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1.
J Hazard Mater ; : 127828, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34815121

RESUMO

Visible light catalysis has been widely coupled with persulfate activation for refractory pollutants removal, while the exact role of persulfate played in such composite system is still questionable. In this work, the relation between peroxymonosulfate (PMS) induced structure change and visible light responsive activity of inverse spinel: i.e., Zn2SnO4, was deciphered. Under the visible light illumination (λ> 420nm) PMS addition would endow the composite system with pollutant removal performance. Batch test revealed that 60% of bisphenol-A (5 mg L-1) was mineralized within 3 h reaction time, by dosing 0.81 mM PMS and 0.1 g L-1 catalyst. The above oxidative system was also effective for other refractory pollutants elimination. Further analysis indicated that PMS could reduce the band gap of spinel from 2.75 to 2.52 eV and thereby enabling its visible light activity. Photogenerated h+ induced •OH and e- mediated •O2- contributed to the pollutant removal while h+ played a leading role. Density functional theory revealed that PMS would capture oxygen atom of spinel and induce surface oxygen vacancy defect structure formation. Also, three-oxygen atom coordinated Zn was identified as the possible catalyze site. This work is valuable for deep understanding the exact role of persulfate in photocatalytic system.

2.
Opt Express ; 29(20): 32728-32738, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34615337

RESUMO

In this paper, we experimentally propose a feasible and low spatial complexity adaptive artificial neural network (AANN) post-equalization algorithm in MIMO visible light communication (VLC) systems. By introducing the power ratio and the MIMO least mean square (MIMO-LMS) post-equalization algorithm into the structure design process of the artificial neural network (ANN) post-equalization algorithm, we reduced the spatial complexity of the post-ANN equalization algorithm to less than 10%. At the same time, the bit error rate (BER) performance of AANNs did not decrease. Finally, we achieved a data rate of 2.1Gbps in the AANN equalized 16QAM superposition coding modulation (SCM) and carrier-less amplitude-phase (CAP) single-receiver MIMO (SR-MIMO) VLC system.

3.
Nat Immunol ; 22(10): 1268-1279, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34556885

RESUMO

Metabolic inflammation is closely linked to obesity, and is implicated in the pathogenesis of metabolic diseases. FTO harbors the strongest genetic association with polygenic obesity, and IRX3 mediates the effects of FTO on body weight. However, in what cells and how IRX3 carries out this control are poorly understood. Here we report that macrophage IRX3 promotes metabolic inflammation to accelerate the development of obesity and type 2 diabetes. Mice with myeloid-specific deletion of Irx3 were protected against diet-induced obesity and metabolic diseases via increasing adaptive thermogenesis. Mechanistically, macrophage IRX3 promoted proinflammatory cytokine transcription and thus repressed adipocyte adrenergic signaling, thereby inhibiting lipolysis and thermogenesis. JNK1/2 phosphorylated IRX3, leading to its dimerization and nuclear translocation for transcription. Further, lipopolysaccharide stimulation stabilized IRX3 by inhibiting its ubiquitination, which amplified the transcriptional capacity of IRX3. Together, our findings identify a new player, macrophage IRX3, in the control of body weight and metabolic inflammation, implicating IRX3 as a therapeutic target.


Assuntos
Proteínas de Homeodomínio/metabolismo , Inflamação/metabolismo , Macrófagos/metabolismo , Obesidade/metabolismo , Fatores de Transcrição/metabolismo , Adipócitos/metabolismo , Adulto , Animais , Peso Corporal/fisiologia , Linhagem Celular , Diabetes Mellitus Tipo 2/metabolismo , Dieta/métodos , Células HEK293 , Humanos , Masculino , Doenças Metabólicas/metabolismo , Camundongos , Células RAW 264.7 , Células THP-1 , Termogênese/fisiologia , Transcrição Genética/fisiologia , Adulto Jovem
4.
Opt Express ; 29(14): 21773-21782, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34265957

RESUMO

Visible light communication (VLC) system has emerged as a promising solution for high-speed underwater data transmission. To tackle with the linear and nonlinear impairments, deep learning inspired equalization is introduced into VLC. Despite their success in accuracy, deep learning approaches often come with high computational budget. In this paper, we propose an adaptive deep-learning equalizer based on complex-valued neural network and constellation partitioning scheme for 64 QAM-CAP modulated underwater VLC (UVLC) system. Inspired by the fact that symbols modulated at different levels experience various extent of nonlinear distortion, we adaptively partition the received symbols in constellation and design compact equalization networks for specific regions to reduce computation consumption. Experiments demonstrate that the partitioned equalizer can achieve the bit error rate below the 7% hard-decision forward error correction (HD-FEC) limit of 3.8 × 10-3 at 2.85 Gbps similar to the standard complex-valued network, yet with 56.1% total computational complexity reduction. This work paves the path for online data processing in high speed UVLC system.

