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1.
Anal Chem ; 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39313954

RESUMO

Creatinine is an important biomarker of kidney function and muscular metabolism. In this paper, we developed the ß-lead dioxide/single-walled carbon nanotube (ß-PbO2/CNT) and the ß-PbO2/CNT ion-selective electrode (ß-PbO2/CNT/ISE), which were used as highly sensitive potentiometric sensors for creatinine detection. The fabricated electrodes exhibited highly pH-sensitive characteristics due to the synergistic effect of the electrochemical properties of CNT and ß-PbO2. Moreover, an ammonium-ion-selective membrane coating allowed the ß-PbO2/CNT electrode to be NH4+-selective for direct detection of the ammonium ion. By exploiting the electrochemical characteristics of these electrodes, the creatinine assay was established through the one-step selective conversion of creatinine by creatinine deiminase, in which the OH- and NH4+ generated by the enzymatic reaction were detected using ß-PbO2/CNT and ß-PbO2/CNT/ISE electrodes as pH- and NH4+-responsive sensors, respectively. The total creatinine assay can be completed within ∼5 min. The assay results from ß-PbO2/CNT and ß-PbO2/CNT/ISE showed excellent sensitivity values of -75.56 and 64.62 mV in the detection range of 10-400 µM with a fast response (20 s), and the limits of detection were calculated to be 0.06 and 0.13 µM, respectively. Moreover, the developed creatinine sensor showed high selectivity against 11 interfering bio/chemical species with negligible interferences (selectivity coefficient <10-4) and excellent repeatability (>97% within 25 cycles) and long-term stability for 4 weeks of storage. In addition, the feasibility and practicality of the device were successfully demonstrated in human serum tests, with recoveries of 95-104% for PbO2/CNT and 92-110% for PbO2/CNT/ISE.

2.
Sci Adv ; 10(38): eadp2809, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39292769

RESUMO

Biologically inspired artificial vision research has led to innovative robotic vision systems with low optical aberration, wide field of view, and compact form factor. However, challenges persist in object detection and recognition against complex backgrounds and varied lighting. Inspired by the feline eye, which features a vertically elongated pupil and tapetum lucidum, this study introduces an artificial vision system designed for superior object detection and recognition in a monocular framework. Using a slit-like elliptical aperture and a patterned metal reflector beneath a hemispherical silicon photodiode array, the system reduces excessive light and enhances photosensitivity. This design achieves clear focus under bright light and enhanced sensitivity in dim conditions. Theoretical and experimental analyses demonstrate the system's ability to filter redundant information and detect camouflaged objects in diverse lighting, representing a substantial advancement in monocular camera technology and the potential of biomimicry in optical innovations.

3.
J Int Adv Otol ; 20(4): 331-338, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39161176

RESUMO

Eosinophilic otitis media, first reported in Japan, is a viscous, intractable otitis media often linked to bronchial asthma and chronic rhinosinusitis, characterized by highly viscous middle ear effusion. Its pathological mechanism remains unclear and the condition occasionally does not respond to steroids. It is now recognized as a rare type 2 inflammatory disease and should be treated specifically to enhance quality of life. This systematic review and meta-analysis evaluated the efficacies of biologic treatments. We searched PubMed, SCOPUS, Embase, Web of Science, and Cochrane databases up to September 2023. We retrieved ear examination findings, otitis media-related and symptom scores, air-bone gaps and hearing thresholds, serum eosinophil, and immunoglobulin E (IgE) levels before and after biologic treatments. Biologics treatment significantly improved subjective otitis media-related scores, compared with control group (standard mean difference (SMD) -1.62; 95% confidence interval (CI) [-2.24; -1.01], I2=54%). Additionally, the serum eosinophil counts and IgE levels significantly decreased (SMD -1.40; 95% CI [-1.99; -0.81], I 2=0%) after 6-12 months of biologic treatments, but the hearing thresholds did not significantly change. There were no significant differences between groups treated with dupilumab and groups treated with other biologics. Biologics treatment for eosinophilic otitis media significantly improved subjective otitis media-related scores and decreased serum eosinophil and IgE levels, but no significant changes in hearing threshold. More randomized cohort studies are needed to confirm the efficacies of biologics in patients with refractory eosinophilic otitis media.


