Correlation between Genetic Characteristics, Cell Structure and Material Properties of Moso Bamboo (Phyllostachys edulis (Carriere) J. Houzeau) in Different Areas of China

Moso bamboo (Phyllostachys edulis (Carriere) J. Houzeau), native to China, is one of the most economically and ecologically important bamboo species. Since the economic interests and the strong clonality, it has been widely cultivated in southern China, which inevitably reduces the natural stands and leads to gene loss in this species. In this study, three natural populations of Moso bamboo distributed in Anhui, Guangxi, and Zhejiang province, were used to analyze the correlation between phenotypic traits, cell structure, and material properties from the perspective of phenotypic, genetic, and environmental. Among those traits and properties, fiber width was correlated with wall thickness at breast height and average nodes length under branch positively. Leaf length was correlated positively with fiber lumen diameter and parenchyma lumen diameter. Furthermore, it showed a very close correlation between moisture content, bending strength, modulus of elasticity, and diameter at breast height, clear height, and leaf length. The lumen diameter of fiber cell wall thickness is positively correlated with bending strength and modulus of elasticity. Density is positively correlated with parenchyma cell wall thickness. The experimental design is relatively detailed and representative, and the workload is huge. This study reflects the research objectives with scientific and rational experiments and data. This study will analyze the differences of various indicators from the perspective of genetic to build a bridge between micro-structure and macro-structure for rational utilization of the whole area of Moso bamboo resources in China.

Diameter measurements in three-dimensional printed flow phantom model of the carotid artery in preterm infants

Diameter form an integral part of blood flow measurement. This study aimed to explore different three-dimensional (3D) printed materials to develop flow phantom models of the carotid artery in preterm newborn infants and to investigate ideal diameter measurement points using ultrasound that reflected accurate lumen diameter measurement. Cerebral blood flow measurements data using Doppler ultrasound of the right common carotid artery from 21 randomly selected preterm infants were used to produce a 3D printed Doppler flow phantom model with three different vessel diameters. Diameters were measured by multiple observers blinded to phantom vessel characteristics and each other’s measurements. 9 measurement points were studied. Agreement between observers, inter and intra observer reliability and coefficient of variation (CoV) was examined. Of the 63 diameter measurements, 45 (71%) were performed on flow phantoms with vessel diameter of 0.196 cm. Bland-Altman plots revealed that measurement performed using leading edge to centre (mean bias 1.8% {95%LOA -4.1% to 7.7%}) and centre to trailing edge (mean bias 1.1% {95%LOA -5.4% to 7.8%}) resulted in the most accurate lumen diameter measurements. Inter and intra-observer reliability was excellent. The mean CoV for inter observer measurements was 1.7% and intra observer measurements was 1.6% and 1.8% for each observer. We successfully produced a 3D printed flow phantom model of the carotid artery in preterm infants and identified two measurement methods that result in reliable and accurate lumen diameter measurement. Researchers and clinicians can use this information for further studies involving ultrasound diameter measurements in small calibre vessels.

Cerebral Hemodynamics and Carotid Atherosclerosis in Patients With Subcortical Ischemic Vascular Dementia

A growing body of evidence indicates that atherosclerosis is correlated with cerebral small vessel disease and contributes to cognitive decline. This study aimed to explore the characteristics and contributions of intracranial hemodynamics and carotid atherosclerosis to cognitive dysfunction in subjects with subcortical ischemic vascular dementia (SIVD). Notably, 44 patients with SIVD, 30 patients with Alzheimer’s disease (AD), and 30 healthy controls (HCs) were recruited from our longitudinal MRI study for AD and SIVD (ChiCTR1900027943). The cerebral mean flow velocity (MFV) and pulsatility index (PI) of both anterior and posterior circulations, artery plaque, and lumen diameter in carotid arteries were investigated using transcranial Doppler and carotid ultrasound, respectively. Their correlations with cognitive function were analyzed in patients with dementia. Decreased MFV and increased PI were found in patients with SIVD and AD. Patients with SIVD showed lower MFV and higher PI in the bilateral posterior cerebral arteries compared to patients with AD. Increases in lumen diameter, number of arteries with plaque, and total carotid plaque score were found in patients with SIVD. The Mini-Mental State Examination score was positively correlated with the MFV and negatively correlated with the PI of most major cerebral arteries, while it was negatively correlated with the lumen diameter of the common carotid artery, number of arteries with plaque, and total carotid plaque score in patients with dementia. There were also correlations between these parameters of some arteries and memory and executive function. Our results provide additional evidence suggesting that the pathological changes in macrovascular structure and function are correlated with cognitive impairment in dementia patients with SIVD and to a lesser extent AD.

