Integrative Proteomic Characterization of Human Lung Adenocarcinoma.

Genomic studies of lung adenocarcinoma (LUAD) have advanced our understanding of the disease's biology and accelerated targeted therapy. However, the proteomic characteristics of LUAD remain poorly understood. We carried out a comprehensive proteomics analysis of 103 cases of LUAD in Chinese patients. Integrative analysis of proteome, phosphoproteome, transcriptome, and whole-exome sequencing data revealed cancer-associated characteristics, such as tumor-associated protein variants, distinct proteomics features, and clinical outcomes in patients at an early stage or with EGFR and TP53 mutations. Proteome-based stratification of LUAD revealed three subtypes (S-I, S-II, and S-III) related to different clinical and molecular features. Further, we nominated potential drug targets and validated the plasma protein level of HSP 90ß as a potential prognostic biomarker for LUAD in an independent cohort. Our integrative proteomics analysis enables a more comprehensive understanding of the molecular landscape of LUAD and offers an opportunity for more precise diagnosis and treatment.

Global disease burden of and risk factors for acute lower respiratory infections caused by respiratory syncytial virus in preterm infants and young children in 2019: a systematic review and meta-analysis of aggregated and individual participant data.

BACKGROUND: Infants and young children born prematurely are at high risk of severe acute lower respiratory infection (ALRI) caused by respiratory syncytial virus (RSV). In this study, we aimed to assess the global disease burden of and risk factors for RSV-associated ALRI in infants and young children born before 37 weeks of gestation. METHODS: We conducted a systematic review and meta-analysis of aggregated data from studies published between Jan 1, 1995, and Dec 31, 2021, identified from MEDLINE, Embase, and Global Health, and individual participant data shared by the Respiratory Virus Global Epidemiology Network on respiratory infectious diseases. We estimated RSV-associated ALRI incidence in community, hospital admission, in-hospital mortality, and overall mortality among children younger than 2 years born prematurely. We conducted two-stage random-effects meta-regression analyses accounting for chronological age groups, gestational age bands (early preterm, <32 weeks gestational age [wGA], and late preterm, 32 to <37 wGA), and changes over 5-year intervals from 2000 to 2019. Using individual participant data, we assessed perinatal, sociodemographic, and household factors, and underlying medical conditions for RSV-associated ALRI incidence, hospital admission, and three severity outcome groups (longer hospital stay [>4 days], use of supplemental oxygen and mechanical ventilation, or intensive care unit admission) by estimating pooled odds ratios (ORs) through a two-stage meta-analysis (multivariate logistic regression and random-effects meta-analysis). This study is registered with PROSPERO, CRD42021269742. FINDINGS: We included 47 studies from the literature and 17 studies with individual participant-level data contributed by the participating investigators. We estimated that, in 2019, 1 650 000 (95% uncertainty range [UR] 1 350 000-1 990 000) RSV-associated ALRI episodes, 533 000 (385 000-730 000) RSV-associated hospital admissions, 3050 (1080-8620) RSV-associated in-hospital deaths, and 26 760 (11 190-46 240) RSV-attributable deaths occurred in preterm infants worldwide. Among early preterm infants, the RSV-associated ALRI incidence rate and hospitalisation rate were significantly higher (rate ratio [RR] ranging from 1·69 to 3·87 across different age groups and outcomes) than for all infants born at any gestational age. In the second year of life, early preterm infants and young children had a similar incidence rate but still a significantly higher hospitalisation rate (RR 2·26 [95% UR 1·27-3·98]) compared with all infants and young children. Although late preterm infants had RSV-associated ALRI incidence rates similar to that of all infants younger than 1 year, they had higher RSV-associated ALRI hospitalisation rate in the first 6 months (RR 1·93 [1·11-3·26]). Overall, preterm infants accounted for 25% (95% UR 16-37) of RSV-associated ALRI hospitalisations in all infants of any gestational age. RSV-associated ALRI in-hospital case fatality ratio in preterm infants was similar to all infants. The factors identified to be associated with RSV-associated ALRI incidence were mainly perinatal and sociodemographic characteristics, and factors associated with severe outcomes from infection were mainly underlying medical conditions including congenital heart disease, tracheostomy, bronchopulmonary dysplasia, chronic lung disease, or Down syndrome (with ORs ranging from 1·40 to 4·23). INTERPRETATION: Preterm infants face a disproportionately high burden of RSV-associated disease, accounting for 25% of RSV hospitalisation burden. Early preterm infants have a substantial RSV hospitalisation burden persisting into the second year of life. Preventive products for RSV can have a substantial public health impact by preventing RSV-associated ALRI and severe outcomes from infection in preterm infants. FUNDING: EU Innovative Medicines Initiative Respiratory Syncytial Virus Consortium in Europe.

