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Characterization and application of pulsed DC sputter deposited hydrogenated amorphous carbon (a-C:H) for durable multilayer infrared optical coatings on chalcogenide glasses
No full textDurable optical coatings using pulsed DC sputtered hydrogenated amorphous carbon (a-C:H) were deposited on chalcogenide glasses for the longwave infrared (LWIR—8–12 µm) spectral band. Carbon layers were deposited with a novel, to the best of our knowledge, multilayer, consisting of a bulk layer of high hydrogen content and a thin capping layer of low hydrogen content. This produces a layer that combines low stress with high hardness and durability and good adhesion on chalcogenide glasses. Two- and four-layer a-C:H/germanium multilayer anti-reflection coatings are demonstrated with average LWIR transmittances (reflectance) of 92.4% (2.2%) and 94.4% (1.1%), respectively. Using the novel layered hydrogenation approach during carbon deposition achieved optimal optical performance, coating stress, and hardness resulting in durable LWIR anti-reflection coatings that pass both MIL-C-48497A durability requirements and MIL-C-675C (para 4.5.9) salt spray. In addition, the antireflection coatings pass 10,000 wipes of the TS1888 para 5.4.3 sand slurry wiper test. The paper also describes stress, hardness, Young’s modulus, Raman, and electron paramagnetic resonance characterization of the a-C:H material, their relevance to optimizing optical and durability performance and variation with hydrogen content
Anhydrous lithic clasts in four CM2 carbonaceous chondrites derived from a thermally metamorphosed planetesimal with CM and CY affinities
No full textThe CM2 meteorites Grove Mountains (GRV) 021536, Murchison, and Shidian, contain anhydrous lithic clasts that have been interpreted as fragments of a planetesimal linked to CM or CV group carbonaceous chondrites. Here we describe 57 lithic clasts in Cold Bokkeveld (CM2) that are strikingly similar to those in the other three CMs in their petrography, mineralogy, and chemical and isotopic compositions. The Cold Bokkeveld clasts are dominated by equilibrated olivine, with subordinate plagioclase feldspar (andesine), clinopyroxene (diopside), nepheline, a spinel-group oxide (ferrian chromite), pentlandite, pyrrhotite, troilite and merrillite. Their bulk chemical composition is chondritic, and olivine oxygen isotope values span a wide range, from δ18O 3.6 ‰ Δ17O −3.9 ‰ to δ18O 20.3 ‰ Δ17O 1.1 ‰. Two clusters of clasts can potentially be distinguished from the chemical composition of their olivine: Fa38 and Fa41. The Fa38 cluster includes most of Cold Bokkeveld’s clasts and is close in chemical composition to those described from GRV 021526 and Murchison. The Fa41 cluster is represented by the largest Cold Bokkeveld clast, and its olivine is compositionally comparable to that in Shidian. Anhydrous lithic clasts that occur in all four of the CM meteorites are likely to have been derived from a large planetesimal with CM and CY affinities that had undergone thermal metamorphism and metasomatism. The CV3 breccias Mokoia and Yamato 86009 contain anhydrous lithic clasts that are close in mineralogy and oxygen isotopic composition to those in the four CMs and so are likely to have been sourced from the same carbonaceous planetesimal or one with a similar geological history. The oxygen isotopic compositions of olivine in clasts from GRV 021536, Murchison, Shidian, Cold Bokkeveld, Mokoia and Yamato 86009 plot on a shared trendline in 3-oxygen isotope space that connects the CV-CK-CO, CM, and CY fields thus suggesting genetic or evolutionary links between the five carbonaceous chondrite groups. The occurrence of these distinctive clasts in four CM2 meteorites could indicate that their parent body was the same rubble pile asteroid that had been built from aqueously altered and thermally metamorphosed lithologies
MicroRNAs as neuro-prognostic biomarkers after cardiac arrest: a systematic review
