Urban methane emission monitoring across North America using TROPOMI data: an analytical inversion approach.

Monitoring methane emissions is crucial in mitigating climate change as it has a relatively short atmospheric lifetime of about 12 years and a significant radiative forcing impact. To measure the impact of methane-controlling policies and techniques, a deep understanding of methane emissions is of great importance. Remote sensing offers scalable approaches for monitoring methane emissions at various scales, from point-source high-resolution monitoring to regional and global estimates. The TROPOMI satellite instrument provides daily XCH4 data globally, offering the opportunity to monitor methane at a moderate spatial resolution with an acceptable level of sensitivity. To infer emissions from TROPOMI data, we used the prior emission estimates from global and national inventories and the GEOS-Chem chemical transport model to simulate atmospheric methane along with actual observations of TROPOMI. In this study, methane emissions from Toronto, Montreal, New York, Los Angeles, Houston, and Mexico City have been estimated using the analytical solution of Bayesian inversion using the cloud-based Integrated Methane Inversion (IMI) framework. Using the result from ensemble inversions, and city boundaries, the average total emissions were as follows: Toronto 230.52 Gg a-1, Montreal 111.54 Gg a-1, New York 144.38 Gg a-1, Los Angeles 207.03 Gg a-1, Houston 650.16 Gg a-1, and Mexico City 280.81 Gg a-1. The resulting gridded scale factors ranged from 0.22 to 6.2, implying methane prior emission underestimations in most of these cities. As such, this study underscores the key role of remote sensing in accurately assessing urban methane emissions, informing essential climate mitigation efforts.

Zeolite-Based Poly(vinylidene fluoride) Ultrafiltration Membrane: Characterization and Molecular Weight Cut-Off Estimation with Support Vector Regression Modelling.

Zeolite serves as a promising additive for enhancing the hydrophilicity of polymeric membranes, yet its utilization for bolstering the mechanical strength of the membrane remains limited. In this study, poly(vinylidene fluoride) (PVDF) membranes were modified by incorporating various concentrations of zeolite (0.5-2 wt%) to improve not only their mechanical properties, but also other features for water filtration. Membranes with and without zeolite incorporation were fabricated via a dry-wet phase inversion technique, followed by the application of a series of characterization techniques in order to study their morphological structure, mechanical strength, and hydrophilicity. The membrane filtration performance for each membrane was evaluated based on pure water flux and Bovine Serum Albumin (BSA) rejection. Field-Emission Scanning Electron Microscopy (FESEM) images revealed a dense, microvoid-free structure across all of the PVDF membranes, contributing to a high pristine PVDF membrane tensile strength of 14 MPa. The addition of 0.5 wt% zeolite significantly improved the tensile strength up to 19.4 MPa. Additionally, the incorporation of 1 wt% zeolite into PVDF membrane yielded improvements in membrane hydrophilicity (contact angle of 67.84°), pure water flux (63.49% increase), and high BSA rejection (95.76%) compared to pristine PVDF membranes. To further improve the characterization of the zeolite-modified PVDF membranes, the Support Vector Regression (SVR) model was adopted to estimate the molecular weight cut off (MWCO) of the membranes. A coefficient of determination (R2) value of 0.855 was obtained, suggesting that the SVR model predicted the MWCO accurately. The findings of this study showed that the utilization of zeolite is promising in enhancing both the mechanical properties and separation performance of PVDF membranes for application in ultrafiltration processes.

Regioisomerism vs Conformation: Impact of Molecular Design on the Emission Pathway in Organic Light-Emitting Device Emitters.

