49 research outputs found
Pyrolysis gas as a carbon source for biogas production via anaerobic digestion
Carbon is an important resource for anaerobes to enhance biogas production. In this study, the possibility of using simulated pyrolysis gas (SPG) as a carbon source for biogas production was investigated. The effects of stirring speed (SS), gas holding time (GHT), and H2 addition on biomethanation of SPG were evaluated. The diversity and structure of microbial communities were also analyzed under an illumina MiSeq platform. Results indicated that at a GHT of 14 h and an SS at 400 rpm, SPG with up to 64.7% CH4could be bio-upgraded to biogas. Gasāliquid mass transfer is the limitation for SPG biomethanation. For the first time, it has been noticed that the addition of H2 can bioupgrade SPG to high quality biogas (with 91.1% CH4). Methanobacterium was considered as a key factor in all reactors. This study provides an idea and alternative way to convert lignocellulosic biomass and solid organic waste into energy (e.g., pyrolysis was used as a pretreatment to produce pyrolysis gas from biomass, and then, pyrolysis gas was bioupgraded to higher quality biogas via anaerobic digestion)
Facile preparation of high-performance Fe-doped CeāMn/TiO2 catalysts for the low-temperature selective catalytic reduction of NOx with NH3ā
A CeāMnāFe/TiO2 catalyst has been successfully prepared using a single impregnation method, and excellent low-temperature NH3-SCR activity was demonstrated in comparison with other typical SCR catalysts including MnāCe/TiO2 and metal-doped MnāCe/TiO2. The crystal structure, morphology, textural properties, valence state of the metals, acidity and redox properties of the novel catalyst were investigated comprehensively by X-ray diffraction (XRD), N2 adsorption and desorption analysis, X-ray photoelectron spectroscopy (XPS), NH3-temperature-programmed desorption (NH3-TPD), and H2-temperature-programmed reduction (H2-TPR). The Fe-doped CeāMn/TiO2 catalyst boosted the low-temperature NH3-SCR activity effectively under a broad temperature range (100ā280 Ā°C) with a superior NO conversion rate at low temperatures (100 Ā°C, 96%; 120ā160 Ā°C, ā¼100%). Fe doping caused this improvement by enlarging the catalyst pore volume, improving the redox properties, and increasing the amount of acidic sites. These properties enhanced the ability of the catalyst to adsorb NH3 and improved the low-temperature SCR performance, especially at temperatures lower than 150 Ā°C. Moreover, redox cycles of Ce, Mn, and Ti (Mn4+ + Ce3+ ā Mn3+ + Ce4+, Mn4+ + Ti3+ ā Mn3+ + Ti4+) also played an important role in enhancing the low-temperature SCR efficiency by accelerating the electron transfer. The excellent NH3-SCR result is promising for developing environmentally-friendly and more effective industrial catalysts in the future
Role of 18F-MD-PSMA PET/CT in initial stage of intermediate and high risk prostate cancer
ObjectiveĀ·To evaluate the role of 18F-MD-PSMA PET/CT in the initial stage of patients with moderate and high risk prostate cancer (PCa).MethodsĀ·A total of 67 patients with moderate and high risk PCa who were treated in Xinhua Hospital, Shanghai Jiao Tong University School of Medicine from September 2017 to June 2022 were initially staged by 18F-MD-PSMA PET/CT. Conventional imaging (CI), including multi-parameter magnetic resonance imaging (mp-MRI) and bone scintigraphy (BS), were performed within two weeks before 18F-MD-PSMA PET/CT. Twenty-five patients underwent 18F-FDG PET/CT at the same time. The sensitivity (SEN), specificity (SPEC), positive predictive value (PPV), negative predictive value (NPV) and accuracy (ACU) of 18F-MD-PSMA PET/CT in the initial stage were evaluated, and the results were compared with those of 18F-FDG PET/CT, mp-MRI and BS. The consistency of 18F-MD-PSMA PET/CT and CI in terms of primary lesion, regional lymph node metastasis and bone metastasis was evaluated by Kappa consistency test refering to the postoperative pathological T and N staging results and bone metastasis results of clinical follow-up. Kappa coefficient was calculated and compared.ResultsĀ·Of the 67 patients with PCa, 38 patients underwent radical prostatectomy and had completed pathological data, with 27 patients undergoing regional lymphadenectomy and 1 patient undergoing expanded pelvic lymphadenectomy at the same time. The pathological results were obtained as gold standard. The detection rates of mp-MRI and 18F-MD-PSMA PET/CT in diagnosing intrathecal lesions were both 100%. The SENs in diagnosing bilateral intralobular lesions were 26.3% and 63.2%, respctively; the SPECs were both 75.0%.The Kappa consistency test showed that the consistency of 18F-MD-PSMA PET/CT in diagnosis of extracapsular extension (EPE), seminal vesicle invasion (SVI), and bladder neck invasion (BNI) was higher than that of mp-MRI. Fisherā²s exact test showed that there were no statistically significant differences in SEN (P=0.226, P=0.491) and SPEC (P=1.000, P=0.342) between the two methods for diagnosing EPE and SVI, as well as SEN (P=1.000) for diagnosing BNI. In terms of diagnosis of lymph node metastasis, based on the analysis of lymph node numbers, the consistency between 18F-MD-PSMA PET/CT and pathological results was higher than that of mp-MRI (Kappa coefficients of 0.555 and 0.137, respectively). Fisherā²s exact test showed that there were no statistically significant differences in SEN and SPEC between the two examination methods (P=0.562, P=0.829). Based on the patients, the consistency between 18F-MD-PSMA PET/CT and pathological results was higher than that of mp-MRI (Kappa coefficients of 0.850 and 0.313, respectively). There was no