SRS-Net: a universal framework for solving stimulated Raman scattering in nonlinear fiber-optic systems by physics-informed deep learning.

As a crucial nonlinear phenomenon, stimulated Raman scattering (SRS) plays multifaceted roles involved in forward and inverse problems. In fibre-optic systems, these roles range from detrimental interference that impairs optical performance to beneficial effects that enables various devices such as Raman amplifier. To obtain solutions of SRS, various numerical methods customized for different scenarios have been proposed. However, these methods are time-consuming, low-efficiency, and experience-orientated, particularly in combined scenarios consisting of both forward and inverse problems. Inspired by physics-informed neural networks, we propose SRS-Net, which combines the efficient automatic differentiation and powerful representation ability of neural networks with the regularization of SRS physical laws, to obtain universal solutions for SRS of forward, inverse, and combined problems. We showcase the intuitive solving procedure and high-speed performance of SRS-Net through extensive simulations covering different scenarios. Additionally, we validate its capabilities in experiments involving the high-fidelity modelling of a wavelength division multiplexing system spanning the C + L-band with approximately 10 THz. The versatility of the SRS-Net framework extends beyond SRS, indicating its potential as a promising universal solution in other engineering problems with nonlinear dynamics governed by partial differential equations.

OptiComm-GPT: a GPT-based versatile research assistant for optical fiber communication systems.

With the increasing capacity and complexity of optical fiber communication systems, both academic and industrial requirements for the essential tasks of transmission systems simulation, digital signal processing (DSP) algorithms verification, system performance evaluation, and quality of transmission (QoT) optimization are becoming significantly important. However, due to the intricate and nonlinear nature of optical fiber communication systems, these tasks are generally implemented in a divide-and-conquer manner, which necessitates a profound level of expertise and proficiency in software programming from researchers or engineers. To lower this threshold and facilitate professional research easy-to-start, a GPT-based versatile research assistant named OptiComm-GPT is proposed for optical fiber communication systems, which flexibly and automatically performs system simulation, DSP algorithms verification, performance evaluation, and QoT optimization with only natural language. To enhance OptiComm-GPT's abilities for complex tasks in optical fiber communications and improve the accuracy of generated results, a domain information base containing rich domain knowledge, tools, and data as well as the comprehensive prompt engineering with well-crafted prompt elements, techniques, and examples is established and performs under a LangChain-based framework. The performance of OptiComm-GPT is evaluated in multiple simulation, verification, evaluation, and optimization tasks, and the generated results show that OptiComm-GPT can effectively comprehend the user's intent, accurately extract system parameters from the user's request, and intelligently invoke domain resources to solve these complex tasks simultaneously. Moreover, the statistical results, typical errors, and running time of OptiComm-GPT are also investigated to illustrate its practical reliability, potential limitations, and further improvements.

Double-blinded, randomized clinical trial of Gegen Qinlian decoction pinpoints Faecalibacterium as key gut bacteria in alleviating hyperglycemia.

Background: Accumulating evidence suggests that metabolic disorders, including type 2 diabetes mellitus (T2DM), can be treated with traditional Chinese medicine formulas, such as the Gegen Qinlian decoction (GQD). This study elucidates the mechanisms by which gut microbes mediate the anti-diabetic effects of GQD. Methods: We conducted a double-blind randomized clinical trial involving 120 untreated participants with T2DM. During the 12-week intervention, anthropometric measurements and diabetic traits were recorded every 4 weeks. Fecal microbiota and serum metabolites were measured before and after the intervention using 16S rDNA sequencing, liquid chromatography-mass spectrometry, and Bio-Plex panels. Results: Anti-diabetic effects were observed in the GQD group in the human trial. Specifically, glycated hemoglobin, fasting plasma glucose, and two-hour postprandial blood glucose levels were significantly lower in the GQD group than in the placebo group. Additionally, Faecalibacterium was significantly enriched in the GQD group, and the short-chain fatty acid levels were higher and the serum inflammation-associated marker levels were lower in the GQD group compared to the placebo group. Moreover, Faecalibacterium abundance negatively correlated with the levels of serum hemoglobin, fasting plasma glucose, and pro-inflammatory cytokines. Finally, the diabetes-alleviating effect of Faecalibacterium was confirmed by oral administration of Faecalibacterium prausnitzii (DSMZ 17677) in T2DM mouse model. Conclusions: GQD improved type 2 diabetes primarily by modulating the abundance of Faecalibacterium in the gut microbiota, alleviating metabolic disorders and the inflammatory state. Trial registration: Registry No. ChiCTR-IOR-15006626.

