27 research outputs found
Low Correlation Interference OFDM-NLFM Waveform Design for MIMO Radar Based on Alternating Optimization.
The OFDM chirp signal is suitable for MIMO radar applications due to its large time-bandwidth product, constant time-domain, and almost constant frequency-domain modulus. Particularly, by introducing the time-frequency structure of the non-linear frequency modulation (NLFM) signal into the design of an OFDM chirp waveform, a new OFDM-NLFM waveform with low peak auto-correlation sidelobe ratio (PASR) and peak cross-correlation ratio (PCCR) is obtained. IN-OFDM is the OFDM-NLFM waveform set currently with the lowest PASR and PCCR. Here we construct the optimization model of the OFDM-NLFM waveform set with the objective function being the maximum of the PASR and PCCR. Further, this paper proposes an OFDM-NLFM waveform set design algorithm inspired by alternating optimization. We implement the proposed algorithm by the alternate execution of two sub-algorithms. First, we keep both the sub-chirp sequence code matrix and sub-chirp rate plus and minus (PM) code matrix unchanged and use the particle swarm optimization (PSO) algorithm to obtain the optimal parameters of the NLFM signal's time-frequency structure (NLFM parameters). Next, we keep current optimal NLFM parameters unchanged, and optimize the sub-chirp sequence code matrix and sub-chirp rate PM code matrix using the block coordinate descent (BCD) algorithm. The above two sub-algorithms are alternately executed until the objective function converges to the optimal solution. The results show that the PASR and PCCR of the obtained OFDM-NLFM waveform set are about 5 dB lower than that of the IN-OFDM
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Prevalence and related factors of epilepsy in children and adolescents with cerebral palsy: a systematic review and meta-analysis
Objective: To study the worldwide prevalence and associated factors of epilepsy in children and adolescents with Cerebral Palsy (CP) and to analyze the differences between various subgroups.
Method: We identified all potential studies on the prevalence of epilepsy in children and adolescents with CP from PubMed, Web of Science, and Embase. The search time was from the establishment of the database to November 2022. Randomized effects meta-analysis models were used to calculate the prevalence of epilepsy in CP. Subgroup analysis and meta-regression were utilized to further explore heterogeneity between articles and prevalence disparities between subgroups. The funnel plot and Eggerâs test were used to investigate potential publication bias. Results: Seventy-two articles, comprising 53,969 children and adolescents with CP, were included in this study. The results indicated a total epilepsy prevalence of 38.0% (95% CI: 34.8%â41.2%) in CP. The prevalence of epilepsy was 46.4% (95% CI: 41.4%â51.5%) in clinical sample-based studies and 31.6% (95% CI: 28.7%â34.5%) in population-based studies. Meta-regression demonstrated that the sample source, neonatal seizure, family history of epilepsy, EEG or cranial imaging abnormalities, intellectual/cognitive impairment, and topographical types of CP were heterogeneous contributors to the epilepsy prevalence in CP. Conclusion: Approximately one-third of children and adolescents with CP have epilepsy, and the sample source can significantly impact the total prevalence of epilepsy. Neonatal seizures, family history of epilepsy, EEG abnormalities, cranial imaging abnormalities, severe intellectual disability, and quadriplegia may be contributing factors to epilepsy comorbid in CP. Further study is required to verify the strength of these associations with epilepsy. This study aids in identifying the clinical characteristics of young people with CP at risk of developing epilepsy, which may assist clinicians in the early prevention and diagnosis of epilepsy within this population
Tumorâderived exosomal miRâ148bâ3p mediates M2 macrophage polarization via TSC2/mTORC1 to promote breast cancer migration and invasion
