Morphometric Factors Research Articles

Effect of Propolis Administration on the Endocrine Functions and Histopathology of Pancreas in Streptozotocin-Induced Diabetic Rats

This study was performed to investigate the hypoglycemic properties of Propolis and their possible role on pancreatic's tissue. Diabetes mellitus was induced in 45 adult male albino rats and the animals were divided into three groups; Negative control group received standard diet; Positive group diabetic untreated group; Propolis treated group supplemented with (0.3 g/Kg/day) for 2 weeks after the induction of diabetes by streptozotocin. At the end of the experiment, blood was collected from the abdominal aorta. A heparinized tube was used for collection of plasma for measurement of lipid peroxidation products, insulin, glucagon and fasting blood glucose. Pancreas were isolated and stained with hematoxylin and eosin (HE), histoimmunological and morphometric factors were studied. The results of this study showed that Propolis was able to reduce blood glucose significantly compared with the diabetic untreated group. Hypercellularity and density of B cells increased in pancreatic tissue, islets size and percent of B cells increased significantly in Propolis treated group which may signify regeneration of islets or B cells in Propolis treated rats. In the current study, we have demonstrated that, both structural and functional improvements of pancreas. Further researches are highly needed to clarify the specific molecular and cellular targets of various constituents of Propolis.

Flash Flood Hazard Mapping Using Satellite Images and GIS Tools: A case study of the central High Atlas (Morocco)

Abstract. Flash flood is generally defined as a rapid onset of flood with a short duration and a relatively high peak discharge. It occurs rapidly, generally within one hour of rainfall, and sometimes accompanied by landslides, mud flows, bridge collapse, damage to buildings, and fatalities (Hapuarachchi et al., 2011). They cause extensive disruptions to a diverse range of living, working, societal, and spatial environments, the raison why they are reported to be one of the deadliest and most expensive natural hazards worldwide. Flood damages do not only depend on precipitation amounts but are also a consequence of geomorphological factors and human influences (Maruša et al., 2014) and in this study, the main attention is particularly concentrated on geomorphological factors to flooding. Flash flood events can be characterized by the amount of rain responsible to their occurrences and their duration. Leaving aside droughts, floods are one of the most dangerous meteorological hazards in Morocco, followed by wind-/sandstorms, with the largest frequency of occurrence and the largest number of victims (EM-Dat. 2014). Heavy rains often induce floods in Morocco, including flash floods, riverine floods and mud floods during the rainy season (Theilen-Willige, B. 2015). For example, in 2014, The violent storms of 22–30 November 2014, resulted in flash floods and rivers floods in large parts of Southern Morocco. The Guelmim area was the most affected part with at least 32 fatalities and important infrastructure damages. In August 2015 Heavy rain (299m) causes flooding in some area parts of the Geoparc of Mgoun (central High Atlas, Moroco): such as Tllouguit, Zawiat Ahancal,and Ait Bou Guemmez Indeed, this episode affected regional roads, bridges, schools and agricutural infrastractures, water supply and electrical networks and caused several people homeless, 3 deaths and important infrastructure damages. The torrential rains caused flooding of Ahancal and Bou Gemmez river and submerging roads and bridges. This flooding event rose the question of whether and how remote sensing and GIS tools could be used in an effective manner in order to contribute to a better understanding of the factors leading to this flooding hazard and how to mitigate damage in future by providing maps of areas that have been flooded in the past and areas that are susceptible to flooding due to their morphologic settings during extreme precipitation events. The flooding hazard in the High atlas of Azilal region initiated this study in order to investigate the use of remote sensing and geographic information system (GIS) for the detection and identification of areas most likely to be flooded in the future again due to their morphologic properties during similar weather conditions. By combining morphometric analysis of the investigation area involving the quantitative analysis of the landforms based on Digital Elevation Model (DEM) data (Aster GDEM, SRTM-DEM, ALOS PALSAR-DEM) and visual interpretation based on satellite image. The resulting maps of weighted overlay procedures, aggregating causal, morphometric factors influencing the susceptibility to flooding (lowest height levels, flattest areas), allowed for the distinguishing of areas with higher, medium and lower susceptibility to flooding. Thus, GIS and remote sensing tools contribute to the recognition and mapping of areas and infrastructure prone to flooding in this area. Satellite radar data as Sentinel 1, A and B, with acquisition times at or near the flooding events help to identify flooded areas due to the typical mirror-like radar signal reflection of water bodies. Optical satellite data (Sentinel 2, Landsat 8) (often useless during the flooding events because of the cloud cover) taken after flooding events can be used to monitor the traces of flash floods such as sediment accumulation areas or erosional features. Merging this information with infrastructural data in a GIS environment contributes to the detection of flooding hazard prone areas and, thus, to hazard preparedness.

