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Assume that p, q, and kare integers for which the conditions 1≤p,q≤10and 2≤k≤10are satisfied. The initial values G0=0, G1=1, together with the recursive rule Gm=kGm-1+Gm-2define the non-negative integer sequence {Gm}m=0∞. In this paper, we solve completely the diophantine equation G1p+2G2p+⋯+ℓGℓp=Gnqin the positive integers k,p,q,ℓ,nunconditionally for ℓand n. The method works, at least in theory for arbitrary positive integers p, q, and k.

Because alliances are so important to Eli Lilly's long-term success, we have developed a distinct approach to managing alliances on the basis of our experience and extensive research of what [...]

While the facilitatory and inhibitory effects of intermittent theta burst stimulation (iTBS) and continuous TBS (cTBS) protocols have been well documented on motor physiology, the action of TBS protocols on prefrontal functioning remain unclear. Here we asked whether iTBS or cTBS can differentially modulate reward-related signaling in the anterior midcingulate cortex (aMCC).

Byline: Gueth Braddock, January 2004 During the last several months of 2003 and early 2004, DEMCO personnel conducted a survey of the entire DEMCO service territory for the purpose of [...]

This volume contains papers originally presented or inspired by the Fifth International Conference on Uniform Distribution Theory which was held in Sopron, Hungary, July 5-8, 2016.

Context. L1157-mm is a low-mass protostar driving an outflow which is considered the proto-type of the so-called chemically active outflows. In particular, the blue-shifted lobe B1 stands out for its rich mm-wave spectrum.

Aims. We study the molecular content and chemistry of a circumstellar disk surrounding the Herbig Ae star AB Aur at (sub-)millimeter wavelengths. Our aim is to reconstruct the chemical history and composition of the AB Aur disk and to compare it with disks around low-mass, cooler T Tauri stars.

Context.The jet-disk connection is an important part of the star formation process. HH 30 is a rare and beautiful example of a system exhibiting a flared edge-on disk, an optical jet and a CO molecular outflow. A recent analysis of the jet wiggling has revealed that the central star is in reality a binary object. Therefore, the dust and gas disk observed around HH 30 is circumbinary.

Context.The bipolar HH 212 outflow has been mapped in SiO using the extended configuration of the Plateau de Bure Interferometer (PdBI), revealing a highly collimated SiO jet closely associated with the H2jet component.

Aims.To constrain the ionization fraction in protoplanetary disks, we present new high-sensitivity interferometric observations of N2H+in three disks surrounding DM Tau, LkCa 15, and MWC 480.

Context.In young stars, jets are believed to play a role in removing angular momentum from the circumstellar disk, allowing accretion onto the central star. Recent results suggest that in earlier phases of star formation, SiO might trace the primary jet launched close to the protostar, but further observations are required in order to reveal the properties of this molecular component.

Context.HH 30 is a well-known Pre-Main-Sequence star in Taurus. HST observations have revealed a flared, edge-on disk driving a highly-collimated optical jet, making this object a case study for the disk-jet-outflow paradigm.

We present high angular resolution interferometric observations of the dust continuum at 2.7 and 1.3 mm, and of the HC3N ($J=12\to11$) and C18O ($J=2\to1$) emission around L1157-mm, a Class 0 object that drives a spectacular molecular outflow. The millimeter dust emission is clearly resolved into two components, a flattened compact source of ~$450\times250$AU at 1.3 mm, and mass ~0.1 $M_\odot$, plus an extended envelope of ~3000 AU at 1.3 mm, and mass ~1.1 $M_\odot$. The millimeter spectral index varies throughout the region, with the lower value found toward the compact protostar, possibly indicating grain growth in the denser regions. A strong interaction between the molecular outflow and the close protostellar environment is taking place and affects the structure of the innermost parts of the envelope. This is shown by the spatial coincidence between the molecular outflow and the dust (1.3 mm continuum) and HC3N emission: both tracers show structures associated to the edges of the outflow lobes. Basically, the global picture sketched for the Class 0 object L1157-mm by Gueth et al. ([CITE]) is supported. We find possible evidence of infall, but we do not detect any velocity gradient indicative of a rotating circumstellar disk.

