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In this paper, we designed double V-shaped Al/Ni multilayer energy-containing microdevices with different V-angles, and we performed finite element modeling and simulation of the heat transfer process of the designed energy-containing microdevice. Temperature-dependent resistivity was introduced to effectively simulate the phase change during ignition. We simulated the temperature and current density distribution in the central region of the Al/Ni multilayer energy-containing microdevice and predicted the ignition voltage threshold for the specific device structure. Al/Ni multilayer energy-containing microdevices with different V-angles were prepared by electron beam evaporation technology, and ignition experiments on the prepared devices under the excitation of 47 μF capacitance were conducted. The experimental results show that the critical voltage of ignition increases with the increase in the V-angle, which verifies the correctness of the proposed finite element model. [ABSTRACT FROM AUTHOR]

Background: Previous research demonstrates that adopting, abandoning, and re-adopting (i.e., cycling) a healthy dietary pattern (HDP) improved, reverted, and re-improved cardiovascular disease (CVD) risk factors. In addition, changes in CVD risk factors are associated with dietary modifications of gut microbiota. Objective: We sought to assess the effects of cycling an HDP on gut microbiota and CVD risk factors. Methods: Retrospectively, we used data from a randomized controlled, crossover trial with three 3-week controlled dietary interventions, each separated by a 5-week period of participant-chosen, uncontrolled food intake. Seventeen participants (10 males, 7 females, age 26 ± 4 years old, BMI 23 ± 3 kg/m2) all consumed intervention diets that followed healthy U.S.-style dietary patterns. Gut microbiota composition and cardiovascular risk factors were measured before and after each HDP. Results: Repeatedly adopting and abandoning an HDP led to a cycling pattern of changes in the gut microbial community and taxonomic composition. During the HDP cycles, relative abundances of several bacterial taxa (e.g., Collinsella, Mediterraneibacter, Romboutsia, and Dorea) decreased and returned to baseline repeatedly. Similar HDP cycling occurred for multiple CVD risk factors (i.e., serum total cholesterol and LDL-C concentrations). Consistent negative associations were observed between changes in Mediterraneibacter or Collinsella and serum total cholesterol/HDL-C ratio. Conclusions: These results support previous findings that HDP cycling affected multiple CVD risk factors and expand the HDP cycling phenomenon to include several bacterial taxa. Young adults are encouraged to adopt and sustain a healthy dietary pattern to improve cardiovascular health, potentially through modifying gut microbiota composition. [ABSTRACT FROM AUTHOR]

The discovery of polar metals challenges long‐standing assumptions about the incompatibility between polar order and metallicity. However, despite recent progress, the mechanism allowing the coexistence of these supposedly forbidden properties remains unclear. Herein, carriers are introduced by constructing a symmetric polar/nonpolar interface in the KNbO3/BaTiO3 (KNO/BTO) superlattice (SL), enabling the coexistence of ferroelectric and metallic properties. A first‐principles analysis of the evolution of polar distortion and metallicity in the KNO/BTO SL under biaxial strain in the face to explore the dependence of the two at the microscopic level is performed. It is found that compressive strain enhances polarization distortion while reducing conductivity from three dimensions to two dimensions, indicating a weak coupling mechanism between carriers and polarization. Furthermore, it is shown that the presence of holes strengthens the TiO (NbO) covalent bonds, resulting in an unexpected enhancement of the polarization properties of the KNO/BTO SL. Therefore, it is proposed using the carrier screening effect and covalent bonding synergies as a framework for understanding the interaction between ferroelectricity and free carriers, rather than just a single factor therein. These results provide new theoretical insights for designing robust polar metals in perovskite ferroelectrics. [ABSTRACT FROM AUTHOR]

Throughout infancy, changes in growth and development are observed, including changes in nutritional requirements; at approximately 6 months of age, when complementary feeding begins, breastmilk and/or formula are no longer the sole source of energy and nutrients. Little is known about the impact of complementary feeding (CF) approaches used during this time on infant nutrition and growth. Baby-led weaning (BLW) has continued to gain popularity over the last two decades, emphasizing the importance of examining the adequacy of different CF methods. This narrative review of 19 studies from January 2010 to April 2024 aims to discuss the differences between BLW and conventional weaning (CW). The definition of BLW varied across studies, and no standard definition has been established. Though no differences in energy were reported, macronutrient and micronutrient intakes were variable between approaches, including for micronutrients such as iron and zinc. Of the few studies with growth data, results comparing BLW and CW were conflicting. Differences were seen in the demographics of parents who chose to follow BLW and breastfeeding prevalence and duration prior to complementary feeding. Additional research is needed to understand the impacts of BLW and CW on nutrient intakes and growth to inform recommendations for infant complementary feeding approaches. [ABSTRACT FROM AUTHOR]

Oxygen vacancies play a crucial role in stabilizing the ferroelectric phase in hafnium (Hf) oxide-based thin films and in shaping the evolution of their ferroelectric properties. In this study, we directly manipulated the oxygen vacancy concentration in Hf0.5Zr0.5O2−x (HZO) ferroelectric thin films in situ using oxygen plasma treatment. We scrutinized the variations in the ferroelectric properties of HZO films across different oxygen vacancy concentrations by integrating the findings from ferroelectric performance tests. Additionally, we elucidated the mechanism underlying the influence of oxygen vacancies on the coercive field and polarization properties of HZO ferroelectric films through the first-principles density functional theory (DFT) calculations. Finally, to study the impact of oxygen vacancies on the practical application of HZO ferroelectric synaptic devices, leveraging the plasticity of the ferroelectric polarization, we constructed a multilayer perceptron (MLP) network. We simulated its recognition accuracy and convergence speed under different oxygen vacancy concentrations in the MNIST recognition task. [ABSTRACT FROM AUTHOR]

Resistive random access memory (RRAM) holds great promise for in-memory computing, which is considered the most promising strategy for solving the von Neumann bottleneck. However, there are still significant problems in its application due to the non-uniform performance of RRAM devices. In this work, a bilayer dielectric layer memristor was designed based on the difference in the Gibbs free energy of the oxide. We fabricated Au/Ta2O5/HfO2/Ta/Pt (S3) devices with excellent uniformity. Compared with Au/HfO2/Pt (S1) and Au/Ta2O5/Pt (S2) devices, the S3 device has a low reset voltage fluctuation of 2.44%, and the resistive coefficients of variation are 13.12% and 3.84% in HRS and LRS, respectively, over 200 cycles. Otherwise, the bilayer device has better linearity and more conductance states in multi-state regulation. At the same time, we analyze the physical mechanism of the bilayer device and provide a physical model of ion migration. This work provides a new idea for designing and fabricating resistive devices with stable performance. [ABSTRACT FROM AUTHOR]