Lumpy Structure Research Articles

Characterization of extracted alpha cellulose from Manihot esculenta (cassava) peels as formulation aid for paracetamol tablet

Background: Alpha-cellulose as a pharmaceutical excipient can be employed as a binding agent in tablet formulation. Cassava peels husk are waste agricultural material and is being investigated for its α-cellulose for use in oral solid pharmaceutical formulation. Purpose: The objective of this study is to extract α-cellulose from cassava peels agro-industrial waste using a standard method, subject the extracted cassava peels cellulose and determine its phytochemical and physicochemical properties of formulated granules of paracetamol. Methods: Alpha-cellulose from cassava peel was extracted using alkali method. The fresh peels were prepared, milled into slurry and de-watered to obtain a coarse wet material, dried, milled and sieved to obtain very fine powdered particles. Phytochemical analysis and characterization of extracted α-cellulose powder were determined. Differential scanning calorimetry (DSC), scanning electron micrographs (SEM), and x-ray diffractogram (XRD) analysis of extracted cassava peel cellulose were done. Paracetamol granules was prepared by wet granulation using varying concentrations of the binders. Results: DSC and XRD results revealed a semi-crystalline material with amorphous and crystalline regions. while the SEM showed a lumpy structure and reticular shape. Pre-compression evaluations of the formulated batches of paracetamol granules showed that cassava peels cellulose (CPC) have similar flow properties with those of microcrystalline cellulose BP (MCC) and acacia BP (ACA) powders respectively. The granules have free flow properties with average angles of repose (CPC ≤ 27.60 MCC < 26.90 and ACA ≤ 25.60), compressibility index (CPC ≤ 25, MCC ≤ 23 and ACA ≤ 21.7%), Hausner’s ratio (CPC ≤ 1.32, MCC ≤ 1.31, and ACA ≤ 1.27) respectively. Conclusion: The extracted cassava peel α-cellulose was found ideal as pharmaceutical excipient binder in oral solid dosage forms.

PROPERTIES OF URBAN SOILS AFTER DECONTAMINATION MEASURES ON THE RADIOACTIVELY CONTAMINATED TERRITORY OF THE CITY OF ELEKTROSTAL

We studied morphological properties, pH, organic carbon content, and specific activity of 137Cs and natural radionuclides (40K, 226Ra, 232Th) in the upper horizons of soils in deactivated and slightly damaged areas of the city. The studies were carried out in the urban ecosystems of the city of Elektrostal (Moscow region) in 2019, i.e. 6 years after local precipitation of 137Cs due to a radiation incident. Morphological features of the upper horizons of urban soils were: brownish-gray color, light-loamy composition, small-lumpy and lumpy structure, inclusions of construction and household waste. In the upper horizons of urbiquasizems and urban soils, a low carbon content (less than 1%) with high coefficients of variation - were detected. In the studied urban soils, a wide range of water pH values was noted: from acidic (4,6-5,5) to highly alkaline (> 8,0) reaction. Correlation analysis showed that in the upper horizons of UR, the content of organic carbon was reduced and alkalinization of the soil environment was observed. The accumulative type of distribution of 137Cs was recorded for soil profiles of polluted urban ecosystems in which decontamination measures were not carried out. The profiles of urban soils that were subjected to decontamination revealed low values of the specific activity of 137Cs in surface bulk layers and maxima in buried contaminated horizons. In the bulk horizons of UR, which include a large amount of crushed stone, there is an increase in the specific activity of 226Ra. Some technogenic horizons UR and TCH, consisting mainly of quartz sand, are characterized by very low values of specific activities 226Ra and 40K. Correlations of chemical and radiation indicators in the profiles of urban soils reflect the different composition and properties of upper horizons formed as a result of excavation and decontamination work.

