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1.
Artigo em Inglês | MEDLINE | ID: mdl-39380467

RESUMO

The neuromorphic vision system that utilizes spikes as information carriers is crucial for the formation of spiking neural networks. Here, we present a bioinspired flexible artificial spiking photoreceptor (ASP), which is realized by using a single VO2 Mott memristor that can simultaneously sense and encode the stimulus light into spikes. The ASP has high spike-encoded photosensitivity and ultrawide photosensing range (405-808 nm) with good endurance (>7 × 107) and high flexibility (bending radius ∼5 mm). Then, we put forward an all-spike electronic retina architecture that comprises one layer of ASPs and one layer of artificial optical nerves (AONs) to process the spike information. Each AON consists of a single Mott memristor connected in series with a neuro-transistor that is a multiple-input floating-gate MOS transistor. Simulation results demonstrate that the all-spike electronic retina can successfully segment images with high Shannon entropy, thus laying the foundation for the development of a spike-based neuromorphic vision system.

3.
Proc Natl Acad Sci U S A ; 121(36): e2406343121, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39186654

RESUMO

The extinction risk of the giant panda has been demoted from "endangered" to "vulnerable" on the International Union for Conservation of Nature Red List, but its habitat is more fragmented than ever before, resulting in 33 isolated giant panda populations according to the fourth national survey released by the Chinese government. Further comprehensive investigations of the genetic background and in-depth assessments of the conservation status of wild populations are still necessary and urgently needed. Here, we sequenced the genomes of 612 giant pandas with an average depth of ~26× and generated a high-resolution map of genomic variation with more than 20 million variants covering wild individuals from six mountain ranges and captive representatives in China. We identified distinct genetic clusters within the Minshan population by performing a fine-grained genetic structure. The estimation of inbreeding and genetic load associated with historical population dynamics suggested that future conservation efforts should pay special attention to the Qinling and Liangshan populations. Releasing captive individuals with a genetic background similar to the recipient population appears to be an advantageous genetic rescue strategy for recovering the wild giant panda populations, as this approach introduces fewer deleterious mutations into the wild population than mating with differentiated lineages. These findings emphasize the superiority of large-scale population genomics to provide precise guidelines for future conservation of the giant panda.


Assuntos
Conservação dos Recursos Naturais , Genoma , Ursidae , Ursidae/genética , Animais , Conservação dos Recursos Naturais/métodos , Genoma/genética , China , Espécies em Perigo de Extinção , Variação Genética , Genética Populacional/métodos , Dinâmica Populacional , Sequenciamento Completo do Genoma/métodos
5.
Artigo em Inglês | MEDLINE | ID: mdl-39105431

RESUMO

PURPOSE: This study aimed to clarify the characteristics of delaminated rotator cuff tears (RCTs) and evaluate the clinical outcomes of a modified arthroscopic en masse suture bridge repair for delaminated RCTs. METHODS: Patients with full-thickness RCTs, who underwent arthroscopic suture bridge repair with a minimum 2-year follow-up, were retrospectively reviewed. Patients were categorized into two groups based on the presence of delamination. Delaminated RCTs were treated using a modified en masse suture bridge technique, while nondelaminated RCTs received a conventional suture bridge technique. Preoperative and postoperative Constant scores and American Shoulder and Elbow Surgeons (ASES) scores were determined to evaluate clinical outcomes. Postoperative magnetic resonance imaging (MRI) was carried out to identify the integrity and retear of the repaired rotator cuff. RESULTS: A total of 172 patients were included in our study cohort, in which 67 (39%) delaminated RCTs were confirmed intraoperatively. The prevalence of delamination was significantly higher in large tears (53/102, 52%) compared to medium tears (14/70, 20%) (p < 0.001). No significant differences in age (n.s.) or gender (n.s.) were observed between the two groups. Both groups showed significant improvements in Constant and ASES scores postoperatively (both p < 0.001), with no significant differences between the groups (n.s.). The retear rates were 2/67 (3.0%) in the delamination group and 3/105 (2.9%) in the nondelamination group, showing no significant difference (n.s.). CONCLUSIONS: The modified arthroscopic en masse suture bridge technique was effective for repairing delaminated RCTs, yielding favourable clinical outcomes comparable to those of nondelaminated tears. LEVEL OF EVIDENCE: Level IV.

