Search Results (585)

Cold metal transfer (CMT) welding and metal inert gas (MIG) arc welding of a novel Al-Zn-Mg-Cu-Er-Zr alloy are systematically analyzed. The effect of the two welding processes on the morphology, microstructure, and mechanical properties of welded joints was investigated. The evolution of the microstructures and grain structures in the welded joints is studied using an optical microscope (OM), X-ray diffraction (XRD), and scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). The results show that both welding methods obtain well-formed full-penetration welds, and the width of the heat-affected zone (HAZ) of CMT welding is smaller than that of MIG welding. The two welded joints reveal coarse cellular grain structures with precipitates of η (MgZn₂), Al₃Er, and S (Al₆CuMg₄) secondary phases. The average grain size of the weld metal in the cold metal transfer welding (12.96 μm) joint is much finer than that of the metal inert gas arc welding joint (22.63 μm), with a higher proportion of high-angle grain boundaries (HAGBs). The hardness of cold metal transfer welding and metal inert gas arc welding weld zones is 103.9 HV and 92.6 HV, respectively, and the tensile strength of the joint is 334.0 MPa and 270.3 MPa, respectively. Full article

This study investigates the fabrication of a Cu-Mn-Al alloy coating on 27SiMn steel using Cold Metal Transfer (CMT) technology with an innovative Ar-B(OCH₃)₃ mixed shielding gas, focusing on the effect of the gas flow rate (5–20 L/min). The addition of B(OCH₃)₃ was found to significantly enhance process stability by improving molten pool wettability, resulting in a wider cladding layer (6.565 mm) and smaller wetting angles compared to pure Ar. Macro-morphology analysis identified 10 L/min as the optimal flow rate for achieving a uniform and defect-free coating, while deviations led to oxidation (at low flow) or spatter and turbulence (at high flow). Microstructural characterization revealed that the flow rate critically governs phase evolution, with the primary κI phase transforming from dendritic/granular to petal-like/rod-like morphologies. At higher flow rates (≥15 L/min), increased stirring promoted Fe dilution from the substrate, leading to the formation of Fe-rich intermetallic compounds and distinct spherical Fe phases. Consequently, the cladding layer obtained at 10 L/min exhibited balanced and superior properties, achieving a maximum shear strength of 303.22 MPa and optimal corrosion resistance with a minimum corrosion rate of 0.02935 mm/y. All shear fractures occurred within the cladding layer, demonstrating superior interfacial bonding strength and ductile fracture characteristics. This work provides a systematic guideline for optimizing shielding gas parameters in the CMT cladding of high-performance Cu-Mn-Al alloy coatings. Full article

Objectives: To evaluate the relationship between hyperreflective dots (HRDs) observed on spectral-domain optical coherence tomography (SD-OCT) and the outcomes following treatment with intravitreal ranibizumab or dexamethasone injections in patients with diabetic macular edema (DME). Methods: This retrospective study focused on individuals suffering from diabetic macular edema (DME) who underwent a sequence of three intravitreal ranibizumab injections. Based on treatment response, the eyes were categorized into two groups: responders and non-responders. The non-responder group subsequently received intravitreal dexamethasone (IVO) implants. Treatment results were evaluated by changes in BCVA, HRD number, and central macular thickness (CMT). Results: This research involved 112 eyes from 78 participants who had been diagnosed with DME. Seventy-three eyes (65%) were identified as ranibizumab responders and 39 eyes (35%) as ranibizumab non-responders. Of the 39 individuals who had suboptimal response to ranibizumab and subsequently received treatment with an intravitreal dexamethasone implant, 26 eyes (66.67%) exhibited a favorable response, while 13 eyes (33.33%) showed an insufficient response. IVR responders demonstrated significantly greater improvements in BCVA (0.54 ± 0.73 to 0.35 ± 0.40 logMAR vs. 0.52 ± 0.61 to 0.47 ± 0.38 logMAR) and CMT (456.53 ± 109.73 μm to 235.47 ± 49.13 μm vs. 468.99 ± 127.10 μm to 427.45 ± 52.91 μm) reduction. Baseline analysis revealed IVR non-responders had higher counts of both inner and outer retinal HRDs compared to responders (9.09 ± 3.38 vs. 7.07 ± 2.32 and 5.46 ± 2.03 vs. 4.27 ± 1.87, p < 0.05, respectively). Eyes with initially higher numbers of inner retinal HRDs, outer retinal HRDs, and subretinal HRDs demonstrated a significantly enhanced response to dexamethasone therapy (9.03 ± 3.18 vs. 7.55 ± 2.72, 6.55 ± 2.46 vs. 4.79 ± 1.88 and 0.27 ± 0.54 vs. 0.21 ± 0.47, p < 0.05, respectively). Conclusions: HRDs could potentially be used as a predictive biomarker to assess the effectiveness of anti-VEGF therapy in treating DME. Patients exhibiting a greater number of retinal HRDs tend to have less favorable reactions to anti-VEGF treatments but experience improved results with dexamethasone. Full article

