total cross sectional area
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Author(s):  
EP Golubinskaya ◽  
TP Sataieva ◽  
II Fomochkina ◽  
AV Kubyshkin ◽  
TP Makalish ◽  
...  

Tumor-associated macrophages are able to regulate the tumor cell proliferation and to affect the tumor cell dissemination. The study was aimed to assess the predictive potential of the macrophage population immunohistochemical phenotyping in early malignization of H. pylori-associated chronic gastritis. Gastic biopsy samples of male and female patients aged 48 ± 7.2 infected with Helicobacter pylori were used as the research material. The patients were divided into three groups: non-atrophic chronic gastritis (NACG, n = 10), atrophic chronic gastritis (ACG, n = 10), G1/G2 gastric adenocarcinoma (GAC, n = 10). The macrophage population was visualized using the CD68 pan-macrophage marker and the type 2 monocyte/macrophage marker CD163. Intensity of neoangiogenesis was defined using the CD31 endothelial marker by assessing the total cross sectional area of blood vessels. It was found that chronic gastritis was accompanied by the dynamic increase in the size of the general macrophage population with the progression of atrophic and metaplastic processes. According to immunohistochemical study of biopsies obtained from patients with NCG, the CD163 : CD68 ratio was 0.67 ± 0.02, and the total cross sectional area of blood vessels was 3590.92 ± 356.27 µm2. Atrophic gastritis and adenocarcinoma were characterized by vector redistribution of monocytes/macrophages into the 2nd functional phenotype. The CD163 : CD68 expression index in the group with ACG was 0.81 ± 0.04, and in the group with GAC it was 0.88 ± 0.03. Microvascular area was significantly increased in the groups with ACG and GAC, which reflected tumor neoangiogenesis intensification under the influence of М2 monocytes/macrophages. The increased expression of CD163 can serve as a predictor of chronic gastritis malignization together with evaluation of the glandular epithelium atrophy and metaplasia degree.


2021 ◽  
Vol 27 (1) ◽  
pp. 97-106
Author(s):  
Hakas Prayuda

Prestressed concrete has been widely used in structural buildings, especially for big span length purposes. The prestressed concrete dimension cross sections normally are fixed, provided by the factory based on their experience for every span length. However, this size aspect can be developed to make better improvement. In this study, I and box girder shapes were modified with the same total cross-sectional area. Three types of modification have been made for each girder shape by giving the space on the middle for I girder and changing form from trapezoidal to rectangular section for box girder. The number of steel tendons for this research was made typically and same so that the stress and displacement can be compared fairly. Manual calculation was performed for all samples and was completed under three circumstances namely initial condition, loading condition, and final condition. Also, the manual calculation is according to Indonesian provisions, which are SNI 2833-2016 for the earthquake load and SNI 1725-2016 for normal loading on bridges. From the result, it is known that one shape for each girder shape has met the criteria for the smallest stress and displacement.


2021 ◽  
Vol 10 (3) ◽  
pp. e26710313204
Author(s):  
Paula Gomes Rodrigues ◽  
Katia de Oliveira ◽  
Stéphanie de Souza Vitório Alves ◽  
Camila Fernada Fidêncio ◽  
Clístenes Gomes de Oliveira ◽  
...  

Physical activities frequency and intensity performed by equine, athletes or workers, have been growing significantly enabling appearance of musculoskeletal disorders. Thus, the objective of this research was to evaluate the effect of a functional training program to measure short-, medium- and long-term response on epaxial musculature development, as well in linear kinematics of patrol horses. Eight 14±3.5 years-old horses, weighing 418±50 kg, were evaluated over a 90 days period to divided in short (30 days), medium (60 days) and long (90 days) responses. All horses were submitted to the same FTP consisting of passive stretching exercises, dynamic mobilization, reflexive mobilization and dynamic imbalance. The monitored traits were the Longissimus dorsi (LD) muscle thickness; the Musculus multifidus (MM) total cross-sectional muscle area; linear kinematic analysis through the stride length at walk (LSW) and trot (LST). The thickness of the right and left side-LD showed increase at 90-day of the training period. The MM total cross-sectional area increased progressively after 30 days on both sides of the body, and at end of the 90-day evaluation. LSW and LST increased after 60 days of training. It is concluded for short-term; exercises promoted the hypertrophy of Musculus multifidus; for medium-term, increased the stride length and, and for long-term, hypertrophy of the Longissimus dorsi was observed.


PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0244633
Author(s):  
J. R. Cooley ◽  
J. J. Hebert ◽  
A. de Zoete ◽  
T. S. Jensen ◽  
P. R. Algra ◽  
...  

Purpose Studies using magnetic resonance imaging to assess lumbar multifidus cross-sectional area frequently utilize T1 or T2-weighted sequences, but seldom provide the rationale for their sequence choice. However, technical considerations between their acquisition protocols could impact on the ability to assess lumbar multifidus anatomy or its fat/muscle distinction. Our objectives were to examine the concurrent validity of lumbar multifidus morphology measures of T2 compared to T1-weighted sequences, and to assess the reliability of repeated lumbar multifidus measures. Methods The lumbar multifidus total cross-sectional area of 45 patients was measured bilaterally at L4 and L5, with histogram analysis determining the muscle/fat threshold values per muscle. Images were later re-randomized and re-assessed for intra-rater reliability. Matched images were visually rated for consistency of outlining between both image sequences. Bland-Altman bias, limits of agreement, and plots were calculated for differences in total cross-sectional area and percentage fat between and within sequences, and intra-rater reliability analysed. Results T1-weighted total cross-sectional area measures were systematically larger than T2 (0.2 cm2), with limits of agreement <±10% at both spinal levels. For percentage fat, no systematic bias occurred, but limits of agreement approached ±15%. Visually, muscle outlining was consistent between sequences, with substantial mismatches occurring in <5% of cases. Intra-rater reliability was excellent (ICC: 0.981–0.998); with bias and limits of agreement less than 1% and ±5%, respectively. Conclusion Total cross-sectional area measures and outlining of muscle boundaries were consistent between sequences, and intra-rater reliability for total cross-sectional area and percentage fat was high indicating that either MRI sequence could be used interchangeably for this purpose. However, further studies comparing the accuracy of various methods for distinguishing fat from muscle are recommended.


2020 ◽  
Vol 9 (24) ◽  
Author(s):  
Gregory T. Adamson ◽  
Doff B. McElhinney ◽  
Yulin Zhang ◽  
Jeffrey A. Feinstein ◽  
Lynn F. Peng ◽  
...  

Background Due in part to the heterogeneity of the pulmonary circulation in patients with tetralogy of Fallot and major aortopulmonary collateral arteries (MAPCAs), research on this condition has focused on relatively basic anatomic characteristics. We aimed to detail pulmonary artery (PA) and MAPCA anatomy in a large group of infants, assess relationships between anatomy and early surgical outcomes, and consider systems for classifying MAPCAs. Methods and Results All infants ( <1 year of age) undergoing first cardiac surgery for tetralogy of Fallot/MAPCAs from 2001 to 2019 at Stanford University were identified. Preoperative angiograms delineating supply to all 18 pulmonary segments were reviewed for details of each MAPCA and the arborization and size of central PAs. We studied 276 patients with 1068 MAPCAs and the following PA patterns: 152 (55%) incompletely arborizing PAs, 48 (17%) normally arborizing PAs, 45 (16%) absent PAs, and 31 (11%) unilateral MAPCAs. There was extensive anatomic variability, but no difference in early outcomes according to PA arborization or the predominance of PAs or MAPCAs. Patients with low total MAPCA and/or PA cross‐sectional area were less likely to undergo complete repair. Conclusions MAPCA anatomy is highly variable and essentially unique for each patient. Though each pulmonary segment can be supplied by a MAPCA, central PA, or both, all anatomic combinations are similarly conducive to a good repair. Total cross‐sectional area of central PA and MAPCA material is an important driver of outcome. We elucidate a number of novel associations between anatomic features, but the extreme variability of the pulmonary circulation makes a granular tetralogy of Fallot/MAPCA classification system unrealistic.


