bluuebunny/crossref_metadata_2025 huggingface dataset:
Consensus conference on the appropriateness of palivizumab prophylaxis in respiratory syncytial virus disease
Authors: Pignotti Maria Serenella , Carmela Leo Maria , Pugi Alessandra , De Masi Salvatore , Biermann Klaus Peter , Galli Luisa , Vitali Rosati Giovanni , Buonocore Giuseppe , Mugelli Alessandro , Dani Carlo , Lucenteforte Ersilia , Bellini Francesca , Donzelli Giampaolo ,   Palivizumab Consensus Group
Published: September 2016

Respiratory syncytial virus infection represents a clinical burden among young children under 24 months. Palivizumab is the only drug licensed in Italy for the prevention of serious lower respiratory tract disease requiring hospitalization caused by respiratory syncytial virus in children at high risk.

However recommendations for palivizumab prophylaxis are heterogeneous. Not all the published documents agree about the clinical indications of palivizumab; this could lead to different clinical practices and concerns about the appropriateness of prophylaxis. These issues and the lack of evidence about palivizumab prophylaxis efficacy in specific medical conditions brought on the idea of a consensus conference on the current recommendations for the management and prevention of bronchiolitis, in order to share useful indications. The goal was to perform a review of the evidence regarding the efficacy and the safety of palivizumab and give recommendations in order to harmonize its use. A structured and validated method to conduct the consensus process was adopted. The consensus conference recommends palivizumab prophylaxis in infants born before 29 weeks and younger than 12 months at the start of the epidemic season. According to evidence from literature and experts’ opinion, palivizumab prophylaxis is not recommended in preterm infants of gestational age ≥29 weeks, without co‐morbidity (i.e., cardiac, bronchopulmonary diseases). The experts identified some clinical rare conditions for which the decision of prophylaxis should be entrusted to the specialists. The evaluation of the appropriateness of palivizumab prophylaxis in the single patient should be documented by the specialists. Pediatr Pulmonol. 2016;51:1088–1096. © 2016 Wiley Periodicals, Inc.
Deposition Rates from Blow‐in‐Place of Different Donor Charges: Comparison of Composition C‐4 and Shaped Charges
Authors: Diaz Emmanuela , Thiboutot Sonia
Published: September 2016

For more than 70 years, the Canadian Armed Forces (CAF) have been using the plastic explosive Composition C‐4 based mainly on the explosive hexahydro‐1,3,5‐trinitro‐1,3,5‐triazine (RDX) for various operational needs. Composition C‐4 is used as donor charge for the blow‐in‐place destruction of unexploded ordnance (UXO) by Explosive Ordnance Disposal teams and, as well, mostly used as a demolition explosive by engineering units. RDX is very stable in the environment, somewhat water‐soluble and moves relatively rapidly towards surface and groundwater bodies in Ranges and Training Areas (RTA). It is the key contaminant that triggered the closure of a major RTA in the USA and the use of C‐4 was proven to contribute to its accumulation in demolition ranges. A study was conducted to measure the deposition of RDX generated from the use of Canadian C‐4 blocks and two shaped charges for comparison purposes, as the shaped charge represents a possible alternative for C‐4 as a donor charge in blow‐in‐place operations. The shaped charges studied were the Excalibur and two diameters of the SM‐EOD suite from SAAB Bofors. These shaped charges were selected for their potential to destroy UXOs. The Excalibur shaped charge led to RDX deposition rates similar to those observed with C‐4 blocks, whereas the SM‐EOD showed forensic traces of RDX. Based on these results, SM‐EOD shaped charges provide a possible alternative to using C‐4 for blow‐in‐place (BIP) operations, as they generate only small quantities of critical contaminants (such as RDX). By eliminating the contamination from the donor charge, the BIP operation will necessarily be improved and cleaner.
On the role of the electric dipole moment in the diffraction of biomolecules at nanomechanical gratings
Authors: Knobloch Christian , Stickler Benjamin A. , Brand Christian , Sclafani Michele , Lilach Yigal , Juffmann Thomas , Cheshnovsky Ori , Hornberger Klaus , Arndt Markus
Published: September 2016

We investigate effects of a permanent electric dipole moment on matter‐wave diffraction at nanomechanical gratings. Specifically, the diffraction patterns of hypericin at ultra‐thin carbonaceous diffraction masks are compared with those of a polar and a non‐polar porphyrin derivative of similar mass and de Broglie wavelength. We present a theoretical analysis of the diffraction of a rotating dipole highlighting that small local electric charges in the material mask can strongly reduce the interference visibility. We discuss the relevance of this finding for single grating diffraction and multi‐grating interferometry with biomolecules.
Quantum holonomy theory
Authors: Aastrup Johannes , Grimstrup Jesper Møller
Published: September 2016

