Oval Zone Research Articles

Bilateral Tubal Pregnancy Complicated by Rupture of the Left Fallopian Tube

Introduction: Bilateral ectopic pregnancy is a very rare condition which occurs in 1/725 - 1/1580 ectopic pregnancies, most commonly after induced assisted reproductive techniques. Aim: To present the case of spontaneous bilateral tubal pregnancy, and the problem of insufficiency of available diagnostic methods, which causes that an accurate diagnosis can mostly be made intraoperatively. Case Report: A 37-year-old female, nulliparous, comes at the Clinic of Gynecology and Obstetrics of CCUS, complains of intense suprapubic pain, and difficulty urinating. The expected menstruation was absent for more than 2 weeks. The Grav index test was positive. Beta hCG values were 6312 IU/L. On examination, the patient was extremely pale, hypotensive, gave the impression of hemorrhagic shock, and the abdomen was diffusely palpably painful. After emergency TV ultrasound, then ultrasound and CT of the abdomen and small pelvis, which indicate a moderate amount of thicker fluid in the abdomen and small pelvis in terms of hemoperitoneum and with the left contour of the uterus an oval zone most likely to correspond to ectopic pregnancy, an indication for emergency surgery was made. A laparotomy was performed, and partly liquid and partly coagulated blood was found in the abdomen. The left tube in the isthmic part was ruptured with active bleeding. Right Fallopian tube was pathologically changed, livid, with visible suspicious pregnancy in the ampullary part. Bilateral salpingectomy was performed, and samples are sent for PHD analysis that shows the presence of chorionic villi in both tubes. Conclusion: When ectopic pregnancy is suspected, the possibility of bilateral tubal pregnancy should always be kept in mind, especially in cases accompanied by acute pelvic pain with signs of hemorrhagic shock

Age-related focal thinning of the ganglion cell-inner plexiform layer in a healthy population.

Given the aging of the population worldwide, to learn the underlying age-related biological phenomena is important to improve the understanding of the ageing process. Neurodegeneration is an age-associated progressive deterioration of the neuron. Retinal neurodegeneration during aging, such as the reduction in thickness of the retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL) measured by optical coherence tomography (OCT), has been reported, but no studies have provided their specific alteration patterns with age. Therefore, this study is to provide visualization of the evolution of various tomographic intraretinal layer thicknesses during aging and to document age-related changes in focal thickness. A total 194 healthy subjects were included in this cross-sectional study. The subjects were divided into four age groups: G1, <35 years; G2, 35-49 years; G3, 50-64 years; and G4 ≥65 years. One eye of each subject was imaged using a custom-built ultrahigh-resolution optical coherence tomography (UHR-OCT). Volumetric data centered on the fovea were segmented to obtain the thickness maps of six intraretinal layers, including the macular retinal nerve fiber layer (mRNFL) and GCIPL. There were alterations visualized in thickness maps in these intraretinal layers. The GCIPL showed a thickness reduction localized in the inner annulus in elder subjects (G4). Within the inner annulus, the most profound alteration in G4, an oval zone (length 0.76 mm and width 0.52 mm), appeared to be in the inferior sector about 0.61 mm below the fovea, named "A zone". The average thickness reduction of the A zone was 14.4 µm in the elderly group (G4). Age was significantly related to the GCIPL thickness of the inner annulus (ρ =-0.48; P<0.001) and of the A zone (ρ =-0.39, P<0.001). This is the first study to apply UHR-OCT for visualizing the age-related alteration of intraretinal layers in a general population. The most profound change of the optic nerve fiber is an oval-like focal thinning in GCIPL, which occurred in the inferior sector within the inner annulus and was strongly related to increased age.

