Abstract
We present observations of the carbon-rich protoplanetary nebula CRL 2688 made with the Institut de Radioastronomie Millimétrique 30 m telescope in the 3 and 2 mm bands. In total, 196 ...transition lines belonging to 38 molecular species and isotopologues are detected, among which, to the best of our knowledge, 153 transition lines and 13 species are the first reported for this object. Additionally, in order to contribute to future research, we have collected observational data on the molecular lines of CRL 2688 from the literature and compiled them into a single unified catalog. We find that the molecular abundance of CRL 2688 cannot be explained by the standard model of a circumstellar envelope. The implications of metal-bearing molecules on circumstellar chemistry are discussed.
Abstract
Water fountains (WFs) are thought to be objects in the morphological evolution of the circumstellar envelopes of low- and intermediate-mass evolved stars, transitioning from spherically ...symmetric to asymmetric shapes. We used databases of circumstellar 1612 MHz OH and 22.235 GHz H
2
O maser sources to search for new WF candidates using the criterion of a larger velocity range of the H
2
O maser emission compared to that of the OH maser emission. Thus, it is in principle possible to identify WFs with H
2
O velocity ranges smaller than those for the previously known WFs. For the OH maser line, we analyzed database entries of 8474 observations from 2195 sources, and 6085 observations from 3642 sources for the H
2
O maser line. After a close examination of the velocity ranges and line profiles, we identified 11 sources that meet the criterion mentioned above. We examined the IRAS colors of the selected sources and found that two of them (IRAS 19069+0916 and IRAS 19319+2214) are in the color region for post-AGB stars. We find that the maser velocity criterion can discover other astrophysically interesting objects than just WFs. Such objects may include peculiar planetary nebulae with maser emissions and stellar merger remnants.
Abstract
It has been more than 30 years since the enigmatic 21
μ
m emission feature was first discovered in protoplanetary nebulae (PPNs). Although dozens of different dust carrier candidates have ...been proposed, there is as yet no widely accepted one. We present the results of molecular observations toward 21
μ
m objects using the 10 m Submillimeter Telescope of Arizona Radio Observatory in the 1.3 mm band and the 13.7 m telescope of Purple Mountain Observatory in the 3 mm band, aiming to investigate whether the gas-phase environments of these unusual sources have some peculiarities compared to normal PPNs. We detect 31 emission lines belonging to seven different molecular species, most of which are the first detection in 21
μ
m PPNs. The observations provide clues to the identification of the 21
μ
m feature. We report a correlation study between the fractional abundance of gas-phase molecules and the strengths of the 21
μ
m emission. Our study shows that, given the small sample size, the 21
μ
m feature has weak or no correlations with the gas-phase molecules. Future radio observations of high spatial and spectral resolution toward a large sample are desirable to elucidate the 21
μ
m emission phenomena.
Approximately 10% of bone fractures do not heal satisfactorily, leading to significant clinical and socioeconomic implications. Recently, the role of macrophages in regulating bone marrow stem cell ...(BMSC) differentiation through the osteogenic pathway during fracture healing has attracted much attention.
: The tibial monocortical defect model was employed to determine the critical role of macrophage scavenger receptor 1 (MSR1) during intramembranous ossification (IO)
. The potential functions and mechanisms of MSR1 were explored in a co-culture system of bone marrow-derived macrophages (BMDMs), RAW264.7 cells, and BMSCs using qPCR, Western blotting, immunofluorescence, and RNA sequencing.
: In this study, using the tibial monocortical defect model, we observed delayed IO in MSR1 knockout (KO) mice compared to MSR1 wild-type (WT) mice. Furthermore, macrophage MSR1 mediated PI3K/AKT/GSK3β/β-catenin signaling increased ability to promote osteogenic differentiation of BMSCs in the co-culture system. We also identified proliferator-activated receptor gamma coactivator 1-alpha (PGC1α) as the target gene for macrophage MSR1-activated PI3K/AKT/GSK3β/β-catenin pathway in the co-culture system that facilitated M2-like polarization by enhancing mitochondrial oxidative phosphorylation.
: Our findings revealed a previously unrecognized function of MSR1 in macrophages during fracture repair. Targeting MSR1 might, therefore, be a new therapeutic strategy for fracture repair.
• Betanin has been widely used as an additive for many centuries, and its use has increased because of its market application as an additive, high free radical scavenging activity, and safety, ...health-promoting properties.
• The main source of betanin is red beet, but many factors notably affect the yield of betanin from red beets. Betanin is not produced in cereal grains. Thus, developing biofortified crops with betanin is another alternative to health-promoting food additives.
