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1.
Opt Lett ; 47(18): 4746-4749, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36107080

RESUMO

Stimulated emission depletion (STED) microscopy achieved with lanthanide-doped upconversion nanoparticles (UCNPs) exhibits many outstanding advantages such as low-power illumination, near-infrared (NIR) excitation, and high photostability. However, the available types of UCNP-STED probes are very limited and rely greatly on the specific depletion mechanism. Here, by combining the STED and the energy migration upconversion processes, emissions of Tb3+, Eu3+, Dy3+, and Sm3+ distributed in the shell can all be depleted by interrupting the injected energy flux from the Tm3+-doped core nanoparticles. With the merit of the proposed strategy, new types of UCNP-STED probes are demonstrated to perform emission-varying STED imaging with one single, fixed pair of low-power NIR continuous wave lasers.


Assuntos
Elementos da Série dos Lantanídeos , Nanopartículas , Raios Infravermelhos , Microscopia , Fenômenos Físicos
2.
Nat Commun ; 13(1): 5349, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36097265

RESUMO

Increased occurrence of heatwaves across different parts of the world is one of the characteristic signatures of anthropogenic warming. With a 1.3 billion population, India is one of the hot spots that experience deadly heatwaves during May-June - yet the large-scale physical mechanism and teleconnection patterns driving such events remain poorly understood. Here using observations and controlled climate model experiments, we demonstrate a significant footprint of the far-reaching Pacific Meridional Mode (PMM) on the heatwave intensity (and duration) across North Central India (NCI) - the high risk region prone to heatwaves. A strong positive phase of PMM leads to a significant increase in heatwave intensity and duration over NCI (0.8-2 °C and 3-6 days; p < 0.05) and vice-versa. The current generation (CMIP6) climate models that adequately capture the PMM and their responses to NCI heatwaves, project significantly higher intensities of future heatwaves (0.5-1 °C; p < 0.05) compared to all model ensembles. These differences in the intensities of heatwaves could significantly increase the mortality (by ≈150%) and therefore can have substantial implications on designing the mitigation and adaptation strategies.


Assuntos
Aclimatação , Raios Infravermelhos , Índia , Oceano Pacífico , Estações do Ano
3.
Acc Chem Res ; 55(18): 2604-2615, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36074952

RESUMO

ConspectusPhoton upconversion, the process of converting low-energy photons into high-energy ones, has been widely applied for solar energy conversion, photoredox catalysis, and various biological applications such as background-free bioimaging, cancer therapy, and optogenetics. Upconversion materials that are based on triplet-triplet annihilation (TTA) are of particular interest due to their low excitation power requirements (e.g., ambient sunlight) and easily tunable excitation and emission wavelengths. Despite advances that have been made with respect to TTA upconversion (TTA-UC) in the past decade, several challenges remain for near-infrared light-activatable triplet-triplet annihilation upconversion (NIR TTA-UC). These challenges include low upconversion quantum yield, small anti-Stokes shift, and incompatibility with oxygen, the latter of which seriously limits the practical applications of NIR TTA-UC.This Account will summarize the recent research endeavors to address the above-mentioned challenges and the recent new applications. The first part of this Account highlights recent strategies of molecular design to modulate the excited states of photosensitizers and annihilators, two key factors to determine TTA-UC performance. Novel molecular engineering strategies such as the resonance energy transfer method, dimerization of dye units, and the helix twist molecular structure have been proposed to tune the excited states of photosensitizers. The obtained photosensitizers exhibited enhanced absorption of deep tissue penetrable near-infrared (NIR) light, produced a triplet excited state with elevated energy level and prolonged lifetime, and promoted intersystem crossing, leading to an upgraded TTA-UC system with significantly expanded anti-Stokes shift. With respect to the annihilator, the perylene derivatives were systematically explored, and their attached aromatic groups were found to be the key to adjusting the energy levels of both the triplet and singlet excited states. The resultant optimal TTA-UC system exhibits the highest recorded efficiency among NIR TTA-UC systems.Moreover, to resolve the oxygen-induced TTA-UC quenching, enzymatic reactions were recently introduced. More specifically, the glucose oxidase-catalyzed glucose oxidation reaction showed the ability to rapidly consume oxygen to turn on the TTA-UC luminescence in an aqueous solution. The resultant TTA-UC nanoparticle was able to detect glucose and an enzyme related to glucose metabolism in a highly specific, sensitive, and background-free manner. Further, the upconverted singlet excited state of the annihilator was directly utilized as the catalyst or the excited substrate. For example, the modification of annihilators and drug molecules with photolabile linkages can realize the long wavelength light-induced photolysis. Compared to direct short-wavelength-driven photolysis, this sensitized TTA photolysis (TTAP) exhibits superior reaction yield and lower photodamage, which are important in the release of drugs for tumor treatment in vivo. Moreover, the improved upconversion efficiency can enable the successful coupling of NIR TTA-UC with a visible light absorbing photocatalyst for NIR-driven photoredox catalysis. Compared to direct visible-light photocatalysis, TTA-UC mediated NIR photoredox catalysis showed superior product yield especially in large scale reaction systems owing to the deep penetration power of NIR light. More interestingly, among a few promising technology applications, three-dimensional (3D) printing based on photopolymerization can operate with faster speed and energy-input several orders of magnitude lower when the two-photon polymerization is replaced with TTA-UC mediated polymerization. We believe this Account will spur interest in the further development and application of TTA-UC in the areas of energy, chemistry, material science, and biology.