ВЛИЯНИЕ КУЛЬТУР ТРАВОПОЛЬНОГО СЕВООБОРОТА НА ПЛОДОРОДИЕ ПОЧВЫ

The development of effective, highly productive crop rotations in modern agricultural production is an urgent task. The purpose of the research is to study the influence of grass–field crop rotation crops on agrophysical, biological indicators of soil fertility and crop yields. The research was carried out at the experimental site of the Department of Adaptive Landscape Agriculture of the National Research Institute of Agriculture of the VNC RAS in 2021-2022. The soil of the experimental site is represented by leached chernozems on pebbles. The experiments, phenological observations, and statistical processing of the obtained data were carried out according to generally accepted methods. Under various crops, the lumpy structure (at the beginning of the growing season) accounted for from 13.46 to 49.56%, the macrostructure – from 48.53 to 81.88%, aggregates less than 0.25 mm – from 1.88 to 8.01%. By the end of the growing season, the proportion of the dusty fraction under winter wheat decreased from 8.01% to 1.09%. The structural coefficient varied between 2.48 (corn) and 2.79 (oats + clover). The highest indicators of total porosity at the beginning of the growing season were noted under crops: oats + clover (57.5%), clover (57.6%) and potatoes (58.8%), and at the end of the growing season under clover (57.1%) and potatoes (59.6%). The highest yield of feed units was noted for the following variants: oats + clover – 9.83 t/ha, clover – 9.49 t/ha, corn – 9.49 t/ha. More digestible protein was contained in the clover crop, the rest of the crops were at about the same level. The best indicators of energy value were obtained for corn for grain – 101.0 GJ/ha, for perennial grasses of 1 and 2 years of use – 57.3-65.0 GJ/ha, winter wheat – 81.4 GJ/ha and potatoes – 69.9 GJ/ha.

Characterization of Alluvial Soil for Growth of Chinese Betel (Peperomia pellucida L.)

This study aims to determine the characterization of alluvial soil as a place to grow Chinese betel (peperomia pellucida L.) in Ambon city. Parameters studied included morphological characterization of alluvial soil and description of Chinese betel nut (Peperomia pellucid a L.). The results of observations in the field and analysis of soil samples in the laboratory that have been collected are used as material to identify soil morphological characterization. Meanwhile Chinese betel nut (Peperomia pellucid a L.) collected from alluvial soil was selectively explored by exploring the research area using the Cruise Method. Furthermore, a phytochemical test was carried out to determine its phytochemical content. The results showed that the color of the soil and the rusty color of the alluvial soil in Ambon City was generally brown. The alluvial soil structure at the study site has an O horizon with a soil layer thickness of 17 cm, an A horizon with a thickness of 45 cm soil lumpy structure and a Bw horizon with a soil thickness of 30 cm and the C horizon with a thickness of 65 cm is classified as having a globular lumpy soil structure, It has a high clay and silt content. The lower the soil solum, the lower the C-organic content. The soil in Ambon city has moderate fertility. Low base saturation is associated with low C-organic content in the soil. Chinese sirih that grows on alluvial soil types in Ambon City contains several classes of compounds that are beneficial to health like flavonoids, alkaloids, tripenoids, phenolics, tannins and saponins so that they have ethnomedicin effects such as anticancer, antimicrobial, antidiabetic, antihypertensive and antioxidant activities.

Pressure Sensor Based on a Lumpily Pyramidal Vertical Graphene Film with a Broad Sensing Range and High Sensitivity.

Wearable sensors are vital for the development of electronic skins to improve health monitoring, robotic tactile sensing, and artificial intelligence. Active materials and the construction of microstructures in the sensitive layer are the dominating approaches to improve the performance of pressure sensors. However, it is still a challenge to simultaneously achieve a sensor with a high sensitivity and a wide detection range. In this work, using three-dimensional (3D) vertical graphene (VG) as an active material, in combination with micropyramid arrays and lumpy holders, the stress concentration effects are generated in nano-, micro-, and macroscales. Therefore, the lumpily pyramidal VG film-based pressure sensor (LPV sensor) achieves an ultrahigh sensitivity (131.36 kPa-1) and a wide response range (0.1-100 kPa). Finite element analysis demonstrates that the stress concentration effects are enhanced by the micropyramid arrays and lumpy structures in micro- and macroscales, respectively. Finally, the LPV pressure sensors are tested in practical applications, including wearable health monitoring and force feedback of robotic tactile sensing.

