Search Results (557)

Accurate satellite retrieval of oceanic particulate organic nitrogen (PON) vertical profile is essential for understanding global biogeochemical processes; however, no dedicated retrieval models currently exist. This study developed a novel PON profile retrieval model using the eXtreme Gradient Boosting (XGBoost) algorithm, based on a comprehensive global dataset that includes in situ PON measurements, MODIS-Aqua bio-optical data, and 3D reanalysis physical data. The XGBoost-retrieved PON profiles were compared with those derived from Copernicus particulate backscattering coefficient ($b_{\mathit{bp}}$) profiles and were further used to estimate the euphotic-zone PON stocks through an optimally performing regression model. The results showed that the proposed model significantly outperformed models constructed without physical inputs, achieving $R^2$ of 0.83, RMSE of 1.49 $\mathrm{mg} {\mathrm{m}}^{-3}$ and MAPE of 18.07%. Compared to the $b_{\mathit{bp}}$-based profiles, the XGBoost-retrieved profiles exhibited higher accuracy. The model also provided reliable estimates of euphotic-zone PON stocks, with $R^2$ of 0.76, RMSE of 200.31 mg ${\mathrm{m}}^{-2}$ and MAPE of 15.09%. These findings demonstrate the potential of the proposed retrieval model for investigating oceanic nitrogen dynamics and biogeochemical cycles. Full article

The advent of sixth-generation (6G) communications envisions a paradigm of ubiquitous intelligence and seamless physical–digital fusion, demanding unprecedented performance from the optical transport infrastructure. Achieving terabit-per-second capacities, microsecond latency, and nanosecond synchronisation precision requires a convergent, flexible, open, and AI-native x-Haul architecture that integrates communication with distributed edge computing. This study conducts a systematic literature review of recent advances, challenges, and enabling optical technologies for intelligent and autonomous 6G networks. Using the PRISMA methodology, it analyses sources from IEEE, ACM, and major international conferences, complemented by standards from ITU-T, 3GPP, and O-RAN. The review examines key optical domains including Coherent PON (CPON), Spatial Division Multiplexing (SDM), Hollow-Core Fibre (HCF), Free-Space Optics (FSO), Photonic Integrated Circuits (PICs), and reconfigurable optical switching, together with intelligent management driven by SDN, NFV, and Artificial Intelligence/Machine Learning (AI/ML). The findings reveal that achieving 6G transport targets will require synergistic integration of multiple optical technologies, AI-based orchestration, and nanosecond-level synchronisation through Precision Time Protocol (PTP) over fibre. However, challenges persist regarding scalability, cost, energy efficiency, and global standardisation. Overcoming these barriers will demand strategic R&D investment, open and programmable architectures, early AI-native integration, and sustainability-oriented network design to make optical fibre a key enabler of the intelligent and autonomous 6G ecosystem. Full article

This study evaluates the performance of a hybrid passive optical network–radio over fiber (PON–RoF) architecture for long-term evolution (LTE)-based video transmission, focusing on the analysis of the block error rate (BLER) with and without an external RF amplifier. The results show that removing it improves receiver sensitivity by 4.04 dB in the optical link and 16 dB in the hybrid RoF link. The internal gain control of the USRP-2944R (Universal Software Radio Peripheral) is sufficient for signal processing without saturating the receiver. Furthermore, the received power levels are consistent with typical GPON sensitivity and overload ranges reported in standards, although the experimental setup corresponds to a continuous point-to-point laboratory link rather than a full GPON burst-mode configuration. Full article