We present new high-sensitivity 1.3 mm bolometer observations of the young outflow L?1157. These data show that the continuum emission arises from fourdistinct components: a circumstellar disk, a protostellar envelope, an extended flattened envelope – the dense remnant of the molecular cloud in which the protostar was formed –, and the outflow itself, which represents ~20% of the total flux. The outflow emission exhibits two peaks that are coincident with the two strong shocks in the southern lobe of L?1157. We show that the mm continuum is dominated by thermal dust emission arising in the high velocity material. The spectral index derived from the new 1.3 mm data and 850 µm observations from Shirley et al. ([CITE]), is ~5 in the outflow, significantly higher than in the protostellar envelope (~3.5). This can be explained by an important line contamination of the 850 µm map, and/or by different dust characteristics in the two regions, possibly smaller grains in the post-shocks regions of the outflow. Our observations show that bipolar outflows can present compact emission peaks which must not be misinterpreted as protostellar condensations when mapping star forming regions.

We present a high-angular-resolution molecular line and millimeter continuum study of the massive star formation site IRAS05358+3543. Observations with the Plateau de Bure Interferometer in CO 1–0, SiO  and H13CO+1–0 reveal at least three outflows which cannot be separated in single-dish data. Observations at millimeter and sub-millimeter wavelengths from the IRAM 30 m telescope and the CSO provide additional information on the region. The most remarkable feature is a highly collimated (collimation factor ~10) and massive (>10 $M_{\odot}$) bipolar outflow of ~1 pc length, which is part of a quadrupolar outflow system. The three observed molecular outflows forming the IRAS05358+3543 outflow system resemble, in structure and collimation, those typical of low-mass star-forming regions. They might therefore, just like low-mass outflows, be explained by shock entrainment models of jets. We estimate a mass accretion rate of ~$10^{-4}~M_{\odot}$/yr, sufficient to overcome the radiative pressure of the central object and to build up a massive star, lending further support to the hypothesis that massive star formation occurs similarly to low-mass star formation, only with higher accretion rates and energetics. In the millimeter continuum, we find three sources near the center of the quadrupolar outflow, each with a mass of 75–100 $M_{\odot}$. These cores are associated with a complex region of infrared reflection nebulosities and their embedded illuminating sources. The molecular line data show that SiO is found mostly in the outflows, whereas H13CO+traces core-like structures, though likely with varying relative abundances. Thermal CH3OH comprises both features and can be disentangled into a core-tracing component at the line center, and wing emission following the outflows. A CO line-ratio study (using data of the $J=1$–0, 2–1 and 6–5 transitions) reveals local temperature gradients.

We present an interferometric study of the CO $J\!=\!1\!\rightarrow\!0$line emission in the HH 288 molecular outflow. The IRAM Plateau de Bure interferometer was used to obtain an 11-field mosaic covering the whole flow (~2 pc) with an angular resolution of about $3.5''$(7000 AU at a distance of 2 kpc). The data were complemented with short-spacings derived from IRAM 30-m observations. The exciting source of HH 288, IRAS 00342+6347, is a young (dynamical age of the outflow $\simeq$a few 104years) intermediate-mass (bolometric luminosity ${\simeq} 500 L\mathord\odot$, envelope mass $\simeq$6 to $30 M\mathord\odot$) embedded protostar. This source is likely to be an intermediate-mass counterpart of a classical Class 0 low-mass protostar. HH 288 is actually a quadrupolar outflow, and the angular resolution provided by the interferometric observations allows us to rule out models involving limb-brightened walls of a wide-angle single flow to explain such a morphology. The presence of two protostars in the central condensation is the most appealing explanation to account for the presence of the two flows. While the small East-West flow has a quite simple morphology and kinematics, the large North-South flow includes several overlapping structures, created by successive ejection events. Large collimated limb-brightened cavities are observed, with high-velocity material located along or near the flow axis. The internal structure of HH 288, including morphological coincidence between the CO and H2emission, supports prompt entrainment at the head of large bow-shocks as the main formation process of molecular outflows from intermediate-mass protostars.

