Search Results (127)

The primary objective of any conservation breeding program is to preserve the genetic diversity of populations. This objective is a persistent challenge, especially in small populations which are prone to loss of heterozygosity. In this study, we proposed a novel parent-selection strategy aimed at the long-term maintenance of high levels of genetic diversity. Our approach is based on estimating the Probability of Offspring Heterozygosity (POH)—the likelihood that a mating will produce heterozygous offspring—using SNP genotype data. This strategy was evaluated through computer simulations, where parental pairs with the highest POH values were preferentially selected to produce the next generation. Simulations explored the effects of varying the number of breeding pairs, and the number of unlinked SNP markers. Selection based on POH resulted in observed heterozygosity (H_OBS) consistently exceeding expected heterozygosity (H_EXP), a trend that was sustained for up to 1000 generations. While further evaluation is needed within more complex population genetic frameworks—accounting for linkage disequilibrium, recombination, optimal contribution, and phenotypic selection—our findings highlight the potential of POH as a valuable tool for enhancing genetic diversity in conservation breeding programs. Full article

Rosavin, a glycoside isolated from Rhodiola rosea, exhibits various biological activities, including potential modulation of metabolic pathways. Despite promising findings in animal models, its effects on many human bone cells remain unexplored. This study aimed to investigate, for the first time, the in vitro effects of rosavin on human osteoblasts (HOBs), focusing on BMP-2 expression, cell morphology, and culture confluence as indicators of osteogenic activity. HOB cultures were treated with 50 µM or 100 µM rosavin for 21 days. BMP-2 expression was measured by ELISA, collagen production was assessed via Sirius Red staining, and cell morphology and confluence were evaluated using phase-contrast microscopy. A significant increase in BMP-2 expression was observed in the 100 µM rosavin group compared to the mineralization control (p < 0.05), particularly on days 14 and 21. Both rosavin-treated groups exhibited higher confluence than controls, with the 50 µM group showing unexpectedly greater confluence than the 100 µM group. Rosavin at 50 µM also promoted a cuboidal morphology characteristic of active HOBs. The presence of collagen validated both the successful progression of the mineralization process and the correct implementation of the experimental protocol. Rosavin enhances BMP-2 expression and supports HOB proliferation and morphological maturation in vitro. These findings suggest its potential as a supportive agent in the prevention or treatment of metabolic bone diseases. Further research is necessary to determine its bioavailability, safety profile, and therapeutic relevance in clinical settings. Full article

The increasing demand for induction hobs necessitates efficient cooling systems to ensure the safe operation of electronic cut-outs. This study investigates the thermal representation of three different ignition designs integrated into an induction hob cooling system. A simplified model consisting of a radial fan, a daughterboard, and the electronics installed in the systems is used for the maintenance of the system. Remote measurements of air velocities at the cooler outlets are compared with the results obtained through programmable system dynamics (CFD) operations using FloEFD v2021.1 software. The findings of the study using the k-ε turbulence model show that Type 1 temperature is resistant to the lowest surface temperature for both the closest (IGBT 1) and the farthest (IGBT 2) temperature to the fan. Conversely, Type 3 temperatures exhibited high temperatures. Air velocity comparisons showed a maximum error rate of 30%, which is acceptable considering the variability in Type 1. Measurement system evaluation and DOE study were continued to increase the experimental range. This study demonstrates the utility offered by heatsink design in optimizing the cooling system of induction hobs and provides valuable insights for integrating thermal management systems. Full article

Frustrated magnetic systems arising in geometrically constrained lattices represent rich platforms for exploring unconventional phases of matter, including fractional magnetization plateaus, incommensurate orders and complex domain dynamics. However, determining the microscopic spin configurations that stabilize such phases is a key challenge, especially when in-plane and out-of-plane spin components coexist and compete. Here, we combine neutron scattering and magnetic susceptibility experiments with simulations to investigate the emergence of field-induced fractional plateaus and the related criticality in a frustrated magnet holmium tetraboride (HoB₄) that represents the family of rare earth tetraborides that crystalize in a Shastry–Sutherland lattice in the $ab$ plane. We focus on the interplay between classical and quantum criticality near phase boundaries, as well as the role of material defects in the stabilization of the ordered phases. We find that simulations using classical annealing can explain certain observed features in the experimental Laue diffraction and the origin of multiple magnetization plateaus. Our results show that defects and out-of-plane interactions play an important role and can guide the route towards resolving microscopic spin textures in highly frustrated magnets. Full article