5.
J Environ Manage ; 291: 112725, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33962290

RESUMO

Riboflavin is commercially produced primarily by bio-fermentation. Nonetheless, purification and separation are particularly complex and costly. Adsorption from the fermentation liquor is an alternative riboflavin separation technology during which a cost-efficient adsorbent is highly desired. In this study, a low-cost activated algal biomass-derived biochar (AABB) was applied as an adsorbent to efficiently adsorb riboflavin from an aqueous solution. The adsorption capacity of riboflavin on AABB increased with the increase in pyrolysis temperature and initial riboflavin concentration. The adsorption isotherms were well described by the Freundlich and Langmuir models. The AABB displayed excellent adsorption performance and its maximum adsorption capacity was 476.9 mg/g, which was 6.8, 6.8, and 5.2 times higher than that of laboratory-prepared activated rape straw biochar, activated broadbean shell biochar and commercial activated carbon, respectively, which was mainly ascribed to its larger specific surface area and abundant functional groups. The mass transfer model results showed that mass transfer resistance was dependent on both the film mass transfer and porous diffusion. Raman and Fourier transform-infrared spectra confirmed the presence of π-π interactions and hydrogen bonding between riboflavin and the AABB. The adsorption of riboflavin onto AABB was a spontaneous process, which was dominated by van der Waals forces. These results will be beneficial for developing effective riboflavin recovery technologies and simultaneously utilizing waste algal blooms.


Assuntos
Carvão Vegetal , Poluentes Químicos da Água , Adsorção , Eutrofização , Concentração de Íons de Hidrogênio , Cinética , Riboflavina
6.
Opt Express ; 29(3): 3296-3308, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33770931

RESUMO

Deep neural network has been used to compensate the nonlinear distortion in the field of underwater visible light communication (UVLC) system. Considering the tradeoff between the equalization performance and the network complexity is the priority in practical applications. In this paper, we propose a novel hybrid frequency domain aided temporal convolutional neural network (TFCNN) with attention scheme as the post-equalizer in CAP modulated UVLC system. Experiments illustrate that the proposed TFCNN can achieve better equalization performance and remain the bit error rate (BER) below the 7% hard-decision forward error correction (HD-FEC) limit of 3.8×10-3 when other equalizers loss effectiveness under serious distortion condition. Compared with the standard deep neural network, TFCNN shows 76.4% network parameters complexity reduction.

7.
Opt Express ; 28(19): 28017-28032, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32988082

RESUMO

For the single receiver multiple-input-multiple-output (SR-MIMO) visible light communication (VLC) system, the superposing of two transmitters will introduce severe distortion in the time-domain and frequency-domain. In this paper, we first proposed a MIMO multi-branch hybrid neural network (MIMO-MBNN) as the post-equalizer in the SR-MIMO pulse amplitude magnitude eight levels (PAM8) VLC system. Compared with the traditional single-input-single-output least mean square equalizer with Volterra series (SISO-LMS) and SISO deep neural network (SISO-DNN), MIMO-MBNN can achieve at most 3.35 dB Q factor improvement. Furthermore, the operation range of MIMO-MBNN is at least 2.33 times of SISO-DNN and SISO-LMS among the measured signal peak to peak voltage. At last, 2.1 Gbps data rate is achieved by MIMO-MBNN below the 7% hard-decision forward error correction (HD-FEC) threshold. As far as we know, this is the highest data rate in the SR-MIMO VLC system.

8.
Opt Express ; 28(10): 15562-15572, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403581

RESUMO

We demonstrate a partial pruning strategy for a post-equalizer based on a dual-branch multilayer perceptron-based post-equalizer (DBMLP PE) in an underwater visible light communication (UVLC) system. The partial pruning strategy produces a sparse DBMLP PE (SDBMLP PE) with less space complexity than the Volterra PE and bit error rate (BER) performance similar to the DBMLP PE. We experimentally prove the effectiveness and necessity of the partial pruning algorithm in multilayer perceptron-based (MLP) PE. The partial pruning strategy consists of two parts: (i) preventing the pruning of connections to the output nodes, and (ii) avoiding the linear mapping branches of the DBMLP during the pruning process. Our experiments prove that the SDBMLP PE further reduces the BER of the UVLC system by 36.5%, with only 33.8% parameters of the Volterra PE. To the best of our knowledge, this paper presents the first deep neural network-based PE with lower complexity and higher BER performance than the Volterra PE in the UVLC system, which dramatically increases the applicability of artificial neural network-based (ANN) PE in the field of UVLC systems.

