HAZ) and welding zone (WZ). The experimental results show that MZ, HAZ and WZ can form protective corrosion product film in flowing seawater, and that the corrosion resistance increases with the experiment time increasing and achieves the maximum value after 20 days. However, the corrosion resistance of HAZ is smallest due to the low adhesion density of corrosion production formed on HAZ. HAZ is preferentially corroded for minimum corrosion resistance and galvanic corrosion between WZ and HAZ.
Mucopolysaccharidosis Type 1 among Children—Neuroradiological Perspective Based on Single Centre Experience and Literature Review
Authors: Machnikowska-Sokołowska Magdalena , Myszczuk Aleksandra , Wieszała Emilia , Wieja-Błach Dominika , Jamroz Ewa , Paprocka Justyna
Published: February 2023

Mucopolysaccharidosis 1 (MPS 1) is a group of rare lysosomal genetic disorders resulting from the accumulation of undegraded glycosaminoglycans (GAGs) leading to multiorgan damage. Neurological symptoms vary from mild to severe. Neuroimaging—mainly magnetic resonance (MRI)—plays a crucial role in disease diagnosis and monitoring. Early diagnosis is of the utmost importance due to the necessity of an early therapy implementation. New imaging tools like MR spectroscopy (MRS), semiquantitative MRI analysis and applying scoring systems help substantially in MPS 1 surveillance. The presented analysis of neuroimaging manifestations is based on 5 children with MPS 1 and a literature review. The vigilance of the radiologist based on knowledge of neuroradiological patterns is highlighted.
Creep Feeding and Weaning Influence the Postnatal Evolution of the Plasma Metabolome in Neonatal Piglets
Authors: Metzler-Zebeli Barbara U. , Lerch Frederike , Yosi Fitra , Vötterl Julia C. , Koger Simone , Aigensberger Markus , Rennhofer Patrick M. , Berthiller Franz , Schwartz-Zimmermann Heidi E.
Published: February 2023

Data on the evolution of blood metabolites and metabolic markers in neonatal piglets are scarce, although this information is vital to detect physiological aberrations from normal development. We aimed to characterize age- and nutrition-related changes in the plasma metabolome and serum biochemistry of suckling and newly weaned piglets and assess metabolite patterns as physiological markers for the two phases. In two replicate batches (n = 10 litters/group), piglets either received sow milk alone or were additionally offered creep feed from day 10 until weaning (day 28). Blood was collected from one piglet/litter on days 7, 14, 21, 28, 31 and 35 of life, totaling five females and five males/group/day. Signature feature ranking identified plasma triglycerides (TG) as discriminative for age and nutrition during the suckling phase. Influential TG 20:4_36:5, TG 17:0_34:2 and TG 18:2_38:6 were higher in creep-fed piglets on days 14, 21 and 28 of life, respectively, compared to only sow milk-fed piglets. Metabolites belonging to pathways within histidine, D-glutamine and D-glutamate metabolism as well as hippuric acid were distinctive for the postweaning compared to the suckling period. In conclusion, plasma lipid profiles especially corresponded to the type of nutrition in the suckling phase and showed a strong weaning effect.