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1.
Adv Mater ; : e2405776, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38966888

RESUMO

Bionic artificial skin which imitates the features and functions of human skin, has broad applications in wearable human-machine interfaces. However, equipping artificial materials with skin-like mechanical properties, self-healing ability, and high sensitivity remains challenging. Here, inspired by the structure of human skin, an artificial skin based on ionogel composites with tailored mechanical properties and robust interface is prepared. Combining finite element analysis and direct ink writing (DIW) 3D printing technology, an ionogel composite with a rigid skeleton and an ionogel matrix is precisely designed and fabricated, realizing the mechanical anisotropy and nonlinear mechanical response that accurately mimic human skin. Robust interface is created through co-curing of the skeleton and matrix resins, significantly enhancing the stability of the composite. The realization of self-healing ability and resistance to crack growth further ensure the remarkable durability of the artificial skin for sensing application. In summary, the bionic artificial skin mimics the characteristics of human skin, including mechanical anisotropy, nonlinear mechanical response, self-healing capability, durability and high sensitivity when applied as flexible sensors. These strategies provide strong support for the fabrication of tissue-like materials with adaptive mechanical behaviors.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38987992

RESUMO

Skin wound healing is a complex process that requires appropriate treatment and management. Using a single scaffold to dynamically manipulate angiogenesis, cell migration and proliferation, and tissue reconstruction during skin wound healing is a great challenge. We developed a hybrid scaffold platform that integrates the spatiotemporal delivery of bioactive cues with topographical cues to dynamically manipulate the wound-healing process. The scaffold comprised gelatin methacryloyl hydrogels and electrospun poly(ε-caprolactone)/gelatin nanofibers. The hydrogels had graded cross-linking densities and were loaded with two different functional bioactive peptides. The nanofibers comprised a radially aligned nanofiber array layer and a layer of random fibers. During the early stages of wound healing, the KLTWQELYQLKYKGI peptide, which mimics vascular endothelial growth factor, was released from the inner layer of the hydrogel to accelerate angiogenesis. During the later stages of wound healing, the IKVAVS peptide, which promotes cell migration, synergized with the radially aligned nanofiber membrane to promote cell migration, while the nanofiber membrane also supported further cell proliferation. In an in vivo rat skin wound-healing model, the hybrid scaffold significantly accelerated wound healing and collagen deposition, and the ratio of type I to type III collagen at the wound site resembled that of normal skin. The prepared scaffold dynamically regulated the skin tissue regeneration process in stages to achieve rapid wound repair with clinical application potential, providing a strategy for skin wound repair.

4.
Heliyon ; 10(12): e32530, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38975184

RESUMO

Cobalt has emerged as a vital material in 10 nm technology for localized interconnect layers, potentially offering a compelling alternative to Cu-based interconnects. In this study, we subjected the contamination arising from the presence of cobalt atoms in silicon to comprehensive investigation, employing electron transmission electron microscopy (TEM) observations in conjunction with first-principles calculations. The results show that a dense CoSi layer with a thickness of a few nanometers is formed at the interface of cobalt and Si. The CoSi layer blocks the diffusion of Co atoms into Si. This is due to the semiconducting nature of the covalent bond formed between Co and Si, leading to the emergence of a forbidden zone at the Co/CoSi interface. The diffusion of Co into CoSi is governed by the atomic exchange mechanism, however, the local distortion of the periodic atomic potential due to the presence of the forbidden zone at the Co/CoSi interface hinders the diffusion of Co into Si. Therefore, the deposition of a Co metal layer on a Si chip does not require an additional barrier layer.

6.
Plant Biotechnol J ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39024420

RESUMO

Cold stress is a major abiotic stress that threatens maize (Zea mays L.) production worldwide. Understanding the molecular mechanisms underlying cold tolerance is crucial for breeding resilient maize varieties. Tonoplast intrinsic proteins (TIPs) are a subfamily of aquaporins in plants. Here, we report that TIP family proteins are involved in maize cold tolerance. The expression of most TIP genes was responsive to cold stress. Overexpressing TIP2;1, TIP3;2 or TIP4;3 reduced the cold tolerance of maize seedlings, while loss-of-function mutants of TIP4;3 exhibited enhanced cold tolerance. Candidate gene-based association analysis revealed that a 328-bp transposon insertion in the promoter region of TIP4;3 was strongly associated with maize cold tolerance. This transposon insertion conferred cold tolerance by repressing TIP4;3 expression through increased methylation of its promoter region. Moreover, TIP4;3 was found to suppress stomatal closure and facilitate reactive oxygen species (ROS) accumulation under cold stress, thereby inhibiting the expression of cold-responsive genes, including DEHYDRATION-RESPONSIVE ELEMENT BINDING FACTOR 1 (DREB1) genes and a subset of peroxidase genes, ultimately attenuating maize cold tolerance. This study thus elucidates the mechanism underlying TIP-mediated cold tolerance and identifies a favourable TIP4;3 allele as a potential genetic resource for breeding cold-tolerant maize varieties.

