Inhibition of calcium-sensing receptor by its antagonist promotes gastrointestinal motility in a Parkinson's disease mouse model.

BACKGROUND: The Calcium-sensing receptor (CaSR) participates in the regulation of gastrointestinal (GI) motility under normal conditions and might be involved in the regulation of GI dysmotility in patients with Parkinson's disease (PD). METHODS: CaSR antagonist-NPS-2143 was applied in in vivo and ex vivo experiments to study the effect and underlying mechanisms of CaSR inhibition on GI dysmotility in the MPTP-induced PD mouse model. FINDINGS: Oral intake of NPS-2143 promoted GI motility in PD mice as shown by the increased gastric emptying rate and shortened whole gut transit time together with improved weight and water content in the feces of PD mice, and the lack of influence on normal mice. Meanwhile, the number of cholinergic neurons, the proportion of serotonergic neurons, as well as the levels of acetylcholine and serotonin increased, but the numbers of nitrergic and tyrosine hydroxylase immunoreactive neurons, and the levels of nitric oxide synthase and dopamine decreased in the myenteric plexus in the gastric antrum and colon of PD mice in response to NPS-2143 treatment. Furthermore, the numbers of c-fos positive neurons in the nucleus tractus solitarius (NTS) and cholinergic neurons in the dorsal motor nucleus of the vagus (DMV) increased in NPS-2143 treated PD mice, suggesting the involvement of both the enteric (ENS) and central (CNS) nervous systems. However, ex vivo results showed that NPS-2143 directly inhibited the contractility of antral and colonic strips in PD mice via a non-ENS mediated mechanism. Further studies revealed that NPS-2143 directly inhibited the voltage gated Ca2+ channels, which might, at least in part, explain its direct inhibitory effects on the GI muscle strips. INTERPRETATION: CaSR inhibition by its antagonist ameliorated GI dysmotility in PD mice via coordinated neuronal regulation by both ENS and CNS in vivo, although the direct effects of CaSR inhibition on GI muscle strips were suppressive.

Weak-Interaction Environment in a Composite Electrolyte Enabling Ultralong-Cycling High-Voltage Solid-State Lithium Batteries.

Poly(vinylidene fluoride) (PVDF)-based solid electrolytes with a Li salt-polymer-little residual solvent configuration are promising candidates for solid-state batteries. Herein, we clarify the microstructure of PVDF-based composite electrolyte at the atomic level and demonstrate that the Li+-interaction environment determines both interfacial stability and ion-transport capability. The polymer works as a "solid diluent" and the filler realizes a uniform solvent distribution. We propose a universal strategy of constructing a weak-interaction environment by replacing the conventional N,N-dimethylformamide (DMF) solvent with the designed 2,2,2-trifluoroacetamide (TFA). The lower Li+ binding energy of TFA forms abundant aggregates to generate inorganic-rich interphases for interfacial compatibility. The weaker interactions of TFA with PVDF and filler achieve high ionic conductivity (7.0 × 10-4 S cm-1) of the electrolyte. The solid-state Li||LiNi0.8Co0.1Mn0.1O2 cells stably cycle 4900 and 3000 times with cutoff voltages of 4.3 and 4.5 V, respectively, as well as deliver superior stability at -20 to 45 °C and a high energy density of 300 Wh kg-1 in pouch cells.

Two new diatom species of the genus Gomphonemopsis (Bacillariophyceae) from the coast of China and two new combinations for the genus.

Two new diatom species belonging to the genus Gomphonemopsis are described, Gomphonemopsisnanasp. nov. and Gomphonemopsisgaoisp. nov. These two species were compared in detail with congeners. Gomphonemopsisnana is distinguished by its high stria density and small size. This species was found so far to be epiphytic only on the eelgrass collected from Qingdao Bay (Yellow Sea). Gomphonemopsisgaoi is characterized by its isopolar valves, simple proximal raphe endings and acutely rounded apices. This taxon was separated from the exoskeleton of marine copepods sampled from the Futian Mangrove Nature Reserve (South China Sea). In addition, two new combinations, Gomphonemopsisoahuensis (Hustedt) Lang Li, Yuhang Li & Changping Chen, comb. nov. and Gomphonemopsisplatypus (Østrup) Lang Li, Yuhang Li & Junxiang Lai, comb. nov. are proposed. This study increases the records and knowledge of Gomphonemopsis along the coast of China.