Diagnostic Performance of Frequency-Domain Optical Coherence Tomography to Predict Functionally Significant Left Main Coronary Artery Stenosis

Aims. The aim of this study was to assess the safety and diagnostic efficacy of frequency-domain optical coherence tomography (FD-OCT) in identifying functional severity of the left main coronary artery (LM) stenosis determined by fractional flow reserve (FFR). Methods and Results. 101 patients with LM lesion (20–70% diameter stenosis angiographically) underwent FFR measurement and FD-OCT imaging of the LM. The following parameters were measured by FD-OCT in the LM: reference lumen area (RLA), reference lumen diameter (RLD), minimum lumen area (MLA), minimum lumen diameter (MLD), % lumen area stenosis, and % diameter stenosis. The LM lesions were analyzable by FD-OCT in 88/101 (87.1%) patients. FFR at maximum hyperemia was ≤0.80 in 39/88 (44.3%) patients. FFR values were correlated significantly with FD-OCT-derived LM lumen parameters. An MLA cutoff value of 5.38 mm2 had the highest sensitivity and specificity of 82% and 81%, respectively, followed by an MLD of 2.43 mm (sensitivity 77%, specificity 72%) and AS of 60% (sensitivity 72%, specificity 72%) for predicting FFR <0.80. Conclusions. FD-OCT is a safe and feasible imaging technique for the assessment of LM stenosis. An FD-OCT-derived MLA of ≤5.38 mm2 strongly predicts the functional severity of an LM lesion.

Abstract 1122‐000112: In Vitro Investigation of Endothelial Injury During Mechanical Thrombectomy for Ischemic Stroke

Introduction : Ischemic stroke (IS) makes up a significant proportion of all strokes, of which large vessel occlusions (LVO) are the most debilitating type. The current clinical standard‐of‐care for IS includes mechanical thrombectomy with stent retrievers. One of the impediments to the success of SR intervention is endothelial injury (EI), which can occur in approximately 30% of cases and impedes vessel reperfusion. Since successful reperfusion of the occluded vessel is instrumental in survival and patient recovery, it is imperative to reduce device injury‐based complications such as vasospasm, and to improve patient outcomes. Methods : In this work, our hypothesis is that EI can be reduced by investigating the mechanisms of stent retriever‐induced injury in vitro using live cell 3D cerebrovascular models. Using true‐scale cerebrovascular phantoms with lumen diameter approximately 4 mm created using 3D printing and PDMS casting, Human Umbilical Vein Endothelial Cells (HUVECs) were seeded on the luminal surface. The in vitro models were coated with fibronectin (density 4 µgrams/cm2) to encourage cell adhesion, and were divided into control and treated samples (n = 3 each). Mechanical thrombectomy was performed using two different clinically used SR (Trevo XP PROVUE 3 × 20 mm and Trevo XP PROVUE 6 × 30 mm) to investigate the extent of stent retriever size on EI on the same diameter lumen. Following thrombectomy, the cerebrovascular models were fixed and stained with immunofluorescent dyes (DAPI, Phalloidin and VE cadherin antibody) and imaged using transmitted light, confocal microscopy and scanning electron microscopy. For quantitative assessment, real time PCR was performed on both control and treated samples. Results : All models were initially confluent and functional, as assessed by immunofluorescent staining (Figure 1 A and B). All treated samples demonstrated EI and endothelial damage, as evidenced by loss of endothelial cell coverage, denuding of the models, stripping / clumping of endothelial cells into non‐physiological three dimensional structures and physical scratching of the in vitro model (Figure 1 C and D). Sizing of stent retriever had a strong influence on the effects on the endothelium, with larger sizes causing more damage. Conclusions : A significant knowledge gap exists in understanding the factors responsible for disruption of the endothelium during mechanical thrombectomy. Using a 3D in vitro platform of cerebrovasculature, we demonstrated that endothelial damage occurs during thrombectomy using stent retrievers. A parameteric investigation is currently ongoing that characterizes the influence of vessel lumen diameter, stent retriever size, number of passes and patient specific vasculature. This work can provide guidelines for optimal stent retriever devices to be used where possible, ultimately reducing EI and improving outcomes of ischemic stroke treatment.