We present quantum holonomy theory, which is a non‐perturbative theory of quantum gravity coupled to fermionic degrees of freedom. The theory is based on a ‐algebra that involves holonomy‐diffeo‐morphisms on a 3‐dimensional manifold and which encodes the canonical commutation relations of canonical quantum gravity formulated in terms of Ashtekar variables. Employing a Dirac type operator on the configuration space of Ashtekar connections we obtain a semi‐classical state and a kinematical Hilbert space via its GNS construction. We use the Dirac type operator, which provides a metric structure over the space of Ashtekar connections, to define a scalar curvature operator, from which we obtain a candidate for a Hamilton operator. We show that the classical Hamilton constraint of general relativity emerges from this in a semi‐classical limit and we then compute the operator constraint algebra. Also, we find states in the kinematical Hilbert space on which the expectation value of the Dirac type operator gives the Dirac Hamiltonian in a semi‐classical limit and thus provides a connection to fermionic quantum field theory. Finally, an almost‐commutative algebra emerges from the holonomy‐diffeomorphism algebra in the same limit.
Detection of the cytochrome b mutation G143A in Irish Rhynchosporium commune populations using targeted 454 sequencing
Authors: Phelan Sinead , Barthe Marie‐Sophie , Tobie Camille , Kildea Steven
Published: September 2016

BACKGROUND

Rhynchosporium commune is a major fungal pathogen of barley crops, and the application of fungicides, such as quinone outside inhibitors (QoIs), plays an important role in crop disease control. The genetic mechanisms linked to QoI resistance have been identified in the cytochrome b gene, with QoI resistance conferred by the G143A substitution. The objective of this study was to develop a high‐throughput molecular assay to detect and identify mutations associated with QoI resistance within the Irish R. commune population.

RESULTS

Leaf lesions of R. commune sampled from 74 sites during 2009–2014 and isolates from 2006 and 2007 were screened for non‐synonymous mutations of the cytochrome b gene using 454 targeted sequencing. The presence of the G143A substitution was confirmed in R. commune samples at one site in 2013 and at four sites in 2014; however, the frequency of the substitution in these samples was low (2–18%). The 454 sequencing results were confirmed by PCR‐RFLP and Sanger sequencing.

CONCLUSION

The molecular assay that has been applied to this monitoring programme has shown that the application of 454 next‐generation sequencing offers the potential for high throughput and accurate characterisation of non‐synonymous mutations associated with fungicide resistance in a crop pathogen. © 2016 Society of Chemical Industry
Controversy surrounds NHS delays over commissioning PrEP
Authors: Ellison Roberta
Published: September 2016

NHS England's decision to appeal against the judgement ruling that it legally has the power to commission preexposure prophylaxis (PrEP) continues to hold up the introduction of an HIV infection prevention measure that could be hugely beneficial to individuals at high risk.
Brivaracetam in the management of epilepsy with focal seizures
Authors: Chaplin Steve
Published: September 2016

Brivaracetam (Briviact) is a new treatment for epilepsy, licensed as an adjunctive therapy in the management of partialonset (focal) seizures with or without secondary generalisation. This article describes its indications, efficacy and adverse effects.
Two Oxime‐Based {LnIII3NiII3} Clusters with Triangular {Ln3(μ3‐Ο2)}7+ Core: Solvothermal Syntheses, Crystal Structures, and Magnetic Properties
Authors: Wang Xiao‐Ting , Dong Hui‐Ming , Wang Xiu‐Guang , Yang En‐Cui , Zhao Xiao‐Jun
Published: September 2016

Two isostructural heterometallic complexes, {[Dy3Ni3(H2O)3(mpko)9(O2)(NO3)3](ClO4)·3CH3OH·3CH3CN} (1) and {[Gd3Ni3(H2O)3(mpko)9(O2)(NO3)3](NO3)·10.75CH3OH} (2) [mpkoH = 1‐(pyrazin‐2‐yl)ethanone oxime], were solvothermally synthesized by varying lanthanide ions with different magnetic anisotropy. Structural analyses revealed that both complexes contain a peroxide anion‐aggregated triangular {Ln3(μ3‐Ο2)}7+ core, which is surrounded by three NiII octahedra through threefold oxime linkages into a heterometallic hexanuclear cluster. Apparent antiferromagnetic interactions are observed between the adjacent spin carriers of 1 and 2 with the coupling constant JLn···Ni ≈ 12JLn···Ln. Additionally, 1 with highly anisotropic DyIII site shows slow magnetization relaxation under zero dc field and 2 constructed from isotropic GdIII ion displays significant cryogenic magnetocaloric effect with a maximum entropy change of 24.8 J·kg–1·K–1 at 3.0 K and 70 kOe.
Exact Poincaré constants in two‐dimensional annuli
Authors: Rummler Bernd , Růžička Michael , Thäter Gudrun
Published: September 2016

We provide precise estimates of the Poincaré constants firstly for scalar functions and secondly for solenoidal (i.e. divergence free) vector fields (in both cases with vanishing Dirichlet traces on the boundary) on 2d‐annuli by the use of the first eigenvalues of the scalar Laplacian and the Stokes operator, respectively. In our non‐dimensional setting each annulus is defined via two concentrical circles with radii and . Additionally, corresponding problems on domains , the 2d‐annuli from , are investigated ‐ for comparison but also to provide limits for . In particular, the Green's function of the Laplacian on with vanishing Dirichlet traces on is used to show that for the first eigenvalue here tends to the first eigenvalue of the corresponding problem on the open unit circle. On the other hand, we take advantage of the so‐called small‐gap limit for .
A unified beam theory with strain gradient effect and the von Kármán nonlinearity
Authors: Khodabakhshi Parisa , Reddy J. N.
Published: September 2016

