Adaptive decision threshold algorithm based on a sliding window to reduce BER of free-space optical communication systems.

Free-space optical communication (FSOC) systems face susceptibility to several factors, such as transmission distance, atmospheric turbulence, and alignment errors. These elements contribute to fluctuations in the signal strength reaching the receiver. The resultant signal fluctuations can result in misjudgments and an elevated bit error rate (BER). This paper proposes an adaptive decision threshold algorithm based on a sliding window (ADTSW). By estimating received signal parameters and delimiting the amplitude interval, the algorithm ensures that the decision threshold tracks signal fluctuations, thereby reducing signal misjudgment. The effectiveness of the algorithm is validated through simulations and experimentation. When the signal peak-to-peak value fluctuates, simulation results demonstrate that the proposed algorithm achieves a 1-order-of-magnitude reduction in BER compared to the traditional fixed decision threshold (FDT) method. Under the influence of weak atmospheric turbulence with different scintillation variance, both simulation and experimentation indicate a 1-order-of-magnitude reduction in BER compared to the FDT method. The ADTSW algorithm proves its capability in minimizing misjudgments, thereby effectively reducing BER and improving communication quality.

Triterpenoids from Juglans sigillata and their anti-inflammatory and radical scavenging activity.

A phytochemical investigation on 90% methanol extract from the leaves of Juglans sigillata led to the isolation of three new triterpenoids, jugsigiloids A-C (1-3). Structural elucidation of all the compounds were performed by spectral methods such as 1 D and 2 D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. The isolated components were evaluated in vitro for anti-inflammatory activities against COX-1 and COX-2 and radical scavenging potential using DPPH test. As a result, triterpenoid 1 exhibited selective inhibition on COX-2 (93.2%) at the concentration of 100 µM and significant DPPH scavenging activity (IC50 = 41.6 µM) comparable with positive control Trolox (IC50 = 42.8 µM).

150 Gbit/s 1 km high-sensitivity FSO communication outfield demonstration based on a soliton microcomb.

A high-sensitivity and large-capacity free space optical (FSO) communication scheme based on the soliton microcomb (SMC) is proposed. Using ultra-large bandwidth stabilized SMC with a frequency interval of 48.97 GHz as the laser source, 60 optical wavelengths modulated by 2.5 Gbit/s 16-Pulse position modulation (PPM) are transmitted in parallel. A corresponding outfield high-sensitivity 150 Gbit/s FSO communication experiment based on the SMC was carried out with 1 km space distance. Our experimental results show that the best sensitivity of the single comb wavelength which has higher OSNR can reach -52.62 dBm, and the difference is only 1.38 dB from the theoretical limit under the BER of 1 × 10-3 without forward error correction (FEC). In addition, at BER of 1 × 10-3, 16-PPM has a higher received sensitivity of 6.73dB and 3.72dB compared to on-off keying (OOK) and differential phase shift keying (DPSK) respectively. Meanwhile, taking the advantage of multi-channel SMC, 60 × 2.5 Gbit/s can achieve 150 Gbit/s large-capacity free-space transmission. For comparison, commercially available single-wavelength laser based FSO communication system have also been performed in the outfield. The outfield experimental results demonstrated the feasibility of high-sensitivity, large-capacity PPM FSO communication based on SMCs and provided a new perspective for the future development of large-capacity, long-haul FSO communication.

Circulating neuropeptide Y as a biomarker in postoperative atrial fibrillation cases administered off-pump coronary bypass Graft surgery.