Cuban sugarcane wax alcohol (policosanol) is a blend of eight characteristic aliphatic alcohols extracted from the Cuban sugarcane and widely recognized for its multifunctional applications and therapeutic properties. In the present study, the potency of policosanol (POL) was assessed for its ability to prevent metabolic stress and associated disorders posed by a high-cholesterol (HC) and high-galactose (HG) diet in zebrafish (Danio rerio). Adult zebrafish (n = 56/group) were fed either with an HC+HG diet (containing 4%, w/w cholesterol and 30%, w/w galactose), or an HC+HG amalgamated diet with POL (final 0.1% w/w or 0.5% w/w). Zebrafish in the specified groups were sacrificed post-30 weeks of feeding, and blood and organs (liver, brain, and eyes) were processed for biochemical, histological, and immunohistochemical (IHC) analysis. After 30 weeks of feeding, the highest mortality (12.5%) was noticed in the HC+HG supplement group, which was reduced to 4.5% with co-supplementation of POL (0.1% and 0.5%). In a dose-dependent manner, POL significantly reversed HC+HG elevated levels of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), glucose, and malondialdehyde (MDA), while substantially augmenting plasma high-density lipoprotein cholesterol (HDL-C), sulfhydryl content, ferric ion reduction ability (FRA), and paraoxonase (PON) activity. In addition, POL mitigated HC+HG-induced hepatomegaly, inflammation, and fatty liver changes. Consistently, POL minimizes ROS generation and cellular senescence in the brain and substantially improves HC+HG-induced cognitive changes (cessation of swimming ability and motion), with a marked ~5 times higher swimming distance. Notably, POL mitigated the HC+HG-induced corneal opacity and attenuated oxidative stress, apoptosis, 4-hydroxynonenal (4-HNE) accumulation, and myelin sheath degeneration in the retina. The findings underscore the therapeutic potential of policosanol in attenuating oxidative stress, metabolic changes, and various organ damage caused by prolonged exposure to the HC+HG diet. Full article

For the first time, a highly energy-efficient 32-parallel 64-point FFT scheme for IMDD OFDM-PON is proposed and implemented on a Xilinx ML605 platform. By experimentally verifying the power consumption model for the FPGA logic resources utilized in the FFT, the relationship between FFT calculating consumption and FPGA logic resource usage is established. Based on this relationship, we derive a resource selection principle for the FFT bit resolution optimization to minimize power consumption under different levels of received optical power. Consequently, the proposed FFT achieves a 76.1% reduction in power consumption compared to the traditional Spiral FFT at a received optical power of −21 dBm. Based on the proposed FFT, the real-time OFDM-PON receiver power consumption can save up to 43% compared with traditional OFDM-PON system. Full article

Background/Objectives: Ponatinib (PON) is a potent anticancer drug widely used to treat chronic myeloid leukemia (CML). Although many cancer survivors benefit from such therapies, managing drug-induced side effects, especially cardiotoxicity, remains a major challenge. Despite its prevalence, the exact mechanisms underlying PON-induced cardiotoxicity have not been thoroughly investigated. Additionally, the potential of Bone Morphogenetic Protein 7 (BMP-7) to alleviate these cardiotoxic effects has yet to be explored. Methods: To address these essential questions, we conducted a study using C57BL/6 mice. Mice were treated with PON (25 mg/kg cumulative dosage) or a combination of PON and BMP-7 (600 μg/kg), alongside a suitable control group. Heart function was assessed by echocardiography. Different techniques were performed to evaluate the apoptotic pathway. Histological staining was performed to investigate structural changes. Results: PON treatment increased apoptotic cell death (increased expression of BAX and caspase-3) in the heart through the PTEN/Akt signaling pathway. Further, PON treatment led to increased cardiac hypertrophy, adverse remodeling, and reduced cardiac function. Importantly, BMP-7 markedly reduced PON-induced apoptosis (increased Bcl2 expression) and its downstream effects. Conclusions: These results suggest that BMP-7 might inhibit PON-induced cardiotoxicity. Furthermore, our findings pave the way for future translational studies with BMP-7, which can demonstrate the therapeutic potential of BMP-7 in a clinical setting. Full article

