Integrated self-injection-locked narrow linewidth laser based on thin-film lithium niobate.

Narrow linewidth lasers have a wide range of applications in the fields of coherent optical communications, atomic clocks, and measurement. Lithium niobate material possesses excellent electro-optic and thermo-optic properties, making it an ideal photonic integration platform for a new generation. The light source is a crucial element in large-scale photonic integration. Therefore, it is essential to develop integrated narrow linewidth lasers based on low-loss LNOI. This study is based on the multimode race-track type add-drop microring resonator with multimode interferometric coupler (MMRA-MRR) of the DFB laser self-injection-locked, to achieve the narrowing of linewidth to the laser. The microring external cavity was used to narrow the linewidth of the laser to 2.5 kHz. The output power of the laser is 3.18 mW, and the side-mode suppression ratio is 60 dB. This paper presents an integrated low-noise, narrow-linewidth laser based on thin-film lithium niobate material for the communication band. This is significant for achieving all-optical device on-chip integration of lithium niobate material in the future. It has great potential for use in high-speed coherent optical communication.

Life expectancy and mental related burden of disease among people living with HIV/AIDS.

Mental health problems leads to serious disease burden among people living with HIV/AIDS (PLHIV). The study aimed at measuring the mental disorders-caused burden of disease based on PLHIV in mainland China. The data used was from the national HIV/AIDS case reporting system, life expectancy (LE) and LE-eliminated suicide were evaluated by the life-table method. The total YLLs and YLLs caused by suicide in each age group were calculated. The disability weights were estimated by the scale of depression symptoms (CES-D) from the multi-center cross-sectional survey, then calculated the corresponding YLDs as a burden of mental illness among PLHIV. Results showed that the LE had been prolonged by implementing antiviral therapy for PLHIV. The proportion of YLLs caused by suicide was the highest (5·46%) in the 15-24 age group. The YLDs in the 25-34 age group were the highest. The YLLs caused by suicide in males were higher than those in the same age group of females. The YLDs and YLLs were higher in heterosexual-infected PLHIV than in homosexual-infected PLHIV, except for YLLs in the 25-34 age group. In summary, this study first provided localized data on the disease burden caused by mental health problems among PLHIV.

Risk sexual behaviors for sexually transmitted infections among sexual minority women: A cross-sectional study in Beijing, China.

Researchers in this study assesses risk behaviors for sexually transmitted infections (STIs) among sexual minority women (SMW) in Beijing, China. A total of 1,631 SMW participated in the study. Compared with women who have sex with women exclusively, women who have sex with both women and men reported more sex partners, more likely sharing sex toys, experiencing STI infections. Digital-genital sex, using sex toys, G-spot stimulation is associated with STI symptoms. SMW in Beijing engaged in high-risk sexual behaviors that may cause substantial risk for STIs. SMW and healthcare providers should be informed and STI testing should be promoted among SMW.

Temporal and Spatial Trends in HIV Positivity Rate for VCT Clinics - China, 2015-2022.

Introduction: Human immunodeficiency virus (HIV) voluntary counseling and testing (VCT) clinics play a critical role in identifying and diagnosing HIV cases. This study aimed to describe the trend of HIV positivity rate (HPR) among Chinese VCT clinics between 2015 and 2022. Methods: This study utilized data from the China Information System for Disease Control and Prevention to analyze the trend in the HPR for VCT clinics from 2015 to 2022. The HPR was calculated by dividing the number of newly-reported HIV cases by the number of HIV tests, multiplied by 100%. To identify temporal and spatial trends in the HPR, we employed joinpoint regression analysis and the Getis-Ord hotspot analysis. Results: From 2015 to 2022, VCT clinics in China performed a total of 22,075,386 HIV tests, leading to the identification of 260,353 HIV cases, resulting in a HPR of 1.18%. The HPR consistently declined over the study period, with an average annual percent change (AAPC) of -7.5% (95% confidence interval: -12.6%, -2.2%, P<0.05). The number of HPR hotspots also decreased from 41 in 2015 to 23 in 2022. These HPR hotspots were primarily located in Yunnan, Sichuan, Guangdong, and Guangxi provincial-level administrative divisions (PLADs). Among the 31 PLADs, 16 showed a significant decrease in HPR during the study period (AAPC<0, PAAPC<0.05). Conclusions: VCT clinics in China have played a significant role in identifying HIV cases. The declining HPR observed in these clinics may indicates the progress has been made in some degree in mitigating HIV among high-risk populations. Therefore, it is crucial to further improving the utilization of VCT clinics for HIV testing.

