Massive 70 micron quiet clumps I: evidence of embedded low/intermediate-mass star formation activity

Massive clumps, prior to the formation of any visible protostars, are the best candidates to search for the elusive massive starless cores. In this work we investigate the dust and gas properties of massive clumps selected to be 70 micron quiet, therefore good starless candidates. Our sample of 18 clumps has masses 300 < M < 3000 M_sun, radius 0.54 < R < 1.00 pc, surface densities Sigma > 0.05 g cm^-2 and luminosity/mass ratio L/M < 0.3. We show that half of these 70 micron quiet clumps embed faint 24 micron sources. Comparison with GLIMPSE counterparts shows that 5 clumps embed young stars of intermediate stellar mass up to ~5.5 M_sun. We study the clump dynamics with observations of N2H+ (1-0), HNC (1-0) and HCO+ (1-0) made with the IRAM 30m telescope. Seven clumps have blue-shifted spectra compatible with infall signatures, for which we estimate a mass accretion rate 0.04 < M_dot < 2.0 x 10^-3 M_sun yr^-1, comparable with values found in high-mass protostellar regions, and free-fall time of the order of t_ff = 3 x 10^5 yr. The only appreciable difference we find between objects with and without embedded 24 micron sources is that the infall rate appears to increase from 24 micron dark to 24 micron bright objects. We conclude that all 70 micron quiet objects have similar properties on clump scales, independently of the presence of an embedded protostar. Based on our data we speculate that the majority, if not all of these clumps may already embed faint, low-mass protostellar cores. If these clumps are to form massive stars, this must occur after the formation of these lower mass stars.Comment: 44 pages, 11 Figures. Accepted for publication in MNRA

Lactococcus garvieae endocarditis in a patient undergoing chronic hemodialysis. First case report in Chile and review of the literature

Indexación: Scopus; Scielo.Los casos reportados de infección por Lactococcus garvieae son escasos y sólo uno asociado a hemodiálisis. Comunicamos el caso de endocarditis infecciosa de curso fatal por L. garvieae en un paciente con una enfermedad renal crónica sometido a hemodiálisis y portador de diverticulosis colónica no complicada. Se realiza una revisión de los casos publicados y se discuten los actuales desafíos diagnósticos y terapéuticos de este patógeno, capaz de producir infecciones graves y potencialmente fatales en pacientes susceptibles. Este sería el segundo caso de infección asociada a hemodiálisis y el primero reportado en Chile.Reports of Lactococcus garvieae infections in humans are scarce, and only one of them in a patient under-going hemodialysis. We report the first case of Lactococcus garvieae infection in Chile, presenting as an infective endocarditis, ultimately fatal, in a patient with uncomplicated colonic diverticulosis and end stage renal failure undergoing chronic hemodialysis. We review the published cases and discuss the diagnostic and therapeutic challenges associated with this new, increasingly diagnosed pathogen, capable of producing serious infections in susceptible patients.https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0716-10182017000400397&lng=en&nrm=iso&tlng=e

Sacral agenesis: a pilot whole exome sequencing and copy number study

Background: Caudal regression syndrome (CRS) or sacral agenesis is a rare congenital disorder characterized by a constellation of congenital caudal anomalies affecting the caudal spine and spinal cord, the hindgut, the urogenital system, and the lower limbs. CRS is a complex condition, attributed to an abnormal development of the caudal mesoderm, likely caused by the effect of interacting genetic and environmental factors. A well-known risk factor is maternal type 1 diabetes. Method: Whole exome sequencing and copy number variation (CNV) analyses were conducted on 4 Caucasian trios to identify de novo and inherited rare mutations. Results: In this pilot study, exome sequencing and copy number variation (CNV) analyses implicate a number of candidate genes, including SPTBN5, MORN1, ZNF330, CLTCL1 and PDZD2. De novo mutations were found in SPTBN5, MORN1 and ZNF330 and inherited predicted damaging mutations in PDZD2 (homozygous) and CLTCL1 (compound heterozygous). Importantly, predicted damaging mutations in PTEN (heterozygous), in its direct regulator GLTSCR2 (compound heterozygous) and in VANGL1 (heterozygous) were identified. These genes had previously been linked with the CRS phenotype. Two CNV deletions, one de novo (chr3q13.13) and one homozygous (chr8p23.2), were detected in one of our CRS patients. These deletions overlapped with CNVs previously reported in patients with similar phenotype. Conclusion: Despite the genetic diversity and the complexity of the phenotype, this pilot study identified genetic features common across CRS patients

