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The criteria of petroleum potential of a sedimentary basin are the features that characterize the evolution of a hydrocarbon system as a geological unit. There are basic and additional criteria of oil and gas potential. Without basic criteria, the functioning of the hydrocarbon system and consequent petroleum field formation is impossible. Additional criteria characterize qualitatively and quantitatively properties of the basic criteria. The properties of all basic criteria are ordered by genesis and summarized in a system that allows to quickly and accurately establish a relationship between them and classify them. The system can be used to select quantitative parameters for geological simulation of different scales, but also for automated applying for petroleum exploration and production. At the same time, the classification of basic criteria can be used at all stages of exploration. At the prospecting stage, when the type of sedimentary basin and the sedimentary conditions are recognized with some uncertainty, it is possible to predict the properties of source rocks, reservoirs, types of traps and seals. If all static basic criteria, such as source rock, reservoir, seal and trap, are available, it is possible to simulate the formation of petroleum fields, including generation, migration, accumulation and subsequent post-accumulation processes. At the stage of exploration and development, the classifications will help to verify the geological and hydrodynamic models of the field, taking into account the link to the regional and local structural plans and correctly identify the geological features of the study object and select the geological analogues.

Both sedimentological factors and secondary processes of lithogenesis influenced the formation of porosity and permeability properties of the reservoir rocks of the Vikulov suite of the Krasnoleninskoe field. The former includes the conditions of sedimentation of the deposits of the Vikulov suite, which at the initial stages of its formation were controlled by the development of a system of incised river valleys, the stages of filling of which, like their composition, have their own characteristics. Also, various genetic types of deposits were formed here. The formation of the upper part of the Vikulov suite took place in a shallow-marine setting, in conditions of storm and wave shallow water, which affected the thin-layered structure of the VK1-3 reservoir. On the other hand, in the sections of a number of wells, dense interlayers are noted, the formation of which is associated with both sedimentation and superimposed processes in lithogenesis, including the formation of hydrocarbon deposits. Therefore, the prediction of the distribution of productive reservoir rocks is the main task when creating a petrophysical model of the field, and to solve this problem, the methods of lithofacies and staged core analysis are used in the work.

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Link for citation: Melnik I.A. Determination of implicit oil-and-gas-bearing sand intervals by statistical-correlation interpretation of GWS data. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 1, рр.54-63. In Rus. The relevance of the considered topic is related to the problem of searching for missed productive low-resistance sand intervals, the existence of which is caused by the presence of surface electrical conductivity in the pores of sandy rock. The purpose of this work is to illustrate briefly the results of using the technology of statistical-correlation interpretation of geophysical well logging in the search for implicitly missed low resistivity oil and gas reservoirs. Method. This paper briefly shows the method of statistical-correlation interpretation of well logging materials. Theoretical physico-chemical and formal-logical justifications of the method of statistical-correlation interpretation are presented. This method is based on the principles of correlation of measured and calculated geophysical and petrophysical parameters of the studied sand interval, which changes along the well are caused by dominant geochemical processes of superimposed epigenesis in a certain local interval in the territory of deep fluid penetration. The product of the approximation coefficient and the statistical interval parameter of two samples of measured characteristics corresponds to the statistical intensity of sand interval transformation processes. On the basis of a standard set of geophysical well logging data, using the method of statistical-correlation interpretation of well logs in sandy formations it is possible to determine the intensity of secondary processes such as pyritization, kaoliniteization, pelitization, carbonatization and formation of a double electric layer in clays, some of which may be the cause of an implicit decrease in the electrical resistivity of the rock. Certain boundary values of the intensities of these secondary processes may serve as an indicator of the presence of hydrocarbons in the studied formations. Results. The validity of the statistical-correlation method of well logging data interpretation was confirmed when comparing the results of calculating the intensities of transformation processes with the results of petrographic core analysis. By determining the intensities of mineral transformation processes affecting the increase in surface electrical conductivity of sandy rocks in the Nizhneluginetskaya well, promising Jurassic reservoirs were identified, which were confirmed by the results of core alcohol-benzene extraction. In the Vakh field, the results of identifying promising Cretaceous reservoirs on the basis of the use of technology of statistical-correlation interpretation of logging data were confirmed by the results of formation tests. In the previously missed sand interval oil was obtained. And, secondary carbonatization was an indicator of the presence of hydrocarbons with a probability of 80 %. Conclusions. If we use well logging data (both old and new fund) to calculate the intensity of geochemical processes as an indicator of the presence of hydrocarbons and the boundary values of these intensities in the sandy formations, it is possible with ~80 % probability to reveal the implicitly missed low-resistance oil and gas reservoirs.