Many individuals suffer from sleep disorders associated with chronic pain, neuroendocrine diseases, and primary sleep disorders. Although cervical manual therapy (CMT) is frequently presumed to enhance sleep quality in clinical settings, evidence regarding its effects on sleep remains inconclusive. We aimed to evaluate the therapeutic effect of CMT and clinical patterns, providing novel insights into its applicability for sleep disorders and further mechanism studies. Methods: A comprehensive literature survey was conducted by using 6 databases through February 2025, to identify randomized controlled trials (RCTs) assessing the effect of CMT on sleep quality as clinical outcome, regardless of primary diseases. Results: Among 1220 initial studies, a total of 10 RCTs involving 552 participants were included. All included RCTs assessed sleep quality using patient-reported outcome measures, while only one study utilized objective assessment via polysomnography. Among them, seven RCTs (70.0%) reported significant improvements in sleep quality that were not dependent on alleviating the primary diseases, with notable enhancements in subjective sleep depth and efficiency rather than sleep duration or latency. Sleep benefits were pronounced in primary sleep disorders, such as obstructive sleep apnea and bruxism, and in sleep disturbances secondary to other conditions, with limited effects in fibromyalgia (FM). Conclusions: With the dysregulated hypothalamic–pituitary–adrenal axis and aberrant serotonergic activity in FM, in this review, we formed a hypothesis and explored the potential effects of CMT on sleep-related serotonergic activity and HPA axis regulation. This scoping review underscores the need for further research to clarify the neuroendocrinological mechanisms underlying CMT’s role in sleep modulation and its potential applications in sleep-related disorders. Full article

Background: In the dynamic world of commercial aviation, the efficient management of ground handling (GH) operations in aircraft turnarounds is an increasingly complex challenge, often perceived as operational chaos. Methods: This paper introduces the “Critical Minute Theorem” (CMT), a novel framework that integrates mathematical architecture principles into the optimization of GH processes. CMT identifies singular temporal thresholds, $t_k^{\mathrm{*}}$ at which small local disturbances generate nonlinear, system-wide disruptions. Results: By formulating the turnaround as a set of algebraic dependencies and nonlinear differential relations, the case studies demonstrate that delays are not random but structurally determined. The practical contribution of this study lies in showing that early recognition and intervention at these critical minutes significantly reduces propagated delays. Three case analyses are presented: (i) a fueling delay initially causing 9 min of disruption, reduced to 3.7 min after applying CMT-based reordering; (ii) baggage mismatch scenarios where CMT-guided list restructuring eliminates systemic deadlock; and (iii) PRM assistance delays mitigated by up to 12–15 min through anticipatory task reorganization. Conclusions: These results highlight that CMT enables predictive, non-technological control in turnaround operations, repositioning the human analyst as an architect of time capable of restoring structure where the system tends to collapse. Full article

This study systematically investigates the effects of welding current on the macro-morphology, microstructure, mechanical properties, and corrosion resistance of Cu-Mn-Al alloy coatings deposited on 27SiMn steel substrates using Cold Metal Transfer (CMT) technology. The 27SiMn steel is widely applied in coal mining, geology, and engineering equipment due to its high strength and toughness, but its poor corrosion and wear resistance significantly limits service life. To address this issue, a Cu-Mn-Al alloy (high-manganese aluminum bronze) was selected as a cladding material because of its superior combination of mechanical strength, toughness, and excellent corrosion resistance in saline and marine environments. Compared with conventional cladding processes, CMT technology enables low-heat-input deposition, reduces dilution from the substrate, and promotes defect-free coating formation. To the best of our knowledge, this is the first report on the fabrication of Cu-Mn-Al coatings on 27SiMn steel using CMT, aiming to optimize process parameters and establish the relationship between welding current, phase evolution, and coating performance. The experimental results demonstrate that the cladding layer width increases progressively with welding current, whereas the layer height remains relatively stable at approximately 3 mm. At welding currents of 120 A and 150 A, the cladding layer primarily consists of α-Cu, κII, β-Cu₃Al, and α-Cu + κIII phases. At higher welding currents (180 A and 210 A), the α-Cu + κIII phase disappears, accompanied by the formation of petal-shaped κI phase. The peak shear strength (509.49 MPa) is achieved at 120 A, while the maximum average hardness (253 HV) is obtained at 150 A. The 120 A cladding layer demonstrates optimal corrosion resistance. These findings provide new insights into the application of CMT in fabricating Cu-Mn-Al protective coatings on steel and offer theoretical guidance for extending the service life of 27SiMn steel components in aggressive environments. Full article