Background and aims: Postoperative atrial fibrillation (POAF) is considered the most prevalent irregular heart rhythm after heart surgery. The cardiac autonomic nervous system significantly affects POAF, and neuropeptide Y (NPY), an abundant neuropeptide in the cardiovascular system, is involved in this autonomic regulation. The current work aimed to examine the potential association of NPY with POAF in individuals administered isolated off-pump coronary artery bypass grafting. Methods: From January 1 to May 31, 2020, we examined consecutive cases administered successful isolated off-pump coronary artery bypass grafting with no previously diagnosed atrial fibrillation (AF). Clinical characteristics and plasma samples were collected before surgery. NPY was quantified by enzyme-linked immunosorbent assay (ELISA) in peripheral blood, and POAF cases were identified through a 7-day Holter monitoring. Results: Among 120 cases with no previously diagnosed AF, 33 (27.5 %) developed POAF during hospitalization. Median NPY levels were markedly elevated in the POAF group in comparison with the sinus rhythm group (31.72 vs. 27.95, P = 0.014). Multivariable logistic regression analysis revealed age (OR = 1.135, 95%CI 1.054-1.223; P = 0.001), left atrial size (OR = 1.136, 95%CI 1.004-1.285; P = 0.043), and NPY levels in peripheral blood (OR = 1.055, 95%CI 1.002-1.111; p = 0.041) independently predicted POAF. Additionally, NPY levels were positively correlated with high-frequency (HF) (r = 0.2774, P = 0.0022) and low-frequency (LF) (r = 0.2095, P = 0.0217) components of heart rate variability. Conclusion: In summary, this study demonstrates an association between elevated NPY levels in peripheral blood before surgery and POAF occurrence.

Preparation of starch-palmitic acid complexes by three different starches: A comparative study using the method of heating treatment and autoclaving treatment.

Recent research emphasizes the growing importance of starch-lipid complexes due to their anti-digestibility ability, prompting a need to explore the impact of different starch sources and preparation methods on their properties. In this study, starch-palmitic acid (PA) complexes were prepared by three different starches including Tartary buckwheat starch (TBS), potato starch (PTS), and pea starch (PS) by heating treatment (HT) and autoclaving treatment (AT), respectively, and their physicochemical property and in vitro digestibility were systematically compared. The formation of the starch-PA complex was confirmed through various characterization techniques, including scanning electron microscopy, differential scanning calorimetry, Fourier transform infrared spectroscopy, and X-ray diffraction. Among the complexes, the PTS-PA complex exhibited the highest complexation index over 80 %, while the PS-PA complex had the lowest rapid digestible starch content (56.49-59.42 %). Additionally, the complexes prepared by AT exhibited higher resistant starch content (41.95-32.46 %) than those prepared by HT (31.42-32.49 %), while the complexes prepared by HT held better freeze-thaw stability and hydration ability than those prepared by AT. This study highlights the important role of starch sources in the physicochemical and digestibility properties of starch-lipid complex and the potential application of AT in the preparation of novel resistant starch.

Robust Artificial Intelligence Tool for Atrial Fibrillation Diagnosis: Novel Development Approach Incorporating Both Atrial Electrograms and Surface ECG and Evaluation by Head-to-Head Comparison With Hospital-Based Physician ECG Readers.

BACKGROUND: Atrial fibrillation (AF) increases risk of embolic stroke, and in postoperative patients, increases cost of care. Consequently, ECG screening for AF in high-risk patients is important but labor-intensive. Artificial intelligence (AI) may reduce AF detection workload, but AI development presents challenges. METHODS AND RESULTS: We used a novel approach to AI development for AF detection using both surface ECG recordings and atrial epicardial electrograms obtained in postoperative cardiac patients. Atrial electrograms were used only to facilitate establishing true AF for AI development; this permitted the establishment of an AI-based tool for subsequent AF detection using ECG records alone. A total of 5 million 30-second epochs from 329 patients were annotated as AF or non-AF by expert ECG readers for AI training and validation, while 5 million 30-second epochs from 330 different patients were used for AI testing. AI performance was assessed at the epoch level as well as AF burden at the patient level. AI achieved an area under the receiver operating characteristic curve of 0.932 on validation and 0.953 on testing. At the epoch level, testing results showed means of AF detection sensitivity, specificity, negative predictive value, positive predictive value, and F1 (harmonic mean of positive predictive value and sensitivity) as 0.970, 0.814, 0.976, 0.776, and 0.862, respectively, while the intraclass correlation coefficient for AF burden detection was 0.952. At the patient level, AF burden sensitivity and positive predictivity were 96.2% and 94.5%, respectively. CONCLUSIONS: Use of both atrial electrograms and surface ECG permitted development of a robust AI-based approach to postoperative AF recognition and AF burden assessment. This novel tool may enhance detection and management of AF, particularly in patients following operative cardiac surgery.