9.
Opt Express ; 28(8): 11319-11338, 2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32403646

RESUMO

Underwater visible light communication (UVLC) systems suffer from a strong nonlinear effect and high inter-symbol interference (ISI). In this study, to improve the performance of a UVLC system under such conditions, we propose a novel nonlinear hybrid modulation scheme named two-dimensional bit allocation (2DBA). By comparing the performance of 2DBA with the famous Levin-Campello (LC) algorithm and the quadrature amplitude modulation (QAM)-based time-domain hybrid modulation (TDHQ) algorithm, we have proved by analysis and experiment that 2DBA can outperform the power allocation-based LC algorithm and the TDHQ algorithm below the 3.8×10-3 hard decision forward error correction threshold (HD-FEC) when the system has a severe nonlinear effect and ISI. The data rate 3.24 Gb/s of 2DBA is measured after 1.2 m underwater transmission; as far as we know, this is the highest data rate reported in a blue LED chip based UVLC system.

10.
Opt Express ; 28(2): 2302-2316, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32121923

RESUMO

Compared with multicolor-chip integrated white LEDs, phosphor-based white LEDs are more attractive for daily illumination due to lower cost and complexity, and thus they are preferable for future commercial use of visible light communication (VLC) systems. However, the application of phosphorescent white LEDs has a lower data rate than multicolor-chip integrated LEDs because of severe nonlinear impairments and limited bandwidth caused by the slow-responding phosphor. In this paper, for the first time we propose to employ phosphorescent white LEDs based on silicon substrate with adaptive bit-loading discrete multitone (DMT) modulation and a memoryless polynomial based nonlinear equalizer to achieve a high-speed VLC system. We also present a comprehensive comparison among nonlinear equalizers based on the Volterra series model, memory polynomial model, memoryless polynomial model and deep neural network (DNN) with experimental results utilizing a silicon substrate phosphorescent white LED, and provide detailed suggestions on how to choose the most suitable nonlinear mitigation scheme considering different practical conditions and the tradeoff between complexity and performance. Beyond 3.00 Gb/s DMT VLC transmission over 1-m indoor free space is successfully demonstrated with bit error rate (BER) under the 7% forward error correction (FEC) limit of 3.8×10-3. As far as we know, this is the highest data rate ever reported for VLC systems based on a single high-power phosphorescent white LED.

11.
Chemosphere ; 244: 125577, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32050350

RESUMO

Persulfate based advanced oxidation process is a promising technology for refractory contaminants removal. Cobalt is considered as the most efficient metal in catalyzing peroxymonosulfate decomposition. Although different cobalt based nanomaterials have been developed, easy aggregation and metal ion leaching during catalytic reaction would result in its deficiency. To address the above issue, in this work, carbon supported Co/CoO core-shell nanocomposite was in-situ fabricated by using polyphenol-metal coordinate as precursor. Results indicated that cobalt nanoparticle with size of 10 nm was successfully prepared and well dispersed within the carbon matrix. By using as-prepared material as catalyst, 50 mg/L orange II was completely removed under the condition of 0.2 g/L peroxymonosulfate, 0.05 g/L catalyst, pH = 4.0-10.0. Both sulfate and hydroxyl radicals were formed during peroxymonosulfate decomposition, while sulfate radical dominated the pollutant removal. Mechanism study revealed that the cobalt was the key site for catalyzing peroxymonosulfate decomposition. This work might provide valuable information in designing and fabricating metal anchored carbon composite catalyst for efficiently and cost-effectively activate peroxymonosulfate.