Context. The disk-outflow connection is thought to play a key role in extracting excess angular momentum from a forming proto-star. Although jet rotation has been observed in a few objects, no rotation of molecular outflows has been unambiguously reported so far.Aims. We report new millimeter-interferometric observations of the edge-on T?Tauri?star ? disk system in the isolated Bok globule CB?26. The aim of these observations was to study the disk-outflow relation in this 1?Myr old low-mass young stellar object.Methods. The IRAM PdBI array was used to observe 12CO(2?1) at 1.3?mm in two configurations, resulting in spectral line maps with 1.5???resolution. We use an empirical parameterized steady-state outflow model combined with 2-D line radiative transfer calculations and ?2-minimization in parameter space to derive a best-fit model and constrain parameters of the outflow.Results. The data reveal a previously undiscovered collimated bipolar molecular outflow of total length ?2000?AU, escaping perpendicular to the plane of the disk. We find peculiar kinematic signatures that suggest that the outflow is rotating with the same orientation as the disk. However, we could not ultimately exclude jet precession or two misaligned flows as possible origins of the observed peculiar velocity field. There is indirect indication that the embedded driving source is a binary system, which, together with the youth of the source, could provide a clue to the observed kinematic features of the outflow.Conclusions. CB?26 is so far the most promising source in which to study the rotation of a molecular outflow. Assuming that the outflow is rotating, we compute and compare masses, mass flux, angular momenta, and angular momentum flux of the disk and outflow and derive disk dispersal timescales of 0.5 ...1?Myr, comparable to the age of the system.

Context. Recent modeling based on unresolved infrared observations of the spectral energy distribution (SED) of GM?Aurigae suggests that the inner disk of this single TTauri star is truncated at an inner radius of 25?AU.Aims. We attempt to find evidence of this inner hole in the gas distribution, using spectroscopy with high angular resolution.Methods. Using the IRAM array, we obtained high angular resolution (~1.5?) observations with a high S/N per channel of the 13CO?J=2-1?and C18O?J=2-1?and of the 13CO?J=1-0?lines. A standard parametric disk model is used to fit the line data in the Fourier-plane and to derive the CO?disk properties. Our measurement is based on a detailed analysis of the spectroscopic profile from the CO?disk rotating in Keplerian velocity. The millimeter continuum, tracing the dust, is also analyzed.Results. We detect an inner cavity of radius 19?? 4?AU at the 4.5??level. The hole manifests itself by a lack of emission beyond the (projected) Keplerian speed at the inner radius. We also constrain the temperature gradient in the disk.Conclusions. Our data reveal the existence of an inner hole in GM?Aur?gas disk. Its origin remains unclear, but can be linked to planet formation or to a low mass stellar companion orbiting close to the central star (~5-15?AU). The frequent finding of inner cavities suggests that either binarity is the most common scenario of star formation in Taurus or that giant planet formation starts early.

The identification of glypican-3 (GPC3) expression in malignant neoplasms is potentially of interest because GPC3 might represent a therapeutic target. Tissue microarrays containing tissue cylinders from 308 patients with ovarian carcinomas were used for an immunohistochemical study. There were 255 serous, 38 endometrioid, and 15 clear-cell carcinomas included. From 76 patients, paired tissue samples of primary serous ovarian carcinomas and their corresponding recurrences after platinum-based chemotherapy were available. Glypican-3 was expressed in a total of 17.9% of ovarian carcinomas and was strongly associated with the clear-cell histotype (P= 0.0001). Glypican-3 expression was not associated with tumor stage. Positive staining for GPC3 was also observed in a significant fraction of recurrent carcinomas but was not particularly associated with chemoresponse. In conclusion, our data show that GPC3 is observed in a significant fraction of primary and corresponding recurrent ovarian carcinomas. Glypican-3 may therefore represent a potential target for (second-line) therapy in ovarian cancer.