High Fat-to-Muscle Ratio Was Associated with Increased Clinical Severity in Patients with Abdominal Trauma.

Overweight and moderate obesity confer a survival benefit in chronic diseases such as coronary artery disease and chronic kidney disease, which has been termed the "obesity paradox". However, whether this phenomenon exists in trauma patients remains controversial. We performed a retrospective cohort study in abdominal trauma patients admitted to a Level I trauma center in Nanjing, China between 2010 and 2020. In addition to the traditional body mass index (BMI) based measures, we further examined the association between body composition-based indices with clinical severity in trauma populations. Body composition indices including skeletal muscle index (SMI), fat tissue index (FTI), and total fat-to-muscle ratio (FTI/SMI) were measured using computed tomography. Our study found that overweight was associated with a four-fold risk of mortality (OR, 4.47 [95% CI, 1.40-14.97], p = 0.012) and obesity was associated with a seven-fold risk of mortality (OR, 6.56 [95% CI, 1.07-36.57], p = 0.032) compared to normal weight. Patients with high FTI/SMI had a three-fold risk of mortality (OR, 3.06 [95% CI, 1.08-10.16], p = 0.046) and double the risk of an intensive care unit length of stay ≥ 5 d (OR, 1.75 [95% CI, 1.06-2.91], p = 0.031) compared to patients with low FTI/SMI. The obesity paradox was not observed in abdominal trauma patients, and high FTI/SMI ratio was independently associated with increased clinical severity.

Subcutaneous Adipose Tissue Is Associated with Acute Kidney Injury after Abdominal Trauma Based on the Generalized Propensity Score Approach: A Retrospective Cohort Study.

INTRODUCTION: Obesity is associated with an increased risk of acute kidney injury (AKI) after trauma. However, the associations between different adipose tissue depots and AKI remain unknown. Our study aimed to quantify the effect of abdominal adiposity on AKI in trauma patients. METHODS: We performed a retrospective cohort study of abdominal trauma patients who were admitted to our hospital from January 2010 to March 2020. Abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) were measured at the level of the third lumbar vertebra using computed tomography. Causal modeling based on the generalized propensity score was used to quantify the effects of body mass index (BMI), VAT, and SAT on AKI. RESULTS: Among 324 abdominal trauma patients, 67 (20.68%) patients developed AKI. Patients with AKI had higher BMI (22.46 kg/m2 vs. 22.04 kg/m2, p = 0.014), higher SAT areas (89.06 cm2 vs. 83.39 cm2, p = 0.151), and higher VAT areas (140.02 cm2 vs. 91.48 cm2, p = 0.001) than those without AKI. By using causal modeling, we found that the risk of developing AKI increased by 8.3% (p = 0.001) and 4.8% (p = 0.022) with one unit increase in BMI (per 1 kg/m2) and ten units increase in SAT (per 10 cm2), respectively. However, VAT did not show a significant association with AKI (p = 0.327). CONCLUSION: SAT, but not VAT, increased the risk of AKI among abdominal trauma patients. Measurement of SAT might help identify patients at higher risk of AKI.

Gut Microbiota in Patients with Postoperative Atrial Fibrillation Undergoing Off-Pump Coronary Bypass Graft Surgery.

BACKGROUND: Post-operative atrial fibrillation (POAF) is one of the most common complications of cardiac surgery. However, the underlying mechanism is not well understood. Alterations in the gut microbiota are associated with the development of atrial fibrillation (AF). The aim of this study was to explore the relationship between gut microbiota and POAF. METHODS: Fecal samples were collected before surgery from 45 patients who underwent coronary artery bypass grafting with POAF and 90 matched patients without POAF (1:2). 16S rRNA sequencing was used to detect the microbiome profiles of 45 POAF patients and 89 matched patients (one sample in the no-POAF group was deleted owing to low quality after sequencing). Plasma 25-hydroxy vitamin D level was measured by ELISA. RESULTS: Compared to the patients without POAF, gut microbiota composition was remarkably changed in the patients with POAF, with an increase in Lachnospira, Acinetobacter, Veillonella and Aeromonas, and a decrease in Escherichia-Shigella, Klebsiella, Streptococcus, Brevundimonas and Citrobacter. Furthermore, plasma 25-hydroxy vitamin D levels were decreased in POAF patients and negatively correlated with an abundance of Lachnospira. CONCLUSIONS: The gut microbiota composition between patients with and without POAF is significantly different, implying that gut microbiota may play a role in the pathogenesis of POAF. Further studies are needed to fully clarify the role of gut microbiota in the initiation of AF.

