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By using P and S wave receiver functions and P and S wave travel time residuals, we have found velocity models for 16 seismograph stations in Eastern Anatolia. Our study is focused mainly on the mantle lithosphere, asthenosphere and transition zone. The volcanism and uplift of the Eastern Anatolia Plateau are thought to be related to the Bitlis slab break off and delamination of the continental lithosphere. Sinking cold slab and lithospheric drips can reduce temperature in the mantle transition zone (MTZ) by up to a few hundred degrees C. However, our analysis of seismic data provides no robust evidence of significant cooling of the transition zone. In the mantle immediately above the 410-km discontinuity there is a pronounced low S wave velocity layer that may be a source of the volcanism in the study region. Another low velocity layer is present at the base of the MTZ. The obtained S wave velocity models of the upper mantle can be divided into three groups. In the first group, the lithosphere-asthenosphere boundary (LAB) is at a depth of similar to 60 km. In the second group, the LAB is at a depth from 90 to 100 km. In the third group, the mantle lithosphere is practically absent. On a scale of our analysis there is no clear correspondence between the obtained mantle velocity models and the volcanism (< 23 Ma) exposed at the surface. Only the models of the first group are well represented in the neighboring Central Anatolian Plateau.

ImportanceEconomic and racial inequality is linked to disparities in children’s mental health. Biomarkers that reflect these social disparities are lacking.ObjectiveWe examined the hypothesis that salivary DNA-methylation patterns of higher inflammation and faster pace of biological aging are economically, racially and ethnically stratified and are associated with child mental health.DesignThe Texas Twin Project is an on-going, observational, longitudinal study that began in May 2012. Analyses were preregistered on May 7, 2021, and completed on August 23, 2021.SettingThe population-based study identified and recruited participants from public school rosters in the greater Austin area.ParticipantsParticipants in the analytic data set included all participants that agreed to contribute DNA samples and whose samples were assayed by January 2021.ExposuresFamily- and neighborhood-level socioeconomic inequality, racial and ethnic identities (White, Latinx, Black, Asian).Main Measure(s)Environmental exposures were analyzed in relation to salivary DNA- methylation profiles of higher inflammation (DNAm-CRP) and faster pace of biological aging (DunedinPoAm). Child internalizing problems, attention problems, aggression, rule-breaking, ADHD, oppositional defiant disorder, and conduct disorder were measured using parent-reports and self-reports on abbreviated versions of the Achenbach Child Behavior Checklist and Conners 3.The hypotheses being tested were formulated after data collection of the present data freeze and were pre-registered prior to analyses being conducted.ResultsIn a sample of N=1,183 8-to-19-year-olds (609 female, age M=13.38y), children’s salivary DNA-methylation profiles and psychiatric symptoms differed by socioeconomic conditions, race and ethnicity. Children with more parent-reported internalizing symptoms had higher DNAm-CRP (r=0.15, 95% CI=0.05 to 0.25, P=0.004) and DunedinPoAm (r=0.15, CI=0.05 to 0.25, P=0.002), and children with more parent-reported aggression problems had higher DNAm-CRP (r=0.17, CI=0.04 to 0.31, P=0.013). DNAm-CRP partially mediated advantage of higher family socioeconomic status (16% of total effect) and White racial identity (12% of total effect) on reduced internalizing symptoms. DunedinPoAm also partially mediated advantage of White racial identity on internalizing (19% of total effect).Conclusions and RelevanceSocioeconomic and racial inequality are visible in children’s epigenetic profiles of inflammation and the rate of biological aging in a manner that is tied to social disparities in mental health.Key PointsQuestionWe examined whether salivary DNA-methylation profiles are socially stratified and associated with child mental health.FindingsIn this preregistered, cross-sectional observational study of 1,183 children and adolescents, socioeconomic, racial, and ethnic disparities in mental health were associated with salivary DNA-methylation profiles of inflammation and the pace of biological aging.MeaningDNA-methylation biomarkers hold promise as tools to quantify the biological impact of socioeconomic inequality and being racially minoritized in a manner that is tied to social disparities in mental health.