Рельєф стартових зон виникнення снігових лавин на Чорногірському хребті Українських Карпат

Досліджено проблему такого небезпечного стихійного явища, як лавини. Виконано аналіз основних чинників лавиноутворення, а саме морфометричних, метеорологічних та антропогенних. Запропоновано використання геоінформаційних технологій для моніторингу та дослідження потенційно лавинонебезпечних територій, а також для визначення локалізації стартових зон лавин та прогнозування напряму їх руху. Створено цифрову модель рельєфу частини Чорногірського хребта. Виконано візуалізацію стартових зон виникнення снігових лавин двох типів – лійкоподібних, або лоткових та площинних. Створено також тривимірну модель рельєфу, яка візуалізує рельєф, дає його наочне об'єктивне зображення. На ній добре видно основні форми рельєфу, напрямки хребтів, долин, а також місця зародження лоткових і площинних лавин. Порівняно з картою, інформативність зображення рельєфу значно вища. Використання такої 3D-моделі рельєфу дає змогу ще наочніше побачити місця можливого виникнення лавин і спрогнозувати напрям їх руху. Проведені дослідження дають змогу виконувати візуалізацію, наочне представлення лавинонебезпечних ділянок та місць можливого зародження лавин, створювати моделі розвитку лавинних процесів залежно від метеорологічних, ботанічних і морфометричних факторів. Результати досліджень є перспективними для туристичної та рекреаційної галузей, оскільки можуть бути використані у проектуванні туристичних маршрутів, будівництві об'єктів рекреації та для прогнозування виникнення снігових лавин.

GIS digital mapping of flood hazard in Jeddah–Makkah region from morphometric analysis

Floods are considered to be one of the natural disasters that seriously affect people’s lives and property every year. Although, delineation and determination of hydrologic basins and their morphometric parameters are difficult morphological tasks, GIS-based approach simplifies the investigation of various morphometric factors and helps to explore the correlation between the drainage morphometry and landform properties. The present study is aimed to investigate the spatial distribution of drainage basins around Jeddah–Makkah region and its surrounding areas (nearly 40,247 km2) using GIS spatial analysis. The morphometric parameters of these drainage basins and their channel systems were estimated and calculated. The computed morphometric parameters are categorized into the following three main groups: linear, aerial, and relief features. The documentation of these parameters was, then, used to evaluate and construct flood hazard map of the region. Flood hazard map assesses five classes with varying degrees (very low, low, moderate, high, and very high) of flood hazard zones. Such hydrological hazard is mostly due to the basin’s area and its highest relief ratio, relative relief, and ruggedness factor. The flood hazard map shows that the city of Jeddah is in a moderate to high flood hazard zone, but most of the areas surrounding it are in moderate flood hazard zone. This indicates that during heavy rainfalls, flash flood could be generated in these areas which can be severely affecting the city. In addition, this study shows a remarkable correlation between theoretical concepts, data sets, and field observations, predominantly highlighting the role of geology and geomorphology in influencing the basin morphometry and identity.