Assuntos
Perileno , Fármacos Fotossensibilizantes , Glucose , Glucose Oxidase , Raios Infravermelhos , Oxigênio/química , Fármacos Fotossensibilizantes/química
4.
Biomacromolecules ; 23(9): 3602-3611, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-35930811

RESUMO

Despite the wide investigation on black phosphorus (BP) for biophotonic applications, the finite depth of light penetration has limited further development of BP-based photomedicines. Here, we developed a hyaluronate-BP-upconversion nanoparticle (HA-BP-UCNP) complex for near-infrared (NIR) light-mediated multimodal theranosis of skin cancer with photoacoustic (PA) bioimaging, photodynamic therapy (PDT), and photothermal therapy (PTT). In contrast to the conventional BP-based skin cancer theranosis, the HA-BP-UCNP complex could be non-invasively delivered into the tumor tissue to induce the cancer cell apoptosis upon NIR light irradiation. The PA imaging of BP successfully visualized the non-invasive transdermal delivery of the HA-BP-UCNP complex into the mice skin. HA in the complex facilitated the transdermal delivery of BP into the tumor tissue under the skin. Upon 980 nm NIR light irradiation, the UCNP converted the light to UV-blue light to generate reactive oxygen species by sensitizing BP in the HA-BP-UCNP complex for PDT. Remarkably, 808 nm NIR irradiation with PTT triggered the apoptosis of tumor cells. Taken together, we could confirm the feasibility of the HA-BP-UCNP complex for NIR light-mediated multimodal theranosis of skin cancers.


Assuntos
Nanopartículas , Fotoquimioterapia , Neoplasias Cutâneas , Animais , Raios Infravermelhos , Camundongos , Fósforo , Fotoquimioterapia/métodos , Neoplasias Cutâneas/tratamento farmacológico
5.
Sensors (Basel) ; 22(16)2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-36015902

RESUMO

The understanding of blast loads is critical for the development of infrastructure that protects against explosions. However, the lack of high-quality experimental work on the characterisation of such loads prevents a better understanding of many scenarios. Blast loads are typically characterised by use of some form of pressure gauge, from which the temperature can be inferred from a pressure measurement. However, such an approach to temperature measurement is limited; it assumes ideal gas laws apply throughout, which may not be the case for high temperature and pressure scenarios. In contrast, infrared radiation thermometers (IRTs) perform a measurement of temperature based upon the emitted radiance from the target object. The IRTs can measure fast changes in transient temperature, making them seemingly ideal for the measurement of a fireball's temperature. In this work, we present the use of a high-speed IRT for the measurement of early-stage explosive development and fireball expansion within a confined blast, with the temperature of the explosive fireball measured from its emitted radiance. The temperature measured by the IRT was corroborated against the temperature inferred from a pressure gauge measurement; both instruments measured the same temperature from the quasi-static pressure (QSP) point onwards. Before the QSP point, it is deduced that the IRT measures the average temperature of the fireball over a wide field-of-view (FOV), as opposed to that inferred from the singular shocks detected by the pressure gauge. Therefore, use of an IRT, in tandem with a pressure gauge, provides a potential invaluable measurement technique for the characterisation the early stages of a fireball as it develops and expands.


