High Spectral and Spatial Resolution Observations of the PDR Emission in the NGC2023 Reflection Nebula with SOFIA and APEX

We have mapped the NGC 2023 reflection nebula in [CII] and CO(11--10) with the heterodyne receiver GREAT on SOFIA and obtained slightly smaller maps in 13CO(3--2), CO(3--2), CO(4--3), CO(6--5), and CO(7--6) with APEX in Chile. We use these data to probe the morphology, kinematics, and physical conditions of the C II region, which is ionized by FUV radiation from the B2 star HD37903. The [CII] emission traces an ellipsoidal shell-like region at a position angle of ~ -50 deg, and is surrounded by a hot molecular shell. In the southeast, where the C II region expands into a dense, clumpy molecular cloud ridge, we see narrow and strong line emission from high-J CO lines, which comes from a thin, hot molecular shell surrounding the [CII] emission. The [CII] lines are broader and show photo evaporating gas flowing into the C II region. Based on the strength of the [13CII] F=2--1 line, the [CII] line appears to be somewhat optically thick over most of the nebula with an optical depth of a few. We model the physical conditions of the surrounding molecular cloud and the PDR emission using both RADEX and simple PDR models. The temperature of the CO emitting PDR shell is ~ 90 -- 120 K, with densities of 10^5 -- 10^6 cm^-3, as deduced from RADEX modeling. Our PDR modeling indicates that the PDR layer where [CII] emission dominates has somewhat lower densities, 10^4 to a few times 10^5 cm^-3Comment: Accepted by A&

Characterizing the transition from diffuse atomic to dense molecular clouds in the Magellanic clouds with [CII], [CI], and CO

We present and analyze deep Herschel/HIFI observations of the [CII] 158um, [CI] 609um, and [CI] 370um lines towards 54 lines-of-sight (LOS) in the Large and Small Magellanic clouds. These observations are used to determine the physical conditions of the line--emitting gas, which we use to study the transition from atomic to molecular gas and from C^+ to C^0 to CO in their low metallicity environments. We trace gas with molecular fractions in the range 0.1<f(H2)<1, between those in the diffuse H2 gas detected by UV absorption (f(H2)<0.2) and well shielded regions in which hydrogen is essentially completely molecular. The C^0 and CO column densities are only measurable in regions with molecular fractions f(H2)>0.45 in both the LMC and SMC. Ionized carbon is the dominant gas-phase form of this element that is associated with molecular gas, with C^0 and CO representing a small fraction, implying that most (89% in the LMC and 77% in the SMC) of the molecular gas in our sample is CO-dark H2. The mean X_CO conversion factors in our LMC and SMC sample are larger than the value typically found in the Milky Way. When applying a correction based on the filling factor of the CO emission, we find that the values of X_CO in the LMC and SMC are closer to that in the Milky Way. The observed [CII] intensity in our sample represents about 1% of the total far-infrared intensity from the LOSs observed in both Magellanic Clouds.Comment: 32 pages, 21 figures, Accepted to Ap

Diagnostic Accuracy of Five Serologic Tests for Strongyloides stercoralis Infection

Background:The diagnosis of Strongyloides stercoralis (S. stercoralis) infection is hampered by the suboptimal sensitivity of fecal-based tests. Serological methods are believed to be more sensitive, although assessing their accuracy is difficult because of the lack of sensitivity of a fecal-based reference ("gold") standard.Methods:The sensitivity and specificity of 5 serologic tests for S. stercoralis (in-house IFAT, NIE-ELISA and NIE-LIPS and the commercially available Bordier-ELISA and IVD-ELISA) were assessed on 399 cryopreserved serum samples. Accuracy was measured using fecal results as the primary reference standard, but also using a composite reference standard (based on a combination of tests).Results:According to the latter standard, the most sensitive test was IFAT, with 94.6% sensitivity (91.2-96.9), followed by IVD-ELISA (92.3%, 87.7-96.9). The most specific test was NIE-LIPS, with specificity 99.6% (98.9-100), followed by IVD-ELISA (97.4%, 95.5-99.3). NIE-LIPS did not cross-react with any of the specimens from subjects with other parasitic infections. NIE-LIPS and the two commercial ELISAs approach 100% specificity at a cut off level that maintains ≥70% sensitivity.Conclusions:NIE-LIPS is the most accurate serologic test for the diagnosis of S. stercoralis infection. IFAT and each of the ELISA tests are sufficiently accurate, above a given cut off, for diagnosis, prevalence studies and inclusion in clinical trials.Fil: Bisoffi, Zeno. Sacro Cuore Hospital; ItaliaFil: Buonfrate, Dora. Sacro Cuore Hospital; ItaliaFil: Sequi, Marco. Istituto Di Ricerche Farmacologiche Mario Negri; ItaliaFil: Mejia, Rojelio. National Institute Of Allergy And Infectious Diseases; Estados UnidosFil: Cimino, Rubén Oscar. Universidad Nacional de Salta. Sede Regional Orán. Instituto de Investigación de Enfermedades Tropicales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Krolewiecki, Alejandro Javier. Universidad Nacional de Salta. Sede Regional Orán. Instituto de Investigación de Enfermedades Tropicales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Albonico, Marco. Sacro Cuore Hospital; ItaliaFil: Gobbo, Maria. Sacro Cuore Hospital; ItaliaFil: Bonafini, Stefania. Sacro Cuore Hospital; ItaliaFil: Angheben, Andrea. Sacro Cuore Hospital; ItaliaFil: Requena-Mendez, Ana. Universidad de Barcelona; EspañaFil: Muñoz, José. Universidad de Barcelona; EspañaFil: Nutman, Thomas B.. National Institute Of Allergy And Infectious Diseases; Estados Unido

