Search Results (336)

Background and Objectives: Candiduria is a common health problem especially among hospitalized patients. In the era of rising azole resistance, evidence from Saudi Arabia remains limited concerning Candida species. This study aimed to assess the prevalence and risk factors of Candida isolated from urine culture and to explore species distribution in relation to clinical characteristics. Materials and Methods: We retrospectively reviewed 188353 urine samples from 2013 to 2023. Using medical records, data on age, gender, hospitalization status, and urine sample type were collected. Identification of Candida species was performed by VITEK Mass Spectrometry (bioMerieux Inc.). Binary logistic regression analysis was used to identify predictors of candiduria. A p value below 0.05 at a 95% CI was considered statistically significant. Results: A total of 1667 urine samples with significant Candida growth were reported. It accounted for 0.88% of all organisms grown from urine culture and 30% of Candida grown from various body sites. Candida albicans was the most frequently identified species (n = 920, 55.2%), followed by C. tropicalis (n = 374, 22.4%), C. krusei (n = 80, 4.8%), C. glabrata (n = 78, 4.7%), and C. parapsilosis (n = 41, 2.5%). However, the rate was not stable throughout the years, and non-albicans Candida (NAC) was often the most prevalent. Female gender was the strongest predictor of candiduria (OR and AOR 1.81, 95% CI 1.46–2.25), whereas significantly lower odds were seen in elderly patients and in random urine specimens. The species distribution of NAC did not seem to change with age, gender, type of specimen, or hospitalization status. Conclusions: Among all Candida spp. isolated in the lab, 30 out of every 100 originated from urine culture, with a significant risk associated with females. The increasing prevalence of emerging Candida species in tertiary care settings can provide clinicians with valuable insights for the diagnosis and management of Candida UTI. Full article

Cheese whey, a byproduct of the dairy industry, has a high organic load and nutrient availability, associated with parameters such as chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP), representing an environmental problem when improperly disposed, and even considering the traditional biological wastewater treatment (secondary treatment), a polishing step (tertiary treatment) could be required in order to meet legislation parameters of discharge in water bodies. This study evaluated the efficiency of co-cultivation between the microalga Tetradesmus obliquus and the yeast Saccharomyces cerevisiae during the tertiary (advanced) treatment of dairy effluent. The process was operated in batch mode to optimize the COD:N ratio and, subsequently, in semicontinuous mode applying the volumetric replacement rates (VRRs) of 40% and 60%. In the batch stage, the COD:N ratio of 20 stood out as the most balanced in terms of nutritional requirement, achieving removal rates of 85.49% for COD, 96.23% for total Kjeldahl nitrogen (TKN), and 100% for TP. In the semicontinuous system, a VRR of 40% optimized nitrogen (91.67%) and phosphorus (95.93%) recovery while COD was also removed (71.68%). The pH remained stable within the range of 7.0 to 7.5 at the end of the process, indicating self-buffering of the consortium. Biomass production reached 915 mg·L⁻¹ (dry cell weight) in batch operation mode and 720 mg·L⁻¹ in semicontinuous mode (VRR of 40%). The results confirmed that the T. obliquus and S. cerevisiae co-cultivation constitutes a stable and sustainable strategy for nutrient recovery during dairy wastewater treatment, aligning with the principles of circular bioeconomy. Full article

The N-body problem is a classic problem involving a system of N discrete bodies mutually interacting in a dynamical system. At any moment in time there are $N(N-1)/2$ such interactions occurring. This $N^2$ scaling leads to computational difficulties where simulations range from tens of thousands of bodies to billions or trillions. Approximation algorithms, such as the famous Barnes–Hut algorithm, simplify the number of interactions to scale as $NlogN$. Even still, this improvement in complexity is insufficient to achieve the desired performance for very large simulations on computing clusters with many nodes and many cores. In this work we explore a variety of algorithmic techniques for parallel and distributed variations on the Barnes–Hut algorithm to improve parallelism and reduce inter-process communication requirements. This includes the costzones and hashed octree techniques. We implement these techniques in a gravitational N-body simulation and show that they can be applied to both a parallel and distributed context. This work collects and unifies over 30 years of research, while filling in missing details, to provide a comprehensive and reproducible source. Full article

