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Nowadays, the oral use of probiotics is widespread. However, the safety profile with the use of live probiotics is still a matter of debate. Main risks include: Cases of systemic infections due to translocation, particularly in vulnerable patients and pediatric populations; acquisition of antibiotic resistance genes; or interference with gut colonization in neonates. To avoid these risks, there is an increasing interest in non-viable microorganisms or microbial cell extracts to be used as probiotics, mainly heat-killed (including tyndallized) probiotic bacteria (lactic acid bacteria and bifidobacteria). Heat-treated probiotic cells, cell-free supernatants, and purified key components are able to confer beneficial effects, mainly immunomodulatory effects, protection against enteropathogens, and maintenance of intestinal barrier integrity. At the clinical level, products containing tyndallized probiotic strains have had a role in gastrointestinal diseases, including bloating and infantile coli—in combination with mucosal protectors—and diarrhea. Heat-inactivated probiotics could also have a role in the management of dermatological or respiratory allergic diseases. The reviewed data indicate that heat-killed bacteria or their fractions or purified components have key probiotic effects, with advantages versus live probiotics (mainly their safety profile), positioning them as interesting strategies for the management of common prevalent conditions in a wide variety of patients´ characteristics.

HighlightsExcellent impedance matching through component modulation engineering.Rich heterogeneous interfaces are constructed to realize excellent electromagnetic wave (EMW) absorption performance. Long-term corrosion protection and excellent EMW absorption properties.Currently, the demand for electromagnetic wave (EMW) absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly urgent. Multi-component interface engineering is considered an effective means to achieve high-efficiency EMW absorption. However, interface modulation engineering has not been fully discussed and has great potential in the field of EMW absorption. In this study, multi-component tin compound fiber composites based on carbon fiber (CF) substrate were prepared by electrospinning, hydrothermal synthesis, and high-temperature thermal reduction. By utilizing the different properties of different substances, rich heterogeneous interfaces are constructed. This effectively promotes charge transfer and enhances interfacial polarization and conduction loss. The prepared SnS/SnS2/SnO2/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt% in epoxy resin. The minimum reflection loss (RL) is − 46.74 dB and the maximum effective absorption bandwidth is 5.28 GHz. Moreover, SnS/SnS2/SnO2/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel surfaces. Therefore, this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.

To investigate the dynamic interaction between refining refractory and low‐carbon low‐silicon Al‐killed steel, the “refractory‐molten steel‐inclusion” system was analyzed using dynamic erosion experiments and the FactSage database. This study discussed the formation of interfacial layers between various refining refractories and molten steel, as well as the transformation of nonmetallic inclusions in steel. The findings indicate that the interaction between refractories and molten steel produces a distinct interface layer. The influence of various refining refractories on inclusions varies significantly. MgO‐C refractory promotes the formation of MgO·Al2O3 inclusions in steel, while Al2O3‐MgO refractory leads to the formation of SiO2‐MnO‐Al2O3 inclusions. Both Al2O3‐SiC refractory and Al2O3‐MgO‐C refractory result in Al2O3 inclusions with trace levels of MgO. Steel refined with Al2O3‐MgO‐C refractory has increased MgO content within Al2O3 inclusions but still does not reach the stoichiometric ratio of MgO·Al2O3. As the initial Al content increases, the influence of MgO‐C refractory inclusions becomes increasingly noticeable. The average MgO content within the inclusions rises with the reaction duration, achieving as high as 62.9%. The transition path of Al2O3 inclusions in molten steel follows “Al2O3→MgO·Al2O3→MgO.”

In this work, Ti 3 C 2 MXene, a novel two-dimensional nanosheet, was introduced to waterborne polyurethane (WPU) coatings to prepare a composite coating. First, MAX phase materials were in situ etched by HF acid and further intercalated by water molecules to obtain exfoliated single-layer MXene nanosheet. And then, composite coatings were prepared via solution-blending low addition (0–0.4 wt%) of MXene, self-prepared waterborne polyacrylate emulsion (PAE) and isocyanate hardener, applying on Q235 mild steel. Results of AFM, XRD SEM and SEM–EDS confirm that single-layer MXene nanosheets with large lateral-to-thickness ratio are successfully prepared and achieved homogenous distribution within WPU matrix. With 0.4 wt% MXene incorporated, the WPU/Ti 3 C 2 MXene composite coatings reach a lowest corrosion current of 2.143 × 10 –6  A/cm 2 , a decrease of one order of magnitude compared with blank WPU (1.599 × 10 –5  A/cm 2 ) and own an excellent UV-blocking property (almost block the whole UV light). Graphical abstract

Vaccines have a history that started late in the 18th century. From the late 19th century, vaccines could be developed in the laboratory. However, in the 20th century, it became possible to develop vaccines based on immunologie markers. In the 21st century, molecular biology permits vaccine development that was not possible before.

