Integral Properties Research Articles

Cation-π Interactions Based Conductive Hydrogels with Slide-Ring Structure Toward Super Long-Time in-air/Underwater Linear Sensing and Communication.

Conductive hydrogels (CHs) are attracted more attention in the flexible wearable sensors field, however, how to stably apply CHs underwater is still a big challenge. In order to achieve the usage of CHs in aquatic environments, the integrated properties such as water retention ability, resistance to swelling, toughness, adhesiveness, linear GF sensing, and long-term usage are necessary to consider, but rarely reported in the previous reports. This paper proposes CHs prepared using cationic and aromatic monomers along with polyrotaxanes-based crosslinkers. Due to the intermolecular cation-π interactions and topological slide-ring-based polyrotaxanes, the CHs exhibit good mechanical performance, adhesive nature, and anti-swelling properties. The presence of slide-ring-based topological architecture effectively mitigates stress concentration. Additionally, the encapsulation of PA allows CHs to maintain functionality even after 240 days of direct placement at room temperature. Notably, the designed CHs exhibit linear sensitivity in detecting land/underwater human motions, and serve as Morse code signal transmitters for information transmission. Thus, the designed CHs may have broad applications in the underwater wearable sensors field.

Comprehensive analysis of cutting temperature, tool wear, surface integrity and tribological properties in sustainable milling of Ti6Al4V alloy: LN2, nanofluid and hybrid machining

Despite being expensive and difficult to process, the Ti6Al4V alloy is a vital component for crucial industries. To improve its machinability and accomplish sustainable production, environmentally friendly cooling and lubricating agencies are used. Studies on the machinability of the alloy are still necessary because of its unique features and significance in vital industries like aerospace, defense, and medicine. Therefore, this investigation focuses on tool wear, temperature, and surface integrity for sustainable milling Ti6Al4V under various machining environments, i.e., dry, pure-MQL, LN2, hBN, CuO-doped nanofluids, and hybrid methods. The produced nanofluids' thermophysical and rheological characteristics were examined in the study's initial phase. Because of the results from the first stage, machining performance indicators were assessed in the subsequent milling experiments. As a result, CuO-doped nanofluids gave improved results in terms of viscosity and pH. The best results obtained in the LN2 + CuO hybrid cooling lubrication environment in important machinability outcomes such as tool wear and surface integrity were attributed to the rheological properties of CuO-doped nanofluid and its harmonious cooperation with LN2-cryogenic cooling.

Using Symmetries to Investigate the Complete Integrability, Solitary Wave Solutions and Solitons of the Gardner Equation

In this paper, using a scaling symmetry, it is shown how to compute polynomial conservation laws, generalized symmetries, recursion operators, Lax pairs, and bilinear forms of polynomial nonlinear partial differential equations, thereby establishing their complete integrability. The Gardner equation is chosen as the key example, as it comprises both the Korteweg–de Vries and modified Korteweg–de Vries equations. The Gardner and Miura transformations, which connect these equations, are also computed using the concept of scaling homogeneity. Exact solitary wave solutions and solitons of the Gardner equation are derived using Hirota’s method and other direct methods. The nature of these solutions depends on the sign of the cubic term in the Gardner equation and the underlying mKdV equation. It is shown that flat (table-top) waves of large amplitude only occur when the sign of the cubic nonlinearity is negative (defocusing case), whereas the focusing Gardner equation has standard elastically colliding solitons. This paper’s aim is to provide a review of the integrability properties and solutions of the Gardner equation and to illustrate the applicability of the scaling symmetry approach. The methods and algorithms used in this paper have been implemented in Mathematica, but can be adapted for major computer algebra systems.