Identifying and charactering a 4-aminobutyryl-CoA ligase for the production of butyrolactam.

Butyrolactam, a crucial four-carbon molecule, serves as building block in synthesis of polyamides. While biosynthesis of butyrolactam from renewable carbon sources offers a more sustainable approach, it has faced challenges in achieving high product titer and yield. Here, an efficient microbial platform for butyrolactam production was constructed by elimination of rate-limiting step and systematic pathway optimization. Initially, a superior 4-aminobutyryl-CoA ligase was discovered and characterized among six acyl-CoA ligases from different sources, which greatly improved the pathway efficiency. Subsequent optimizations were implemented to further enhance butyrolactam production, including promoter engineering, the elimination of competing pathways, transporter engineering and improving the availability of precursors. There efforts resulted in achieving approximately 2 g/L butyrolactam in shake flask experiments. Finally, the biosynthesis of butyrolactam was scaled up in a 3-L bioreactor in 84 hours, resulting in a significantly increased production of 45.2 g/L, with a carbon yield of 0.34 g/g glucose. This study highlights the construction of a microbial platform with the capability to achieve elevated levels of butyrolactam production and unlocks its potential in sustainable manufacturing processes.

Metagenome-wide analysis uncovers gut microbial signatures and implicates taxon-specific functions in end-stage renal disease.

BACKGROUND: The gut microbiota plays a crucial role in regulating host metabolism and producing uremic toxins in patients with end-stage renal disease (ESRD). Our objective is to advance toward a holistic understanding of the gut ecosystem and its functional capacity in such patients, which is still lacking. RESULTS: Herein, we explore the gut microbiome of 378 hemodialytic ESRD patients and 290 healthy volunteers from two independent cohorts via deep metagenomic sequencing and metagenome-assembled-genome-based characterization of their feces. Our findings reveal fundamental alterations in the ESRD microbiome, characterized by a panel of 348 differentially abundant species, including ESRD-elevated representatives of Blautia spp., Dorea spp., and Eggerthellaceae, and ESRD-depleted Prevotella and Roseburia species. Through functional annotation of the ESRD-associated species, we uncover various taxon-specific functions linked to the disease, such as antimicrobial resistance, aromatic compound degradation, and biosynthesis of small bioactive molecules. Additionally, we show that the gut microbial composition can be utilized to predict serum uremic toxin concentrations, and based on this, we identify the key toxin-contributing species. Furthermore, our investigation extended to 47 additional non-dialyzed chronic kidney disease (CKD) patients, revealing a significant correlation between the abundance of ESRD-associated microbial signatures and CKD progression. CONCLUSION: This study delineates the taxonomic and functional landscapes and biomarkers of the ESRD microbiome. Understanding the role of gut microbiota in ESRD could open new avenues for therapeutic interventions and personalized treatment approaches in patients with this condition.

Instantaneous Free Radical Scavenging by CeO2 Nanoparticles Adjacent to the Fe-N4 Active Sites for Durable Fuel Cells.

To achieve the Fe-N-C materials with both high activity and durability in proton exchange membrane fuel cells, the attack of free radicals on Fe-N4 sites must be overcome. Herein, we report a strategy to effectively eliminate radicals at the source to mitigate the degradation by anchoring CeO2 nanoparticles as radicals scavengers adjacent (Scaad-CeO2 ) to the Fe-N4 sites. Radicals such as ⋅OH and HO2 ⋅ that form at Fe-N4 sites can be instantaneously eliminated by adjacent CeO2 , which shortens the survival time of radicals and the regional space of their damage. As a result, the CeO2 scavengers in Fe-NC/Scaad-CeO2 achieved ∼80 % elimination of the radicals generated at the Fe-N4 sites. A fuel cell prepared with the Fe-NC/Scaad-CeO2 showed a smaller peak power density decay after 30,000 cycles determined with US DOE PGM-relevant AST, increasing the decay of Fe-NCPhen from 69 % to 28 % decay.