First Report of Tomato Yellow Mottle-Associated Virus Infecting Tobacco in China.

Tomato yellow mottle-associated virus (TYMaV) belongs to the genus Cytorhabdovirus in the family Rhabdoviridae and has been reported to infect a variety of Solanaceae crops, such as Solanum lycopersicum, S. nigrum, Capsicum annuum and Nicotiana benthamiana (Li et al. 2022, Li et al. 2023, Xu et al. 2017, Zhou et al. 2019). In August 2022, about 500 out of 2000 tobacco (N. tabacum) plants showing leaf distortion, crinkling and mosaic symptoms were found in one tobacco growing field in Xingren City, Guizhou Province, China. To identify the causal pathogen(s), leaves from 20 symptomatic tobacco plants were collected and pooled to perform small RNA deep sequencing (sRNA-Seq) and assembly. Briefly, total RNA was extracted with TRIzol Reagent (Takara, Kusatsu, Japan). A small RNA cDNA library was constructed by the small RNA Sample Pre Kit. sRNA-Seq was performed with an Illumina NovaSeq 6000 platform. About 29 million reads were obtained and 334 contigs generated after removal of host-derived sequences. Among them, 31 unique contigs mapped to the TYMaV genome (NC_034240.1), covering 28.43% of the genome with the mean read coverage of 0.92%. Meanwhile, 226 contigs mapped to the genome of a potyvirus, chilli veinal mottle virus (ChiVMV, NC_005778.1), covering 88.79% of the genome with the mean read coverage of 0.83%. To verify the sRNA-Seq result for TYMaV identification, reverse transcription (RT)- PCR was performed with specific primers TYMaV-F (5'-CTGACGTAGTGTTGGCAGAT-3') and TYMaV-R (5'-AACCTCCATGCAGAACCATGG-3'). The expected-size 936-bp fragment was amplified from total RNA of all 20 samples. Dot enzyme-linked immunosorbent assays (Dot-ELISA) with antibody for TYMaV (kindly provided by Dr. Zhenggang Li from Guangdong Academy of Agricultural Sciences) were performed and further verified TYMaV infection. In addition, five asymptomatic tobacco plants from the same field as controls were used to detect TYMaV by RT-PCR and Dot-ELISA, and all samples showed negative test results. Subsequently, 17 primer pairs (Supplementary Table 1) were used to obtain the full-length sequence of TYMaV from a single positive tobacco sample by RT-PCR, followed by Sanger sequencing at Sangon Biotech (Shanghai, China). The resulting amplicon sequences were assembled into a nearly full-length genome sequence of a TYMaV isolate from tobacco in Guizhou (TYMaV-GZ). BLASTn analysis of the 13, 393 nt-long sequence (GeneBank accession number, PP444718) revealed 84.7% and 87.2% nt sequence identity with the TYMaV tomato isolate (KY075646.1) and the TYMaV S. nigrum isolate (MW527091.1), respectively. Moreover, five S. nigrum plants showing leaf crinkling and mosaic symptoms from tobacco fields tested positive for TYMaV by RT-PCR assay, suggesting a potential spread of TYMaV between tobacco and S. nigrum, which may serve as a reservoir for the virus in the tobacco fields. However, the transmission route of TYMaV remains unknown, and further verification is needed. To our knowledge, this is the first report of TYMaV infecting tobacco crop in China. It will be important to assess the potential economic importance of TYMaV to tobacco production in China and elsewhere, and to elucidate the respective roles of this virus and ChiVMV in the leaf distorting and yellowing symptoms.

Deciphering the pharmacological mechanisms of Shenlingbaizhu formula in antibiotic-associated diarrhea treatment: Network pharmacological analysis and experimental validation.

