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1.
Chem Sci ; 15(26): 9915-9926, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38966366

ABSTRACT

Chemodynamic therapy (CDT) is a potential cancer treatment strategy, which relies on Fenton chemistry to transform hydrogen peroxide (H2O2) into highly cytotoxic reactive oxygen species (ROS) for tumor growth suppression. Although overproduced H2O2 in cancerous tissues makes CDT a feasible and specific tumor therapeutic modality, the treatment outcomes of traditional chemodynamic agents still fall short of expectations. Reprogramming cellular metabolism is one of the hallmarks of tumors, which not only supports unrestricted proliferative demands in cancer cells, but also mediates the resistance of tumor cells against many antitumor modalities. Recent discoveries have revealed that various cellular metabolites including H2O2, iron, lactate, glutathione, and lipids have distinct effects on CDT efficiency. In this perspective, we intend to provide a comprehensive summary of how different endogenous molecules impact Fenton chemistry for a deep understanding of mechanisms underlying endogenous regulation-enhanced CDT. Moreover, we point out the current challenges and offer our outlook on the future research directions in this field. We anticipate that exploring CDT through manipulating metabolism will yield significant advancements in tumor treatment.

2.
Adv Mater ; : e2406235, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39007254

ABSTRACT

The great challenges for existing wearable pressure sensors are the degradation of sensing performance and weak interfacial adhesion owing to the low mechanical transfer efficiency and interfacial differences at the skin-sensor interface. Here, an ultrasensitive wearable pressure sensor is reported by introducing a stress-concentrated tip-array design and self-adhesive interface for improving the detection limit. A bipyramidal microstructure with various Young's moduli is designed to improve mechanical transfer efficiency from 72.6% to 98.4%. By increasing the difference in modulus, it also mechanically amplifies the sensitivity to 8.5 V kPa-1 with a detection limit of 0.14 Pa. The self-adhesive hydrogel is developed to strengthen the sensor-skin interface, which allows stable signals for long-term and real-time monitoring. It enables generating high signal-to-noise ratios and multifeatures when wirelessly monitoring weak pulse signals and eye muscle movements. Finally, combined with a deep learning bimodal fused network, the accuracy of fatigued driving identification is significantly increased to 95.6%.

3.
ACS Nano ; 18(26): 17041-17052, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38904995

ABSTRACT

Flexible tactile sensors show promise for artificial intelligence applications due to their biological adaptability and rapid signal perception. Triboelectric sensors enable active dynamic tactile sensing, while integrating static pressure sensing and real-time multichannel signal transmission is key for further development. Here, we propose an integrated structure combining a capacitive sensor for static spatiotemporal mapping and a triboelectric sensor for dynamic tactile recognition. A liquid metal-based flexible dual-mode triboelectric-capacitive-coupled tactile sensor (TCTS) array of 4 × 4 pixels achieves a spatial resolution of 7 mm, exhibiting a pressure detection limit of 0.8 Pa and a fast response of 6 ms. Furthermore, neuromorphic computing using the MXene-based synaptic transistor achieves 100% recognition accuracy of handwritten numbers/letters within 90 epochs based on dynamic triboelectric signals collected by the TCTS array, and cross-spatial information communication from the perceived multichannel tactile data is realized in the mixed reality space. The results illuminate considerable application possibilities of dual-mode tactile sensing technology in human-machine interfaces and advanced robotics.

4.
Angew Chem Int Ed Engl ; 63(10): e202318155, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38109458

ABSTRACT

Real-time monitoring of hydroxyl radical (⋅OH) generation is crucial for both the efficacy and safety of chemodynamic therapy (CDT). Although ⋅OH probe-integrated CDT agents can track ⋅OH production by themselves, they often require complicated synthetic procedures and suffer from self-consumption of ⋅OH. Here, we report the facile fabrication of a self-monitored chemodynamic agent (denoted as Fc-CD-AuNCs) by incorporating ferrocene (Fc) into ß-cyclodextrin (CD)-functionalized gold nanoclusters (AuNCs) via host-guest molecular recognition. The water-soluble CD served not only as a capping agent to protect AuNCs but also as a macrocyclic host to encapsulate and solubilize hydrophobic Fc guest with high Fenton reactivity for in vivo CDT applications. Importantly, the encapsulated Fc inside CD possessed strong electron-donating ability to effectively quench the second near-infrared (NIR-II) fluorescence of AuNCs through photoinduced electron transfer. After internalization of Fc-CD-AuNCs by cancer cells, Fenton reaction between redox-active Fc quencher and endogenous hydrogen peroxide (H2 O2 ) caused Fc oxidation and subsequent NIR-II fluorescence recovery, which was accompanied by the formation of cytotoxic ⋅OH and therefore allowed Fc-CD-AuNCs to in situ self-report ⋅OH generation without undesired ⋅OH consumption. Such a NIR-II fluorescence-monitored CDT enabled the use of renal-clearable Fc-CD-AuNCs for efficient tumor growth inhibition with minimal side effects in vivo.


