Institute of Geology, Komi Science Centre

The Northern Circumpolar Soil Carbon Database was developed in order to determine carbon pools in soils of the northern circumpolar permafrost region. The area of all soils in the northern permafrost region is approximately 18,782 × 10 3 km 2 , or approximately 16% of the global soil area. In the northern permafrost region, organic soils (peatlands) and cryoturbated permafrost‐affected mineral soils have the highest mean soil organic carbon contents (32.2–69.6 kg m −2 ). Here we report a new estimate of the carbon pools in soils of the northern permafrost region, including deeper layers and pools not accounted for in previous analyses. Carbon pools were estimated to be 191.29 Pg for the 0–30 cm depth, 495.80 Pg for the 0–100 cm depth, and 1024.00 Pg for the 0–300 cm depth. Our estimate for the first meter of soil alone is about double that reported for this region in previous analyses. Carbon pools in layers deeper than 300 cm were estimated to be 407 Pg in yedoma deposits and 241 Pg in deltaic deposits. In total, the northern permafrost region contains approximately 1672 Pg of organic carbon, of which approximately 1466 Pg, or 88%, occurs in perennially frozen soils and deposits. This 1672 Pg of organic carbon would account for approximately 50% of the estimated global belowground organic carbon pool.

This is the first of two papers that review approximately 200 publications on mercury (Hg) in coal; topics reviewed in this paper include: (a) analytical and historical introduction; (b) some peculiarities of Hg environmental geochemistry; (c) estimation of the Hg coal Clarke value; (d) occurrence of high-Hg coals; (e) mode of Hg occurrence in coal; (f) factors influencing the distribution of Hg in coal; and (g) origins of Hg in coal. Aspects of the environmental impact of Hg due to coal combustion and coking are noted throughout the review, and are more fully examined in second and final paper of this review. The Clarke value for Hg in coal (world-wide average Hg content) is 0.10 (±0.01) ppm Hg, regardless of coal rank. However, if the Hg content is expressed on an ash basis, bituminous rank coals average 0.87 (±0.08 ppm) Hg, and lower rank coals average 0.62 (±0.06) ppm. In general, Hg is a very “coalphile” element; that is, it has a strong affinity for organic and inorganic coal matter, but is obligatory authigenic. There are some coals that are enriched in Hg by 1 to 2 orders of magnitude above the Clarke value. Such coals are located in the Donbas (Ukraine), Appalachian basin and Texas (USA), Russian Far East, and Southern China. Mercury in these coals is usually accompanied by other chalcophile trace elements. In low-sulfur coals, which are generally poor in Hg, only two Hg sites dominate: Hgorg and Hgsulfide (commonly pyritic mercury, Hgpyr). High-sulfur coals usually contain higher amounts of Hg, which is typically in the Hgpyr form. In the unique Hg-enriched Donbas coals, both HgS and metallic mercury (Hg°) also occur. Because of the extremely strong affinity of Hg2+ for humic matter, it is theoretically possible for syngenetic (or early epigenetic) Hg to accumulate in peats and lignites. Indeed, the amount of Hg in some tropic and moderate zone peats is greater than or equal to the Hg content of typical coal. Until the recent discovery of syngenetic volcanic Hg accumulations in Canadian coals, such Hg accumulations in coal were unknown. The most important type of Hg enrichment in coals is an epigenetic, low-temperature hydrothermal process; the Nikitovka (Ukraine), Warrior (USA), and Guizhou (China) basins are good examples. In the two latter coal basins, the paragenetic association Hg–As–Au–Tl is similar to Carlin-type Au deposits. The most notably Hg-rich basin is the Donbas–Donetsk coal basin situated in the Ukraine and Russia. Numerous coalfields in the Donbas are enriched in Hg by one order of magnitude above the coal Clarke level. The Hg in the Donbas was due to hydrothermal mineralization passing through sheared zones. The extraction and use of Hg-bearing Donbas coals have created very difficult environmental problems for the Ukrainian people.

Abstract Near the Barents Sea coast in northern Timan, turbidites of probable Neoproterozoic age are intruded by pre-tectonic dolerites and a major suite of gabbros, granites and syenites (some nepheline bearing). Zircon ion microprobe dating of three plutons has yielded well-defined ages of 613–617 Ma. This alkaline igneous activity apparently represents a final phase of Vendian extensional magmatism prior to Timanian Orogeny. Previous work on late to post-orogenic calc-alkaline granites in the basement beneath the Pechora Basin, three hundred kilometres towards the SE, has yielded c. 550–560 Ma single zircon Pb-evaporation ages. These compositionally different intrusive suites are inferred to constrain the main phase of Timanian Orogeny to c. 610–560 Ma.