Central configurations are fundamental equilibrium solutions of the Newtonian n-body problem and play a key role in understanding the structure and dynamics of gravitational systems. However, the classification and enumeration of such configurations remain incomplete in the four-body case, particularly for symmetric configurations. In this work, we develop a framework for determining and classifying symmetric four-body Dziobek configurations. The method allows the explicit determination of the number of admissible configurations directly from the mass parameters, without requiring prior knowledge of their geometric structure. Combined with previously established semi-analytical relations, this approach provides a systematic characterization of symmetric configurations in terms of mass ratios. As a physically relevant application, we apply the framework to the Earth–Moon system and determine the possible symmetric four-body central configurations involving Earth- and Moon-mass bodies and an additional object of arbitrary mass. We identify both isolated configurations and continuous families of equilibrium solutions, extending the concept of libration points to the four-body problem. The presented semi-analytical approach contributes to the understanding of equilibrium structures in multi-body gravitational systems and provides a foundation for further studies in celestial mechanics, planetary dynamics, and spacecraft motion in complex gravitational environments. Full article

Background/Objective: Health is a multidimensional construct shaped not only by clinical conditions but also by psychological, social, environmental and cultural factors. In low- and middle-income countries undergoing rapid epidemiological transition, understanding health requires integrated and culturally informed approaches. However, quality of life, perceived health status and lifestyle behaviors are often investigated separately, limiting the interpretation of well-being in specific local contexts. This study aimed to provide an integrated assessment of quality of life, perceived health status and lifestyle behaviours among adults attending a peri-urban public hospital in Kenya, using internationally validated instruments applied within a specific local cultural context. Methods: A cross-sectional observational study was conducted at Tigoni Level 4 Hospital, Kiambu County, Kenya. Adult outpatients (N = 40) were consecutively recruited. Quality of life was assessed using the WHOQOL-BREF, perceived health status using the EQ-5D-5L and EQ-VAS, and lifestyle behaviours using selected modules of the WHO STEPS instrument. Descriptive statistics were performed, and exploratory associations were examined using Spearman’s rank correlation coefficient. Results: Participants had a mean age of 35.9 ± 11.4 years, with a balanced gender distribution. Lifestyle risk factors were prevalent, including insufficient physical activity (40%) and overweight or obesity (>50%). WHOQOL-BREF scores revealed a heterogeneous profile, with relatively preserved social relationships and lower scores in the psychological and environmental domains. Pain/discomfort and anxiety/depression were the most frequently reported EQ-5D-5L problems. The mean EQ-VAS score was 68.2 ± 15.7. Perceived health was positively associated with physical and psychological quality of life, while higher body mass index was associated with lower physical quality of life. Mental health emerged as a cross-cutting factor across instruments. Conclusions: The findings highlight the multidimensional nature of health in a peri-urban Kenyan context and suggest the importance of considering local social and cultural influences when interpreting standardized health measures. Mental health and environmental conditions play a central role in shaping quality of life and perceived health, while lifestyle risk factors are already prevalent in a relatively young outpatient population. Integrating standardized health measures within a cross-cultural framework may support more holistic and person-centred approaches in primary care and public health in similar settings. Full article

A cross-sectional study was carried out on small-scale dairy farms in Paraíba State, Brazil, to evaluate the prevalence and anatomical distribution of integument injuries in grazing dairy cows. Twelve herds (n = 12) were assessed, recording herd size, milk yield, and daily hours of pasture access. The integument of five body regions (back/shoulder/neck, carpus, flank/side/udder, tarsus, and hindquarters) was scored for hairless spots, lesions, and swellings (0 = absent; 1 = present). Among 335 cows observed, 267 (81.5%) presented at least one injury. The most frequent conditions were hairless patches on the hock (65.4 ± 5.03%), lesions on the flank/side/udder (34.5 ± 1.46%), and swelling in the back/shoulder/neck region (52.9 ± 5.86%). Cluster analysis revealed distinct patterns of integument injuries among cows. The high prevalence of integument injuries indicates that even in grazing systems, welfare concerns persist. Neck swelling and hairless spots on the hock were the most common problems, emphasizing the need for improved management and environmental practices to enhance welfare outcomes. These findings have practical implications for welfare assessment and management strategies in tropical grazing dairy systems. Full article