ETHNOPHARMACOLOGICAL RELEVANCE: Shenlingbaizhu (SLBZ) formula, a classical traditional Chinese medicinal (TCM) formula, has been widely used for treating antibiotic-associated diarrhea (AAD). However, the underlying pharmacological mechanisms have not yet been investigated thoroughly. AIM OF THE STUDY: To explore the remission mechanism of SLBZ in the treatment of AAD, we conducted network pharmacological analysis and experimental validation in vitro and in vivo. MATERIALS AND METHODS: In this study, the main compounds of SLBZ were identified by ultra-high-performance liquid chromatography-mass spectroscopy (UHPLC-MS) and online databases. The targets of the active components and AAD-related targets were predicted by network pharmacology, and the potential targets of SLBZ against AAD were obtained. Then the core targets were recognized after Protein-Protein Interaction (PPI) analysis. Based on these, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway analyses were conducted, and the key pathway was screened. Subsequently, molecular docking was performed using Auto Dock Vina to find the key components that played a crucial role in that pathway. Molecular dynamics simulation was performed by Gromacs software to detect the binding mode. Finally, the results were confirmed by in vitro and in vivo experiments. RESULTS: A total of 66 active ingredients of SLBZ were detected by UHPLC-MS, and 128 active ingredients were screened out by network pharmacological analysis. Additionally, 935 drug targets and 1686 AAD-related targets were obtained. Seventy-eight intersected genes were selected as potential therapeutic targets and 19 genes were excavated as core targets. Enrichment analysis revealed PI3K-AKT signaling pathway was the key pathway in SLBZ against AAD. Topological analysis further revealed that JAK2, MTOR, TLR4, and SYK were the key targets affected by SLBZ on the PI3K-AKT pathway, and 52 components of SLBZ were associated with them. Molecular docking and dynamics simulation revealed strong binding affinities between MTOR and diosgenin. Subsequently, after SLBZ treatment, the expression levels of JAK2, MTOR, TLR4, and SYK were found significantly upregulated in the AAD model rats (p < 0.05). The cell experiment further validated the good binding ability between MTOR and diosgenin. CONCLUSION: We demonstrate that the therapeutic effect of SLBZ on AAD was achieved in part by inhibiting the PI3K-AKT pathway.

Six-orders-of-magnitude-spanning dispersion measurement via Kalman filtering-aided white-light interferometry.

Dispersion plays a great role in ultrafast laser oscillators, ultrashort pulse amplifiers, and many other nonlinear optical dynamics. Therefore, dispersion measurement is crucial for device characterization, system design and nonlinear dynamics investigation therein. In this work, we demonstrate a versatile approach, i.e., Kalman filtering-aided white-light interferometry, for group delay dispersion (GDD) characterization. Extended Kalman filter is adopted to track the cosine-like interferogram, and to eliminate the unintended bias and the envelope, providing a nearly ideal phase retrieval and GDD estimation. The measurement range could span from tens of fs2 to tens of ps2, with an uncertainty of about 0.1%, enabling precise GDD measurement for diverse optical components, ranging from a millimeter-thick glass slide to highly dispersive chirped fiber Bragg gratings. Benefited by the simplicity, convenient setup, and easy operation as well as relatively low cost, this approach would help photonic device characterization, dispersion management and nonlinear dynamics investigation in the laboratory and work plant.

Manipulating chiral spin transport with ferroelectric polarization.

A magnon is a collective excitation of the spin structure in a magnetic insulator and can transmit spin angular momentum with negligible dissipation. This quantum of a spin wave has always been manipulated through magnetic dipoles (that is, by breaking time-reversal symmetry). Here we report the experimental observation of chiral spin transport in multiferroic BiFeO3 and its control by reversing the ferroelectric polarization (that is, by breaking spatial inversion symmetry). The ferroelectrically controlled magnons show up to 18% modulation at room temperature. The spin torque that the magnons in BiFeO3 carry can be used to efficiently switch the magnetization of adjacent magnets, with a spin-torque efficiency comparable to the spin Hall effect in heavy metals. Utilizing such controllable magnon generation and transmission in BiFeO3, an all-oxide, energy-scalable logic is demonstrated composed of spin-orbit injection, detection and magnetoelectric control. Our observations open a new chapter of multiferroic magnons and pave another path towards low-dissipation nanoelectronics.

Challenges and opportunities in human dimensions behind cat-wildlife conflict.

