Effect of electrical stress on time dependent dielectric breakdown (TDDB) tolerate capability of HfO2-ZrO2ferroelectric films with different thicknesses.

HfO2-based ferroelectric materials as the most promising candidate for the ferroelectric memories, have been widely studied for more than a decade due to their excellent ferroelectric properties and CMOS compatibility. In order to realize its industrialization as soon as possible, researchers have been devoted to improving the reliability performance, such as wake up, imprint, limited endurance, et al. Among them, the breakdown characteristic is one of main failure mechanisms of HfO2-based ferroelectric devices, which limits the write/read reliability of the devices. Based on this, we systematically studied the effect of thickness on the time-dependent dielectric breakdown (TDDB) tolerate capability of HfO2-ZrO2(HZO) FE films under both forward and reverse electrical stress conditions. The thickness of HZO FE film ranged from 6 to 20 nm. Our findings reveal that decreasing the thickness of the HZO FE film leads to an improvement in TDDB tolerance capability which is attributed to the fact that higher density of oxygen vacancies in thinner HZO FE films can effectively inhibit the generation of new oxygen vacancies and the growth of conductive filaments, thus effectively improving the TDDB characteristics. These results provide a potential solution for mitigating breakdown characteristics of HfO2-based ferroelectric devices in memory applications.

Impact of Combined Modulation of Two Potassium Ion Currents on Spiral Waves and Turbulent States in the Heart.

In the realm of cardiac research, the control of spiral waves and turbulent states has been a persistent focus for scholars. Among various avenues of investigation, the modulation of ion currents represents a crucial direction. It has been proved that the methods involving combined control of currents are superior to singular approaches. While previous studies have proposed some combination strategies, further reinforcement and supplementation are required, particularly in the context of controlling arrhythmias through the combined regulation of two potassium ion currents. This study employs the Luo-Rudy phase I cardiac model, modulating the maximum conductance of the time-dependent potassium current and the time-independent potassium current, to investigate the effects of this combined modulation on spiral waves and turbulent states. Numerical simulation results indicate that, compared to modulating a single current, combining reductions in the conductance of two potassium ion currents can rapidly control spiral waves and turbulent states in a short duration. This implies that employing blockers for both potassium ion currents concurrently represents a more efficient control strategy. The control outcomes of this study represent a novel and effective combination for antiarrhythmic interventions, offering potential avenues for new antiarrhythmic drug targets.

Correlation between Serum Magnesium Level and Cardiac Valve Calcification in Patients with Chronic Kidney Disease.

BACKGROUND: The aim of the study was to investigate the correlation between serum magnesium (Mg) level and cardiac valve calcification (CVC) in patients with chronic kidney disease (CKD). METHODS: A total of 232 CKD patients hospitalized from August 2016 to December 2020 were divided into CVC and non-CVC groups. Their clinical data and laboratory examination results were compared, the risk factors for CVC in CKD patients were explored using logistic regression analysis, and Spearman's method was used to analyze the correlation between serum Mg level and CVC degree. According to the tertiles of mean serum Mg level, they were assigned into low serum Mg group (≤ 0.96 mmol/L), middle serum Mg group (0.97 - 1.07 mmol/L), and high serum Mg group (≥ 1.08 mmol/L). The relationship of serum Mg level with CVC risk in CKD patients was analyzed through the Cox regression model, and a prediction model was established using independent risk factors. RESULTS: Long CKD duration, low serum Mg level, high serum phosphorus (P) level, and high CKD stage were independent risk factors for CVC. Serum Mg level was significantly negatively correlated with the severity of CVC (r = -0.743, p < 0.05). The risk of CVC was significantly higher in low serum Mg group than that in high serum Mg group [hazard ratio (HR) = 2.852, 95% confidence interval (CI): 1.325 - 6.432, p = 0.005]. A CVC prediction model was established based on independent risk factors as follows: CVC predictive value = EXP [0.491 - 0.546 (CKD duration) - 0.454 (serum P level) + 2.145 (serum Mg level) - 0.812 (CKD stage)]/1 + EXP [0.491 - 0.546 (CKD duration) - 0.454 (serum P level) + 2.145 (serum Mg level) - 0.812 (CKD stage)]. The area under curve of the model was 0.750 (95% CI: 0.822 - 0.965), and that of the CVC prediction model for CKD patients in test set was 0.774 (95% CI: 0.761 - 0.975), showing no significant difference from that in training set (p > 0.05). CONCLUSIONS: Low serum Mg level serves as an independent risk factor for CVC in CKD patients, and may increase the risk of CVC. Therefore, the serum Mg level in CKD patients should be corrected timely in clinical practice.

