Ambient backscatter communication (AmBC) enables a passive backscatter device to transmit information to a reader using ambient RF signals, and has emerged as a promising solution to green ...Internet-of-Things (IoT). Conventional AmBC receivers are interested in recovering the information from the ambient backscatter device (A-BD) only. In this paper, we propose a cooperative AmBC (CABC) system in which the reader recovers information not only from the A-BD, but also from the RF source. We first establish the system model for the CABC system from spread spectrum and spectrum sharing perspectives. Then, for flat fading channels, we derive the optimal maximum-likelihood (ML) detector, suboptimal linear detectors as well as successive interference-cancellation (SIC) based detectors. For frequency-selective fading channels, the system model for the CABC system over ambient orthogonal frequency division multiplexing carriers is proposed, upon which a low-complexity optimal ML detector is derived. For both kinds of channels, the bit-error-rate expressions for the proposed detectors are derived in closed forms. Finally, extensive numerical results have shown that, when the A-BD signal and the RF-source signal have equal symbol period, the proposed SIC-based detectors can achieve near-ML detection performance for typical application scenarios, and when the A-BD symbol period is longer than the RF-source symbol period, the existence of backscattered signal in the CABC system can enhance the ML detection performance of the RF-source signal, thanks to the beneficial effect of the backscatter link when the A-BD transmits at a lower rate than the RF source.
Lack of social support is a known predictor of the prognosis after acute myocardial infarction (AMI). Although as a common factor associated with social support, there are limited data on long-term ...prognostic impact of living status in young and middle-aged patients with AMI.
We analyzed data from the China Acute Myocardial Infarction (CAMI) Registry, consecutive AMI young and middle-aged patients admitted at 108 hospitals in China between January 2013 and September 2014 were included. Eligible patients were assigned to living alone and not living alone groups based on their living status. The primary endpoint was 2-year all-cause mortality. The secondary endpoints included in-hospital mortality and 2-year major adverse cardiac and cerebrovascular events (MACCEs; a composite of all-cause mortality, MI, or stroke). Multilevel logistic and multilevel Cox regression models were used to evaluate the effect of living status on short-term and long-term outcomes.
A total of 8307 consecutive AMI young and middle-aged patients were included, 192 (2.3%) patients were living alone. Of the analyzed patients, living alone was associated with 2-year all-cause mortality and MACCEs among all analyzed patients after multivariate adjustment (adjusted hazard ratio HR = 2.171 1.210-3.895, P = 0.009; adjusted HR = 2.169 1.395-3.370, P = 0.001), but not with poorer in-hospital mortality.
The analysis suggested that living alone was associated with both 2-year all-cause mortality and MACCEs in AMI young and middle-aged patients but did not show an extra effect on the in-hospital mortality after covariate adjustment.
Trial registration number: NCT01874691; Registered 31 October 2012.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Micro-scale MOFs with a persistent phosphorescence lifetime of 900 ms can be facilely synthesized by a fast precipitation process in aqueous solution. The
in situ
encapsulation of a dye into the MOF ...matrix can expressly tune the phosphorescence color from green to a rare example of red emission with a lifetime of 450 ms, highly enhancing the photoelectrocatalytic water splitting.
Micro-scale MOF host-guest with tunable phosphorescence and enhanced optoelectronic performance can be obtained by a facile and scalable precipitation process in aqueous solution.
Two-dimensional (2D) metal-organic framework (MOF) nanosheets have emerged as a new member of 2D nanomaterials for molecular sieving, energy conversion and storage, catalysis and biomedicine. In this ...paper, a highly dense assembly of porphyrin achievable in porphyrin-integrated MOF nanosheets induced by an ionic liquid is obtained by sonication exfoliation of its bulk crystals. The 2D layered structure MOF, BMI
2
Ca
3
(H
2
TCPP)
2
(μ
2
-OH
2
)
2
(H
2
O)
2
(
1
), was firstly prepared by using the ionic liquid assisted synthetic method (H
6
TCPP =
meso
-tetra(carboxyphenyl) porphyrin, BMI = 1-butyl-3-methylimidazolium). The laminated layers in
1
clearly indicate a weak interlayer non-covalent interaction but a strong metal-carboxylate bonding within the layers, which facilitates the exfoliation of
1
to form 2D MOF nanosheets (
1 NSs
). Powder X-ray diffraction (PXRD), high-resolution transmission electron microscopy (HR-TEM) and fast Fourier transform (FFT) patterns revealed that
1 NSs
could maintain their crystalline structure after exfoliation. These MOF nanosheets exhibited excellent aqueous dispersibility, biodegradability and high cytotoxicity under light irradiation against MCF-7 cells.
