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We present the first 3D radiation-hydrodynamic simulations of the formation of planetary nebulae (PNe) emerging from 3D spiral patterns. We use the GUACHO code to create 3D spiral structures as a consequence of the distortions on the geometry of the intrinsically isotropic wind of an asymptotic giant branch (AGB) star produced by a companion star in a circular orbit. We found that the orbital period of the binary producing the 3D spiral pattern has consequences on the formation and shaping of the PN itself. Stellar systems with longer period create less entwined 3D spirals, producing PNe with rounder inner cavities, and prevent the expansion of jet towards the polar directions. The spiral fitting procedure used in the literature to predict the binary's orbital period may be misleading in the case of proto-PNe and PNe as spiral patterns are diluted by their own thermal expansion down to the average AGB density profile within a few hundred years and are further disrupted by the action of jets. By adopting a phase of jet ejections between the AGB and post-AGB stages, we are able to recover the morphologies of proto-PNe and PNe that exhibit ring-like structures in their halos., 12 pages, 12 figures, 1 table; Accepted to MNRAS

e present the first 3D radiation-hydrodynamic simulations on the formation and evolution of born-again planetary nebulae (PNe), with particular emphasis to the case of HuBi 1, the inside-out PN. We use the extensively tested GUACHO code to simulate the formation of HuBi 1 adopting mass-loss and stellar wind terminal velocity estimates obtained from observations presented by our group. We found that, if the inner shell of HuBi 1 was formed by an explosive very late thermal pulse (VLTP) ejecting material with velocities of ∼300 km s−1, the age of this structure is consistent with that of ≃200 yr derived from multi-epoch narrow-band imaging. Our simulations predict that, as a consequence of the dramatic reduction of the stellar wind velocity and photon ionizing flux during the VLTP, the velocity and pressure structure of the outer H-rich nebula are affected creating turbulent ionized structures surrounding the inner shell. These are indeed detected in Gran Telescopio Canarias MEGARA optical observations. Furthermore, we demonstrate that the current relatively low ionizing photon flux from the central star of HuBi 1 is not able to completely ionize the inner shell, which favours previous suggestions that its excitation is dominated by shocks. Our simulations suggest that the kinetic energy of the H-poor ejecta of HuBi 1 is at least 30 times that of the clumps and filaments in the evolved born-again PNe A 30 and A 78, making it a truly unique VLTP event. © 2021 The Author(s)., JAT thanks funding by Fundación Marcos Moshinsky (Mexico) and the Direcciónn General de Asuntos del Personal Académico (DGAPA) of the Universidad Nacional Autónoma de México (UNAM) project IA100720. VL gratefully acknowledges support from the CONACYT Research Fellowship program. BMM and MAG acknowledge support of the Spanish Ministerio de Ciencia, Innovación y Universidades (MCIU) grant PGC2018-102184-B-I00. AE acknowledges support from DGAPA-PAPIIT (UNAM) grant IN 109518. This work has made extensive use of NASA’s Astrophysics Data System., With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709.

We study self-gravitating, hydrostatic spheres with a polytropic equation of state P ∝ ρ^γ (where γ is the specific heat ratio of the gas), considering structures with γ ≈ 1 as a model for molecular cloud cores with small departures from isother- mality. We derive the properties (i.e., mass, radius and center to edge density ratio) as a function of γ for the maximal stable sphere through an application of “Bonnor’s stability criterion”. We find that in the γ = 1 → 4/3 range the mass of the maximal sphere (for a given central temperature) is almost constant, and that its radius and center to edge density ratio are growing functions of γ. We therefore have maximal stable, self-gravitating spheres with similar masses, but with increasing center to edge density contrasts for increasing departures from isothermality.

