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1.
J Environ Manage ; 370: 122513, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39303601

RESUMO

To convert Na2SO4 into other high-value products (NaOH, H2SO4, and (NH4)2SO4), three types of cell configurations of electrodialysis (ED) were applied (three-compartment bipolar membrane ED (BMED), four-compartment ED metathesis (EDM) and five-compartment bipolar membrane ED multifunction (BMEDM)) and parameters such as average voltage variation, removal ratio of salt, product concentration, conversion rate, ion flux, and energy consumption were calculated and compared. The experimental results and calculations indicated that the overall performance of BMEDM was inferior to that of BMED and EDM. An industrial model was established, which indicated that the net profit from converting Na2SO4 using BMEDM was always higher than that from BMED and EDM. Based on the advantages of low investment (132 $) and energy cost (152 $/t Na2SO4), EDM was applicable to factories with a low output of Na2SO4 (production capacity <45%), whereas BMED (157.3 $/t Na2SO4) and BMED-5 (227.6 $/t Na2SO4) were applicable to factories with a high output of Na2SO4 (production capacity >45%) based on high net profits.

2.
Colloids Surf B Biointerfaces ; 245: 114246, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39299040

RESUMO

The use of dressings in clinical settings is common for the purpose of wound wrapping and creating an optimal microenvironment to enhance the healing process. Proper coverage of wounds with dressings serves as the fundamental basis for effective wound healing. Unfortunately, non-standard coverage by hands can cause pain and secondary damage to patients, while slow manual application during treatment of extensive burns may increase the risk of wound infection. Herein, drawing inspiration from the microstructure and hygroscopic deformation observed in pine cones, we propose a polyvinyl alcohol/polysulfone (PVA/PSF) smart dressing. This bioinspired smart dressing exhibits rapid bending deformation under high moisture condition, allowing easy adjustment of bending amplitude, speed, and direction. Moreover, the smart dressing is capable of rapid bending and autonomous wrapping around "artificial wounds" on a doll's body, as well as fitting irregularly shaped "hand wounds" and extensive "arm wounds" on human subjects. By integrating two layers into one dressing design, we endow it with dual functionality: The hygroscopic PVA layer facilitates transversal liquid transport to effectively reduce exudate accumulation in the wound bed while maintaining proper moisture levels; meanwhile, the highly hydrophobic PSF layer repels various aqueous solutions to protect against external contaminants. In vivo results confirm that this multifunctional smart dressing promotes collagen synthesis and accelerates angiogenesis for accelerated wound healing. We believe that this innovative multifunctional approach to wound management will provide valuable insights into wound healing therapy.

3.
Biosens Bioelectron ; 267: 116786, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39326320

RESUMO

Technologies that established in vivo evaluations of soft-tissue biomechanics and temperature are essential to biological research and clinical diagnostics, particularly for a wide range of eye-related diseases such as glaucoma. Of importance are advanced bioelectronic devices for high-precise monitoring of intraocular pressure (IOP) and various ocular temperatures, as clinically proven uses for glaucoma diagnosis. Existing characterization methods are temporary, single point, and lack microscale resolution, failing to measure continuous IOP fluctuation across the long-term period. Here, this work presents a multi-functional smart contact lens, capable of rapidly capturing IOP fluctuation and ocular surface temperature (OST) for assistance for clinical use. The microscale device design is programmable and determined by finite element analysis simulation, with detailed experiments of ex vivo porcine eyeballs. Such compact bioelectronics can provide high-precise measurement with sensitivity of 0.03% mmHg-1 and 1.2 Ω °C-1 in the range of Δ2∼50 mmHg and 30-50 °C, respectively. In vivo tests of bio-integration with a living rabbit can evaluate real-time IOP fluctuation and OST, as of biocompatibility assessments verified through cellular and animal experiments. The resultant bioelectronic devices for continuous precise characterization of living eyeballs can offer broad utility for hospital diagnosis of a wide range of eye-related disorders.

