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1.
Ecotoxicol Environ Saf ; 231: 113208, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35051759

RESUMO

Cadmium (Cd) is a highly toxic heavy metal in our living environment. Hematopoietic stem cells (HSC) are ancestors for all blood cells. Therefore understanding the impact of Cd on HSC is significant for public health. The aim of this study was to investigate the impact of Cd2+ on energy metabolism of HSC and its involvement in hematopoiesis. Wild-type C57BL/6 mice were treated with 10 ppm of Cd2+ via drinking water for 3 months, and thereafter glycolysis and mitochondrial (MT) oxidative phosphorylation (OXPHOS) of HSC in the bone marrow (BM) and their impact on hematopoiesis were evaluated. After Cd2+ treatment, HSC had reduced lactate dehydrogenase (LDH) activity and lactate production while having increased pyruvate dehydrogenase (PDH) activity, MT membrane potential, ATP production, oxygen (O2) consumption and reactive oxygen species (ROS), indicating that Cd2+ switched the pattern of energy metabolism from glycolysis to OXPHOS in HSC. Moreover, Cd2+ switch of HSC energy metabolism was critically dependent on Wnt5a/Cdc42/calcium (Ca2+) signaling triggered by a direct action of Cd2+ on HSC. To test the biological significance of Cd2+ impact on HSC energy metabolism, HSC were intervened for Ca2+, OXPHOS, or ROS in vitro, and thereafter the HSC were transplanted into lethally irradiated recipients to reconstitute the immune system; the transplantation assay indicated that Ca2+-dependent MT OXPHOS dominated the skewed myelopoiesis of HSC by Cd2+ exposure. Collectively, we revealed that Cd2+ exposure activated Wnt5a/Cdc42/Ca2+ signaling to reprogram the energy metabolism of HSC to drive myelopoiesis at the expense of lymphopoiesis.

2.
Anal Chem ; 94(2): 968-974, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-34935347

RESUMO

Skin interstitial fluid (ISF) is a biofluid with information-rich biomarkers for disease diagnosis and prognosis. Microneedle (MN) integration of sampling and instant biomarker readout hold great potential in health status monitoring and point-of-care testing (POCT). The present work describes an attractive MN sensor array for minimally invasive monitoring of ISF microRNA (miRNA) and Cu2+. The MN array is made of methacrylated gelatin (GelMA) and methacrylated hyaluronic acid (MeHA), and a further divisionally encapsulated miRNA and Cu2+ detection system, and is cross-linked through blue-light irradiation. The MN patch displays good mechanical properties that enable withstanding more than 0.4 N per needle, and exhibits a high swelling ratio of 700% that facilitates timely extraction of sufficient ISF for biomarker analysis. For proof-of-concept, it realizes detection of miRNAs and Cu2+ efficiently and quantitatively in an agarose skin and fresh porcine cadaver skin model. Given the good sampling and in situ monitoring ability, the MN array holds great promise for skin ISF-based applications.

3.
J Colloid Interface Sci ; 606(Pt 2): 1239-1248, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492462

RESUMO

Cuprous oxide (Cu2O) is a p-type semiconductor with excellent catalytic activity and stability that has gained much attention because it is non-toxic, abundant, and inexpensive. Porous carbon materials have large specific surface areas, which offer abundant electroactive sites, enhance the electrical conductivity of materials, and prevent the aggregation of Cu2O nanocubes. In this study, a composite with high electrocatalytic activity was prepared based on Cu2O nanocubes anchored onto three-dimensional macroporous carbon (MPC) by a simple, eco-friendly, and cheap method for hydrazine detection. Due to the synergistic effect of MPC and Cu2O, the sensor exhibited high electrocatalytic activity, sensitivity, better selectivity, and low limit of detection. The resulting sensor could be a sensitive and effective platform for detecting hydrazine and promising practical applications.


