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Cool gas (T$\sim$10$^{4}$~K) traced by hydrogen Ly$\alpha$ emission is now routinely detected around $z\sim3$ quasars, but little is known about their molecular gas reservoirs. Here, we present an APEX spectroscopic survey of the CO(6-5), CO(7-6) and [CI](2-1) emission lines for 9 quasars from the QSO MUSEUM survey which have similar UV luminosities, but very diverse Ly$\alpha$ nebulae. These observations ($\langle~\rm rms~\rangle=2.6$~mJy in 300~km~s$^{-1}$) detected three CO(6-5) lines with 3.4$\leq I_{\rm CO(6-5)} \leq$5.1~Jy~km~s$^{-1}$, 620$\leq$FWHM$\leq$707~km~s$^{-1}$, and three [CI](2-1) lines with 2.3$\leq I_{\rm [CI](2-1)} \leq$15.7~Jy~km~s$^{-1}$, 329$\leq$FWHM$\leq$943~km~s$^{-1}$. For the CO and [CI] detected sources, we constrain the molecular gas reservoirs to be $\rm M_{H_{2}} = (0.4-6.9) \times 10^{11} M_{\odot}$, while the non-detections imply $\rm M_{H_{2}} < 1.1\times 10^{11} M_{\odot}$. We compare our observations with the extended Ly$\alpha$ properties to understand the link between the cool and the molecular gas phases. We find large velocity shifts between the bulk of Ly$\alpha$ and the molecular gas systemic redshift in five sources (from $\sim$-400 to $\sim+$1200~km~s$^{-1}$). The sources with the largest shifts have the largest Ly$\alpha$ line widths in the sample, suggesting more turbulent gas conditions and/or large-scale inflows/outflows around these quasars. We also find that the brightest ($I_{\rm[CI](2-1)}=15.7\pm3.7~\rm Jy~km~s^{-1}$) and the widest (FWHM$\sim$900~km~s$^{-1}$) lines are detected for the smallest and dimmest Ly$\alpha$ nebulae. From this, we speculate that host galaxy obscuration can play an important role in reducing the ionizing and Ly$\alpha$ photons able to escape to halo scales, and/or that these systems are hosted by more massive halos., Comment: Accepted on January 3, MNRAS. 25 pages, 17 figures

We have conducted a study of extra-planar diffuse ionized gas using the first year data from the MaNGA IFU survey. We have stacked spectra from 49 edge-on, late-type galaxies as a function of distance from the midplane of the galaxy. With this technique we can detect the bright emission lines Halpha, Hbeta, [OII]3726, 3729, [OIII]5007, [NII]6549, 6584, and [SII]6717, 6731 out to about 4 kpc above the midplane. With 16 galaxies we can extend this analysis out to about 9 kpc, i.e. a distance of ~2R_e, vertically from the midplane. In the halo, the surface brightnesses of the [OII] and Halpha emission lines are comparable, unlike in the disk where Halpha dominates. When we split the sample by specific star formation rate, concentration index, and stellar mass, each subsample's emission line surface brightness profiles and ratios differ, indicating that extra-planar gas properties can vary. The emission line surface brightnesses of the gas around high specific star formation rate galaxies are higher at all distances, and the line ratios are closer to ratios characteristic of HII regions compared with low specific star formation rate galaxies. The less concentrated and lower stellar mass samples exhibit line ratios that are more like HII regions at larger distances than their more concentrated and higher stellar mass counterparts. The largest difference between different subsamples occurs when the galaxies are split by stellar mass. We additionally infer that gas far from the midplane in more massive galaxies has the highest temperatures and steepest radial temperature gradients based on their [NII]/Halpha and [OII]/Halpha ratios between the disk and the halo., Comment: 19 pages, 14 figures, 2 appendices. Accepted in A&A (see https://drive.google.com/open?id=0B_MhxrO1dvVNUUUtb0FXdllqb0E for full version)

