Journal articles on the topic 'Undulation index'
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1
Kropáč, O., and P. Múčka. "Longitudinal road unevenness with periodic components: Characterization and effects on people in a traversing vehicle and the loading of the pavement." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 219, no. 6 (June 1, 2005): 773–90. http://dx.doi.org/10.1243/095440705x28394.
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Firstly, the effect of periodic components (undulation) appearing in the otherwise random longitudinal profile of road on standard indicators of random unevenness is studied. The power spectral density characterized by its parameters, i.e. the unevenness index and waviness, three band variances, and international roughness index are considered. Secondly, a series of simulation examples is given of the response of two planar vehicle models (a passenger car and a truck) traversing along the road with periodic components of longitudinal unevenness. The effects on people sitting in the vehicle and on the loading of the vehicle undercarriage and pavement structure are studied. The wavelengths of undulation and the running speeds that appear as most inconvenient are emphasized
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Thannoun, Rayan. "Three Dimensional Terrain Modeling for Tectonic Geomorphology of Chinara Anticline, Northern Iraq." Iraqi Geological Journal 54, no. 1C (March 31, 2021): 53–65. http://dx.doi.org/10.46717/igj.54.1c.5ms-2021-03-25.
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Analysis of the terrain using three-dimensional models offers a deep insight view of ground surface topography and terrain representation. The Chinara anticline is one of the main structures of NW-SE trends for the highly folded zone in northeastern Iraq. The objective of this study is to understand the interrelationship between topography and morphotectonic features using three-dimensional models. This research employed fourth generates principal raster derivative products from the DEM using ArcGIS. To understand the undulating of this anticline with the morphotectonic style, the adaptive equation has been suggested to determine the direction and amount of the main tectonic forces, which can be applied to other undulated anticlines. The values of northeastern and southwestern limbs undulating index UI are 11.7 and 7.8 respectively that indicates the strong tectonic force towards the northeast. Two listric faults have been conducted via the field survey that confirmed by remotely sensed interpretation and DEM products. These listric faults had an intensive impact in comparison with concluded strike-slip faults, and then the Chinara anticline would be less structural undulating in a region of vicinity syncline to Perat undulation. The morphotectonic landscapes reveal that the listric fault has branched into two parts, the first one extending to form the anticline and the other comprises the structural dilemma.
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Omri, Mohamed, Muhammad Jamal, Shafqat Hussain, Lioua Kolsi, and Chemseddine Maatki. "Conjugate Natural Convection of a Hybrid Nanofluid in a Cavity Filled with Porous and Non-Newtonian Layers: The Impact of the Power Law Index." Mathematics 10, no. 12 (June 13, 2022): 2044. http://dx.doi.org/10.3390/math10122044.
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This study deals with the effect of the power law index on the convective heat transfer of hybrid nanofluids in a square cavity divided into three layers. The effect of a solid fluid layer is also given attention. A two-dimensional system of partial differential equations is discretized by using the generalized finite element method (FEM). A FEM having cubic polynomials (P3) is employed to approximate the temperature and velocity components, whereas the pressure is approached using quadratic finite element functions. The discretized set of equations have been solved using Newton’s method. The numerical code which is used in this study has been validated by comparing with experimental findings. Mathematical simulations are performed for different sets of parameters, including the Rayleigh number (between 103 and 106), the power law index (between 0.6 to 1.8), Darcy number (between 10−6 to 10−2), undulation (between 1 and 5) and the thermal conductivity ratio (between 0.1 and 10). The results infer that a remarkable penetration of streamlines is figured out towards the porous hybrid layer as the power law index is increased. The average Nu increases with increasing Ra, and the maximum value is noted at Ra=106. There is no much alteration observed for isotherms at the solid layer by increasing Da. The average Nu decreases by increasing the undulations. The rate of heat transfer is enhanced at the heated boundary and solid fluid interface of the cavity by raising the ratio of thermal conductivity.
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Colip, Charles G., Sean Wo, Daniel S. Hippe, Hiroko Watase, Alfonso R. Urdaneta-Moncada, Chengcheng Zhu, Lei Wu, et al. "Computed tomography angiography findings predictive of post-intervention vasospasm in patients with aneurysmal subarachnoid hemorrhage." British Journal of Radiology 94, no. 1121 (May 1, 2021): 20200893. http://dx.doi.org/10.1259/bjr.20200893.
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Objective: To evaluate the association of CT/CT angiography (CTA) findings and clinical characteristics with subsequent vasospasm in patients with aneurysmal subarachnoid hemorrhage (aSAH). Methods-: Consecutive presentation CTA head exams in patients with aSAH between January 2005 and June 2015 were retrospectively evaluated for intracranial arterial calcification, undulation and non-calcified stenosis. Additional variables including modified Fisher Scale (mFS), Glasgow Coma Scale (GCS) and neurological exam status were reviewed. Associations of CTA findings with the incidence of angiographic vasospasm were assessed with multivariate logistic regression models using the least absolute shrinkage and selection operator machine-learning algorithm. Model performance was summarized using c-index with bootstrap optimism-adjustment. Results Intracranial arterial calcification, seen in 51.7% of 195 total patients, was protective against vasospasm (OR-0.6; 95% CI-0.52–0.67; p = 0.009), while arterial undulation (24%) was associated with subsequent vasospasm (OR-2.6; 95% CI-1.3–5.1; p = 0.007). Non-calcified intracranial arterial stenosis (5%) was associated with subsequent vasospasm, (OR-4.7; 95% CI-1.0–22.8; p = 0.054). Least absolute shrinkage and selection operator selected all three CTA findings as predictors in a multivariate model for vasospasm in addition to clinical factors, which demonstrated superior predictive performance (c-index-0.74; 95% CI-0.69–0.82) compared to a model based on mFS and clinical factors only (c-index-0.66; 95% CI-0.57–0.75; p = 0.010 for the difference). Conclusion: Presentation CTA findings combined with clinical factors may better predict the development of vasospasm in patients with aSAH compared to current prognostic models alone. Advances in knowledge: The combination of initial CT/CTA and clinical findings better predict development of vasospasm after aSAH. This can lead to better markers for use in future clinical trials to develop vasospasm preventative treatments and potentially provide better targets for early aggressive treatment.
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Sun, Yong Jun, and Yi Qu. "Study on the Maintenance Capacity of “Man-Machine System” Based on Fuzzy Comprehensive Evaluation." Applied Mechanics and Materials 203 (October 2012): 479–83. http://dx.doi.org/10.4028/www.scientific.net/amm.203.479.
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This paper, in accordance with the maintenance capacity of “Man-Machine System”, holds the core of the “Man-Machine System” and employs the analysis methods of the complex system, brings forward the model of the three-layer comprehensive evaluation based on fuzzy mathematics, then brings out the methods of the index weight and studies the maintenance capacity’s evaluation algorithm on the foundation of the quantitative analysis. In the last it gives the application of the model and algorithm by using the instances and studies the changing maintenance capacity including the stability and the undulation, which provides one thought for scientifically evaluating the maintenance capacity of “Man-Machine System”.
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Conceição, Ana, António J. Silva, José Boaventura, Daniel A. Marinho, and Hugo Louro. "Wave Characteristics in Breaststroke Technique with and Without Snorkel Use." Journal of Human Kinetics 39, no. 1 (December 1, 2013): 185–94. http://dx.doi.org/10.2478/hukin-2013-0081.
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Abstract The purpose of this paper was to examine the characteristics of waves generated when swimming with and without the use of Aquatrainer® snorkels. Eight male swimmers performed two maximal bouts of 25 m breaststroke, first without the use of a snorkel (normal condition) and then using a snorkel (snorkel condition). The body landmarks, centre of the mass velocity, stroke rate, stroke length, stroke index, and Strouhal number (St) were quantified. Fourier analysis was conducted to determine the frequency, amplitude, and phase characteristics of the vertical undulations. We also determined the undulation period, the first and second harmonic wave percentage, and the contribution of these components to the power of each of the wave signals. The first wave harmonics had a frequency of 0.76 Hz (normal condition) and 0.78 Hz (snorkel condition), and the second wave harmonics had a frequency of 1.52 Hz (normal condition) and 1.56 Hz (snorkel condition). Under the normal conditions, the wave amplitude was higher on the vertex (0.72 m) and cervical (0.32 m) than that produced under snorkel conditions (0.71 m and 0.28 m, respectively). The lowest values were found in the hip (0.03 m in normal conditions, and 0.02 m in snorkel conditions) and in the trunk (0.06 m in normal conditions, and 0.04 m in snorkel conditions). It can be concluded that snorkel use seems to lead to slight changes in the biomechanical pattern in swimming velocity, as well as several stroke mechanical variables.
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Tsai, Ming Chang, and Shyh Chour Huang. "The Analysis of Pulse Pressure by Vascular Strain." Applied Mechanics and Materials 256-259 (December 2012): 2383–86. http://dx.doi.org/10.4028/www.scientific.net/amm.256-259.2383.
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The objective of this paper is to use the Noninvasive Strain Measurement System to monitor the pulse pressure of the blood’s undulation in the artery as an index for the clinical diagnosis of arteriosclerosis. In the study, a strain-measuring device (350Ω) is affixed to the left side of the radial styloid process, on the surface of the skin, and is connected to the Strain FleXense. An artery-pressuring tape is set on the left humerus, and the measurement of the wavelength and frequency of the heartbeat is taken to compare with the clinical artery wave. The results show that when the subject is in a comfortable position with moderate physiological levels, the heartbeat has no connection whatsoever with blood pressure. The greatest heartbeat strain, which occurs when the veins and arteries respectively are being cleared, displays as a linear change.
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Tsai, Ming Chang, and Shyh Chour Huang. "The Analysis of Pulse Pressure by Vascular Strain." Applied Mechanics and Materials 268-270 (December 2012): 1194–97. http://dx.doi.org/10.4028/www.scientific.net/amm.268-270.1194.