Honeycomb layered topology construction for exceptional long-wave infrared nonlinear optical crystals.

Nonlinear optical (NLO) crystals capable of efficient long-wave infrared (8-14 µm) laser output remain scarce, and the exploration of long-wave IR NLO materials with superior comprehensive optical performances is a momentous challenge. Herein, we develop two selenide-halide NLO crystals, Hg3AsSe4Br and Hg3AsSe4I, which are derived from the honeycomb layered topology of prototype GaSe. Remarkably, they exhibit not only strong SHG effects, suitable band gap, large birefringence, broad IR transparency range and low two-photon absorption coefficients but reinforced interlayer interaction and more benign crystal growth habit, compared to those of GaSe, indicating that they are promising long-wave IR NLO materials. Moreover, Hg3AsSe4I achieved better comprehensive optical properties than conventional IR crystals, GaSe, ZnGeP2, CdSe and AgGaSe2. The idea of honeycomb layered topology construction provides a material design heuristic to explore cutting-edge IR NLO materials.

Cryptotanshinone inhibits oral squamous cell carcinoma through the autophagic pathway.

Oral squamous cell carcinoma (OSCC) is one of the most common malignant tumors with a low quality of life. Because traditional surgical treatment often causes large wounds and then affects the quality of life of patients, it is urgent to find new and efficient drugs with good safety for clinical treatment. This study aimed to identify potential anticancer drugs starting from the traditional Chinese medicine Salvia miltiorrhiza extract. Cryptotanshinone, a compound isolated from the Chinese herb Salvia miltiorrhiza, was found to significantly induce apoptosis and inhibit proliferation in OSCC. By electron microscopy, autophagosomes were found. Confocal fluorescence microscopy data showed that cryptotanshinone significantly induced autophagy in OSCC cells. Mechanistically, the western blot assay indicated that cryptotanshinone induced cell autophagy through the activation of the LC3 pathway, whereas the autophagy inhibitor 3-methyladenine attenuated these effects. Furthermore, we demonstrated that cryptotanshinone had a significant antitumor effect in a tumor xenograft model, and no damage to vital organs was observed. Our findings provide evidence that cryptotanshinone may be a novel therapeutic strategy for the treatment of OSCC.

Uncovering a Vital Band Gap Mechanism of Pnictides.

Pnictides are superior infrared (IR) nonlinear optical (NLO) material candidates, but the exploration of NLO pnictides is still tardy due to lack of rational material design strategies. An in-depth understanding structure-performance relationship is urgent for designing novel and eminent pnictide NLO materials. Herein, this work unravels a vital band gap mechanism of pnictides, namely P atom with low coordination numbers (2 CN) will cause the decrease of band gap due to the delocalization of non-bonding electron pairs. Accordingly, a general design paradigm for NLO pnictides, ionicity-covalency-metallicity regulation is proposed for designing wide-band gap NLO pnictides with maintained SHG effect. Driven by this idea, millimeter-level crystals of MgSiP2 are synthesized with a wide band gap (2.34 eV), a strong NLO performance (3.5 x AgGaS2 ), and a wide IR transparency range (0.53-10.3 µm). This work provides an essential guidance for the future design and synthesis of NLO pnictides, and also opens a new perspective at Zintl chemistry important for other material fields.

Mg2In3Si2P7: A Quaternary Diamond-like Phosphide Infrared Nonlinear Optical Material Derived from ZnGeP2.

Balancing the second-harmonic generation (SHG) coefficient, band gap, and birefringence is a vital but addressable challenge for designing infrared nonlinear optical materials. By applying a "rigidity-flexibility coupling" strategy, a quaternary diamond-like phosphide, Mg2In3Si2P7, with wurtzite-type superstructure was successfully designed and synthesized. Remarkably, it achieved the rare coexistence of giant second-harmonic generation (2 × ZnGeP2 and 7.1 × AgGaS2), suitable band gap (2.21 eV), moderate birefringence (0.107), and wide IR transparent range (0.56-16.4 µm). First-principles calculations revealed that the giant SHG response and large birefringence can be attributed to the synergy of arrangement-aligned [InP4] and [SiP4] tetrahedra. This work not only opens a new avenue for designing advanced infrared nonlinear optical materials but also may spur more explorations on quaternary diamond-like pnictides.