Morphometric analysis of watershed using remote sensing and GIS—a case study of Nanganji River Basin in Tamil Nadu, India

Morphometric analysis of a river basin is essential to identify and assess seasonal changes in drainage basin characteristics, understand the groundwater potential, and address issues related to management of soil erosion due to flash floods during the high flows. Nanganji River Basin is one of the least studied seasonal river basins in India which carry substantial flows during the monsoon period. In this study, morphometry of Nanganji River Basin, located in the central Tamil Nadu prairies, has been studied using remote sensing and GIS. The interrelationship between the various morphometric factors of the basin has been studied using a correlation matrix. Factor analysis has been applied to group the individual morphometric parameters into a smaller number of factors. Further, these factors have been studied in relation to the sub-basins to understand the existing relation between the factors and the sub-basins. Finally, the study identifies environmental issues of the Nanganji River Basin mostly related to the river flow regime which widens significantly during the monsoon months.

Analysis of the relationship between the morphology of the palate and facial skeletal patterns in Class III malocclusion using structural equation modelling.

The present study investigated the relationship between facial skeletal patterns and morphology of the palate in adult patients with Class III malocclusion using structural equation modelling (SEM). One hundred cone beam computed tomography images of Class III adults were evaluated for skeletal measurements. The skeletal measurements were classified into the vertical, anteroposterior and transverse group based on factor analysis. 3D scanning model of the maxilla was analysed by Generalized procrustes analysis (GPA) and principal component analysis (PCA). Structural equation modelling was used to analyse relationship among the skeletal and morphometric factors. According to the factor analysis, latent variables were extracted by each skeletal variable. First principal component (PC1) and PC2 of palatal morphology were used to analyse relationship with skeletal variables. As results of the structural equation model, the transverse latent variable had the most influence on PC1, followed by vertical and anteroposterior variables. This result means that as the facial width increases, the palate becomes narrower, deeper and longer. The relationship between the skeletal pattern with Class III malocclusion and palatal morphology was analysed through SEM. The transverse facial skeletal pattern showed the highest correlation with PC1 of palatal morphology.

Evaluation of population parameters and biometric data of an Eurasian Collared Dove (Streptopelia decaocto Friv.) population in the Great Plain of Hungary

The Eurasian Collared Dove shows different patterns in density all over Hungary. In some cases, the population has decreased to a lower level, but there are habitats where the population remained stable. Several factors were taken into consideration during the evaluation of this phenomenon. These publications state that the increased urbanization of corvids, the lack of food sources, and the changes in nesting sites caused the decrease in numbers. During our research, we intend to contrast the differences in population structure of Collared Doves that differ from each other in the density of predators presented at nesting sites. As a first step, in this paper, numerous samples (n=118) were taken from a population that is less influenced by corvid species’ nest predation. Our prediction was that the population parameters remained at the level of 1980’s, in which the population of Eurasian Collared Dove has reached its maximum, according to further publications.
 During the evaluation process, our data were collected from hunting bags near Nyíregyháza. Results were compared with former publications. We stated that the population structure, such as age and gender distribution remained stable in the evaluated population. In addition, morphometric factors of the collected individuals were also measured, such as weight, wing length, 3rd primary feather, and tail length, which were compared with former surveys. During statistical tests no significant difference was revealed among population parameters, but there were significant differences between most of the morphometric data, (p>0.05).

Climate warming response of mountain lakes affected by variations in snow

AbstractOur objectives were to determine how temperatures in mountain lakes respond to changes in climate and to characterize how their responses are mediated by landscape or lake morphometric factors. Our analysis combines the use of high‐frequency climate and lake temperature data from 1983 to 2016 in a high‐elevation catchment in the Sierra Nevada of California with summer water temperature data from a set of 18 additional lakes scattered throughout the range. Average annual air temperatures warmed at 0.63°C decade−1, but variation in lake temperature was driven primarily by amount of precipitation as snow. By regulating the duration of ice cover and volume of inflowing spring snowmelt, variation in snowpack size accounted for 93% of variation in summer epilimnetic temperatures. The effect of snow on lake temperatures was mediated by variation in elevation and lake depth at landscape scales, creating a predictable mosaic of lake sensitivities to climate warming.