Tomography of stellar halos: what does anisotropy in a stellar halo tell us?

The stellar halo of the Milky Way is known to have a highly lumpy structure due to the presence of tidal debris and streams accreted from the satellite galaxies. The abundance and distribution of these substructures can provide a wealth of information on the assembly history of the Milky Way. We use some information-theoretic measures to study the anisotropy in a set of Milky Way-sized stellar halos from the Bullock & Johnston suite of simulations that uses a hybrid approach coupling semi-analytic and N-body techniques. Our analysis shows that the whole-sky anisotropy in each stellar halo increases with the distance from its centre and eventually plateaus out beyond a certain radius. All the stellar halos have a very smooth structure within a radius of ∼ 50 kpc and a highly anisotropic structure in the outskirts. At a given radius, the anisotropies at a fixed polar or azimuthal angle have two distinct components: (i) an approximately isotropic component and (ii) a component with large density fluctuations on small spatial scales. We remove the contributions of the substructures and any non-spherical shape of the halo by randomizing the polar and azimuthal coordinates of the stellar particles while keeping their radial distances fixed. We observe that the fluctuating part of the anisotropy is completely eliminated, and the approximately uniform component of the anisotropy is significantly reduced after the sphericalization. A comparison between the original halos and their sphericalized versions reveals that the approximately uniform part of the anisotropy originates from the discreteness noise and the non-spherical shape of the halo whereas the substructures contribute to the fluctuating part. We show that such distinction between the anisotropies has the potential to constrain the shape of the stellar halo and its substructures.

Differences between tumor clones of B lymphocytes with restriction of kappa or lambda immunoglobulin light chains in patients with chronic lymphocytic leukemia.

e19520 Background: The purpose of this study was to compare morphological and immunophenotypic characteristics of the tumor population of B-lymphocytes with varying restrictions of immunoglobulin light chains in patients with chronic lymphocytic leukemia (CLL). Methods: We examined 30 patients with CLL (median age 64.9±8.6 years). All patients underwent CBC+DIFF blood tests (Sysmex XE 2100, Japan), morphological examinations (BioVision; Micros, Austria), and immunophenotyping (IPT) by multicolor flow cytometry (Navios 10/3, Beckman Coulter, USA) of the bone marrow and venous blood. According to the IPT results, the patients were divided into: group 1 - 22 patients (73.3%) with tumor cells expressing kappa immunoglobulin light chains, and group 2 - 8 patients (26.7%) with lambda immunoglobulin light chains. Statistical processing of results was performed in the STATISTICA 13.0 program. Results: Morphological tests revealed differences between tumor populations of B lymphocytes. In group 1, the tumor population was represented by small cells of the same type with scanty, often unvisible cytoplasm and nuclei with a lumpy chromatin structure, without distinct nucleoli. In group 2, the sizes of cells varied from small to large, with abundant cytoplasm, round or folded nuclei, smoothed chromatin structure and 1-2 nucleoli. Prolymphocytes were observed among tumor cells (8.1±1.7% of WBC). IPT also revealed differences in tumor clones: morphological uniformity of tumor cells in group 1 was observed in the distribution of tumor cells reflected in low parameters of light scattering on the diagram: location to the left along the FSC axis - from 200 to 400 units and below along the SSC axis - from 10 to 160 units. In group 2, the lymphoid zone was heterogeneous and stretched on the plot: location to the right along the FSC axis - from 200 to 1000 units and higher along the SSC axis - from 10 to 400 units, closer to the monocyte zone, which indicated morphological polymorphism of tumor cells. The expression of CD45 also differed: in group 1, the expression was higher and tumor B lymphocytes were higher by fluorescence intensity on a dot plot on the CD45 / SSC scale in the second half of the third decade and in the fourth decade - to the right compared with group 2, where aberrant B lymphocytes were in the third decade and more to the left. The CD45 expression allowed defining differentiation of the tumor clone: the population in group 1 was represented by mature cells, and in group 2 by less mature and/or intermediate forms. There were no significant differences in the expression of other markers. The revealed differences were typical of both the peripheral blood and bone marrow. Conclusions: The study established morphological and immunophenotypic differences between tumor clones of B lymphocytes expressing either kappa or lambda immunoglobulin light chains in patients with CLL.