Background and Objectives: Multiple myeloma (MM) remains an incurable plasma cell malignancy with heterogeneous clinical outcomes. Although current prognostic systems integrate biochemical and cytogenetic parameters, they do not fully capture disease complexity. Adipocytes within the bone marrow microenvironment secrete adipokines that regulate inflammation, metabolism, and immune interactions and may influence disease progression. This study aimed to assess circulating adipokines and related microenvironmental mediators as potential biomarkers of disease activity and treatment response in MM. Materials and Methods: In this case–control, cross-sectional study, the serum levels of eight adipokine-related molecules—adiponectin, leptin, resistin, chemerin, adipsin, thrombospondin-1 (TSP-1), paraoxonase-1 (PON-1), and myeloperoxidase (MPO)—were measured in 40 MM patients and 38 age- and sex-matched healthy controls. Enzyme-linked immunosorbent assays (ELISA) and bead-based multiplex immunoassays were used. Associations with prognostic markers (serum β₂-microglobulin (sB2M), LDH, albumin, hemoglobin, renal function) and treatment response were analyzed using correlation and non-parametric statistical methods. Results: Compared to the controls, MM patients exhibited significantly higher circulating levels of adiponectin, resistin, chemerin, adipsin, TSP-1, and MPO, while leptin was decreased. Among clinical correlations, chemerin and PON-1 correlated positively with sB2M, TSP-1 correlated with LDH, and MPO correlated with M-protein and albumin. Resistin was lower in patients with renal impairment and an advanced disease stage. Adiponectin and TSP-1 were significantly lower in progressive disease compared to complete remission, suggesting their potential association with treatment response. Conclusions: This study demonstrates that multiple adipokines are dysregulated in MM and exhibit distinct associations with disease burden, renal function, and therapeutic response. Novel associations identified for TSP-1, PON-1, and adipsin highlight previously unrecognized microenvironmental pathways in MM biology. Adipokine profiling may complement established prognostic markers and provide new insights into the tumour microenvironment in MM. Full article

The Paraoxonase (PON) gene family consists of three paralogues (PON1, PON2 and PON3) that are tandemly located on chromosome 7. In this review paper, the structure and function of the encoded proteins is summarized. In addition, an overview is given on the generated animal models. Finally, their involvement in the pathogenesis of different diseases is discussed, starting from an extended screening of the literature using PUBMED and Web of Science. PON1 and PON3 are mainly expressed in the liver and released into the bloodstream, bound to high-density lipoprotein. PON2 is expressed in various tissues, including the liver, lungs, heart, placenta and testes, but remains intracellular. The name of the enzyme family reflects PON1′s ability to neutralize paraoxon, but they also exhibit lactonase and esterase activities. All three PON enzymes play a role in reducing lipid peroxides in High-Density Lipoproteïne (HDL) and low-density lipoprotein(LDL), giving them antioxidant properties. This links them to Metabolic dysfunction-Associated Steatotic Liver Disease (MASLD), a metabolic liver condition marked by the excessive accumulation of triglycerides (TG) in liver cells. In addition to their association with MASLD, the PON genes are, due to their antioxidant properties, also associated with other conditions including cardiovascular diseases, chronic kidney disease, neurological and immunological conditions up to some forms of cancer. In the latter, the antioxidant properties can result in tumor progression by protecting malignant cells from oxidative damage thus supporting survival, proliferation and metastasis indicating them as potential drug targets for treatment of cancer. Therefore, further research on this protein family can provide novel insights into their function and their potential therapeutic applicability. Full article

Wavelength Division Multiplexing-based Passive Optical Networks (WDM-PONs) are among the most advanced optical networks without active elements, using a wide range of wavelengths to increase network reliability, scalability, and capacity. This ensures the provision of high quality, fast, and available services for end users. In this aim, traffic protection considerations have markedly enhanced their role. Traffic protection schemes can be divided into Point-To-MultiPoint (P2MP) and ring architectures. Traffic protection scenarios of access WDM-PONs in the P2MP architecture include Type B, dual-parented Type B, and Type C, while the ring architecture includes protected access and metropolitan-access WDM-PONs. Any potential traffic protection scheme can be represented by a corresponding reliability block diagram for the purpose of cost–benefit analysis. An important aspect of the WDM-PON design is presented by the Capital (CAPEXs) and Operational (OPEXs) Expenditures, which play a key role in network optimization. Managing them efficiently allows us to achieve an economically sustainable and efficient infrastructure of future passive optical networks involving traffic protection schemes. In this work, we focused on simulation model development for calculating the CAPEX and OPEX costs and the subsequent cost–benefit analysis of possible WDM-PON traffic protection schemes. Full article