Assuntos
Corantes/química , Nanocompostos/química , Peróxidos/química , Compostos Azo , Benzenossulfonatos , Carbono/química , Catálise , Cobalto/química , Modelos Químicos , Oxirredução , Sulfatos
12.
Sci Total Environ ; 705: 135959, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31841900

RESUMO

The sustainable management and recirculation of phosphorus resources are essential to our human lives. In this work, phosphorus removal and recovery from secondary effluent were achieved using municipal wastewater-derived materials as adsorbents. Through modification with 0.5 M NaOH for 30 min, iron containing sludge that originated from the coagulation pretreatment of municipal wastewater was successfully converted to phosphorus adsorbent. The maximal adsorption capacity of the prepared adsorbent was estimated to be 22 mg-P/g, and the adsorption performance remained stable in the pH range of 5-8. FeO(OH) was identified as the key adsorption site, and the ligand exchange mediated chemical adsorption was the main mechanism for phosphorus removal by the prepared material. Moreover, a laboratory-scale continuous-flow adsorption column experiment showed that the surplus phosphorus in secondary effluent could be readily reduced to <0.1 mg/L. By pyrolysis of P-laden alkali-treated iron sludge under oxygen limited conditions, the phosphorus was recovered and successfully applied to support wheat growth. This work provides valuable information for both the sustainable management of phosphorus streams in wastewater and cyclic utilization of waste sludge.

13.
Opt Express ; 27(16): 22532-22541, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31510544

RESUMO

This paper proposes a novel two tributaries heterogeneous neural network (TTHnet) based channel emulator, which is suitable for both estimating single-carrier and multi-carrier modulated channels of underwater visible light communication (UVLC). Compared to traditional neural networks, the TTHnet channel emulator has only 1932 trainable parameters, which is only 0.8% of multilayer perceptron (MLP) based channel emulator and 1% of a convolutional neural network (CNN) based channel emulator. Furthermore, it provides a more accurate estimation of the UVLC channel and greater interpretability than MLP and CNN. The experiments in this paper use carrier-less amplitude/phase modulation (CAP) and discrete multi-tone modulation (DMT) as representative examples of single-carrier and multi-carrier modulation, respectively. The experiment proves that the TTHnet based channel emulator could effectively emulate the channel response of UVLC systems both in time and frequency domain. To the best of our knowledge, this is the first time that the single-carrier and multi-carrier modulated UVLC channel is emulated by the deep neural networks based channel emulator, which will effectively accelerate the research progress of UVLC and reduce research costs of UVLC systems.

14.
Sci Total Environ ; 681: 56-65, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31102817

RESUMO

The inhibitory effects of oxytetracycline (OTC) on the anaerobic ammonium oxidation (anammox) performance were relieved by employing bio-augmentation (BA) tactics. However, the recovery mechanism was vague. The response of specific anammox activity (SAA), heme c, functional genes, extracellular polymeric substance (EPS) and antibiotics resistance genes (ARGs) to OTC inhibition and BA aid were traced in the present study. The results indicated that response of SAA, heme c content and functional genes, such as nirS, hzsA and hdh to OTC inhibition were not synchronous. The presence of the tetC, tetG, tetX, and intI1 genes enhanced the resistance of anammox sludge to OTC, thus accelerating the performance recovery when aided by BA. A significant correlation existed between number of anammox 16S rRNA gene copies and protein level in the soluble microbial products (SMP), between tetG gene relative abundance and polysaccharose in SMP and between tetG gene relative abundance and protein in bound EPS (EPSs). In nutshell, the current findings provide the first description of a recovery mechanism regarding OTC-inhibited anammox performance aided by BA based on functional genes and highlights the contribution of ARGs and the self-resistance ability of EPS.


Assuntos
Antibacterianos/toxicidade , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Oxitetraciclina/toxicidade , Matriz Extracelular de Substâncias Poliméricas , RNA Ribossômico 16S , Esgotos
15.
Front Vet Sci ; 6: 482, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31998763

RESUMO

Hemagglutination inhibition (HI) and virus neutralization antibody (nAb) do not always correlate with the protection of H7 avian influenza vaccines in mammals and humans. The contribution of different classes of antibodies induced by H7N9 vaccines to protection is poorly characterized in chickens. In this study, antibody responses induced by both inactivated and viral-vectored H7N9 vaccines in chickens were dissected. Chickens immunized with inactivated H7N9 vaccine showed 50% seroconversion rate and low HI and nAb titers at week 3 post immunization. However, inactivated H7N9 vaccine elicited 100% seroconversion rate in terms of high levels of HA-binding IgG antibody determined by ELISA. Despite inducing low levels of nAb, inactivated H7N9 vaccine conferred full protection against H7N9 challenge in chickens and markedly inhibited virus shedding. Similarly, Newcastle disease virus (NDV)-vectored H7N9 vaccine induced marginal HI and nAb titers but high level of IgG antibody against H7N9 virus. In addition, NDV-H7N9 vaccine also provided complete protection against H7N9 challenge. Chicken antisera had a high IgG/VN ratio, indicating that a larger proportion of serum antibodies were non-neutralizing antibody (non-nAb). More importantly, passive transfer challenge experiment showed that non-neutralizing antisera provided partial protection (37.5%) of chickens against H7N9 challenge, without significant difference from that provided by neutralizing antisera. In conclusion, our results suggest that antibodies measured by the traditional HI and virus neutralization assays do not correlate with the protection of inactivated and viral-vectored H7N9 vaccines in chickens, and HA-binding non-nAb also contributes to the protection against H7N9 infection. Total binding antibody can be used as a key correlate to the protection of H7N9 vaccine.

