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We present ALMA 3 mm molecular line and continuum observations with a resolution of ~3.5" towards five first hydrostatic core (FHSC) candidates (L1451-mm, Per-bolo 58, Per-bolo 45, L1448-IRS2E and Cha-MMS1). Our goal is to characterize their envelopes and identify the most promising sources that could be bona fide FHSCs. We identify two candidates which are consistent with an extremely young evolutionary state (L1451-mm and Cha-MMS1), with L1451-mm being the most promising FHSC candidate. Although our envelope observations cannot rule out Cha-MMS1 as a FHSC yet, the properties of its CO outflow and SED published in recent studies are in better agreement with the predictions for a young protostar. For the remaining three sources, our observations favor a prestellar nature for Per-bolo 45 and rule out the rest as FHSC candidates. Per-bolo 58 is fully consistent with being a Class 0, while L1448 IRS2E shows no emission of high-density tracers (NH2D and N2H+) at the location of the previously identified compact continuum source, which is also undetected in our observations. Thus we argue that there is no embedded source at the presumptive location of the FHSC candidate L1448 IRS2E. We propose instead, that what was thought to be emission from the presumed L1448 IRS2E outflow corresponds to outflow emission from a nearby Class 0 system, deflected by the dense ambient material. We compare the properties of the FHSC candidates studied in this work and the literature, which shows that L1451-mm appears as possibly the youngest source with a confirmed outflow., 26 pages, 14 figures. Accepted for publication in MNRAS

The mass distribution of dense cores is a potential key to understand the process of star formation. Applying dendrogram analysis to the CARMA-NRO Orion C$^{18}$O ($J$=1--0) data, we identify 2342 dense cores, about 22 \% of which have virial ratios smaller than 2, and can be classified as gravitationally bound cores. The derived core mass function (CMF) for bound starless cores which are not associate with protostars has a slope similar to Salpeter's initial mass function (IMF) for the mass range above 1 $M_\odot$, with a peak at $\sim$ 0.1 $M_\odot$. We divide the cloud into four parts based on the declination, OMC-1/2/3, OMC-4/5, L1641N/V380 Ori, and L1641C, and derive the CMFs in these regions. We find that starless cores with masses greater than 10 $M_\odot$ exist only in OMC-1/2/3, whereas the CMFs in OMC-4/5, L1641N, and L1641C are truncated at around 5--10 $M_\odot$. From the number ratio of bound starless cores and Class II objects in each subregion, the lifetime of bound starless cores is estimated to be 5--30 free-fall times, consistent with previous studies for other regions. In addition, we discuss core growth by mass accretion from the surrounding cloud material to explain the coincidence of peak masses between IMFs and CMFs. The mass accretion rate required for doubling the core mass within a core lifetime is larger than that of Bondi-Hoyle accretion by a factor of order 2. This implies that more dynamical accretion processes are required to grow cores., Comment: 58 pages, 33 figures, 21 tables, accepted by ApJS

We adopt the deep learning method CASI-3D (Convolutional Approach to Structure Identification-3D) to systemically identify protostellar outflows in 12CO and 13CO observations of the nearby molecular clouds, Ophiuchus, Taurus, Perseus and Orion. The total outflow masses are 267 Msun, 795 Msun, 1305 Msun and 6332 Msun for Ophiuchus, Taurus, Perseus and Orion, respectively. We show the outflow mass in each cloud is linearly proportional to the total number of young stellar objects. The estimated total 3D deprojected outflow energies are 9e45 ergs, 6e46 ergs, 1.2e47 ergs and 6e47 ergs for Ophiuchus, Taurus, Perseus and Orion, respectively. The energy associated with outflows is sufficient to offset turbulent dissipation at the current epoch for all four clouds. All clouds also exhibit a break point in the spatial power spectrum of the outflow prediction map, which likely corresponds to the typical outflow mass and energy injection scale., ApJ Accepted

In democratic societies, elections can act as a referendum on politicians’ counterterror policy. At the same time, counterterror policy is conducted under conditions of asymmetric information becau...