Aging is a major worldwide medical challenge. Not surprisingly, identifying drugs and compounds that extend lifespan in model organisms is a growing research area. Here, we present DrugAge (http://genomics.senescence.info/drugs/), a curated database of lifespan-extending drugs and compounds. At the time of writing, DrugAge contains 1316 entries featuring 418 different compounds from studies across 27 model organisms, including worms, flies, yeast and mice. Data were manually curated from 324 publications. Using drug-gene interaction data, we also performed a functional enrichment analysis of targets of lifespan-extending drugs. Enriched terms include various functional categories related to glutathione and antioxidant activity, ion transport and metabolic processes. In addition, we found a modest but significant overlap between targets of lifespan-extending drugs and known aging-related genes, suggesting that some but not most aging-related pathways have been targeted pharmacologically in longevity studies. DrugAge is freely available online for the scientific community and will be an important resource for biogerontologists.

Abstract A procedure for structural investigations by X-ray diffraction of mixed-layer structures incorporating swelling layers has been developed. For each sample, specimens saturated with different cations (Na, Mg, and Ca), are analyzed both as air-dried and as glycolated. One structural model fitting all the observed patterns then provides the structure of the sample. Samples tested include: Mite-smectite (I-S) minerals from Kazachstan (a rectorite), Dolna Ves in Slovakia, Kinnekulle in Sweden, the North Sea, and Scania in Sweden. The fitting of the patterns of the Kazachstan rectorite demonstrated that the instrumental parameters applied in the modeling were correct. For the I-S minerals from Slovakia and Kinnekulle the observed patterns were fitted with one two-component I-S model. However, the Ca-saturated and air-dried specimen of the Kinnekulle bentonites had two types of swelling interlayers. For the Slovakian I-S with Reichweite = 2, an alternative two-phase I-S plus I–V (V = vermiculite) model fitted the experimental X-ray diffraction patterns equally well. The I-S mineral from Scania is in fact a three-component I-T-S (T = tobelite) and the North Sea sample is a four-component I-S-V-V, one type of the swelling layers having swelling characteristics intermediately between smectite and vermiculite. In addition to layer types and distribution, interlayer compositions, such as the amount of interlayer glycol and water and of fixed and exchangeable cations, were determined.

This review concerns pectin substances, the most complex class of plant polysaccharides. For the most part, the data reported after 1998 are presented; the references to earlier works are made only in the historical aspect. New data on the structure of pectin substances, their physiological activity, their role in plants, and their valuable physical properties are surveyed.

Pectins are the major component of plant cell walls, and they display diverse biological activities including immunomodulation. The pectin macromolecule contains fragments of linear and branched regions of polysaccharides such as homogalacturonan, rhamnogalacturonan-I, xylogalacturonan, and apiogalacturonan. These structural features determine the effect of pectins on the immune system. The backbones of pectic macromolecules have immunosuppressive activity. Pectins containing greater than 80% galacturonic acid residues were found to decrease macrophage activity and inhibit the delayed-type hypersensitivity reaction. Branched galacturonan fragments result in a biphasic immunomodulatory action. The branched region of pectins mediates both increased phagocytosis and antibody production. The fine structure of the galactan, arabinan, and apiogalacturonan side chains determines the stimulating interaction between pectin and immune cells. This review summarizes data regarding the relationship between the structure and immunomodulatory activity of pectins isolated from the plants of the European north of Russia and elucidates the concept of polypotency of pectins in native plant cell walls to both stimulate and suppress the immune response. The possible mechanisms of the immunostimulatory and anti-inflammatory effects of pectins are also discussed.