7.
J Colloid Interface Sci ; 674: 326-335, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38936089

RESUMO

The rational design of catalysts with atomic dispersion and a deep understanding of the catalytic mechanism is crucial for achieving high performance in CO2 reduction reaction (CO2RR). Herein, we present an atomically dispersed electrocatalyst with single Cu atom and atomic Ni clusters supported on N-doped mesoporous hollow carbon sphere (CuSANiAC/NMHCS) for highly efficient CO2RR. CuSANiAC/NMHCS demonstrates a remarkable CO Faradaic efficiency (FECO) exceeding 90% across a potential range of -0.6 to -1.2 V vs. reversible hydrogen electrode (RHE) and achieves its peak FECO of 98% at -0.9 V vs. RHE. Theoretical studies reveal that the electron redistribution and modulated electronic structure-notably the positive shift in d-band center of Ni 3d orbital-resulting from the combination of single Cu atom and atomic Ni clusters markedly enhance the CO2 adsorption, facilitate the formation of *COOH intermediate, and thus promote the CO production activity. This study offers fresh perspectives on fabricating atomically dispersed catalysts with superior CO2RR performance.

8.
Behav Brain Res ; 471: 115098, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38871128

RESUMO

OBJECTIVE: Depression can impact the severity of rheumatoid arthritis (RA). This study aimed to investigate the relationship between Th1, Th2, Th17, Treg cell subsets, and their associated cytokines (e.g., IL-2, IL-4, IL-6, IL-10, IL-17, IFN-γ, and TNF-α), and the occurrence of RA both with and without comorbid depression. The objective is to identify potential biological markers, therapeutic targets, and the therapeutic effects of RA with comorbid depression. RESULTS: 53 RA patients,46 RA with comorbid depression patients and 51 healthy subjects were included in the RA,RD and HC group from August 2021 and October 2022. Among RA patients, 46.46 % were comorbid with depression. IL-6 concentrations were significantly higher in RD group than in RA group.Comparison between the HC and RA and RD groups revealed that Th1 %, Th17 %, Th1, Th17, Th1/Th2, Th17/Treg and Th1/Treg were significantly higher in the RA and RD groups, and conversely, Th2 %, Treg%, Th2 and Treg were significantly lower than in the HC group.The RA group compared to the RD group found that Th17 %, Th17 and Th17/Treg were significantly higher in the RD group than in the RA group, however, Th1 %, Treg and Th2/Treg were significantly lower than in the RA group. The total HAMD score had a medium strength positive correlation with IL-6. CONCLUSION: These findings suggest that elevated the autoimmunity status was overactivated in RA with or without depression activates patients, IL-6 may be a predictor of the severity of RA with comorbid depression, IL-6 concentrations and an imbalance in the Th17/Treg may underlie the comorbidity of RA and depression, offering potential targets for therapeutic intervention, prompting further evaluation of the role of indirect inflammatory markers in RA with comorbid depression, highlighting the need for additional research to clarify the complex relationship between inflammation and psychological health.

9.
Angew Chem Int Ed Engl ; : e202408996, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38873975

RESUMO

Two-dimensional Ti3C2Tx MXene materials, with metal-like conductivities and versatile terminals, have been considered to be promising surface modification materials for Zn-metal-based aqueous batteries (ZABs). However, the oxygen-rich and hybridized terminations caused by conventional methods limit their advantages in inhibiting zinc dendrite growth and reducing corrosion-related side reactions. Herein, -O-depleted, -Cl-terminated Ti3C2Tx was precisely fabricated by the molten salt electrochemical etching of Ti3AlC2, and controlled in-situ terminal replacement from -Cl to unitary -S or -Se was achieved. The as-prepared -O-depleted and unitary-terminal Ti3C2Tx as Zn anode coatings provided excellent hydrophobicity and enriched zinc-ionophilic sites, facilitating Zn2+ horizontal transport for homogeneous deposition and effectively suppressing water-induced side reactions. The as-assembled Ti3C2Sx@Zn symmetric cell achieved a cycle life of up to 4200 h at a current density and areal capacity of 2 mA cm-2 and 1 mAh cm-2, respectively, with an impressive cumulative capacity of up to 7.25 Ah cm-2 at 5 mA cm-2 // 2 mAh cm-2. These findings provide an effective electrochemical strategy for tailoring -O-depleted and unitary Ti3C2Tx surface terminals and advancing the understanding of the role of specific Ti3C2Tx surface chemistry in regulating the plating/stripping behaviors of metal ions.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38847244

