Compression

It is technically challenging to quantitatively apply strains to tune catalysis because most heterogeneous catalysts are nanoparticles, and lattice strains can only be applied indirectly via core-shell structures or crystal defects. Herein, we report quantitative relations between macroscopic strains and hydrogen evolution reaction (HER) activities of dealloyed nanoporous gold (NPG) by directly applying macroscopic strains upon bulk NPG. It was found that macroscopic compressive strains lead to a decrease, while macroscopic tensile strains improve the HER activity of NPG, which is in line with the d -band center model...

Can liquid-like and gas-like states be distinguished beyond the critical point, where the liquid-gas phase transition no longer exists and conventionally only a single supercritical fluid phase is defined? Recent experiments and simulations report strong evidence of dynamical crossovers above the critical temperature and pressure. Despite using different criteria, many existing theoretical explanations consider a single crossover line separating liquid-like and gas-like states in the supercritical fluid phase...

Probabilistic latent variable models (PLVMs), such as probabilistic principal component analysis (PPCA), are widely employed in process monitoring and fault detection of industrial processes. This article proposes a novel deep PPCA (DePPCA) model, which has the advantages of both probabilistic modeling and deep learning. The construction of DePPCA includes a greedy layer-wise pretraining phase and a unified end-to-end fine-tuning phase. The former establishes a hierarchical deep structure based on cascading multiple layers of the PPCA module to extract high-level features...

Cross-modal hashing (CMH) has attracted considerable attention in recent years. Almost all existing CMH methods primarily focus on reducing the modality gap and semantic gap, i.e., aligning multi-modal features and their semantics in Hamming space, without taking into account the space gap, i.e., difference between the real number space and the Hamming space. In fact, the space gap can affect the performance of CMH methods. In this paper, we analyze and demonstrate how the space gap affects the existing CMH methods, which therefore raises two problems: solution space compression and loss function oscillation...

Development of patient specific models of LV-MV interactions in ischemic mitral regurgitation (IMR) are complicated by the substantial variability and complex etiologies, making it difficult to extract underlying mechanisms. We thus developed a detailed ovine LV-MV finite element model based for the normal and acute post-MI states. The ovine LV FEM model was first extended to incorporate a detailed MV leaflet sub-model with a functionally-equivalent CT structure. The resulting complete LV-MV model was first used to simulate the full cardiac cycle in the normal state to establish baseline responses...

INTRODUCTION: Current treatment of spinal metastases (SM) aims on preserving spinal stability, neurological status, and functional status as well as achieving local control. It consists of spinal surgery followed by radiotherapy and/or systemic treatment. Adjuvant therapy usually starts with a delay of a few weeks to prevent wound healing issues. Intraoperative radiotherapy (IORT) has previously been successfully applied during brain tumor, breast and colorectal carcinoma surgery but not in SM, including unstable one, to date...

The superior thyroid cornu (STC) is a normal anatomic structure that forms part of the thyroid cartilage. Here, we report a patient with unusually elongated and ossified STC that might result in recurrent cerebral embolisms. During a second endovascular therapy for recurrent middle cerebral artery embolism, a segment with an irregular filling defect was noted in the internal carotid artery (ICA), at the C1 level. This defect was unnoticed during the initial endovascular procedure. Three-dimensional computed tomography angiography performed after the second endovascular procedure revealed an ICA segment located between the STC and C1 with a tortuous course and irregular wall of the ICA...

Anatomical variations are a common feature of the human anatomy. Variation can explain some pathological conditions and is important to keep them in mind during surgical procedures. The relations between nerves and their adjacent arteries have been proposed to play a role in the generation of peripheral trigger migraines. Close opposition between nerves and arteries can lead to vascular compression of the nerve that triggers episodes of pain. We did a routine dissection of the infratemporal fossa and orbital floor by opening the maxillary sinus...

PURPOSE: Chordomas are malignant tumors that destroy bones, compress surrounding nerve tissues and exhibit phenotypes that recapitulate notochordal differentiation in the axial skeleton. Chordomas recur frequently, as they resist radio-chemotherapy and are difficult to completely resect, leading to repeated bone destruction and local expansion via unknown mechanisms. Here, using chordoma specimens and JHC7 chordoma cells, we asked whether chordoma cells possess bone-dissolving activity...

Measurements of local density fluctuations are crucial to characterizing the interfacial properties of equilibrium fluids. A specific case that has been well-explored involves the heightened compressibility of water near hydrophobic entities. Commonly, a spatial profile of local fluctuation strength is constructed from the measurements of the mean and variance of solvent particle number fluctuations in a set of contiguous subvolumes of the system adjacent to the solvo-/hydrophobe. An alternative measure proposed by Evans and Stewart [J...

