Abstract
We present a detailed chemical abundance analysis of the brightest star in the ultrafaint dwarf (UFD) galaxy candidate Cetus II from high-resolution Magellan/MIKE spectra. For this star, DES ...J011740.53-173053, abundances or upper limits of 18 elements from carbon to europium are derived. Its chemical abundances generally follow those of other UFD galaxy stars, with a slight enhancement of the
α
-elements (Mg, Si, and Ca) and low neutron-capture element (Sr, Ba, and Eu) abundances supporting the classification of Cetus II as a likely UFD. The star exhibits lower Sc, Ti, and V abundances than Milky Way (MW) halo stars with similar metallicity. This signature is consistent with yields from a supernova originating from a star with a mass of ∼11.2
M
⊙
. In addition, the star has a potassium abundance of K/Fe = 0.81, which is somewhat higher than the K abundances of MW halo stars with similar metallicity, a signature that is also present in a number of UFD galaxies. A comparison including globular clusters and stellar stream stars suggests that high K is a specific characteristic of some UFD galaxy stars and can thus be used to help classify objects as UFD galaxies.
Kinetic study of solid’s thermal decomposition provides essential information about a system and its possible industrial applications. For complex materials, such as sewage sludge, several reactions ...can occur during the thermal process. Therefore, single-step methodologies as isoconversional analysis and kinetic model determination should not accurately describe the phenomenon. As an alternative, a better approach consists of determining the distribution of activation energy, which considers more than one reaction in the same thermal process. To obtain the kinetic model parameters or recover the activation energy distribution by thermal analysis, an ill-conditioned inverse problem has to be solved, and, therefore, Hopfield neural network (HNN) can be successfully used. In the present work, the results of HNN are compared with the traditional Levenberg–Marquardt algorithm. For this system, the distribution of activation energy model (DAEM) is adequate to represent the experimental data instead of kinetic model determination or isoconversional methods.
Aim
Doubt still remains as to whether peripheral vascular and skeletal muscle dysfunction accompanies the compromised cardiac function associated with heart failure with reduced ejection fraction ...(HFrEF). The aim of this study was to examine the effect of HFrEF on the haemodynamic and metabolic responses to exercise with both a large (cycle) and a small knee extensor (KE) muscle mass in comparison with well‐matched healthy controls (Ctrls).
Methods
Utilizing blood sampling and thermodilution blood flow measurements, we studied incremental cycle and KE exercise in 12 patients with HFrEF (ejection fraction: 25 ± 3%) and eight Ctrls.
Results
Incremental cycle exercise in both groups heart failure with reduced ejection fraction (HFrEF): 23 ± 1 to 116 ± 10; Ctrls: 22 ± 1 to 137 ± 5 W resulted in a similar rise in blood flow (HFrEF: 1525 ± 132 to 4216 ± 408; Ctrls: 1774 ± 161 to 4713 ± 448 mL min−1), oxygen uptake (HFrEF: 206 ± 24 to 586 ± 34; Ctrls: 252 ± 21 to 747 ± 89 mL min−1) and lactate efflux across the leg (HFrEF: 479 ± 122 to 4929 ± 1255; Ctrls: 537 ± 155 to 5776 ± 1010 mm min−1). Vascular resistance fell similarly in both groups with increasing exercise intensity (HFrEF: 66 ± 10 to 24 ± 3; Ctrls: 69 ± 12 to 24 ± 4 mmHg L−1 min−1). Incremental KE exercise also revealed similar haemodynamic and metabolic responses in both Ctrls and patients.
Conclusion
Although assessed in a relatively small cohort, these data reveal that, when compared with well‐matched healthy Ctrls, alterations in peripheral haemodynamics and skeletal muscle metabolism during exercise may not be an obligatory accompaniment to HFrEF.
This paper summarizes and discusses the limited statistically significant, currently available, experimental data for the tensile strength of individual nanotubes of any sort. Only three such data ...sets currently exist: two for multi-wall carbon nanotubes and one for multi-wall WS
2 nanotubes. It is shown here that Weibull–Poisson statistics accurately fits all strength data sets and thus seems to apply at the nano-scale as well as it does at the micro- and macro-scales. The significance and trends of the Weibull shape and scale parameters, and their relation to the specific structural features of the different nanotubes, are discussed in each case. More recent fracture analyses are also discussed and, in that context, the role of defects in quasi-perfect structures in relation to the theoretical strength is examined.
Abstract A series of novel lanthanide β‐diketonate coordination compounds containing the ancillary ligand bis(diphenylphosphino) oxide (dppeO 2 ) have been synthesized, characterized, and studied ...spectroscopically. The compounds of formulas Ln(β‐dik) 3 (dppeO 2 ), where Ln: Eu and Gd and β‐dik ligands as tta ( Ln‐1 ), btf ( Ln‐2 ), bzac ( Ln‐5 ) and tfac ( Ln‐4 ), and Ln 2 (β‐dik) 6 (dppeO 2 ) with ligand dbm ( Ln‐3 ) and fod ( Ln‐6 ). Their photophysical properties were investigated from the Judd‐Ofelt intensity parameters ( ), radiative ( ) and non‐radiative ( ) rates, intrinsic ( ) and overall ( ) quantum yields, and CIE (x,y) color coordinates. The Eu‐5 and Eu‐6 compounds have the first excited triplet states T 1 (around 18802 and 18976 cm −1 , respectively) almost resonant with the Eu 3+ 5 D 0 emission level, whereas the complexes Eu‐1 , Eu‐2 , Eu‐3 , and Eu‐4 exhibited higher T 1 energies. The values were predominantly driven by the intensity parameter , suggesting more pronounced angular changes in the first coordination sphere of the Eu 3+ ion. The values also exhibited significant changes with the β‐diketonate ligands. Eu‐1 showed the highest value of (60 %), indicating a more efficient intramolecular energy transfer process. On the other hand, Eu‐5 and Eu‐6 compounds showed values equal to 18.7 % and 16.5 %, respectively, which indicates the presence of luminescence quencher channels.
