Abstract
1
T
-TaS
2
undergoes successive phase transitions upon cooling and eventually enters an insulating state of mysterious origin. Some consider this state to be a band insulator with interlayer ...stacking order, yet others attribute it to Mott physics that support a quantum spin liquid state. Here, we determine the electronic and structural properties of 1
T
-TaS
2
using angle-resolved photoemission spectroscopy and X-Ray diffraction. At low temperatures, the 2π/2c-periodic band dispersion, along with half-integer-indexed diffraction peaks along the
c
axis, unambiguously indicates that the ground state of 1
T
-TaS
2
is a band insulator with interlayer dimerization. Upon heating, however, the system undergoes a transition into a Mott insulating state, which only exists in a narrow temperature window. Our results refute the idea of searching for quantum magnetism in 1
T
-TaS
2
only at low temperatures, and highlight the competition between on-site Coulomb repulsion and interlayer hopping as a crucial aspect for understanding the material’s electronic properties.
We report the observation of new properties of primary cosmic rays He, C, and O measured in the rigidity (momentum/charge) range 2 GV to 3 TV with 90×10^{6} helium, 8.4×10^{6} carbon, and 7.0×10^{6} ...oxygen nuclei collected by the Alpha Magnetic Spectrometer (AMS) during the first five years of operation. Above 60 GV, these three spectra have identical rigidity dependence. They all deviate from a single power law above 200 GV and harden in an identical way.
We report on the observation of new properties of secondary cosmic rays Li, Be, and B measured in the rigidity (momentum per unit charge) range 1.9 GV to 3.3 TV with a total of 5.4×10^{6} nuclei ...collected by AMS during the first five years of operation aboard the International Space Station. The Li and B fluxes have an identical rigidity dependence above 7 GV and all three fluxes have an identical rigidity dependence above 30 GV with the Li/Be flux ratio of 2.0±0.1. The three fluxes deviate from a single power law above 200 GV in an identical way. This behavior of secondary cosmic rays has also been observed in the AMS measurement of primary cosmic rays He, C, and O but the rigidity dependences of primary cosmic rays and of secondary cosmic rays are distinctly different. In particular, above 200 GV, the secondary cosmic rays harden more than the primary cosmic rays.
AbstractGlued laminated bamboo (glubam) is a type of engineered bamboo that resembles timber-based glued laminated lumber (glulam). The glubam components are made by laminating 20- to 40-mm-thick ...engineered bamboo boards; thus, the performance is determined by the quality and properties of the laminated boards. A comprehensive testing program was conducted on typical engineered bamboo boards. The experiments were performed according to the general requirements given by international standards; however, the size of specimens and loading jigs were redesigned according to the modular thickness of typical bamboo boards. Mechanical behaviors and failure modes of the specimens under 15 stress conditions are reported, along with the surface strain distribution recorded through digital image correlation (DIC). A simple design-oriented axial stress–strain model is proposed, and strength values, including the corresponding coefficient of variance (COV), are calculated and provided. A comparison of characteristic strength values between engineered bamboo and typical wood products is also given in this research.
Fast radio bursts (FRBs) are highly dispersed, millisecond-duration radio bursts1-3. Recent observations of a Galactic FRB4-8 suggest that at least some FRBs originate from magnetars, but the origin ...of cosmological FRBs is still not settled. Here we report the detection of1,863 bursts in 82 h over 54 days from the repeating source FRB 20201124A (ref.9). These observations show irregular short-time variation ofthe Faraday rotation measure (RM), which scrutinizes the density-weighted line-of-sight magnetic field strength, of individual bursts during the first 36 days, followed by a constant RM. We detected circular polarization in more than half of the burst sample, including one burst reaching a high fractional circular polarization of 75%. Oscillations in fractional linear and circular polarizations, as well as polarization angle as a function of wavelength, were detected. All of these features provide evidence for a complicated, dynamically evolving, magnetized immediate environment within about an astronomical unit (au; Earth-Sun distance) ofthe source. Our optical observations of its Milky-Way-sized, metal-rich host galaxy10-12 show a barred spiral, with the FRB source residing in a low-stellar-density interarm region at an intermediate galactocentric distance. This environment is inconsistent with a young magnetar engine formed during an extreme explosion of a massive star that resulted in a long gamma-ray burst or superluminous supernova.
Although copper is essential for plant growth and development and plays an important role in many physiological processes, excess copper, resulting from industrial development and population ...expansion in the recent decades, leads to environmental pollution and has been a cause of wide concern for the adverse effects on photosynthesis, metabolism and growth of plants.
The growth properties (e.g. fresh weight, root length, height), photosynthetic properties (e.g. gas exchange, chlorophyll a fluorescence, chlorophyll content) and the physiological index (e.g. activity of antioxidant enzymes and osmotic regulators) of Eichhornia crassipes were assessed under various Cu2+ concentrations in hydroponic experiments.
The growth of E. crassipes was negatively affected by Cu2+ treatments, especially at higher Cu2+ concentrations; the Cu2+ treatments resulted in decreased photosynthesis because of a decrease in leaf chlorophyll content and damage to PSII functions, except the oxygen‐evolving complex. The physiological tolerance of E. crassipes to Cu2+ relies on osmotic regulation, anti‐lipid peroxidation and improved antioxidant properties.
The results indicate that E. crassipes could be considered as a phytoremediation agent for Cu2+ pollution in aquatic environments. However, the benefit of E. crassipes for Cu2+ removal in a highly polluted aquatic environment will be limited, but it will be effective in remediating sites with low pollution (≤5 mg·l−1). The present results could provide not only a basis for understanding the effects of pollutants on photosynthesis in plants under heavy metal stress but also provide a basis for choosing plants for phytoremediation.
