Left anterior descending artery dissection with retrograde aortic dissection during percutaneous coronary intervention: a case report

Retrograde catheter-induced coronary artery dissection during percutaneous coronary intervention is an exceedingly rare occurrence, and the likelihood of it extending into the aorta is even more uncommon. Typically, surgical treatment involves aortic root replacement combined with coronary artery bypass grafting. However, in this particular case, a meticulous approach was employed. By carefully guiding wires into the true lumens and placing stents in the proximal left main and left anterior descending arteries, the immediate complications were averted by obstructing the retrograde flow in the false lumen. Subsequently, an off-pump coronary artery bypass was performed using the left internal mammary artery to the left anterior descending artery, without the need to manipulate the aorta. This approach resulted in a short operation time and the absence of any other complications

Uniportal video-assisted thoracoscopic anatomical resection of the right anterior pulmonary segment in a 10-year-old child with congenital pulmonary airway malformation

Abstract Congenital pulmonary airway malformation (CPAM) is a very rare phenomenon subject to malignant transformation that requires surgical resection. In an asymptomatic 10-year-old girl, we identified a single cystic and consolidated lesion on computed tomography. This incidental finding was confined to anterior segment of lung in right upper lobe (RUL). Uniportal video-assisted thoracoscopic surgery (VATS) served to successfully achieve anterior segmentectomy, without chest tube placement. The surgical specimen confirmed features of CPAM, also showing acute and chronic inflammation with abscess formation. Once the surgical mainstay for such lesions, open lobectomy is now under challenge by thoracoscopic technique, port-reduction methods, and a lung-preserving strategy. Herein, we have shown uniportal VATS anatomical resection of right anterior pulmonary segment to be a viable option for a 10-year-old child with CPAM confined to a single lung segment

Prediction of Blow-Up Potential Due to Concrete Pavement Growth

Concrete pavement growth can cause blow-ups and other pressure-related issues, such as concrete buckling and crushing at the transverse cracks or joints. In addition, these issues result in damaged to adjoining structures, such as bridge abutments, decks, and access structures in the pavement. However, available theoretical solutions and methods for evaluating pavement growth and predictions of concrete pavement blow-up are considerably limited. In this study, therefore, the pavement growth and blow-up analysis model was developed to predict the blow-up potential due to concrete pavement growth. This model considered factors such as the pavement structure and materials, climatic conditions, configuration of expansion joint, base friction characteristics, geometric imperfection, rotational stiffness of joints, and design reliability. In addition, the pavement growth and blow-up analysis model can be used to predict the service life of expansion joints and the blow-up occurrence time by considering the factors affecting it. Using the developed model, various sensitivity analysis was performed to investigate the factors affecting the potential concrete pavement growth and blow-up occurrence. It was found that the factors of substrate type, coefficient of thermal expansion, precipitation, and alkali–silica reaction had a significant effect on pavement growth and blow-up occurrence times

Nonintubated Uniportal Video-Assisted Thoracoscopic Surgery: A Single-Center Experience

Background: We report our surgical technique for nonintubated uniportal video-assisted thoracoscopic surgery (VATS) pulmonary resection and early postoperative outcomes at a single center. Methods: Between January and July 2017, 40 consecutive patients underwent nonintubated uniportal VATS pulmonary resection. Multilevel intercostal nerve block was performed using local anesthesia in all patients, and an intrathoracic vagal blockade was performed in 35 patients (87.5%). Results: Twenty-nine procedures (72.5%) were performed in patients with lung cancer (21 lobectomies, 6 segmentectomies, and 2 wedge resections), and 11 (27.5%) in patients with pulmonary metastases, benign lung disease, or pleural disease. The mean anesthesia time was 166.8 minutes, and the mean operative duration was 125.9 minutes. The mean postoperative chest tube duration was 3.2 days, and the mean hospital stay was 5.8 days. There were 3 conversions (7.5%) to intubation due to intraoperative hypoxemia and 1 conversion (2.5%) to multiportal VATS due to injury of the segmental artery. There were 7 complications (17.5%), including 3 cases of prolonged air leak, 2 cases of chylothorax, 1 case of pleural effusion, and 1 case of pneumonia. There was no in-hospital mortality. Conclusion: Nonintubated uniportal VATS appears to be a feasible and valid surgical option, depending on the surgeon’s experience, for appropriately selected patients

Post-glaciation depositional changes in Wijdefjorden, northern Svalbard, using grain-size end-member modelling

Grain-size end-member (EM) modelling is a robust statistical approach for identifying and quantifying dominant grain-size distributions. This approach provides a novel perspective for understanding the impact of interactions between depositional processes in complex sedimentary environments. This study examines grain-size distributions of six glacimarine sediment cores collected along an Nsingle bondS transect from the continental shelf to the Wijdefjorden system in northern Svalbard. In addition, we integrate grain-size EMs with lithologic and acoustic facies, allowing us to identify three distinct groups of EMs (EM1–3), each closely associated with specific depositional processes: turbid meltwater discharge (EM1), sediment winnowing by bottom currents (EM2), and the deposition of ice-rafted debris in glacimarine conditions and subglacial till (EM3). An analysis of the three EM groups reveals that the glacial retreat during the last deglaciation and the Atlantic Water inflow significantly impacted depositional changes within the Wijdefjorden system. In contrast, a decrease in the Atlantic Water inflow during the late Holocene corresponds to glacial re-advance, resulting in shifts in the depositional environment. This study demonstrates the utility of EM modelling in deciphering complex grain-size distributions and reconstructing different climate-driven depositional processes in glacimarine sediments in Svalbard fjords. This integrated approach enhances our understanding of the intricate interplay among climate change, glacier dynamics, and oceanic forcing in polar fjord environment