Soil life supports the functioning and biodiversity of terrestrial ecosystems. Springtails (Collembola) are among the most abundant soil arthropods regulating soil fertility and flow of energy through above- and belowground food webs. However, the global distribution of springtail diversity and density, and how these relate to energy fluxes remains unknown. Here, using a global dataset representing 2470 sites, we estimate the total soil springtail biomass at 27.5 megatons carbon, which is threefold higher than wild terrestrial vertebrates, and record peak densities up to 2 million individuals per square meter in the tundra. Despite a 20-fold biomass difference between the tundra and the tropics, springtail energy use (community metabolism) remains similar across the latitudinal gradient, owing to the changes in temperature with latitude. Neither springtail density nor community metabolism is predicted by local species richness, which is high in the tropics, but comparably high in some temperate forests and even tundra. Changes in springtail activity may emerge from latitudinal gradients in temperature, predation and resource limitation in soil communities. Contrasting relationships of biomass, diversity and activity of springtail communities with temperature suggest that climate warming will alter fundamental soil biodiversity metrics in different directions, potentially restructuring terrestrial food webs and affecting soil functioning.

[1] This study describes detailed partitioning of phytomass carbon (C) and soil organic carbon (SOC) for four study areas in discontinuous permafrost terrain, Northeast European Russia. The mean aboveground phytomass C storage is 0.7 kg C m−2. Estimated landscape SOC storage in the four areas varies between 34.5 and 47.0 kg C m−2 with LCC (land cover classification) upscaling and 32.5–49.0 kg C m−2 with soil map upscaling. A nested upscaling approach using a Landsat thematic mapper land cover classification for the surrounding region provides estimates within 5 ± 5% of the local high-resolution estimates. Permafrost peat plateaus hold the majority of total and frozen SOC, especially in the more southern study areas. Burying of SOC through cryoturbation of O- or A-horizons contributes between 1% and 16% (mean 5%) of total landscape SOC. The effect of active layer deepening and thermokarst expansion on SOC remobilization is modeled for one of the four areas. The active layer thickness dynamics from 1980 to 2099 is modeled using a transient spatially distributed permafrost model and lateral expansion of peat plateau thermokarst lakes is simulated using geographic information system analyses. Active layer deepening is expected to increase the proportion of SOC affected by seasonal thawing from 29% to 58%. A lateral expansion of 30 m would increase the amount of SOC stored in thermokarst lakes/fens from 2% to 22% of all SOC. By the end of this century, active layer deepening will likely affect more SOC than thermokarst expansion, but the SOC stores vulnerable to thermokarst are less decomposed.

The Zr-Hf geochemical indicator, i.e., the Zr/Hf ratio (in wt %) in granitic rocks is proposed to be used as the most reliable indicator of the fractionation and ore potential of rare-metal granites. It was empirically determined that the fractional crystallization of granitic magma according to the scheme granodiorite → biotite granite → leucogranite → Li-F granite is associated with a decrease in the Zr/Hf ratio of the granites. The reason for this is the stronger affinity of Hf than Zr to granitic melt. This was confirmed by experiments on Zr and Hf distribution between granitic melt and crystals of Hf-bearing zircon (T = 800°C, P= 1 kbar). The application of the Zr/Hf indicator was tested at three classic territories of rare-metal granites: eastern Transbaikalia, central Kazakhstan, and the Erzgebirge in the Czech Republic and Germany. The reference Kukul’bei complex of rare-metal granites in eastern Transbaikalia (J3) is characterized by a uniquely high degree of fractionation of the parental granitic melt, with the granites and their vein derivatives forming three intrusive phases. The biotite granites of phase 1 are barren, the leucogranites of phase 2 are accompanied by greisen Sn-W mineral deposits (Spokoininskoe and others), and the final dome-shaped stocks of amazonite Li-F granites of phase 3 host (in their upper parts) Ta deposits of the “apogranite” type: Orlovka, Etyka, and Achikan. The Kukul’bei Complex includes also dikes of ongonites, elvanes, amazonite granites, and miarolitic pegmatites. All granitic rocks of the complex are roughly coeval and have an age of 142±0.6 Ma. The Zr/Hf ratio of the rocks systematically decreases from intrusive phase 1 (40–25) to phases 2 (20–30) and 3 (10–2). Compared to other granite series, the granites of the Kukul’bei Complex are enriched in Rb, Li, Cs, Be, Sn, W, Mo, Ta, Nb, Bi, and F but are depleted in Mg, Ca, Fe, Ti, P, Sr, Ba, V, Co, Ni, Cr, Zr, REE, and Y. From earlier to later intrusive phases, the rocks become progressively more strongly enriched or depleted in these elements, and their Zr/Hf ratio systematically decreases from 40 to 2. This ratio serves as a reliable indicator of genetic links, degree of fractionation, and rare-metal potential of granites. Greisen Sn, W, Mo, and Be deposits are expected to accompany granites with Zr/Hf < 25, whereas granites related to Ta deposits should have Zr/Hf < 5.