The origin, migration pathways, as well as the influence of secondary processes of oil and natural gas accumulated in lower Cretaceous to lower Miocene strata of the western part of the Polish Outer Carpathians (between Kraków and Pilzno towns) based on results of organic geochemical analyses are investigated in this paper. Oil and thermogenic hydrocarbon gases were generated mainly from type II kerogen, and type II and III kerogen mixed in various proportions. These kerogens mainly occur in the Oligocene Menilite beds of the Silesian and Dukla nappes. Oils were generated from early to late "oil window". Secondary cracking was recorded in oils from Dukla nappe, other secondary processes including biodegradation, water washing and evaporative fractionation were also developed to a various extent in many oils. The most biodegraded oils occur in seep S-Li, and the most extensive water washing is observed in the oil from seep S-Sa/1. The evaporative fractionation processes most significantly occur in the selected deepest parts of the multi-horizontal Biecz field. Hydrocarbon gases originated during both microbial and thermogenic processes of organic matter transformation. Natural gas has not been subjected to biodegradation processes. Carbon dioxide is derived from both microbial and thermogenic decomposition processes of organic matter and was generated together with hydrocarbon gases. [ABSTRACT FROM AUTHOR]

This paper focuses on the post-accretion history of CV3 chondrites, through a combination of petrographic and mineralogical characterization, magnetic measurements, spectral (Raman and Infrared) and thermo-gravimetric analysis of 31 meteorites (including 7 falls, 21 Antarctic and 3 non-Antarctic finds) spanning a wide metamorphic range. We classify the 21 Antarctic chondrites and the Bukhara fall into the CV Red , CV OxA , and CV OxB subgroups. We establish quantitative parameters relevant for this sub-classification. In comparison to CV Ox , CV Red chondrites are characterized by (i) a lower abundance of matrix, (ii) a higher abundance of metal, (iii) the presence of Ni-poor sulfides. In comparison to CV OxB , CV OxA are characterized by (i) similar matrix abundance, (ii) a higher abundance of metal, (iii) the presence of metal almost exclusively under the form of awaruite, (iv) lower Ni content of sulfides, (v) lower magnetic susceptibility and saturation remanence. Both CV Ox (CV OxA and CV OxB) and CV Red experienced aqueous alteration, and contain oxyhydroxides and phyllosilicates. We show that the abundance of these hydrated secondary minerals observed today in individual CV chondrites decreases with their peak metamorphic temperature. This is interpreted either as partial dehydration of these secondary minerals or limited hydration due to the rapid exhaustion of the water reservoir during parent body thermal metamorphism. Moreover, the lower abundance of oxyhydroxides (that have a lower thermal stability than phyllosilicates and may in large part postdate the peak of thermal metamorphism) in more metamorphosed CV chondrites is interpreted as lower availability of aqueous fluids during retrograde metamorphism in these meteorites. Lastly, we show that in comparison to CV OxB , CV OxA are systematically (i) more metamorphosed, (ii) less hydrated, (iii) depleted in ferromagnetic minerals, (iv) but enriched in metal in the form of secondary awaruite. CV OxA may be thermally metamorphosed CV OxB. CV Red are significantly different from CV Ox (matrix abundances, alteration products, opaque minerals), but span the same wide metamorphic range. This could be indicative of a laterally heterogeneous CV parent body, or suggest the existence of distinct parent bodies for CV Ox and CV Red chondrites. [ABSTRACT FROM AUTHOR]

A geochemical study of crude oil and natural gas from producing wells and seeps within the Lower Cretaceous–Oligocene sandstone reservoirs of the most eastern part of the Polish Outer Carpathians was conducted for the evaluation of their origin, migration pathways and the effects of secondary processes (biodegradation, water washing and evaporative fractionation). The petroleum was generated from mixed marine/terrigenous organic matter (type-II/III kerogen) occurring mostly in Oligocene Menilite beds in the Silesian and Skole nappes. Shales within Upper Cretaceous–Palaeocene Istebna and Lower Cretaceous Veřovice, Lgota and Spas beds are considered as an additional source of hydrocarbons (mainly gaseous). Biodegradation processes were recorded in numerous oils, especially occurring in seeps, but the extent of these processes is not severe, because steranes and terpanes were not affected. All oils are more-or-less water washed, while the evaporative fractionation processes are developed only on a minimal scale. The natural gases are primarily of thermogenic origin, usually co-genetic with oil and often contain components of secondary microbial degradation of both oil and natural gas (13C-enriched CO2 and 13C-depleted CH4). Gases with the highest microbial methane contribution have been recorded in petroleum accumulated in Dwernik and Łodyna fields. [ABSTRACT FROM AUTHOR]

