scholarly journals Evolution of Near-Shore Outwash Fans and Permafrost Spreading Under Their Surface: A Case Study from Svalbard

2020 ◽  
Vol 12 (3) ◽  
pp. 482 ◽  
Author(s):  
Marek Kasprzak ◽  
Michał Łopuch ◽  
Tadeusz Głowacki ◽  
Wojciech Milczarek

The article presents geomorphological analysis results for two outwash fans (sandurs), Elveflya and Nottingham, in the marginal zone of the Werenskiold Glacier in the south-west part of the Spitsbergen. The main goal of this study was to reconstruct the morphological evolution of these landforms and to identify the permafrost zone under their surface. For this purpose, age data of fossils were compiled and compared with newly exposed and dated fossil tundra in the layer glaciotectonically deformed by the forming glacier end moraine. Using this method, a time frame was identified for the glacier advance and for the simultaneous formation of the outwash plains. It was concluded that the Elveflya surface has been built-up with deposits since the Little Ice Age. Sediment deposition ended in the late 1960s, due to hydrographic changes and the redirection of all proglacial waters towards the Nottingham bay. A photointerpretation analysis based on two orthophotomaps and LANDSAT scenes allowed the identification of five microfans in Elveflya, of which two youngest fans have a twice shorter range than the other three. The sixth microfan is currently shaped by deposits washed from the slope of the end moraine. An additional focus was placed on a currently active sandur, which fills the Nottingham bay, in order to identify its growth rate. The average growth rate of this surface increased from 5700 m2·year−1 over the period of 1985–2000 to 24,900 m2·year−1 over the period of 2010–2017. Electromagnetic measurements carried out on the surfaces of the sandurs demonstrated that the electrical resistivity of the ground is high in the apex of the Elveflya fan (ρ ≥ 1 kΩ.m) and low in its toe (typically ρ < 200 Ω.m), as in the case of the Nottingham fan ground. In the interpretation advanced here, permafrost developed in the proximal part of the Elveflya sandur, which continues to be supplied by fresh groundwaters flowing from the glacier direction. Low electrical resistivity of the ground in the distal part of the outwash fan suggests the absence of ground ice in this zone, which is subjected to the intrusion of salty and comparatively warm seawater, reaching approximately 1 km inland under the surface of the low-elevated marine terrace. The identified zones additionally display different tendencies for vertical movements of the terrain surface, as identified with the Small Baseline Subset (SBAS) method. The proximal part of the Elveflya outwash fan is relatively stable, while its distal part lowers in the summer period by a maximum of 5 cm. The resulting morphological changes include linear cracks having lengths up to 580 m and an arc line consistent with the coastline.

Author(s):  
Farida . ◽  
Eka Indah Raharjo ◽  
Arnis Maylinda Sari

ABSTRAKPenelitian bertujuan untuk mengetahui penggunaan fermentasi bungkil kelapa sawit dalam pakan buatan.Penelitian menggunakan Rancangan Acak Lengkap (RAL) yang terdiri dari 4 perlakuan 3 ulangan.Susunan perlakuan adalah Perlakuan A : bungkil kelapa sawit 12%, Perlakuan B : fermentasi bungkil kelapa sawit 15%, Perlakuan C : fermentasi bungkil kelapa sawit 18%, Perlakuan D : fermentasi bungkil kelapa sawit 21%. Penelitian ini dilakukan selama 60 hari untuk mengetahui laju pertumbuhan spesifikberat, laju pertumbuhan harianpanjang, konversi pakan, kelangsungan hidup dan kualitas air sebagai penunjang.Hasil penelitian menunjukkan pemberian pakan buatan dengan fermentasi bungkil kelapa sawit menghasilkan respon yang baik terhadap pertumbuhan ikan gurami. Pemberian pakan buatan dengan fermentasi bungkil kelapa sawit 18% (perlakuan C), memberikan hasil terbaik dengan laju pertumbuhan dengan rata – rata laju pertumbuhan spesifik berat 1.502%, laju pertumbuhan harian panjang 4.06%, nilai konversi pakan rata – rata 3.48 dan kelangsungan hidup rata – rata 90%.Kata Kunci : Fermentasi Bungkil Kelapa Sawit, Ikan Gurami, Laju PertumbuhanThe study aims to determine the use of fermentation residue oil palm in artificial feed .Research using a completely randomized design ( CRD ), which consists of 4 treatment three replications.The composition of the treatment is the treatment  A : 12 % of palm oil cake , Treatment B : fermented palm oil cake 15 % , Treatment C : fermented palm oil cake 18 % , Treatment D : fermentation residue palm oil 21 %.This research was conducted for 60 days to determine the specific growth rate of heavy , long daily growth rate , feed conversion , survival and quality of water as a supporter.The results showed the artificial feeding with fermented palm cake to produce a good response to the growth of carp.Feeding artificially by fermentation cake palm oil 18 % ( treatment C ) , gives the best results with a growth rate with the average - average growth rate of the specific weight of 1.502 % daily growth rate long- 4:06 % , the value of feed conversion average - average 3:48 and median survival - average of 90 % .Keywords : Fermentation Palm Kernel Oil, Fish carp, Growth Rate