As the level of interest in aging research increases, there is a growing number of geroprotectors, or therapeutic interventions that aim to extend the healthy lifespan and repair or reduce aging-related damage in model organisms and, eventually, in humans. There is a clear need for a manually-curated database of geroprotectors to compile and index their effects on aging and age-related diseases and link these effects to relevant studies and multiple biochemical and drug databases. Here, we introduce the first such resource, Geroprotectors (http://geroprotectors.org). Geroprotectors is a public, rapidly explorable database that catalogs over 250 experiments involving over 200 known or candidate geroprotectors that extend lifespan in model organisms. Each compound has a comprehensive profile complete with biochemistry, mechanisms, and lifespan effects in various model organisms, along with information ranging from chemical structure, side effects, and toxicity to FDA drug status. These are presented in a visually intuitive, efficient framework fit for casual browsing or in-depth research alike. Data are linked to the source studies or databases, providing quick and convenient access to original data. The Geroprotectors database facilitates cross-study, cross-organism, and cross-discipline analysis and saves countless hours of inefficient literature and web searching. Geroprotectors is a one-stop, knowledge-sharing, time-saving resource for researchers seeking healthy aging solutions.

The results of the comparative quantitative study of oxygen-containing groups adsorbed on the surface of carbonized sponge scaffold (CSS), highly oriented pyrolytic graphite (HOPG), fullerite C60 and multi-walled carbon nanotubes (MWCNTs) introduced into a high vacuum from the atmosphere without any pre-treatment of the surface are discussed. The studied materials are first tested by XRD and Raman spectroscopy, and then quantitatively characterized by XPS and NEXAFS. The research results showed the presence of carbon oxides and water-dissociation products on the surfaces of materials. It was shown that main source of oxygen content (~2%) on the surface of HOPG, MWCNTs, and C60 powder is water condensed from the atmosphere in the form of an adsorbed water molecule and hydroxyl group. On the CSS surface, oxygen atoms are present in the forms of carbon oxides (4–5%) and adsorbed water molecules and hydroxyl groups (5–6%). The high content of adsorbed water on the CSS surface is due to the strong roughness and high porosity of the surface.

In this study, the Holocene development of a peat plateau area in the east-European Russian Arctic is reconstructed based on detailed macrofossil, physico-chemical and radiocarbon analyses from two peat sequences. Basal dates from these two, c. 2 m long, peat profiles are c. 9420 BP and c. 9250 BP. From another six peat sequences gross-stratigraphic descriptions and additional radiocarbon dates are available. Basal dates from two short (&lt;1 m) peat profiles indicate further peatland expansion at c. 3635 BP and c. 1285 BP. The oldest macrofossils of tree birch are dated to c. 9500 BP and those of conifers, presumably spruce, to c. 8000 BP. Tree stands became rare in the study area after c. 2800 BP, but occasionally occur until present. Peatlands formed through terrestrialization of ponds or paludification of forested uplands. Between 9000 and 3100 BP the peatlands were wet rich fens. Beginning from c. 3100 BP there are marked changes in their surface hydrology, connected with climatic cooling and permafrost aggradation. Sphagnum species started to play a dominant role. Permafrost aggradation at the six peat plateau sites is tentatively dated to c. 3100 BP, c. 2200 BP and &lt;600 BP. Nowadays the area is mostly dry peat plateau with interspersed thermokarst lakes. Generally, peat accumulation rates are lower in the upper layers, which consist mostly of Sphagnum peat, than in the lower layers of sedge/brown moss peat. This is most probably due to ceased accumulation or even erosion in the currently widespread dry lichen stage in the peat plateau. Very high accumulation rates are recorded from moist sites with incipient permafrost. This study supports previous multiproxy climate reconstructions in the area according to which temperatures were at least 2-3°C higher during the mid-Holocene compared to present.

amorphous carbons is considered from the viewpoint of graphene domains presenting their basic structure units (BSUs) in terms of molecular spectroscopy. The molecular approximation allows connecting the characteristic D-G doublet spectra image of one-phonon spectra with a considerable dispersion of the C=C bond lengths within graphene domains, governed by size, heteroatom necklace of BSUs as well as BSUs packing. The interpretation of 2D two-phonon spectra reveals a particular role of electrical anharmonicity in the spectra formation and attributes this effect to a high degree of the electron density delocalization in graphene domains. A size-stimulated transition from molecular to quasi-particle phonon consideration of Raman spectra was experimentally traced, which allowed evaluation of a free path of optical phonons in graphene crystal.

