A 3,3'-Difluoro-2,2'-Bithiophene Based Donor Polymer Realizing High Efficiency (>17%) Single Junction Binary Organic Solar Cells.

In this study, two novel donor-acceptor (D-A) copolymers are designed and synthesized, DTBT-2T and DTBT-2T2F with 2,2'-bithiophene or 3,3'-difluoro-2,2'-bithiophene as the donor unit and dithienobenzothiadiazole as the acceptor unit, and used them as donor materials in non-fullerene organic solar cells (OSCs). Due to enhanced planarity of polymer chains resulted by the intramolecular F···S noncovalent interactions, the incorporation of 3,3'-difluoro-2,2'-bithiophene unit instead of 2,2'-bithiophene into the polymers can enhance their molecular packing, crystallinity and hole mobility. The DTBT-2T:L8-BO based binary OSCs deliver a power conversion efficiency (PCE) of only 9.71% with a Voc of 0.78 V, a Jsc of 20.69 mA cm-2 , and an FF of 59.67%. Moreover, the introduction of fluoro atoms can lower the highest occupied molecular orbital levels. As a result, DTBT-2T2F:L8-BO based single-junction binary OSCs exhibited less recombination loss, more balanced charge mobility, and more favorable morphology, resulting in an impressive PCE of 17.03% with a higher Voc of 0.89 V, a Jsc of 25.40 mA cm-2, and an FF of 75.74%. These results indicate that 3,3'-difluoro-2,2'-bithiophene unit can be used as an effective building block to synthesize high performance polymer donor materials. This work greatly expands the selection range of donor units for constructing high-performance polymers.

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Neurodevelopmental disorders in children have become a significant global public health concern, impacting child health worldwide. In China, the current intervention model for high-risk infants involves early diagnosis and early treatment. However, in recent years, overseas studies have explored novel preventive early intervention strategies for neurodevelopmental disorders in high-risk infants, achieving promising results. This article provides a comprehensive review of the optimal timing, methods, and intervention models of the preventive early intervention strategies for neurodevelopmental disorders in high-risk infants. The aim is to enhance the awareness and knowledge of healthcare professionals regarding preventive early intervention strategies for neurodevelopmental disorders in high-risk infants, facilitate clinical research and application of such interventions in China, and ultimately reduce the incidence of neurodevelopmental disorders in this high-risk population.

Suppression of damping in a diamagnetically levitated dielectric sphere via eddy currents and static charge reduction.

Diamagnetically levitated micro-nano oscillators play a crucial role in fundamental physics research and the advancement of high-precision sensors. Achieving high sensitivity in acceleration or force sensing is a fundamental requirement within these research domains. The primary limitation in achieving such sensitivity is thermal noise, which is directly proportional to the motion damping of the oscillator. Theoretical modeling suggests the presence of significant damping mechanisms induced by eddy currents. In this study, we validated the theoretical model by optimizing the structure of the magnet trap, confirming the impact of eddy currents on the damping of the oscillators. Additionally, we observed another type of damping caused by static charge in moving levitated dielectrics. Subsequently, we proposed an innovative theoretical model to explain this phenomenon and verified its validity during the charge neutralization process. Through these efforts, we successfully reduced the total damping from 1.6 mHz to 0.15 mHz, resulting in an order of magnitude improvement in performance. Our sensing system achieved the highest sensitivity of acceleration sensing in diamagnetically levitated submillimeter-scale dielectric to date, measuring 7.6±0.8)×10-10g/Hz. The exploration conducted in this study regarding the analysis and suppression of electromagnetic damping, along with associated thermal noise, holds significant promise for frontier research involving sensing with levitating dielectrics.

Tilianin alleviates lipid deposition and fibrosis in mice with nonalcoholic steatohepatitis by activating the PPARα/Nnat axis.