We have used the European VLBI Network (EVN) to observe a sample of Lyman Break Analogs (LBAs), nearby (z < 0.3) galaxies with properties similar to the more distant Lyman Break Galaxies (LBGs). The study of LBGs may help define the feed-back relationship between black holes (BHs) and their host galaxies. Previous VLA observations have shown that the kpc-scale radio emission from LBAs is dominated by starbursts. The main targets of this VLBI experiment were selected because they possessed emission-line properties between starbursts and Type 2 (obscured) AGN. Eight targets (three star-forming LBAs, four composite LBAs, and one Type 1 AGN) were observed at 5 GHz, four of which were also observed at 1.7 GHz. One star-forming LBA and one composite LBA were detected above 5 \sigma at 1.7 GHz (only), while the AGN was detected at 5 GHz. In both LBAs, the radio luminosity (LR) exceeds that expected from supernovae (remnants) based on a comparison with Arp220, Arp229A and Mrk273, by factors of 2 - 8. The composite LBA exhibits a compact core emitting around 10% of the VLA flux density. The high Tb of 3.5E7 K and excess core L_R with respect to the L_R/L_X relation of radio-quiet AGN indicate that this LBA possesses an obscured AGN (MBH ~ E5-E7 M_sun). While weak AGN may co-exist with the starbursts as shown in at least one of the LBAs, their contribution to the total radio flux is fairly minimal. Our results show that the detection of such weak AGN presents a challenge at radio, X-ray and optical emission-line wavelengths at z ~ 0.2, indicating the great difficulties that need to be overcome in order to study similar processes at high redshift when these types of galaxies were common.

We present the results of the analysis of a sample of 17 low-luminosity (LX . 10 42 erg/s), radio loud AGNs in massive galaxies. The sample is extracted from the SDSS database and it spans uniformly a wide range in optical [OIII] emission line and radio luminosity, but within a narrow redshift range (0.05 < z < 0.11) and a narrow super massive black hole mass range (� 10 8 M⊙). For these sources we measured core X-ray emission with the Chandra X-ray telescope and radio emission with the VLA. Our main goal is to establish which emission component, if any, can be regarded as the most reliable accretion/jet-power estimator at these regimes. In order to do so, we studied the correlation between emission line properties, radio luminosity, radio spectral slopes and X-ray luminosity, as well as more complex multi-variate relations involving black hole mass, such as the fundamental plane of black hole activity. We find that 15 out of 17 sources of our sample can be classified as Low-Excitation Galaxies (LEG) and their observed properties suggest X-ray and radio emission to originate from the jet basis. We also find that X-ray emission does not appear to be affected by nuclear obscuration and can be used as a reliable jet-power estimator. More generally, X-ray, radio and optical emission appear to be related, although no tight correlation is found. In accordance with a number of recent studies of this class of objects these findings may be explained by a lack of cold (molecular) gaseous structures in the innermost region of these massive galaxies.

We present a detailed study of the Galaxy Evolution Explorer's photometric catalogs with special focus on the statistical properties of the All-sky and Medium Imaging Surveys. We introduce the concept of primaries to resolve the issue of multiple detections and follow a geometric approach to define clean catalogs with well-understood selection functions. We cross-identify the GALEX sources (GR2+3) with Sloan Digital Sky Survey (DR6) observations, which indirectly provides an invaluable insight about the astrometric model of the UV sources and allows us to revise the band merging strategy. We derive the formal description of the GALEX footprints as well as their intersections with the SDSS coverage along with analytic calculations of their areal coverage. The crossmatch catalogs are made available for the public. We conclude by illustrating the implementation of typical selection criteria in SQL for catalog subsets geared toward statistical analyses, e.g., correlation and luminosity function studies., Comment: 12 pages, 15 figures, accepted to ApJ

