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1.
Chem Commun (Camb) ; 60(52): 6631-6634, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38853589

RESUMO

We found that the interfacially confined self-assembly of pyrene and phenanthrene glutamides can form strong exciplexes and amorphous superhelices, which show intensity-enhanced and sign-inverted CPL activity with improved quantum yield compared to a pyrene excimer. This work unveils the predominant role of supramolecular nanostructures over molecular configurations on CPL performance.

2.
Ultrasonics ; 141: 107338, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38723293

RESUMO

Recently, the moiré pattern has attracted lots of attention by superimposing two planar structures of regular geometries, such as two sets of metasurfaces or gratings. Here, we show the experimental investigation of acoustic moiré effect by using twisted bilayer gratings (i.e., one grating twisted with respect to the other). We observed the guided resonance that occurred when the incident ultrasound beam was coupled with the guiding modes in a meta-grating, significantly influencing the reflection and transmission. Tunable guided resonances from the moiré effect with complete ultrasound reflection at different frequencies were further demonstrated in experiments. Combining the measurements of transmission spectra and the Fast Fourier Transform analyses, we reveal the guided resonance frequencies of moiré ultrasonic metasurface can be effectively controlled by adjusting the twisting angle of the bilayer gratings. Our results can be explained in a simplified model based on the band folding theory, providing a reliable prediction on the precise control of ultrasound reflection via the twisting angle adjustment. Our work extends the moiré metasurface from optics into acoustics, which shows more possibilities for the ultrasound beam engineering from the moiré effect and enables the exploration of functional acoustic devices for ultrasound imaging, treatment and diagnosis.

3.
Phys Rev Lett ; 132(19): 197202, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38804947

RESUMO

The higher-order topological phases have attracted intense attention in the past years, which reveals various intriguing topological properties. Meanwhile, the enrichment of group symmetries with projective symmetry algebras redefines the fundamentals of topological matter and makes Stiefel-Whitney (SW) classes in classical wave systems possible. Here, we report the experimental realization of higher-order topological nodal loop semimetal in an acoustic system and obtain the inherent SW topological invariants. In stark contrast to higher-order topological semimetals relating to complex vector bundles, the hinge and surface states in the SW topological phase are protected by two distinctive SW topological charges relevant to real vector bundles. Our findings push forward the studies of SW class topology in classical wave systems, which also show possibilities in robust high-Q-resonance-based sensing and energy harvesting.

4.
Nat Commun ; 15(1): 4346, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773182

RESUMO

Narrow bandwidths are a general bottleneck for applications relying on passive, linear, subwavelength resonators. In the past decades, several efforts have been devoted to overcoming this challenge, broadening the bandwidth of small resonators by the means of analog non-Foster matching networks for radiators, antennas and metamaterials. However, most non-Foster approaches present challenges in terms of tunability, stability and power limitations. Here, by tuning a subwavelength acoustic transducer with digital non-Foster-inspired electronics, we demonstrate five-fold bandwidth enhancement compared to conventional analog non-Foster matching. Long-distance transmission over airborne acoustic channels, with approximately three orders of magnitude increase in power level, validates the performance of the proposed approach. We also demonstrate convenient reconfigurability of our non-Foster-inspired electronics. This implementation provides a viable solution to enhance the bandwidth of sub-wavelength resonance-based systems, extendable to the electromagnetic domain, and enables the practical implementation of airborne and underwater acoustic radiators.