A compliant constant-force mechanism (CCFM), known for its frictionless, contact-free operation and inherently constant output, is typically limited to a single force range, restricting its adaptability to multi-task applications. To address this problem, in this study, we propose a dual-stage compliant constant-force mechanism (DSCCFM) that delivers a continuous dual-range constant-force output within a monolithic structure. The design integrates a Z-shaped beam with a bistable beam and a bistable rhombic beam, thereby forming the DSCCFM. By integrating the pseudo-rigid-body model (PRBM) with the chained-beam constraint model (CBCM), a theoretical model of the DSCCFM is established. Using a finite-element response surface model and multi-objective genetic algorithm (MOGA) optimization, the constant-force stroke was improved by approximately $38\%$ over the initial design. The experiments confirm stable outputs of 6.72 N and 21.91 N across the 2–5.8 mm and 11.6–14.8 mm ranges, respectively. The DSCCFM effectively supports multi-stage force execution, cell gripping, and micro/nano-scale manipulation. Full article

Wheeled multifunctional motorized crossing frames represent a new type of crossing equipment for high-voltage transmission line construction. The initial design is too conservative, having a large safety margin and high material redundancy. Therefore, it is necessary to study a lightweight design version. However, as the structure constitutes an assembly consisting of multiple components, it also exhibits relatively high complexity. In a lightweight design, optimizing multi-component and multi-size parameters can lead to structural interference and separation, seriously affecting the smooth progress of design optimization. Therefore, an optimization design method of a multi-parameter complex assembly structure is proposed to solve this problem. Firstly, the typical stress conditions of the wheeled multifunctional motorized crossing frame were analyzed using its structural model. Then, a finite element model of the beam was established in ANSYS 2021 R1 Workbench, and the mechanical characteristics were analyzed. The results show that the arm support is the key load-bearing component and has significant optimization potential. Subsequently, functional mapping relationships were established among the 14 dimension parameters of the arm support, reducing the number of design variables to six and successfully avoiding component separation or interference during optimization. Through global sensitivity analysis, the height, thickness, and length of the arm body were screened out as the core optimization parameters from six initial design variables. Then, 29 groups of sample points were generated via central composite design (CCD), and a response surface model reflecting the relationships among the arm body’s dimensional parameters, total mass, maximum stress, and maximum deformation was established using the Kriging method. Leave-one-out cross-validation (LOOCV) was performed, and the coefficients of determination (R²) for model fitting were all higher than 0.995, indicating extremely high prediction accuracy. Taking mass and deformation minimization as the optimization objectives, the MOGA algorithm was adopted to perform multi-objective optimization and determine the optimal engineering parameters. Simulation verification was conducted on the optimized arm support, and an eigenvalue buckling analysis was performed simultaneously to verify structural stability. Finally, the proposed optimization method was experimentally verified through mechanical performance tests of the full-scale prototype under symmetric and eccentric loads. The results show that the mass of the optimized arm support is reduced from 217.73 kg to 189.8 kg, with a weight reduction rate of 12.8%. Under an eccentric load of 70,000 N, the maximum deformation of the arm support is 8.9763 mm, the maximum equivalent stress is 314.86 MPa, and the buckling load factor is 6.08, all of which meet the requirements for structural stiffness, strength, and buckling stability. The maximum error between the experimental and finite element results is only 4.64%, verifying the accuracy and reliability of the proposed method. The proposed optimization methodology, validated on a wheeled multifunctional motorized crossing frame, serves as a transferable paradigm for the lightweight design of complex assemblies with coupled dimensional constraints, thereby offering a general reference for the structural optimization of multi-component transmission line equipment, construction machinery, and other multi-component engineering systems. Full article

We present an ab initio study on the one-neutron halo nucleus ¹¹Be using nuclear lattice effective field theory with high-fidelity chiral interactions at N3LO. By employing the wavefunction matching method to mitigate the sign problem and the pinhole algorithm to sample many-body correlations, we successfully reproduce the ground-state parity inversion and the extended matter radius characteristic of the halo structure. We analyze the intrinsic density distributions and geometric shapes of ¹¹Be in comparison with the core nucleus ¹⁰Be. Our results reveal a prominent two-cluster structure in both nuclei and the occupation of the $\sigma$ molecular orbital by the valence neutron in ¹¹Be. It enhances the prolate deformation as well as the diffuse neutron tail, distinct from the $\pi$-orbital occupation observed in the ¹⁰Be ground state. Full article