Reflection and thermal characteristics of a novel reflective phase-change coating irradiated by high-power continuous laser

In order to improve the smart control performance of laser protective materials under the high-power laser irradiation, a novel smart phase-change laser protective coating is proposed and prepared by using phenolic resin and zirconia, combined with the slow-gradient heating and drying technique and spraying process. The influences of laser ablation on the macrostructure of coating shows that the prepared coating can withstand the laser irradiation up to 3102 W/cm2 for 7 s at the wavelength of 1064 nm. The effect of high-intensity laser irradiation on structure evolution has been further investigated. It is found that increasing the laser power density will change the coating microscopic structure from the initial lumpy structure to a flocculent crystal structure, and finally form a flake structure, which is considered as the main reason for the increase of reflectivity. The experimental results show that the reflectivity on the coating surface can be increased by 75.7% before and after laser irradiation. Finally, the phase transition temperature of the coating is investigated, and the thermal insulation performances between coating and substrate have also been compared. The temperature insulation performance of the novel phase-change coating is found to be 1.2–15 times higher than that of the substrate.

Morphological features of the soil cover of slope lands in the south of the Volga uplands within the urban landscapes of Volgograd

The paper deals with morphological properties of agrogenically transformed chestnut soils of slope lands in the south of the Volga upland within the urban landscape of Volgograd. It is established that as a result of agrogenesis, erosion, land use change, as well as of agroforestry reclamation measures performed, both anthropogenic deeply transformed and postagrogenic soils have been formed. The greatest changes under the influence of agrogenesis are noted in morphological structure of profiles. Agrogenesis results in degradation of soils involved in active agricultural use due to intensified sheet and rill erosion. In eroded soils there is noticed a decrease in the thickness of agrohumic layer, formation of furrow bottom compaction and changes in structure. Their characteristic feature is the presence on the surface of a homogeneous agro-abraded horizon with lumpy structure, in the lower part of which secondary carbonates inherited from the carbonate horizon and resulted from deep plowing may occur. Soils slightly exposed and not exposed to erosion processes have an agrohumus horizon on the surface, which depending on soil tillage can have thickness from 19 to 36 cm. At present, the annual agricultural practices at the plot include mowing of weeds and disk plowing to 20 cm depth. Earlier moldboard plowing to 40 cm depth was performed. All agrogenically-modified soils are characterized by HCl reaction with carbonates from the surface. Carbonate accumulations in agrogenic soils, as a rule, have a segregated form that indicates rapid summer drying of the profile and short period of soil solutions migration. Upper boundary of accumulative-carbonate horizons of agrogenic soils on the average is at 42 cm depth. Such occurrence of carbonate horizons in general is typical both of natural non-eroded soils of dry-steppe zone and of soils involved in agricultural land use. Under forest plantations the original chestnut soils were transformed into turbated agrozems due to deep ameliorative cultivation preceded planting of woody and shrub vegetation. Soil preparation practices applied before tree species planting resulted in transformation of original chestnut soils into turbated agrozems, which is due to deep (up to 60 cm) soil reclamation. The forest belt, being a “barrier” between the field parts, contributed to the formation of a stratified small horizon (trait) of 10 cm thickness for more than 70 years due to the constant inflow of fine-grained soil and decay of leaf and herbaceous debris.