A facile fabrication of porphyrin-integrated MOF nanosheets as efficient photosensitizers for photodynamic therapy (PDT) is presented.
Herein, we report efficient single copper atom catalysts that consist of dense atomic Cu sites dispersed on a three-dimensional carbon matrix with highly enhanced mesoporous structures and improved ...active site accessibility (Cu-SA/NC(meso)). The ratio of +1 to +2 oxidation state of the Cu sites in the Cu-SA/NC(meso) catalysts can be controlled by varying the urea content in the adsorption precursor, and the activity for ORR increases with the addition of Cu1+ sites. The optimal Cu1+-SA/NC(meso)-7 catalyst with highly accessible Cu1+ sites exhibits superior ORR activity in alkaline media with a half-wave potential (E 1/2) of 0.898 V vs RHE, significantly exceeding the commercial Pt/C, along with high durability and enhanced methanol tolerance. Control experiments and theoretical calculations demonstrate that the superior ORR catalytic performance of Cu1+-SA/NC(meso)-7 catalyst is attributed to the atomically dispersed Cu1+ sites in catalyzing the reaction and the advantage of the introduced mesoporous structure in enhancing the mass transport.
The efficacy of cranberry (Vaccinium spp.) as adjuvant therapy in preventing urinary tract infections (UTIs) remains controversial. This study aims to update and determine cranberry effects as ...adjuvant therapy on the recurrence rate of UTIs in susceptible groups. According to PRISMA guidelines, we conducted a literature search in Web of Science, PubMed, Embase, Scopus, and the Cochrane Library from their inception dates to June 2021. We included articles with data on the incidence of UTIs in susceptible populations using cranberry-containing products. We then conducted a trial sequential analysis to control the risk of type I and type II errors. This meta-analysis included 23 trials with 3979 participants. We found that cranberry-based products intake can significantly reduce the incidence of UTIs in susceptible populations (risk ratio (RR) = 0.70; 95% confidence interval(CI): 0.59 ~ 0.83; P<0.01). We identified a relative risk reduction of 32%, 45% and 51% in women with recurrent UTIs (RR = 0.68; 95% CI: 0.56 ~ 0.81), children (RR = 0.55; 95% CI: 0.31 ~ 0.97) and patients using indwelling catheters (RR = 0.49; 95% CI: 0.33 ~ 0.73). Meanwhile, a relative risk reduction of 35% in people who use cranberry juice compared with those who use cranberry capsule or tablet was observed in the subgroup analysis (RR = 0.65; 95% CI: 0.54 ~ 0.77). The TSA result for the effects of cranberry intake and the decreased risk of UTIs in susceptible groups indicated that the effects were conclusive. In conclusion, our meta-analysis demonstrates that cranberry supplementation significantly reduced the risk of developing UTIs in susceptible populations. Cranberry can be considered as adjuvant therapy for preventing UTIs in susceptible populations. However, given the limitations of the included studies in this meta-analysis, the conclusion should be interpreted with caution.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A
bstract
We obtain the two-loop QCD corrections to the Higgs plus three-parton amplitudes with dimension-seven operators in Higgs effective field theory. This provides the two-loop S-matrix elements ...for Higgs plus one-jet production at the LHC with top-mass correction. We apply efficient unitarity plus IBP methods which are described in detail. We also study the color decomposition of the fermion cuts and find a connection between fundamental and adjoint representations which can be used to reduce non-planar to planar unitarity cuts in the Higgs to three-gluon amplitudes. We obtain final results in simple analytic form which exhibits intriguing hidden structures. The principle of maximal transcendentality is found to be satisfied for all results. The lower transcendentality parts also contain universal building blocks and can be written in compact analytic form, suggesting further hidden structures.
