Iron deficiency anemia(IDA)is a nutritional deficiency disease with a high incidence rate worldwide.Bioactive peptides are safe and effective,have multiple functions and can serve as potential candidates for alleviati...Iron deficiency anemia(IDA)is a nutritional deficiency disease with a high incidence rate worldwide.Bioactive peptides are safe and effective,have multiple functions and can serve as potential candidates for alleviating IDA.In this study,the anti-anemia effects of tuna dark muscle peptides were explored in a dietinduced IDA mouse model.The results showed that tuna dark muscle peptides alleviated the IDA phenotype,oxidative stress and iron metabolism.In addition,tuna dark muscle peptides reversed gut microbiota dysbiosis in IDA mice.Furthermore,the transplanted fecal microbiota from tuna dark muscle peptide-treated mice also alleviated IDA symptoms and regulated iron metabolism and the gut microbiota,indicating that the antianemic effects were at least partially mediated by the gut microbiota.Thus,we identified a new and safe prebiotic material to alleviate IDA and provided ideas for the development of peptides.At the same time,these data also provided a theoretical basis for fecal microbiota transplantation to alleviate IDA.展开更多
Background:Acute suppurative terminal cholangitis(ASTC)is rarer than acute obstructive cholangitis and is not well studied.To explore this subtype of acute cholangitis,we described our clinical experience with ASTC.Me...Background:Acute suppurative terminal cholangitis(ASTC)is rarer than acute obstructive cholangitis and is not well studied.To explore this subtype of acute cholangitis,we described our clinical experience with ASTC.Methods:We performed a retrospective review of patients with ASTC admitted to our center from September 2014 to August 2020.We analyzed their clinical characteristics,including etiology,clinical manifestations,imaging features,treatment and prognosis.Results:A total of 32 ASTC patients were included in the analysis.The majority of the patients had a history of biliary operations,and clinical manifestations were occult and atypical.The positive rate of bacterial culture was 46.9%.All the patients had typical imaging features on computed tomography and magnetic resonance imaging.Treatment with effective antibiotics was provided as soon as diagnosis was established.After treatment,most patients had a good outcome.Elevated levels of total bilirubin,aspartate aminotransferase,procalcitonin and gamma-glutamyltransferase were the characteristics of critically ill patients and were associated with relatively poor prognosis.Conclusions:Our results demonstrated that ASTC should be recognized as a new subtype of acute cholangitis,and that earlier diagnosis and more personalized treatments are needed.展开更多
Tetanus is the only non-communicable disease among vaccine-preventable infectious diseases.It is caused by an infection with Clostridium tetanus bacterium and is characterized by continuous tonic contraction and parox...Tetanus is the only non-communicable disease among vaccine-preventable infectious diseases.It is caused by an infection with Clostridium tetanus bacterium and is characterized by continuous tonic contraction and paroxysmal spasms of skeletal muscles throughout the body[1].展开更多
Human immunodeficiency virus(HIV)is a serious public health concern.Globally,1.7 million(1.3–2.1 million)children aged 0–14 were living with HIV at the end of 2021,90%of whom lived in low-and middle-income countries...Human immunodeficiency virus(HIV)is a serious public health concern.Globally,1.7 million(1.3–2.1 million)children aged 0–14 were living with HIV at the end of 2021,90%of whom lived in low-and middle-income countries.Acquired Immune Deficiency Syndrome(AIDS)remains the leading cause of mortality among children worldwide.展开更多
The attention mechanism can extract salient features in images,which has been proved to be effective in improving the performance of person re-identification(Re-ID).However,most of the existing attention modules have ...The attention mechanism can extract salient features in images,which has been proved to be effective in improving the performance of person re-identification(Re-ID).However,most of the existing attention modules have the following two shortcomings:On the one hand,they mostly use global average pooling to generate context descriptors,without highlighting the guiding role of salient information on descriptor generation,resulting in insufficient ability of the final generated attention mask representation;On the other hand,the design of most attention modules is complicated,which greatly increases the computational cost of the model.To solve these problems,this paper proposes an attention module called self-supervised recalibration(SR)block,which introduces both global and local information through adaptive weighted fusion to generate a more refined attention mask.In particular,a special"Squeeze-Excitation"(SE)unit is designed in the SR block to further process the generated intermediate masks,both for nonlinearizations of the features and for constraint of the resulting computation by controlling the number of channels.Furthermore,we combine the most commonly used Res Net-50 to construct the instantiation model of the SR block,and verify its effectiveness on multiple Re-ID datasets,especially the mean Average Precision(m AP)on the Occluded-Duke dataset exceeds the state-of-the-art(SOTA)algorithm by 4.49%.展开更多