Early-life exposure to organic chemicals (OCs) may influence childhood obesity and associated cardiometabolic risk. These conditions have been shown to disproportionately affect minority populations such as Mexican Americans (MAs). However, information on the impact of organic chemicals on cardiometabolic risk in MA children is limited. Therefore, we conducted a pilot study to assess the extent to which exposure to organic chemicals influences cardiometabolic traits (CMTs) in MA children. We recalled 25 children from a previous study and collected 25 primary teeth from them. Chemical analyses of the teeth were performed using established protocols. Target analytes included acetaminophen (APAP); 3,5,6-trichloro-2-pyridinol (TCPy), 2-isopropyl-6-methyl-4-pyrimidinol (IMPy), diethyl phosphate (DEP), N,N-diethyl-m-toluamide (DEET), tris(2-butoxyethyl) phosphate (TBOEP), monoethyl phthalate (MEP), mono-n-butyl phthalate (MnBP), monoisobutyl phthalate (MiBP), monobenzyl phthalate (MBzP), mono-2-ethylhexyl phthalate (MEHP), mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), and mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP). The organic chemicals most frequently detected in the teeth were APAP; the insect repellent DEET; plasticizers MnBP and MiBP; and the plasticizer-derived metabolite MEHP. These five analytes were included in association analyses with selected CMTs. After adjusting for covariate (age, sex, tooth-type) effects, we found significant (p < 0.05) positive correlations between MiBP and the following CMTs: fat mass, fasting insulin, and the homeostasis model of assessment-insulin resistance (HOMA-IR). Both MnBP and MEHP exhibited negative correlation with blood pressure measures and triglycerides, respectively. In addition, APAP showed a strong negative correlation with HDL-C (p = 0.009) and positive association with triglycerides (p < 0.10). These findings suggest a potential role for early-life exposures to organic chemicals in influencing cardiometabolic risk in MA children. Full article

Neurological disorders significantly affect ocular surface homeostasis, influencing parameters such as blink rate (BR), tear production, corneal nerve density, and sensitivity. This review summarizes recent findings on ocular surface alterations associated with neurological diseases, including Alzheimer’s disease (AD), Parkinson’s disease (PD), Guillain-Barré syndrome (GBS), trigeminal neuralgia (TN), multiple sclerosis (MS), and Charcot–Marie–Tooth disease (CMT). Notably, ocular manifestations such as reduced BR, decreased tear break-up time (TBUT), impaired tear secretion, and corneal nerve fiber loss are consistently reported. In AD, elevated tear amyloid-beta and tau proteins emerge as promising biomarkers for early disease detection. PD patients frequently experience dry eye symptoms attributed to reduced BR and tear film instability. GBS is linked to lagophthalmos and corneal nerve impairment, potentially leading to severe ocular surface damage. TN demonstrates bilateral ocular surface dysfunction despite unilateral neuropathic symptoms. MS is associated with significant ocular surface alterations, reflecting broader neuroinflammatory and autonomic disturbances. Similarly, CMT patients show reduced corneal sensitivity and tear production, underscoring the systemic nature of neurological impacts. Awareness of these ocular manifestations is essential for improving patient care and guiding future research into ocular biomarkers and targeted therapies. Full article

Laser- and energy-based device (EBD) treatments in aesthetic medicine pose substantial environmental challenges, including high energy consumption, carbon emissions, and disposable medical waste. Although sustainable healthcare has gained global attention, no competency framework currently exists to guide physicians in integrating environmental sustainability into aesthetic medicine. This study applied McClelland’s (1973) Competency Model Theory (CMT) to develop a sustainability-oriented competency model for physicians specializing in laser and EBD treatments. Using a mixed-methods design, competency-based interviews were conducted to identify the key tasks and sustainability-related competencies, followed by expert panel validation using content validity and Kendall’s coefficient of concordance. The final model consists of 33 competencies across six domains: sustainable operations, regulatory and ethical knowledge, physician patient communication, dermatological science, EBD techniques, and maintenance care. Experts rated most competencies as highly or very highly important and frequently used, and Kendall’s W confirmed significant consensus across domains. The model provides standardized competency benchmarks that can support future curriculum development, professional training, and sustainable healthcare governance. This study extends CMT into the field of environmental sustainability in medicine and offers a structured framework to reduce ecological footprints and promote low-carbon, socially accountable practices. Full article