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The objective of this paper is to use the Noninvasive Strain Measurement System to monitor the pulse pressure of the blood’s undulation in the artery as an index for the clinical diagnosis of arteriosclerosis. In the study, a strain-measuring device (350Ω) is affixed to the left side of the radial styloid process, on the surface of the skin, and is connected to the Strain FleXense. An artery-pressuring tape is set on the left humerus, and the measurement of the wavelength and frequency of the heartbeat is taken to compare with the clinical artery wave. The results show that when the subject is in a comfortable position with moderate physiological levels, the heartbeat has no connection whatsoever with blood pressure. The greatest heartbeat strain, which occurs when the veins and arteries respectively are being cleared, displays as a linear change.
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Nakagawa, Daichi, Kohsuke Kudo, Olatilewa Awe, Mario Zanaty, Yasunori Nagahama, Cameron Cushing, Vincent Magnotta, et al. "Detection of microbleeds associated with sentinel headache using MRI quantitative susceptibility mapping: pilot study." Journal of Neurosurgery 130, no. 4 (April 2019): 1391–97. http://dx.doi.org/10.3171/2018.2.jns1884.
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OBJECTSentinel headaches (SHs) associated with cerebral aneurysms (CAs) could be due to microbleeds, which are considered a sign that an aneurysm is unstable. Despite the prognostic importance of these microbleeds, they remain difficult to detect using routine imaging studies. The objective of this pilot study is to detect microbleeds associated with SH using a magnetic resonance imaging (MRI) quantitative susceptibility mapping (QSM) sequence and then evaluate the morphological characteristics of unstable aneurysms with microbleeds.METHODSTwenty CAs in 16 consecutive patients with an initial presentation of headache (HA) leading to a diagnosis of CA were analyzed. Headaches in 4 of the patients (two of whom had 2 aneurysms each) met the typical definition of SH, and the other 12 patients (two of whom also had 2 aneurysms each) all had migraine HA. All patients underwent imaging with the MRI-QSM sequence. Two independent MRI experts who were blinded to the patients’ clinical history performed 3D graphical analysis to evaluate for potential microbleeds associated with these CAs. Computational flow and morphometric analyses were also performed to estimate wall shear and morphological variables.RESULTSIn the 4 patients with SH, MRI-QSM results were positive for 4 aneurysms, and hence these aneurysms were considered positive for non-heme ferric iron (microbleeds). The other 16 aneurysms were negative. Among aneurysm shape indices, the undulation index was significantly higher in the QSM-positive group than in the QSM-negative group. In addition, the spatial averaged wall shear magnitude was lower in the aneurysm wall in direct contact with microbleeds.CONCLUSIONSMRI-QSM allows for objective detection of microbleeds associated with SH and therefore identification of unstable CAs. CAs with slightly greater undulation indices are associated with positive MRI-QSM results and hence with microbleeds. Studies with larger populations are needed to confirm these preliminary findings.
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Ercan, Fabian E. Z., Juha Mikola, Tarja Silfver, Kristiina Myller, Elina Vainio, Sandra Słowińska, Michał Słowiński, Mariusz Lamentowicz, Daan Blok, and Friederike Wagner-Cremer. "Effects of experimental warming on Betula nana epidermal cell growth tested over its maximum climatological growth range." PLOS ONE 16, no. 5 (May 19, 2021): e0251625. http://dx.doi.org/10.1371/journal.pone.0251625.
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Numerous long-term, free-air plant growth facilities currently explore vegetation responses to the ongoing climate change in northern latitudes. Open top chamber (OTC) experiments as well as the experimental set-ups with active warming focus on many facets of plant growth and performance, but information on morphological alterations of plant cells is still scarce. Here we compare the effects of in-situ warming on leaf epidermal cell expansion in dwarf birch, Betula nana in Finland, Greenland, and Poland. The localities of the three in-situ warming experiments represent contrasting regions of B. nana distribution, with the sites in Finland and Greenland representing the current main distribution in low and high Arctic, respectively, and the continental site in Poland as a B. nana relict Holocene microrefugium. We quantified the epidermal cell lateral expansion by microscopic analysis of B. nana leaf cuticles. The leaves were produced in paired experimental treatment plots with either artificial warming or ambient temperature. At all localities, the leaves were collected in two years at the end of the growing season to facilitate between-site and within-site comparison. The measured parameters included the epidermal cell area and circumference, and using these, the degree of cell wall undulation was calculated as an Undulation Index (UI). We found enhanced leaf epidermal cell expansion under experimental warming, except for the extremely low temperature Greenland site where no significant difference occurred between the treatments. These results demonstrate a strong response of leaf growth at individual cell level to growing season temperature, but also suggest that in harsh conditions other environmental factors may limit this response. Our results provide evidence of the relevance of climate warming for plant leaf maturation and underpin the importance of studies covering large geographical scales.
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Шмыленко, Влада, Vlada Shmylenko, Альбина Бондаренко, Albina Bondarenko, Ольга Троценко, Olga Trotsenko, Вячеслав Туркутюков, and Vyacheslav Turkutyukov. "FREQUENCY OF DETECTION OF MORAXELLA CATARRHALIS IN CHILDREN WITH A RECURRENT COURSE OF RESPIRATORY DISEASES IN KHABAROVSK CITY DURING 2016-2017." Bulletin physiology and pathology of respiration 1, no. 68 (June 7, 2018): 52–56. http://dx.doi.org/10.12737/article_5b18b82fc43524.59761242.
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The aim of the study was to evaluate the Moraxella catarrhalis nasopharyngeal carriage prevalence in children of different age groups with a recurrent course of respiratory diseases and perform a comparative analysis of bacterial carriage levels as well as peculiarities of within-year distribution of nasopharyngeal carriage in 2016-2017 years. Bacteriological assessment was performed for 1769 children aged 0 to 14 years old including 1082 children examined in 2016 and 687 children examined in 2017. During the two years of observation the average level of M. catarrhalis carriage for the entire study group was equal to 11.5±0.76%. Nasopharyngeal carriage was detected in children of all age groups with the lowest index in children of 7-14 years (4.1±1.03%) and highest levels of bacterial carriage in children of 2-6 years old (13.8±0.98%). Similarities in distribution of M. catarrhalis nasopharyngeal carriage levels in susceptible age groups were detected during 2016 and 2017 years. The analysis of M. catarrhalis carriage levels dynamics revealed within-year undulation of the index – low levels were detected in February and July and high levels in October and November. The research revealed statistically significant and profound concordance of within-year distribution of M. catarrhalis carriage levels in children during 2016 and 2017 years.
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Duan, Guoli, Nan Lv, Jianhua Yin, Jinyu Xu, Bo Hong, Yi Xu, Jianmin Liu, and Qinghai Huang. "Morphological and hemodynamic analysis of posterior communicating artery aneurysms prone to rupture: a matched case–control study." Journal of NeuroInterventional Surgery 8, no. 1 (November 17, 2014): 47–51. http://dx.doi.org/10.1136/neurintsurg-2014-011450.
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ObjectivesWe evaluated the correlation between posterior communicating artery (PcomA) aneurysm rupture and morphological and hemodynamic parameters to assess related rupture risk indices.MethodsSix patients with PcomA aneurysms that ultimately ruptured (cases) were studied after initially being included in a prospective database including their three-dimensional (3D) imaging before rupture. For each case, four incidental stable unruptured aneurysms (controls) were randomly selected and matched based on clinical factors. The 3D images from all patients were reconstructed to establish the patient-specific model. Six morphologic parameters and three hemodynamic parameters were measured and calculated. A conditional logistic regression analysis was used to assess the individual risk of rupture.ResultsThe analysis demonstrated a larger aneurysm size (p=0.001), higher aspect ratio (p=0.018), ellipticity index (p<0.001), undulation index (p=0.005), percentage of low wall shear stress (WSS) area (LSA%) (p=0.010), and a lower normalized WSS (p=0.005) in the case group. The multivariate conditional logistic regression analysis demonstrated that only normalized WSS was significantly associated with the rupture of PcomA aneurysms (OR 0.151; 95% CI 0.025 to 0.914; p=0.040).ConclusionsHemodynamics and morphology are closely associated with aneurysm rupture, and WSS may be a more reliable parameter characterizing the rupture status of PcomA aneurysms.
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Lv, Nan, Ying Yu, Jinyu Xu, Christof Karmonik, Jianmin Liu, and Qinghai Huang. "Hemodynamic and morphological characteristics of unruptured posterior communicating artery aneurysms with oculomotor nerve palsy." Journal of Neurosurgery 125, no. 2 (August 2016): 264–68. http://dx.doi.org/10.3171/2015.6.jns15267.
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OBJECT Unruptured posterior communicating artery (PCoA) aneurysms with oculomotor nerve palsy (ONP) have a very high risk of rupture. This study investigated the hemodynamic and morphological characteristics of intracranial aneurysms with high rupture risk by analyzing PCoA aneurysms with ONP. METHODS Fourteen unruptured PCoA aneurysms with ONP, 33 ruptured PCoA aneurysms, and 21 asymptomatic unruptured PCoA aneurysms were included in this study. The clinical, morphological, and hemodynamic characteristics were compared among the different groups. RESULTS The clinical characteristics did not differ among the 3 groups (p > 0.05), whereas the morphological and hemodynamic analyses showed that size, aspect ratio, size ratio, undulation index, nonsphericity index, ellipticity index, normalized wall shear stress (WSS), and percentage of low WSS area differed significantly (p < 0.05) among the 3 groups. Furthermore, multiple comparisons revealed that these parameters differed significantly between the ONP group and the asymptomatic unruptured group and between the ruptured group and the asymptomatic unruptured group, except for size, which differed significantly only between the ONP group and the asymptomatic unruptured group (p = 0.0005). No morphological or hemodynamic parameters differed between the ONP group and the ruptured group. CONCLUSIONS Unruptured PCoA aneurysms with ONP demonstrated a distinctive morphological-hemodynamic pattern that was significantly different compared with asymptomatic unruptured PCoA aneurysms and was similar to ruptured PCoA aneurysms. The larger size, more irregular shape, and lower WSS might be related to the high rupture risk of PCoA aneurysms.