Computer model that makes it possible to study the interaction of ion beam with biological objects has been created. Contribution of secondary particles to the formation of the total radiation dose was investigated. The model contains all the necessary elements of formation of ion beam and we can interactively change the parameters of the model. For processing of simulation results additional program codes were created. Studies were carried out on the object which size and physicochemical properties are similar to biological cell in the human body.

We present results of research into the tectonic, lithofacies, and geochemical formation conditions of the Erema-Chona oil ans gas accumulation. We characterize present-day structures and their formation history, consider the composition, structure, formation conditions, postdepositional alterations, and porosity-permeability properties of the Osa, Ust'-Kut, Preobrazhenka, Erbogachen, and Upper Chona Horizons, assess the quality of the overlying seals, and describe the technique and results of quantitative estimation of the petroleum potential of pay beds. Modern technologies for the development of oil reserves are also presented, along with geological and economic assessment of hydrocarbon resources of the study object. [ABSTRACT FROM AUTHOR]

The transition between the Middle Atlas and the Sais Basin contains a sequence of alluvial fans from the Plio-Quaternary period. These fans are mostly made up of debrites and are found resting unconformably on top of carbonate beds from the Jurassic Period. This location provides a key case study for investigating the primary processes of aggradation, as well as the secondary processes that alter alluvial fan deposits. Alluvial fans are developed through primary processes that occur intermittently over time, resulting in both active and inactive sectors. Internal and external organization of the deposits is, however, partially influenced by secondary processes that can cause mechanical, chemical, and/or biochemical changes, making the comprehension of alluvial fan development processes more complex. In this study, we investigated fan development processes by examining five lithostratigraphic logs and seven sedimentary facies in eight alluvial fans that have merged together. The findings indicate that debris flows were the main driver of fan development, with some contribution from sheet floods and mud-flows. In addition, the study suggests that secondary processes, including mechanical, chemical, biochemical, and diagenetic processes, have had a substantial impact on sediment deposition. The mechanical processes include brittle deformation, incision, reworking, and desiccation. On the other hand, the chemical and/or biochemical processes are evidenced by paleosol and calcrete development, as well as cementation, micritization, dissolution, development of porosity, oxidation, recrystallization, epigenesis, and neoformation. These processes would have been influenced by hydrological, hydrogeological and karstic factors, which are closely linked to the generally semi-arid climatic conditions punctuated by wet phases. • Alluvial fan deposits in the Middle Atlas-Sais Basin transition zone are mainly debris flow-derived. • Diagenetic versus primary processes' impact on alluvial fans in a karstic context. • Secondary mechanical and chemical/biochemical processes prevail in the inactive sectors of alluvial fans. • Biological activity controls the formation of calcretes and diagenetic processes (cementation, micritization, dissolution). • Climate, tectonics, karstification, and hydrogeology (autocyclic and allocyclic factors) govern secondary processes. [ABSTRACT FROM AUTHOR]