4.
Micromachines (Basel) ; 15(9)2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39337740

RESUMO

A novel photonic-assisted multifunctional radar system was proposed and experimentally investigated. This system can simultaneously achieve frequency-doubled linear frequency modulation (LFM) signal generation, de-chirp reception, self-interference cancellation, and frequency measurement in an integrated transmit-receive radar. First, a high-frequency and broadband LO signal was obtained with photonic frequency doubling, which improved the center frequency and bandwidth of the radar detection system. Then, photonic-assisted interference cancellation was used to reduce the impact of interference signals in radar de-chirp reception. Finally, the microwave frequency measurement was achieved by establishing a mapping relationship between the envelope response time of the intermediate frequency (IF) electrical filter and the microwave frequency to be tested. Both theoretical and experimental investigations were performed. The results showed that an LFM signal with a frequency range of 12-18 GHz was obtained with photonic frequency doubling. Photonic-assisted self-interference cancellation reduced the impact of interference signals in radar de-chirp reception by more than 12.1 dB for an LFM signal bandwidth of 6 GHz. In the frequency measurement module, the difference between the frequency to be tested, generated by the external signal source, and that calculated in the experiment is the measurement error, and a measurement resolution better than 14 MHz was achieved in the range of 12.14 GHz-18.14 GHz. The proposed system is suitable for miniaturized multifunctional radar signal processing systems with continuous operation of transmitting and receiving antennas in unmanned aerial vehicles (UAVs), automotive radar, relatively close spatial locations, and so on. In addition, it can simplify the system structure and reduce space occupation.

5.
Int J Biol Macromol ; 278(Pt 2): 134711, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39151847

RESUMO

Pressure ulcer dressings with different functions can enhance wound healing ability to varying degrees; however, pressure ulcer dressings that integrate various functions and break the resistance of bacteria to traditional antibiotics have not been widely studied. We proposed a self-pumping/super-absorbent/transportable drug dressing (PLD-SLD), polycaprolactone (PCL)/sodium alginate (SA) was used to load platelet-derived growth factor (PDGF) and lidocaine hydrochloride (LID) by Janus electrospinning and self-assembly technology, and Ɛ-polylysine was used as a biological bacteriostatic agent to prepare a multi-layer dressing. SEM showed that the dressing had a fluffy structure. The dressing can pump the exudate to the SA layer away from the skin. The swelling ratio reached 1378.667 ± 44.752 %. Coagulate blood in 5 min. On the 8th day, the unclosed area rate of the PLD-SLD dressing group was 16.112 ± 0.088 % lower than that of the model group. Importantly, the dressing can induce the expression of CD31, VEGF, α-SMA, and reduce the expression of CD68, thereby giving priority to wound healing. There was no scar formation after healing. In this study, a new dressing preparation method was proposed for the problems of exudate management, infection control, pain relief and healing promotion of stage 3-4 pressure ulcer healing.


Assuntos
Alginatos , Bandagens , Poliésteres , Úlcera por Pressão , Cicatrização , Alginatos/química , Úlcera por Pressão/tratamento farmacológico , Úlcera por Pressão/terapia , Poliésteres/química , Cicatrização/efeitos dos fármacos , Animais , Ratos , Masculino , Lidocaína/farmacologia , Lidocaína/química
6.
Int J Biol Macromol ; 278(Pt 4): 134830, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39154694

RESUMO

Diabetic infected bone defects (DIBD) with abnormal immune metabolism are prone to the hard-to-treat bacterial infections and delayed bone regeneration, which present significant challenges in clinic. Control of immune metabolism is believed to be important in regulating fundamental immunological processes. Here, we developed a macrophage metabolic reprogramming hydrogel composed of modified silk fibroin (Silk-6) and poly-l-lysine (ε-PL) and further integrated with M2 Macrophage-derived Exo (M2-Exo), named Silk-6/ε-PL@Exo. This degradable hydrogel showed a broad-spectrum antibacterial performance against both Gram-positive and -negative bacteria. More importantly, the release of M2-Exo from Silk-6/ε-PL@Exo could target M1 macrophages, modulating the activity of the key enzyme hexokinase II (HK2) to control the inflammation-related NF-κB pathway, alleviate lactate accumulation, and inhibit glycolysis to normalize the cycle, thereby promoting M1-to-M2 balance. Using a rat model of DIBD, Silk-6/ε-PL@Exo hydrogel promoted infection control, balanced immune responses and accelerated the bone defect healing. Overall, this study demonstrates that this Silk-6/ε-PL @Exo is a promising filler biomaterial with multi-function to treat DIBD and emphasizes the importance of metabolic reprogramming in bone regeneration.