After reconstructing the anterior cruciate ligament(ACL),unsatisfactory bone tendon interface healing may often induce tunnel enlargement at the early healing stage.With good biological features and high formability,M...After reconstructing the anterior cruciate ligament(ACL),unsatisfactory bone tendon interface healing may often induce tunnel enlargement at the early healing stage.With good biological features and high formability,Magnesium-Zinc-Gadolinium(ZG21)wires are developed to bunch the tendon graft for matching the bone tunnel during transplantation.Microstructure,tensile strength,degradation,and cytotoxicity of ZG21 wire are evaluated.The rabbit model is used for assessing the biological effects of ZG21 wire by Micro-CT,histology,and mechanical test.The SEM/EDS,immunochemistry,and in vitro assessments are performed to investigate the underlying mechanism.Material tests demonstrate the high formability of ZG21 wire as surgical suture.Micro-CT shows ZG21 wire degradation accelerates tunnel bone formation,and histologically with earlier and more fibrocartilage regeneration at the healing interface.The mechanical test shows higher ultimate load in the ZG21 group.The SEM/EDS presents ZG21 wire degradation triggered calcium phosphate(Ca-P)deposition.IHC results demonstrate upregulation of Wnt3a,BMP2,and VEGF at the early phase and TGFβ3 and Type II collagen at the late phase of healing.In vitro tests also confirmed the Ca-P in the metal extract could elevate the expression of Wnt3a,βcatenin,ocn and opn to stimulate osteogenesis.Ex vivo tests of clinical samples indicated suturing with ZG21 wire did not weaken the ultimate loading of human tendon tissue.In conclusion,the ZG21 wire is feasible for tendon graft bunching.Its degradation products accelerated intra-tunnel endochondral ossification at the early healing stage and therefore enhanced bone-tendon interface healing in ACL reconstruction.展开更多
The objective of this study is to summarize the efficacy and safety of traditional Chinese medicine(TCM)enema in the treatment of ulcerative colitis(UC).The randomized controlled trials on TCM enema intervention in th...The objective of this study is to summarize the efficacy and safety of traditional Chinese medicine(TCM)enema in the treatment of ulcerative colitis(UC).The randomized controlled trials on TCM enema intervention in the treatment of UC were searched in seven databases:PubMed,Embase,Web of Science,CBM,CNKI,Wanfang Database,and VIP Database from January 1,2013 to June 6,2022,and the data were analyzed using RevMan 5.3 software.A total of 18 studies involving 1514 UC patients were included.Meta analysis results showed that compared with conventional Western medicine,Chinese medicine enema had a significant effect on UC,and the clinical effective rate of the experimental group using Chinese medicine enema was 4.45 times that of the control group using conventional Western medicine(odds ratio=4.45,95%confidence interval[3.27,6.06]).Therefore,Chinese medicine enema is effective in the treatment of UC,and can significantly reduce related symptoms.展开更多
Objective:The objective of this study is to comprehensively understand the psychological experience of primiparous women during breastfeeding while dealing with lactating mastitis and to establish a reliable foundatio...Objective:The objective of this study is to comprehensively understand the psychological experience of primiparous women during breastfeeding while dealing with lactating mastitis and to establish a reliable foundation for tailored support measures.Methods:Twenty primiparous mothers from a tertiary hospital in Beijing between January and March 2023 were chosen using purposive sampling for semi-structured interviews.After conducting 20 interviews,data saturation was achieved.The Colaizzi’s seven-step analytical approach was employed to analyze,summarize,and refine the identified themes.Results:Among primiparous women afflicted by lactating mastitis,the primary themes regarding breastfeeding attitudes included three key aspects:(1)uncertainty during the initial diagnosis phase,(2)intricate emotional journey during treatment,and(3)positive psychological outlook during the recovery stage.Conclusion:Primiparous women undergoing lactating mastitis experience substantial physical and psychological strain.It is crucial for medical personnel,family caregivers,and society at large to be attuned to the emotions of these patients.Tailored support measures should be offered to enhance patients’physical and mental well-being and facilitate disease recovery.展开更多