statistically significant difference in SEN between the two methods (P=1.000). In terms of diagnosis of bone metastasis, based on the analysis of bone lesion numbers, the consistency between 18F-MD-PSMA PET/CT and clinical follow-up results was higher than that of BS (Kappa coefficients of 0.500 and 0.299, respectively). Fisherā²s exact test showed that there was no statistically significant difference in SEN between the two methods (P=0.219). Based on the patients, the consistency between 18F-MD-PSMA PET/CT and clinical follow-up results was higher than that of BS (Kappa coefficients of 0.953 and 0.766, respectively). There was no statistically significant difference in SEN between the two methods (P=1.000). The risks of 21 patients (31.3%) were increased after 18F-MD-PSMA PET/CT detection, with 1 patient (1.5%) decreasing. The initial stage of 32 cases (47.8%) were changed after 18F-MD-PSMA PET/CT detection, with 27 cases (40.3%) upstaged and 5 cases (7.5%) downstaged.ConclusionĀ·18F-MD-PSMA PET/CT is superior to CI in the diagnosis of bilateral intralobular lesions, EPE, SVI, regional lymph node metastasis and bone metastasis in intermediate and high risk PCa, and on this basis, the diagnosis of clinical stage and metastatic status of some patients has been changed
Photoluminescence mechanism and applications of Zn-doped carbon dots
Heteroatom-doped carbon dots (CDs) with excellent optical characteristics and negligible toxicity have emerged in many applications including bioimaging, biosensing, photocatalysis, and photothermal therapy. The metal-doping of CDs using various heteroatoms results in an enhancement of the photophysics but also imparts them with multifunctionality. However, unlike nonmetal doping, typical metal doping results in low fluorescence quantum yields (QYs), and an unclear photoluminescence mechanism. In this contribution, we detail results concerning zinc doped CDs (Zn-CDs) with QYs of up to 35%. The zinc ion charges serve as a surface passivating agent and prevent the aggregation of graphene pāp stacking, leading to an increase in the QY of the Zn-CDs. Structural and chemical investigations using spectroscopic and first principle simulations further revealed the effects of zinc doping on the CDs. The robust Zn-CDs were used for the ultra-trace detection of Hg2+ with a detection limit of 0.1 mM, and a quench mechanism was proposed. The unique optical properties of the Zn-CDs have promise for use in applications such as in vivo sensing and future phototherapy applications
Two Low-Complexity Efficient Beamformers for an IRS- and UAV-Aided Directional Modulation Network
As excellent tools for aiding communication, an intelligent reflecting surface (IRS) and an unmanned aerial vehicle (UAV) can extend the coverage area, remove the blind area, and achieve a dramatic rate improvement. In this paper, we improve the secrecy rate (SR) performance of directional modulation (DM) networks using an IRS and UAV in combination. To fully explore the benefits of the IRS and UAV, two efficient methods are proposed to enhance the SR performance. The first approach computes the confidential message (CM) beamforming vector by maximizing the SR, and the signal-to-leakage-noise ratio (SLNR) method is used to optimize the IRS phase shift matrix (PSM), which is called Max-SR-SLNR. To reduce the computational complexity, the CM, artificial noise (AN) beamforming, and IRS phase shift design are independently designed in the following method. The CM beamforming vector is constructed based on the maximum ratio transmission (MRT) criteria along the channel from Alice-to-IRS, the AN beamforming vector is designed by null-space projection (NSP) on the remaining two channels, and the PSM of the IRS is directly given by the phase alignment (PA) method. This method is called the MRT-NSP-PA. The simulation results show that the SR performance of the Max-SR-SLNR method outperforms the MRT-NSP-PA method in the cases of small-scale and medium-scale IRSs, and the latter approaches the former in performance as the IRS tends to a larger scale
An Effective Data Transmission Algorithm Based on Social Relationships in Opportunistic Mobile Social Networks
With the popularization of mobile communication equipment, human activities have an increasing impact on the structure of networks, and so the social characteristics of opportunistic networks become increasingly obvious. Opportunistic networks are increasingly used in social situations. However, existing routing algorithms are not suitable for opportunistic social networks, because traditional opportunistic network routing does not consider participation in human activities, which usually causes a high ratio of transmission delay and routing overhead. Therefore, this research proposes an effective data transmission algorithm based on social relationships (ESR), which considers the community characteristics of opportunistic mobile social networks. This work uses the idea of the faction to divide the nodes in the network into communities, reduces the number of inefficient nodes in the community, and performs another contraction of the structure. Simulation results show that the ESR algorithm, through community transmission, is not only faster and safer, but also has lower transmission delay and routing overhead compared with the spray and wait algorithm, SCR algorithm and the EMIST algorithm
Genome-Wide Identification of SPX Family Genes and Functional Characterization of <i>PeSPX6</i> and <i>PeSPX-MFS2</i> in Response to Low Phosphorus in <i>Phyllostachys edulis</i>