Morphometric characteristics and condition factor of <i>Chrysichthys nigrodigitatus</i> (Lacepede, 1803) and <i>Sarotherodon melanotheron</i> (Ruppell, 1852) in the Lagos Lagoon

One hundred and fifty (150) specimens of Sarotherodon melanotheron and 150 specimens of Chrysichthys nigrodigitatus were collected from Better-life Fish Market in Makoko area of Lagos State between June-August 2016 to provide information on the size distribution, length-weight relationship, determine regression equation and coefficient of determination of morphometric parameters and condition factor of the species. Size ranges of 10-22 cm and 15-33 cm were observed in S. melanotheron (20-158 g) and C. nigrodigitatus (30-279 g) respectively. Length-weight relationship of S. melanotheron and C. nigrodigitatus were described by the equation Log W = -1.107 + 2.4478 Log L and Log W = -1.9287 + 2.8484 Log L respectively. The b values (growth exponent), 2.4478 and 2.8484 for body weight on total length of S. melanotheron and C. nigrodigitatus respectively indicate negative allometric growth which implies that the fishes become slenderer as they increase in weight. The least coefficient of determination (r2), 0.4305 (S. melanotheron) and 0.2221 (C. nigrodigitatus) were obtained in snout length on total length and pelvic fin length on total length respectively. High values coefficient of determination, obtained indicates a high degree of positive correlation between the different morphometric parameters with the reference length (total length). All mean condition factors (k) calculated for species, size classes and sexes are all above 1 and this reveals that they are all in good conditions and that the environment is suitable for both species with regards to the feeding condition. This study provides some biological information on the condition of the species in the Lagos Lagoon as at the period of the study.Keywords: Morphometric characteristics; condition factor; Chrysichthys nigrodigitatus; Sarotherodon melanotheron; Lagos Lagoon.

PCA (Principal Component Analysis) application to differentiate hybrid and pure black-winged myna (Acridotheres melanopterus)

Black-winged myna (Acridotheres melanopterus) is an endemic bird of Java and Bali that is currently critically endangered based on International Union of Conservation for Nature (IUCN) since 2010. Hybridization in captivity occurs between the Acridotheres melanopterus with other species of myna. It is difficult to distinguish hybrid and pure black-winged myna without thorough observation. The study was conducted to determine the differences between hybrid and pure black-winged myna based on the morphometric characteristics using Principal Component Analysis (PCA). The samples were selected using purposive sampling method at Cikananga Conservation Breeding Center located in Sukabumi, West Java in May 2017. The morphometric data were taken directly from 44 black-winged mynas with > = 2 years old. Data collection was done by measuring body length, body width, body circumference, span of wings and weight. The morphometric data were analyzed by PCA using the SPSS V.20 program. The results showed that body circumference and wing span were the morphometric factors which the most distinguish between them with eigenvalue of 0.943 and 0.811 respectively. In addition, the existence of morphological anomalies is also a sign that the black-winged mynas are hybrids.

Groundwater spring potential modelling: Comprising the capability and robustness of three different modeling approaches

Sustainable water resources management in arid and semi-arid areas needs robust models, which allow accurate and reliable predictive modeling. This issue has motivated the researchers to develop hybrid models that offer solutions on modelling problems and accurate predictions of groundwater potential zonation. For this purpose, this research aims to investigate the capability and robustness of a novel hybrid model, namely the logistic model tree (LMT) and compares it with state-of-the-art models such as the support vector machine and C4.5 models that locate potential zones for groundwater springs. A spring location dataset consisting of 359 springs was provided by field surveys and national reports and from which three different sample data sets (S1–S3) were randomly prepared (70% for training and 30% for validation). Additionally, 16 spring-related factors were analyzed using regression logistic analysis to find which factors play a significant role in spring occurrence. Twelve significant geo-environmental and morphometric factors were identified and applied in all models. The accuracy of models was evaluated by three different threshold-dependent and –Independent methods including efficiency (E), true skill statistic (TSS), and area under the receiver operating characteristics curve (AUC-ROC) methods. Results showed that the LMT model had the highest accuracy performance for all three validation datasets (Emean = 0.860, TSSmean = 0.718, AUC-ROCmean = 0.904); although a slight sensitivity to change in input data was sometimes observed for this model. Furthermore, the findings showed that relative slope position (RSP) was the most important factor followed by distance from faults and lithology.

