In Situ Structure Characterization in Slot-Die-Printed All-Polymer Solar Cells with Efficiency Over 9%

Herein, high-performance printed all-polymer solar cells (all-PSCs) based on a bulk-heterojunction (BHJ) blend film are demonstrated using PTzBI as the donor and N2200 as the acceptor. A slot-die process is used to prepare the BHJ blend, which is a cost-effective, high-throughput approach to achieve large-area photovoltaic devices. The real-time crystallization of polymers in the film drying process is investigated by in situ grazing incidence wide-angle X-ray scattering characterization. Printing is found to significantly improve the crystallinity of the polymer blend in comparison with spin coating. Moreover, printing with 1,8-diiodooctane as the solvent additive enhances the polymer aggregation and crystallization during solvent evaporation, eventually leading to multi-length-scale phase separation, with PTzBI-rich domains in-between the N2200 crystalline fibers. This unique morphology achieved by printing fabrication results in an impressively high power conversion efficiency of 9.10%, which is the highest efficiency reported for printed all-PSCs. These findings provide important guidelines for controlling film drying dynamics for processing all-PSCs

Noise bridges dynamical correlation and topology in coupled oscillator networks

We study the relationship between dynamical properties and interaction patterns in complex oscillator networks in the presence of noise. A striking finding is that noise leads to a general, one-to-one correspondence between the dynamical correlation and the connections among oscillators for a variety of node dynamics and network structures. The universal finding enables an accurate prediction of the full network topology based solely on measuring the dynamical correlation. The power of the method for network inference is demonstrated by the high success rate in identifying links for distinct dynamics on both model and real-life networks. The method can have potential applications in various fields due to its generality, high accuracy and efficiency.Comment: 2 figures, 2 tables. Accepted by Physical Review Letter

Depth resolution of Piezoresponse force microscopy

Given that a ferroelectric domain is generally a three dimensional entity, the determination of its area as well as its depth is mandatory for full characterization. Piezoresponse force microscopy (PFM) is known for its ability to map the lateral dimensions of ferroelectric domains with high accuracy. However, no depth profile information has been readily available so far. Here, we have used ferroelectric domains of known depth profile to determine the dependence of the PFM response on the depth of the domain, and thus effectively the depth resolution of PFM detection

Hysteresis in the quantum Hall regimes in electron double quantum well structures

We present in this paper experimental results on the transport hysteresis in electron double quantum well structures. Exploring the measurement technique of fixing the magnetic field and sweeping a front gate voltage (Vg), we are able to study the hysteresis by varying the top layer Landau level fillings while maintaining a relatively constant filling factor in the bottom layer, allowing us to tackle the question of the sign of Rxx(up)-Rxx(down), where Rxx(up) is the magnetoresistance when Vg is swept up and Rxx(down) when Vg swept down. Furthermore, we observe that hysteresis is generally stronger in the even integer quantum Hall effect (IQHE) regime than in the odd-IQHE regime. This, we argue, is due to a larger energy gap for an even-IQHE state, determined by the Landau level separation, than that for an odd-IQHE state, determined by the Zeeman splitting

Solving the Dirac equation with nonlocal potential by Imaginary Time Step method

The Imaginary Time Step (ITS) method is applied to solve the Dirac equation with the nonlocal potential in coordinate space by the ITS evolution for the corresponding Schr\"odinger-like equation for the upper component. It is demonstrated that the ITS evolution can be equivalently performed for the Schr\"odinger-like equation with or without localization. The latter algorithm is recommended in the application for the reason of simplicity and efficiency. The feasibility and reliability of this algorithm are also illustrated by taking the nucleus $^{16}$O as an example, where the same results as the shooting method for the Dirac equation with localized effective potentials are obtained

Subcellular localization of Bombyx mori ribosomal protein S3a and effect of its over-expression on BmNPV infection