The Spiderweb Structure of Stratocumulus Clouds

Stratocumulus clouds have a distinctive structure composed of a combination of lumpy cellular structures and thin elongated regions, resembling canyons or slits. The elongated slits are referred to as “spiderweb” structure to emphasize their interconnected nature. Using very high resolution large-eddy simulations (LES), it is shown that the spiderweb structure is generated by cloud-top evaporative cooling. Analysis of liquid water path (LWP) and cloud liquid water content shows that cloud-top evaporative cooling generates relatively shallow slits near the cloud top. Most of liquid water mass is concentrated near the cloud top, thus cloud-top slits of clear air have a large impact on the entire-column LWP. When evaporative cooling is suppressed in the LES, LWP exhibits cellular lumpy structure without the elongated low-LWP regions. Even though the spiderweb signature on the LWP distribution is negligible, the cloud-top evaporative cooling process significantly affects integral boundary layer quantities, such as the vertically integrated turbulent kinetic energy, mean liquid water path, and entrainment rate. In a pair of simulations driven only by cloud-top radiative cooling, evaporative cooling nearly doubles the entrainment rate.

The optimisation of the cylinder-spiral soil-cultivating roller

Designed cylinder-tillage spiral skating rink with spiral work items, which form a fine lumpy structure of the sowing layer of soil with grain size corresponding to agrotechnical requirements, while helping the soil surface, mulching the top layer of soil over the seeds, seal the depth of their placement, providing the required contact of seeds with soil is necessary to ensure the uniformity of germination. At the theoretical level, it is determined that an increase in the pinching angle leads to an increase in the size of the hollow smooth pipe of the roller. This occurs while increasing the depth of deformation of the layer of crushed soil and the radius of the clump of soil. However, a change in the radius of a hollow smooth roller of more than 0.3 m does not lead to a slight increase in the pinching angle. Therefore, increasing the radius of the hollow smooth roller over 0.3 m is not rational, as it will increase the metal content of the structure. After analyzing the obtained mathematical models of the soil treatment process with a roller, we optimized the parameters of a cylindrical-spiral roller: speed of 11 km/h, mass of ballasting loads of 100 kg, step of the spiral turn of 40 mm, and the departure of the spiral screw of 35 mm. These modes ensure the formation of a qualitatively compacted soil layer in the zone of planting seeds of agricultural crops, which is confirmed by the maximum value of the processing quality criterion for matching the density of the soil after rolling with a cylindrical-spiral roller CCS = 0.98 (while the density of the sown layer addition 1185...1215 kg/m3), which fully satisfies the agrotechnical optimum. The yield of barley of the Nutans-553 variety became higher after the use of an innovative cylindrical-spiral roller by 6.4 % and 9.3 %, respectively, of the yield after the impact of serial ККSh rollers and ring rollers of the seeding machine. In the course of evaluating the metal consumption of structures of the innovative cylindrical-spiral roller and the ring-spur roller, a difference of 70% per unit width of the grip was revealed.

Innovative Deflector Soil-Cultivating Paw

When planting, most planters coulters enter the ground from the top. They meet hard clods of soil, jump, changing the depth of planting seeds. Some seeds are thrown to the surface. As a result, the sowing germination, as well as yield, decreases. ( Research purpose ) To develop an innovative soil-cultivating pointed paw, eliminating the rejection of soil and the formation of unevenness of the surface, as well as increasing the productivity of the cultivator. ( Materials and methods ) The authors determined the setting parameters of the developed deflector pointed paw with the involvement of mathematical device and taking into account the requirements for the working bodies of soil-cultivating units. ( Results and discussion ) The authors developed an innovative deflector pointed paw. A triangular deflector was placed over the ploughshare. They determined the optimal angle of deflector inclination in the horizontal plane-15-25 degrees, and the height of the installation of the pointed paw over the blade- in 1.5 times above the depth of soil cultivation. It was found that the rear part of the deflector, which has a serrated shape and curved down, allows to grind the soil, forming a small-lumpy structure. It was shown that the soil, moving along the deflector, in collision with the curved part returns to the surface, closing and leveling the formed furrow. The triangular shape of the rack between the ploughshare and the deflector significantly reduces the clogging of coulters with plant residues. ( Conclusions ) The authors proved that the leveled soil surface with a finely lumpy structure of the top layer can be obtained using a deflector pointed paw, which eliminates the use of rollers. This reduces the material consumption of the cultivator, fuel consumption, and productivity increases by 50 percent as a result of increasing the speed of soil cultivation to 18 kilometers per hour.