Improving landslide susceptibility mapping using morphometric features in the Mawat area, Kurdistan Region, NE Iraq: Comparison of different statistical models

Susceptibility mapping provides information about vulnerable locations and thus helps to potentially decrease infrastructure damage due to mass wasting. During the past decades, expansion of settlements into areas prone to landslides in Iraq has highlighted the importance of accurate landslide susceptibility studies. The main goal of this research is to implement selected morphometric parameters to improve prediction of landslide susceptibility in the Zagros Mountain region. We used the Mawat area, in the Kurdistan Region (NE Iraq) to test the added value of morphometric indicators. Sixteen morphometric factors, mainly derived from a Digital Elevation Model (DEM), extracted using the stereo-ability of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) satellite, as well as geological and environmental predictive factors, were appraised. We evaluated and compared Frequency Ratio (FR), Weight of Evidence (WOE), Logistic Regression (LR) and Probit Regression (PR) approaches in combination with morphometric indices to determine the Landslide Susceptibility (LS). The areas under the curve (AUC) of the Prediction Rate Curve (PRC), Relative landslide density Index (R index), and True Positive Percentage (TPP) for the four models show that all models perform similarly, and the focus should be on careful selection of the predictive factors, which is far more important than the methods used. Results indicate that lithology and slope aspects are the more dominant factors that lead to detect possible occurrence of landslides. Furthermore, this work demonstrates that the hypsometric integral performs better than the commonly used slope curvature as a predictor and thus increases the prediction accuracy of the susceptibility map. We argue that the use of adequate morphometric parameters can increase the efficiency of the LS mapping in other regions of the world.

Mechanical Strength of the Proximal Femur After Arthroscopic Osteochondroplasty for Femoroacetabular Impingement: Finite Element Analysis and 3-Dimensional Image Analysis

To examine the influence of femoral neck resection on the mechanical strength of the proximal femur in actual surgery. Eighteen subjects who received arthroscopic cam resection for cam-type femoroacetabular impingement (FAI) were included. Finite element analyses (FEAs) were performed to calculate changes in simulative fracture load between pre- and postoperative femur models. The finite element femur models were constructed from computed tomographic images; thus, the models represented the shape of the original femur, including the bone resection site. Three-dimensional image analysis of the bone resection site was performed to identify morphometric factors that affect strength in the postoperative femur model. Four oblique sagittal planes running perpendicular to the femoral neck axis were used as reference planes to measure the bone resection site. At the transcervical reference plane, both the bone resection depth and the cross-sectional area at the resection site correlated strongly with postoperative changes in the simulated fracture load (R2= 0.6, P= .0001). However, only resection depth was significantly correlated with the simulated fracture load at the reference plane for the head-neck junction. The resected bone volume did not correlate with the postoperative changes in the simulated fracture load. The results of our FEA suggest that the bone resection depth measured at the head-neck junction and transcervical reference plane correlates with fracture risk after osteochondroplasty. By contrast, bone resection at more proximal areas did not have a significant effect on the postoperative femur model strength in our FEA. The total volume of resected bone was also not significantly correlated with postoperative changes in femur model strength. This biomechanical study using FEA suggest that there is a risk of femoral neck fracture after arthroscopic cam resection, particularly when the resected lesion is located distally.

Correlation between the severity of myelopathy and cervical morphometric parameters on dynamic magnetic resonance imaging.