16.
Opt Express ; 26(20): 26700-26712, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30469751

RESUMO

In this paper, we demonstrate a novel Gaussian kernel-aided deep neural network (GK-DNN) equalizer that can effectively compensate for the high nonlinear distortion of underwater PAM8 visible light communication (VLC) channels. The application of a Gaussian kernel can reduce the necessary training iterations to 47.06%, enabling it to outperform the traditional DNN equalizer. At the same time, a novel design strategy with respect to the structure of the GK-DNN equalizer is proposed, which can effectively save computing resources and reduce the data volume of the necessary training data set. By using the GK-DNN equalizer, a 1.5 Gbps PAM8 VLC system over 1.2-m underwater transmission is successfully demonstrated.

17.
Hu Li Za Zhi ; 65(3): 58-70, 2018 06.
Artigo em Chinês | MEDLINE | ID: mdl-29790140

RESUMO

BACKGROUND: While cardiac resynchronization therapy improves the quality of life of patients with heart failure, some psychological and behavioral factors still affect the quality of life of these patients. However, information on the factors that affect the quality of life of these patients is limited. PURPOSE: To describe the quality of life and investigate the relationship between quality of life and behavioral and psychological factors such as depression, smoking, drinking, water and sodium restrictions, exercise, and adherence in patients with chronic heart failure following cardiac resynchronization therapy. METHODS: This cross-sectional study was conducted using the Morisky Medication Adherence Scale, Minnesota Living With Heart Failure Questionnaire, and Cardiac Depression Scale. A convenience sample of 141 patients with heart failure following cardiac resynchronization therapy were recruited from a tertiary academic hospital in Chengdu. RESULTS: The mean overall score of the Minnesota Living With Heart Failure Questionnaire was 30.89 (out of a total possible score of 105). Water restrictions, sodium restrictions, depression, and exercise were all shown to significantly predict quality of life among the participants. CONCLUSIONS / IMPLICATIONS FOR PRACTICE: This paper describes the quality of life and defines the behavioral factors that affect the quality of life of patients with heart failure following cardiac resynchronization therapy. The findings suggest that nurses should manage and conduct health education for patients in order to improve their quality of life.


Assuntos
Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca/psicologia , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Insuficiência Cardíaca/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto
18.
PLoS One ; 9(9): e98643, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25268604

RESUMO

It is inevitable that tree species will undergo considerable range shifts in response to anthropogenic induced climate change, even in the near future. Species Distribution Models (SDMs) are valuable tools in exploring general temporal trends and spatial patterns of potential range shifts. Understanding projections to future climate for tree species will facilitate policy making in forestry. Comparative studies for a large number of tree species require the availability of suitable and standardized indices. A crucial limitation when deriving such indices is the threshold problem in defining ranges, which has made interspecies comparison problematic until now. Here we propose a set of threshold-free indices, which measure range explosion (I), overlapping (O), and range center movement in three dimensions (Dx, Dy, Dz), based on fuzzy set theory (Fuzzy Set based Potential Range Shift Index, F-PRS Index). A graphical tool (PRS_Chart) was developed to visualize these indices. This technique was then applied to 46 Pinaceae species that are widely distributed and partly common in China. The spatial patterns of the modeling results were then statistically tested for significance. Results showed that range overlap was generally low; no trends in range size changes and longitudinal movements could be found, but northward and poleward movement trends were highly significant. Although range shifts seemed to exhibit huge interspecies variation, they were very consistent for certain climate change scenarios. Comparing the IPCC scenarios, we found that scenario A1B would lead to a larger extent of range shifts (less overlapping and more latitudinal movement) than the A2 and the B1 scenarios. It is expected that the newly developed standardized indices and the respective graphical tool will facilitate studies on PRS's for other tree species groups that are important in forestry as well, and thus support climate adaptive forest management.


Assuntos
Modelos Estatísticos , Dispersão Vegetal/fisiologia , Traqueófitas/fisiologia , Árvores/fisiologia , China , Mudança Climática , Agricultura Florestal/estatística & dados numéricos , Especificidade da Espécie
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