Delineation of site‐specific management zones using estimation of distribution algorithms

AbstractIn this paper, we present a novel methodology to solve the problem of delineating homogeneous site‐specific management zones (SSMZ) in agricultural fields. This problem consists of dividing the field into small regions for which a specific rate of inputs is required. The objective is to minimize the number of management zones, which must be homogeneous according to a specific soil property: physical or chemical. Furthermore, as opposed to oval zones, SSMZ with rectangular shapes are preferable since they are more practical for agricultural technologies. The methodology we propose is based on evolutionary computation, specifically on a class of the estimation of distribution algorithms (EDAs). One of the strongest contributions of this study is the representation used to model the management zones, which generates zones with orthogonal shapes, for example, L or T shapes, and minimizes the number of zones required to delineate the field. The experimental results show that our method is efficient to solve real field and randomly generated instances. The average improvement of our method consists in reducing the number of management zones in the agricultural fields concerning other operations research methods presented in the literature. The improvement depends on the size of the field and the level of homogeneity established for the resulting management zones.

Climatology Characteristics of Ionospheric Irregularities Described with GNSS ROTI

At equatorial and high latitudes, the intense ionospheric irregularities and plasma density gradients can seriously affect the performances of radio communication and satellite-based navigation systems; that represents a challenging topic for the scientific and engineering communities and operational use of communication and navigation services. The GNSS-based ROTI (rate of TEC index) is one of the most widely used indices to monitor the occurrence and intensity of ionospheric irregularities. In this paper, we examined the long-term performance of the ROTI in terms of finding the climatological characteristics of TEC fluctuations. We considered the different scale temporal signatures and checked the general sensitivity to the solar and geomagnetic activity. We retrieved and analyzed long-term time-series of ROTI values for two chains of GNSS stations located in European and North-American regions. This analysis covers three full years of the 24th solar cycle, which represent different levels of solar activity and include periods of intense geomagnetic storms. The ionospheric irregularities’ geographical distribution, as derived from ROTI, shows a reasonable consistency to be found within the poleward/equatorward boundaries of the auroral oval specified by empirical models. During magnetic midnight and quiet-time conditions, the equatorward boundary of the ROTI-derived ionospheric irregularity zone was observed at 65–70° of north magnetic latitude, while for local noon conditions this boundary was more poleward at 75–85 magnetic latitude. The ionospheric irregularities of low-to-moderate intensity were found to occur within the auroral oval at all levels of geomagnetic activity and seasons. At moderate and high levels of solar activity, the intensities of ionospheric irregularities are larger during local winter conditions than for the local summer and polar day conditions. We found that ROTI displays a selective latitudinal sensitivity to the auroral electrojet activity—the strongest dependence (correlation R &gt; 0.6–0.8) was observed within a narrow latitudinal range of 55–70°N magnetic latitude, which corresponded to a band of the largest ROTI values within the auroral oval zone expanded equatorward during geomagnetic disturbances.

A new ammonite faunal horizon in the Ovale Zone (Middle Jurassic, Lower Bajocian) and observations on the ammonite genus Sonninia at Coombe Quarry, Mapperton, near Beaminster, Dorset

Biostratigraphy is presented for horizons in the Discites to Sauzei zones at Coombe Quarry and Top Field at Mapperton, Dorset. The significance of these horizons is highlighted. Part of a chronocline is described in the Sonniniidae of the Discites Zone. A new ammonite faunal horizon, Docidoceras higginsi sp. nov. is erected as the oldest of the Ovale Zone. A revised subdivision of the zone is presented and the implications for the taxonomy and biogeography of the Stephanoceratidae is discussed. The distribution of Docidoceras may imply entry to western Tethys via a Hispanic Corridor. A method is presented for the allocation of generic names constituting segments of lineages.

Sequential delivery of long-pulsed 755-nm alexandrite laser and long-pulsed 1,064-nm neodymium:yttrium-aluminum-garnet laser treatment for pigmented disorders.