Molecular, Cellular and Functional Changes in the Retinas of Young Adult Mice Lacking the Voltage-Gated K+ Channel Subunits Kv8.2 and K2.1.

Cone Dystrophy with Supernormal Rod Response (CDSRR) is a rare autosomal recessive disorder leading to severe visual impairment in humans, but little is known about its unique pathophysiology. We have previously shown that CDSRR is caused by mutations in the KCNV2 (Potassium Voltage-Gated Channel Modifier Subfamily V Member 2) gene encoding the Kv8.2 subunit, a modulatory subunit of voltage-gated potassium (Kv) channels. In a recent study, we validated a novel mouse model of Kv8.2 deficiency at a late stage of the disease and showed that it replicates the human electroretinogram (ERG) phenotype. In this current study, we focused our investigation on young adult retinas to look for early markers of disease and evaluate their effect on retinal morphology, electrophysiology and immune response in both the Kv8.2 knockout (KO) mouse and in the Kv2.1 KO mouse, the obligate partner of Kv8.2 in functional retinal Kv channels. By evaluating the severity of retinal dystrophy in these KO models, we demonstrated that retinas of Kv KO mice have significantly higher apoptotic cells, a thinner outer nuclear cell layer and increased activated microglia cells in the subretinal space. Our results indicate that in the murine retina, the loss of Kv8.2 subunits contributes to early cellular and physiological changes leading to retinal dysfunction. These results could have potential implications in the early management of CDSRR despite its relatively nonprogressive nature in humans.

miR-139-5p mediates the palmitate-induced inhibition of insulin secretion by targeting neuronal pentraxin 1 in INS-1 cells.

High fatty acid reduces insulin secretion in pancreatic ß-cells and miR-139-5p is increased in diabetic pancreatic tissues and induces islet ß-cell apoptosis. However, to date, there is no study exploring whether or not miR-139-5p is involved in high fatty acid-induced insulin secretion. In the present study, INS-1 cells were exposed to different concentrations (0.1, 0.2, and 0.4 mM) of palmitate for different time periods (12, 24, and 48 h). The expression levels of miR-139-5p and neuronal pentraxin 1 (NPTX1) were evaluated by real-time PCR and western blot analysis. The regulation of NPTX1 by miR-139-5p was examined by luciferase assay. Cell transfection was conducted using Lipo8000 or Lipofectamine RNAiMAX. Potassium or glucose-stimulated insulin secretion levels were used to verify the function of miR-139-5p or NPTX1 in insulin secretion. Insulin secretion levels were detected by radioimmunoassay. We found that miR-139-5p was increased in INS-1 cells stimulated with palmitate. In addition, miR-139-5p was also elevated in islets of high-fat diet-fed mice and db/db mice compared to those in islets of normal diet-fed mice and wild-type mice. Knockdown of miR-139-5p could reverse high fatty acid-induced insulin secretion defects in INS-1 cells. Furthermore, we demonstrated that NPTX1 is a target of miR-139-5p. miR-139-5p mediated palmitate-induced insulin secretion defects by targeting NPTX1. Moreover, palmitate treatment declined the expression of NPTX1 and the NPTX1 expression was also decreased in islets of high-fat diet-fed mice and db/db mice. Impaired NPTX1 expression is involved in fatty acid-induced insulin secretion defects. Collectively, our results illustrate that the induction of ß-cell insulin secretion defects by fatty acids is mediated, at least in part, by miR-139-5p via downregulation of NPTX1 expression.

Neutrophil to Lymphocyte Ratio as a Predictor of Long-Term Outcome in Peritoneal Dialysis Patients: A 5-Year Cohort Study.