In recent years, multi-modal 3D object detection algorithms have experienced significant development. However, current algorithms primarily focus on designing overall fusion strategies for multi-modal features, neglecting finer-grained representations, which leads to a decline in the detection accuracy of small objects. To address this issue, this paper proposes the Instance-aware Fine-grained feature Enhancement Cross Modal Transformer (IFE-CMT) model. We designed an Instance feature Enhancement Module (IE-Module), which can accurately extract object features from multi-modal data and use them to enhance overall features while avoiding view transformations and maintaining low computational overhead. Additionally, we design a new point cloud branch network that effectively expands the network’s receptive field, enhancing the model’s semantic expression capabilities while preserving texture details of the objects. Experimental results on the nuScenes dataset demonstrate that compared to the CMT model, our proposed IFE-CMT model improves mAP and NDS by 2.1% and 0.8% on the validation set, respectively. On the test set, it improves mAP and NDS by 1.9% and a 0.7%. Notably, for small object categories such as bicycles and motorcycles, the mAP improved by 6.6% and 3.7%, respectively, significantly enhancing the detection accuracy of small objects. Full article

Non-CG DNA methylation plays a critical role in regulating root development and stress responses in Arabidopsis thaliana under cadmium (Cd²⁺) exposure. We compared wild type (WT) plants with the ddc triple mutant (deficient in DRM1, DRM2, and CMT3) to assess how epigenetic modifications affect the root apical meristem (RAM) under 100 µM and 150 µM CdCl₂ treatments. Cd²⁺ exposure led to RAM disorganization, reduced cortical cell number, and quiescent center (QC) cell loss in WT roots, while ddc mutants maintained meristem integrity and exhibited QC cell expansion. Auxin signaling, assessed via pDR5::GFP, was disrupted in WT roots at high Cd²⁺ levels but remained stable in ddc mutants. Similarly, WT roots showed elevated reactive oxygen species accumulation under stress, whereas ddc mutants displayed a reduced oxidative response. These results suggest that non-CG DNA methylation suppresses key regulators of stem cell maintenance, hormonal balance, and redox homeostasis during heavy metal stress. Loss of this methylation in the ddc mutant confers enhanced resilience to Cd²⁺ toxicity, highlighting an epigenetic mechanism underlying root stress adaptation. Full article

Background/Objectives: We evaluated the clinical features and natural course of treatment-naïve non-exudative macular neovascularization (NE MNV) associated with age-related macular degeneration in Korean patients. Methods: This retrospective longitudinal study of 21 eyes of 21 patients with NE MNV involved a chart review of best corrected visual acuity (BCVA), optical coherence tomography (OCT), and OCT angiography parameters. Results: This study included 13 men (13/21, 61.9%) and 8 women (8/21, 38.1%), with a mean age of 71.5 ± 9.1 years. The average follow-up period was 15.1 ± 11.8 (range 6.0–49.6) months, and 14 eyes (66.7%) demonstrated exudative changes on OCT scans. The baseline BCVA was 0.15 ± 0.18 logMAR. The initial central macular thickness (CMT), subfoveal choroidal thickness, and the outer retinal layer thickness were 265.3 ± 37.1, 245.2 ± 95.2, and 86.6 ± 5.3 μm, respectively. Cox proportional hazards analysis revealed that older age (hazard ratio [HR]: 1.096, 95% confidence interval [CI]: 1.002–1.200; p = 0.045), larger baseline CMT (HR: 1.025, 95% CI: 1.002–1.049; p = 0.035), and larger baseline MNV (HR: 1.618, 95% CI: 1.035–2.529; p = 0.035) were significant risk factors for exudative changes. Conclusions: We observed the clinical features and natural course of NE MNV in Korean patients and identified that significant risk factors for exudative changes in NE MNV included old age, initially thick CMT, and larger MNV size at baseline. For eyes with NE MNV that have risk factors of exudative conversion, more frequent observation is recommended to ensure the appropriate management. Full article