We describe the scientific motivations, the mission concept and the instrumentation of SPACE, a class-M mission proposed for concept study at the first call of the ESA Cosmic-Vision 2015-2025 planning cycle. SPACE aims to produce the largest three-dimensional evolutionary map of the Universe over the past 10 billion years by taking near-IR spectra and measuring redshifts for more than half a billion galaxies at 0, Comment: 27 pages, Experimental Astronomy, in press. The SPACE team complete list is available at http://urania.bo.astro.it/cimatti/space . The article with full resolution figures is available at http://urania.bo.astro.it/cimatti/space/publications.htm

The prevalence of radio-loud AGN activity in present-day massive halos is determined using a sample of 625 nearby groups and clusters selected from the Sloan Digital Sky Survey. Brightest group and cluster galaxies (BCGs) are more likely to host a radio– loud AGN than other galaxies of the same stellar mass (by below a factor of two at a stellar mass of » 5 × 10 11 M¯, but rising to over an order of magnitude below 10 11 M¯). The distribution of radio luminosities for BCGs does not depend on mass, however, and is similar to that of field galaxies of the same stellar mass. Neither the radio–loud fraction nor the radio luminosity distribution of BCGs depends strongly on the velocity dispersion of the host cluster. The radio-AGN fraction is also studied as a function of distance from the cluster centre. Only within 0.2 r200 do cluster galaxies exhibit an enhanced likelihood of radio–loud AGN activity, which approaches that of the BCGs. In contrast to the radio properties, the fraction of galaxies with optical emission–line AGN activity is suppressed within r200 in groups and clusters, decreasing monotonically towards the cluster centre. It is argued that the radio–loud AGN properties of both BCGs and non-BCGs can naturally be explained if this activity is fuelled by cooling from hot gas surrounding the galaxy. Using observational estimates of the mechanical output of the radio jets, the time–averaged energy output associated with recurrent radio source activity is estimated for all group/cluster galaxies. Within the cooling radius of the cluster, the radio–mode heating associated with the BCG dominates over that of all other galaxies combined. The scaling between total radio–AGN energy output and cluster velocity dispersion is observed to be considerably shallower than the » ¾ 4 v scaling of the radiative cooling rate. Thus, unless either the mechanical–to–radio luminosity ratio or the efficiency of converting AGN mechanical energy into heating increases by 2–3 orders of magnitude between groups and rich clusters, radio–mode heating will not balance radiative cooling in systems of all masses. In groups, radio–AGN heating probably overcompensates the radiative cooling losses, and this may account for the observed entropy floor in these systems. In the most massive clusters, an additional heating process (most likely thermal conduction) may be required to supplement the AGN heating.

We discuss the colors of 99,088 galaxies selected from the Sloan Digital Sky Survey Data Release 1 "main" spectroscopic sample (a flux limited sample, rPet < 17.77, for 1360 deg 2 ) in the rest-frame Stromgren system (uz, vz, bz, yz). This narrow-band (�200 u photometric system, first designed for the determination of effective tem- perature, metallicity and gravity of stars, measures the continuum spectral slope of galaxies in the rest-frame 3200-5800 u wavelength range. We synthesize rest-frame Stromgren magnitudes from SDSS spectra, and find that galaxies form a remarkably narrow locus (�0.03 mag) in the resulting color-color diagram. Using the Bruzual & Charlot population synthesis models, we demonstrate that the position of a galaxy along this locus is controlled by metallicity and age of the dominant stellar popula- tion. The distribution of galaxies along the locus is bimodal, with the local minimum corresponding to an �1 Gyr old single stellar population. The position of a galaxy per- pendicular to the locus is independent of metallicity and age, and reflects the galaxy's dust content, as implied by both the models and the statistics of IRAS detections. Comparison of the galaxy locus in the rest-frame Stromgren color-color diagram with the galaxy locus in the H�-Dn(4000) diagram, utilized by Kauffmann et al. (2003) to estimate stellar masses, reveals a tight correlation, although the two analyzed spectral ranges barely overlap. Furthermore, the rest-frame r i color (5500-8500 u wavelength range) can be "predicted" with an rms of 0.05 mag using the rest-frame Stromgren colors. Overall, the galaxy spectral energy distribution in the entire UV to near-IR range can be described as a single-parameter family with an accuracy of 0.1 mag, or better. This nearly one-dimensional distribution of galaxies in the multi- dimensional space of measured parameters strongly supports the conclusion of Yip et al. (2004), based on a principal component analysis, that SDSS galaxy spectra can be described by a small number of eigenspectra. Furthermore, the rest-frame Stromgren colors correlate tightly with the classification scheme proposed by Yip et al. (2004) based on the first three eigenspectra. Apparently, the contributions of stellar popula- tions that dominate the optical emission from galaxies are combined in a simple and well-defined way. We also find a remarkably tight correlation between the rest-frame Stromgren colors of emission-line galaxies and their position in the Baldwin-Phillips- Terlevich diagram. These correlations between colors and various spectroscopic diag- nostic parameters support earlier suggestions that rest-frame Stromgren photometry offers an efficient tool to study faint cluster galaxies and lowsurface brightness objects without performing time-consuming spectral observations.