Assuntos
Terapia Biológica , Eosinofilia , Humanos , Terapia Biológica/métodos , Eosinofilia/tratamento farmacológico , Eosinofilia/sangue , Resultado do Tratamento , Imunoglobulina E/sangue , Otite Média/tratamento farmacológico , Otite Média com Derrame/tratamento farmacológico , Eosinófilos , Produtos Biológicos/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Qualidade de Vida
5.
Food Sci Biotechnol ; 33(7): 1707-1714, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38623436

RESUMO

Attempts to improve low absorption and rapid metabolic conversion of curcumin were made by developing curcumin-loaded bilayer nanoliposomes coated with chitosan and alginate for intestinal-specific drug delivery. A curcumin-loaded nano-liposome was prepared with optimized formulations with phosphatidylcholine, curcumin, chitosan, and alginate. The particle size of the optimized formulation was approximately 400 nm, and the encapsulation efficiency was more than 99%. In the in vitro release study, curcumin release from the curcumin-loaded nanoliposome with double layers of chitosan/alginate (CNL-CH/AL) was suppressed in the simulated gastric fluid (SGF, pH 1.2) and enhanced in the simulated intestinal fluid (SIF, pH 6.8). In the in vivo pharmacokinetic study in rats, the CNL-CH/AL-treated group showed a prolonged absorption pattern of curcumin and the area under the plasma concentration-time curve from 0 to 24 h (AUC0-24) was improved 109-fold compared to the control group treated with a curcumin solution without a nanocarrier.

6.
Biosens Bioelectron ; 249: 116007, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38194812

RESUMO

Chitosan (CS)-stabilized platinum nanoparticles (CS/PtNPs) were employed to develop a novel aptamer-based dual-mode colorimetric and photothermal biosensor for selective detection of kanamycin (KAN). As a peroxidase-like catalyst, the CS/PtNPs showed outstanding catalytic activity for the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide (H2O2). As a stabilizing agent, CS excelled at fixing the KAN binding aptamer on the surface of the CS/PtNPs, amplifying their catalytic activity and enhancing colloidal dispersion and stability. The oxidized TMB (TMBox) functioned as a signal for the colorimetric, photothermal aptasensor because of its observable absorbance of light in the visible and near-infrared (NIR) regions. When light from a NIR laser was absorbed by the TMBox in the reaction solution, heat was generated in inverse proportion to the KAN concentration. The developed colorimetric and photothermal modes of the aptasensor showed a linear detection range of 0.1-50 and 0.5-50 µM, with a limit of detection (LOD) of 0.04 and 0.41 µM, respectively. Moreover, the aptasensor successfully determined KAN concentrations in spiked milk samples, verifying the reliability and reproducibility in practical applications. The dual-mode aptasensor based on CS/PtNPs for KAN detection, utilizing both color change and heat generation signals through a single probe (TMBox), demonstrates rapid response, simplicity in operation, cost-effectiveness, and high sensitivity. In addition, unlike typical immunoassays, this aptamer-based peroxidase-like nanozyme activation and inhibition strategy required no washing process, which was very effective in terms of reducing the time required for an assay and sustaining a high sensitivity.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Canamicina , Platina , Reprodutibilidade dos Testes , Colorimetria , Peróxido de Hidrogênio , Peroxidase , Aptâmeros de Nucleotídeos/metabolismo
7.
J Photochem Photobiol B ; 250: 112831, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38134574

RESUMO

Cancer is a life-threatening disease when it is diagnosed at a late stage or treatment procedures fail. Inhibiting cancer cells in the tumor environment is a significant challenge for anticancer therapy. The photothermal effects of nanomaterials are being studied as a new cancer treatment. In this work, rhenium disulfide (ReS2) nanosheets were made by liquid exfoliation with gum arabic (GA) and coated with silver nanoparticles (AgNPs) to produce reactive oxygen species that destroy cancer cells. The synthesized AgNP-GA-ReS2 NPs were characterized using UV, DLS, SEM, TEM, and photothermal studies. According to the DLS findings, the NPs were about 216 nm in size and had a zeta potential of 76 mV. The TEM and SEM analyses revealed that the GA-ReS2 formed single-layered nanosheets on which the AgNPs were distributed. The photothermal effects of the AgNP-GA-ReS2 NPs at 50 µg/mL were tested with an 808 nm laser at 1.2 W cm-2, and they reached 55.8 °C after 5 min of laser irradiation. MBA-MB-231 cells were used to test the cytotoxicity of the newly designed AgNP-GA-ReS2 NPs with and without laser irradiation for 5 min. At 50 µg/mL, the AgNP-GA-ReS2 showed cytotoxicity, which was confirmed with calcein and EtBr staining. The DCFH-DA and flow cytometry analyses demonstrated that AgNP-GA-ReS2 nanosheets under NIR irradiation generated ROS with high anticancer activity, in addition to the photothermal effects.