5.
J Radiat Res ; 65(3): 279-290, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38682896

RESUMO

Combined radiation-trauma skin injury represents a severe and intractable condition that urgently requires effective therapeutic interventions. In this context, hepatocyte growth factor (HGF), a multifunctional growth factor with regulating cell survival, angiogenesis, anti-inflammation and antioxidation, may be valuable for the treatment of combined radiation-trauma injury. This study investigated the protective effects of a recombinant plasmid encoding human HGF (pHGF) on irradiated human immortalized keratinocytes (HaCaT) cells in vitro, and its capability to promote the healing of combined radiation-trauma injuries in mice. The pHGF radioprotection on irradiated HaCaT cells in vitro was assessed by cell viability, the expression of Nrf2, Bcl-2 and Bax, as well as the secretion of inflammatory cytokines. In vivo therapeutic treatment, the irradiated mice with full-thickness skin wounds received pHGF local injection. The injuries were appraised based on relative wound area, pathology, immunohistochemical detection, terminal deoxynucleotidyl transferase dUTP nick end labelling assay and cytokine content. The transfection of pHGF increased the cell viability and Nrf2 expression in irradiated HaCaT cells. pHGF also significantly upregulated Bcl-2 expression, decreased the Bax/Bcl-2 ratio and inhibited the expression of interleukin-1ß and tumor necrosis factor-α in irradiated cells. Local pHGF injection in vivo caused high HGF protein expression and noticeable accelerated healing of combined radiation-trauma injury. Moreover, pHGF administration upregulated Nrf2, vascular endothelial growth factor, Bcl-2 expression, downregulated Bax expression and mitigated inflammatory response. In conclusion, the protective effect of pHGF may be related to inhibiting apoptosis and inflammation involving by upregulating Nrf2. Local pHGF injection distinctly promoted the healing of combined radiation-trauma injury and demonstrates potential as a gene therapy intervention for combined radiation-trauma injury in clinic.


Assuntos
Fator de Crescimento de Hepatócito , Fator 2 Relacionado a NF-E2 , Plasmídeos , Transdução de Sinais , Pele , Cicatrização , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Humanos , Fator de Crescimento de Hepatócito/genética , Cicatrização/efeitos dos fármacos , Pele/patologia , Pele/efeitos da radiação , Camundongos , Lesões por Radiação , Apoptose , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Citocinas/metabolismo , Células HaCaT , Masculino , Queratinócitos/efeitos da radiação
6.
Sci Total Environ ; 927: 172064, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38569968

RESUMO

Soil parent material is the second most influential factor in pedogenesis, influencing soil properties and microbial communities. Different assembly processes shape diverse functional microbial communities. The question remains unresolved regarding how these ecological assembly processes affect microbial communities and soil functionality within soils on different parent materials. We collected soil samples developed from typical parent materials, including basalt, granite, metamorphic rock, and marine sediments across soil profiles at depths of 0-20, 20-40, 40-80, and 80-100 cm, within rubber plantations on Hainan Island, China. We determined bacterial community characteristics, community assembly processes, and soil enzyme-related functions using 16S rRNA high-throughput sequencing and enzyme activity analyses. We found homogeneous selection, dispersal limitation, and drift processes were the dominant drivers of bacterial community assembly across soils on different parent materials. In soils on basalt, lower pH and higher moisture triggered a homogeneous selection-dominated assembly process, leading to a less diverse community but otherwise higher carbon and nitrogen cycling enzyme activities. As deterministic process decreased, bacterial community diversity increased with stochastic process. In soils on marine sediments, lower water, carbon, and nutrient content limited the dispersal of bacterial communities, resulting in higher community diversity and an increased capacity to utilize relative recalcitrant substrates by releasing more oxidases. The r-strategy Bacteroidetes and genera Sphingomonas, Bacillus, Vibrionimonas, Ochrobactrum positively correlated with enzyme-related function, whereas k-strategy Acidobacteria, Verrucomicrobia and genera Acidothermus, Burkholderia-Caballeronia-Paraburkholderia, HSB OF53-F07 showed negative correlations. Our study suggests that parent material could influence bacterial community assembly processes, diversity, and soil enzyme-related functions via soil properties.


Assuntos
Bactérias , Microbiota , Microbiologia do Solo , Solo , Solo/química , China , RNA Ribossômico 16S , Biodiversidade
7.
Sci Adv ; 10(16): eadn1746, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640240

RESUMO

Phase modulation has scarcely been mentioned in diffusive physical systems because the diffusion process does not carry the momentum like waves. Recently, non-Hermitian physics provides a unique perspective for understanding diffusion and shows prospects in thermal phase regulation, exemplified by the discovery of anti-parity-time (APT) symmetry in diffusive systems. However, precise control of thermal phase remains elusive hitherto and can hardly be realized, due to the phase oscillations. Here we construct the PT-symmetric diffusive systems to achieve the complete suppression of thermal phase oscillation. The real coupling of diffusive fields is readily established through a strong convective background, and the decay-rate detuning is enabled by thermal metamaterial design. We observe the phase transition of PT symmetry breaking with the symmetry-determined amplitude and phase regulation of coupled temperature fields. Our work shows the existence of PT symmetry in dissipative energy exchanges and provides unique approaches for harnessing the mass transfer of particles, wave dynamics in strongly scattering systems, and thermal conduction.