Long-pulsed (LP) lasers at pulse durations of 1-300ms have been used to destroy nests of nevi cells by selectively targeting pigment chromophores. To evaluate dual-wavelength LP laser-induced tissue reactions. The patterns of LP 755-nm alexandrite (Alex) and/or 1064-nm neodymium (Nd):yttrium-aluminum-garnet (YAG) laser-induced tissue reactions were macroscopically evaluated using a tattoo-embedded phantom. Additionally, a pilot in vivo human study was performed for common acquired melanocytic nevus, of which dermoscopic images and high-speed cinematographs were obtained. Combinations of Nd:YAG and Alex laser treatments at interpulse intervals of 10 or 20ms generated round to oval zones of photothermal and photoacoustic injury in two distinctive areas containing disintegrated tattoo particles. Treatment at interpulse intervals of 10 or 20ms between Alex and Nd:YAG pulses elicited lesser degrees of thermal damage to surrounding tissues, compared to treatment at 100 or 200ms. Immediately after combined LP laser treatment of human nevus lesions in vivo, Nd:YAG-Alex treatment at a 20-ms interpulse interval exhibited more remarkable crusting and erosive appearances than Alex-Nd:YAG treatment. For treating pigmented disorders, sequential delivery of LP Nd:YAG and Alex pulses at short interpulse intervals of 10-20ms can effectively destroy nests of pigment chromophores.

THE DEPENDENCE ON THE GEOMAGNETIC ACTIVITY OF CHANGES IN THE foF2 VALUES AT THE HIGH LATITUDES

In this study, changes according to invariant magnetic latitude of the hourly foF2 data that are taken from seven ionosondes stations are situated at between 60 o -90 o invariant magnetic latitude as known high latitude region are investigated for different geomagnetic activity conditions during December 1971-September 1972. According to the results obtained from the analyzes, it was found that the foF2 values in the daytime are larger than those in the nighttime, and the foF2 values in these hours decreases with the increasing of the invariant magnetic latitude the except for between about 68 o and 72 o invariant magnetic latitude. At night time, it was observed that the foF2 values increases between about 66 o and 72 o invariant magnetic latitude, while the foF2 values exhibit a trough structure at larger and smaller latitudes than these latitudes. It is also observed that seasonal and geomagnetic activity changes have a significant influence on the latitudinal changes of the foF2 values. The foF2 values in the geomagnetic quiet condition are larger than the foF2 values in the geomagnetic active conduction. Especially in the geomagnetic active conduction of the December, the polar cap and polar oval zones are more prominent and have a larger latitudinal structure.

Latitude Dependence of Low‐Altitude O+ Ion Upflow: Statistical Results From FAST Observations

AbstractWe introduce a statistical model to explain the latitudinal dependence of the occurrence rate and energy flux of the ionospheric escaping ions, taking advantage of advances in the spatial coverage and accuracy of FAST observations. We use a weighted piecewise Gaussian function to fit the dependence, because two probability peaks are located in the dayside polar cusp source region and the nightside auroral oval zone source region. The statistical results show that (1) the Gaussian Mixture Model suitably describes the dayside polar cusp upflows, and the dayside and the nightside auroral oval zone upflows. (2) The magnetic latitudes of the ionospheric upflow source regions expand toward the magnetic equator as Kp increases, from 81° magnetic latitude (MLAT) (cusp upflows) and 63° MLAT (auroral oval upflows) during quiet times to 76° MLAT and 61° MLAT, respectively. (3) The dayside polar cusp region provides only 3–5% O+ upflows among all the source regions, which include the dayside auroral oval zone, dayside polar cusp, nightside auroral oval zone, and even the polar cap. However, observations show that more than 70% of upflows occur in the auroral oval zone and that the occurrence probability increases at the altitudes of 3500–4200 km, which is considered to be the lower altitude boundary of ion beams. This observed result suggests that soft electron precipitation and transverse wave heating are the most efficient ion energization/acceleration mechanisms at the altitudes of FAST orbit, and that the parallel acceleration caused by field‐aligned potential drops becomes effective above that altitude.

Geomagnetic and solar activity dependence of ionospheric upflowing O+: FAST observations