Despite the design and proposal of several new structural motifs as thermally activated delayed fluorescent (TADF) emitters for organic light-emitting device (OLED) applications, the nature of their interaction with the host matrix in the emissive layer of the device and their influence on observed photophysical outputs remain unclear. To address this issue, we present, for the first time, the use of up to four regioisomers bearing a donor-acceptor-donor electronic structure based on the desymmetrized naphthalene benzimidazole scaffold, equipped with various electron-donating units and possessing distinguished conformational lability. Quantum chemical calculations allow us to identify the most favorable conformations adopted by the electron-rich groups across the entire pool of regioisomers. These conformations were then compared with conformational changes caused by the interaction of the emitter with the Zeonex and 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP) matrices, and the correlation with observed photophysics was monitored by UV-vis absorption and steady-state photoluminescence spectra, combined with time-resolved spectroscopic techniques. Importantly, a CBP matrix was found to have a significant impact on the conformational change of regioisomers, leading to unique TADF emission mechanisms that encompass dual emission and inversion of the singlet-triplet excited-state energies and result in the enhancement of TADF efficiency. As a proof of concept, regioisomers with optimal donor positions were utilized to fabricate an OLED, revealing, with the best-performing dye, an external quantum emission of 11.6%, accompanied by remarkable luminance (28,000 cd/m2). These observations lay the groundwork for a better understanding of the role of the host matrix. In the long term, this new knowledge can lead to predicting the influence of the host matrix and adopting the structure of the emitter in a way that allows the development of highly efficient and efficient OLEDs.

Real-Time Optimal Synthetic Inversion Recovery Image Selection (RT-OSIRIS) for Deep Brain Stimulation Targeting.

Deep brain stimulation (DBS) is a method of electrical neuromodulation used to treat a variety of neuropsychiatric conditions including essential tremor, Parkinson's disease, epilepsy, and obsessive-compulsive disorder. The procedure requires precise placement of electrodes such that the electrical contacts lie within or in close proximity to specific target nuclei and tracts located deep within the brain. DBS electrode trajectory planning has become increasingly dependent on direct targeting with the need for precise visualization of targets. MRI is the primary tool for direct visualization, and this has led to the development of numerous sequences to aid in visualization of different targets. Synthetic inversion recovery images, specified by an inversion time parameter, can be generated from T1 relaxation maps, and this represents a promising method for modifying the contrast of deep brain structures to accentuate target areas using a single acquisition. However, there is currently no accessible method for dynamically adjusting the inversion time parameter and observing the effects in real-time in order to choose the optimal value. In this work, we examine three different approaches to implementing an application for real-time optimal synthetic inversion recovery image selection and evaluate them based on their ability to display continually-updated synthetic inversion recovery images as the user modifies the inversion time parameter. These methods include continuously computing the inversion recovery equation at each voxel in the image volume, limiting the computation only to the voxels of the orthogonal slices currently displayed on screen, or using a series of lookup tables with precomputed solutions to the inversion recovery equation. We find the latter implementation provides for the quickest display updates both when modifying the inversion time and when scrolling through the image. We introduce a publicly available cross-platform application built around this conclusion. We also briefly discuss other details of the implementations and considerations for extensions to other use cases.

Empowering powdered activated carbon (PAC) with 3D printing: Achieving highly efficient and reusable cationic dye removal.

Powdered activated carbon (PAC) has been extensively used as an effective adsorbent. Despite its excellent adsorption ability, PAC has drawbacks, including difficulty in filtration and reactivation after use, limitations of mass transfer in deeper areas because of its aggregated powder form, and limited applicability in high-flow systems. To overcome these limitations, we used a three-dimensional (3D) printing system to fabricate PAC into a 3D structure. Spectral and microscopic analyses indicated that PAC was embedded into 3D monolith and exhibited high porosity suitable for facile mass transfer. The designed 3D PAC filter effectively removed 200 ppm-methylene blue (MB) within 8 h and showed an adsorption efficiency of 93.4 ± 0.9%. The adsorption of MB onto the 3D PAC filter was described by the pseudo-first-order kinetic and Freundlich isotherm models. The negatively charged 3D PAC filter might attract the positively charged MB, thus favoring the physical adsorption of MB onto the 3D PAC filter. The adsorption performance of the 3D PAC filter was tested at various pH levels of 4-10 and against MB spiked in seawaters and freshwaters to evaluate its feasibility for use in real environments. Finally, the reproducibility and reusability of the 3D PAC filter were demonstrated through repeated adsorption and desorption processes against MB.