Non-linear response of glacier melting to Holocene warming in Svalbard recorded by sedimentary iron (oxyhydr)oxides

The recent acceleration of ice-sheet loss with its direct impact on sea-level rise and coastal ecosystems is of major environmental and societal concern. However, the effect of atmospheric temperature increases on long-term glacier retreat remains poorly defined due to limited historical observations and uncertainties in numerical ice-sheet models, which challenges climate change adaptation planning. Here, we present a novel approach for investigating the time-transgressive response of Arctic glaciers since the last deglaciation, using glacially-derived Fe-(oxyhydr)oxide layers preserved in glacimarine sediments from a large fjord system in Svalbard. Glacial weathering releases large amounts of Fe, resulting in the deposition of Fe-(oxyhydr)oxide particulates in nearby marine sediments, which can serve as fossil indicators of past glacial melting events. Our results indicate that Svalbard glaciers retreated at a rate of 18 to 41 m/yr between 16.3 and 10.8 kyr BP, synchronously with the progressive rise in atmospheric and oceanic temperatures. From 10.8 kyr BP, glacier retreat markedly accelerated (up to ∼116 m/yr) when regional atmospheric temperatures exceeded modern values. Coupled with field observations, this finding directly supports a non-linear response of glacial melting to summer air temperature increases. In addition to suggesting that ice-sheet loss and sea-level rise may further accelerate in the near future, this study paves the way for the use of sedimentary Fe-(oxyhydr)oxide layers in subarctic environments for reconstructing past glacial dynamic

Non-linear response of glacier melting to Holocene warming in Svalbard recorded by sedimentary iron (oxyhydr)oxides

The recent acceleration of ice-sheet loss with its direct impact on sea-level rise and coastal ecosystems is of major environmental and societal concern. However, the effect of atmospheric temperature increases on long-term glacier retreat remains poorly defined due to limited historical observations and uncertainties in numerical ice-sheet models, which challenges climate change adaptation planning. Here, we present a novel approach for investigating the time-transgressive response of Arctic glaciers since the last deglaciation, using glacially-derived Fe-(oxyhydr)oxide layers preserved in glacimarine sediments from a large fjord system in Svalbard. Glacial weathering releases large amounts of Fe, resulting in the deposition of Fe-(oxyhydr)oxide particulates in nearby marine sediments, which can serve as fossil indicators of past glacial melting events. Our results indicate that Svalbard glaciers retreated at a rate of 18 to 41 m/yr between 16.3 and 10.8 kyr BP, synchronously with the progressive rise in atmospheric and oceanic temperatures. From 10.8 kyr BP, glacier retreat markedly accelerated (up to ∼116 m/yr) when regional atmospheric temperatures exceeded modern values. Coupled with field observations, this finding directly supports a non-linear response of glacial melting to summer air temperature increases. In addition to suggesting that ice-sheet loss and sea-level rise may further accelerate in the near future, this study paves the way for the use of sedimentary Fe-(oxyhydr)oxide layers in subarctic environments for reconstructing past glacial dynamics

Tunable Encapsulation Structure of Block Copolymer Coated Single-Walled Carbon Nanotubes in Aqueous Solution

Nanosized and shape-tunable molecular building blocks can provide great opportunities for the fabrication of precisely controlled nanostructures. In this work, we have fabricated a molecular building block of single-walled carbon nanotubes (SWNTs) coated by PPO–PEO–PPO block copolymers whose encapsulation structure can be controlled via temperature or addition of small molecules. The structure and optical properties of SWNT block copolymers have been investigated by small-angle neutron scattering (SANS), ultraviolet–visible (UV–vis) spectroscopy, atomic force microscopy (AFM), and molecular dynamics (MD) simulation. The structure of the hydrated block copolymer layer surrounding SWNT can be controlled reversibly by varying temperature as well as by irreversibly adding 5-methylsalicylic acid (5MS). Increasing hydrophobicity of the polymers with temperature and strong tendency of 5MS to interact with both block copolymers and π orbitals of the SWNTs are likely to be responsible for the significant structural change of the block copolymer encapsulation layer, from loose corona shell to tightly encapsulating compact shell. Our result shows an efficient and simple way to fabricate and manipulate carbon-based nano building blocks in aqueous systems with tunable structure

Entropymetry for non-destructive structural analysis of LiCoO2 cathodes

Upon the emergence of electric vehicles, accurate and non-destructive monitoring of battery electrode materials during operation is highly desirable. Structural degradation of widely adopted intercalation-based materials constitutes the origin of their capacity fading and safety deterioration. Here, we introduce entropymetry to monitor the structural changes of LiCoO2 (LCO) and its nickel (Ni)-doped derivatives at different states of charge (SOC). While simple lithium (Li) extraction on charging gives a monotonic decline of entropy change (Delta S) based on progressive vacancy occupation over Li sites, the presence of a monoclinic intermediate phase inverses the slope of the Delta S profile to reflect its limited atomic configurations with high ordering. Furthermore, Ni-doping lessens the ordering of the monoclinic phase, decreasing the height amplitude of Delta S profile in the monoclinic regime. The increased disorder by Ni-doping enhances the stability of the lattice framework, extending the cycle life with high voltage cut-off (4.6 V vs. Li/Li+). The present study highlights entropymetry as a unique, non-destructive tool in monitoring the structural ordering and relevant degradation of electrode materials in lithium-ion batteries.