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Ding, Qing, Runqiu Huang, Fengyan Wang, Jianping Chen, Mingchang Wang, and Xuqing Zhang. "Multi-Parameter Dominant Grouping of Discontinuities in Rock Mass Using Improved ISODATA Algorithm." Mathematical Problems in Engineering 2018 (December 12, 2018): 1–10. http://dx.doi.org/10.1155/2018/5619404.
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The dominant grouping of the discontinuities in a rock mass is crucial to investigating the rock structure and stability. The traditional grouping methods are mostly based on the discontinuity orientation. However, other discontinuity parameters nonnegligibly impact the properties of a rock mass. If two discontinuities have the same orientation but differ otherwise, their mechanical and hydraulic properties would differ. In the present study, orientation, trace length, opening degree, and undulation of discontinuities were used to develop a multi-parameter dominant discontinuity grouping method that utilizes an improved ISODATA algorithm. The developed method uses several indicators, such as the weighted Euclidean distance and standard deviation, to iteratively update the clustering centers of the discontinuities. A clustering validity index was introduced for assessment and optimization of the discontinuity grouping results, and an adaptive grouping model that considers the weight of each grouping parameter was developed. By grouping discontinuities generated by Monte Carlo stochastic simulation, defects existing in the grouping based on the orientation only were illustrated, and the rationality of the established adaptive grouping model was verified. The engineering practicability of the method was further verified by using it to group discontinuities measured in the Dongsheng Quarry in Jingyuetan, Changchun, China.
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Leemans, Eva L., Bart M. W. Cornelissen, Miran Said, René van den Berg, Cornelis H. Slump, Henk A. Marquering, and Charles B. L. M. Majoie. "Intracranial aneurysm growth: consistency of morphological changes." Neurosurgical Focus 47, no. 1 (July 2019): E5. http://dx.doi.org/10.3171/2019.4.focus1987.
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OBJECTIVEPrevious studies have shown a relation between growth and rupture of intracranial aneurysms. Additionally, several morphological characteristics are frequently measured to estimate rupture risk. Little is known about how the rupture risk is associated with morphological characteristic changes during growth. The aim of this study was to provide insights into how morphological characteristics, associated with rupture, change during an aneurysm’s growth.METHODSThe authors retrospectively identified patients with longitudinal MRA images of unruptured growing aneurysms. The MRA images had an in-plane resolution of 0.2–0.5 mm and a slice thickness of 0.2–0.75 mm. Therefore, growth was defined as an increase of at least 0.5 mm in two directions or 1 mm in one direction. Using the MRA images, the authors semiautomatically segmented the aneurysm and the perianeurysmal vasculature. Twelve morphological characteristics were automatically measured. These characteristics were related to size (diameter, height, width, neck diameter, volume, surface area, aspect ratio, height-width ratio, and bottleneck factor) and shape (ellipticity index, nonsphericity index, and undulation index) of the aneurysm. Morphological characteristics before and after growth were compared using the Wilcoxon signed-rank test.RESULTSThe authors included 31 patients with 38 growing aneurysms. The aneurysms’ growth was detected after a mean of 218 weeks (range 23–567 weeks). A significant increase was seen in all size-related characteristics, and the bottleneck factor also significantly increased (from a median of 1.00 [IQR 0.85–1.04] to 1.03 [IQR 0.93–1.18]), while the ellipticity index decreased (from a median of 0.26 [IQR 0.25–0.28] to 0.25 [IQR 0.24–0.26]). The changes in size ratios and shape indices varied largely among patients. Larger aneurysms more often showed an increase in shape ratios.CONCLUSIONSAlthough aneurysm growth, size-related characteristics, bottleneck factor, and ellipticity index changed significantly during growth, most size ratios and shape indices showed inconsistent changes among aneurysms. This suggests that, for an accurate rupture prediction, morphological parameters need to be reassessed after growth.
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Yin, Haoran, Chaonan Chen, Qingdong Dong, Pingping Zhang, Quantong Chen, and Lianqi Zhu. "Analysis of Spatial Heterogeneity and Influencing Factors of Ecological Environment Quality in China’s North-South Transitional Zone." International Journal of Environmental Research and Public Health 19, no. 4 (February 16, 2022): 2236. http://dx.doi.org/10.3390/ijerph19042236.
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The ecological environment is important for the natural disaster prevention of human society. The monitoring of ecological environment quality has far-reaching practical significance for the functional construction of ecosystem services and policy coordination. Based on Landsat 8 operational land image (OLI)/thermal infrared sensor (TIRS) remote sensing image data, this study selected the normalized vegetation (NDVI), tasseled cap transformation humidity (WI), bare soil (SI), construction index (NDSI), and land surface temperature (LST) indexes from the aspects of greenness, humidity, dryness, and heat. Using spatial principal component analysis (SPCA) and the remote sensing ecological index (RSEI) analyzed the spatial differentiation characteristics and influencing factors of the original remote sensing ecological index (RSEI0). The results showed that: (1) the overall RSEI average value of the Qinling-Daba Mountains in 2017 was 0.61, and the ecological environment quality was at a “Good” level. Greenness contributed the most to the comprehensive index of the area, and vegetation distribution had a significant impact on the ecological environment quality of the study area. Heat is a secondary impact, and it has an inhibitory effect on habitat quality; (2) the overall distribution of regional ecological environment quality was quite different, with the ecological environment quality level showing a decreasing trend from low to high altitude; RSEI0 spatial heterogeneity at the optimal scale of 2 km was the largest, and the nugget effect was 88% which indicated a high degree of spatial variability, mainly affected by structural factors; (3) Slope, relief amplitude, elevation, the proportion of high-vegetation area, proportion of construction land area, and average population density significantly impact the spatial differentiation of RSEI0. The explanatory powers of slope and relief amplitude were 56.1% and 65.3%, respectively, which were the main factors affecting the spatial differentiation of the ecological environment quality in high undulation. The results can provide important scientific support for ecological environment construction and ecological restoration in the study area.
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M. V., Jawahar Vishnu M., Parthiban K. K. T., Umesh Kanna S., Radhakrishnan S., Uttam Kumar, and Taimoor Hassan Farooq. "Characterizing the Morphological Descriptors of Thirty Seed Sources of Teak (Tectona grandis L.f.) Concerning Sustainable Forestry." Sustainability 14, no. 19 (September 22, 2022): 12012. http://dx.doi.org/10.3390/su141912012.
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Teak (Tectona grandis L.f.) plantations have increased recently in India; however, morphological descriptors for teak are still lacking. Thus, the goal of this work was to develop descriptors based on morphological characteristics. Among 30 seed sources collected from different states of India, 24 morphological descriptors, including leaf length, leaf width, presence of petiole, petiole length, leaf shape, shape of leaf apex, shape of leaf base, leaf texture, phyllotaxy, leaf attitude, leaf margin, leaf margin undulation, leaf brightness, leaf venation, leaf main vein, leaf veins, leaf vein color, leaf color, leaf pubescence, young leaf color, number of internodes, internodal length, trunk spots, and trunk color, were developed based on leaf and stem characteristics. These seed sources exhibited a difference in all traits except leaf shape, shape of leaf apex, leaf phyllotaxy, leaf margin, leaf venation, leaf main vein, and presence of trunk spots. The Jaccard similarity index was used to calculate the genetic similarity between the sources, and the Unweighted Pair Group Method with Arithmetic Mean (UPGMA) method was used to perform a cluster analysis (four groups at a similarity of 0.5 were obtained). According to the observations made, most of the sources exhibited high similarity, which indicates that only a few characteristics can be used to distinguish the sources.
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Yu, Jiayong, Deliang Lv, Maoyi Tian, Yang Zhang, Jingfeng Lin, Fei Xu, and Guigang Shi. "Automatic extraction of tunnel centerline and cross-sections from 3D point clouds." Engineering Research Express 4, no. 1 (February 23, 2022): 015026. http://dx.doi.org/10.1088/2631-8695/ac5468.
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Abstract The accurate extraction of tunnel centerline and tunnel cross-section plays a vital role in many tunnel deformation monitoring projects. To address this issue, An automatic data extraction method for a tunnel centerline and cross-section is proposed based on the three-dimensional laser scanning data. A k-dimensional tree index is first constructed based on the horizontal projection of the tunnel point clouds, and then a series of seed points is selected as the center of several neighborhood point sets with different radii; the difference set region, which will be used to calculate the tunnel horizontal centerline point based on the convex hull operation, is obtained. Then, according to the horizontal centerline, the cross-section of the tunnel point clouds is extracted and fitted to obtain the tunnel cross-section parameters and three-dimensional centerline. Based on the design values of the three-dimensional centerline and tunnel radius, the overall model of the tunnel can be constructed and applied to the visual analysis of tunnel deformation. The experimental results show that the proposed method can accurately obtain the tunnel centerline and cross-section parameters, with a minimal 0.011 cm error for the extraction of the horizontal centerline. The proposed tunnel model could simulate the undulation of the tunnel surface well and provide reference values for similar cases.
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Laaksamo, Elisa, Manasi Ramachandran, Juhana Frösen, Riikka Tulamo, Marc Baumann, Robert M. Friedlander, Robert E. Harbaugh, et al. "Intracellular Signaling Pathways and Size, Shape, and Rupture History of Human Intracranial Aneurysms." Neurosurgery 70, no. 6 (January 24, 2012): 1565–73. http://dx.doi.org/10.1227/neu.0b013e31824c057e.
