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1.
Plant Mol Biol ; 114(3): 40, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622367

RESUMO

Parasitic lifestyle can often relax the constraint on the plastome, leading to gene pseudogenization and loss, and resulting in diverse genomic structures and rampant genome degradation. Although several plastomes of parasitic Cuscuta have  been reported, the evolution of parasitism in the family Convolvulaceae which is linked to structural variations and reduction of plastome has not been well investigated. In this study, we assembled and collected 40 plastid genomes belonging to 23 species representing four subgenera of Cuscuta and ten species of autotrophic Convolvulaceae. Our findings revealed nine types of structural variations and six types of inverted repeat (IR) boundary variations in the plastome of Convolvulaceae spp. These structural variations were associated with the shift of parasitic lifestyle, and IR boundary shift, as well as the abundance of long repeats. Overall, the degradation of Cuscuta plastome proceeded gradually, with one clade exhibiting an accelerated degradation rate. We observed five stages of gene loss in Cuscuta, including NAD(P)H complex → PEP complex → Photosynthesis-related → Ribosomal protein subunits → ATP synthase complex. Based on our results, we speculated that the shift of parasitic lifestyle in early divergent time promoted relaxed selection on plastomes, leading to the accumulation of microvariations, which ultimately resulted in the plastome reduction. This study provides new evidence towards a better understanding of plastomic evolution, variation, and reduction in the genus Cuscuta.


Assuntos
Convolvulaceae , Cuscuta , Genomas de Plastídeos , Convolvulaceae/genética , Cuscuta/genética , Genes de Plantas , Fotossíntese/genética , Filogenia , Evolução Molecular
2.
Int Wound J ; 21(4): e14855, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38562093

RESUMO

To explore the role of nutritional support in nursing practice on postoperative surgical site wound healing in patients undergoing surgery at risk for pressure ulcers. This study adopted a retrospective experimental design and included a total of 60 patients at risk of pressure ulcers, divided into a nutritional support group and a control group, with 30 people in each group. The nutritional support group implemented specific nutritional support measures after surgery, while the control group received standard postoperative care. Outcome measures included redness and swelling scores, edema scores, anxiety assessments, pain scores, bleeding volume, recovery time and incidence of pressure ulcers. The result indicates that patients who received nutritional support exhibited lower postoperative wound redness and swelling scores compared to the control group (3.11 ± 0.45 vs. 4.85 ± 0.74, p < 0.05). Additionally, the nutritional support group showed significantly lower edema scores (2.75 ± 0.37 vs. 3.53 ± 0.62, p < 0.05). Anxiety levels, as measured by the anxiety assessment scale (SAS), were also lower in the nutritional support group (6.52 ± 1.19 vs. 7.60 ± 1.62, p < 0.05). Moreover, the average healing time was shorter for the nutritional support group (7.27 ± 1.36 days) compared to the control group (9.71 ± 1.84 days, p < 0.05). Postoperative pain scores were lower in the nutritional support group (4.13 ± 0.72 vs. 5.43 ± 0.62, p < 0.05), and patient satisfaction scores were higher (9.42 ± 0.76 vs. 7.25 ± 0.81, p < 0.05). Nutritional support has a positive effect on postoperative wound healing at surgical sites in patients at risk of pressure ulcers in nursing practice. It can significantly reduce redness, swelling, edema, anxiety, and pain scores, reduce bleeding, shorten recovery time, and reduce pressure ulcers. incidence rate.


Assuntos
Úlcera por Pressão , Humanos , Estudos Retrospectivos , Úlcera por Pressão/etiologia , Úlcera por Pressão/prevenção & controle , Apoio Nutricional , Cicatrização , Dor , Edema
3.
World J Microbiol Biotechnol ; 39(8): 204, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37209190

RESUMO

Many bioactive secondary metabolites synthesized by fungi have important applications in many fields, such as agriculture, food, medical and others. The biosynthesis of secondary metabolites is a complex process involving a variety of enzymes and transcription factors, which are regulated at different levels. In this review, we describe our current understanding on molecular regulation of fungal secondary metabolite biosynthesis, such as environmental signal regulation, transcriptional regulation and epigenetic regulation. The effects of transcription factors on the secondary metabolites produced by fungi were mainly introduced. It was also discussed that new secondary metabolites could be found in fungi and the production of secondary metabolites could be improved. We also highlight the importance of understanding the molecular regulation mechanisms to activate silent secondary metabolites and uncover their physiological and ecological functions. By comprehensively understanding the regulatory mechanisms involved in secondary metabolite biosynthesis, we can develop strategies to improve the production of these compounds and maximize their potential benefits.