This paper investigates the dependence of the occurrence frequency of ionospheric upflowing oxygen (O+) ions on the sunspot cycle and geomagnetic activity. We examine the upflows response to the geomagnetic disturbances as well as the influence of the ion energy factor in controlling the magnitude of the occurrence frequency and the net energy flux. We discuss the spatial distribution of the upflow occurrence frequency and construct a regression model as a function of the magnetic latitude. The results show an overall enhancement of the upflow occurrence frequency during magnetically disturbed periods and indicate that the high-occurrence area spreads out from the source regions during magnetically quiet periods. The high-occurrence areas are located at 70° magnetic latitude (mLat) in the dayside auroral oval zone and between 76–80° mLat in the dayside polar cusp region. In the nightside auroral oval zone, these areas are near 60° mLat, penetrating further equatorward to 55° mLat during magnetically disturbed periods. High energy (≥1 keV) upflowing ions are common in the nightside auroral oval zone while low energy (<1 keV) upflowing ions are found escaping from the high latitude dayside cusp region. A Gaussian function is shown to be a good fit to the occurrence frequency over the magnetic latitude. For high energy upflowing O+ ions, the occurrence frequency exhibits a single peak located at about 60° mLat in the nightside auroral oval zone while for low energy upflowing O+ ions, it exhibits two peaks, one near 60° mLat in the auroral oval zone and the other near 78° mLat in the cusp region. We study the solar activity dependence by analyzing the relationship between the upflow occurrence frequency and the sunspot number (\(R_{Z}\)). The statistical result shows that the frequency decreases with declining solar activity level, from ∼30 % at solar maximum to ∼5 % at solar minimum. In addition, the correlation coefficient between the occurrence frequency and \(R_{Z}\) is 0.9.

Transcutaneous pneumatic injection of glucose solution: a morphometric evaluation of in vivo micropig skin and tissue-mimicking phantom.

Needle-free, transcutaneous pneumatic injection systems can be used to deliver therapeutic solutions to targeted layers of skin in a minimally invasive manner. To evaluate jet infiltration patterns and tissue reactions, 5% isotonic and 20% hypertonic glucose solutions were pneumatically injected into in vivo micropig skin. Gelatin TM phantom was additionally prepared to analyze penetration and dispersion patterns for different experimental settings. As immediate tissue reactions in the in vivo micropig skin, distinct pneumatic injection injury zones (PIIZs) in the dermis, extending from the papillary dermis deep into the dermo-subcutaneous junction, were generated with the 5% and 20% glucose solutions and with pneumatic pressures of 4.64 and 5.7 bars, respectively. PIIZs markedly decreased in appearance at 1 day after treatment, accompanied by inflammatory cell infiltration, and disappeared at 7 days post-treatment with increased collagen and elastin production. In TM phantom study, the PIIZs created by 20% glucose mainly comprised a single, homogenous, round to oval zone, whereas those created by 5% glucose were irregular and multi-lobular. The present study suggests that transcutaneous pneumatic injection therapy may exert mechanical stimulatory effects, immediate tissue shrinkage via hypertonic solutions, and late tissue regeneration effects during wound healing.

Labyrinthoceras and Frogdenites (Sphaeroceratidae, Ammonitina) from Western Tethys: The origin of the Sphaeroceratidae

A biostratigraphical and systematic revision of the genera Labyrinthoceras and Frogdenites is presented, based mostly on new specimens from the Lower Bajocian of the Betic Cordillera (Southern Spain). Types and other supporting specimens are described, including some from southwestern England with precise biostratigraphy. Frogdenites is shown to span the Lower Bajocian (Ovale Zone to lowermost part of the Propinquans Zone), whereas Labyrinthoceras ranges from the Laeviuscula Zone (Trigonalis Subzone) to the Propinquans Zone. Both genera show well-marked dimorphism; the microconchs may have reduced lateral lappets. Labyrinthoceras meniscum (Waagen) [M] & [m] = Manselites mansellii (J. Buckman) is described along with specimens that are placed in the new species Labyrinthoceras dietzei nov. sp. [M]. Frogdenites is grouped into three morphospecies: Frogdenites fernandezlopezi nov. sp. [M] & [m?], an evolute morph with poorly developed tubercles; F. spiniger Buckman [M] & [m], which is more involute with strongly forward curving projecting ribs; and F. extensus (Buckman) [M] & [m] with a more eccentric coiling. Docidoceras tolleyi nov. sp., which possesses a morphology intermediate between Docidoceras and Frogdenites, is described. Phylogenetic analysis shows that the Sphaeroceratidae originated in the Earliest Bajocian (Ovale Zone) and that Frogdenites is the oldest genus of this lineage. Docidoceras rather than Emileia may be the ancestor of the Sphaeroceratidae. The evolutionary path from Frogdenites to Labyrinthoceras, with “Chondroceras obornensis” Parsons, 1980 (unpubl. manuscript), as an intermediate step, involves size increase and disappearance of tubercles.