We interpret galaxy counts in the B and K bands, and the redshift distribution of faint galaxies, using a model for galaxy formation in a hierarchical universe. We first study how variation of each of the free parameters in our model affects its observational predictions. These parameters control processes such as star formation, supernova feedback and merging, and determine the masses and luminosities of the galaxies that populate the evolving distribution of dark matter haloes. We find that more efficient merging results in a galaxy luminosity function with a lower amplitude at the faint end at all epochs. This causes the slope of the faint counts to decrease, and the redshift distribution to shift to higher values of z

Visual ability and compensatory eye movements during defined vertical oscillation were investigated in 20 patients with unilateral lesions of labyrinthine function and in 20 normal subjects. Oscillation frequencies were performed at the rate of 1 to 1.5 Hz with an amplitude of 5 cm, comparative to head locomotions of a running person. In synchronism with this, the visual function was tested with Landolt rings. Patients complaining of subjective visual disturbance during walking and running, also presented a measurable blur of vision under test conditions. In addition, eye movements were recorded and classified into three types. However, these eye movements showed no relation to gaze function. Our results suggest that the otolith-ocular reflex may participate in adjusting the vertical eye position during vertical stimulations at low frequencies. The effect of visual disturbances in patients with labyrinthine lesions is explained by the "efference-copy" initially described by von Holst. The efference-copy is responsible for the neutralisation of provoked retinal perceptions.

Modern imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI) allow high-resolution imaging of the abdomen. Modern scanners made high temporal as well as high spatial resolution available. Therapeutic approaches to the treatment of renal cell carcinoma have been improved over the recent years. Besides conventional and open laparoscopic tumor nephrectomy and nephron sparing, surgical approaches such as local tumor cryotherapy and radiofrequency ablation (RF) are ablative modalities and are used increasingly. Improved anesthesiological methods and new surgical approaches also allow curative treatment in extended tumors. Prerequisites for preoperative imaging modalities include visualization of the kidney tumor as well as its staging. Tumor-related infiltration of the renal pelvis or invasion of the perinephric fat and the renal hilus has to be excluded prior to nephron sparing surgery. In cases with extended tumors with infiltration of the inferior vena cava, it is necessary to visualize the exact extension of the tumor growth towards the right atrium in the vena cava. The radiologist should be informed about the diagnostic possibilities and limitations of the imaging modalities of CT and MRI in order to support the urologist in the planning and performance of surgical therapeutical approaches.