The understanding and treatment of nonalcoholic steatohepatitis (NASH) are still very limited. This study reports the therapeutic effect of tilianin on mice with NASH and further explores its possible molecular mechanisms. A mice model of NASH was established using low-dose streptozotocin combined with a high-fat diet and tilianin treatment. Liver function was assessed by determining serum aspartate aminotransferase and alanine aminotransferase in serum. Interleukin (IL)-1ß, IL-6, transforming growth factor ß1 (TGF-ß1), and tumor necrosis factor α (TNF-α) levels in serum were determined. Hepatocyte apoptosis was assessed using terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling staining. Oil Red O staining and boron dipyrrin staining were used to determine lipid deposition in liver tissues. Masson staining was used to evaluate liver fibrosis, and immunohistochemistry and western blot analysis were used to determine the expression of target proteins. Tilianin treatment significantly ameliorated liver function, inhibited hepatocyte apoptosis, and reduced lipid deposition and liver fibrosis in mice with NASH. The expression of neuronatin (Nnat) and peroxisome proliferator-activated receptor (PPAR) α was upregulated, whereas that of sterol regulatory element-binding protein 1 (SREBP-1), TGF-ß1, nuclear factor (NF)-κB p65, and phosphorylated p65 was downregulated in the liver tissues of mice with NASH after tilianin treatment. The above effects of tilianin were significantly reversed after Nnat knock-down, but its effect on PPARα expression was unaffected. Thus, the natural drug tilianin shows potential in treatig NASH. Its mechanism of action may be related to the targeted activation of PPARα/Nnat, thereby inhibiting the activation of the NF-κB signaling pathway.

Fast size estimation of single-levitated nanoparticles in a vacuum optomechanical system.

Optical trapping of single nanoparticles in vacuum has various applications in both precise measurements and fundamental physics. However, to date, the number and size of randomly loaded nanoparticles in an optical trap is difficult to determine unless in vacuum. In this Letter, an efficient method for nanoparticle size estimation in an optical tweezer system before the evacuation of air was proposed and demonstrated experimentally, using scattering light from levitated particles. The particle radii deduced from the scattering light power in our proposal and from the kinetic theory of particles in gas match well (with the differences of less than 10%). For sample particles with radii ranging within 50-100 nm, we also provide a preselection rule based on this method, where over half of the trapped particles are verified as single particles. Such a particle analysis method is applicable also for the size estimation of levitated diamond particles, gold particles, and other plasmonic particles and can be applied to discovering novel scattering effects.

The short-term safety and effectiveness of a new distal perforating stent graft in Type B aortic dissection: a retrospective study.

BACKGROUND: Spinal artery ischemia (SCI) events can result from over coverage of the descending thoracic aorta with a coated stent during Thoracic Endovascular Aortic Repair (TEVAR). The aim of this study was to determine whether a new distal perforating stent could reduce the incidence of spinal cord ischemia while remodeling the true lumen. METHODS: TBAD patients treated with Talos stent in the vascular surgery Department of Yan 'an Hospital affiliated to Kunming Medical University between December 2017 and October 2019 were retrospectively analyzed to investigate the short-term safety and effectiveness of Talos stent. RESULTS: A total of the 20 patients, including 14 males and 6 females, with an average age of 52.65 ± 8.98 years (range 37-68 years), were included in the analysis. Stent-grafts were successfully implanted in all patients under local anesthesia, with a technical success rate of 100%. The average operation time was 50.75 ± 13.01 min. A total of 2 cases (10%) presented chest pain associated with intercostal artery ischemia that was relieved on the 3rd and 5th postoperative day, respectively. Postoperative mean follow-up was 16.15 ± 3.99 months. No paraplegia or other complications occurred. And stenting did not induce new tears. No migration, deformation, or fracture of the stents occurred. There was a significant difference in the remolding of the true lumen preoperatively and at 12 months postoperatively (P < 0.05). CONCLUSIONS: Talos stent has achieved satisfactory clinical treatment results in short term.

Ferroelectric Oxide Thin Film with an Out-of-Plane Electrical Conductivity.