Assuntos
Carbono , Cobre , Hidrazinas
4.
Exp Ther Med ; 22(6): 1451, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34721693

RESUMO

Patients treated with 5-fluorouracil (5-FU) can develop rare but potentially severe cardiac effects, including cardiomyopathy, angina pectoris, heart failure and cardiogenic shock. The specific pathologies and underlying mechanisms are yet to be fully understood. The results of previous studies have indicated that mitochondrial autophagy is widely detected in many angiocardiopathies. In the present study, the dynamic changes in the homeostasis of mitochondrial injury and autophagy were observed in rats treated with 5-FU for different durations. A corresponding control group and a 5-FU model group were established in groups of Sprague-Dawley rats aged 2 and 18 months, and the myocardial enzyme levels were determined at different time points. At 2 weeks post-model establishment, cardiac ultrasound and myocardial histological staining were performed, cardiomyocyte apoptosis and myocardial mitochondrial function were assessed, and mitochondrial ultrastructure was examined. In addition, the expression levels of autophagy-related proteins were evaluated in the 18-month-old rats on days 7 and 14 of 5-FU administration. The experimental results demonstrated that 5-FU induced an elevation in the levels of myocardial enzymes, as well as changes in the cardiac structure and function, and that these changes were more prominent over longer drug durations. In addition, 5-FU decreased the levels of myocardial mitochondrial ATP and mitochondrial membrane potential, and aggravated myocardial fibrosis and cardiomyocyte apoptosis compared with those observed in the untreated control group, treated with the same volume of saline as 5-FU in the 5-FU group. These injuries were particularly evident in aging rats. Notably, 5-FU increased the expression levels of myocardial mitochondrial autophagy-related proteins, and electron microscopy revealed a more severe autophagic state in the model groups compared with that in the control groups. In conclusion, 5-FU induced myocardial mitochondrial damage, the degree of which was more severe in aging rats compared with that in young rats. The mitochondrial autophagy induced by 5-FU was excessive, and the degree of autophagy was aggravated with increased 5-FU administration time.

5.
Neuroimage ; 245: 118713, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34798231

RESUMO

The current evolution of 'cloud neuroscience' leads to more efforts with the large-scale EEG applications, by using EEG pipelines to handle the rapidly accumulating EEG data. However, there are a few specific cloud platforms that seek to address the cloud computational challenges of EEG big data analysis to benefit the EEG community. In response to the challenges, a WeBrain cloud platform (https://webrain.uestc.edu.cn/) is designed as a web-based brainformatics platform and computational ecosystem to enable large-scale EEG data storage, exploration and analysis using cloud high-performance computing (HPC) facilities. WeBrain connects researchers from different fields to EEG and multimodal tools that have become the norm in the field and the cloud processing power required to handle those large EEG datasets. This platform provides an easy-to-use system for novice users (even no computer programming skills) and provides satisfactory maintainability, sustainability and flexibility for IT administrators and tool developers. A range of resources are also available on https://webrain.uestc.edu.cn/, including documents, manuals, example datasets related to WeBrain, and collected links to open EEG datasets and tools. It is not necessary for users or administrators to install any software or system, and all that is needed is a modern web browser, which reduces the technical expertise required to use or manage WeBrain. The WeBrain platform is sponsored and driven by the China-Canada-Cuba international brain cooperation project (CCC-Axis, http://ccc-axis.org/), and we hope that WeBrain will be a promising cloud brainformatics platform for exploring brain information in large-scale EEG applications in the EEG community.