RESUMO

PURPOSE: This study aimed to clarify the expression of a gene associated with Retinoid- Interferon-Induced Mortality-19 (GRIM-19) in Upper Urinary Tract Urothelial Carcinoma (UUTUC) and its prognostic significance for UUTUC patients. MATERIALS AND METHODS: Immunohistochemical (IHC) staining was used to determine the GRIM-19 expression in 70 paired samples. Progression-Free Survival (PFS) and Cancer-Specific Survival (CSS) were assessed using the Kaplan-Meier method. The independent prognostic factors for PFS and CSS were analyzed by multivariable Cox regression models. RESULTS: IHC staining showed that GRIM-19 expression was significantly decreased in UUTUC, and its cellular location changed from being both cytoplasmic and nuclear to only cytoplasmic. Kaplan- Meier analysis revealed that the patients with tumors expressing low GRIM-19 had a significantly higher risk for tumor progression (P = 0.002) and cancer-specific mortality (P < 0.001) compared to those with high GRIM-19 levels. The Cox regression showed that both GRIM-19 expression (P = 0.025) and lymph node metastasis (LN) (P = 0.007) were independent predictors of progression in the muscle-invasive (MIC) subgroup. GRIM-19 expressions (entire cohort: P = 0.011; MIC subgroup: P = 0.025), LN (entire cohort: P = 0.019; MIC subgroup: P = 0.007), and progression (entire cohort: P < 0.001; MIC subgroup: P < 0.001) were independent predictors of cancer-specific survival. CONCLUSION: Low expression of GRIM-19 in patients with UUTUC had significantly shorter PFS or CSS compared to those with high GRIM-19-expressing tumors. High GRIM-19 expression was also strongly associated with longer PFS in MIC patients. It indicates that GRIM-19 might serve as a promising prognostic biomarker for UUTUC patients.

11.
Front Vet Sci ; 11: 1340591, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38846786

RESUMO

Objective: Orchitis is a common reproductive disease of male animals, which has serious implications to human and animal reproduction. Additionally, phlorizin (PHN), a common polyphenol in apples and strawberries, has a variety of biological activities, including antioxidant, anti-inflammatory, anti-diabetic, and anti-aging activities. We aimed to determine the protective effects and potential mechanisms of PHN in lipopolysaccharide (LPS)-induced acute orchitis in mice. Method: After 21 days of PHN pretreatment, mice were injected with LPS to induce testicular inflammation, and then the changes of testicular tissue structure, expression of inflammatory factors, testosterone level, expression of testosterone-related genes, adhesion gene and protein expression were detected, and the structural changes in the intestinal flora after PHN treatment were further detected by 16SRNA. Result: Our results demonstrated that PHN treatment reduced LPS-induced testicular injury and body and testicular weight losses. The mRNA expression levels of pro-inflammatory cytokines-related genes and antioxidant enzyme activity were also decreased and elevated, respectively, by PHN administration; however, PHN treatment also reduced the LPS-induced decrease in testosterone levels in the testes. Additionally, further studies found that PHN increased the expression of marker proteins zonula occludens-1 (ZO-1) and occludin associated with the blood testosterone barrier compared with that in LPS treatment groups. To further examine the potential mechanisms of the protective effect of PHN on LPS-induced testicular injury, we compared the differences of gut microbiota compositions between the 100 mg/kg PHN treatment group and the control group using 16SRNA. Metagenomic analyses indicated that the abundances of Bacteroidetes, Muribaculaceae, Lactobacillaceae, uncultured bacterium f Muribaculaceae, and Lactobacillus in the PHN treatment group improved, while potential microbes that can induce intestinal diseases, including Verrucomicrobia, Epsilonbacteraeota, Akkermansiaceae, and Akkermansia decreased in the PHN treatment group. Conclusion: Our results indicate that PHN pretreatment might alleviate orchitis by altering the composition of gut microflora, which may provide a reference for reducing the occurrence of acute orchitis in male animals.