Increase of CXCR3+ T cells impairs Th17 cells recruitment in the small intestine mucosa through IFN-g and IL-18 during treated HIV-1 infection

The restoration of CD4+ T cells, especially T-helper type 17 (Th17) cells, remains incomplete in the gut mucosa of most human immunodeficiency virus type 1 (HIV-1)–infected individuals despite sustained antiretroviral therapy (ART). Herein, we report an increase in the absolute number of CXCR3+ T cells in the duodenal mucosa during ART. The frequencies of Th1 and CXCR3+ CD8+ T cells were increased and negatively correlated with CCL20 and CCL25 expression in the mucosa. In ex vivo analyses, we showed that interferon γ, the main cytokine produced by Th1 and effector CD8+ T cells, downregulates the expression of CCL20 and CCL25 by small intestine enterocytes, while it increases the expression of CXCL9/10/11, the ligands of CXCR3. Interleukin 18, a pro-Th1 cytokine produced by enterocytes, also contributes to the downregulation of CCL20 expression and increases interferon γ production by Th1 cells. This could perpetuate an amplification loop for CXCR3-driven Th1 and effector CD8+ T cells recruitment to the gut, while impairing Th17 cells homing through the CCR6-CCL20 axis in treated HIV-1–infected individuals

Plastic adjustments in xylem vessel traits to drought events in three Cedrela species from Peruvian Tropical Andean forests

Cedrela species occur within the Tropical montane cloud forest (TMCF) and rainforest in North America (Mexico), Central and South America. We assessed the hypothesis that functional xylem hydraulic architecture might be influenced by specific climatic variations. We investigated the effect of climate on tree-ring width and vessel traits (diameter, vessel density, vulnerability index and hydraulic diameter) of three relict-endemic and threatened Cedrela species (Cedrela fissilis, C. nebulosa and C. angustifolia) inhabiting Peruvian Tropical Andean cloud forests. All Cedrela species showed a significant reduction in radial growth and adjusted vessel trait linked with temperature, precipitation, and evapotranspiration. Ring-width and vessel traits showed adaptation within Cedrela species, crucial to understanding a rough indication of the plant’s ability to withstand drought-induced embolism or cavitation. Our results provide evidence for hydraulic mechanisms that determine specific wood anatomical functionality to climatic variation and drought responses. Therefore, changing the frequency or intensity of future drought events might exceed the adaptive limits of TMCF tree species, resulting in a substantial reduction of hydraulic functionality in Peruvian Cedrela species.Fil: Rodríguez Ramírez, Ernesto C.. Universidad Continental; PerúFil: Ferrero, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Acevedo-Vega, Ingrith. Universidad Continental; PerúFil: Crispin DelaCruz, Doris B.. Universidad Continental; Perú. Universidade Federal de Pernambuco; BrasilFil: Ticse Otarola, Ginette Vilma Alicia. Universidad Continental; Perú. Asociación ANDINUS; PerúFil: Requena Rojas, Edilson Jimmy. Universidad Continental; Per