Assuntos
Substâncias Explosivas , Termômetros , Temperatura Corporal , Febre , Humanos , Raios Infravermelhos
6.
Int J Biol Macromol ; 218: 1013-1020, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35926670

RESUMO

Heat stimulation can promote osteoblast differentiation and bone formation. Combining photothermal therapy and chemotherapy is an effective strategy for treating rheumatoid arthritis (RA). Herein, we prepared chitosan/gelatin/ß-glycerophosphate-melanin-methotrexate (CMM) hydrogel that could be used to perform simultaneous chemotherapy and photothermal therapy for patients with RA. The CMM solution was successfully converted to a gel state at body temperature. Due to intrinsic photothermal properties of melanin, CMM hydrogel exhibited effective temperature increase both in vitro and in vivo with increasing time of near-infrared (NIR) laser irradiation. After NIR laser irradiation, 50 % of methotrexate was rapidly released from the hydrogel within 3 h. Its release rate showed an instantaneous increase with additional NIR laser irradiation. After CMM hydrogel was injected directly into the paw joint of each collagen-induced arthritis (CIA) mouse followed by irradiation with a NIR laser (808 nm, 0.5 W/cm2, 3 min), swelling and redness at the inflamed area were significantly alleviated at 14 days after treatment. Micro-CT analysis confirmed that treated joints of mice were similar to normal joints. Hence, CMM hydrogel could be used as an attractive RA therapeutic agent for simultaneous chemo-photothermal therapy.


Assuntos
Artrite Experimental , Quitosana , Animais , Artrite Experimental/tratamento farmacológico , Modelos Animais de Doenças , Doxorrubicina/farmacologia , Gelatina , Hidrogéis/farmacologia , Raios Infravermelhos , Melaninas , Metotrexato/farmacologia , Camundongos , Fototerapia
7.
Vet Rec ; 191(3): 100, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35929681
8.
J Photochem Photobiol B ; 234: 112533, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35914465

RESUMO

Water-filtered infrared A (wIRA) alone or in combination with visible light (VIS) exerts anti-chlamydial effects in vitro and in vivo in acute infection models. However, it has remained unclear whether reduced irradiation duration and irradiance would still maintain anti-chlamydial efficacy. Furthermore, efficacy of this non-chemical treatment option against persistent (chronic) chlamydial infections has not been investigated to date. To address this knowledge gap, we evaluated 1) irradiation durations of 5, 15 or 30 min in genital and ocular Chlamydia trachomatis acute infection models, 2) irradiances of 100, 150 or 200 mW/cm2 in the acute genital infection model and 3) anti-chlamydial activity of wIRA and VIS against C. trachomatis serovar B and E with amoxicillin (AMX)- or interferon γ (IFN-γ)-induced persistence. Reduction of irradiation duration reduced anti-chlamydial efficacy. Irradiances of 150 to 200 mW/cm2, but not 100 mW/cm2, induced anti-chlamydial effects. For persistent infections, wIRA and VIS irradiation showed robust anti-chlamydial activity independent of the infection status (persistent or recovering), persistence inducer (AMX or IFN-γ) or chlamydial strain (serovar B or E). This study clarifies the requirement of 30 min irradiation duration and 150 mW/cm2 irradiance to induce significant anti-chlamydial effects in vitro, supports the use of irradiation in the wIRA and VIS spectrum as a promising non-chemical treatment for chlamydial infections and provides important information for follow-up in vivo studies. Notably, wIRA and VIS exert anti-chlamydial effects on persistent chlamydiae which are known to be refractory to antibiotic treatment.