The dynamical friction timescale of massive globular clusters (GCs) in the inner regions of cuspy dark haloes in dwarf spheroidal (dSph) galaxies can be much shorter than the Hubble time. This implies that a small fraction of the GCs is expected to be caught close to the centre of these galaxies. We compare the radial distribution of GCs predicted in simple Monte Carlo models with that of a sample of $38$ spectroscopically confirmed GCs plus 17 GC candidates, associated mainly to low-luminosity dSph galaxies. If dark matter haloes follow an NFW profile, the observed number of off-center GCs at projected distances less than one half the galaxy effective radius is significantly higher than models predict. This timing problem can be viewed as a fine-tuning of the starting GC distances. As a result of the short sinking timescale for GCs in the central regions, the radial distribution of GCs is expected to evolve significantly during the next 1-2 Gyr. However, dark matter haloes with cores of size comparable to the galaxy effective radii can lead to a slow orbital in-spiral of GCs in the central regions of these galaxies, providing a simple solution to the timing problem. We also examine any indication of mass segregation in the summed distribution of our sample of GCs., 18 pages, 20 figures, accepted for publication in MNRAS

This book provides a comprehensive overview of the future scenarios of climate change and management concerns associatedwith climate change impacts on the blue economy of European islands and outermost regions. The publication collectsmajor findings of the Soclimpact project’s research outcomes, aiming to raise social awareness among policy-makers andindustry about climate change consequences at local level, and provide knowledge based information in support policy design,from local to national level. This comprehensive book will also assist students, scholars and practitioners to understand,conceptualize and effectively and responsibly manage climate change information and applied research. This book providesinvaluable material for Blue Growth Management, theory and application, at all levels. This first edition includes up-to-datedata, statistics, references, case material and figures of the 12 islands case studies. ¨Downscaling climate change impacts,socio-economic implications and alternative adaptation pathways for Islands and Outermost Regions¨ is a must-read book,given the accessible style and breadth and depth with which the topic is dealt. The book is an up-to-date synthesis of keyknowledge on this area, written by a multidisciplinary group of experts on climate and economic modelling, and policy design.

Recent analyses of Gaia data have provided direct evidence that most young stellar clusters are in a state of expansion, with velocities of the order of ~0.5 km/s. Traditionally, expanding young clusters have been pictured as entities that became unbound due to the lack of gravitational binding once the gas from the parental cloud that formed the cluster has been expelled by the stellar radiation of the massive stars in the cluster. In the present contribution, we used radiation-magnetohydrodynamic numerical simulations of molecular cloud formation and evolution to understand how stellar clusters form and disperse. We found that the ionising feedback from the newborn massive stars expels the gas from the collapse centre, flipping-up the gravitational potential as a consequence of the mass removal from the inside-out. Since neither the parental clouds nor the formed shells are distributed symmetrically around the HII region, net forces pulling out the stars are present, accelerating them towards the edges of the cavity. We call this mechanism ``gravitational feedback", in which the gravity from the expelled gas appears to be the crucial mechanism producing unbound clusters that expand away from their formation centre in an accelerated way in young stellar clusters. This mechanism naturally explains the "Hubble flow-like" expansion observed in several young clusters., Comment: Accepted for publication in MNRAS

The nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) controls the expression of genes involved in the regulation of lipid and glucose metabolism, cell proliferation/differentiation as well as inflammatory pathways. Pivotal studies in human sebocytes and isolated sebaceous glands have raised the interesting possibility that compounds acting on PPARγ can modulate sebaceous lipids and inflammation and, as such, may be useful in the treatment of acne. To investigate the role of this receptor in the regulation of lipid synthesis, proliferation and inflammation, we used the SZ95 sebaceous gland cell line stimulated with insulin. In sebocytes, insulin signaling activated the phosphatidylinositide 3-kinase-Akt (PI3K/Akt) and mammalian target of rapamycin (mTOR) pathways, which, in turn, induced high protein/lipid synthesis, increased cell growth and proliferation as well as inflammation. As regards lipogenesis, insulin initially stimulated the formation of unsaturated lipids and then the neosynthesis of lipids. The results showed, that the modulation of PPARγ, counteracted the insulin-induced altered lipogenesis, evident through a decrease in gene expression of key enzymes responsible for the synthesis of fatty acids, and through a reduction of lipid species synthesis analyzed by Oil/Nile Red staining and GC-MS. PPARγ modulation also regulated the insulin-induced proliferation, inhibiting the cell cycle progression and p21WAF1/CIP1 (p21) protein reduction. Moreover, the expression of inflammatory cytokines, induced by insulin or lipopolysaccharide (LPS), was down-modulated. In PPARγ-deficient cells or in the presence of GW9662 antagonist, all these observed effects were abolished, indicating that PPARγ activation plays a role in regulating alteration of lipogenesis, cell proliferation and inflammatory signaling. We demonstrated that selective modulation of PPARγ activity is likely to represent a therapeutic strategy for the treatment of acne.