HIV Infection and Associated Factors Among Out-of-School MSM Aged 16-24 Years - 6 Cities and Tianjin Municipality, China, 2022-2023.

What is already known about this topic?: Approximately 80% of newly diagnosed human immunodeficiency virus (HIV) cases among individuals aged 15-24 years in China are attributed to out-of-school youth. What is added by this report?: This study presents findings on HIV prevalence and comprehensive insights into HIV service utilization, risky behaviors, and prevention knowledge among young out-of-school men who have sex with men (MSM) aged 16-24 years in China. This population exhibits a disproportionately high burden of HIV, with only 51.6% of HIV cases previously diagnosed. What are the implications for public health practice?: HIV services should be expanded to include these key populations. Tailored interventions are needed to remove barriers to regular HIV services faced by young key populations.

Mogroside V alleviates inflammation response by modulating miR-21-5P/SPRY1 axis.

Mogroside V (MV) is a natural sweetener extracted from the edible plant Siraitia grosvenorii that possesses anti-inflammatory bioactivity. It has been reported that microRNAs (miRNAs) play an important role in the inflammation response suppression by natural agents. However, whether the anti-inflammation effect of mogroside V is related to miRNAs and the underlying mechanism remains unclear. Our study aimed to identify the key miRNAs important for the anti-inflammation effect of MV and reveal its underlying mechanisms. Our results showed that MV effectively alleviated lung inflammation in ovalbumin-induced (OVA-induced) asthmatic mice. miRNA-seq and mRNA-seq combined analysis identified miR-21-5p as an important miRNA for the inflammation inhibition effect of MV and it predicted SPRY1 to be a target gene of miR-21-5p. We found that MV significantly inhibited the production of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-2 (IL-2), interleukin-6 (IL-6), and nitric oxide (NO), as well as the protein expression of p-P65/P65, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) in OVA-induced asthmatic mice and LPS-treated RAW 264.7 cells. Moreover, the release of ROS increased in LPS-stimulated RAW 264.7 cells but was mitigated by MV pretreatment. In the meantime, the expression of miR-21-5p was decreased by MV, leading to an increase in the expression of SPRY1 in RAW 264.7 cells. Furthermore, miR-21-5p overexpression or SPRY1 knockdown reversed MV's protective effect on inflammatory responses. Conversely, miR-21-5p inhibition or SPRY1 overexpression enhanced MV's effect on inflammatory responses in LPS-exposed RAW 264.7 cells. Therefore, the significant protective effect of mogroside V on inflammation response is related to the downregulation of miR-21-5p and upregulation of SPRY1 in vitro and in vivo, MiR-21-5p/SPRY1 may be novel therapeutic targets of MV for anti-inflammation treatment.

Sexually transmitted infections and associated risk factors among sexual minority women in China.

There is a potential for transmission of sexually transmitted infections (STIs) within sexual minority women (SMW) in China. However, research specifically focused on STIs among SMW in China is severely limited. This study aims to evaluate the prevalence of STIs and identify associated risk factors among SMW in Beijing, China. This study comprised a baseline assessment followed by a follow-up evaluation. Consistent questionnaire interviews and STI tests were administered during both stages. Participants were recruited online in Beijing between 2020 and 2021 and factors associated with STIs were analyzed using logistic and Cox regression models. The baseline included 219 SMW, and 58.9% (129/219) of these individuals participated in the follow-up. During the baseline assessment, 4.1% (9/219) tested positive for chlamydia infection, while 5.0% (11/219) were HSV-2 seropositive. At the follow-up, the incidence of HSV-2 was 3.7 cases per 100 person-years. Notably, engaging in sexual activity with men and having an increased number of sexual partners were both identified as factors associated with a higher risk of STIs. The findings suggest that SMW in Beijing may face a significant risk of contracting STIs. As a preventive measure, there should be a concerted effort to promote STI testing within the SMW community.

Changing Mortality and Patterns of Death Causes in HIV Infected Patients - China, 2013-2022.

