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One of the main approaches to inhibit carrier cooling in semiconductor systems enabling the study of hot carrier solar cell protocols is the use of concentrated illumination to obtain high power densities and create a phonon bottleneck. This, however, typically also increases the lattice temperature of the solar cells significantly. Accordingly, the solar cells subject to high concentration illumination also need to withstand high operating temperatures. Having previously demonstrated the high temperature tolerance of the triple halide perovskite (FA0.8Cs0.2Pb1.02I2.4Br0.6Cl0.02) solar cells, here the hot carrier relaxation dynamics are studied in these devices using high power transient absorption (TA) measurements. In addition to monitoring TA spectra obtained at different time delays, the thermalization mechanisms of hot carriers is mapped with power dependent TA to extract the carrier cooling time in this system under in-operando conditions at various bias conditions that reflect the Jsc, Vmax and Voc of these structures, and subsequently deconvolve the underlying physics of carrier relaxation; as well as track the dynamics of the thermalization close to working conditions of the solar cells. These measurements uncover a complex interaction of hot carrier thermalization involving the temporal carrier density, transport, and extraction, and apparent non-equivalent contributions with respect to non-equilibrium photogenerated electrons and holes in these metal halide perovskite solar cell architectures.

Introduction Speech is an integral component of human communication, requiring the coordinated efforts of various organs to produce sound (Titze & Alipour, 2006). The glottis region, a key player in voice production, assumes a crucial role in this intricate process. As air, emanating from the lungs in a confined space, interacts with the vocal folds (VFs) within the human body, it gives rise to the creation of voice (Alipour & Vigmostad, 2012). Understanding the mechanical intricacies of this process is very important. Studying VFs in vivo situations is hard work. However, the orientation, shape and size of VFs fibers have been extracted with synchrotron X-ray microtomography. (Bailly et al., 2018) The investigation of mechanical properties of both human and animal VFs has been carried out through various methodologies in the literature. The mechanical properties of VFs have been studied using the uniaxial extension test (Alipour & Vigmostad, 2012) assuming a linear behavior, while the nonlinearity and anisotropy of VFs has been determined using a multiscale method as in Miri et al. (2013). Pipette aspiration has also been used to extract in vivo elastic properties of VFs (Scheible et al., 2023). Mechanical behavior of VFs layers in tension, compression and shear has been studied. (Cochereau et al., 2020). Fluid-structure interaction (FSI) simulations provide a valuable tool to gain a deeper understanding of voice production (Ghorbani et al. 2022). These simulations allow us to model the dynamic interplay between the VFs and air. Our research focuses on investigating the mechanical properties of canine vocal folds and utilizing these findings in an FSI simulation. Through this simulation, we aim to unravel how these mechanical properties affect voice production.Methods To investigate the mechanical properties of canine VFs, an in vitro study was conducted involving 6 mixedbreed dogs. The samples were harvested from canine cadavers euthanized for reasons unrelated to this study. In the following, the VFs were harvested and tested upon 3-4 hours post-animal sacrifice. Experimental trials were carried out using the STM-1 device (SANTAM Co.), equipped with a 100 kg load cell. Seven uniaxial tensile tests were done on each sample, with displacement rates of 1, 5, 10, 20, 40, 60, and 120 mm/min. The very slow rate of 1 mm/min was chosen to assess only elastic properties eliminating viscosity effects. Various hyperelastic models were used to fit the experimental data. Subsequently, for each model, both the mean and standard deviation (SD) were determined for the hyperelastic model parameters and their residuals. For FSI analysis we used a simplified laryngeal model as a hollow cylinder with a diameter of 50 mm and a thickness of 3 mm. The overall length of the larynx was set at 100 mm. The VFs were modeled as a circular disc with a small elliptical fissure in the midst of the cylinder section. Boundary conditions were established based on pressure differentials, with the inlet gauge pressure set at 1200 Pa and the relative pressure at the outlet set to 0. To account for the turbulent nature of airflow within the larynx, we employed the K-epsilon method to solve the motion differential equations in a two-way fluid-structure interaction simulation using ANSYS FLUENT 2021. This approach enabled us to investigate how the acquired mechanical properties of canine vocal folds affect the FSI simulations during phonation, resulting in a more comprehensive understanding of their impact. To determine the vibrational frequency of VFs, we calculated the time it took to reach maximum displacement and then quadrupled this value to obtain the period of vibration.