8.
Ying Yong Sheng Tai Xue Bao ; 35(1): 102-110, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38511446

RESUMO

Microorganisms are essential actors in the biogeochemical cycling of elements within terrestrial ecosystems, with significant influences on soil health, food security, and global climate change. The contribution of microbial anabolism-induced organic compounds is a non-negligible factor in the processes associated with soil carbon (C) storage and organic matter preservation. In recent years, the conceptual framework of soil microbial carbon pump (MCP), with a focus on microbial metabolism and necromass generation process, has gained widespread attention. It primarily describes the processes of soil organic C formation and stabilization driven by the metabolic activities of soil heterotrophic microorganisms, representing an important mechanism and a focal point in current research on terrestrial C sequestration. Here, we reviewed the progress in this field and introduced the soil MCP conceptual framework 2.0, which expands upon the existing MCP model by incorporating autotrophic microbial pathway for C sequestration and integrating the concept of soil mineral C pump. These advancements aimed to enrich and refine our understanding of microbial-mediated terrestrial ecosystem C cycling and sequestration mechanisms. This refined framework would provide theoretical support for achieving China's "dual carbon" goals.


Assuntos
Carbono , Ecossistema , Carbono/química , Solo/química , Microbiologia do Solo , Ciclo do Carbono , Sequestro de Carbono
9.
Sci Bull (Beijing) ; 69(9): 1228-1236, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38503653

RESUMO

The paradigm shift of Hermitian systems into the non-Hermitian regime profoundly modifies inherent property of the topological systems, leading to various unprecedented effects such as the non-Hermitian skin effect (NHSE). In the past decade, the NHSE has been demonstrated in quantum, optical and acoustic systems. Beside those wave systems, the NHSE in diffusive systems has not yet been observed, despite recent abundant advances in the study of topological thermal diffusion. In this work, we design a thermal diffusion lattice based on a modified Su-Schrieffer-Heeger model and demonstrate the diffusive NHSE. In the proposed model, the asymmetric temperature field coupling inside each unit cell can be judiciously realized by appropriate configurations of structural parameters. We find that the temperature fields trend to concentrate toward the target boundary which is robust against initial excitation conditions. We thus experimentally demonstrated the NHSE in thermal diffusion and verified its robustness against various defects. Our work provides a platform for exploration of non-Hermitian physics in the diffusive systems, which has important applications in efficient heat collection, highly sensitive thermal sensing and others.

10.
Nat Commun ; 15(1): 1478, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368404

RESUMO

For classical waves, phase matching is vital for enabling efficient energy transfer in many scenarios, such as waveguide coupling and nonlinear optical frequency conversion. Here, we propose a temporal quasi-phase matching method and realize robust and complete acoustical energy transfer between arbitrarily detuned cavities. In a set of three cavities, A, B, and C, the time-varying coupling is established between adjacent elements. Analogy to the concept of stimulated Raman adiabatic passage, amplitudes of the two couplings are modulated as time-delayed Gaussian functions, and the couplings' signs are periodically flipped to eliminate temporal phase mismatching. As a result, robust and complete acoustic energy transfer from A to C is achieved. The non-reciprocal frequency conversion properties of our design are demonstrated. Our research takes a pivotal step towards expanding wave steering through time-dependent modulations and is promising to extend the frequency conversion based on state evolution in various linear Hermitian systems to nonlinear and non-Hermitian regimes.

11.
Adv Mater ; 36(23): e2312421, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38386009

RESUMO

The discovery of higher-order topological insulator metamaterials, in analogy with their condensed-matter counterparts, has enabled various breakthroughs in photonics, mechanics, and acoustics. A common way of inducing higher-order topological wave phenomena is through pseudo-spins, which mimic the electron spins as a symmetry-breaking degree of freedom. Here, this work exploits degenerate orbitals in acoustic resonant cavities to demonstrate versatile, orbital-selective, higher-order topological corner states. Type-II corner states are theoretically investigated and experimentally demonstrated based on tailored orbital interactions, without the need for long-range hoppings that has so far served as a key ingredient for Type-II corner states in single-orbital systems. Due to the orthogonal nature of the degenerate p orbitals, this work also introduces a universal strategy to realize orbital-dependent edge modes, featuring high-Q edge states identified in bulk bands. These findings provide an understanding of the interplay between acoustic orbitals and topology, shedding light on orbital-related topological wave physics, as well as its applications for acoustic sensing and trapping.

