Deviations from continuum mechanics are always expected in nanoscale structures. We investigate the validity of the plate idealization of ultrathin graphene by gaining insight into the response of ...chemical bonds to bending deformations. In the monolayer, a bond orbital model reveals the breakdown of the plate phenomenology. In the multilayer, objective molecular dynamics simulations identify the validity margin and the role of discreteness in the plate idealization. Our result has implications for a broad class of phenomena where the monolayer easily curves, and for the design of mass and force detection devices.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Background
The aim of this study was to investigate the prevalence of epidemiologic and physician‐diagnosed pollen‐induced AR (PiAR) in the grasslands of northern China and to study the impact of the ...intensity and time of pollen exposure on PiAR prevalence.
Methods
A multistage, clustered and proportionately stratified random sampling with a field interviewer‐administered survey study was performed together with skin prick tests (SPT) and measurements of the daily pollen count.
Results
A total of 6043 subjects completed the study, with a proportion of 32.4% epidemiologic AR and 18.5% PiAR. The prevalence was higher in males than females (19.6% vs 17.4%, P = .024), but no difference between the two major residential and ethnic groups (Han and Mongolian) was observed. Subjects from urban areas showed higher prevalence of PiAR than rural areas (23.1% vs 14.0%, P < .001). Most PiAR patients were sensitized to two or more pollens (79.4%) with artemisia, chenopodium, and humulus scandens being the most common pollen types, which were similarly found as the top three sensitizing pollen allergens by SPT. There were significant regional differences in the prevalence of epidemiologic AR (from 18.6% to 52.9%) and PiAR (from 10.5% to 31.4%) among the six areas investigated. PiAR symptoms were positively associated with pollen counts, temperature, and precipitation (P < .05), but negatively with wind speed and pressure P < .05).
Conclusion
Pollen‐induced AR (PiAR) prevalence in the investigated region is extremely high due to high seasonal pollen exposure, which was influenced by local environmental and climate conditions.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Abstract
The detection of the hyper-bright gamma-ray burst (GRB) 221009A enables us to explore the nature of the GRB emission and the origin of very high-energy gamma rays. We analyze the Fermi Large ...Area Telescope (Fermi-LAT) data of this burst and investigate the GeV–TeV emission in the framework of the external reverse-shock model. We show that the early ∼1–10 GeV emission can be explained by the external inverse-Compton mechanism via upscattering MeV gamma rays by electrons accelerated at the reverse shock, in addition to the synchrotron self-Compton component. The predicted early optical flux could have been brighter than that of the naked-eye GRB 080319B. We also show that proton synchrotron emission from accelerated ultrahigh-energy cosmic rays (UHECRs) is detectable and could potentially explain ≳TeV photons detected by LHAASO or constrain the UHECR acceleration mechanism. Our model suggests that the detection of
(
10
TeV
)
photons with energies up to ∼18 TeV is possible for reasonable models of the extragalactic background light without invoking new physics and predicts anticorrelations between MeV photons and TeV photons, which can be tested with the LHAASO data.
Aims.
Gamma-ray burst (GRB) 190829A (
z
= 0.0785) was detected by
Fermi
and
Swift
and also at very high energy (VHE) by the High-Energy Stereoscopic System (H.E.S.S.) telescopes. The prompt emission ...displayed two emission episodes separated by a quiescent gap of ∼40 s. We present the 10.4 m Gran Telescopio Canarias (GTC) observations of the afterglow of GRB 190829A and its underlying supernova. We also compare GRB 190829A to GRB 180728A, a GRB with similar behaviour, and discuss the implications on underlying physical mechanisms producing these two GRBs.
Methods.
We present multi-band photometric data along with spectroscopic follow-up observations taken with the 10.4 m GTC telescope. Together with the data from the prompt emission, the 10.4 m GTC data are used to understand the emission mechanisms and possible progenitor.
Results.
A detailed analysis of the multi-band observations of the afterglow requires the cooling frequency to pass between the optical and X-ray bands at early epochs. The afterglow then transitions to the underlying supernova (SN) 2019oyw, which dominates later on.
Conclusions.