No full textCardiac arrest (CA) remains a leading cause of global mortality, largely due to hypoxic–ischaemic brain injury sustained during periods of absent cardiac output. MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression and have demonstrated diagnostic and prognostic potential in neurological and cardiovascular disease. This review assessed the value of miRNAs for predicting 6-month neurological outcomes following CA and return of spontaneous circulation (ROSC). Following PRISMA guidelines, PubMed and Cochrane Library searches identified ten clinical studies, comprising four biomarker studies and six post-hoc biomarker analyses from a large randomized controlled trial (RCT). Data on miRNA expression, patient characteristics, predictive accuracy (area under the receiver operating characteristic curve, AUC), and associations with outcome were extracted. Eleven miRNAs were differentially expressed within 72 h of ROSC; only miR-124-3p (up-regulated at 6 h) was replicated across studies. Eight studies contributed fifteen AUC values ranging from 0.62 to 0.89. Strong predictors included miR-6511b-5p (6 h, AUC = 0.85), miR-191-5p (48 h, AUC = 0.89), and miR-124 (48 h, AUC = 0.89). Four studies report associations between altered miRNA expression and unfavourable neurological outcomes, whilst one identified miR-122-5p as a positive prognostic biomarker. To conclude, miRNAs demonstrate distinct expression profiles following CA and ROSC, with several showing clinically useful prediction accuracy for 6-month neurological outcomes. Larger, unbiased studies using standardized methodologies are required to validate these findings and clarify confounding factors. Despite the current evidence limitations, this data supports further investigation of circulating miRNAs as neuro-prognostic biomarkers after cardiac arrest
A roll of the dice: pathogen–host interaction and the evolution of disease susceptibility
No full textThe probability that a disease will manifest is highly variable. Susceptibility to disease is influenced by genetic background, environment and lifestyle choices. In this review, we put forward the premise that evolution of disease susceptibility may be partially influenced by the interaction of divergent pathogen DNA-binding proteins with variable binding sites in the host genome. The hypothesis put forward is derived from recent data obtained from work on the protozoan parasite, Theileria annulata, together with related evidence from viral and bacterial pathogens that have been postulated to modulate host epigenome architecture. The pathogen proteins highlighted have the potential to mimic functions of mammalian epigenome organisers linked to a range of disease syndromes. It is feasible, therefore, that the evolutionary relationship between pathogen and host impacts susceptibility to a range of conditions, such as autoimmune disorders and cancer, which are not directly linked to pathogen infection
Skin cancer in inflammatory arthritis: should we advise screening?
No full textInflammatory arthritis refers to a group of related clinical entities marked mainly by inflammation of the joints, the spine, or both. Rheumatoid arthritis and spondyloarthritis (which includes psoriatic arthritis and axial spondyloarthritis) are the most common forms of inflammatory arthritis. As more studies are conducted, there are accumulating data suggesting the elevated risk of skin cancer, including both melanoma and non-melanoma skin cancer, in inflammatory arthritis compared with the general population. In this context, the question of whether screening for skin cancer should be recommended in individuals with inflammatory arthritis is more relevant than ever. In this Review, we discuss the current knowledge on the risk and possible associations of melanoma and non-melanoma skin cancer in inflammatory arthritis with the aim of raising awareness within the rheumatology community about the risk of skin cancer, screening, and guidance
Hybrid ResNet–Vision Transformer ensemble for early glaucoma detection from fundus images
Get PDFGlaucoma is a silent and progressive eye disease that can cause irreversible vision loss if left undiagnosed. Early detection and screening are therefore critical, particularly in underserved regions with limited ophthalmologic resources. This paper presents a deep learning based hybrid ensemble framework for early glaucoma detection from retinal fundus images. The proposed model integrates ResNet50 and Vision Transformer (ViT) architectures, enabling one to capture local spatial features and the other to learn global contextual representations. Preprocessing involves extracting the green channel and applying contrast-limited adaptive histogram equalization (CLAHE) to enhance retinal vessel visibility and texture detail. To improve generalization and mitigate class imbalance, data augmentation is applied before model training. The ensemble fuses softmax outputs from both models to produce the final classification. Experiments conducted on the standardized SMDG-19 dataset comprising 17,242 labeled fundus images demonstrate that the ensemble achieves 99.8% accuracy, F1-score = 1.0, and MCC = 0.994, confirming strong robustness to contrast variations, noise, and illumination changes