Molecular dynamics (MD) simulations of the zwitterionic surfactant octyl phosphocholine (OPC) in water have been performed with two force fields, both using the TraPPE united-atom alkane parameters for tailgroup-tailgroup interactions but with tailgroup-water interactions adjusted to reproduce hydration free energies for two different water models (SPC and TIP4P-2005). Micelle size distributions from a number of trajectories were analyzed using the PEACH (Partition-Enabled Analysis of Cluster Histograms) method to yield free energies of aggregation for premicelles and micelles over the full range from 2 to over 40 molecules. The dependence of free energy on aggregation number was consistent with the functional form derived from the “quasi-droplet” model of micellization. Free energies of aggregation were used to calculate concentration-dependent micelle size distributions, from which critical micelle concentrations (cmc's) could be inferred. The cmc values derived from PEACH free energies for the SPC and TIP4P-2005 models were 40% and 27% higher respectively than the experimentally reported value of 114 mM. In systems with enough monomers to form multiple micelles, the micelles tended to stick together, complicating the analysis. Micelle size distributions were used to weight small-angle X-ray scattering (SAXS) form factors derived from micelle structures, generating a composite form factor reflecting the polydispersity of aggregate sizes with contributions in the range from 20 to 45 monomers. The composite scattering profile was quite similar to that of the mass-weighted average micelle size, suggesting that SAXS profiles for small micelles can be adequately fit using a single typical micelle even in the presence of significant polydispersity.

This paper derives a dynamic path of ongoing terror attacks as a function of terrorists’ capacity and a target government’s counterterror capacity. The analysis provides several novel insights and characterizations. First, the effect of counterterror policy is limited. Second, proactive counterterror policy affects the depreciation (fatigue) of terrorists’ capacity, and defensive counterterror policy limits the worst-case scenario. Third, fluctuations in the time path of attacks are a function of terrorists’ time preferences and adjustment costs of changing tactics, which are policy invariant. Indeed, in our model, the oscillations of terror attacks occur irrespective of the government’s counterterror stance. Fourth, collective action inefficiencies associated with the underprovision of proactive counterterror policies and overprovision of defensive ones are further exacerbated by our finding that proactive counterterror policy is the more effective of the two. Hence, the more effective policy is underprovided.

We present the first results from a CARMA high-resolution $^{12}$CO(1-0), $^{13}$CO(1-0), and C$^{18}$O(1-0) molecular line survey of the North America and Pelican (NAP) Nebulae. CARMA observations have been combined with single-dish data from the Purple Mountain 13.7m telescope to add short spacings and produce high-dynamic-range images. We find that the molecular gas is predominantly shaped by the W80 HII bubble that is driven by an O star. Several bright rims are probably remnant molecular clouds heated and stripped by the massive star. Matching these rims in molecular lines and optical images, we construct a model of the three-dimensional structure of the NAP complex. Two groups of molecular clumps/filaments are on the near side of the bubble, one being pushed toward us, whereas the other is moving toward the bubble. Another group is on the far side of the bubble and moving away. The young stellar objects in the Gulf region reside in three different clusters, each hosted by a cloud from one of the three molecular clump groups. Although all gas content in the NAP is impacted by feedback from the central O star, some regions show no signs of star formation, while other areas clearly exhibit star formation activity. Other molecular gas being carved by feedback includes the cometary structures in the Pelican Head region and the boomerang features at the boundary of the Gulf region. The results show that the NAP complex is an ideal place for the study of feedback effects on star formation., accepted by AJ

We study star formation in the Center Ridge 1 (CR1) clump in the Vela C giant molecular cloud, selected as a high column density region that shows the lowest level of dust continuum polarization angle dispersion, likely indicating that the magnetic field is relatively strong. We observe the source with the ALMA 7m-array at 1.05~mm and 1.3~mm wavelengths, which enable measurements of dust temperature, core mass and astrochemical deuteration. A relatively modest number of eleven dense cores are identified via their dust continuum emission, with masses spanning from 0.17 to 6.7 Msun. Overall CR1 has a relatively low compact dense gas fraction compared with other typical clouds with similar column densities, which may be a result of the strong magnetic field and/or the very early evolutionary stage of this region. The deuteration ratios, Dfrac, of the cores, measured with N2H+(3-2) and N2D+(3-2) lines, span from 0.011 to 0.85, with the latter being one of the highest values yet detected. The level of deuteration appears to decrease with evolution from prestellar to protostellar phase. A linear filament, running approximately parallel with the large scale magnetic field orientation, is seen connecting the two most massive cores, each having CO bipolar outflows aligned orthogonally to the filament. The filament contains the most deuterated core, likely to be prestellar and located midway between the protostars. The observations permit measurement of the full deuteration structure of the filament along its length, which we present. We also discuss the kinematics and dynamics of this structure, as well as of the dense core population., 25 pages, 17 figures, accepted by ApJ

