Search Results (143)

The use of analog radio-over-fiber (RoF) systems combined with power-over-fiber (PoF) systems has been proposed in recent years for applications involving remote sensors used in hazardous environments or where electrical wiring may be impractical. This article presents a hybrid architecture topology that combines PoF and RoF, using Raman amplification to obtain RF gain. The first emphasis is placed on the use of two types of high-power laser sources (HPLSs) for the PoF system: a 1480 nm Raman-based HPLS and a 1550 nm HPLS that is based on an erbium-doped fiber amplifier (EDFA). The second emphasis of this paper is on how these two HPLSs simulate Raman scattering (SRS) in the fiber, considering different lengths of SMF 28 for the link. Thus, a comparative analysis is proposed considering the effects induced on the RF signal, mainly focused on its RF power gain ($G_{RF}$), noise figure (NF), and spurious-free dynamic range (SFDR). The obtained results show that the architecture using a PoF system based on the 1550 nm HPLS benefits from a lower noise figure degradation, even when the noise generated by the optical amplification is considered. Full article

Integrated photonics is a transformative technology for enhancing communication and computation in Cloud and Fog computing networks. Photonic integrated circuits (PICs) enable significant improvements in data-processing speed, energy-efficiency, scalability, and latency. In Cloud infrastructures, PICs support high-speed optical interconnects, energy-efficient switching, and compact wavelength division multiplexing (WDM), addressing growing data demands. Fog computing, with its edge-focused processing and analytics, benefits from the compactness and low latency of integrated photonics for real-time signal processing, sensing, and secure data transmission near IoT devices. PICs also facilitate the low-loss, high-speed modulation, transmission, and detection of RF signals in scalable Radio-over-Fiber (RoF) links, enabling seamless IoT integration with Cloud and Fog networks. This results in centralized processing, reduced latency, and efficient bandwidth use across distributed infrastructures. Overall, integrating photonic technologies into RoF, Fog and Cloud computing networks paves the way for ultra-efficient, flexible, and scalable next-generation network architectures capable of supporting diverse real-time and high-bandwidth applications. This paper provides a comprehensive review of the current state and emerging trends in integrated photonics for IoT sensors, RoF, Fog and Cloud computing systems. It also outlines open research opportunities in photonic devices and system-level integration, aimed at advancing performance, energy-efficiency, and scalability in next-generation distributed computing networks. Full article

Intervertebral disc disease is the most common disease of the spine in dogs and is a main cause of pain and neurologic dysfunction. This article reviews fundamental aspects of the pathophysiology, clinical presentation, diagnosis, and treatment of disc extrusions. Chondroid metaplasia of the nucleus pulposus is the central mechanism of disc degeneration. The clinical presentation varies considerably, depending on the breed, the location of the disc extrusion, and the degree of neurological damage. Advanced imaging techniques, such as computed tomography and magnetic resonance imaging, have greatly improved diagnosis, with magnetic resonance considered the gold standard. As for treatment, both medical and surgical management are effective options, depending on the degree of neurological damage and the initial response to conservative treatment. This comprehensive analysis underlines the importance of a multidisciplinary approach to optimize the quality of life of patients affected by intervertebral disc disease. Full article

High demand for 6G wireless has made photonics-aided D-band (110–170 GHz) communication a research priority. Photonics-aided technology integrates optical and wireless communications to boost spectral efficiency and transmission distance. This study presents a Radio-over-Fiber (RoF) communication system utilizing photonics-aided technology for 4600 m long-distance D-band transmission. We successfully show the transmission of a 50 Gbps (25 Gbaud) QPSK signal utilizing a 128.75 GHz carrier frequency. Notwithstanding these encouraging outcomes, RoF systems encounter considerable obstacles, including pronounced nonlinear distortions and phase noise related to laser linewidth. Numerous factors can induce nonlinear impairments, including high-power amplifiers (PAs) in wireless channels, the operational mechanisms of optoelectronic devices (such as electrical amplifiers, modulators, and photodiodes), and elevated optical power levels during fiber transmission. Phase noise (PN) is generated by laser linewidth. Despite the notable advantages of classical Volterra series and deep neural network (DNN) methods in alleviating nonlinear distortion, they display considerable performance limitations in adjusting for phase noise. To address these problems, we propose a novel post-processing approach utilizing a two-dimensional convolutional neural network (2D-CNN). This methodology allows for the extraction of intricate features from data preprocessed using traditional Digital Signal Processing (DSP) techniques, enabling concurrent compensation for phase noise and nonlinear distortions. The 4600 m long-distance D-band transmission experiment demonstrated that the proposed 2D-CNN post-processing method achieved a Bit Error Rate (BER) of 5.3 × 10⁻³ at 8 dBm optical power, satisfying the soft-decision forward error correction (SD-FEC) criterion of 1.56 × 10⁻² with a 15% overhead. The 2D-CNN outperformed Volterra series and deep neural network approaches in long-haul D-band RoF systems by compensating for phase noise and nonlinear distortions via spatiotemporal feature integration, hierarchical feature extraction, and nonlinear modelling. Full article