Regeneration of large bone defects using mesoporous silica coated magnetic nanoparticles during distraction osteogenesis.

Distraction osteogenesis (DO) represents an effective but undesirably lengthy treatment for large bone defects. Both magnetic nanoparticles and silicon have been shown to induce osteogenic differentiation of mesenchymal stem cells (MSCs), the key participant in bone regeneration. We herein synthesized mesoporous silica coated magnetic (Fe3O4) nanoparticles (M-MSNs) and evaluated its potential for acceleration of bone regeneration in a rat DO model. The M-MSNs exhibited good biocompatibility and remarkable capability in promoting the osteogenic differentiation of MSCs via the canonical Wnt/ß-catenin pathway in vitro. More importantly, local injection of M-MSNs dramatically accelerated bone regeneration in a rat DO model according to the results of X-ray imaging, micro-CT, mechanical testing, histological examination, and immunochemical analysis. This study demonstrates the notable potential of M-MSNs in promoting bone regeneration during DO by enhancing the osteogenic differentiation of MSCs, paving the way for clinical translation of M-MSNs in DO to repair large bone defects.

Spoof surface plasmon polaritons based on ultrathin corrugated metallic grooves at terahertz frequency.

We investigate the dispersion properties of an ultrathin spoof plasmonic waveguide based on metal strip grooves using the finite element method. The confinement ability of the surface plasmon polariton (SPP) waves are influenced by the dispersion curves, which can be modulated by the structure parameters. The propagation characteristics of a subwavelength planar plasmonic waveguide ring resonator have also been studied. Furthermore, a gain medium is introduced to compensate for the propagation loss of the SPP wave in the device at terahertz frequency. It is demonstrated that the gain medium provides an enhancement for the control of on/off states of the signal with the presence of pumping, which paves a way for gain-assisted switching and lasing applications in the terahertz regime.

Theoretical analysis of performance enhancement in GeSn/SiGeSn light-emitting diode enabled by Si3N4 liner stressor technique.

We comprehensively investigate the energy band diagrams, carrier distribution, spontaneous emission rate rsp, and the internal quantum efficiency ηIQE in the lattice-matched GeSn/SiGeSn double heterostructure light-emitting diode (LED) wrapped in a Si3N4 liner stressor. The large tensile strain introduced into the device by the expansion of the Si3N4 liner is characterized by numerical simulation. A lower Sn composition required for the indirect to direct bandgap transition and a higher ratio of the electron occupation probability in the Γ conduction valley are achieved in the tensile strained GeSn/SiGeSn LED in comparison with the relaxed device. Analytical calculation shows that the tensile strained LED wrapped in the Si3N4 liner stressor exhibits the improved rsp and ηIQE compared to the relaxed device. rsp and ηIQE also can be enhanced by increasing Sn composition, carrier injection density, and n-type doping concentration in the GeSn active layer.

MRI/SPECT/Fluorescent Tri-Modal Probe for Evaluating the Homing and Therapeutic Efficacy of Transplanted Mesenchymal Stem Cells in a Rat Ischemic Stroke Model.