In this paper, the governing equations and finite element formulations for a microstructure‐dependent unified beam theory with the von Kármán nonlinearity are developed. The unified beam theory includes the three familiar beam theories (namely, Euler‐Bernoulli beam theory, Timoshenko beam theory, and third‐order Reddy beam theory) as special cases. The unified beam formulation can be used to facilitate the development of general finite element codes for different beam theories. Nonlocal size‐dependent properties are introduced through classical strain gradient theories. The von Kármán nonlinearity which accounts for the coupling between extensional and bending responses in beams with moderately large rotations but small strains is included. Equations for each beam theory can be deduced by setting the values of certain parameters. Newton's iterative scheme is used to solve the resulting nonlinear set of finite element equations. The numerical results show that both the strain gradient theory and the von Kármán nonlinearity have a stiffening effect, and therefore, reduce the displacements. The influence is more prominent in thin beams when compared to thick beams.
Microlocal analysis of fractional wave equations
Authors: Hörmann Günther , Oparnica Ljubica , Zorica Dušan
Published: September 2016

We determine the wave front sets of solutions to two special cases of the Cauchy problem for the space‐time fractional Zener wave equation, one being fractional in space, the other being fractional in time. For the case of the space fractional wave equation, we show that no spatial propagation of singularities occurs. For the time fractional Zener wave equation, we show an analogue of non‐characteristic regularity.
Schlüsselfiguren: Raum als Gegenstand und Ressource des Wandels
Authors: Gailing Ludger , Ibert Oliver
Published: September 2016

With the notion of key players the authors tackle a major conceptual problem in recent debates on socio-spatial change. How can we conceptualize socio-scientifically what perceived wisdom among practitioners frequently maintains: the decisive role of single persons in complex processes of change? This paper seeks to identify socio-scientific concepts from several disciplinary strands, mainly from political sciences, organization and management studies and sociology that are helpful for defining key players and for understanding their contribution to processes of change. Furthermore, the authors elucidate heuristically in how far the influence of the types “leader”, “intermediary” and “governance pioneer” can also be explained in terms of how they act in space and how they mobilize spatially distributed resources. Space, it is argued, can be understood as an object of change and as a resource in processes of change.
Diffusion-Weighted Magnetic Resonance Imaging of Cholesteatoma Using PROPELLER at 1.5T: A Single-Centre Retrospective Study
Authors: Clarke Sharon E. , Mistry Dipan , AlThubaiti Talal , Khan M. Naeem , Morris David , Bance Manohar
Published: September 2016

Purpose

The purpose of this study was to evaluate the sensitivity, specificity, and positive and negative predictive values of the diffusion-weighted periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) technique in the detection of cholesteatoma at our institution with surgical confirmation in all cases.

Methods

A retrospective review of 21 consecutive patients who underwent diffusion-weighted PROPELLER magnetic resonance imaging (MRI) on a 1.5T MRI scanner prior to primary or revision/second-look surgery for suspected cholesteatoma from 2009-2012 was performed.

Results

Diffusion-weighted PROPELLER had a sensitivity of 75%, specificity of 60%, positive predictive value of 86%, and negative predictive value of 43%. In the 15 patients for whom the presence or absence of cholesteatoma was correctly predicted, there were 2 cases where the reported locations of diffusion restriction did not correspond to the location of the cholesteatoma observed at surgery.

Conclusion

On the basis of our retrospective study, we conclude that diffusion-weighted PROPELLER MRI is not sufficiently accurate to replace second look surgery at our institution.
Recognition: A Short History
Authors: Bartelson Jens
Published: September 2016

During the past decade there has been a resurgence of interest in the concept of recognition in international theory. Once the narrow concern of social theorists, the concept of recognition is nowadays invoked in at least three different senses in order to explain three different things. First, it is commonly used to explain how states and their identities are shaped by interaction, and how the modern international system has emerged as a cumulated consequence of such patterns of interaction. In this context, the concept of recognition is used to explain how states are individuated and differentiated from each other, how the international system thereby becomes stratified along status lines, as well as why conflicts over status are possible or even inevitable. Second, although the concept of recognition has long enjoyed wide currency within international legal theory, where it is used to account for what makes states legal persons and equal members of international society, recent scholarship has done much to complicate this view by pointing out how practices of inclusion often have gone hand in hand with practices of exclusion, and how this has led to an informal stratification of international society. Third, the concept has most recently been invoked to suggest how the undesirable consequences of international anarchy can be mitigated or even avoided through mutual recognition between political communities.
Swedish Feminist Foreign Policy in the Making: Ethics, Politics, and Gender
Authors: Aggestam Karin , Bergman-Rosamond Annika
Published: September 2016

In 2015, the world's first self-defined feminist government was formed in Sweden with the explicit ambition of pursuing a feminist foreign policy. This essay seeks to unpack and highlight some of the substance and plausible future directions of a feminist foreign policy. The overarching ambition is three-fold: (1) to probe the normative contents of feminist foreign policy in theory and in practice; (2) to identify a number of potential challenges and ethical dilemmas that are detrimental to gender-sensitive global politics; and (3) to advance a research agenda that can deepen the normative and ethical notions of a feminist foreign policy. Sweden's feminist foreign policy is still in the making. Its conduct is mostly incremental and focused on international agenda setting and normative entrepreneurship, which is guided by an ethically informed framework of cosmopolitanism and human rights. Yet, this essay argues that this reorientation is distinct for two reasons: First, by adopting the “F-word” it elevates politics from a broadly consensual orientation of gender mainstreaming towards more controversial politics, which explicitly seeks to renegotiate and challenge power hierarchies and gendered institutions that hitherto defined global institutions and foreign and security policies. Second, it contains a normative reorientation of foreign policy, which is guided by an ethically informed framework based on broad cosmopolitan norms of global justice and peace. The article concludes by advancing a research agenda that draws upon feminist IR theory and enhances the ethical and transformative contents of the English School by making it more gender-sensitive and appropriate for the study of feminist foreign policy.
Should International Courts Use Public Reason?
Authors: Langvatn Silje Aambø
Published: September 2016