Dwarf spheroidal galaxies (dSph) orbiting the Milky Way are complex objects often with complicated star formation histories and internal dynamics. In this work, we search for stellar substructures in four of the classical dSph satellites of the Milky Way: Sextans, Carina, Leo I, and Leo II. We apply two methods to search for stellar substructure: the minimum spanning tree method, which helps us to find and quantify spatially connected structures, and the "brute-force" method, which is able to find elongated stellar substructures. We detected the previously known substructure in Sextans, and also found a new stellar substructure within Sextans. Furthermore, we identified a new stellar substructure close to the core radius of the Carina dwarf galaxy. We report a detection of one substructure in Leo I and two in Leo II, but we note that we are dealing with a low number of stars in the samples used. Such old stellar substructures in dSph galaxies could help us to shed light on the nature of the dark matter halos, within which such structures form, evolve, and survive., Comment: Accepted for publication in ApJ, 13 pages, 6 figures

Background:TNF inhibitors have been largely demonstrated to be effective and reasonably safe for the treatment of psoriatic arthritis (PsA). Current EULAR guidelines recommend the use of an anti-TNF as first choice treatment in patients with PsA for whom a synthetic DMARD (usually methotrexate or leflunomide) is not efficacious or not well tolerated [1]. In a scenario where biologic treatments are easily available, and the treat to target strategy is widely accepted, a complete disease remission or at least a minimal disease activity are considered realistic goals to be achieved in a growing proportion of patients [2]. However, there remains very little research regarding anti-TNF discontinuation in patients who achieved a complete remission [3-5].Objectives:The primary aim of this study was to measure the disease-free interval after anti-TNF discontinuation, secondary it was investigated whether the use of Power Doppler Ultrasound (PDUS) and Contrast Enhanced Ultrasound (CEUS) could improve the diagnostic accuracy in the recognition of the relapse. Finally, we wanted to characterize the clinical features of the disease recurrence.Methods:From June 2018, 35 patients with PsA (27 males and 8 female) treated with anti-TNF, in stable remission were prospectively monitored for 1 year after treatment discontinuation. Remission was defined as documented absence of clinical and ultrasonographic signs of arthritis or enthesitis. Complete rheumatological and dermatological examinations were performed in all participants, at baseline and every 8-12 weeks: American College of Rheumatology (ACR) 66-68 joint count; Psoriasis Area Severity Index (PASI); patient pain visual analog score (VAS); patient global disease activity VAS; Health Assessment Questionnaire (HAQ); Leeds Enthesitis Index (LEI); Bath Ankylosing Spondylitis Disease Activity Index (BASDAI); Bath Ankylosing Spondylitis Functional Index (BASFI); Power Doppler Ultrasound (PDUS) of the involved joints and entheses, Contrast Enhanced Ultrasound (CEUS) of a selected joint or enthesis and laboratory inflammation tests.Results:31 out of the 35 enrolled patients, experienced a disease recurrence with an average disease-free interval of 27.9±21.1 weeks (Figure 1). In 3 patients the treatment was restored for a relapse of the skin psoriasis, 8 patients reported only axial symptoms of disease relapse and 20 patients had both axial and peripheral joints involvement (average DAPSA score of 23.6±11.1; average BASDAI score of 4.7±2.6; average BASFI score 4.5±2.9). In all cases the disease flare was moderate and all patients promptly regained remission after restarting the treatment. Both PDUS and CEUS were safe and reliable showing a good percentage of accordance (95,4%) in detecting synovitis and enthesitis.Conclusion:The rate of disease relapse of PsA after anti-TNF discontinuation is relevant. However the disease-free interval was not short. Retreatment with the same anti-TNF was effective and safe.References:[1]Gossec L, Baraliakos X, Kerschbaumer A, et al. EULAR recommendations for the management of psoriatic arthritis with pharmacological therapies: 2019 update. Ann Rheum Dis. 2020 Jun;79(6):700-712.[2]Dures E, Shepperd S, Mukherjee S, et al. Treat-to-target in PsA: methods and necessity. RMD Open. 2020 Feb;6(1):e001083.[3]Stober C, Ye W, Guruparan T, et al. Prevalence and predictors of tumour necrosis factor inhibitor persistence in psoriatic arthritis. Rheumatology (Oxford). 2018 Jan 1;57(1):158-163.[4]Huynh DH, Boyd TA, Etzel CJ, et al. Persistence of low disease activity after tumour necrosis factor inhibitor (TNFi) discontinuation in patients with psoriatic arthritis. RMD Open. 2017 Jan 16;3(1):e000395.[5]Ye W, Tucker LJ, Coates LC. Tapering and Discontinuation of Biologics in Patients with Psoriatic Arthritis with Low Disease Activity. Drugs. 2018 Nov;78(16):1705-1715.Disclosure of Interests:None declared.