The impact of multi-level interventions on the second-wave SARS-CoV-2 transmission in China.

BACKGROUND: A re-emergence of COVID-19 occurred in the northeast of China in early 2021. Different levels of non-pharmaceutical interventions, from mass testing to city-level lockdown, were implemented to contain the transmission of SARS-CoV-2. Our study is aimed to evaluate the impact of multi-level control measures on the second-wave SARS-CoV-2 transmission in the most affected cities in China. METHODS: Five cities with over 100 reported COVID-19 cases within one month from Dec 2020 to Feb 2021 were included in our analysis. We fitted the exponential growth model to estimate basic reproduction number (R0), and used a Bayesian approach to assess the dynamics of the time-varying reproduction number (Rt). We fitted linear regression lines on Rt estimates for comparing the decline rates of Rt across cities, and the slopes were tested by analysis of covariance. The effect of non-pharmaceutical interventions (NPIs) was quantified by relative Rt reduction and statistically compared by analysis of variance. RESULTS: A total of 2,609 COVID-19 cases were analyzed in this study. We estimated that R0 all exceeded 1, with the highest value of 3.63 (1.36, 8.53) in Haerbin and the lowest value of 2.45 (1.44, 3.98) in Shijiazhuang. Downward trends of Rt were found in all cities, and the starting time of Rt < 1 was around the 12th day of the first local COVID-19 cases. Statistical tests on regression slopes of Rt and effect of NPIs both showed no significant difference across five cities (P = 0.126 and 0.157). CONCLUSION: Timely implemented NPIs could control the transmission of SARS-CoV-2 with low-intensity measures for places where population immunity has not been established.

Blockade of the Notch Signaling Pathway Promotes M2 Macrophage Polarization to Suppress Cardiac Fibrosis Remodeling in Mice With Myocardial Infarction.

Myocardial infarction (MI) is regarded as a serious ischemic heart disease on a global level. The current study set out to explore the mechanism of the Notch signaling pathway in the regulation of fibrosis remodeling after the occurrence of MI. First, experimental mice were infected with recombination signal binding protein J (RBP-J) shRNA and empty adenovirus vector, followed by the establishment of MI mouse models and detection of cardiac function. After 4 weeks of MI, mice in the sh-RBP-J group were found to exhibit significantly improved cardiac function relative to the sh-NC group. Moreover, knockdown of RBP-J brought about decreased infarct area, promoted cardiac macrophages M2 polarization, reduced cardiac fibrosis, and further decreased transcription and protein expressions of inflammatory factors and fibrosis-related factors. Furthermore, downregulation of cylindromatosis (CYLD) using si-CYLD reversed the results that knockdown of RBP-J inhibited fibrogenesis and the release of inflammatory factors. Altogether, our findings indicated that the blockade of Notch signaling promotes M2 polarization of cardiac macrophages and improves cardiac function by inhibiting the imbalance of fibrotic remodeling after MI.

Calcium-Induced Autonomic Denervation in Patients With Post-Operative Atrial Fibrillation.