This article assesses recent claims that international courts and tribunals can enhance their legitimacy through public reason. Section one argues that international legal scholars attribute a wide range of meanings to public reason, and goes on to provide clarification of how this range of conceptions, or ideas and ideals, referred to as public reason fits into the dominant and broadly Rawlsian tradition. Section two analyses properties and features of international courts that make public reason normatively relevant. Section three then sketches an ideal of public reason for ICs that suggests guidelines and principles to limit the discretion of judges when reasoning about morally and politically contentious issues. This ideal is designed to address a particular legitimacy concern raised against many new international courts, namely, that they engage in judicial activism, passing judgments on contentious moral and political issues without being sufficiently authorized and accountable. This ideal does not encourage the judges to engage in more judicial review, rather it seeks to restrict the judges' reasoning and judicial discretion when engaging in review and judicial development of the law. The final section compares and contrasts the proposed account of public reason to other adjudicative ideals, both from the general adjudicative accounts of Ronald Dworkin and Cass Sunstein, as well as the more ambitious and cosmopolitan accounts of public reason for ICs offered by the legal scholars Kumm, Sadurski, and Petersmann.
Accretion Onto the Milky Way: The Smith Cloud
Authors: Lockman Felix J.
Published: September 2016

Active gas accretion onto the Milky Way is observed in an object called the Smith Cloud, which contains several million solar masses of neutral and warm ionized gas and is currently losing material to the Milky Way, adding angular momentum to the disk. It is several kpc in size and its tip lies 2 kpc below the Galactic plane. It appears to have no stellar counterpart, but could contain a stellar population like that of the dwarf galaxy Leo P. There are suggestions that its existence and survival require that it be embedded in a dark matter halo of a few 108 solar masses.
Resolving the Transition from Molecular to Atomic at 1/5 Solar Metallicity in the Small Magellanic Cloud
Authors: Jameson Katherine E. , Bolatto Alberto D. , Wolfire Mark , Rubio Monica , Camus Rodrigo Herrera ,   the HS Collaboration
Published: September 2016

At a distance of 61 kpc, the Small Magellanic Cloud (SMC) affords an absolutely unique view of the low metallicity star-forming interstellar medium, providing the nearest laboratory to study processes relevant to star formation at high redshifts. We present new ALMA 7m-array maps of CO and 12CO (2-1) for one of the four observed regions in the Southwest Bar of the SMC. These maps are the first high-resolution (~6″ ~ 1.7 pc) images of CO in a molecular cloud at 1/5 Solar metallicity. We show the structure of photodissociation regions for the first time at 1/5 Solar metallicity by combining the new ALMA data with Herschel maps of [C ii] and [O i]. We present preliminary evidence that there is extended, faint 12CO (2-1) emission near where we expect the Hi-to-H2 transition. We also compare our data to the low metallicity 3D simulations by Glover & Mac Low (2011) and Shetty et al. (2011).
Astrochemistry in external galaxies: how to use molecules as probes of their physical conditions
Authors: Viti Serena
Published: September 2016

It is now well established that chemistry in external galaxies is rich and complex. In this review I will explore whether one can use molecular emissions to determine their physical conditions. There are several considerations to bear in mind when using molecular emission, and in particular molecular ratios, to determine the densities, temperatures and energetics of a galaxy, which I will briefly summarise here. I will then present an example of a study that uses multiple chemical and radiative transfer analyses in order to tackle the too often neglected ‘degeneracies’ implicit in the interpretation of molecular ratios and show that only via such analyses combined with multi-species and multi-lines high spatial resolution data one can truly make molecules into powerful diagnostics of the evolution and distribution of molecular gas.
High-J CO Intensity Measurements for Galaxies Observed by the Herschel FTS
Authors: Kamenetzky Julia , Rangwala Naseem , Glenn Jason , Maloney Philip , Conley Alex
Published: September 2016

Molecular gas is the raw material for star formation and is commonly traced by the carbon monoxide (CO) molecule. The atmosphere blocks all but the lowest-J transitions of CO for observatories on the ground, but the launch of the Herschel Space Observatory revealed the CO emission of nearby galaxies from J = 4−3 to J = 13−12. Herschel showed that mid- and high-J CO lines in nearby galaxies are emitted from warm gas, accounting for approximately 10% of the molecular mass, but the majority of the CO luminosity. The energy budget of this warm, highly-excited gas is a significant window into the feedback interactions among molecular gas, star formation, and galaxy evolution. Likely, mechanical heating is required to explain the excitation. Such gas has also been observed in star forming regions within our galaxy.