INTRODUCTION: The mortality of peritoneal dialysis (PD) patients remains high. The neutrophil to lymphocyte ratio (NLR), as an indicator of systemic inflammation, has been considered to be a predictor of cardiovascular and all-cause mortality in hemodialysis patients. The present study aims to investigate the relationship between NLR and long-term outcome in PD patients. MATERIALS AND METHODS: The study included patients who initiated PD for at least 3 months between January 1, 2013, and December 31, 2015. All the patients were followed up until death, cessation of PD, or to the end of the study (June 31, 2018). NLR was calculated as the ratio of neutrophils to lymphocytes. RESULTS: A total of 140 patients were included in this study. The median NLR reported was 2.87. Patients with lower NLR showed a higher survival rate than patients with higher NLR (log rank 6.886, p = 0.009). Furthermore, patients with higher NLR had a significantly higher cardiovascular mortality (log rank 5.221, p = 0.022). Multivariate Cox proportional hazards model showed that older age (HR 1.054, 95% CI 1.017-1.092, p = 0.004), higher Ca × P (HR 1.689, 95% CI 1.131-2.523, p = 0.010), and higher NLR (HR 2.603, 95% CI 1.037-6.535, p = 0.042) were independent predictors of increased all-cause mortality. NLR was also independently associated with cardiovascular mortality (HR 2.886, 95% CI 1.005-8.283, p = 0.039). Higher NLR (HR 2.667, 95% CI 1.333-5.337, p = 0.006), older age (HR 1.028, 95% CI 1.005-1.052, p = 0.016), and history of cardiovascular disease (HR 1.426, 95% CI 1.195-3.927, p = 0.031) were significantly independently associated with poor peritonitis-free survival in this study. CONCLUSIONS: NLR could be a strong predictor of long-term outcome in PD patients.

Porous hydrogen-bonded organic framework membranes for high-performance molecular separation.

Hydrogen-bonded organic frameworks (HOFs) with intrinsic, tunable, and uniform pores are promising candidates to act as membranes for molecular separation, but they are yet to be explored in this field. Herein, a type of HOF membrane based on a thin-film nanocomposite (TFN) membrane containing porous HOF (PFC-1) nanoparticles was successfully fabricated via a facile interfacial polymerization method. The homogeneously distributed HOF nanoparticles can provide direct channels in the polyamide (PA) active layer for molecule separation. Due to the ultrathin nature of the TFN membrane and the highly ordered porous structure of the PFC-1 nanoparticles, these flexible HOF membranes exhibit both ultrahigh water permeability (∼546.09 L m-2 h-1 bar-1) and the excellent rejection of dye molecules (e.g., rhodamine B rejection of >97.0%). Furthermore, long-term operational stability (>50 min) and satisfactory cycling performance (>5 cycles) have also been achieved. This study may shed light on the fabrication of HOF membranes for liquid-phase molecular separation.

Indoxyl sulfate and high-density lipoprotein cholesterol in early stages of chronic kidney disease.

BACKGROUND: High IS level has been demonstrated to be associated with vascular calcification and lymphocyte functional disorders, which are both risk factors of CVD. Low HDL-c level is a risk factor of CVD in CKD patients. This study was designed to explore the potential relationship between IS and HDL-c levels in early stages of CKD population. METHODS: Patients of CKD stage 1-3 were enrolled in this cross-sectional study. Correlations between HDL-c and IS levels were investigated among various clinicopathological variables through independent samples t test and multivariate logistic regression. RESULTS: A total of 205 CKD patients (96 men) aged 43.27 ± 13.80 years old were included in this research. There were 96 patients (46 men) in CKD stage1 and 109 (50 men) in CKD stage 2 or stage 3. IS levels were significantly higher in CKD 2 + 3 group (1.50 ± 1.74 µg/ml vs. 0.94 ± 0.66 µg/ml, p = 0.007), while HDL-c levels were lower (1.19 ± 0.39 mmol/L vs. 1.33 ± 0.45 mmol/L, p = 0.017) compared to CKD 1 group. Among all the patients, a negative correlation was observed between IS and HDL-c levels (r = -0.244, p = 0.001). IS level was an independent risk factor for low HDL-c (<1.04 mmol/L) incidence even after controlling for potential confounders including concomitant disease, age, sex, blood pressure, BMI and laboratory biochemical test including eGFR (OR = 1.63, 95% CI: 1.11-2.39, p = 0.013). IS and HDL-c were both risk factors for predicting CKD stage 3. CONCLUSIONS: In early CKD stages, low HDL-c level is associated with increased IS levels, which may be an important contributor in the development of dyslipidemia in CKD patients.