Composites from by-products of the food industry for the development of superabsorbent biomaterials

The aim of this study deals is the development of superabsorbent green composite materials based on food industry by-products that could be revalorised. Plasma porcine protein (PPP) and soy protein isolate (SPI) are surpluses of the food industry that content a high amount of hydrophilic amino acid residues. Thus, different PPP/SPI blends (0/100, 25/75, 50/50, 75/25 and 100/0) were processed and characterized conveniently. The thermal response of these blends is between a thermosetting (PPP) and a thermoplastic (SPI) behaviour, where a minimum in the elastic moduli around the gelation temperature of PPP (∼65°C) was found. It is an important fact that all composites produced revealed a superabsorbent character (>1000%), being higher as the PPP/SPI ratio increases, as PPP imparts a greater deformability to the biocomposite. The duration of the dehydrothermal (DHT) treatment at 50°C to which samples were submitted prior to their immersion has proven to be highly influential, reinforcing the structure but losing the superabsorbent character after 72h. The microstructure of composites is a combination of the porous structure of PPP and the lumpy structure of SPI, suggesting a difference in the water absorption mechanism for both proteins. These composites might be considered to develop an environmentally friendly product to replace extensively used acrylic derivatives.

In vivo reflectance confocal microscopy for evaluating common facial hyperpigmentation.

In clinical settings, atypical facial hyperpigmentation such as nevus of Ota, acquired bilateral nevus of Ota-like macules (ABNOM), melasma, and café-au-lait spots are often missed and misdiagnosed. Summarizing in vivo reflectance confocal microscopy (RCM) features of the hyperpigmentation is helpful in the diagnosis of ambiguous lesions. We recruited 196 patients referred for unequivocal facial hyperpigmentation, including 55 patients with nevus of Ota, 45 patients with ABNOM, 62 patients with melasma, and 34 patients with café-au-lait spots. The RCM images were evaluated at the epidermis, the dermis-epidermis junction (DEJ), and the upper papillary dermis from both hyperpigmented patches and normal skin. In the superficial and middle dermis, 41 of 55 patients (74.5%) with nevus of Ota were characterized by a cord-like or lumpy structure between the collagen fibers. And there was no melanin deposition detected in the dermis in 14 of 55 (25.5%) patients. In ABNOM, 37 of 45 (82.2%) patients were characterized by a cord-like or lumpy structure in the superficial dermis and 8 of 45 patients (17.8%) was no melanin deposition detected in the dermis. The epidermis was no difference between nevus of Ota, ABNOM, and the normal skin. Melasma was detected increased cobblestone pattern in the epidermis of all patients, branching architecture in 21 of 62 patients (33.9%), and focally aggregated round to triangular cells in the upper dermis of 18 of 62 patients (29.0%). In all patients with afé-au-lait spots, increased cobblestone pattern in the epidermis and regular and increased density of ringed pattern in the DEJ were visualized. Our findings indicate that RCM may be useful in the auxiliary diagnosis of nevus of Ota, ABNOM, melasma, and café-au-lait spots.