Assuntos
Epigênese Genética , Fungos , Metabolismo Secundário , Fungos/genética , Fungos/metabolismo , Regulação Fúngica da Expressão Gênica , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
4.
Entropy (Basel) ; 25(3)2023 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36981311

RESUMO

Link prediction is a hot issue in information filtering. Link prediction algorithms, based on local similarity indices, are widely used in many fields due to their high efficiency and high prediction accuracy. However, most existing link prediction algorithms are available for unweighted networks, and there are relatively few studies for weighted networks. In the previous studies on weighted networks, some scholars pointed out that links with small weights play a more important role in link prediction and emphasized that weak-ties theory has a significant impact on prediction accuracy. On this basis, we studied the edges with different weights, and we discovered that, for edges with large weights, this weak-ties theory actually does not work; Instead, the weak-ties theory works in the prediction of edges with small weights. Our discovery has instructive implications for link predictions in weighted networks.

5.
Entropy (Basel) ; 26(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38275487

RESUMO

Malicious attacks can cause significant damage to the structure and functionality of complex networks. Previous research has pointed out that the ability of networks to withstand malicious attacks becomes weaker when networks are coupled. However, traditional research on improving the robustness of networks has focused on individual low-order or higher-order networks, lacking studies on coupled networks with higher-order and low-order networks. This paper proposes a method for optimizing the robustness of coupled networks with higher-order and low-order based on a simulated annealing algorithm to address this issue. Without altering the network's degree distribution, the method rewires the edges, taking the robustness of low-order and higher-order networks as joint optimization objectives. Making minimal changes to the network, the method effectively enhances the robustness of coupled networks. Experiments were conducted on Erdos-Rényi random networks (ER), scale-free networks (BA), and small-world networks (SW). Finally, validation was performed on various real networks. The results indicate that this method can effectively enhance the robustness of coupled networks with higher-order and low-order.

6.
Plant Cell Rep ; 41(5): 1243-1260, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35325290

RESUMO

KEY MESSAGE: Jasmonate induced FaTPS1 to produce terpene, and overexpression FaTPS1 led to fruit resistant against B. cinerea infection, FaMYC2 induced FaTPS1 by binding to its promoter that downstream of jasmonate. Jasmonic acid (JA) and its derivatives are associated with plant defence responses against pathogenic organisms. In the present study, a total of 10,631 differentially expressed genes, 239 differentially expressed proteins, and 229 differential metabolites were screened and found to be mainly involved in pathogen perception, hormone biosynthesis and signal transduction, photosynthesis, and secondary metabolism. In strawberry fruits, methyl jasmonate (MeJA) induced FaTPS1 expression and quickly increased the terpene content. Furthermore, FaTPS1 overexpression increased the emission of sesquiterpenes, especially germacrene D, and improved strawberry resistance against Botrytis cinerea infection, although the knockdown of FaTPS1 increased its susceptibility to the same pathogen. Using a yeast one-hybrid assay and transient expression analysis, we demonstrated that FaMYC2 can bind to the G-box element in the promoter region of FaTPS1, thus inducing FaTPS1 expression. MeJA also stimulated FaMYC2 expression and regulated downstream signalling cascades. Moreover, we presented a possible model of the new signalling pathway of MeJA-mediated strawberry resistance to B. cinerea.


