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There is a growing demand for intensive care units, but there is a relative shortage of medical staff. Intensive care work is heavy and stressful. Optimizing the working conditions and processes of the intensive care unit is of great significance for improving the work efficiency and the level of diagnosis and treatment in the intensive care unit. The intelligent intensive care unit is a new ward management model gradually developed on the basis of modern science and technology such as communication technology, internet of things, artificial intelligence, robots, and big data. Under this model, the potential risks caused by human factors are greatly reduced, and the monitoring and treatment of patients has been significantly improved. This paper reviews the progress in related fields. [ABSTRACT FROM AUTHOR]

Background: The incidence of acute kidney injury (AKI) is high in critically ill patients with rhabdomyolysis. Limited evidence was proved of the association between serum phosphate levels at intensive care unit (ICU) admission and the subsequent risk of AKI. Our study aims to assess if serum phosphate levels at admission were independently associated with AKI risk in these patients.Methods: This study extracted and analyzed data from Medical Information Mart for Intensive Care-Ⅲ (MIMIC-Ⅲ, version1.4). Rhabdomyolysis was defined as a peak creatine kinase (CK) level higher than 1000 U/L. Serum phosphate was measured within the first day into the ICU and was categorized to 4 groups (<2.6, 2.6-3.4, 3.5-4.5, >4.5mg/dl). AKI was defined according to the Kidney Disease Improving Global Outcome (KDIGO) guidelines. Adjusted smoothing spline plots and multivariable logistic regressions were carried out to explode the association between serum phosphate and risk of AKI. Subgroup analyse was applied to verify the consistency of the association.Results: Three hundred and twenty-one patients (68% male) diagnosed as rhabdomyolysis were eligible for this analysis. AKI occurred in 204 (64%) patients of total. Incidence of AKI with admission serum phosphate groups<2.6, 2.6-3.4, 3.5-4.5 and>4.5mg/dl were 53%, 57%, 68% and 76%, respectively. Smoothing spline curve showed that there was a positive curve between the elevated phosphate values and increasing risk of AKI, and there was no threshold saturation effect. In multivariable logistic regression, OR was 1.2 (95%CI 1.0-1.5, P=0.035, P trend=0.041) after adjusting confounders. Subgroup analyses proved the consistency of the relationship in these patients, possibly, except in the strata of potassium.Conclusion: In rhabdomyolysis patients admitted to ICU, serum phosphate levels at admission were independently associated with an increased risk of AKI. As phosphate levels rise, the risk of AKI increased. [ABSTRACT FROM AUTHOR]

The aim of this study is to assess serum human epididymis protein 4 (HE-4) levels as a biomarker for predicting the recurrence of atrial fibrillation (AF) after catheter ablation. This was a prospective observational study that enrolled one hundred eighty-four consecutive nonvalvular AF patients (65 persistent, 119 paroxysmal) who were eligible for their first ablation. Multiple Cox proportional hazards models and Kaplan–Meier curve analyses were used to test the association between serum HE-4 levels and AF recurrence after catheter ablation. During the 12-month follow-up, we observed that 47 patients (25.5%) experienced AF recurrence. Patients were divided into tertiles of HE-4 level (T1: < 50 pmol/L; T2: ≥ 50 pmol/L). The AF recurrence rate of higher serum HE-4 level patients was significantly increased (34.6% vs 13.8%, P < 0.001). Generalized additive models were used to visually assess functional relationships between the serum HE-4 levels and the risk of AF recurrence. When stratified with serum levels as the cut-off value, Kaplan–Meier analysis showed that patients with serum HE-4 levels (> 50 pmol/L) had a significantly increased risk of AF recurrence. In addition, multivariate Cox proportional hazard modelling revealed that HE-4 (≥ 50 pmol/L) (HR 2.65; 95% CI 1.34, 5.27, P = 0.005) was independent predictors of AF recurrence. Serum HE-4 levels in patients with AF are associated with postoperative recurrence of AF, and high HE-4 levels are an independent predictor of AF recurrence after ablation. [ABSTRACT FROM AUTHOR]

Objectives: This meta‐analysis aimed to examine the relationship between automatic processes and behavior as well as their moderators. Methods: There were 126 effect sizes (Fisher's Z) extracted from 55 independent research studies involving 10,432 participants. Meta‐analyses were conducted using Comprehensive Meta‐Analysis Version 3.3. Univariate meta‐regression models were used to analyze underlying moderators. Results: Meta‐analysis after correction found that automatic processes could significantly and positively predict behavior, but the effect size was small (Fisher's Z = 0.057, p < 0.001, 95% CI [0.043, 0.070]). Conclusions: Different components of automatic processes, task reliability, and study design moderated the relationship between automatic processes and behavior. Future research could explore automatic measures at a neurophysiological level or use population‐matched stimuli for specific populations to improve measure validity. In addition, future research should accumulate evidence on how to reduce sedentary behavior. [ABSTRACT FROM AUTHOR]

[Display omitted] • A method for rapid detection of molybdenum ore grade is proposed. • The method is based on visible-infrared spectroscopy and machine learning. • Detection of spectral non-linear behavior by graphical diagnosis and numerical calculation. • Proposed MTSVD-TGJO-ELM algorithm. • MTSVD-TGJO-ELM has the highest accuracy. The rapid determination of ore grade can improve the efficiency of beneficiation. The existing molybdenum ore grade determination methods lag behind the beneficiation work. Therefore, this paper proposes a method based on a combination of Visible-infrared spectroscopy and machine learning to rapidly determine molybdenum ore grade. Firstly, 128 molybdenum ores were collected as spectral test samples to obtain spectral data. Then 13 latent variables were extracted from the 973 spectral features using partial least square. The Durbin-Watson test and the runs test were used to detect the partial residual plots and augmented partial residual plots of LV 1 and LV 2 to determine the non-linear relationship between spectral signal and molybdenum content. Extreme Learning Machine (ELM) was used instead of linear modeling methods to model the grade of molybdenum ores because of the non-linear behavior of the spectral data. In this paper, the Golden Jackal Optimization of adaptive T-distribution was used to optimize the parameters of the ELM to solve the problem of unreasonable parameters. Aiming at solving ill-posed problems by ELM, this paper decomposes the ELM output matrix by using the improved truncated singular value decomposition. Finally, this paper proposes an extreme learning machine method based on a modified truncated singular value decomposition and a Golden Jackal Optimization of adaptive T-distribution (MTSVD-TGJO-ELM). Compared with other classical machine learning algorithms, MTSVD-TGJO-ELM has the highest accuracy. This provides a new method for rapid detection of ore grade in the mining process and facilitates accurate beneficiation of molybdenum ores to improve ore recovery rate. [ABSTRACT FROM AUTHOR]