Cost-effectiveness of alternative methods of surgical repair of inguinal hernia

Objectives: To assess the relative cost-effectiveness of laparoscopic methods of inguinal hernia repair compared with open flat mesh and open non-mesh repair. Methods: Data on the effectiveness of these alternatives came from three systematic reviews comparing: (i) laparoscopic methods with open flat mesh or non-mesh methods; (ii) open flat mesh with open non-mesh repair; and (iii) methods that used synthetic mesh to repair the hernia defect with those that did not. Data on costs were obtained from the authors of economic evaluations previously conducted alongside trials included in the reviews. A Markov model was used to model cost-effectiveness for a five-year period after the initial operation. The outcomes of the model were presented using a balance sheet approach and as cost per hernia recurrence avoided and cost per extra day at usual activities. Results: Open flat mesh was the most cost-effective method of preventing recurrences. Laparoscopic repair provided a shorter period of convalescence and less long-term pain compared with open flat mesh but was more costly. The mean incremental cost per additional day back at usual activities compared with open flat mesh was €38 and €80 for totally extraperitoneal and transabdominal preperitoneal repair, respectively. Conclusions: Laparoscopic repair is not cost-effective compared with open flat mesh repair in terms of cost per recurrence avoided. Decisions about the use of laparoscopic repair depend on whether the benefits (reduced pain and earlier return to usual activities) outweigh the extra costs and intraoperative risks. On the evidence presented here, these extra costs are unlikely to be offset by the short-term benefits of laparoscopic repair.Luke Vale, Adrian Grant, Kirsty McCormack, Neil W. Scott and the EU Hernia Trialists Collaboratio

Testing Larson's relationships in massive clumps

We tested the validity of the three Larson relations in a sample of 213 massive clumps selected from the Herschel Hi-GAL survey and combined with data from the MALT90 survey of 3mm emission lines. The clumps have been divided in 5 evolutionary stages to discuss the Larson relations also as function of evolution. We show that this ensemble does not follow the three Larson relations, regardless of clump evolutionary phase. A consequence of this breakdown is that the virial parameter $\alpha_{vir}$ dependence with mass (and radius) is only a function of the gravitational energy, independent of the kinetic energy of the system, and $\alpha_{vir}$ is not a good descriptor of clump dynamics. Our results suggest that clumps with clear signatures of infall motions are statistically indistinguishable from clumps with no such signatures. The observed non-thermal motions are not necessarily ascribed to turbulence acting to sustain the gravity, but they may be due to the gravitational collapse at the clump scales. This seems particularly true for the most massive (M$\geq$1000 M$_{\odot}$) clumps in the sample, where also exceptionally high magnetic fields may not be enough to stabilize the collapse.Comment: Accepted for publication in MNRA

Thermal balance and comparison of gas and dust properties of dense clumps in the Hi-GAL survey

We present a comparative study of physical properties derived from gas and dust emission in a sample of 1068 dense Galactic clumps. The sources are selected from the cross-match of the Herschel Infrared Galactic Plane Survey with 16 catalogues of NH3 line emission in its lowest inversion (1,1) and (2,2) transitions. The sample covers a large range in masses and bolometric luminosities, with surface densities above Sigma = 0.1 g cm(-2) and with low virial parameters alpha < 1. The comparison between dust and gas properties shows an overall agreement between T-kin and T-dust at volumetric densities n greater than or similar to 1.2 x 10(4)cm(-3), and a median fractional abundance chi (NH3) = 1.46 x 10(-8). While the protostellar clumps in the sample have small differences between T-kin and T-dust, prestellar clumps have a median ratio T-kin/T-dust = 1.24, suggesting that these sources are thermally decoupled. A correlation is found between the evolutionary tracer L/M and the parameters T-kin/T-dust and chi(NH3) in prestellar sources and protostellar clumps with L/M < 1 L circle dot M circle dot-1 . In addition, a weak correlation is found between non-thermal velocity dispersion and the L/M parameter, possibly indicating an increase of turbulence with protostellar evolution in the interior of clumps. Finally, different processes are discussed to explain the differences between gas and dust temperatures in prestellar candidates, and the origin of non-thermal motions observed in the clumps.Sao Paulo Research Foundation (FAPESP) [2017/23708-0]; Italian Ministero dell'Istruzione Universita e Ricerca through the grant Progetti Premiali 2012-iALMA [CUP C52I13000140001]; European Union [607380]This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

The Hi-GAL compact source catalogue - II. The 360° catalogue of clump physical properties