To enhance the high-temperature adaptability of copper-based composite materials and C–C/SiC discs,this article innovatively introduces a method of replacing graphite with sepiolite,resulting in the successful fabric...To enhance the high-temperature adaptability of copper-based composite materials and C–C/SiC discs,this article innovatively introduces a method of replacing graphite with sepiolite,resulting in the successful fabrication of samples with exceptional mechanical and friction properties.The results reveal that moderate incorporation(less 6%)of sepiolite provides a particle reinforcement effect,resulting in an improvement of mechanical properties.Interestingly,the addition of sepiolite causes a change in the traditional saddle-shaped friction curve due to high temperature lubrication.Meanwhile,the primary advantage of sepiolite lies in its superior abrasion resistance,evident in the increased friction coefficient and altered wear mechanisms with higher sepiolite content.The wear resistance is optimal at 200 Km/h(400℃).Particularly,the unique composition of the friction layer(outermost layer:a composite film consisting of B2O3,sepiolite,graphite,and metal oxide films;intermediate layer:metal oxide films)plays a pivotal role in improving friction stability.Finally,there are significant optimizations in the GA algorithm,especially GA-GB model has the best prediction effect on the maximum friction temperature.展开更多
Knowledge of the plasticity of language pathways neurosurgeons to achieve maximum resection wh n patients with low-grade glioma is important for e preserving neurological function. The current study sought to investig...Knowledge of the plasticity of language pathways neurosurgeons to achieve maximum resection wh n patients with low-grade glioma is important for e preserving neurological function. The current study sought to investigate changes in the ventral language pathways in patients with low-grade glioma located in regions likely to affect the dorsal language pathways. The results revealed no significant difference in fractional anisotropy values in the arcuate fasciculus between groups or between hemispheres. However, fractional anisotropy and lateralization index values in the left inferior longitudinal fasciculus and lateralization index values in the left inferior fronto-occpital fasciculus were higher in patients than in healthy subjects. These results indicate plasticity of language pathways in patients with low-grade glioma. The ventral language pathways may perform more functions in patients than in healthy subjects. As such, it is important to protect the ventral language pathways intraoperatively.展开更多
Meloxicam(MLX) is efficient in relieving pain and inflammatory symptoms, which, however, is limited by the poor solubility and gastrointestinal side effects. The objective of this study is to develop a nanocrystal for...Meloxicam(MLX) is efficient in relieving pain and inflammatory symptoms, which, however, is limited by the poor solubility and gastrointestinal side effects. The objective of this study is to develop a nanocrystal formulation to enhance transdermal delivery of MLX. MLX nanocrystals were successfully prepared by the nanoprecipitation technique based on acidbase neutralization. With poloxamer 407 and Tween 80(80/20, w/w) as mixed stabilizers,MLX nanocrystals with particle size of 175 nm were obtained. The crystalline structure of MLX nanocrystals was confirmed by both differential scanning calorimetry and X-ray powder diffractometry. However, the nanoprecipitation process reduced the crystallinity of MLX.Nanocrystals increased both in vitro and in vivo transdermal permeation of MLX compared with the solution and suspension counterparts. Due to the enhanced apparent solubility and dissolution as well as the facilitated hair follicular penetration, nanocrystals present a high and prolonged plasma MLX concentration. And 2.58-and 4.4-fold increase in AUC0 →2 4 h was achieved by nanocrystals comparing with solution and suspension, respectively. In conclusion, nanocrystal is advantageous for transdermal delivery of MLX.展开更多
Modulation recognition has been long investigated in the literature,however,the performance could be severely degraded in multipath fading channels especially for high-order Quadrature Amplitude Modulation(QAM)signals...Modulation recognition has been long investigated in the literature,however,the performance could be severely degraded in multipath fading channels especially for high-order Quadrature Amplitude Modulation(QAM)signals.This could be a critical problem in the broadband maritime wireless communications,where various propagation paths with large differences in the time of arrival are very likely to exist.Specifically,multiple paths may stem from the direct path,the reflection paths from the rough sea surface,and the refraction paths from the atmospheric duct,respectively.To address this issue,we propose a novel blind equalization-aided deep learning(DL)approach to recognize QAM signals in the presence of multipath propagation.The proposed approach consists of two modules:A blind equalization module and a subsequent DL network which employs the structure of ResNet.With predefined searching step-sizes for the blind equalization algorithm,which are designed according to the set of modulation formats of interest,the DL network is trained and tested over various multipath channel parameter settings.It is shown that as compared to the conventional DL approaches without equalization,the proposed method can achieve an improvement in the recognition accuracy up to 30%in severe multipath scenarios,especially in the high SNR regime.Moreover,it efficiently reduces the number of training data that is required.展开更多
