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1.
Adv Mater ; : e2404983, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-39011787

RESUMO

Modification of three-dimensional (3D) carbon hosts with metal oxides has been considered as advantageous for the formation of Li2O-rich solid electrolyte interface (SEI), which can show fast Li+ diffusion, and meanwhile alleviate dendrite problems caused by fragility and nonuniformity of native SEIs. However, the lack of convincing experimental evidence has made it difficult to unveil the true origin of oxygen in Li2O-rich SEIs until now. Herein, CoOx embedded carbon nanofibers (CNF-CoOx) are successfully prepared as high-performance Li anode hosts. By employing 18O isotope labeling, the role of CoOx during SEI evolution is elucidated, revealing that CoOx contributes significantly to Li2O formation by delivering oxygen. Benefiting from the rich Li2O content, the as-formed SEIs greatly improve the Li+ migration kinetics, and therefore, the CNF-CoOx@Li anode can exhibit excellent cycling stability in half, symmetrical, and full cells.

2.
Int J Med Robot ; 20(4): e2656, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38970289

RESUMO

BACKGROUND: Minimally invasive percutaneous plate osteosynthesis for humeral shaft fractures (HSFs) has limitations due to malreduction and radiation exposure. To address these limitations, we integrated robotics and 3D printing by incorporating plates as reduction templates. METHOD: The innovative technology facilitated closed reduction of HSFs in the operating theatre using 18 models with cortical marking holes. The dataset of the precontoured plate was imported into 3D planning software for virtual fixation and screw path planning. The models were divided into half to simulate transverse fractures. During the operation, the software generated drilling trajectories for robot navigation, and precise plate installation achieved automatic fracture reduction. RESULTS: The evaluation results of reduction accuracy revealed variations in length, apposition, alignment, and rotation that meet the criteria for anatomic reduction. High interoperator reliabilities were observed for all parameters. CONCLUSIONS: The proposed technology achieved anatomic reduction in simulated bones.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas , Fraturas do Úmero , Procedimentos Cirúrgicos Minimamente Invasivos , Impressão Tridimensional , Procedimentos Cirúrgicos Robóticos , Humanos , Fraturas do Úmero/cirurgia , Procedimentos Cirúrgicos Robóticos/métodos , Procedimentos Cirúrgicos Robóticos/instrumentação , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Úmero/cirurgia , Cirurgia Assistida por Computador/métodos , Estudo de Prova de Conceito , Software , Redução Fechada/métodos , Parafusos Ósseos
3.
Magn Reson Med ; 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38852173

RESUMO

PURPOSE: Velocity selective arterial spin labeling (VSASL) quantification assumes that the labeled bolus continuously moves into the imaging voxel during the post-labeling delay (PLD). Faster blood flow could lead to a bolus duration shorter than the applied PLD of VSASL and cause underestimation of cerebral blood flow (CBF). This study aims to evaluate the performance of velocity-selective inversion (VSI) prepared arterial spin labeling (ASL) with different PLDs and pseudo-continuous ASL (PCASL) for quantification of hypercapnia-induced cerebrovascular reactivity (CVR), using phase-contrast (PC) MRI as a global reference. METHODS: We compared CVR obtained by VSI-ASL with PLD of 1520 ms (VSASL-1520), 1000 ms (VSASL-1000), and 500 ms (VSASL-500), PCASL with PLD of 1800 ms (PCASL-1800), and PC MRI on eight healthy volunteers at two sessions. RESULTS: Compared with PC MRI, VSASL-1520 produced significantly lower global CVR values, while PCASL-1800, VSASL-1000, and VSASL-500 yielded more consistent results. The reduced CVR in VSASL-1520 was more pronounced in carotid territories including frontal and temporal lobes than in vertebral territories such as the occipital lobe. This is largely caused by the underestimated perfusion during hypercapnia due to the reduced bolus duration being less than the PLD. CONCLUSION: Although VSASL offers certain advantages over spatially selective ASL due to its reduced susceptibility to delayed ATT, this technique is prone to biases when the ATT is excessively short. Therefore, a short PLD should be employed for reliable perfusion and CVR quantification in populations or conditions with fast flow.