Assuntos
Regeneração Óssea , Exossomos , Fibroínas , Hidrogéis , Macrófagos , Animais , Hidrogéis/química , Ratos , Regeneração Óssea/efeitos dos fármacos , Exossomos/metabolismo , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Fibroínas/química , Fibroínas/farmacologia , Camundongos , Seda/química , Diabetes Mellitus Experimental , Células RAW 264.7 , Masculino , Antibacterianos/farmacologia , Antibacterianos/química , Ratos Sprague-Dawley , NF-kappa B/metabolismo , Reprogramação Metabólica
7.
Biosens Bioelectron ; 265: 116710, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39190969

RESUMO

The advancement in miniaturized Raman spectrometers, coupled with the single-molecule-level sensitivity and unique fingerprint identification capability of surface-enhanced Raman scattering (SERS), offers great potential for point-of-care testing (POCT). Despite this, accurately quantifying analyte molecules, particularly in complex samples with limited sample volumes, remains difficult. Herein, we present a versatile and reusable SERS microplatform for highly sensitive and reliable quantitative detection of adenosine triphosphate (ATP) in biological fluids. The platform utilizes gold-Prussian blue core-shell nanoparticles modified with polyethyleneimine (Au@PB@PEI NPs), embedded within gold nanoparticle-immobilized capillary-based silica monolithic materials. PB acts as an internal standard, while PEI enhances molecular capture. The periodic, bimodal porous structure of the silica monolithic materials provides uniform and abundant sites for nanoparticle attachment, facilitating rapid liquid permeation, intense SERS enhancement, and efficient enrichment. The platform regulates ATP capture and release through magnesium ions in the liquid phase, eliminating matrix interferences and enabling platform reuse. Integrating efficient molecular enrichment, separation, an interference-free internal standard, a liquid flow channel, and a detection chamber, our platform offers simplicity in operation, exceptional sensitivity and accuracy, and rapid analysis (∼10 min). Employing PB as an internal calibration standard, ratiometric Raman signals (I732/I2123) facilitate precise ATP quantification, achieving a remarkable limit of detection down to 0.62 pM. Furthermore, this platform has been proven to be highly reproducible and validated for ATP quantification in both mouse cerebrospinal fluid and human serum, underscoring its immense potential for POCT applications.


Assuntos
Trifosfato de Adenosina , Técnicas Biossensoriais , Ouro , Nanopartículas Metálicas , Testes Imediatos , Análise Espectral Raman , Análise Espectral Raman/métodos , Trifosfato de Adenosina/análise , Trifosfato de Adenosina/sangue , Ouro/química , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Nanopartículas Metálicas/química , Animais , Humanos , Limite de Detecção , Camundongos , Polietilenoimina/química , Ferrocianetos/química , Desenho de Equipamento , Dióxido de Silício/química
8.
Int J Biol Macromol ; 277(Pt 4): 134636, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39128752

RESUMO

To mitigate environmental impacts in food preservation, the development of a multifunctional membrane for packaging is of importance. In this study, we have successfully fabricated a nanofibrous membrane using an eco-friendly electrospinning technique, comprising polyvinyl alcohol (PVA), chitosan (CS), and tannic acid (TA). The resulting nanofibrous membranes were crosslinked with glutaraldehyde (GA) and surface modified with ZnO. Our findings demonstrate that the crosslinking process enhances water resistance, reduces water vapor permeability, improves tensile strength (from 3 to 18 MPa), and enhances thermal stability (increasing decomposition temperature from 225 °C to 310 °C). Furthermore, the incorporation of TA and ZnO provides antioxidant properties to the membrane, effectively preventing food decomposition caused by UV-induced oxidation. Additionally, CS, TA, and ZnO synergistically exhibit a remarkable antibacterial effect with a bacteriostasis rate exceeding 99.9 %. The strawberry fresh-keeping experiment further confirms that our developed membrane significantly extends shelf life by up to 6 days. Moreover, cytotoxicity assays confirm the non-toxic nature of these membranes. The innovative significance of this study lies in proposing a robust GA-PVA/CS/TA@ZnO nanofibrous membrane with excellent mechanical properties, biocompatibility, and multiple functionalities including antibacterial, anti-ultraviolet, and anti-oxidation capabilities. It has tremendous potential for applications in active food packaging materials.