Assuntos
Fragaria , Alquil e Aril Transferases , Botrytis/fisiologia , Ciclopentanos/metabolismo , Ciclopentanos/farmacologia , Resistência à Doença/genética , Fragaria/genética , Fragaria/metabolismo , Regulação da Expressão Gênica de Plantas , Oxilipinas/metabolismo , Oxilipinas/farmacologia , Doenças das Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Terpenos/farmacologia
7.
BMC Biol ; 19(1): 232, 2021 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-34711223

RESUMO

BACKGROUND: Flowering plants (angiosperms) are dominant components of global terrestrial ecosystems, but phylogenetic relationships at the familial level and above remain only partially resolved, greatly impeding our full understanding of their evolution and early diversification. The plastome, typically mapped as a circular genome, has been the most important molecular data source for plant phylogeny reconstruction for decades. RESULTS: Here, we assembled by far the largest plastid dataset of angiosperms, composed of 80 genes from 4792 plastomes of 4660 species in 2024 genera representing all currently recognized families. Our phylogenetic tree (PPA II) is essentially congruent with those of previous plastid phylogenomic analyses but generally provides greater clade support. In the PPA II tree, 75% of nodes at or above the ordinal level and 78% at or above the familial level were resolved with high bootstrap support (BP ≥ 90). We obtained strong support for many interordinal and interfamilial relationships that were poorly resolved previously within the core eudicots, such as Dilleniales, Saxifragales, and Vitales being resolved as successive sisters to the remaining rosids, and Santalales, Berberidopsidales, and Caryophyllales as successive sisters to the asterids. However, the placement of magnoliids, although resolved as sister to all other Mesangiospermae, is not well supported and disagrees with topologies inferred from nuclear data. Relationships among the five major clades of Mesangiospermae remain intractable despite increased sampling, probably due to an ancient rapid radiation. CONCLUSIONS: We provide the most comprehensive dataset of plastomes to date and a well-resolved phylogenetic tree, which together provide a strong foundation for future evolutionary studies of flowering plants.


Assuntos
Magnoliopsida , Núcleo Celular , Ecossistema , Humanos , Magnoliopsida/genética , Filogenia , Plastídeos
8.
Entropy (Basel) ; 24(8)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-36010708

RESUMO

In this paper, we propose a novel multi-user access in wireless optical communication based on the quantum detection of the coherent state. In this case, the coherent states are used as the signal carrier and a technique of quantum detection is applied to distinguish between signals from different users. To accomplish this task, two main quantum measurement methods are introduced; one is minimum error discrimination (MED), and the other is unambiguous state discrimination (USD). The theoretical derivation implies that the two methods can both distinguish between the signals from different users efficiently when the average photon number is large enough. Typically, the numerical result shows that in the two-user case, the channel capacity will approach the theoretical maximum limit when the average photon number is greater than 2.5 for MED and 5 for USD in the absence of noise. The MED gains more channel capacity than the USD at the same average photon number. However, the USD wins the error-correction scene with its free-error capability. Furthermore, the detection error probability and channel capacity for the USD with the thermal noise are examined. The result shows that increasing the signal average photon number can continue the USD's advantage of error-free detection even if in the presence of thermal noise. In addition, compared with non-orthogonal multiple access (NOMA), the bit error rate (BER) against signal-to-noise rate (SNR) performance of USD has been improved.

9.
Entropy (Basel) ; 25(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36673163

RESUMO

The higher-order structure of networks is a hot research topic in complex networks. It has received much attention because it is closely related to the functionality of networks, such as network transportation and propagation. For instance, recent studies have revealed that studying higher-order networks can explore hub structures in transportation networks and information dissemination units in neuronal networks. Therefore, the destruction of the connectivity of higher-order networks will cause significant damage to network functionalities. Meanwhile, previous works pointed out that the function of a complex network depends on the giant component of the original(low-order) network. Therefore, the network functionality will be influenced by both the low-order and its corresponding higher-order network. To study this issue, we build a network model of the interdependence of low-order and higher-order networks (we call it ILH). When some low-order network nodes fail, the low-order network's giant component shrinks, leading to changes in the structure of the higher-order network, which further affects the low-order network. This process occurs iteratively; the propagation of the failure can lead to an eventual network crash. We conducted experiments on different networks based on the percolation theory, and our network percolation results demonstrated a first-order phase transition feature. In particular, we found that an ILH is more fragile than the low-order network alone, and an ILH is more likely to be corrupted in the event of a random node failure.