6.
Cent Eur J Immunol ; 46(2): 140-151, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34764783

RESUMO

Introduction: Atherosclerosis (AS) is the leading cause of cardiovascular disease. Circular RNA hsa_circ_0003204 (hsa_circ_0003204) was elevated in oxidized low-density lipoprotein (ox-LDL)-induced human umbilical vein endothelial cells. However, the role and molecular mechanism of hsa_circ_0003204 in the AS process have not been studied. Material and methods: Human primary aortic endothelial cells (HAECs) were treated with low-density lipoprotein (ox-LDL) to establish the AS model. The viability of ox-LDL-induced HAECs was assessed by counting kit-8 (CCK8) assay. Reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD) levels in ox-LDL-induced HAECs supernatant were evaluated with the relevant kits. The apoptosis of ox-LDL-induced HAECs was determined via flow cytometry assay. The expression of hsa_circ_0003204, miR-330-5p, and nucleotide-binding oligomerization domain 2 (Nod2) was analyzed through quantitative real-time polymerase chain reaction (qRT-PCR). The relationship between hsa_circ_0003204 or Nod2 and miR-330-5p was verified by dual-luciferase reporter assay. Protein level of Nod2 was detected using western blot analysis. Results: Hsa_circ_0003204 and Nod2 were upregulated while miR-330-5p was decreased in ox-LDL-induced HAECs. Hsa_circ_0003204 depletion restrained the oxidative stress and apoptosis of ox-LDL-induced HAECs. Notably, hsa_circ_0003204 regulated Nod2 expression via sponging miR-330-5p in HAECs. Moreover, miR-330-5p inhibition restored the constraint of the oxidative stress and apoptosis of ox-LDL-induced HAECs caused by hsa_circ_0003204 silencing. Additionally, miR-330-5p targeted Nod2 and Nod2 enhancement abolished the repressive effects of miR-330-5p overexpression on the oxidative stress and apoptosis of ox-LDL-induced HAECs. Conclusions: Hsa_circ_0003204 exhaustion mitigated endothelial cell injury through suppressing the oxidative stress and apoptosis in ox-LDL-induced HAECs via the miR-330-5p/Nod2 axis.

7.
Opt Express ; 29(21): 32818-32825, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34809104

RESUMO

Angle-resolved polarized (ARP) Raman spectroscopy can be utilized to characterize the Raman modes of two-dimensional layered materials based on crystal symmetry or crystal orientation. In this paper, the polarization properties of E 1 2g and A1g modes on the basal plane and edge plane of high purity 2H-MoS2 bulk crystal grown by chemical vapor transport (CVT) method were investigated by ARP Raman spectroscopy. The I and II type ARP Raman spectroscopy with four kinds of polarization configurations: αY, αX, ßY, and ßX were used to explore the intensity dependence of E 1 2g and A1g modes at different planes on the polarization direction of incident/scattered light. The results show that the E 1 2g and A1g modes exhibit different polarization properties dependent on the polarization of the incident laser and the in-plane rotation of the sample at different planes. The experimental results were confirmed and analyzed through theoretical calculation. Our work sheds light on the intriguing effect of the subtle atomic structure in stacked MoS2 layers on the resulting ARP Raman properties. This provides a reference for the study of other two-dimensional layered crystalline materials by ARP Raman spectroscopy.

8.
Materials (Basel) ; 14(21)2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34772073

RESUMO

Benzocyclobutene-modified silsesquioxane (BCB-POSS) and divinyl tetramethyl disiloxane-bisbenzocyclobutene (DVS-BCB) prepolymer were introduced into the containing benzocyclobutene (BCB) unit matrix resin P(4-MB-co-1-MP) polymerized from 1-methyl-1-(4-benzocyclobutenyl) silacyclobutane (4-MSCBBCB) and 1-methyl-1-phenylsilacyclobutane (1-MPSCB), respectively. The low dielectric constant (low-k) siloxane/carbosilane hybrid benzocyclobutene resin composites, P(4-MB-co-1-MP)/BCB-POSS and P(4-MB-co-1-MP)/DVS-BCB, were prepared. The curing processes of the composites were assessed via Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The effects on dielectric properties and heat resistance of those composites with different proportion of BCB-POSS and DVS-BCB were investigated using an impedance analyzer and thermogravimetric analyzer (TGA), respectively. The thermal curing of composites could be carried out by ring-opening polymerization (ROP) of the BCB four-member rings of BCB-POSS or DVS-BCB and those of P(4-MB-co-1-MP). With increasing the proportion of BCB-POSS to 30%, the 5% weight loss temperature (T5%) of P(4-MB-co-1-MP)/BCB-POSS composites was raised visibly, whereas the dielectric constant (k) was decreased owing to the introduction of nanopores into POSS. For P(4-MB-co-1-MP)/DVS-BCB composites, the T5% and k were slightly raised with increasing the proportion of DVS-BCB. The above results indicated that the BCB-POSS showed advantages over conventional fillers to simultaneously improve thermostability and decrease k.