4.
Angew Chem Int Ed Engl ; : e202408026, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867467

RESUMO

The inevitable shuttling and slow redox kinetics of lithium polysulfides (LiPSs) as well as the uncontrolled growth of Li dendrites have strongly limited the practical applications of lithium-sulfur batteries (LSBs). To address these issues, we have innovatively constructed the carbon nanotubes (CNTs) encapsulated Co nanoparticles in situ grown on TiN-MXene nanosheets, denoted as TiN-MXene-Co@CNTs, which could serve simultaneously as both sulfur/Li host to kill "three birds with one stone" to (1) efficiently capture soluble LiPSs and expedite their redox conversion, (2) accelerate nucleation/decomposition of solid Li2S, and (3) induce homogeneous Li deposition. Benefiting from the synergistic effects, the TiN-MXene-Co@CNTs/S cathode with a sulfur loading of 2.5 mg cm-2 could show a high reversible specific capacity of 1129.1 mAh g-1 after 100 cycles at 0.1 C, and ultralong cycle life over 1000 cycles at 1.0 C. More importantly, it even achieves a high areal capacity of 6.3 mAh cm-2 after 50 cycles under a sulfur loading as high as 8.9 mg cm-2 and a low E/S ratio of 5.0 µL mg-1. Besides, TiN-MXene-Co@CNTs as Li host could deliver a stable Li plating/striping behavior over 1000 h.

5.
Injury ; 55(8): 111692, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38945080

RESUMO

INTRODUCTION: Humeral shaft fractures are a common injury of the upper limb, with the primary surgical treatment modality being the locking compression plate (LCP) technique. The advent of Anterior medial minimally invasive plate osteosynthesis (MIPO) technology has led to its gradual implementation in clinical practice. However, the efficacy and long-term outcomes of MIPO require further investigation. The objective of this study is to compare the therapeutic effects of LCP and MIPO in the management of humeral shaft fractures. METHODS: The present study conducted a retrospective review of patients diagnosed with humeral shaft fractures between June 2016 and December 2019. The patients were divided into MIPO and LCP groups based on the different surgical methods. The study analyzed the length of hospital stay, radiation exposure, operative time, and postoperative Disabilities of the Arm, Shoulder and Hand (DASH) scores using statistical methods. RESULTS: A total of 53 patients who met the inclusion criteria were included in the study. The MIPO group demonstrated a statistically significant reduction in length of hospital stay compared to the LCP group (length of hospital stay: 5.39 ± 2.23 days vs 12.00 ± 7.19 days, P < 0.001). All patients achieved callus formation after surgery. However, the MIPO group had significantly more radiation exposures than the LCP group (45.96 ± 19.49 vs 5.33 ± 2.20, P < 0.001). Additionally, there was no statistically significant difference observed in the time from admission to surgery, operative time,and healing time between the two groups (the time from admission to surgery: P = 0.593; operative time: P = 0.407; Healing time: P = 0.664). During the postoperative follow-up, the MIPO group exhibited significantly lower 6-week and 3-month DASH scores compared to the LCP group (6-week: 34.17 ± 12.16 vs 45.65 ± 22.94, P = 0.028; 3-month: 17.43 ± 11.70 vs 30.12 ± 9.80, P < 0.001). However, there was no statistically significant difference in the 6-month and 12-month DASH scores between the two groups (6-month: P = 0.787; 12-month: P = 0.058). CONCLUSION: The MIPO technique provides better short-term functional recovery of the shoulder and elbow compared to the LCP technique in the treatment of humeral shaft fractures, while ensuring equivalent surgical healing.