12.
Curr Drug Deliv ; 21(5): 763-774, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37157191

RESUMO

BACKGROUND: Most patients who undergo radiotherapy develop radiation skin injury, for which effective treatment is urgently needed. MnSOD defends against reactive oxygen species (ROS) damage and may be valuable for treating radiation-induced injury. Here, we (i) investigated the therapeutic and preventive effects of local multiple-site injections of a plasmid, encoding human MnSOD, on radiation-induced skin injury in rats and (ii) explored the mechanism underlying the protective effects of pMnSOD. METHODS: The recombinant plasmid (pMnSOD) was constructed with human cytomegalovirus (CMV) promoter and pUC-ori. The protective effects of pMnSOD against 20-Gy X-ray irradiation were evaluated in human keratinocytes (HaCaT cells) by determining cell viability, ROS levels, and ferroptosisrelated gene expression. In therapeutic treatment, rats received local multiple-site injections of pMnSOD on days 12, 19, and 21 after 40-Gy γ-ray irradiation. In preventive treatment, rats received pMnSOD injections on day -3 pre-irradiation and on day 4 post-irradiation. The skin injuries were evaluated based on the injury score and pathological examination, and ferroptosis-related gene expression was determined. RESULTS: In irradiated HaCaT cells, pMnSOD transfection resulted in an increased SOD2 expression, reduced intracellular ROS levels, and increased cell viability. Moreover, GPX4 and SLC7A11 expression was significantly upregulated, and erastin-induced ferroptosis was inhibited in HaCaT cells. In the therapeutic and prevention treatment experiments, pMnSOD administration produced local SOD protein expression and evidently promoted the healing of radiation-induced skin injury. In the therapeutic treatment experiments, the injury score in the high-dose pMnSOD group was significantly lower than in the PBS group on day 33 post-irradiation (1.50 vs. 2.80, P < 0.05). In the prevention treatment experiments, the skin injury scores were much lower in the pMnSOD administration groups than in the PBS group from day 21 to day 34. GPX4, SLC7A11, and Bcl-2 were upregulated in irradiated skin tissues after pMnSOD treatment, while ACSL4 was downregulated. CONCLUSION: The present study provides evidence that the protective effects of MnSOD in irradiated HaCaT cells may be related to the inhibition of ferroptosis. The multi-site injections of pMnSOD had clear therapeutic and preventive effects on radiation-induced skin injury in rats. pMnSOD may have therapeutic value for the treatment of radiation-induced skin injury.


Assuntos
Ferroptose , Lesões por Radiação , Humanos , Ratos , Animais , Espécies Reativas de Oxigênio , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Pele/metabolismo , Plasmídeos/genética
13.
J Am Chem Soc ; 145(50): 27639-27649, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38054305

RESUMO

While chiral molecular rotors have unique frames and cavities to possibly generate switchable chiroptical functions, it still remains a formidable challenge to precisely restrict their rotations to activate certain functions such as fluorescence as well as circularly polarized luminescence (CPL), which are strongly related to the local molecular rotations. Herein, we design a pair of enantiopure helical cage rotors, which emit light neither at the molecular state nor in the crystal or aggregation states, although they contain luminophore groups. However, upon mounting with fluoroaromatic borane (TFPB) as a molecular brake, the phenyl rotation of the helical cage can be effectively hindered and fluorescence and CPL activities of the molecular cage are switched on. Crystal structure analysis reveals that the rotation is restricted through synergistic B-O-H-N bonding and a fluoroaromatic-aromatic (ArF-Ar) dipole interaction. Moreover, the helical cages are switched on stepwise with color-variable fluorescence and CPL by the inner brake in the molecular state and the outer brake in the supramolecular assemblies, respectively. This work not only provides the design idea of chiroptical molecular rotors but also unveils how fluorescence and CPL could be generated in cage rotor systems.

14.
Nat Commun ; 14(1): 8162, 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38071337

RESUMO

Topological phases of matter have attracted significant attention in recent years, due to the unusual robustness of their response to defects and disorder. Various research efforts have been exploring classical and quantum topological wave phenomena in engineered materials, in which different degrees of freedom (DoFs) - for the most part based on broken crystal symmetries associated with pseudo-spins - induce synthetic gauge fields that support topological phases and unveil distinct forms of wave propagation. However, spin is not the only viable option to induce topological effects. Intrinsic orbital DoFs in spinless systems may offer a powerful alternative platform, mostly unexplored to date. Here we reveal orbital-selective wave-matter interactions in acoustic systems supporting multiple orbital DoFs, and report the experimental demonstration of disorder-immune orbital-induced topological edge states in a zigzag acoustic 1D spinless lattice. This work expands the study of topological phases based on orbitals, paving the way to explore other orbital-dependent phenomena in spinless systems.