To compare morphometric factors of cervical spine in the cervical stenosis on dynamic and static magnetic resonance imaging. To analyse the relationship between the severity of myelopathy and morphometric parameters. Patients with cervical canal stenosis scanned with MRI in neutral (N), flexion (F) and extension (E) positions were retrospectively reviewed. All cases were evaluated in Nurick and Muhle grades. Following parameters were measured: anterior and posterior length of the cervical cord (aLCC, pLCC), mid-cord distance (L value), cervical cord angle (CCA), cervical lordosis, spine/cord (S/C) angle ratio, spinal cord (SC) area, cerebrospinal fluid (CSF) area, and CSF reserve ratio (CSF/CSF plus SC). Univariate multiple regression for Nurick grade as dependent factor was used. Sixty-three patients and 34 men, with the mean age of 58.2 ± 11years, were analysed. Significant differences were found for pLCC, SC area, C lordosis and CCA. The difference between F and E for C lordosis angle was 42.80° ± 14.4 and for CC angle 30.42° ± 9.6. The mean S/C angle ratio was calculated for 1.4 ± 1.3. Nurick grade positively correlated with age (p = 0.041) and S/C angle ratio (p = 0.011), negatively with SC area (p = 0.006) and flexion-extension difference of L value (0.004). Severity of myelopathy correlates with age, spinal cord area on extension and reduced mobility of spinal cord. An association between spine/cervical cord angle mismatch and Nurick grade was found.

Associations between Macrophyte Life Forms and Environmental and Morphometric Factors in a Large Sub-tropical Floodplain.

Macrophyte assemblages are composed of species with different life forms and various ecological functions. Our aim was to investigate the potential environmental determinants of changes in the biomass of individual life forms and of the composition of the macrophyte assemblage in terms of life forms diversity. We sampled 23 waterbodies at low and high water levels in the Middle Paraná River floodplain. Macrophyte biomass samples were collected and classified in terms of life forms. We performed a redundancy analysis using the biomass of the various life forms to assess the importance of environmental variables to the composition of macrophyte life forms. Linear regressions were applied to investigate the environmental determinants of the biomasses of individual life forms. The degree of connectivity and the combination of depth, hydrology and nitrate were the main determinants of the composition in terms of life forms. The biomass of each individual life form was explained by different combinations of environmental variables, but the connectivity was the most important one. Our study shows that groups of species with similar life forms respond to environmental factors in particular ways, which might alter the biomass composition of life forms. Given that the ecosystem functioning depends on the functional characteristics of local communities, our findings about the relation between environmental changes and the community composition in terms of life forms (or functional composition) can be a helpful tool for predicting changes on ecosystem processes (such as nutrient cycling) against possible future scenarios.

A neural network model applied to landslide susceptibility analysis (Capitanejo, Colombia)

The generation of landslide present in the municipality of Capitanejo (Santander-Colombia) is conditioned to lithological, structural and morphometric factors that are related to the climatic activity. These factors describe a pattern of instability in the rocks, which generates falls, slides and flows. These conditions are seen in the results of a neural network model generated with the backpropagation algorithm. This model presented the conditions of the study area evaluated by the degree of susceptibility to landslide. The model predicted 92.86% of the data that were not entered in the learning module, which represents 50% of the landslides mapped in the region. This simulation generates different levels of susceptibility to landslide from very low to very high. In the study area, a tendency for moderate to very high susceptibility to landslides was found for the margins of the Chicamocha river valley. In turn, this area presents the largest number of active processes (falls and flows), which generates a problem that affects several levels within the sectors of production, communication and infrastructure of the community of Capitanejo.

Bivariate statistical index for landslide susceptibility mapping in the Rorachu river basin of eastern Sikkim Himalaya, India

The main goal of the study is to prepare a landslide susceptibility map under Geographical Information System (GIS) environment using statistical index model to identify and demarcate the areas of future landslide occurrence. Firstly, landslide locations were identified with the help of previous reports, satellite images and intensive field study. For the preparation of landslide inventory, 80 landslide locations were identified and randomly separated to create training and validation datasets. Fifty landslides (62.5%) were used as training dataset and remaining 30 landslides (37.5%) were used for validating the model. Twelve landslide conditioning factors, including morphometric factors (slope angle, slope aspect, curvature, relative relief and drainage density) and non-morphometric factors (bedrock geology, soil, distance from drainage, distance from lineament, distance from road, Normalized Difference Vegetation Index (NDVI) and land use/land cover), were used to generate landslide susceptibility map of Rorachu river basin. Finally, the accuracy of the model was assessed by area under curve of Receiver Operating Characteristics (ROC) curve and landslide density method. The statistics of ROC curve showed that, the landslide susceptibility map using statistical index model has an accuracy of 91% which indicates a very good predictive capacity of the model. The result reveals that, landslide density of the Rorachu river basin is increasing with landslide susceptibility classes.