Assuntos
Quitosana , Embalagem de Alimentos , Conservação de Alimentos , Frutas , Membranas Artificiais , Álcool de Polivinil , Quitosana/química , Álcool de Polivinil/química , Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Frutas/química , Antioxidantes/química , Antioxidantes/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Taninos/química , Resistência à Tração , Nanofibras/química , Permeabilidade , Vapor , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Fragaria/química
9.
Sensors (Basel) ; 24(15)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39123870

RESUMO

This study proposes a dual-functional terahertz device based on the Dirac semimetal, serving as both a sensing element and a band-pass filter. The device's operating mode can switch between these two functions by utilizing the phase transition property of vanadium dioxide (VO2). When VO2 is in the insulating state, the device functions as a sensing element. The simulation results demonstrate an impressive refractive index sensitivity of 374.40 GHz/RIU (Refractive Index Unit). When VO2 is in the metallic state, the device functions as a band-pass filter, exhibiting a center frequency of 2.01 THz and a 3 dB fractional bandwidth of 0.91 THz. The integration of these dual functionalities within a single terahertz device enhances its utility in both sensing and filtering applications.

10.
J Neuroeng Rehabil ; 21(1): 148, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39217378

RESUMO

BACKGROUND: Eye tracking technology not only reveals the acquisition of visual information at fixation but also has the potential to unveil underlying cognitive processes involved in learning to use a multifunction prosthetic hand. It also reveals gaze behaviours observed during standardized tasks and self-chosen tasks. The aim of the study was to explore the use of eye tracking to track learning progress of multifunction hands at two different time points in prosthetic rehabilitation. METHODS: Three amputees received control training of a multifunction hand with new control strategy. Detailed description of control training was collected first. They wore Tobii Pro2 eye-tracking glasses and performed a set of standardized tasks (required to switch to different grips for each task) after one day of training and at one-year-follow-up (missing data for Subject 3 at the follow up due to socket problem). They also performed a self-chosen task (free to use any grip for any object) and were instructed to perform the task in a way how they would normally do at home. The gaze-overlaid videos were analysed using the Tobii Pro Lab and the following metrics were extracted: fixation duration, saccade amplitude, eye-hand latency, fixation count and time to first fixation. RESULTS: During control training, the subjects learned 3 to 4 grips. Some grips were easier, and others were more difficult because they forgot or were confused with the switching strategies. At the one-year-follow-up, a decrease in performance time, fixation duration, eye-hand latency, and fixation count was observed in Subject 1 and 2, indicating an improvement in the ability to control the multifunction hand and a reduction of cognitive load. An increase in saccade amplitude was observed in both subjects, suggesting a decrease in difficulty to control the prosthetic hand. During the standardized tasks, the first fixation of all three subjects were on the multifunction hand in all objects. During the self-chosen tasks, the first fixations were mostly on the objects first. CONCLUSION: The qualitative data from control training and the quantitative eye tracking data from clinical standardized tasks provided a rich exploration of cognitive processing in learning to control a multifunction hand. Many prosthesis users prefer multifunction hands and with this study we have demonstrated that a targeted prosthetic training protocol with reliable assessment methods will help to lay the foundation for measuring functional benefits of multifunction hands.