Because global anthropogenic activities cause vast biodiversity loss, human dimensions research is essential to forming management plans applicable to biodiversity conservation outside wilderness areas. Engaging public participation is crucial in this context to achieve social and environmental benefits. However, knowledge gaps remain in understanding how a balance between conservation and public demands can be reached and how complicated sociocultural contexts in the Anthropocene can be incorporated in conservation planning. We examined China's nationwide conflict between free-ranging cats (owned cats that are allowed to go outdoors or homeless cats living outdoors) and wildlife to examine how a consensus between compassion and biodiversity conservation can help in decision-making. We surveyed a random sample of people in China online. Over 9000 questionnaires were completed (44.2% response). In aggregate, respondents reported approximately 29 million free-ranging owned cats and that over 5 million domestic cats per year become feral in mainland China. Respondents who were cat owners, female, and religious were more likely to deny the negative impacts of cats on wildlife and ongoing management strategies and more supportive of stray cat shelters, adoption, and community-based fund raising than nonowners, male, and nonreligious respondents (p < 0.05). Free-ranging cat ownership and abandonment occurred less with owners with more knowledge of biodiversity and invasive species than with respondents with less knowledge of these subjects (p < 0.05). We recommend that cat enthusiasts and wildlife conservationists participate in community-based initiatives, such as campaigns to keep cats indoors. Our study provides a substantially useful framework for other regions where free-ranging cats are undergoing rapid expansion.

Retos y oportunidades de las dimensiones humanas detrás del conflicto entre gatos y fauna Resumen Debido a que las actividades antropogénicas globales causan una enorme pérdida de la biodiversidad, la investigación sobre las dimensiones humanas es esencial para generar planes de manejo aplicables a la conservación de la biodiversidad fuera de las áreas silvestres. Es muy importante lograr que el público participe en este contexto para obtener los beneficios sociales y ambientales. Sin embargo, todavía existen vacíos en el conocimiento sobre cómo lograr el balance entre la conservación y las demandas públicas y cómo incorporar los contextos socioculturales complejos del Antropoceno a la planeación de la conservación. Analizamos el conflicto nacional entre los gatos libres (gatos callejeros o gatos domésticos que se les permite salir) y la fauna en China para estudiar cómo un consenso entre la compasión y la conservación de la biodiversidad puede ayudar en la toma de decisiones. Encuestamos en línea a una muestra aleatoria de personas en China. Se completaron más de 9000 cuestionarios (44.2% de respuesta). En total, los respondientes reportaron un aproximado de 29 millones de gatos libres y que más de cinco millones de gatos domésticos se vuelven ferales al año en China. Quienes respondieron y son dueños de gatos, mujeres y religiosos tuvieron la mayor probabilidad de negar los impactos negativos de los gatos sobre la fauna y de las estrategias actuales de manejo y de mostrar más apoyo por los refugios de gatos abandonados, la adopción y de la recaudación de fondos comunitaria que quienes no son dueños, no son religiosos y son hombres (p < 0.05). La propiedad de gatos libres y el abandono ocurrieron menos con los dueños con más conocimiento sobre la biodiversidad y las especies invasoras que con los respondientes con menos conocimiento sobre estos temas (p < 0.05). Recomendamos que los aficionados a los gatos y los conservacionistas de la fauna participen en las iniciativas comunitarias; por ejemplo, campañas para mantener a los gatos dentro de casa. Nuestro estudio proporciona un marco sustancialmente útil para otras regiones en donde los gatos libres se encuentran en rápida expansión.

Broadband nonlinear modulation of incoherent light using a transparent optoelectronic neuron array.

Nonlinear optical processing of ambient natural light is highly desired for computational imaging and sensing. Strong optical nonlinear response under weak broadband incoherent light is essential for this purpose. By merging 2D transparent phototransistors (TPTs) with liquid crystal (LC) modulators, we create an optoelectronic neuron array that allows self-amplitude modulation of spatially incoherent light, achieving a large nonlinear contrast over a broad spectrum at orders-of-magnitude lower intensity than achievable in most optical nonlinear materials. We fabricated a 10,000-pixel array of optoelectronic neurons, and experimentally demonstrated an intelligent imaging system that instantly attenuates intense glares while retaining the weaker-intensity objects captured by a cellphone camera. This intelligent glare-reduction is important for various imaging applications, including autonomous driving, machine vision, and security cameras. The rapid nonlinear processing of incoherent broadband light might also find applications in optical computing, where nonlinear activation functions for ambient light conditions are highly sought.

Ultrafast removal of organics via peroxymonosulfate activation over Co2P/TD hollow spheres derived from ZIF-67.