8.
Front Pharmacol ; 15: 1393526, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39139634

RESUMO

Background: Refractory gastroesophageal reflux disease (refractory GERD) is a heterogeneous disease characterized by unresponsiveness or poor efficacy to proton-pump inhibitors (PPIs). This chronic disorder substantially weakens patients' mental wellbeing and quality of life, increasing the financial burden on society. Multiple articles have been reported in this area. However, literature involving scientometric analysis of refractory GERD is absent. Therefore, it is necessary to understand the evolution of research themes and the main hotspots of refractory GERD through bibliometric methods. Methods: All documents related to refractory GERD based on the WOS Core Collection from January 2000 to November 2023 were selected for analysis. Citespace V 6.1 R6, VOSviewer V 1.6.20, and Scimago Graphica V 1.0.38 were used to perform bibliometric analysis. Results: We collected a total of 241 research articles from 36 countries and 322 institutions, contributed by over 1,000 authors. Over the last 20 years, the number of articles in this field has increased year by year, and since 2011, the number of publications has increased dramatically, with 85.89% of the papers. These countries are led by the United States and Japan. GUT had the highest number of citations and DIGESTION had the highest number of publications. Research on standardized diagnosis and management, mechanisms, novel monitoring methods, and innovative drugs and procedures for refractory GERD are the main topics and hotspots in this field. This study also found that neuroimmune interaction is closely related to refractory GERD, which may be a new direction for future mechanism research. Conclusion: Our study is the first bibliometric analysis of the global literature on refractory GERD. This research provides valuable insights for researchers, enabling them to quickly understand the research frontier and hot topics of this field.

9.
Sci Rep ; 14(1): 16719, 2024 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030243

RESUMO

The purpose of this work is to explore the properties of the lignin-derived amine-free photoinitiating systems (PISs) during the curing process. Four novel hydrogen donors (HD1, HD2, HD3, and HD4) derived from lignin α-O-4 structural were designed and synthesized by simple methods, and their low C-H bond dissociation energies on methylene were determined by molecular orbitals theory. Four experimental groups using CQ (camphorquinone)/HD PIs formulated with Bis-GMA/TEGDMA (70 w%/30 w%) were compared to CQ/EDB (ethyl 4-dimethylamino benzoate) system. The photopolymerization profiles and double bond conversion rate was tracked by FTIR experiments; the color bleaching ability of the samples and color aging test assay were performed using color indexes measurements; The cytotoxicity of the samples was also compared to EDB related systems. All of the experimental groups with new HDs were compared to the control group with EDB by statistical analysis. Compared to CQ/EDB system, new lignin-derived hydrogen donors combined with CQ showed comparable or even better performances in polymerization initiation to form resin samples, under a blue dental LED in air. Excellent color bleaching property was observed with the new HDs. Aging tests and cytotoxicity examination of the resin were performed, indicating the new lignin compounds to be efficient hydrogen donors for amine-free CQ-based photo-initiating system. Novel lignin α-O-4 derived hydrogen donors are promising for further usage in light-curing materials.


Assuntos
Lignina , Polimerização , Lignina/química , Hidrogênio/química , Terpenos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Resinas Sintéticas/química , Materiais Dentários/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Cânfora/análogos & derivados
10.
BMC Oral Health ; 24(1): 818, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39026272