Although the prompt emission temporal properties of GRB 190829A and GRB 180728A are similar, the two pulses are different in the spectral domain. We find that SN 2019oyw associated with GRB 190829A is powered by Ni decay and is a Type Ic-BL SN. The spectroscopic and photometric properties of this SN are consistent with those observed for SN 1998bw, but evolved earlier.
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FMFMET, NUK, UL, UM, UPUK
Summary
The China Health and Nutrition Survey (CHNS) began in 1989 with the goal of creating a multilevel method of data collection from individuals and households and their communities to understand ...how the wide‐ranging social and economic changes in China affect a wide array of nutrition and health‐related outcomes. Initiated with a partial sample in 1989, the full survey runs from 1991 to 2011, and this issue documents the CHNS history. The CHNS cohort includes new household formation and replacement communities and households; all household members are studied. Furthermore, in‐depth community data are collected. The sample began with eight provinces and added a ninth, Heilongjiang, in 1997 and three autonomous cities, Beijing, Shanghai, and Chongqing, in 2011. The in‐depth community contextual measures have allowed us to create a unique measure of urbanicity that captures major dimensions of modernization across all 288 communities currently in the CHNS sample. The standardized, validated urbanicity measure captures the changes in 12 dimensions: population density; economic activity; traditional markets; modern markets; transportation infrastructure; sanitation; communications; housing; education; diversity; health infrastructure; and social services. Each is based on numerous measures applicable to each dimension. They are used jointly and separately in hundreds of studies.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
We compile and analyze approximately 200 trigonometric parallaxes and proper motions of molecular masers associated with very young high-mass stars. Most of the measurements come from the BeSSeL ...Survey using the VLBA and the Japanese VERA project. These measurements strongly suggest that the Milky Way is a four-arm spiral, with some extra arm segments and spurs. Fitting log-periodic spirals to the locations of the masers, allowing for "kinks" in the spirals and using well-established arm tangencies in the fourth Galactic quadrant, allows us to significantly expand our view of the structure of the Milky Way. We present an updated model for its spiral structure and incorporate it into our previously published parallax-based distance-estimation program for sources associated with spiral arms. Modeling the three-dimensional space motions yields estimates of the distance to the Galactic center, , the circular rotation speed at the Sun's position, km s−1, and the nature of the rotation curve. Our data strongly constrain the full circular velocity of the Sun, km s−1, and its angular velocity, km s−1 kpc-1. Transforming the measured space motions to a Galactocentric frame which rotates with the Galaxy, we find non-circular velocity components typically 10 km s−1. However, near the Galactic bar and in a portion of the Perseus arm we find significantly larger non-circular motions. Young high-mass stars within 7 kpc of the Galactic center have a scale height of only 19 pc, and thus are well suited to define the Galactic plane. We find that the orientation of the plane is consistent with the IAU-defined plane to within 0 1, and that the Sun is offset toward the north Galactic pole by pc. Accounting for this offset places the central supermassive black hole, Sgr A*, in the midplane of the Galaxy. The measured motions perpendicular to the plane of the Galaxy limit precession of the plane to 4 km s−1 at the radius of the Sun. Using our improved Galactic parameters, we predict the Hulse-Taylor binary pulsar to be at a distance of 6.54 0.24 kpc, assuming its orbital decay from gravitational radiation follows general relativity.
ABSTRACT
Water balance is crucial for the growth and flowering of plants. However, the mechanisms by which flowers maintain water balance are poorly understood across different angiosperm branches.
...Here, we investigated 29 floral hydraulic and economic traits in 24 species from ANA grade, magnoliids, monocots, and eudicots. Our main objective was to compare differences in flower water use strategies between basal angiosperms (ANA grade and magnoliids) and derived group (monocots and eudicots).
We found that basal angiosperms had richer petal stomatal density, higher pedicel hydraulic diameter, and flower mass per area, but lower pedicel vessel wall reinforcement and epidermal cell thickness compared to monocots and eudicots. We also observed significant trade‐offs and coordination among different floral traits. Floral traits associated with reproduction, such as floral longevity and size, were strongly linked with physiological and anatomical traits.