Ginsenosides, agents extracted from an important herb (ginseng), are expected to provide new therapies for endometrium-related diseases. Based on the molecular types of ginsenosides, we reviewed the main pharmacological effects of ginsenosides against endometrium-related diseases (e.g., endometrial cancers, endometriosis, and endometritis). The mechanism of action of ginsenosides involves inducing apoptosis of endometrium-related cells, promoting autophagy of endometrium-related cells, regulating epithelial-mesenchymal transition (EMT) in endometrium-related cells, and activating the immune system to kill cells associated with endometrial diseases. We hope to provide a theoretical foundation for the treatment of endometrium-related diseases by ginsenosides. [ABSTRACT FROM AUTHOR]

We calculate B ̄ s 0 → ϕ translation form factors V , A 0 , A 1 , A 2 based on QCD sum rule and study the nonleptonic two-body decay of B ̄ s 0 → J / ψ ϕ with the form factors obtained. We calculate the time-integrated branching ratio of B ̄ s 0 → J / ψ ϕ decay. The results for both the total branching ratio and the cases for the final vectors in longitudinal and transverse polarizations are consistent with experimental data. [ABSTRACT FROM AUTHOR]

The performance of bare TiO2 photoanodes in photoelectrochemical devices and other applications is suboptimal due to the narrow light absorption range and poor electron-hole separation. Here, heterostructured films of Ni-doped lead titanate (PbTi1−xNixO3, PTN)-coated titania (TiO2) nanorod arrays were fabricated via a two-step process comprising hydrothermal and sol-gel methods. In the PTN/TiO2 composite films, the PTN component served as a visible light-responsive photosensitizer and the TiO2 nanorod was the electron transport layer. When applied as photoanodes, the PTN/TiO2 films achieved the maximum photoconversion efficiency of ~2.6% and a photocurrent intensity of about 4 times higher than that of the PbTiO3/TiO2 film. These results demonstrate that the ferroelectric material-coated TiO2 heterostructured films have high potential for application in photoelectric and optical devices. [ABSTRACT FROM AUTHOR]

Background and Objectives: The optimal delivery of enteral nutrition in shock patients has an important prognostic clinical value; thus, checklists for standardizing enteral nutrition should be developed. This study examined whether the use of an enteral feeding checklist can improve enteral nutrition in shock patients.Methods and Study Design: A retrospective cohort study was conducted. A multidisciplinary working group developed an enteral feeding checklist. Information on patients' demographics, checklist items, and clinical outcomes was collected.Results: In total, 148 patients were included. The checklist was used for 35 patients but not for the remaining 113 patients. Patients in the checklist group received enteral nutrition earlier (2.6 vs 4.6 days, p=0.017) and had a lower mechanical ventilation rate (62.9% vs 85.0%, p=0.004). The checklist group had shorter intensive care unit stay (mean 17.3 vs 25.7 days, p=0.043). No significant differences were observed in 28- and 90- day mortality, mechanical ventilation duration, and intolerance to enteral nutrition.Conclusions: The use of an enteral feeding checklist in shock patients was associated with earlier enteral nutrition delivery and decreased intensive care unit stay. [ABSTRACT FROM AUTHOR]

This study focuses on the stability property of a class of distributed delay systems with constant coefficients. More precisely, the authors will discuss deeper the stability analysis with respect to the delay parameter. The authors' approach will allow to give new insights in solving the so‐called complete stability problem. There are three technical issues need to be studied: First, the detection of the critical zero roots (CZRs); second, the analysis of the asymptotic behaviour of such CZRs; third, the asymptotic behaviour analysis of the critical imaginary roots (CIRs) with respect to the infinitely many critical delays. They extended their recently‐established frequency‐sweeping approach, with which these technical issues can be effectively solved. Based on these results, a procedure was proposed, with which the complete stability analysis of such systems was accomplished systematically. Moreover, the procedure represents a unified approach: Most of the steps required by the complete stability problem may be fulfilled through observing the frequency‐sweeping curves. Finally, some examples illustrate the effectiveness and advantages of the approach. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to compare the effectiveness of different fluids on critically ill patients who need fluid resuscitation through a systematic review and network meta-analysis (NMA).Data Sources: Electronic databases were searched up to March 2018 for randomized controlled trials comparing the effectiveness of different fluids in critically ill patients. The primary outcome was mortality, and the secondary outcomes were the incident of acute kidney injury (AKI) and risk of receiving renal replacement therapy (RRT). A Bayesian NMA was conducted, and the quality of evidence contributing to each network estimate was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) Working Group criteria.Results: We deemed 49 trials eligible, including 40,910 participants. The quality of evidence was rated as moderate in most comparisons. There was no significant difference among resuscitation fluids in mortality. NMA at the 9-node level showed the most effective fluid was balanced crystalloid (BC) (80.79%, the ranking of resuscitation fluid based on cumulative probability plots and surface under the cumulative ranking curves [SUCRAs]). NMA at the 10-node level showed that the most effective fluid was Plasma-Lyte (77.52%). Results of sensitivity analyses in mortality did not reveal any significant changes in the findings for primary outcomes. High-molecular-weight hetastarch (H-HES) was associated with an increased incidence of AKI when compared with gelatin (odds ratio [OR], 0.43; 95% credibility interval [CrI], 0.19-0.94), low-molecular-weight hetastarch (L-HES; OR, 0.50; 95% CrI, 0.30-0.87), BC (OR, 0.55; 95% CrI, 0.34-0.88), and normal saline (OR, 0.56; 95% CrI, 0.34-0.93). Meanwhile, H-HES was also associated with an increased risk of receiving RRT when compared with BC (OR, 0.51; 95% CrI, 0.27-0.93) and normal saline (OR, 0.52; 95% CrI, 0.24-0.96).Conclusion: BCs, especially the Plasma-Lyte, are presumably the best choice for most critically ill patients who need fluid resuscitation. Meanwhile, the use of H-HES was associated with an increased incidence of AKI and risk of receiving RRT.Registration: PROSPERO (CRD42017072728). [ABSTRACT FROM AUTHOR]

This document is an editorial for a special issue of the journal Sensors titled "Sensing-Based Biomedical Communication and Intelligent Identification for Healthcare." The editorial highlights the importance of integrating sensor technology in healthcare for disease diagnosis and treatment. It discusses the development of various types of sensors and data processing algorithms, as well as advancements in artificial intelligence (AI) and sensing technology. The special issue includes original research articles and reviews that explore the latest developments and challenges in sensor-based information extraction for disease diagnosis and health monitoring. The articles cover topics such as innovative sensors for healthcare applications, processing algorithms for wearable sensors, analysis of public datasets, and the application of machine learning techniques for disease monitoring and management. The editorial concludes by stating that the special issue provides readers with a comprehensive view of the latest prospects of sensors for healthcare applications. [Extracted from the article]