RESUMO

BACKGROUND: This case report highlights the importance of standardized and fully digital sequential treatment in complex occlusal rehabilitation cases. To fully resolve the patient's dental needs, such cases often require multidisciplinary interventions including periodontal therapy, endodontic treatment, anterior esthetics, implant restoration, and prosthetic rehabilitation. A fully digital workflow (including facial scanners, intraoral scanners, jaw motion tracking systems, virtual articulators, and computer-aided design software) streamlined the complex treatment, enhancing workflow simplicity, efficiency, visibility, and precision. CASE PRESENTATION: The patient presented with decreased chewing efficiency of the upper and lower prostheses, along with unsatisfactory esthetic appearance of the anterior teeth. After physical examination and radiological assessment, this complex occlusal rehabilitation case required periodontal therapy, anterior esthetic enhancement, implant restoration, and fixed prosthetic rehabilitation. Therefore, a fully digital workflow was adopted. Full-crown prostheses were placed on teeth 13, 23, and 34; a fixed bridge encompassed positions 32 to 42, and single implant crowns were placed on teeth 35 and 36. Implant-supported fixed bridges were constructed for teeth 12 to 22 and 44 to 46, anchored by implants at teeth 12, 22, 44, and 46. All definitive prostheses were fabricated from zirconia ceramics, chosen for their durability and esthetic characteristics. Finally, restorations with satisfactory esthetic and functional characteristics were seated, preserving the tooth and its supporting structures. During treatment and follow-up, the T-scan occlusal analysis system was utilized to continuously monitor and guide the adjustment of occlusal distribution across the patient's dental arches. After 18 months, the patient remains satisfied with the definitive restorations. CONCLUSIONS: This report is intended to help dentists understand and implement standardized and fully digital workflows during the management of complex occlusal rehabilitation cases; it may also facilitate harmonious integration of esthetic and functional characteristics.


Assuntos
Coroas , Prótese Dentária Fixada por Implante , Estética Dentária , Humanos , Desenho Assistido por Computador , Prótese Parcial Fixa , Seguimentos , Fluxo de Trabalho
11.
Fitoterapia ; 177: 106110, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38977253

RESUMO

Six previously undescribed meroterpenoids, penicianstinoids F-K (1-6), together with four known analogues, dehydroaustinol (7), dehydroaustin (8), penicianstinoid A (9), and furanoaustinol (10), were isolated from the cultures of the algicolous fungus Penicillium sp. RR-DL-1-7, derived from the red alga Rhodomela confervoides. Their structures and relative configuration were established by detailed spectroscopic analysis of NMR and HR-MS experiments, and the absolute configurations were assigned by X-ray diffraction and ECD spectral analysis. None of the isolates showed obvious growth inhibitory effects against five plankton and four bacteria species tested.


Assuntos
Penicillium , Rodófitas , Terpenos , Penicillium/química , Estrutura Molecular , Terpenos/farmacologia , Terpenos/isolamento & purificação , Rodófitas/química , China , Bactérias/efeitos dos fármacos
12.
Chem Commun (Camb) ; 60(51): 6560-6563, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38845542

RESUMO

In this study, a Rh(III)-catalyzed C-H/N-H [4+2] annulation of oxadiazolones with iodonium ylides has been developed, which afforded a series of diverse fused-isoquinolines and fused-pyridines in moderate to high yields. These divergent synthesis protocols featured mild conditions, broad substrate scope, and functional-group compatibility. In addition, scale-up synthesis, related applications and preliminary mechanistic explorations were also accomplished.

13.
Environ Sci Technol ; 58(28): 12598-12608, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38904976

RESUMO

Understanding the transport of 137Cs emitted during the Fukushima accident is challenging because the critical emissions that produced the high-deposition area are not adequately resolved in existing source terms. This paper presents an objective inverse reconstruction of these emissions by fusing atmospheric concentrations with a-priori emissions extracted from total depositions. This extraction, previously considered impossible for complex real-world accidents, is achieved by identifying the critical temporal formation process of depositions in the high-deposition area and estimating the corresponding emissions by using an atmospheric transport model. The reconstructed source term reveals two emission peaks from 10:00-11:00 and 14:00-15:00 on March 15, which agree with the in situ pressure measurements and accident analysis, suggesting that they came from pressure drops in the primary containment vessels of Units 3 and 2, respectively. This finding explains the environmental observations of spherical 137Cs particles. The source term also objectively and independently confirms the widely used reverse estimate. The corresponding 137Cs transport simulations better match the various observations than those produced by other source terms, proving that the two-peak emission creates a high-deposition area. The proposed method outperforms the direct fusion of deposition and atmospheric concentration observations, providing a robust tool for multiobservation fusion.