In this paper the cyclic stress–strain response, low cycle fatigue (LCF) behaviour, and evolution of dislocation structures under LCF loading in the case of a low carbon microalloyed steel are discussed. The cyclic stress response revealed cyclic softening resulting from the propagation of Lüders bands. The experimental LCF life was compared with the life predicted using Tomkins’ model and the modified universal slopes (MUS) equation. While the life predicted by Tomkins’ model showed good correlation with the experimental results, the life predicted using the MUS equation grossly overestimated the life. Inclusion induced delaminations under cyclic loading were thought to be responsible for the overestimation by the MUS equation. Low energy dislocation structures, i.e. cells, were observed near the fracture surfaces. Interrupted tests revealed cell formation after 10 cycles at a total strain amplitude of 0·3%.

gamma-Tubulin, a recently discovered member of the tubulin superfamily, is a peri-centriolar component considered to be essential for microtubule nucleation. Mouse oocytes and early embryos lack centrioles until the blastocyst stage. Thus, early mouse embryos allowed us to study the location of gamma-tubulin in animal cells in the absence of centrioles. For this, we used an antiserum directed against a specific peptide of the gamma-tubulin sequence, which is conserved among species. This serum has been characterised both in PtK2 and mouse cells. We found that it specifically-stained the spindle poles and the cytoplasmic microtubule organizing centers in metaphase II oocytes and the spindle poles in mitosis during the cleavage stages. In contrast, no interphase staining could be detected during cleavage. Since the overall level of gamma-tubulin did not decrease during interphase, as shown by immunoblotting experiments, this absence of staining during interphase is probably due to a cytoplasmic dispersion of gamma-tubulin. A single dot-like interphase reactivity appeared at the 32-cell stage. In parallel, electron microscopy studies allowed us to detect centrioles for the first time at the 64-cell stage. The possible roles of gamma-tubulin in microtubule nucleation and in centrosome maturation are discussed.

Compaction of the mouse embryo, which takes place at the 8-cell stage, is dependent upon the adhesion molecule E-cadherin (uvomurulin), but does not require protein synthesis, suggesting that post-translational modification(s) is (are) implicated in the setting up of this phenomenon. The demonstration recently that E-cadherin is phosphorylated at the 8-cell stage just before compaction supports this theory. In this work we used 6-dimethylaminopurine, a serine-threonine kinase inhibitor, to investigate the role of protein phosphorylation in compaction of mouse embryos. 6-dimethylaminopurine is able to induce cell flattening and gap junction formation prematurely at the 4-cell stage; however, it does not induce cell surface polarization, as occurs during normal compaction. 6-dimethylaminopurine-induced premature flattening is inhibited when the embryos are cultured in the presence of an anti-E-cadherin antibody or without extra-cellular Ca2+, demonstrating that this process requires functional E-cadherin; whereas cell flattening and gap junction formation take place in the absence of E-cadherin phosphorylation, suggesting that its phosphorylation is not required normally for these events. The relationship between E-cadherin-mediated cell flattening and gap junction formation during compaction is discussed.

It has been claimed repeatedly that gamma-tubulin is exclusively localized at the spindle poles in mitotic animal cells, where it plays a role in microtubule nucleation. In addition to this localization, we have observed a gamma-tubulin-specific staining of the mitotic spindle in several animal cells (human, kangaroo rat, mouse, Chinese hamster, Xenopus and Drosophila) using five polyclonal antibodies raised against unique gamma-tubulin sequences and four different fixation protocols. In HeLa and PtK2 cells, gamma-tubulin was detected in the mitotic spindle from late prometaphase to telophase. In contrast, in other cell types, it was detected in metaphase only. In all cases we failed to detect gamma-tubulin in the short aster microtubules at the spindle poles. Electron microscopic observation revealed that at least part of the gamma-tubulin localized on the surface of spindle microtubules with a preferential distribution along kinetochore microtubules. In HeLa cells, the amount of antigenic gamma-tubulin was fairly constant in the spindle poles during mitosis from prometaphase to telophase. In contrast, gamma-tubulin appeared in the mitotic spindles in prometaphase. The amount of gamma-tubulin decreased in telophase, where it relocalized in the interzone. In metaphase cells about 15-25% of the total fluorescence was localized at the spindle poles, while 75-85% of the fluorescence was distributed over the rest of the spindle. These results suggest that the localization and timing of gamma-tubulin during the cell cycle is highly regulated and that is physiological role could be more complex and diverse than initially assumed.

NuMA is a component of the nuclear matrix which may play a structural role in the architecture of the interphase nucleus. During apoptosis NuMA is redistributed within the nucleus and is proteolysed from a 238-kDa form to a 180- to 200-kDa form. Here we show that the cleavage site leading to the stable fragment occurs between residues 1701 and 1725. Both the changes in morphology associated with apoptosis and the cleavage of NuMA were retarded by treatment with TPCK but not by treatment by other protease inhibitors including ICE inhibitor II.

