-
Cureus May 2024Pulmonary hamartomas (PH) are rare but are the most common benign tumors found in the lungs. They are slow-growing and are usually found incidentally on chest imaging...
Pulmonary hamartomas (PH) are rare but are the most common benign tumors found in the lungs. They are slow-growing and are usually found incidentally on chest imaging during the sixth decade of life. Approximately 10% of pulmonary hamartomas are endobronchial. Rarely, pulmonary hamartomas can cause a spectrum of pulmonary symptoms depending on their size and location. We present a case of endobronchial hamartoma causing airway obstruction and recurrent post-obstructive pneumonia.
PubMed: 38910726
DOI: 10.7759/cureus.60916 -
Korean Journal of Ophthalmology : KJO Jun 2024To Investigate the prognostic factors for recurrent rhegmatogenous retinal detachment (RRD) following silicone oil removal.
PURPOSE
To Investigate the prognostic factors for recurrent rhegmatogenous retinal detachment (RRD) following silicone oil removal.
METHODS
This retrospective review included 147 consecutive patients with RRD treated with silicone-oil tamponade at a high-volume referral-based tertiary hospital between January 2012 and May 2022. All patients underwent follow-up for a minimum of 6 months after subsequent silicone oil removal. The primary outcome measure was the rate of recurrent retinal detachment following silicone oil removal, and the secondary outcome was best-corrected visual acuity after silicone oil removal.
RESULTS
The mean silicone oil tamponade duration was 4.7 5.01 months (range: 1-38 months; median: 3 months), and the recurrent retinal detachment rate after silicone oil removal was 15.6%. Logistic regression analysis revealed that argon endolaser photocoagulation during silicone oil removal (odds ratio [OR]: 0.31;95% confidence interval [CI]: 0.106-0.898; p = 0.031) was associated with a lower rate of anatomical success after silicone oil removal. Demographics, preoperative ocular characteristics, proliferative vitreoretinopathy, previous scleral encircling or buckling, previous retinectomy, concomitant phacoemulsification, duration of silicone-oil tamponade, and gas tamponade after silicone oil removal were not significantly associated with recurrent retinal redetachment r after silicone oil removal. Duration of silicone-oil tamponade (OR: 1.23; 95% CI: 1.07-1.40; p = 0.003) and recurrent retinal detachment after silicone oil removal (OR, 3.40; 95% CI, 1.31-8.82; p = 0.012) were associated with poor visual outcomes after silicone oil removal.
CONCLUSIONS
Among all factors examined in this study, including the duration of silicone-oil tamponade, laser retinopexy was the only significant prognostic factor for recurrent retinal detachment after silicone oil removal. A longer duration of silicone oil tamponade was associated with worse visual outcomes and a lower rate of visual improvement after silicone oil removal.
PubMed: 38897593
DOI: 10.3341/kjo.2024.0011 -
Cureus May 2024In this case report, we describe a rare case of acute angle closure in an 18-year-old African-American female, attributed to plateau iris. The patient had...
In this case report, we describe a rare case of acute angle closure in an 18-year-old African-American female, attributed to plateau iris. The patient had no significant medical or ocular history and presented with high right-eye pressure, headache, and blurred vision. Ocular examination revealed findings consistent with acute angle closure, with gonioscopy confirming superior iris insertion anterior to Schwalbe's line and a "double hump" sign. Ultrasound biomicroscopy confirmed plateau iris. Treatment involved pharmacological management and bilateral peripheral laser iridoplasty. This case underscores the importance of considering plateau iris syndrome in the differential diagnosis of acute angle closure, even in younger patients, and highlights the role of early diagnosis and appropriate intervention in preventing vision loss.
PubMed: 38894792
DOI: 10.7759/cureus.60608 -
Materials (Basel, Switzerland) Jun 2024Addressing the issue of low bonding strength in Ti/Mg laminated composites due to interfacial oxidation, this study employs a differential temperature rolling method...
Addressing the issue of low bonding strength in Ti/Mg laminated composites due to interfacial oxidation, this study employs a differential temperature rolling method using longitudinal induction heating to fabricate Ti/Mg composite plates. The entire process is conducted under an argon gas protective atmosphere, which prevents interfacial oxidation while achieving uniform deformation. The effects of reduction on the mechanical properties and microstructure of the composite plates are thoroughly investigated. Results indicate that as the reduction increases, the bonding strength gradually increases, mainly attributed to the increased mechanical interlocking area and a broader element diffusion layer. This corresponds to a transition from a brittle to a ductile fracture at the microscopic tensile-shear fracture surface. When the reduction reaches 47.5%, the Ti/Mg interfacial strength reaches 63 MPa, which is approximately a 20% improvement compared to the bonded strength with previous oxidation at the interface. Notably, at a low reduction of 17.5%, the bonding strength is significantly enhanced by about one time. Additionally, it was found that a strong bonded interface at a high reduction is beneficial in hindering the propagation of interfacial cracks during tensile testing, enhancing the ability of the Ti/Mg composite plates to resist interfacial delamination.