Serum beta-hydroxybutyrate (BHB) and non-esterified fatty acids (NEFAs) are biomarkers of situations of negative energetic balance in bovine. However, knowledge about their possible measurement and use in saliva is limited. In this report, two commercially available methods for the measurement of BHB and NEFAs were validated for use in bovine saliva. Both methods showed good precision and accuracy. The BHB concentrations were correlated between the saliva and the serum, but not the NEFA concentrations. The cows with hyperketonemia (n = 17) had increased salivary BHB compared to the cows with no clinical signs and no hyperketonemia (n = 34) and those with clinical signs of metritis (n = 17). The salivary NEFA concentration increased in newborn calves (n = 10) on days 1 and 2 of life compared to the day of birth before colostrum intake. The calves with symptomatic bovine respiratory disease complex (BRD, n = 7) showed higher salivary NEFA concentrations than those without clinical symptoms (n = 6). Thus, BHB and NEFAs can be reliably measured in bovine saliva using easily automatable colorimetric methods. Salivary BHB increased in hyperketonemia and could be a potential biomarker of this condition. Further studies should be undertaken to clarify the mechanism and possible use of salivary NEFAs as biomarkers. Full article

One of the physical requirements for marines involves covering a specific distance while carrying individual combat gear, supplies, or other military equipment across challenging terrain. Training for this physically and mentally demanding task is a routine component of their preparation. However, further research is needed to better understand the neuromuscular impact of such demanding efforts, strenuous maneuvers, and the recovery process in the subsequent days. Twenty-nine marines completed a 5 km time trial while carrying 24 kg of combat gear, undergoing evaluations at four time points: pre exercise, immediately post exercise, 24 h post exercise, and 48 h post exercise. Repeated measures ANOVA, paired samples t-test, and effect size (ES) analysis were conducted, presenting the results as the mean ± standard deviation (SD). The significance level was set at p ≤ 0.05. Several variables and their corresponding p-values demonstrated changes over time, including the following: the isometric mid-thigh pull (IMTP) (p = 0.001); countermovement jump height (VJ CMJ) (p ≤ 0.001); rating of fatigue scale (ROF) (p ≤ 0.001); blood lactate (BL) levels (p ≤ 0.001); maximum pull-ups (PUmax) (p ≤ 0.001); body mass (BM) (p ≤ 0.001); dominant hand grip strength (DHGS) (p = 0.406); and non-dominant hand grip strength (NDHGS) (p = 0.805). Incident reports and perceived effort (IRPE) revealed a progressive and significant increase between the first and last kilometer of the test, specifically in perceived variables of fatigue, muscle pain, joint pain, shortness of breath, palpitations, excessive sweating, and muscle tremors (all p ≤ 0.001). These findings may contribute to optimizing training programs to better align with operational demands, thereby improving task performance and overall mission effectiveness. In conclusion, the military test had a significant neuromuscular impact on the body, initially resulting in the potentiation of absolute global isometric strength and lower-limb power. However, these values declined below the baseline levels at 24 and 48 h post test. Full article

Data centers are a part of the digital economy, but they are great contributors to energy use and carbon emissions. The site selection for data centers can, therefore, be an important tool in the optimization of energy efficiency and sustainability, especially in those areas where climatic and infrastructural factors can keep environmental impacts as low as possible. This study will evaluate seven possible sites for a data center in Turkey, focusing on high-altitude ski resorts with natural cooling advantages. In the paper, the research uses q-Rung Orthopair Fuzzy Numbers (q-ROFs) in combination with methods like Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and VIseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR), taking environmental, technical, and socio-economic criteria into consideration, such as energy efficiency, disaster risk, infrastructure quality, and accessibility. To strengthen result reliability, a sensitivity analysis by varying the q parameter and a comprehensive study by performing different multi-criteria decision-making (MCDM) methods were employed. Analysis revealed that Erciyes and Uludağ consistently ranked among the top alternatives across all methods and q values, indicating their robustness. The results confirm the effectiveness of the proposed methodology in supporting sustainable and high-altitude-aware site selection decisions. This research presents a holistic and Sustainable Site Selection framework for data centers; therefore, it provides actionable insights into stakeholders who balance operational efficiency with environmental responsibility. Future studies should subsequently delve into dynamic modeling and global applications to enhance the versatility of the framework. Full article