Glass transition, commonly manifested upon cooling a liquid, is continuous and cooling rate dependent. For decades, the thermodynamic basis in liquid–glass transition has been at the center of debate. Here, long-time isothermal annealing was conducted via molecular dynamics simulations for metallic glasses to explore the connection of physical aging in supercooled liquid and glassy states. An anomalous two-step aging is observed in various metallic glasses, exhibiting features of supercooled liquid dynamics in the first step and glassy dynamics in the second step, respectively. Furthermore, the transition potential energy is independent of initial states, proving that it is intrinsic for a metallic glass at a given temperature. We propose that the observed dynamic transition from supercooled liquid dynamics to glassy dynamics could be glass transition manifested isothermally. On this basis, glass transition is no longer cooling rate dependent, but is shown as a clear phase boundary in the temperature-energy phase diagram. Hence, a modified out-of-equilibrium phase diagram is proposed, providing new insights into the nature of glass transition. [ABSTRACT FROM AUTHOR]

Background: A long-axis in-plane (LA-IP) approach and a short-axis out-of-plane (SA-OOP) approach are the two main approaches used in ultrasound (US)-guided vascular catheterization. However, the efficacy and safety of these approaches remain controversial. Therefore, we performed this meta-analysis to compare the two techniques in vascular catheterization. Materials and methods: Relevant studies were searched in PubMed, Embase, and the Cochrane Library databases from database inception until August 2017. Randomized controlled trials comparing a long-axis approach with a short-axis approach for US-guided vascular cannulation were selected. The RevMan software was used to analyze the results, and trial sequential analysis (TSA) was further applied to determine whether the currently available evidence was sufficient and conclusive. Results: Eleven studies met the inclusion criteria. Overall, 1,210 patients were included. The total success rate was similar between the SA-OOP and LA-IP approaches for US-guided vascular catheterization (risk ratio [RR], 1.01; 95% CI, 0.99-1.04; P=0.35; I2=48%). In the radial artery (RA; RR, 1.00; 95% CI, 0.96-1.05; P=0.88; I2=49%) and internal jugular vein (IJV; RR, 1.00; 95% CI, 0.98-1.02; P=0.99; I2=0%) subgroups, the total success rate was also similar and was confirmed by the TSA. For populations with subclavian vein (SCV) and axillary vein catheterization, the SA-OOP approach showed a benefit for first-attempt success rate. No significant differences in first-attempt success rate, cannulation times, or complications were found between the two approaches. Conclusion: Despite a similar total success rate between the SA-OOP approach and the LA-IP approach when used for RA and IJV catheterization (as confirmed by TSA), further robust well-designed trials are warranted to evaluate other outcomes. There is insufficient evidence to definitively state that the SA-OOP approach was superior to the LA-IP approach when used for SCV and axillary vein catheterization. High-quality trials are needed to confirm or refute this finding. [ABSTRACT FROM AUTHOR]

A relationship between triboelectric charge and contact force for two triboelectric layers is presented, by combining the theories of insulator contact charging and contact mechanics. Experimental verification has been successfully performed using contact-mode triboelectric nanogenerators (TENGs) in two cases: (a) under varying contact forces while keeping the surface roughness profile constant, and (b) under varying surface roughness profiles while keeping the contact force constant. The theory presented here can serve as an important guide in the design of triboelectric systems, particularly of a contact-mode TENG structure for specific applications and self-powered systems. [ABSTRACT FROM AUTHOR]

Hetrombopag olamine (hetrombopag) is a novel small-molecule, orally bioavailable, non-peptide thrombopoietin ( TPO) receptor agonist that is being developed as the treatment for thrombocytopenia. Two randomized, placebo-controlled phase I studies were conducted in 72 healthy individuals to assess the safety, tolerability, pharmacokinetics and pharmacodynamics of hetrombopag. Hetrombopag was orally administered with a single dose in five dose cohorts (5 mg, 10 mg, 20 mg, 30 mg or 40 mg) in the first study, and given once daily for 10 days in three dose cohorts (2.5 mg, 5.0 mg or 7.5 mg) in the second study, respectively. Hetrombopag was well tolerated, and the majority of adverse events associated with medicine were platelet elevations significantly above the normal range in healthy individuals. The single dose-escalation study revealed a Tmax of approximate 8 hr, and a t1/2 of 11.9 hr to 40.1 hr in a dose-prolonged manner. A dose-proportional increase in maximum concentration ( Cmax) of hetrombopag was observed, with area under the curve ( AUC) increasing in a greater than dose-proportional manner. The plasma concentration of hetrombopag reached the steady-state after 7 days. The steady-state AUC0-24 hr and Cmax were dose-proportionally elevated from the 5.0 mg to 7.5 mg dose level. The potent pharmacological effect of the hetrombopag-induced platelet elevation was observed in a time- and dose-dependent manner. Furthermore, the thrombopoietic response was significantly ( p < 0.0001) correlated to the plasma exposure level of hetrombopag in single and multiple administration studies. Taken together, results of this study support further clinical development of hetrombopag in patients with thrombocytopenia. [ABSTRACT FROM AUTHOR]

A stochastic predator-prey system with time-dependent delays is considered. Firstly, we show the existence of a global positive solution and stochastically ultimate boundedness. Secondly, the critical value between weak persistence and extinction of the prey is obtained and we also give the asymptotic pathwise estimation. Finally, we simulate the model to illustrate our results. [ABSTRACT FROM AUTHOR]