We have examined all ~300 spectra of galaxies from the Herschel Fourier Transform Spectrometer and measured line fluxes or upper limits for the CO J = 4−3 to J = 13−12, [CI], and [NII] 205 micron lines in ~200 galaxies, taking systematic effects of the FTS into account. We will present our line fitting method, illustrate trends available so far in this large sample, and preview the full 2-component radiative transfer likelihood modeling of the CO emission using an illustrative sample of 20 galaxies, including comparisons to well-resolved galactic regions. This work is a comprehensive study of mid- and high-J CO emission among a variety of galaxy types, and can be used as a resource for future (sub)millimeter studies of galaxies with ground-based instruments.
Feedback Regulated Turbulence, Magnetic Fields, and Star Formation Rates in Galactic Disks
Authors: Kim Chang-Goo , Ostriker Eve C.
Published: September 2016

We use three-dimensional magnetohydrodynamic (MHD) simulations to investigate the quasi-equilibrium states of galactic disks regulated by star formation feedback. We incorporate effects from massive-star feedback via time-varying heating rates and supernova (SN) explosions. We find that the disks in our simulations rapidly approach a quasi-steady state that satisfies vertical dynamical equilibrium. The star formation rate (SFR) surface density self-adjusts to provide the total momentum flux (pressure) in the vertical direction that matches the weight of the gas. We quantify feedback efficiency by measuring feedback yields, ηc≡ Pc/ΣSFR (in suitable units), for each pressure component. The turbulent and thermal feedback yields are the same for HD and MHD simulations, ηth ~ 1 and ηturb ~ 4, consistent with the theoretical expectations. In MHD simulations, turbulent magnetic fields are rapidly generated by turbulence, and saturate at a level corresponding to ηmag,t ~ 1. The presence of magnetic fields enhances the total feedback yield and therefore reduces the SFR, since the same vertical support can be supplied at a smaller SFR. We suggest further numerical calibrations and observational tests in terms of the feedback yields.
Properties of interstellar filaments as derived from Herschel, Planck, and molecular line observations
Authors: Arzoumanian Doris , André Philippe , Boulanger François
Published: September 2016

Recent Herschel and Planck observations of submillimeter dust emission revealed the omnipresence of filamentary structures in the interstellar medium (ISM). The ubiquity of filaments in quiescent clouds as well as in star-forming regions indicates that the formation of filamentary structures is a natural product of the physics at play in the magnetized turbulent cold ISM. An analysis of more than 270 filaments observed with Herschel in 8 regions of the Gould Belt, shows that interstellar filaments are characterized by a narrow distribution of central width sharply peaked at ~0.1 pc, while they span a wide column density range. Molecular line observations of a sample of these filaments show evidence of an increase in the velocity dispersion of dense filaments with column density, suggesting an evolution in mass per unit length due to accretion of surrounding material onto these star-forming filaments. The analyses of Planck dust polarization observations show that both the mean magnetic field and its fluctuations along the filaments are different from those of their surrounding clouds. This points to a coupling between the matter and the $\vec{B}$-field in the filament formation process. These observational results, derived from dust and gas tracers in total and polarized intensity, set strong constraints on our understanding of the formation and evolution of filaments in the ISM. They provide important clues on the initial conditions of the star formation process along interstellar filaments.
An Observational Perspective of the IMF: Progress and Challenges
Authors: Offner Stella S. R.
Published: September 2016

The stellar initial mass function (IMF) is a fundamental astrophysical quantity that impacts a wide range of astrophysical problems from heavy element distribution to galactic evolution to planetary system formation. However, the origin and universality of the IMF are hotly debated both observationally and theoretically. I review recent observations of the IMF across a variety of environments. These suggest the IMF is surprisingly invariant between star-forming regions, star clusters, and spiral galaxies but that it may also vary under extreme conditions, including within the Galactic center and early type galaxies.
Numerical simulation of star formation in filamentary dark molecular clouds
Authors: Li Pak Shing , Klein Richard I. , McKee Christopher F.
Published: September 2016

Numerical simulations of star formation faces challenges including the huge spatial dynamic range and the presence of multiply coupled highly non-linear physics, such as magnetic field, supersonic turbulence, gravitation, radiation and protostellar outflow feedback. We present in this symposium our latest high resolution adaptive mesh refinement numerical simulations of the formation of filamentary dark molecular clouds from 4.55 pc size scale down to the formation of a protostellar cluster with maximum resolution at 28 AU. The physical properties of the long braided filamentary dark cloud formed in the simulation, the magnetic field properties of the cloud clumps, and the protostellar mass function in the simulations match well with the latest observations.
From disks to planets: observational insights
Authors: Isella Andrea
Published: September 2016

The unprecedented sensitivity and imaging capabilities offered by the Atacama Large Millimeter Array (ALMA) are transforming our understanding of protoplanetary disks and, hence, of planet formation. In this brief chapter, I first discuss the main results and caveats related to the measurement of the mass of solids in protoplanetary disks based on millimeter-wave observations. I then present a recent analysis of the ALMA observations of the HL Tau disk, which suggests that the observed circular rings might be due to the tidal interaction between Saturn mass planets and the circumstellar material. In the conclusion, I argue that the existing observations of protoplanetary disks suggest that planets might form very early on, perhaps at the same time as the formation of the disk itself.
Formation of star clusters: Models and simulations
Authors: Myers Philip C.
Published: September 2016