Varying linear polarisation in the dust-free gamma-ray burst 210610B

Context. Long gamma-ray bursts (GRBs) are produced by the collapse of some very massive stars, that emit ultra-relativistic jets. When the jets collide with the interstellar medium they decelerate and generate the so-called afterglow emission, which has been observed to be polarised. Aims. We study the polarimetric evolution of the GRB 210610B afterglow, at z = 1.1341. This allows us to evaluate the role of geometric and/or magnetic mechanisms in the GRB afterglow polarisation. Methods. We observed GRB 210610B using imaging polarimetry with CAFOS on the 2.2 m Calar Alto Telescope and FORS2 on the 4 × 8.1 m Very Large Telescope. Complementary optical spectroscopy was obtained with OSIRIS on the 10.4 m Gran Telescopio Canarias. We studied the GRB light-curve from X-rays to the optical bands and the Spectral Energy Distribution (SED). This allowed us to strongly constrain the line-of-sight extinction. Finally, we studied the GRB host galaxy using optical to NIR data to fit the SED and derive its integrated properties. Results. GRB 210610B had a bright afterglow with a negligible line-of-sight extinction. Polarimetry was obtained at three epochs: during an early plateau phase, at the time when the light curve breaks, and after the light curve steepened. We observe an initial polarisation of ∼4% that goes to zero at the time of the break, and it then again increases to ∼2%, with a change in the position angle of 54 ± 9 deg. The spectrum shows features with very low equivalent widths. This indicate a small amount of material in the line of sight within the host. Conclusions. The lack of dust and the low amount of material in the line of sight to GRB 210610B allowed us to study the intrinsic polarisation of the GRB optical afterglow. The GRB polarisation signals are consistent with ordered magnetic fields in refreshed shock or/and hydrodynamics-scale turbulent fields in the forward shock.

Existence of time-periodic strong solutions to the Navier-Stokes equation in the whole space

In this paper, the existence of time-periodic strong solutions to the Navier-Stokes equation in Rn is established under a suitable smallness condition on the external force. Our analysis is based on splitting periodic solutions into steady and purely periodic parts. One advantage of this decomposition is the availability of slightly more regularity in time of the purely periodic part. We apply this property to construct time-periodic solutions of the Navier-Stokes equation with information on the classes of their steady and purely periodic parts. It is also shown that the small solution v constructed in our existence theorem is unique within a class of time-periodic, not necessarily small, solutions having the same integrability properties as v.

Experimental study on multiple self-healing and impact properties of 2D carbon fiber fabric-reinforced epoxy composites with shape memory properties

Fiber-reinforced thermoset polymers are widely used in aerospace as a material with excellent performance. However, for the low-velocity impact damage to which they are most susceptible, existing repair methods are difficult to maintain the aerodynamic performance of the components (back to its pre-damage shape) after repair. In this study, the multiple impact deformation recovery, internal damage healing, and post-repair impact properties of epoxy-PCL (ε-caprolactone) 2D carbon fiber fabric-reinforced polymers with shape memory and self-healing properties were investigated. The material is manufactured using a hot press tank-prepreg process, curing at 160 degrees for 3.5 hours at 6 atmospheres. The results show that the incorporation of thermoplastic PCL into the composite matrix can enhance the self-healing ability and impact resistance of the material. Composites after lower energy impacts retain their structural integrity and mechanical properties after healing. Materials can recover effectively from a single impact, but repeated impacts can lead to more extensive damage, which makes healing more difficult and causes a decrease in Healing efficiency. The shape memory effect of composites can restore plastic deformation caused by impact, which highlights the potential of shape memory smart composites for aerospace applications.

Structural and covariance network alterations of the hippocampus and amygdala in congenital hearing loss children

ObjectiveThe hippocampus and amygdala, as important components of the limbic system, play crucial roles in central remodeling in congenital hearing loss. This study aimed to investigate the morphological integrity and network properties of the subfields of hippocampus and amygdala in children with congenital hearing loss. MethodsA total of 24 children with congenital hearing loss and 17 age- and sex- matched healthy controls (HC) are included in the study. T1-weighted images are analyzed by segmenting the brain into cortical and subcortical regions. Intergroup difference of volumes were explored. Structural covariance networks for the whole brain and hippocampus-amygdala subregions were constructed. Between-group differences of network property are investigated by comparing area under a range of network sparsity. ResultsPatients with congenital hearing loss exhibited significantly larger volumes in the right dentate gyrus and CA3 of the hippocampus. However, there were no significant differences in total hippocampal or showed decreased global efficiency and increased characteristic path length, indicating reduced network integration. Lower betweenness centrality was observed in the left hippocampal fissure in the hearing loss group. The changes in volume and network topological properties are not affected by age and sex. ConclusionChildren with congenital hearing loss display specific volumetric increases in hippocampal subregions, suggesting compensatory adaptations to auditory deprivation. The hippocampus-amygdala network shows significant reorganization, potentially underpinning cognitive and behavioral development issues associated with congenital hearing loss. These findings highlight the importance of targeted neural substrates in understanding and addressing the developmental challenges faced by children with congenital hearing loss.