9.
Front Cell Dev Biol ; 9: 724310, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34604224

RESUMO

Dermal papillae are a target of androgen action in patients with androgenic alopecia, where androgen acts on the epidermis of hair follicles in a paracrine manner. To mimic the complexity of the dermal papilla microenvironment, a better culture model of human dermal papilla cells (DPCs) is needed. Therefore, we evaluated the inhibitory effect of dihydrotestosterone (DHT)-treated two-dimensional (2D)- and 3D-cultured DPCs on hair follicle growth. 2D- and 3D-cultured DPC proliferation was inhibited after co-culturing with outer root sheath (ORS) cells under DHT treatment. Moreover, gene expression levels of ß-catenin and neural cell adhesion molecules were significantly decreased and those of cleaved caspase-3 significantly increased in 2D- and 3D-cultured DPCs with increasing DHT concentrations. ORS cell proliferation also significantly increased after co-culturing in the control-3D model compared with the control-2D model. Ki67 downregulation and cleaved caspase-3 upregulation in DHT-treated 2D and 3D groups significantly inhibited ORS cell proliferation. Sequencing showed an increase in the expression of genes related to extracellular matrix synthesis in the 3D model group. Additionally, the top 10 hub genes were identified, and the expression of nine chemokine-related genes in DHT-treated DPCs was found to be significantly increased. We also identified the interactions between transcription factor (TF) genes and microRNAs (miRNAs) with hub genes and the TF-miRNA coregulatory network. Overall, the findings indicate that 3D-cultured DPCs are more representative of in vivo conditions than 2D-cultured DPCs and contribute to our understanding of the molecular mechanisms underlying androgen-induced alopecia.

10.
Artigo em Inglês | MEDLINE | ID: mdl-34643312

RESUMO

Lysosome-relevant cell death induced by lysosomal membrane permeabilization (LMP) has recently attracted increasing attention. However, nearly no studies show that currently available LMP inducers can evoke immunogenic cell death (ICD) or convert immunologically cold tumors to hot. Herein, we report a LMP inducer named TPE-Py-pYK(TPP)pY, which can respond to alkaline phosphatase (ALP), leading to formation of nanoassembies along with fluorescence and singlet oxygen turn-on. TPE-Py-pYK(TPP)pY tends to accumulate in ALP-overexpressed cancer cell lysosomes as well as induce LMP and rupture of lysosomal membranes to massively evoke ICD. Such LMP-induced ICD effectively converts immunologically cold tumors to hot as evidenced by abundant CD8+ and CD4+ T cells infiltration into the cold tumors. Exposure of ALP-catalyzed nanoassemblies in cancer cell lysosomes to light further intensifies the processes of LMP, ICD and cold-to-hot tumor conversion. This work thus builds a new bridge between lysosome-relevant cell death and cancer immunotherapy.