Children’s cognitive functioning and educational performance are socially stratified. Social inequality, including classism and racism, may operate partly via epigenetic mechanisms that modulate neurocognitive development. Following preregistered analyses of data from 1,183 8-to 19-year-olds from the Texas Twin Project, we examined whether salivary DNA-methylation measures of inflammation (DNAm-CRP), cognitive functioning (Epigenetic-g), and pace of biological aging (DunedinPoAm) are socially stratified and associated with performance on tests of cognitive functions. We find that children growing up in more disadvantaged families and neighborhoods and children from marginalized racial/ethnic groups exhibit DNA-methylation profiles associated with higher chronic inflammation, lower cognitive functioning, and faster pace of biological aging. These salivary DNA-methylation profiles were associated with processing speed, general executive function, perceptual reasoning, verbal comprehension, reading, and math. Given that the DNA-methylation measures we examined were originally developed in adults, our results suggest that social inequalities may produce in children molecular signatures that, when observed in adults, are associated with chronic inflammation, advanced aging, and reduced cognitive function. Salivary DNA-methylation profiles might be useful as a surrogate endpoint in assessing the effectiveness of psychological and economic interventions that aim to reduce negative effects of childhood social inequality on lifespan development.Significance StatementChildren’s cognitive functioning differs by dimensions of social inequality, such as class and race. Epigenetic mechanisms that regulate gene expression might be critically involved in the biological embedding of environmental privilege and adversity. We find that children growing up in more disadvantaged families and neighborhoods and from marginalized racial/ethnic groups exhibit higher chronic inflammation, lower cognitive functioning, and a faster pace of biological aging, as indicated by novel salivary DNA-methylation measures. These DNA-methylation measures of higher inflammation, lower cognitive functioning, and a faster pace of biological aging were, in turn, associated with performance on multiple cognitive tests. DNA-methylation measures might be useful as a surrogate endpoint in evaluation of programs to address the childhood social determinants of lifelong cognitive disparities.

P and S receiver functions from seismograph stations in the Indian shield, Western Himalaya, Ladakh and Tibet are processed with a method which provides estimates of the P and S velocities and their ratio as a function of depth. The time difference between the P660s and P410s phases in the north of the Indian shield and the Lesser Himalaya is 1.0–1.5 s larger than the normal 24 s. This is an effect of a low temperature with implication that the consumed material of the Indian shield has reached the transition zone. The waveforms of the P410s and S410p phases at some stations in the Indian shield are indicative of a thin (a few tens of kilometers) low S velocity layer atop the 410-km discontinuity, which is usually related to mantle upwelling. The mantle S velocity under the Indian shield at depths less than 180 km is 4.4–4.5 km/s, much lower than the 4.7 km/s, typical for Precambrian shields. We explain this low S velocity mainly by a recent (Tertiary?) metasomatic alteration of the high-velocity mantle keel. Beneath the western Himalaya, Ladakh and western Tibet (but not eastern Tibet) the S velocity in the mantle at depths less than 100–150 km is around 4.7 km/s, Vp/Vs is anomalously low, and we argue that this high-velocity layer is a remnant of the mantle lithosphere of the northern Greater India. At most locations in the Indian shield high S velocities (3.5 km/s and more) are dominant in the middle and lower crusts, and the elevated S velocity is accompanied by an increased Vp/Vs ratio (1.8–2.1 versus the standard 1.73). In the foothills of the Himalaya, the crust is 50–55 km thick and consists almost entirely of a high-S-velocity (3.7 km/s and more) rock with the increased Vp/Vs ratio in the middle and the standard Vp/Vs ratio in the lower crust. This observation suggests that the upper crust of the Indian plate is scraped off in the collision zone, whereas the high-velocity lower crust is subducted jointly with the mantle lithosphere. The high velocities are responsible for the P-wave teleseismic travel time anomaly of ~ 1 s relative to Ladakh. Under the Himalaya the Vp/Vs ratio in the crust is normal, which suggests a change in composition relative to the crust of the Indian shield. Under Ladakh and Tibet the anomalously high Vp/Vs ratio in the crust is observed again. Beneath Tibet our analysis reveals a low-velocity crustal zone of partial melt between the 20-km and 45-km depths. Previously, the 45-km discontinuity was interpreted as the effect of eclogitization.