We introduce broadcasting source-addressed messages as a basic communication form in distributed computer systems for process control. Broadcasting is the delivery of a message to all computer nodes in a distributed system. Each broadcast message is labeled by a source address, which is a unique identifier that reflects the place where the message is created. A node interested in messages of a certain source can filter them from the transmission channel by performing an associative address matching. Broadcasting is an asynchronous communication between a sender and anonymous receivers. The presented broadcast protocols are particularly well suited for distributed control systems, where real-time date from a source are usually needed by more than one receiving node. The advantages of the proposed broadcast mechanism over conventional destination-addressed message passing are: no side effects, i.e. messages from different sources cannot interfere with each other at a destination; convenient monitoring of running systems; easy system extension at run time. Two realized distributed computer systems for process control are described.

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During preimplantation development of the mouse embryo, a layer of outer cells differentiates into a perfect epithelium, the trophectoderm. The divergence between the trophectoderm and the inner cell mass takes place from the 8-cell stage to the 64-cell stage and precedes their commitment at the blastocyst stage. In this work, we have investigated the expression of gp330, a 330 x 10(3) M(r) glycoprotein found in clathrin-coated areas of the plasma membrane of some epithelial cells characterized by a high level of endocytic activity. Our results show that gp330 is first synthesized in 16-cell stage embryos and that its appearance is restricted to outer cells until the blastocyst stage. Furthermore, its expression is repressed in inner cells at a post-transcriptional level, probably through the development of extensive cell-cell contacts.

Nuclear Mitotic Apparatus protein (NuMA) is a 238-kDa protein of the nuclear matrix in interphase that relocates to the spindle poles in mitosis. The globular tail domain (residues 1701 to 2115) contains the nuclear targeting sequence, the site for binding to the mitotic spindle as well as a site responsible for nuclear reformation. To more precisely map these sites, we inserted full-length human NuMA and 16 derivatives with increasing truncations of the tail domain into the pCMV5 vector and induced transient expression. NuMA was found in the interphase nucleus of all transfected BHK cells expressing either full-length NuMA or NuMA mutant proteins ending at or after residue 2005. In contrast, mutants ending at or before residue 2003 remained in the cytoplasm. In the full-length NuMA molecule, point mutations at position 1988 or 1989 or a double mutation at residues 2004 and 2005 cause NuMA to accumulate in the cytoplasm of both BHK and HeLa cells. The combined results indicate a bipartite nuclear location signal involving the sequences RKR (1987–1989) and KK (2004–2005) which are separated by 14 amino acid residues. In 30% of BHK cells transfected by the full-length clone, cytoplasmic aggregates of NuMA that colocalize with the centro- somes were documented in addition to the nuclear staining. In cells with large aggregates the cytoplasmic microtubular profile was disturbed. Observation of micronuclei formation suggests that a region important for normal nuclear reformation lies in the C-terminal 130 residues. Finally, NuMA mutant proteins ending at or after residue 1800 bound to the spindle poles of mitotic cells, while NuMA proteins ending at or before residue 1750 did not.

Transient overexpression of nuclear mitotic apparatus protein (NuMA) in HeLa cells results in ordered lattices which can fill the nucleus and which are stable to detergent extraction. Electron microscopy reveals a quasi-hexagonal organization with an average spacing between the vertices of ∼170 nm and short 6-nm-diameter rods connecting the vertices. Overexpression of a NuMA construct with an in-frame addition in the coiled-coil domain shows hexagons with the spacing increased by 42% while constructs with deletions in the coiled-coil domain yield hexagons with the spacing decreased by 40 and 19%. NuMA constructs truncated at residue 2005 or 2030 in the tail domain cause a drastic reorganization of nuclear components with relocation of the DNA, histone H1, and nucleoli to the nuclear rim. A construct lacking the head and much of the coiled-coil region also affects nuclear organization. In contrast, NuMA constructs truncated at residue 1950 or 1935 which lack the nuclear localization signal display normal nuclear structure but form cytoplasmic aggregates which also display hexagonal organization. Immunoelectron microscopy confirms that the nuclear lattices are built from NuMA. We discuss the importance of the different domains of NuMA for building the orderedin vivolattices and whether NuMA could play a structural role in the architecture of the normal interphase nucleus.