Abstract Chondrites are exhumed from their parent bodies by impacts, which at the same time can result in heating and mechanical modification (compaction, deformation, fracturing, etc.). However, whether impacts are responsible for the occurrence of heated C2s remains controversial since radiogenic and solar heating have also been invoked to explain them. Here we report a Raman and infrared study of the composition and structure of Insoluble Organic Matter (IOM) in a series of 39 CM and C2-ungrouped chondrites. These parameters are tracers of the extent and nature of thermal metamorphism a meteorite has experienced and reflect the degree to which the thermally driven and irreversible carbonization of IOM has proceeded. We propose a carbon-based classification of heated C2 chondrites that reveals a high occurrence frequency of thermally processed C2 chondrites (>36%). This classification is in agreement with the mineralogical classification scheme of Nakamura (2005). Strongly heated C2 chondrites (PCA 02012, PCA 91008, Y 96720) display an IOM structural evolution that is dissimilar to that of type 3 chondrites that experienced long duration radiogenic thermal metamorphism. These differences almost certainly reflect kinetic constraints on IOM modification during short duration heating events. QUE 93005 is a weakly heated chondrite that experienced a retrograde aqueous alteration. Its very aliphatic-rich IOM points to a parent body hydrogenation through interactions with water. The closed-system conditions required by this mechanism could be satisfied by a kinetic confinement during a very short duration impact. MET 01072, a heavily compacted and uni-axially deformed chondrite, did not experience post-accretional heating. In this case, the deformation features probably reflect a low-velocity impact. In contrast, the weakly metamorphosed chondrite EET 96029 experienced one or several low pressure impacts that triggered mild heating and partial dehydration without deformation features. The study of a series of lithologies from the Tagish Lake C2-ungrouped chondrite confirms the coexistence of various degrees of post-accretional alteration, the most altered lithologies having experienced a moderate degree of heating. Overall, the high prevalence of heating in C2 chondrites, the evidence of short-duration heating in the most heated C2s and the ability of low velocity collisions to trigger heating favor impacts (against solar heating), as the dominant heating mechanism. Finally, our set of data does not support the action of a low temperature oxidation process that would control the aliphatic abundance in unheated primitive C2s. [ABSTRACT FROM AUTHOR]

The presence of hydrated minerals in chondrites indicates that water played an important role in the geologic evolution of the early Solar System; however, the process of aqueous alteration is still poorly understood. Renazzo-like carbonaceous (CR) chondrites are particularly well-suited for the study of aqueous alteration. Samples range from being nearly anhydrous to fully altered, essentially representing snapshots of the alteration process through time. We studied oxygen isotopes in secondary-minerals from six CR chondrites of varying hydration states to determine how aqueous fluid conditions (including composition and temperature) evolved on the parent body. Secondary minerals analyzed included calcite, dolomite, and magnetite. The O-isotope composition of calcites ranged from δ 18 O ≈ 9 to 35‰, dolomites from δ 18 O ≈ 23 to 27‰, and magnetites from δ 18 O ≈ −18 to 5‰. Calcite in less-altered samples showed more evidence of fluid evolution compared to heavily altered samples, likely reflecting lower water/rock ratios. Most magnetite plotted on a single trend, with the exception of grains from the extensively hydrated chondrite MIL 090292. The MIL 090292 magnetite diverges from this trend, possibly indicating an anomalous origin for the meteorite. If magnetite and calcite formed in equilibrium, then the relative 18 O fractionation between them can be used to extract the temperature of co-precipitation. Isotopic fractionation in Al Rais carbonate-magnetite assemblages revealed low precipitation temperatures (∼60 °C). Assuming that the CR parent body experienced closed-system alteration, a similar exercise for parallel calcite and magnetite O-isotope arrays yields “global” alteration temperatures of ∼55 to 88 °C. These secondary mineral arrays indicate that the O-isotopic composition of the altering fluid evolved upon progressive alteration, beginning near the Al Rais water composition of Δ 17 O ∼ 1‰ and δ 18 O ∼ 10‰, and becoming increasingly 16 O-enriched toward a final fluid composition of Δ 17 O ∼ −1.2‰ and δ 18 O ∼ −15‰. [ABSTRACT FROM AUTHOR]

The Caldes de Boí geothermal waters show important differences in pH (6.5–9.6) and temperature (15.9ºC–52ºC) despite they have a common origin and a very simple circuit at depth (4km below the recharge area level). Thes differences are the result of secondary processes such as conductive cooling, mixing with colder shallower waters, and input of external CO2, which affect each spring to a different extent in the terminal part of the thermal circuit. In this paper, the secondary processes that control the geochemical evolution of this system have been addressed using a geochemical dataset spanning over 20 years and combining different approaches: classical geochemical calculations and geochemical modelling. Mixing between a cold and a thermal end-member, cooling and CO2 exchange are the processes affecting the spring waters with different intensity over time. These differences in the intensity of the secondary processes could be controlled by the effect of climate and indirectly by the geomorphological and hydrogeological setting of the different springs. Infiltration recharging the shallow aquifer is dominant during the rainy seasons and the extent of the mixing process is greater, at least in some springs.Moreover, significant rainfall can produce a decrease in the ground temperature favouring the conductive cooling. Finally, the geomorphological settings of the springs determine the thickness and the hydraulic properties of the saturated layer below them and, therefore, they affect the extent of the mixing process between the deep thermal waters and the shallower cold waters. The understanding of the compositional changes in the thermal waters and the main factors that could affect them is a key issue to plan the future management of the geothermal resources of the Caldes de Boí system. Here, we propose to use a simple methodology to assess the effect of those factors, which could affect the quality of the thermal waters for balneotherapy at long-term scale. Furthermore, the methodology used in this study can be applied to other geothermal systems.