Ferroelectricity and electrical conductivity are two fundamentally incompatible properties that are difficult to simultaneously achieve in a material. Here, we combine these two contradictory properties by embedding conducting SrNbO3 micro/nanopillars into a ferroelectric SrNbO3.5 (i.e., Sr2Nb2O7) thin film. The high-Tc ferroelectric SrNbO3.5 thin film is epitaxially grown on a LaAlO3 substrate by pulsed laser deposition. The conducting SrNbO3 micro/nanopillars are introduced into the film via an electron-irradiation-induced SrNbO3.5-to-SrNbO3 phase transformation triggered by a focused electron beam. The sizes and distribution of the SrNbO3 micro/nanopillars can be accurately controlled through artificial manipulation of the electron-irradiation-induced SrNbO3.5-to-SrNbO3 phase transformation. The ferroelectric SrNbO3/SrNbO3.5 thin film with an in-plane polarization exhibits an electrical conductivity in the out-of-plane direction. Such conducting ferroelectric thin films may lead to the discovery of plentiful physical phenomena and have great potential for pyroelectric, photoelectric, and multiferroic applications.

Rapid acquisition through fast mapping: stable memory over time and role of prior knowledge.

In recent years, there have been intensive debates on whether healthy adults acquire new word knowledge through fast mapping (FM) by a different mechanism from explicit encoding (EE). In this study, we focused on this issue and investigated to what extent retention interval, prior knowledge (PK), and lure type modulated memory after FM and EE. Healthy young participants were asked to learn novel word-picture associations through both FM and EE. Half of the pictures were from familiar categories (i.e., high PK) and the other half were from unfamiliar categories (i.e., low PK). After 10 min and 1 wk, the participants were tested by forced-choice (FC) tasks, with lures from different categories (Experiment 1) or from the same categories of the target pictures (Experiment 2). Pseudowords were used to denote names of the novel pictures and baseline performance was controlled for each task. The results showed that in both Experiments 1 and 2, memory performance remained stable after FM, while it declined after EE from 10 min to 1 wk. Moreover, the effect of PK appeared at 10 min after FM while at 1 wk after EE in Experiment 2. PK enhanced memory of word-picture associations when the lures were from the same categories (Experiment 2), rather than from different categories (Experiment 1). These results were largely confirmed in Experiment 3 when encoding condition was manipulated as a between-subjects factor, while lure type as a within-subjects factor. The findings suggest that different from EE, FM facilitates rapid acquisition and consolidation of word-picture knowledge, and highlight that PK plays an important role in this process by enhancing access to detailed information.

Role of the hippocampus in the spacing effect during memory retrieval.

It is well known that distributed learning (DL) leads to improved memory performance compared with massed learning (ML) (i.e., spacing effect). However, the extent to which the hippocampus is involved in the spacing effect at shorter and longer retention intervals remains unclear. To address this issue, two groups of participants were asked to encode face-scene pairs at 20-min, 1-day, and 1-month intervals before they were scanned using fMRI during an associative recognition task. The pairs were repeated six times in either a massed (i.e., six times in 1 day) or a distributed (i.e., six times over 3 days, twice per day) manner. The results showed that compared with that in the ML group, the activation of the left hippocampus was stronger in the DL group when the participants retrieved old pairs correctly and rejected new pairs correctly at different retention intervals. In addition, the posterior hippocampus was more strongly activated when the new associations were rejected correctly after DL than ML, especially at the 1-month interval. Hence, our results provide evidence that the hippocampus is involved in better memory performance after DL compared to ML at both shorter and longer retention intervals.

Dysregulation of microRNA-657 influences inflammatory response via targeting interleukin-37 in gestational diabetes mellitus.