SUMMARY To understand deep structure and processes beneath southern Africa, we apply the doublestacking version of the S receiver function (SRF) technique to the recordings of the South African Seismic Experiment. In this technique the wavefields of S and SKS are separated by space–time filtration, and the receiver functions are constructed separately for the S and SKS seismic phases. The results are consistent with those obtained from the SRFs of the permanent stations BOSA and LBTB. Evidence for a reduced S velocity atop the 410-km discontinuity is present in both SRFs and P receiver functions: the S velocity contrast at the 410-km discontinuity is ∼40 per cent larger than the norm, and there are observations of S350p and P350s seismic phases from the negative 350-km discontinuity beneath the Kaapvaal craton. The S350p and P350s phases display a dependence on the azimuth, which can be caused by anisotropy in the layer atop the 350-km discontinuity. This dependence is consistent with observations of shear wave splitting in SKS. There are observations of the S450p phase from the 450-km negative discontinuity in the transition zone. The most anomalous transition zone is found close to the region where the Kalahari craton was located in the Mesozoic. Lateral variations of the S velocity are found beneath the 660-km discontinuity. Teleseismic S and P traveltime residuals with respect to IASP91 model are evaluated from the traveltimes of the P410s and Pp410s seismic phases. In the uppermost mantle these residuals as well as S410p traveltimes require a reduced VP/VS ratio (around 1.75 ± 0.01 versus 1.8 in IASP91), an effect of the depletion of the mantle lithosphere in basaltic material. In the models obtained by a joint inversion of the receiver functions and the teleseismic traveltime residuals the low velocity zone (LVZ) with the onset of low velocity at a depth of ∼140 ± 20 km is present at most locations. The minimum S velocity in the LVZ is ∼4.5 km s −1 . The LVZ in our models is consistent with the S velocity, VP/VS velocity ratio and depth range of high-temperature lerzholites in the mantle xenoliths from southern Africa. Our most intriguing finding is a very low quality factor QS (on the order of a few tens) in the upper mantle. We interpret high attenuation, the LVZ and the low S velocity atop the 410-km discontinuity as the effects of plume-like phenomena in the upper mantle.

The Archean Dharwar craton in south India is known for long time to be different from most other cratons. Specifically, at station Hyderabad (HYB) the Ps converted phases from the 410- and 660-km mantle discontinuities arrive up to 2 s later than in other cratons of comparable age, which implies lower upper mantle velocities. To resolve the unique lithosphere-asthenosphere system of the Dharwar craton, we inverted jointly P and S receiver functions and teleseismic P and S traveltime residuals at 10 seismograph stations. This method operates in the same depth range as long-period surface waves but differs by much higher lateral and radial resolution. We observe striking differences in crustal structures between the eastern and western Dharwar craton (EDC and WDC, respectively): crustal thickness is of around 31 km, with predominantly felsic velocities, in the EDC and of around 55 km, with predominantly mafic velocities, in the WDC. In the mantle we observe significant variations in the P velocity with depth, practically without accompanying variations in the S velocity. In the mantle S velocity there are azimuth-dependent indications of the Hales discontinuity at a depth of similar to 100 km. The most conspicuous feature of our models is the lack of the high velocity mantle keel with the S velocity of similar to 4.7 km s(-1), typical of other Archean cratons. The S velocity in our models is close to 4.5 km s(-1) from the Moho to a depth of similar to 250 km. There are indications of a similar upper mantle structure in the northeast of the Indian craton and of a partial recovery of the normal shield structure in the northwest. A division between the high S-velocity western Tibet and low S-velocity eastern Tibet may be related to a similar division between the northeastern and northwestern Indian craton.