A novel application of data-consistent inversion to overcome spurious inference in genome-wide association studies.

The genome-wide association studies (GWAS) typically use linear or logistic regression models to identify associations between phenotypes (traits) and genotypes (genetic variants) of interest. However, the use of regression with the additive assumption has potential limitations. First, the normality assumption of residuals is the one that is rarely seen in practice, and deviation from normality increases the Type-I error rate. Second, building a model based on such an assumption ignores genetic structures, like, dominant, recessive, and protective-risk cases. Ignoring genetic variants may result in spurious conclusions about the associations between a variant and a trait. We propose an assumption-free model built upon data-consistent inversion (DCI), which is a recently developed measure-theoretic framework utilized for uncertainty quantification. This proposed DCI-derived model builds a nonparametric distribution on model inputs that propagates to the distribution of observed data without the required normality assumption of residuals in the regression model. This characteristic enables the proposed DCI-derived model to cover all genetic variants without emphasizing on additivity of the classic-GWAS model. Simulations and a replication GWAS with data from the COPDGene demonstrate the ability of this model to control the Type-I error rate at least as well as the classic-GWAS (additive linear model) approach while having similar or greater power to discover variants in different genetic modes of transmission.

Nonpuerperal uterine inversion caused by an adenosarcoma: A case report.

INTRODUCTION: Eighty-five per cent of uterine inversions are puerperal. Non-puerperal uterine inversion is usually caused by tumours that exert a traction force on the fundus of the uterus. This causes the uterus to be partially or completely inverted. It is commonly related to benign tumours like submucosal leiomyomas. Nevertheless, malignancies are an infrequent association. CASE PRESENTATION: We report a case of a 35-year-old female patient, medically and surgically free, gravida0 para0, complaining of menometrorrhagia associated with pelvic pain for 2 years. A suprapubic ultrasound scan showed an enlarged, globular uterus with a heterogeneous, undefined mass of 49 mm in size. MRI scan showed the appearance of a U-shaped uterine cavity and a thickened inverted uterine fundus with an endometrial infiltrating mass of 25 mm. Intraoperative exploration showed uterine inversion involving the ovaries; the fallopian tubes and the round ligaments and a necrotic intracavitary mass. The malignancy of the tumor was confirmed through anatomopathological examination as Adenosarcoma. CONCLUSIONS: Uterine inversion is rare outside the puerperal period, and malignant etiology must not be overlooked. Therefore, comprehensive care with meticulous etiological investigation is crucial.

Effect of rheological behaviors of polyacrylonitrile grafted sericin solution on film structure and mechanical properties.

Sericin protein possesses excellent biocompatibility, antioxidation, and processability. Nevertheless, manufacturing large quantities of strong and tough pure regenerated sericin materials remains a significant challenge. Herein, we design a lightweight structural sericin film with high ductility by combining radical chain polymerization reaction and liquid-solid phase inversion method. The resulting polyacrylonitrile grafted sericin films exhibit the ability to switch between high strength and high toughness effortlessly, the maximum tensile strength and Young's modulus values are 21.92 ± 1.51 MPa and 8.14 ± 0.09 MPa, respectively, while the elongation at break and toughness reaches up to 344.10 ± 35.40 % and 10.84 ± 1.02 MJ·m-3, respectively. Our findings suggest that incorporating sericin into regenerated films contributes to the transformation of their mechanical properties through influencing the entanglement of molecular chains within polymerized solutions. Structural analyses conducted using infrared spectroscopy and X-ray diffraction confirm that sericin modulates the mechanical properties by affecting the transition of condensed matter conformation. This work presents a convenient yet effective strategy for simultaneously addressing the recycling of sericin as well as producing regenerated protein-based films that hold potential applications in biomedical, wearable, or food packaging.