Dimorphism and evolution of Albarracinites (Ammonoidea, Lower Bajocian) from the Iberian Range (Spain)

Several tens of specimens of Lower Bajocian Albarracinites (type species A. albarraciniensis Fernandez-Lopez, 1985), including microconchs and macroconchs from the Iberian Range, have been studied. This ammonite genus ranges in the Iberian Range from at least the Ovale Zone to the uppermost Laeviuscula Zone of the Lower Bajocian (Middle Jurassic). The macroconch counterpart is thought to be a group of stephanoceratids previously attributed to Mollistephanus, Riccardiceras and other new forms described in this paper. Two chronologically successive species of Albarracinites have been identified: A. albarraciniensis and A. submediterraneus sp. nov. The evolution of the Albarracinites lineage represents a hypermorphic peramorphocline starting from depressed, small and slender serpenticones of A. westermanni, to larger planorbicones with more cadiconic phragmocones and body chamber of subcircular cross section belonging to A. submediterraneus sp. nov., through A. albarraciniensis Fernandez-Lopez. In contrast, Mollistephanus planulatus (Buckman), M. cockroadensis Chandler & Dietze and M. mollis Buckman represent a peramorphocline by acceleration, producing adults of similar size but more compressed and with increasing ontogenic variation of shell ornament. Albarracinites and Mollistephanus subsequently developed two opposite peramorphoclines or gradational series of morphological changes undergoing greater development and ontogenic variation. These two genera show diverse palaeobiogeographical distributions too. Albarracinites is rarely recorded in the Mediterranean and Submediterranean from the Discites to the Laeviuscula Zone, whereas Mollistephanus is more common in north-western Europe and other biochoremas of the western Tethys from the Discites Zone to the Sauzei Zone. Albarracinites seems to be the earliest stephanoceratid lineage in western Tethys, branching off from the otoitid Riccardiceras by proterogenetic change and resulting in paedomorphosis at the Aalenian/Bajocian boundary.http://zoobank.org/urn:lsid:zoobank.org:pub:09B95E3C-00E7-4A9E-907B-656255AA7B00

Extremely strong geomagnetic storm of September 2–3, 1859, according to the archived data of observations at the Russian network

A retrospective analysis of the Russian magnetic observations of the Carrington event that occurred on September 2–3, 1859, has been performed. The conclusion has been made that this event was caused by the series of three recurrent eruptive solar flares during ∼40 h. The characteristics of the geomagnetic crochet, related to a considerable flux of the ionizing electromagnetic radiation during this flare, have been studied. The value and direction of a magnetic field disturbance, registered during the maximum of the geomagnetic storm of September 2, unambiguously indicate that all Russian stations were in the auroral oval zone, which was strongly expanded southward from its average position. The disturbance dependence on the station longitude—the absence of magnetometer pinning in Nerchinsk—is interpreted as the possible manifestation of a strong asymmetry in the effective contour of the current system, which was connected to the heliosphere and covered the disturbed magnetosphere and ionosphere during the short period that lasted only 1–3 h.

Control of the spatial dynamics of the polar cap and auroral oval based on data from the Greenland network of magnetic stations

The technique for determining the spatial location of the polar cap, auroral oval, and subauroral zone of the high-latitude space, based on the geomagnetic data from the Greenland chain of magnetic stations, is proposed. The belonging of a specific station to one of the zones is determined based on the results of operation of a self-learning classification artificial neural network of a Kohonen-layer type. The amplitude-frequency spectra and the matrices of wavelet coefficients for analyzing data from the magnetic observation network are the input calculation parameters.

