scholarly journals Impact of cliff erosion on marine sediment composition - indication of local coastline evolution (Vrgada Island, Croatia)

2020 ◽  
pp. 462-468
Author(s):  
Kristina Pikelj ◽  
Nina Furčić
Keyword(s):  
Marine Sediment ◽  
Surface Sediment ◽  
Sediment Samples ◽  
Eastern Side ◽  
Coastline Evolution ◽  
Longshore Drift ◽  
First Results ◽  
Coastal Cliffs ◽  
Northern Side ◽  
The One

Erosive coastal cliffs formed in soft-rocks sediments along the generally carbonaceous Eastern Adriatic are a rare feature. The one from the Vrgada Island gave rise to the idea that local seabed surface sediment may reflect the composition of the cliff sediment. First results of sedimentological analyses showed that sediment samples collected on both sides of the cliff contain material eroded mostly from the eastern side of the cliff. Subsequent longshore drift caused by dominant waves likely sort fallen material, transporting its finer fractions to the northern side and further into the sea.

Particle Size Effects on Concentration of Metals in Lake Erie Bottom Sediments

1984 ◽  
Vol 19 (1) ◽  
pp. 27-36 ◽  
Author(s):  
Alena Mudroch
Keyword(s):  
Particle Size ◽  
Organic Matter ◽  
Clay Minerals ◽  
Surface Sediment ◽  
Size Effects ◽  
Lake Erie ◽  
Size Fraction ◽  
Mineralogical Composition ◽  
Major Elements ◽  
Sediment Samples

Abstract Surface sediment samples obtained at the offshore and nearshore area of Lake Erie were separated into eight different size fractions ranging from <2 µm to 250 µm. The concentration of major elements (Si, Al, Ca, Mg, K, Na, Fe, Mn and P), metals (Zn, Cu, Cr, Ni, V, Co and Pb) and organic matter was determined together with the mineralogical composition and morphology of the particles in each size fraction. The distribution of the metals in the offshore sediment was bimodal with the majority of the metals divided between the 63 to 250 um size fraction which also contained the highest concentration of organic matter (about 20%) and the <4 µm fraction containing up to 60% of clay minerals. However, the metals in the nearshore sediment were associated mainly with the clay minerals.

scholarly journals Knetex – Development of a textile-integrated sensor system for feedback-supported rehabilitation after surgery of the anterior cruciate ligament

2020 ◽  
Vol 6 (3) ◽  
pp. 368-371
Author(s):  
Julia Demmer ◽  
A. Kitzig ◽  
N. Schlage ◽  
G. Stockmanns ◽  
E. Naroska
Keyword(s):  
Anterior Cruciate Ligament ◽  
Cruciate Ligament ◽  
Sensors And Actuators ◽  
Integrated Sensor ◽  
Rehabilitation Process ◽  
Active User ◽  
Smart Textile ◽  
First Results ◽  
Anterior Cruciate ◽  
The One

AbstractPatients often report an effect after surgery of the anterior cruciate ligament which is called "giving way". This manifest itself by a drop of the knee or a felt instability. This phenomenon is difficult to measure and validate because it usually does not occur regularly and is not reproducible under laboratory conditions. The Knetex project takes up this point by trying to actively support the rehabilitation process with a bandage that can be worn in everyday life and is constructed as a smart textile using sensors and actuators. For this purpose, on the one hand it is attempted to actively record the phenomenon of the "giving way" by measuring knee angles etc. and by active user feedback. At the same time, the patient is specifically advised by means of actuators to correct incorrect posture or movement in order to make the rehabilitation process more effective and prevent further damage. Two 9-axis IMUs (inertial measurement units) form the basis of the system. These are used together with a textile strain sensor to calculate the knee angles. This paper gives an overview of the planned system, the initial experiments to measure the knee angles and the first results of the actuator study.

scholarly journals Validation of an analytical methodology for the quantitative analysis of petroleum hydrocarbons in marine sediment samples