A novel system to generate and transmit frequency 16-tupling millimeter waves (MMWs) without the bit walk-off effect created by the Mach–Zehnder modulator (MZM) is proposed. The ±8th-order sidebands are generated by four MZMs connected in parallel with the data carried only on the +8th-order sideband by adopting the composite radio frequency (RF) for the MZMs. The frequency 16-tupling MMW with data is generated by injecting the ±8th order sidebands into the photodetector. The system’s principle of operation is given. The feasibility of our designed schemes is verified by the simulation experiment. The effect on the system’s BER is discussed when the main parameters diverge from their theoretical values or default values. Our designed system can effectively eliminate the bit walk-off effect caused by fiber dispersion and greatly raise the fiber distribution distance. Full article

Cranial cruciate ligament rupture is the most common orthopedic condition in dogs, causing lameness, joint instability, and discomfort due to its role in knee stability. Surgical treatment, particularly osteotomies in the proximal tibia, is the preferred approach, with tibial tuberosity advancement (TTA), tibial plateau leveling osteotomy (TPLO), and the modified Maquet technique (MMT) being widely used. A common postoperative complication is patellar desmopathy—thickening of the ligament that is detectable on radiographs and can cause further discomfort. However, studies on this complication in TPLO are limited, and there are no direct comparisons of ligament thickening between these surgical techniques. This study aimed to determine the prevalence of ligament desmopathy in TPLO, examine any associations with age, sex, or weight, and compare findings with those from other techniques. A retrospective analysis was conducted, with ligament thickness measured at three points during postoperative follow-up, which had a mean of approximately 2.5 months. Results showed an 86.7% prevalence of desmopathy, with average thicknesses of 3.90 mm proximally, 4.69 mm at mid-ligament, and 5.98 mm distally. These findings align with previous TPLO studies and suggest that TPLO may cause greater ligament thickening than TTA or MMT, particularly in the distal portion. Full article

The objective of this study was to evaluate the effects of trazodone as part of premedication in routine surgical procedures. A prospective, randomized, double-blinded clinical study was conducted on 16 adult female dogs undergoing elective ovariectomy. Behavioral responses were assessed after oral administration of trazodone (5 mg/kg) in eight dogs and compared with a control group (n = 8). Sedation levels at the time of induction and the required dose of propofol were recorded. Additionally, intraoperative fentanyl IV boluses (2.5 µg/kg) administered in response to surgical pain, along with heart rate (HR) and non-invasive arterial pressure (NIAP), were compared between groups. Dogs receiving trazodone exhibited significantly lower stress scores on the Clinic Dog Stress Scale (CDSS) and fewer episodes of vomiting after premedication, and they required lower doses of both propofol and intraoperative analgesia. These findings suggest that oral trazodone administration two hours before hospital arrival may help reduce preoperative stress in dogs undergoing elective ovariectomy. However, further studies with larger sample sizes are needed to confirm these results and fully evaluate the role of trazodone in preoperative protocols. Full article

Infantry soldiers must cover long distances carrying heavy and bulky combat equipment. Since the beginning of their training, Spanish Marines have undergone this characteristic and demanding test. However, little is known about its effects on neuromuscular function and recovery in the days following the test. Twenty-six Spanish Marines completed the test, three of whom suffered injuries and had to withdraw from the study, resulting in a final sample of twenty-three Marines. These participants underwent evaluations before (pre), immediately after (post), and 24 and 48 h post-exercise, following a 30 km endurance march carrying their 34 kg combat equipment. A repeated-measures ANOVA, paired-samples t-test, and effect size (ES) analysis were conducted; the results are presented as mean ± SD. The significance level was set at p ≤ 0.05. The variables and p-values of changes over time are presented. Isometric mid-thigh pull (IMTP) (p = 0.004), countermovement jump (CMJ) (p ≤ 0.001), rating of fatigue scale (ROF) (p ≤ 0.001), maximum pull-ups in two minutes (PUmax) (p ≤ 0.001), body mass (BM) (p ≤ 0.001), hand grip strength (HGS): dominant (p = 0.180) and non-dominant (p = 0.616), and incident reports (IRPE) showed a significant increase over time and between the first 10 km and last 5 km in fatigue, muscle pain, joint pain, shortness of breath, excessive sweating (p ≤ 0.001), and muscle tremors (p = 0.028), except for palpitations (p = 0.189). In conclusion, the results indicate that the test had a significant impact on neuromuscular function, with no recovery observed in overall strength and lower limb power after 48 h, even though their perceived fatigue decreased substantially. The resilient spirit of operational military units and their philosophy of always being ready for combat could increase the injury rate. Full article