Assuntos
Membros Artificiais , Tecnologia de Rastreamento Ocular , Mãos , Aprendizagem , Humanos , Masculino , Mãos/fisiologia , Adulto , Amputados/reabilitação , Pessoa de Meia-Idade , Feminino , Fixação Ocular/fisiologia , Desempenho Psicomotor/fisiologia
11.
ACS Appl Mater Interfaces ; 16(36): 47832-47843, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39192455

RESUMO

The construction of heterogeneous microstructure and the selection of multicomponents have turned into a research hotspot in developing ultralight, multifunctional, high-efficiency electromagnetic wave absorbing (EMA) materials. Although aerogels are promising materials to fulfill the above requirements, the increase in functional fillers inevitably leads to the deterioration of intrinsic properties. Tuning the electromagnetic properties from the structural design point of view remains a difficult challenge. Herein, we design customized pore creation strategies via introducing sacrificial templates to optimize the conductive path and construct the discontinuous dielectric medium, increasing dielectric loss and achieving efficient microwave absorption properties. A 3D porous composite (MEM) was crafted, which encapsulated an EVA/FeCoNi (EVA/MNPs) framework with Ti3C2Tx MXene coating by employing a direct heated cross-linking and immersion method. Controllable adjustment of the conductive network inside the porous structure and regulation of the dielectric character are achieved by porosity variation. Eventually, the MEM-5 with a porosity of 66.67% realizes RLmin of -39.2 dB (2.2 mm) and can cover the entire X band. Moreover, through off-axis electronic holography and the calculation of conduction loss and polarization loss, the dielectric property is deeply investigated, and the inner mechanism of optimization is pointed out. Thanks to the inherent characteristic of EVA and the porous structure, MEM-5 showed excellent thermal insulating and superior compressibility, which can maintain 60 °C on a 90-100 °C continuous heating stage and reached a maximum compressive strength of 60.12 kPa at 50% strain. Conceivably, this work provides a facile method for the fabrication of highly efficient microwave absorbers applied under complex conditions.

12.
Adv Mater ; 36(36): e2403141, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39011796

RESUMO

Silicone-based devices have the potential to achieve an ideal interface with nervous tissue but suffer from scalability, primarily due to the mechanical mismatch between established electronic materials and soft elastomer substrates. This study presents a novel approach using conventional electrode materials through multifunctional nanomesh to achieve reliable elastic microelectrodes directly on polydimethylsiloxane (PDMS) silicone with an unprecedented cellular resolution. This engineered nanomesh features an in-plane nanoscale mesh pattern, physically embodied by a stack of three thin-film materials by design, namely Parylene-C for mechanical buffering, gold (Au) for electrical conduction, and Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) for improved electrochemical interfacing. Nanomesh elastic neuroelectronics are validated using single-unit recording from the small and curvilinear epidural surface of mouse dorsal root ganglia (DRG) with device self-conformed and superior recording quality compared to plastic control devices requiring manual pressing is demonstrated. Electrode scaling studies from in vivo epidural recording further revealed the need for cellular resolution for high-fidelity recording of single-unit activities and compound action potentials. In addition to creating a minimally invasive device to effectively interface with DRG sensory afferents at a single-cell resolution, this study establishes nanomeshing as a practical pathway to leverage traditional electrode materials for a new class of elastic neuroelectronics.


Assuntos
Gânglios Espinais , Ouro , Polímeros , Xilenos , Animais , Camundongos , Gânglios Espinais/citologia , Ouro/química , Polímeros/química , Xilenos/química , Microeletrodos , Poliestirenos/química , Dimetilpolisiloxanos/química , Elasticidade , Nanoestruturas/química , Potenciais de Ação/fisiologia , Compostos Bicíclicos Heterocíclicos com Pontes/química , Tiofenos/química
13.
ACS Nano ; 18(32): 20886-20933, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39080827

RESUMO

Gut microbiota plays a crucial role in maintaining host homeostasis, impacting the progression and therapeutic outcomes of diseases, including inflammatory bowel disease, cancer, hepatic conditions, obesity, cardiovascular pathologies, and neurologic disorders, via immune, neural, and metabolic mechanisms. Hence, the gut microbiota is a promising target for disease therapy. The safety and precision of traditional microbiota regulation methods remain a challenge, which limits their widespread clinical application. This limitation has catalyzed a shift toward the development of multifunctional delivery systems that are predicated on microbiota modulation. Guided by bioinspired strategies, an extensive variety of naturally occurring materials and mechanisms have been emulated and harnessed for the construction of platforms aimed at the monitoring and modulation of gut microbiota. This review outlines the strategies and advantages of utilizing bioinspired principles in the design of gut microbiota intervention systems based on traditional regulation methods. Representative studies on the development of bioinspired therapeutic platforms are summarized, which are based on gut microbiota modulation to confer multiple pharmacological benefits for the synergistic management of diseases. The prospective avenues and inherent challenges associated with the adoption of bioinspired strategies in the refinement of gut microbiota modulation platforms are proposed to augment the efficacy of disease treatment.