The feather coverage of a laying hen is an important indicator of both its productivity and welfare. Conventional manual feather scoring procedures are laborious, subjective, and stressful for the hens. Thermography offers a modern alternative to addressing these problems. Thermal cameras capture radiative heat loss, which is comparatively greater Classification from featherless areas. Studies have been conducted to establish a standard temperature range that correlates to specific featherless areas. However, such temperature-based approaches have been inconsistent with each other. In contrast, this study used deep learning techniques to automatically assess dorsal feather scores using thermal images. Thermal images (n = 1575) of the dorsal body of cage-free laying hens with varying degrees of feather damage were captured. Manual feather scoring was performed, classifying the image into a feather score (0–2) according to the increasing severity of feather loss. A total of 1222 images were selected, filtering out images of lower quality. Two types of computer vision models, a classification model and an object detection model, were trained and evaluated. A custom convolutional neural network (CNN) was trained to classify thermal images into feather score categories. Additionally, we trained and optimized You Only Look Once (YOLO) object detection models to detect areas of feather damage and predict the feather score. The CNN model achieved an overall accuracy of 0.81, with high precision for severe feather loss. The YOLO-based object detection model was optimum using YOLO11n, which achieved a precision of 0.81, a recall of 0.73 and a mean average precision (mAP) at 0.5 intersection over union (IoU) of 0.84. Results show the potential of combining thermal imaging with deep learning techniques to perform objective, automatic, and scalable feather scoring procedures. Future studies should focus on data diversity, multiple part scoring, and semantic segmentation for robust performance. Full article

A program package for calculating regularized classical trajectories for Coulomb n–body problem is developed. The Coulomb singularities from the equations of motion are removed by transformations of variables including the time. This effectively conserves the energy of the time-independent systems to a high accuracy for long time propagation. Sample calculations are shown for the cases of 2, 3, 4, and 5 particle systems giving comparisons with the un-regularized trajectories. The program can be used for general purposes including the classical-trajectory Monte-Carlo simulations for charged-particle collisions in free or laser environments. Full article

Plastic pollution is acknowledged as a serious problem for ecosystems. Among these plastics, polystyrene nanoplastics (PS-NPs) are emerging environmental pollutants, and their biological effects on hepatotoxicity are the least explored. Therefore, the present work examined the effect of PS-NPs on the hepatic transcription of the antioxidant genes Hmox1 and Sod3 in mice (n = 6, treatment (PS-NPs) vs. vehicle group (Veh)), mediated by RORγ and epigenetic modifications. The results show that PS-NP mice had significantly reduced body weight; increased activity of adenosine triphosphate (ATP), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH), and Complexes I, III, and V in the liver; and increased Alanine Transaminase (ALT), Aspartate Transaminase (ASP), Alkaline Phosphatase (ALP), malondialdehyde (MDA) and reactive oxygen species (ROS) compared to the Veh group. Furthermore, PS-NPs resulted in considerably lower relative mRNA expression of Hmox1, Sod3, and RORγ in the liver than the Veh group. Likewise, when compared to Veh, PS-NPs significantly reduced the enrichment of RORγ, as well as the occupancies of the key components of the transcriptional activation pathway (P300, SRC1, Pol II, Ser5-Pol II, and Ser2-Pol II) at the loci of Hmox1 and Sod3. In comparison to Veh, PS-NPs showed downregulated occupancies of the histone active marks H3K9ac and H3K18ac, while H3K4me3 and H3K27me3 were higher at the target loci of Hmox1 and Sod3. In conclusion, the present study highlights that PS-NPs induce oxidative stress by modifying Hmox1 and Sod3 in mice’s livers through histone changes and nuclear receptor RORγ modulation. Full article