2014 ◽  
Vol 9 (3) ◽  
pp. 201-213
Author(s):  
Renata Marks-Bielska ◽  
Wiesława Lizińska ◽  
Izabela Serocka

Evaluation of the importance of the USA as the trade partner of Poland is the main objective of the paper, based on the changes in the value of trade during the years 2000-2012 and changes in the structure of trade during the years 2008-2012. The data from the Statistical Yearbooks of Foreign Trade published by the Central Statistical Office was used. The potential for foreign trade growth was illustrated using the simplified analysis based on the gravity model of foreign trade concept. Gradually increasing value of Polish trade with the USA (the average growth rate 9.8%, EU-15 countries 13.1%). Polish exports are characterised by a higher than imports growth rate (USA - exports growth by 12.5%, imports 9.2%, EU-15 - exports 15.1%, imports 11.6%). Trade is strongly dominated by position of one group of products (over 30% share in both exports and imports). The potential of trade is poorly exploited currently. Trade was focused mainly on the countries situated in the close neighbourhood (mainly the EU countries with the domination of Germany).


2021 ◽  
Vol 114 (1) ◽  
Author(s):  
Jérémy Ragusa ◽  
Lina Maria Ospina-Ostios ◽  
Pascal Kindler ◽  
Mario Sartori

AbstractThe Voirons Flysch (Caron in Eclogae Geologicae Helvetiae 69:297–308, 1976), is a flysch sequence aggregated into the sedimentary accretionary prism of the Chablais and Swiss Prealps. Its palaeogeographic location is still debated (South Piemont or Valais realm). We herein present a stratigraphic revision of the westernmost unit of the former Gurnigel Nappe sensu Caron (Eclogae Geologicae Helvetiae 69:297–308, 1976): the Voirons Flysch. This flysch is subdivided into three lithostratigraphic units at the formation level (the Voirons Sandstone, the Vouan Conglomerate, the Boëge Marl), with an additional unit (Bruant Sandstone) of uncertain attribution, ranging from the early Eocene to probably the late Eocene. We further propose a new model of the depositional setting of the deep-sea of the Voirons Flysch based on palaeocurrent directions, the overall geometry and sedimentary features. This model depicts an eastward deflected deep-sea fan. The stratigraphic record of the proximal part of this fan is fairly complete in the Voirons area, whereas its most distal part is only represented by one small exposure of thinly bedded sandstones in the Fenalet quarry. The stratigraphic evolution of the Voirons Flysch shows two major disruptions of the detrital sedimentation at the transition between Voirons Sandstone—Vouan Conglomerate and Vouan Conglomerate—Boëge Marl. The cause of these disturbances has to be constrained in the framework of the palaeogeographic location of the Voirons Flysch.


1999 ◽  
Vol 55 (2) ◽  
pp. 577-580 ◽  
Author(s):  
Abel Moreno ◽  
Manuel Soriano-García

In attempts to obtain protein crystals of a sufficient size for structural studies, lack of knowledge of the physicochemical properties of protein solutions and of their crystal-growth behaviour lead to a bottleneck for drug design as well as for X-ray crystallography. Most formal investigations on crystal-growth phenomena have been focused on equilibrium studies, where the protein is soluble, and on the kinetics of crystal growth, which is related to both nucleation and crystal-growth phenomena. The aim of this work is to measure the crystal-growth rate along a capillary tube used as a growing cell. These experiments were carried out using the gel-acupuncture technique [García-Ruiz et al. (1993). Mater. Res. Bull. 28, 541–546; García-Ruiz & Moreno (1994). Acta Cryst. D50, 484–490; García-Ruiz & Moreno (1997). J. Cryst. Growth, 178, 393–401]. Crystal-growth investigations took place using lysozyme and thaumatin I as standard proteins. The maximum average growth rate obtained in the lower part of the capillary tube was about 35 Å s−1 and the minimum average growing rate in the upper part of the capillary tube was about 8 Å s−1. The crystal-growth rate as a function of the supersaturation was experimentally estimated at a constant height along the capillary tube.