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Abstract BACKGROUND: Size and morphological features are associated with intracranial aneurysm (IA) rupture. The cellular mechanisms of IA development and rupture are poorly known. OBJECTIVE: We studied the expression and phosphorylation of different intracellular signaling molecules in the IA wall compared with IA morphological features to understand better the cellular pathways involved in IA development and wall degeneration. METHODS: Nine ruptured and 17 unruptured human IA samples were collected intraoperatively. The expression levels and phosphorylation state of 3 mitogen-activated protein kinases (c-Jun N-terminal kinase [JNK], p38, extracellular signal-regulated kinase [ERK]), Bcl-2 antagonist of cell death (Bad), mammalian target of rapamycin (mTOR), cyclic AMP response element binding protein (CREB), and Akt were determined by Western blotting. The localization of signaling proteins was determined by immunofluorescence. From 3-dimensional segmentation of computed tomography angiographic data, size and shape indexes were calculated. RESULTS: We found a 5-fold difference in phospho-Bad levels between ruptured and unruptured IAs. Phospho-mTOR was downregulated 2.5-fold in ruptured IAs. Phospho-p54 JNK, phospho-p38, and phospho-Akt levels correlated positively with IA size. Phospho-CREB levels were significantly associated with nonsphericity and ellipticity indexes. Phospho-Akt and phospho-p38 correlated negatively with undulation index. CONCLUSION: The signaling pathway profile (apoptosis, cell proliferation, stress signaling) differs between ruptured and unruptured IAs and is associated with IA geometry. Our results increase the knowledge of IA development and wall degeneration.
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Ercan, Fabian EZ, Hugo Jan De Boer, and Friederike Wagner-Cremer. "A growing degree day inference model based on mountain birch leaf cuticle analysis over a latitudinal gradient in Fennoscandia." Holocene 30, no. 2 (August 1, 2019): 344–49. http://dx.doi.org/10.1177/0959683619865605.
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Cuticle analysis performed on fossil Betula nana (L.) leaves provides a strong proxy to reconstruct past growing season thermal properties expressed as growing degree days (GDD5). This proxy is so far available for the dwarf birch only and, therewith, restricted to regions or past periods of subarctic climatic conditions. In this study, we analysed modern leaf samples of mountain birch ( Betula pubescens spp. czerepanovii (N. I. Orlova) Hämet-Ahti), which has a wider temperature range than the dwarf birch B. nana. The strong latitudinal climate gradient over Fennoscandia provides a unique opportunity to track growing season temperature imprints in the epidermis cell morphology of the modern mountain birch. We quantified the GDD5-dependent epidermal cell expansion, expressed as the undulation index (UI), over a 10° latitudinal transect translating to a range from ~1500°C to ~600°C GDD5 in 2016. Our results indicate that even in mountain birch the UI is positively correlated to GDD5 and, moreover, is largely independent of regional habitat conditions such as daylight length and precipitation. These results imply that in addition to the earlier studied (sub-)arctic dwarf birch, the closely related mountain birch can also be utilized in GDD5 reconstructions. The abundant presence of fossil mountain birch leaves in sediments from warmer than (sub)arctic palaeoclimates enables the reconstruction of growing season climate dynamics over past phases of climate change, overcoming earlier restrictions of the proxy related to spatial and temporal species occurrence as well as local light regimes.
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Toraya, Hideo. "Finding the best-fit background function for whole-powder-pattern fitting using LASSO combined with tree search." Journal of Applied Crystallography 54, no. 2 (February 14, 2021): 427–38. http://dx.doi.org/10.1107/s1600576720016751.
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A new linear function for modelling the background in whole-powder-pattern fitting has been derived by applying LASSO (least absolute shrinkage and selection operator) and the technique of tree search. The background function (BGF) consists of terms b n L(2θ/180)−n/2 and b n H(1 − 2θ/180)−n/2 for the low- and high-angle sides, respectively. Some variable parameters of the BGF should be fixed at zero while others should be varied in order to find the best fit for a given data set without inducing overfitting. The LASSO algorithm can automatically select the variables in linear regression analysis. However, it finds the best-fit BGF with a set of adjustable parameters for a given data set while it derives a different set of parameters for a different data set. Thus, LASSO derives multiple solutions depending on the data set used. By regarding the individual solutions from LASSO as nodes of trees, tree structures were constructed from these solutions. The root node has the maximum number of adjustable parameters, P. P decreases with descending levels of the tree one by one, and leaf nodes have just one parameter. By evaluating individual solutions (nodes) by their χ2 index, the best-fit single path from a root node to a leaf node was found. The present BGF can be used simply by varying P in the range 1–10. The BGF thus derived as a final single solution was incorporated into computer programs for Pawley-based whole-powder-pattern decomposition and Rietveld refinement, and the performance of the BGF was tested in comparison with the polynomials currently widely used as the BGF. The present BGF has been demonstrated to be stable and to give an excellent fit, comparable to polynomials but with a smaller number of adjustable parameters and without introducing undulation into the calculated background curve. Basic algorithms used in statistics and machine learning have been demonstrated to be useful in developing an analytical model in X-ray crystallography.
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Shadwick, R. E., S. L. Katz, K. E. Korsmeyer, T. Knower, and J. W. Covell. "Muscle dynamics in skipjack tuna: timing of red muscle shortening in relation to activation and body curvature during steady swimming." Journal of Experimental Biology 202, no. 16 (August 15, 1999): 2139–50. http://dx.doi.org/10.1242/jeb.202.16.2139.
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Cyclic length changes in the internal red muscle of skipjack tuna (Katsuwonus pelamis) were measured using sonomicrometry while the fish swam in a water tunnel at steady speeds of 1.1-2.3 L s(−)(1), where L is fork length. These data were coupled with simultaneous electromyographic (EMG) recordings. The onset of EMG activity occurred at virtually the same phase of the strain cycle for muscle at axial locations between approximately 0.4L and 0.74L, where the majority of the internal red muscle is located. Furthermore, EMG activity always began during muscle lengthening, 40–50 prior to peak length, suggesting that force enhancement by stretching and net positive work probably occur in red muscle all along the body. Our results support the idea that positive contractile power is derived from all the aerobic swimming muscle in tunas, while force transmission is provided primarily by connective tissue structures, such as skin and tendons, rather than by muscles performing negative work. We also compared measured muscle length changes with midline curvature (as a potential index of muscle strain) calculated from synchronised video image analysis. Unlike contraction of the superficial red muscle in other fish, the shortening of internal red muscle in skipjack tuna substantially lags behind changes in the local midline curvature. The temporal separation of red muscle shortening and local curvature is so pronounced that, in the mid-body region, muscle shortening at each location is synchronous with midline curvature at locations that are 7–8 cm (i.e. 8–10 vertebral segments) more posterior. These results suggest that contraction of the internal red muscle causes deformation of the body at more posterior locations, rather than locally. This situation represents a unique departure from the model of a homogeneous bending beam, which describes red muscle strain in other fish during steady swimming, but is consistent with the idea that tunas produce thrust by motion of the caudal fin rather than by undulation of segments along the body.
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Pomazanov, N. N. "NATURE OF MORPHOLOGICAL VARIABILITY OF THE MEDULLAR PART OF HEAD IN DIFFERENT ANTHROPOLOGICAL TYPES OF THE MODERN POPULATION OF BELARUS." Health and Ecology Issues, no. 3 (September 28, 2011): 110–14. http://dx.doi.org/10.51523/2708-6011.2011-8-3-22.
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The dynamics in the population values of head index, which reflects the correlation between the longitudinal and transversal diameters of the medullar part in different generations of the modern Byelorussian population, has an undulating nature: after the increase in the head index there is its reduction, which leads to the alternation of more and less brachycephalic generations. The intergenerational dynamics of the population values of the head index in the population with different anthropological types differs in the form of the undulating curve, which reflects the intrapopulation`s relationships in the line of the generations.
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Mayerhöfer, Thomas G., Susanne Pahlow, Uwe Hübner, and Jürgen Popp. "Removing interference-based effects from infrared spectra – interference fringes re-revisited." Analyst 145, no. 9 (2020): 3385–94. http://dx.doi.org/10.1039/d0an00062k.
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Substantial refractive index mismatches between substrate and layers lead to undulating baselines and changes of band intensity, shape and position. For proper spectrum interpretation, all of these effects must be removed.
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Skempton, A. W., D. Norbury, D. J. Petley, and T. W. Spink. "Solifluction shears at Carsington, Derbyshire." Geological Society, London, Engineering Geology Special Publications 7, no. 1 (1991): 381–87. http://dx.doi.org/10.1144/gsl.eng.1991.007.01.34.
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AbstractA clayey solifluction deposit of Devensian age on the lower slopes of a broad valley in Namurian mudstone is about 1.2 m thick and near its base are shear surfaces, gently undulating and occupying on average 40% of the length (56 m) examined in trial pits. Within a shear zone up to 2 mm in thickness the clay mineral aggregates are aligned sub-parallel to the shear surface; otherwise the aggregates are in random orientation. Tests show that strength on the shear surface falls to the residual value (c′ = 0, φr′ = 12°) after small displacements. The resultant peak strength parameters of the deposit, allowing for the undulating and discontinuous nature of the shears, are c′ = 6 kPa and φ′ = 18°; as compared to c′ = 10 kPa and φ′ = 20° for the intact clay. Average index properties are w = 40, LL = 75, PL = 32 and clay fraction = 62%.
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Oduyebo, O. F., M. N. Ono, and S. O. Eteje. "FITTING OF A TRANSFORMATION GEOID MODEL TO THE GRAVIMETRIC-GEOMETRIC GEOID MODEL OF BENIN CITY." FUDMA JOURNAL OF SCIENCES 5, no. 4 (January 17, 2022): 56–62. http://dx.doi.org/10.33003/fjs-2021-0504-781.
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The application of the transformation geoid model in Benin City has necessitated its fitting to the existing gravimetric-geometric geoid model of the study area. The transformation geoid model was determined using the Kotsakis (2008) model for the transformation of global geoid heights to local geoidal undulations. To obtain its accuracy, the root mean square error (RMSE) index was applied. The computed accuracy is 2.0172 m. To apply the determined geoid model in the study area, as well as improving on the computed accuracy, the model was fitted to the gravimetric-geometric geoid model of the study area. The fitting result shows that geoid heights can be computed using the determined geoid model with an accuracy of 1.1041 m in the study area.