Using the Federal Bureau of Investigation’s Law Enforcement Officers Killed and Assaulted Program (LEOKA), this article examines law enforcement officers feloniously killed in the line of duty from 2002–2017 in which 821 officers were feloniously killed. Through an analysis of contextual and situational factors of the officer’s fatality, this article explores the extent to which body armor impacts the manner in which an officer is feloniously killed. Prior research has not sufficiently explored the effectiveness of body armor usage to reduce the risk of death of felonious killings. Results indicate that LEOs killed not wearing body armor were no more likely to suffer their fatality from somewhere besides their head compared to officers who were wearing body armor. Although there was no statistically significant difference, body armor and protective gear are a crucial part of an officer's work which has been further heightened during this recent era of social, political and civil unrest. The need for better protection for police officers needs to be prioritized.

In this paper, the thermal conductivity values of metals such as pure titanium, pure niobium, pure tungsten, iron, carbon steel (Q235, Q45), brass (H59), and purple copper (T2) were investigated in the temperature range of 273 K — 473 K. The experimental results showed that the repeatability of the thermal conductivity tests was better than 6% for all metals except for copper, where the repeatability was 10%. The test repeatability error increases with increasing temperature and is better than 3% for titanium, 45-gauge steel, and niobium (thermal conductivity below 50 W/m/K).

HighlightsThe hierarchical porous structure is regulated by various species of PVP to achieve impedance matching.Interfacial engineering boosts conductivity and constructs a multiband (C, X, Ku) tunable electromagnetic wave absorber.Hierarchical porous molybdenum selenide/epoxy coating exhibits marine anticorrosion capability.Electromagnetic wave (EMW) absorbing materials have an irreplaceable position in the field of military stealth as well as in the field of electromagnetic pollution control. And in order to cope with the complex electromagnetic environment, the design of multifunctional and multiband high efficiency EMW absorbers remains a tremendous challenge. In this work, we designed a three-dimensional porous structure via the salt melt synthesis strategy to optimize the impedance matching of the absorber. Also, through interfacial engineering, a molybdenum carbide transition layer was introduced between the molybdenum selenide nanoparticles and the three-dimensional porous carbon matrix to improve the absorption behavior of the absorber. The analysis indicates that the number and components of the heterogeneous interfaces have a significant impact on the EMW absorption performance of the absorber due to mechanisms such as interfacial polarization and conduction loss introduced by interfacial engineering. Wherein, the prepared MoSe2/MoC/PNC composites showed excellent EMW absorption performance in C, X, and Ku bands, especially exhibiting a reflection loss of − 59.09 dB and an effective absorption bandwidth of 6.96 GHz at 1.9 mm. The coordination between structure and components endows the absorber with strong absorption, broad bandwidth, thin thickness, and multi-frequency absorption characteristics. Remarkably, it can effectively reinforce the marine anticorrosion property of the epoxy resin coating on Q235 steel substrate. This study contributes to a deeper understanding of the relationship between interfacial engineering and the performance of EMW absorbers, and provides a reference for the design of multifunctional, multiband EMW absorption materials.

Metal aluminum is usually used to deoxidize as a deoxidant in RH reactor for producing ultra-low carbon Al-killed steel. Studying the process of aluminum deoxidization is of significance for forecasting the distribution of aluminum and optimization of deoxidization duration. An inhomogeneous two-phase model is used to simulate the RH circulating process. A multicomponent equation is used to simulate the diffuse process of elements, aluminum and oxygen. The control of the source term of the component equation is used to simulate the reaction process. Then the numerical model of aluminum deoxidization for producing ultra-low carbon Al-killed steel is established. The following results are concluded: the results of the simulation are accorded with the results of actual production. So the model is authentic and veracious. When the flux of lift gas is 96 Nm 3 /h, the mass fraction of oxygen is exhausted to balance concentration about 200 s after aluminum is thrown into liquid steel. Then the reaction stops. The element aluminum is uniform about 500 s after aluminum is thrown into liquid steel. The maximum value of the mass fraction of aluminum decreases from 0.14% to 0.12% and the time of deoxidization decreases from 179.2 s to 149.4 s while the flux of lift gas increases from 72 Nm 3 /h to 120 Nm 3 /h.

Distribution equipment is a critical component of the power distribution network. During long-term service, they are susceptible to corrosion, which degrades structural reliability and can ultimately threaten the operational reliability of the power grid. Current inspection practices rely primarily on visual assessment and sampling-based measurements, which are time-consuming, highly subjective, and unable to provide rapid on-site quantitative evaluation. Corrosion images can directly capture surface morphological changes induced by corrosion, and different corrosion severities correspond to distinct surface characteristics. In this study, surface images of Q235 steel under various corrosion levels were obtained through accelerated corrosion tests. A 2D convolutional neural network (2D-CNN) classification model was developed to enable automatic identification and accurate assessment of corrosion severity. The proposed model achieves a test set classification accuracy exceeding 97%, as confirmed by the experiments. These findings provide an intelligent and rapid approach for field inspection, helping inspectors efficiently determine corrosion severity and offering technical support for the secure operation of the power grid.