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Forests ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 107
Author(s):  
Wenbo Zhang ◽  
Tao Hu ◽  
Yanting Chang ◽  
Benhua Fei ◽  
Yanjun Ma ◽  
...  

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.


2022 ◽  
Author(s):  
Kristina Seftigen ◽  
Marina V. Fonti ◽  
Brian Luckman ◽  
Miloš Rydval ◽  
Petter Stridbeck ◽  
...  

Abstract. The continuous development of new proxies as well as a refinement of existing tools are key to advances in paleoclimate research and improvements in the accuracy of existing climate reconstructions. Herein, we build on recent methodological progress in dendroanatomy – the analyses of wood anatomical parameters in dated tree rings – and introduce the longest (1585–2014 CE) dendroanatomical dataset currently developed for North America. We explore the potential of dendroanatomy of high-elevation Engelmann spruce (Picea engelmannii) as a proxy of past temperatures by measuring anatomical cell dimensions of 15 living trees from the Columbia Icefield area. There, X-ray maximum latewood density (MXD) and its blue intensity counterpart (MXBI) have previously been measured, which allows comparing the different parameters. Our findings highlight anatomical MXD and maximum radial cell wall thickness as the two most promising wood anatomical proxy parameters for past temperatures, each explaining 46 % and 49 %, respectively, of instrumental, high-pass filtered, July–August maximum temperatures over the 1901–1994 period. While both parameters display comparable climatic imprinting at higher frequencies to X-ray derived MXD, the anatomical dataset distinguishes itself from its predecessors by providing the most temporally stable warm-season temperature signal. For the long-term secular trends, discrepancies between anatomical MXD and maximum radial cell wall thickness chronologies were observed, where the former more closely follow the long-term variations of the X-ray based MXD. Further studies, including samples from more diverse age cohorts and the adaptation of RCS-based standardizations, are needed to disentangle the ontogenetic and climatic components of long-term signals stored in the wood anatomical traits and to more comprehensively evaluate the potential contribution of this new dataset to paleoclimate research.


2022 ◽  
Vol 12 (2) ◽  
pp. 676
Author(s):  
Ladislav Morovic ◽  
Michaela Kritikos ◽  
Daynier Rolando Delgado Sobrino ◽  
Jozef Bilik ◽  
Robert Sobota ◽  
...  

Cold tube drawing provides higher accuracy compared to hot approaches. The process can be used to reduce the dimensions of tubes, and depending on the reduction size, the wall thickness of these may be subject to changes. In the process, any form of variability provoked by external factors is highly sensitive, given that the resulting tubes are often the final step in tube production. This paper focused on the evaluation of the influence of pre-tube factors on key variables after the drawing process, i.e., the final roundness, outer diameter, and wall thickness of the tubes. For these purposes, a factorial design with fixed factors was implemented. It was also a goal to investigate if the single-pass type of drawing would guarantee good statistical results potentially leading to significant time and financial reductions. The measurements were executed in the machine ZEISS CenterMax. The statistical analysis took place on Minitab 19. The results prove that most factors, and their interactions, significantly impacted the response variables, leading the authors to understand that a single-pass approach would not properly work under the conditions defined for the experimentation. These results also allow for reflection on the causes and necessary measures related to lubrication, technological heritage, and quality that would impact the results themselves.


Author(s):  
Olga Beatrice Carcassi ◽  
Guillaume Habert ◽  
Laura Elisabetta Malighetti ◽  
Francesco Pittau

The climate crisis is urging us to act fast. Buildings are a key leverage point to reduce greenhouse gas (GHG) emissions, but the embodied emissions related with their construction remain often the hidden challenge of any ambitious policy. Considering that a complete material substitution is not possible, we explore in this paper a material GHG compensation where fast-growing bio-based insulation materials are used to compensate building elements that necessarily release GHG. Looking for analogies with other human activities, different material diets as well as different building typologies are modelled to assess the consequences in term of bio-based insulation requirement to reach climate-neutrality. The material diets are defined according to the gradual use of herbaceous materials, from the insulation up to the structural level: omnivorous, vegetarian and vegan. Our results show the relationship in terms of volume between the climate intensive materials and the climate-negative ones needed to neutralize the overall building GHG emissions. Moreover, they suggest how climate-neutral building can look like and that it is possible to have climate-neutral buildings with wall thickness within the range of current construction practices.