Subject(s)
Ferrous Compounds , Nanoparticles , Neoplasms , Humans , Nanomedicine , Metallocenes , Fluorescence , Oxidation-Reduction , Cell Line, Tumor , Hydrogen Peroxide/chemistry , Nanoparticles/chemistry , Tumor Microenvironment
5.
Cell Host Microbe ; 31(11): 1882-1897.e10, 2023 11 08.
Article in English | MEDLINE | ID: mdl-37848029

ABSTRACT

Epstein-Barr virus (EBV) is a global public health concern, as it is known to cause multiple diseases while also being etiologically associated with a wide range of epithelial and lymphoid malignancies. Currently, there is no available prophylactic vaccine against EBV. gB is the EBV fusion protein that mediates viral membrane fusion and participates in host recognition, making it critical for EBV infection in both B cells and epithelial cells. Here, we present a gB nanoparticle, gB-I53-50 NP, that displays multiple copies of gB. Compared with the gB trimer, gB-I53-50 NP shows improved structural integrity and stability, as well as enhanced immunogenicity in mice and non-human primate (NHP) preclinical models. Immunization and passive transfer demonstrate a robust and durable protective antibody response that protects humanized mice against lethal EBV challenge. This vaccine candidate demonstrates significant potential in preventing EBV infection, providing a possible platform for developing prophylactic vaccines for EBV.


Subject(s)
Epstein-Barr Virus Infections , Vaccines , Cricetinae , Animals , Mice , Herpesvirus 4, Human , Epstein-Barr Virus Infections/prevention & control , Antibody Formation , CHO Cells , Antibodies, Neutralizing , Antibodies, Viral
6.
Sci Immunol ; 8(87): eabq2424, 2023 09 29.
Article in English | MEDLINE | ID: mdl-37738362

ABSTRACT

Metabolic fitness of T cells is essential for their vitality, which is largely dependent on the behavior of the mitochondria. The nature of mitochondrial behavior in tumor-infiltrating T cells remains poorly understood. In this study, we show that mitofusin-2 (MFN2) expression is positively correlated with the prognosis of multiple cancers. Genetic ablation of Mfn2 in CD8+ T cells dampens mitochondrial metabolism and function and promotes tumor progression. In tumor-infiltrating CD8+ T cells, MFN2 enhances mitochondria-endoplasmic reticulum (ER) contact by interacting with ER-embedded Ca2+-ATPase SERCA2, facilitating the mitochondrial Ca2+ influx required for efficient mitochondrial metabolism. MFN2 stimulates the ER Ca2+ retrieval activity of SERCA2, thereby preventing excessive mitochondrial Ca2+ accumulation and apoptosis. Elevating mitochondria-ER contact by increasing MFN2 in CD8+ T cells improves the efficacy of cancer immunotherapy. Thus, we reveal a tethering-and-buffering mechanism of organelle cross-talk that regulates the metabolic fitness of tumor-infiltrating CD8+ T cells and highlights the therapeutic potential of enhancing MFN2 expression to optimize T cell function.


Subject(s)
CD8-Positive T-Lymphocytes , Neoplasms , Humans , Apoptosis , Endoplasmic Reticulum , GTP Phosphohydrolases , Mitochondria , Mitochondrial Proteins
7.
J Biosci Bioeng ; 136(4): 270-277, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37544800