Assuntos
Poluentes Radioativos do Ar , Atmosfera , Radioisótopos de Césio , Acidente Nuclear de Fukushima , Monitoramento de Radiação , Radioisótopos de Césio/análise , Poluentes Radioativos do Ar/análise , Atmosfera/química , Japão , Modelos Teóricos
15.
Int J Ophthalmol ; 17(6): 1110-1119, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895674

RESUMO

AIM: To compare high or low concentration of hyaluronic acid eye drops (HY) for dry eye syndromes (DES). METHODS: Randomized controlled trials (RCTs) comparing various concentrations of HY were searched in PubMed, Embase, Web of Science, Cochrane, SinoMed, CNKI, Wanfang Database, CQVIP, and Chinese journals databases between inception and July 2023. Pooled standardized mean differences (SMD) or weighted mean difference (WMD) with 95% confidence intervals (CI) from RCTs evaluating Schirmer's I test (SIT), corneal fluorescein staining score (CFS), tear breakup time (TBUT), DES score (DESS), and Ocular Surface Disease Index (OSDI) were calculated. Sensitivity analysis, Egger's test and Meta-regression analysis were performed for all indicators. RESULTS: We conducted a Meta-analysis of 10 RCTs that met the inclusion criteria, involving 1796 cases. High-concentrations group significantly improved the outcome of CFS according to random effects modelling (SMD, -3.37; 95%CI, -5.25 to -1.48; P=0.0005). The rest of the results were not statistically significant, including indicators such as SIT, TBUT, DESS and OSDI. CONCLUSION: For dry eyes with positive corneal staining, a high concentration of HY is recommended, whereas in other cases, a high concentration of HY does not offer a more pronounced advantage over a low concentration of HY in the treatment of dry eyes.

16.
Plant Physiol Biochem ; 213: 108823, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38905727

RESUMO

Cadmium (Cd) is a widely distributed heavy metal pollutant that is detrimental to growth and development of plants. The secretion of indole-3-acetic acid is one of the defense mechanisms when plants inflict heavy metal stress. This study aimed to explore how 4-phenoxyphenylboronic acid, an effective IAA inhibitor, induces changes in IAA level, Cadmium accumulation, and activation of defense responses in rice seedling roots under different Cadmium concentrations. Our research results show that: 1) root growth was promoted with PPBa addition under mild Cadmium treatment. 2) the root IAA level improved with increasing Cadmium concentration, and PPBa had a significant inhibitory effect on IAA level. 3) PPBa had no effect on the Cadmium accumulation in rice seedling roots. 4) PPBa had a significant inhibitory effect on the generation of H2O2 under mild and moderate Cadmium treatment. 5) PPBa exacerbated the imbalance of osmotic substances in rice seedling roots under severe Cadmium treatment. This study helps us understand the tolerance and endogenous regulation of plants to heavy metal stress.


Assuntos
Cádmio , Peróxido de Hidrogênio , Ácidos Indolacéticos , Oryza , Raízes de Plantas , Plântula , Oryza/efeitos dos fármacos , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Ácidos Indolacéticos/metabolismo , Cádmio/toxicidade , Cádmio/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Plântula/efeitos dos fármacos , Plântula/metabolismo , Plântula/crescimento & desenvolvimento , Peróxido de Hidrogênio/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Ácidos Borônicos/farmacologia
18.
J Biomater Appl ; 39(1): 48-57, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38659361

RESUMO

Electrospinning technology has recently attracted increased attention in the biomedical field, and preparing various cellulose nanofibril membranes for periodontal tissue regeneration has unique advantages. However, the characteristics of using a single material tend to make it challenging to satisfy the requirements for a periodontal barrier film, and the production of composite fibrous membranes frequently impacts the quality of the final fiber membrane due to the influence of miscibility between different materials. In this study, nanofibrous membranes composed of polylactic acid (PLA) and polycaprolactone (PCL) fibers were fabricated using side-by-side electrospinning. Different concentrations of gelatin were added to the fiber membranes to improve their hydrophilic properties. The morphological structure of the different films as well as their composition, wettability and mechanical characteristics were examined. The results show that PCL/PLA dual-fibrous composite membranes with an appropriate amount of gelatin ensures sufficient mechanical strength while obtaining improved hydrophilic properties. The viability of L929 fibroblasts was evaluated using CCK-8 assays, and cell adhesion on the scaffolds was confirmed by scanning electron microscopy and by immunofluorescence assays. The results demonstrated that none of the fibrous membranes were toxic to cells and the addition of gelatin improved cell adhesion to those membranes. Based on our findings, adding 30% gelatin to the membrane may be the most appropriate content for periodontal tissue regeneration, considering the scaffold's mechanical qualities, hydrophilic properties and biocompatibility. In addition, the PCL-gelatin/PLA-gelatin dual-fibrous membranes prepared using side-by-side electrospinning technology have potential applications for tissue engineering.