A number of studies have implicated that microRNAs (miRNAs) play a critical role in the development of gestational diabetes mellitus (GDM). However, the role of miR-657 in GDM remains vague up to date. We aim to investigate the modifying effect of miR-657 on GDM, which will provide new insight into the pathogenesis of GDM and may help to identify new diagnostic or therapeutic targets for GDM. Increased expression of miR-657 but decreased expression of interleukin-37 (IL-37) was observed in patients with GDM. Besides, negative association between miR-657 and IL-37 was demonstrated in this study. miR-657 could targetedly regulate IL-37 and enhance the proliferation of mononuclear macrophages. Moreover, miR-657 promoted the generation of inflammatory cytokines (IL-6 and tumor necrosis factor-α [TNF-α]) and activation of nuclear factor κB (NF-κB) in lipopolysaccharide-induced mononuclear macrophages, while its effect was significantly inhibited when exogenous recombinant IL-37 was administrated into cells. Accordingly, dysregulation of miR-657 contributes to the pathogenesis of GDM via IL-37/NF-κB signaling axis.

Detecting Axial Ratio of Microwave Field with High Resolution Using NV Centers in Diamond.

Polarization property characterization of the microwave (MW) field with high speed and resolution is vitally beneficial as the circularly-polarized MW field plays an important role in the development of quantum technologies and satellite communication technologies. In this work, we propose a scheme to detect the axial ratio of the MW field with optical diffraction limit resolution with a nitrogen vacancy (NV) center in diamond. Firstly, the idea of polarization selective detection of the MW magnetic field is carried out using a single NV center implanted in a type-IIa CVD diamond with a confocal microscope system achieving a sensitivity of 1.7 µ T/ Hz . Then, high speed wide-field characterization of the MW magnetic field at the submillimeter scale is realized by combining wide-field microscopy and ensemble NV centers inherent in a general CVD diamond. The precision axial ratio can be detected by measuring the magnitudes of two counter-rotating circularly-polarized MW magnetic fields. The wide-field detection of the axial ratio and strength parameters of microwave fields enables high speed testing of small-scale microwave devices.

Thickness dependent surface plasmon of silver film detected by nitrogen vacancy centers in diamond.

Precise detection of surface plasmons is crucial for the research of nanophotonics and quantum optics. In this Letter, we used a single nitrogen vacancy center in diamond as a probe to detect the surface plasmon that was tuned by the thickness of a metallic film. The fluorescence intensity and lifetime of the nitrogen vacancy (NV) center were measured to obtain the information of local light-matter interaction. A nonlinear thickness dependent change of the surface plasmon was observed, with the maximum at the thickness of approximately 30 nm. With optimized thickness of silver film, the fluorescence intensity of a single NV center was enhanced 2.6 times, and the lifetime was reduced by a factor of 3, without affecting the coherence time of the NV spin state. The results proved that this system can quantitatively detect the light-matter interaction at nanoscale, and it provides an approach to enhance the fluorescence intensity of a quantum emitter.

Highly Efficient Planar Perovskite Solar Cells Via Interfacial Modification with Fullerene Derivatives.

Planar heterojunction perovskite solar cells with a high efficiency up to 17.76% are fabricated by modifying the compact TiO2 (c-TiO2) with a [6,6]-phenyl-C61-butyric acid (PCBA) monolayer. High quality CH3NH3PbI3 films can be easily fabricated on PCBA-modified c-TiO2 substrates by a one-step solution processing method. Significant improvements of the device parameters are observed after PCBA modification. A high open-circuit voltage (Voc) of 1.16 V has been achieved, indicating that the PCBA monolayer can act as a hole blocking layer to reduce the trap site density atop the c-TiO2 and the hole recombination at the c-TiO2 /perovskite interface. The enhancement of the fill factor, as well as the partial quenching of the fluorescence of perovskite after modification with PCBA, reveals that the charge extraction is improved.

Performance Enhancement of Polymer Solar Cells by Using Two Polymer Donors with Complementary Absorption Spectra.

Performance enhancement of polymer solar cells (PSCs) is achieved by expanding the absorption of the active layer of devices. To better match the spectrum of solar radiation, two polymers with different band gaps are used as the donor material to fabricate ternary polymer cells. Ternary blend PSCs exhibit an enhanced short-circuit current density and open-circuit voltage in comparison with the corresponding HD-PDFC-DTBT (HD)- and DT-PDPPTPT (DPP)-based binary polymer solar cells, respectively. Ternary PSCs show a power conversion efficiency (PCE) of 6.71%, surpassing the corresponding binary PSCs. This work demonstrates that the fabrication of ternary PSCs by using two polymers with complementary absorption is an effective way to improve the device performance.