Assuntos
Nanopartículas Metálicas , Neoplasias , Rênio , Humanos , Nanopartículas Metálicas/toxicidade , Prata/farmacologia
8.
J Endod ; 50(3): 310-315, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38141831

RESUMO

INTRODUCTION: This study investigated endodontically treated teeth that were replaced by dental implants at the University of North Carolina (UNC) at Chapel Hill School of Dentistry. The primary objective of this study was to determine the reasons leading to the extraction of endodontically treated teeth and their subsequent replacement with dental implants. The secondary objective was to evaluate the proportion of these teeth that, according to experienced endodontists, could have been preserved. METHODS: The UNC-Chapel Hill's dental electronic health records between 2004 and 2019 were probed for implant placement that replaced root canal-treated teeth. Preextraction radiographs and clinical charts were examined to ascertain the primary reason related to the extraction and to compile a profile for each case. In cases in which endodontic failure was the primary reason for extraction, radiographs and clinical findings were evaluated by 2experienced endodontists to assess potential treatment options. RESULTS: Between 2004 and 2019, 29.3% (1564 of 5229) of teeth replaced by dental implants at UNC School of Dentistry had undergone root canal treatment, with the mandibular first molar being the most commonly replaced tooth. The leading reasons for extraction were recurrent caries associated with defective restoration (26.6%), fracture of coronal structure (21.5%), vertical root fracture (20.9%), compromised periodontal condition (13.8%), and endodontic failure (2.4%). Two experienced endodontists evaluated extractions due to endodontic failure and concluded that 61.7% of them could have been candidates for endodontic retreatment. CONCLUSION: Substantial loss of tooth structure was the leading cause of extraction of root canal-treated teeth, followed by vertical root fracture and periodontal disease. Although endodontic failure constituted a minor portion of the reasons for extraction, a considerable number of teeth were extracted due to vertical root fractures following root canal treatment. A significant proportion of the extracted teeth due to endodontic failure could have been considered as potential candidates for endodontic retreatment.


Assuntos
Cárie Dentária , Implantes Dentários , Doenças Periodontais , Dente não Vital , Humanos , Dente não Vital/diagnóstico por imagem , Estudos Retrospectivos , Tratamento do Canal Radicular/efeitos adversos
9.
ACS Appl Mater Interfaces ; 16(1): 643-654, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38147638

RESUMO

Among the various existing layered compounds, silicon diselenide (SiSe2) possesses diverse chemical and physical properties, owing to its large interlayer spacing and interesting atomic arrangements. Despite the unique properties of layered SiSe2, it has not yet been used in energy applications. Herein, we introduce the synthesis of layered SiSe2 through a facile solid-state synthetic route and demonstrate its versatility as a sulfide solid electrolyte (SE) additive for all-solid-state batteries (ASSBs) and as an anode material for Li-ion batteries (LIBs). Li-argyrodites with various compositions substituted with SiSe2 are synthesized and evaluated as sulfide SEs for ASSBs. SiSe2-substituted Li-argyrodites exhibit high ionic conductivities, low activation energies, and high air stabilities. In addition, when using a sulfide SE, the ASSB full cell exhibits a high discharge/charge capacity of 202/169 mAh g-1 with a high initial Coulombic efficiency (ICE) of 83.7% and stable capacity retention at 1C after 100 cycles. Furthermore, the Li-storage properties of SiSe2 as an anode material for LIBs are evaluated, and its Li-pathway mechanism is explored by using various cutting-edge ex situ analytical tools. Moreover, the SiSe2 nanocomposite anode exhibits a high Li- insertion/extraction capacity of 950/775 mAh g-1, a high ICE of 81.6%, a fast rate capability, and stable capacity retention after 300 cycles. Accordingly, layered SiSe2 and its versatile applications as a sulfide SE additive for ASSBs and an anode material for LIBs are promising candidates in energy storage applications as well as myriad other applications.