We have studied the distribution and the role of microtubules in the major developmental events occuring during early development of the mouse. These events are the setting up of asymmetries within blastomeres, the process of asymmetrical cell division and the changes in cellular organisation taking place during epithelial differentiation.

“Fifth generation computers” are expected to capitalize on the dramatic progress of VLSI technology, in order to offer an improved performance/cost figure. An even more important requirement, however, is that they will support by architectural means the generation, execution, and maintenance of “quality software,” as a way out of the “software crisis.” One approach towards the design and implementation of quality software is programming with abstract data types, in connection with elaborate type consistency checking. The objection raised against the abstract data type based programming style is poor run time efficiency when such programs are executed on a conventional machine. In this paper adata type architecture is described that offers efficient and convenient mechanism for constructing arbitrary data structures and encapsulating them into abstract data types, thus avoiding the inefficiency penalty mentioned above. Through a process of hierarchical decomposition, user-defined abstract data types are mapped on representations given in terms of a basicstructured machine data type. This approach combines high performance with generality and completeness. The hardware structure of the data type architecture can be classified as a strongly coupled, asymmetric multicomputer system with hierarchical function distribution among the computers. The system includes a pipeline for numerical and nonnumerical operations, performed on the vector-structured basic machine data type in the SIMD mode of operation. Software reliability and data security is enhanced through elaborate run time consistency checking. The computer, which was designed and built at the Technical University of Berlin, has recently become operational. This paper outlines the operational principle, the mechanisms, and the hardware and software structure of this innovative, fifth generation computer architecture.

Aims.We study the content in S-bearing molecules of protoplanetary disks around low-mass stars.

We analyze the long-term evolution of the fluxes of six active galactic nuclei (AGN) – 0923+392, 3C 111, 3C 273, 3C 345, 3C 454.3, and 3C 84 – in the frequency range 80−267 GHz using archival calibration data of the IRAM Plateau de Bure Interferometer. Our dataset spans a long timeline of  ≈14 years with 974−3027 flux measurements per source. We find strong (factors  ≈2−8) flux variability on timescales of years for all sources. The flux density distributions of five out of six sources show clear signatures of bi- or even multimodality. Our sources show mostly steep (α≈ 0.5−1), variable spectral indices that indicate outflow dominated emission; the variability is most probably due to optical depth variations. The power spectra globally correspond to red-noise spectra with five sources being located between the cases of white and flicker noise and one source (3C 111) being closer to the case of random walk noise. For three sources the low-frequency ends of their power spectra appear to be upscaled in spectral power by factors  ≈2−3 with respect to the overall powerlaws. In two sources, 3C 454.3 and 3C 84, the 1.3-mm emission preceeds the 3-mm emission by  ≈55 and  ≈300 days, respectively, probably due to (combinations of) optical depth and emission region geometry effects. We conclude that the source emission cannot be described by uniform stochastic emission processes; instead, a distinction of “quiescent” and (maybe multiple) “flare” states of the source emission appears to be necessary.

Context.Previous studies have found that Vega is surrounded by an extended debris disc that is very smooth in the far infrared, but displays possible clumpiness at 850   μm and dust emission peaks at 1.3 mm.

Context.Studying circumbinary disks is critical to understanding the formation mechanisms of binary stars. While optical or mid-infrared images reveal the scattered emission, millimeter observations provide direct measurements of the dust thermal emission.

Context.L1448-mm is the prototype of a low-mass Class 0 protostar driving a high-velocity jet. Given its bright H2O spectra observed with ISO, L1448-mm is an ideal laboratory to observe heavy water (HDO) emission.