Moso bamboo (Phyllostachys edulis) is the most widely distributed bamboo species in the subtropical regions of China. Due to the fast-growing characteristics of P. edulis, its growth requires high nutrients, including phosphorus. Previous studies have shown that SPX proteins play key roles in phosphorus signaling and homeostasis. However, the systematic identification, molecular characterization, and functional characterization of the SPX gene family have rarely been reported in P. edulis. In this study, 23 SPXs were identified and phylogenetic analysis showed that they were classified into three groups and distributed on 13 chromosomes. The analysis of conserved domains indicated that there was a high similarity between PeSPXs among SPX proteins in other species. RNA sequencing and qRT-PCR analysis indicated that PeSPX6 and PeSPX-MFS2, which were highly expressed in roots, were clearly upregulated under low phosphorus. Co-expression network analysis and a dual luciferase experiment in tobacco showed that PeWRKY6 positively regulated the PeSPX6 expression, while PeCIGR1-2, PeMYB20, PeWRKY6, and PeWRKY53 positively regulated the PeSPX-MFS2 expression. Overall, these results provide a basis for the identification of SPX genes in P. edulis and further exploration of their functions in mediating low phosphorus responses
A Universal Routing Algorithm Based on Intuitionistic Fuzzy Multi-Attribute Decision-Making in Opportunistic Social Networks
With the vigorous development of big data and the 5G era, in the process of communication, the number of information that needs to be forwarded is increasing. The traditional end-to-end communication mode has long been unable to meet the communication needs of modern people. Therefore, it is particularly important to improve the success rate of information forwarding under limited network resources. One method to improve the success rate of information forwarding in opportunistic social networks is to select appropriate relay nodes so as to reduce the number of hops and save network resources. However, the existing routing algorithms only consider how to select a more suitable relay node, but do not exclude untrusted nodes before choosing a suitable relay node. To select a more suitable relay node under the premise of saving network resources, a routing algorithm based on intuitionistic fuzzy decision-making model is proposed. By analyzing the real social scene, the algorithm innovatively proposes two universal measurement indexes of node attributes and quantifies the support degree and opposition degree of node social attributes to help node forward by constructing intuitionistic fuzzy decision-making matrix. The relay nodes are determined more accurately by using the multi-attribute decision-making method. Simulation results show that, in the best case, the forwarding success rate of IFMD algorithm is 0.93, and the average end-to-end delay, network load, and energy consumption are the lowest compared with Epidemic algorithm, Spray and Wait algorithm, NSFRE algorithm, and FCNS algorithm
A Comprehensive Multi-Scenario Routing Algorithm Based on Fuzzy Control Theory in Opportunistic Social Network
With the flourishing of big data and the 5G era, the amount of data to be transmitted in the communication process is increasing, and end-to-end communication in traditional social networks has been unable to meet the current communication needs. Therefore, in order to improve the success rate of data forwarding, social networks propose that the sender of the message should reasonably choose the next hop node. However, existing routing and forwarding algorithms do not take into account nodes that are live in different scenarios, and the applicable next hop node metrics are also different. These algorithms only consider the forwarding preferences of the nodes during working hours and do not consider the forwarding preferences of the nodes during non-working hours. We propose a routing algorithm based on fuzzy decision theory, which aims at a more accurate decision on selecting the next hop. A routing and forwarding algorithm based on fuzzy decision is proposed in this paper. This algorithm symmetrical divides scenes in opportunistic social networks into working time and non-working time according to real human activity. In addition, metrics are designed symmetrically for these two scenarios. Simulation results demonstrate that, in the best case, the proposed scheme presents an average delivery ratio of 0.95 and reduces the average end-to-end delay and average overhead compared with the epidemic routing algorithm, the EIMSTalgorithm, the ICMT algorithm, and the FCNSalgorithm
Case Report: A Synonymous Mutation in NF1 Located at the Non-canonical Splicing Site Leading to Exon 45 Skipping
Synonymous mutations are generally considered non-pathogenic because it did not alter the amino acids of the encoded protein. Publications of the associations between synonymous mutations and abnormal splicing have increased recently, however, not much observations available described the synonymous mutations at the non-canonical splicing sites leading to abnormal splicing. In this pedigree, the proband was diagnosed Neurofibromatosis type I due to the presence of typical cafeā au lait macules and pectus carinatum. Whole-exome sequencing identified a synonymous mutation c.6795C > T (p.N2265N) of the NF1 gene which was located at the non-canonical splicing sites. Reverse transcription polymerase chain reaction followed by Sanger sequencing was carried out, and the skipping of exon 45 was observed. Therefore, the pathogenicity of the synonymous mutation c.6795C > T was confirmed. Our finding expanded the spectrum of pathogenic mutations in Neurofibromatosis type I and provided information for genetic counseling