Genetic exchange with an outcrossing sister species causes severe genome-wide dysregulation in a selfing Caenorhabditis nematode.

Different modes of reproduction evolve rapidly, with important consequences for genome composition. Selfing species often occupy a similar niche as their outcrossing sister species with which they are able to mate and produce viable hybrid progeny, raising the question of how they maintain genomic identity. Here, we investigate this issue by using the nematode Caenorhabditis briggsae, which reproduces as a hermaphrodite, and its outcrossing sister species Caenorhabditis nigoni We hypothesize that selfing species might develop some barriers to prevent gene intrusions through gene regulation. We therefore examined gene regulation in the hybrid F2 embryos resulting from reciprocal backcrosses between F1 hybrid progeny and C. nigoni or C. briggsae F2 hybrid embryos with ∼75% of their genome derived from C. briggsae (termed as bB2) were inviable, whereas those with ∼75% of their genome derived from C. nigoni (termed as nB2) were viable. Misregulation of transposable elements, coding genes, and small regulatory RNAs was more widespread in the bB2 compared with the nB2 hybrids, which is a plausible explanation for the differential phenotypes between the two hybrids. Our results show that regulation of the C. briggsae genome is strongly affected by genetic exchanges with its outcrossing sister species, C. nigoni, whereas regulation of the C. nigoni genome is more robust on genetic exchange with C. briggsae The results provide new insights into how selfing species might maintain their identity despite genetic exchanges with closely related outcrossing species.

Oral administration of herbal oligonucleotide drug JGL-sRNA-h7 ameliorates hyperglycemia in db/db mice and beagle dogs.

Type 2 diabetes mellitus is a prevalent metabolic disease, posing a considerable threat to public health. Oligonucleotide drugs have proven to be a promising field of therapy for the diseases. In this study, we reported that a herbal small RNA (sRNA), JGL-sRNA-h7 (B34735529, F1439.L002444.A11), could exhibit potent hypoglycemic effects by targeting glucose-6-phosphatase. Oral administration of sphingosine (d18:1)-JGL-sRNA-h7 bencaosomes ameliorated hyperglycemia and diabetic kidney injury better than metformin in db/db mice. Furthermore, glucose tolerance was also improved in sphingosine (d18:1)-JGL-sRNA-h7 bencaosomes-treated beagle dogs. Our study indicates that JGL-sRNA-h7 could be a promising hypoglycemic oligonucleotide drug.

High spectral efficiency modulation scheme based on joint interaction of orthogonal compressed chirp division multiplexing and power superimposed code.