Author(s):  
Anthony L. Smith ◽  
Wonhee Kim ◽  
Jeffrey Brown

Abstract Automotive grille shutters are used to reduce the aerodynamic drag of the vehicle when cooling requirements are low by blocking a portion of the airflow through the condenser, radiator, and fan module (CRFM); the lower aerodynamic drag improves fuel economy. A passively actuated SMA grille shutter was designed as a less complex and lower overall cost solution to current electro-mechanical designs. This paper presents the design and calibration process for the automotive grille shutter SMA actuator using passive temperature control. The initial design target opening and closing temperatures of the grille shutter system were determined by climatic wind tunnel and vehicle road tests measuring motor-driven grille shutter position versus CRFM exhaust temperature. The initial SMA actuator design almost met the temperature requirements; subsequent road testing confirmed the need to shift the start to close and fully closed temperatures at least 6 °C higher to meet specifications. The transformation temperatures of the SMA actuator were calibrated by varying stress on the SMA wires by means of the total cross-sectional area and biasing force. Tests were performed in an environmental chamber to characterize the temperature-position behavior during heating and cooling cycles, the best candidate improved the hysteresis band by 3 °C from the initial design. This study presents an industry need for the development of lower hysteresis SMA wires/springs for passive applications, which can maximize the benefit of SMA actuation by utilizing the temperature-stress-strain coupling behavior of SMA.


Energies ◽  
2020 ◽  
Vol 13 (14) ◽  
pp. 3512 ◽  
Author(s):  
Vasileios Kitsikoudis ◽  
Pierre Archambeau ◽  
Benjamin Dewals ◽  
Estanislao Pujades ◽  
Philippe Orban ◽  
...  

The intermittent nature of most renewable energy sources requires their coupling with an energy storage system, with pumped storage hydropower (PSH) being one popular option. However, PSH cannot always be constructed due to topographic, environmental, and societal constraints, among others. Underground pumped storage hydropower (UPSH) has recently gained popularity as a viable alternative and may utilize abandoned mines for the construction of the lower reservoir in the underground. Such underground mines may have complex geometries and the injection/pumping of large volumes of water with high discharge could lead to uneven water level distribution over the underground reservoir subparts. This can temporarily influence the head difference between the upper and lower reservoirs of the UPSH, thus affecting the efficiency of the plant or inducing structural stability problems. The present study considers an abandoned slate mine in Martelange in Southeast Belgium as the lower, underground, reservoir of an UPSH plant and analyzes its hydraulic behavior. The abandoned slate mine consists of nine large chambers with a total volume of about 550,000 m3, whereas the maximum pumping and turbining discharges are 22.2 m3/s. The chambers have different size and they are interconnected with small galleries with limited discharge capacity that may hinder the flow exchange between adjacent chambers. The objective of this study is to quantify the effect of the connecting galleries cross-section and the chambers adequate aeration on the water level variations in the underground reservoir, considering a possible operation scenario build upon current electricity prices and using an original hydraulic modelling approach. The results highlight the importance of adequate ventilation of the chambers in order to reach the same equilibrium water level across all communicating chambers. For fully aerated chambers, the connecting galleries should have a total cross-sectional area of at least 15 m2 to allow water flow through them without significant restrictions and maintain similar water level at all times. Partially aerated chambers do not attain the same water level because of the entrapped air; however, the maximum water level differences between adjacent chambers remain relatively invariant when the total cross-sectional area of the connecting galleries is greater than 8 m2. The variation of hydraulic roughness of the connecting galleries affects the water exchange through small connecting galleries but is not very influential on water moving through galleries with large cross-sections.


2020 ◽  
Vol 9 (7) ◽  
pp. 617-626
Author(s):  
Ya-Fen Hu ◽  
Lin Hua ◽  
Xiu Tuo ◽  
Ting-Ting Shi ◽  
Yi-Lin Yang ◽  
...  