Gap-free X and Y chromosome assemblies of Salix arbutifolia reveal an evolutionary change from male to female heterogamety in willows, without a change in the position of the sex-determining locus.

In the Vetrix clade of Salix, a genus of woody flowering plants, sex determination involves chromosome 15, but an XY system has changed to a ZW system. We studied the detailed genetic changes involved. We used genome sequencing, with chromosome conformation capture (Hi-C) and PacBio HiFi reads to assemble chromosome level gap-free X and Y of Salix arbutifolia, and distinguished the haplotypes in the 15X- and 15Y-linked regions, to study the evolutionary history of the sex-linked regions (SLRs). Our sequencing revealed heteromorphism of the X and Y haplotypes of the SLR, with the X-linked region being considerably larger than the corresponding Y region, mainly due to accumulated repetitive sequences and gene duplications. The phylogenies of single-copy orthogroups within the SLRs indicate that S. arbutifolia and Salix purpurea share an ancestral SLR within a repeat-rich region near the chromosome 15 centromere. During the change in heterogamety, the X-linked region changed to a W-linked one, while the Z was derived from the Y.

Spontaneous intracranial hypotension: Exploring the viability of non-contrast FLAIR as a substitute for contrast-enhanced T1WI in assessing pachymeningeal thickening.

PURPOSE: To avoid contrast administration in spontaneous intracranial hypotension (SIH), some studies suggest accepting diffuse pachymeningeal hyperintensity (DPMH) on non-contrast fluid-attenuated inversion recovery (FLAIR) as an equivalent sign to diffuse pachymeningeal enhancement (DPME) on contrast-enhanced T1WI (T1ce), despite lacking thorough performance metrics. This study aimed to comprehensively explore its feasibility. METHODS: In this single-center retrospective study, between April 2021 and November 2023, brain MRI examinations of 43 patients clinically diagnosed with SIH were assessed using 1.5 and 3.0 Tesla MRI scanners. Two radiologists independently assessed the presence or absence of DPMH on FLAIR and DPME on T1ce, with T1ce serving as a gold-standard for pachymeningeal thickening. The contribution of the subdural fluid collections to DPMH was investigated with quantitative measurements. Using Cohen's kappa statistics, interobserver agreement was assessed. RESULTS: In 39 out of 43 patients (90.7%), pachymeningeal thickening was observed on T1ce. FLAIR sequence produced an accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of 72.1%, 71.8%, 75.0%, 96.6%, and 21.4% respectively, for determining pachymeningeal thickening. FLAIR identified pachymeningeal thickening in 28 cases; however, among these, 21 cases (75%) revealed that the pachymeningeal hyperintense signal was influenced by subdural fluid collections. False-negative rate for FLAIR was 28.2% (11/39). CONCLUSION: The lack of complete correlation between FLAIR and T1ce in identifying pachymeningeal thickening highlights the need for caution in removing contrast agent administration from the MRI protocol of SIH patients, as it reveals a major criterion (i.e., pachymeningeal enhancement) of Bern score.

Association of ADC of hyperintense lesions on FLAIR images with TERT promoter mutation status in glioblastoma IDH wild type.

Background: Although mutations in telomerase reverse transcriptase (TERT) promoter (TERTp) are the most common alterations in glioblastoma (GBM), predicting TERTp mutation status by preoperative imaging is difficult. We determined whether tumour-surrounding hyperintense lesions on fluid-attenuated inversion recovery (FLAIR) were superior to those of contrast-enhanced lesions (CELs) in assessing TERTp mutation status using magnetic resonance imaging (MRI). Methods: This retrospective study included 114 consecutive patients with primary isocitrate dehydrogenase (IDH)-wild-type GBM. The apparent diffusion coefficient (ADC) and volume of CELs and FLAIR hyperintense lesions (FHLs) were determined, and the correlation between MRI features and TERTp mutation status was analyzed. In a subset of cases, FHLs were histopathologically analyzed to determine the correlation between tumor cell density and ADC. Results: TERTp mutations were present in 77 (67.5%) patients. The minimum ADC of FHLs was significantly lower in the TERTp-mutant group than in the TERTp-wild-type group (mean, 958.9 × 10-3 and 1092.1 × 10-3 mm2/s, respectively, P < 0.01). However, other MRI features, such as CEL and FHL volumes, minimum ADC of CELs, and FHL/CEL ratio, were not significantly different between the two groups. Histopathologic analysis indicated high tumor cell density in FHLs with low ADC. Conclusion: The ADC of FHLs was significantly lower in IDH-wild-type GBM with TERTp mutations, suggesting that determining the ADC of FHLs on preoperative MRI might be helpful in predicting TERTp mutation status and surgical planning.