6.
Poult Sci ; 103(7): 103794, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38718539

RESUMO

Avian feather color is a fascinating trait, and the genetic mechanism of duck plumage formation is still in the preliminary stage. In this study, feather color of Liancheng White ducks was analyzed by determination of melanin content and RNA-seq analysis. In this research, 9 ducks from Mallards (n = 3), Liancheng White (n = 3) and Pekin ducks (n = 3) were used by high performance liquid chromatography (HPLC) and Masson-Fontana staining to reveal the difference of feather melanin content. RNA-seq from 11 hair follicle tissues (1- and 8-wk-old) of Liancheng White ducks (n = 5) and Pekin ducks (n = 7) was used to analyze the candidate genes for the feather melanin synthesis, and Immunofluorescence experiment was used to show the protein expression in 6 black- and white-feathered ducks. Pectorale, skin, liver, fat, brain, heart, kidney, lung, spleen of an 8-wk-old black-feathered Mallard were collected for candidate gene expression. The results showed that the contents of feathers, beak, web melanin in Liancheng White ducks were higher than in Pekin ducks (p < 0.05). Melanin within hair follicles was located in the barb ridge and hair matrix of black feather duck, also we found that TYRP1, TYR, SOX10 genes were differentially expressed between Liancheng White and Pekin ducks (p < 0.05), and these genes were mainly expressed showed in duck skin tissues. This study revealed the unique feather color phenotype of Liancheng White duck shedding light on the transcriptome that underlies it.


Assuntos
Patos , Plumas , Perfilação da Expressão Gênica , Folículo Piloso , Pigmentação , Animais , Plumas/química , Patos/genética , Pigmentação/genética , Folículo Piloso/metabolismo , Perfilação da Expressão Gênica/veterinária , Transcriptoma , Melaninas/metabolismo
7.
Heliyon ; 10(10): e30679, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38765037

RESUMO

This study explores the causes of coal bursts in the Xinzhou Kiln Mine, identifying key factors such as residual pillars, hard coal seams and/or roofs, stress concentration due to complex geological structures, and the stress distribution characteristics of the primary rock. A significant finding is that hydraulic cutting not only diminishes and redistributes the stress concentration region inside the coal seam but also mitigates the burst potential of the coal-rock mass, fundamentally reducing the likelihood of coal bursts. By taking Face No. 8937 in Xinzhou Kiln Mine as the test object, a coal burst prevention test was performed using hydraulic cutting. In combination with theoretical analysis and numerical simulation, the mechanism of hydraulic cutting for preventing coal burst was discussed, and reasonable cutting parameters were established. Onsite monitoring revealed that hydraulic cutting disrupts the integrity of the coal-rock mass, releases internal stress, and increases its water content, thereby weakening its burst tendency. Additionally, the deformation and fracturing of the cutting slots and the closure of boreholes shifted the stress concentration from the coal seam to deeper areas and to the two ribs. Post-cutting observations showed a significant reduction in both the frequency and impact energy of coal bursts; there was also a noticeable increase in the convergence of the roadway in the cutting area compared to non-cutting areas. Furthermore, displacement of the roof and floor increased by 78.9 % and that of the two ribs increased by 47.4 % after cutting, preventing the coal-rock mass from accumulating high stress. In conclusion, hydraulic cutting is a promising method for effectively preventing coal bursts and enhancing the safety of mining operations.

8.
Water Res ; 255: 121552, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38564899

RESUMO

Polyculture practices are important for achieving sustainable aquaculture development. Recently, hard clams polyculture in intensive shrimp ponds has been encouraged because bivalves can consume excess nutrients in aquaculture systems and sequester carbon. To evaluate the bioremediation potential of hard clams polyculture in intensive shrimp ponds, this study built an assessment model based on individual growth models and estimated the potential for nitrogen and phosphorus removal as well as CO2 fixation by hard clams. Firstly, key parameters required for model construction were obtained through field surveys and physiological experiments. Subsequently, an individual growth model for the hard clam Mercenaria mercenaria was developed based on the Dynamic Energy Budget (DEB) theory. Fitting of the growth data indicated that the model accurately replicated the growth patterns of hard clams, with relative root mean square errors of 9.87 % for shell length and 5.02 % for dry tissue weight. Finally, the assessment model for the bioremediation potential of hard clams demonstrated that, over 110 days in the intensive shrimp mariculture pond, the net removal of nitrogen and phosphorus by hard clams were 3.68 kg ha-1 and 0.81 kg ha-1, respectively, and CO2 fixation was 507.00 kg ha-1. These findings suggested that the DEB model is an effective tool for evaluating bivalve ecological remediation potential and can aid in selecting species for sustainable polyculture.