Co2P/tetrasodium diphosphate (TD) derived from ZIF-67/sodium phytate was newly developed and synthesized, and exhibited excellent degradation ability toward various refractory organics via peroxymonosulfate activation. A corresponding reaction mechanism was proposed. In addition, a continuous-flow operation of phenol degradation was realized.

Two-Level Spatio-Temporal Feature Fused Two-Stream Network for Micro-Expression Recognition.

Micro-expressions, which are spontaneous and difficult to suppress, reveal a person's true emotions. They are characterized by short duration and low intensity, making the task of micro-expression recognition challenging in the field of emotion computing. In recent years, deep learning-based feature extraction and fusion techniques have been widely used for micro-expression recognition, particularly methods based on Vision Transformer that have gained popularity. However, the Vision Transformer-based architecture used in micro-expression recognition involves a significant amount of invalid computation. Additionally, in the traditional two-stream architecture, although separate streams are combined through late fusion, only the output features from the deepest level of the network are utilized for classification, thus limiting the network's ability to capture subtle details due to the lack of fine-grained information. To address these issues, we propose a new two-level spatio-temporal feature fused with a two-stream architecture. This architecture includes a spatial encoder (modified ResNet) for learning texture features of the face, a temporal encoder (Swin Transformer) for learning facial muscle motor features, a feature fusion algorithm for integrating multi-level spatio-temporal features, a classification head, and a weighted average operator for temporal aggregation. The two-stream architecture has the advantage of extracting richer features compared to the single-stream architecture, leading to improved performance. The shifted window scheme of Swin Transformer restricts self-attention computation to non-overlapping local windows and allows cross-window connections, significantly improving the performance and reducing the computation compared to Vision Transformer. Moreover, the modified ResNet is computationally less intensive. Our proposed feature fusion algorithm leverages the similarity in output feature shapes at each stage of the two streams, enabling the effective fusion of multi-level spatio-temporal features. This algorithm results in an improvement of approximately 4% in both the F1 score and the UAR. Comprehensive evaluations conducted on three widely used spontaneous micro-expression datasets (SMIC-HS, CASME II, and SAMM) consistently demonstrate the superiority of our approach over comparative methods. Notably, our approach achieves a UAR exceeding 0.905 on CASME II, making it one of the few frameworks in the published micro-expression recognition literature to achieve such high performance.

Baicalein glycymicelle ophthalmic solution: Preparation, in vitro antimicrobial activities, and antimicrobial mechanism evaluations.

The purpose of this study was to develop a novel baicalein (BAI) loaded glycymicelle ophthalmic solution with small molecule phytochemical glycyrrhizin as nanocarriers and to explore this solution's potential as an antimicrobial agent against ocular infections. The optimized BAI glycymicelles had a high encapsulation efficiency (98.76 ±â€¯1.25 %), a small particle size (54.38 ±â€¯2.41 nm), a uniform size distribution (polydispersity index = 0.293 ±â€¯0.083), and a zeta potential of -28.3 ±â€¯1.17 mV. The BAI glycymicelle ophthalmic solution exhibited an excellent short-term storage stability. BAI glycymicelles significantly increased the apparent solubility and in vitro release capability of BAI. The BAI glycymicelle ophthalmic solution exhibited no hen's egg-chorioallantoic membrane' irritation and strong in vivo ocular tolerance in rabbits. The BAI glycymicelles noticeably enhanced the in vivo corneal permeation. The BAI glycymicelles also precipitated increased in vitro antioxidant activity and significantly improved in vitro antipathogen activities. Various antimicrobial mechanisms, including the destruction of the bacterial cell wall, damage to the bacterial cell membranes, interruptions to the biofilm structure, and the apoptosis of bacteria, were inflicted on BAI glycymicelles. These findings provided useful knowledge regarding the development of a novel ophthalmic solution and formulation of BAI.

Interfacial Engineering Boosting the Activity and Stability of MIL-53(Fe) toward Electrocatalytic Nitrogen Reduction.