The study generally aimed to determine the policymaking competence of legislators in the municipal councils in Eastern Visayas. A total of seventy-six (76) randomly sampled population served as respondents. The data were collected through survey questionnaire and treated it with the application of SPSS. The study found out that the legislators were middle-agedwith a mean of 44.55 and dominated by married males comprising 48 or 63.2 percent. Meanwhile, most legislators were Roman Catholics and Cebuano speaking with 70 or 92.1 and 48 % or 63.2 percent. Majority (37 or 48.7 %) were professionals with different disciplines. Their average annual family income was Php 319,033.92. In addition, their political orientations were toward the party in power with 55.2 percentand were new termers with 33 or 43.4 percent who were loyal to the party with a mean of 4.15. The major findings revealed that only some policy system manifestations and values system variables had significant relationship with policymaking competence. The relationship was influenced by some moderator and intervening variables. However, both legislators registered a high rating in policymaking competency with a mean of 3.99 and 3.97 respectively. It means they are highly competent. Therefore, the failure to address the poverty and unemployment problems inEastern Visayasas elucidated in the thesis of this study is not attributable to competency of municipal councils.

The survival of unbound density substructure against orbital mixing imposes strong constraints on the slope of the underlying gravitational potential and provides a new test on modified gravities. Here we investigate whether the interpretation that the stellar clump in Ursa Minor (UMi) dwarf spheroidal galaxy is a `dynamical fossil' is consistent with Modified Newtonian dynamics (MOND). For UMi mass models inferred by fitting the velocity dispersion profile, the stellar clump around the second peak of UMi is erased very rapidly, within 1.25 Gyr (6.5 orbits), even with the inclusion of self-gravity. We find that the clump can hardly survive for more than 2 Gyr even under more generous conditions. Alternative scenarios which could lead to a kinematically cold clump are discussed but, so far, none of them were found to be fully satisfactory. Our conclusion is that the cold clump in UMi poses a challenge for both LambdaCDM and MOND.