10.
Sci Adv ; 9(39): eadi8918, 2023 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-37756405

RESUMO

Numerous wireless optogenetic systems have been reported for practical tether-free optogenetics in freely moving animals. However, most devices rely on battery-powered or coil-powered systems requiring periodic battery replacement or bulky, high-cost charging equipment with delicate antenna design. This leads to spatiotemporal constraints, such as limited experimental duration due to battery life or animals' restricted movement within specific areas to maintain wireless power transmission. In this study, we present a wireless, solar-powered, flexible optoelectronic device for neuromodulation of the complete freely behaving subject. This device provides chronic operation without battery replacement or other external settings including impedance matching technique and radio frequency generators. Our device uses high-efficiency, thin InGaP/GaAs tandem flexible photovoltaics to harvest energy from various light sources, which powers Bluetooth system to facilitate long-term, on-demand use. Observation of sustained locomotion behaviors for a month in mice via secondary motor cortex area stimulation demonstrates the notable capabilities of our device, highlighting its potential for space-free neuromodulating applications.


Assuntos
Optogenética , Tecnologia sem Fio , Camundongos , Animais , Optogenética/métodos , Movimento , Fontes de Energia Elétrica
11.
Int J Biol Macromol ; 244: 124982, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37244326

RESUMO

Transition metal dichalcogenides (TMDs) have gained considerable attention for a broad range of applications, including cancer therapy. Production of TMD nanosheets using liquid exfoliation provides an inexpensive and facile route to achieve high yields. In this study, we developed TMD nanosheets using gum arabic as an exfoliating and stabilizing agent. Different types of TMDs, including MoS2, WS2, MoSe2, and WSe2 nanosheets, were produced using gum arabic and were characterized physicochemically. The developed gum arabic TMD nanosheets exhibited a remarkable photothermal absorption capacity in the near-infrared (NIR) region (808 nm and 1 W⋅cm-2). The drug doxorubicin was loaded on the gum arabic-MoSe2 nanosheets (Dox-G-MoSe2), and the anticancer activity was evaluated using MDA-MB-231 cells and a water-soluble tetrazolium salt (WST-1) assay, live and dead cell assays, and flow cytometry. Dox-G-MoSe2 significantly inhibited MDA-MB-231 cancer cell proliferation under the illumination of an NIR laser at 808 nm. These results indicate that Dox-G-MoSe2 is a potentially valuable biomaterial for breast cancer therapy.


Assuntos
Neoplasias da Mama , Compostos Organosselênicos , Humanos , Feminino , Goma Arábica , Molibdênio/química , Morfolinas , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/farmacologia , Doxorrubicina/química
12.
Environ Sci Pollut Res Int ; 30(16): 48157-48167, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36750517

RESUMO

Ex situ mineralization of CO2 is a promising technology that employs Ca- and Mg-rich industrial wastes but it simultaneously produces end products. Although Mg is a major mineralization source, it can adversely impact carbonate precipitation and crystal stability during co-precipitation in combination with Ca2+. In this study, the effects of Mg2+ ions on the mineralization process and its products were investigated using precipitates formed at different aqueous concentrations of Mg2+. The final phases of the precipitates were quantitatively evaluated at the end of each process. The alterations undergone by the calcite crystals, which constituted the dominant carbonate phase in each experiment, were analyzed using a sophisticated crystallographic approach. Aragonite was detected at high Mg2+ concentrations (Mg2+/Ca2+ ratio of 2.00), although brucite was the sole phase of the Mg crystal. The increase in Mg2+ ion concentration induced the formation of an amorphous solid. The results revealed that a drastic transformation of the calcite lattice occurred when the ratio of Mg2+/Ca2+ exceeded 1.00, agreeing with the shifts observed in the calcite structure upon comparing the precipitates formed at the Mg2+/Ca2+ ratios of 1.00 and 2.00, wherein microstrain and crystallite sizes changed from 0.040 and 55.33 nm to 0.1533 and 12.35 nm, respectively. At a Mg2+/Ca2+ ratio of 2.00, 6.51% of the Ca2+ ions in the calcite structure were substituted by Mg2+, increasing the surface energy of the crystal and the solubility of the carbonate. Therefore, Mg2+ is a potential hindrance that can impede the precipitation of carbonates and increase instability at certain concentrations.


Assuntos
Carbono , Magnésio , Magnésio/química , Carbonato de Cálcio/química , Carbonatos , Água/química
13.
Sci Adv ; 9(5): eadf5883, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36724224

RESUMO

Recent advances in passive radiative cooling systems describe a variety of strategies to enhance cooling efficiency, while the integration of such technology with a bioinspired design using biodegradable materials can offer a research opportunity to generate energy in a sustainable manner, favorable for the temperature/climate system of the planet. Here, we introduce stretchable and ecoresorbable radiative cooling/heating systems engineered with zebra stripe-like patterns that enable the generation of a large in-plane temperature gradient for thermoelectric generation. A comprehensive study of materials with theoretical evaluations validates the ability to accomplish the target performances even under external mechanical strains, while all systems eventually disappear under physiological conditions. Use of the zebra print for selective radiative heating demonstrates an unexpected level of temperature difference compared to use of radiative cooling emitters alone, which enables producing energy through resorbable silicon-based thermoelectric devices. The overall result suggests the potential of scalable, ecofriendly renewable energy systems.