Our results systematically reveal the variation in flower economic and hydraulic traits from different angiosperm branches, deepening understanding of flower water use strategies among these plant taxa. We conclude that basal angiosperms maintain water balance with high water supply, whereas monocots and eudicots maintain a more conservative water balance.
The flowers of monocots and eudicots tend to use water more conservatively than basal angiosperms, and their physiological and anatomical properties are strongly linked to traits associated with reproduction.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
n-Type Bi2Te3 thermoelectric materials were prepared by spark plasma sintering (SPS) using mechanically alloyed powders, and fine-grained Bi2Te3 bulks with preferred grain orientation have been ...fabricated by SPS as a hot-forging process. The effects of orientation degree and hot-forging temperature on thermoelectric properties were investigated. The electrical resistivity was reduced by increasing orientation degree, the Seebeck coefficient was increased by raising hot-forging temperature, and consequently the power factor was significantly increased from 2.1 mW/mK2, measured at 423 K, before hot-forging to 3.1 mW/mK2 after hot-forging at 733 K. The maximum ZT value after hot-forging at 733 K reached 1.18 measured at 423 K. This value was 20% higher than that before hot-forging, although the corresponding thermal conductivity was a little increased after hot-forging. The bending strength was greatly enhanced from 62 MPa to 120 MPa after the hot-forging.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The cross-talk of hepatocellular carcinoma (HCC) cells and abnormal metabolic signals in peritumoral microenvironment modifies our knowledge of hepatocarcinogenesis. As an indispensable modulator of ...various stresses, the clinical significance of heat-shock transcription factor-1 (HSF1) in HCC microenvironment has never been defined.
Hepatocellular carcinoma and matched peritumoral liver tissues (n=332) were semiquantitatively analysed for HSF1 expression, followed by correlation with clinicopathological parameters (patient outcomes). Moreover, the effects of HSF1 deficiency in L02 on monocarboxylate transporter-4 (MCT4) and HCC cells' colonisation and proliferation were investigated.
High expression of HSF1 in peritumoral tissue but not in HCC tissue was associated with poorer overall survival (OS) and time to recurrence (TTR), especially early recurrence (ER), which was further reconfirmed in validation cohort. Multivariate analysis showed that prognostic performance of peritumoral HSF1 was independent of other clinicopathological factors (hazard ratio for OS=2.60, P=0.002, for TTR=2.52, P<0.001). Notably, downregulation of HSF1 in L02 decreased MCT4 expression significantly. The supernatant from L02-shRNA-HSF1 in hypoxia, NOT normoxia condition, inhibited HCC cell colonisation and proliferation. Moreover, the combination of peritumoral HSF1 and MCT4 was the best predictor for ER and OS.
High peritumoral HSF1 expression can serve as a sensitive 'readout' for high-risk HCC ER, and could be a potential metabolic intervention target following curative resection.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Summary
This meta‐analysis aimed to evaluate the association between childhood and adolescent obesity and depression. We systematically searched PubMed, PsycInfo, EMBASE and Science Direct for ...studies that compared prevalence of depression and depressive symptoms in normal weight and obese children and adolescents. Observational studies were included if they reported body mass index and assessed depression by validated instruments or diagnostic interviews. Quality assessment was performed using the Newcastle–Ottawa scale. We used the random‐effect model to calculate the pooled odds ratios, standard mean differences (SMDs) and subgroup analysis. Findings for a total of 51,272 participants were pooled across 18 studies and examined. Our analyses demonstrated a positive association between childhood and adolescent obesity and depression (pooled odds ratio = 1.34, 95% confidence interval CI: 1.1–1.64, p = 0.005) and more severe depressive symptoms (SMD = 0.23, 95% CI: 0.025–0.44, p = 0.028) in the obese groups. Overweight subjects were not more likely to have either depression (pooled odds ratio = 1.16, 95% CI: 0.93–1.44, p = 0.19) or depressive symptoms (SMD = 0, 95% CI: −0.101 to 0.102, p = 0.997). Non‐Western and female obese subjects were significantly more likely to have depression and severe depressive symptoms (p < 0.05). In conclusion, obese children and adolescents are more likely to suffer from depression and depressive symptoms, with women and non‐Western people at higher risk.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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