Química Nova ◽  
2009 ◽  
Vol 32 (4) ◽  
pp. 855-860 ◽  
Author(s):  
Eloy Yordad Companioni Damas ◽  
Miriam Odette Cora Medina ◽  
Ana Catalina Núñez Clemente ◽  
Miguel Ángel Díaz Díaz ◽  
Luis González Bravo ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
Marine Sediment ◽  
Petroleum Hydrocarbons ◽  
Analytical Methodology ◽  
Sediment Samples

scholarly journals Digital Governance of Moroccan School Establishments

2021 ◽  
pp. 348-355
Author(s):  
Abderrazak Mazouak ◽  
Malika Tridane ◽  
Said Belaaouad
Keyword(s):  
Research Work ◽  
Project Planning ◽  
Pedagogical Practices ◽  
Third Phase ◽  
First Results ◽  
On Line ◽  
The One ◽  
Traditional Paradigm ◽  
And Control ◽  
Relationship Of

Digital technologies have come to shake up the traditional paradigm of learning, and to change the existing relationship of "know-teaching" to put in place a key concept of the time is "to accompany through digital tools Our intervention is part of a technical-pedagogical approach and will focus on an action research work in which we will try:First, to present on line an accessible digital device that facilitates and organizes project planning and provides means to govern and control the quality of administrative acts.Next, We will show the first results of the experimentation of this tool in our context of research represented by 355 directors of the secondary schools of the provincial delegation of Taza. Morocco, pointing out all the constraints and limitations that hampered its implementation.Finally, we confirm that the use of this device by our sampling has caused a triple effect on their pedagogical practices: the professionalization of strategic planning on the one hand, and the governance of resources and the rationalization of pedagogical decisions on the other hand and immediate evaluation and regulation in the third phase.

scholarly journals Physio-chemical properties and dynamic of the surface sediment in riparian mangroves along the Tien river, Tien Giang province

2019 ◽  
Vol 2 (5) ◽  
pp. 50-58
Author(s):  
Hung Duc Nguyen ◽  
Ngot Van Pham ◽  
Duy Van Nguyen
Keyword(s):  
Electrical Conductivity ◽  
Organic Matter ◽  
Surface Sediment ◽  
Chemical Properties ◽  
Total Sulfur ◽  
Mean Sea Level ◽  
Factors Affecting ◽  
Sediment Samples ◽  
Mesohaline Zone ◽  
Saturated Extract

This study was conducted to investigate the physio-chemical properties and vertical dynamic of the surface sediment (0–5 cm) in riparian mangroves along the Tien river, Tien Giang province. The distribution of riparian mangroves located from the polyhaline zone (transect S1 and S2) to the mesohaline zone (transect S3 and S4) and the oligohaline zone (transect S5). Three plots (10x10 m) per transect were set based on the elevation of the mangrove floor (cm + mean sea level) and dominant plants. A total of 28 sediment samples were collected in December 2016 and April 2017. Seasonal variation of pH, redox potential (Eh), electrical conductivity of saturated extract (ECse), bulk density, sediment organic matter (SOM) and total sulfur (TS) were measured in accordance with the standard protocols. Seasonal trends of vertical erosion and accumulation were tested by the tracer stick method. The ECse values and TS concentrations were higher in the dry season and in transects closed to the estuary (S1, S2 and S3) but these trends weren’t found for pH, Eh, and SOM. In most of the riparian mangroves along the Tiền river, low elevation (0–50 cm) was one of important factors affecting the Eh and ECse. In the rainy season, major changes in vertical erosion and acumulation have occurred in the transects near the mouth of the river.

scholarly journals Sediment Sources and Dispersion on the Western Sunda Shelf, Malay Peninsula, Southern South China Sea

Water ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 2823
Author(s):  
Yanguang Liu ◽  
Chuanshun Li ◽  
Ramlan Bin Omar ◽  
Xuefa Shi ◽  
Hui Zhang ◽  
...  
Keyword(s):  
Grain Size ◽  
Surface Sediment ◽  
Surface Sediments ◽  
The Other ◽  
Coarse Grained ◽  
Malay Peninsula ◽  
Sediment Sources ◽  
Southern South China Sea ◽  
Sunda Shelf ◽  
Sediment Samples