Quantitatively tracking engraftment of intracerebrally or intravenously transplanted stem cells and evaluating their concomitant therapeutic efficacy for stroke has been a challenge in the field of stem cell therapy. In this study, first, an MRI/SPECT/fluorescent tri-modal probe (125I-fSiO4@SPIOs) is synthesized for quantitatively tracking mesenchymal stem cells (MSCs) transplanted intracerebrally or intravenously into stroke rats, and then the therapeutic efficacy of MSCs delivered by both routes and the possible mechanism of the therapy are evaluated. It is demonstrated that (125)I-fSiO4@SPIOs have high efficiency for labeling MSCs without affecting their viability, differentiation, and proliferation capacity, and found that 35% of intracerebrally injected MSCs migrate along the corpus callosum to the lesion area, while 90% of intravenously injected MSCs remain trapped in the lung at 14 days after MSC transplantation. However, neurobehavioral outcomes are significantly improved in both transplantation groups, which are accompanied by increases of vascular endothelial growth factor, basic fibroblast growth factor, and tissue inhibitor of metalloproteinases-3 in blood, lung, and brain tissue (p < 0.05). The study demonstrates that 125I-fSiO4@SPIOs are robust probe for long-term tracking of MSCs in the treatment of ischemic brain and MSCs delivered via both routes improve neurobehavioral outcomes in ischemic rats.

Simulation investigation of tensile strained GeSn fin photodetector with Si(3)N(4) liner stressor for extension of absorption wavelength.

In this paper, we design a biaxial tensile strained GeSn photodetector with fin structure wrapped in Si(3)N(4) liner stressor. A large biaxial tensile strain is induced in GeSn fins by the expansion of Si(3)N(4) liner stressor. The distribution of tensile strain in GeSn fins was calculated by a finite element simulation. It is observed that magnitude of the strain increases with the reduction of fin thickness T(fin). Under the biaxial tensile strain, the direct band gap E(G,Γ) of GeSn fin photodetector is significantly reduced by lowering Γ conduction valley in energy and lifting of degeneracy of valence bands. As the 30 nm Si(3)N(4) liner stressor expanses by 1%, a E(G,Γ) reduction of ~0.14 eV is achieved in Ge(0.92)Sn(0.08) fins with a T(fin) of 100 nm. The cut-off wavelengths of strained Ge(0.96)Sn(0.04), Ge(0.92)Sn(0.08) and Ge(0.90)Sn(0.10) fin photodetectors with a T(fin) of 100 nm are extended to 2.4, 3.3, and 4 µm, respectively. GeSn fin photodetector integrated with Si(3)N(4) liner stressor provides an effective technique for extending the absorption edge of GeSn with Sn composition less than 10% to mid-infrared wavelength.

Theoretical investigation of tensile strained GeSn waveguide with Si3N4 liner stressor for mid-infrared detector and modulator applications.

We theoretically investigate a tensile strained GeSn waveguide integrated with Si3N4 liner stressor for the applications in mid-infrared (MIR) detector and modulator. A substantial tensile strain is induced in a 1 × 1 µm² GeSn waveguide by the expansion of 500 nm Si3N4 liner stressor and the contour plots of strain are simulated by the finite element simulation. Under the tensile strain, the direct bandgap E(G,Γ) of GeSn is significantly reduced by lowering the Γ conduction valley in energy and lifting of degeneracy of valence bands. Absorption coefficients of tensile strained GeSn waveguides with different Sn compositions are calculated. As the Si3N4 liner stressor expands by 1%, the cut-off wavelengths of tensile strained Ge(0.97)Sn(0.03), Ge(0.95)Sn(0.05), and Ge(0.90)Sn(0.10) waveguide photodetectors are extended to 2.32, 2.69, and 4.06 µm, respectively. Tensile strained Ge(0.90)Sn(0.10) waveguide electro-absorption modulator based on Franz-Keldysh (FK) effect is demonstrated in theory. External electric field dependence of cut-off wavelength and propagation loss of tensile strained Ge(0.90)Sn(0.10) waveguide is observed, due to the FK effect.

Recent Progress of Wide Bandgap Perovskites towards Two-Terminal Perovskite/Silicon Tandem Solar Cells.