In this paper, we propose a high spectral efficiency modulation scheme based on joint interaction of orthogonal compressed chirp division multiplexing (OCCDM) and power superimposed code (PSC) under the intensity modulation and direct detection (IM/DD) system. OCCDM is a novel orthogonal chirp division multiplexing technology featuring spectral compression through the implementation of processing similar to a discrete Fourier transform, enhancing the spectral efficiency (SE) through bandwidth savings without loss of orthogonality of each chirp. Meanwhile, PSC technology enables multiple code words being transmitted superimposed on the same chirp. This technique involves allocating varying power levels to different users, thereby distinguishing them, increasing the transmission's net bit rate and substantially boosting the SE. The transmission has been performed experimentally using a 2 km 7-core fiber span. The impact of the above-mentioned technologies on the bit error rate (BER) performance is assessed in the power, frequency, and joint domain. The BER and enhancements in the SE can be balanced when the spectral bandwidth compression factor (α) and power distribution ratio are equal to 0.9 and 4, respectively. The observed outcome leads to the transmission's SE increase to more than double the baseline value, at 2.22 times. Based on the above analysis, we believe this structure is expected to become a potential for developing next-generation PON.

Physical layer security scheme for key concealment and distribution based on carrier scrambling.

The purpose of this study is to present a physical layer security scheme for key concealment and distribution based on carrier scrambling. The three-dimensional (3D) Lorenz system is used to generate independent chaotic sequences that encrypt the information with bit, constellation and subcarrier. In order to realize the flexible distribution of the key and ensure its security, the key information is loaded into a specific subcarrier. While key subcarrier and the ciphertext subcarrier are scrambled simultaneously. The encrypted key position information is processed and transmitted in conjunction with the training sequence (TS) to facilitate demodulation by the legitimate receiver. The processed TS can accommodate up to 10 key position information, thereby demonstrating the scheme's exceptional scalability. Experimental results show that the proposed scheme can safely transmit 131.80 Gb/s Orthogonal frequency division multiplexing (OFDM) signals across 2 km 7-core fiber. Meanwhile, the scheme enables simultaneous flexible distribution and concealment of the key, thereby offering a promising solution for physical layer security.

Chaos key enhanced physical layer secure transmission method based on the convolutional long short-term memory neural network.

In this paper, we propose a method for training a key-enhanced chaotic sequence using the convolutional long short term memory neural network (CLSTM-NN) for secure transmission. This method can cope with the potential security risk posed by the degradation of chaotic dynamics when using chaotic model encryption in traditional secure transmissions. The simulation results show that the proposed method improves the key space by 1036 compared to traditional chaotic models, reaching 10241. The method was applied to orthogonal chirp division multiplexing (OCDM). To demonstrate the feasibility of the proposed scheme, we conducted transmission experiments of encrypted 16 quadrature amplitude modulation (QAM) OCDM signals at a speed of 53.25 Gb/s over a 2 km length of 7-core optical fiber and test different encryption schemes. After key enhancements, the overall number of keys in the system can increase from 18 to 105.The results show that there is no significant difference between the bit error rate (BER) performance of the encryption method proposed in this paper and the traditional encryption method. The maximum performance difference between the different systems does not exceed 1 dBm. This fact proves the feasibility of the proposed scheme and provides new ideas for the next generation of secure transmission.

Therapeutic strategies targeting mechanisms of macrophages in diabetic heart disease.

Diabetic heart disease (DHD) is a serious complication in patients with diabetes. Despite numerous studies on the pathogenic mechanisms and therapeutic targets of DHD, effective means of prevention and treatment are still lacking. The pathogenic mechanisms of DHD include cardiac inflammation, insulin resistance, myocardial fibrosis, and oxidative stress. Macrophages, the primary cells of the human innate immune system, contribute significantly to these pathological processes, playing an important role in human disease and health. Therefore, drugs targeting macrophages hold great promise for the treatment of DHD. In this review, we examine how macrophages contribute to the development of DHD and which drugs could potentially be used to target macrophages in the treatment of DHD.

Enhancing secure transmission and key distribution for ultrahigh-order QAM via delta-sigma modulation and discrete memristive-enhanced chaos.