What is already known about this topic?: The advent of antiretroviral therapy (ART) has markedly decreased mortality rates among patients infected with human immunodeficiency virus (HIV). Globally, there has been a 43% reduction in acquired immunodeficiency syndrome (AIDS)-related deaths from 2010 to 2022. Additionally, prior research indicates that the initiation of ART at an early stage within China has substantially lowered mortality rates. What is added by this report?: Over the previous decade, following the implementation of China's universal ART access strategy, the patterns of mortality causes among HIV-infected individuals across the country have undergone significant alterations. In 2022, the all-cause mortality rate among this population was reported at 2.7%, with the non-AIDS-related mortality rate at 1.8%. However, it is important to consider that the accuracy of death reporting could contribute to potential misclassification of the underlying causes of death. What are the implications for public health practice?: Efforts to enhance health outcomes should persist in emphasizing the advancement of ART strategies, with a particular focus on mitigating non-AIDS-related mortality in the future.

Trends in Mortality and Prevalence of Reported HIV/AIDS Cases - China, 2002-2021.

What is already known about this topic?: Annually, only the incidence and mortality for Acquired Immune Deficiency Syndrome (AIDS) patients are officially disclosed. What is added by this report?: For the first time, information detailing the reported rate, mortality rate, and prevalence rate trends of HIV, AIDS, and HIV/AIDS in China's entire population over the past two decades has been provided. What are the implications for public health practice?: Our research overcomes the longstanding limitation of HIV/AIDS analysis as the sole denominator. Rather, it incorporates a comprehensive examination of the overall population, utilizing indicators and analytic methods from chronic disease analyses.

Broadband electromagnetic wave absorption using pure carbon aerogel by synergistically modulating propagation path and carbonization degree.

Carbon materials were widely used as electromagnetic (EM) wave absorption due to their advantages of light weight, environmental resistance and high electrical conductivity. However, conventional means were typically available by combining carbon and other materials to achieve effective absorption. Herein, a novel strategy using pure carbon aerogel with oriented structure was reported to enhance the EM wave absorption by synergistically modulating the wave propagation path and carbonization degree. The aerogel contained proposed modified carbon nanofibers (MCNF) derived from bacterial cellulose (BC), and core-shell carbon nanofibers @ reduced oxide graphene (CNF@RGO). The oriented structure was induced by the temperature field, which manifests anisotropic EM constitutive parameters (εx ≠ Îµz) at different directions of incident wave. The carbonization degree was adjusted by varying the carbonization temperature. At the carbonization temperature of 700 °C, the maximum reflection loss and effective absorption bandwidth reached -53.94 dB and 7.14 GHz, respectively, enabling the aerogel to outperform its previous counterparts. To clarify the EM wave mode-of-action in conjunction, physical models of the aerogel were established in addition to finite element simulation and theoretical analysis. Notably, the aerogel with a density of 3.6 mg/cm3 featured ultra-light weight, superhydrophobicity, superior compressibility, and thermal insulation. Our work offers an efficient strategy for designing broadband and multifunctional EM wave absorption materials (EWAMs), promising great potentials in complex stealth equipment.

RNA-binding domain 2 of nucleolin is important for the autophagy induction of curcumol in nasopharyngeal carcinoma cells.

BACKGROUND & AIMS: Excessive autophagy induces cell death and is regarded as the treatment of cancer therapy. We have confirmed that the anti-cancer mechanism of curcumol is related to autophagy induction. As the main target protein of curcumol, RNA binding protein nucleolin (NCL) interacted with many tumor promoters accelerating tumor progression. However, the role of NCL in cancer autophagy and in curcumol's anti-tumor effects haven't elucidated. The purpose of the study is to identify the role of NCL in nasopharyngeal carcinoma autophagy and reveal the immanent mechanisms of NCL played in cell autophagy. METHODS & RESULTS: In the current study, we have found that NCL was markedly upregulated in nasopharyngeal carcinoma (NPC) cells. NCL overexpression effectively attenuated the level of autophagy in NPC cells, and NCL silence or curcumol treatment obviously aggravated the autophagy of NPC cells. Moreover, the attenuation of NCL by curcumol lead a significant suppression on PI3K/AKT/mTOR signaling pathway in NPC cells. Mechanistically, NCL was found to be directly interact with AKT and accelerate AKT phosphorylation, which caused the activation of the PI3K/AKT/mTOR pathway. Meanwhile, the RNA Binding Domain (RBD) 2 of NCL interacts with Akt, which was also influenced by curcumol. Notably, the RBDs of NCL delivered AKT expression was related with cell autophagy in the NPC. CONCLUSION: The results demonstrated that NCL regulated cell autophagy was related with interaction of NCL and Akt in NPC cells. The expression of NCL play an important role in autophagy induction and further found that was associated with its effect on NCL RNA-binding domain 2. This study may provide a new perspective on the target protein studies for natural medicines and confirm the effect of curcumol not only regulating the expression of its target protein, but also influencing the function domain of its target protein.