Reversed-Image Mechanical Thrombectomy for Acute Ischemic Stroke in a Situs Inversus Totalis Patient.

An 85-year-old female with situs inversus totalis presented with right hemiplegia, right facial nerve palsy, eye deviation to the left, and aphasia. Magnetic resonance imaging revealed acute ischemic lesions in the left insular cortex and the frontal lobe. Magnetic resonance angiography revealed an occlusion of the left internal carotid artery. Reversed-image mechanical thrombectomy achieved complete reperfusion in three passes within 54 minutes. Six months post-intervention, the patient could walk indoors independently. Our technique, which replicates the normal arterial anatomy by inversion and angulation, was adapted to situs inversus totalis.

Spinet-QSM: model-based deep learning with schatten p-norm regularization for improved quantitative susceptibility mapping.

OBJECTIVE: Quantitative susceptibility mapping (QSM) provides an estimate of the magnetic susceptibility of tissue using magnetic resonance (MR) phase measurements. The tissue magnetic susceptibility (source) from the measured magnetic field distribution/local tissue field (effect) inherent in the MR phase images is estimated by numerically solving the inverse source-effect problem. This study aims to develop an effective model-based deep-learning framework to solve the inverse problem of QSM. MATERIALS AND METHODS: This work proposes a Schatten p -norm-driven model-based deep learning framework for QSM with a learnable norm parameter p to adapt to the data. In contrast to other model-based architectures that enforce the l 2 -norm or l 1 -norm for the denoiser, the proposed approach can enforce any p -norm ( 0 < p ≤ 2 ) on a trainable regulariser. RESULTS: The proposed method was compared with deep learning-based approaches, such as QSMnet, and model-based deep learning approaches, such as learned proximal convolutional neural network (LPCNN). Reconstructions performed using 77 imaging volumes with different acquisition protocols and clinical conditions, such as hemorrhage and multiple sclerosis, showed that the proposed approach outperformed existing state-of-the-art methods by a significant margin in terms of quantitative merits. CONCLUSION: The proposed SpiNet-QSM showed a consistent improvement of at least 5% in terms of the high-frequency error norm (HFEN) and normalized root mean squared error (NRMSE) over other QSM reconstruction methods with limited training data.

Reversing the Trend: Deciphering Self-Assembly of Unconventional Amphiphiles having both Alkyl-chain and PEG.

In the field of molecular self-assembly, the core of an assembly is always made up of hydrophobic moiety like a long alkyl chain, whereas the outer part has always been a hydrophilic moiety such as poly(ethylene glycol) (PEG), or charged species. Hence, reversing the trend to manifest self-assembled structures with a PEG core and a surface consisting of alkyl chains in aqueous system is incredibly challenging. Herein, we architected a unique class of cationic bolaamphiphiles containing low molecular weight PEG and alkyl chains of different lengths. The bolaamphiphiles spontaneously form vesicles without external stimuli. These vesicles are unprecedented because PEG makes up the vesicle core, while the alkyl chains appear on the vesicles' exterior. Hence, this is the first report on an assembly that reverses the usual trend. The vesicle size increases with the increase in alkyl chain-length. To our great surprise, we obtained large micelles for longest alkyl-chain amphiphile, which in turn act as a gemini amphiphile. The shift from a particular bolaamphiphile to gemini amphiphile with the variation of alkyl chain is also unexplored. Therefore, this specific class of self-assembled structure would compound a new paradigm in the fields of molecular self-assembly and supramolecular chemistry.