In this Letter, we propose a method for ultrahigh-order QAM secure transmission and key distribution based on delta-sigma modulation (DSM) and discrete memristive-enhanced chaos (DMEC). The disturbance vectors generated by the DMEC scramble the DSM signals in both frequency and time domains, resulting in highly secure DSM signals. Through the key modulation and power adjustment and then superimposing them on the encrypted signals, the method achieves simultaneous transmission of keys and signals without the need for additional spectral resources. This approach allows for secure communication with continuous key iteration and updates, offering an effective solution for implementing "one-time pad" encryption. In the experimental demonstration, we achieved a secure transmission and key distribution of a 16384QAM signal at a rate of 17.09 Gb/s over 25 km in an intensity-modulated direct detection (IMDD) system, based on DSM.

Early smoking lead to worse prognosis of COPD patients: a real world study.

BACKGROUND: Smoking remains a major risk factor for the development and progression of chronic obstructive pulmonary disease (COPD). Due to the adolescent smoking associated with worse health state, the age, at which an individual started smoking, might play a key role in shaping the trajectory of COPD development and the severity. METHODS: We conducted an observational study from September 2016 through January 2023 of eligible patients hospitalized with COPD. Patients who started smoking during the alveolar development stage (ADS, smoking initiation ≤ 24 years old) were defined as early smoking patients, and patients who started smoking after ADS (smoking initiation > 24 years old) were defined as late smoking patients. We collected demographic and clinical data characterizing the patients and documented their condition from hospital discharge to follow-up. The primary endpoints were short-term (within one year), 3-year, and long-term (beyond 3 years) all-cause mortality after discharge. RESULTS: Among 697 COPD patients, early smoking patients had a lower smoking cessation rate (P < 0.001) and a higher smoking index (P < 0.001) than late smoking patients. Although adjusted smoking index, early smoking patients still had poorer lung function (P = 0.023), thicker left ventricular diameters (P = 0.003), higher frequency of triple therapy use during stable stage (P = 0.049), and more acute exacerbations in the past year before enrollment (P < 0.05). Survival analysis showed that they had a higher risk of death after discharge within three years (P = 0.004) and beyond three years (P < 0.001). Furthermore, even in early smoking COPD patients who quit smoking after adjusting the smoking index had poorer lung function (P < 0.05) and thicker left ventricular diameters (P = 0.003), and survival analysis also showed that they had a higher long-term mortality rate (P = 0.010) and shorter survival time (P = 0.0128). CONCLUSION: Early smoking COPD patients exhibited multiple adverse clinical outcomes, including heavy cigarette addiction, compromised pulmonary function, augmented left ventricular diameter, and elevated mortality risk. Additional, smoking cessation could not bring enough improvement of health state in early smoking COPD patients as late smoking COPD patients. Consequently, early intervention and specialized cessation approaches for younger smokers are of paramount importance in this context.

Errors and Adherence to Inhaled Medications in Chinese Adults with COPD.

BACKGROUND: Adherence to inhaled medications is key to chronic obstructive pulmonary disease (COPD) control and management. OBJECTIVE: To assess errors and adherence to inhalation therapy in COPD patients, and identify potential factors associated with poor adherence. METHODS: This cross-sectional study was conducted from October 1, 2022, to November 30, 2022, in 24 hospital outpatient departments in different cities of Hunan Province, China. Adherence to inhaled medications was measured using the 10-item Test of Adherence Inventory, and the results were expressed using both descriptive and inferential statistics. RESULTS: A total of 2218 clinically confirmed adult COPD patients completed the questionnaires, and 1423 patients with more than a 3-month history of inhalation therapy were analyzed. This study found that 61.3% of patients made one or more use errors. Not holding the breath after inhalation or holding the breath for less than 3 s had the highest reporting rate (30.7%). A considerable proportion of patients (66.6%) demonstrated suboptimal adherence to inhaled medications. Patients who resided in rural areas (OR 1.45, 95% CI 1.12-1.88), used dual therapy (OR 1.47, 95% CI 1.05-2.05), and exhibited common use errors (OR 3.02, 95% CI 2.39-3.82) were more likely to present suboptimal adherence. Patients with CAT (Chronic Obstructive Pulmonary Disease Assessment Test) score < 10 (OR 0.73, 95% CI 0.56-0.94), a junior high school education and above (OR 0.73, 95% CI 0.57-0.94), and duration of inhaled medication use > 3 years (OR 0.63, 95% CI 0.47-0.83) were associated with better adherence. CONCLUSION: Suboptimal adherence to inhaled medications and many inhalation therapy errors were identified among COPD patients. Common use errors in inhaled medications, CAT score, and education background were predictive of and influenced adherence to inhaled medications. It is necessary to strengthen training in Chinese patients about inhaler use and follow-up intensively with patients throughout treatment, especially for patients with risk factors.