The past decade has witnessed the establishment of a “standard paradigm” for structure formation in the Universe. It is now universally accepted that the dominant matter component of the Universe is in some form of non-baryonic, weaklyinteracting dark matter. Structure in the dark matter originated from inhomogeneities that were generated shortly after the Big Bang during a period of accelerated expansion, termed inflation. These early inhomogeneities were gravitationally amplified as the Universe expanded. Eventually, material contained in initially overdense regions began to collapse. Small objects were the first to form and these later merged together to form larger and larger structures. This picture has received spectacular confirmation from a series of experiments designed to probe anisotropies in the cosmic microwave background radiation. As a result of these experiments, cosmologists now believe they know the values of most of the basic parameters of the Universe (for example the density parameter R, the value of the Hubble and cosmological constants and the amplitude of the power spectrum of initial fluctuations) to better than 10%. The development of structure in the dark matter component of the Universe is also extremely well understood, thanks to a program of detailed numerical simulations that have elucidated how structures such as clusters form from the merging of smaller lumps as they stream in along filaments of dark matter. In spite of these advances, the formation and evolution of galaxies remains poorly understood. In the standard picture, a galaxy will form when gas is able to reach high enough densities to cool, sink to the centre of a high density lump of dark matter (called a “halo”) and form stars. What happens to the galaxy after that de9e:ids cn the interplay between a host of complex physical processes. The most massive stars quickly run out of fuel and end their lives as supernovae. These supernovae may be responsible for reheating gas and expelling heavy elements from the galaxy, thereby altering its structure and slowing down the rate at which it can form stars. Galaxies will also merge with each other as their surrounding dark matter halos coalesce. During these mergers gas is compressed and the star

En este trabajo, empleamos la Simulación del Millennium, la cual constituye la mayor simulación de formación de la estructura llevada a cabo hasta el momento, para estudiarlas implicaciones del proceso de agregación jerárquica de la estructura en la formación y evolución química y dinámica de galaxias elípticas masivas, enanas irregulares y semejantes a la Vía Láctea. In this work, we employ the Millennium Simulation, which constitutes the largest simulation of structure formation carried out so far, to study the implications of the hierarchical agregation of the structure on the formation and, chemical and dynamical evolution of massive elliptical, dwarf irregularand Milky Way-type galaxies. Fil: De Rossi, María Emilia. Universidad de Buenos Aires - CONICET. Instituto de Astronomía y Física del Espacio (IAFE). Buenos Aires. Argentina Fil: Tissera, P. B.. Universidad de Buenos Aires - CONICET. Instituto de Astronomía y Física del Espacio (IAFE). Buenos Aires. Argentina Fil: De Lucia, Gabriela. Fil: Kauffmann, G.. Max-Planck-Institut für Astrophysik. Garching. Alemania

Basing on the results of behavioural audiometry, MIRA (Multichannel Infant Reflex Audiometry) with and without biofeedback as well as in several cases also from the ABR, the authors demonstrate the advantages of the combination of curve analysis with behavioural observation compared with isolated looking at physiological curves or at the behaviour. The results were obtained from 100 babies in their first year of life accepted in sequence for testing their hearing; nearly one half of them had considerable hearing risks, most of them having been subjected to several different hearing tests.

To evaluate the clinical efficiency of percutaneously placed metallic stents in patients with malignant biliary obstruction.In a prospective study 92 consecutive patients with malignant biliary obstruction were treated percutaneously with expandable metallic stents. Technical and clinical parameters during the procedure and regular follow-up were evaluated.Technical and clinical success rates were 100 and 91% respectively. During stent implantation we observed no severe complications. 30-day morbidity and mortality were 12 and 13% respectively. Late complications occurred in 35%, in 20.7% due to reocclusion of the bile ducts which was treated successfully in 17/19 patients. 75% of patients benefited from the procedure. Primary and secondary patency were 79.3 and 97.8%, respectively.Percutaneous transhepatic implantation of expandable metallic stents is a reliable and safe therapy for malignant jaundice and has a definite positive impact on the patients quality of life.

To determine the clinical efficacy of pulse-spray thrombolysis.In a prospective trial 28 patients with acute arterial (n = 14) and bypass (n = 14) occlusions of the lower extremities were treated with pulse spray thrombolysis. 23/28 legs were at risk.Technical and clinical success were 89% and 68% respectively. Time interval until restitution of antegrade flow was less than two hours, the median duration of the complete intervention was 17 hours. Two patients (7.1%) needed transfusions for inguinal haematomas. After six months 50% of occluded segments remained patent, secondary patency is comparable at 53%. Bypasses show significantly lower patency (p = 0.04) and higher amputation (p = 0.009) rates than native arteries. Bad run-off (or = 1 artery patent) is a significant predictor for clinical failure and early amputation.The distinct advantage of pulse-spray thrombolysis is fast restoration of antegrade flow and thereby effective treatment of acute ischaemia. The complication rate is low without associated mortality.