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Tao, Tao, Jiada Li, Kunlun Xin, Peng Liu, and Xiaolan Xiong. "Division method for water distribution networks in hilly areas." Water Supply 16, no. 3 (December 23, 2015): 727–36. http://dx.doi.org/10.2166/ws.2015.182.
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Water distribution systems in hilly areas are always divided into several zones due to the undulating terrain. The present approach of dividing water distribution systems lacks an assessment index and is characterized by a low degree of automation. With the building of a mathematical model, this paper introduces two indicators – pressure limitation and pressure variation – to enable the automatic division of the water supply pipe network. It prioritizes economic index as the objective function in the evaluation of the division of water distribution systems in hilly areas, and then selects the optimal division scheme by generic algorithm in a large number of candidates. The SY terrain in YW City China is used for verification. Compared to traditional water supply partition methods, this procedure is easier to operate time-savingly by staff and is more automatic.
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Li, Haixing, Jinrong Liu, Xiangxu Bu, Xuezhi Feng, and Pengfeng Xiao. "An Integrated Shadow-Adjusted Snow-Aging Index for Alpine Regions." Remote Sensing 12, no. 8 (April 15, 2020): 1249. http://dx.doi.org/10.3390/rs12081249.
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Detecting the variations in snow cover aging over undulating alpine regions is challenging owing to the complex snow-aging process and shadow effect from steep slopes. This study proposes a novel snow-cover status index, namely shadow-adjusted snow-aging index (SASAI), portraying the integrated aging process within the Manas River Basin in northwest China. The Environment Satellites HJ-1A/B optical images and in-field measurements were used during the snow ablation and accumulation periods. The in-field measurements provide a reference for building a candidate library of snow-aging indicators. The representative aging samples for training and validation were obtained using the proposed time-gap searching method combined with the target zones established based on the altitude of snowline. An analytic hierarchy process was used to determine the snow-aging index (SAI) using multiple optimal snow-aging indicators. After correction by the extreme value optimization algorithm, the SASAI was finally corrected for the effects of shading and assessed. This study provides both a flexible algorithm that indicates the characteristics of snow aging and speculation on the causes of the aging process. The separability of the SAI/SASAI and adaptability of this algorithm on multiperiod remote sensing images further demonstrates the applicability of the SASAI to all the alpine regions.
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Tanaka, Shotaro, Shuto Suzuki, Tomohiro Mishima, and Kazuhiro Kanda. "Performance of BL07A at NewSUBARU with installation of a new multi-layered-mirror monochromator." Journal of Synchrotron Radiation 28, no. 2 (February 11, 2021): 618–23. http://dx.doi.org/10.1107/s1600577520016781.
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Soft X-rays excite the inner shells of materials more efficiently than any other form of light. The investigation of synchrotron radiation (SR) processes using inner-shell excitation requires the beamline to supply a single-color and high-photon-flux light in the soft X-ray region. A new integrated computing multi-layered-mirror (MLM) monochromator was installed at beamline 07A (BL07A) of NewSUBARU, which has a 3 m undulator as a light source for irradiation experiments with high-photon-flux monochromatic light. The MLM monochromator has a high reflectivity index in the soft X-ray region; it eliminates unnecessary harmonic light from the undulator and lowers the temperature of the irradiated sample surfaces. The monochromator can be operated in a high vacuum, and three different mirror pairs are available for different experimental energy ranges; they can be exchanged without exposing the monochromator to the atmosphere. Measurements of the photon current of a photodiode on the sample stage indicated that the photon flux of the monochromatic beam was more than 1014 photons s−1 cm−2 in the energy range 80–400 eV and 1013 photons s−1 cm−2 in the energy range 400–800 eV. Thus, BL07A is capable of performing SR-stimulated process experiments.
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Pardoyo, Bambang, Briota Akhbar Wirawan, and Khoirul Huda. "Analysis Of The Residual Red Soil Shear Test With The Slurry Method In The Regency Of Semarang." TEKNIK 42, no. 1 (May 4, 2021): 97–105. http://dx.doi.org/10.14710/teknik.v42i1.33261.
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Residual soil is found in most areas with mountainous, hilly, and undulating topography. This soil is marked by red or brown color. This study aims to determine the physical and mechanical properties of soil in the original soil and residual soil conditions using the slurry method. Research objects were taken from residual red soil of The East Ungaran District, Bergas District, and Bawen District. Analysis of the physical and mechanical properties test shows that the soil sample is a type of clay with kaolinite constituent minerals and moderate swelling ability, and direct shear testing from locations L1, L2, and L3 obtained residual peak shear angles using the slurry method of 29,249 °; 31,341 °; 31,964 ° and constant residual shear angle value of 8,082 °; 8,138 °; 7,294 °, the value of the original soil shear angle has a value of 32.82 °; 31.44 °; 31.98. The higher the value of the plasticity index, the higher the value of the free swell. The relationship between the plasticity index and the value of the residual peak shear angle shows that the results of the peak shear angle and the plasticity index are still within the scope of standard deviation. The value of the constant residual shear angle with the slurry method is much smaller than the test result graph.
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Costello, M. J., T. N. Oliver, and L. M. Cobo. "Intercellular junctions in thin sections of human senile cataracts." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 864–65. http://dx.doi.org/10.1017/s0424820100156304.
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The ultrastructural analysis of normal and cataractous lenses is often hindered by incomplete fixation especially of the centers of the lenses. To overcome this limitation, we have achieved good preservation by chemically fixing 50-200 um thick vibratome sections1 of six human senile cataractous lens nuclei obtained after extracapsular surgery. The remaining nuclear core of each lens was deep yellow to amber and contained central opacities. Fresh vibratome sections (15-30 per lens) were examined in the light microscope (FIG. 1) or were prepared for EM. Fixed and embedded whole vibratome sections were usually bisected and examined along a diameter by trimming successive plateaus (FIG. 2 inset) which gave us access to most regions within the lenses.Whole sections in the light microscope (FIG. 1) consistently showed rings of varying density. Undetectable in uncut lenses, the rings may represent slight discontinuities in composition, refractive index or adherence of layers of fiber cells. These rings roughly correspond to the location of cracks in sections which appear after EM processing (FIG.2 & 3). Fiber cells within these lenses generally displayed complex and irregular shapes, but the cells were well preserved with distinct cell boundaries. We emphasize here the common features of the nuclear cataracts which all contained severe enough opacities to warrant surgical removal but in which the cells appeared to remain intact. Adjacent cells interdigitate with irregular protrusions (FIG. 4). Differential cytoplasmic density between neighboring cells is suggestive of variations in refractive index which might cause excessive light scattering. In this same region in FIG. 4 we also note that dense staining material is present in the extracellular space appearing between the undulating membranes of adjacent cells (FIG. 4, inset). We know of no other report of such deposits in normal or abnormal lenses. The thickness of these deposits may also be sufficient to scatter light. A prominent feature of the lens preparations regardless of location is the presence of undulating membranes which are part of tongue-and-groove junctions (FIG. 5). It is noteworthy that the convex side of the curves is consistently well-preserved and is probably the crystalline array of protein noted in other studies, including in human autopsy lenses. It is not known whether cell communication occurs in the nucleus via gap junctions, but structures with the distinctive morphology of gap junctions are present even within senile cataracts (FIG. 5). FIG. 5 also shows a complex clustering of undulating junctions. The multilamellar membrane cluster in FIG.6, which is similar to structures reported in Emory mouse cataracts, is not commonly seen within the mass of lens tissue but is seen at cut surfaces and within cracks where cells are pulled apart.
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Zhou, Sheng-quan, Da-wei Zhou, Yong-fei Zhang, and Wei-jian Wang. "Study on Physical-Mechanical Properties and Microstructure of Expansive Soil Stabilized with Fly Ash and Lime." Advances in Civil Engineering 2019 (November 14, 2019): 1–15. http://dx.doi.org/10.1155/2019/4693757.
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Fly ash and lime have been frequently employed to reduce the swelling potential of expansive soils. Laboratory experiments, scanning electron microscopy (SEM), and X-ray diffraction (XRD) were used in this study to investigate the stabilizing effect of fly ash and lime on expansive soils in the Jianghuai undulating plain area. The comparison was drawn between the variation laws of physical parameters, mechanical properties, microstructure, and mineral composition of expansive soil before and after being stabilized. Experimental results suggest that, after 5% lime is added based on fly ash, the plasticity index of the expansive soil decreases by 64.9%, the free swelling ratio is reduced to about 10%, the unloading swelling ratio is reduced to nearly 4%, and the stabilized soil no longer exhibits the expansive property. The unconfined compressive and tensile strengths of the stabilized soil increase first and then decrease with the rising in fly ash content. After the addition of 5% lime, both the unconfined compressive and tensile strengths increase significantly. The optimum modifier mixture ratio is obtained as 10% fly ash + 5% lime. The SEM images reveal that the microstructures of the stabilized expansive soil vary from an irregular flake-like and flocculent structures to blocky structures, and the soil samples compactness is enhanced. XRD results indicate that quartz is the main component of the stabilized soil. These are the underlying causes of the rise in the strength. The conclusions of this study can be referenced for the engineering design and construction of expansive soil in Jianghuai undulating plain area.
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Bhasker, Bisht, and R. C. Joshi. "Relief and slope characteristics of Lohawati river catchment in Kumaun Himalaya, Uttarakhand." Disaster Advances 15, no. 8 (July 25, 2022): 9–18. http://dx.doi.org/10.25303/1508da09018.