A Novel Antidiabetic Monomers Combination Alleviates Insulin Resistance Through Bacteria-Cometabolism-Inflammation Responses.

The present study sought to examine the therapeutic effect of a novel antidiabetic monomer combination (AMC) in treating type 2 diabetes mellitus (T2DM); while also elucidating the potential functional mechanism. Male C57BL/6J mice were fed a high-fat diet (HFD) for 12 weeks to establish T2DM. The AMC group showed significant reduction in weight, fasting blood glucose (FBG), serum total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C), and experienced reduced insulin resistance based on oral glucose tolerance testing (OGTT) and hyperinsulinemic-euglycemic clamp testing ("gold standard" for determining in vivo insulin sensitivity). Further, AMC restored the altered intestinal flora by increasing the abundance of the beneficial bacteria Akkermansia, and decreasing the number of harmful bacteria, including Bacteroides, Odoribacter, Prevotella 9, Alistipes, and Parabacteroides. Components of the host-microbial metabolome were also significantly changed in the AMC group compared to the HFD group, including hydroxyphenyllactic acid, palmitoleic acid, dodecanoic acid, linoleic acid, and erucic acid. Furthermore, AMC was found to inhibit inflammation and suppress signaling pathways related to insulin resistance. Lastly, spearman correlation analysis revealed relationships between altered microbial community and co-metabolite levels, co-metabolites and inflammatory cytokines. Hence, the potential mechanism responsible for AMC-mediated alleviation of insulin resistance was suggested to be involved in modulation of bacteria-cometabolism-inflammation responses.

Serum Triglycerides Are Related to Chronic Kidney Disease (CKD) Stage 2 in Young and Middle-Aged Chinese Individuals During Routine Health Examination.

BACKGROUND The aim of this study was to determine the risk factors for early chronic kidney disease (CKD) (GFR 60-89 ml/min/1.73 m²; CKD stage 2) in asymptomatic Chinese individuals undergoing routine health examination. MATERIAL AND METHODS This cross-sectional study enrolled 9100 individuals who received voluntary medical examinations between 10/01/2011 and 09/30/2017. Demographic data, clinical history, clinical examination, medication, smoking, alcohol, blood biochemistry, urinalysis, and carotid ultrasound were extracted from the medical records. All laboratory analyses were performed routinely. Multivariable logistic regression for factors predicting CKD stage 2 was performed. RESULTS A total of 9100 individuals were enrolled (age of 18-65 and 65.4% male). CKD stage 2 was found in 1989/9100 individuals (21.9%). Male gender (OR=6.711, 95%CI: 5.376-8.403, P<0.001), older age (OR=1.077, 95%CI: 1.068-1.086, P<0.001), hemoglobin levels (OR=1.051, 95%CI: 1.046-1.057, P<0.001), triglycerides levels (OR=1.174, 95%CI: 1.067-1.292, P=0.001), HDL-C (OR=0.539, 95%CI: 0.380-0.763, P<0.001), Lp(a) levels (OR=1.000, 95%CI: 1.000-1.001, P=0.03), and carotid atherosclerosis (OR=1.248, 95%CI: 1.005-1.550, P=0.045) were associated with CKD stage 2 among all subjects. Serum triglycerides levels were associated with CKD stage 2 in the 18-45 and 45-65 years of age subgroups. CONCLUSIONS Factors that are routinely assessed during routine health examinations (male gender, age, hemoglobin levels, triglycerides levels, HDL-C, Lp(a) levels, and carotid atherosclerosis) can help identify individuals at higher risk of having CKD stage 2. The Chinese dyslipidemia is characterized by high triglycerides and low HDL-C and occurs in young and middle-aged individuals. Those factors could help identify individuals at higher risk for CKD stage 2 and who could benefit from preventive treatments.