9.
Nat Commun ; 15(1): 3401, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649350

RESUMO

N-Glycosylated heterocycles play important roles in biological systems and drug development. The synthesis of these compounds heavily relies on ionic N-glycosylation, which is usually constrained by factors such as labile glycosyl donors, precious metal catalysts, and stringent conditions. Herein, we report a dehydroxylative radical method for synthesizing N-glycosides by leveraging copper metallaphotoredox catalysis, in which stable and readily available 1-hydroxy carbohydrates are activated for direct N-glycosylation. Our method employs inexpensive photo- and copper- catalysts and can tolerate some extent of water. The reaction exhibits a broad substrate scope, encompassing 76 examples, and demonstrates high stereoselectivity, favoring 1,2-trans selectivity for furanoses and α-selectivity for pyranoses. It also exhibits high site-selectivity for substrates containing multiple N-atoms. The synthetic utility is showcased through the late-stage functionalization of bioactive compounds and pharmaceuticals like Olaparib, Axitinib, and Metaxalone. Mechanistic studies prove the presence of glycosyl radicals and the importance of copper metallaphotoredox catalysis.

10.
J Hazard Mater ; 471: 134341, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38642496

RESUMO

Developing high-efficiency membrane for oil and dye removal is very urgent, because wastewater containing them can cause great damage to human and environment. In this study, a coated membrane was fabricated by applying DAC and PEI onto the commercial PVDF microfiltration membrane for supplying the demand. The coated membrane presents superhydrophlic and superoleophobic properties with a water contact angle of 0o and underwater oil contact angle exceed 150°, as well as excellent low underwater oil adhesion performance. The coated membrane shows high separation efficiency exceeded 99.0% and flux 350.0 L·m-2·h-1 when used for separating for six kinds of oil including pump oil, sunflower oil, n-hexadecane, soybean oil, diesel and kerosene in water emulsions. Additionally, the coated membrane can effectively remove anionic dyes, achieving rejection rates of 94.7%, 93.4%, 92.3%, 90.7% for the CR, MB, RB5, AR66, respectively. More importantly, the membrane was able to simultaneously remove emulsified oil and soluble anionic dyes in wastewater containing both of them. Therefore, this novel coated membrane can be a promising candidate for treating complex wastewater.

12.
Magn Reson Med ; 92(2): 761-771, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38523590

RESUMO

PURPOSE: This study evaluated the velocity-selective (VS) MRA with different VS labeling modules, including double refocused hyperbolic tangent, eight-segment B1-insensitive rotation, delay alternating with nutation for tailored excitation, Fourier transform-based VS saturation, and Fourier transform-based inversion. METHODS: These five VS labeling modules were evaluated first through Bloch simulations, and then using VSMRA directly on various cerebral arteries of healthy subjects. The relative signal ratios from arterial ROIs and surrounding tissues as well as relative arteria-tissue contrast ratios of different methods were compared. RESULTS: Double refocused hyperbolic tangent and eight-segment B1-insensitive rotation showed very similar labeling effects. Delay alternating with nutation for tailored excitation yielded high arterial signal but with residual tissue signal due to the spatial banding effect. Fourier transform-based VS saturation with half the time of other techniques serves as an efficient nonsubtractive VSMRA method, but the remaining tissue signal still obscured some small distal arteries that were delineated by other subtraction-based VSMRA, allowing more complete cancelation of static tissue. Fourier transform-based inversion produced the highest arterial signal in VSMRA with minimal tissue background. CONCLUSION: This is the first study that angiographically compared five different VS labeling modules. Their labeling characteristics on arteries and tissue and implications for VSMRA and VS arterial spin labeling are discussed.