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Geomorphologists use river basin as an ideal unit of the earth surface for the study of its landforms. Relief and slope are essential factors which determine and control the origin and evolution of any river catchment. Relief and slope studies also highlight the facts about changing nature of the river catchment. The Lohawati River catchment is located in lesser Himalaya in Champawat district of Uttarakhand state. In the present study, an attempt has been made to study the relief and slope characteristics of the Lohawati river catchment using geospatial technique. The altitude of the catchment area decreases from west to east direction. The slope map indicates that Lohaghat and Champawat towns are situated in the gentle slope category. The very low dissection index and very low relative relief in the Champawat area and in some parts of Lohaghat at the western side of the catchment are characterized by more aggradation processes and are less prone to soil erosion. Relief profiles show the surface undulations because of erosion by Lohawati River and its tributaries.
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Ghosh, Alokananda, and Dr Biswaranjan Mistri. "Obstacles in the Utilisation of Maternal Health Care Services in Murarai-II C.D. Block, Birbhum District, West Bengal, India." Space and Culture, India 4, no. 3 (March 31, 2017): 40. http://dx.doi.org/10.20896/saci.v4i3.224.
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Improving maternal health was one of the eight Millennium Development Goals (MDGs) and now it is one of the targets of 17 point Sustainable Development Goals (SDGs). The utilisation of Maternal Health Care Services (MHCSs) is a complex phenomenon and it is influenced by several factors, like-health care seeking behaviour of the cohorts belonging to different socio-economic and cultural background, distance of the facility centres, type and conditions of the roads including undulating surface, transportation cost, type and availability of transportation mode along with the factors related to the accountability and surveillances of the health care services. Therefore, clear understanding and discussion is needed to draw an association between MHCSs and its influential factors. The objectives of the study are to estimate the impact of accessibility on the underserved status of MHCSs and on the utilisation of MHCSs through paucity index. In addition, the study aims to evaluate the causal relationships between underserved situation and obstacle score with the paucity index of MHCS utilisation.The empirical observation unfolds that the provision and utilisation of MHCSs are strongly dependent on accessibility and distance. The situation is aggravating for proper delivery of services, which is responsible for the increasing obstacle score and paucity index, especially in remote sub- centres of Murarai-II C.D. Block of Birbhum District.
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Raj, John Kuna. "SWELLING CLAY MINERALS AND SLOPE CUT FAILURES IN THE GARINONO FORMATION ALONG JALAN SUNGAI HITAM, LIBARAN, SANDAKAN." Geological Behavior 4, no. 1 (March 12, 2020): 29–34. http://dx.doi.org/10.26480/gbr.01.2020.29.34.
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Jalan Sungai Hitam in the Sandakan Peninsula traverses a flat to gently undulating terrain of low hills and ridges surrounded by broad alluvial flats. Recent slope cuts expose bluish to dark grey mudstones of the Garinono Formation containing pebble to boulder sized, angular to rounded, blocks of sandstone and other rock types. Slump-mud flows have occurred at most of the slope cuts; the failed materials characterized by desiccation cracks and fissures. Soil index properties, including consistency limits and grain size analyses, indicate that the mudstones have a medium to high swell potential. X-ray diffraction analyses show the clay minerals present to be kaolinite, illite and randomly interstratified illite-montmorillonite (a swelling clay mineral). The mudstones are thus sensitive to atmospheric wet-dry cycles with repeated swelling and shrinkage giving rise to the desiccation cracks and fissures, The cracks and fissures reduce the shear strength of the mudstones and allow for the infiltration of rainwater which initiates the slump-mud flows. It is concluded that earthworks in areas of the Garinono Formation in eastern Sabah need to consider the presence of swelling clay minerals; an occurrence that can be inferred from evaluating soil index properties.
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Kirkwood, S., E. Belova, K. Satheesan, T. Narayana Rao, T. Rajendra Prasad, and S. Satheesh Kumar. "Fresnel scatter revisited – comparison of 50 MHz radar and radiosondes in the Arctic, the Tropics and Antarctica." Annales Geophysicae 28, no. 10 (October 29, 2010): 1993–2005. http://dx.doi.org/10.5194/angeo-28-1993-2010.
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Abstract. High-resolution radiosondes and calibrated radars operating close to 50 MHz, are used to examine the relationship between the strength of radar scatter and refractive index gradient. Three radars are used, in Kiruna in Arctic Sweden, at Gadanki in southern India and at the Swedish/Finnish base Wasa/Aboa in Queen Maud Land, Antarctica. Calibration is accomplished using the daily variation of galactic noise measured at each site. Proportionality between radar scatter strength and the square of the mean gradient of potential refractive index, M2, is found in the upper troposphere and lower stratosphere at all three sites, confirming previously reported results from many VHF radars. If the radar scatter is interpreted as Fresnel scatter, the constant of proportionality between radar scatter and M2 is found to be the same, within the calibration uncertainties, for all three radars. The radiosondes show evidence of distinct layering with sharp gradients, extending over 10s of kilometers horizontally, but the scatter is found to be two orders of magnitude weaker than would be expected from true Fresnel scatter from such layers. Using radar reflectivities resolved to a few 100 ms, we show that this is due to strong temporal variability in the scattering conditions, possibly due to undulations of the scattering layers. The constancy of the radar scatter – M2 relationship between the different sites suggests an unexpected uniformity in these perturbations between very different regions of the globe.
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Kyamulesire, Bruno, Paul Dare Oluyori, and Sylvester Okiemute Eteje. "COMPARATIVE ANALYSIS OF THREE PLANE GEOMETRIC GEOID SURFACES FOR ORTHOMETRIC HEIGHT MODELLING IN KAMPALA, UGANDA." FUDMA JOURNAL OF SCIENCES 4, no. 3 (September 11, 2020): 48–51. http://dx.doi.org/10.33003/fjs-2020-0403-255.
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The conversion of theoretical, as well as geometric heights to practical heights requires the application of geoidal undulations from a geoid model. The various global geopotential models that are readily available for application in any part of the world do not best-fit regions, as well as countries. As a result, there is a need to determine the local geoid models of local areas, regions and countries. This study determines the local geoid model of Kampala in Uganda for orthometric heights computation by comparing three plane geometric geoid surfaces. A total of 19 points were used in the study. The least squares adjustment technique was applied to compute the models’ parameters. Microsoft Excel programs were developed for the application of the models in the study area. The Root Mean Square Index was applied to compute the accuracy of the models. The three geometric geoid models were compared using their accuracy to determine which of them is most suitable for application in the study area. The comparison results show that the three models can be applied in the study area with more reliability, with greater confidence in model 2.
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Li, Hailian, Peipei Tong, Xijun Zhang, Xixiong Lin, and Bo Li. "Influence of Ultraviolet and Oxygen Coupling Aging on Rheological Properties and Functional Group Index of Warm Mix Asphalt Binder." Materials 13, no. 19 (September 23, 2020): 4216. http://dx.doi.org/10.3390/ma13194216.
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Warm-mixed asphalt (WMA) has the characteristics of low mixing temperature and energy consumption, which makes it more suitable than hot-mixed asphalt for plateau regions (the altitude is above 500 m, and the terrain is relatively flat or has a wide area with certain undulations). However, WMA is subject to severe ultraviolet (UV) aging because the UV radiation in plateau areas is more intense. The asphalt’s aging changes its rheological properties inevitably, and thus degrades the asphalt pavement’s performance. Accordingly, the purpose of this paper is to investigate the effect of UV and oxygen coupling aging on WMA’s rheological properties and functional group index. Temperature and frequency sweep tests were performed with a dynamic shear rheometer. At the same time, the functional group index was used as an indicator to compare the changes in the WMA’s infrared spectrum before and after UV aging. The results showed that WMA’s elasticity increased and its viscosity decreased after aging with UV. Under the condition of UV–oxygen isolation, as the aging period increased, the WMA’s rutting factor increased gradually. The degree of improvement was greater than that under the condition of oxygen isolation. In contrast, the time required for the WMA’s complex shear modulus to recover under the condition of UV–oxygen coupling was delayed. An increase in the peak value of infrared spectrum indicates that the WMA has undergone oxygen aging. The presence and change in the carbonyl group reflects the degree of the WMA’s UV aging, and the UV aging condition had a greater effect on the peak values of the carbonyl and sulfoxide groups.
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Jiang, Xueqin, Shenghui Fang, Xia Huang, Yanghua Liu, and Linlin Guo. "Rice Mapping and Growth Monitoring Based on Time Series GF-6 Images and Red-Edge Bands." Remote Sensing 13, no. 4 (February 6, 2021): 579. http://dx.doi.org/10.3390/rs13040579.
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Accurate rice mapping and growth monitoring are of great significance for ensuring food security and agricultural sustainable development. Remote sensing (RS), as an efficient observation technology, is expected to be useful for rice mapping and growth monitoring. Due to the fragmented distribution of paddy fields and the undulating terrain in Southern China, it is very difficult in rice mapping. Moreover, there are many crops with the same growth period as rice, resulting in low accuracy of rice mapping. We proposed a red-edge decision tree (REDT) method based on the combination of time series GF-6 images and red-edge bands to solve this problem. The red-edge integral and red-edge vegetation index integral were computed by using two red-edge bands derived from GF-6 images to construct the REDT. Meanwhile, the conventional method based on time series normalized difference vegetation index (NDVI), normalized difference water index (NDWI), enhanced vegetation index (EVI) (NNE) was employed to compare the effectiveness of rice mapping. The results indicated that the overall accuracy and Kappa coefficient of REDT ranged from 91%–94% and 0.82–0.87, improving about 7% and 0.15 compared with the NNE method. This proved that the proposed technology was able to efficiently solve the problem of rice mapping on a large scale and regions with fragmented landscapes. Additionally, two red-edge bands of GF-6 images were applied to monitor rice growth. It concluded that the two red-edge bands played different roles in rice growth monitoring. The red-edge bands of GF-6 images were superior in rice mapping and growth monitoring. Further study needs to develop more vegetation indices (VIs) related to the red-edge to make the best use of red-edge characteristics in precision agriculture.