Effect of spray-drying or fermentation on the solubility and carbohydrate profile of chickpea hydrolysates for beverage formulation

Powder beverage bases were developed using extruded and hydrolyzed chickpea supernatant through freeze-drying. This study evaluated the effects of spray-drying and adjuvant incorporation for producing powders and supernatant fermentation with LAB strains prior freeze-drying on the carbohydrate composition, structural integrity, and physical properties of chickpea beverage base powders. All powders had low insoluble (<0.2%) and soluble (<3%) dietary fiber contents due to processing. Starch content decreased below 9.49% when using adjuvants and 10.61% during fermentation. Both treatments also reduce raffinose oligosaccharide content below 6.1 mM/100 g. Spray-drying and adjuvant addition promoted a more amorphous starch structure, enhancing solubility, while fermentation induced more crystallinity, according to FTIR data. Microscopy showed small particle clusters and lack of birefringence. SEM images revealed starch granule damage from both fermentation and spray-drying, with more uniform particles in spray-dried powders. Spray-drying resulted in the smallest particle sizes (455-457 nm) and higher absolute zeta potential (8.12-9.51), indicating greater stability. Fermentation had the opposite effect, negatively impacting the colloidal system stability. Samples had a pH close to 6, except fermented powders with a pH of 3.6, affecting colloidal stability. Fermentation significantly reduced solubility but without practical implications, as all samples had solubility values over 93%, which is desirable for beverage-based powders. Spray-drying and fermentation altered the carbohydrate profile and structure of the powders. Fermentation prior producing powders may provide benefits, but it slightly decreases the system stability. Spray-drying can be used instead of freeze-drying to produce stable chickpea base powders that are highly soluble.

Improved stomatognathic model for highly realistic finite element analysis of temporomandibular joint biomechanics

BackgroundMechanical response analysis of the temporomandibular joint (TMJ) is crucial for understanding the occurrence and development of diseases. However, the realistic modeling of the TMJ remains challenging because of its complex composition and multivariate associations. ObjectiveThis study aims to develop a highly realistic stomatognathic model that accurately represents the geometric accuracy, structural integrity, and material properties. And further optimizes the interference and establishes the application range of the simplifications and the assumptions. MethodsGeometric reconstruction of the bone was based on high-resolution image data, with the accuracy of the occlusal surface ensured by plaster cast model registration. Soft tissues such as cartilage, the disc, the periodontal ligament (PDL), and disc attachments often need to be approximated or assumed. Therefore, the finite element methods (FEM) was used to optimize these assumptions, including 1) the biomechanical effects of the thickness and modulus of the PDL, 2) the approximation of the geometry and material behavior of the disc, and 3) the simplification of the loading and boundary conditions. Results1) The deformation of the PDL causes tooth movement, which spreads to the distal condyle and further effects the TMJ load situation, 2) Disc reconstructed by MRI and hyperelastic material behavior are necessary for accurate TMJ loading analyses, 3) The loss of relative sliding movement between teeth interferes with realistic TMJ loading. ConclusionThe improved stomatognathic model delivers highly realistic and validated simulation, offering theoretical guidance for virtual treatments and TMJ multivariate overload studies.

Graphene nanocoating on titanium maintains structural and antibiofilm properties post-sterilization