The analysis of disk formation in this paper is based on the White & Rees (1978) picture, in which disk galaxies form by continuous cooling and accretion of gas within a merging hierarchy of dark matter halos. A simple Kennicutt law of star formation for disks, based on a single-fluid gravitational stability model, is introduced. Since the gas supply in the disk is regulated by infall from the surrounding halo, the gas is always maintained at a critical threshold surface density Σ C , where Σ C ∝ Vc/R. Chemical enrichment of the disks occurs when the surrounding hot halo gas is enriched with heavy elements ejected during supernova explosions. This gas then cools onto the disk producing a new generation of metal-rich stars.

We use the semi-analytic models of galaxy formation developed by Kauffmann, White \& Guiderdoni to generate predictions for the observed properties of cluster and group galaxies at redshifts between 0 and 0.6. We examine four sets of cosmological initial conditions: low-density CDM models with and without cosmological constant, a flat CDM model and a mixed dark matter model. These models were selected because they span a wide range in cluster formation epoch. The semi-analytic models that we employ are able to follow both the evolution of the dark matter component of clusters and the formation and evolution of the stellar populations of the cluster galaxies. We are thus able to generate model predictions that can be compared directly with the observational data. In the low-density CDM models, clusters form at high red- shift and accrete very little mass at recent times. Our models predict that essentially no evolution in the observed properties of clusters will have occurred by a redshift of 0.6, in direct contradiction with the data. In contrast, in the MDM model, both galaxies and clusters form extremely late. This model predicts evolution which appears to be too extreme to be in agreement with the observations. The flat CDM model, which is intermediate in structure formation epoch, is most successful. This model is able to account for the evolution of the blue fraction of rich clusters with redshift, the relationship between blue fraction and cluster richness at different epochs, and the changes in the distribution of the morphologies of cluster galaxies by a redshift of 0.4., Latex file, 12 pages, postscript figures on request, 994

The widths of the azygos vein were measured in 150 patients and correlated with the pressure in the right heart-atrium. We found a significant logarithmic correlation (r = 0.8) between the two parameters. Radiologic measurement of the width of V. azygos in chest radiographs or CT is useful to evaluate the function of the right heart.

Visual ability and compensatory eye movements during defined vertical oscillation were investigated in 20 patients with unilateral lesions of labyrinthine function and in 20 normal subjects. Oscillation frequencies were performed at the rate of 1 to 1.5 Hz with an amplitude of 5 cm, comparative to head locomotions of a running person. In synchronism with this, the visual function was tested with Landolt rings. Patients complaining of subjective visual disturbance during walking and running, also presented a measurable blur of vision under test conditions. In addition, eye movements were recorded and classified into three types. However, these eye movements showed no relation to gaze function. Our results suggest that the otolith-ocular reflex may participate in adjusting the vertical eye position during vertical stimulations at low frequencies. The effect of visual disturbances in patients with labyrinthine lesions is explained by the "efference-copy" initially described by von Holst. The efference-copy is responsible for the neutralisation of provoked retinal perceptions.

Ein kurzer Rechteckreiz („Click“) erregt die basalen Abschnitte der Cochlea einige Millisekunden fruher als die weiter apikal gelegenen. Es stellt sich daher die Frage, ob durch Verwendung von Reizen, die diese cochlearen Laufzeitunterschiede kompensieren, eine verbesserte Synchronisation der neuronalen Entladungen und somit eine grosere Amplitude der auditorisch evozierten Hirnstammpotentiale erreicht werden kann (Kauffmann 1989).