High-resolution X-ray diffraction (HRXRD), X-ray reflectometry (XRR), X-ray photoelectron spectroscopy (XPS), and Atomic-force microscopy (AFM) were used to study the influence of the chemical activity of implanted ions (N+, O+, F+ or Ne+) on the structure of the damaged Si layer in SIMOX substrates. The implantation conditions were chosen so that the number of primary defects and the projected range were approximately the same for the implanted ions. HRXRD showed that the depth distribution of the residual damage depends on the chemical activity of the impurity. This may result from the quasi-chemical interaction between the radiation-induced point defects (VSi and Sii) and the impurity atoms. The shape of the density profiles and the thickness of the transition surface layer obtained from the XRR data are different for the implanted ions. The [100] faceted surface features of the samples prepared by SIMOX technology are preserved after implantation with the ions. AFM revealed a reduction of the lateral correlation length. The magnitude of this effect depends on the chemical activity of the implanted ions. Silicon oxidation at a depth of 10-15 nm is shown by XPS to change depending on the implanted ion. [ABSTRACT FROM AUTHOR]

The Caldes de Boí geothermal waters show important differences in pH (6.5-9.6) and temperature (15.9°C-52°C) despite they have a common origin and a very simple circuit at depth (4km below the recharge area level). These differences are the result of secondary processes such as conductive cooling, mixing with colder shallower waters, and input of external CO2, which affect each spring to a different extent in the terminal part of the thermal circuit. In this paper, the secondary processes that control the geochemical evolution of this system have been addressed using a geochemical dataset spanning over 20 years and combining different approaches: classical geochemical calculations and geochemical modelling. Mixing between a cold and a thermal end-member, cooling and CO2 exchange are the processes affecting the spring waters with different intensity over time. These differences in the intensity of the secondary processes could be controlled by the effect of climate and indirectly by the geomorphological and hydrogeological setting of the different springs. Infiltration recharging the shallow aquifer is dominant during the rainy seasons and the extent of the mixing process is greater, at least in some springs. Moreover, significant rainfall can produce a decrease in the ground temperature favouring the conductive cooling. Finally, the geomorphological settings of the springs determine the thickness and the hydraulic properties of the saturated layer below them and, therefore, they affect the extent of the mixing process between the deep thermal waters and the shallower cold waters. The understanding of the compositional changes in the thermal waters and the main factors that could affect them is a key issue to plan the future management of the geothermal resources of the Caldes de Boí system. Here, we propose to use a simple methodology to assess the effect of those factors, which could affect the quality of the thermal waters for balneotherapy at long-term scale. Furthermore, the methodology used in this study can be applied to other geothermal systems. [ABSTRACT FROM AUTHOR]

We present 53 Mn– 53 Cr ages of secondary carbonates in Renazzo-like (CR) chondrites, determined by secondary ion mass spectrometry. The timing of aqueous alteration in CR chondrites has been unconstrained in the literature. We measured 53 Mn– 53 Cr isotope systematics in carbonates from three different CR-chondrite lithologies. Calcite in the interchondrule matrix of Renazzo, calcite in the matrix of GRO 95577, and dolomite in a dark inclusion of Renazzo all show excesses in 53 Cr, interpreted as the daughter product from the decay of 53 Mn. The Renazzo calcite yields an initial ratio of ( 53 Mn/ 55 Mn) 0 = (3.6 ± 2.7) × 10 −6 , and the Renazzo dark inclusion dolomite ranges from ( 53 Mn/ 55 Mn) 0 = (3.1 ± 1.4) × 10 −6 (corrected to the RSF of a calcite standard) to (3.7 ± 1.7) × 10 −6 (corrected to an inferred dolomite RSF). When anchored to the D’Orbigny angrite, the Renazzo carbonates yield ages between 4563.6 and 4562.6 Ma, or ∼4.3–5.3 Myr after the formation of CV CAIs. Calcite measured in the heavily altered specimen GRO 95577 yields a shallower slope of ( 53 Mn/ 55 Mn) 0 = (7.9 ± 2.8) × 10 −7 , corresponding to a much younger age of 4555.4 Ma, or ∼12.6 Myr after CAI formation. The two Renazzo ages are contemporaneous with Mn–Cr ages of carbonates in Tagish Lake, CI, and CM chondrites, but the GRO 95577 age is uniquely young. These findings suggest that early aqueous alteration on chondritic parent bodies was a common occurrence, likely driven by internal heating from 26 Al decay after accretion. The young carbonate ages of GRO 95577 suggest that either the CR parent body was sufficiently large to sustain heating from 26 Al for ∼8 Myr, or that late-stage impact events supplied heat to the region where GRO 95577 originated. [ABSTRACT FROM AUTHOR]