Author(s):  
Budi Arief Waskito ◽  
Djanggan Sargowo ◽  
Umi Kalsum ◽  
Askandar Tjokroprawiro

Abstract Objectives Cardiovascular diseases, especially atherosclerosis, are the leading cause of human mortality in Indonesia. Ipomoea batatas (L.) is a food plant used in Indonesian traditional medicine to treat cardiovascular diseases and related conditions. We assessed the anti-atherosclerotic activity of the aqueous extract of I. batatas leaves in a rat model of high-fat diet-induced atherosclerosis and its mechanism. Methods The presence of amino acid content in the I. batatas L. purple variant was determined by liquid chromatography high-resolution mass spectrometry (LC-HRMS). Thirty male Wistar rats were divided into five groups (n=6/group), i.e., standard diet group (SD), high-fat diet group (HF), and HF plus I. batatas L. extracts orally (625; 1,250; or 2,500 mg/kg) groups. The numbers of macrophages and aortic wall thickness were analyzed histologically. Immunohistochemical analyses were performed to assess foam cells-oxidized low-density lipoprotein (oxLDL), endothelial nitric oxide synthase (eNOS), and vascular endothelial growth factor (VEGF) expression in the aorta. Results LC-HRMS analysis showed nine amino acid content were identified from I. batatas L. In vivo study revealed that oral administration of I. batatas L. leaf extract alleviated foam cells-oxLDL formation and aortic wall thickness caused by high-fat diet atherosclerosis rats. Further, I. batatas L. leaf extract promoted the number of macrophages and modulated VEGF and eNOS expression in the aorta. Conclusions I. batatas L. leaf extract shows a positive anti-atherosclerosis effect. Furthermore, the mechanism may promote the macrophages, eNOS, VEGF expressions, and inhibition of foam cells-oxLDL formation and aortic wall thickness with the best dosage at 2,500 mg/kg. This could represent a novel approach to prevent cardiovascular diseases.


Author(s):  
Takahiro Sakamoto ◽  
Kazuhiko Uchida ◽  
Akihiro Endo ◽  
Hiroyuki Yoshitomi ◽  
Kazuaki Tanabe

2022 ◽  
Vol 3 (1) ◽  
pp. 44-52
Author(s):  
Valeriu ESANU ◽  
Ina PALII

Introduction. Deterioration of left ventricular (LV) parameters in Diabetes Mellitus (DM) can occur in the absence of other heart problems. An association between glycosylated hemoglobin (HbA1c) and changes of the LV parameters in DM has been reported. However, data regarding this association model in children with Type 1 Diabetes Mellitus (T1DM) are limited. The purpose of the work was to investigate the association between HbA1c and the LV parameters in pediatric patients. Material and methods. The study was conducted on 28 children with T1DM ((aged 10 - 18 years, gender M (15)/F (13), duration ≥5 years). The clinical (standard medical examination) and paraclinical (biochemical dosage – HbA1c, echocardiography – LV functional and structural parameters) data was carried out. Statistical analysis  used the SPSS version 20. Results. The correlational study between the HbA1c and the LV parameters revealed a statistically significant positive correlation coefficient with aortic root diameter (mm) (r=0.7**, p<0.001), left atrium (mm) (r=0.8**, p<0.001 LV diastolic diameter (mm) (r=0.7**, p<0.001), LV systolic diameter (mm) (r=0.7**, p<0.001), septal wall thickness (mm) (r=0.5*, p=0.036), posterior wall thickness (mm) (r=0.5*, p=0.032), LV diastolic volume (ml) (r=0.5*, p=0.025), LV systolic volume (ml) (r=0.6**, p=0.01), ejection fraction (%) (r=0.7**, p=0.001), fractional shortening (%) (r=0.6**, p=0.002). Conclusions. The results of the study show that in children with T1DM, the increase value of the HbA1c is associated with a consensual and proportional increase in the values of the parameters of the left ventricle.  


Author(s):  
Yu-Jun Chen ◽  
Bai-Li Chen ◽  
Mei-Juan Liang ◽  
Shu-Ling Chen ◽  
Xue-Hua Li ◽  
...  

Abstract Background Early changes in bowel behavior during anti-TNF induction therapy in Crohn’s disease (CD) are relatively unknown. We determined (a) onset of changes in bowel behavior in CD patients receiving anti-TNF therapy by ultrasound; and (b) the feasibility of shear wave elastography (SWE) in predicting early response to anti-TNF therapy. Methods Consecutive ileal/ileocolonic CD patients programmed to initiate anti-TNF therapy were enrolled. Bowel ultrasound was performed at baseline, and at weeks 2, 6, and 14. Changes in bowel wall thickness, Doppler signals of the bowel wall (Limberg score), and SWE values were compared using a linear mixed model. Early response to anti-TNF therapy was based on a composite strategy of clinical and colonoscopy assessment at week 14. Results Of the 30 patients enrolled in this study, 20 patients achieved a response to anti-TNF therapy at week 14. The bowel wall thickness and SWE value of the response group showed a significant downward trend compared with the non-response group (P=0.003, P=0.011). Bowel wall thickness, the Limberg score, and SWE values were significantly reduced as early as week 2 compared with baseline (P&lt;0.001, P&lt;0.001, P=0.003) in the response group. Baseline SWE values (21.3±8.7 vs. 15.3±4.7 kPa, P=0.022) and bowel wall thickness (8.5±2.3 vs. 6.9±1.5 mm, P=0.027) in the non-response group were significantly higher than in the response group. Conclusions This pilot study suggested that changes in bowel ultrasound behavior could be assessed as early as week 2 after starting anti-TNF therapy. Bowel ultrasound together with elasticity imaging could predict early response to anti-TNF therapy.


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