12.
Nature ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38866052

RESUMO

Increasing planting density is a key strategy to enhance maize yields1-3. An ideotype for dense planting requires a 'smart canopy' with leaf angles at different canopy layers differentially optimized to maximize light interception and photosynthesis4-6, amongst other features. Here, we identified leaf angle architecture of smart canopy 1 (lac1), a natural mutant possessing upright upper leaves, less erect middle leaves and relatively flat lower leaves. lac1 has improved photosynthetic capacity and weakened shade-avoidance responses under dense planting. lac1 encodes a brassinosteroid C-22 hydroxylase that predominantly regulates upper leaf angle. Phytochrome A photoreceptors accumulate in shade and interact with the transcription factor RAVL1 to promote its degradation via the 26S proteasome, thereby attenuating RAVL1 activation of lac1 and reducing brassinosteroid levels. This ultimately decreases upper leaf angle in dense fields. Large-scale field trials demonstrate lac1 boosts maize yields under high densities. To quickly introduce lac1 into breeding germplasm, we transformed a haploid inducer and recovered homozygous lac1 edits from 20 diverse inbred lines. The tested doubled haploids uniformly acquired smart-canopy-like plant architecture. We provide an important target and an accelerated strategy for developing high-density-tolerant cultivars, with lac1 serving as a genetic chassis for further engineering of a smart canopy in maize.

13.
Gastroenterol Rep (Oxf) ; 12: goae051, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38855349

RESUMO

Background: The optimal regimen of infliximab salvage in acute severe ulcerative colitis (ASUC) patients remains controversial. This study aimed to compare accelerated and standard infliximab induction in Chinese ASUC patients, and to explore risk factors and concrete accelerated regimens for them. Methods: Data were retrospectively collected from steroid-refractory ASUC patients receiving infliximab as rescue therapy at seven tertiary centers across China. Outcomes including colectomy and clinical remission (Mayo score ≤ 2 and every subscore ≤ 1 at Day 14) rates were compared between patients receiving accelerated and standard infliximab induction using propensity score adjustment for potential confounders. The dose-response relationship was explored by plotting restricted cubic splines. Logistic regression and Cox proportional hazards regression analyses were performed to determine risk factors for adverse outcomes. A systematic review and meta-analysis was also performed. Results: A total of 76 patients were analysed: 29 received standard and 47 received accelerated induction. The accelerated group had a higher 90-day colectomy rate (17.8% vs 0%, P = 0.019) and lower clinical remission rate (27.7% vs 65.5%, P = 0.001). After adjusting for propensity score and institution, there was no significant difference in colectomy or clinical remission rates (both P > 0.05). Dose-effect curves showed decreased colectomy hazard with higher cumulative infliximab dosage within 5 days, with no improvement observed for increasing cumulative infliximab dosage within 28 days. Multivariate logistic regression analyses revealed C-reactive protein of >10 mg/L at infliximab initiation (odds ratio = 5.00, 95% confidence interval: 1.27-24.34) as an independent risk factor for no clinical remission. Meta-analysis also revealed no significant difference in colectomy rates at 3 months (P = 0.54). Conclusions: After adjusting for confounders, there were no significant differences in colectomy or clinical remission rates between accelerated and standard infliximab induction among ASUC patients. Early administration of an intensified dosage within 5 days may be beneficial. Elevated C-reactive protein at infliximab initiation indicated need for intensive treatment.

14.
Mil Med Res ; 11(1): 35, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38835066

RESUMO

Neuroendocrine neoplasms (NENs) are highly heterogeneous and potentially malignant tumors arising from secretory cells of the neuroendocrine system. Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are the most common subtype of NENs. Historically, GEP-NENs have been regarded as infrequent and slow-growing malignancies; however, recent data have demonstrated that the worldwide prevalence and incidence of GEP-NENs have increased exponentially over the last three decades. In addition, an increasing number of studies have proven that GEP-NENs result in a limited life expectancy. These findings suggested that the natural biology of GEP-NENs is more aggressive than commonly assumed. Therefore, there is an urgent need for advanced researches focusing on the diagnosis and management of patients with GEP-NENs. In this review, we have summarized the limitations and recent advancements in our comprehension of the epidemiology, clinical presentations, pathology, molecular biology, diagnosis, and treatment of GEP-NETs to identify factors contributing to delays in diagnosis and timely treatment of these patients.