11.
Int J Low Extrem Wounds ; : 15347346211046203, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34665051

RESUMO

To systematically evaluate the clinical effects of platelet-rich plasma in the treatment of lower limb venous ulcers by applying a meta-analysis method. The Pubmed, Cochrance Library, Embase, and OVID EBM Reviews databases were searched for the search terms'platelet-rich plasma" or "Plasma, Platelet-Rich" or "Platelet Rich Plasma" and "lower extremity venous ulcers' or "Leg Ulcers' or "Ulcer, Leg", and a meta-analysis was performed on the published research literature on platelet-rich plasma for lower extremity venous ulcers from January 1900 to April 2021. The outcome indicators were: post-treatment trauma area and healing rate. Revman 5.3 statistical software was applied for meta-analysis. A total of 294 patients with lower extremity venous ulcers were included in six publications, including 148 patients in the experimental group treated with PRP versus 146 patients in the control group treated with conventional therapy. There was a statistically significant difference in the Formula of an ellipse at the end of treatment (CM²) between the experimental group and the control group, with a mean difference of -1.19 (95% CI -1.80 to -0.58, P = .0001; 6 studies, 294 participants moderate quality of evidence). The difference between the healing rate of the experimental group and the control group was statistically significant, with a risk ratio (RR) of 5.73 (95% CI 3.29 - 9.99, P < .00001; 5 studies, 248 participants moderate quality of evidence).There may be publication bias for both Formula of an ellipse at the end of treatment and healing rate. This comprehensive meta-analysis of available evidence suggests that the application of PRP for lower extremity venous ulcers accelerates the wound healing process and improves wound healing rates.

12.
Nat Commun ; 12(1): 5269, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34489432

RESUMO

Thermoelectrics are suited to converting dissipated heat into electricity for operating electronics, but the small voltage (~0.1 mV K-1) from the Seebeck effect has been one of the major hurdles in practical implementation. Here an approach with thermo-hydro-electrochemical effects can generate a large thermal-to-electrical energy conversion factor (TtoE factor), -87 mV K-1 with low-cost carbon steel electrodes and a solid-state polyelectrolyte made of polyaniline and polystyrene sulfonate (PANI:PSS). We discovered that the thermo-diffusion of water in PANI:PSS under a temperature gradient induced less (or more) water on the hotter (or colder) side, raising (or lowering) the corrosion overpotential in the hotter (or colder) side and thereby generating output power between the electrodes. Our findings are expected to facilitate subsequent research for further increasing the TtoE factor and utilizing dissipated thermal energy.

13.
Front Biosci (Landmark Ed) ; 26(9): 475-484, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34590460

RESUMO

Backgrounds: To evaluate the predictive power of 18F-Fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) derived radiomics in molecular subtype classification of breast cancer (BC). Methods: A total of 273 primary BC patients who underwent a 18F-FDG PET/CT imaging prior to any treatment were included in this retrospective study, and the values of five conventional PET parameters were calculated, including the maximum standardized uptake value (SUVmax), SUVmean, SUVpeak, metabolic tumor volume (MTV), and total lesion glycolysis (TLG). The ImageJ 1.50i software and METLAB package were used to delineate the contour of BC lesions and extract PET/CT derived radiomic features reflecting heterogeneity. Then, the least absolute shrinkage and selection operator (LASSO) algorithm was used to select optimal subsets of radiomic features and establish several corresponding radiomic signature models. The predictive powers of individual PET parameters and developed PET/CT derived radiomic signature models in molecular subtype classification of BC were evaluated by using receiver operating curves (ROCs) analyses with areas under the curve (AUCs) as the main outcomes. Results: All of the three SUV parameters but not MTV nor TLG were found to be significantly underrepresented in luminal and non-triple (TN) subgroups in comparison with corresponding non-luminal and TN subgroups. Whereas, no significant differences existed in all the five conventional PET parameters between human epidermal growth factor receptor 2+ (HER2+) and HER2- subgroups. Furthermore, all of the developed radiomic signature models correspondingly exhibited much more better performances than all the individual PET parameters in molecular subtype classification of BC, including luminal vs. non-luminal, HER2+ vs. HER2-, and TN vs. non-TN classification, with a mean value of 0.856, 0.818, and 0.888 for AUC. Conclusions: PET/CT derived radiomic signature models outperformed individual significant PET parameters in molecular subtype classification of BC.