Abstract Background Emerging evidence has revealed that tumorâassociated macrophages (TAMs) and exosomes play a crucial role in the microenvironment for tumor growth. However, the mechanisms through which exosomal miRNAs modulate TAMs and tumor development in breast cancer are not fully understood. Methods We constructed a macrophage model and an indirect coculture system consist of breast cancer cells and macrophages. Exosomes were isolated from BC cells culture supernatant and identified by transmission electron microscopy, Western blot and Nanosight LM10 system. The expression of miRâ148bâ3p in exosomes was determined by qRTâPCR and the effect of exosomal miRâ148bâ3p on macrophage polarization was measured using qRTâPCR and ELISA. The proliferation, migration and invasion of BC cells were estimated by EdU, wound healing assay and transwell assay. We employed bioinformatics, luciferase reporter assay and Western blot to identify the target gene of miRâ148bâ3p. Western blot was used to clarify the mechanism of exosomal miRâ148bâ3p mediated the crosstalk between BC cells and M2 macrophages. Results Cancerâderived exosomes could induce M2 polarization of macrophages, which promoted the migration and invasion of breast cancer cells. We found that exosomal miRâ148bâ3p was overexpressed in breast cancer cellâderived exosomes and correlated with lymph node metastasis, late tumor stage and worse prognosis. Upregulated miRâ148bâ3p expression in exosomes modulated macrophage polarization by targeting TSC2, which promoted the proliferation and might affect migration and invasion of breast cancer cells. Interestingly, we found that exosomal miRâ148bâ3p could induce M2 macrophage polarization via the TSC2/mTORC1 signaling pathway in breast cancer. Conclusion Overall, our study elucidated that miRâ148bâ3p could be transported by exosomes from breast cancer cells to surrounding macrophages and induced M2 polarization by targeting TSC2, providing novel insights for breast cancer therapy
Efficacy and safety of Ding-Kun-Dan for female infertility patients with predicted poor ovarian response undergoing in vitro fertilization/intracytoplasmic sperm injection: study protocol for a randomized controlled trial
Abstract Background Women undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) who have a predicted poor ovarian response (POR) present a challenge for reproductive medicine specialists. Traditional Chinese medicine (TCM) is commonly used in China for such patients, in the belief that it will improve the ovarian response and ultimately increase pregnancy rates. However, there is a lack of high-quality evidence about the effect of TCM on improving ovarian response in such patients. The purpose of this study is to evaluate ongoing viable pregnancy rate at 12 weeksâ gestation and related indicators of ovarian response in fertile women who have a predicted poor ovarian response having immediate versus delayed IVF/ICSI after 3 months of Ding-Kun-Dan (DKD) pre-treatment. Methods/design This study is a multicenter, randomized controlled, parallel-group, phase III, superiority clinical trial. Two hundred and seventy-eight eligible female infertility patients with POR will be included in the study and randomly allocated into an immediate treatment group and a DKD group in a 1:1 ratio. Both groups will receive IVF or ICSI as a standard treatment while in the DKD group, a commercially available Chinese medicine, DKD, will be administrated for 3 months before the IVF/ICSI cycle starts. The primary outcome of the study is the ongoing pregnancy rate at 12 weeksâ gestation. The secondary outcomes include total gonadotropin dosage, duration of stimulation, estradiol (E2) and progesterone (P) levels on human chorionic gonadotropin (hCG) trigger day, cycle cancellation rate, number of oocytes retrieved, high-quality embryo rate, biochemical pregnancy rate, the change of serum anti-MĂŒllerian hormone (AMH), follicle-stimulating hormone (FSH), and E2 levels and all side effects, safety outcomes, and any adverse events. The protocol was approved by the Ethics Committee of the First Teaching Hospital of Tianjin university of TCM (approval no. TYLL2017[K] 004). Discussion IVF/ICSI is increasingly used to treat couples desiring a baby. Many of these women will have poor ovarian function. In China, DKD is commonly used for these patients prior to undergoing IVF/ICSI. There is no effective treatment for poor ovarian response in Western medicine currently. It is important, therefore, to undertake this randomized control trial to determine whether DKD is effective or not. Trial registration Chinese Clinical Trial Registry, ID: ChiCTR-IOR-17011697. Registered on 19 June 2017
HLA polymorphism and susceptibility to end-stage renal disease in Cantonese patients awaiting kidney transplantation.