• Here, rice endosperm was bioengineered for betanin biosynthesis by introducing three synthetic genes (meloS, BvDODA1S, and BvCYP76AD1S). The overexpression of these genes driven by rice endosperm-specific promoter established the betanin biosynthetic pathways in the endosperm, resulting in new types of germplasm – ‘Betanin Rice’ (BR). The BR grains were enriched with betanin and had relatively high antioxidant activity.
• Our results proved that betanin can be biosynthesized de novo in rice endosperm by introducing three genes in the committed betanin biosynthetic pathway. The betanin-fortified rice in this study can be used as a functional grain to promote health and as a raw material to process dietary supplements.
Abstract
We present
and
maps of six nearby star-forming galaxies, NGC 253, NGC 1068, IC 342, M82, M83, and NGC 6946, obtained with the James Clerk Maxwell Telescope as part of the MALATANG survey. ...All galaxies were mapped in the central 2′ × 2′ region at 14″ (FWHM) resolution (corresponding to linear scales of ∼0.2–1.0 kpc). The
L
IR
–
L
′
dense
relation, where the dense gas is traced by the
and the
emission, measured in our sample of spatially resolved galaxies is found to follow the linear correlation established globally in galaxies within the scatter. We find that the luminosity ratio,
L
IR
/
L
′
dense
, shows systematic variations with
L
IR
within individual spatially resolved galaxies, whereas the galaxy-integrated ratios vary little. A rising trend is also found between
L
IR
/
L
′
dense
ratio and the warm-dust temperature gauged by the 70
μ
m/100
μ
m flux ratio. We find that the luminosity ratios of IR/HCN (4–3) and IR/HCO
+
(4–3), which can be taken as a proxy for the star formation efficiency (SFE) in the dense molecular gas (SFE
dense
), appear to be nearly independent of the dense gas fraction (
f
dense
) for our sample of galaxies. The SFE of the total molecular gas (SFE
mol
) is found to increase substantially with
f
dense
when combining our data with those on local (ultra)luminous infrared galaxies and high-
z
quasars. The mean
line ratio measured for the six targeted galaxies is 0.9 ± 0.6. No significant correlation is found for the
ratio with the star formation rate as traced by
L
IR
, nor with the warm-dust temperature, for the different populations of galaxies.
Stress, herd transfer, and food changes experienced by nursery and fattening pigs can lead to reduced performance, reduced digestion and absorption, and impaired intestinal health. Given the role of ...essential oils in relieving stress and improving animal welfare, we hypothesized that essential oils may improve pig performance via promoting gut health and gut homeostasis laid by EOs supplementation during nursery continuously impacts performance in fattening pigs.
A total of 100 piglets (Landrace × Large White; weighted 8.08 ± 0.34 kg, weaned at d 28) were randomly selected and divided into 2 treatments: (1) basal diet (Con); (2) basal diet supplement with 0.1% complex essential oils (CEO). The experiment period was 42 days. Then weaned piglets' growth performance and indications of intestinal health were assessed. Compared to the Con group, dietary supplemented CEO enhanced BW at 14 d (P < 0.05), and increased ADG during 1 ~ 14 d and 1 ~ 42 d (P < 0.05). Furthermore, CEO group had lower FCR during 1 ~ 42 d (P < 0.05). The CEO group also showed higher VH and VH:CD in duodenum and ileum (P < 0.05). Additionally, dietary CEO supplementation improved gut barrier function, as manifested by increased the mRNA expression of tight-junction protein and decreased serum DAO, ET and D-LA levels (P < 0.05). Finally, CEO supplementation alleviated gut inflammation, increased the activity of digestive enzymes. Importantly, piglets supplemented with CEOs during nursery also had better performance during fattening, suggesting that the establishment of intestinal health will also continuously affect subsequent digestion and absorption capacity. In short, dietary supplemented CEO improved performance and gut health via modulating increased intestine absorptive area, barrier integrity, digestive enzyme activity, and attenuating intestine inflammation. Meanwhile, essential oil supplementation during the nursery period also had a favorable effect on the performance of growing pigs.
Therefore, the strategy of adding CEO to pig diets as a growth promoter and enhancing intestinal health is feasible.
Context.
IRAS 19312+1950 is an isolated infrared source that exhibits a characteristic quasi-point-symmetric morphology in the near-and mid-infrared images and is also very bright in molecular radio ...lines. Because of its unique observational characteristics, various observational studies have been conducted and several hypotheses have been proposed regarding its origin, which is still unclear. So far, it has been suggested that it could be a peculiar evolved star, a young stellar object, or even a red nova remnant. Regardless of which type of object it is ultimately classified as, IRAS 19312+1950 is exceptionally bright in the infrared and molecular radio lines and therefore will undoubtedly be crucial as a prototype of this kind of object having a peculiar nature or unusual evolutionary phase.