Computer model that makes it possible to study the interaction of ion beam with biological objects has been created. Contribution of secondary particles to the formation of the total radiation dose was investigated. The model contains all the necessary elements of formation of ion beam and we can interactively change the parameters of the model. For processing of simulation results additional program codes were created. Studies were carried out on the object which size and physicochemical properties are similar to biological cell in the human body. [ABSTRACT FROM AUTHOR]

Aerosols hygroscopicity is generally differentiating for particles among various sources, leading to complex effects on visibility impairment and cloud formation. However, the hygroscopicity of aerosol particles from diverse sources is not yet fully understood. Here, combining field observations at an urban site in Beijing and a positive matrix factorization model, we identified aerosols hygroscopicity of six different sources, nucleation, traffic, cooking, aging primary, residential heating, and regional secondary, which corresponds to hygroscopic growth factors (Gfs) of 1.23, 1.15, 1.17, 1.44, 1.48, and 1.47, respectively at relative humidity of 90%. On polluted days, Gf values of particles for the accumulation-mode particles were higher than that under clean conditions. This is largely due to the hygroscopic sources represented by aged and secondary processes showed the dominant role in aerosol population. While on clean days, the Gfs of 40-nm particles showed larger values, that is closely associated with the photochemical-nucleation-sourced particles. By further applying the Gfs together with aerosol spectrum to predict cloud nuclei concentration (CCN), we find the predicted and observed CCN number concentration are well correlated at typical supersaturation in cloud. The study further reveals the dominant roles of secondary processes, contributing up to 90% of the total cloud nuclei. Primary particles from traffic/cooking activities contributed only ∼5%, although they account for 30–40% of the total particle number concentrations in urban Beijing during the studied period. The results indicate the source apportionment of Gfs can well interpret the variation in hygroscopicity of aerosols under different atmospheric conditions and evaluate their effects on cloud formation. • The hygroscopicity of aerosol particles from specific sources was identified in winter of Beijing. • The hygroscopic growth factors together with aerosol spectrum could predict N CCN well at typical supersaturation in cloud. • Secondary sources were the dominant contributor to the total cloud nuclei, while primary particles contributed less. [ABSTRACT FROM AUTHOR]

Well known for its anti-oxidative and anti-inflammation properties, curcumin is a polyphenol found in the rhizome of Curcuma longa. In this study, we evaluated the effects of curcumin on behavioral recovery, glial scar formation, tissue preservation, axonal sprouting, and inflammation after spinal cord injury (SCI) in maleWistar rats. The rats were randomized into two groups following a balloon compression injury at the level of T9–T10 of the spinal cord, namely vehicle- or curcumin-treated. Curcumin was applied locally on the surface of the injured spinal cord immediately following injury and then given intraperitoneally daily; the control rats were treated with vehicle in the same manner. Curcumin treatment improved behavioral recovery within the first week following SCI as evidenced by improved Basso, Beattie, and Bresnahan (BBB) test and plantar scores, representing locomotor and sensory performance, respectively. Furthermore, curcumin treatment decreased glial scar formation by decreasing the levels of MIP1α, IL-2, and RANTES production and by decreasing NF-κB activity. These results, therefore, demonstrate that curcumin has a profound anti-inflammatory therapeutic potential in the treatment of spinal cord injury, especially when given immediately after the injury. [ABSTRACT FROM AUTHOR]