Recent progress is reviewed in describing the physical processes of star cluster formation, from the viewpoint of theoretical models and numerical simulations. In many studies, supersonic turbulent flows structure the gas into a network of clumps, filaments, and cores. Self-gravity drives star formation, moderated by turbulence, magnetic fields, and stellar feedback. Recent models and simulations describe the core mass function, the protostar mass function, and the star-formation rate. Several simulations indicate similar protostar birthrates, a mass advantage for firstborn protostars, and accretion rates that are superthermal and nearly constant. Recently observed core-filament systems with sonic line widths and parsec lengths present challenges for turbulent models.
A multi-wavelength classification system for the evolution of star clusters
Authors: Whitmore Bradley C. , Brogan Crystal , Chandar Rupali , Evans Aaron , Hibbard John , Johnson Kelsey , Leroy Adam , Privon George , Remijan Anthony , Sheth Kartik
Published: September 2016

The availability of high spatial resolution molecular gas observations from ALMA, and similar resolution observations in the radio continuum using the VLA, is providing the opportunity to make comparisons with specific features seen in optical observations more directly than in the past. Using our ALMA observations of the Antennae galaxies as a springboard, we have compared the locations of small-scale CO (3−2) features with a variety of multi-wavelength observations, in particular optical and near-infrared imaging using both broad (UBVI) and narrow-band data (Hαand Paβ) taken with the HST, and radio (3.6 cm) continuum observations taken with the VLA. This comparison leads to the development of an evolutionary classification system which provides a framework for studying the sequence of star cluster formation and evolution, from diffuse Giant Molecular Clouds (GMCs), to proto, embedded, emerging, young, and intermediate/old star clusters. Using this evolutionary framework, we estimate the maximum age range of clusters formed in a single GMC is approximately 10 Myr. This suggests that the molecular gas is removed over this timescale, resulting in the cessation of star formation and the destruction of the GMC within a radius of about 200 pc.
HOBYS and W43-HERO: Two more steps toward a Galaxy-wide understanding of high-mass star formation
Authors: Motte Frédérique , Bontemps Sylvain , Tigé Jérémy
Published: September 2016

The Herschel/HOBYS key program allows to statistically study the formation of 10−20 M⊙ stars. The IRAM/W43-HERO large program is itself dedicated to the much more extreme W43 molecular complex, which forms stars up to 50 M⊙. Both reveal high-density cloud filaments of several pc3, which are forming clusters of OB-type stars. Given their activity, these so-called mini-starburst cloud ridges could be seen as “miniature and instant models” of starburst galaxies. Both surveys also strongly suggest that high-mass prestellar cores do not exist, in agreement with the dynamical formation of cloud ridges. The HOBYS and W43 surveys are necessary steps towards Galaxy-wide studies of high-mass star formation.
Comparison of Low-Mass and High-Mass Star Formation
Authors: Tan Jonathan C.
Published: September 2016

I review theoretical models of star formation and how they apply across the stellar mass spectrum. Several distinct theories are under active study for massive star formation, especiallyTurbulent Core Accretion,Competitive AccretionandProtostellar Mergers, leading to distinct observational predictions. These include the types of initial conditions, the structure of infall envelopes, disks and outflows, and the relation of massive star formation to star cluster formation. Even for Core Accretion models, there are several major uncertainties related to the timescale of collapse, the relative importance of different processes for preventing fragmentation in massive cores, and the nature of disks and outflows. I end by discussing some recent observational results that are helping to improve our understanding of these processes.
Star Formation Thresholds: The View from Inside the Galaxy
Authors: Di Francesco James
Published: September 2016

We explore the relationship between the total gas surface density and star formation rate surface density, a.k.a., the “Kennicutt-Schmidt relation,” in a Galactic context. Specifically, we probe the origins of thresholds in the behaviour of the K-S relation at 10 M⊙ pc−2 and 100-200 M⊙ pc−2 using images from the Herschel Hi-GAL and Gould Belt surveys. In both cases, pervasive filamentary structures are seen, possibly due to turbulent motions. The Hi-GAL image supports the view that at ~10 M⊙ pc−2 gas becomes molecular, leading to the formation of clouds that harbour star formation. The GBS images suggest the 100-200 M⊙ pc−2 threshold originates from the nature of filaments being stable until a critical column density of ~160 M⊙ pc−2 is reached. Therefore, the transition between non-star-forming and star-forming gas in clouds (and galaxies) may be set universally by the dynamical properties of filaments.
Gas flows in galactic nuclei: observational constraints on BH-galaxy coevolution
Authors: García-Burillo Santiago
Published: September 2016

Galaxy nuclei are a unique laboratory to study gas flows. Their high-resolution imaging in galactic nuclei are instrumental in the study of the fueling and feedback of star formation and nuclear activity in nearby galaxies. Several fueling mechanisms can now be confronted in detail with observations done with state-of-the-art interferometers. Furthermore, the study of gas flows in galactic nuclei can probe the feedback of activity on the interstellar medium of galaxies. Feedback action from star formation and AGN activity is invoked to prevent galaxies from becoming overly massive, but also to explain scaling laws like black hole (BH)-bulge mass correlations and the bimodal color distribution of galaxies. This close relationship between galaxies and their central supermassive BH can be described as co-evolution. There is mounting observational evidence for the existence of gas outflows in different populations of starbursts and active galaxies, a manifestation of the feedback of activity. We summarize the main results recently obtained from the observation of galactic inflows and outflows in a variety of active galaxies with current millimeter interferometers such as ALMA or the IRAM array.
High resolution ALMA observations of dense molecular medium in the central regions of active galaxies
Authors: Kohno Kotaro , Ando Ryo , Taniguchi Akio , Izumi Takuma , Tosaki Tomoka
Published: September 2016