Context. The outflow driven by the low-mass class 0 protostar L1157 is the prototype of the so-called chemically active outflows. The bright bowshock B1 in the southern outflow lobe is a privileged testbed of magneto-hydrodynamical (MHD) shock models, for which dynamical and chemical processes are strongly interdependent.Aims. We present the first results of the unbiased spectral survey of the L1157-B1 bowshock, obtained in the framework of the key program “Chemical HErschel Surveys of star forming regions” (CHESS). The main aim is to trace the warm and chemically enriched gas and to infer the excitation conditions in the shock region.Methods. The CO 5-4 and o-H2O 110–101lines have been detected at high-spectral resolution in the unbiased spectral survey of the HIFI-band 1b spectral window (555–636 GHz), presented by Codella et al. in this volume. Complementary ground-based observations in the submm window help establish the origin of the emission detected in the main-beam of HIFI and the physical conditions in the shock.Results. Both lines exhibit broad wings, which extend to velocities much higher than reported up to now. We find that the molecular emission arises from two regions with distinct physical conditions : an extended, warm (100 K), dense (3 × 105cm-3) component at low-velocity, which dominates the water line flux in Band 1; a secondary component in a small region of B1 (a few arcsec) associated with high-velocity, hot (>400 K) gas of moderate density ((1.0–3.0) × 104cm-3), which appears to dominate the flux of the water line at 179μm observed with PACS. The water abundance is enhanced by two orders of magnitude between the low- and the high-velocity component, from 8 × 10-7up to 8 × 10-5. The properties of the high-velocity component agree well with the predictions of steady-state C-shock models.

We present the first results of the unbiased survey of the L1157-B1 bow shock, obtained with HIFI in the framework of the key program Chemical HErschelSurvey of Star forming regions (CHESS). The L1157 outflow is driven by a low-mass Class 0 protostar and is considered the prototype of the so-called chemically active outflows. The bright blue-shifted bow shock B1 is the ideal laboratory for studying the link between the hot (~1000–2000 K) component traced by H2IR-emission and the cold (~10–20 K) swept-up material. The main aim is to trace the warm gas chemically enriched by the passage of a shock and to infer the excitation conditions in L1157-B1. A total of 27 lines are identified in the 555–636 GHz region, down to an average 3σlevel of 30 mK. The emission is dominated by CO(5–4) and H2O(110–101) transitions, as discussed by Lefloch et al. in this volume. Here we report on the identification of lines from NH3, H2CO, CH3OH, CS, HCN, and HCO+. The comparison between the profiles produced by molecules released from dust mantles (NH3, H2CO, CH3OH) and that of H2O is consistent with a scenario in which water is also formed in the gas-phase in high-temperature regions where sputtering or grain-grain collisions are not efficient. The high excitation range of the observed tracers allows us to infer, for the first time for these species, the existence of a warm (≥200 K) gas component coexisting in the B1 bow structure with the cold and hot gas detected from ground.

Context. The isocyanic acid (HNCO) has an extended distribution in the centers of the Milky Way and the spiral galaxy IC342. Based on both the morphology of the emission and the HNCO abundance with respect to H2, several authors hypothesized that HNCO could be a good tracer of interstellar shocks.Aims. We test this hypothesis by observing a well-known Galactic source whose chemistry is dominated by shocks.Methods. We observed several transitions of HNCO towards L1157-mm and two positions (B1 and B2) in the blue lobe of the molecular outflow.Results. The HNCO line profiles exhibit the same characteristics as other well-known shock tracers such as CH3OH, H2CO, SO, or SO2. The three molecules HNCO, SO2, and OCS are the only ones detected so far whose emission is more intense in B2 than in B1, making these species valuable probes of chemical differences along the outflow. The HNCO abundance with respect to H2is (0.4–1.8)×10-8in B1 and (0.3–1)×10-7in B2. These abundances are the highest ever measured, and imply an increment with respect to L1157-mm of up to a factor of 83, demonstrating that this molecule is a good shock tracer.Conclusions. we demonstrate that shocks can produce the HNCO abundance measured in galactic nuclei and even higher values. We propose that the gas phase abundance of HNCO is produced by both grain mantle erosion by the shock waves and by neutral-neutral reactions in gas phase involving CN and O2. The observed anticorrelation between CN and HNCO fluxes supports this scenario. The observed similarities between the HNCO emission and sulfur-bearing molecules may be caused by formation pathways that also involve O2.

Metal hydride reduction of the chlorophosphane (I) yields the crude secondary phosphane (II) which is pyrolyzed to yield the title compound (III).