Turbulent Flow-Driven Molecular Cloud Formation: A Solution to the Post-T Tauri Problem?

We suggest that molecular clouds can be formed on short time scales by compressions from large scale streams in the interstellar medium (ISM). In particular, we argue that the Taurus-Auriga complex, with filaments of 10-20 pc $\times$ 2-5 pc, most have been formed by H I flows in $\lesssim 3$Myr, explaining the absence of post-T Tauri stars in the region with ages $\gtrsim 3$ Myr. Observations in the 21 cm line of the H I `halos' around the Taurus molecular gas show many features (broad asymmetric profiles, velocity shifts of H I relative to $^{12}$CO) predicted by our MHD numerical simulations, in which large-scale H I streams collide to produce dense filamentary structures. This rapid evolution is possible because the H I flows producing and disrupting the cloud have much higher velocities (5-10 kms) than present in the molecular gas resulting from the colliding flows. The simulations suggest that such flows can occur from the global ISM turbulence without requiring a single triggering event such as a SN explosion.Comment: 26 pages, 12 ps figures. Apj accepte

Physical vs. Observational Properties of Clouds in Turbulent Molecular Cloud Models

We examine how well the physical properties of clumps in turbulent molecular clouds can be determined by measurements of observed clump structures. We compare simulated observations of three-dimensional numerical models of isothermal, magnetized, supersonic turbulence to the actual physical structure of the models. We determine how changing the parameters of turbulence changes the structure of the simulations. Stronger driving produces greater density fluctuations, and longer wavelength driving produces larger structures. Magnetic fields have a less pronounced effect on structure, and one that is not monotonic with field strength. Aligned structures are seen only with low-density tracers, and when the intensity of the field is large. Comparing different regions with the same tracers (or the same region with different tracers) can give information about physical conditions: different density tracers can help determine the size of the density fluctuations and thus the strength of the driving. Nevertheless, velocity superposition of multiple physical clumps can fully obscure the physical properties of those clumps, and short wavelength driving worsens this effect. Regarding Larson's relationships, we confirm previous claims that the mean density-size relationship is an artifact of the observations; and the velocity dispersion-size relationship, is consistent with observations. Regarding the mass spectra, we show that, when we look for clumps with high enough resolution, they converge to a log-normal function, rather than the power-law obtained in the literature.Comment: ApJ accepted. 14 gif figures. PS file available at ftp://ftp.astrosmo.unam.mx/pub/j.ballesteros/Papers

Welded, sandblasted, stainless steel corrugated bars in non-carbonated and carbonated mortars: A 9-year corrosion study

Three different stainless steel corrugated grades (UNS S20430, S30403 and S32205) were similar welded to stainless steel bars with the same composition and dissimilar welded to carbon steel (CS). After cleaning the welding oxides by sandblasting, the reinforcements were embedded in mortar with chlorides and some of the samples were carbonated. Corrosion activity was monitored using corrosion potential (Ecorr) and electrochemical impedance spectroscopy (EIS). After 8 years of exposure, the samples were anodically polarized. Visual evaluation of the attack was performed after another additional year of exposure. Similar welded stainless steels offer a good durability if they have been sandblasted, except for S20430 when it is embedded in carbonated mortar with chlorides. Dissimilar welded steels are active since the beginning of the exposure for both studied conditions, but sandblasting reduces the corrosion rate of CS compared to non-welded CS bars.The present work was funded by the Spanish Ministry of Science and Innovation through the Project reference BIA2007-66491-C02-02

Influence of the forming process of corrugated stainless steels on their corrosion behaviour in simulated pore solutions

Stainless steels are formed by either hot working (HW) or cold working (CW) when used as reinforcement for concrete structures. The influence of the forming process on the corrosion behaviour is analyzed in depth in the present work. CW and HW corrugated bars of austenitic AISI 304L and 316L, and duplex SAF 2205 grades are studied. The electrochemical behaviour of the corrugated surface and the core of these materials are characterized by Mott Schottky analysis and polarization curves. Tests are carried out in both carbonated and non carbonated Ca(OH)2 solutions. The microstructure and local mechanical properties of these materials are also analysed by means of universal hardness (UH) measurements to complete available information. The results prove that the surface of corrugated bars is far more likely to suffer corrosion than the core of the same material. The corrosion probability and the morphology of the attack induced in corrugated surfaces by anodic polarization clearly differ in HW and CW bars.The authors wish to acknowledge the Spanish Ministry of Science and Innovation (through project BIA2007 66491 C02 02) for its financial support in this research

Corrugated stainless steels embedded in mortar for 9 years: corrosion results of non-carbonated, chloride-contaminated samples