ObjectiveTo evaluate the impact of sterilization methods on the structural integrity and antimicrobial properties of graphene nanocoating on titanium (GN). MethodsGN was transferred to titanium using wet (WT) or dry transfer (DT) techniques and sterilized using an autoclave (AC), glutaraldehyde (GA), or ethylene oxide (EtO). The GN structure was characterized using Raman spectroscopy before and after sterilization. Additional specimens were characterized by Raman after AC and water jetting. Biofilm formation was assessed before and after AC using colony-forming units (CFU), biofilm biomass, and SEM (uncoated titanium was the control). Three independent samples were used for structural characterization and biofilm quantification. Statistical analyses were conducted using one-way analysis of variance (ANOVA) and Tukey's test (α = 0.05). ResultsWT and DT demonstrated high structural stability after sterilization and water jetting, with negligible coating quality or coverage loss. GN exhibited lower biofilm formation even after AC sterilization, as shown by the reduction in CFU counts, biofilm biomass, and SEM images compared to the control. SignificanceGN demonstrated high resistance to the stresses imposed by all sterilization methods tested, maintaining its structural integrity, resistance to water-jet cleaning, and antibiofilm potential. The findings suggest that standard industrial practices can effectively sterilize highly resilient GN on titanium implants and possibly other biomaterials.

Conservative deep neural networks for modeling competition of ribosomes with extended length

We develop a network model that combines several ribosome flow models with extended objects (RFMEO) competing for the finite pool of ribosomes. This alleviates the need to systematically coarse-grain the mRNA molecules. The dynamics of the network is described by a system of non-linear ordinary differential equations. It is shown that the network always converges to a steady state for a fixed number of ribosomes. Our analysis shows that increasing any of the transition rates along an RFMEO increases its output rate and either the output rates of the other RFMEOs all increase or all decrease. Simulations also demonstrate a counterintuitive result that increasing the ribosomal footprint may sometimes lead to an increase in the network production rate. Next, we propose a conservative deep neural network (CDNN) framework to approximate the solution of the network. The proposed loss function also incorporates the term satisfying the first integral property of the network. Point-wise comparison of the solutions by CDNN is in good agreement with the Runge–Kutta based numerical solution. Also, the CDNN framework offers a closed-form solution of the RFMEONP as a function of free parameters, thus allowing evaluation of the solution at any parameter value without again simulating the system.

Computational Thinking Processes in Solving the Corona Epidemic Model: Pre-service Maths Teachers

In the 21st century, pre-service mathematics teachers are expected to have problem-solving skills that are effective, efficient, and solutive and are in line with the mindset of computer experts. In learning mathematics, the concept of computational thinking (CT) is also needed and at this time, many still have difficulty solving mathematical problems in general, especially in solving problems in epidemic mathematical models. The subjects of this study were twenty-seven pre-service mathematics teacher students who took mathematical modeling courses. The researcher used the purposive sampling technique to select two research samples. The research method used was a descriptive qualitative research method in exploring the thinking process of pre-service mathematics teacher students in solving the problem of modeling the epidemic spread of disease. The results showed that the thinking process of the first subject began with identifying the problem and existing information by writing down the data in the form of a graph so as to get a certain pattern, which was then used as the basis for the process of transforming the problem into mathematical language. By adding assumptions related to the existence of environmental limitations in the next epidemic model, the concept of differential equations, in which there are integral properties and natural logarithms, can be used to find the solution to the epidemic model. The second subject was unable to solve the integral at hand. The researcher discovered that pre-service mathematics teacher students who correctly solved the problem in the mathematical model used CT components, namely decomposition, abstraction, pattern recognition, algorithm and mathematical literacy.

Sulforaphane acts through the NFE2L2/AMPK signaling pathway to protect boar spermatozoa from cryoinjury by activating antioxidant defenses

During cryopreservation, a substantial portion of spermatozoa undergoes apoptosis due to cryoinjury, resulting in decreased fertility. Boar spermatozoa are highly sensitive to temperature, with low temperature triggering reactive oxygen species (ROS) generation, leading to oxidative stress and apoptosis. Sulforaphane (SFN), a potent natural compound found in cruciferous vegetables, is efficacious in mitigating oxidative stress. We here supplemented different SFN concentrations (0, 1.25, 2.5, 5, 10, and 20 μM) into the freezing extender to explore its effect on boar sperm during cryopreservation and determine the optimal SFN concentration. Supplementation of 5 μM SFN exhibited the highest sperm motility, motion performance, plasma membrane integrity, acrosome integrity, and antioxidant properties (total antioxidant capacity (T-AOC) and antioxidant enzyme activity) after freezing and thawing. Then, RT group, C group and C + SFN group were established to explore the effect of SFN on the cryopreservation-induced sperm apoptosis level and fertilizing capacity of post-thawed sperms. SFN effectively rescued the apoptosis and fertilizing capacity of post-thawed sperms. Mechanistically, SFN activated the redox-sensitive nuclear factor erythroid 2-related factor 2 (NRF2/NFE2L2) by promoting adenosine monophosphate-activated protein kinase (AMPK) phosphorylation. This activation improved antioxidant defenses, ultimately improving cryoinjury in boar spermatozoa. In summary, SFN suppressed cryopreservation-induced apoptosis of spermatozoa by activating antioxidant defenses and the AMPK/NFE2L2 signaling pathway. These findings suggest a novel approach for augmenting the cryoprotective efficiency and spermatozoa fertility after cryopreservation.