In the present study, using a BV/PH-Bms3a-EGFP, we found that Bombyx mori ribosomal protein S3a (BmS3a) with EGFP fused to its C-terminal, was predominantly localized in the cytoplasm of B. mori cells. Subsequently, to investigate the effect of BmS3a over-expression on BmNPV infection both at the cellular level and in vivo, a transgenic BmN cell line expressing BmS3a was constructed using a piggybac-A3-EGFP and recombinant baculovirues expressing BmS3a-EGFP fusion protein (BV/IE1-Bms3a-EGFP) or EGFP (BV/EGFP) were produced using BmNPV/Bac-to-Bac expression system. Results showed that the number of polyhedral in the transgenic cells of BmS3a was much smaller than that in non-transgenic cells, and that silkworms injected with BV/IE1-Bms3a-EGFP survived much longer than those injected with BV/EGFP. Taken together, we speculated that BmS3a might be capable of inhibiting BmNPV replication through its activities in the cytoplasm

Immunocompromised individuals are at increased risk of COVID‐19 breakthrough infection, hospitalization, and death in the post‐vaccination era:A systematic review

Introduction: Immunocompromised individuals have been shown to mount a reduced response to vaccination, resulting in reduced vaccine effectiveness in this cohort. Therefore, in the postvaccination era, immunocompromised individuals remain at high risk of breakthrough infection and COVID‐19 related hospitalization and death, which persist despite vaccination efforts. There has been a marked paucity of systematic reviews evaluating existing data describing the clinical measures of efficacy of COVID‐19 vaccination, specifically in immunocompromised populations. In particular, there is a scarcity of comprehensive evaluations exploring breakthrough infections and severe COVID‐19 in this patient population. Methods: To address this gap, we conducted a systematic review which aimed to provide a summary of current clinical evidence of the effectiveness of COVID‐19 vaccination in the immunocompromised population. Using PRISMA guidelines, we conducted a literature search on PubMed and the Cochrane database published between January 1, 2021 to September 1, 2022. Results: Our findings demonstrated that despite vaccination, immunocompromised patients remained at high risk of new breakthrough COVID‐19 infection and severe COVID‐19 outcomes compared to the general population. We found increased average relative risk (RR) of breakthrough infections in the immunocompromised population, including patients with cancer (RR = 1.4), HIV (RR = 1.92), chronic kidney disease (RR = 2.26), immunodeficiency (RR = 2.55), and organ transplant recipients (RR = 6.94). These patients are also at greater risk for hospitalizations and death following COVID‐19 breakthrough infection. We found that the RR of hospitalization and death in Cancer patients was 1.08 and 2.82, respectively. Conclusion: This demonstrated that vaccination does not offer an adequate level of protection in these groups, necessitating further measures such as Evusheld and further boosters

Properties of Resonating-Valence-Bond Spin Liquids and Critical Dimer Models

We use Monte Carlo simulations to study properties of Anderson's resonating-valence-bond (RVB) spin-liquid state on the square lattice (i.e., the equal superposition of all pairing of spins into nearest-neighbor singlet pairs) and compare with the classical dimer model (CDM). The latter system also corresponds to the ground state of the Rokhsar-Kivelson quantum dimer model at its critical point. We find that although spin-spin correlations decay exponentially in the RVB, four-spin valence-bond-solid (VBS) correlations are critical, qualitatively like the well-known dimer-dimer correlations of the CDM, but decaying more slowly (as $1/r^a$ with $a \approx 1.20$, compared with $a=2$ for the CDM). We also compute the distribution of monomer (defect) pair separations, which decay by a larger exponent in the RVB than in the CDM. We further study both models in their different winding number sectors and evaluate the relative weights of different sectors. Like the CDM, all the observed RVB behaviors can be understood in the framework of a mapping to a "height" model characterized by a gradient-squared stiffness constant $K$. Four independent measurements consistently show a value $K_{RVB} \approx 1.6 K_{CDM}$, with the same kinds of numerical evaluations of $K_{CDM}$ give results in agreement with the rigorously known value $K_{CDM}=\pi/16$. The background of a nonzero winding number gradient $W/L$ introduces spatial anisotropies and an increase in the effective K, both of which can be understood as a consequence of anharmonic terms in the height-model free energy, which are of relevance to the recently proposed scenario of "Cantor deconfinement" in extended quantum dimer models. We also study ensembles in which fourth-neighbor (bipartite) bonds are allowed, at a density controlled by a tunable fugacity, resulting (as expected) in a smooth reduction of K.Comment: 26 pages, 21 figures. v3: final versio