BACKGROUND: Post-operative atrial fibrillation (POAF) is associated with worse long-term cardiovascular outcomes. OBJECTIVES: This study hypothesized that injecting calcium chloride (CaCl2) into the major atrial ganglionated plexi (GPs) during isolated coronary artery bypass grafting (CABG) can reduce the incidence of POAF by calcium-induced autonomic neurotoxicity. METHODS: This proof-of-concept study randomized 200 patients undergoing isolated, off-pump CABG to CaCl2 (n = 100) or sodium chloride (sham, n = 100) injection. Two milliliters of CaCl2 (5%) or sodium chloride (0.9%) was injected into the 4 major atrial GPs during CABG. All patients received 7-day continuous telemetry and Holter monitoring. The primary outcome was incidence of POAF (≥30 s) in 7 days. Secondary outcomes included length of hospitalization, POAF burden, average ventricular rate during AF, plasma level of inflammatory markers, and actionable antiarrhythmic therapy to treat POAF. RESULTS: The POAF incidence was reduced from 36% to 15% (hazard ratio: 0.366; 95% confidence interval: 0.211 to 0.635; p = 0.001). Length of hospitalization did not differ between the 2 groups. POAF burden (first 7 post-operative days), the use of amiodarone or esmolol, and the incidence of atrial couplets and nonsustained atrial tachyarrhythmias were significantly reduced in the CaCl2 group. Heart rate variability data showed a decrease in both high-frequency and low-frequency power in the CaCl2 group with a preserved low-frequency/high-frequency ratio, suggesting that the sympathetic/parasympathetic balance was not perturbed by CaCl2 injection. CONCLUSIONS: Injection of CaCl2 into the 4 major atrial GPs reduced the POAF hazard by 63%. Inhibition of GP function by Ca-mediated neurotoxicity may underlie the therapeutic effect. (Calcium Autonomic Denervation Prevents Postoperative Atrial Fibrillation; ChiCTR1800019276).

Microplastic (1 and 5 µm) exposure disturbs lifespan and intestine function in the nematode Caenorhabditis elegans.

As an emerging environmental pollutant, microplastics (MPs) are increasingly viewed as a serious health concern to terrestrial and aquatic ecosystems. However, previous toxicological studies examining MPs on freshwater and terrestrial organisms provide contradictory results, possibly due to few investigations at environmentally relevant concentrations. Here, the nematode Caenorhabditis elegans (C. elegans), a model organisms with both aquatic and terrestrial free-living forms, was employed to investigate the effects of 1 and 5 µm MPs (107-1010 particles/m2) on the intake, lifespan, defecation rhythm, defecation-related neurons and transcriptional expression of related genes (skn-1, mkk-4, pmk-1, cpr-1 and itr-1). We demonstrated that the percentage of MP-contaminated nematodes increased with increasing exposure concentrations and duration. The lifespan of nematodes in the lower concentration exposure groups (2.4 × 107 and 2.4 × 108 particles/m2) decreased more prominently than that of higher concentration groups (2.4 × 109 and 2.4 × 1010 particles/m2) after a 72-h exposure period. Concomitantly, expression of the skn-1 gene, involved in detoxification and lifespan regulation, was significantly altered at lower MP concentrations. Physiologically, the defecation rhythm after a 72-h exposure period was most strongly affected by 1 µm MPs at 2.4 × 108 particles/m2. The significant up-regulation of related genes by 1 µm MPs appears responsible for the shortened defecation interval. Results of this study identified a potential toxicity threat to C. elegans from exposure to MPs at environmentally relevant concentrations and provide novel evidence for MP risks to freshwater and terrestrial organisms. Capsule. After exposure to 1 and 5 µm MPs (107-1010 particles/m2), the lifespan of C. elegans decreased more rapidly at lower concentrations.

The rapid detection of microRNA based on p19-enhanced fluorescence polarization.

Via a molecular caliper p19 protein, we have developed an amplified fluorescence polarization method for rapid microRNA detection. This proposed assay has several intrinsic features including rapidity, simplicity, and accuracy.

Adaptive Fuzzy Association Rule mining for effective decision support in biomedical applications.

Due to complexity of biomedical classification problems, it is impossible to build a perfect classifier with 100% prediction accuracy. Hence a more realistic target is to build an effective Decision Support System (DSS). Here 'effective' means that a DSS should not only predict unseen samples accurately, but also work in a human-understandable way. In this paper, we propose a novel adaptive Fuzzy Association Rules (FARs) mining algorithm, named FARM-DS, to build such a DSS for binary classification problems in the biomedical domain. In the training phase, four steps are executed to mine FARs, which are thereafter used to predict unseen samples in the testing phase. The new FARM-DS algorithm is evaluated on two publicly available medical datasets. The experimental results show that FARM-DS is competitive in terms of prediction accuracy. More importantly, the mined FARs provide strong decision support on disease diagnoses due to their easy interpretability.