Assuntos
Artérias Cerebrais , Análise de Fourier , Angiografia por Ressonância Magnética , Humanos , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/fisiologia , Angiografia por Ressonância Magnética/métodos , Adulto , Masculino , Feminino , Algoritmos , Velocidade do Fluxo Sanguíneo/fisiologia , Marcadores de Spin , Angiografia Cerebral/métodos , Circulação Cerebrovascular/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Interpretação de Imagem Assistida por Computador/métodos
13.
Angew Chem Int Ed Engl ; 63(16): e202401272, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38375744

RESUMO

Widely acknowledged that the capacity of Li-O2 batteries (LOBs) should be strongly determined by growth behaviors of the discharge product of lithium peroxide (Li2O2) that follows both coexisting surface and solution pathways. However until now, it remains still challenging to achieve dynamic modulation on Li2O2 morphologies. Herein, the photo-responsive Au nanoparticles (NPs) supported on reduced oxide graphene (Au/rGO) have been utilized as cathode to manipulate oxygen reduction reaction (ORR) kinetics by aid of surface plasmon resonance (SPR) effects. Thus, we can experimentally reveal the importance of matching ORR kinetics with Li+ migration towards battery performance. Moreover, it is found that Li+ concentration polarization caused "sudden death" of LOBs is supposed to be just a form of suspended animation that could timely recover under irradiation. This work provides us an in-depth explanation on the working mechanism of LOBs from a kinetic perspective, offering valuable insights for the future battery design.

14.
Brain Sci ; 14(2)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38391701

RESUMO

MR perfusion imaging is important in the clinical evaluation of primary brain tumors, particularly in differentiating between true progression and treatment-induced change. The utility of velocity-selective ASL (VSASL) compared to the more commonly utilized DSC perfusion technique was assessed in routine clinical surveillance MR exams of 28 patients with high-grade gliomas at 1.5T. Using RANO criteria, patients were assigned to two groups, one with detectable residual/recurrent tumor ("RT", n = 9), and the other with no detectable residual/recurrent tumor ("NRT", n = 19). An ROI was drawn to encompass the largest dimension of the lesion with measures normalized against normal gray matter to yield rCBF and tSNR from VSASL, as well as rCBF and leakage-corrected relative CBV (lc-rCBV) from DSC. VSASL (rCBF and tSNR) and DSC (rCBF and lc-rCBV) metrics were significantly higher in the RT group than the NRT group allowing adequate discrimination (p < 0.05, Mann-Whitney test). Lin's concordance analyses showed moderate to excellent concordance between the two methods, with a stronger, moderate correlation between VSASL rCBF and DSC lc-rCBV (r = 0.57, p = 0.002; Pearson's correlation). These results suggest that VSASL is clinically feasible at 1.5T and has the potential to offer a noninvasive alternative to DSC perfusion in monitoring high-grade gliomas following therapy.

15.
Med Eng Phys ; 123: 104079, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38365332

RESUMO

Less invasive fixation techniques, such as intramedullary nailing (IMN) and minimally invasive percutaneous plate osteosynthesis (MIPPO), are now the preferred choices for treating tibia shaft fractures (TSFs). However, malreduction and radiation exposure are the main deficiencies associated with less invasive fixation techniques, especially when assessing rotation around the shaft axis intra-operatively. The purpose of this study was to investigate the feasibility and reduction accuracy of an innovative technology that integrates robotics and 3D printing for achieving anatomical reduction of TSFs with MIPPO. The surgical workflow from a standardized CT protocol, via 3D reconstruction, 3D printing tibia model, pre-contouring plate, 3D scanning plate, 3D planning of the trajectories of the robot, and use of a commercial surgical robot, robot-assisted screw hole drilling, to automatic fracture reduction through precise installation of the plate was described. The reduction accuracy was evaluated by an optical tracking system. The mean variations of 1.95 ± 1.36mm in length, 1.63 ± 0.92 mm in apposition, 2.78 ± 1.69° in alignment, and 1.99 ± 1.81° in rotation. The interoperator reliabilities were almost perfect, with values of 0.91, 0.93, 0.92, and 0.90, respectively. The proposed technology achieved anatomic reduction on phantom bones.