Decolorizing Methyl Orange by Fe-Electrocoagulation Process – A Mechanistic Insight

The aim of this work is to study the removal of methyl orange (MO) using electrocoagulation (EC) process. An electrochemical cell consisting of two iron electrodes, with 22.5 cm² as an active surface, is used. Operating conditions are optimized such as nature and concentration of the supporting electrolyte, current density, pH, inter-electrode distance, MO concentration, and the connection mode. The decolorization degree obtained after 15 min of EC reached 83% at pH 7.25 with a current density of 64 A/m². Depending on pH, three EC process mechanisms are suggested and less or more significant removal performances are obtained in these tests. The Scanning Electron Microscopy (SEM) observations show that the flocs formed by the EC process have two distinct morphologies: a lumpy structure and an amorphous structure, formed by particles of various sizes. The Energy Disperses X-ray (EDX) analysis of the surface of the flocs formed by the EC process shows a spectrum with levels of major elements of iron, oxygen and chloride, as well as carbon, sodium and aluminum are detected as minor elements. As proved in terms of MO elimination through this research and due to its several advantageous, EC process would find its convenient place in wastewater treatment technology.

MEADOW-STEPPER CHERNOZEMS (TYPICAL) OF LVOV REGION: GEOGRAPHY AND REGIONAL PECULIARITIES OF THE PROFILE CONSTRUCTION

Purpose. The available cartographic and printed materials show us the presence of meadow-steppe Chernozems (Typical) in the structure of the soil cover in Lviv region as typical zonal components. This fact cannot be considered to be completely true. The main aim of research is to reveal the true nature of the spatial mosaic of Typical Chernozems, their place in the landscape structure of the region.Data & Methods. The basis of the researches are large-scale soil maps (scale 1:10 000 and 1: 5 000) of collective farms of the Lviv region, advanced schemes of geomorphological and physic-geographical zonation of Ukraine, and materials of field and laboratory researches of the Lviv region chernozems. At the base comparative-geographical method within of the Lviv region (Pidpodilskyi natural area, Sokal-Torchynska and Syansko-Dnisterska hills, Pasmove Pobuzhya and Opillya) were selected representative of key areas. Within each of them, in the way deep trenching and soil-environmental profiles, using historical-evolutionary and genetic-morphological methods, have researched formation of the soil cover structure and modern geochemical contiguity of chernozems with other soils. In order to identify quantitative parameters of regional differences of chernozems are used complex laboratory standard methods.Results. The spatial mosaic of Typical Chernozems of Lviv region has a definite regional lithological and hydrological restriction. They are the main component of soil cover found only on the left bank-side of the Western Bug river and on the Nearpodolian natural area and to a lesser extent on the Range Pobuzhzha. These soils have been formed on well aerated loess plains. Typical Chernozems are not zonal soils in Lviv region. They hold local or island positions among zonal and a little podzolized soils. These Chernozems genetically belong to a group of leached and mycelial-calcareous Chernozems.Typical Cernozems of the Sokal plateau are mostly shallow and medium profound (53-66 cm). They have a lumpy structure and the bedding line of calcium carbonate is closer to the surface (40-45 cm) with rapid boiling. There are mole drains within the transitional humus horizon. Also, there is relatively high occurrence (70-80 cm) of segregational carbonate neoformations with the humic transition horizon of clearly tongue or pocket form in the soil profile. Morever, these soils do not have a clear-accumulative carbonate horizon. Chernozems of the Range Pobuzhya are mainly medium profound, gleyey, leached without the accumulative carbonate horizon. Chernozems of the Nearpodolian region are profound and medium profound, mycelial-calcareous, not gleyey or profound-gleyey. Also, they have a strong grain structure, mainly carbonate. Chernozems typical for terrace complexes are profound or over profound, leached and have well grained structure that makes them similar to meadow-chernozemic soils, yet they are not gleying.