基金sponsored by the Natural Science Foundation of Zhejiang Province(LQ22D060002 and LTGC23C190001)Fund of State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products(ZS20190105)+1 种基金General Project of Zhejiang Provincial Department of Education(Y202146257)K.C.Wong Magna Fund of Ningbo University。
文摘Iron deficiency anemia(IDA)is a nutritional deficiency disease with a high incidence rate worldwide.Bioactive peptides are safe and effective,have multiple functions and can serve as potential candidates for alleviating IDA.In this study,the anti-anemia effects of tuna dark muscle peptides were explored in a dietinduced IDA mouse model.The results showed that tuna dark muscle peptides alleviated the IDA phenotype,oxidative stress and iron metabolism.In addition,tuna dark muscle peptides reversed gut microbiota dysbiosis in IDA mice.Furthermore,the transplanted fecal microbiota from tuna dark muscle peptide-treated mice also alleviated IDA symptoms and regulated iron metabolism and the gut microbiota,indicating that the antianemic effects were at least partially mediated by the gut microbiota.Thus,we identified a new and safe prebiotic material to alleviate IDA and provided ideas for the development of peptides.At the same time,these data also provided a theoretical basis for fecal microbiota transplantation to alleviate IDA.
基金This study was supported by a grant from the National Natural Science Foundation of China(81870457).
文摘Background:Acute suppurative terminal cholangitis(ASTC)is rarer than acute obstructive cholangitis and is not well studied.To explore this subtype of acute cholangitis,we described our clinical experience with ASTC.Methods:We performed a retrospective review of patients with ASTC admitted to our center from September 2014 to August 2020.We analyzed their clinical characteristics,including etiology,clinical manifestations,imaging features,treatment and prognosis.Results:A total of 32 ASTC patients were included in the analysis.The majority of the patients had a history of biliary operations,and clinical manifestations were occult and atypical.The positive rate of bacterial culture was 46.9%.All the patients had typical imaging features on computed tomography and magnetic resonance imaging.Treatment with effective antibiotics was provided as soon as diagnosis was established.After treatment,most patients had a good outcome.Elevated levels of total bilirubin,aspartate aminotransferase,procalcitonin and gamma-glutamyltransferase were the characteristics of critically ill patients and were associated with relatively poor prognosis.Conclusions:Our results demonstrated that ASTC should be recognized as a new subtype of acute cholangitis,and that earlier diagnosis and more personalized treatments are needed.
基金supported by Guangxi Health Commission Project [No.Z20200514]Guangxi Science and Technology Base and Talent Project [No.AD22035052]。
文摘Tetanus is the only non-communicable disease among vaccine-preventable infectious diseases.It is caused by an infection with Clostridium tetanus bacterium and is characterized by continuous tonic contraction and paroxysmal spasms of skeletal muscles throughout the body[1].
基金supported by the National Natural Science Foundation of China[NSFC81971934]+2 种基金Guangxi Key Research and Development Program[Guike AB18050022,to HL]National Key R&D Program of China[No.2022YFC2305001]the"13th Five-Year Plan"National Science and Technology Major Project[2018ZX10715-008-002]。
文摘Human immunodeficiency virus(HIV)is a serious public health concern.Globally,1.7 million(1.3–2.1 million)children aged 0–14 were living with HIV at the end of 2021,90%of whom lived in low-and middle-income countries.Acquired Immune Deficiency Syndrome(AIDS)remains the leading cause of mortality among children worldwide.
基金supported in part by the Natural Science Foundation of Xinjiang Uygur Autonomous Region(Grant No.2022D01B186 and No.2022D01B05)。
文摘The attention mechanism can extract salient features in images,which has been proved to be effective in improving the performance of person re-identification(Re-ID).However,most of the existing attention modules have the following two shortcomings:On the one hand,they mostly use global average pooling to generate context descriptors,without highlighting the guiding role of salient information on descriptor generation,resulting in insufficient ability of the final generated attention mask representation;On the other hand,the design of most attention modules is complicated,which greatly increases the computational cost of the model.To solve these problems,this paper proposes an attention module called self-supervised recalibration(SR)block,which introduces both global and local information through adaptive weighted fusion to generate a more refined attention mask.In particular,a special"Squeeze-Excitation"(SE)unit is designed in the SR block to further process the generated intermediate masks,both for nonlinearizations of the features and for constraint of the resulting computation by controlling the number of channels.Furthermore,we combine the most commonly used Res Net-50 to construct the instantiation model of the SR block,and verify its effectiveness on multiple Re-ID datasets,especially the mean Average Precision(m AP)on the Occluded-Duke dataset exceeds the state-of-the-art(SOTA)algorithm by 4.49%.