A sample of 1.3 mm continuum cores in the Dragon infrared dark cloud (also known as G28.37+0.07 or G28.34+0.06) is analyzed statistically. Based on their association with molecular outflows, the sample is divided into protostellar and starless cores. Statistical tests suggest that the protostellar cores are more massive than the starless cores, even after temperature and opacity biases are accounted for. We suggest that the mass difference indicates core mass growth since their formation. The mass growth implies that massive star formation may not have to start with massive prestellar cores, depending on the core mass growth rate. Its impact on the relation between core mass function and stellar initial mass function is to be further explored., Comment: accepted by ApJ

Dynamical studies of dense structures within molecular clouds often conclude that the most massive clumps contain too little kinetic energy for virial equilibrium, unless they are magnetized to an unexpected degree. This raises questions about how such a state might arise, and how it might persist long enough to represent the population of massive clumps. In an effort to re-examine the origins of this conclusion, we use ammonia line data from the Green Bank Ammonia Survey and Planck-calibrated dust emission data from Herschel to estimate the masses and kinetic and gravitational energies for dense clumps in the Gould Belt clouds. We show that several types of systematic error can enhance the appearance of low kinetic-to-gravitational energy ratios: insufficient removal of foreground and background material; ignoring the kinetic energy associated with velocity differences across a resolved cloud; and over-correcting for stratification when evaluating the gravitational energy. Using an analysis designed to avoid these errors, we find that the most massive Gould Belt clumps harbor virial motions, rather than sub-virial ones. As a byproduct, we present a catalog of masses, energies, and virial energy ratios for 85 Gould Belt clumps., Comment: Submitted to ApJ

Takemura, H., et al., Applying dendrogram analysis to the CARMA-NRO C18O (J = 1-0) data having an angular resolution of ∼8″, we identified 692 dense cores in the Orion Nebula Cluster region. Using this core sample, we compare the core and initial stellar mass functions in the same area to quantify the step from cores to stars. About 22% of the identified cores are gravitationally bound. The derived core mass function (CMF) for starless cores has a slope similar to Salpeter's stellar initial mass function (IMF) for the mass range above 1 M o˙, consistent with previous studies. Our CMF has a peak at a subsolar mass of ∼0.1 M o˙, which is comparable to the peak mass of the IMF derived in the same area. We also find that the current star formation rate is consistent with the picture in which stars are born only from self-gravitating starless cores. However, the cores must gain additional gas from the surroundings to reproduce the current IMF (e.g., its slope and peak mass), because the core mass cannot be accreted onto the star with 100% efficiency. Thus, the mass accretion from the surroundings may play a crucial role in determining the final stellar masses of stars., P.S. was partially supported by a Grant-in-Aid for Scientific Research (KAKENHI Number 18H01259) of Japan Society for the Promotion of Science (JSPS). R.S.K. acknowledges financial support from the DFG via the collaborative research center (SFB 881, Project-ID 138713538) “The Milky Way System” (subprojects A1, B1, B2, and B8). He is also thankful for subsidies from the Heidelberg Cluster of Excellence STRUCTURES in the framework of Germanyʼs Excellence Strategy (grant EXC-2181/1-390900948) and for funding from the European Research Council (ERC) via the ERC Synergy Grant ECOGAL (grant 855130). P.P. acknowledges support by the Spanish MINECO under project AYA2017- 88754-P, and financial support from the State Agency for Research of the Spanish Ministry of Science and Innovation through the “Unit of Excellence María de Maeztu 2020-2023” award to the Institute of Cosmos Sciences (CEX2019-000918-M). V.O., A.S.M., and P.S. were supported by the Collaborative Research Centre 956, subprojects C1, A6, and C3, funded by the Deutsche Forschungsgemeinschaft (DFG), project ID 184018867. T.G.S.P. gratefully acknowledges support by the National Science Foundation under grant No. AST-2009842. J.E.P. acknowledges the support by the Max Planck Society. We thank the anonymous referee for many useful comments that have improved the presentation