Tailoring the size and shape of PbWO4 particles in highly filled polymer fibers for γ‐rays shielding

AbstractHighly filled polymer fibers offer huge promise for radiation protection safety and wear comfort of personal protective equipment (PPE) in radiation environments. However, it usually sacrifices mechanical properties that directly related to practical usability. Here, as high as 75 wt% PbWO4 (PWO) particles have been filled in polyvinyl alcohol (PVA) fiber via tailoring their size and shape for enhanced γ‐rays shielding and good mechanical properties. Clearly shown that 0 dimensional (0‐D) PWO exhibits better dispersion and compatibility between the interfaces than 1‐D PWO in highly filled PVA fibers. In addition, 70 wt% 0‐D PWO/PVA fibers display better mechanical properties than 70 wt% 1‐D PWO/PVA fibers. Note that 75 wt% 0‐D PWO/PVA fibers show 1.02 cN/dtex of tensile strength. However, 75 wt% 1‐D PWO/PVA fibers fail to be fabricated smoothly. Importantly, the overlapped fabrics with 75 wt% 0‐D PWO/PVA fibers display 43.05% of γ‐ray shielding (105 keV) meanwhile it offers good air and water vapor permeability for wear comfort. The superior γ‐ray shielding ascribes the polymer fibers with the higher filling in comparison with its counterpart, which provides a practical means to design radiation protection safety and wear comfort of articles.Highlights This work breaks the upper limit of filling in polymer fibers Filler structure can weigh the integrated properties of polymer fibers. 0‐D PWO particles promote interfacial compatibility in highly filled fibers. Radiation protection safety and wear comfort of articles tend to be designed.

Study of directions of unification of technology transfer in ukraine with the regulation of the European Union