We report on the arc melt syntheses of HoB₂ and Nb-substituted HoB₂ polycrystalline ingots and their magnetocaloric and microstructural properties. XRD data and microstructural analysis reveal that a nominal 10% Nb addition during synthesis results in changes to unit cell parameters and grain morphology. Interpretation of the refined cell parameters using Vegard’s law shows that Nb substitutes into HoB₂ with stoichiometry Ho_0.93Nb_0.07B₂. Arc-melted products are polycrystalline bulk samples containing minor phases such as Ho₂O₃, Ho, and HoB₄. Nb substitution results in a smaller grain size (~sub-micron) and a higher Curie temperature, T_C, compared to HoB₂. With a 10 T applied field, the maximum magnetic entropy, ΔS_M, for HoB₂ and for Ho_0.93Nb_0.07B₂, is 46.8 Jkg⁻¹K⁻¹ and 38.2 Jkg⁻¹K⁻¹ at 18 K and 21 K, respectively. Both samples show second-order phase transitions. Despite high totals of minor phases (e.g., ~10 wt.% and ~25 wt.%), the calculated relative cooling powers are greater than 1300 Jkg⁻¹ and 600 Jkg⁻¹ at 10 T and 5 T, respectively. The magnetocaloric properties of both samples are consistent with Holmium boride compounds prepared via alternative methods. Full article

The wheel-side electric drive system is a melding of a vehicle powertrain and suspension system, which saves chassis space and can adapt to different models. To achieve the goal of highly modularized development, the system is supposed to meet the requirements of various working conditions without changing the interface state. The electric motor drives the wheel through two-stage fixed axis helical gears, so the transmission is short in path and acts as the suspension arm at the same time. As a result, the gears are critical to output robustness and NVH performance. The modeling accuracy is decisive for simulations and tests, so it is necessary to build a precise geometric model instead of the data-fitting estimation. The gears are manufactured by a hobbing and form grinding process, which is described functionally along with the relationship between the tooling parameters and tooth profile curves. Based on the rain flow methodology and extrapolation theory, a comprehensive load spectrum with nine stages is formulated, which can cover the working conditions of a basic version, a NVH version, and a durability version. According to the Miner cumulative damage hypothesis, the equivalent durability mileage of 150,000 km is converted. The prototype machine is simulated and verified on the test bench, and the test results show that the wheel-side electric drive system has a reliable output performance. The equivalent damage of the comprehensive load spectrum is 63.27%, where the 2# stage driving gear is the most vulnerable component of the whole system. The research in this paper can provide data support for damage calculation and lightweight optimization with modularized development and applications in the future. Full article

The ongoing transformation of district heating systems (DHSs) aims to reduce emissions and increase renewable energy sources. The objective of this work is to integrate solar thermal (ST) and seasonal aquifer thermal energy storage (ATES) in various scenarios applied to a large DHS. Mixed-integer linear programming (MILP) is used to develop a comprehensive model that minimizes operating costs, including heat pumps (HPs), combined heat and power (CHP) units, electric heat boilers (EHBs), heat-only boilers (HOBs), short-term thermal energy storage (TES), and ATES. Different ATES scenarios are compared to a reference without seasonal TES (potential of 15.3 GWh of ST). An ATES system with an injection well temperature of about 55 °C has an overall efficiency of 49.8% (58.6% with additional HPs) and increases the integrable amount of ST by 178% (42.5 GWh). For the scenario with an injection well temperature of 20 °C and HPs, the efficiency is 86.6% and ST is increased by 276% (57.5 GWh). The HOB heat supply is reduced by 8.9% up to 36.6%. However, the integration of an ATES is not always economically or environmentally beneficial. There is a high dependency on the configurations, prices, or emissions allocated to electricity procurement. Further research is of interest to investigate the sensitivity of the correlations and to apply a multi-objective MILP optimization. Full article

Cranio-maxillofacial bone reconstruction, especially for large defects, remains challenging. Synthetic biomimetic materials are emerging as alternatives to autogenous grafts. Tissue engineering aims to create natural tissue-mimicking materials, with calcium phosphate-based scaffolds showing promise for bone regeneration applications. This study developed a porous calcium metaphosphate (CMP) scaffold with physicochemical properties mimicking natural bone, aiming to create a prevascularized synthetic bone graft. The scaffold, fabricated using sintered monocalcium phosphate with poly (vinyl alcohol) as a porogen, exhibited pore sizes ranging from 0 to 400 μm, with the highest frequency between 80 and 100 μm. The co-culture of endothelial cells (ECs) with human alveolar osteoblasts (aHOBs) on the scaffold led to the formation of tube-like structures and intrinsic VEGF release, reaching 10,455.6 pg/mL This level approached the optimal dose for vascular formation. Conversely, the co-culture with mesenchymal stem cells did not yield similar results. Combining ECs and aHOBs in the CMP scaffold offers a promising approach to developing prevascularized grafts for cranio-maxillofacial reconstruction. This innovative strategy can potentially enhance vascularization in large tissue-engineered constructs, addressing a critical limitation in current bone regeneration techniques. The prevascularized synthetic bone graft developed in this study could significantly improve the success rate of maxillofacial reconstructions, offering a viable alternative to autogenous grafts. Full article