14.
iScience ; 26(1): 105780, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36590160

RESUMO

The increasing advances in thermal radiation regulators have attracted growing interest, particularly in infrared sources, thermal management, and camouflage. Despite many advances in dynamic thermal emitters with great controllability, sustained external energy is required to maintain the desired emission. In this study, we present a polarization-driven thermal emission regulator based on a two-way control: i) phase change and ii) polarization tuning. Based on a conventional, non-volatile phase change material, i.e., Ge2Sb2Te5 (GST), we newly introduce an anisotropic medium for facile emissivity regulation without heat energy consumption. A rigorous coupled-wave analysis method provides design guidelines for finding optimal structural parameters. We utilized a simple glancing angle deposition process which induces tilted self-aligned nanocolumns with anisotropic properties. The fabricated sample shows polarization-sensitive thermal regulation through thermal imaging spectroscopic measurement. Additionally, we manufactured a multispectral visibly/thermally camouflaged patch that identifies encrypted information at a specific polarization state for a proof-of-concept demonstration.

15.
Polymers (Basel) ; 14(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36145966

RESUMO

Dielectric elastomer actuators (DEAs), a type of electroactive polymers (EAPs), are smart materials that are used in various fields such as artificial muscles and biomimetic robots. In this study, graphene nanoplatelets (GNPs), which are conductive carbon fillers, were added to a widely used DEA, namely, polydimethylsiloxane (PDMS), to improve its low actuated strain. Four grades of GNPs were used: H5, H25, M5, and M25 (here, the number following the letter indicates the average particle size of the GNPs in µm). The average layer thickness of the H grade is 13−14 nm and that of the M grade is 5−7 nm. PDMS composites were prepared by adding 0.5, 1, 2, and 3 wt% of each GNP, following which the mechanical properties, dielectric properties, and actuated strain of the composites were measured. The mechanical properties were found to increase as the particle size increased. Regarding the dielectric characteristics, it was found that the higher the aspect ratio of the filler, the easier the formation of a micro-capacitor network in the composite­this led to an increase in the dielectric constant. In addition, the higher amounts of GNPs in the composites also led to an increase in the dielectric constant. For the actuated strain analysis, the electromechanical sensitivity was calculated using the ratio of the dielectric constant to the Young's modulus, which is proportional to the strain. However, it was found that when the loss tangent was high, the performance of the actuated strain decreased owing to the conversion of electric energy into thermal energy and leakage current loss. As a result, the highest actuated strain was exhibited by the M25 composite, with an actuated strain value of 3.01% measured at a low electric field (<4 kV/mm). In conclusion, we proved that the GNP−PDMS composites with a thin layer and large particle size exhibited high deformation.

16.
Structure ; 30(11): 1530-1537.e3, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36087575

RESUMO

The heterodimer of human ubiquitin fusion degradation 1 (hUfd1) and human nuclear protein localization 4 (hNpl4) is a major cofactor of human p97 adenosine triphosphatase (ATPase). The p97-Ufd1-Npl4 complex translocates the ubiquitin-conjugated proteins from the endoplasmic reticulum membrane to the cytoplasm. Ubiquitinated proteins are then degraded by the proteasome. The structures of Npl4 and Ufd1-Npl4 (UN) complex in Saccharomyces cerevisiae have been recently reported; however, the structures of hNpl4 and the human UN complex remain unknown. Here, we report the crystal structures of the human UN complex at a resolution of 2.7 Å and hNpl4 at a resolution of 3.0 Å. We also present atomic details and characterization of the human UN complex. Crystallographic studies and site-directed mutagenesis of the hUfd1 residues involved in the interaction with hNpl4 revealed the atomic details of the two proteins.