High-efficiency large-bandgap material for polymer solar cells.

High-molecular-weight conjugated polymer HD-PDFC-DTBT with N-(2-hexyldecyl)-3,6-difluorocarbazole as the donor unit, 5,6-bis(octyloxy)benzothiadiazole as the acceptor unit, and thiophene as the spacer is synthesized by Suzuki polycondensation. HD-PDFC-DTBT shows a large bandgap of 1.96 eV and a high hole mobility of 0.16 cm(2) V(-1) s(-1) . HD-PDFC-DTBT:PC71 BM-based inverted polymer solar cells (PSCs) give a power conversion efficiency (PCE) of 7.39% with a Voc of 0.93 V, a Jsc of 14.11 mA cm(-2) , and an FF of 0.56.

Planar conjugated polymers containing 9,10-disubstituted phenanthrene units for efficient polymer solar cells.

Four novel conjugated polymers (P1-4) with 9,10-disubstituted phenanthrene (PhA) as the donor unit and 5,6-bis(octyloxy)benzothiadiazole as the acceptor unit are synthesized and characterized. These polymers are of medium bandgaps (2.0 eV), low-lying HOMO energy levels (below -5.3 eV), and high hole mobilities (in the range of 3.6 × 10(-3) to 0.02 cm(2) V(-1) s(-1) ). Bulk heterojunction (BHJ) polymer solar cells (PSCs) with P1-4:PC71 BM blends as the active layer and an alcohol-soluble fullerene derivative (FN-C60) as the interfacial layer between the active layer and cathode give the best power conversion efficiency (PCE) of 4.24%, indicating that 9,10-disubstituted PhA are potential donor materials for high-efficiency BHJ PSCs.

Evaluation for Performance of Body Composition Index Based on Quantitative Computed Tomography in the Prediction of Metabolic Syndrome.

Objective: We aimed to evaluate the performance of predicting metabolic syndrome (MS) using body composition indices obtained by quantitative computed tomography (QCT). Methods: In this cross-sectional study, data were collected from 4745 adults who underwent QCT examinations at a Chongqing teaching hospital between July 2020 and March 2022. Visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), total abdominal fat (TAT), abdominal muscle tissue (AMT), and liver fat content (LFC) were measured at the L2-L3 disc level using specialized software, and the skeletal muscle index (SMI) were calculated. The correlations between body composition indicators were analyzed using the Pearson correlation analysis. Receiver operating characteristic (ROC) curve analysis and area under the curve (AUC) were used to assess these indicators' predictive potential for MS. Results: VAT and TAT exhibited the best predictive ability for MS, with AUCs of 0.797 [95% confidence interval (CI): 0.779-0.815] and 0.794 (95% CI: 0.775-0.812) in males, and 0.811 (95% CI: 0.785-0.836) and 0.802 (95% CI: 0.774-0.830) in females. The AUCs for VAT and TAT were the same but significantly higher than body mass index and other body composition measures. SAT also demonstrated good predictive power in females [AUC = 0.725 (95%CI: 0.692-0.759)] but fair power in males [AUC = 0.6673 (95%CI: 0.650-0.696)]. LFC showed average predictive ability, AMT showed average predictive ability in males but poor ability in females, and SMI had no predictive ability. Correlation analysis revealed a strong correlation between VAT and TAT (males: r = 0.95, females: r = 0.89). SAT was strongly correlated with TAT only in females (r = 0.89). In the male group, the optimal thresholds for VAT and TAT were 207.6 and 318.7 cm2, respectively; in the female group, the optimal thresholds for VAT and TAT were 128.0 and 269.4 cm2, respectively. Conclusions: VAT and TAT are the best predictors of MS. SAT and LFC can also be acceptable to make predictions, whereas AMT can only make predictions of MS in males.