Mortar samples reinforced with 5 different corrugated stainless steels were tested for 9 years in 2 different conditions: partial immersion (PI) in 3.5% NaCl, and chloride addition to the mortar and exposure to high relative humidity (HRH). The monitoring during the exposures was carried out with corrosion potential (E-corr) and electrochemical impedance spectroscopy (EIS) measurements. A year before finishing (after 8 years of exposure), the reinforced mortar samples were anodically polarised to obtain more information about the pitting resistance of the passive layers formed under the different conditions. The last year of exposure was established to study the progress or repassivation of the pits. The PI is the most aggressive testing condition and it causes low-intensity corrosion in S20430 austenitic stainless steel after 7 years of exposure. The S32205 duplex stainless steel shows very good corrosion behaviourThe present work was funded by the Spanish Ministry of Science and Innovation through the Project reference BIA2007 66491 C02 02

Derecho a la educación de niños y niñas en situación de movilidad internacional

Last past years Latinoamerica has been a migratory escenary without precedents, as a consecuence from that, complete families have been moving from different countries searching for better opportunities. In this context, the right to education in children population, indeed this context, has been affected, above all having difficulties to be part of educational systems in the transit or destiny countries. In 2021 the International Integration Institute of the Andrés Bello Organization Agreement (Instituto Internacional de Integración de la Organización del Convenio Andrés Bello) in La Paz – Bolivia, has developed an investigation designated to identify the mechanisms to warranty the Childrens’ Education Right in International Mobility Situation in Bolivia. The investigation has been implemented starting with three components. The first one assigned to recognice the children study knowledge throught the CAB Equivalence Chart; the second, to the Educational Support Program implementation to children’s in mobility situation and, the third, to teachers training based on classroom educative integration. In this way, under intercultural educative approach, the mechanims and actions of many actors committed, it has been running the process of children’s education inclusión in international mobility situation. En los últimos años, Latinoamérica ha sido escenario de un fenómeno migratorio sin precedentes, como consecuencia de ello familias íntegras han tenido que transitar por distintos países en busca de mejores oportunidades. En ese contexto, el derecho a la educación de la población infantil, inmersa en este fenómeno, se ha visto afectado, sobre todo al tener dificultades para incorporarse a los sistemas educativos de los países de tránsito y de destino. El año 2021 el Instituto Internacional de Integración de la Organización del Convenio Andrés Bello,con sedeen La Paz - Bolivia, ha desarrollado unainvestigación destinada a identificar los mecanismos para garantizar el derecho a la educación de niñas y niños en situación de movilidad internacional asentados en Bolivia1. La investigación ha sido ejecutada a partir de tres componentes. El primero destinado al reconocimiento de los estudios de los niños y niñas mediante el instrumento de la Tabla de Equivalencias del CAB; el segundo, a la implementación de un programa de apoyo educativo para niños y niñas en situación de movilidad y, el tercero a la capacitación docente en torno a la integración educativa en las aulas. De esa manera, bajo el enfoque educativo intercultural, los mecanismos y acciones de diversos actores comprometidos, se ha puesto en marcha el proceso de inclusión educativa de los niños y niñas en situación de movilidad internacional

The effects of perceived COVID-19 threat on compensatory conviction, thought reliance, and attitudes

This research examines how people can defend themselves from the threat associated with the COVID-19 pandemic by relying more on their recently generated thoughts (unrelated to the threat), thus leading those thoughts to have a greater impact on judgement through a meta-cognitive process of thought validation. Study 1 revealed that the impact of the favourability of self-related thoughts on self-esteem was greater for those feeling relatively more (vs. less) threatened by COVID-19. Study 2 manipulated (rather than measured) the favourability of thoughts and assessed the perceived COVID-19 threat. Results also showed that the impact of thoughts on subsequent self-evaluations was greater for those feeling more threatened by COVID-19. Study 3 conceptually replicated the results using a full experimental design by manipulating both thought favourability andthe perceived COVID-19 threat, moving from the self to a social perception paradigm, and providing mediational evidence for the proposed mechanism of compensatory thought validation. A final study addressed some alternative explanations by testing whether the induction of threat used in Study 3 affected perceptions of threat while not having an impact on other featuresMinisterio de Ciencia e Innovación, Gobierno de España (ES), Grant/Award Number: PID2020-116651GB-C31;PID2020- 116651GBC33/AEI/10.13039/501100011033; Consejería de Ciencia, Universidades e Innovación, Comunidad de Madrid, Grant/Award Number: SI3/PJI/2021-0047

UHPLC-MS Phenolic Fingerprinting, Aorta Endothelium Relaxation Effect, Antioxidant, and Enzyme Inhibition Activities of Azara dentata Ruiz & Pav Berries