In the central regions of active galaxies, dense molecular medium are exposed to various types of radiation and energy injections, such as UV, X-ray, cosmic ray, and shock dissipation. With the rapid progress of chemical models and implementation of new-generation mm/submm interferometry, we are now able to use molecules as powerful diagnostics of the physical and chemical processes in galaxies. Here we give a brief overview on the recent ALMA results to demonstrate how molecules can reveal underlying physical and chemical processes in galaxies. First, new detections of Galactic molecular absorption systems with elevated HCO/H13CO+column density ratios are reported, indicating that these molecular media are irradiated by intense UV fields. Second, we discuss the spatial distributions of various types of shock tracers including HNCO, CH3OH and SiO in NGC 253 and NGC 1068. Lastly, we provide an overview of proposed diagnostic methods of nuclear energy sources using ALMA, with an emphasis on the synergy with sensitive mid-infrared spectroscopy, which will be implemented by JWST and SPICA to disentangle the complex nature of heavily obscured galaxies across the cosmic time.
Interactions and star formation
Authors: Knapen Johan H. , Cisternas Mauricio , Querejeta Miguel
Published: September 2016

We investigate the influence of interactions on the star formation by studying a sample of almost 1500 of the nearest galaxies, all within a distance of ~45 Mpc. We define the massive star formation rate (SFR), as measured from far-IR emission, and the specific star formation rate (SSFR), which is the former quantity normalized by the stellar mass of the galaxy, and explore their distribution with morphological type and with stellar mass. We then calculate the relative enhancement of these quantities for each galaxy by normalizing them by the median SFR and SSFR values of individual control populations of similar non-interacting galaxies. We find that both SFR and SSFR are enhanced in interacting galaxies, and more so as the degree of interaction is higher. The increase is, however, moderate, reaching a maximum of a factor of 1.9 for the highest degree of interaction (mergers). The SFR and SSFR are enhanced statistically in the population, but in most individual interacting galaxies they are not enhanced at all. We discuss how those galaxies with the largest SFR and/or SSFR enhancement can be defined as starbursts. We argue that this study, based on a representative sample of nearby galaxies, should be used to place constraints on studies based on samples of galaxies at larger distances.
The Evolution of Gas Content and Star Formation from z=3 to z=0
Authors: Combes Francoise ,   the PHIBSS collaboration
Published: September 2016

The cosmic star formation rate density first increases with time towards a pronounced peak 10 Gyrs ago (or z=1-2) and then slows down, dropping by more than a factor 10 since z=1. The processes at the origin of the star formation quenching are not yet well identified: either the gas is expelled by supernovae and AGN feedback, or prevented to inflow. Morphological transformation or environment effects are also invoked. Recent IRAM/NOEMA and ALMA results are reviewed about the molecular content of galaxies and its dynamics, as a function of redshift. Along the main sequence of massive star forming galaxies, the gas fraction was higher in the past (up to 80%), and galaxy disks were more unstable and more turbulent. The star formation efficiency increases with redshift, or equivalently the depletion time decreases, whatever the position of galaxies, either on the main sequence or above. Attempts have been made to determine the cosmic evolution of the H2 density, but deeper ALMA observations are needed to effectively compare with models.
On the Variation of Gas Depletion Time
Authors: Utomo D. , Blitz L. , Bolatto A. , Wong T. , Leroy A. , Vogel S. ,   EDGE-CALIFA Collaboration
Published: September 2016

We present an updated status of the EDGE project, which is a survey of 125 local galaxies in the 12CO(1−0) and 13CO(1−0) lines. We combine the molecular data of the EDGE survey with the stellar and ionized gas maps of the CALIFA survey to give a comprehensive view of the dependence of the star formation efficiency, or equivalently, the molecular gas depletion time, on various local environments, such as the stellar surface density, metallicity, and radius from the galaxy center. This study will provide insight into the parameters that drive the star formation efficiency in galaxies at z ~ 0.
Evaporation of grain-surface species by shock waves onto a forming protoplanetary disk
Authors: Aikawa Yuri , Aota Takuhiro , Inoue Tsuyoshi
Published: September 2016

We investigate the sputtering and thermal desorption of various grain-surface species in one dimensional steady-state shock models motivated by the recent detection of SO emission towards class 0-I protostars. We find that the thermal desorption is more efficient at higher densities, while the efficiency of sputtering is independent of density. SO is completely desorbed, if the accretion velocity is higher than ~ 2 km s−1 and ~ 4 km s−1, with the pre-shock density of 109 cm−3 and 108 cm−3, respectively. The column density of warm post-shock gas is found to be N ~ 1021 cm−2. If the abundance of SO ice is ~ 10−7 relative to hydrogen in the pre-shock material, SO emission around L1527 can be explained by the sublimation at the accretion shock.
Connecting the Interstellar Gas and Dust Properties in Distant Galaxies Using Quasar Absorption Systems
Authors: Aller Monique C. , Kulkarni Varsha P. , York Donald G. , Welty Daniel E. , Vladilo Giovanni , Som Debopam , Lackey Kyle , Dwek Eli , Beiranvand Nassim , Morrison Sean
Published: September 2016