The radiation from newly born stars photoevaporates their parental neutral cloud, leading to the formation of dense clumps that will eventually form stars. We present 3D simulations of the interaction of a neutral cloud with an external ionising radiation field, and compute the angular momenta of these collapsing clumps. The angular momenta of these collapsing clumps show that they have preferential orient mostly perpendicular to the direction of the incident ionising photon field. Therefore, the axes of the jet systems that will be eventually ejected (from the star + accretion disk systems that will form) will be oriented approximately perpendicular to the direction to the photoionising source., 6 pages, 7 figures, accepted in Astronomy and Astrophysics

The well-established correlations between the mass of massive black holes (BHs) in the nuclei of most studied galaxies and various global properties of their hosting galaxy lend support to the idea that dwarf galaxies and globular clusters could also host a BH in their centers. Direct kinematic detection of BHs in dwarf spheroidal (dSph) galaxies are seriously hindered by the small number of stars inside the gravitational influence region of the BH. The aim of this Letter is to establish an upper dynamical limit on the mass of the putative BH in the Ursa Minor (UMi) dSph galaxy. We present direct N-body simulations of the tidal disruption of the dynamical fossil observed in UMi, with and without a massive BH. We find that the observed substructure is incompatible with the presence of a massive BH of (2-3)x10^4 Msun within the core of UMi. These limits are consistent with the extrapolation of the M_{BH}-sigma relation to the M_{BH}, 6 pages, 3 figures, ApJL (in press)

We establish new dynamical constraints on the mass and abundance of compact objects in the halo of dwarf spheroidal galaxies. In order to preserve kinematically cold the second peak of the Ursa Minor dwarf spheroidal (UMi dSph) against gravitational scattering, we place upper limits on the density of compact objects as a function of their assumed mass. The mass of the dark matter constituents cannot be larger than 1000 solar masses at a halo density in UMi's core of 0.35 solar masses/pc^3. This constraint rules out a scenario in which dark halo cores are formed by two-body relaxation processes. Our bounds on the fraction of dark matter in compact objects with masses >3000 solar masses improve those based on dynamical arguments in the Galactic halo. In particular, objects with masses $\sim 10^{5}$ solar masses can comprise no more than a halo mass fraction $\sim 0.01$. Better determinations of the velocity dispersion of old overdense regions in dSphs may result in more stringent constraints on the mass of halo objects. For illustration, if the preliminary value of 0.5 km/s for the secondary peak of UMi is confirmed, compact objects with masses above $\sim 100$ solar masses could be excluded from comprising all its dark matter halo., 6 pages, 2 figures, accepted for publication in ApJ Letters

Dwarf spheroidal galaxies are the most common type of galaxies, and are the most dark matter dominated objects in the Universe. Therefore, they are ideal laboratories to test any dark matter model. The Bose-Einstein condensate/scalar field dark matter model considers that the dark matter is composed by spinless-ultra-light particles which can be described by a scalar field. This model is an alternative to the $\Lambda$-cold dark matter model. In this work I study the kinematics of the dwarf spheroidal satellite galaxies of the Milky Way and Andromeda, under the scalar field/BEC dark matter paradigm in two limits: when the self interacting parameter is equal to zero, and when the self interacting parameter is $\gg1$. I find that dwarf spheroidal galaxies with very high mass-to-light ratios (higher than $100$) are in better agreement with an NFW mass density profile. On the other hand, dwarf spheroidal galaxies with relatively low mass-to-light ratios and high luminosities are better described with the SFDM model. Such results are very encouraging to further test alternative dark matter models using the dynamics of dwarf galaxies as a tool., Comment: 10 pages, 6 Figures. Published in ApJ

"We present a global balance “Str ̈omgren sphere” approach fo r the case of dusty HII regions. From this model, we obtain prescriptions for the outer radius of the nebulae as a function of the Str ̈omgren radius R S (of the corresponding dust-free nebula) and the dust optical depth. We also obtain a new, approximate analytic solution for the radiative transfer problem, givi ng analytic forms for the ionization fraction as a function of radius. These solution s are compared with the results obtained from the Str ̈omgren sphere approach. Our r esults can be used to evaluate under what conditions the presence of dust can have an important effect on the structures of HII regions."