Assuntos
Fixação Intramedular de Fraturas , Robótica , Fraturas da Tíbia , Humanos , Tíbia , Fixação Interna de Fraturas/métodos , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/cirurgia , Impressão Tridimensional , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Placas Ósseas , Resultado do Tratamento
16.
Chemistry ; 30(17): e202304113, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38182543

RESUMO

Platinum supramolecular complexes based on photosensitizers have garnered great interest in photodynamic therapy (PDT) due to Pt (II) centers as chemotherapeutic agents to eliminate tumor cells completely, which greatly improve the antitumor efficacy of PDT. However, in comparison to precursor photosensitizer ligand, the formed platinum supramolecular complexes typically exhibit inferior outcomes in terms of reactive oxygen species (ROS) generation. How to boost ROS generation in the formed platinum supramolecular complexes for enhanced PDT is an enticing yet highly challenging task. Here we report a Pt-coordination-based dimeric photosensitizer complex (Cz-BTZ-Py)2Pt(OTf)2. It is found that comparing with photosensitizer ligand Cz-BTZ-Py, the formed supramolecular complex exhibit redshifts of absorption wavelength as well as enhanced ROS generation efficiency. Moreover, type-I ROS generation (O2⋅-) is produced in the formed platinum supramolecular complexes mainly due to a reduced energy gap ΔEST resulting from exciton coupling between two photosensitizer ligands. And type-I ROS (O2⋅-) generation significantly amplifies the photodynamic therapy (PDT) outcomes. In vitro evaluation shows excellent photochemotherapy performance of (Cz-BTZ-Py)2Pt(OTf)2 nanoparticles. We anticipate this work would provide a novel approach to design type-I photosensitizers for efficient PDT.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio , Platina , Ligantes , Fotoquimioterapia/métodos , Oxigênio
17.
Adv Mater ; 36(1): e2305370, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37506027

RESUMO

For most organic synaptic transistors based on the charge trapping effect, different atmosphere conditions lead to significantly different device performance. Some devices even lose the synaptic responses under vacuum or inert atmosphere. The stable device performance of these organic synaptic transistors under varied working environments with different humidity and oxygen levels can be a challenge. Herein, a moisture- and oxygen-insensitive organic synaptic device based on the organic semiconductor and photoinitiator molecules is reported. Unlike the widely reported charge trapping effect, the photoinduced free radical is utilized to realize the photosynaptic performance. The resulting synaptic transistor displays typical excitatory postsynaptic current, paired-pulse facilitation, learning, and forgetting behaviors. Furthermore, the device exhibits decent and stable photosynaptic performances under high humidity and vacuum conditions. This type of organic synaptic device also demonstrates high potential in ultraviolet B perception based on its environmental stability and broad ultraviolet detection capability. Finally, the contrast-enhanced capability of the device is successfully validated by the single-layer-perceptron/double-layer network based Modified National Institute of Standards and Technology pattern recognition. This work could have important implications for the development of next-generation environment-stable organic synaptic devices and systems.

