Search Results (202)

To address the prominent fatigue failure risk of planetary gears in power-split hybrid buses and the lack of quantitative damage analysis across various operating modes in existing studies, this paper focuses on the front planetary gear set of a power-split hybrid bus. Based on a full-vehicle co-simulation model, loads under full operating conditions are decomposed into 11 operating modes, mode-switching loads are analyzed and extracted, and mode-decomposed and mode-switching fatigue loading spectra are compiled. Fatigue simulation is then conducted using Miner’s linear damage accumulation rule. Results show that the sun gear directly coupled to motor is the system’s most fatigue-susceptible component, exhibiting significant asymmetric unilateral tooth flank damage. The hybrid electric vehicle (HEV) mode contributes approximately 88% of total damage to the sun gear’s right flank, dominating system fatigue damage. Transient mode-switching conditions account for approximately 60% of total damage to the sun gear’s left flank, serving as the core damage source. Compared with the traditional full-condition merging method, the proposed mode-decomposed method improves the conservatism of life prediction. This work provides methodological support for refined strength design and targeted optimization of power-split hybrid transmission systems. Full article

Avoiding contrails is one of the recent trends in ATM. Aviation contrails are considered a significant non-CO₂ environmental factor worth avoiding even with a CO₂ increase (lower-level cruise or horizontal avoidance, both burning more fuel). This paper is a study of the global impact of aviation on global warming considering contrails and CO₂ trade-offs. In the literature, there are two concepts on why contrails are detrimental to the environment: (i) Daytime persistent contrails have a positive effect by reflecting the Sun’s rays back, whereas the contrails persisting into nighttime need to be avoided because they block the cooling of the planet by radiation—the overall impact is negative; (ii) too much humidity is injected into the tropopause by aircraft regardless of the type of contrails, persistent or not, and even by the flights without contrails. In hypothesis (ii), contrail avoidance is not the issue, since humidity is generated by the turbine engines regardless of the visibility of the water molecules (ice crystals or water droplets). Regarding hypothesis (i), the study analysed the Earth’s reflections contributing to albedo and the Earth’s emissions at the top of the atmosphere in infrared (day and night) over 25 years (2000–2025) from CERES data and found correlations with the two pandemic years, when the number of flights was significantly reduced, to understand the real environmental impact of aviation. The conclusion is that most of the time, contrails increase the Earth’s albedo, having a positive environmental impact. The damage to the environment comes mostly from 2% of flights, mainly over Europe, and the paper puts forward some practical proposals to regulate these flights, instead of complex contrail avoidance applied at the ATM level for all flights. Full article

Light availability is a key environmental factor influencing plant functional traits and ecological strategies. To investigate how natural populations of Iris pumila respond to contrasting irradiance, we conducted an in situ reciprocal transplant experiment using clonal genotypes from two natural populations, each originating from an open dune and a shaded forest habitat. Leaves collected from each of the replanted and transplanted genotypes were analyzed for structural (specific leaf area—SLA, leaf dry matter content—LDMC), physiological (specific leaf water content—SLWC, photosynthetic pigments) and biochemical (peroxidase—POD, glutathione reductase—GR, phenolics and anthocyanins) traits. Shade-grown individuals developed thinner leaves with higher SLA and chlorophyll content, enhancing light-harvesting efficiency, whereas sun-exposed plants exhibited greater LDMC, increased POD and GR activities and higher anthocyanin levels—traits consistent with enhanced photoprotection under high irradiance. All genotypes exhibited pronounced plasticity to light intensity, with habitat exerting a stronger influence on trait expression than population origin. To evaluate oxidative balance, we proposed the ODAC index (Oxidative Damage to Antioxidant Capacity), which integrates lipid peroxidation with antioxidant capacity. ODAC values revealed consistent population-level differences, with higher values in Dune genotypes across habitats, indicating a constitutively elevated oxidative load relative to antioxidant protection and suggesting differentiation in redox regulation between populations. Overall, leaf trait variation in I. pumila appears to be primarily driven by plastic responses to light conditions, while differentiation in oxidative physiology contributes to functional divergence between populations. Full article