Dwarf Galaxies are the most common objects in the Universe and are believed to contain large amounts of dark matter. There are mainly three morphologic types of dwarf galaxies: dwarf ellipticals, dwarf spheroidals and dwarf irregulars. Dwarf irregular galaxies are particularly interesting in dwarf galaxy evolution, since dwarf spheroidal predecessors could have been very similar to them. Therefore, a mechanism linked to gas-loss in dwarf irregulars should be observed, i.e. ram pressure stripping. In this paper, we study the interaction between the ISM of a dwarf galaxy, and a flowing IGM. We derive the weak-shock, plasmon solution corresponding to the balance between the post-bow shock pressure and the pressure of the stratified ISM (which we assume follows the fixed stratification of a gravitationally dominant dark matter halo). We compare our model with previously published numerical simulations and with the observed shape of the HI cloud around the Ho II and Pegasus dwarf irregular galaxies. We show that such a comparison provides a straightforward way for estimating the Mach number of the impinging flow., 9 pages, 5 figures. Accepted for publication in RevMexAA

The Bose-Einstein condensate/scalar field dark matter model, considers that the dark matter is composed by spinless-ultra-light particles which can be described by a scalar field. This model is an alternative model to the $\Lambda$-cold dark matter paradigm, and therefore should be studied at galactic and cosmological scales. Dwarf spheroidal galaxies have been very useful when studying any dark matter theory, because the dark matter dominates their dynamics. In this paper we study the Sextans dwarf spheroidal galaxy, embedded in a scalar field dark matter halo. We explore how the dissolution time-scale of the stellar substructures in Sextans, constrain the mass, and the self-interacting parameter of the scalar field dark matter boson. We find that for masses in the range $(0.12< m_{\phi}, Comment: 18 pages, 5 figures, 1 table. Submitted to JCAP

The EUV photoionizing radiation and FUV dissociating radiation from newly born stars photoevaporate their parental neutral cloud, leading to the formation of dense clumps that could eventually form additional stars. We study the effects of including a photodissociating FUV flux in models of the fragmentation of a photoevaporating, self-gravitating molecular cloud. We compute 3D simulations of the interaction of an inhomogeneous, neutral, self-gravitating cloud with external EUV and FUV radiation fields, and calculate the number of collapsing clumps and their mass. We find that the presence of an outer photodissociation region has an important effect on the formation of dense structures due to the expansion of an HII region. In particular, including a FUV field leads to the earlier formation of a larger number of dense clumps, which might lead to the formation of more stars.

Resumen El angiomixoma agresivo es un tumor mesenquimal poco frecuente, de crecimiento localmente infiltrativo y alto riesgo de recidiva local. Presentamos un caso de localizacion vulvar.

We study analytically the effect of radiation pressure (associated with photoionization processes and with dust absorption) on spherical, hydrostatic H ii regions. We consider two basic equations, one for the hydrostatic balance between the radiation-pressure components and the gas pressure, and another for the balance among the recombination rate, the dust absorption, and the ionizing photon rate. Based on appropriate mathematical approximations, we find a simple analytic solution for the density stratification of the nebula, which is defined by specifying the radius of the external boundary, the cross section of dust absorption, and the luminosity of the central star. We compare the analytic solution with numerical integrations of the model equations of Draine, and find a wide range of the physical parameters for which the analytic solution is accurate.

Observations seem to support that dwarf Spheroidal (dSph) galaxies have a cored halo. Ursa Minor (UMi) is one of the most dark-matter dominated dSph in the Local Group and the long survival time of its cold stellar clump can be explainedwith a large enough core in its density profile. Bosonic dark matter predicts cored halos in a natural way. The size of the core depends on the mass m of the dark matter boson and on the strength of the boson self-interaction λ . In this work we constrain m and m4/λ such as the core in bosonic halos be compatible with the survival time of UMi's clump.