Aims.
This study aims to reveal the molecular composition of the central part of IRAS 19312+1950 by performing an unbiased molecular radio line survey and discussing the origin of the object from a molecular chemical point of view.
Methods.
We carried out a spectral line survey with the Institut de Radioastronomie Millimtrique 30 m telescope towards the centre of IRAS 19312+1950 in the 3 and 1.3 mm windows with a frequency coverage of 83.9–91.8 and 218.2–226.0 GHz, respectively.
Results.
In total, 28 transition lines of 22 molecular species and those isotopologues are detected towards IRAS 19312+1950, some of which exhibit a broad and a narrow component. Seventeen thermal lines and one maser line are newly detected. The molecular species of C
17
O,
30
SiO, HN
13
C, HC
18
O
+
, H
2
CO, and c-C
3
H
2
are detected for the first time in this object. We calculated the optical depths of the transition lines of
13
CO, C
18
O, HCN, H
13
CN, and C
2
H, and determined the rotational temperatures, column densities, and fractional abundances of the detected molecules. We got the isotopic ratios of
12
C/
13
C,
14
N/
15
N,
16
O/
18
O,
16
O/
17
O,
18
O/
17
O,
28
Si/
30
Si, and
29
Si/
30
Si in IRAS 19312+1950 and the values were compared to those of evolved stars, red novae, young stellar objects, and the Sun. The intensities of the molecular radio lines of IRAS 19312+1950 were compared with those of different categories of objects, indicating that the spectral pattern of the broad-line region is similar to that of a red nova or a low-mass young stellar object, while the narrow-line region behaves like an envelope of the asymptotic giant branch star.
Conclusions.
Our results, in combination with previous studies, favour the hypothesis that IRAS 19312+1950 might be a red nova remnant, in which the progenitors that merged to become a red nova may have contained at least two evolved stars with oxygen-rich and carbon-rich chemistry, respectively.
Active Lamb wave detection is an effective and simple monitoring method for structural health monitoring (SHM). Piezoelectric lead zirconate titanate (PZT) ceramics are most commonly used as ...transducers to excite and receive Lamb wave. However, due to their hardness, thickness and brittleness, PZT ceramics are severely limited in detecting damage on curved surface structures. Herein, we report that flexible PZT film sensor is an excellent candidate for receiving Lamb wave used in Lamb wave-based SHM of aircraft. An improved piezoelectric coefficient d33 (~130 pm V−1) is obtained in epitaxial PZT films grown on flexible inorganic mica substrates via van der Waals heteroepitaxy. Superior stable ferroelectricity and piezoelectricity retain in flexible PZT film after bending 104 cycles under a radius of 8 mm. As proven by experiment and simulation, flexible PZT film is demonstrated as an ultrasonic sensor with high sensitivity to be bonded on the curved aluminum plate for Lamb wave-based damage monitoring. Our work demonstrates that flexible PZT films have enormous potential for real-time light-weight and high-sensitivity receiver sensors for the SHM of aging aircraft.
Antiglomerular basement membrane (anti-GBM) disease is associated with HLA-DRB1*1501 (the major predisposing genetic factor in the disease), with
3
as a nephritogenic T and B cell epitope. Although ...the cause of disease remains unclear, the association of infections with anti-GBM disease has been long suspected.
To investigate whether microbes might activate autoreactive T and B lymphocytes
molecular mimicry in anti-GBM disease, we used bioinformatic tools, including BLAST, SYFPEITHI, and ABCpred, for peptide searching and epitope prediction. We used sera from patients with anti-GBM disease to assess peptides recognized by antibodies, and immunized WKY rats and a humanized mouse model (HLA-DR15 transgenic mice) with each of the peptide candidates to assess pathogenicity.
On the basis of the critical motif, the bioinformatic approach identified 36 microbial peptides that mimic human
3
. Circulating antibodies in sera from patients with anti-GBM recognized nine of them. One peptide, B7, derived from
species, induced proteinuria, linear IgG deposition on the GBM, and crescent formation when injected into WKY rats. The antibodies to B7 also targeted human and rat
3
. B7 induced T cell activation from human
3
-immunized rats. T cell responses to B7 were detected in rats immunized by
lysate proteins or recombinant proteins. We confirmed B7's pathogenicity in HLA-DR15 transgenic mice that developed kidney injury similar to that observed in
3
-immunized mice.
Sera from patients with anti-GBM disease recognized microbial peptides identified through a bioinformatic approach, and a peptide from
induced experimental anti-GBM GN by T and B cell crossreactivity. These studies demonstrate that anti-GBM disease may be initiated by immunization with a microbial peptide.
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