Perovskite/silicon tandem solar cells have garnered considerable interest due to their potential to surpass the Shockley-Queisser limit of single-junction Si solar cells. The rapidly advanced efficiencies of perovskite/silicon tandem solar cells benefit from the significant improvements in perovskite technology. Beginning with the evolution of wide bandgap perovskite cells towards two-terminal (2T) perovskite/silicon tandem solar cells, this work concentrates on component engineering, additives, and interface modification of wide bandgap perovskite cells. Furthermore, the advancements in 2T perovskite/silicon tandem solar cells are presented, and the influence of the central interconnect layer and the Si cell on the progression of the tandem solar cells is emphasized. Finally, we discuss the challenges and obstacles associated with 2T perovskite/silicon tandem solar cells, conducting a thorough analysis and providing a prospect for their future.

A Compact Constraint Incremental Method for Random Weight Networks and Its Application.

Incremental random weight networks (IRWNs) face the issues of weak generalization and complicated network structure. There is an important reason: the learning parameters of IRWNs are determined in a random fashion without guidance, which may increase many redundant hidden nodes, and thereby leading to inferior performance. To resolve this issue, a novel IRWN with compact constraint that guides the assignment of random learning parameters (CCIRWN) is developed in this brief. Using the iteration method of Greville, a compact constraint that simultaneously assures the quality of generated hidden nodes and the convergence of the CCIRWN is built to perform learning parameter configuration. Meanwhile, the output weights of the CCIRWN are assessed analytically. Two types of learning methods for constructing the CCIRWN are proposed. Finally, the performance evaluation of the proposed CCIRWN is undertaken on the 1-D nonlinear function approximation, several real-world datasets, and data-driven estimation based on the industrial data. Numerical and industrial examples indicate that the proposed CCIRWN with compact structure can achieve favorable generalization ability.

pH-sensitive gold nanoclusters labeling with radiometallic nuclides for diagnosis and treatment of tumor.

The acidic microenvironment is one of the remarkable features of tumor and is also a reliable target for tumor theranostics. Ultrasmall gold nanoclusters (AuNCs) have good in vivo behaviors, such as non-retention in liver and spleen, renal clearance, and high tumor permeability, and held great potential for developing novel radiopharmaceuticals. Herein, we developed pH-sensitive ultrasmall gold nanoclusters by introducing quaternary ammonium group (TMA) or tertiary amine motifs (C6A) onto glutathione-coated AuNCs (TMA/GSH@AuNCs, C6A-GSH@AuNCs). Density functional theory simulation revealed that radiometal 89Sr, 223Ra, 44Sc, 90Y, 177Lu, 89Zr, 99mTc, 188Re, 106Rh, 64Cu, 68Ga, and 113Sn could stably dope into AuNCs. Both TMA/GSH@AuNCs and C6A-GSH@AuNCs could assemble into large clusters responding to mild acid condition, with C6A-GSH@AuNCs being more effective. To assess their performance for tumor detection and therapy, TMA/GSH@AuNCs and C6A-GSH@AuNCs were labeled with 68Ga, 64Cu, 89Zr and 89Sr, respectively. PET imaging of 4T1 tumor-bearing mice revealed TMA/GSH@AuNCs and C6A-GSH@AuNCs were mainly cleared through kidney, and C6A-GSH@AuNCs accumulated in tumors more efficiently. As a result, 89Sr-labeled C6A-GSH@AuNCs eradicated both the primary tumors and their lung metastases. Therefore, our study suggested that GSH-coated AuNCs held great promise for developing novel radiopharmaceuticals that specifically target the tumor acidic microenvironment for tumor diagnosis and treatments.

Cobalt-Doped Mesoporous Silica Coated Magnetic Nanoparticles Promoting Accelerated Bone Healing in Distraction Osteogenesis.