Assuntos
Adenosina Trifosfatases , Proteínas de Saccharomyces cerevisiae , Humanos , Ligação Proteica , Adenosina Trifosfatases/química , Proteínas Nucleares/metabolismo , Ubiquitina/metabolismo , Retículo Endoplasmático/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteína com Valosina/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
17.
Cell Chem Biol ; 29(10): 1532-1540.e5, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36167077

RESUMO

Dimerization of beta 2-adrenergic receptor (ß2-AR) has been observed across various physiologies. However, the function of dimeric ß2-AR is still elusive. Here, we revealed that dimerization of ß2-AR is responsible for the constitutive activity of ß2-AR generating inverse agonism. Using a co-immunoimmobilization assay, we found that transient ß2-AR dimers exist in a resting state, and the dimer was disrupted by the inverse agonists. A Gαs preferentially interacts with dimeric ß2-AR, but not monomeric ß2-AR, in a resting state, resulting in the production of a resting cAMP level. The formation of ß2-AR dimers requires cholesterol on the plasma membrane. The cholesterol did not interfere with the agonist-induced activation of monomeric ß2-AR, unlike the inverse agonists, implying that the cholesterol is a specific factor regulating the dimerization of ß2-AR. Our model not only shows the function of dimeric ß2-AR but also provides a molecular insight into the mechanism of the inverse agonism of ß2-AR.


Assuntos
Transdução de Sinais , Dimerização , Membrana Celular/metabolismo
18.
J Inflamm Res ; 15: 2665-2693, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35509323

RESUMO

Incense burning is practiced alongside many sacred rituals across different regions of the world. Invariable constituents of incense brands are 21% (by weight) herbal and wood powder, 33% bamboo stick, 35% fragrance material, and 11% adhesive powder. Major incense-combustion outputs include particulate matter (PM), volatile organic content, and polyaromatic hydrocarbons. The relative toxicity of these products is an implicit function of particle size and incomplete combustion, which in turn vary for a specific incense brand. Lately, the attention given to the Air Quality Index by international regulatory bodies has created concern about mounting PM toxicity. The uncharacteristically small physical dimensions of these entities complicates their detection, and with no effect of gravity PM fractions rapidly contribute to oxidative stress, enhancing random biochemical reactions upon being inhaled. Incense burning generates four times the PM extent (45 mg•g-1) of cigarettes (~10 mg•g-1). Several poisonous gases, such as CO, CO2, NO2, and SO2, and the unavoidable challenge of disposing of the burnt incense ash further add to the toxicity. Taken together, these issues demonstrate that incense burning warrants prompt attention. The aim of this article is to highlight the toxicity of incense-combustion materials on the environment and human health. This discussion could be significant in framing future policy regarding ecofriendly incense manufacture and reduced usage.

19.
Materials (Basel) ; 15(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35160893

RESUMO

Lignin is an important commercially produced polymeric material. It is used extensively in both industrial and agricultural activities. Recently, it has drawn much attention from the scientific community. It is abundantly present in nature and has significant application in the production of biodegradable materials. Its wide usage includes drug delivery, polymers and several forms of emerging lignin nanoparticles. The synthesis of lignin nanoparticles is carried out in a controlled manner. The traditional manufacturing techniques are costly and often toxic and hazardous to the environment. This review article highlights simple, safe, climate-friendly and ecological approaches to the synthesis of lignin nanoparticles. The changeable, complex structure and recalcitrant nature of lignin makes it challenging to degrade. Researchers have discovered a small number of microorganisms that have developed enzymatic and non-enzymatic metabolic pathways to use lignin as a carbon source. These microbes show promising potential for the biodegradation of lignin. The degradation pathways of these microbes are also described, which makes the study of biological synthesis much easier. However, surface modification of lignin nanoparticles is something that is yet to be explored. This review elucidates the recent advances in the biodegradation of lignin in the ecological system. It includes the current approaches, methods for modification, new applications and research for the synthesis of lignin and lignin nanoparticles. Additionally, the intricacy of lignin's structure, along with its chemical nature, is well-described. This article will help increase the understanding of the utilization of lignin as an economical and alternative-resource material. It will also aid in the minimization of solid waste arising from lignin.

20.
Opt Express ; 29(20): 31364-31375, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34615230

RESUMO

For the efficient radiative cooling of objects, coolers should emit heat within atmospheric transparent window and block heat absorption from the surrounding environments. Thus, selective emitters enable highly efficient cooling via engineered photonic structures such as metamaterials and multi-stacking structures. However, these structures require sophisticated fabrication processes and large quantities of materials, which can restrict mass-production. This study introduces an ultra-thin (∼1 µm) and near-unity selective emitter (UNSE) within the atmospheric window, which can be fabricated using simple and affordable process. The combination of infrared (IR) lossy layers and high index lossless layer enhances the resonance in the structure thus, the emissivity in long wavelength IR region increases to near-unity within a thickness of ∼1 µm.

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