Pleistocene Pingo in the Central Part of the East European Plain

AbstractSeveral rimmed depressions of different size, filled with lakes or bogs, occur within the glaciofluvial lowlands of the Moscow region, in the central part of the East European Plain. One such depression, at Krasnoye lake, has a diameter of 300 m and a maximal depth of 9 m. The rim is 2– 5 m high. The sedimentary deposits of the rim, observed in several pits, consist mostly of sand with inclusions of loamy sand, loam and clay. They have a lumpy structure with weak and irregular layering and are underlain by fluvial sand of the third terrace of the Moscow River with clear horizontal bedding. The rim deposits are interpreted to be of a slope type and probably formed due to slumping and washout from the slopes of a large pingo which existed here in the cold epoch of the Upper Pleistocene. The rims surrounding some other depressions in the Moscow region, however, have quite different structures, which suggests that their genesis may be different. Copyright © 2015 John Wiley & Sons, Ltd.

Transitions in Structure of Clay Fills due to Suction Oscillations

In North-western Bohemia the excavated overburden from open-cast coal mines is end-dumped in fills. Clay-type soil prevails among the filled soils. As a consequence of the character and state of the soil, together with the mining and dumping technology, the clay fill comprises a typical lumpy structure. Large and open macrovoids between the single lumps are a characteristic feature of the clay fills. The filled overburden forms spoil heaps under high angles of repose (as high as 40°) which is governed by size and shape of the lumps. However these slopes cannot be considered for design of clay fill final slopes. The lumpy clay fill structure is metastable. Structure transitions influencing the mechanical behaviour and thus slope inclination of the heaps are presented in this contribution. Three main agents are responsible for the transitions of the lumpy structure: Plastic straining of relatively weak lumps as a consequence of overburden load; collapse on wetting of the open metastable structure mainly in theearly stages after landfilling; and oscillations of matric suction. Long-term monitoring of matric suction in years 2004 - 2008 atdepths up to 2 metres in the low-gradient slope of the reclaimed clay fill in the Bílina mine show clear seasonal suction oscillations.

Does the potentially toxic cyanobacterium Microcystis exist in the soda lakes of East Africa?

Presently, the food chains of the famous saline alkaline flamingo-lakes of East Africa are the focus of intense scientific discussion as the lakes host toxic cyanobacteria, which when consumed by Lesser Flamingos, weaken the birds and therefore make them susceptible to attacks by infective diseases. The distribution, genetic and toxicological aspects of Microcystis in Kenya has been studied extensively. Although there are reports on the occurrence of Microcystis in Kenya’s hypersaline alkaline lakes, they have not been confirmed. Our investigations carried out over a 10-year period in about 50 inland waters showed that Microcystis occurs exclusively in freshwaters, but never in the hypersaline alkaline lakes. Microscopic examinations of the phytoplankton of these lakes revealed the presence of Anabaenopsis abijatae (Nostococales) whose lumpy structure makes it roughly similar to Microcystis when viewed under an inverted microscope. We conclude that the possible occurrence of Microcystis in hypersaline alkaline lakes is doubtful and, as such, confirmatory studies including microphotographic documentation of findings should be carried out.

Numerical modelling of lumpy clay landfill

AbstractTwo trial motorway embankments built on a landfill consisting of clayey lumps were monitored over the period of 3 and 5 years, respectively. The subsoil of the embankment was instrumented by hydrostatic levelling profiles, pore pressure transducers and depth reference points installed in boreholes. An advanced constitutive model for clays (hypoplastic model for clays with meta‐stable structure) was used for numerical modelling of both case histories. Basic hypoplastic model for clays was calibrated using isotropic compression tests and triaxial compression tests on reconstituted clay. Three additional model parameters describing the effects of lumpy structure were calibrated using oedometer tests on specimens prepared from scaled‐down lumpy material (material with smaller size of clay lumps). The performance of the model was evaluated by comparison with the results of the centrifuge model of self‐weight consolidated landfill. Finally, the hypoplastic model was used for simulation of both trial embankments and the results were compared with in situ measurements. The degradation of the lumpy structure of the upper layer of the in situ landfill due to weathering was back analysed using monitoring data. Copyright © 2010 John Wiley & Sons, Ltd.