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Lv, Xiangfeng, and Hongyuan Zhou. "Shear Characteristics of Cement-Stabilized Sand Reinforced with Waste Polyester Fiber Fabric Blocks." Advances in Materials Science and Engineering 2019 (July 10, 2019): 1–12. http://dx.doi.org/10.1155/2019/3758413.
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The present paper is devoted to investigate the effects of waste polyester fiber fabric blocks on the strength and mechanical behavior of cemented sand. In the investigation, samples were prepared at four different percentages of waste polyester fiber fabric block content (0.0%, 0.5%, 1.0%, and 1.5% by weight of soil) and two different aspect ratios (2 : 1 and 3 : 1), and conventional triaxial compression tests were carried out after the curing period. The test results indicated that the addition of fibers increased peak and residual shear strengths of cemented sand and changed its brittle behavior to a more ductile one. As the fabric block content increased, the brittleness index and initial stiffness decreased, and the peak strain and internal friction angle increased. The optimal combination of the content and aspect ratio was determined to be 0.5% and 3 : 1. The integration of the fabric blocks with the cemented sand matrix was analyzed by using the scanning electron microscopy (SEM). It is found that the reinforcement effect is related to the bond strength and friction at the interface. The micromechanical properties of the fiber/matrix interface were influenced by the undulations between the fabric block components. In summary, this study presented a low-cost and environment-friendly method for reinforcing cement-stabilized sand.
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Karna, Bikash Kumar, Shobha Shrestha, and Hriday Lal Koirala. "Land Suitability Analysis for Potential Agriculture Land Use in Sambhunath Municipality, Saptari, Nepal." Geographic Base 8, no. 01 (December 31, 2021): 13–30. http://dx.doi.org/10.3126/tgb.v8i01.43464.
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Rapid and unplanned urbanization and haphazard infrastructure development causes pressure on the finite land resource and there is urgent need to preserve the arable land for food security. Land suitability analysis is a technique in which the land quality assessment is performed through interpretation of land properties for allocation of lands for particular use. The present paper attempts to conduct a land suitability analysis to determine the potential sites for agriculture land use in Sambhunath municipality of Saptari district. The criteria/ factors for the land suitability analysis were identified through literatures and modified in the local context through expert opinions and focus group discussions. The evaluation of agriculture land is accomplished using Analytic Hierarchy Process (AHP), Multi-Criteria Evaluation (MCE) and Geographic Information System (GIS). Agriculture suitability index was developed and optimized qualitatively through the strength, weakness, opportunity, and threat (SWOT) analysis. Finally, potential agriculture suitability index map is prepared. The analysis shows almost 3139 ha (29%) lands as 14 highly suitable and 3001 ha (28%) of moderately suitable agriculture land within the municipality. Almost all the suitable agriculture land is located at low land with flat terrain to gentle slope having high natural fertility and mainly in land capability classes I and II. The unsuitable and poorly suitable agriculture land is occupied in the undulating areas and hilly terrain of the Siwalik hill. The study found the GIS tool integrated with MCE-AHP useful in land suitability evaluation process and anticipated that it could act as the planning tool to allocate lands in land use planning for sustainable agricultural practices.
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Wang, Baixue, and Weiming Cheng. "Effects of Land Use/Cover on Regional Habitat Quality under Different Geomorphic Types Based on InVEST Model." Remote Sensing 14, no. 5 (March 5, 2022): 1279. http://dx.doi.org/10.3390/rs14051279.
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Research on habitat quality change is of great significance for regional ecological security. Analysis of spatiotemporal change of habitat quality based on different geomorphic types can restore the background of ecological environment in historical periods and provide scientific support for revealing the evolution law of regional ecological environment quality and ecological restoration. This study aimed to identify the change in habitat quality under different geomorphic types from 1995 to 2018. Based on DEM data, geomorphic types of different scales were divided. The InVEST habitat quality model was used to analyze the spatiotemporal change in habitat quality in individual land use types in the Altay region. The spatiotemporal changes and main influencing factors of habitat quality under the background of different geomorphic types were explored. Remote sensing data was used to analyze the land use/cover changes. Sixteen threat sources, their maximum distance of impact, mode of decay, and sensitivity to threats were also estimated for each land use type. The results showed that habitat quality decreased significantly in 2015, which was related to the rapid expansion of cultivated and construction land as threat sources, as well as the decrease of forestland and grassland as sensitive factors. However, habitat quality improved significantly in 2018, because of the implementation of ecological restoration policy in 2015. Affected by elevation and topographic relief, the geomorphic type with the best habitat quality index was the large undulating middle mountain (0.927) and the worst was the medium altitude platform (0.351). Woodland contributed the most to habitat quality in large undulating middle mountain (35.07), and bare rock gravel land contributed the most to medium altitude platform (127.68). Habitat quality of different geomorphic types showed obvious spatial aggregation, and from high altitude to low altitude showed a banded ladder-like distribution. Changes in habitat quality during the past three decades suggested that the conservation and restoration strategies applied in regional ecosystem were effective. On the basis of the analysis results, four types of zoning management schemes were divided, and the ecological management and conservation measures were put forward. Therefore, this study can help decision makers, especially regarding the lack of data on biodiversity.
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Kalita, Nilim, and Subal Maibangsa. "Soil fertility evaluation of rice soils of Lumbajong block of Karbi Anglong district under hill zone of Assam through nutrient indexing." AN ASIAN JOURNAL OF SOIL SCIENCE 15, no. 2 (December 15, 2020): 81–85. http://dx.doi.org/10.15740/has/ajss/15.2/81-85.
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The Lumbajong block of Karbi Anglong district of Assam is characterized by undulating topography comprising of hillocks and lowland paddy fields. Cultivation of rice in traditional ways for years without adequate and balanced use of chemical fertilizers and with little or no use of organic manure have caused severe fertility deterioration resulting in stagnating or even declining productivity of the paddy field soils. Spatial distributions for organic carbon, available N, available P and available K were examined in the soil samples of selected rice fields in 102 different locations covering six villages in the block to evaluate the fertility status of the block. The study revealed that there is much variation in soil fertility status of soils developed on various land forms in the area as the soils were having low to high in organic carbon (0.42 to1.12 %), low to medium in available nitrogen (175.62 to 376 kg/ha) content; low in available P (3.86 to 28.29 kg/ha) and low to high in available K (71.68 – 439.04 kg/ha) contents. The soils of Lumbajong block were characterized as medium-medium-low-medium (MMLM) category based on the nutrient index calculated with respect to organic carbon, available N, available P and available K.
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Liu, Z., C. Li, Z. Zhao, D. Zhang, F. Wang, and Y. Wang. "EFFICIENT AND ACCURATE FUSION OF MASSIVE VECTOR DATA ON 3D TERRAIN." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences IV-4 (September 19, 2018): 119–24. http://dx.doi.org/10.5194/isprs-annals-iv-4-119-2018.
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<p><strong>Abstract.</strong> This paper presents a viewpoint-related fusion method of massive vector data and 3D terrain, in order to superpose the massive 2D vector data onto the undulating multi-resolution 3D terrain precisely and efficiently. First, the method establishes an adaptive hierarchical grid spatial index for vector data. It will determine the geographic spatial relationship between vector data and the tiles of 3D terrain in the visible area; secondly, this method will use the improved sub-pixel graphics engine AggExt to generate textures for vector data that has been bound to terrain tiles in real time; Finally, considering that a large amount of vector data will generate a lot of 2D textures in the computer memory, the method should release the “expired” vector textures. In this paper, in order to take into account the real-time convergence and the smooth interactivity of 3D scenes, this method will adopt a multi-threading strategy. The experimental results show that this method can realize the real-time and seamless fusion of massive vector objects on the 3D terrain, and has a high rendering frame rate. It can also reduce the aliasing produced by traditional texture-based methods and improve the quality of vector data fusion.</p>
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Whetter, D. A., P. R. Bullock, and L. G. Fuller. "Bromide redistribution as influenced by landscape morphology and pedogenic properties in a variable glacial till landscape: A qualitative examination." Canadian Journal of Soil Science 88, no. 4 (August 1, 2008): 477–90. http://dx.doi.org/10.4141/cjss07072.
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Redistribution of water and associated solutes in undulating to hummocky landscapes affects crop yield via losses of valuable nutrients and negatively impacts groundwater quality. The objective of this study was to determine the influence of qualitative soil-landscape complexes on vertical and lateral redistribution of solutes in a variable glacial till landscape under zero tillage agricultural management by employing a bromide tracer. Tracer plots were established in the fall of 1999 within three sites comprising three representative soil-slope associations. Values of soil development indicators (A horizon thickness, solum thickness, depth to CaCO3, profile development index and organic carbon) generally increased from crest to midslope to depression. Further to this, the occurrence and thickness of eluvial and illuvial horizons increased from crest to midslope to depression. Well-developed, clay-coated blocky Bt horizons with vertical cracking and overlying Ae horizons in depressions appeared to have favoured rapid, downward vertical bromide redistribution. Crest positions were the least anisotropic and vertical redistribution was more important than lateral redistribution at this position. A combination of topographic and pedologic factors resulted in more lateral redistribution at the midslope position relative to crests and depressions. Bromide recovery rates in the top 60 cm of the soil profile indicated that most of the recovered bromide remained within that depth following spring runoff, but had mostly leached below that depth after the growing season, particularly at the depression position. Low bromide recovery rates in the top 30 cm following spring runoff, indicated that reduced availability of fall-applied nutrients for early crop growth could be expected at crest and depression positions following spring runoff. Bromide redistribution was important during both spring recharge and over the growing season at the depression position. Bromide movement below crop rooting depths and into shallow groundwater sources provides evidence that fall-applied nutrients can enter groundwater following both spring melt and growing season runoff in depressional landscape positions, especially in recharge areas. Management practices to reduce over-application of soluble nutrients and surface water accumulation, or both, in depressional areas may be an effective means to lower the risk of groundwater contamination with soluble nutrients without jeopardizing crop yield potential across the majority of the landscape positions in undulating to hummocky glacial till terrain. Key words: Solute redistribution, bromide tracer, soil properties, topography, landscape
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Stoupin, Stanislav, Thomas Krawczyk, David Sagan, Alexander Temnykh, Louisa Smieska, Arthur Woll, Jacob Ruff, et al. "Side-bounce beamlines using single-reflection diamond monochromators at Cornell High Energy Synchrotron Source." Journal of Synchrotron Radiation 28, no. 2 (February 25, 2021): 429–38. http://dx.doi.org/10.1107/s160057752100120x.