Multifunctional microwave absorption materials of multiscale cobalt sulfide/diatoms co-doped carbon aerogel.

Microwave absorption materials (MAMs) have attracted much attention for their potential applications in stealth technology and prevention of electromagnetic pollution problems. Multifunctional MAMs are highly demanded because they can be applied in harsh environments. Hence, based on multiscale manipulation of atomic engineering, nanostructure and microstructure, a multiscale hollow cobalt sulfide/diatoms co-doped carbon aerogel was preparedthrough the physical crosslinking of divalent ions, unidirectional freezing, kirkendall effect, and heteroatomic doping. The aerogel with a low density of 13.1 mg/mm3 has a unique "lamellar-pillar" network structure due to the growth of ice crystals during the preparation process. With the assistance of thiourea, the doping of N, S atoms and the construction of hollow cobalt sulfide are accomplished simultaneously. The ingenious integration facilitates the synergistic effect of conductive loss, defect polarization, interfacial polarization, and multiple scattering. The multiscale hollow cobalt sulfide/diatoms co-doped carbon aerogel had a maximum reflection loss of -51.96 dB and an effective absorption bandwidth of 6.4 GHz, which is higher than that of other reported MAMs. It is further verified through finite element simulation and experiments that the aerogel has an excellent microwave absorption properties. In addition, the aerogel has excellent thermal insulation and flame retardant properties. Therefore, the development of this aerogel can help to use MAMs in complex applications.

Understanding the Uptake and Outcomes of Non-occupational Postexposure Prophylaxis Use Through an Online Medical Platform in China: Web-Based Cross-sectional Study.

BACKGROUND: To date, non-occupational postexposure prophylaxis (PEP) has been widely accepted as a safe and effective intervention for HIV in many countries, yet it remains an underutilized prevention strategy in China. Evidence indicated a high demand for PEP among Chinese men who have sex with men, but the uptake and access to PEP service remain limited. In an era of rapid development of web-based technology, online medical platforms in China hold great promise in facilitating PEP provision and delivery by addressing problems such as accessibility, convenience, privacy protection, and antidiscrimination by integrating online and offline resources. However, there is a paucity of data concerning the uptake and outcomes of online PEP in China. OBJECTIVE: The aim of this study is to explore online PEP service provision and understand PEP uptake and outcome through a web-based cross-sectional study. METHODS: From January 2020 to June 2021, we conducted a retrospective web-based survey among those seeking online PEP services via the internet medical platform "HeHealth" using a structured questionnaire. Participants were surveyed on sociodemographic characteristics, sexual and drug-related behaviors, history of preexposure prophylaxis (PrEP) usage, and PEP uptake. Statistical analysis included descriptive analysis, chi-square test, and multivariable logistic regression. P values <.05 were deemed statistically significant. RESULTS: No HIV seroconversions were observed among 539 PEP users. Our sample demonstrated that most participants seeking online PEP services were gay (397/539, 73.7%), single (470/539, 87.2%), having an education of more than 12 years (493/539, 91.5%), and with an average monthly income of 7000 RMB (1 RMB=US $0.14) or more (274/539, 50.8%). Sexual exposures accounted for 86.8% (468/539) of the cases, with anal sex being the most common indication (389/539, 72.2%) for seeking PEP use. Among 539 participants, 60.7% (327/539) sought online PEP for relatively low-risk exposures, whereas 39.3% (212/539) were considered high-risk exposures. Nearly all (537/539, 99.6%) initiated PEP within 72 hours and 68.6% (370/539) within 24 hours of exposure. All users (539/539) were prescribed a 3-drug regimen, with most comprising 3TC/TDF+DTG (lamivudine, tenofovir disoproxil fumarate, and dolutegravir; 293/539, 54.4%), followed by FTC/TDF+DTG (emtricitabine, tenofovir disoproxil fumarate, and dolutegravir; 158/539, 29.3%). The adjusted model showed that greater odds of PrEP usage were associated with an age of 35 years or older versus the age group of 25-34 years (adjusted odds ratio [AOR] 2.04, 95% CI 1.24-3.37), having an education of 17 years or more versus an education of 12 years or less (AOR 3.14, 95% CI 1.29-7.62), average monthly income of 20,000 RMB or more versus less than 3000 RMB (AOR 2.60, 95% CI 1.09-6.23), and having high-risk sexual behavior during PEP treatment (AOR 2.20, 95% CI 1.05, 3.69). CONCLUSIONS: The 0% infection rate in this study demonstrated that online PEP could be a valuable risk-reduction option to improve HIV prevention service within China. However, further research is needed to better facilitate PrEP transition among online PEP users.