Amides inventory towards the G+0.693-0.027 molecular cloud

Interstellar amides have attracted significant attentions as they are potential precursors for a wide variety of organics essential to life. However, our current understanding of their formation in space is heavily based on observations in star-forming regions and hence the chemical networks lack the constraints on their early origin. In this work, unbiased sensitive spectral surveys with IRAM 30m and Yebes 40m telescopes are used to systematically study a number of amides towards a quiescent Galactic Centre molecular cloud, G+0.693-0.027. We report the first detection of acetamide (CH3C(O)NH2) and trans-N-methylformamide (CH3NHCHO) towards this cloud. In addition, with the wider frequency coverage of the survey, we revisited the detection of formamide (NH2CHO) and urea (carbamide; NH2C(O)NH2), which had been reported previously towards G+0.693-0.027. Our results are compared with those present in the literature including recent laboratory experiments and chemical models. We find constant abundance ratios independently of the evolutionary stages, suggesting that amides related chemistry is triggered in early evolutionary stages of molecular cloud and remain unaffected by the warm-up phase during the star formation process. Although a correlation between more complex amides and NH2CHO have been suggested, alternative formation routes involving other precursors such as acetaldehyde (CH3CHO), methyl isocyanate (CH3NCO) and methylamine (CH3NH2) may also contribute to the production of amides. Observations of amides together with these species towards a larger sample of sources can help to constrain the amide chemistry in the interstellar medium.Comment: 16 pages, 8 figures, 3 tables, accepted for publication in Monthly Notices of the Royal Astronomical Societ

Certificates of quantum many-body properties assisted by machine learning

Theoretical Physic

The first detection of SiC2_2 in the interstellar medium

We report the first detection of SiC$_2$ in the interstellar medium. The molecule was identified through six rotational transitions toward G\,+0.693$-$0.027, a molecular cloud located in the Galactic center. The detection is based on a line survey carried out with the GBT, the Yebes 40m, and the IRAM 30m telescopes covering a range of frequencies from 12 to 276 GHz. We fit the observed spectra assuming local thermodynamic equilibrium and derive a column density of ($1.02\pm0.04)\times10^{13}$ cm$^{-2}$, which gives a fractional abundance of $7.5\times10^{-11}$ with respect to H$_2$, and an excitation temperature of $5.9\pm0.2$ K. We conclude that SiC$_2$ can be formed in the shocked gas by a reaction between the sputtered atomic silicon and C$_2$H$_2$, or it can be released directly from the dust grains due to disruption. We also search for other Si-bearing molecules and detect eight rotational transitions of SiS and four transitions of Si$^{18}$O. The derived fractional abundances are $3.9\times10^{-10}$ and $2.1\times10^{-11}$, respectively. All Si-bearing species toward G\,+0.693$-$0.027 show fractional abundances well below what is typically found in late-type evolved stars.Comment: 8 pages, 5 figure

The validity and reliability of the my jump 2 app for measuring the reactive strength index and drop jump performance.

BACKGROUND: This is the first study to independently assess the concurrent validity and reliability of the My Jump 2 app for measuring drop jump performance. It is also the first to evaluate the app's ability to measure the reactive strength index (RSI). METHODS: Fourteen male sport science students (age: 29.5±9.9 years) performed three drop jumps from 20 cm and 40 cm (totaling 84 jumps), assessed via a force platform and the My Jump 2 app. Reported metrics included reactive strength index, jump height, ground contact time, and mean power. Measurements from both devices were compared using the intraclass correlation coefficient (ICC), Pearson product moment correlation coefficient (r), Cronbach's alpha (α), coefficient of variation (CV) and Bland-Altman plots. RESULTS: Near perfect agreement was seen between devices at 20 cm for RSI (ICC=0.95) and contact time (ICC=0.99) and at 40 cm for RSI (ICC=0.98), jump height (ICC=0.96) and contact time (ICC=0.92); with very strong agreement seen at 20 cm for jump height (ICC=0.80). In comparison with the force plate the app showed good validity for RSI (20 cm: r=0.94; 40 cm; r=0.97), jump height (20 cm: r=0.80; 40 cm; r=0.96) and contact time (20 cm=0.96; 40 cm; r=0.98). CONCLUSIONS: The results of the present study show that the My Jump 2 app is a valid and reliable tool for assessing drop jump performance

General energy bounds for systems of bosons with soft cores

We study a bound system of N identical bosons interacting by model pair potentials of the form V(r) = A sgn(p)r^p + B/r^2, A > 0, B >= 0. By using a variational trial function and the `equivalent 2-body method', we find explicit upper and lower bound formulas for the N-particle ground-state energy in arbitrary spatial dimensions d > 2 for the two cases p = 2 and p = -1. It is demonstrated that the upper bound can be systematically improved with the aid of a special large-N limit in collective field theory