Azara dentata Ruiz & Pav. is a small Chilean native plant from Patagonia, a producer of small white reddish berries. For the first time, the proximal analysis of the fruits, phenolic fingerprinting, the antioxidant activity, and the enzymatic inhibition and relaxation effects in rat aorta induced by the ethanolic extract of these fruits were investigated. The proximal composition and the mineral (Ca: 2434 ± 40 mg/kg; Mg: 702 ± 13 mg/kg; Fe: 117.1 ± 1.6 mg/kg; Zn: 16.1 ± 0.4 mg/kg) and heavy metal (As: 121 ± 11 µg/kg; Cd: 152 ± 5 µg/kg; Hg: 7.7 ± 1.3 µg/kg; Pb 294 ± 4 µg/kg) contents were analyzed. Anthocyanins, flavonoids, phenolic acids, and coumarins were identified using UHPLC-PDA-QTOF-MS. The ethanolic extracts showed a total phenolic content of 23.50 ± 0.93 mg GAE/g extract. In addition, the antioxidant activity was assessed using both DPPH and TEAC (28.64 ± 1.87 and 34.72 ± 2.33 mg Trolox/g of dry fruit, respectively), FRAP (25.32 ± 0.23 mg Trolox equivalent/g dry fruit), and ORAC (64.95 ± 1.23 mg Trolox equivalents/g dry fruit). The inhibition of enzymatic activities (acetylcholinesterase IC50: 2.87 + 0.23 µg extract/mL, butyrylcholinesterase IC50: 6.73 + 0.07 µg extract/mL, amylase IC50: 5.6 ± 0.0 µg extract/mL, lipase IC50: 30.8 ± 0.0 µg extract/mL, and tyrosinase IC50: 9.25 ± 0.15 µg extract/mL) was also assessed. The extract showed 50–60% relaxation in rat aorta (intact), mediated thorough the release of endothelial nitric oxide. Our results suggest that A. dentata is a good source of compounds with the capacity to inhibit important enzymes, can be hypotensive, and can thus have good potentiality as supplements in the amelioration of neurodegenerative diseases and could also have potential to be used to develop new functional foods. The study highlights the benefits of these neglected small fruits and could boost their consumption.Fil: Cuesta Ramos, Lucia. Universidad de Valencia; EspañaFil: Palacios, Javier. Universidad Arturo Prat (unap);Fil: Barrientos, Ruth E.. Universidad Austral de Chile; ChileFil: Gómez Pelaytay, Jessica Belén. Universidad Nacional de San Juan; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; ArgentinaFil: Castagnini, Juan Manuel. Universidad de Valencia; EspañaFil: Barba, Francisco J.. Universidad de Valencia; EspañaFil: Tapia, Alejandro. Universidad Nacional de San Juan; ArgentinaFil: Paredes, Adrián. Universidad de Antofagasta (uantof);Fil: Cifuentes, Fredi. Universidad de Antofagasta (uantof);Fil: Simirgiotis, Mario J.. Universidad Austral de Chile; Chil

Corrugated stainless steels embedded in carbonated mortars with and without chlorides: 9-year corrosion results

The corrosion behavior of 5 corrugated stainless steel bars was evaluated in carbonated mortars: UNS S20430, S30400, S31603, S31635 and S32205. The tests were carried out under 3 different exposure conditions: at high relative humidity (C-HRH); partially immersed in 3.5% NaCl (C-PD; and with CaCl2 added during mortar mixing and exposed to high relative humidity (C-HRHCl). Corrosion potential (Ecorr) measurements and electrochemical impedance spectroscopy (EIS) were used to monitor the behavior during the first 8 years of exposure. Then, anodic polarization tests were carried out and the exposure was extended for another additional year. Stainless steels do not corrode in carbonated conditions without chlorides, but some grades can suffer localized corrosion if they are submitted to high anodic polarizations. Low-Ni, austenitic S20430 corrugated bars are especially prone to suffer a low-intensity corrosive attack in carbonated mortars with chlorides. Moreover, the corrosion rate of S20430 bars can easily increase under moderate anodic polarizations. Duplex S32205 is immune to corrosion in the carbonated mortar with chlorides, even in partial immersion conditions and under high anodic polarizations.The present work was funded by the Spanish Ministry of Science and Innovation through the Project reference BIA2007 66491 C02

Root microbiota drive direct integration of phosphate stress and immunity

Plants live in biogeochemically diverse soils that harbor extraordinarily diverse microbiota. Plant organs associate intimately with a subset of these microbes; this community’s structure can be altered by soil nutrient content. Plant-associated microbes can compete with the plant and with each other for nutrients; they can also provide traits that increase plant productivity. It is unknown how the plant immune system coordinates microbial recognition with nutritional cues during microbiome assembly. We establish that a genetic network controlling phosphate stress response influences root microbiome community structure, even under non-stress phosphate conditions. We define a molecular mechanism regulating coordination between nutrition and defense in the presence of a synthetic bacterial community. We demonstrate that the master transcriptional regulators of phosphate stress response in Arabidopsis also directly repress defense, consistent with plant prioritization of nutritional stress over defense. Our work will impact efforts to define and deploy useful microbes to enhance plant performance