PubMed: 38894017
DOI: 10.3390/ma17112753 -
Materials (Basel, Switzerland) Jun 2024A new hydrothermal hot isostatic pressing (HHIP) approach, involving hydrothermal water conditions and no usage of inert gas, was hypothesized and tested on 3D-printed...
A new hydrothermal hot isostatic pressing (HHIP) approach, involving hydrothermal water conditions and no usage of inert gas, was hypothesized and tested on 3D-printed Al-10%Si-0.3%Mg (%Wt) parts. The aluminum-based metal was practically inert at the applied HHIPing conditions of 300-350 MPa and 250-350 °C, which enabled the employment of a long (6-24 h) HHIP treatment with hardly any loss of material (the overall loss due to corrosion was mostly <0.5% /). Applying the new approach on the above-mentioned samples resulted in an 85.7% reduction in the AM micro-pores, along with a 90.8% reduction in the pores' surface area at a temperature of 350 °C, which is much lower than the 500-520 °C applied in common argon-based aluminum HIPing treatments, while practically maintaining the as-recieved microstructure. These results show that better mechanical properties can be expected when using the suggested treatment without affecting the material fatigue resistance due to grain growth. The proof of concept presented in this work can pave the way to applying the new HHIPing approach to other AM metal parts.
PubMed: 38893980
DOI: 10.3390/ma17112716 -
Materials (Basel, Switzerland) Jun 2024This article presents the research results of depositing anti-friction coatings (Babbitt) using three different casting methods: static casting, flame soldering, and...
This article presents the research results of depositing anti-friction coatings (Babbitt) using three different casting methods: static casting, flame soldering, and clad welding. Babbitt alloy coatings deposited with different casting methods are discussed and explained in terms of changes in the coating properties, such as the microstructure, hardness, strength, and chemical composition. The results showed significant differences in the aforementioned properties, depending on the chosen coating deposition method. The results of the tests confirmed the importance of using shielding gas during deposition to ensure the chemical composition of the coating. The analysis revealed that decreases in the amounts of antimony and copper in the Babbitt coating compared with the initial concentrations were influenced by selective evaporation, oxidation, and the coating process parameters associated with different coating methods. To maintain the desired balance of mechanical properties in Babbitt coatings, it is important to control the antimony and copper contents. Clad welding deposition using a non-consumable tungsten electrode and argon shielding gas achieved a chemically stable coating quite close to the initial chemical composition of the Babbitt alloy.
PubMed: 38893926
DOI: 10.3390/ma17112662 -
Molecules (Basel, Switzerland) Jun 2024The objective of this study was to investigate the modification of glass surfaces by the synergistic combination of cold plasma and chemical surface modification...
The objective of this study was to investigate the modification of glass surfaces by the synergistic combination of cold plasma and chemical surface modification techniques. Glass surface hydrophobicity was obtained as a result of various plasma and deposition operational conditions. The mechanisms governing the hydrophobization process were also studied. Glass plates were activated with plasma using different gases (oxygen and argon) at different treatment times, ranging from 30 to 1800 s. Then, the plasma-treated surfaces were exposed to hexamethyldisilazane vapors at different temperatures, i.e., 25, 60, and 100 °C. Complete characterization, including contact angle measurements, surface free energy calculations, 3D profilometry, X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, and scanning electron microscopy, was accomplished. It was found that the extent of the hydrophobicity effect depends on both the plasma pre-treatment and the specific conditions of the hexamethyldisilazane deposition process. Plasma activation led to the formation of active sites on the glass surface, which promoted the adsorption and reaction of hexamethyldisilazane species, thereby inducing surface chemical modification. Longer plasma pre-treatment resulted in stronger modification on the glass surface, resulting in changes in the surface roughness. The largest water contact angle of ≈100° was obtained for the surface activated by argon plasma for 1800 s and exposed to hexamethyldisilazane vapors at 25 °C. The changes in the surface properties were caused by the introduction of the hydrophobic trimethylsilyl groups onto the glass surface as well as roughness development.
PubMed: 38893520
DOI: 10.3390/molecules29112645 -
Molecules (Basel, Switzerland) May 2024A nanocomposite of multi-walled carbon nanotubes (MWCNTs) decorated with molybdenum dioxide (MoO) nanoparticles is fabricated through the reduction of phosphomolybdic...