Pomegranate (Punica granatum L.) is a major fruit crop in tropical and subtropical regions, but changing climatic conditions—especially rising temperatures and intense solar radiation—are increasing physiological disorders. Sunburn, a key heat- and light-induced disorder, causes peel discoloration and tissue damage. This results in significant yield loss and reduced fruit quality. The objective of this study was to characterize sunburn-induced anatomical changes in the widely grown, highly sensitive Hicaznar cultivar in Türkiye, and to identify the optimal phenological stage for the application of sunburn-preventive practices. For this purpose, pomegranate fruit peels were fixed in FAA (Formalin–Acetic Acid–Alcohol) solution, embedded in paraffin blocks, and sectioned at a thickness of 5–7 µm. The sections were stained using the hematoxylin–eosin method and examined under a light microscope. The images captured with a digital camera wereanalyzed and revealed that sunburn damage in the pomegranate peel first appears in the cuticle layer, followed by disruption and fragmentation of the cutaneous and epidermal layers beneath it, and ultimately leads to damage of the parenchyma cells. Furthermore, Light microscopy showed that before visible discoloration, cells near the epidermis undergo phenolic accumulation, cell-wall thickening, and lignification, which are early indicators of sunburn. These microscopic changes provide early diagnostic features for detecting sunburn damage before external symptoms manifest. The study concluded that anatomical changes begin before the visible symptoms of sunburn appear on the fruit, and the most appropriate timing for applying preventive measures against sunburn has been identified. Light microscopy showed that before visible discoloration, cells near the epidermis undergo phenolic accumulation, cell-wall thickening, and lignification, which are early indicators of sunburn. Full article

PRAME (Preferentially Expressed Antigen in Melanoma) is increasingly used as an immunohistochemical marker in the evaluation of melanocytic lesions; however, its expression in benign melanocytic proliferations remains incompletely characterized. This study investigated PRAME expression in melanoacanthomas, with particular emphasis on its relationship with ultraviolet exposure and chronic solar damage. A consecutive series of melanoacanthomas was retrospectively analyzed. Melanocytes were identified and quantified using SOX10 immunohistochemistry, while PRAME-positive melanocytes were counted and graded semiquantitatively according to nuclear staining intensity. PRAME expression was correlated with lesion site (photoexposed versus non-photoexposed skin) and with the degree of solar elastosis. Eighty-four cases were evaluated, of which 25 (29.8%) showed at least focal PRAME positivity in melanocytes. Overall melanocytic density assessed by SOX10 did not differ significantly between photoexposed and non-photoexposed lesions. Similarly, stratification based on total PRAME-positive melanocyte counts, irrespective of staining intensity, revealed no significant association with photoexposure. In contrast, analysis restricted to melanocytes with strong nuclear PRAME expression demonstrated a significant enrichment in photoexposed lesions compared with non-photoexposed sites (p < 0.01). Moreover, high-intensity PRAME expression showed a positive association with increasing grades of solar elastosis. These findings indicate that strong PRAME expression in melanoacanthoma could be associated with chronic sun damage and may reflect non-specific, ultraviolet-related modulation rather than malignant transformation, underscoring the importance of contextual interpretation of PRAME immunohistochemistry in diagnostic practice. Full article

Nuclear mechanics and mechanotransduction are involved in the migration and invasion process, such as those in which the cells need to deform themselves to pass through constrictions. Specifically, properties like nuclear softness, viscoelasticity, plasticity (like nuclear pore complexes) and deformability are critical in cancer and its malignant progression. The nucleus represents a physical barrier for the migration and invasion in dense 3D extracellular matrix (ECM) scaffolds. Therefore, the deformability of the nucleus seems to determine the migration limit in circumstances where the enzymatic remodeling of the surroundings is impaired. There are still significant knowledge gaps regarding effects of nuclear deformation during cancer dissemination. It seems that nuclear deformation can alter gene transcription, induce alternative splicing processes, impact nuclear envelope rupture, nuclear pore complex dilatation, damage the DNA, and increase the genomic instability. These mechanically induced alterations can in turn impact the migratory behavior of the cancer cells. The stiffness of the nucleus relies on the condensation of chromatin, and the nuclear lamina, which consists of a network of intermediate filaments underneath the nuclear envelope. All of this is discussed in the review and it is argued that nuclear deformability is universally found in various cancer types. Another focus is placed on the nuclear envelope proteins like emerin, and the SUN-KASH complex and how they contribute to the Linker of Nucleoskeleton and Cytoskeleton (LINC) complex, which consequently couples the nucleus and the cytoskeleton. It is argued that this connection is crucial for force transmission, which governs nuclear stiffness dynamically, depending on the force applied. In this review, recent findings are described that couple ECM-induced nuclear mechanosensing and mechanotransduction with the migration and invasion of cancer cells. Moreover, it is suspected that changes in the mechanosensory characteristics of the cell nucleus could play a pivotal part in the malignancy of cancer cells and the heterogeneity of tumors. Finally, it is discussed what impact the individual elements of the nucleus offer to mechanically alter cellular migration and invasion in cancer and its malignant progression. Full article