Assuntos
Microbioma Gastrointestinal , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Animais , Sistemas de Liberação de Medicamentos
14.
Adv Mater ; 36(35): e2405767, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39003607

RESUMO

Durable repellent surfaces of high transparency find key applications in daily life and industry. Nevertheless, developing anti-reflective coatings with omni-repellency, concerted multi-function, and desirable durability remains a daunting challenge. Here, a highly comprehensive coating is designed based on the combination of structural design and molecular design. The resulting silica hybrid coating not only manifests enhanced transparency and exceptional omniphobicity, but also achieves integration of multi-function (e.g., anti-smudge, anti-icing, and anti-corrosion). The unprecedented durability of the coating is evidenced by maintaining slipperiness after rigorous treatments, such as 2.5 × 105-cycle mechanical abrasion with a high loading pressure of 100 kPa, 1000-cycle adhesion/peeling and soaking in extreme pH solutions, etc. This work provides a design blueprint for manufacturing versatile and durable coatings for wide-ranging applications.

15.
ACS Nano ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39051973

RESUMO

The significance of synthetic foams as insulative materials stems from their mechanical and water resistance as well as their cost-effectiveness. Broadly, the design of building envelopes should also consider fire and mold resistance and the impacts on the environment (end of life and compostability). This study addresses these issues considering the ever-increasing demand for sustainable sources to develop highly porous insulative materials. We introduce a versatile strategy based on wet-foam laying of cellulosic fibers that leads to hierarchical structures whose performance is tailored by the surface incorporation of betulin (BT), a bioactive molecule extracted from tree bark, combined with poly(dimethylsiloxane) (PDMS) after installation of urethane linkages. As such, we introduce an eco-friendly alternative to traditional polyurethane foams with competitive mechanical and thermal insulation performance. The modification of the fiber foams at low BT loading simultaneously endows superhydrophobicity (water contact angle >150°), fire retardancy (self-extinguish within 10 s), microbial resistance, and durability (no degradation in soil conditions after 3 months). BT plays a critical role as an antimicrobial and hydrophobic agent that synergizes with PDMS to achieve fire resistance. The life cycle assessment of the BT-modified foams reveals a significant reduction in greenhouse gas emission and human toxicity compared with rigid polyurethane foams by 96 and 92%, respectively. Overall, the valorization of the bark-derived BT is demonstrated by considering the scalability and cost-effectiveness of solid foams designed to substitute petroleum-derived counterparts.

16.
Entropy (Basel) ; 26(6)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38920456

RESUMO

The work here studies the communication cost for a multi-server multi-task distributed computation framework, as well as for a broad class of functions and data statistics. Considering the framework where a user seeks the computation of multiple complex (conceivably non-linear) tasks from a set of distributed servers, we establish the communication cost upper bounds for a variety of data statistics, function classes, and data placements across the servers. To do so, we proceed to apply, for the first time here, Körner's characteristic graph approach-which is known to capture the structural properties of data and functions-to the promising framework of multi-server multi-task distributed computing. Going beyond the general expressions, and in order to offer clearer insight, we also consider the well-known scenario of cyclic dataset placement and linearly separable functions over the binary field, in which case, our approach exhibits considerable gains over the state of the art. Similar gains are identified for the case of multi-linear functions.