ABSTRACT

The yeast Saccharomyces cerevisiae able to tolerate lignocellulose-derived inhibitors like furfural. Yeast strain performance tolerance has been measured by the length of the lag phase for cell growth in response to the furfural inhibitor challenge. The aims of this work were to obtain RDS1 yeast tolerant strain against furfural through overexpression using a method of in vivo homologous recombination. Here, we report that the overexpressing RDS1 recovered more rapidly and displayed a lag phase at about 12 h than its parental strain. Overexpressing RDS1 strain encodes a novel aldehyde reductase with catalytic function for reduction of furfural with NAD(P)H as the co-factor. It displayed the highest specific activity (24.8 U/mg) for furfural reduction using NADH as a cofactor. Fluorescence microscopy revealed improved accumulation of reactive oxygen species resistance to the damaging effects of inhibitor in contrast to the parental. Comparative transcriptomics revealed key genes potentially associated with stress responses to the furfural inhibitor, including specific and multiple functions involving defensive reduction-oxidation reaction process and cell wall response. A significant change in expression level of log2 (fold change >1) was displayed for RDS1 gene in the recombinant strain, which demonstrated that the introduction of RDS1 overexpression promoted the expression level. Such signature expressions differentiated tolerance phenotypes of RDS1 from the innate stress response of its parental strain. Overexpression of the RDS1 gene involving diversified functional categories is accountable for stress tolerance in yeast S. cerevisiae to survive and adapt the furfural during the lag phase.


Subject(s)
Furaldehyde , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae , Furaldehyde/pharmacology , NAD/metabolism , Phenotype , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/metabolism , Transcriptome
8.
Eur J Cancer ; 191: 112965, 2023 09.
Article in English | MEDLINE | ID: mdl-37540921

ABSTRACT

PURPOSE: The safety and objective clinical responses were observed in the phase I study using adjuvant autologous tumour-infiltrating lymphocytes (TILs) following concurrent chemoradiotherapy (CCRT) in nasopharyngeal carcinoma (NPC) patients. METHODS AND MATERIALS: One hundred fifty-six patients with stage III-IVb and pretreatment Epstein-Barr virus DNA levels of ≥4000 copies/ml were randomly assigned to receive CCRT combined with TIL infusion (n = 78) or CCRT alone (n = 78). All patients received CCRT and patients assigned to the TIL group received TIL infusion within 1 week after CCRT. The primary endpoint was investigator-assessed progression-free survival (PFS) at 3 years. RESULTS: After a median follow-up of 62.3 months, no significant difference was observed in the 3-year PFS rate between the CCRT plus TIL infusion group and CCRT alone group (75.6% versus 74.4%, hazard ratios, 1.08; 95% confidence intervals, 0.62-1.89). TIL infusion was safe without grade 3 or 4 adverse events and all the high-grade adverse effects were associated with myelosuppression caused by CCRT. Exploratory analysis showed that a potential survival benefit was observed with TILs in patients with lower levels of circulating CD8+TIM3+ cells, serum IL-8 or PD-L1. The infused TIL products in patients with favourable outcomes were associated with increased transcription of interferon-γ and a series of inflammatory related genes and a lower exhausted score. CONCLUSION: The primary objective of prolonging PFS with CCRT plus TILs in high-risk NPC patients was not met. These findings may provide evidence for the design of future trials investigating the combination of TILs plus immune checkpoint inhibitors based on CCRT in high-risk NPC patients. TRIAL REGISTRATION NUMBER: NCT02421640.


Subject(s)
Epstein-Barr Virus Infections , Nasopharyngeal Neoplasms , Humans , Adjuvants, Immunologic , Chemoradiotherapy/methods , Disease-Free Survival , DNA , Epstein-Barr Virus Infections/complications , Herpesvirus 4, Human , Lymphocytes, Tumor-Infiltrating , Nasopharyngeal Carcinoma/therapy , Nasopharyngeal Neoplasms/pathology
9.
Appl Environ Microbiol ; 89(6): e0050023, 2023 06 28.
Article in English | MEDLINE | ID: mdl-37272792