The five years survival rates of patients with non-operable non-small cell lung carcinoma are between 6% and 9%. Multiple attempts have been made to improve the response rate and the survival of these patients with different chemo- and radiotherapy schemes. The systemic chemotherapy with cisplatin-vindesine is until now one of the most active treatments with a response rate of 40%, but it is limited because of its side effects and toxicity. Eleven patients are treated one to four times with an intraarterial infusion of 3 mg/m2 vindesine and 20 mg/m2 cisplatin into the tumor-feeding bronchial artery combined with a simultaneous radiotherapy (60 Gy). Until now no major side effects occurred and the systemic toxicity was insignificant. An objective tumor response was encountered in 7/11 patients. The intraarterial chemotherapy combined with radiotherapy is strictly local and therefore effective especially in patients with limited or locally advanced disease.

Basing on the results of behavioural audiometry, MIRA (Multichannel Infant Reflex Audiometry) with and without biofeedback as well as in several cases also from the ABR, the authors demonstrate the advantages of the combination of curve analysis with behavioural observation compared with isolated looking at physiological curves or at the behaviour. The results were obtained from 100 babies in their first year of life accepted in sequence for testing their hearing; nearly one half of them had considerable hearing risks, most of them having been subjected to several different hearing tests.

In Figure 6 we inadvertently labeled the proxy circular velocity as the virial velocity of the dark matter halo instead of what is actually plotted, the maximum circular velocity of the dark matter halo. The maximum halo circular velocity is a much better estimate of the disk V_c than is V_vir. This confusion influenced the discussion of the Tully-Fisher relation in our paper. In fact, Figure 6 demonstrates that it is possible to simultaneously reproduce both the local Tully-Fisher relation and luminosity function using semi-analytic techniques applied to the standard LCDM cosmology, thus contradicting previous studies of this issue and our own discussion in Section 3.6.

We analyze the K-band Hubble diagram for a sample of brightest cluster galaxies (BCGs) in the redshift range 0 < z < 1. We confirm that the scatter in the absolute magnitudes of the galaxies is small (0.3 magnitudes). The BCGs exhibit very little luminosity evolution in this redshift range: if q0 = 0.0 we detect no luminosity evolution; for q0 = 0.5 we measure a small negative evolution (i.e., BCGs were about 0.5 magnitudes fainter at z = 1 than today). If the mass in stars of these galaxies had remained constant over this period of time, substantial positive luminosity evolution would be expected: BCGs should have been brighter in the past since their stars were younger. A likely explanation for the observed zero or negative evolution is that the stellar mass of the BCGs has been assembled over time through merging and accretion, as expected in hierarchical models of galaxy formation. The colour evolution of the BCGs is consistent with that of an old stellar population (zform > 2) that is evolving passively. We can thus use evolutionary population synthesis models to estimate the rate of growth in stellar mass for these systems. We find that the stellar mass in a typical BCG has grown by a factor ≃ 2 since z ≃ 1 if q0 = 0.0 or by factor ≃ 4 if q0 = 0.5. These results are in remarkably good agreement with the predictions of semi-analytic models of galaxy formation and evolution set in the context of a hierarchical scenario for structure formation.

A new method of embolisation with a dilatation catheter is described as an example in a case with traumatic aneurysm and an a.v. fistula of the vertebral artery. The lesion was temporarily occluded with a conventional catheter for angioplasty and operated upon. The method is available for e.g. rapid management in case of imminent rupture of traumatic aneurysms, multiple lesions of vessels and for operative reconstruction of traumatised arteries.

The value of the catheter occlusion therapy is analyzed in 92 cases retrospectively, and the indication, and complication risk of these procedures are considered. In the following vessel areas occlusion with different methods have been performed with decreasing frequency; kidneys, pelvis, legs, gastrointestinal tract, external carotid and internal carotid artery. Serious complications have been observed in therapeutic investigations at the head, especially in occlusions of the external carotid artery. In this group embolisation therapy should be performed with strict indication only.