The accurate measurement of cooking vessel temperatures in induction hobs is crucial for ensuring optimal cooking performance and safety. To achieve this, improvements in existing measurement methods such as thermocouples, thermistors, and infrared (IR) temperature sensors are being explored. However, traditional IR sensors are sensitive to interference from the heated glass ceramic, severely affecting accuracy. This challenge is addressed by introducing a new sensor system with an optical filter designed to match the glass ceramic’s optical characteristics. The theoretical model presented here proposes the separation of the total radiation reaching the IR sensor into components emitted by the cooking vessel and the glass ceramic. However, the radiation component originating from the glass ceramic mentioned here is significantly higher than the radiation component of the cooking vessel, which creates difficulties in measuring the temperature of the cooking vessel. Simulations and real cooking experiments validate the model and demonstrate that the optic filter significantly increases the contribution of pot radiation to the sensor measurement. This causes a more accurate reflection of the actual cooking vessel temperature, leading to improved temperature control and enhanced cooking experiences in domestic induction hob appliances. This research contributes to the field by innovatively addressing challenges in real-time temperature control for induction cooking appliances. The elimination of pot dependence and improved accuracy have significant implications for cooking efficiency, safety and food quality. Full article

The article presents the results of research aimed at developing mathematical models for determining the components of grinding force occurring during the sharpening of the rake face of hob cutters. The development of the models was based on the results obtained during experimental tests conducted in the first stage of the research. The studies were carried out using a tool grinder and an aluminum oxide grinding wheel. During the tests, two components of the grinding force were measured, using a piezoelectric dynamometer. A sample made of HS6-5-2 high-speed steel was ground. Grinding was carried out using different sets of cutting parameters. Based on the obtained measurement results, two mathematical models were developed in the form of (1) a multiple regression function and (2) a polynomial function, enabling the calculation of the normal and the tangential force. The experimentally obtained results were then compared with those calculated based on the developed models, and the results of this comparison showed that the developed models provide a good basis for analyzing the sharpening process of hob cutters in terms of variable grinding parameters. Full article

In recent years, there has been a growing number of adult orthodontic patients with periodontal disease. The progression of periodontal disease is well-linked to oxidative stress (OS). Nevertheless, the impact of OS on orthodontic tooth movement (OTM) is not fully clarified. Therefore, we applied an OS in vitro-model utilizing H₂O₂ to study its effect on tension-induced mechanotransduction in human osteoblasts (hOBs). Experimental parameters were established based on cell viability and proliferation. Apoptosis detection was based on caspase-3/7 activity. Gene expression related to bone-remodeling (RUNX2, P2RX7, TNFRSF11B/OPG), inflammation (CXCL8/IL8, IL6, PTRGS2/COX2), autophagy (MAP1LC3A/LC3, BECN1), and apoptosis (CASP3, CASP8) was analyzed by RT-qPCR. IL6 and PGE2 secretion were determined by ELISA. Tension increased the expression of PTRGS2/COX2 in all groups, especially after stimulation with higher H₂O₂ concentration. This corresponds also to the measured PGE2 concentrations. CXCL8/IL8 was upregulated in all groups. Cells subjected to tension alone showed a general upregulation of osteogenic differentiation-related genes; however, pre-stimulation with OS did not induce significant changes especially towards downregulation. MAP1LC3A/LC3, BECN1 and CASP8 were generally upregulated in cells without OS pre-stimulation. Our results suggest that OS might have considerable impacts on cellular behavior during OTM. Full article

In recent years, the demand for orthopedic implants has surged due to increased life expectancy, necessitating the need for materials that better mimic the biomechanical properties of human bone. Traditional metal implants, despite their mechanical superiority and biocompatibility, often face challenges such as mismatched elastic modulus and ion release, leading to complications and implant failures. Polyetheretherketone (PEEK), a semi-crystalline polymer with an aromatic backbone, presents a promising alternative due to its adjustable elastic modulus and compatibility with bone tissue. This study explores the functionalization of sandblasted 3D-printed PEEK disks with the bioactive peptides Aoa-GBMP1α and Aoa-EAK to enhance human osteoblast response. Aoa-GBMP1α reproduces 48–69 trait of Bone Morphogenetic Protein 2 (BMP-2), whereas Aoa-EAK is a self-assembling peptide mimicking extracellular matrix (ECM) fibrous structure. Superficial characterization included X-ray photoelectron spectroscopy (XPS), white light interferometer analysis, static water contact angle (S-WCA), and force spectroscopy (AFM-FS). Biological assays demonstrated a significant increase in human osteoblast (HOB) proliferation, calcium deposition, and expression of osteogenic genes (RUNX2, SPP1, and VTN) on functionalized PEEK compared to non-functionalized controls. The findings suggest that dual peptide-functionalized PEEK holds significant potential for advancing orthopedic implant technology. Full article