14.
Syst Appl Microbiol ; 44(5): 126234, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34343788

RESUMO

Rpf protein, a kind of resuscitation promoting factor, was first found in the culture supernatant of Micrococcus luteus. It can resuscitate the growth of M. luteus in "viable but non-culture, VBNC" state and promote the growth of Gram-positive bacteria with high G + C content. This paper investigates the resuscitating activity of M. luteus ACCC 41016T Rpf protein, which was heterologously expressed in E. coli, to cells of M. luteus ACCC 41016T and Rhodococcus marinonascens HBUM200062 in VBNC state, and examines the effect on the cultivation of actinobacteria in soil. The results showed that the recombinant Rpf protein had resuscitation effect on M. luteus ACCC 41016T and R. marinonascens HBUM200062 in VBNC state. 83 strains of actinobacteria, which were distributed in 9 families and 12 genera, were isolated from the experimental group with recombinant Rpf protein in the culture medium. A total of 41 strains of bacteria, which were distributed in 8 families and 9 genera, were isolated from the control group without Rpf protein. The experimental group showed richer species diversity than the control group. Two rare actinobacteria, namely HBUM206391T and HBUM206404T, were obtained in the experimental group supplemented with Rpf protein. Both may be potential new species of Actinomadura and Actinokineospora, indicating that the recombinant expression of M. luteus ACCC 41016T Rpf protein can effectively promote the isolation and culture of actinobacteria in soil.


Assuntos
Actinobacteria , Proteínas de Bactérias/metabolismo , Citocinas/metabolismo , Micrococcus luteus/metabolismo , Microbiologia do Solo , Actinobacteria/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Citocinas/genética , Escherichia coli , Rhodococcus
15.
Medicine (Baltimore) ; 100(34): e27064, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34449500

RESUMO

BACKGROUND: Dexmedetomidine (Dexm), a selective alpha-2 adrenoceptor agonist, and dexamethasone (Dexa), a very potent and highly selective glucocorticoid, have both been proven effectively to prolong the duration of local anesthetics (LA) in regional anesthesia. However, data comparing the efficacy of Dexm and Dexa as perineural adjuvants are inconsistent. Therefore, this systematic review and meta-analysis of randomized and quasi-randomized controlled trials (RCTs) was conducted to compare the effects of Dexm and Dexa when used as LA adjuvants on peripheral nerve block (PNB). METHODS: We systematically searched PubMed, Cochrane Library, EMBASE, Web of Science, and ScienceDirect databases up to October, 2020. The primary outcome was the duration of analgesia. Secondary outcomes included incidence of rescue analgesia, cumulative opioid consumption, time required for onset of sensory and motor blockades, duration of sensory and motor blockades, incidence of postoperative nausea and vomiting (PONV), and side effect-associated outcomes (e.g., bradycardia, sedation, hypotension, rates of infection, and neurological complications). The study was registered on PROSPERO, number CRD42020188796. RESULTS: After screening of full-text relevant articles, 13 RCTs that met the inclusion criteria were retrieved for this systematic review. It was revealed that perineural Dexm provided equivalent analgesic duration to perineural Dexa. Besides, the intake of Dexm increased the incidence of rescue analgesia in limbs surgery, as well as the cumulative opioid consumption, and decreased the time required for onset of sensory and motor blockades for long-acting LA (all P < .05). Other analysis revealed insignificant difference between the 2 groups in terms of the incidence of PONV (P > .05). Additionally, 2 studies demonstrated that Dexm possesses more sedative properties than Dexa (P < .05). CONCLUSIONS: This meta-analysis indicated that the analgesic duration of Dexm and Dexa as LA adjuvants in PNB is the same. Meanwhile, the effects of perineural Dexm and Dexa on some secondary outcomes, including the incidence of rescue analgesia, cumulative opioid consumption, and time required for onset of sensory and motor blockades, are associated with the surgical site and type of LA.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/uso terapêutico , Anestesia Local/métodos , Dexametasona/uso terapêutico , Dexmedetomidina/uso terapêutico , Glucocorticoides/uso terapêutico , Bloqueio Nervoso/métodos , Adjuvantes Anestésicos , Agonistas de Receptores Adrenérgicos alfa 2/administração & dosagem , Dexametasona/administração & dosagem , Dexmedetomidina/administração & dosagem , Glucocorticoides/administração & dosagem , Humanos , Nervos Periféricos , Ensaios Clínicos Controlados Aleatórios como Assunto
16.
Opt Express ; 29(13): 20262-20274, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34266119