Background The pathogenesis underlying the alterations of orbital architecture in Graves’ orbitopathy (GO) is not yet fully understood. The present study aimed to investigate the association of DNA methylation in peripheral blood and orbital volumetry in Chinese patients with GO. Methods A total of 35 GO subjects (70 orbits) were subjected to CT scan. The total cross-sectional area of the extraocular muscles (orbital muscles, OM), total orbit area (TOA), and the exophthalmometry were measured and OM/TOA ratio was calculated. Targeted bisulfite sequencing was performed on seven candidate genes. Results No significant correlation was established between the DNA methylation levels of these genes and exophthalmometry. The MBP methylation level was found to be correlated with OM/TOA ratio (P < 0.05). Multiple linear regression analysis on parameters including age, sex, TRAb, duration of GO, and DNA methylation levels of seven genes with OM/TOA ratio confirmed that MBP and OM/TOA ratio had a significant correlation (P < 0.05). The partial least squares analysis showed that the top three genes with the highest loadings were MBP, BOLL, and BECN1 and that OM/TOA ratio affected the DNA methylation block than exophthalmometry. Conclusions This study provided preliminary evidence that MBP is a potential gene associated with OM enlargement in GO patients according to the combination of DNA methylation sequencing and orbital CT measurement.


Author(s):  
М. Г. Залюбовський ◽  
І. В. Панасюк ◽  
В. В. Малишев

Experimental determination of the energy and the number of impact interactions with the solid supporting surface of the castings of the «zipper» lock necessary to separate parts from the gate. Getting the corresponding calculated dependencies. Experimental modeling of impact interaction of metal parts of the “zipper” lock with the surface of the working capacity by falling castings of parts from different heights with their further collision with the supporting surface. Based on the conducted experimental study, mathematical dependences are obtained that allow one to evaluate the effect of changes in mechanical energy on the intensity of separation of metal parts of the lightning lock from the gate. In particular, it was found that with an increase in mechanical energy during the fall of castings, the intensity of separation of metal parts from gates increases significantly. The relationship between the kinetic energy needed to separate the parts of the castings of the “zipper” lock at the moment of collision with a solid surface and the total cross-sectional area of the gating system is established. The relationship between the number of shock interactions of castings of the “zipper” lock with a solid surface, necessary for separating parts, the interaction energy and the casting parameters, is determined. The obtained mathematical dependences for calculating the number of shock interactions of castings of the “zipper” lock necessary to separate all parts from the gate system of the corresponding type when falling from any chosen height. These dependencies can be used to carry out further research, in particular, to rationally determine the time spent on performing these technological operations.


2019 ◽  
Author(s):  
Jeffrey Cooley ◽  
Jeffrey Hebert ◽  
Annemarie de Zoete ◽  
Tue Jensen ◽  
Paul Algra ◽  
...  

Abstract Background: Studies using magnetic resonance imaging to assess lumbar multifidus cross-sectional area frequently utilize T1 or T2-weighted sequences, but seldom provide the rationale for their sequence choice. However, technical considerations between their acquisition protocols could impact on the ability to assess lumbar multifidus anatomy or its fat/muscle distinction. Our objectives were to examine the concurrent validity of lumbar multifidus morphology measures of T2 compared to T1-weighted sequences, and to assess the reliability of repeated lumbar multifidus measures. Methods: The lumbar multifidus total cross-sectional area from 360 muscles was measured bilaterally at L4 and L5, with histogram analysis determining the muscle/fat threshold values per muscle. Images were later re-randomized and re-assessed for intra-rater reliability. Matched images were visually rated for consistency of outlining between both image sequences. Bland-Altman bias, limits of agreement, and plots were calculated for differences in total cross-sectional area and percentage fat between and within sequences, and intra-rater reliability analysed. Results: T1-weighted total cross-sectional area measures were systematically larger than T2 (0.2 cm2), with limits of agreement <±10% at both spinal levels. For percentage fat, no systematic bias occurred, but limits of agreement approached ±15%. Visually, muscle outlining was consistent between sequences, with substantial mismatches occurring in <5% of cases. Intra-rater reliability was excellent (ICC: 0.981 – 0.998); with bias and limits of agreement less than 1% and ±5%, respectively. Conclusion: Total cross-sectional area measures and outlining of muscle boundaries were consistent between sequences, and intra-rater reliability for total cross-sectional area and percentage fat was high indicating that either MRI sequence could be used interchangeably for this purpose. However, further studies comparing the accuracy of various methods for distinguishing fat from muscle are recommended.


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