18.
Acta Biomater ; 174: 400-411, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38036283

RESUMO

Photothermal agents (PTAs) based on donor (D)-acceptor (A) NIR fluorophores show great promise in photothermal therapy due to their accessible molecular engineering to mediate excitation energy for high photothermal conversion. Except for molecular structural modification of D-A fluorophores, intermolecular arrangement in space greatly influences their excitation energy dissipation as well. But how to mediate their intermolecular arrangement is still challenging. Here we control the intermolecular orientation of chromophores via metal coordination to form Pt-bridged dimeric D-A fluorophores with different geometries. The formed configuration isomers show different intermolecular exciton coupling behaviors involving charge transfer (CT) evolution and internally limited molecular rotation, which greatly affect excited-energy dissipation. Compared with folded configuration with intense NIR emission (quantum yields (QYs) = 15.62 %), linear configuration favors non-radiative decays with low QYs (6.99 %) but enhanced photothermal conversion efficiency (PCE = 41.57 %). The self-assembled nanoparticles combining Pt-bridged dimeric D-A fluorophores with DSPE-PEG2000-RGD reveal superior photothermal therapeutic features with desirable biosafety. This research provides a new designing concept to mediate excited-state energy dissipation pathways at a sub-nano level for enhanced photothermal conversion. STATEMENT OF SIGNIFICANCE: D-A fluorophores as photothermal agents attract great attention in photothermal therapy due to their accessible molecular engineering. Besides molecular engineering of D-A fluorophores, the intermolecular packing manner is proven to greatly affect their excitation energy dissipation. But how to control intermolecular arrangement is still challenging. Here we control the intermolecular orientation of chromophores via metal coordination to form Pt-bridged dimeric D-A fluorophores with different geometries. Compared to the folded configuration, linear configuration facilitates charge transfer (CT) evolution and molecular rotation, which promotes non-radiative decays of excited energy for enhanced photothermal therapy.


Assuntos
Terapia Fototérmica , Polímeros , Bandagens , Corantes Fluorescentes , Metais
19.
Mater Horiz ; 11(4): 958-968, 2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38099601

RESUMO

Pain perception nociceptors (PPN), an important type of sensory neuron, are capable of sending out alarm signals when the human body is exposed to destructive stimuli. Simulating the human ability to perceive the external environment and spontaneously avoid injury is a critical function of neural sensing of artificial intelligence devices. The demand for developing artificial PPN has subsequently increased. However, due to the application scenarios of bionic electronic devices such as human skin, electronic prostheses, and robot bodies, where a certain degree of surface deformation constantly occurs, the ideal artificial PPN should have the stretchability to adapt to real scenarios. Here, an organic semiconductor nanofiber artificial pain perception nociceptor (NAPPN) based on a pre-stretching strategy is demonstrated to achieve key pain aspects such as threshold, sensitization, and desensitization. Remarkably, while stretching up to 50%, the synaptic behaviors and injury warning ability of NAPPN can be retained. To verify the wearability of the device, NAPPN was attached to a curved human finger joint, on which PPN behaviors were successfully mimicked. This provides a promising strategy for realizing neural sensing function on either deformed or mobile electronic devices.


Assuntos
Inteligência Artificial , Nociceptores , Humanos , Células Receptoras Sensoriais , Eletrônica , Percepção da Dor
20.
Artigo em Inglês | MEDLINE | ID: mdl-37885270

RESUMO

Increasing attention has been paid to organic electronics emulating the characteristics and functions of the peripheral nervous system (PNS) and central nervous system (CNS) in living organisms, which has important implications for exploring electronics from the underlying architecture to emulate biological sensory synapses/neurons and develop brain-like chips. However, the vast majority of current research has been limited to biomimetic electronics that implement the functionality of a single PNS or CNS. Here, we develop solution-processed optoelectronic synaptic transistors (OSTs) that simultaneously simulate the visual nociceptor perception functions of the PNS as well as the memorizing and computing functions of the CNS, where CsPbCl3 quantum dots (QDs) and organic semiconductor serve as the photoactive layer and channel layer, respectively. Benefiting from the distinctive absorption characteristic of CsPbCl3 QDs, the OSTs illustrate decent ultraviolet light selectivity, which can be utilized to mimic visual nociceptor behavior triggered by ultraviolet irradiation for pain perception. Furthermore, the OSTs successfully achieve 1000 conductance states, which also confirms the outstanding conductivity regulation ability of the OSTs and their potential in pattern recognition based on artificial neural networks. This work provides a pathway for the development of future artificial vision and neuromorphic computing using OSTs based on solution-processable organic semiconductors and QDs.

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