International audience; A thin, low-S-velocity layer atop the 410-km discontinuity is an intriguing feature of the upper mantle with important implications for geodynamics, but relevant seismic data are few. By applying S receiver function technique to more than 50 globally distributed stations, in 10 regions we obtain evidence for a negative discontinuity at a depth of about 350 km. In most cases, the low velocity is found beneath Precambrian platforms, in association with either Mesozoic or Cenozoic mantle plumes. This relationship suggests dehydration of water-bearing silicates as a possible reason for the low velocity, but contradicts the predictions of the transition-zone-water-filter model of Bercovici and Karato (Nature 425, 39-44, 2003). The presence of the low velocity beneath some Mesozoic traps, in spite of plate motions, implies the possibility of coupling of the continental lithosphere and the underlying upper mantle up to a depth of not, vert, similar 400 km.

SUMMARY The fate of the mantle lithosphere of the Indian Plate in the India‐Eurasia collision zone is not well understood. Tomographic studies reveal high P velocity in the uppermost mantle to the south of the western Himalaya, and these high velocities are sometimes interpreted as an image of subducting Indian lithosphere. We suggest that these high velocities are unrelated to the ongoing subduction but correspond to a near-horizontal mantle keel of the Indian shield. In the south of the Indian shield upper-mantle velocities are anomalously low, and relatively high velocities may signify a recovery of the normal shield structure in the north. Our analysis is based on the recordings of seismograph station NIL in the foothills of the western Himalaya. The T component of the P receiver functions is weak relative to the Q component, which is indicative of a subhorizontally layered structure. Joint inversion of the P and S receiver functions favours high uppermost mantle velocities, typical of the lithosphere of Archean cratons. The arrival of the Ps converted phase from 410 km discontinuity at NIL is 2.2 s earlier than in IASP91 global model. This can be an effect of remnants of Tethys subduction in the mantle transition zone and of high velocities in the keel of the Indian shield. Joint inversion of SKS particle motions and P receiver functions reveals a change in the fast direction of seismic azimuthal anisotropy from 60 ◦ at 80‐160 km depths to 150 ◦ at 160‐220 km. The fast direction in the lower layer is parallel to the trend of the Himalaya. The change of deformation regimes at a depth of 160 km suggests that this is the base of the lithosphere of the Indian shield. A similar boundary was found with similar techniques in central Europe and the Tien Shan region, but the base of the lithosphere in these regions is relatively shallow, in agreement with the higher upper-mantle temperatures. The ongoing continental collision is expressed in crustal structure: the crust beneath NIL is very thick (58 ± 2 km), and the S velocity in the intermediate and lower crust is around 4.0 km s −1 . This anomalously large velocity and thickness can be explained by scraping off the lower crust, when the Indian lithosphere underthrusts the Himalaya.

SUMMARY Azimuthal anisotropy in the upper mantle of many continental regions is documented by Swave splitting measurements with SKS techniques. Here we present observations of splitting of the SKS seismic phase at seismograph stations in the Siberian platform, where few such data were known previously. The parameters of splitting are coherent: the fast direction everywhere is around 150 ◦ , and the delay of the slow split wave is close to 1.0 s. These observations provide no constraints on the distribution of anisotropy with depth. However, the Siberian platform is remarkable in that it is covered by a network of long-range profiles, where P waves from nuclear explosions are recorded at epicentral distances of 2000 km and more. Depending on epicentral distance these waves sample the upper mantle from the Moho to the transition zone. Two profiles run approximately parallel to the fast direction of the azimuthal anisotropy, whereas the directions of the two others are intermediate between the fast and slow. We examine the observed P traveltimes for their dependence on the azimuth and epicentral distance. With the available data on elastic anisotropy in mantle xenoliths, the values of P-wave anisotropy for horizontal propagation can be used to evaluate S-wave splitting for vertical propagation. It appears that the upper mantle between the Moho and 150 km depth is responsible for not more than about 30 per cent of the large-scale effect in the SKS phase. The major effect is accumulated in a broad low-velocity zone, the top of which is found at a depth of 150 km. Anisotropy within this zone can be caused by recent mantle flow. A similar distribution with depth might explain discrepancies between the estimates of azimuthal anisotropy from phase velocities of surface waves and SKS splitting in North America and South Africa.

Theoretical investigations of some dynamic properties of a railway vehicle with wheelsets of differential rotation having a clearance between a wheel center and a rim were carried out. Estimation of motion stability has been performed. Relations of a friction coefficient with a moment in a rimwheel center connection and an angular velocity of revolution were established. Results of the modeled wear tests are shown.