RESUMO

In this study, a quasi-omnidirectional underwater wireless optical communication (UWOC) system is implemented with a prismatic array consisting of three uniformly distributed high-power LED modules as the transmitter. Over a 10-m underwater channel in a 50-m standard swimming pool, a data rate of 22 Mbps is achieved without adopting any digital signal processing algorithm. With zero forcing (ZF) based frequency domain equalization (FDE) and a maximum ratio combining (MRC) algorithm, the maximum net data rates achieved are 69.65 Mbps, 39.8 Mbps and 29.85 Mbps over 10-m, 30-m, and 40-m underwater channels, respectively. In the proposed UWOC system, the receiver could successfully capture optical signals at different directions from the transmitter and the bit error rates (BERs) measured in different directions show small fluctuations. The proposed system could meet the demands of high-speed data transmission among units in a swarm-robot system and last meter user access in an underwater optical cellular network system.

17.
J Colloid Interface Sci ; 601: 338-345, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34087594

RESUMO

Development of high-performance, economic, and stable non-noble metal catalysts is a still formidable challenge in hydrogen evolution reaction (HER) that must be overcome to alleviate the energy and environmental crisis. Herein, we designed and fabricated N-doped carbon nanoframes encapsulated by CoP nanoparticles (CoP-NCN). The 3D porous structure of the ZIF-67-derived N-doped carbon shortened the charge and mass transport pathways, contributing to enhanced electrocatalytic performance. Moreover, the synergistic effects of excellent conductivity, abundant mesopores, and high-activity CoP nanoparticles led to remarkable electrocatalytic activity toward HER with an extremely low overpotential of 120 mV at 10 mA cm-2 and long-term stability. We further indicate that the fantastic HER catalytic ability of CoP-NCN is attributed to the good conductivity and the abundant active sites. The present study provides a promising avenue toward the design of cost-effective HER electrocatalysts.


Assuntos
Hidrogênio , Nanopartículas , Carbono , Catálise , Porosidade
18.
iScience ; 24(6): 102576, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34151229

RESUMO

Graphene oxide (GO) nanosheets with unique structure have received much attention in providing opportunity for high-performance membranes in separation. However, the rational design of ultrathin graphene membranes with controlled structures remains a big challenge. Here, we report a methodology to synthesize dual metal-coordinated ultrathin nanoporous graphene nanofilms by tailoring well-aligned nanocrystals as building blocks on heteroatom-doped GO nanosheets with tunable architectures. Manipulation of metal nitrate as bifunctional dopants realizes N-doping of graphene oxide and preferential growth of α-Mn2O3 nanocrystals. Generation of Mn-O-C bond during cross-linking greatly strengthens the stability of membranes for long-term steady operation. Meanwhile, because of spatial confinement effects and high binding energy, N-doped reduced GO nanosheets are desirable supports to construct numerous Mn-N-C bonds, thus generating artificial nanopores to significantly increase nanochannels for ultrafast mass transport. Moreover, the size-selective permeability of ultrathin nanoporous GO-based nanofilms can be optimized by managing the types of metal source for target coordination.