Reversible X‐ray memory imaging for cadmium‐based perovskites: deep trap‐driven radioluminescence enhancement
No full textX‐ray imaging has attracted significant attention for information encryption and anti‐counterfeiting. However, ensuring information security under multi‐level encryption scenarios remains challenges. Herein, we have developed a reversible X‐ray memory imaging technique for CsCdCl 3 :Pb perovskite, which integrates blue emission, persistent luminescence, and photochromic behavior into four stimulus response modes, enabling the multi‐level information encryption. Notably, CsCdCl 3 :Pb exhibits photochromic deepening, accompanied by a two‐fold enhancement in radioluminescence (RL) intensity with increasing X‐ray irradiation time. This enhancement originates from the formation of a new deep trap (0.79 eV) that facilitates energy transfer from the color centers to the Pb 2+ emission centers. Importantly, X‐ray memory imaging is attributed to the differences in RL enhancement between extending X‐ray irradiation time and turning on the X‐ray tube after removing capsule, which is demonstrated by cycling tests and stability characterizations under different dose rates. As a result, the RL enhancement and X‐ray memory imaging share common advantages: reversibility, fast response (5 s), rapid erasure capability (450 nm, 10–20 s), fatigue resistance (more than 100 cycles), and long‐term stability (more than half a year). This work presents an effective strategy for designing multi‐mode stimulus response perovskite materials and opens a new avenue for advanced multi‐level information security
Lactate dehydrogenase and outcomes in patients with HF and reduced ejection fraction
Get PDFBackground:
Lactate dehydrogenase (LDH) is a cytoplasmic enzyme found in most cells. Increased LDH levels are a nonspecific measure of cellular injury and may be prognostically important in heart failure (HF).
Objectives:
This study aims to assess the relationship between LDH and clinical characteristics and outcomes in heart failure with reduced ejection fraction (HFrEF).
Methods:
Using data from GALACTIC-HF, a phase 3, randomized, placebo-controlled trial evaluating the efficacy and safety of omecamtiv mecarbil (OM) in patients with HFrEF, the relationship between LDH and clinical outcomes was analyzed. The incremental value of LDH added to a validated prognostic model (PREDICT-HF) was also calculated using Harrell’s C statistic, integrated discrimination index (IDI), and net reclassification index (NRI).
Results:
In GALACTIC-HF, baseline LDH data were available for 8,179 patients, including 6,138 outpatients. Patients with higher LDH were more frequently female and had worse HF status. They were also more likely to have elevated serum creatinine, liver enzymes, creatine kinase, NT-proBNP, and high-sensitivity troponin I. Compared with patients in the lowest LDH (Q1: 155 U/L [25th-75th percentile: 144-163 U/L]), the HRs for the primary outcome (first HF event or cardiovascular death) were Q2: 183 U/L (25th-75th percentile: 177-188 U/L); HR: 1.15 [95% CI: 1.02-1.31 Hazard ratio does not have unit]; Q3: 207 U/L (25th-75th percentile: 201-215 U/L); HR: 1.39 [95% CI: 1.23-1.58]; and Q4: 253 U/L (25th-75th percentile: 236-280 U/L); HR: 1.84 [95% CI: 1.62-2.08], respectively. Even after adjustment, elevated LDH remained independently associated with higher HR. When added to the PREDICT-HF risk model, baseline LDH improved Harrell’s C statistic, IDI, and NRI for the primary outcome.
Conclusions:
In GALACTIC-HF, higher LDH levels were independently associated with a higher risk of clinical outcomes in HFrEF. (Global Approach to Lowering Adverse Cardiac Outcomes Through Improving Contractility in Heart Failure [GALACTIC-HF]; NCT02929329; EudraCT number: 2016-002299-28)
Data sources:
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