This study addresses a crucial necessity in the field of noninvasive liver fibrosis diagnosis by introducing the concept of continuous shear wave elastography (C-SWE), utilizing an external vibration source and color Doppler imaging. However, an application of C-SWE to assess liver elasticity, a deep region within the human body, arises an issue of signal instability in the obtained data. To tackle this challenge, this work proposes a method involving the acquisition of multiple frames of datasets, which are subsequently compressed...

The present study investigated the influence of SCUBA dives with compressed air at depths of 10 and 20 m on ECG-derived HRV parameters in apparently healthy individuals. We hypothesized that cardiac sympathetic activity (measured by HRV parameters) adapts proportionally to diving depth, and that both time- and frequency-domain parameters are sensitive enough to track changes in cardiac ANS function during diving activities and subsequently during the recovery period. Eleven healthy middle-aged recreational divers (nine men and two women, age 43 ± 8, all nonsmokers) volunteered to participate in the present study...

PURPOSE: To observe the growth and resolution of decompression gas bubbles in the spinal cord of live rats in real time using MRI. METHODS: We constructed an MRI-compatible pressure chamber system to visualize gas bubble dynamics in deep tissues in real time. The system pressurizes and depressurizes rodents inside an MRI scanner and monitors their respiratory rate, heart rate, and body temperature while providing gaseous anesthesia under pressure during the experiments...

SIGNIFICANCE: Compressed sensing (CS) uses special measurement designs combined with powerful mathematical algorithms to reduce the amount of data to be collected while maintaining image quality. This is relevant to almost any imaging modality, and in this paper we focus on CS in photoacoustic projection imaging (PAPI) with integrating line detectors (ILDs). AIM: Our previous research involved rather general CS measurements, where each ILD can contribute to any measurement...

BACKGROUND AND OBJECTIVE: Thyroid cancer, though relatively uncommon among all cancer types, stands as the primary form of endocrine tumor. Over the last 20 years, there has been a significant uptick in its occurrence. Papillary thyroid carcinoma (PTC), which is well-differentiated, emerges as the dominant subtype, in regions where iodine levels are deemed adequate. The study aimed to study the clinicopathological profile of patients diagnosed with thyroid malignancies at the Muslim Educational Society (MES) Medical College Perinthalmanna...

PURPOSE: This research aimed to describe the stress distribution of an endodontically treated tooth with a mesio-occluso-distal (MOD) cavity restored with direct composite reinforced with polyethylene and e-glass ribbon fiber. METHODS: This research was a descriptive study using the finite element method. A 3D model of the mandibular first molar solid after endodontic treatment with class II MOD preparation was prepared using Solidworks software. Finite element simulation was carried out using Abaqus software...

INTRODUCTION: Autonomic symptoms have been long recognized to occur with pain in the head, e.g., trigeminal neuralgia and trigeminal autonomic cephalalgias. Symptoms occur during pain attacks, so they are assumed to be activated by nociceptive afferents of the trigeminal nerve. Herein, we present a patient with hypersalivation that occurred following percutaneous balloon compression for trigeminal neuralgia, although being pain-free after the treatment. CASE PRESENTATION: The patient was a 71-year-old woman who experienced excessive salivation on the affected side after percutaneous balloon compression...

PURPOSE: To improve image quality, mitigate quantification biases and variations for free-breathing liver proton density fat fraction (PDFF) and <mml:math xmlns:mml="https://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:mrow><mml:msubsup><mml:mi>R</mml:mi> <mml:mn>2</mml:mn> <mml:mo>*</mml:mo></mml:msubsup> </mml:mrow> <mml:annotation>$$ {\mathrm{R}}_2^{\ast } $$</mml:annotation></mml:semantics> </mml:math> quantification accelerated by radial k-space undersampling...

STUDY DESIGN: Basic research. PURPOSE: This finite element (FE) analysis (FEA) aimed to compare the biomechanical parameters in multilevel posterior cervical fixation with the C7 vertebra instrumented by two techniques: lateral mass screw (LMS) vs. transpedicular screw (TPS). OVERVIEW OF LITERATURE: Very few studies have compared the biomechanics of different multilevel posterior cervical fixation constructs. METHODS: Four FE models of multilevel posterior cervical fixation were created and tested by FEA in various permutations and combinations...

STUDY DESIGN: A retrospective study at a single academic institution. PURPOSE: This study aimed to identify imaging risk factors for stenosis in extended neck positions undetectable in preoperative neutral magnetic resonance imaging (MRI) and improving decompression strategies for cervical spine disorders. OVERVIEW OF LITERATURE: Cervical disorders are influenced by various dynamic factors, with spinal stenosis appearing during neck extension...