Optimizing Respondent-Driven Sampling Survey to Identify Factors Associated With HIV Risk Behaviors Among Student MSM Aged 15 to 19.

Male homosexual behavior dominates the mode of HIV infection among students in China. This study aims to identify factors associated with HIV risk behaviors among male students who have sex with men (student MSM) aged 15 to 19 in China. The online sampling used the standard respondent-driven sampling (RDS) method, with recruitment support from community-based organizations (CBOs) in Tianjin and Guangzhou. Multivariate logistic regression models were performed to identify factors associated with multiple HIV risk behaviors. A total of 449 subjects were recruited in this study, including 206 in Tianjin and 243 in Guangzhou. The presence of multiple HIV risk behaviors among student MSM, in many cases, was found to positively correlate with parental or friends' awareness of their same-sex sexual behavior or sexual orientation, with some geographical differences. The prevalence of HIV risk behaviors among student MSM aged 15 to 19 was high and associated with the disclosure of their sexual orientation or their sex with males to parents and friends. These findings highlight the importance of addressing social support in HIV prevention among student MSM when delivering HIV-related education or services.

Estimation of reduced greenhouse gas emission from municipal solid waste incineration with electricity recovery in prefecture- and county-level cities of China.

Municipal solid waste (MSW) without proper managements could be a significant source of greenhouse gas (GHG) emissions. MSW incineration with electricity recovery (MSW-IER) is recognized as a sustainable way to utilize waste, but its effectiveness on reducing GHG emissions at the city scale in China remain unclear due to limited data of MSW compositions. The aim of the study is to investigate reduction potential of GHG from MSW-IER in China. Based on the MSW compositions covering 106 Chinese prefecture-level cities during the period of 1985 to 2016, random forest models were built to predict MSW compositions in Chinese cities. MSW compositions in 297 cities of China from 2002 to 2017 were predicted using the model trained by a combination of socio-economic, climate and spatiotemporal factors. Spatiotemporal and climatic factors (such as economic development level, precipitation) accounted for 6.5 %-20.7 % and 20.1 %-37.6 % to total contributions on MSW composition, respectively. The GHG emissions from MSW-IER in each Chinese city were further calculated based on the predicted MSW compositions. The plastic is the main GHG emission source, accounting for over 91 % of the total emission during 2002-2017. Compared to baseline (landfill) emission, the GHG emission reduction from MSW-IER was 12.5 × 107 kg CO2-eq in 2002 and 415 × 107 kg CO2-eq in 2017, with an average annual growth rate of 26.3 %. The results provide basic data for estimating GHG emission in MSW management in China.

An integrated group decision-making method for the evaluation of hypertension follow-up systems using interval-valued q-rung orthopair fuzzy sets.