BACKGROUND: End-Stage Renal Disease (ESRD) is a worldwide public health problem. Currently, many genome-wide association studies have suggested a potential association between human leukocyte antigen (HLA) and ESRD by uncovering a causal relationship between HLA and glomerulonephritis. However, previous studies, which investigated the HLA polymorphism and its association with ESRD, were performed with the modest data sets and thus might be limited. On the other hand, few researches were conducted to tackle the Chinese population with ESRD. Therefore, this study aims to detect the susceptibilities of HLA polymorphism to ESRD within the Cantonese community, a representative southern population of China. METHODS: From the same region, 4541 ESRD patients who were waiting for kidney transplantation and 3744 healthy volunteer bone marrow donors (controls) were randomly chosen for this study. Polymerase chain reaction-sequence specific primer method was used to analyze the HLA polymorphisms (including HLA-A, HLA-B and HLA-DRB1 loci) in both ESRD patients and controls. The frequencies of alleles at these loci and haplotypes were compared between ESRD patients and controls. RESULTS: A total of 88 distinct HLA alleles and 1361 HLA A-B-DRB1 haplotypes were detected. The frequencies of five alleles, HLA-A*24, HLA-B*55, HLA-B*54, HLA-B*40(60), HLA-DRB1*04, and one haplotype (HLA-A*11-B*27-DRB1*04) in ESRD patients are significantly higher than those in the controls, respectively. CONCLUSIONS: Five HLA alleles and one haplotype at the HLA-A, HLA-B and HLA-DRB1 loci appear to be associated with ESRD within the Cantonese population
Effects of Mini-Basketball Training Program on Social Communication Impairment and Executive Control Network in Preschool Children with Autism Spectrum Disorder
This study evaluated the effect of a 12-week mini-basketball training program (MBTP) on social communication (SC) and the executive control network (ECN) in preschool children with autism spectrum disorders (ASD). We finally assigned 30 preschool children with ASD to an experiment group (n = 15, 12 males, 3 females) or a control group (n = 15, 13 males, 2 females). The experiment group participated in a 12-week MBTP (40-min sessions per day, 5 days a week), while the control group only received the institutional routine behavioral rehabilitation intervention. The SC of preschool children with ASD was measured using the Social Responsiveness Scale, Second Edition (SRS-2), whereas functional connectivity (FC) of the ECN was assessed using resting-state functional magnetic resonance imaging (rs-fMRI) at pre-and post-test. Our results showed that SC exhibited significant improvement in the intervention group, especially in SRS-2 total score, social cognition, and social communication. We found significantly enhanced functional connectivity between the right cerebellum and left inferior frontal gyrus in the experimental group, while functional connectivity between the left middle temporal gyrus and right cerebellum were decreased in the control group. Furthermore, there were no significant correlations between the change in SC scores and FC of the ECN. Altogether, this study provides valuable insights that a 12-week MBTP improves SC and functional connectivity of the ECN in preschool children with ASD. We further inferred that neural mechanisms might be associated with changing the ECN of preschool ASD children caused by the 12-week MBTP
Frequency of the susceptible three-locus HLA haplotypes in ESRD patients and controls (ordered by statistical significance for susceptible haplotypes).
a<p>Listed are only the top 5% of all the HLA-A-B-DRB1 haplotypes with significant uncorrected P-value.</p>b<p>Using Fisher exact test.</p>c<p>P values were adjusted by Bonferroni method. Multiplicative factor was used for each haplotype.</p
Additional file 1: of Efficacy and safety of Ding-Kun-Dan for female infertility patients with predicted poor ovarian response undergoing in vitro fertilization/intracytoplasmic sperm injection: study protocol for a randomized controlled trial
SPIRIT Checklist. The SPIRIT Checklist document. (DOC 135ĂÂ kb
Numbers of HLA-A, -B and -DRB1 alleles in ESRD patients and controls.
<p>Numbers of HLA-A, -B and -DRB1 alleles in ESRD patients and controls.</p
Allele frequencies at HLA-A, -B and -DRB1 loci in ESRD patients and controls (ordered by statistical significance for each locus).
a<p>Listed are only the most frequent (top 20%) alleles for each HLA locus in the ESRD patients and controls, respectively.</p>b<p>Using Fisher exact test.</p>c<p>P values were adjusted by Bonferroni method. Multiplicative factor was used for each allele.</p