Summary Seismic stratification of the upper mantle is investigated by applying two complementary techniques to the records of the Graefenberg array in southern Germany. The anisotropic P receiver function technique (Kosarev et al. 1984; Vinnik & Montagner 1996) is modified by using summary seismic events instead of individual events and different weighting functions instead of the same function for the harmonic angular analysis of the SV and T components of the Pds phases. The summary events provide better separation of the second azimuthal harmonic than the individual events. The parameters of the second harmonics of SV and T thus evaluated should be similar if they reflect the effects of azimuthal anisotropy. This can be used as a criterion to identify the anisotropy. To detect the Sdp phases and their azimuthal variations caused by azimuthal anisotropy we have developed a stacking technique, which can be termed the S receiver function technique It includes axis rotation to separate interfering P and S arrivals, determination of the principal (M) component of the S-wave motion, deconvolution of the P components of many recordings by their respective M components and stacking of the deconvolved P components with weights depending on the level of noise and the angle between the M direction and the backazimuth of the event. Both techniques yield consistent results for the Graefenberg array. As indicated by the P receiver functions, the upper layer of the mantle between the Moho and 80 km depth is anisotropic with dVs/Vs around 0.03 and the fast direction close to 20° clockwise from north. The fast direction of anisotropy below this layer is around 110°, The boundary between the upper and the lower anisotropic layers is manifested by the detectable Pds and Sdp converted phases. Shear wave splitting in SKS is strongly dominated by azimuthal anisotropy in the lower layer (asthenosphere).

A new hypothesis for friction forces between two elastic bodies is proposed. The hypothesis is based on contact mechanics problem. The study concentrates on the problem of a railway wheel rolling on rail under tractive effort and normal load. The effect of friction force in developing adhesion is considered. Based on the proposed hypothesis, new design of a railway wheelset has been developed and tested on Moscow Metro and tramcar.

The D″ shell at the base of the Earth's mantle is thought to be a thermal and compositional boundary layer where vigorous dynamical processes are taking place1,2,3,4. An important property of D″ is its seismic anisotropy, expressed as different velocities for horizontally and vertically polarized shear waves that have been diffracted or reflected at the core–mantle boundary5,6. The nature of this anisotropy has been the subject of debate7,8,9,10,11. Here we present an analysis of various seismic phases, generated in the Kermadec–Fiji–Tonga zone and recorded at stations in North America, which reveal a region at the base of the mantle beneath the southwest Pacific Ocean where horizontally propagating vertically polarized waves are slower (by at least 10 per cent) than horizontally polarized waves. This observed anisotropy is an order of magnitude larger than that previously thought to exist in the lower mantle, and corresponds to lateral variations in horizontally polarized shear-wave velocity which are also of about 10 per cent. We speculate that this anisotropy may be the result of the mixing and shearing of strongly heterogeneous material in the boundary layer.

Accepted 1995 May 12. Received 1995 May 4; in original form 1995 March 6. In a recent paper, Gurrola, Minster & Owens (1994; hereafter referred to as GMO) introduced a technique for the analysis of seismic data and applied it to the records of station OBN in Russia. GMO claimed that this was a new technique in earthquake seismology, and that their results for OBN provided a new insight into the deep structure of the Russian platform. We have some comments on their techniques and results.

Seismic estimates of sharpness of the mantle discontinuities are important for constraining models of composition and temperature in the deep Earth but these data are difficult to obtain. We explore a possibility to determine sharpness of the major mantle discontinuities (those at depths around 400 and 650 km) from the broad-band records of phases converted from P to S underneath the receiver. Our estimates are obtained from a comparative analysis of waveforms of the converted phases and those of the P waves in the teleseismic records of BRV (Kazakhstan), GRF (Germany), NRE0 (Norway) and YKW (Canada). The data indicate that the shape of the pulse converted at the 400-km discontinuity is close to that of the P wave whereas the pulse of the 650-km conversion is substantially broader. We infer from this comparison that the 400-km discontinuity is sharp (width of the transition zone is less than 5–7 km). The 650-km transition is modelled by a linear gradient zone 20–30 km thick.