Ionic thermoelectric (i-TE) material with mobile ions as charge carriers has the potential to generate large thermal voltages at low operating temperatures. This study highlights the role of ions in i-TE hydrogels employing a poly(vinyl alcohol) (PVA) polymer matrix and a number of ion providers, e.g., KOH, KNO3, KCl, KBr, NaI, KI, and CsI. The relationship between the intrinsic physical parameters of the ion and the thermoelectric performance is established, indicating the ability to influence the hydrogen bond by the ion is a crucial factor. Among these i-TE hydrogels, the PVA/CsI hydrogel exhibits the largest ionic Seebeck coefficient, reaching 52.9 mV K–1, which is the largest of all i-TE materials reported to date. In addition, our work demonstrates the influence of ions on polymer configuration and provides an avenue for ion selection in the Soret effect in ionic thermoelectrics.

Abstract Pricaspian basin geology is reviewed in the light of 500,000 km of seismic profiles and several thousand wells. We focus on how hydrocarbons from three sources accumulated in relation to the 1800 salt structures in a basin that changed little in planform from the Devonian to the Paleogene. Riphean to Carboniferous shelf sedimentary strata are still flat lying between a poorly known crystalline basement and a base of salt now 10 km deep. Slow and almost continuous sedimentation in the basin center downbuilt huge massifs in Permian salt initially 4.5 km thick. Basin sediments are flat lying or backtilted between down-to-basin growth faults along northern and western margins starved of sediments. By contrast, progradation of Permian sediments from the Urals, Triassic sediments from the South Emba shear zone, and Jurassic sediments from the Dombass-Tuarkyr fold belt downbuilt successive waves of salt structures basinward from margins in the east, southeast and then the south. A zone of salt overhangs records extrusion that starved basin-marginal salt structures, particularly during a basinwide hiatus in the Early Jurassic. Salt diapirs along polygonal normal faults rooting to the crests of still-potent salt structures through Cretaceous–Paleogene strata indicate that salt upbuilt back to the surface and resumed downbuilding. Coarse clastic fans infill deep canyons incised across the basin by rivers draining to the Caspian in Pliocene times.

-methoxyphenylamine)-9,9'-spirobifluorene (spiro-OMeTAD), as an organic small molecule material, is the most commonly employed hole transport material (HTM) in perovskite solar cells (PSCs) because of its excellent properties that result in high photovoltaic performances. However, the material still suffers from low conductivity, leading to the necessary use of dopants and oxidative processes to overcome this issue. The spiro-OMeTAD oxidation process is highlighted in this review, and the main parameters involved in the process have been studied. Furthermore, the best alternatives aiming to improve the spiro-OMeTAD electrical properties have been discussed. Lastly, this review concludes with suggestions and outlooks for further research directions.