Introduction: Large bone abnormalities are commonly treated using distraction osteogenesis (DO), but it is not suitable for a long-term application; therefore, there is an urgent need for adjuvant therapy that can accelerate bone repair. Methods: We have synthesized mesoporous silica-coated magnetic nanoparticles doped with cobalt ions (Co-MMSNs) and assessed their capacity to quicken bone regrowth in a mouse model of DO. Furthermore, local injection of the Co-MMSNs significantly accelerated bone healing in DO, as demonstrated by X-ray imaging, micro-CT, mechanical tests, histological evaluation, and immunochemical analysis. Results: In vitro, the Co-MMSNs exhibited good biocompatibility and induced angiogenic gene expression and osteogenic development in bone mesenchymal stem cells. And the Co-MMSNs can promote bone regeneration in a rat DO model. Discussion: This study demonstrated the significant potential of Co-MMSNs to shorten the DO treatment duration and effectively reduce the incidence of complications.

Pure-Phase, Large-Grained Wide-Band-Gap Perovskite Films for High-Efficiency, Four-Terminal Perovskite/Silicon Tandem Solar Cells.

High-quality, stable perovskite films with a wide band gap between 1.65 and 1.80 eV are highly suitable for efficient and cost-competitive silicon-based tandem solar cells. Herein, we demonstrate that the combined strategies of the Pb(SCN)2 additive and air annealing can enable the Cs0.22FA0.78Pb(I0.85Br0.15)3 films with a wide band gap of 1.65 eV and favored properties including pure composition, high crystallinity, micro-sized grains, and reduced defects. With these desired films, the average efficiencies of semitransparent perovskite solar cells (PSCs) are boosted from (18.13 ± 0.31) to (20.35 ± 0.28)%. Further, the semitransparent PSC is used to assemble the four-terminal perovskite/TOPCon tandem solar cell. Benefiting from its excellent performance and preferred optical properties, the obtained tandem solar cell yields a milestone efficiency of 30.32%.

Black Phosphorus/MnO2 Nanocomposite Disrupting Bacterial Thermotolerance for Efficient Mild-Temperature Photothermal Therapy.

The emergence of multi-drug resistant (MDR) pathogens is a major public health concern, posing a substantial global economic burden. Photothermal therapy (PTT) at mild temperature presents a promising alternative to traditional antibiotics due to its biological safety and ability to circumvent drug resistance. However, the efficacy of mild PTT is limited by bacterial thermotolerance. Herein, a nanocomposite, BP@Mn-NC, comprising black phosphorus nanosheets and a manganese-based nanozyme (Mn-NZ) is developed, which possesses both photothermal and catalytic properties. Mn-NZ imparts glucose oxidase- and peroxidase-like properties to BP@Mn-NC, generating reactive oxygen species (ROS) that induce lipid peroxidation and malondialdehyde accumulation across the bacterial cell membrane. This process disrupts unprotected respiratory chain complexes exposed on the bacterial cell membrane, leading to a reduction in the intracellular adenosine triphosphate (ATP) content. Consequently, mild PTT mediated by BP@Mn-NC effectively eliminates MDR infections by specifically impairing bacterial thermotolerance because of the dependence of bacterial heat shock proteins (HSPs) on ATP molecules for their proper functioning. This study paves the way for the development of a novel photothermal strategy to eradicate MDR pathogens, which targets bacterial HSPs through ROS-mediated inhibition of bacterial respiratory chain activity.

Graded Heterojunction Improves Wide-Bandgap Perovskite for Highly Efficient 4-Terminal Perovskite/Silicon Tandem Solar Cells.

Wide-bandgap (WBG) perovskite solar cells (PSCs) are essential for highly efficient and stable silicon/perovskite tandem solar cells. In this study, we adopted a synthetic strategy with lead thiocyanate (Pb(SCN)2) additive and methylammonium chloride (MACl) posttreatment to enhance the crystallinity and improve the interface of WBG perovskite films with a bandgap of 1.68 eV. The excessive PbI2 was formed at grain boundaries and converted into MAPbI3-xClx perovskites, which are utilized to form the graded heterojunction (GHJ) and compressive strain. This is beneficial for passivating nonradiative recombination defects, suppressing halide phase segregation, and facilitating carrier extraction. Subsequently, the device with GHJ delivered a champion efficiency of 20.30% and superior stability in ambient air and under 85 °C. Finally, we achieved a recorded efficiency of 30.91% for 4-terminal WBG perovskite/TOPCon tandem silicon solar cells. Our findings demonstrate a promising approach for fabricating efficient and stable WBG PSCs through the formation of GHJ.