Assuntos
Raios Infravermelhos , Água , Interferon gama
9.
J Photochem Photobiol B ; 234: 112530, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35930949

RESUMO

In this study, we develop a characterization of bacterial spore resistance to NIR pulsed light under modalities traditionally used in multiphoton microscopy. Energy dose and laser power are both key parameters in spore and bacterial cell inactivation. Surprisingly, spores and vegetative cells seem to show a similar sensitivity to pulsed NIR, spores being only 2-fold more resistant than their vegetative counterparts. This work enables us to eliminate certain hypotheses concerning the main driver of spore inactivation processes. Our findings suggest that damage leading to inactivation is mainly caused by photochemical reactions characterized by multiple possible pathways, including DNA damage or oxidation processes.


Assuntos
Bacillus subtilis , Esporos Bacterianos , Bacillus subtilis/fisiologia , Dano ao DNA , Raios Infravermelhos , Esporos Bacterianos/fisiologia
10.
Artigo em Inglês | MEDLINE | ID: mdl-36011875

RESUMO

This article reports a thermal analysis of the wrists to analyze the behavior and recovery of skin temperature after 20 min when performing a highly repetitive movement, and two thermography methods (sensory and infrared) and research groups were compared. The tests were carried out with 44 participants who performed a repetitive task for 10 min and integrated into two groups, of which 22 were trained workers from a maquiladora company and were analyzed with sensory thermography, and the other 22 were in the laboratory with infrared thermography with undergraduate students. The study area is the left and right hand, specifically the wrists. The proposed hypothesis is that people with some musculoskeletal problems have a decrease in temperature when starting repetitive tasks and thermal asymmetries, which measurements were recorded at 0, 10, 15, and 20 min after the task was finished. Findings indicate that the temperatures in both wrists behave similarly. The workers reached higher temperatures, and the centigrade degrees of asymmetry difference were also higher. The variable with influence on the temperature was fractured in the arm. After thermally analyzing the temperature behavior between the wrists of both hands, it is concluded that there is an increase in temperature after finishing a repetitive task, and it does not stabilize after 20 min. Both thermography methods observed that the asymmetries are greater than 0.5 °C, detecting the possible pathology of carpal tunnel syndrome.


Assuntos
Termografia , Punho , Mãos , Humanos , Raios Infravermelhos , Temperatura Cutânea , Temperatura , Termografia/métodos
11.
Photobiomodul Photomed Laser Surg ; 40(9): 604-612, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36040390

RESUMO

Objective: Bee populations are under threat from diverse sources from climate change to insecticide use. These culminate in physiological stress undermining mitochondrial function. In laboratory environments, mitochondrial stress can be ameliorated by long wavelength light that protects insects individually against stress. In this study, we ask if these results can be translated to large insect communities and complex environments in the form of field honeybee hives. Materials and methods: We embed 670 nm light devices into honeybee hives in the field, and in sampled populations measure mitochondrial function, resistance to insecticide exposure, and the maintenance of hive temperatures in challenging summer conditions. Results: We show that 670 nm light increases the mitochondrial function and protects bees when they are exposed to imidacloprid in the winter supplementary feed. Hives with 670 nm lights maintained stable temperatures compared with controls in adverse weather conditions. Conclusions: This proof-of-principal study opens the door to widespread use of long wavelength light to protect honeybee hives from the increasing threats undermining their physiology that can cause colony collapse.


Assuntos
Inseticidas , Urticária , Animais , Abelhas , Raios Infravermelhos , Mitocôndrias , Temperatura
12.
ACS Appl Mater Interfaces ; 14(32): 36947-36956, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35929762

