Control of the radiative properties of functional molecules near metals is a key issue in nano-optics, and is particularly important in the fields of energy transfer and light manipulation at the ...nanoscale and the development of plasmonic devices. Despite the various vibronic transitions (S1 (vvariant prime) arrow right S0 (v)) available for frequency tuning of fluorescence, the molecular emissions near metals reported to date have been subject to Kasha's rule, with radiative decay from the lowest excited state (S1 (0)) (refs 6-10). Here, we show resonant hot electroluminescence arising directly from higher vibronic levels of the singlet excited state (S1 (vvariant prime > 0)) for porphyrin molecules confined inside a nanocavity in a scanning tunnelling microscope, by spectrally tuning the frequency of plasmons. We also demonstrate the generation of unexpected upconversion electroluminescence. These observations suggest that the local nanocavity plasmons behave like a strong coherent optical source with tunable energy, and can be used to actively control the radiative channels of molecular emitters by means of intense resonance enhancement of both excitation and emission.
•Cellulose cleavage started at the temperature above 150°C.•Hemicelluloses removal could only reach to a certain level.•Severe degradation of cellulose occurred when hemicelluloses removal exceeded ...the certain level.•Allomorphs of cellulose conversion observed in the process of the pretreatment.
A systematic hydrothermal pretreatment of bamboo chips had been conducted with an aim to trace the cellulose degradation. The results showed that cellulose chain cleavage basically occurred when the temperature exceeded 150°C. A slightly higher DP (degree of polymerization) than starting material had been observed at low temperature pretreatment. Treatment at higher temperature (⩾170°C) caused severe cleavage of cellulose and therefore gave rise to low DP with more soluble species. DP of cellulose declined drastically without additional hemicelluloses dissolution when hemicelluloses removal reached to the limit level. Cellulose degradation under hydrothermal pretreatment generally followed the zero reaction kinetics with the activity energy of 121.0kJ/mol. Besides, the increase of cellulose crystalline index and the conversion of Iα–Iβ had also observed at the hydrothermal pretreatment.
The physical properties of 12 eclipsing binaries of M-type dwarfs with superflare activity are characterized by combining the ground-based spectroscopic measurements and the photometric light curves ...obtained by the Kepler Space Telescope. All of these binary systems have Algol-type orbital configurations. The primary components are mostly of the early M-type dwarfs (M0-M3). Even though the occurrence rate of large flares with energy >1034 erg of the EBs is less than the hyperflaring M dwarfs, the corresponding cumulative flare frequency is in general about a factor of 10 higher than the single M dwarfs with flare activity. This might be the consequence of magnetic interaction between the primary and secondary component of individual binaries. The slow rotators are not as active as the fast rotators, some of which display a possible eclipsing effect in their flare activity.
To examine the association between depression and impaired glucose regulation, newly diagnosed diabetes and previously diagnosed diabetes in middle-aged and elderly Chinese people, and whether ...depression was associated with different treatment regimens or durations of diabetes.
A cross-sectional study was performed among 229,047 adults living in the community aged ≥ 40 years from 25 centres in China. The self-reported depression rating scale Patient Health Questionnaire 9 (PHQ-9) was used to diagnose probable and sub-threshold depression. Glucose metabolism status was determined according to World Health Organization 1999 diagnostic criteria.
The numbers of participants with normal glucose regulation, impaired glucose regulation, newly diagnosed diabetes and previously diagnosed diabetes were 120,458, 59,512, 24,826 and 24,251, respectively. The prevalence of sub-threshold depression in the total sample of participants was 4.8% (4.8%, 4.8%, 4.4% and 5.6% from normal glucose regulation to previously diagnosed diabetes, respectively), and the prevalence of probable depression was 1.1% (1.1%, 1.0%, 0.9% and 1.8% from normal glucose regulation to previously diagnosed diabetes, respectively). Compared with participants with normal glucose regulation, those with previously diagnosed diabetes had increased odds of probable depression odds ratio (OR) = 1.61, 95% confidence interval (CI) 1.39-1.87 and sub-threshold depression (OR = 1.14, 95% CI 1.06-1.24), after adjustment for multiple confounding factors. Newly diagnosed diabetes or impaired glucose regulation was not associated with depression. Among those with previously diagnosed diabetes, insulin treatment was associated with greater odds of depression compared with no treatment or oral anti-diabetic medicine.
Previously diagnosed diabetes, but not newly diagnosed diabetes or impaired glucose regulation, was associated with a higher prevalence of depression. Patients receiving insulin were more likely to have depression than those not receiving treatment or being treated with oral anti-diabetic medicine.
The first fossil chordates are found in deposits from the Cambrian period (545-490 million years ago), but their earliest record is exceptionally sporadic and is often controversial. Accordingly, it ...has been difficult to construct a coherent phylogenetic synthesis for the basal chordates. Until now, the available soft-bodied remains have consisted almost entirely of cephalochordate-like animals from Burgess Shale-type faunas.
Body mass index (BMI) has been associated with the risk of oesophageal cancer. But the influence of BMI on postoperative complication and prognosis has always been controversial.