Possible consequences of the displacement of Magnetic Poles on the structure and dynamics of the earth’s upper atmosphere

1. The velocity and acceleration of the North Magnetic Pole (NMP) motion has been increasing sharply since the 1970s and has almost doubled (up to 46 km/yr) in the last 30 yr [1]. During the same period, the velocity of the South Magnetic Pole (SMP) displacement decreased, and its motion has practically stopped since 1986. Wandering in the territory of North Canada gave way to stable, almost rectilinear motion of the Russian Arctic sector with linearly increasing acceleration. Given that the present-day trend continues, extrapolation of the NMP coordinates makes it possible to forecast that the NMP will be located in the Severnaya Zemlya Archipelago region by 2050. Such displacement of the NMP can provoke several physical consequences in the earth’s atmosphere and ionosphere. 2. It is known that the existing structure of the earth’s ionosphere and thermosphere reflects the dynamic balance between the energy influx with solar radiation depending on the geophysical coordinates and energy input from the magnetosphere with the fluxes of energetic charged particles in the auroral oval zone [2], which depends on the geomagnetic coordinates of the site. The displacement of magnetic poles would influence the following physical processes: (1) the balance of the solar and corpuscular ionization would change; (2) intense increase of ionization in the E layer at midlatitudes in the auroral zone would directly influence the radiowave propagation; (3) new spatial structure of plasma convection would change the formation and location of the main ionospheric depression; (4) the maximum of Joule heat intensity would displace to mid-latitudes that would influence the distribution of neutral atmosphere parameters, such as temperature, [O]/[N 2 ] ratio, and vertical wind velocity; and (5) the system of neutral winds and ionospheric response to magnetic storms would change. Judging from the forecasted location of the NMP,

The dynamics of the auroral oval and ionospheric trough boundaries according to data from the DMSP satellites and ground-based ionosonde network

This paper presents the results of a combined analysis of the experimental data of vertical- and oblique-incidence ionospheric sounding in the northeastern region of Russia and of the DMSP satellite data from 1999 to 2003. During geomagnetic disturbances period on ionograms we can see anomalous diffuse signals, which propagates outside great circle arc. The joint data analysis permits to suggest that the appearance of additional anomalous signals is connected with radio waves refraction in auroral oval and main ionospheric trough areas and with scattering on small-scale field-aligned irregularities close to auroral oval equatorial boundary in the region of electron diffuse precipitation. The basic attention is given to diagnostics of main ionospheric trough boundary and auroral oval zones position during geomagnetic disturbances periods.

New data on the Lower Bajocian (Middle Jurassic) ammonite genus Mollistephanus Buckman, 1922 from southern England

The dimorphic ammonite genus Mollistephanus Buckman, 1922 (type species: Mollistephanus mollis Buckman, 1922 [M]) is shown to range in southern England from the Discites to the Sauzei Zones of the Lower Bajocian (Middle Jurassic). The microconch counterpart is thought to be Albarracinites Fernandez-Lopez, 1985, previously described from Spain. The earliest species is taken to be ‘Docidoceras’ planulatum Buckman from the Discites Zone of Dorset. Similar but distinct forms of Mollistephanus in the succeeding Ovale Zone are named M. cockroadensis sp. nov. [M], The acme of the genus lies in the Trigonalis Subzone of the Laeviuscula Zone, the type horizon of its type species M. mollis in ammonite faunal horizon Bj-8b of the current biozonal classification. It is accompanied there by rare Albarracinites albarraciniensis Fernandez-Lopez [m]. Younger transients of Mollistephanus range upwards in the Laeviuscula Subzone, Bj-10, and into the lower Sauzei Zone, Bj-1 la. The assemblage from each horizon is monobiospecific. The origins of the genus and its relations to the parallel phyletic mainstem of the Stephanoceatidae, Stephanoceras s. l. , including another dwarf genus Phaulostephanus in the overlying Humphriesianum Zone, are discussed but remain unresolved.