Gas and dust grains are fundamental components of the interstellar medium and significantly impact many of the physical processes driving galaxy evolution, such as star-formation, and the heating, cooling, and ionization of the interstellar material. Quasar absorption systems (QASs), which trace intervening galaxies along the sightlines to luminous quasars, provide a valuable tool to directly study the properties of the interstellar gas and dust in distant, normal galaxies. We have established the presence of silicate dust grains in at least some gas-rich QASs, and find that they exist at higher optical depths than expected for diffuse gas in the Milky Way. Differences in the absorption feature shapes additionally suggest variations in the silicate dust grain properties, such as in the level of grain crystallinity, from system-to-system. We present results from a study of the gas and dust properties of QASs with adequate archival IR data to probe the silicate dust grain properties. We discuss our measurements of the strengths of the 10 and 18 μm silicate dust absorption features in the QASs, and constraints on the grain properties (e.g., composition, shape, crystallinity) based on fitted silicate profile templates. We investigate correlations between silicate dust abundance, reddening, and gas metallicity, which will yield valuable insights into the history of star formation and chemical enrichment in galaxies.
ThrUMMS: A New View of the Molecular Milky Way
Authors: Barnes Peter , Muller Erik , Luong Quang Nguyen , Nguyen Hans
Published: September 2016

We present the Three-mm Ultimate Mopra Milky Way Survey, a new mm-wave molecular-line mapping survey of the southern Galactic Plane, and its first data releases and science results. ThrUMMS maps a 60° × 2° sector of our Galaxy's fourth quadrant, using a combination of fast mapping techniques with the Mopra radio telescope, simultaneously in the J = 1→0 lines of 12CO, 13CO, C18O, and CN near 112 GHz, at 1′.2 and 0.3 km s−1 resolution, with 1.2 K/ch sensitivity for 12CO and 0.7 K/ch for the other transitions. The calibrated data cubes from these observations are made freely available to the community on the ThrUMMS website, http://www.astro.ufl.edu/thrumms, after processing through our pipeline. Here, we summarise the first science results, on global variations in the iso-CO line ratios and on a detailed multiwavelength study of the GMCs near l=333°.
Extended Carbon Emission in the Galaxy: Dark Gas along the G328 Sightline
Authors: Burton M. , Ashley M. , Braiding C. , Freeman M. , Kulesa C. , Wolfire M. , Hollenbach D. , Rowell G. , Lau J.
Published: September 2016

We present spectral data cubes of the [CI] 809 GHz, 12CO 115 GHz, 13CO 110 GHz and HI 1.4 GHz line emission from a ~1° region along the l = 328° (G328) sightline in the Galactic Plane. The [CI] data comes from the High Elevation Antarctic Terahertz telescope at Ridge A on the summit of the Antarctic plateau, where the extremely low levels of precipitable water vapour open atmospheric windows for THz observations. The CO data comes from the Southern Galactic Plane Survey being conducted with the Mopra telescope. Emission arises principally from gas in three spiral arm crossings along the sight line. The distribution of the emission in the CO and [CI] lines is found to be similar, with the [CI] slightly more extended, and both are enveloped in extensive HI. Spectral line ratios are similar across the entire extent of the Galaxy. However, towards the edges of the molecular clouds the [CI]/13CO and 12CO/13CO line ratios rise by ~ 50%, and the [CI]/Hi ratio falls by ~ 10%. We attribute this to sightlines passing predominantly through the surfaces of photodissociation regions (PDRs), where the carbon is found mainly as C or C+ rather than CO, while the gas is mostly molecular. This is the signature of dark molecular gas.
SFR bulge-to-disk ratios from the CALIFA IFS nearby galaxies survey
Authors: Catalán-Torrecilla C. , de Paz A. Gil , Castillo-Morales A. , Méndez-Abreu J. , Iglesias-Páramo J. , Madore B.F. , Pascual S. , Ruiz-Lara T. , de Lorenzo-Cáceres A. , Sánchez-Menguiano L. , Sánchez S. ,   CALIFA Collaboration
Published: September 2016

Our aim is to study the Star Formation Rate (SFR) by galaxy components such as bulges, bars and disks in a representative sample of nearby galaxies. A 2-dimensional (2D) photometric decomposition approach (GASP2D) is used to obtain these components. The availability of IFS data for the CALIFA galaxies makes possible to go one step further as we can apply the previous decompositions over 3D datacubes to disentangle the spatial distribution of the SFR over different components free from the limitations associated to narrow-band imaging.
The feedback of Herbig Ae/Be stars
Authors: Zhang Chengpeng , Wu Yuefang , Yuan Jing-Hua , Liu Tie
Published: September 2016

To study the molecular environment and feedback of Herbig Ae/Be (HAB) stars, We mapped four HAB stars' nearby region with CO (1-0) and its isotopes by the 13.7m millimeter telescope of Purple Mountain Observatory. The results show that new stars are forming in the nearby molecular cores and HAB stars give them an extra pressure. On the other hand, HAB stars are the main heat source of their surrounding gas.