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The design and implementation of new beamlines featuring side-bounce (single-reflection) diamond monochromators at Cornell High Energy Synchrotron Source (CHESS) are described. Undulator radiation is monochromated using an interchangeable set of diamond crystal plates reflecting radiation in the horizontal (synchrotron) plane, where each crystal plate is set to one of the low-index Bragg reflections (111, 220, 311 and 400) in either Bragg or Laue reflection geometries. At the nominal Bragg angle of 18° these reflections deliver monochromated X-rays with photon energies of 9.7, 15.9, 18.65 and 22.5 keV, respectively. An X-ray mirror downstream of the diamond monochromator is used for rejection of higher radiation harmonics and for initial focusing of the monochromated beam. The characteristics of the X-ray beam entering the experimental station were measured experimentally and compared with the results of simulations. A reasonable agreement is demonstrated. It is shown that the use of selected high-dislocation-density `mosaic' diamond single-crystal plates produced using the chemical vapor deposition method yields a few-fold enhancement in the flux density of the monochromated beam in comparison with that delivered by perfect crystals under the same conditions. At present, the Functional Materials Beamline at CHESS, which is used for time-resolved in situ characterization of soft materials during processing, has been outfitted with the described setup.
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Farenhorst, A., I. V. Florinsky, C. M. Monreal, and D. Muc. "Evaluating the use of digital terrain modelling for quantifying the spatial variability of 2,4-D sorption by soil within agricultural landscapes." Canadian Journal of Soil Science 83, no. 5 (November 1, 2003): 557–64. http://dx.doi.org/10.4141/s01-037.
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The most sensitive input parameter in many herbicide fate and transport models is the sorption-partitioning coefficient (Kd), a measure of herbicide sorption by soil. Spatial analyses of Kd are traditionally performed using geostatistics, but this approach requires intensive soil sampling and herbicide analysis. This study examined the use of digital terrain modelling as an alternative tool for quantifying the distribution of herbicide sorption within agricultural fields. Soil samples from a conventional-till (CT) and zero-till (ZT) field were analysed for soil organic carbon (SOC), soil pH, clay content, and the 2,4-D ([(2,4-dichlorophenoxy)acetic acid]) soil-water partitioning coefficient. Digital terrain models were used to calculate topographical variables (elevation, slope gradient, slope aspect, horizontal curvature, vertical curvature, mean curvature, specific catchment area, topographic index and stream power index) for each sampling point. Results indicated that topographic variables were adequate predictors of all soil properties in ZT (R2 ranging from 0.64 to 0.76), and of SOC in CT (R2= 0.65, P < 0.001). For CT, 2,4-D sorption by soil was very well predicted with soil properties alone (R2= 0.82, P < 0.001) and with soil properties in combination with topographic variables (R2= 0.85, P < 0.001), but was less predicted by topographic variables alone (R2= 0.50, P < 0.001). For ZT, the level of prediction of 2,4-D sorption by soil was weak with soil properties alone (R2= 0.53, P < 0.001) or when topographical variables alone (R2= 0.56, P < 0.001) were used, but a substantial increase in the level of prediction was achieved when both soil properties and topographic variables were used (R2= 0.73, P < 0.001). We conclude that digital terrain modelling, in combination with soil properties data, is an appropriate approach for predicting the spatial distribution of 2,4-D sorption within undulating-to-hummocky glacial till landscapes in western Canada. Key words: herbicide sorption, topography, zero-tillage, conventional-tillage, digital terrain modelling.
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Luo, Kun, Sixin Liu, Jingxue Guo, Tiantian Wang, Lin Li, Xiangbin Cui, Bo Sun, and Xueyuan Tang. "Radar-Derived Internal Structure and Basal Roughness Characterization along a Traverse from Zhongshan Station to Dome A, East Antarctica." Remote Sensing 12, no. 7 (March 27, 2020): 1079. http://dx.doi.org/10.3390/rs12071079.
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The internal layers of ice sheets from ice-penetrating radar (IPR) investigation preserve critical information about the ice-flow field and englacial conditions. This paper presents a new detailed analysis of spatial distribution characteristics of internal layers and subglacial topography of the East Antarctic ice sheet (EAIS) from Zhongshan Station to Dome A. The radar data of 1244 km along a traverse between Zhongshan Station and Dome A of EAIS were collected during the 29th Chinese National Antarctic Research Expedition (CHINARE 29, 2012/2013). In this study, the Internal Layering Continuity Index (ILCI) and basal roughness were taken as indicators to provide an opportunity to evaluate the past internal environment and dynamics of the ice sheet. Except for the upstream of Lambert Glacier, the fold patterns of internal layers are basically similar to that of the bed topography. The relatively flat basal topography and the decrease of ILCI with increasing depth provide evidence for identifying previous rapid ice flow areas that are unavailable to satellites, especially in the upstream of Lambert Glacier. Continuous internal layers of Dome A, recording the spatial change of past ice accumulation and ice-flow history over 160 ka, almost extend to the bed, with high ILCI and high basal roughness of the corresponding bed topography. There are three kinds of basal roughness patterns along the traverse, that is, “low ξt low η”, “low ξt high η”, and “high ξt high η”, where ξt represents the amplitude of the undulations, and quantifies the vertical variation of the bedrock, and η measures the frequency variation of fluctuations and the horizontal irregularity of the profile. The characteristics of internal layers and basal topography of the traverse between Zhongshan Station and Dome A provide new information for understanding the ancient ice-flow activity and the historical evolution of EAIS.
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Quadrelli, R., and J. M. Wallace. "Varied Expressions of the Hemispheric Circulation Observed in Association with Contrasting Polarities of Prescribed Patterns of Variability*." Journal of Climate 17, no. 21 (November 1, 2004): 4245–53. http://dx.doi.org/10.1175/jcli3196.1.
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Abstract The low-frequency (>5 day period) variability observed within four different subsets of the climatology (H1, L1, H2, and L2) as defined by the high and low index polarities of the two leading principal components (PCs) of the sea level pressure field is compared, with emphasis on distinctive flow configurations and teleconnection patterns. The analysis is based on wintertime 500-hPa height, sea level pressure, and 1000–500-hPa thickness fields derived from the NCEP–NCAR reanalyses for the period of record, 1958–99. “Spaghetti diagrams” display specified contours for ensembles of individual 10-day mean charts extracted from the four different subsets of the climatology. In L1, 10-day mean maps (weak zonal flow at latitudes ∼55°N) exhibit larger undulations in the barotropic component of the flow than those in H1, implying larger particle displacements and deeper penetration of Arctic air masses, particularly into Europe and the eastern United States. Maps in H2 and L2, separated in accordance with the Pacific–North American (PNA)-like second mode, exhibit quite different kinds of planetary wave patterns. The L2 subset (characterized by a retracted Pacific jet) exhibits greater variability over the Gulf of Alaska and over northern Europe. Cold air outbreaks in Europe occur more frequently in L1 than H1, and over western North America, they occur more frequently in L2 than H2. The cold anomalies associated with low polarities of both PCs are observed more frequently than expected based on linear correlation; within the individual subsets of the climatology there are suggestions of multiple circulation regimes; teleconnection patterns for the subsets of the climatology are also discernibly different. These results constitute evidence of nonnormal or nonlinear behavior of 5- and 10-day mean fields and provide indications of how the intraseasonal variability depends on the mean state of the flow in which it is embedded.
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Onisodumeya Elemchukwu James, Blessing Opakirite Green, Mercy Gospel Ajuru, and Victoria Wilson. "Foliar epidermal anatomy and its taxonomic implications within the family Euphorbiaceae in the Niger Delta Region of Nigeria." International Journal of Frontiers in Life Science Research 1, no. 1 (May 30, 2021): 048–55. http://dx.doi.org/10.53294/ijflsr.2021.1.1.0036.
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Micro-morphological investigations of the foliar epidermal anatomy of seven species of the family Euphorbiaceae: Acalypha hispidia Burm. f., A. wilkesiana Mull. Arg, Euphorbia heterophylla L., E. hirta L., Jatropha curcas L., J. gossypifolia L. and Manihot esculenta Crantz was carried out to assess the systematic relevance of epidermal features, stomata and trichome diversity within the family using light microscope and camera. Members of this family contain many important medicinal herbs and there has been increasing misidentification of species in this family. Leaf micro-morphological characteristics are commonly used in the identification and authentication of plants. Results showed that the stomatal index varied from species to species. Epidermal cell shapes were found to be irregular to polygonal on both surfaces of the species. The epidermal cells possess straight to undulating anticlinal walls but in some few cases exhibited wavy to straight anticlinal walls. The presence of papillae was observed to be a unique character of E. heterophylla among the species studied. The stomatal types observed were Anisocytic, Anomocytic, Diacytic, tetracytic, paracytic, and actinocytic. The stomatal complex was mainly amphistomatic except for A. wilkesiana that was hypostomatic. The hypostomatic character of A. wilkesiana as reported in this paper is the first of such report as previous report found was amphistomatic. Non-glandular, multiseriate uniseriate and in some cases branched trichome types were observed only on both surfaces of A. wilkesiana and E. hirta but absent on all other studied species. This study revealed detailed descriptive micromorphological structures which could serve as a source of information and reference for the taxonomic description, identification and delineation of the species studied.