We present a new Spitzer IRAC images of the HH 34 outflow. These are the first images that detect both the knots along the southern jet and the northern counterjet (the counterjet knots were only detected previously in a long slit spectrum). This result removes the problem of the apparent coexistence of a large scale symmetry (at distances of up to approx.1 pc) and a complete lack of symmetry close to the source (at distances of approx. 1.e+17 cm) for this outflow. We present a quantitative evaluation of the newly found symmetry between the HH 34 jet and counterjet, and show that the observed degree of symmetry implies that the jet production region has a characteristic size, Accepted for publication, ApJL

"We present an analytic, ballistic model for quasi-symmetric jet/counterjet systems, considering both the non-relativistic and the relativistic cases. The model considers the presence of ejection time and velocity asymmetries, which produce offsets between the positions of the knots in jet/counterjet pairs. A fit of the nonrelativistic model predictions to observations of two quasi-symmetric HH outflows (HH 34 and HH 111) allows us to obtain the magnitudes of the ejection time and velocity asymmetries of these systems."

Circumscribed palmoplantar hypokeratosis (CPH) is a recently recognized, rarely reported dermatosis that shows characteristic clinicopathological features; however, its pathogenesis remains unknown.The aim of this study was to get further insight into the pathogenesis of CPH.An immunohistological study was performed on five cases of CPH to investigate the expression of several epidermal proliferation and differentiation proteins, with emphasis on those involved in corneocyte desquamation [including corneodesmosin, kallikrein 5 and lympho-epithelial Kazal type inhibitor (LEKTI)].In three of five cases, a decreased expression of LEKTI, corneodesmosin and filaggrin was found, along with an increased expression of kallikrein 5 and keratin 6. The expression of several other antigens (including involucrin, Ki67, p63, CD138/syndecan I, EGF-R) did not present a consistently different pattern as compared with the unaffected epidermis.The immunohistopathologic features of CPH suggest that an altered (accelerated) corneocyte desquamation process could be the main pathological mechanism underlying the development of lesions.

The radiation from newly born massive stars photoionize and erode the parental molecular cloud, producing structures such as the so-called elephant trunks. At the head of an elephant trunk, the interaction of theshock (driven by the photo evaporation process) with previously existing density perturbations leads to the formation of dense clumps. Some of these clumps have enough mass to be auto-gravitating, and therefore can eventually form new stars. We carry out a 3D simulation of this process, and from the results we compute the angular momenta of these collapsing clumps. We show that the angular momenta of the clumps have preferential directions, which in principle indicate the directions in which jets will eventually be ejected from the star+accretion disk systems that will be formed.

The cold dark matter (CDM) model has two unsolved issues: simulations overpredict the satellite abundance around the Milky Way (MW) and it disagrees with observations of the central densities of dwarf galaxies which prefer constant density (core) profiles.One alternative explanation known as the scalar field dark matter (SFDM) model, assumes that the dark matter is a scalar field of mass($\sim 10^{-22}$ eV/$c^2$); this model can reduce the overabundance issue due to the lack of halo formation below a mass scale of $\sim 10^8$M$_{\odot}$ and successfully fits the density distribution in dwarfs. One of the attractive features of the model is predicting core profiles in halos, although the determination of the core sizes is set by fitting the observational data. We perform \textit{N}-body simulations to explore the influence of tidal forces over a stellar distribution embedded in a SFDM halo orbiting a MW-like SFDM host halo with a disk. Our simulations intend to test the viability of SFDM as an alternative model by comparing the tidal effects that result in this paradigm with those obtained in CDM for similar mass halos. We found that galaxies in subhalos with core profiles and high central densities survive for 10 Gyr. The same occurs for galaxies in low density subhalos located far from the host disk influence, whereas satellites in low density DM halos and in tight orbits can eventually be stripped of stars. We conclude that SFDM shows consistency with results from CDM for dwarf galaxies, but naturally offer a possibility to solve the missing satellite problem., Comment: 17 pages, 6 figures, matches the accepted version in ApJ