Background/Objectives: Imatinib mesylate (IM) is the first-line therapy for gastrointestinal stromal tumor (GIST). Emerging evidence suggests that genes involved in m6A modification, autophagy, and DNA damage repair pathways might contribute to IM secondary resistance and result in substantial inter-patient variability in treatment outcomes. However, influence of the genetic variations in these genes on IM-treated GIST remains unclear. Methods: A total of 172 GIST patients treated with IM in Sun Yat-sen University Cancer Center from 2014 to 2018 were enrolled. A 6-month landmark analysis was applied to specifically investigate secondary resistance, restricting the cohort to patients alive and progression-free at 6 months. Tag single-nucleotide polymorphisms (SNPs) in 54 evidence-based candidate genes involved in m6A modification, autophagy, and DNA damage repair pathways were selected and genotyped. Associations between SNPs and progression-free survival (PFS) were assessed using univariate Cox regression and Kaplan–Meier analyses with time zero reset to the 6-month landmark. Identified SNPs were further analyzed in multivariable Cox models adjusted for demographic and clinical factors. Results: During a median follow-up of 53.62 months (range, 7.60–129.77) as of October 2023, 39 progression events occurred. Univariate analyses identified 12 SNPs located in 9 genes associated with PFS. After adjustment for demographic and clinical covariates, 10 SNPs remained associated with PFS. Of these, seven variants were located in m6A pathway genes (ALKBH5, METTL3, YTHDC2, and ZC3H13), four of which were associated with shorter PFS (e.g., YTHDC2 rs1833678 T > C, HR = 2.87, 95% CI: 1.18–7.03, p = 0.021) and three with longer PFS (e.g., METTL3 rs1263793 A > G, HR = 0.40, 95% CI: 0.20–0.83, p = 0.014) of progression. A cumulative genetic risk score based on the identified m6A SNPs was associated with PFS (p < 0.001). Additionally, one SNP in autophagy and two in DNA damage repair pathways also remained associated with PFS after adjustment. Conclusions: Genetic polymorphisms in the m6A modification genes, along with variants in autophagy and DNA damage repair pathways, were associated with PFS in IM-treated patients who had achieved initial disease control. The cumulative risk score based on m6A pathway variants showed a strong association with PFS. These findings provide preliminary, hypothesis-generating evidence that genetic variations may contribute to inter-patient variability in outcomes and warrant further investigation as potential biomarkers in IM-treated GIST. Full article

Ultraviolet (UV) radiation induces DNA damage and oxidative stress in melanocytes, shaping pigmentation phenotypes and elevating photocarcinogenesis risk. Human models that capture donor-linked genetic determinants of UV sensitivity remain limited. Here, we establish a genotype-informed UV response model using induced pluripotent stem cell (iPSC)-derived melanocytes from donors carrying defined MC1R variants. Differentiated cells recapitulated melanocytic morphology, marker expression, and pigmentation consistent with donor sun-sensitivity traits. Following narrowband UVB exposure, melanocyte lines with higher UV sensitivity showed reduced survival, prolonged checkpoint activation, and CPD-associated DNA damage signaling dynamics. Mechanistic analysis suggests that the interferon-regulated GTPase MX2 is associated with amplification of UV-induced p53 and p38 activation while promoting apoptosis independently of AKT. These findings support MX2 as a physiological enhancer of DNA damage signaling in normal melanocytes, distinct from its interferon-mediated role in melanoma. Our study provides a human-relevant platform linking pigmentation genotype to UV resilience and supports iPSC-derived systems as new approach methodologies (NAMs) for mechanistic and translational phototoxicology. Full article

Mechanical harvesting damage is a critical factor constraining potato quality and storage performance. Field curing is a commonly employed pre-treatment prior to mechanical picking of potatoes, which promotes skin suberization and reduces mechanical damage; however, the determination of optimal curing duration lacks a theoretical basis. This study investigated ‘Xisen No. 6’ potatoes at harvest maturity. Curing was performed by field sun-drying (open-air exposure) immediately after mechanical excavation, with five duration gradients (0, 1, 2, 3, and 4 h) established under the recorded meteorological conditions. Twenty-two physical–mechanical and damage parameters were measured, and principal component analysis (PCA) was employed for comprehensive evaluation. The results demonstrated that curing induced a transformation of tubers from “soft-elastic bodies” to “hard-brittle bodies”. This study first revealed the contradictory evolution pattern between skin abrasion damage and tissue impact damage, which exhibited a strong negative correlation (r = −0.89, p < 0.01). PCA indicated that a 3 h curing duration could effectively balance the control of both damage types. These findings provide a quantitative solution to the dilemma of reducing skin damage while controlling impact damage during mechanical potato harvesting, offering significant guidance for optimizing harvesting process parameters and reducing postharvest losses. Full article