Serum activity of paraoxonase-1 (PON-1) decreases in canine inflammation. This study aimed to evaluate how frequently PON-1 activity is reduced across different disease categories and to assess its potential prognostic significance. PON-1 activity was measured in 482 samples (435 first visit, 47 follow-up) collected during routine clinical activities. The emergency/first-opinion unit (EF) had the highest frequency of low values (18.3%) and lower median PON-1 activity (170.3 U/mL) compared with other units. The proportion of lower values and median PON-1 values were, respectively, significantly higher and lower in acute/severe diseases compared with chronic/mild diseases (13.3 vs. 7.1%; 177.0 vs. 192.9 U/mL) and in hospitalized compared with non-hospitalized dogs (27.7 vs. 4.5%; 150.0 vs. 193.0 U/mL). Low PON-1 activity may predict the need for hospitalization: values < 45.7 U/mL have a likelihood ratio of 14.4. The proportion of lower values and the median Paraoxonase-1 activity did not differ between survivors and non-survivors (18.2 vs. 25.0%; 162.0 vs. 161.3 U/mL). However, PON-1 activity diminished during hospitalization only in non-survivors. PON-1 activity should be measured in routine practice, especially in the EF; hospitalization may be warranted when results are markedly low. Decreases in PON-1 activity during hospitalization may suggest a negative outcome. Full article

Insulin resistance (IR) contributes to atherogenic dyslipidemia and elevated ASCVD risk. Apolipoprotein A1 (ApoA1)-associated lipoproteins have diverse anti-atherogenic functions, but it is unclear whether IR drives adverse changes in their proteomic composition. We hypothesized that IR is associated with an atherogenic ApoA1 proteome and that insulin-sensitizing interventions would improve its composition. We studied 861 participants without diabetes (age 47 ± 12 years, 65.5% female). IR was directly measured using the steady-state plasma glucose (SSPG) concentration via the insulin suppression test. ApoA1-associated proteins were quantified by mass spectrometry. A subset underwent interventions for 3 months (N total 108): pioglitazone, PIO n = 38 or weight loss, WL n = 70). Paired t-tests assessed pre- and post-intervention changes. At baseline, several ApoA1-associated proteins significantly correlated with SSPG. Both interventions improved IR (p < 0.01). PIO led to significant increases in 14 ApoA1-associated proteins, including ApoC1–C4, ApoA2, ApoA4, ApoD, ApoE, LCAT, and PON1/3. WL increased several ApoA1-associated proteins, including ApoA4, ApoD, ApoM, and PON1/3. In conclusion, IR is associated with a pro-atherogenic ApoA1 proteome, and both interventions improve this profile. However, PIO has a broader proteomic impact. These findings highlight the potential of targeting the ApoA1 proteome to reduce residual ASCVD risk. Full article

Oxidative stress-induced mitochondrial dysfunction has been identified as a central driver of cellular senescence and age-related degeneration. The present study investigated the potential of vutiglabridin, a paraoxonase 2 (PON2) agonist, to mitigate reactive oxygen species (ROS)-induced senescence in human LO2 hepatocytes. The process of senescence was induced by the administration of hydrogen peroxide, followed by the recovery of the cells in fresh medium. The levels of intracellular ROS, the senescence-associated β-galactosidase staining, the p16/p21 expression, and the mitochondrial morphology were the focus of a comprehensive assessment utilizing a range of analytical techniques, including microscopy, quantitative PCR, and Western blotting. The present study demonstrated that the administration of vutiglabridin resulted in a dose-dependent reduction in attenuation of the expression of senescence markers. Transmission electron microscopy (TEM) and stimulated emission depletion (STED) imaging revealed the preservation of mitochondrial structure and network connectivity in cells treated with vutiglabridin. These effects were absent in PON2 knockout cells, confirming that vutiglabridin’s action requires functional PON2. The present study demonstrates that vutiglabridin alleviates oxidative stress-induced cellular senescence by preserving mitochondrial integrity and redox balance via a PON2-dependent mechanism. This study lends further support to the investigation of the PON2 pathway as a therapeutic target in age-related cellular dysfunction. Full article