RESUMO

Bacterial infection is seriously threatening human health, and the design of high-efficiency and good biocompatibility antibacterial agents is an urgent problem to be solved. However, with the emergence of drug-resistant bacteria, the existing antibacterial agents have low killing efficiency, and the formation of biofilms has further weakened the therapeutic effect. Herein, we constructed an efficient antibacterial system mediated by near-infrared light for synergistic antibacterial and biofilm dissipation. Specifically, the ZnO/Ti3C2Tx with heterojunction was synthesized by hydrothermal growth of ZnO on the surface of lamellar Ti3C2Tx-MXene. The prepared ZnO/Ti3C2Tx had better photothermal ability than ZnO and Ti3C2Tx, respectively. The local thermal effect can not only destroy the integrity of the bacterial membrane but also promote the release of Zn2+ ions and further improve the antibacterial performance. ZnO/Ti3C2Tx achieved a 100% sterilization rate (better than either ZnO or Ti3C2Tx) at 150 µg mL-1. The biofilm dissipation experiment further proved its excellent biofilm ablation effect. More importantly, the results of in vitro cell culture and animal experiments have demonstrated its good biological safety. In summary, this new type of nanomaterial shows strong local chemical photothermal sterilization ability and has great potential to replace traditional antibacterial agents.


Assuntos
Óxido de Zinco , Animais , Antibacterianos/farmacologia , Bactérias , Biofilmes , Humanos , Raios Infravermelhos , Óxido de Zinco/farmacologia
13.
Anal Chem ; 94(35): 12024-12032, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-35994569

RESUMO

Manipulating cell-cell interactions is of great significance in cell communication and cell-based therapies. Although efforts have been made to construct cell-cell assembly by stimuli-responsive host-guest interactions, controllable cell-cell interactions by near-infrared (NIR) light triggered reversible assembly remain a challenge. Herein, we develop a NIR-controlled system based on ß-cyclodextrin (ß-CD) modified upconversion nanoparticles (UCNPs) for reversible and noninvasive manipulation of cell assembly and disassembly, which is realized by host-guest interactions between E/Z-photoisomerization of arylazopyrazole (AAP) and ß-CD under the NIR irradiation. UCNPs can convert NIR to ultraviolet light, which leads to the transformation of AAP from the E-isomer to the Z-isomer. And it can be reverted back to the E-isomer under visible light irradiation. This reversible photoisomerization can modulate the host-guest interaction between ß-CD and AAP, thus leading to reversible cell assembly and disassembly. Furthermore, by precise regulating cell-cell interactions by NIR light, cell-cell communication and molecular transportation can be realized. Given the diversity of host and guest molecules and the advantages of NIR light in biological applications, reversible cell-cell assembly has great potential for the regulation of cell behaviors and cell-based therapies.


Assuntos
Raios Infravermelhos , Nanopartículas , Comunicação Celular , Raios Ultravioleta
14.
Adv Sci (Weinh) ; 9(26): e2202505, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35853243

RESUMO

Exploring the advanced techniques for protein detection facilitates cell fate investigation. However, it remains challenging to quantify and visualize the protein with one single probe. Here, a luminescent approach to detect hepatic cell fate marker albumin in vitro and living cell labeling with upconversion nanoparticles (UCNPs), which are conjugated with antibody (Ab) and rose bengal hexanoic acid (RBHA) is reported. To guarantee the detection quality and accuracy, an "OFF-ON" strategy is adopted: in the presence of albumin, the luminescence of nanoparticles remains suppressed owing to energy transfer to the quencher. Upon albumin binding to the antibody, the luminescence is recovered under near-infrared light. In various bio-samples, the UCNPs-Ab-RBHA (UCAR) nanoprobe can sense albumin with a broad detection range (5-315 ng mL-1 ). When applied to liver ductal organoid culture medium, the UCAR can monitor hepatocyte differentiation in real time by sensing the secreted albumin. Further, UCAR enables live imaging of cellular albumin in cells, organoids, and tissues. In a CCl4 -induced liver injury model, UCAR detects reduced albumin in liver tissue and serum. Thus, a biocompatible nanoprobe for both quantification and imaging of protein in complex biological environment with superior stability and high sensitivity is provided.