Structural connections among the hubs of the revised Papez circuit remain to be elucidated in the human brain. As the original Papez circuit failed to explain functional imaging findings, a more detailed investigation is needed to delineate connections among the circuit’s key hubs. Here we acquired diffusion spectrum imaging (DSI) from eight normal subjects and used data from the Human Connectome Project (HCP) to elucidate connections among hubs in the retrosplenial gyrus, hippocampus, mammillary bodies, and anterior thalamic nuclei. Our results show that the ventral hippocampal commissure (VHC) was visualized in all eight individual DSI datasets, as well as in the DSI and HCP group datasets, but a strictly defined VHC was only visualized in one individual dataset. Thalamic fibers were observed to connect with both the posterior cingulate cortex (PCC) and retrosplenial cortex (RSC). The RSC was mainly responsible for direct hippocampal connections, while the PCC was not. This indicates that the RSC and PCC represent separate functional hubs in humans, as also shown by previous primate axonal tracing studies and functional magnetic resonance imaging observations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Design, synthesis and antitumor evaluation of biotin-PEG4‑diarylidenyl piperidone prodrugs. • In vitro and In vivo antitumor activity screening for prodrugs 3a and 3b. • 3a and 3b released their original drugs DAP-F and DAP-NO 2 in nude mice. • DAP-F , DAP-NO 2 , 3a and 3b targeted STAT3 inhibition. • 3a and 3b interacted with SH2-binding domain, while DAP-F and DAP-NO 2 interacted with DNA-binding domain. Two biotin-polyethylene glycol (PEG)4‑diarylidenyl piperidone (DAP) prodrugs, compounds 3a and 3b , were designed as antineoplastic agents and synthesized by coupling biotin to bifluoro- and binitro-substituted DAP derivatives (DAP-F and DAP-NO 2) through a PEG4 linker, respectively. The results of the MTT (3-(4, 5)-dimethylthiahiazo (-z-y1)-3, 5-di- phenytetrazoliumromide) assay and a SW480 xenograft model identified compounds 3a and 3b as candidate antitumor agents with good efficacy, limited toxicity, and low resistance, as compared to the original drugs (DAP-F and DAP-NO 2), cisplatin, and doxorubicin (dox). The results of a preliminary pharmacokinetic study showed that compounds 3a and 3b slowly released their original drug DAP-F and DAP-NO 2 within 12 h after intraperitoneal injection, respectively. Western blot analysis and computer docking simulations indicated that DAP-F , DAP-NO 2 , and compounds 3a and 3b were indeed inhibitors of signal transducer and activator of transcription 3 (STAT3) and the antitumor effects of compounds 3a and 3b were exerted by sequentially interacting with the SH2-binding domain followed by the DNA-binding domain after releasing the original drugs DAP-F and DAP-NO 2 , respectively. These results suggest that the targeted prodrug model led to good antitumor efficacy with reduced toxicity, while a dual STAT3-binding model may promote antitumor efficacy and resistance. [ABSTRACT FROM AUTHOR]

The need to recharge and eventually replace batteries is increasingly significant for operating a variety of wearable electronic devices. Rapid advances in low power design have stimulated the requirements for portable and sustainable power sources, thus opening the possibility of using human biomechanical energy as a promising alternative power source. Respiration is a unique form of spontaneous and stable source of human biomechanical energy that is currently untapped, and has the potential to be converted to a sustainable power source for low power wearable electronic devices and integrated body sensor networks. However, effectively harvesting respiration energy characterized by low frequency and low force is currently a technological challenge, and cannot be well‐achieved by classical energy harvesting methods. In this work, a triboelectric nanogenerator based on contact–separation mode is demonstrated as a small and light‐weight wearable respiratory energy harvester (wREH). The wREH can also be utilized as a self‐powered respiratory motion sensor capable of tracking rate and depth of respiration. A simple and cost‐effective poly lactic‐co‐glycolic acid patterning technique is utilized to create microdome‐patterned polydimethylsiloxane for increasing the effective contact area of the triboelectric surfaces, thus enhancing power output while achieving higher durability than existing nanosurface structures. [ABSTRACT FROM AUTHOR]

Two discriminant methods, partial least squares-discriminant analysis (PLS-DA) and Fisher's discriminant analysis (FDA), were combined with Fourier transform infrared imaging (FTIRI) to differentiate healthy and osteoarthritic articular cartilage in a canine model. Osteoarthritic cartilage had been developed for up to two years after the anterior cruciate ligament (ACL) transection in one knee. Cartilage specimens were sectioned into 10 m thickness for FTIRI. A PLS-DA model was developed after spectral pre-processing. All IR spectra extracted from FTIR images were calculated by PLS-DA with the discriminant accuracy of 90%. Prior to FDA, principal component analysis (PCA) was performed to decompose the IR spectral matrix into informative principal component matrices. Based on the different discriminant mechanism, the discriminant accuracy (96%) of PCA-FDA with high convenience was higher than that of PLS-DA. No healthy cartilage sample was mis-assigned by these two methods. The above mentioned suggested that both integrated technologies of FTIRI-PLS-DA and, especially, FTIRI-PCA-FDA could become a promising tool for the discrimination of healthy and osteoarthritic cartilage specimen as well as the diagnosis of cartilage lesion at microscopic level. The results of the study would be helpful for better understanding the pathology of osteoarthritics. [ABSTRACT FROM AUTHOR]

Herein, we report a novel quinoline derivative-based two-photon fluorescent probe 6-(dimethylamino)quinoline-2-benzothiazoline ( HQ), which is capable of tracking superoxide anion in organisms with specific “turn-on” fluorescence response based on extension of π-conjugations and moderate ICT process. The probe exhibited favorable photophysical properties, a broad linear range and high photostability. It can specifically detect superoxide anion with a significant fluorescence enhancement and great linearity from 0 to 500 μM in PBS buffer. Furthermore, HQ shows low cytotoxicity and excellent photostability toward living cells and organisms, which was able to monitor endogenous superoxide anion fluxes in living cells and in vivo . For the first time, endogenous superoxide anion in lung inflammation was visualized successfully by using HQ through two-photon microscopy, and the probe HQ shows great potential for fast in-situ detecting of inflammatory response in live organisms. [ABSTRACT FROM AUTHOR]

In this work, we study the radiative leptonic decays of B − and D − mesons using factorization approach. Factorization is proved to be valid explicitly at 1-loop level at any order of O ( Λ QCD / m Q ) . We consider the contribution in the soft photon region that E γ ∼ Λ QCD 2 / m Q . The numerical results show that, the soft photon region is very important for both the B and D mesons. The branching ratios of B → γ e ν e is 5.21 × 10 − 6 , which is about 3 times of the result obtained by only considering the hard photon region E γ ∼ m Q . And for the case of D → γ e ν e , the result of the branching ratio is 1.92 × 10 − 5 . [ABSTRACT FROM AUTHOR]