Abstract: Arid alluvial fan aggradation is highly episodic and fans often comprise active and inactive sectors. Hence the morphology and texture of fan surfaces are partly determined by secondary processes of weathering and erosion in addition to primary processes of aggradation. This introduces considerable uncertainty in the identification of formative processes of terrestrial and Martian fans from aerial and satellite imagery. The objectives of this study are (i) to develop a model to describe the sedimentological and morphological evolution of inactive fan surfaces in arid settings, and (ii) to assess the relative importance of primary processes of aggradation and secondary processes of weathering and reworking for surface morphology and sedimentology and for the stratigraphic record. We studied an alluvial fan characterized by a recently active sector and a long-abandoned, inactive sector along the coast of the hyperarid Atacama Desert. Here, rates of primary geomorphic activity are exceptionally low because of extreme aridity, while weathering rates are relatively high because of the effects of coastal fogs. Long-term processes of fan aggradation and reworking were determined through sedimentological facies analysis of stratigraphic sections. Ground surveys for textural and morphological patterns at the fan surface were integrated with remote-sensing by an Unmanned Airborne Vehicle (UAV). Discharges and sediment-transport capacities were calculated to estimate the efficiency of secondary runoff in reshaping the inactive fan sector. Stratigraphic sections reveal that the fan was dominantly aggraded by debris flows, whereas surface morphology is dominated by debris-flow signatures in the active sector and by weathering and runoff on the inactive sector. On the latter, rapid particle breakdown prevents the formation of a coarse desert pavement. Furthermore, relatively frequent local runoff events erode proximal debris-flow channels on the inactive sector to form local lag deposits and accumulate fine sediment in low-gradient distal channels, forming a well-developed drainage pattern that would suggest a runoff origin from aerial images. Nevertheless, reworking is very superficial and barely preserved in the stratigraphic record. This implies that fans on Earth and Mars that formed dominantly by sporadic mass flows may be masked by a surface morphology related to other processes. [Copyright &y& Elsevier]

Axotomized neurons have the innate ability to undergo regenerative sprouting but this is often impeded by the inhibitory central nervous system environment. To gain mechanistic insights into the key molecular determinates that specifically underlie neuronal regeneration at a transcriptomic level, we have undertaken a DNA microarray study on mature cortical neuronal clusters maintained in vitro at 8, 15, 24 and 48 hrs following complete axonal severance. A total of 305 genes, each with a minimum fold change of ±1.5 for at least one out of the four time points and which achieved statistical significance (one-way ANOVA, P < 0.05), were identified by DAVID and classified into 14 different functional clusters according to Gene Ontology. From our data, we conclude that post-injury regenerative sprouting is an intricate process that requires two distinct pathways. Firstly, it involves restructuring of the neurite cytoskeleton, determined by compound actin and microtubule dynamics, protein trafficking and concomitant modulation of both guidance cues and neurotrophic factors. Secondly, it elicits a cell survival response whereby genes are regulated to protect against oxidative stress, inflammation and cellular ion imbalance. Our data reveal that neurons have the capability to fight insults by elevating biological antioxidants, regulating secondary messengers, suppressing apoptotic genes, controlling ion-associated processes and by expressing cell cycle proteins that, in the context of neuronal injury, could potentially have functions outside their normal role in cell division. Overall, vigilant control of cell survival responses against pernicious secondary processes is vital to avoid cell death and ensure successful neurite regeneration. [ABSTRACT FROM AUTHOR]

The behavior of a family of mean-field glass models is reviewed. The models are analysed by means of a Langevin-based approach to the dynamics and a replica theory computation of the thermodynamics. We focus on the phase diagram of a particular model case, where glass-to-glass transitions occur between phases with a different number of characteristic time-scales for the relaxation processes. The appearance of Johari-Goldstein processes as collective reorganizations of sets of fast processes is discussed. [ABSTRACT FROM AUTHOR]