Thirty-nine surface sediment samples collected from the western Sunda Shelf off the Malay Peninsula (WSSMP) in the southern South China Sea (SCS) were analysed for grain size, major and trace elemental compositions, and light/heavy mineral contents to trace the sediment sources and their transport mechanisms in the study area. In the WSSMP, the surface sediments are relatively poorly sorted but transportable. A principal component analysis of 37 elements and grain size fractions indicates that the surface sediments can be grouped into four major assemblages in the study area. Integrating with the light/heavy minerals data in the 63–125 μm fractions of the surface sediment samples, to better trace the sediment sources of the coarse-grained components in the marine environment, the study area can be further divided into four sediment provinces. Province I is located in the northwestern part of the study area. The concentrations of TiO2, Na2O, garnet, siderite, and glauconite in Province I were higher than in the other provinces. The main sediment source for this province originated from the Kelantan River and the Gulf of Thailand transported by the northeastern monsoon current. Province II is located offshore of the Pahang and Endau Rivers. The percentages of TiO2, rare earth elements, Al2O3, quartz, plagioclase, hypersthene, and magnetite in the surface sediments were typically higher in this province than in the other provinces. The Pahang and Endau rivers provide most of the sediments to this province, which are transported by southward coastal currents. Province III is located in the northeastern and eastern parts of the study area, where the coarse-grained sediment fraction had relatively high hornblende and biotite contents. Sediments in this province are mostly transported from the Mekong River during the northeastern monsoon. The other parts of the study area belong to Province IV, where the surface sediment elemental and mineral concentrations were mostly between those of the other three provinces. Therefore, we suggest that Province IV has a mixed source due to inputs from the surrounding rivers.

scholarly journals The Southern Ocean Radiolarian (SO-RAD) dataset: a new compilation of modern radiolarian census data

2021 ◽  
Vol 13 (11) ◽  
pp. 5441-5453
Author(s):  
Kelly-Anne Lawler ◽  
Giuseppe Cortese ◽  
Matthieu Civel-Mazens ◽  
Helen Bostock ◽  
Xavier Crosta ◽  
...  
Keyword(s):  
Species Diversity ◽  
Data Collection ◽  
Southern Ocean ◽  
Marine Sediments ◽  
Surface Sediment ◽  
Census Data ◽  
Reference Dataset ◽  
Past Climate ◽  
Sediment Samples ◽  
Comprehensive Reference

Abstract. Radiolarians (holoplanktonic protozoa) preserved in marine sediments are commonly used as palaeoclimate proxies for reconstructing past Southern Ocean environments. Generating reconstructions of past climate based on microfossil abundances, such as radiolarians, requires a spatially and environmentally comprehensive reference dataset of modern census counts. The Southern Ocean Radiolarian (SO-RAD) dataset includes census counts for 238 radiolarian taxa from 228 surface sediment samples located in the Atlantic, Indian, and southwest Pacific sectors of the Southern Ocean. This compilation is the largest radiolarian census dataset derived from surface sediment samples in the Southern Ocean. The SO-RAD dataset may be used as a reference dataset for palaeoceanographic reconstructions, or for studying modern radiolarian biogeography and species diversity. As well as describing the data collection and collation, we include recommendations and guidelines for cleaning and subsetting the data for users unfamiliar with the procedures typically used by the radiolarian community. The SO-RAD dataset is available to download from https://doi.org/10.1594/PANGAEA.929903 (Lawler et al., 2021).