ABSTRACT

Microbial assembly and metabolic potential in the subsurface critical zone (SCZ) are substantially impacted by subsurface geochemistry and hydrogeology, selecting for microbes distinct from those in surficial soils. In this study, we integrated metagenomics and geochemistry to elucidate how microbial composition and metabolic potential are shaped and impacted by vertical variations in geochemistry and hydrogeology in terrestrial subsurface sediment. A sediment core from an uncontaminated, pristine well at Oak Ridge Field Research Center in Oak Ridge, Tennessee, including the shallow subsurface, vadose zone, capillary fringe, and saturated zone, was used in this study. Our results showed that subsurface microbes were highly localized and that communities were rarely interconnected. Microbial community composition as well as metabolic potential in carbon and nitrogen cycling varied even over short vertical distances. Further analyses indicated a strong depth-related covariation of community composition with a subset of 12 environmental variables. An analysis of dissolved organic carbon (DOC) quality via ultrahigh resolution mass spectrometry suggested that the SCZ was generally a low-carbon environment, with the relative portion of labile DOC decreasing and that of recalcitrant DOC increasing along the depth, selecting microbes from copiotrophs to oligotrophs and also impacting the microbial metabolic potential in the carbon cycle. Our study demonstrates that sediment geochemistry and hydrogeology are vital in the selection of distinct microbial populations and metabolism in the SCZ. IMPORTANCE In this study, we explored the links between geochemical parameters, microbial community structure and metabolic potential across the depth of sediment, including the shallow subsurface, vadose zone, capillary fringe, and saturated zone. Our results revealed that microbes in the terrestrial subsurface can be highly localized, with communities rarely being interconnected along the depth. Overall, our research demonstrates that sediment geochemistry and hydrogeology are vital in the selection of distinct microbial populations and metabolic potential in different depths of subsurface terrestrial sediment. Such studies correlating microbial community analyses and geochemistry analyses, including high resolution mass spectrometry analyses of natural organic carbon, will further the fundamental understanding of microbial ecology and biogeochemistry in subsurface terrestrial ecosystems and will benefit the future development of predictive models on nutrient turnover in these environments.


Subject(s)
Bacteria , Microbiota , Bacteria/metabolism , Carbon/metabolism , Tennessee
10.
Pol J Microbiol ; 72(2): 177-186, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-37314359

ABSTRACT

Lignocellulosic biomass is still considered a feasible source of bioethanol production. Saccharomyces cerevisiae can adapt to detoxify lignocellulose-derived inhibitors, including furfural. Tolerance of strain performance has been measured by the extent of the lag phase for cell proliferation following the furfural inhibitor challenge. The purpose of this work was to obtain a tolerant yeast strain against furfural through overexpression of YPR015C using the in vivo homologous recombination method. The physiological observation of the overexpressing yeast strain showed that it was more resistant to furfural than its parental strain. Fluorescence microscopy revealed improved enzyme reductase activity and accumulation of oxygen reactive species due to the harmful effects of furfural inhibitor in contrast to its parental strain. Comparative transcriptomic analysis revealed 79 genes potentially involved in amino acid biosynthesis, oxidative stress, cell wall response, heat shock protein, and mitochondrial-associated protein for the YPR015C overexpressing strain associated with stress responses to furfural at the late stage of lag phase growth. Both up- and down-regulated genes involved in diversified functional categories were accountable for tolerance in yeast to survive and adapt to the furfural stress in a time course study during the lag phase growth. This study enlarges our perceptions comprehensively about the physiological and molecular mechanisms implicated in the YPR015C overexpressing strain's tolerance under furfural stress. Construction illustration of the recombinant plasmid. a) pUG6-TEF1p-YPR015C, b) integration diagram of the recombinant plasmid pUG6-TEF1p-YPR into the chromosomal DNA of Saccharomyces cerevisiae.


Subject(s)
Furaldehyde , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genetics , Furaldehyde/pharmacology , Biomass , Cell Wall , Gene Expression Profiling
11.
Nanomicro Lett ; 15(1): 109, 2023 Apr 18.
Article in English | MEDLINE | ID: mdl-37071340

ABSTRACT

Realizing real-time monitoring of physiological signals is vital for preventing and treating chronic diseases in elderly individuals. However, wearable sensors with low power consumption and high sensitivity to both weak physiological signals and large mechanical stimuli remain challenges. Here, a flexible triboelectric patch (FTEP) based on porous-reinforcement microstructures for remote health monitoring has been reported. The porous-reinforcement microstructure is constructed by the self-assembly of silicone rubber adhering to the porous framework of the PU sponge. The mechanical properties of the FTEP can be regulated by the concentrations of silicone rubber dilution. For pressure sensing, its sensitivity can be effectively improved fivefold compared to the device with a solid dielectric layer, reaching 5.93 kPa-1 under a pressure range of 0-5 kPa. In addition, the FTEP has a wide detection range up to 50 kPa with a sensitivity of 0.21 kPa-1. The porous microstructure makes the FTEP ultra-sensitive to external pressure, and the reinforcements endow the device with a greater deformation limit in a wide detection range. Finally, a novel concept of the wearable Internet of Healthcare (IoH) system for real-time physiological signal monitoring has been proposed, which could provide real-time physiological information for ambulatory personalized healthcare monitoring.