Ocean Science ◽  
2017 ◽  
Vol 13 (5) ◽  
pp. 673-690 ◽  
Author(s):  
Guilherme Franz ◽  
Matthias T. Delpey ◽  
David Brito ◽  
Lígia Pinto ◽  
Paulo Leitão ◽  
...  

Abstract. Coastal defence structures are often constructed to prevent beach erosion. However, poorly designed structures may cause serious erosion problems in the downdrift direction. Morphological models are useful tools to predict such impacts and assess the efficiency of defence structures for different scenarios. Nevertheless, morphological modelling is still a topic under intense research effort. The processes simulated by a morphological model depend on model complexity. For instance, undertow currents are neglected in coastal area models (2DH), which is a limitation for simulating the evolution of beach profiles for long periods. Model limitations are generally overcome by predefining invariant equilibrium profiles that are allowed to shift offshore or onshore. A more flexible approach is described in this paper, which can be generalised to 3-D models. The present work is based on the coupling of the MOHID modelling system and the SWAN wave model. The impacts of different designs of detached breakwaters and groynes were simulated in a schematic beach configuration following a 2DH approach. The results of bathymetry evolution are in agreement with the patterns found in the literature for several existing structures. The model was also tested in a 3-D test case to simulate the formation of sandbars by undertow currents. The findings of this work confirmed the applicability of the MOHID modelling system to study sediment transport and morphological changes in coastal zones under the combined action of waves and currents. The same modelling methodology was applied to a coastal zone (Costa da Caparica) located at the mouth of a mesotidal estuary (Tagus Estuary, Portugal) to evaluate the hydrodynamics and sediment transport both in calm water conditions and during events of highly energetic waves. The MOHID code is available in the GitHub repository.


2021 ◽  
pp. postgradmedj-2021-141244
Author(s):  
Gizem Issin ◽  
Fatih Demir ◽  
Hasan Aktug Simsek ◽  
Diren Vuslat Cagatay ◽  
Mahir Tayfur ◽  
...  

Background and aimsAppendiceal neoplasms are uncommon entities that are usually determined incidentally during the histopathological examination. Different techniques used for the macroscopic sampling of appendectomy material may affect the determinating neoplasms.Materials and methodsH&E-stained slides of 1280 cases who underwent appendectomy between 2013 and 2018 were reviewed retrospectively for histopathological features.ResultsNeoplasms were determined in 28 cases (3.09%); 1 lesion was observed in the proximal part of the appendix, 1 covering the entire length from proximal to distal and 26 in the distal part. In the 26 cases that observed in the distal part, the lesion was seen on both sides of the longitudinal section of the distal appendix in 20 cases, while it was seen on only one distal longitudinal section in the remaining 6 cases.ConclusionThe vast majority of appendiceal neoplasms are seen in the distal part of the appendix, and, in some cases, neoplasms might be seen on only one side of the distal section. Sampling only one-half of the distal part of the appendix, where tumours are most often observed, could result in some neoplasms being missed. Therefore, sampling the whole distal part would be more beneficial to determine small diameter tumours that do not create macroscopic findings.


2012 ◽  
Vol 72 (2) ◽  
pp. 343-351 ◽  
Author(s):  
MC. Bittencourt-Oliveira ◽  
B. Buch ◽  
TC. Hereman ◽  
JDT. Arruda-Neto ◽  
AN. Moura ◽  
...  

Cylindrospermopsis raciborskii (Woloszynska) Seenayya et Subba Raju (Ordem Nostocales) is one of the most troublesome bloom-forming species in Brazil. Understanding the population dynamics of the different morphotypes of C. raciborskii (straight and coiled) could assist in the prediction of favourable conditions for the proliferation of this potentially toxin-producing species. The aim of the present study was to assess the effects of two different light intensities and temperatures on the growth rate and morphology of the trichomes of the straight and coiled morphotypes. For such, two non-toxin producing strains of C. raciborskii were used - one with a coiled trichome (ITEP31) and another with a straight trichome (ITEP28). The strains were cultured in BG-11 medium in a climatic chamber under controlled conditions. Two light intensities (30 and 90 µmol.m-2.s-1 ) were combined at temperatures of 21 and 31 °C and the growth rate and morphological changes were analysed. The morphotypes responded differently to the different temperatures and light intensities. Both strains exhibited faster growth velocities when submitted to higher light intensity and temperature. The lower temperature and higher luminosity hampered the development of both strains. Variations in cellular morphology and an absence of akinetes in both strains were related to the lower temperature (21 °C). The coiled morphotype demonstrated considerable phenotype plasticity, changing the morphology of trichome throughout its growth curve. Although molecular analysis does not sustain the separation of the morphotypes as distinct species, their different eco-physiological responses should be considered further knowledge of extreme importance for the population control of these potentially toxic organisms.