Ambient energy harvesting has gained considerable interest as a potential power source for portable electronic devices and wireless sensor networks since the last decade. Triboelectric generators based on contact electrification and electrostatic induction have recently emerged as a promising mechanical energy harvesting technique. However, due to the complex nature of contact electrification, the underlying mechanism of charge transfer between two contacting surfaces when at least one of them is insulating, remains an unresolved problem in physics. Determining and controlling surface charge density is therefore a significant problem, making prediction of the output voltage of a triboelectric generator a challenge. In addition, structural parameters such as area, gap, and dielectric thickness, which affect the output voltage of the generator, have previously been investigated individually but their interaction effects have not been taken into account. Presented here, for the first time, is a method to design finite element simulations of triboelectric generators using experimentally derived surface charge density as a boundary condition in order to investigate the overall effect of the structural parameters on generator's output voltage. Two metamodels have been established as a result of a 2 3 full factorial design and a central composite design. The models have been experimentally verified, and have shown to predict the output voltage within one order of magnitude. [ABSTRACT FROM AUTHOR]

Freshwater polyculture systems should efficiently utilise natural food resources and pond habitats with the consequent effects of reducing costs and increasing productivity. However, understanding of the primary carbon sources and food web within polyculture ponds, and especially macrophyte-dominated ponds, remains limited., Stable-isotope analysis was used to identify the main carbon sources and describe the trophic patterns of freshwater fauna in a polyculture pond around Lake Gucheng, China. An isotope mixing model (SIAR) was also used to estimate the relative contribution of four basal sources (suspended particulate organic matter [SPOM], sedimentary organic matter [SOM], macrophytes and epiphytes) to invertebrates and different fish trophic groups., Basal resources showed distinct δ13C values, ranging from −24.3 to −20.5‰, which allowed for a powerful discrimination of carbon sources. Consumers were also well separated in δ13C (−24.0 to −20.0‰ for invertebrates and −24.4 to −18.9‰ for fish), suggesting considerable differences in ultimate sources of carbon. Results from the SIAR model indicated that epiphytes were the most important carbon sources for crustaceans, herbivorous fish, omnivorous fish and piscivorous fish, while SPOM made the highest contribution to zooplankton, chironomids, molluscs, annelids, planktivorous fish and benthivorous fish., Mean δ15N values, combined with calculated food source contributions, were used to elucidate the food-web structure of this polyculture pond, which suggested that carbon fixed by primary producers could be transported up the food chain to piscivorous fish through four main trophic pathways: one based mainly on SPOM, one on both SPOM and SOM, one on SPOM, SOM, macrophytes and epiphytes, and one based on both macrophytes and epiphytes., Our results emphasised the trophic importance of epiphytes on submerged macrophytes, a key component in the polyculture ponds, for the main culture species: Chinese mitten crab ( Eriocheir sinensis: Varunidae), freshwater shrimp ( Macrobrachium nipponense: Palaemonidae), and high-value piscivorous fish. This study also revealed the high level of complexity of polyculture pond food webs, and suggests that a diversity of major trophic pathways may be a characteristic of macrophyte-dominated aquatic ecosystems. [ABSTRACT FROM AUTHOR]

In this paper, based on the analysis of lab experimental results of 20 core samples, which were drilled from tight sandstone reservoirs of Sichuan basin, and simultaneously applied for mercury injection capillary pressure (MICP) and nuclear magnetic resonance (NMR) measurements, the relationships of piecewise power function between NMR transverse relaxation T 2 time and pore-throat radius R c are established. A novel classified piecewise power function (CPPF) method, which is used to transform NMR reverse cumulative curve as pseudo capillary pressure ( P c ) curve is proposed, and the corresponding model is established based on formation classification. By using this model, formation pseudo P c curves can be consecutively synthesized in the intervals with which field NMR logs were acquired. The pore throat radius distribution, and pore structure evaluation parameters, such as average pore throat radius (Rm), threshold pressure (Pd), maximum pore throat radius (Rmax) and so on, can also be precisely extracted. Several tight sandstone reservoirs are processed by using this method, and the predicted results are compared with core derived results. Good consistency between the evaluated results with core derived results illustrates the dependability of the proposed method. [ABSTRACT FROM AUTHOR]

Purpose: This study was to test the hypothesis that intramedullary (IM) nailing fixation of midshaft clavicle fractures could result in better clinical outcomes and lower complications rates than plating fixation.Methods: PubMed, Embase, and the Cochrane Library database were used to search all English language published randomized controlled trials (RCTs) of midshaft clavicle fractures using plating versus IM nailing. The characteristics of the study participants were collected. Outcomes of postoperative shoulder functional measurements, operative data and complications rates were meta-analyzed.Results: Eight hundred and ninety-five patients in ten RCTs and three quasi-RCTs were involved in the meta-analysis. The results of meta-analysis of these studies showed that the functional outcome evaluated by the Constant Shoulder and Disabilities of the Arm, Shoulder and Hand (DASH) scores after accepting IM nailing was significantly better than that of plating fixation at one year post-operatively (P < 0.01), with the heterogeneity of 43% and 91%, respectively. Sensitivity analyses of the pooled results of Constant and DASH scores displayed that the functional advantage of IM nailing fixation comes from the subgroup of locked IM nailing. Further, regarding the operative statistics, operative time, blood loss and wound length were significantly less in the IM nailing group than the plating group (P < 0.001). The rates of infection, major complications and complications-related revision surgery were significantly higher in the plating group than the IM nailing group; however, there were no significantly statistical differences in other complications, e.g., nonunion, refracture after hardware removal, implant failure, symptomatic hardware, etc. (P > 0.05).Conclusion: The observations in this review suggested that IM nailing, especially locked IM nailing, could provide better shoulder functional outcome at one-year follow-up. Moreover, IM nailing fixation could effectively reduce operative time, blood loss, rates of infection, major complications, and revision surgery than plating. Further high-quality clinical trials with large samples and consistent designs are still needed to verify the long-term functional advantage of locked and unlocked IM nailing for midshaft clavicle fractures.Level Of Evidence: Level II. [ABSTRACT FROM AUTHOR]

A generalized mathematical model, which describes the process of lithium extraction/insertion in active material particles of insertion cathodes, is developed from linear non-equilibrium thermodynamics and the principle of electroneutrality. The model reveals theoretical relations between the intrinsic and apparent transport parameters of lithium-ions and electrons. Calculation formulas for apparent lithium-ion diffusion coefficient D 1 ⁎ are deduced from the model. A simple trial calculation is introduced to evaluate the cross-phenomenological coefficient of the Onsager reciprocal relationship. By means of referenced intrinsic diffusion coefficients, calculated by ab initio methods, calculations of D 1 ⁎ upon charge/discharge for the lithium iron phosphate cathode material (FePO 4 /LiFePO 4 ) are presented. The calculated values of D 1 ⁎ are within those previously measured experimentally. In the range of lithium ion contents 0.02 ≤ x ≤ 1.0, the values of D 1 ⁎ during charge/discharge vary in the range 10 − 12 –10 − 14 cm 2 s − 1 and decrease with increasing x . The mean value of D 1 ⁎ is about 10 − 13 cm 2 s − 1 , which is five to six orders of magnitude lower than the intrinsic diffusion coefficients. The calculation results indicate that lithium ion diffusion in the active material particles is coupled with electron conduction, and the co-diffusion of lithium ions and electrons is limited by the electron conduction due to the low intrinsic conductivity of FePO 4 /LiFePO 4 . [ABSTRACT FROM AUTHOR]