Assuntos
Tumores Neuroendócrinos , Neoplasias Pancreáticas , Neoplasias Gástricas , Humanos , Tumores Neuroendócrinos/terapia , Tumores Neuroendócrinos/epidemiologia , Tumores Neuroendócrinos/diagnóstico , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/terapia , Neoplasias Gástricas/diagnóstico , Neoplasias Intestinais/terapia , Neoplasias Intestinais/epidemiologia , Neoplasias Intestinais/diagnóstico
15.
BMC Public Health ; 24(1): 1555, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858655

RESUMO

OBJECTIVES: Acute upper respiratory tract infections (AURTIs) are prevalent in the general population. However, studies on the association of short-term exposure to air pollution with the risk of hospital visits for AURTIs in adults are limited. This study aimed to explore the short-term exposure to air pollutants among Chinese adults living in Ningbo. METHODS: Quasi-Poisson time serious regressions with distributed lag non-linear models (DLNM) were applied to explore the association between ambient air pollution and AURTIs cases. Patients ≥ 18 years who visit three hospitals, being representative for urban, urban-rural junction and rural were included in this retrospective study. RESULTS: In total, 104,441 cases with AURTIs were enrolled in hospital during 2015-2019. The main results showed that particulate matter with an aerodynamic diameter less than 2.5 µm (PM2.5), nitrogen dioxide (NO2) and nitrogen dioxide (SO2), were positively associated to hospital visits for AURTIs, except for nitrogen dioxide (O3), which was not statistically significant. The largest single-lag effect for PM2.5 at lag 8 days (RR = 1.02, 95%CI: 1.08-1.40), for NO2 at lag 13 days (RR = 1.03, 95%CI: 1.00-1.06) and for SO2 at lag 5 days (RR = 1.27, 95%CI: 1.08-1.48), respectively. In the stratified analysis, females, and young adults (18-60 years) were more vulnerable to PM2.5 and SO2 and the effect was greater in rural areas and urban-rural junction. CONCLUSIONS: Exposure to ambient air pollution was significantly associated with hospital visits for AURTIs. This study provides epidemiological evidence for policymakers to control better air quality and establish an enhanced system of air pollution alerts.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Exposição Ambiental , Material Particulado , Infecções Respiratórias , Humanos , China/epidemiologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/etiologia , Estudos Retrospectivos , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Material Particulado/análise , Material Particulado/efeitos adversos , Exposição Ambiental/efeitos adversos , Exposição Ambiental/estatística & dados numéricos , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Idoso , Adulto Jovem , Hospitalização/estatística & dados numéricos , Adolescente , Fatores de Tempo , Doença Aguda , Dióxido de Nitrogênio/análise , Dióxido de Nitrogênio/efeitos adversos
16.
Sensors (Basel) ; 24(11)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38894221

RESUMO

Aiming at the problems of incomplete dehazing, color distortion, and loss of detail and edge information encountered by existing algorithms when processing images of underground coal mines, an image dehazing algorithm for underground coal mines, named CAB CA DSConv Fusion gUNet (CCDF-gUNet), is proposed. First, Dynamic Snake Convolution (DSConv) is introduced to replace traditional convolutions, enhancing the feature extraction capability. Second, residual attention convolution blocks are constructed to simultaneously focus on both local and global information in images. Additionally, the Coordinate Attention (CA) module is utilized to learn the coordinate information of features so that the model can better capture the key information in images. Furthermore, to simultaneously focus on the detail and structural consistency of images, a fusion loss function is introduced. Finally, based on the test verification of the public dataset Haze-4K, the Peak Signal-to-Noise Ratio (PSNR), Structural Similarity (SSIM), and Mean Squared Error (MSE) are 30.72 dB, 0.976, and 55.04, respectively, and on a self-made underground coal mine dataset, they are 31.18 dB, 0.971, and 49.66, respectively. The experimental results show that the algorithm performs well in dehazing, effectively avoids color distortion, and retains image details and edge information, providing some theoretical references for image processing in coal mine surveillance videos.