In total, 2031 ...consecutive patients who underwent oesophagectomy between 1998 and 2008 were classified according to Asian-specific BMI (kg m(-2)) cutoff values. The impact of BMI on overall survival (OS) was estimated using the Kaplan-Meier method and Cox proportional hazard models. We performed a meta-analysis to examine the association of BMI with OS and postoperative complication.
Patients with higher BMI had more postoperative complication (P=0.002), such as anastomotic leakage (P=0.016) and cardiovascular diseases (P<0.001), but less incidence of chylous leakage (P=0.010). Logistic regression analysis showed that BMI (P=0.005) was a confounding factor associated with postoperative complication. Multivariate analysis showed that overweight and obese patients had a more favourable survival than normal weight patients (HR (hazard ratio) = 0.80, 95% CI (confidence interval): 0.70-0.92, P=0.001). Subgroup analysis showed that the association with higher BMI and increased OS was observed in patients with oesophageal squamous cell carcinoma (ESCC) (P<0.001), oesophageal adenocarcinoma (EA) (P=0.034), never-smoking (P=0.035), ever-smoking (P=0.035), never alcohol consumption (P=0.005), weight loss (P=0.003) and advanced pathological stage (P<0.001). The meta-analysis further corroborated that higher BMI was associated with increased complication of anastomotic leakage (RR (risk ratio)=1.04, 95% CI: 1.02-1.06, P=0.001), wound infection (RR=1.03, 95% CI: 1.00-1.05, P=0.031) and cardiovascular diseases (RR=1.02, 95% CI: 1.00-1.05, P=0.039), but decreased incidence of chylous leakage (RR=0.98, 95% CI: 0.96-0.99, P<0.001). In addition, high BMI could significantly improved OS (HR=0.78, 95% CI: 0.71-0.85, P<0.001).
Preoperative BMI was an independent prognostic factor for survival, and strongly associated with postoperative complications in oesophageal cancer.
Spectrum-energy correlations of peak energy with total prompt γ-ray emission energies, namely E p , i − E iso , E p , i − E γ , and E p , i − L p , had been studied for long gamma-ray bursts (GRBs) ...previously by many authors. These energy correlations were proposed to measure the universe and classify GRBs as useful probes. However, most of these relations were built by non-Swift bursts. The spectrum-energy correlations of short bursts have not been systematically established yet; in particular, how the newly found GRB170817A matches these energy relations is unknown to date. We will first refresh the three spectrum-energy relations of Swift/BAT and Fermi/GBM long bursts and build the corresponding relations of short bursts. Then, we confirm whether they are commonly available as a discriminator of short and long GRBs. Some potential violators to these relations will be investigated. Combining with the plane of peak energy versus fluence, we select 31 short and 252 long GRBs with well-measured peak energy and redshift to study the issue of GRB classifications connected with the above energy relations statistically. We find that the three energy relations do exist in our new GRB samples and they are marginally consistent with some previous results. We report for the first time that short GRBs hold the three corresponding energy relations having the consistent power-law indices with long GRBs. It is found that these energy relations can be adopted to discriminate GRBs successfully if they are put in the peak energy versus fluence plane. Excitingly, we point out that GRB090510 matches the energy relations of E p , i − E iso and E p , i − L p , but violates the E p , i − E γ relation. More excitingly, we find that GRB170817A is an outlier to all the three energy correlations.
The process e+e- → Λ Λ ¯ is studied using data samples at √s = 2.2324, 2.400, 2.800 and 3.080 GeV collected with the BESIII detector operating at the BEPCII collider. The Born cross section is ...measured at √s=2.2324 GeV, which is 1.0 MeV above the Λ Λ ¯ mass threshold, to be 305±$45_{-36}^{+66}$ pb, where the first uncertainty is statistical and the second systematic. The substantial cross section near threshold is significantly larger than that expected from theory, which predicts the cross section to vanish at threshold. The Born cross sections at √s=2.400, 2.800 and 3.080 GeV are measured and found to be consistent with previous experimental results, but with improved precision. Finally, the corresponding effective electromagnetic form factors of Λ are deduced.
In order to improve the particle identification capability, the Beijing Spectrometer (BESIII) collaboration has upgraded the End-cap Time-Of-Flight detector (ETOF) based on Multi-gap Resistive Plate ...Chamber (MRPC) technology. In this paper, the design and engineering development of each part of the project are reported. There are 72 MRPC modules, forming 2 rings. Adjacent modules are staggered placed to avoid dead regions. Each MRPC module contains 12-layer thin gaps to get fast signals with high efficiency and 12 strips to readout the induced signals from two ends, effectively reducing the timing uncertainties from the scattering and positioning. Also, the analog–digital conversion is done near the MRPC and only the digital signals are transferred through thin coax cables, ensuring good signal-to-noise ratio. The complex electromagnetic noises in the BESIII colliding area are well shielded to protect the tiny signals from the MRPC. After careful correction and calibration, the total time resolution of upgraded ETOF system is 65ps.
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