Let $G$ be a graph on $n$ nodes with algebraic connectivity $\lambda_{2}$. The eccentricity of a node is defined as the length of a longest shortest path starting at that node. If $s_\ell$ denotes the number of nodes of eccentricity at most $\ell$, then for $\ell \ge 2$, $$\lambda_{2} \ge \frac{ 4 \, s_\ell }{ (\ell-2+\frac{4}{n}) \, n^2 }.$$ As a corollary, if $d$ denotes the diameter of $G$, then $$\lambda_{2} \ge \frac{ 4 }{ (d-2+\frac{4}{n}) \, n }.$$ It is also shown that $$\lambda_{2} \ge \frac{ s_\ell }{ 1+ \ell \left(e(G^{\ell})-m\right) },$$ where $m$ and $e(G^\ell)$ denote the number of edges in $G$ and in the $\ell$-th power of $ G $, respectively.

While task-agnostic debiasing provides notable generalizability and reduced reliance on downstream data, its impact on language modeling ability and the risk of relearning social biases from downstream task-specific data remain as the two most significant challenges when debiasing Pretrained Language Models (PLMs). The impact on language modeling ability can be alleviated given a high-quality and long-contextualized debiasing corpus, but there remains a deficiency in understanding the specifics of relearning biases. We empirically ascertain that the effectiveness of task-agnostic debiasing hinges on the quantitative bias level of both the task-specific data used for downstream applications and the debiased model. We empirically show that the lower bound of the bias level of the downstream fine-tuned model can be approximated by the bias level of the debiased model, in most practical cases. To gain more in-depth understanding about how the parameters of PLMs change during fine-tuning due to the forgetting issue of PLMs, we propose a novel framework which can Propagate Socially-fair Debiasing to Downstream Fine-tuning, ProSocialTuning. Our proposed framework can push the fine-tuned model to approach the bias lower bound during downstream fine-tuning, indicating that the ineffectiveness of debiasing can be alleviated by overcoming the forgetting issue through regularizing successfully debiased attention heads based on the PLMs' bias levels from stages of pretraining and debiasing.

We consider modal logic extended with the well-known temporal operator `eventually' and provide a cut-elimination procedure for a cyclic sequent calculus that captures this fragment. The work showcases an adaptation of the reductive cut-elimination method to cyclic calculi. Notably, the proposed algorithm applies to a cyclic proof and directly outputs a cyclic cut-free proof without appealing to intermediate machinery for regularising the end proof.

We explore the theory of illfounded and cyclic proofs for the propositional {modal $\mu$-calculus}. A fine analysis of {provability} for classical and intuitionistic modal logic provides a novel bridge between finitary, cyclic and illfounded conceptions of proof and re-enforces the importance of two normal form theorems for the logic: guardedness and disjunctiveness.

The presence of hot carriers is presented in the operational properties of an (FA,Cs)Pb(I, Br, Cl)3 solar cell at ambient temperatures and under practical solar concentration. At 100 K, clear evidence of hot carriers is observed in both the high energy tail of the photoluminescence spectra and from the appearance of a non-equilibrium photocurrent at higher fluence in light J-V measurements. At room temperature, however, the presence of hot carriers in the emission at elevated laser fluence are shown to compete with a gradual red shift in the PL peak energy as photo induced halide segregation begins to occur at higher lattice temperature. The effects of thermionic emission of hot carriers and the presence of a non-equilibrium carrier distribution are also shown to be distinct from simple lattice heating. This results in large unsaturated photocurrents at high powers as the Fermi distribution exceeds that of the heterointerface controlling carrier transport and rectification.