Canine mammary tumors (CMTs) are among the most frequently diagnosed neoplasms in female dogs, with complex etiologies involving age, breed, body size, and reproductive status. This retrospective study analyzed 250 cases comprising 361 mammary tumors to evaluate demographic patterns, histopathological subtypes, and their topographical distribution. The majority of tumors (88.64%) were malignant, with complex carcinoma being the most common subtype (24%), followed by intraductal papillary carcinoma (14.95%). The mean age at diagnosis was 9.36 years, with 60.8% of cases occurring in dogs older than 8 years. Mixed-breed dogs were most frequently affected, followed by Bichon-type breeds and German Shepherds. Small-sized dogs (<10 kg) accounted for 43.5% of cases. Regarding the reproductive status, 35.6% of dogs were unspayed, while the remainder were either intact or had an undetermined status, reflecting regional spaying practices. A statistically significant association was identified between histological subtype and mammary gland location, revealing non-random, region-specific tumor distribution. Complex carcinomas were frequently located in the left canial abdominal mammary segment (L.A2), right canial abdominal mammary segment (R.A2), and left inguinal mammary segment (L.ING); mixed and tubular carcinomas were more prevalent in R.A2 and R.ING; and tubulopapillary carcinomas appeared predominantly in L.ING. While no significant overall association was found between tumor grade and gland location, grade III carcinomas showed a possible predilection for the left inguinal gland (L.INGH), indicating a regional tendency that warrants further investigation. These findings underscore the importance of anatomical factors in the development of CMTs and support the integration of gland-specific tumor patterns into diagnostic assessment and surgical decision-making. Full article

Our study explored the role of serum 25-hydroxyvitamin D [25(OH)D] levels as an indicator of response to intravitreal anti–vascular endothelial growth factor (anti-VEGF) therapy in patients with diabetic macular edema (DME), highlighting functional and anatomical outcomes linked to systemic biomarker profiles. In a cohort of treatment-naive diabetic patients, vitamin D status was correlated with post-treatment changes in central macular thickness (CMT) and best-corrected visual acuity (BCVA), illustrating layered therapeutic responses among deficient, insufficient, and sufficient vitamin D groups. Functional gains, measured as improvements in decimal BCVA, and anatomical improvements, defined by CMT reduction via spectral-domain optical coherence tomography (SD-OCT), were primarily detected in patients with sufficient vitamin D levels. Remarkably, patients with serum 25(OH)D ≥ 30 ng/mL revealed complete dual-response rates, while those in the deficient group manifested partial therapeutic efficacy, supporting the immunoangiogenic modulatory role of vitamin D. Statistical associations exposed a tight linear connection between baseline and final visual acuity and a pronounced inverse relationship between CMT and final vision, suggesting that vitamin D may play a role in treatment-mediated structural recovery. These results may imply that low vitamin D levels lead to subclinical endothelial dysfunction and impaired retinal barrier repair, possibly through dysregulated anti–vascular endothelial growth factor (anti-VEGF) signaling, chronic inflammation, and oxidative stress. Our findings underscore the need for and importance of further research of vitamin D status as an adjunctive biomarker in the clinical approach of personalized DME and validates the potential of circulating vitamin D evaluation in therapeutic classification and predictive eye care. Full article

This study investigates the microstructure evolution and mechanical properties of DSS2209 duplex stainless steel fabricated via cold metal transfer wire arc additive manufacturing (CMT-WAAM). The as-deposited thin-wall components exhibit significant microstructural heterogeneity along the build height due to thermal history variations. Optical microscopy, SEM-EDS, and EBSD analyses reveal distinct phase distributions: the bottom region features elongated blocky austenite with Widmanstätten austenite (WA) due to rapid substrate-induced cooling; the middle region shows equiaxed blocky austenite with reduced grain boundary austenite (GBA) and WA, attributed to interlayer thermal cycling promoting recrystallization and grain refinement (average austenite grain size: 4.16 μm); and the top region displays coarse blocky austenite from slower cooling. Secondary austenite (γ₂) forms in interlayer remelted zones with Cr depletion, impacting pitting resistance. Mechanical testing demonstrates anisotropy; horizontal specimens exhibit higher strength (UTS: 610 MPa, YS: 408 MPa) due to layer-uniform microstructures, while vertical specimens show greater ductility (elongation) facilitated by columnar grains aligned with the build direction. Hardness ranges uniformly between 225–239 HV. The study correlates process-induced thermal gradients (e.g., cooling rates, interlayer cycling) with microstructural features (recrystallization fraction, grain size, phase morphology) and performance, providing insights for optimizing WAAM of large-scale duplex stainless steel components like marine propellers. Full article