Enantiomer Recognition Based on Chirality Transfer from Chiral Amines to Ternary Dynamic Covalent Systems.

Enantiomer recognition is usually required in organic synthesis and materials and life sciences. This paper describes an enantiomer recognition method based on ternary dynamic covalent systems constructed via the complexation of chiral amines with a chiral boronate derived from 1,4-phenylenediboric acid and an L-DOPA-modified naphthalenediimide. The ternary systems aggregate into chiral assemblies driven by π-π interactions, and the chirality is transferred from the chiral amines to assemblies with high stereospecificity. Consequently, the enantiomer composition of chiral amines and the absolute configuration of the major enantiomer can be determined according to the sign of the Cotton effect of the ternary system by using circular dichroism (CD) spectroscopy. This method offers the advantage of using the long wavelength CD signals of the boronate at around 520 nm, thereby avoiding interference with those of the carbon skeleton. This ternary system provides a novel approach to the design of enantiomer recognition systems.

Polarization angle information enhancement method based on polarimetric array imaging.

Polarization imaging, based on the measurement of polarization parameters containing specific physical information, has found extensive applications across various domains. Among these parameters, polarization angle information plays a crucial role in revealing texture details. However, in practical scenarios, noise during image acquisition can lead to significant degradation of polarization angle information. To address this issue, we introduce a novel, to the best of our knowledge, polarization angle information enhancement method based on polarimetric array imaging. Our proposed method utilizes the principles of polarimetric array imaging to effectively restore texture information embedded within polarization angle images. Through the deployment of a self-designed polarimetric array imaging system, we conducted experiments in diverse scenes to validate the efficacy of our approach. The acquired polarization angle data were subjected to our method for enhancement. The experimental outcomes distinctly illustrate the noise suppression capabilities of our method, showcasing its ability to faithfully reconstruct intricate details obscured by substantial noise interference.

Efficient targeted recombination with CRISPR/Cas9 in hybrids of Caenorhabditis nematodes with suppressed recombination.

BACKGROUND: Homology-based recombination (HR) is the cornerstone of genetic mapping. However, a lack of sufficient sequence homology or the presence of a genomic rearrangement prevents HR through crossing, which inhibits genetic mapping in relevant genomic regions. This is particularly true in species hybrids whose genomic sequences are highly divergent along with various genome arrangements, making the mapping of genetic loci, such as hybrid incompatibility (HI) loci, through crossing impractical. We previously mapped tens of HI loci between two nematodes, Caenorhabditis briggsae and C. nigoni, through the repeated backcrossing of GFP-linked C. briggsae fragments into C. nigoni. However, the median introgression size was over 7 Mb, indicating apparent HR suppression and preventing the subsequent cloning of the causative gene underlying a given HI phenotype. Therefore, a robust method that permits recombination independent of sequence homology is desperately desired. RESULTS: Here, we report a method of highly efficient targeted recombination (TR) induced by CRISPR/Cas9 with dual guide RNAs (gRNAs), which circumvents the HR suppression in hybrids between the two species. We demonstrated that a single gRNA was able to induce efficient TR between highly homologous sequences only in the F1 hybrids but not in the hybrids that carry a GFP-linked C. briggsae fragment in an otherwise C. nigoni background. We achieved highly efficient TR, regardless of sequence homology or genetic background, when dual gRNAs were used that each specifically targeted one parental chromosome. We further showed that dual gRNAs were able to induce efficient TR within genomic regions that had undergone inversion, in which HR-based recombination was expected to be suppressed, supporting the idea that dual-gRNA-induced TR can be achieved through nonhomology-based end joining between two parental chromosomes. CONCLUSIONS: Recombination suppression can be circumvented through CRISPR/Cas9 with dual gRNAs, regardless of sequence homology or the genetic background of the species hybrid. This method is expected to be applicable to other situations in which recombination is suppressed in interspecies or intrapopulation hybrids.