The cold dark matter model predicts cuspy dark matter halos. However, it has been found that, in some low-mass galaxies, cored dark halos provide a better description of their internal dynamics. Here we give constraints on the dark halo profile in the Sextans dwarf spheroidal galaxy by studying the longevity of two cold kinematic substructures detected in this galaxy. We perform N-body simulations of a stellar clump in the Sextans dwarf galaxy, including a live dark matter halo and the main stellar component. We find that, if the dark halo is cuspy, stellar clumps orbiting with semi-major axis ~400 pc are disrupted in ~5 Gyr, even if the clump is initially as compact stellar cluster with a radius of r_c=5 pc. Stellar clusters in an initial orbit with semi-major axis \leq 250 pc may survive to dissolution but their orbits decay towards the center by dynamical friction. In contrast, the stellar clumps can persist for a Hubble time within a cored dark matter halo, even if the initial clump's radius is as extended as r_c=80 pc. We also study the evolution of the clump in the MONDian context. In this scenario, we find that even an extended stellar clump with radius r_c=80 pc survives for a Hubble time, but an unrealistic value for the stellar mass-to-light ratio of 9.2 is needed., 11 pages, 7 figures, 2 tables. Accepted for publication in ApJ

We study archival HST [S II] 6716+30 and Hα images of the HH 34 outflow, taken in 1998.71 and in 2007.83. The ~9 yr time baseline and the high angular resolution of these observations allow us to carry out a detailed proper-motion study. We determine the proper motions of the substructure of the HH 34S bow shock (from the [S II] and Hα frames) and of the aligned knots within ~30'' from the outflow source (only from the [S II] frames). We find that the present-day motions of the knots along the HH 34 jet are approximately ballistic, and that these motions directly imply the formation of a major mass concentration in ~900 yr, at a position similar to the one of the present-day HH 34S bow shock. In other words, we find that the knots along the HH 34 jet will merge to form a more massive structure, possibly resembling HH 34S.

We consider the hypothesis that galactic dark matter is composed of ultra-light scalar particles and use internal properties of dwarf spheroidal galaxies to establish a preferred range for the mass m of these bosonic particles. We re-investigate the problem of the longevity of the cold clump in Ursa Minor and the problem of the rapid orbital decay of the globular clusters in Fornax and dwarf ellipticals. Treating the scalar field halo as a rigid background gravitational potential and using N-body simulations, we have explored how the dissolution timescale of the cold clump in Ursa Minor depends on m. It is demonstrated that for masses in the range 0.3x10^-22 eV < m, Accepted for publication in JCAP. Discussion about dynamical friction expanded, new explanatory figures added. Conclusions unchanged

We present Spitzer Infrared Array Camera images of the Herbig-Haro (HH) 111 outflow that show a wealth of condensations/knots in both jet and counterjet. Studying the positional distribution of these knots, we find very suggestive evidence of a mirror symmetric pattern in the jet/counterjet flow. We model this pattern as the result of an orbital motion of the jet source around a binary companion. From a fit of an analytic, ballistic model to the observed path of the HH 111 system, we find that the motion in a binary with two {approx}1 M{sub sun} stars (one of them being the HH 111 source), in a circular orbit with a separation of {approx}186 AU, would produce the mirror symmetric pattern seen in the outflow.

Alopecia Areata (AA) is an organ-specific autoimmune disorder that targets anagen phase hair follicles. The course is unpredictable and current available treatments have variable efficacy. Nowadays, there is relatively little evidence on treatment of AA from well-designed clinical trials. Moreover, none of the treatments or devices commonly used to treat AA are specifically approved by the Food and Drug Administration (FDA). The Italian Study Group for Cutaneous Annexial Disease of the Italian Society of dermatology (SIDeMaST) proposes these Italian guidelines for diagnosis and treatment of Alopecia Areata deeming useful for the daily management of the disease. This article summarizes evidence-based treatment associated with expert-based recommendations.