Chromosome-scale genome assembly of the rough periwinkle Littorina saxatilis.

The intertidal gastropod Littorina saxatilis is a model system to study speciation and local adaptation. The repeated occurrence of distinct ecotypes showing different levels of genetic divergence makes L. saxatilis particularly suited to study different stages of the speciation continuum in the same lineage. A major finding is the presence of several large chromosomal inversions associated with the divergence of ecotypes and, specifically, the species offers a system to study the role of inversions in this divergence. The genome of L. saxatilis is 1.35Gb and composed of 17 chromosomes. The first reference genome of the species was assembled using Illumina data, was highly fragmented (N50 of 44kb) and was quite incomplete, with a BUSCO completeness of 80.1% on the Metazoan dataset. A linkage map of one full-sibling family enabled the placement of 587 Mbp of the genome into 17 linkage groups corresponding to the haploid number of chromosomes, but the fragmented nature of this reference genome limited the understanding of the interplay between divergent selection and gene flow during ecotype formation. Here we present a newly generated reference genome that is highly contiguous, with a N50 of 67 Mb and 90.4% of the total assembly length placed in 17 super-scaffolds. It is also highly complete with a BUSCO completeness of 94.1 % of the Metazoa dataset. This new reference will allow for investigations into the genomic regions implicated in ecotype formation as well as better characterization of the inversions and their role in speciation.

Amine-Functionalized Meso-Macroporous Polymers for Efficient CO2 Capture from Ambient Air.

Over the past decade, direct air capture (DAC) of carbon dioxide (CO2) using solid nanoadsorbents has garnered attention as a negative emission technology with high energy efficiency. Although operational, the large-scale deployment of DAC technologies has been significantly delayed due to the low performance and high cost of solid DAC nanoadsorbents. Herein, we present a novel family of meso-macroporous melamine formaldehyde (MF) materials with a facile preparation methodology, low capital cost, and unique physicochemical characteristics for DAC. The fabricated MF materials exhibit an extra-large pore volume of 5.19 cm3/g with a 24.6 nm average pore diameter. We show that the synthesized MF materials can be used as substrates and impregnated with different amounts of tetraethylenepentamine (TEPA) to act as chemical nanoadsorbents for DAC. Owing to the ultrahigh pore volume of MF, a substantial amount of 71 wt % TEPA (i.e., MF-TEPA71%) can be loaded, resulting in 2.65 mmol/g of CO2 uptake under DAC conditions. In addition, the superior physicochemical properties of MF lead to a high CO2 loading of 2.07 mmol/g with low TEPA loading in MF-TEPA33%. The prepared MF-TEPA nanoadsorbents can be successfully employed in different shapes (i.e., droplets, pellets, and coatings) and maintain their superiority across different temperatures and CO2 concentrations. This study provides a promising approach for developing meso-macroporous substrates through a straightforward and scalable synthesis method, representing a new avenue for the next generation of DAC nanoadsorbents with superior performance for practical applications.

Simulation of acquisition shifts in T2 weighted fluid-attenuated inversion recovery magnetic resonance images to stress test artificial intelligence segmentation networks.