It is imperative to comprehensively evaluate the function, cost, performance and other indices when purchasing a hypertension follow-up (HFU) system for community hospitals. To select the best software product from multiple alternatives, in this paper, we develop a novel integrated group decision-making (GDM) method for the quality evaluation of the system under the interval-valued q-rung orthopair fuzzy sets (IVq-ROFSs). The design of our evaluation indices is based on the characteristics of the HFU system, which in turn represents the evaluation requirements of typical software applications and reflects the particularity of the system. A similarity is extended to measure the IVq-ROFNs, and a new score function is devised for distinguishing IVq-ROFNs to figure out the best IVq-ROFN. The weighted fairly aggregation (WFA) operator is then extended to the interval-valued q-rung orthopair WFA weighted average operator (IVq-ROFWFAWA) for aggregating information. The attribute weights are derived using the LINMAP model based on the similarity of IVq-ROFNs. We design a new expert weight deriving strategy, which makes each alternative have its own expert weight, and use the ARAS method to select the best alternative based on these weights. With these actions, a GDM algorithm that integrates the similarity, score function, IVq-ROFWFAWA operator, attribute weights, expert weights and ARAS is proposed. The applicability of the proposed method is demonstrated through a case study. Its effectiveness and feasibility are verified by comparing it to other state-of-the-art methods and operators.

Spatiotemporal Distribution of HIV Self-testing Kits Purchased on the Web and Implications for HIV Prevention in China: Population-Based Study.

BACKGROUND: HIV self-testing (HIVST) holds great promise for expanding HIV testing. Nonetheless, large-scale data on HIVST behavior are scant. Millions of HIVST kits are sold through e-commerce platforms each year. OBJECTIVE: This study aims to analyze the spatiotemporal distribution of the HIVST kit-purchasing population (HIVSTKPP) in China. METHODS: Deidentified transaction data were retrieved from a leading e-commerce platform in China. A joinpoint regression model was used to examine annual trends of the HIVSTKPP rates by calculating average annual percentage change. Bayesian spatiotemporal analysis was performed to locate hot spots with HIVSTKPP rates. Spatial autocorrelation analysis and space-time cluster analysis were conducted to identify clusters of HIVSTKPP. High-high clusters of HIVSTKPP can be identified by spatial autocorrelation analysis, and high-high clusters indicate that a region and its surrounding region jointly had a higher-than-average HIVSTKPP rate. Spatial regression analysis was used to elucidate the association between the number of HIV testing facilities, urbanization ratio (the proportion of urban population in the total population), and gross domestic product per capita and the HIVSTKPP. RESULTS: Between January 1, 2016, and December 31, 2019, a total of 2.18 million anonymous persons in China placed 4.15 million orders and purchased 4.51 million HIVST kits on the web. In each of these 4 years, the observed monthly size of the HIVSTKPP peaked in December, the month of World AIDS Day. HIVSTKPP rates per 100,000 population significantly increased from 20.62 in 2016 to 64.82 in 2019 (average annual percentage change=48.2%; P<.001). Hot spots were mainly located in municipalities, provincial capitals, and large cities, whereas high-high clusters and high-demand clusters were predominantly detected in cities along the southeast coast. We found positive correlations between a region's number of HIV testing facilities, urbanization ratio, and gross domestic product per capita and the HIVSTKPP. CONCLUSIONS: Our study identified key areas with larger demand for HIVST kits for public health policy makers to reallocate resources and optimize the HIV care continuum. Further research combining spatiotemporal patterns of HIVST with HIV surveillance data is urgently needed to identify potential gaps in current HIV-monitoring practices.

In-situ construction of nitrogen-doped reduced graphene oxide@carbon nanofibers towards the synergetic enhancement of their microwave absorption properties via integrating point defects and structure engineering.

The aim of this work is to develop materials that can absorb microwave to meet the requirements of stealth technology and solve the problem of electromagnetic pollution. However, the challenge is having materials with high-efficient absorption properties at an ultralow filling rate and visualizing the microwave response. The strategy used in this work was to integrate point defect and microstructure in preparing materials, nitrogen-doped reduced graphene oxide@ carbon nanofibers with high-efficient microwave absorption and double-layered structure. Ethylenediamine (nitrogen source), was doped into the materials, resulting in the generation of the defects. The microwave absorption performance of the materials was affected by the degree of defects due to the dipole polarization loss and conductive loss. The optimal samples gained the maximum reflection loss of -54.7 dB and effective absorption bandwidth of 4.74 GHz at a filling rate of only 8 wt%. More significantly, the microwave absorbing mechanism was analyzed visually in the response field. Furthermore, the actual stealth effects were evaluated by the radar cross section reduction, and the value was 29.2 dBm2. The experimental results illustrated that nitrogen-doped reduced graphene oxide@ carbon nanofibers may be alternative materials with high microwave absorption performance at a low filling rate.