Despite a specific histone mutation defining the unique genetic makeup, diffuse midline gliomas are heterogeneous tumors with a wide range of morphologic and molecular spectrum. We investigated the feasibility of using hyperpolarized carbon-13(¹³C) MR metabolic imaging to differentiate distinctive molecular features from two H3K27M-mutant, biopsy-originated diffuse midline glioma xenografts. ¹³C MR metabolic imaging data were acquired on a 3T scanner from 12 rats that had been implanted with SF8628 or SF7761 diffuse midline glioma cells in brainstem, following injection of hyperpolarized [1-¹³C]pyruvate. Despite the two tumors’ similar appearance of T₂-hyperintensity throughout the cerebellum and pons without contrast enhancement, ¹³C metabolic imaging data revealed that SF8627 had significantly higher ratios of lactate to pyruvate, lactate to total carbon, and normalized lactate than SF7761. Elevated lactate levels in SF8628 were associated with large amounts of lactate dehydrogenase (LDH)-A and carbonic anhydrase-IX staining in SF8628 compared to SF7761, which implied that the highly hypoxic condition in SF8628 appeared to contribute to the high level of LDH-A enzyme activity, which, in turn, induced the large conversion from hyperpolarized pyruvate to lactate. Our findings suggest that this advanced metabolic imaging technique may be used for the noninvasive characterization of molecular hypoxia and lactate dehydrogenase-A activity in these pediatric brainstem gliomas. Full article

Background/Objectives: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive loss of motor function, which affects mobility and leads to secondary complications, including altered dietary intake due to dysphagia, fatigue, and hypermetabolism, particularly affecting vitamin consumption, which are essential micronutrients for neuromuscular performance. The specific relationship between vitamin intake and muscle activation is not well understood in patients with ALS; thus, it is relevant to identify blood biomarkers that reflect muscle status. Methods: A cross-sectional study was conducted with 61 patients with bulbar- or spinal-onset ALS. The dietary intake of B vitamins (B1, B2, B6, B12, folate, and niacin); vitamins C, A, D, and E; and the B6/protein ratio were assessed using a seven-day dietary record and a Food Frequency Questionnaire. Blood concentrations of butyrylcholinesterase (BuChE), albumin, haptoglobin, C-reactive protein (CRP), and paraoxonase 1 (PON1) were determined. Basal muscle activation was measured using surface electromyography of the biceps brachii, triceps brachii, rectus femoris, and tibialis anterior muscles. Two confirmatory predictive models were developed to evaluate the effects of muscle damage and vitamin intake on muscle strength. Results: Arm muscle activation was negatively predicted by the B6/protein ratio (β = −0.33). Leg activation was positively predicted by vitamin B9 (β = 0.39) and B6/protein (β = 0.17) and negatively predicted by vitamin A (β = −0.24). For biomarkers, albumin (β = 0.18) and PON1 (β = 0.28) positively predicted activation. For legs, albumin predicted activation (β = 0.31), whereas BuChE and haptoglobin predicted negative activation (β = −0.32 and β = −0.15, respectively). Conclusions: Weak associations were observed in patients with ALS: vitamin B9 intake showed a modest association with leg activation, the B6/protein ratio exhibited inconsistent associations across muscle groups, and vitamin A showed a negative association with leg activation. Albumin demonstrated the most consistent association as a potential biomarker of muscle function. These findings are exploratory and require validation in larger, longitudinal studies. Full article

Broadcast-style downlinks (e.g., PONs and satellites) expose physical waveforms despite transport-layer cryptography, motivating physical-layer encryption (PLE). Digital chaotic encryption is appealing for its noise-like spectra, sensitivity, and DSP-friendly implementation, but in low-CSPR KK-SSB systems, common embeddings disrupt minimum-phase requirements and raise PAPR/SSBI near 1 dB CSPR, while finite-precision effects can leak correlation after KK reconstruction. We bridge this gap by integrating 3D Lorenz-based PLE into our low-CSPR KK-SSB receiver. A KK-compatible embedding applies a Lorenz-driven XOR mapping to I/Q bitstreams before PAM4-to-16QAM modulation, preserving the minimum phase and avoiding spectral zeros. Co-design of chaotic strength and subband usage with the KK SSBI-suppression method maintains SSBI mitigation with negligible PAPR growth. We further adopt digitization settings and fractional-digit-parity-based key derivation to suppress short periods and remove key-revealing synchronization cues. Experiments demonstrate a 10⁹¹ key space without degrading transmission quality, enabling secure, key-concealed operation on shared downlinks and offering a practical path for chaotic PLE in near-minimum-CSPR SSB systems. Full article