This work demonstrates an enhancement mode heterojunction bipolar p-FET (HEB-PFET) structure with a AlGaN/GaN heterojunction bipolar transistor (HBT) integrated on the drain side. Such device design notably contributes to the ultra-high output current density, which is conventionally limited by the low hole mobility and concentration in the p-FETs. The HEB-PFET exhibits an output current density of 241 mA/mm, which is 134 times larger compared to the conventional p-FET (C-PFET) and 2.4 times of the homojunction bipolar p-FET (HOB-PFET). This can be attributed to a better current gain of HBT than homojunction bipolar transistor (BJT). An optimized HEB-PFET of 6 nm p-GaN layer beneath the gate is proposed, where I_ON/I_OFF is >10¹¹, and V_th is −0.44 V. Additionally, thermal stabilities are studied with temperature changes from 300 K to 425 K. Moreover, a semi-empirical compact model is presented to visually explain the working principle of the HEB-PFET. Full article

Background and Objectives: Temperature-sensitive (TS) mutants of TP53 are thermally unstable, unfolded, and inactive at body temperature but can be refolded and reactivated at sub-physiological temperatures. TS TP53 may be amenable for functional rescue by hypothermia or structure-stabilizing drugs, and may retain low-level transcriptional activity at 37 °C. TP53 mutations are observed in 47% of all esophageal cancers (ECs) and 25% to 40% of gastric cancers (GCs). We aimed to investigate the trends and outcomes of EC and GC with TS TP53 mutations using cBioportal. We hypothesize that TS TP53 mutants in EC and GC present a unique prognostic profile distinct from non-TS TP53 mutants, potentially affecting overall survival and cancer progression. Materials and Methods: We identified 1924 patients from cBioportal with GC or EC, harboring any TP53 mutation. Patients were then stratified based on the TP53 temperature sensitivity according to a recently reported functional analysis of its activity. Patients were also stratified based on a history of Barrett’s esophagus (BE), cancer stage, sex, and race. We then compared populations (TS vs. non-TS TP53) to assess differences and evaluated survival outcomes. Results: Males represented 77% of the cohort, and 51.6% of the samples were from patients with stage IV cancer. No association was found between TS vs. non-TS mutational status and BE, cancer stage, or race. Interestingly, a significantly higher proportion of females (22.9%) than males (14.5%) displayed a TS TP53 mutation (p = 0.012). No significant difference was seen in overall survival between the TS and non-TS mutations capable of ≥50% growth suppression at 32 °C (median = 33 vs. 28 months, p = 0.36). This trend was also observed when the patients were filtered based on cancer location. The median survival for EC was 32.5 months compared to 33 months (p = 0.67). In cases of GC, median survival times could not be determined due to the insufficient number of events. Conclusions: Although no statistical significance was observed, a decrease in overall survival for patients with TS TP53 mutations was noted. The result is counterintuitive given that TS mutants have less severe structural destabilization and suggests TS TP53 mutations may have a unique prognostic value that warrants further investigation. Full article

The rake angles on both sides of the cutting edges of the hourglass worm gear hob significantly influence its cutting performance, which, in turn, plays a decisive role in the surface quality of the machined worm wheel. To balance the rake angles along the tooth height direction of each hob tooth and enhance the overall cutting performance of the hob, this paper proposes a method that utilizes a rotating paraboloid surface to generate the helical rake face of the hourglass worm gear hob. First, the conjugate condition equations for the rake face generated by the rotating paraboloid surface are derived. A mathematical model for the helical rake face of planar double-enveloping hourglass worm gear hob is established. This study explores the influence of two machining parameters on the rake angle, specifically the milling drive ratio coefficient k and the geometric parameter of a parabolic milling cutter p. Through a systematic analysis of the variations in rake angle at the dividing toroidal surface and along the tooth height direction, the optimal parameter values were identified as k = 0.9115 and p = 0.6834. The results show that, after optimization, the hob rake angle range is around ±4.7°, with a maximum rake angle difference of 6.3072° along the tooth height direction, and the rake angles on both sides of the teeth are more balanced. The structure of the rake face is more reasonable, reflecting the feasibility of rotating paraboloid tools for forming tools in the machining of complex surfaces. Full article