The Ratio of Intraoperative Red Blood Cell Transfusion to Blood Loss Associated with Early Postoperative Complications in Pediatric Liver Transplantation Patients.

Introduction: Liver transplantation (LT) is an operation purposed to save the lives of children with acute or chronic liver diseases, hepatic tumors, and some genetic and metabolic diseases. However, patients who underwent LT have a significant risk of intraoperative blood loss and red blood cell (RBC) transfusion, especially in pediatric patients. Methods: In this study, 569 pediatric patients (<18 years old) who underwent LT at a tertiary university hospital between 2013 and 2020 were included. Multiple logistic regression was used to analyze the association between the ratio of intraoperative RBC transfusion to blood loss (IRTBL) and the complications after LT in pediatric patients. IRTBL was divided into quartiles in the adjusted model. Odds ratios, 95% confidence intervals, and p values for trends were calculated. Restricted cubic spline (RCS) regression was used to evaluate the nonlinear association between IRTBL and complications. Results: Compared with the lowest level and the highest level of IRTBL, Q2 and Q3 quartiles of IRTBL showed significantly positive association with early complications. A significantly nonlinear association was observed between the IRTBL and early complications in the RCS model with the multiple adjustments of potential covariates (P overall<0.01, P nonlinear<0.01). However, no significant association was observed between late complications and IRTBL. Conclusion: In this study, we found there was a nonlinear relationship between the ratio of IRTBL and early postoperative complications in pediatric LT patients, which provides a theoretical basis for RBC transfusion in pediatric LT patients.

Study on fermentation preparation, physicochemical properties and biological activity of carboxymethylpachymaran with different degrees of substitution.

BACKGROUND: Carboxymethylpachymaran (CMP) is created by carboxymethylating pachyman (PM), which increases its water solubility and enhances a number of biological activities. Traditional polysaccharides modified by carboxymethylation employ strong chemical techniques. Carboxymethylcellulose (CMC) has been used previously for liquid fermentation to carboxymethyl modify bacterial polysaccharides. This theory can be applied to fungal polysaccharides because Poria cocos has the ability to naturally utilize cellulose. RESULTS: CMC with different degrees of substitution (DS) (0.7, 0.9 and 1.2) were added to P. cocos fermentation medium, and CMPs with different DS (0.38, 0.56 and 0.78, respectively) were prepared by liquid fermentation. The physical and chemical properties and biological activities of the CMPs were determined. Their structures were confirmed by Fourier transform infrared (FTIR) spectroscopy and monosaccharide composition. With the increase of DS, the viscosity and viscosity-average molecular weight of CMPs decreased, whereas polysaccharide content and water solubility increased, although the triple helix structure was not affected. The results of bioactivity assay showed that the higher the DS of CMPs, the higher the 2,2-diphenyl-1-picrylhydrazyl radical scavenging ability, and the stronger the bacterial inhibition ability. CONCLUSION: The present study has developed a method for producing CMPs by P. cocos liquid fermentation. The results of the study confirm that enhancing the DS of CMP could effectively enhance its potential biological activity. The findings provide safe and reliable raw materials for creating CMP-related foods and encourage CMP application in the functional food industry. © 2024 Society of Chemical Industry.

Impact mechanism of social-related social media use on the job performance of caregivers of older adults.