Assuntos
Nanopartículas , Organoides , Albuminas , Animais , Raios Infravermelhos , Fígado , Camundongos
15.
J Adv Res ; 39: 167-185, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35777907

RESUMO

INTRODUCTION: Nanofluids are considered a better alternative to conventional fluids in many industrial situations and unfolding new opportunities for various applications owing to the optical and thermal properties of additive nanosized materials. OBJECTIVES: In this study, the thermal and hydraulic characteristics of a Casson-based (sodium alginate) multiwall carbon nanotube (MWCNT) nanofluid were computationally investigated inside a wavy square enclosure containing a circular-shaped obstacle. The square enclosure comprised two cooled vertical walls and a wavy adiabatic top wall. The central part of the bottom wall comprised a heated wavy structure, and the remaining parts exhibited a flat and adiabatic structure. METHODS: The Navier-Stokes (N-S) equations and boundary conditions were established using the non-Newtonian Casson fluid model and Rosseland thermal radiation. The present problem was numerically simulated using the Galerkin finite element method for three types of obstacles, namely, adiabatic, hot, and cold. The impacts of Casson parameter (0.001 ≤ ß ≤ 0.1), Rayleigh number (103 ≤ Ra ≤ 106), nanoparticle volume fraction (0.01 ≤ φ ≤ 0.1) and radiation parameter (1 ≤ Rd ≤ 4) are analysed. A numerical code validation was performed using the available benchmark results. RESULTS: The characteristics of the convective radiation heat transport were clearly analyzed through the stream function and isotherm plots. For all types of obstacles, the mean Nusselt number along the heated wavy wall increased with the Casson parameter, MWCNT volume fraction, Rayleigh number, and radiation parameter. CONCLUSION: The heat and flow characteristics of a Casson-based MWCNT nanofluid inside a wavy square enclosure were investigated. The mean Nusselt number was higher (lower) in the presence of cold (hot) obstacles.


Assuntos
Nanopartículas , Nanotubos de Carbono , Convecção , Temperatura Alta , Raios Infravermelhos
16.
Molecules ; 27(13)2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35807299

RESUMO

Near-infrared (NIR) light-triggered photoredox catalysis is highly desirable because NIR light occupies almost 50% of solar energy and possesses excellent penetrating power in various media. Herein we utilize a metal-free boron dipyrromethene (BODIPY) derivative as the photocatalyst to achieve NIR light (720 nm LED)-driven oxidation of benzylamine derivatives, sulfides, and aryl boronic acids. Compared to blue light-driven photooxidation using Ru(bpy)3Cl2 as a photocatalyst, NIR light-driven photooxidation exhibited solvent independence and superior performance in large-volume (20 mL) reaction, presumably thanks to the neutral structure of a BODIPY photocatalyst and the deeper penetration depth of NIR light. We further demonstrate the application of this metal-free NIR photooxidation to prodrug activation and combination with Cu-catalysis for cross coupling reaction, exhibiting the potential of metal-free NIR photooxidation as a toolbox for organic synthesis and drug development.


Assuntos
Raios Infravermelhos , Luz , Ácidos Borônicos , Catálise , Oxirredução , Sulfetos
17.
J Phys Chem Lett ; 13(28): 6571-6579, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35833756

RESUMO

Developing a suitable initiation for the energetic materials that respond to a low-power near-infrared laser can aid in replacing the current expensive and bulky laser-initiation systems. Here, we report on a system of molecularly tailored 1:1 donor-acceptor (D-A) charge-transfer (CT) cocrystals that manifest ultrabroad absorption (200-2500 nm) characteristics as well as noteworthy very fast self-assembly behaviors. The very narrow highest occupied molecular orbital-lowest unoccupied molecular orbital gap enables N,N,N',N'-tetramethyl-p-phenylenediamine and tetrahalo-1,4-benzoquinones (TMPD-TXBQ) cocrystals to have a great light-harvesting ability in the near-infrared range. When irradiated with a low-power hand-held 808 nm laser with an input energy of only 40 mJ or a power density of 260 mW·cm-2, these TMPD-TXBQ cocrystals immediately undergo an efficient photothermal conversion followed by a dramatic exothermic thermal polymerization reaction due to the face-to-face D-A-D-A stacking in these cocystals to achieve a temperature as high as 318.9 °C. This temperature is high enough for a thermal initiation of most common energetic materials, and thus this TMPD-TXBQ cocrystal can potentially act as a near-infrared laser initiator that is compact, lightweight, and cost-effective.