17.
ACS Appl Mater Interfaces ; 16(27): 35716-35722, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38917377

RESUMO

Low detectability and camouflage skills in the electromagnetic wave and light frequency range provide survival advantages for natural creatures and are essential for understanding the operational principles of the biosphere. Taking inspiration from natural mutualistic symbiosis, this paper proposes a symbiotic electromagnetic shadow camouflage mechanism based on a superdispersive surface, aiming to investigate its impact on the observability of specific objects. The design and experimental results indicate that the symbiotic shadow dihedral can significantly reduce overall scattering quantity, which reaches at least 10 dB shrink in the 12-18 GHz frequency range compared to the contrast object. Unlike known camouflage methods, the electromagnetic shadow technology shrinks the overall scattering without any coating and shield metal target while probably offering extensive functional design freedom for the concealed object, creature, or equipment. This also provides a hint to explore symbiosis-related camouflage phenomena in nature.

18.
Int J Biol Macromol ; 274(Pt 2): 133405, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38925186

RESUMO

Cellulose nanocrystals (CNCs) were obtained from the extraction and bleaching of jute cellulose as the enhancer, 2-hydroxypropyl-ß-cyclodextrin (HP-ß-CD) as the carrier, the flavonoids-anthocyanidins and cinnamaldehyde as the bioactive agent, and finally a novel kind of polylactic acid (PLA)-based composite membrane was derived by electrostatic spun method. With the increasing concentration, HP-ß-CDs cooperated with CNCs to regulate or control the release rate of bioactive compounds, which had a synergistic effect on the performance of the PLA matrix. The mechanical strength of PLA-3.2 composite with tannic acid (TA) surface cross-linking was 29.6 % higher than neat PLA, and could also continuously protect cells from oxidative stress and free radicals. In addition, excellent cell biocompatibility was found, and attributed to the interaction between bioactive compounds and cell membrane. In addition, we also found two excellent properties from our experimental results: obvious intelligent color reaction and good antibacterial ability. Finally, PLA-3.2 composites could be degraded by soil and are conducive to plant root growth. Hence, this work could solve many of the current problems of biodegradability and functionality of biopolymers for potential applications in areas such as intelligent bioactive food packaging.


Assuntos
2-Hidroxipropil-beta-Ciclodextrina , Celulose , Embalagem de Alimentos , Nanopartículas , Poliésteres , Eletricidade Estática , Celulose/química , Embalagem de Alimentos/métodos , Poliésteres/química , Nanopartículas/química , 2-Hidroxipropil-beta-Ciclodextrina/química , Antibacterianos/farmacologia , Antibacterianos/química
19.
Heliyon ; 10(10): e31118, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38770332

RESUMO

Electromagnetic interference (EMI) shielding material is the most effective solution to protect electronic devices and human health from the harmful effects of electromagnetic radiation. The study of EMI shielding materials is intensifying in the constantly developing picture of the fourth industrial revolution. Many EMI shielding materials based on metal, carbon, emerging MXene materials, and their composites have been discovered to utilize the EMI shielding performance. However, a huge demand for compact and multi-functional devices requires the integration of new functions into EMI shielding materials. Multifunctional EMI shielding materials perform multiple functions beyond their main function of EMI shielding in a system due to their specific properties. The additional functions can either naturally exist or be specially engineered. This review summarizes the recent progress of cutting-edge multifunctional EMI shielding materials. The possibility of combining multifunction EMI shielding materials, such as strain sensing, humidity sensing, temperature sensing, thermal management, etc., and the difficulties in balancing EMI shielding performance with other functions are also discussed. Lastly, we point out challenges and propose future directions to develop research on multifunctional EMI shielding materials.

20.
Chemphyschem ; 25(17): e202400297, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-38797706

RESUMO

Materials that integrate magnetism, electricity and luminescence can not only improve the operational efficiency of devices, but also potentially generate new functions through their coupling. Therefore, multifunctional synergistic effects have broad application prospects in fields such as optoelectronic devices, information storage and processing, and quantum computing. However, in the research field of molecular materials, there are few reports on the synergistic multifunctional properties. The main reason is that there is insufficient awareness of how to obtain such material. In this brief review, we summarized the molecular materials with this characteristic. The structural phase transition of substances will cause changes in their physical properties, as the electronic configurations of the active unit in different structural phases are different. Therefore, we will classify and describe the multifunctional synergistic complexes based on the structural factors that cause the first-order phase transition of the complexes. This enables us to quickly screen complexes with synergistic responses to these properties through structural phase transitions, providing ideas for studying the synergistic response of physical properties in molecular materials.

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