Assuntos
Adesão Celular , Fibroblastos , Gelatina , Nanofibras , Poliésteres , Alicerces Teciduais , Poliésteres/química , Gelatina/química , Nanofibras/química , Animais , Camundongos , Alicerces Teciduais/química , Linhagem Celular , Fibroblastos/citologia , Membranas Artificiais , Engenharia Tecidual , Materiais Biocompatíveis/química , Sobrevivência Celular/efeitos dos fármacos , Regeneração Tecidual Guiada Periodontal/métodos , Teste de Materiais , Regeneração
19.
Life Sci ; 346: 122637, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38614305

RESUMO

E74-like factor 3 (ELF3) is an important member of the E-twenty-six (ETS) transcription factor family. ELF3 is expressed in various types of cells and regulates a variety of biological behaviors, such as cell proliferation, differentiation, apoptosis, migration, and invasion, by binding to DNA to regulate the expression of other genes. In recent years, studies have shown that ELF3 plays an important role in the occurrence and development of many tumors and inflammation and immune related diseases. ELF3 has different functions and expression patterns in different tumors; it can function as a tumor suppressor gene or an oncogene, highlighting its dual effects of tumor promotion and inhibition. ELF3 also affects the levels of tumor immunity-related cytokines and is involved in the regulation and expression of multiple signaling pathways. In tumor therapy, ELF3 is a complex and multifunctional gene and has become a key focus of targeted treatment research. An in-depth study of the biological function of ELF3 can help to elucidate its role in biological processes and provide ideas and a basis for the development and clinical application of ELF3-related therapeutic methods. This review introduces the structure and physiological and cellular functions of the ELF3 gene, summarizes the mechanisms of action of ELF3 in different types of malignant tumors and its role in immune regulation, inflammation, etc., and discusses treatment methods for ELF3-related diseases, providing significant reference value for scholars studying the ELF3 gene and related diseases.


Assuntos
Proteínas de Ligação a DNA , Neoplasias , Fatores de Transcrição , Humanos , Neoplasias/genética , Neoplasias/patologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Ligação a DNA/genética , Animais , Proteínas Proto-Oncogênicas c-ets/genética , Proteínas Proto-Oncogênicas c-ets/metabolismo , Regulação Neoplásica da Expressão Gênica , Inflamação/genética
20.
Front Chem ; 12: 1403696, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38680457

RESUMO

The phenomenon of fire or even explosion caused by thermal runaway of lithium-ion power batteries poses a serious threat to the safety of electric vehicles. An in-depth study of the core-material thermal runaway reaction mechanism and reaction chain is a prerequisite for proposing a mechanism to prevent battery thermal runaway and enhance battery safety. In this study, based on a 24 Ah commercial Li(Ni0.6Co0.2Mn0.2)O2/graphite soft pack battery, the heat production characteristics of different state of charge (SOC) cathode and anode materials, the separator, the electrolyte, and their combinations of the battery were investigated using differential scanning calorimetry. The results show that the reaction between the negative electrode and the electrolyte is the main mode of heat accumulation in the early stage of thermal runaway, and when the heat accumulation causes the temperature to reach a certain critical value, the violent reaction between the positive electrode and the electrolyte is triggered. The extent and timing of the heat production behaviour of the battery host material is closely related to the SOC, and with limited electrolyte content, there is a competitive relationship between the positive and negative electrodes and the electrolyte reaction, leading to different SOC batteries exhibiting different heat production characteristics. In addition, the above findings are correlated with the battery failure mechanisms through heating experiments of the battery monomer. The study of the electro-thermal properties of the main materials in this paper provides a strategy for achieving early warning and suppression of thermal runaway in batteries.

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