In mitotic cell division, cytokinesis is followed by abscission, the final separation of the cytoplasmic canal, to release the two genetically identical daughter cells; however, sometimes chromatin bridges connecting the daughter nuclei appear. Preserving intact chromatin bridges is crucial because their breakage can cause DNA damage, aneuploidy, and cancer predisposition. For this purpose, cells use two main mechanisms: first, they activate the abscission checkpoint, a mechanism that delays the final cut of the cytoplasmic canal to prevent chromatin bridge breakage and secondly, they form accumulations of actin (“actin patches”) at the base of the intercellular canal to stabilize chromatin bridges. Here, we highlight new findings from our laboratory on how human cells “sense” chromatin bridges and remodel the actin cytoskeleton to generate actin patches in cytokinesis. More specifically, we discuss findings showing that the nuclear membrane Sun1/2-Nesprin-2-LINC (linker of nucleoskeleton and cytoskeleton) complex promotes the generation of mechanical tension on daughter nuclei with chromatin bridges. This tension leads to accumulation of Sun1/2 and Nesprin-2, and cytoplasmic accumulation of PDZ RhoGEF (PDZ domain-containing Rho guanine nucleotide exchange factor) at the base of the intercellular canal. In turn, PDZ RhoGEF activates downstream RhoA-ROCK-LIMK-Cofilin and RhoA-mDia1 signaling pathways to promote actin patches and prevent chromatin bridge breakage in cytokinesis. Full article

Coffee-derived materials from diverse botanical sources (beans, leaves, fruit and spent grounds) contain bioactive polyphenolic compounds, alkaloids, and diterpenes with potential dermatological applications. This review critically evaluates evidence quality across study designs. In vitro studies demonstrate antioxidant, anti-aging, anti-inflammatory, photoprotective, wound-healing, and antimicrobial activities. Animal models show photoprotection and wound-healing effects. These studies highlight the multifunctional dermatological value of coffee-derived materials as ingredients for cosmetic and therapeutic formulations aimed at combating skin aging, inflammation, and barrier dysfunction. Limited human trials (typically small sample sizes and short duration) report modest improvements in skin hydration, elasticity, barrier function, and reductions in erythema, transepidermal water loss, and ultraviolet-induced damage, though methodological limitations constrain interpretation. Observational epidemiological studies report inverse associations between coffee consumption and melanoma/basal cell carcinoma risk, but residual confounding by sun exposure, lifestyle factors, and genetic susceptibility precludes causal inference. Critical translational barriers include insufficient pharmacokinetic characterization, inadequate extract standardization across sources and processing methods, formulation challenges, bioavailability uncertainties, and limited independent validation. While preclinical evidence supports diverse biological activities and suggests multifunctional potential for cosmetic and therapeutic applications, current evidence remains insufficient to recommend coffee-derived products as a primary evidence-based dermatological intervention. Overall, large-scale, independent clinical trials with adequate duration and clinically meaningful endpoints are essential for translating laboratory findings into validated clinical applications. Full article

The cacao tree is naturally adapted to shade; however, cultivation in full-sun systems is becoming increasingly common. However, high light intensity can damage the photosynthetic apparatus, making the choice of genotype fundamental to the success of the crop. Thus, in the north of the state of Espírito Santo, municipality of Linhares, the physiological and biochemical responses of the cacao genotypes PS1319, CEPEC 2002, and PH16 were evaluated in agroforestry, cabruca, and full sun cultivation systems during the months of April to October. To this end, chlorophyll a fluorescence, photosynthetic pigments, and carbohydrates were evaluated using a completely randomized split-plot experimental design. Across agroforestry, cabruca (a traditional Brazilian shaded system), and full-sun systems, the cacao genotypes PH16, PS1319, and CEPEC 2002 did not show limitations in photosynthetic performance, as evidenced by the stable values of PI abs and PI total throughout the evaluation period. The highest quantity of photosynthetic pigments was found in the genotypes CEPEC 2002, PH16, and PS1319 in full sun cultivation, in the genotypes PH16 and PS1319 in the agroforestry system, and in the genotype CEPEC 2002 in the cabruca system. The genotypes PH16 and PS1319 obtained higher levels of glucose, sucrose, and fructose, both in shaded environments (agroforestry and cabruca systems) and in full sun. Therefore, due to their greater stability and adaptability, we recommend the PH16 and PS1319 genotypes for cultivation in agroforestry and full-sun systems, and the CEPEC 2002, PH16, and PS1319 genotypes for the cabruca cultivation system. Full article