In the records of the Graefenberg observatory and of a few other stations we have detected long-period SH reflections at the underside of mantle discontinuities. The bounce points of the reflections are located in the north-western margins of the Pacific. The data are used to evaluate S660S-S410S differential times which are directly related to the thickness of the layer between the two discontinuities. Most of the bounce points are in the area of the Japan and Kuril-Kamchatka subduction zones where a large-scale depression of the 660-km discontinuity was previously found and attributed to a cooling effect of subduction [Shearer & Masters, 1992]. According to our data the differential time in this region is 3 s less than in the IASP91 model. This anomaly suggest a thinning of the layer between the two discontinuities instead of thickening which is expected from depression of the lower discontinuity. Our analysis also indicates that there is a strong reflector in the study region a depth of 900 km.

We describe a technique for measuring shear wave splitting in the mantle of the oceans and poorly instrumented continental regions. The idea of the method is to analyse evolution of the form of the particle motion in the long-period multiple ScS and sScS phases as a function of the order of reflection. The differential motion is inverted into the parameters of azimuthal anisotropy. The technique is applied to the digital recordings of events from the Tonga-Kermadek seismic zone at station AFI. It is found that the fast direction of anisotropy in the mantle beneath the Pacific plate is close to the present day absolute-velocity direction of the plate.

The transition zone differs from the rest of the mantle by high positive P and S wave velocity gradients. However, by applying S receiver function technique to recordings of about 50 globally distributed stations, in 7 regions we obtain evidence of negative discontinuity at a depth around 500 km. Four of these regions correspond to the well known hotspots. No other hotspots are sampled by our observations at this depth. Our modeling suggests that the negative discontinuity is hardly an effect of anisotropy of wadsleyite. More likely, it is caused by isotropic S velocity reduction of around 0.2 km/s. Origin of the low velocity can be related to enhanced water content in wadsleyite.

[1] The Lehmann discontinuity in the upper mantle is often interpreted as a boundary separating anisotropic and isotropic media. We demonstrate, however, that seismic anisotropy plays, if any, a minor role in the origin of the Lehmann discontinuity. Our data are obtained with S receiver function technique from recordings of the MOMA seismograph array in the eastern USA. Part of the data is processed with a new modification of this technique. We observe Sp phase converted from the Lehmann discontinuity at a depth around 200 km with comparable amplitudes and similar polarities in two azimuths differing by about 90°. Contrary to the observations, the polarity in the synthetic seismograms for models with azimuthal anisotropy is opposite for the azimuths differing by 90°. Radial anisotropy with a slow vertical direction results in the Sp phase with the polarity opposite to the observed one.

[1] We investigated deep structure of the Afro-Arabian hotspot by using recordings from Geoscope seismograph station ATD. The records are processed with the S receiver function technique, which allows a detection of Sp converted phases from the upper mantle discontinuities. The seismic data reveal two unusual discontinuities. The discontinuity at a depth of 160 km beneath the Gulf of Aden corresponds to the onset of melting. If the water content in olivine is around 800 H/106Si, melting at this depth requires a temperature close to 1550°C, about 120°C higher than the average. Another remarkable discontinuity is found at a depth of 480 km, where S velocity drops with depth by about 0.2 km/s. This can be the head of another plume which is trapped in the mantle transition zone.

[1] S and P receiver functions reveal indications of a low S velocity layer at 350–410 km depths beneath the Arabian plate. A similar layer was previously found beneath the Kaapvaal craton in southern Africa and Tunguska basin of the Siberian platform. We hypothesize, that the boundary at 350 km depth may separate dry mantle root of the Arabian plate from the underlying wet mantle layer. This boundary is not found beneath the Gulf of Aden, where the root is destroyed by sea-floor spreading.

Measurements of shear-wave splitting represent an important tool for determining seismic anisotropy and for quantifying deformation processes in the Earth. Wookey et al.1 claim to have observed significant seismic anisotropy in the mid-mantle between the Tonga–Kermadec subduction zone and Australia. We argue that their results are likely to be methodological artefacts and that the available data can be explained by moderate anisotropy in the upper mantle close to the seismograph stations. The lack of evidence for anisotropy in the mid-mantle nullifies any related geodynamic inferences.