Morphometric characterization of the Igarapé Carrapato river basin, Boa Vista, Roraima

O manejo de bacias hidrográficas baseia-se em um conjunto de técnicas aplicadas com o objetivo de regularizar a vazão dos cursos hídricos, a produção econômica e a proteção ambiental, garantindo a preservação da biodiversidade. O presente estudo tem como objetivo determinar as características morfométricas da bacia hidrográfica do Igarapé Carrapato, Boa Vista/Roraima. Inicialmente foi obtido o Modelo Digital de Elevação, e com base nele a bacia foi delimitada. Posteriormente foram calculados alguns parâmetros morfométricos para o estudo do comportamento hidrológico da bacia. A bacia em estudo, com base na análise dos fatores morfométricos analisados, apresenta baixa susceptibilidade a enchentes.

Coastal Risk and Water Flow Analysis in Eastern Algeria (Western Mediterranean)

In this paper, we present the combination of tsunami modelling studies with a GIS approach to analyse the coastal flooding risk in eastern Algeria. The Jijel and Bejaia regions are well-known for their seismic and tsunami risk. The modelling was carried out with the Geoclaw software. It provided the water flow velocities in addition to water heights results for several points of interest located between the Bejaia and the Jijel coast. The simulations were based on a 7.6 magnitude earthquake offshore the Jijel bay. Maps visualizing the susceptibility to flooding were generated in ArcGIS using the GIS integrated weighted overlay tools. By aggregating and weighting morphometric factors (such as the lowest height levels and lowest slope gradients) influencing the susceptibility to flooding the coastal areas prone to inundations in case of high energetic flood waves (tsunami, storm surge, meteo .tsunami) from the sea side can be determined. The entrances of river mouths are the locations marked by the highest susceptibility to potential flooding.

Impact of bifurcation angle and inflow coefficient on the rupture risk of bifurcation type basilar artery tip aneurysms.

OBJECTIVE Risk factors for aneurysm rupture have been extensively studied, with several factors showing significant correlations with rupture status. Several studies have shown that aneurysm shape and hemodynamics change after rupture. In the present study the authors investigated a static factor, the bifurcation angle, which does not change after rupture, to understand its effect on aneurysm rupture risk and hemodynamics. METHODS A hospital database was retrospectively reviewed to identify patients with cerebral aneurysms treated surgically or endovascularly in the period between 2008 and 2015. After acquiring 3D rotational angiographic data, 3D stereolithography models were created and computational fluid dynamic analysis was performed using commercially available software. Patient data (age and sex), morphometric factors (aneurysm volume and maximum height, aspect ratio, bifurcation angle, bottleneck ratio, and neck/parent artery ratio), and hemodynamic factors (inflow coefficient and wall shear stress) were statistically compared between ruptured and unruptured groups. RESULTS Seventy-one basilar tip aneurysms were included in this study, 22 ruptured and 49 unruptured. Univariate analysis showed aspect ratio, bifurcation angle, bottleneck ratio, and inflow coefficient were significantly correlated with a ruptured status. Logistic regression analysis showed that aspect ratio and bifurcation angle were significant predictors of a ruptured status. Bifurcation angle was inversely correlated with inflow coefficient (p < 0.0005), which in turn correlated directly with mean (p = 0.028) and maximum (p = 0.014) wall shear stress (WSS) using Pearson's correlation coefficient, whereas aspect ratio was inversely correlated with mean (0.012) and minimum (p = 0.018) WSS. CONCLUSIONS Bifurcation angle and aspect ratio are independent predictors for aneurysm rupture. Bifurcation angle, which does not change after rupture, is correlated with hemodynamic factors including inflow coefficient and WSS, as well as rupture status. Aneurysms with the hands-up bifurcation configuration are more prone to rupture than aneurysms with other bifurcation configurations.