Associations between body size and visual impairment of first-year university students in Chongqing: A cross-sectional study.

The relationship between body size and visual impairment (VI) presents a controversial topic in the health sciences. This study aims to evaluate and clarify the potential associations between these 2 variables. We conducted a cross-sectional study on first-year students enrolled in 2022 at the Southwest University of Political Science & Law. The students underwent a series of physical examinations and visual acuity tests. Visual impairment was classified into 3 categories: mild, moderate, or severe. We used logistic regression analysis to examine the association between body size and VI. Our findings indicated a high prevalence of VI among first-year university students; more than 80% of them were affected. In bivariate analysis, height and weight were negatively related to the presence of VI. However, BMI (body mass index) was not related to VI. By adjusting all available confounders, no associations between BMI (OR = 1.002, 95% CI = 0.974-1.032, P = .877), height (OR = 0.998, 95% CI = 0.967-1.010, P = .298), weight (OR = 0.999, 95% CI = 989-1.009, P = .860), and mild-severe VI were found in females. For males, the ORs were 0.988 (95% CI = 0.955-1.021, P = .459), 0.980 (95% CI = 0.954-1.006, P = .135), and 0.995 (95% CI = 0.985-1.004, P = .285) for BMI, height, and weight, respectively. Among young adults demonstrating high academic performance in high schools, the cessation of physical growth, combined with potential eye strain resulting from overuse, may mitigate any previously observed positive associations between physical status and VI in younger children.

Synergistic Improvement of Strength Characteristics in Recycled Aggregates Using Nano-Clay and Polypropylene Fiber.

In order to study the improvement effect of nano-clay and polypropylene fiber on the mechanical properties of recycled aggregates, unconfined compression tests and triaxial shear tests were conducted. The experimental results show that adding polypropylene fibers to recycled aggregates increases the unconfined compressive strength by 27% and significantly improves ductility. We added 6% nano-clay to fiber-reinforced recycled aggregates, which increased the unconfined compressive strength of the recycled aggregates by 49% and the residual stress by 146%. However, the ductility decreased. Under low confining pressures, with the addition of nano-clay, the peak deviatoric stress strength of the fiber-reinforced recycled aggregates first decreased and then increased. When the nano-clay content was 8%, this reached a maximum value. However, under high confining pressures, the recycled aggregate particles were tightly interlocked, so that the improvement effect of the fiber and nano-clay was not obvious. As more nano-clay was added, the friction angle of the fiber-reinforced recycled aggregates decreased, while the cohesion increased. When the content of nano-clay was 8%, the cohesive force increased by 110%. The results of this research indicate that adding both polypropylene fibers and nano-clay to recycled aggregates has a better improvement effect on their strength characteristics than adding only polypropylene fibers. This study can provide a reference for improving the mechanical properties of recycled aggregates and the use of roadbeds.

Halogenated Nonfused Ring Electron Acceptor for Organic Solar Cells with a Record Efficiency of over 17.

Three nonfused ring electron acceptors (NFREAs), namely, 3TT-C2-F, 3TT-C2-Cl, and 3TT-C2, are purposefully designed and synthesized with the concept of halogenation. The incorporation of F or/and Cl atoms into the molecular structure (3TT-C2-F and 3TT-C2-Cl) enhances the π-π stacking, improves electron mobility, and regulates the nanofiber morphology of blend films, thus facilitating the exciton dissociation and charge transport. In particular, blend films based on D18:3TT-C2-F demonstrate a high charge mobility, an extended exciton diffusion distance, and a well-formed nanofiber network. These factors contribute to devices with a remarkable power conversion efficiency of 17.19%, surpassing that of 3TT-C2-Cl (16.17%) and 3TT-C2 (15.42%). To the best of knowledge, this represents the highest efficiency achieved in NFREA-based devices up to now. These results highlight the potential of halogenation in NFREAs as a promising approach to enhance the performance of organic solar cells.