The photosynthetic rate and growth of E. crassipes is greatly affected by Cu2+ in aquatic cultivation, and the negative effect of Cu2+ on E. crassipes is dose‐dependent, but E. crassipes might adapt to moderate Cu2+ pollution (≤ 5 mg·L‐1) through osmotic regulation, anti‐lipid peroxidation, and the improvement of its antioxidant properties.
Summary
The aim of this study was to perform a head‐to‐head comparison of efficacy and safety profile between 60 mg denosumab (Den) subcutaneously (SC) per 6 months (Q6M) and 70 mg alendronate (Aln) ...orally per week (QW) for postmenopausal women with low bone mineral density. We searched electronic databases comparing efficacy and safety of Den SC Q6M and Aln QW in postmenopausal women. The primary outcomes of efficacy evaluation in included trials were incidence of clinical fracture in both groups and bone mineral density (BMD) at different skeletal sites. And adverse events (AEs), including incidence of neoplasms and infections, were considered as secondary outcomes. Following the instructions of ‘Cochrane Handbook for systematic Reviews of Interventions 5.0.2’, we identified eligible studies, evaluated the methodological quality and ed relevant data. Four heterogeneous randomised controlled trials (RCTs) involving 1942 women were identified. The results of review showed low evidence quality that supported the hypothesis the denosumab vs. alendronate could reduce risk of fracture OR (95% CI) 1.42 (0.84 to 2.40), 11 more women per 1000 (from 4 fewer to 36 more), p = 0.19 but the moderate to high quality evidence suggesting treatment with 60 mg Den SC Q6M was more effective for postmenopausal women in increasing BMD at distal radius (DR), total hip (TH), lumbar spine (LS), and femoral neck (FN). Hazards of neoplasms OR (95% CI) 1.10 (0.65 to 1.86), 3 more per 1000 (from 10 fewer to 24 more), p = 0.62 or infections OR (95% CI) 0.95 (0.79 to 1.15), 12 fewer per 1000 (from 53 fewer to 33 more,), p = 0.62 were appeared to be similar.Our review suggested within 1 year 60 mg Den SC Q6M treatment was more effective in increasing bone mass but could not reduce the fracture risk to a greater extent than 70 mg Aln QW therapy. Also the Den SC Q6M therapy did not increase the risks of neoplasms and infections compared with Aln QW.
Abstract
Charge ordered kagome lattices have been demonstrated to be intriguing platforms for studying the intertwining of topology, correlation, and magnetism. The recently discovered charge ordered ...kagome material ScV
6
Sn
6
does not feature a magnetic groundstate or excitations, thus it is often regarded as a conventional paramagnet. Here, using advanced muon-spin rotation spectroscopy, we uncover an unexpected hidden magnetism of the charge order. We observe an enhancement of the internal field width sensed by the muon ensemble, which takes place within the charge ordered state. More importantly, the muon spin relaxation rate below the charge ordering temperature is substantially enhanced by applying an external magnetic field. Taken together with the hidden magnetism found in
A
V
3
Sb
5
(
A
= K, Rb, Cs) and FeGe kagome systems, our results suggest ubiqitous time-reversal symmetry-breaking in charge ordered kagome lattices.
We report the observation of new properties of primary iron (Fe) cosmic rays in the rigidity range 2.65 GV to 3.0 TV with 0.62×10^{6} iron nuclei collected by the Alpha Magnetic Spectrometer ...experiment on the International Space Station. Above 80.5 GV the rigidity dependence of the cosmic ray Fe flux is identical to the rigidity dependence of the primary cosmic ray He, C, and O fluxes, with the Fe/O flux ratio being constant at 0.155±0.006. This shows that unexpectedly Fe and He, C, and O belong to the same class of primary cosmic rays which is different from the primary cosmic rays Ne, Mg, and Si class.
Summary
The present meta-analysis aimed to evaluate the middle-term efficacy of bisphosphonates on maintaining periprosthetic bone mass after joint arthroplasty and the potential influential factors. ...It was found that the protective effect of bisphosphonates, probably modified by its generation and the prosthesis location, could persist in a middle-term follow-up after surgery and after drug discontinuation.
Introduction
A previous meta-analysis of 6 RCTs with follow-up of 12 months suggested that bisphosphonates (BPs) could prevent bone loss after arthroplasty up to 6 months. Our meta-analysis based on 14 RCTs involving 671 patients with follow-up up to 72 months aimed to evaluate the middle-term efficacy of BPs, understand the sources of heterogeneity, and comprehensively identify the potential influential factors.
Methods
Electronic databases searching and hand searching of conference proceedings were conducted. We evaluated the methodological quality and abstracted relevant data. With fixed effect model we calculated the weighted mean differences to evaluate bone mineral density at different time points. We also conducted a systematic review for BP-related adverse effects.
Results
The significantly less periprosthetic bone loss occurred in the BP-treated group than in the control group at 3, 6, and 12 months, and between 24 and 72 months after the index surgery. The protective effect persisted during 18 to 70 months after discontinuation of BPs. The heterogeneity was minimized with the separation of hip and knee trials during the analysis. The efficacy was more potent for the second and the third generation of BPs than the first generation. None of the trials noted serious or fatal adverse effects related to BPs.
Conclusions
The overall moderate evidence from the RCTs confirmed the significantly short-term and middle-term efficacy of BPs on periprosthetic bone loss after joint arthroplasty. To obtain a better efficacy, the second and the third generation of BPs may be the choice.
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