Problem setting. In modern economic conditions, the key to effective economic development of any country is the development of the production sphere of the national economy. At the same time, its level depends on the penetration of knowledge-intensive, advanced and breakthrough technologies. Most economically developed countries even implement integrated state policies aimed at stimulating and scaling technology transfer processes. Thanks to this, the number of those technologies that are implemented in the sphere of public production increases, and the share of highly competitive products increases significantly. The economic system of Ukraine is no exception to this rule. Thus, since 2006, Ukraine has had a special official document the Law of Ukraine “On State Regulation of Activities in the Field of Technology Transfer”. Its main task is to determine the requirements of how the state (in the form of authorized bodies) will contribute to the scaling process of technology transfer. The course announced by Ukraine for joining the European Union (hereinafter referred to as “the EU”) imposes on it special obligations regarding the unification of regulatory approaches to the identification of technology transfer with EU requirements. The specified situation determines, on the one hand, the relevance of scientific research on this topic, and places on scientists the task of forming relevant proposals. It is science that should shape them and determine effective directions, methods and forms of unification of the principles of functioning of Ukraine with EU requirements and thereby stabilize and intensify the transfer of technologies. Purpose of research is to develop methods and techniques for unifying the regulatory approach to defining the essence of technology transfer in Ukraine with the requirements of the European Union. This will make it possible to formulate recommendations for the Ukrainian public authorities when they implement managerial decisions within the framework of the State technology policy and form the basis for proposals for amending its national regulatory acts. To achieve this goal, it is necessary to solve the following interrelated tasks: (1) to analyze the state of regulatory support for technology transfer under EU law; (2) to study the state of regulatory support for technology transfer under Ukrainian law; (3) to formulate proposals on the main directions of unification of legal regulation of technology transfer under Ukrainian law with the requirements of EU law. Analysis of recent research and publications. An analysis of recent research and publications on the topic shows that many scholars have considered the general issues of state intervention in the national economy. The problem of the essence of technology transfer has been studied both at the level of independent economic systems and within international organizational entities. Article’s main body. The object of this research is a set of regulatory methods and techniques for determining the content and essence of such a category as technology transfer. Both the requirements of Ukraine and the regulatory approaches of the European Union are studied. The analysis and generalization of the existing world and international approaches to the identification of the essence of technology transfer established that they are not unified among themselves and differ significantly from each other. It has been proven that this does not meet the needs of technology transfer participants and does not meet the strategic goals of Ukraine’s development. The expediency of expanding the existing concept of determining the essence of technology transfer defined in Ukraine is substantiated. Recommendations on directions for the unification of regulatory approaches to the definition of technology transfer with the European Union have been formed. The need to amend the provisions of the Law of Ukraine “On State Regulation of Activities in the Field of Technology Transfer” in order to bring it into line with the requirements of the European Union has been proven. Conclusions and prospects for development. It was determined that the current legislation of Ukraine contains a narrower approach to determining the essence of technology transfer. Recommendations on the unification of the requirements of Ukraine with the requirements of the EU, on the issue of identification of technology transfer, have been formed. The expediency of expanding the forms of technology transfer is substantiated by supplementing them with the following: – Transfer of technology during the implementation of special interstate defense and industrial programs. – Transfer of technology within the framework of grant funding and cooperation. – Transfer of technology during the implementation of public procurement. – Transfer of technology as a contribution to the integral property complex (statutory or accumulated capital) of economic entities. – Transfer of technology during the creation of startups.

Reactions of Ru3(CO)12 with 1,5-bis(diphenylphosphino)pentane: Synthesis, characterization, crystal structure, Hirshfeld surface and QTAIM Analysis of Ru3(CO)10(µ-dpppe)

Reactions of Ru3(CO)12 with 1,5-bis(diphenylphosphino)pentane (dpppe) in THF induced by sodium benzophenone ketyl radical anion, resulted in the expected metal cluster [Ru3(CO)11]2(µ-dpppe) (1) and Ru3(CO)10(µ-dpppe) (2) as the main products. Clusters 1 and 2 were characterized by spectroscopic methods, including Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (1H and 31P{1H} NMR).The structural features were determined using single crystal X-ray diffraction analysis. In cluster 1 and 2, the (dpppe) links two trinuclear cluster units via phosphine moieties and bridges to Ru–Ru bond, respectively. Both clusters were stabilized by the presence of C–H⋯O interactions and were further analyzed by Hirshfeld surface analysis. The bonding interactions within cluster 2 were studied using the Quantum Theory of Atoms in Molecules (QTAIM). Various local and integral topological properties of the electron density were calculated, along with the source function (SF) calculations and electron localization function (ELF) analysis.

The phenomenon of viral chromosomal integration

The literature review is devoted to the chromosomally integrating viruses, the integration property. These are revealed using modern diagnostic methods, including highthroughput sequencing. The review describes various types of viruses, such as retroviruses, adenoviruses, herpes viruses, papillomaviruses, hepatitis B, SARS-CoV-2 and others. These viruses have the ability to integrate their genomes into the host cell genomes and their prevalence. Modern information on the molecular mechanisms of viral integration and methods of differential diagnostics is presented. Each of these viruses has its own unique ways of interacting with the host cell genome to maintain a latent state, which determines the specifics of the infectious process and pathological consequences for the body due to the possibility of effective reactivation.

The Role of Chitosan and Gelatin-Based Scaffolds in Bone Regeneration: A Systematic Review.