Dimensionality and Construct Validity of a Video-Based, Objective Personality Test for the Assessment of Willingness to Take Risks in Road Traffic

2005 ◽  
Vol 97 (1) ◽  
pp. 309-320 ◽  
Author(s):  
Martin E. Arendasy ◽  
Andreas Hergovich ◽  
Markus Sommer ◽  
Bettina Bognar
Keyword(s):  
Construct Validity ◽  
Personality Trait ◽  
Road Traffic ◽  
Personality Test ◽  
Traffic Situation ◽  
One Dimensional ◽  
First Results ◽  
The One ◽  
The Given ◽  
Homeostasis Theory

The study at hand reports first results about the dimensionality and construct validity of a newly developed objective, video-based personality test, which assesses the willingness to take risks in traffic situations. On the basis of the theory of risk homeostasis developed by Wilde, different traffic situations with varying amounts of objective danger were filmed. These situations mainly consisted of situations with passing maneuvers and speed choice or traffic situations at intersections. Each of these traffic situations describes an action which should be carried out. The videos of the traffic situations are presented twice. Before the first presentation, a short written explanation of the preceding traffic situation and a situation-contingent reaction is provided. The respondents are allowed to obtain an overview of the given situations during the first presentation of each traffic situation. During the second presentation the respondents are asked to indicate at which point the action that is contingent on the described situation will become too dangerous to carry out. Latencies for items were recorded as a measure for the magnitude of the person's subjectively accepted willingness to take risks in the sense of the risk homeostasis theory by Wilde. In a study with 243 people with different education and sex, the one-dimensionality of the test corresponding to the latency model by Scheiblechner was investigated. Analysis indicated that the new measure assesses a one-dimensional latent personality trait which can be interpreted as subjectively accepted amount of risk (target risk value). First indicators for the construct validity of the test are given by a significant correlation with the construct-related secondary scale, adventurousness of the Eysenck Personality Profiler with, at the same time, nonsignificant correlations to the two secondary scales, extroversion and emotional stability, that are not linked to the construct.

Reconstructing provenance changes in sediments supplying the South East African margin

2021 ◽  
Author(s):  
Ellie Pryor ◽  
Ian Hall ◽  
Morten Andersen ◽  
Daniel Babin ◽  
Yue (Merry) Cai ◽  
...  
Keyword(s):  
South African ◽  
Marine Sediment ◽  
River Sediment ◽  
Middle Stone Age ◽  
Source Rocks ◽  
Drainage Basins ◽  
Sediment Samples ◽  
Terrigenous Sediment ◽  
Geological Unit ◽  
Spatial Coverage

<div> <p>Sediment provenance is of key importance for understanding transport history and characterising sediment source regions in the marine and terrestrial environment. Radiogenic isotopes are widely used to identify inland and coastal sediment origins. They document changes in detrital terrigenous sediment fluxes which can be related to continental hydrological variability. Understanding sediment sources to the ocean is a pre-requisite before interpreting past climate archives in marine sediment cores.</p> </div><div> <p><span>South African coastal drainage basins are composed of various geological units, each reflected by different radiogenic isotope signals in the sediment. In addition to the age and nature of their source rocks, the sediment type influences this radiogenic signature.</span></p> </div><div> <p><span>Here, we present a review of the present-day radiogenic isotopic fingerprints of South African river catchments signals from new river sediment samples with the aim to gain a broad spatial coverage of the source rocks in the region and their relative contributions of terrigenous sediment delivered to the ocean. This information will be applied to marine sediment core MD20-3591 (36° 43.707 S; 22° 9.151 E, water depth 2464m), located offshore South Africa which has the potential to record both Agulhas Current and terrestrial variability. The core site receives a significant amount of terrigenous material from the African continents via riverine input. During the last glacial period, these rivers flowed across the continental shelf within a subdued incised valley. The Gourritz River catchment drains the Cape Supergroup and Karoo Supergroup, typical of these southern drainage basins, whereas the eastern Cape rivers drain the Karoo Supergroup geological unit which is capped by the Drakensberg basalts.</span></p> </div><div> <p><span>We are using the knowledge gained from these new South African terrestrial river sediment samples to identify the sources and transport pathways of the terrigenous sediments in MD20-3591. Of particular interest is the sensitivity of the radiogenic isotopic signatures to grain size variabilities and how this relationship can help to define local or distal sediments. These records will allow us to explore variability in regional hydroclimate in relation to the abundant archaeological evidence of cultural and technological innovations of Middle Stone Age humans in southern Africa.</span></p> </div>

Sign in / Sign up

Export Citation Format

Share Document