Assessment of New Coronary Features on Quantitative Coronary Angiographic Images With Innovative Unsupervised Artificial Adaptive Systems: A Proof-of-Concept Study

Background and Purpose: The Active Connection Matrixes (ACMs) are unsupervised artificial adaptive systems able to extract from digital images features of interest (edges, tissue differentiation, etc.) unnoticeable with conventional systems. In this proof-of-concept study, we assessed the potentiality of ACMs to increase measurement precision of morphological structures (e.g., stenosis and lumen diameter) and to grasp morphological features (arterial walls) from quantitative coronary angiography (QCA), unnoticeable on the original images.Methods: Archive images of QCA and intravascular ultrasound (IVUS) of 10 patients (8 men, age 69.1 ± 9.7 years) who underwent both procedures for clinical reasons were retrospectively analyzed. Arterial features derived from “IVUS images,” “conventional QCA images,” and “ACM-reprocessed QCA images” were measured in 21 coronary segments. Portions of 1-mm length (263 for lumen and 526 for arterial walls) were head-to-head compared to assess quali-quantitative between-methods agreement.Results: When stenosis was calculated on “ACM-reprocessed QCA images,” the bias vs. IVUS (gold standard) did not improve, but the correlation coefficient of the QCA–IVUS relationship increased from 0.47 to 0.83. When IVUS-derived lumen diameters were compared with diameters obtained on ACM-reprocessed QCA images, the bias (−0.25 mm) was significantly smaller (p &lt; 0.01) than that observed with original QCA images (0.58 mm). ACMs were also able to extract arterial wall features from QCA. The bias between the measures of arterial walls obtained with IVUS and ACMs, although significant (p &lt; 0.01), was small [0.09 mm, 95% CI (0.03, 0.14)] and the correlation was fairly good (r = 0.63; p &lt; 0.0001).Conclusions: This study provides proof of concept that ACMs increase the measurement precision of coronary lumen diameter and allow extracting from QCA images hidden features that mirror well the arterial walls derived by IVUS.

A comparative fiber morphological analysis of major agricultural residues (used or investigated) as feedstock in the pulp and paper industry

The suitabilities of major agricultural residues were assessed as papermaking feedstocks. All the examined agricultural residues were assumed as potential candidates for substituting hardwood fibers in mixed pulp blends from a fiber morphological perspective. Wheat, barley, rice, rapeseed, maize, sunflower, sugarcane bagasse, coconut husk, and two genotypes of miscanthus grass underwent identical maceration. The fiber length, fiber width, cell wall thickness, and lumen diameter were measured to calculate the slenderness ratio, flexibility coefficient, and Runkel ratio. The average fiber length ranged from 0.50 mm ± 0.32 mm (MG-S-02-V) to 1.15 mm mm ± 0.58 mm (sugarcane bagasse). The fiber width ranged from 10.77 μm ± 3.28 μm (rice straw) to 22.99 mm ± 5.20 mm (sunflower stalk). The lumen diameter ranged from 4.52 μm ± 2.52 μm (rice straw) to 13.23 μm ± 4.87 μm (sunflower stalk). The cell wall thickness ranged from 3.02 μm ± 0.95 μm (rice straw) to 4.80 μm ± 1.48 μm (sunflower stalk). The slenderness ratio, flexibility coefficient, and Runkel ratio values ranged between 28.08 to 58.11, 37.97 to 60.8, and 0.62 to 1.68, respectively. Wheat, maize, rapeseed, sugarcane bagasse, and coconut husk were found to be appropriate residue sources for papermaking feedstocks.

Do we know how much force we apply with latex intermaxillary elastics?