Guided bone regeneration facilitates the growth of new bone in areas where there is a bone defect or insufficiency. This technique involves placing a barrier membrane over the bone graft site, and the membrane prevents the invasion of soft tissue (such as gingival tissue) into the bone graft area. This allows the slower-growing bone cells to populate the area without competition, promoting proper bone regeneration. When combined, chitosan and gelatin create composite scaffolds that leverage the strengths of both materials. Chitosan provides structural integrity and antimicrobial properties, and gelatin enhances cell attachment and proliferation, which improves mechanical properties and makes it more suitable for supporting bone regeneration in load-bearing areas.This systematic review aims to evaluate the effectiveness ofchitosan and gelatin-based scaffolds in bone regeneration. Various databases such as PubMed, Cochrane Library, LILAC, and Google Scholar were screened to adhere to the eligibility criteria. The included studies in the review were the in vivo and in vitro assessment of the chitosan and gelatin efficiency as a scaffold. Six studies were investigated for the involvement of chitosan and gelatin-based scaffolds in bone regeneration. Of these, two in vivostudies examined bone regeneration by measuring alkaline phosphatase activity (ALP) using different staining techniques, while the remaining four in vitro studies used histologic and histometric analysis where stem cells, chemicals, and other biopolymers were compared. Chitosan and gelatin scaffolds consistently showed better results in terms of bone repair throughout all six experiments. Gelatin's capacity for regeneration can be increased by mixing itwith chitosan. For additional advancement, future researchers need to focus on incorporating biopolymers.The potential of scaffolds composed of gelatin and chitosan to replace tissue lost due to periodontitis shows great clinical significance.

Enhancing geometric integrity and surface hardness of SLM-printed Ti-6Al-4V components with support structures and laser nitriding

This study investigated the effect of support structure and post-processing surface nitriding on high aspect ratio Ti-6Al-4V components fabricated using Selective Laser Melting (SLM). It examined changes in geometric integrity, porosity, and mechanical properties. Samples were printed without support structures (S1) and with support structures (S2). After SLM printing, both samples underwent open-air laser nitriding at duty cycles (DC) ranging from 50 % to 100 %, aiming to create crack-free nitride layers to increase surface hardness. The results indicated that support structures effectively mitigate thermal-induced deformation, with S2 exhibiting minimal warping and closer adherence to design specifications than S1. Although S2 showed increased porosity as revealed by X-ray Computed Tomography (XCT), its refined microstructure contributed to increased hardness. Optical Microscope and Scanning Electron Microscope (SEM) analyses demonstrated that laser nitriding at a 50 % duty cycle produced uniform, crack-free titanium nitride (TiN) layers. Vickers hardness tests revealed a significant enhancement in the surface hardness of both laser-nitrided samples, with S2 displaying finer TiN dendrites that further improved its surface hardness. The use of support structures was found to be effective in achieving a more uniform microstructure and enhanced hardness in the nitride layer.

Milky Way and Andromeda analogues from the TNG50 simulation

ABSTRACT We present the properties of Milky Way- and Andromeda-like (MW/M31-like) galaxies simulated within TNG50, the highest resolution run of the IllustrisTNG suite of lambda-cold dark matter magnetohydrodynamical simulations. We introduce our fiducial selection for MW/M31 analogues, which we propose for direct usage as well as for reference in future analyses. TNG50 contains 198 MW/M31 analogues, that is, galaxies with stellar discy morphology, with a stellar mass in the range of $M_* = 10^{10.5 - 11.2}~\rm {\rm M}_{\odot }$, and within an MW-like 500 kpc-scale environment at $z=0$. These are resolved with baryonic (dark matter) mass resolution of $8.5\times 10^4\rm {\rm M}_{\odot }$ ($4.5\times 10^5\rm {\rm M}_{\odot }$) and $\sim 150$ pc of average gas spatial resolution in the star-forming regions. The majority of TNG50 MW/M31 analogues at $z=0$ exhibit a bar, 60 per cent are star-forming, the sample includes three Local Group-like systems, and a number of galaxies host one or more satellites as massive as, for example, the Magellanic Clouds. Even within such a relatively narrow selection, TNG50 reveals a great diversity in galaxy and halo properties, as well as in past histories. Within the TNG50 sample, it is possible to identify several simulated galaxies whose integral and structural properties are consistent, one or more at a time, with those measured for the Galaxy and Andromeda. With this paper, we document and release a series of broadly applicable data products that build upon the IllustrisTNG public release and aim to facilitate easy access and analysis by public users. These include datacubes across snapshots ($0 \le z \le 7$) for each TNG50 MW/M31-like galaxy, and a series of value-added catalogues.