We present the 360° catalogue of physical properties of Hi-GAL compact sources, detected between 70 and 500 μm. This release not only completes the analogous catalogue previously produced by the Hi-GAL collaboration for -71° ≲ ℓ ≲ 67°, but also meaningfully improves it because of a new set of heliocentric distances, 120 808 in total. About a third of the 150 223 entries are located in the newly added portion of the Galactic plane. A first classification based on detection at 70 μm as a signature of ongoing star-forming activity distinguishes between protostellar sources (23 per cent of the total) and starless sources, with the latter further classified as gravitationally bound (pre-stellar) or unbound. The integral of the spectral energy distribution, including ancillary photometry from λ = 21 to 1100 μm, gives the source luminosity and other bolometric quantities, while a modified blackbody fitted to data for λ ≥ 160μm yields mass and temperature. All tabulated clump properties are then derived using photometry and heliocentric distance, where possible. Statistics of these quantities are discussed with respect to both source Galactic location and evolutionary stage. No strong differences in the distributions of evolutionary indicators are found between the inner and outer Galaxy. However, masses and densities in the inner Galaxy are on average significantly larger, resulting in a higher number of clumps that are candidates to host massive star formation. Median behaviour of distance-independent parameters tracing source evolutionary status is examined as a function of the Galactocentric radius, showing no clear evidence of correlation with spiral arm positions

123I-2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl) nortropane single photon emission computed tomography and 123I-metaiodobenzylguanidine myocardial scintigraphy in differentiating dementia with lewy bodies from other dementias: A comparative study

Objective: To compare the diagnostic value of striatal 123I-2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl) nortropane (123I-FP-CIT) single photon emission computed tomography (SPECT) and 123I-metaiodobenzylguanidine (123I-MIBG) myocardial scintigraphy in differentiating dementia with Lewy bodies (DLB) from other dementia types. Methods: This prospective longitudinal study included 30 patients with a clinical diagnosis of DLB and 29 patients with non-DLB dementia (Alzheimer disease, n = 16; behavioral variant frontotemporal dementia, n = 13). All patients underwent 123I-FP-CIT SPECT and 123I-MIBG myocardial scintigraphy within a few weeks of clinical diagnosis. All diagnoses at each center were agreed upon by the local clinician and an independent expert, both unaware of imaging data, and re-evaluated after 12 months. Each image was visually classified as either normal or abnormal by 3 independent nuclear physicians blinded to patients' clinical data. Results: Overall, sensitivity and specificity to DLB were respectively 93% and 100% for 123I-MIBG myocardial scintigraphy, and 90% and 76% for 123I-FP-CIT SPECT. Lower specificity of striatal compared to myocardial imaging was due to decreased 123I-FP-CIT uptake in 7 non-DLB subjects (3 with concomitant parkinsonism) who had normal 123I-MIBG myocardial uptake. Notably, in our non-DLB group, myocardial imaging gave no false-positive readings even in those subjects (n = 7) with concurrent medical illnesses (diabetes and/or heart disease) supposed to potentially interfere with 123I-MIBG uptake. Interpretation: 123I-FP-CIT SPECT and 123I-MIBG myocardial scintigraphy have similar sensitivity for detecting DLB, but the latter appears to be more specific for excluding non-DLB dementias, especially when parkinsonism is the only “core feature” exhibited by the patient. Our data also indicate that the potential confounding effects of diabetes and heart disease on 123I-MIBG myocardial scintigraphy results might have been overestimated. Ann Neurol 2016;80:368–378

Distance of Hi-GAL sources

Aims. Distances are key to determining the physical properties of sources. In the Galaxy, large (> 10 000) homogeneous samples of sources for which distance are available, covering the whole Galactic distance range, are still missing. Here we present a catalog of velocity and distance for a large sample (> 100 000) of Hi-GAL compact sources. Methods. We developed a fully automatic Python package to extract the velocity and determine the distance. To assign a velocity to a Hi-GAL compact source, the code uses all the available spectroscopic data complemented by a morphological analysis. Once the velocity is determined, if no stellar or maser parallax distance is known, the kinematic distance is calculated and the distance ambiguity (for sources located inside the Solar circle) is solved with the H I self-absorption method or from distance-extinction data. Results. Among the 150 223 compact sources of the Hi-GAL catalog, we obtained a distance for 124 069 sources for the 5σ catalog (and 128 351 sources for the 3σ catalog), where σ represents the noise level of each molecular spectrum used for the line detections made at 5σ and 3σ to produce the respective catalogs. © P. Mège et al. 2021