17.
Huan Jing Ke Xue ; 45(6): 3562-3570, 2024 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-38897776

RESUMO

Studying the effects of different modified materials on the physicochemical properties and fungal community structure of saline-alkali soil can provide theoretical basis for reasonable improvement of saline-alkali soil. High-throughput sequencing technology was used to explore the effects of five treatments, namely, control (CK), desulfurization gypsum (T1), soil ameliorant (T2), organic fertilizer (T3), and desulfurization gypsum compounds soil ameliorant and organic fertilizer (T4), on soil physicochemical properties and fungal community diversity, composition, and structure of saline-alkali soil in Hetao Plain, Inner Mongolia. The results showed that compared with those in CK, the contents of available phosphorus, available potassium, organic matter, and alkali hydrolysis nitrogen were significantly increased in modified material treatments, and the T4 treatment significantly decreased soil pH. Modified treatments increased the Simpson and Shannon indexes of fungi but decreased the Chao1 index. The dominant fungi were Ascomycota, Basidiomycota, and Mortierellomycota, and the dominant genera were Mortierella, Conocybe, Botryotrichum, Fusarium, and Pseudogymnoascus. The application of modified materials increased the relative abundance of Ascomycota, Basidiomycota, Fusarium, and Pseudogymnoascus, while decreasing the relative abundance of Mortierellomycota, Chytridiomycota, and Mortierella. LEfSe analysis showed that modified treatments altered the fungal community biomarkers. Correlation analysis showed that pH and available potassium were the main environmental factors affecting fungal community structure. The results can provide scientific basis for improving saline-alkali soil and increasing soil nutrients in Hetao Plain, Inner Mongolia.


Assuntos
Álcalis , Fungos , Microbiologia do Solo , Solo , Solo/química , Fungos/classificação , Álcalis/química , China , Fertilizantes , Dinâmica Populacional , Micobioma , Ascomicetos , Basidiomycota , Salinidade
18.
Nat Commun ; 15(1): 5215, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890339

RESUMO

Stretching elastic materials containing nanoparticle lattices is common in research and industrial settings, yet our knowledge of the deformation process remains limited. Understanding how such lattices reconfigure is critically important, as changes in microstructure lead to significant alterations in their performance. This understanding has been extremely difficult to achieve due to a lack of fundamental rules governing the rearrangements. Our study elucidates the physical processes and underlying mechanisms of three-dimensional lattice transformations in a polymeric photonic crystal from 0% to over 200% strain during uniaxial stretching. Corroborated by comprehensive experimental characterizations, we present analytical models that precisely predict both the three-dimensional lattice structures and the macroscale deformations throughout the stretching process. These models reveal how the nanoparticle lattice and matrix polymer jointly determine the resultant structures, which breaks the original structural symmetry and profoundly changes the dispersion of photonic bandgaps. Stretching induces shifting of the main pseudogap structure out from the 1st Brillouin zone and the merging of different symmetry points. Evolutions of multiple photonic bandgaps reveal potential optical singularities shifting with strain. This work sets a new benchmark for the reconfiguration of soft material structures and may lay the groundwork for the study of stretchable three-dimensional topological photonic crystals.

19.
J Asian Nat Prod Res ; : 1-17, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829012

RESUMO

Spirotryprostatins are representative members of medicinally interesting bioactive molecules of the spirooxindole natural products. In this communication, we present a novel enantioselective total synthesis of the spirooxindole alkaloid dihydrospirotryprostatin B. The synthesis takes advantage of copper-catalyzed tandem reaction of o-iodoanilide chiral sulfinamide derivatives with alkynone to rapidly construct the key quaternary carbon stereocenter of the natural product dihydrospirotryprostatin B.

20.
Hepatobiliary Surg Nutr ; 13(3): 494-499, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38911193

RESUMO

Laparoscopic anatomical hepatectomy (LAH) for patients with hepatocellular carcinoma (HCC) has been advocated by many surgeons in the hope of producing better oncological outcomes. Two recent techniques, 3D laparoscopic system and 2D real-time indocyanine green fluorescence imaging (r-ICG) guidance, are benefit for improving the operative precision of LAH in different aspects. However, these two techniques cannot be applied concomitantly because of the technical limitation. Although a new modern laparoscopic system with both 3D and indocyanine green (ICG) imaging mode has been designed, it has not been listed in many countries including China. Thus, we design a new procedure to perform the 3D LAH with 2D r-ICG guidance for HCCs with conventional laparoscopic systems. In this procedure, both 3D and 2D laparoscopic systems were used. A total of 11 patients with HCC received 3D laparoscopic right posterior sectionectomy (LRPS) with 2D r-ICG guidance. The right posterior Glissonian pedicle was clamped under the 3D vision. Then ICG solution was then intravenously administrated. The liver parenchyma was transected under the 3D vision and guided by 2D ICG vision simultaneously. There was no severe complications (Clavien-Dindo ≥III) and operation related death. The 90-day mortality was also nil. By using this procedure, the advantages of two techniques, 3D laparoscopic system and 2D r-ICG guidance, were combined so that LAH could be performed with more precision. However, it should be validated in more studies.

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