10.
J Minim Access Surg ; 18(1): 31-37, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33047683

RESUMO

BACKGROUND: Intracorporeal oesophagojejunostomy is one of the key steps in laparoscopic total gastrectomy (LTG). At present, there is no widely accepted anastomosis technique in oesophagojejunostomy. MATERIALS AND METHODS: We retrospectively studied 63 patients with gastric cancer who underwent LTG. Two types of anastomosis techniques have been applied during LTG: the reverse puncture device (RPD) (28 patients) and overlap (35 patients). RESULTS: A total of 63 patients (51 males and 12 females: mean age = 58 years and mean body mass index [BMI] = 26.3 kg/m2) were enrolled in this study. There were no significant difference in age, BMI, duration of surgery, duration of anastomosis, blood loss, post-operative hospital stay, tumour location, tumour size, degree of tumour differentiation, Borrmann type, total number of lymph nodes, number of positive lymph nodes, hospital stay, hospitalisation costs, intra-operative complications, post-operative complications and prognosis between the RPD group and the overlap group. RPD group showed a significant advantage in terms of the distance between the top border of tumours and the top resection margin (P < 0.001). We further found that the oesophageal lateral negative surgical margin distance of the upper gastric cancer in the RPD group was significantly longer than that in the overlap group (P < 0.001). CONCLUSIONS: Both the RPD and overlap techniques are safe and applicable in LTG. However, RPD has the advantage of obtaining an adequate safe margin compared with that of overlap technique, especially in patients with gastro-oesophageal junction carcinoma.

11.
Plant Cell Physiol ; 62(6): 971-984, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34046678

RESUMO

The plastid genome (plastome) is highly conserved in both gene order and content and has a lower mutation rate than the nuclear genome. However, the plastome is more variable in heterotrophic plants. To date, most such studies have investigated just a few species or only holoheterotrophic groups, and few have examined plastome evolution in recently derived lineages at an early stage of transition from autotrophy to heterotrophy. In this study, we investigated the evolutionary dynamics of plastomes in the monophyletic and recently derived Pedicularis sect. Cyathophora (Orobanchaceae). We obtained 22 new plastomes, 13 from the six recognized species of section Cyathophora, six from hemiparasitic relatives and three from autotrophic relatives. Comparative analyses of gene content, plastome structure and selection pressure showed dramatic differences among species in section Cyathophora and in Pedicularis as a whole. In comparison with autotrophic relatives and other Pedicularis spp., we found that the inverted repeat (IR) region in section Cyathophora had expansions to the small single-copy region, with a large expansion event and two independent contraction events. Moreover, NA(D)H dehydrogenase, accD and ccsA have lost function multiple times, with the function of accD being replaced by nuclear copies of an accD-like gene in Pedicularis spp. The ccsA and ndhG genes may have evolved under selection in association with IR expansion/contraction events. This study is the first to report high plastome variation in a recently derived lineage of hemiparasitic plants and therefore provides evidence for plastome evolution in the transition from autotrophy to heterotrophy.


Assuntos
Genomas de Plastídeos , Pedicularis/genética , Filogenia , Plastídeos/genética , Evolução Molecular , Genes de Plantas , NADH Desidrogenase/genética , Pseudogenes
12.
BMC Surg ; 21(1): 329, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34407789

RESUMO

BACKGROUND: Mediastinal lymph node metastases (MLNM) are not rare in thyroid cancer, but their treatment has not been extensively studied. This study aimed to explore the preliminary application of video mediastinoscopy-assisted superior mediastinal dissection in the diagnosis and treatment of thyroid carcinoma with mediastinal lymphadenopathy. MATERIALS AND METHODS: We retrospectively reviewed the clinical pathologic data and short-term outcomes of thyroid cancer patients with suspicious MLNM treated with video mediastinoscopy-assisted mediastinal dissection at our institution from 2017 to 2020. RESULTS: Nineteen patients were included: 14 with medullary thyroid carcinoma and five with papillary thyroid carcinoma. Superior mediastinal nodes were positive in nine (64.3%) patients with medullary thyroid carcinoma and in four (80.0%) patients with papillary carcinoma. No fatal bleeding occurred. There were three cases of temporary recurrent laryngeal nerve (RLN) palsy postoperatively, one of which was bilateral. Four patients had temporary hypocalcemia requiring supplementation, one had a chyle fistula, and one developed wound infection after the procedure. Postoperative serum molecular markers decreased in all patients. One patient died of cancer while the other 18 patients remained disease-free, with a median follow-up of 33 months. CONCLUSION: Video mediastinoscopy-assisted superior mediastinal dissection can be performed relatively safely in patients with suspicious MLNM. This diagnostic and therapeutic approach may help control locoregional recurrences.