In this work, we study the radiative leptonic decays of and mesons in the Standard Model (SM) and two-Higgs-doublet-model (2HDM) Type II. The results are obtained using the factorization procedure, and the contribution of the order is included. The numerical results are calculated using the wave function obtained in relativistic potential model. As a result, the decay mode is found to be sensitive to the effect of the charged Higgs boson. Using the constraint on the free parameters of 2HDM given in previous works, we find the contribution of the charged Higgs boson in the decay mode can be as large as about 13%. [ABSTRACT FROM AUTHOR]

Rare-earth containing phosphors have been widely applied in lighting and display fields in the past century. Lower cost rareearth free phosphors with high performance are highly desired driven by the exhaustion of rare earth resources and the requirement of cheaper production. Herein, Cu+ ions doped tetracalcium phosphate (TTCP) yellow emitting phosphors with quantum yield of 21% are exploited. Particularly, ultra-broad band emission with a full width at half maximum (FWHM) about 200 nm throughout almost entire visible light region is observed for TTCP: Cu+ phosphors, evidencing its promising application in high color rendering index (CRI) lighting source. White light emission with CRI value about 94.3 is generated by combining this TTCP: Cu+ phosphor with commercial BaMgAl10O17: Eu2+ blue phosphor, exhibiting superiority over the traditional trichromatic phosphors. Therefore, we predict great potential application for this cheaper rare-earth free TTCP: Cu+ phosphor in high CRI lighting sources. [ABSTRACT FROM AUTHOR]

Electron beam welding (EBW) is manufacturing parts with heavy thickness, but the evaluation of the properties is incomplete. We employed oscillation EBW to weld Ti6.5Al2Zr1Mo1V alloy with 60 mm thickness, and observed weld microstructures, and studied the properties of high cycle fatigue. Compared with base metal at constant peak stress, fatigue strength of the joints was equivalent to that of base metals, and fatigue life was different from that of base metal. The fatigue cracks of base metal specimens originated from the surfaces, and the cracks of the joints were from the surfaces in base metal or interior welding porosities. With the decrease of the distance from welding porosity to the surface of the specimens, fatigue life of the joints gradually lowered. Fatigue life also reduced with the increase of the diameter of welding porosities, the influences of which were inferior to the location. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance In traditional Chinese medicine (TCM), Abelmoschus manihot (L.) medic (AM) is a natural medicinal plant used for the treatment of inflammatory diseases. Recently, Huangkui capsule (HKC), a Chinese patent medicine extracted from AM, has been widely applied to the clinical therapy of renal fibrosis in patients with early diabetic nephropathy (DN). However, the therapeutic mechanisms involved in vivo remain ambiguous. The goal of this study is to expound the mechanism in vivo of HKC in order to deepen the understanding of its clinical effects, by using the approaches of contrasting the dose-effects of HKC on oxidative stress (OS) in the kidney compared to α-lipoic acid (LA), and then demonstrating whether and how anti-oxidative properties of HKC or LA might be beneficial for the treatment of renal fibrosis in vivo. Materials and methods Thirty-three rats were divided into 5 groups, a Sham group, a Vehicle group, a L-HKC group, a H-HKC group and a LA group. The different doses of HKC, LA and distilled water were daily administrated for 8 weeks after the induction of DN by the unilateral nephrectomy combined with streptozotocin (STZ) intraperitoneal injections. Rat's general status, biochemical parameters, renal histological changes and OS indicators, as well as the key protein expressions in p38 mitogen-activated protein kinase (p38MAPK)/serine-threonine kinase (Akt) signaling pathways and downstream cytokines including transforming growth factor (TGF)-β1 and tumor necrosis factor (TNF)-α were examined, respectively. Results HKC and LA ameliorated body weight, kidney weight, urinary albumin and renal function including blood urea nitrogen and serum uric acid, attenuated renal fibrosis including the cell numbers and extracellular matrix rate in glomerulus, and controlled OS indicators including malondialdehyde, total superoxide dismutase, 8-hydroxy-2′-deoxyguanosine and nicotinamide adenine dinucleotide phosphate oxidase 4, but did not lower blood glucose in DN model rats. Among them, the anti-renal fibrosis effect of H-HKC was better than that of LA. In addition, HKC simultaneously down-regulated the protein expressions of phosphorylated p38MAPK, phosphorylated Akt (p-Akt), TGF-β1 and TNF-α in the kidney of DN model rats, unlike HKC, LA only down-regulated p-Akt and TNF-α protein expressions. Conclusion We have demonstrated that HKC, similar to LA, is renoprotective via attenuating OS and renal fibrosis in the DN rat model. The potential mechanisms by which HKC and LA exert their therapeutic effects in vivo are respectively through down-regulating the activation of p38MAPK and/or Akt pathways as well as the expressions of TGF-β1 and/or TNF-α in the kidney. Our findings thus provide the useful information about a clinical combination of HKC and LA in early DN patients. [ABSTRACT FROM AUTHOR]

Sr 2 RuO 4 , featuring a layered perovskite crystalline and quasi-two-dimensional electronic structure, was first synthesized in 1959. Unconventional, p -wave pairing was predicted for Sr 2 RuO 4 by Rice and Sigrist and Baskaran shortly after superconductivity in this material was discovered in 1994. Experimental evidence for unconventional superconductivity in Sr 2 RuO 4 has been accumulating in the past two decades and reviewed previously. In this article, we will first discuss constraints on the pairing symmetry of superconductivity in Sr 2 RuO 4 and summarize experimental evidence supporting the unconventional pairing symmetry in this material. We will then present several aspects of the experimental determination of the unconventional superconductivity in Sr 2 RuO 4 in some detail. In particular, we will discuss the phase-sensitive measurements that have played an important role in the determination of the pairing symmetry in Sr 2 RuO 4 . The responses of superconductivity to the mechanical perturbations and their implications on the mechanism of superconductivity will be discussed. A brief survey of various non-bulk Sr 2 RuO 4 will also be included to illustrate the many unusual features resulted from the unconventional nature of superconductivity in this material system. Finally, we will discuss some outstanding unresolved issues on Sr 2 RuO 4 and provide an outlook of the future work on Sr 2 RuO 4 . [ABSTRACT FROM AUTHOR]