Edible flowers (EFs) form a special group of food plants that serve a pivotal role in local food systems, both in their utilitarian value and cultural significance. Dali, renowned for its rich biocultural diversity, is home to various ethnic groups with unique traditions regarding the consumption of EFs. However, systematic and comprehensive ethnobotanical studies of EFs are lacking, and their biocultural significance has not been discussed. Through ethnobotanical surveys conducted in 15 markets across Dali, 163 taxa of EFs were documented, encompassing 56 families and 108 genera. They were consumed in 16 ways and as 5 types of food. Quantitative evaluations using the Relative Occurrence Frequency (ROF) and Cultural Food Significance Index (CFSI) assessed the local importance of these flowers. Comparisons were made with another site regarding flower-eating species and methods, revealing biocultural differences. The study highlights how these flowers contribute to local dietary practices and cultural traditions. The role of EFs in sustainable food systems (SFS) is discussed, with emphasis on their economic, environmental, and social impacts. Protecting biocultural diversity means maintaining reciprocal relationships between people and edible species, which are crucial nodes in local SFS. Full article

Visible-light communication (VLC) has emerged as a promising technology to provide the very high-throughput wireless communications demanded by beyond-fifth-generation (B5G) applications. However, few works are found in the literature regarding the integration of VLC systems with other wireless communications technologies and with access networks. In this context, and as a proof of concept, we implement and experimentally evaluate a hybrid network architecture based on VLC, radio-over-fiber (RoF), free space optics (FSO), fiber-wireless (FiWi), and millimeter-waves (mm-waves) for B5G applications. Such optical networks make use of fiber-optic links based on RoF technology as backhauls, whereas their fronthauls might be either by FSO or RoF. Finally, a triple-wireless-access network is ensured by VLC, FiWi, and mm-wave links. The latter use a real 5G new radio (5G NR) signal. The system performance is evaluated in terms of a root mean square error vector magnitude (EVM_RMS) parameter in accordance with the 3rd-Generation Partnership Project (3GPP) requirements. The experimental results demonstrate a total maximal theoretical throughput of approximately 1.66 Gbps, aligning with the digital performance requirements set by 3GPP. Full article

Road traffic accident severity prediction is crucial for implementing effective safety measures and proactive traffic management strategies. Existing methods often treat this as a nominal classification problem and use traditional feature selection techniques. However, ordinal classification methods that account for the ordered nature of accident severity (e.g., slight < serious < fatal injuries) in feature selection still need to be investigated thoroughly. In this study, we propose a novel approach, the Ordinal Random Tree with Rank-Oriented Feature Selection (ORT-ROFS), which utilizes the inherent ordering of class labels both in the feature selection and prediction stages for accident severity classification. The proposed approach enhances the model performance by separately determining feature importance based on severity levels. The experiments demonstrated the effectiveness of ORT-ROFS with an accuracy of 87.19%. According to the results, the proposed method improved prediction accuracy by 10.81% over state-of-the-art studies on average on different train–test split ratios. In addition, it achieved an average improvement of 4.58% in accuracy over traditional methods. These findings suggest that ORT-ROFS is a promising approach for accurate accident severity prediction, supporting road safety planning and intervention strategies. Full article

Background: Hepatocellular carcinoma (HCC) is the most prevalent malignant tumor, ranking fifth in terms of fatality with poor prognosis and a low survival rate. Rhoifolin (ROF), a flavonoid constituent, has previously been shown to suppress the proliferation of breast and pancreatic cancer cells. However, its inhibitory effect on HCC has remained unexplored. Objectives: Exploring the potent inhibitory activities and underlying mechanisms of ROF on HCC cells. Methods: The suppressive effect of ROF on HCC cells were assessed via CCK8 assay, apoptosis assay, cell cycle analysis and xenograft tumor mouse model. Furthermore, quantitative real-time PCR and western blot were applied to analyze the underlying mechanisms of ROF on HCC cells. Results: Firstly, the IC₅₀ values of ROF in HepG2 and HuH7 cells were 373.9 and 288.7 µg/mL at 24 h and 208.9 and 218.0 µg/mL at 48 h, respectively. Moreover, the apoptosis rates of HepG2 and HuH7 cells increased from 6.63% and 6.59% to 17.61% and 21.83% at 24 h and increased from 6.63% and 6.59% to 30.04% and 37.90% at 48 h, respectively. Additionally, ROF induced cell cycle arrest at the S phase in HCC cells. Furthermore, ROF suppressed the tumor growth of HCC cells in vivo without obvious toxicity. Mechanically, ROF facilitated apoptosis by upregulating the expression of PIDD1, CASP8, CASP9, BID, BAX, BIM, and BAK1 in HCC cells. Conclusions: ROF significantly restrains the growth of HCC cells in vitro and in vivo, which could be an effective supplement for HCC therapy. Full article