12.
Angew Chem Int Ed Engl ; 62(22): e202302255, 2023 05 22.
Article in English | MEDLINE | ID: mdl-36959091

ABSTRACT

Ferrous iron (Fe2+ ) has more potent hydroxyl radical (⋅OH)-generating ability than other Fenton-type metal ions, making Fe-based nanomaterials attractive for chemodynamic therapy (CDT). However, because Fe2+ can be converted by ferritin heavy chain (FHC) to nontoxic ferric form and then sequestered in ferritin, therapeutic outcomes of Fe-mediated CDT agents are still far from satisfactory. Here we report the synthesis of siRNA-embedded Fe0 nanoparticles (Fe0 -siRNA NPs) for self-reinforcing CDT via FHC downregulation. Upon internalization by cancer cells, pH-responsive Fe0 -siRNA NPs are degraded to release Fe2+ and FHC siRNA in acidic endo/lysosomes with the aid of oxygen (O2 ). The accompanied O2 depletion causes an intracellular pH decrease, which further promotes the degradation of Fe0 -siRNA NPs. In addition to initiating chemodynamic process, Fe2+ -catalyzed ⋅OH generation facilitates endo/lysosomal escape of siRNA by disrupting the membranes, enabling FHC downregulation-enhanced CDT.


Subject(s)
Nanoparticles , Neoplasms , Humans , Iron/metabolism , Apoferritins/metabolism , Apoferritins/therapeutic use , RNA, Small Interfering/therapeutic use , Down-Regulation , Hydroxyl Radical/metabolism , Nanoparticles/therapeutic use , Cell Line, Tumor , Neoplasms/drug therapy , Hydrogen Peroxide/metabolism
13.
J Surg Res ; 282: 84-92, 2023 02.
Article in English | MEDLINE | ID: mdl-36257167

ABSTRACT

INTRODUCTION: Levels of extracellular histones are highly increased in sepsis and may facilitate microcirculatory dysfunction. Unfractionated heparin (UFH) binds histones and neutralizes their cytotoxicity. We investigated the effect of UFH on microcirculatory dysfunction by interacting with extracellular histones in endotoxemic rats. METHODS: Twenty-four Wistar rats were randomly divided into three groups: control, lipopolysaccharide (LPS) group, and LPS + UFH group. In the LPS and LPS + UFH groups, 10 mg/kg LPS was injected to induce endotoxemia, and 100 IU/kg/h UFH was administered intravenously in the LPS + UFH group. The rats underwent midline laparotomy, and then intestinal microcirculation was evaluated using an incident dark field microscope. Circulating histones and microstructures of the rat intestinal microvascular endothelium were also detected. Additionally, the antagonistic effect of UFH on histone-induced cytotoxicity was investigated in human intestinal microvascular endothelial cells. RESULTS: UFH protected the microcirculation of the intestinal serosa and mucosa in endotoxemic rats, as evidenced by increased total vessel density, perfused vessel density, and proportion of perfused vessels of both the serosa and mucosa, and increased microcirculatory flow index of the mucosa in the LPS + UFH group. UFH treatment decreased the levels of circulating histones and alleviated intestinal microvascular endothelial injuries in endotoxemic rats. Furthermore, UFH inhibited histone cytotoxicity in vitro. CONCLUSIONS: UFH attenuated microcirculatory dysfunction in endotoxemic rats by antagonizing extracellular histones, thereby providing a potential therapeutic strategy for sepsis.


Subject(s)
Endotoxemia , Sepsis , Rats , Humans , Animals , Heparin/pharmacology , Heparin/therapeutic use , Endotoxemia/metabolism , Microcirculation , Histones , Lipopolysaccharides/pharmacology , Endothelial Cells , Rats, Wistar , Sepsis/drug therapy
14.
Front Microbiol ; 13: 1052525, 2022.
Article in English | MEDLINE | ID: mdl-36560953