Shock aurora: FAST and DMSP observations

Global signatures of the aurora caused by interplanetary shocks/pressure pulses have been studied in recent years using ultraviolet imager data from polar orbiting spacecraft. The signatures include the occurrence of the aurora first near local noon and then propagation antisunward along the auroral oval at very high speeds. To better understand the mechanisms of particle precipitation, in this paper we study shock auroras using near‐Earth observations of the FAST and DMSP satellites. We have studied the events that occurred during 1996–2000 where FAST and/or DMSP crossed the dawnside or duskside auroral zone within 10 min after shocks/pressure pulses arrived at the nose of the magnetopause. It is found that the electron precipitation increased significantly above the dawnside and duskside auroral oval zone after the shock/pressure pulse arrivals. The precipitation structure is low‐energy electrons (&lt;∼1 keV) at higher latitudes (∼75°–83° ILAT within 0600–0900 MLT) and high‐energy electrons (∼1–10 keV) at lower latitudes (∼65°–79° ILAT) of the auroral zone. There are a few degrees (1°–4° ILAT) of overlap between these two categories of precipitated electrons. The precipitation of low‐energy electrons was along highly structured field‐aligned currents. The precipitation of the high‐energy electrons was highly isotropic filling the loss cone. Possible mechanisms of field‐aligned current generation are some dynamic processes occurring on the dayside magnetopause, such as magnetic shearing, magnetopause perturbation, magnetic reconnection, and Alfvén wave generation. Adiabatic compression might have caused the high‐energy electron precipitation. On the basis of observations of FAST and DMSP, shock auroras are speculated to be diffuse auroras at the lower latitudes of the dayside auroral oval and discrete auroras on the poleward boundary of the oval with a few latitude degree overlap of the two types of auroras.

X-ray imaging techniques and exobiology

X-ray imaging techniques at the best spatial resolution and using synchrotron facilities are put forth as powerful techniques for the search of small life forms in extraterrestrial rocks under quarantine conditions. Absorption and fluorescence X-ray microtomographies on sub-millimeter silicate assemblages inside a container reveal the mineralogical microenvironments were life should be looked for in priority. Limitations with respect to bacterial detection are due to the difficulties to obtain information about light elements (Z less than or equal to 14), major constituents of biological and silicate samples. The X-ray signature of a present bacteria on a silicate surface was defined by X-ray mapping, out of a container, as coincident micrometer and oval zones having strong P and S fluorescence lines (S-fluorescence being slightly lower than P-fluorescence) and an amino-linked sulfur redox speciation. The detection of a single cell along with new procedures to calculate tomographic views will allow considerable improvements of 3D detection of life by X-ray techniques.

NGC 3081: Surface Photometry and Kinematics of a Classic Resonance Ring Barred Galaxy

This paper presents a detailed photometric and kinematic study of the well-known Seyfert 2 galaxy NGC 3081, one of the best examples of a resonance ring barred galaxy in the sky. Improved optical images compared to previous studies reveal that NGC 3081 is a classic R1R galaxy, a type that shows a distinctive outer ring/pseudoring pattern at large radii that can be linked to orbit families at the outer Lindblad resonance (OLR). Together with an exceptionally strong inner ring and a blue nuclear ring, NGC 3081 has the rare distinction of having all four of the main types of resonance rings that have been predicted by test-particle models of barred spirals. Near-infrared imaging of NGC 3081 reveals clear old rings connected to the inner ring and the R1 outer ring. Objective comparison of the B- and H-band positions of the inner ring indicates no significant difference in shape, major-axis position angle, or major-axis radius between the two passbands, in spite of the different stellar populations each band emphasizes. Imaging Fabry-Perot interferometry provides an intriguing picture of star formation in the galaxy and of the dynamics of the system. Hα emission is strong in the inner ring and is confined to a bounded elliptical annulus of diffuse emission whose ellipticity increases from the inner edge to the outer edge. A few H II regions are connected to the strong R1-type outer ring, particularly just off the major axis of the inner ring where dimples, typical of the R1 morphology, are found. There is bright emission in an oval zone in the inner 10'' radius, but no enhancement of emission is associated with the blue-light nuclear ring. Since most of the emission is connected with the intrinsically oval inner ring and the bright center, the global dynamics of the galaxy are uncertain. Nevertheless, using a combination of the gravitational potential derived from the H-band light distribution and a simple halo model, we estimate the pattern speed and the location of all major resonances in the disk of NGC 3081. We find that NGC 3081 fits extremely well into recent ideas of barred galaxy dynamics.