To implement optimization and control on gold cyanidation leaching process (GCLP), it is an important prerequisite to establish an accurate process model. In this paper, a hybrid model in serial structure was proposed, where a first-principle model based on mass conservation equations was presented to describe the basic process behavior and its unknown kinetic reaction rates were predicted using BP ANN models without any structures considered. The proposed serial hybrid model had been applied to the prediction of gold recovery of the GCLP in a gold treatment plant. The results indicate that the proposed serial hybrid model has better prediction performance and generalization ability than the pure mechanistic model. To further reduce the effect of prediction error (plant-model mismatch) on real time optimization (RTO), modifier adaptation approach had been investigated and implemented to the GCLP. The result shows that when model mismatches with the actual plant or larger process disturbance occurs, significant reduction of production cost can be actualized iteratively by implementing the proposed adaptive RTO strategy. [ABSTRACT FROM AUTHOR]

Tricolor emission CaSiO:Ln (Ln = Ce, Eu, Sm) phosphors were synthesized by the conventional solid-state reaction method, and their photoluminescence properties were investigated. Ce-, Eu-, or Sm-doped CaSiO phosphors showed typical blue, green, or red luminescence in the CIE1931 chromaticity diagram, respectively. In addition, the luminescence efficiency of the tricolor emission CaSiO:Ln (Ln = Ce, Eu, Sm) phosphors was evaluated. A series of white light-emitting diode (LED) prototypes were fabricated by combining near-UV LED chip and the as-prepared tricolor emission phosphors with various ratios in weight. White LED prototypes with tunable correlated color temperature and color-rendering index values were realized by controlling the amount of phosphors. The presented results indicated the potential application of CaSiO:Ln (Ln = Ce, Eu, Sm) phosphors in near-UV white LED. [ABSTRACT FROM AUTHOR]

Abstract: With the development of welding technology, electron beam welding (EBW) is manufacturing the aero parts with heavy thickness. To improve welding quality and mechanical property, we employed EBW with beam oscillation on Ti6.5Al2Zr1Mo1V alloy with 60mm thickness, and observed the weld microstructures after X-ray NDT, and conducted the tensile and impact tests under different temperatures. The results showed the crystals of the welds were fringe, and the microstructures of the welds were acicular α′ martensite. The acicular and isometric crystals existed in HAZ, which were α′ martensite mixed with α+β structure. With the increase of the temperatures, tensile properties of the top and bottom joints gradually lowered, and the strengths were almost equal to base metal, and the percentage elongations after fracture were lower than those of base metals. The strength overmatching of the joints resulted in the inhomogeneous elastic–plastic deformations, and tensile specimens of the joints ruptured in base metal. The impact toughnesses of top welds were equal to the bottoms under different temperatures, which were lower than those of base metals. Electron beam oscillation improved the uniformity of the microstructures, which contributed to the homogeneity of mechanical properties from the top to bottom joints. [Copyright &y& Elsevier]

Background: Small bowel adenocarcinoma (SBA) is a rare occurrence and few studies have addressed it adequately, especially in China. Methods: Clinicopathological features, survival and prognostic analysis were retrospectively done in SBA patients admitted between 2001 and 2011 in the People's Liberation Army General Hospital. Results: The study included 68 men and 51 women with a median age of 56.5 year. Tumors mainly occurred in duodenum (93.3%). Abdominal pain was the most frequent symptom (36.8%). Patients (30.3%) who received postoperative adjuvant chemotherapy had an increased, but not significant, median overall survival (MOS) rate compared to those who did not receive chemotherapy (37 vs 35 months, p = .324). One year disease free survival rate was higher in patients receiving postoperative chemotherapy (83.3% vs 71.1%). Patients survived longer in the curative surgery group (median survival time of 49.0 months) than those in the palliative group (7.0 months) ( p < .001). Node-negative patients survived longer than node-positive patients (median OS: 49.0 vs 21.0 months, p = .004). Depth (95% CI: 1.013-1.517, p = .037), node involvement (95% CI: 1.234-3.890, p = .007), palliative surgery (95% CI, 2.998-10.555, p = .0005), and the site of tumor (95% CI: 0.052-0.970, p = .045) were independent predictors of OS in a multivariate analysis. Conclusions: SBA is rare and there is lack of obvious clinical manifestations. Depth, node involvement, palliative surgery, and the site of tumor are associated with a poor prognosis. Our analysis highlights the need for further studies to find out the exact role of postoperative adjuvant chemotherapy in these patients. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we used oxides (Y2O3, CeO2 and Al2O3) as the raw materials to fabricate YAG:Ce3+ phosphors by a molten salt synthesis (MSS) method. The formation of YAG phase strongly depends on the alumina source and firing temperature. Microstructure characterization indicates that “dissolution-precipitation” mechanism dominates the formation process of YAG in the alkali chlorides melt. Thus, highly active nano-Al2O3 starting powders promote their solution in the melt and guarantee a solute stoichiometric of YAG phase rather than other Y–Al–O compounds. The as-prepared YAG:Ce3+ phosphors show typical yellow emission peaked at 535nm under excitation of 460nm blue light, suggesting that MSS could be a promising method for the preparation of phosphor powders even though oxide raw materials are used. [Copyright &y& Elsevier]

Abstract: For many instances in phosphor materials, mixed valence Eu co-existing phenomenon has been widely reported. It is then of great importance and necessity to identify the charge state and to quantify the content of varied valence Eu ions, because the luminescent properties of phosphors are closely dependent on the valence state of Eu ions and its content. Photoluminescence (PL) spectrum on the emission profile and electron energy loss spectrum (EELS) about the M-edges carry useful information on the valence state of Eu ions. In this work, PL and EELS were employed to identify the charge state of Eu ions in LaAlO3 phosphor, basing on the different emission profile of PL and M5/M4 ratio of EELS signals for varied valence Eu ions. And the relative content ratio of Eu2+/Eu3+ for these incorporated Eu ions in LaAlO3 host was quantified by the PL and EELS. [Copyright &y& Elsevier]

Abstract: Electron beam welding (EBW) with multi-beam is a novel method to decrease weld cracks, which is suitable for welding the parts in aero industries. We studied EBW with multi-beam on high temperature titanium alloy, which was refers to simultaneous EBW with electron beam (EB) preheating or post-heating. We proposed the ratio of the power for welding and preheating or post-heating, and modeled temperature fields and temperature histories by ABAQUS software. The results showed the temperature of EB post-heating was higher than that of EB preheating, and EB preheating and post-heating respectively lowered the temperature gradient of welding heating and welding cooling, which improved the uniformity of the temperature of EBW. The weld morphologies were consistent with those of the modeling, which verified the feasibility and effectiveness of the temperature fields modeled. The microstructures of the welds with post-heating were coarser than those with preheating. The microhardnesses of the welds with preheating and post-heating were more homogeneous. The influences of EB preheating and EB post-heating on EBW were discussed. [Copyright &y& Elsevier]