Purpose: To provide a simulation framework for routine neuroimaging test data, which allows for "stress testing" of deep segmentation networks against acquisition shifts that commonly occur in clinical practice for T2 weighted (T2w) fluid-attenuated inversion recovery magnetic resonance imaging protocols. Approach: The approach simulates "acquisition shift derivatives" of MR images based on MR signal equations. Experiments comprise the validation of the simulated images by real MR scans and example stress tests on state-of-the-art multiple sclerosis lesion segmentation networks to explore a generic model function to describe the F1 score in dependence of the contrast-affecting sequence parameters echo time (TE) and inversion time (TI). Results: The differences between real and simulated images range up to 19% in gray and white matter for extreme parameter settings. For the segmentation networks under test, the F1 score dependency on TE and TI can be well described by quadratic model functions (R2>0.9). The coefficients of the model functions indicate that changes of TE have more influence on the model performance than TI. Conclusions: We show that these deviations are in the range of values as may be caused by erroneous or individual differences in relaxation times as described by literature. The coefficients of the F1 model function allow for a quantitative comparison of the influences of TE and TI. Limitations arise mainly from tissues with a low baseline signal (like cerebrospinal fluid) and when the protocol contains contrast-affecting measures that cannot be modeled due to missing information in the DICOM header.

Combination of Contrast-enhanced FlAIR and Contrast-enhanced T1WI: A Quick and Efficient Method in Detecting Brain Metastases of Lung Cancers.

BACKGROUND: Some patients with suspected brain metastases (BM) could not tolerate longer scanning examinations according to the standardized MRI protocol. OBJECTIVE: The purpose of this study was to evaluate the clinical value of contrast-enhanced fast fluid-attenuated inversion recovery (CE FLAIR) imaging in combination with contrast-enhanced T1 weighted imaging (CE T1WI) in detecting BM of lung cancer and explore a quick and effective MRI protocol. MATERIAL AND METHODS: In 201 patients with lung cancers and suspected BM, T1WI and FLAIR were performed before and after administration of gadopentetate dimeglumine. Two radiologists reviewed pre- and post-contrast images to determine the presence of abnormal contrast enhancement or signal intensity and decided whether it was metastatic or not on CE T1WI (Group 1) and CE FLAIR (Group 2). The number, locations and features of abnormal findings in two groups were recorded. Receiver Operating Characteristic (ROC) analyses were conducted in three groups: Group 1, 2 and 3(combination of CE FLAIR and CE T1WI). RESULTS: A total of 714 abnormal findings were revealed, of which 672 were considered as BM and 42 nonmetastatic. Superficial and small metastases(≤10mm) in parenchyma and ependyma, leptomeningeal and non-expansive skull metastases were typically better seen on CE FLAIR. The areas under ROC in the three groups were 0.720,0.887 and 0.973, respectively. Group 3 was significantly better in diagnostic efficiency of BMs than Group 1 (p<0.0001) or Group 2 (p=0.0006). CONCLUSION: The combination of CE T1WI and CE FLAIR promotes diagnostic performance and results in better observation and characterization of BM in patients with lung cancers. It provides a quick and efficient way of detecting BM.

Left atrial appendage inversion: First computational study to shed light on the phenomenon.

Inversion of the left atrial appendage is a rare phenomenon, which may occur during the de-airing maneuvers associated to routinely performed surgery procedures, such as cardiopulmonary bypass or left ventricular assist device implantation. In this case, the body of the inverted appendage can obstruct the mitral valve leading to severe complications. The mechanisms are still poorly known, and more specific studies are needed to better understand its causes and identify mitigating strategies. The current study attempts to gain a better comprehension of the conditions and the factors favourable to left atrial appendage inversion. Four patient specific appendage morphologies, obtained from computerised tomography and representative of the main typologies commonly used for the appendage classification (chicken wing, cactus, cauliflower, and windsock), were used for the study. The numerical models were subjected to the same loading pattern, made of subsequent different pressure curves. Results show that the morphologies invert and recover their original anatomical configuration at different pressure loads, indicating that their tendency to invert is associated to their specific morphological features. Moreover, the analysis highlights that, although restoring the physiological left atrium pressure is not sufficient to induce appendage recovery, pressures well below the ventricular ones can induce the return to the natural configuration. All models recovered the anatomical configuration at pressures well below the ventricular pressure (about 100 mmHg), suggesting that basic trans-catheter maneuvers, e.g. producing temporary mitral regurgitation, could be attempted to correct the appendage configuration, prior to opt for more invasive surgical approaches.