Lentigo maligna (LM) is a melanoma in situ with high cumulative sun damage. Histological evaluation of resection margins is difficult and time-consuming. Melanocyte density (MD) is a suitable, quantifiable, and reproducible diagnostic criterion. In this retrospective single-centre study, we investigated whether an artificial intelligence (AI) tool can support the assessment of LM. Training and evaluation were based on MD in Sox-10-stained digitalised slides. In total, 86 whole slide images (WSIs) from LM patients were annotated and used as a training set. The test set consisted of 177 slides. The tool was trained to detect the epidermis, measure its length, and determine the MD. A cut-off of ≥30 melanocytes per 0.5 mm of epidermis length was defined as positive. Our AI model automatically recognises the epidermis and measures the MD. The model was trained on nuclear immunohistochemical signals and can also be applied to other nuclear stains, such as PRAME or MITF. The WSI is automatically visualised by a three-colour heat map with a subdivision into low, borderline, and high melanocyte density. The cut-offs can be adjusted individually. Compared to manually counted ground truth MD, the AI model achieved high sensitivity (87.84%), specificity (72.82%), and accuracy (79.10%), and an area under the curve (AUC) of 0.818 in the test set. This automated tool can assist (dermato) pathologists by providing a quick overview of the WSI at first glance and making the time-consuming assessment of resection margins more efficient and more reproducible. The AI model can provide significant benefits in the daily routine workflow. Full article

Bolter miners have been widely used in coal mining or excavation industries. Its efficiency is closely related to the performance of its cutting reducer, which is literally determined by the thermal behavior of the planetary gear set. Thus, this study conducts experimental investigation on the thermal behavior of a cutting reducer (produced by Zhengzhou Machinery Research Institute Transmission Technology Co., Ltd., rated input power 170 kW, transmission ratio 3.06), where the results show the high temperature rise around the intermediate shaft for unloaded condition and significant influence of the torque for loaded conditions. Then, the Finite Element Method (FEM) is used to analyze the temperature field and thermal–structural coupling of the planetary gear set. The thermal stress and deformation increase by 11.5% and 38.4%, respectively, indicating high risk of gear damage. Moreover, the load spectrum imitating the actual industrial condition is added to the KISSsoft to evaluate the reliability and contact of the planetary gear set. The findings including low safety factors of the sun gear tooth surface and planetary gear root, slipping during the sun gear and planetary gear meshing, and uneven contact fluctuations can benefit planetary gear set optimization. Full article

Background: Photoaging results from cumulative ultraviolet-induced damage, mainly affecting sun-exposed areas such as the face, neck, and forearms. It manifests with textural roughness, irregular pigmentation, and wrinkles, reflecting structural degeneration across cutaneous layers. Objectives: This retrospective, uncontrolled, pilot study evaluated the efficacy of a biorejuvenating intradermal treatment combining free hyaluronic acid (HA) and glycerol in improving skin quality assessed by VISIA^® CR. Secondary objectives included morphological and structural evaluation with PRIMOS 3D and LC-OCT, and exploratory clustering of post-treatment topography. Methods: Seventeen Caucasian women (45–67 years; mean 54, Fitzpatrick I–III) received HA-glycerol (CROMA Revitalis) via three-session picotage (n = 10) or two-session four-point injection (n = 7). VISIA^® CR5 (spots, wrinkles, texture, pores, UV spots, porphyrins), PRIMOS 3D (roughness, volumetric parameters), and LC-OCT (stratum corneum and epidermal thickness, DEJ undulation) were analyzed. Results: VISIA^® CR5 showed significant reductions in visible spots and porphyrins, with trends toward improvement in wrinkles and UV spots. PRIMOS 3D demonstrated qualitative improvement in most patients, and LC-OCT documented a significant increase in stratum corneum thickness with positive remodeling trends. Conclusions: This retrospective uncontrolled pilot study suggests that HA–glycerol intradermal biorejuvenation may improve multiple markers of photoaging, although conclusions are limited by sample size and short follow-up. Full article