Assuntos
Temperatura Alta , Raios Infravermelhos , Lasers , Temperatura
18.
Nat Commun ; 13(1): 3851, 2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35788585

RESUMO

Persistent heat extremes can have severe impacts on ecosystems and societies, including excess mortality, wildfires, and harvest failures. Here we identify Europe as a heatwave hotspot, exhibiting upward trends that are three-to-four times faster compared to the rest of the northern midlatitudes over the past 42 years. This accelerated trend is linked to atmospheric dynamical changes via an increase in the frequency and persistence of double jet stream states over Eurasia. We find that double jet occurrences are particularly important for western European heatwaves, explaining up to 35% of temperature variability. The upward trend in the persistence of double jet events explains almost all of the accelerated heatwave trend in western Europe, and about 30% of it over the extended European region. Those findings provide evidence that in addition to thermodynamical drivers, atmospheric dynamical changes have contributed to the increased rate of European heatwaves, with implications for risk management and potential adaptation strategies.


Assuntos
Ecossistema , Raios Infravermelhos , Adaptação Fisiológica , Temperatura Alta , Temperatura
19.
ACS Appl Bio Mater ; 5(8): 3841-3849, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35815771

RESUMO

Light-responsive nanocarrier-based drug delivery systems (NDDSs), due to their unique advantages such as safety, minimal cross-reaction, and spatiotemporal precision, have received wide attention. Notably, second near-infrared (NIR-II) light, which has a high penetration depth for manipulating NDDSs to release drugs, is in high demand. Herein, polyethylene glycol (PEG)-modified hollow CuxS nanoparticles (NPs) are developed as an all-in-one NIR-II light-responsive NDDS for synergistic chemo-photothermal therapy. First, CuxS-PEG NPs were prepared under mild conditions by using Cu2O NPs as sacrificial templates. The morphology, photothermal effect, drug loading/releasing abilities, and synergistic chemo-photothermal therapy of CuxS-PEG NPs have been investigated. The CuxS-PEG NPs with hollow structures showed a high drug loading capacity (∼255 µg Dox per mg of CuxS NPs) and stimuli-responsive drug release triggered by NIR-II laser irradiation. The synergistic chemo-photothermal therapy based on the Dox/CuxS-PEG NPs showed 98.5% tumor elimination. Our study emphasizes the great potential of CuxS-PEG NPs as an all-in-one NIR-II light-responsive NDDS for applications in biomedicine.


Assuntos
Doxorrubicina , Terapia Fototérmica , Sistemas de Liberação de Medicamentos , Raios Infravermelhos , Fototerapia , Polietilenoglicóis/química
20.
Small ; 18(33): e2203821, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35867042

RESUMO

2D layered molybdenum disulfide (MoS2 ) nanomaterials are a promising platform for biomedical applications, particularly due to its high biocompatibility characteristics, mechanical and electrical properties, and flexible functionalization. Additionally, the bandgap of MoS2 can be engineered to absorb light over a wide range of wavelengths, which can then be transformed into local heat for applications in photothermal tissue ablation and regeneration. However, limitations such as poor stability of aqueous dispersions and low accumulation in affected tissues impair the full realization of MoS2 for biomedical applications. To overcome such challenges, herein, multifunctional MoS2 -based magnetic helical microrobots (MoSBOTs) using cyanobacterium Spirulina platensis are proposed as biotemplate for therapeutic and biorecognition applications. The cytocompatible microrobots combine remote magnetic navigation with MoS2 photothermal activity under near-infrared irradiation. The resulting photoabsorbent features of the MoSBOTs are exploited for targeted photothermal ablation of cancer cells and on-the-fly biorecognition in minimally invasive oncotherapy applications. The proposed multi-therapeutic MoSBOTs hold considerable potential for a myriad of cancer treatment and diagnostic-related applications, circumventing current challenges of ablative procedures.


Assuntos
Molibdênio , Nanoestruturas , Dissulfetos , Raios Infravermelhos , Fototerapia/métodos
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