ABSTRACT

The oral microbiome, associated with both oral disease and systemic disease, is in dynamic status along the whole life, and many factors including maternal microbiomes could impact the oral microbiome. While fewer studies have been conducted to study the characteristics of the oral microbiome in neonates and the associated maternal factors. Hence, we collected the microbiome of 15 mother-infant pairs across multiple body sites from birth up to 4 days postpartum and used high-throughput sequencing to characterize the microbiomes in mothers and their neonates. The oral microbiome in the neonates changed obviously during the 4 days after birth. Many bacteria originating from the vagina, skin, and environment disappeared in oral cavity over time, such as Prevotella bivia and Prevotella jejuni. Meanwhile, Staphylococcus epidermidis RP62A phage SP-beta, predominate bacterium in maternal skin microbiome and Streptococcus unclassified, main bacterium in vaginal microbiome, obviously increased in neonatal oral microbiome as time went on. Interestingly, as time progressed, the composition of the oral microbiome in the neonates was more similar to that of the milk microbiome in their mothers. Moreover, we found that the changes in the predominant bacteria in the neonates were in line with those in the neonates exposed to the environment. Together, these data described the sharp dynamics of the oral microbiome in neonates and the importance of maternal efforts in the development of the neonatal microbiome.

15.
BMC Oral Health ; 22(1): 649, 2022 12 28.
Article in English | MEDLINE | ID: mdl-36577985

ABSTRACT

BACKGROUND: The ex vivo study is to compare the root canal preparation outcomes achieved by five nickel-titanium single-file instrumentation systems (M3-L, Reciproc Blue, V-Taper 2H, WaveOne Gold, XP-endo Shaper) in severely curved molar root canals. METHODS: A total of 60 root canals were selected from extracted human molar teeth with curvatures ranging from 25° to 50° and divided into five groups based on the instrumentation system employed (n = 12). Before and after root canal preparation, a Micro-CT scan was taken, and pre- and post-operative data were analyzed to evaluate the following parameters: volume increment of root canals (VI), untouched root canal areas (UTA), and canal transportation (CT). Apically extruded debris (AD) was collected during preparation. After that, all samples were separated into two parts and examined respectively by scanning electron microscope (SEM) to assess cleaning ability. Data were statistically analyzed with ANOVA (UTA, AD, VI) or Kruskal-Wallis test (CT, SEM-score), the level of significance was set at α = 0.05. RESULTS: There were no significant differences between the five systems regarding the AD, VI, and UTA parameters (P > 0.05). In terms of CT, no significant difference was noted at the straight section of canal and apical levels, while XP-endo Shaper showed less canal transportation than M3-L at the level of curved vertex (P < 0.05), and the centering ability of V-Taper 2H was significantly better than WaveOne Gold at the initial point of bending (P < 0.05). Debris and smear layers were present on the canal walls of all specimens, the apical thirds of the canal presented higher SEM scores than the coronal thirds in all groups (P < 0.05). Reciproc Blue and XP-endo Shaper showed fewer smear scores than WaveOne Gold in the apical thirds (P < 0.01 and P < 0.05, respectively), and no statistical difference was found between other groups in the middle and coronal thirds. CONCLUSION: The five single-file systems evaluated performed equally in apically debris extrusion, dentin removal, and untouched root canal areas, while XP-endo Shaper and V-Taper 2H resulted in less canal transportation compared to M3-L and WaveOne Gold. Regarding cleaning ability, Reciproc Blue and XP-endo Shaper were associated with less smear layer than WaveOne Gold in the apical thirds.


Subject(s)
Dental Instruments , Dental Pulp Cavity , Molar , Root Canal Preparation , Smear Layer , Humans , Dental Pulp Cavity/diagnostic imaging , Dental Pulp Cavity/surgery , Equipment Design/standards , Molar/diagnostic imaging , Molar/pathology , Molar/surgery , Root Canal Preparation/instrumentation , Root Canal Preparation/methods , Tooth Root/diagnostic imaging , X-Ray Microtomography , Dental Instruments/standards
16.
ACS Nano ; 16(4): 5292-5302, 2022 Apr 26.
Article in English | MEDLINE | ID: mdl-35298125