The electrochemical nitrogen reduction reaction (eNRR) has emerged as a promising strategy for green ammonia synthesis. However, it suffers unsatisfactory reaction performance owing to the low aqueous solubility of N2 in aqueous solution, the high dissociation energy of N≡N, and the unavoidable competing hydrogen evolution reaction (HER). Herein, a MIL-53(Fe)@TiO2 catalyst is designed and synthesized for highly efficient eNRR. Relative to simple MIL-53(Fe), MIL-53(Fe)@TiO2 achieves a 2-fold enhancement in the Faradaic efficiency (FE) with an improved ammonia yield rate by 76.5% at -0.1 V versus reversible hydrogen electrode (RHE). After four cycles of electrocatalysis, MIL-53(Fe)@TiO2 can maintain a good catalytic activity, while MIL-53(Fe) exhibits a significant decrease in the NH3 yield rate and FE by 79.8 and 82.3%, respectively. Benefiting from the synergetic effect between TiO2 and MIL-53(Fe) in the composites, Fe3+ ions can be greatly stabilized in MIL-53(Fe) during the eNRR process, which greatly hinders the catalyst deactivation caused by the electrochemical reduction of Fe3+ ions. Further, the charge transfer ability in the interface of composites can be improved, and thus, the eNRR activity is significantly boosted. These findings provide a promising insight into the preparation of efficient composite electrocatalysts.

Characterization of the complete chloroplast genome of 'Quanhong poplar' (Populus deltoides W. Bartram ex Humphry Marshall, 2011).

The color of the leaves is one of the most important factors for horticultural crops that are considered by breeders, and is also attracting more and more attention from economists and academics. 'Quanhong poplar' (QHP), a rare, bright reddish-purple color-leaf cultivar that has been widely cultivated in China as a landscape tree, is a very precious color-leaf cultivar. In the present study, a reference-based assembly was performed using whole-genome sequencing data to characterize the chloroplast genome of 'QHP'. The total chloroplast genome size of 'QHP' is 156,950 bp, which is divided into two inverted repeat structures of 27,649 bp each, a small single-copy region of 16,563 bp, and a large single-copy region (LSC) of 85,089 bp. From the chloroplast genome, 130 genes have been predicted, including 85 protein-coding genes, 37 tRNA genes, and eight rRNA genes. A chloroplast genome containing 36.68% GC content was detected in 'QHP'. Three SNP sites have been developed between 'QHP' and Populus deltoides Zhonglin 2025. Based on the phylogenetic analysis of chloroplast genomes reported for Populus, the chloroplast of 'QHP' is closest to several strains of Populus deltoides.

Molecular mechanism of Spatholobi Caulis treatment for cholangiocarcinoma based on network pharmacology, molecular docking, and molecular dynamics simulation.

Cholangiocarcinoma (CCA) is a type of malignant tumor originating from the intrahepatic, periportal, or distal biliary system. The treatment means for CCA is limited, and its prognosis is poor. Spatholobi Caulis (SC) is reported to have effects on anti-inflammatory and anti-tumor, but its role in CCA is unclear. First, the potential molecular mechanism of SC for CCA treatment was explored based on network pharmacology, and the core targets were verified by molecular docking and molecular dynamics simulation. Then, we explored the inhibitory effect of SC on the malignant biological behavior of CCA in vitro and in vivo and also explored the related signaling pathways. The effect of combination therapy of SC and cisplatin (DDP) in CCA was also explored. Finally, we conducted a network pharmacological study and simple experimental verification on luteolin, one of the main components of SC. Network pharmacology analysis showed that the core targets of SC on CCA were AKT1, CASP3, MYC, TP53, and VEGFA. Molecular docking and molecular dynamics simulation indicated a good combination between the core target protein and the corresponding active ingredients. In vitro, SC inhibited proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of CCA cells. In vivo experiments, the results were consistent with in vitro experiments, and there was no significant hepatorenal toxicity of SC at our dosage. Based on KEGG enrichment analysis, we found PI3K/AKT signaling pathway might be the main signaling pathway of SC action on CCA by using AKT agonist SC79. To explore whether SC was related to the chemotherapy sensitivity of CCA, we found that SC combined with DDP could more effectively inhibit the progression of cholangiocarcinoma. Finally, we found luteolin may inhibit the proliferation and invasion of CCA cells. Our study demonstrates for the first time that SC inhibits the progression of CCA by suppressing EMT through the PI3K-AKT signaling pathway, and SC could enhance the effectiveness of cisplatin therapy for CCA.

Rethinking skip connections in Spiking Neural Networks with Time-To-First-Spike coding.