基金Theme-based research scheme of Hong Kong Research Grant Council(RGC Ref:T13-402/17-N)National Natural Science Foundation of China(No.U1804251)。
文摘After reconstructing the anterior cruciate ligament(ACL),unsatisfactory bone tendon interface healing may often induce tunnel enlargement at the early healing stage.With good biological features and high formability,Magnesium-Zinc-Gadolinium(ZG21)wires are developed to bunch the tendon graft for matching the bone tunnel during transplantation.Microstructure,tensile strength,degradation,and cytotoxicity of ZG21 wire are evaluated.The rabbit model is used for assessing the biological effects of ZG21 wire by Micro-CT,histology,and mechanical test.The SEM/EDS,immunochemistry,and in vitro assessments are performed to investigate the underlying mechanism.Material tests demonstrate the high formability of ZG21 wire as surgical suture.Micro-CT shows ZG21 wire degradation accelerates tunnel bone formation,and histologically with earlier and more fibrocartilage regeneration at the healing interface.The mechanical test shows higher ultimate load in the ZG21 group.The SEM/EDS presents ZG21 wire degradation triggered calcium phosphate(Ca-P)deposition.IHC results demonstrate upregulation of Wnt3a,BMP2,and VEGF at the early phase and TGFβ3 and Type II collagen at the late phase of healing.In vitro tests also confirmed the Ca-P in the metal extract could elevate the expression of Wnt3a,βcatenin,ocn and opn to stimulate osteogenesis.Ex vivo tests of clinical samples indicated suturing with ZG21 wire did not weaken the ultimate loading of human tendon tissue.In conclusion,the ZG21 wire is feasible for tendon graft bunching.Its degradation products accelerated intra-tunnel endochondral ossification at the early healing stage and therefore enhanced bone-tendon interface healing in ACL reconstruction.
文摘The objective of this study is to summarize the efficacy and safety of traditional Chinese medicine(TCM)enema in the treatment of ulcerative colitis(UC).The randomized controlled trials on TCM enema intervention in the treatment of UC were searched in seven databases:PubMed,Embase,Web of Science,CBM,CNKI,Wanfang Database,and VIP Database from January 1,2013 to June 6,2022,and the data were analyzed using RevMan 5.3 software.A total of 18 studies involving 1514 UC patients were included.Meta analysis results showed that compared with conventional Western medicine,Chinese medicine enema had a significant effect on UC,and the clinical effective rate of the experimental group using Chinese medicine enema was 4.45 times that of the control group using conventional Western medicine(odds ratio=4.45,95%confidence interval[3.27,6.06]).Therefore,Chinese medicine enema is effective in the treatment of UC,and can significantly reduce related symptoms.
基金supported by the 2022 Capital’s Funds for Health Improvement and Research(CFH)(2022-2-4202).
文摘Objective:The objective of this study is to comprehensively understand the psychological experience of primiparous women during breastfeeding while dealing with lactating mastitis and to establish a reliable foundation for tailored support measures.Methods:Twenty primiparous mothers from a tertiary hospital in Beijing between January and March 2023 were chosen using purposive sampling for semi-structured interviews.After conducting 20 interviews,data saturation was achieved.The Colaizzi’s seven-step analytical approach was employed to analyze,summarize,and refine the identified themes.Results:Among primiparous women afflicted by lactating mastitis,the primary themes regarding breastfeeding attitudes included three key aspects:(1)uncertainty during the initial diagnosis phase,(2)intricate emotional journey during treatment,and(3)positive psychological outlook during the recovery stage.Conclusion:Primiparous women undergoing lactating mastitis experience substantial physical and psychological strain.It is crucial for medical personnel,family caregivers,and society at large to be attuned to the emotions of these patients.Tailored support measures should be offered to enhance patients’physical and mental well-being and facilitate disease recovery.
基金the National Key Research and Development Program of China(Grant No.2021YFB3703803)National Natural Science Foundation of China(Grant No.52075555)for their financial support.