15.
Ann Clin Lab Sci ; 53(5): 719-725, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37945010

RESUMO

OBJECTIVE: To investigate the expression of lncRNA UCA1 in serum of patients with acute cerebral infarction (ACI) and its relationship with prognosis. METHODS: The serum lncRNA UCA1 level in participants was detected, and the correlation between the neurological function score (NIHSS score) of ACI patients and lncRNA UCA1 expression was analyzed. Patients were followed up at 3 months after discharge and were divided into favorable and unfavorable prognostic groups according to the modified Rankin scale (mRs). The risk factors of ACI patients with poor prognosis were analyzed, and the predictive value of each index for ACI prognosis was evaluated by ROC curve. RESULTS: The level of lncRNA UCA1 in ACI group was increased (P<0.001). ROC analysis showed that high lncRNA UCA1 expression had clinical significance for the diagnosis of ACI. Spearman correlation analysis revealed that NIHSS score was positively correlated with lncRNA UCA1 expression level in ACI group (r=0.6537, P<0.001). Hcy level and NIHSS score in poor prognosis group (n=63) were higher than those in good prognosis group (n=84), and lncRNA UCA1 level in serum in poor prognosis group was increased in comparison to good prognosis group (P<0.05). Logistic regression analysis investigated that admission NIHSS score, infarct size, and increased lncRNA UCA1 were the risk factors affecting the prognosis of ACI. CONCLUSION: Serum lncRNA UCA1 is abnormally elevated in ACI patients, and the elevated lncRNA UCA1 not only shows high accuracy in the diagnosis of ACI, but also has a certain predictive value for poor prognosis of ACI.


Assuntos
Isquemia Encefálica , RNA Longo não Codificante , Acidente Vascular Cerebral , Humanos , Infarto Cerebral/genética , Infarto Cerebral/diagnóstico , Relevância Clínica , Prognóstico , RNA Longo não Codificante/genética
16.
Nat Commun ; 14(1): 5319, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37658073

RESUMO

Cellulose, as a component of green plants, becomes attractive for fabricating biocompatible flexible functional devices but is plagued by hydrophilic properties, which make it easily break down in water by poor mechanical stability. Here we report a class of SiO2-nanoparticle-decorated bacteria-cellulose meta-skin with superior stability in water, excellent machining property, ultrathin thickness, and active bacteria-repairing capacity. We further develop functional ultrasonic metasurfaces based on meta-skin paper-cutting that can generate intricate patterns of ~10 µm precision. Benefited from the perfect ultrasound insulation of surface Cassie-Baxter states, we utilize meta-skin paper-cutting to design and fabricate ultrathin (~20 µm) and super-light (<20 mg) chip-scale devices, such as nonlocal holographic meta-lens and the 3D imaging meta-lens, realizing complicated acoustic holograms and high-resolution 3D ultrasound imaging in far fields. The decorated bacteria-cellulose ultrasonic metasurface opens the way for exploiting flexible and biologically degradable metamaterial devices with functionality customization and key applications in advanced biomedical engineering technologies.

17.
FEMS Microbiol Ecol ; 99(11)2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37771081

RESUMO

Litter decomposition is a fundamental ecosystem process controlling the biogeochemical cycling of energy and nutrients. Using a 360-day lab incubation experiment to control for environmental factors, we tested how litter quality (low C/N deciduous vs. high C/N coniferous litter) governed the assembly and taxonomic composition of bacterial communities and rates of litter decomposition. Overall, litter mass loss was significantly faster in soils amended with deciduous (DL) rather than coniferous (CL) litter. Communities degrading DL were also more taxonomically diverse and exhibited stochastic assembly throughout the experiment. By contrast, alpha-diversity rapidly declined in communities exposed to CL. Strong environmental selection and competitive biological interactions induced by molecularly complex, nutrient poor CL were reflected in a transition from stochastic to deterministic assembly after 180 days. Constraining how the diversity and assembly of microbial populations modulates core ecosystem processes, such as litter decomposition, will become increasingly important under novel climate conditions, and as policymakers and land managers emphasize soil carbon sequestration as a key natural climate solution.