An electric-discharge x-ray preionized XeCl laser operating in an unswitched regime was developed and the dependence of its output characteristics on the pump power was investigated. An output energy per pulse of 15 J was obtained with an efficiency of 2.4% from a 4.3-liter active volume.

An investigation was made of the conditions under which control was possible of a narrowband XeCl laser with injection locking when the duration of the output pulses of this laser was 60 nsec and the duration of an external signal was 15 nsec. A definition of the efficiency of injection locking of an XeCl laser was introduced. It was found that this efficiency reached 95% when the intensity of the external control signal was ~2 W/cm2, but the efficiency fell to zero when the intensity was 7 mW/cm2. The output power of the laser exceeded 100 kW and the divergence was within 0.15 mrad when the spectral line width was 5 pm.

The sensitivity of different mouse strains to Str. pneumoniae, serotype 6, under the conditions of intraperitoneal and intranasal infection has been studied. The time course of distribution of pneumococci in the organs has been shown and differences depending on the methods of infection have been revealed. The pathomorphological and immunomorphological changes in the organs and tissues after the introduction of the infective agent by different methods have been established.

The sensitivity of different mouse strains to Str. pneumoniae, serotype 3, after the intraperitoneal injection of the infective agent was studied. These experiments revealed that the animals under study, so far as their susceptibility and sensitivity were concerned, formed a single group, highly sensitive to this serotype. The sublethal dose of the pneumococcus was determined. The distribution of pneumococci in the organs during a definite time interval was shown and the fact of the prolonged carriership of the capsular forms of the pneumococci was established.

The possibility of using the experimental-analytical balance method (EABM) for development of balanced media, optimal and economic by their composition is shown. The method is based on the specific growth activity of the medium components and mathematical calculation of their concentrations. A balanced medium containing human placenta hydrolysate was developed. The medium has a high component consumption coefficient and provides maintenance of high levels of the pneumococcal culture biological properties such as growth, capsule formation, virulence and agglutinability. The quantities of nutrient yeast extract, cystine, glucose and sodium chloride in the balanced medium are 2, 18-20, 4-4.7 and 32-33 times lower respectively than those in the initial medium. The use of the balanced medium instead of the initial unbalanced one or instead of the meat medium based on the Hottinger broth will provide the total economy of 1010 or 2360-2580 roubles respectively per. 1000 liters of the medium. It is concluded that a wider use of this method in optimization of microbiological nutrient media in production of medical and biological preparations is promising.

The possibility of the pneumococcal cross infection of guinea pigs in experimental conditions, the time course of the distribution of pneumococci in their organs, and the duration, within the time limits of the experiment, of persistence of the given infective agent were studied. Normal animals placed in the same room with infected ones were shown to become the carriers of definite pneumococcal serotypes. As a result, these studies revealed that nasopharyngeal carriership and infection of different organs were not directly interrelated and the method of infection of guinea pigs did not influence the time course of distribution of pneumococci in their organs. The data on the duration of persistence of the infective agent, as well as on the importance of this phenomenon for determination of the relationship between pneumococcal carriership and disease, are presented.

The serotyping of pneumococci isolated from different material obtained from children aged 0 to 11 years was carried out. Out of 156 patients with different diseases, hospitalized in two clinics in Moscow during February-May 1983, pneumococci were isolated from 67 patients (43%). The isolated pneumococcal strains belonged to 11 serotypes. Pneumococci of serotypes 3, 6, 9 and 19 were shown to occur most frequently in different diseases and constituted 50% of the isolated strains. The inoculation of the material by the quantitative method permitted the authors to find out the role of pneumococci as the etiological factor in the pathogenesis of some diseases. A certain dependence of diversity in the types of isolated pneumococci on the age of sick children was noted. Almost all isolated strains were found to be sensitive to penicillin, ampicillin and benzylpenicillin. But a few individual strains were sensitive only to one of these antibiotics. The data on some biological properties of pneumococci cultivated on solid culture media are presented.