2012 ◽  
Vol 90 (12) ◽  
pp. 1209-1221 ◽  
Author(s):  
A.K. Patidar ◽  
R.K. Pensia ◽  
V. Shrivastava

The problem of radiative instability of homogeneous rotating partially ionized plasma incorporating viscosity, porosity, and electron inertia in the presence of a magnetic field is investigated. A general dispersion relation is obtained using normal mode analysis with the help of relevant linearized perturbation equations of the problem. The modified Jeans criterion of instability is obtained. The conditions of Jeans instabilities are discussed in the different cases of interest. It is found that the simultaneous effect of viscosity, rotation, finite conductivity, and porosity of the medium does not essentially change the Jeans criterion of instability. It is also found that the presence of arbitrary radiative heat-loss function and thermal conductivity modified the conditions of Jeans instability for longitudinal propagation. It is found that, for longitudinal propagation, the conditions of radiative instability are independent of magnetic field, viscosity, rotation, finite electrical resistivity, and electron inertia, but for the transverse mode of propagation it depends upon finite electrical resistivity and strength of magnetic field and is independent of viscosity, electron inertia, and rotation. From the curves we find that viscosity has a stabilizing effect on the growth rate of instability but the thermal conductivity and density-dependent heat-loss function has a destabilizing effect on the instability growth rate.


2020 ◽  
Vol 42 (2) ◽  
pp. 176-186
Author(s):  
Cham Dao Dinh

In recent years, accretion-erosion processes are frequently recorded in the estuary of Cua Dai, Quang Nam province. Most recently, however, sand bars are formed in the estuary not far from the place where the Inland Waterways Authority of Vietnam had previously dredged. The estuary continues to be accreted by sand. These have been drawing special attention of national and international scientists. While there is accretion at the estuary, eroded processes are strongly recorded along the coastlines of Quang Nam province. Therefore, it is necessary to carry out a study in the effects of the hydrodynamic regime on morphological changes in the Cua Dai estuary and coastlines of Quang Nam province. The goal of this paper is to fully interpret the causes, regimes of accretion and erosion processes over the study area. In this study, satellite images and hydrodynamic models of Delft3D and MIKE 11 are applied. The results show a strong accretion process in the estuary of Cua Dai. Sandbar formation across the Cua Dai estuary comes from the interaction of flood, wave, and current conditions during the northeast monsoon. This mainly affects the changes in morphology in the estuary of Cua Dai, Quang Nam.


2021 ◽  
Vol 38 (5) ◽  
pp. 312-318
Author(s):  
Wiliam Carvajal Veitía ◽  
Sofía Alberta León Pérez ◽  
María Elena González Revuelta ◽  
Yanel Deturnel Campo

Objective: To evaluate the morphological changes of Cuban super heavyweight boxers, more and less successful, through the period 1976-2014. Material and method: Thirty super heavy boxers, who were members of the Cuban national teams in the period 1976-2014, were compared; The strategy consisted of separating the group in the periods 1976-1989, 1990-1999, 2000-2009 and 2010-2014. Sixteen anthropometric dimensions were recorded (weight, height, sitting height, six skinfold thickness, five girths and two breadths), from which the body composition and the somatotype were obtained. The data were analyzed applying the Analysis of variance (ANOVA). The conglomerate analysis based on the Euclidean distance was used in order to evaluate the correspondence between physical development and sports performance. A discriminant analysis was carried out in order to analyze the contribution of the anthropometrical variables to the variance of different clusters. Results: Most of the anthropometric dimensions and indicators showed significant differences, having an impact on the increase in adiposity, body fat and endomorphy (p <0.05), as well as the decrease in the indicators dependent on height (p <0.05). The analysis by conglomerates, as well as the study of the Migratory Distances of the somatotype, showed that the Olympic medalist boxers differed in terms of the characteristics of body composition and in terms of the intensity of the somatotype changes in the period 1976-2014. Conclusions: The Cuban boxer of the super heavyweight category showed a wide range of morphological demands, but these were framed within the international trends of professional boxers. The morphological attributes of the Olympic medalists differed from each other, and from the rest of the boxers investigated over time. These results provide anthropometric data of high scientific value, both for selection and for medical control of training.


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