A nanocomposite of multi-walled carbon nanotubes (MWCNTs) decorated with molybdenum dioxide (MoO) nanoparticles is fabricated through the reduction of phosphomolybdic acid hydrate on functionalized MWCNTs in a hydrogen-argon (10%) atmosphere in a tube furnace. The MoO/MWCNTs composite is proposed as an anodic modification material for microbial fuel cells (MFCs). MWCNTs have outstanding physical and chemical peculiarities, with functionalized MWCNTs having substantially large electroactive areas. In addition, combined with the exceptional properties of MoO nanoparticles, the synergistic advantages of functionalized MWCNTs and MoO nanoparticles give a MoO/MWCNTs anode a large electroactive area, excellent electronic conductivity, enhanced extracellular electron transfer capacity, and improved nutrient transfer capability. Finally, the power harvesting of an MFC with the MoO/MWCNTs anode is improved, with the MFC showing long-term repeatability of voltage and current density outputs. This exploratory research advances the fundamental application of anodic modification to MFCs, simultaneously providing valuable guidance for the use of carbon-based transition metal oxide nanomaterials in high-performance MFCs.
PubMed: 38893417
DOI: 10.3390/molecules29112541 -
Chemistry of Materials : a Publication... Jun 2024Recent advances in anion-redox topochemistry have enabled the synthesis of metastable mixed-anion solids. Synthesis of the new transition metal oxychalcogenide SrMnONaSe...
Recent advances in anion-redox topochemistry have enabled the synthesis of metastable mixed-anion solids. Synthesis of the new transition metal oxychalcogenide SrMnONaSe by topochemical Na intercalation into SrMnOSe is reported here. Na intercalation is enabled by the redox activity of [Se] perselenide dimers, where the Se-Se bonds are cleaved and a [Na Se] antifluorite layer is formed. Freshly prepared samples have 16(1) % Na-site vacancies corresponding to a formal oxidation state of Mn of +2.32, a mixed-valence between Mn (d) and Mn (d). Samples are highly prone to deintercalation of Na, and over two years, even in an argon glovebox environment, the Na content decreased by 4(1) %, leading to slight oxidation of Mn and a significantly increased long-range ordered moment on the Mn site as measured using neutron powder diffraction. The magnetic structure derived from neutron powder diffraction at 5 K reveals that the compound orders magnetically with ferromagnetic MnO sheets coupled antiferromagnetically. The aged sample shows a metamagnetic transition from bulk antiferromagnetic to ferromagnetic behavior in an applied magnetic field of 2 T, in contrast to the Cu analogue, SrMnOCuSe, where there is only a hint that such a transition may occur at fields exceeding 7 T. This is presumably due to the higher ionic character of [Na Se] layers compared to [Cu Se] layers, reducing the strength of the antiferromagnetic interactions between MnO sheets. Electrochemical Na intercalation into SrMnOSe leads to the formation of multiphase sodiated products. The work shows the potential of anion redox to yield novel compounds with intriguing physical properties.
PubMed: 38883431
DOI: 10.1021/acs.chemmater.4c00801 -
Medicine Jun 2024Argon gas poisoning is an often overlooked yet critical public health concern with the potential for severe and persistent neurological consequences. Current treatment...
RATIONALE
Argon gas poisoning is an often overlooked yet critical public health concern with the potential for severe and persistent neurological consequences. Current treatment protocols primarily focus on acute-phase management, but a comprehensive understanding of the long-term neurological effects remains incomplete.
PATIENT CONCERNS
A 22-year-old male worker was found unconscious in the furnace room of an argon production facility. After regaining consciousness, he presented with symptoms of dizziness, headache, fatigue, and irritability. Neurological examination revealed impairments in both recent and remote memory, notably pronounced short-term memory deficits and reduced arithmetic skills.
DIAGNOSIS
Argon gas poisoning, hypoxic encephalopathy, and mild hepatic and renal dysfunction.
INTERVENTIONS
Upon admission, symptomatic supportive measures included oxygen therapy via nasal cannula (3 L/min), daily hyperbaric oxygen therapy (1.5 ATA, 60 minutes), oral neurotrophic methylcobalamin (0.5 mg, 3 times daily), and intravenous vitamin C infusion (2 g daily) to scavenge oxygen free radicals.
OUTCOME
A 2-year telephone follow-up indicated persistent short-term memory impairment, particularly with memorizing numbers. In a memory test, he achieved a digit span forward of 5 but a digit span backward of 2, indicating impairment. Despite these challenges, his daily life and work performance remained largely unaffected.
LESSON
This case offers valuable insights into the biological mechanisms underlying prolonged neurological sequelae following asphyxiating gas exposure, specifically the persistent impairment of hippocampal function.
Topics: Humans; Male; Memory Disorders; Argon; Young Adult; Hyperbaric Oxygenation; Hypoxia, Brain
PubMed: 38875417
DOI: 10.1097/MD.0000000000038545