Assuntos
Linfadenopatia , Neoplasias da Glândula Tireoide , Dissecação , Humanos , Excisão de Linfonodo , Linfonodos/patologia , Mediastinoscopia , Esvaziamento Cervical , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia
13.
J Minim Access Surg ; 16(2): 138-143, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30777995

RESUMO

Objective: Lymph node metastasis (LNM) is one of the important prognostic factors of early gastric cancer (EGC). Moreover, LNM is also important when choosing therapeutic intervention for EGC patients. The purpose of this study is to explore the risk factors of LNM in EGC and to discuss the corresponding treatment. Design: We retrospectively reviewed the medical records of 253 patients with EGC who underwent surgical therapy in our department between 2012 and 2015. Univariate analysis and Multivariate Cox regression were used to evaluate the independent risk factors of LNM. Results: LNM was present in 38 cases among 253 patients (15%). Univariate analysis showed an obvious correlation between LNM and tumour location, tumour size, depth of invasion, morphological classification, gross type of the lesion and venous invasion. Multivariate analysis indicated that poorly differentiated carcinoma, submucosal cancer, tumour size ≥2 cm and venous invasion were the independent risk factors for LNM. Conclusion: Tumour size, depth of invasion, morphological classification and blood vessel invasion were predictive risk factors for LNM in EGC. We propose that EGC patients with those risk factors should be accepted gastrectomy with LN dissection.

14.
J Minim Access Surg ; 16(1): 41-46, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30106026

RESUMO

INTRODUCTION: At present, the main treatment of gastric cancer is surgical resection combined with radiotherapy and chemotherapy, the most important part of which is radical gastrectomy. Laparoscopic radical gastrectomy for advanced gastric cancer is difficult to operate, and whether it can achieve the same curative effect with the laparotomy is still controversial. MATERIALS AND METHODS: This study retrospectively analysed the clinical data of 269 gastric cancer patients surgically treated by our medical team from May 2011 to December 2015 for comparative analysis of the clinical efficacy of laparoscopic-assisted radical gastrectomy and traditional open radical gastrectomy. RESULTS: The laparoscopic surgery group had longer duration of surgery, less intra-operative blood loss, shorter post-operative exhaust time, shorter post-operative hospital stay and shorter timing of drain removal. The average number of harvested lymph nodes in the laparoscopic surgery group was 22.9 ± 9.5 per case. And in the laparotomy group the average number was 23.3 ± 9.9 per case. The difference had no statistical significance. With the increase of the number of laparoscopic surgical procedures, the amount of intra-operative blood loss gradually decreases, and the duration of surgery is gradually reduced. CONCLUSION: Laparoscopic radical gastrectomy is superior to open surgery in the aspects of intra-operative blood loss, post-operative exhaust time, post-operative hospital stay and timing of drain removal. With the number of laparoscopic radical gastrectomy cases increased, the duration of surgery is shortened and the amount of intra-operative blood loss will decrease.

16.
Appl Opt ; 58(18): 5107-5114, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31503832

RESUMO

The operational reliability directly affects the practical application of optical current transformers (OCTs) in smart substations. As the key component of the OCT, the reliability of the optical current sensor (OCS) largely determines the reliability level of the OCT. This paper proposes a reliability assessment method of the OCS based on accelerated aging tests. The failure modes and failure mechanisms of the OCS are analyzed, and the concept of OCS insertion loss variation is proposed. An allowable range of insertion loss variation is selected as the failure criterion of the OCS. From the viewpoint of the OCS measurement error generated by the quantization error of the analog-to-digital converter, the allowable range of insertion loss variation is obtained. By selecting a high temperature as the accelerated thermal stress, we design the accelerated aging test scheme of the OCS and analyze the sample test data to obtain the activation energy of the OCS insertion loss failure. Based on this activation energy, the median time to failure and instantaneous failure rate curve of the OCS at normal temperature are obtained. The results indicate that the designed OCS has an expected service life of 50 years and a low instantaneous failure rate at normal temperature. This paper provides basic critical reliability analysis data for the system reliability assessment of OCTs.