ABSTRACT

A raindrop solar cell can work either on rainy days to collect mechanical energy of the raindrops or on sunny days to harvest solar energy, which achieves high energy conversion efficiency in various energy environments. However, the low efficiency of raindrop energy harvesting is a dominating barrier to the raindrop solar cells in practical applications. In this work, a MoO3/top electrode-based triboelectric nanogenerator (MT-TENG) with high rain droplet energy conversion efficiency, integrated with a perovskite solar cell through shared electrodes, has been proposed. The interface electrons between the triboelectric layer and electrode can be blocked by the MoO3 layer with high permittivity and wide bandgap, and the MoO3-based TENG (M-TENG) therefore increases the surface charge density. Thus, the top electrode structure in the solid-liquid interface can greatly increase the output charge by 101.1 times in total. By adjusting the water droplet parameters of tap water to simulate the actual application scenario, the raindrop output power and mechanical energy conversion efficiency can reach 0.68 mW and 12.49%, respectively. In addition, due to the high transmittance of the MT-TENG, the perovskite solar cell can still sustain a high photovoltaic power conversion efficiency of 19.38%. By virtue of the shared electrode circuit design, the raindrop solar cell can continue to purvey electric power on rainy and sunny days, and it only takes about 175 s to charge a 2.2 µF capacitor to 5 V.

17.
ACS Appl Mater Interfaces ; 13(51): 61789-61798, 2021 Dec 29.
Article in English | MEDLINE | ID: mdl-34904819

ABSTRACT

As accurate step counting is a critical indicator for exercise evaluation in daily life, pedometers give a quantitative prediction of steps and analyze the amount of exercise to regulate the exercise plan. However, the merchandized pedometers still suffer from limited battery life and low accuracy. In this work, an integrated self-powered real-time pedometer system has been demonstrated. The highly integrated system contains a porous triboelectric nanogenerator (P-TENG), a data acquisition and processing (DAQP) module, and a mobile phone APP. The P-TENG works as a pressure sensor that generates electrical signals synchronized with users' footsteps, and combining it with the analogue front-end (AFE) circuit yields an ultrafast response time of 8 ms. Moreover, the combination of a mini press-to-spin-type electromagnetic generator (EMG) and a supercapacitor enables a self-powered and self-sustained operation of the entire pedometer system. This work implements the regulation of TENG signals by electronic circuit design and proposes a highly integrated system. The improved reliability and practicality provide more possibilities for wearable self-powered electronic devices.

18.
Nanomaterials (Basel) ; 11(10)2021 Oct 14.
Article in English | MEDLINE | ID: mdl-34685152

ABSTRACT

The components in traditional human-machine interaction (HMI) systems are relatively independent, distributed and low-integrated, and the wearing experience is poor when the system adopts wearable electronics for intelligent control. The continuous and stable operation of every part always poses challenges for energy supply. In this work, a triboelectric technology-based all-in-one self-powered HMI system for wireless remote telemetry and the control of intelligent cars is proposed. The dual-network crosslinking hydrogel was synthesized and wrapped with functional layers to fabricate a stretchable fibrous triboelectric nanogenerator (SF-TENG) and a supercapacitor (SF-SC), respectively. A self-charging power unit containing woven SF-TENGs, SF-SCs, and a power management circuit was exploited to harvest mechanical energy from the human body and provided power for the whole system. A smart glove designed with five SF-TENGs on the dorsum of five fingers acts as a gesture sensor to generate signal permutations. The signals were processed by the microcontroller and then wirelessly transmitted to the intelligent car for remote telemetry and control. This work is of paramount potential for the application of various terminal devices in self-powered HMI systems with high integration for wearable electronics.

19.
Mar Pollut Bull ; 167: 112381, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33962256

ABSTRACT

Per- and poly-fluorinated alkyl substances (PFAS) are a group of highly persistent synthetic chemicals utilized in many industrial and consumer products, and - significantly toward introduction to the marine environment - in fire-fighting foams. Recently, PFAS have been linked to adverse health effects, prompting the need to better understand transport, lability, and fate. Perfluorooctanesulfonic acid (PFOS), a manufactured PFAS and biodegradation product, partitions to marine sediments and thus can be used as a primary indicator toward regulatory efforts. The current study offers a spatial and temporal analysis of Puget Sound from cores collected adjacent Tacoma and Seattle, WA, as well as cores from central Hood Canal and Carr Inlet. Temporal fluxes reflected releases into the environment corresponding with initial production and subsequent increases in use. Biologically active layers ranged from 434 pg/g (Carr Inlet) to 824 pg/g (Hood Canal) PFOS, producing benthic community risk quotients between 0.11 and 0.17.


Subject(s)
Fluorocarbons , Water Pollutants, Chemical , Alkanesulfonic Acids , Environmental Monitoring , Fluorocarbons/analysis , Geologic Sediments , Washington , Water Pollutants, Chemical/analysis
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