19.
Zhongguo Zhen Jiu ; 41(5): 511-4, 2021 May 12.
Artigo em Chinês | MEDLINE | ID: mdl-34002564

RESUMO

OBJECTIVE: To compare the clinical effect of wheat grain moxibustion and warming acupuncture on chronic superficial gastritis of spleen-stomach deficiency and cold. METHODS: A total of 200 patients with chronic superficial gastritis of spleen-stomach deficiency and cold were randomly divided into a wheat grain moxibustion group (100 cases, 13 cases dropped off ) and a warming acupuncture group (100 cases, 16 cases dropped off ). The acupoints of Zhongwan (CV 12), Tianshu (ST 25), Qihai (CV 6), Liangqiu (ST 34) and Zusanli (ST 36) were selected in both groups. The patients in the wheat grain moxibustion group were treated with wheat grain moxibustion, and 5 cone were given on every acupoint each time. Moxibustion was performed after acupuncture in the warming acupuncture group, and 3 cone each acupoint. Both groups were treated every other day for 15 times. The scores of clinical symptoms and signs, scores of physical component summary (PCS) and mental component summary (MCS) of quality of life in the two groups were recorded before and after treatment and during follow-up 1 month after treatment, and the clinical effects of the two groups were evaluated after treatment and during follow-up. RESULTS: After treatment and during follow-up, the scores of clinical symptoms and signs of the two groups were lower than before treatment (P<0.05), and the scores of PCS and MCS of quality of life were higher than before treatment (P<0.05). At follow-up, the score of clinical symptoms and signs in the wheat grain moxibustion group was lower than that in the warming acupuncture group (P<0.01), and the scores of PCS and MCS of quality of life were higher than those in the warming acupuncture group (P<0.001). The total effective rate of the wheat grain moxibustion group was 93.1% (81/87), which was higher than 82.1% (69/84) of the warming acupuncture group at follow-up (P<0.001). CONCLUSION: The wheat grain moxibustion can effectively improve the clinical symptoms, signs and quality of life in patients with chronic superficial gastritis of spleen-stomach deficiency and cold, and its long-term effect is better than warming acupuncture.


Assuntos
Terapia por Acupuntura , Moxibustão , Pontos de Acupuntura , Humanos , Qualidade de Vida , Baço , Estômago , Triticum
20.
Brain Topogr ; 34(4): 403-414, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33950323

RESUMO

"Bad channels" are common phenomena during scalp electroencephalography (EEG) recording that arise due to various technique-related reasons, and reconstructing signals from bad channels is an inevitable choice in EEG processing. However, current interpolation methods are all based on purely mathematical interpolation theory, ignoring the neurophysiological basis of the EEG signals, and their performance needs to be further improved, especially when there are many scattered or adjacent bad channels. Therefore, a new interpolation method, named the reference electrode standardization interpolation technique (RESIT), was developed for interpolating scalp EEG channels. Resting-state and event-related EEG datasets were used to investigate the performance of the RESIT. The main results showed that (1) assuming 10% bad channels, RESIT can reconstruct the bad channels well; (2) as the percentage of bad channels increased (from 2% to 85%), the absolute and relative errors between the true and RESIT-reconstructed signals generally increased, and the correlations between the true and RESIT signals decreased; (3) for a range of bad channel percentages (2% ~ 85%), the RESIT had lower absolute error (approximately 2.39% ~ 33.5% reduction), lower relative errors (approximately 1.3% ~ 35.7% reduction) and higher correlations (approximately 2% ~ 690% increase) than traditional interpolation methods, including neighbor interpolation (NI) and spherical spline interpolation (SSI). In addition, the RESIT was integrated into the EEG preprocessing pipeline on the WeBrain cloud platform ( https://webrain.uestc.edu.cn/ ). These results suggest that the RESIT is a promising interpolation method for both separate and simultaneous EEG preprocessing that benefits further EEG analysis, including event-related potential (ERP) analysis, EEG network analysis, and strict group-level statistics.


Assuntos
Encéfalo , Couro Cabeludo , Eletrodos , Eletroencefalografia , Humanos , Padrões de Referência
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