[Clinical characteristics of in-hospital cardiac arrest in emergency patients in Kashgar area and analysis of influencing factors on success rate of cardiopulmonary resuscitation].

OBJECTIVE: To analyze the clinical characteristics of patients with emergency in-hospital cardiac arrest (IHCA) in Kashgar, Xinjiang Uygur Autonomous Region and the factors affecting the success rate of cardiopulmonary resuscitation. METHODS: Retrospectively selected patients who had cardiac arrest and cardiopulmonary resuscitation in the emergency department of the People's Hospital of 6 counties and cities in Kashgar area from January 2019 to January 2022. The clinical data of all patients were collected, including gender, age, major underlying diseases, the beginning and duration of resuscitation, the number of electric defibrillation acute physiology and chronic health evaluation II (APACHE II). According to whether the resuscitation was successful, all patients were divided into successful resuscitation group and failed resuscitation group. The clinical characteristics of the two groups were compared. Then, the influencing factors of the success rate of cardiopulmonary resuscitation in IHCA patients were analyzed by binary Logistic regression. RESULTS: A total of 1 376 patients were enrolled, including 1 117 cases of failed resuscitation and 259 cases of successful resuscitation. The success rate of resuscitation was 18.82%. Compared with the resuscitation failure group, the patients in the successful resuscitation group were younger (age: 49.10±20.99 vs. 58.44±18.32), the resuscitation start time was earlier [resuscitation start time ≤ 5 minutes: 76.45% (198/259) vs. 66.61% (744/1 117)], the proportion of cardiovascular and cerebrovascular diseases was lower [cardiovascular disease: 49.42% (128/259) vs. 58.19% (650/1 117), cerebrovascular disease: 17.37% (45/259) vs. 21.58% (241/1 117)], the number of electric defibrillation was lower [times: 0 (0, 2) vs. 1 (0, 1)], the proportion of endotracheal intubation was more [80.31% (208/259) vs. 55.60% (621/1 117)], APACHE II score was lower (13.75±8.03 vs. 17.90±4.63), and the difference was statistically significant (all P < 0.01). Binary Logistic regression analysis showed that age, start time of resuscitation, ventilation mode and APACHE II score were protective factors affecting the success rate of cardiopulmonary resuscitation in patients with emergency IHCA [age: odds ratio (OR) = 0.982, 95% confidence interval (95%CI) was 0.973-0.991, P < 0.001; resuscitation start time ≤ 5 minutes: OR = 0.629, 95%CI was 0.409-0.966, P = 0.034; tracheal intubation assisted ventilation: OR = 0.243, 95%CI was 0.149-0.397, P < 0.001; low APACHE II score: OR = 0.871, 95%CI was 0.836-0.907, P < 0.001], while underlying diseases (cardiovascular diseases) are a risk factor affecting the success rate of cardiopulmonary resuscitation (OR = 1.190, 95%CI was 1.015-1.395, P = 0.036). CONCLUSIONS: Age, resuscitation start time, ventilation mode, APACHE II score and major underlying diseases (cardiovascular diseases) have a greater impact on the success rate of resuscitation in IHCA patients. The above factors are conducive to improving or formulating more effective rescue strategies for IHCA patients, so as to achieve the purpose of improving the success rate of clinical treatment.

Mono-dispersed high magnetic resonance sensitive magnetite nanocluster probe for detection of nascent tumors by magnetic resonance molecular imaging.