Assuntos
Ecossistema , Plantas , Clima , Solo/química , Bactérias/genética , Folhas de Planta/química , Microbiologia do Solo
18.
Front Cardiovasc Med ; 10: 1145695, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324633

RESUMO

Aims: Few studies on early recurrence (ER) focused on patients with persistent atrial fibrillation (AF). We aimed to investigate the characteristics and clinical significance of ER in patients with persistent AF after catheter ablation (CA). Methods: A total of 348 consecutive patients who underwent first-time CA for persistent and long-standing persistent AF between January 2019 and May 2022 were investigated. Results: About 5/348 (1.44%) patients who failed to convert to sinus rhythm after CA were excluded. A total of 110/343 (32.1%) patients had ER, in which 98 (89.1%) were persistent and 50.9% occurred in the first 24 h after CA. Compared with the patients without ER, those with ER were more likely to have late recurrence (LR) (92.7% vs. 1.7%, P < 0.001) during a median follow-up of 13 (IQR 6-23) months. ER was the most significant independent predictor for LR (OR 120.5, 95% CI 41.5-349.8, P < 0.001). ER as atrial flutter (AFL) had a lower risk of LR when compared with ER as AF (P = 0.011) and both AF and AFL (P = 0.003). Early intervention of the patient with ER improved the short-term outcomes (P < 0.001), not long-term outcomes. Only 22/251 (8.76%) patients of LR appears among those who had no recurrence in the first month. Conclusions: Patients with persistent AF may not have a blanking period but rather have a risk period. Clinical significance of the blanking period should be given differential treatment between paroxysmal AF and persistent AF.

19.
J Phys Condens Matter ; 35(40)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37364581

RESUMO

The square-root operation can generate novel topological phases, whose nontrivial topological properties are inherited from the parent Hamiltonian. Here we report the acoustic realization of third-order square-root topological insulators by adding additional resonators between the site resonators of original diamond lattice. Due to the square-root operation, multiple acoustic localized modes appear in doubled bulk gaps. The bulk polarizations of the tight-binding models are employed to reveal the topological feature of the higher-order topological states. By tuning the coupling strength, we find the emergence of third-order topological corner states in doubled bulk gaps on tetrahedron-like and rhombohedron-like sonic crystals, respectively. The shape dependence of square-root corner states provides an extra degree of freedom for flexible manipulation on the sound localization. Furthermore, the robustness of the corner states in three-dimensional (3D) square-root topological insulator is well elucidated by introducing random disorders into the irrelevant bulk region of the proposed 3D lattices. This work extends square-root higher-order topological states into 3D system, and may find possible applications in selective acoustic sensors.

20.
BMC Surg ; 23(1): 146, 2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37248522

RESUMO

BACKGROUND: Postoperative pancreatic fistula (POPF) is the most serious complication and the main reason for morbidity and mortality after pancreaticoduodenectomy (PD). Currently, there exists no flawless pancreaticojejunal anastomosis approach. We presents a new approach called Chen's penetrating-suture technique for pancreaticojejunostomy (PPJ), which involves end-to-side pancreaticojejunostomy by suture penetrating the full-thickness of the pancreas and jejunum, and evaluates its safety and efficacy. METHODS: To assess this new approach, between May 2006 and July 2018, 193 consecutive patients who accepted the new Chen's Penetrating-Suture technique after a PD were enrolled in this study. Postoperative morbidity and mortality were evaluated. RESULTS: All cases recovered well after PD. The median operative time was 256 (range 208-352) min, with a median time of 12 (range 8-25) min for performing pancreaticojejunostomy. Postoperative morbidity was 19.7% (38/193) and mortality was zero. The POPF rate was 4.7% (9/193) for Grade A, 1.0% (2/193) for Grade B, and no Grade C cases and one urinary tract infection. CONCLUSION: PPJ is a simple, safe, and reliable technique with ideal postoperative clinical results.


Assuntos
Pancreaticoduodenectomia , Pancreaticojejunostomia , Humanos , Pancreaticojejunostomia/métodos , Pancreaticoduodenectomia/métodos , Anastomose Cirúrgica/métodos , Pâncreas/cirurgia , Fístula Pancreática/epidemiologia , Fístula Pancreática/etiologia , Fístula Pancreática/prevenção & controle , Complicações Pós-Operatórias/etiologia , Técnicas de Sutura/efeitos adversos
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