Objectives: The aim of our study was to evaluate the variation of the forces provided by different branded elastics and to compare the force diminution that occurs after 24-h of use in wet environment. Materials and Methods: Elastics from four different manufacturer (American Orthodontics [AO], USA; Dentaurum [DENT], Germany; Ormco, USA; RMO, USA) with 3/16-inch (4.8 mm) lumen diameter, and two different force degrees (medium/heavy) were included in the study with a total of eight groups of elastics. First force measurements were performed with 50 elastics of each group at various stretching distances; lumen diameter ×2 (9.52 mm), ×3 (14.28 mm), the average canine-first molar length (22.3 mm), and the canine-second molar length (38.7 mm) under room temperature and dry air conditions. In addition, ten the elastics from each group were stretched at 22.3 mm distance in a custom-made plate and kept in 37°C distilled water. Twenty-four hours later, the force measurements were repeated. Results: Regardless of the brand and type (medium-heavy), all the tested elastics showed variations in matter of generated forces at different stretching distances. The variation amount increased as the length of elongation increased. The lowest standard deviation values were observed for both medium and heavy DENT elastic groups. When stretched to 3 times of their lumen size, the medium and heavy elastics both produced either lower or higher forces compared to the levels of force indicated by the manufacturers. The closest mean force to the force level stated by the manufacturer was provided with medium AO (3.6 g difference) elastics and heavy RMO counterparts (7.9 g difference). A significant 20–23% reduction of force was observed in all brands, both in medium and heavy elastics after passing 24-h in aqueous environment. No significant difference was observed in matter of force degradation between groups for both medium and heavy elastics (P < 0.05). Conclusion: The forces exerted by intermaxillary elastics were not found to be standard and the force stated on the package is not always provided precisely. A significant force loss around 20% was observed with all the elastics after 24-h of use in wet environment at 37°C.

Prediction of the functional significance of the left main stenosis using frequency domain optical coherence tomography

Background Frequency domain optical coherence tomography (FD-OCT) has been used for the assessment of non-ostial left main coronary artery stenosis (LM). However, no study has evaluated the use of this imaging technique for the prediction of functional significance of LM lesions determined by the fractional flow reserve (FFR). Purpose The aim of this study was to assess the safety and diagnostic efficacy of FD-OCT in identifying functional severity of the LM stenosis determined by (FFR). Methods One hundred one patients with LM lesion (20–70% diameter stenosis angiographically) underwent FFR measurement and FD-OCT imaging of the LM. The following parameters were measured by FD-OCT in the LM: reference lumen area (RLA), reference lumen diameter (RLD), minimum lumen area (MLA), minimum lumen diameter (MLD), % lumen area stenosis, % diameter stenosis. Results The LM lesions were visible and measurable by FD-OCT in 88/101 (87.1%) patients. However lesions with ostial location were analyzable by FD-OCT only in 17/30 (56.4%) patients (Figure 1). FFR at maximum hyperemia was ≤0.80 in 39/88 (44.3%) patients. FFR values were correlated significantly with FD-OCT derived LM lumen parameters. Receiver operating characteristic curves showed that an MLA cutoff value of 5,38 mm2 had the highest sensitivity and specificity of 82% and 81% respectively (Figure 2A), followed by an MLD of 2.43 mm (sensitivity 77%, specificity 72%) (Figure 2B) and an %AS of 60% (sensitivity 72%, specificity 72%) (Figure 2C) for predicting FFR ≤0.80. Conclusions FD-OCT is safe and feasible imaging technique for the assessment of a LM stenosis except the ostial LM lesions which are analyzable in half of the cases. An FD-OCT derived MLA of ≤5.38 mm2 strongly predicts the functional severity of a LM lesion. FUNDunding Acknowledgement Type of funding sources: None. Angiography and OCT image of LM stenosis ROC curves of MLA, MLD and AS

ANATOMY AND DRYING OF WOOD OF FOUR SPECIES FROM AN AGROFORESTRY SYSTEM

Drying is an important process in the generation of wood products, as it increases the quality of the final products; however, it is influenced by various anatomical characteristics. The aim of this study was to evaluate the influence of anatomy on the drying of wood of Parapiptadenia rigida (Benth.) Brenan, Peltophorum dubium (Spreng.) Taub., Eucalyptus grandis W. Hill × Eucalyptus urophylla S.T. Blake (hybrid), and Schizolobium parahyba (Vell.) Blake trees from an agroforestry system. Three trees aged 9 years were sampled for each species. The trees were removed from the study region when their diameter at breast height (DBH) was 1.30 m from the ground. Blocks were made with dimensions of 5.0 × 5.0 × 15.0 cm for the evaluation of oven drying and 1.5 × 1.5 × 2.0 cm for anatomical features. S. parahyba has the highest value of fiber diameter (35.1 µm) and lumen diameter (27.6 µm), whereas P. dubium had the highest value of cell wall thickness (6.8 µm). The average equilibrium moisture content was 10.98% after 40 days of drying. The anatomy of the wood influenced the drying of the four species intensity, which was related to humidity during all periods. The anatomical parameters that most influenced drying were fiber diameter (Pearson correlation coefficient: 0.77), lumen diameter (0.76), and fiber cell wall thickness (0.73); the higher the values, the greater was the drying intensity.