Sensitive molecular imaging and detection of tumors or their supporting neovascularity require high-avidity, target-specific probes, which produce robust signal amplification compatible with a sensitive high-resolution imaging modality. In this context, we fabricated a high magnetic resonance (MR)-sensitive magnetite nanocluster (MNC) probe specific for tumor angiogenesis by assembly of hydrophobic superparamagnetic iron oxide nanoparticles (SPIONs) with (Mal)mPEG-PLA copolymer into cluster and subsequent encoding c(RGDyC) peptide on the cluster (RGD-MNC) for detection of nascent tumors. We found that RGD-MNC is highly sensitive (r(2) = 464.94 s(-1)mM(-1)) and specific for αvß3-positive cells. Both nascent (35 ± 6.6 mm(3)) and large tumors (256 ± 22.3 mm(3)) can be registered by RGD-MNC and detected by MR imaging (MRI), with the nascent tumors demonstrating more pronounced MR contrast. Immunohistochemical studies revealed that MR signal decrease was closely correlated with histological characteristics of tumors (microvessel density and αvß3 expression levels) at different growth stages.

Interfacial Dipole poly(2-ethyl-2-oxazoline) Modification Triggers Simultaneous Band Alignment and Passivation for Air-Stable Perovskite Solar Cells.

To promote the performance of perovskite solar cells (PSCs), its theoretical power conversion efficiency (PCE) and high stability, elaborative defect passivation, and interfacial engineering at the molecular level are required to regulate the optoelectric properties and charge transporting process at the perovskite/hole transport layer (HTL) interfaces. Herein, we introduce for the first time a multifunctional dipole polymer poly(2-ethyl-2-oxazoline) (PEOz) between the perovskite and Spiro-OMeTAD HTL in planar n-i-p PSCs, which advances the PSCs toward both high efficiency and excellent stability by stimulating three beneficial effects. First, the ether-oxygen unshared electron pairs in PEOz chemically react with unsaturated Pb2+ on the perovskite surfaces by forming a strong Pb-O bond, which effectively reduces the uncoordinated defects on the perovskite surfaces and enhances the absorption ability of the resulting PSCs. Second, the dipole induced by PEOz at the perovskite/HTL interface can decrease the HOMO and LUMO level of Spiro-OMeTAD and optimize the band alignment between these layers, thereby suppressing the interfacial recombination and accelerating the hole transport/extraction ability in the cell. Third, the hygroscopic PEOz thin film can protect perovskite film from water erosion by absorbing the water molecules before perovskite does. Finally, the PEOz-modified PSC exhibits an optimized PCE of 21.86%, with a high short-circuit current density (Jsc) of 24.88 mA/cm2, a fill factor (FF) of 0.79, and an open-circuit voltage (Voc) of 1.11 V. The unencapsulated devices also deliver excellent operation stability over 300 h in an ambient atmosphere with a humidity of 30~40% and more than 10 h under thermal stress.

Multifunctional Imaging of Vessels, Brown Adipose Tissue, and Bones in the Visible and Second Near-infrared Region Using Dual-Emitting Polymer Dots.

Dual-emitting polymer dots (dual-Pdots) in the visible and second near-infrared (NIR-II) region can facilitate the high-resolution imaging of the fine structure and improve the signal-to-noise ratio in in vivo imaging. Herein, combining high brightness of Pdots and multi-scale imaging, we synthesized dual-Pdots using a simple nano-coprecipitation method and performed multi-functional imaging of vessels, brown adipose tissue, and bones. Results showed that in vivo blood vessel imaging had a high resolution of up to 5.9 µm and bone imaging had a signal-to-noise ratio of 3.9. Moreover, dual-Pdots can accumulate in the interscapular brown adipose tissue within 2 min with a signal-to-noise ratio of 5.8. In addition, the prepared dual-Pdots can image the lymphatic valves and the frequency of contraction. Our study provides a feasible method of using Pdots as nanoprobes for multi-scale imaging in the fields of metabolic disorders, skeletal system diseases, and circulatory systems.