17.
Sensors (Basel) ; 19(9)2019 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-31035606

RESUMO

A distributed single-input multiple-output (SIMO) sonar system is composed of a sound source and multiple underwater receivers. It provides an important framework for underwater target localization. However, underwater hostile environments bring more challenges for underwater target localization than terrestrial target localization, such as the difficulties of synchronizing all the underwater receiver clocks, the varying underwater sound speed and the uncertainties of the locations of the underwater receivers. In this paper, we take the sound speed variation, the time synchronization and the uncertainties of the receiver locations into account, and propose the underwater target localization and synchronization (UTLS) algorithm for the distributed SIMO sonar system. In the distributed SIMO sonar system, the receivers are organized in a star topology, where the information fusion is carried out in the central receiver (CR). All the receivers are not synchronized and their positions are known with uncertainties. Moreover, the underwater sound speed is approximately modeled by a depth-dependent sound speed profile (SSP). We evaluate our proposed UTLS algorithm by comparing it with several benchmark algorithms via numerical simulations. The simulation results reveal the superiority of our proposed UTLS algorithm.

18.
Sensors (Basel) ; 19(23)2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31766634

RESUMO

Accurate and reliable lightning current data are the basis of lightning protection design. To measure lightning current data at different measurement locations in a transmission system, the limitations of traditional lightning current sensors are analyzed, and optical current sensing technology is adopted, which has the advantages of no magnetic saturation and no bandwidth limitation. Compared with traditional application environments, the sensing technology is used in special environments in transmission systems. This paper analyzes the influence of environmental factors on sensors, and combines the extreme environmental requirements, such as temperature and insulation requirements, to study the sensor. Starting from the sensitivity, the sensing characteristics of the sensor are analyzed. The sensor is designed according to three aspects: sensing material selection, spatial measuring position, and sensing material size optimization, such that it can satisfy the different measurement requirements of towers, overhead ground wires, and transmission lines, respectively. The experiments indicate that the developed sensors can meet the measurement sensitivity requirements of different types of lightning strikes. The experimental results of sensors exhibit a reasonable amplitude measurement accuracy, linearity, and waveform measurement capability. These results provide important theoretical and experimental bases for the application of optical current sensing technology to the measurement of the lightning current of transmission systems.

19.
Sensors (Basel) ; 19(23)2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31757066

RESUMO

Today's sensor networks need robustness, security and efficiency with a high level of assurance. Error correction is an effective communicational technique that plays a critical role in maintaining robustness in informational transmission. The general way to tackle this problem is by using forward error correction (FEC) between two communication parties. However, by applying zero-error coding one can assure information fidelity while signals are transmitted in sensor networks. In this study, we investigate zero-error coding via both classical and quantum channels, which consist of n obfuscated symbols such as Shannon's zero-error communication. As a contrast to the standard classical zero-error coding, which has a computational complexity of , a general approach is proposed herein to find zero-error codewords in the case of quantum channel. This method is based on a n-symbol obfuscation model and the matrix's linear transformation, whose complexity dramatically decreases to . According to a comparison with classical zero-error coding, the quantum zero-error capacity of the proposed method has obvious advantages over its classical counterpart, as the zero-error capacity equals the rank of the quantum coefficient matrix. In particular, the channel capacity can reach n when the rank of coefficient matrix is full in the n-symbol multilateral obfuscation quantum channel, which cannot be reached in the classical case. Considering previous methods such as low density parity check code (LDPC), our work can provide a means of error-free communication through some typical channels. Especially in the quantum case, zero-error coding can reach both a high coding efficiency and large channel capacity, which can improve the robustness of communication in sensor networks.

20.
Sensors (Basel) ; 19(13)2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31284673

RESUMO

When applying an optical current transformer (OCT) to direct current measurement, output signals exhibit a low signal-to-noise ratio and signal-to-noise band overlap. Sinusoidal wave modulation is used to solve this problem. A double correlation detection algorithm is used to extract the direct current (DC) signal, remove white noise and improve the signal-to-noise ratio. Our sensing unit uses a terbium gallium garnet crystal in order to increase the output signal-to-noise ratio and measurement sensitivity. Measurement errors of single correlation and double correlation detection algorithms are compared, and experimental results showed that this measurement method can control measurement error to about 0.3%, thus verifying its feasibility.

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