The presence and development of pathogens in the human body remains a serious problem. The existence of microorganisms is primarily related to their ability to adhere to various surfaces. The aim of this study was to evaluate the ability of Si(C,N) coatings on a nickel-chromium alloy surface to reduce bacterial and fungal adhesion and to provide antimicrobial activity. This publication also focused on determining which coating variant is most effective in reducing microbial adhesion. Si(C,N) coatings were sputtered onto the surface of the prosthetic alloy using the magnetron sputtering method. Observation was performed using a fluorescence microscope and a flow cytometer. The number of adhered bacterial cells decreased compared to the samples without coating (sample series A) by approximately 84% in sample series B and by 29% in sample series F. In the case of adhesion of fungal cells, their number decreased compared to the samples without coating (sample series A) by approximately 76% in sample series B and by 47% in sample series F. The applied one-way analysis of variance test indicated a statistically significant effect of the tested factor at a level below 0.001. Based on the conducted research, it was noticed that the use of Si(C,N) layers on the surface of the prosthetic alloy limits the adhesion of bacteria and fungi. Full article

Background/Objective: The anterior vertebral body tethering (AVBT) technique, which preserves spinal mobility and avoids possible fusion problems in adolescent idiopathic scoliosis (AIS) patients, continues to be increasingly used in spine surgery. The study aims to report the early-to-early-mid postoperative radiological results of thoracolumbar/lumbar AVBT on sagittal alignment, and the second aim is to compare AVBT with selective thoracic fusion (STF) and non-selective fusion (NSF) groups in AIS patients. Methods: Patients with a diagnosis of AIS were retrospectively evaluated in the study. All patients were categorized into three groups based on the surgical technique performed: AVBT (n = 17), NSF (n = 19), and STF (n = 15). The major curvature degree, coracoid height difference (CHD), sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI), lumbar lordosis (LL), thoracic kyphosis (TK), cervical lordosis (CL), C7 tilt, sagittal vertical axis (SVA), T1 pelvic angle (TPA), and T1 spinopelvic inclination (T1SPI) were measured for radiological comparison. Scoliosis Research Society-22 (SRS-22) and Oswestry Disability Index (ODI) scores were used at the final follow-up for functional evaluation. Results: The T1SPI value of the NSF group was significantly higher than the STF group in the final follow-up (p = 0.033). The mean decrease of 8.85 ± 7.85 units in the final follow-up value compared to the postoperative CHD value of the patients in the AVBT group was found to be significant (p = 0.028). Statistically significant differences were found between preoperative and the first postoperative CL and TPA measurements (p = 0.001 and p = 0.042, respectively), as well as between preoperative and final follow-up CL measurements in the AVBT group (p = 0.001). No statistically significant differences were observed between the groups in CHD, SS, PT, PI, LL, TK, CL, C7 tilt, SVA, and TPA values (p > 0.05); similarly, the SRS-22 and ODI scores did not differ significantly among the groups (p > 0.05). Conclusions: Thoracolumbar/lumbar AVBT surgery led to significant improvements in shoulder asymmetry and cervical lordosis of AIS patients in the early to early-mid postoperative period. However, compared with spinal fusion techniques, thoracolumbar/lumbar AVBT did not demonstrate superiority in functional scores or sagittal parameters. The mid- to long-term benefits of thoracolumbar/lumbar AVBT remain uncertain and require further investigation. Full article

Transnational higher education programs in engineering face persistent challenges in sustaining student motivation, engagement, and learning outcomes. Cultural norms, linguistic barriers, and traditional pedagogies often reinforce teacher-centred instruction, limiting active participation. This mixed-methods action research investigates how problem-based learning (PBL) supported by interactive handouts affects students’ motivation, engagement, and perceived learning outcomes in civil engineering programs, delivered in a Sino–UK university context. Drawing upon socio-cultural constructivism, Self-Determination Theory (SDT), and the multidimensional framework of student engagement, the study repositions motivation and engagement as central drivers of learning. Quantitative data from student surveys (N = 49) and qualitative responses from open-ended questions were analysed to identify patterns of perceived improvement and underlying mechanisms. Findings reveal that the scaffolded PBL and interactive tasks enhanced students’ intrinsic motivation, collaborative engagement, and self-reported understanding of key concepts. Students described the activities as “more interesting,” “interactive,” and “helpful for exam preparation.” In total, 92% agreed that the handouts improved their understanding of core concepts, while 78% of students reported being more motivated to participate in class, and 92% of students expressed that the handouts enhanced the learning environment. While self-reported perceptions limit causal claims, the findings contribute to a growing body of evidence advocating for learner-centred, motivationally informed pedagogies in transnational engineering education. Full article