INTRODUCCION: En la terapeutica endodontica el exito depende no solo de la instrumentacion del sistema de conductos sino tambien de una adecuada limpieza y desinfeccion de este. La desinfeccion se logra a traves de la irrigacion del conducto y el irrigante mas utilizado es el hipoclorito de sodio (NaOCl), ya que presenta propiedades bactericida y bacteriostatica, baja tension superficial, pH alcalino, pero fundamentalmente porque es la unica solucion irrigante con capacidad para disolver el tejido organico. Se presenta en diferentes concentraciones de 0.5% al 6%, y diferentes marcas comerciales de uso odontologico y domestico. OBJETIVO: Comparar 2 formas comerciales de NaOCl para disolver la materia organica en diferentes tiempos de exposicion. MATERIALES Y METODOS: Se prepararon 20 trozos de tejido muscular bovino, los cuales fueron sumergidos durante 5, 10, 15, 20 minutos en una solucion de NaOCl. La muestra se dividio en 2 grupos (n=10) Grupo 1: NaOCl al 5.5% de uso odontologico y Grupo 2: NaOCl de uso domestico al 5.5%. Cada trozo de carne fue pesado inicialmente en una balanza electronica (Ohyo MP-300) y se registro en una tabla Excel. Posteriormente, se sumergio en 10ml. de NaOCl durante 5 minutos. El mismo se retiro del NaOCl, y se sumergio en solucion fisiologica para eliminar e inactivar la solucion de irrigacion. Se seco con papel absorbente y se peso en la balanza electronica (Ohyo MP-300). Este procedimiento se repitio a los 10, 15 y 20 minutos, renovando la solucion de irrigacion para simular las condiciones clinicas y evitar saturacion. Los datos recogidos fueron registrados y evaluados estadisticamente mediante la prueba de analisis con la variable de un factor (ANOVA). RESULTADOS: El porcentaje de disolucion de materia organica con NaOCl de uso odontologico fue similar al de uso domestico a los 5, 10 y 15 minutos. A los 20 minutos con Tedequim se disolvio el 63,8% de materia organica y con Ayudin el 69%. Las diferencias no resultaron estadisticamente significativas CONCLUSIONES: Bajo las condiciones de este estudio se pudo concluir que tanto el NaOCl Tedequim como el Ayudin disolvieron la materia organica de manera similar en el tiempo, siendo el de uso domestico de mas facil acceso y menor costo.

The INBUILD trial investigated the efficacy and safety of nintedanib versus placebo in patients with progressive fibrosing interstitial lung diseases (ILDs) other than idiopathic pulmonary fibrosis (IPF). We aimed to establish the effects of nintedanib in subgroups based on ILD diagnosis., info:eu-repo/semantics/published

We identify 45 protostellar outflows in CO maps of the Orion A giant molecular cloud from the CARMA-NRO Orion survey. Our sample includes 11 newly detected outflows. We measure the mass and energetics of the outflows, including material at low-velocities by correcting for cloud contributions. The total momentum and kinetic energy injection rates of outflows is comparable to the turbulent dissipation rate of the cloud. We also compare the outflow position angles to the orientation of C$^{18}$O filaments. We find that the full sample of outflows is consistent with being randomly oriented with respect to the filaments. A subsample of the most reliable measurements shows a moderately perpendicular outflow-filament alignment which may reflect accretion of mass across filaments and onto the protostellar cores., 22 pages, 11 figures in main text, 47 additional figures in appendices. Accepted to ApJ

Terrorist attacks are regarded as low-probability, highly consequential events. What, exactly, are the significant effects of terrorism? This paper presents a cross-sectional depiction of the death and injury profiles for nine of the most violent terrorism tactics: six types of bombings, mass shootings, combined shootings and explosions, and intentional vehicular assaults. By constructing a composite injury and death profile for each tactic under study, terrorist incidents can be ranked in terms of the number of disability adjusted lives lost and disability adjusted life years lost. In addition, the human consequences of terrorism as a whole (on an annual basis) are placed in context relative to the global burden of disease and counterterror expenditures.

Strategic monitoring occurs in myriad situations such as principal–agent relationships, law enforcement and treaty verification. Such situations are generally known as enforcement or inspection games, with the focus largely being on the (counterintuitive) properties of their associated mixed strategy Nash equilibrium. This article instead characterizes the cooperative resolution of the mixed motives of the players involved. It does so through an illustrative decomposition of the enforcement/inspection game into its cooperative and competitive constituent parts. The results are interpreted within an efficiency wage context and the distribution of the saved monitoring costs that cooperation engenders.