文摘To enhance the high-temperature adaptability of copper-based composite materials and C–C/SiC discs,this article innovatively introduces a method of replacing graphite with sepiolite,resulting in the successful fabrication of samples with exceptional mechanical and friction properties.The results reveal that moderate incorporation(less 6%)of sepiolite provides a particle reinforcement effect,resulting in an improvement of mechanical properties.Interestingly,the addition of sepiolite causes a change in the traditional saddle-shaped friction curve due to high temperature lubrication.Meanwhile,the primary advantage of sepiolite lies in its superior abrasion resistance,evident in the increased friction coefficient and altered wear mechanisms with higher sepiolite content.The wear resistance is optimal at 200 Km/h(400℃).Particularly,the unique composition of the friction layer(outermost layer:a composite film consisting of B2O3,sepiolite,graphite,and metal oxide films;intermediate layer:metal oxide films)plays a pivotal role in improving friction stability.Finally,there are significant optimizations in the GA algorithm,especially GA-GB model has the best prediction effect on the maximum friction temperature.
基金supported by the National Natural Science Foundation of China, No. 31040039the Natural Science Foundation of Beijing, No. 7102145the Military Clinical High-Tech Foundation, No. 2010gxjso94
文摘Knowledge of the plasticity of language pathways neurosurgeons to achieve maximum resection wh n patients with low-grade glioma is important for e preserving neurological function. The current study sought to investigate changes in the ventral language pathways in patients with low-grade glioma located in regions likely to affect the dorsal language pathways. The results revealed no significant difference in fractional anisotropy values in the arcuate fasciculus between groups or between hemispheres. However, fractional anisotropy and lateralization index values in the left inferior longitudinal fasciculus and lateralization index values in the left inferior fronto-occpital fasciculus were higher in patients than in healthy subjects. These results indicate plasticity of language pathways in patients with low-grade glioma. The ventral language pathways may perform more functions in patients than in healthy subjects. As such, it is important to protect the ventral language pathways intraoperatively.
基金financially supported by Natural Science Foun-dation of Shanghai(16ZR1403500)
文摘Meloxicam(MLX) is efficient in relieving pain and inflammatory symptoms, which, however, is limited by the poor solubility and gastrointestinal side effects. The objective of this study is to develop a nanocrystal formulation to enhance transdermal delivery of MLX. MLX nanocrystals were successfully prepared by the nanoprecipitation technique based on acidbase neutralization. With poloxamer 407 and Tween 80(80/20, w/w) as mixed stabilizers,MLX nanocrystals with particle size of 175 nm were obtained. The crystalline structure of MLX nanocrystals was confirmed by both differential scanning calorimetry and X-ray powder diffractometry. However, the nanoprecipitation process reduced the crystallinity of MLX.Nanocrystals increased both in vitro and in vivo transdermal permeation of MLX compared with the solution and suspension counterparts. Due to the enhanced apparent solubility and dissolution as well as the facilitated hair follicular penetration, nanocrystals present a high and prolonged plasma MLX concentration. And 2.58-and 4.4-fold increase in AUC0 →2 4 h was achieved by nanocrystals comparing with solution and suspension, respectively. In conclusion, nanocrystal is advantageous for transdermal delivery of MLX.
基金the National Natural Science Foundation of China under Grant 61771264,61801114,61501264,61771286the Nantong University-Nantong Joint Research Center for Intelligent Information Technology under Grant No.KFKT2017B01,KFKT2017A04the Natural Science Foundation of Jiangsu Province under Grant BK20170688.
文摘Modulation recognition has been long investigated in the literature,however,the performance could be severely degraded in multipath fading channels especially for high-order Quadrature Amplitude Modulation(QAM)signals.This could be a critical problem in the broadband maritime wireless communications,where various propagation paths with large differences in the time of arrival are very likely to exist.Specifically,multiple paths may stem from the direct path,the reflection paths from the rough sea surface,and the refraction paths from the atmospheric duct,respectively.To address this issue,we propose a novel blind equalization-aided deep learning(DL)approach to recognize QAM signals in the presence of multipath propagation.The proposed approach consists of two modules:A blind equalization module and a subsequent DL network which employs the structure of ResNet.With predefined searching step-sizes for the blind equalization algorithm,which are designed according to the set of modulation formats of interest,the DL network is trained and tested over various multipath channel parameter settings.It is shown that as compared to the conventional DL approaches without equalization,the proposed method can achieve an improvement in the recognition accuracy up to 30%in severe multipath scenarios,especially in the high SNR regime.Moreover,it efficiently reduces the number of training data that is required.