Size-resolved aerosol organic carbon (OC) and water-soluble OC (WSOC) was determined weekly in urban Beijing between 2013 and 2018. The results showed that in winter, the concentrations of WSOC and OC in fine (<2.1 μm) and coarse (>2.1 μm) mode were highest in 2013. During the following years, the concentrations of WSOC and OC were lower but an increasing trend was found from 2014 to 2016, which might be due to the increasing precursor concentrations. From summer 2013 to 2018, the concentrations of OC and WSOC in both fine and coarse mode decreased, which might be affected by decreasing emission intensity and photochemical oxidation. To characterize the seasonality of WSOC, two intensive field observations were further performed in winter 2013 and summer 2018. In winter of 2013, WSOC was mainly enriched in PM 1 (<1 μm) on clean days and lightly polluted days. In addition, the fine mode maximum shifted from 0.43-0.65 μm to 1.1–2.1 μm with the haze development due to the hygroscopic growth of particles. In summer of 2018, the WSOC was mainly concentrated in PM 1 , but in a few samples, the maximum size appeared in coarse mode. This difference might due to the different relative humidity and air mass sources. While the formation process of WSOC in winter was affected by photochemical oxidation below 2.1 μm, in 1.1–2.1 μm, it tended to change from photochemical oxidation to aqueous-phase oxidation. For the coarse mode WSOC formation in winter, however, it was mainly affected by heterogeneous processes. The findings advanced our understanding of the annual trends, size distribution and formation processes of WSOC, with significant implications for air pollution control in Beijing and surrounding regions. Image 1 • Carbonaceous species in both fine and coarse modes decreased from 2013 to 2018. • The size distribution of WSOC shifted from fine to coarse during haze episodes. • In summer, coarse mode WSOC was mainly condensed on sea salt. • In winter, WSOC formation was affected by secondary processes. [ABSTRACT FROM AUTHOR]

The origin, migration pathways, and the influence of secondary processes of oil and natural gas accumulated in Lower Cretaceous to Lower Miocene strata of the central part of the Polish Outer Carpathians are investigated based on organic geochemical analyses. Oil and thermogenic hydrocarbon gases were mainly generated from both types II and III kerogens in the Oligocene Menilite beds of the Silesian, Skole and Dukla nappes. Moreover, some gases originated from Type III kerogen of Lower Cretaceous Veřovice shales in the Silesian Nappe and Lower Cretaceous Spas shales in the Skole Nappe. These gases migrated and subsequently mixed with oil and gas produced from Type II kerogen in the Menilite beds. The most extensive biodegradation and water washing were observed in oils from Harklowa and Iwonicz fields, and in oil from the BF (Franek) dug-well in Bóbrka-Rogi field (one of the world's oldest with exploitation started in 1854) of the Silesian Nappe. Oils most affected by evaporative fractionation come from Krościenko and Iwonicz Zdrój fields. Natural gas originated mainly from low-mature thermogenic processes ("oil window") with some primary microbial gas contribution (primary carbon dioxide reduction), and many gas samples show secondary alteration caused by biodegradation. Carbon dioxide originated from both thermogenic kerogen decarboxylation and microbial processes. • Oil and gas origin and migration in the Polish Outer Carpathians. • Secondary processes of oil (biodegradation and water washing). • Secondary processes of gas (secondary microbial methane and biodegraded gas). • Oil from both types II and III kerogens were produced. • Thermogenic and microbial origin of gaseous hydrocarbons and carbon dioxide. [ABSTRACT FROM AUTHOR]

Images of streamer propagation and branching are presented in a short-point plane gap in air at atmospheric pressure. The results are obtained by employing a finite-element flux corrected transport (FE-FCT) algorithm in conjunction with a subgridding scheme for the efficient and accurate calculation of secondary effects during streamer development and propagation. The significant reduction in time required for the calculations makes numerical modeling a useful tool for a better understanding of physical processes, such as branching, that are central to the propagation and development of streamers. [ABSTRACT FROM AUTHOR]

Well known for its anti-oxidative and anti-inflammation properties, curcumin is a polyphenol found in the rhizome of Curcuma longa. In this study, we evaluated the effects of curcumin on behavioral recovery, glial scar formation, tissue preservation, axonal sprouting, and inflammation after spinal cord injury (SCI) in male Wistar rats. The rats were randomized into two groups following a balloon compression injury at the level of T9-T10 of the spinal cord, namely vehicle- or curcumin-treated. Curcumin was applied locally on the surface of the injured spinal cord immediately following injury and then given intraperitoneally daily; the control rats were treated with vehicle in the same manner. Curcumin treatment improved behavioral recovery within the first week following SCI as evidenced by improved Basso, Beattie, and Bresnahan (BBB) test and plantar scores, representing locomotor and sensory performance, respectively. Furthermore, curcumin treatment decreased glial scar formation by decreasing the levels of MIP1α, IL-2, and RANTES production and by decreasing NF-κB activity. These results, therefore, demonstrate that curcumin has a profound anti-inflammatory therapeutic potential in the treatment of spinal cord injury, especially when given immediately after the injury.