Renal embolization was performed in 12 dogs using the Seldinger technique and microspheres 250 ± 40 µm in diameter. Periodical arteriography, microangiographies and histological analysis were carried out to control the efficacy of embolization. As a result, renal arteries could be embolized with microspheres, however, because of statistical distribution there were histologically anemic and normal parenchyma situated closely together. In more than 50% there was a reflux of microspheres which could only be detected by histological examination, while angiographies showed a totally normal vascular pattern. Microspheres should not be used in clinical embolization. Experimental investigation of embolization materials must almost embrace histological analysis.

A comparative study of the molecular structure of the 1:2 complex of beryllium chloride with methyl cyanide is carried out by X-ray diffraction and MO calculations of both CNDO and ab initio type. The site symmetry of the beryllium atom in BeCl2(NCCH3)2 is shown to be 4-coordinate, deformed tetrahedral; a novel feature lies in a slight “crab-claw” configuration assumed by the nitrile ligands, which are coordinated by nitrogen to the metal atom. Experimentally determined interatomic distances and bond angles are compared with those predicted by MO treatment involving energy minimization. Application of the computational method in the case of the microcrystalline, nonisotypical compound BeCl2(NCCl)2 suggests that the latter molecule also has a distorted tetrahedral structure, but with Cl-Be-C1 and N-Be-N bond angles which are respectively greater and smaller than those of the corresponding methyl cyanide complex.

1. Die Mikrophonpotentiale werden in die Komponenten CM+ und CM− zerlegt, diese werden getrennt untersucht. Ihre Intensitatsfunktion ist etwa gleich, CM− wird jedoch durch Blockierung des aeroben und anaeroben Zellstoffwechsels, durch Hemmung aktiver Transporte sowie durch Abkuhlung starker betroffen als CM+. 2. CM− ist auf die Energiegewinnung aus dem aeroben Stoffwechsel angewiesen, fur die Erzeugung von CM+ reicht der weniger effiziente anaerobe Stoffwechsel aus. 3. Ein Modell der CM-Entstehung bei den Sauropsiden wird diskutiert; dabei wird die Zusammensetzung der CM aus 2 Komponenten berucksichtigt. 4. In diesem Modell wird die hohere Ouabain- (und Stoffwechsel-) Empfindlichkeit von CM− gegenuber CM+ darauf zuruckgefuhrt, das CM− von einem aktiven Ionentransport in den Haarzellen abhangt; die ionalen Voraussetzungen fur CM+ beruhen dagegen auf den Ionen-Gradienten zwischen Endo- und Perilymphe. 5. Das Summationspotential ist im physiologischen Schalldruckbereich kaum nachweisbar. Das endocochleare Potential betragt im Mittel 1,2 mV (positiv gegenuber der Scala vestibuli); eine Stoffwechselabhangigkeit wurde nicht gefunden. 6. Das Aktionspotential wird von den Versuchsbedingungen ahnlich wie CM− beeinflust; Unregelmasigkeiten werden auf sekundare Einflusse (Kreislauf, ZNS) zuruckgefuhrt.

Three rare variations of the large arteries of the thigh are known: Hypoplasia or aplasia of the superficial femoral artery in combination with persistent sciatic artery which normally is present during embryogenesis for a few days only. Typical finding is a large dorsal artery in the thigh accompanied with a hypoplastic superficial femoral artery. For the first time angiography of this vascular situation is shown in two projections. Complications of persistent sciatic artery include aneurysm (25%) and occlusion (embolic or thrombotic). Duplication of the superficial femoral artery. Absence or duplication of the deep femoral artery caused by separately originating branches. Knowledge of embryogenesis of the vessels helps to understand these artery variations.

The arterial blood supply of the anastomosis in 6 stomach resected dogs (Billroth II) is examined by common angiographic technique in vivo, microangiography, and microscopy. In all animals there are at the site of the gastrojejunostomy bizarre tortuous vessels which cross the anastomosis. These arteries have a diameter between 50 to 2000 mu. They are newly formed vessels which cannot be demonstrated by common coeliaco- and mesentericography in animal experiments or in patients.