Thousands of genomic regions have been associated with heritable human diseases, but attempts to elucidate biological mechanisms are impeded by an inability to discern which genomic positions are ...functionally important. Evolutionary constraint is a powerful predictor of function, agnostic to cell type or disease mechanism. Single-base phyloP scores from 240 mammals identified 3.3% of the human genome as significantly constrained and likely functional. We compared phyloP scores to genome annotation, association studies, copy-number variation, clinical genetics findings, and cancer data. Constrained positions are enriched for variants that explain common disease heritability more than other functional annotations. Our results improve variant annotation but also highlight that the regulatory landscape of the human genome still needs to be further explored and linked to disease.
Loss-of-function variants within the gene locus encoding protein tyrosine phosphatase non-receptor type 2 (PTPN2) are associated with increased risk for Crohn's disease (CD). A disturbed regulation ...of T helper (Th) cell responses causing loss of tolerance against self- or commensal-derived antigens and an altered intestinal microbiota plays a pivotal role in CD pathogenesis. Loss of PTPN2 in the T-cell compartment causes enhanced induction of Th1 and Th17 cells, but impaired induction of regulatory T cells (Tregs) in several mouse colitis models, namely acute and chronic dextran sodium sulfate colitis, and T-cell transfer colitis models. This results in increased susceptibility to intestinal inflammation and intestinal dysbiosis which is comparable with that observed in CD patients. We detected inflammatory infiltrates in liver, kidney, and skin and elevated autoantibody levels indicating systemic loss of tolerance in PTPN2-deficient animals. CD patients featuring a loss-of-function PTPN2 variant exhibit enhanced Th1 and Th17 cell, but reduced Treg markers when compared with PTPN2 wild-type patients in serum and intestinal tissue samples. Our data demonstrate that dysfunction of PTPN2 results in aberrant T-cell differentiation and intestinal dysbiosis similar to those observed in human CD. Our findings indicate a novel and crucial role for PTPN2 in chronic intestinal inflammation.
Report of a National Conference on Donation after Cardiac Death Bernat, J.L.; D'Alessandro, A.M.; Port, F.K. ...
American journal of transplantation,
February 2006, 2006-Feb, 2006-02-00, 20060201, Letnik:
6, Številka:
2
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
A national conference on organ donation after cardiac death (DCD) was convened to expand the practice of DCD in the continuum of quality end‐of‐life care.
This national conference affirmed the ...ethical propriety of DCD as not violating the dead donor rule. Further, by new developments not previously reported, the conference resolved controversy regarding the period of circulatory cessation that determines death and allows administration of pre‐recovery pharmacologic agents, it established conditions of DCD eligibility, it presented current data regarding the successful transplantation of organs from DCD, it proposed a new framework of data reporting regarding ischemic events, it made specific recommendations to agencies and organizations to remove barriers to DCD, it brought guidance regarding organ allocation and the process of informed consent and it set an action plan to address media issues.
When a consensual decision is made to withdraw life support by the attending physician and patient or by the attending physician and a family member or surrogate (particularly in an intensive care unit), a routine opportunity for DCD should be available to honor the deceased donor's wishes in every donor service area (DSA) of the United States.
Abstract
We present deep
g
- and
r
-band Magellan/Megacam photometry of two dwarf galaxy candidates discovered in the Dark Energy Survey (DES), Grus
i
and Indus
ii
(DES J2038–4609). For the case of ...Grus
i
, we resolved the main sequence turn-off (MSTO) and ∼2 mags below it. The MSTO can be seen at
g
0
∼ 24 with a photometric uncertainty of 0.03 mag. We show Grus
i
to be consistent with an old, metal-poor (∼13.3 Gyr, Fe/H ∼ −1.9) dwarf galaxy. We derive updated distance and structural parameters for Grus
i
using this deep, uniform, wide-field data set. We find an azimuthally-averaged halflight radius more than two times larger (∼151
+21
−31
pc; ∼
4
.′
16
−
0.74
+
0.54
) and an absolute
V
-band magnitude ∼−4.1 that is ∼1 magnitude brighter than previous studies. We obtain updated distance, ellipticity, and centroid parameters that are in agreement with other studies within uncertainties. Although our photometry of Indus
ii
is ∼2–3 magnitudes deeper than the DES Y1 public release, we find no coherent stellar population at its reported location. The original detection was located in an incomplete region of sky in the DES Y2Q1 data set and was flagged due to potential blue horizontal branch member stars. The best-fit isochrone parameters are physically inconsistent with both dwarf galaxies and globular clusters. We conclude that Indus
ii
is likely a false positive, flagged due to a chance alignment of stars along the line of sight.
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