A culture medium for the isolation and cultivation of pneumococci, produced in a solid or liquid form and based on raw material unsuitable for use as foodstuff (human placenta), has been developed. The amino acid composition of the medium has been studied. The medium has been found to contain 19 amino acids, to be free from ballast serum proteins and blood, and to ensure the good growth of pneumococci isolated from pathological material, the formation of the normal capsule, as well as active biological properties. The medium has proved to create elective and selective conditions enhancing the effectiveness of investigations and simplifying the isolation of pneumococci in the microbiological examination of patients.

A determination was made of the characteristics of an electric-discharge XeCl laser with x-ray preionization and quasi-cw excitation. An electrical line with ceramic capacitors was used for the first time as a storage device. A specific laser output energy of 3.25 J/liter and an efficiency of approx.1.6% was achieved. Matching of the line and discharge gap impedances was found to be possible at high charging voltages by adding helium to the Ne--Xe--HCl active medium.

Self-control is a personality dimension that is associated with better physical health and a longer lifespan. Here we examined (1) whether self-control is associated with buccal and saliva DNA-methylation (DNAm) measures of biological aging quantified in children, adolescents, and adults, and (2) whether biological aging measured in buccal DNAm is associated with self-reported health. Following preregistered analyses, we computed two DNAm measures of advanced biological age (PhenoAge and GrimAge Acceleration) and a DNAm measure of pace of aging (DunedinPACE) in buccal samples from the German Socioeconomic Panel Study (SOEP-G[ene], n = 1058, age range 0-72, M age = 42.65) and saliva samples from the Texas Twin Project (TTP, n = 1327, age range 8-20, M age = 13.50). We found that lower self-control was associated with advanced biological age in older adults ( β =-.34), but not young adults, adolescents or children. This association was not accounted for by statistical correction for socioeconomic contexts, BMI, or genetic correlates of low self-control. Moreover, a faster pace of aging and advanced biological age measured in buccal DNAm were associated with worse self-reported health ( β =.13 to β = .19). But, effect sizes were weaker than observations in blood, thus customization of DNAm aging measures to buccal and saliva tissues may be necessary. Our findings are consistent with the hypothesis that self-control is associated with health via pathways that accelerate biological aging in older adults.

Children who are socioeconomically disadvantaged are at increased risk for high body mass index (BMI) and multiple diseases in adulthood. The developmental origins of health and disease hypothesis proposes that early life conditions affect later-life health in a manner that is only partially modifiable by later-life experiences. Epigenetic mechanisms may regulate the influence of early life conditions on later life health. Recent epigenetic studies of adult blood samples have identified DNA-methylation sites associated with higher BMI and worse health (epigenetic-BMI). Here, we used longitudinal and twin study designs to examine whether epigenetic predictors of BMI developed in adults are valid biomarkers of child BMI and are sensitive to early life social determinants of health. Salivary epigenetic-BMI was calculated from two samples: (1) N=1,183 8-to-19-year-olds (609 female, mean age=13.4) from the Texas Twin Project (TTP), and (2) N=2,020 children (1,011 female) measured at 9 and 15 years from the Future of Families and Child Well-Being Study (FFCWS). We found that salivary epigenetic-BMI is robustly associated with children's BMI ( r =0.36 to r =0.50). Longitudinal analysis suggested that epigenetic-BMI is highly stable across adolescence, but remains both a leading and lagging indicator of BMI change. Twin analyses showed that epigenetic-BMI captures differences in BMI between monozygotic twins. Moreover, children from more disadvantaged socioeconomic status (SES) and marginalized race/ethnic groups had higher epigenetic-BMI, even when controlling for concurrent BMI, pubertal development, and tobacco exposure. SES at birth relative to concurrent SES best predicted epigenetic-BMI in childhood and adolescence. We show for the first time that epigenetic predictors of BMI calculated from pediatric saliva samples are valid biomarkers of childhood BMI that are sensitive to social inequalities. Our findings are in line with the hypothesis that early life conditions are especially important factors in epigenetic regulation of later life health. Research showing that health later in life is linked to early life conditions have important implications for the development of early-life interventions that could significantly extend healthy life span., Competing Interests: Conflict of Interest Disclosures (includes financial disclosures): The authors have no competing interests to declare.