Time-To-First-Spike (TTFS) coding in Spiking Neural Networks (SNNs) offers significant advantages in terms of energy efficiency, closely mimicking the behavior of biological neurons. In this work, we delve into the role of skip connections, a widely used concept in Artificial Neural Networks (ANNs), within the domain of SNNs with TTFS coding. Our focus is on two distinct types of skip connection architectures: (1) addition-based skip connections, and (2) concatenation-based skip connections. We find that addition-based skip connections introduce an additional delay in terms of spike timing. On the other hand, concatenation-based skip connections circumvent this delay but produce time gaps between after-convolution and skip connection paths, thereby restricting the effective mixing of information from these two paths. To mitigate these issues, we propose a novel approach involving a learnable delay for skip connections in the concatenation-based skip connection architecture. This approach successfully bridges the time gap between the convolutional and skip branches, facilitating improved information mixing. We conduct experiments on public datasets including MNIST and Fashion-MNIST, illustrating the advantage of the skip connection in TTFS coding architectures. Additionally, we demonstrate the applicability of TTFS coding on beyond image recognition tasks and extend it to scientific machine-learning tasks, broadening the potential uses of SNNs.

Stretch tuning of dispersion in optical microfibers.

Dispersion management is vital for nonlinear optics and ultrafast lasers. We demonstrate that group velocity dispersion (GVD, or second-order dispersion, i.e., ß2) and group delay dispersion (GDD) in optical microfibers can be tuned simply by stretch due to their remarkable features of small diameter and diameter-dependent dispersion. We experimentally demonstrate that a pulling force of just a few mN would elongate the optical microfibers by up to 5%, bringing a significant change in the ß2 and GDD. This change can be increment or decrement, lying on the diameter of optical microfibers. Therefore, 10-cm-long optical microfibers would provide a GDD change of 104 fs2 when elongated by 5%, well in the elastic limit. Remarkably, this change is equivalent to the GDD (not GDD change) provided by a 0.5-m-long single-mode fiber. Experimental results and simulations show that the GDD change is due to the interplay between elongation, diameter shrink, and refractive index decrease. Benefited from the easy manipulation, tiny pulling force required, and full integration with conventional optical fibers, stretch tuning of dispersion in optical microfibers would find applications in dispersion management for ultrafast lasers and nonlinear optics.

Advances in research and application of photodynamic therapy in cholangiocarcinoma (Review).

Cholangiocarcinoma (CCA) is a disease characterized by insidious clinical manifestations and challenging to diagnose. Patients are usually diagnosed at an advanced stage and miss the opportunity for radical surgery. Therefore, effective palliative therapy is the main treatment approach for unresectable CCA. Current common palliative treatments include biliary drainage, chemotherapy, radiotherapy, targeted therapy and immunotherapy. However, these treatments only offer limited improvement in quality of life and survival. Photodynamic therapy (PDT) is a novel local treatment method that is considered a safe tumor ablation method for numerous cancers. It has shown good efficacy in various studies of CCA and is expected to become an important treatment for CCA. In the present study, the mechanisms of PDT in the treatment of CCA were systematically explored and the progress in the research of photosensitizers was discussed. The current study focused on the various PDT protocols and their therapeutic effects in CCA, with the objective of providing a new horizon for future research and clinical applications of PDT in the treatment of CCA.

Prediction of electrical properties of GAAFET based on integrated learning model.

As device feature sizes continue to decrease and fin field effect transistors (FinFETs) reach their physical limits, gate all around field effect transistors (GAAFETs) have emerged with larger gate control areas and stackable characteristics for better suppression of second-order effects such as short-channel effects due to their gate encircling characteristics. Traditional methods for studying the electrical characteristics of devices are mostly based on the technology computer-aided design (TCAD). Still, it is not conducive to developing new devices due to its time-consuming and inefficient drawbacks. Deep learning (DL) and machine learning (ML) have been well-used in recent years in many fields. In this paper, we propose an integrated learning model that integrates the advantages of DL and ML to solve many problems in traditional methods. This integrated learning model predicts the direct current characteristics, capacitance characteristics, and electrical parameters of GAAFET better than those predicted by DL or ML methods alone, with a linear regression factor (R2) greater than 0.99 and very small root mean square error (RMSE). The proposed integrated learning model achieves fast and accurate prediction of GAAFET electrical characteristics, which provides a new idea for device and circuit simulation and characteristics prediction in microelectronics. .