Background: A growing number of cohort studies revealed an inverse association between cheese intake and cardiovascular diseases, yet the causal relationship is unclear. Objective: To assess the ...causal relationship between cheese intake, and cardiovascular diseases and cardiovascular biomarkers. Methods: A two-sample Mendelian randomization (MR) analysis based on publicly available genome-wide association studies was employed to infer the causal relationship. The effect estimates were calculated using the random-effects inverse-variance-weighted method. Results: Cheese intake per standard deviation increase causally reduced the risks of type 2 diabetes (odds ratio (OR) = 0.46; 95% confidence interval (CI), 0.34–0.63; p = 1.02 × 10−6), heart failure (OR = 0.62; 95% CI, 0.49–0.79; p = 0.0001), coronary heart disease (OR = 0.65; 95% CI, 0.53–0.79; p = 2.01 × 10−5), hypertension (OR = 0.67; 95% CI, 0.53–0.84; p = 0.001), and ischemic stroke (OR = 0.76; 95% CI, 0.63–0.91; p = 0.003). Suggestive evidence of an inverse association between cheese intake and peripheral artery disease was also observed. No associations were observed for atrial fibrillation, cardiac death, pulmonary embolism, or transient ischemic attack. The better prognosis associated with cheese intake may be explained by lower body mass index (BMI; effect estimate = −0.58; 95% CI, from −0.88 to −0.27; p = 0.0002), waist circumference (effect estimate = −0.49; 95% CI, from −0.76 to −0.23; p = 0.0003), triglycerides (effect estimate = −0.33; 95% CI, from −0.50 to −0.17; p = 4.91 × 10−5), and fasting glucose (effect estimate = −0.20; 95% CI, from −0.33 to −0.07; p = 0.0003). There was suggestive evidence of a positive association between cheese intake and high-density lipoprotein. No influences were observed for blood pressure or inflammation biomarkers. Conclusions: This two-sample MR analysis found causally inverse associations between cheese intake and type 2 diabetes, heart failure, coronary heart disease, hypertension, and ischemic stroke.
This comparative study aims to identify a biocompatible and effective crosslinker for preparing gelatin sponges. Glutaraldehyde (GTA), genipin (GP), 1-ethyl-3-(3-dimethyl aminopropyl)carbodiimide ...(EDC), and microbial transglutaminase (mTG) were used as crosslinking agents. The physical properties of the prepared samples were characterized, and material degradation was studied in vitro with various proteases and in vivo through subcutaneous implantation of the sponges in rats. Adipose-derived stromal stem cells (ADSCs) were cultured and inoculated onto the scaffolds to compare the cellular biocompatibility of the sponges. Cellular seeding efficiency and digestion time of the sponges were also evaluated. Cellular viability and proliferation in scaffolds were analyzed by fluorescence staining and MTT assay. All the samples exhibited high porosity, good swelling ratio, and hydrolysis properties; however, material strength, hydrolysis, and enzymolytic properties varied among the samples. GTA-sponge and GP-sponge possessed high compressive moduli, and EDC-sponge exhibited fast degradation performance. GTA and GP sponge implants exerted strong in vivo rejections, and the former showed poor cell growth. mTG-sponge exhibited the optimal comprehensive performance, with good porosity, compressive modulus, anti-degradation ability, and good biocompatibility. Hence, mTG-sponge can be used as a scaffold material for tissue engineering applications.
The surface functional groups of thermally reduced graphene nanosheets (TRG) prepared by vacuum promoted thermal expansion of graphene oxide are tailored by progressive carbonization. The residual ...carbon ratios after annealing at various temperatures from 250 to 1000°C increase progressively from 44.3 to 84.8%. The oxygen containing functional groups are intensively removed at higher annealing temperature. The thermally stable phenols, ethers, and carbonyls become the major components in 1000°C annealed TRG. Though the starting material G250 owns a high specific capacitance of 170.5F/g, the value decreases to only 47.5F/g when the annealing temperature is increased to 1000°C. The oxygen containing functional groups can enhance the capacitance performance of TRGs by introducing abundant pseudocapacitance active sites through reversible Faradic redox reactions. The correlation between the structural evolution and electrochemical performance of TRGs provides new insight for designing graphene based electrodes with controllable properties for advanced supercapacitors.
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