Highlights: [•] Bimodal emission is originated from β-SiAlON grains with z ≥2. [•] Coexistence of two kinds of emission centers in the β-SiAlON phase is definite. [•] Fluorescence microscopy shows influence of the z value on emission of β-SiAlON. [ABSTRACT FROM AUTHOR]

Highlights: [•] White light was generated in self-activated Ba2TiSi2O8 by doping Ln3+ (Ln=Sm or Eu). [•] Luminescence mechanism and the energy transfer between Ti4+–O2− CT and Ln3+ were investigated. [•] White light with tunable CCT and CRI were demonstrated by varying the content of Eu3+ dopants. [ABSTRACT FROM AUTHOR]

Abstract: Tunable white light of Eu2+ doped SiAlON crystal/glass composite phosphor with blue-yellow dual-emissions was demonstrated by variation of excitation wavelength in this work. The excitation properties of blue emission originated from the transition of Eu2+ ions in the Si–Al–B–O–N glass matrix and that of yellow emission originated from the transition of Eu2+ ions in the SiAlON lattice were investigated, respectively. By varying the excitation wavelength in the range of 330–380nm, white emission was tuned from cool white to warm white for this SiAlON crystal/glass composite phosphor owing to the various excitation properties of these two emission bands. Presented results indicate that this tunable SiAlON crystal/glass composite white-light phosphor might be applied in white LED, combining with UV chips with different emitting wavelengths in the range of 330–380nm. [Copyright &y& Elsevier]

Abstract: Concentration quenching processes and the resulting influence on the photoluminescence properties of Ca3Si2O7:Tb3+ green-emitting phosphors are investigated in this work. Cross relaxation between activators and energy migration from activators to quenching center, are assigned to be the quenching mechanism for 5D3 emissions and 5D4 emissions of Tb3+ ions, respectively. Concentration quenching processes and the corresponding energy transfer are discussed in detail. The intensity ratio of the emissions from 5D4 to that from 5D3 is tuned by the concentration quenching processes. As a result, bluish-green, green and yellow–green emitting color is induced by concentration quenching effects for Tb3+ ions doped Ca3Si2O7 phosphors. [Copyright &y& Elsevier]

Abstract: Cerium-doped Ca–α-SiAlON phosphors with Ca n−1.5x Si12−m−n Al m+n O n N16−n :Ce x (m=2n, 0.8≤m≤2.4, and 0.02≤x≤0.40) nominal compositions have been synthesized by gas pressure sintering (GPS). The photoluminescence (PL) properties were studied in relation to phase composition, particle morphology, and microstructure. Continuous addition of Ce rare-earth (RE) could enhance the emission intensity of phosphors, which was partially attributed to the formation of increased amount of planar defects where dense doping of Ce ions is achieved. Such enhancement could hold up to x=0.32, above which the emission intensity fell slightly due to the formation of more secondary phases and a surface glassy phase rather than concentration quenching. Finally, possible ways to improve the luminescence properties of Ce-doped α-SiAlON phosphors were discussed through tailoring the composition and microstructure. [Copyright &y& Elsevier]

We consider the renormalization-group evolution of the matrix element of 〈 0 | q ¯ (z) β [ z , 0 ] b (0) α | B ¯ 〉 , which can be used to define the distribution amplitudes for B meson and widely applied in studies of B meson decays. The contribution to the renormalization constant of the non-local operator q ¯ (z) β [ z , 0 ] b (0) α is considered up to one-loop order in QCD. Since the quark fields in this operator are not directly coupled fields, momentum can not flow freely through this non-local operator. Momentum involved in this operator can be treated stringently in coordinate space. We find that the ultraviolet divergences regulated by dimensional parameter ϵ cancel with each other, and the evolution effect vanishes. The matrix element 〈 0 | q ¯ (z) β [ z , 0 ] b (0) α | B ¯ 〉 escapes from the renormalization-group evolution. We then apply the matrix element in calculating B → π transition form factor, where the matrix element is obtained by using the B meson wave function calculated in QCD-inspired potential model. By comparing with experimental data for the semileptonic decay of B → π ℓ ν and light-cone sum rule calculation, we analyze the perturbative and non-perturbative contributions to B → π transition form factor in the frame work of perturbative QCD approach. We find that the effectiveness of the suppression of Sudakov factor to soft contribution depends on the end-point behavior of B meson wave function, and with the B -meson wave function used in this work, soft contribution can not be well suppressed. The hard contribution to the B → π transition form factor is about 59%, and soft contribution can be as large as 41% in the naive calculation. To make the perturbative calculation reliable, a soft momentum cutoff in the calculation and soft form factor have to be introduced. [ABSTRACT FROM AUTHOR]

In this paper, a novel bidirectional backscatter-aided transmission protocol is proposed for wireless powered distributed wearable measurement networks, where we consider channel detection, backscatter-aided wireless power transfer (WPT) and backscatter-aided information transfer. First, the channel detection phase is allocated for both the AP and sensors to get the knowledge of channel state information (CSI) at the beginning of each time block. In the backscatter-aided WPT phase, all sensors harvest radio frequency (RF) energy by converting RF signals from the AP with time-division-multiple-access (TDMA). Finally, the backscatter-aided information transfer phase is allocated to sensors for transmitting their independent information to the AP by TDMA and the harvested energy at each sensor is consumed in this phase. The signals from/to a sensor to/from the AP will be reflected by all other sensors and the optimal reflection coefficient at helping sensors can be calculated according to CSI. Considering fairness among sensors, we maximize sum throughput with energy harvesting constraints and max–min throughput by jointly optimizing the time allocation and the reflection coefficients. Sum and max–min throughput maximization problems are formulated as two convex optimization problems. A low-complexity algorithm is designed to obtain optimal solutions of sum throughput maximization problem with the fairness constraint, and the optimal solutions for max–min throughput maximization are derived as closed-form expressions. Numerical results illustrate the effectiveness of the proposed protocol. [Display omitted] • A novel bidirectional backscatter-aided transmission protocol is proposed. • Sum and max–min throughput maximization problems with fairness constraints are investigated. • The optimal solutions for sum and max–min throughput maximization are obtained. [ABSTRACT FROM AUTHOR]