Research Article| August 01, 2011 Baltica in the Cordillera? E.L. Miller; E.L. Miller * 1Department of Geology and Environmental Science, Stanford University, Stanford, California 94305, USA *E-mails: elmiller@stanford.edu; kouznikbor@mail.ru; soboleva@geo.komisc.ru; udoratina@geo.komisc.ru; mjgrove@stanford.edu; ggherels@geo.arizona.edu. Search for other works by this author on: GSW Google Scholar N. Kuznetsov; N. Kuznetsov * 2Geological Institute, Russian Academy of Sciences, Moscow 119017, Russia *E-mails: elmiller@stanford.edu; kouznikbor@mail.ru; soboleva@geo.komisc.ru; udoratina@geo.komisc.ru; mjgrove@stanford.edu; ggherels@geo.arizona.edu. Search for other works by this author on: GSW Google Scholar A. Soboleva; A. Soboleva * 3Institute of Geology, Komi Scientific Center, Uralian Branch of the Russian Academy of Sciences, Syktyvkar 167982, Russia *E-mails: elmiller@stanford.edu; kouznikbor@mail.ru; soboleva@geo.komisc.ru; udoratina@geo.komisc.ru; mjgrove@stanford.edu; ggherels@geo.arizona.edu. Search for other works by this author on: GSW Google Scholar O. Udoratina; O. Udoratina * 3Institute of Geology, Komi Scientific Center, Uralian Branch of the Russian Academy of Sciences, Syktyvkar 167982, Russia *E-mails: elmiller@stanford.edu; kouznikbor@mail.ru; soboleva@geo.komisc.ru; udoratina@geo.komisc.ru; mjgrove@stanford.edu; ggherels@geo.arizona.edu. Search for other works by this author on: GSW Google Scholar M.J. Grove; M.J. Grove * 1Department of Geology and Environmental Science, Stanford University, Stanford, California 94305, USA *E-mails: elmiller@stanford.edu; kouznikbor@mail.ru; soboleva@geo.komisc.ru; udoratina@geo.komisc.ru; mjgrove@stanford.edu; ggherels@geo.arizona.edu. Search for other works by this author on: GSW Google Scholar G. Gehrels G. Gehrels * 4Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA *E-mails: elmiller@stanford.edu; kouznikbor@mail.ru; soboleva@geo.komisc.ru; udoratina@geo.komisc.ru; mjgrove@stanford.edu; ggherels@geo.arizona.edu. Search for other works by this author on: GSW Google Scholar Geology (2011) 39 (8): 791–794. https://doi.org/10.1130/G31910.1 Article history received: 13 Nov 2010 rev-recd: 18 Mar 2011 accepted: 28 Mar 2011 first online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation E.L. Miller, N. Kuznetsov, A. Soboleva, O. Udoratina, M.J. Grove, G. Gehrels; Baltica in the Cordillera?. Geology 2011;; 39 (8): 791–794. doi: https://doi.org/10.1130/G31910.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract U-Pb ages of detrital zircon suites from Paleozoic strata in the Arctic Alaska–Chukotka terrane (AAC), Alexander terrane, northern Sierra terrane, and eastern Klamath terrane of the North American Cordillera suggest an exotic Gondwana or Baltic origin. We evaluate these hypotheses with U-Pb ages of detrital zircon suites from Cambrian–Devonian strata of northern Baltica. Precambrian zircon populations (ca. 0.8–3.0 Ga) from Baltica compare well with similar age detritus in the AAC and Cordilleran terranes, but the amount and age of younger Neoproterozoic and Ordovician–Silurian components are variable. The AAC shares its stratigraphy with Baltica and has the most similar detrital zircon suites. Closing the Arctic places the AAC against the Lomonosov Ridge and the edge of Baltica in pre-Cretaceous time. After the Caledonian orogeny and before the Ural Mountains formed, the Baltica, AAC, and Cordilleran margins shared a Devonian–Carboniferous rift history and became along-strike portions of a Carboniferous–Permian continental margin. This rifting event might have been responsible for the initial separation of Baltica and Caledonian affinity terranes from this margin. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

The aim of this study was to evaluate the effects of chronotype and social jetlag (SJL) on intelligence. Subjects were aged 14–25 years (n = 1008). A significant effect of intelligence on academic performance, as measured by the Raven’s Standard Progressive Matrices test, was found (F2,917 = 11.75, P < 0.0001, η2 = 0.03). When SJL was less than 2 hours, the intelligence of people with late chronotype was found to be higher than that of subjects with early and intermediate chronotypes (F2,305 = 3.12, P < 0.05, η2 = 0.02). A negative effect of SJL on the results of intelligence testing was noted only in subjects with late chronotype (F2,536 = 2.61, P < 0.05, η2 = 0.02). Our data suggest that people with late chronotype have a higher level of intelligence, but these advantages disappear when SJL ≥2 hours.

An infiltration test was performed from a ditch with the purpose of monitoring the evolution of the piezometric levels using self‐potential measurements made at the ground surface. We used a set of 18 piezometers and a network of 41 nonpolarizable (Pb/PbCl 2 ) electrodes. The variations of the self‐potential signals are linearly correlated to the piezometric level changes with an apparent voltage coupling coefficient of −5.5 ± 0.9 mV m −1 . We measured, independently of this infiltration test, the three material properties entering the macroscopic field equations. They are the resistivity distribution of the soil, its mean hydraulic conductivity, and its intrinsic streaming potential coupling coefficient (−5.8 ± 1.1 mV m −1 ). Then, we modeled numerically the infiltration test and the associated self‐potential signals using a two‐dimensional finite difference code. The numerical model reproduces fairly well the observed results. This investigation demonstrates the effectiveness of the self‐potential method in field conditions to monitor small variations (&lt;0.60 m) of the water table. It offers for the first time a test of the electrokinetic theory in the field with independent evaluation of the material properties entering the field equations.