This study investigated the impact mechanism of social-related social media use on the job performance of caregivers of older adults through mental health and analyzed gender differences. A total of 358 valid questionnaires were collected and analyzed using SPSS and Smart PLS. The results showed that mental health plays an important role in the relationship between social-related social media use and job performance. Such social media use can improve psychological well-being and reduce psychological distress by promoting relaxation experience. Psychological well-being has a significant positive impact on job performance. In addition, significant differences exist in the impact path of social-related social media use on psychological distress among different gender groups. The findings of this study can assist nursing homes in assessing the use of social media within their organizations and provide methodological references for enhancing the job performance of caregivers of older adults.

Computational imaging and occluded objects perception method based on polarization camera array.

Traditional optical imaging relies on light intensity information from light reflected or transmitted by an object, while polarization imaging utilizes polarization information of light. Camera array imaging is a potent computational imaging technique that enables computational imaging at any depth. However, conventional imaging methods mainly focus on removing occlusions in the foreground and targeting, with limited attention to imaging and analyzing polarization characteristics at specific depths. Conventional camera arrays cannot be used for polarization layered computational imaging. Thus, to study polarization layered imaging at various depths, we devised a flexible polarization camera array system and proposed a depth-parallax relationship model to achieve computational imaging of polarization arrays and polarization information reconstruction under varying conditions and depths. A series of experiments were conducted under diverse occlusion environments. We analyzed the distinctive characteristics of the imaging results obtained from the polarization array, employing a range of array distribution methods, materials, occlusion density, and depths. Our research successfully achieved computational imaging that incorporates a layered perception of objects. Finally, we evaluated the object region's polarization information using the gray level co-occurrence matrix feature method.

4-D constellation construction and encryption scheme based on bit-level dimension dissecting and reorganization.

A 4-dimensional (4-D) constellation construction and encryption scheme of dimension dissecting reorganization are proposed in this paper. In this scheme, the high-dimensional constellation is constructed by gradually decomposing and superimposing the low-dimensional constellation, and the mapping dimension, phase, and arrangement order of signals are scrambled to realize the encryption. This scheme uses the evolution from low dimension to high dimension to reduce the difficulty of constructing a high-dimensional constellation, and the confusion between dimensions facilitates the encryption of high-dimensional information. To verify the performance, an experiment to demonstrate the transmission of 46.7 Gb/s 4-D constellation mapping the intensity modulation/direct detection carrierless amplitude and phase on 2 km 7-core optical fiber has been successfully carried out.

Performance improvement of non-orthogonal multiple access with a 3D constellation and a 2D IFFT modulator.

In this paper, we propose a performance improvement of non-orthogonal multiple access (NOMA) with a three-dimensional (3D) constellation and a two-dimensional Inverse Fast Fourier Transform IFFT modulator (2D-IFFT) for the passive optical network (PON). Two kinds of 3D constellation mapping are designed for the generation of a three-dimensional NOMA (3D-NOMA) signal. Higher-order 3D modulation signals can be obtained by superimposing signals of different power levels by pair mapping. Successive interference cancellation (SIC) algorithm is implemented at the receiver to remove interference from different users. Compared with the traditional two-dimensional NOMA (2D-NOMA), the proposed 3D-NOMA can increase the minimum Euclidean distance (MED) of constellation points by 15.48%, which enhances the bit error rate (BER) performance of the NOMA. The peak-to-average power ratio (PAPR) of NOMA can be reduced by 2 dB. A 12.17 Gb/s 3D-NOMA transmission over 25 km single-mode fiber (SMF) is experimentally demonstrated. The results show that at the bit error rate (BER) of 3.8 × 10-3, the sensitivity gain of the high-power signals of the two proposed 3D-NOMA schemes is 0.7 dB and 1 dB compared with that of 2D-NOMA under the condition of the same rate. Low-power level signal also has 0.3 dB and 1 dB performance improvement. Compared with 3D orthogonal frequency-division multiplexing (3D-OFDM), the proposed 3D-NOMA scheme could potentially expand the number of users without obvious performance degradation. Due to its good performance, 3D-NOMA is a potential method for future optical access systems.