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An ultrathin and flexible metamaterial absorber (MA) with triple absorption peaks is presented in this paper. The proposed absorber has been designed in such a way that three absorption peaks are located at 8.5, 13.5, and 17 GHz (X and Ku bands) with absorption of 99.9%, 99.5%, and 99.9%, respectively. The proposed structure is only 0.4 mm thick, which is approximately 1/88, 1/55, and 1/44 for the respective free space wavelengths of absorption frequency in various bands. The MA is also insensitive due to its symmetric geometry. In addition, the proposed structure exhibits minimum 86% absorption (TE incidence) within 60° angle of incidence. For TM incidence, the proposed absorber exhibits more than 99% absorptivity up to 60° incidence. Surface current and electric field distributions were investigated to analyze the mechanism governing absorption. Parameter analyses were performed for absorption optimization. Moreover, the performance of the MA was experimentally demonstrated in free space on a sample under test with 20 × 30 unit cells fabricated on a flexible dielectric. Under normal incidence, the fabricated MA exhibits near perfect absorption at each absorption peak for all polarization angles, and the experimental results were found to be consistent with simulation results. Due to its advantages of high-efficiency absorption over a broad range of incidence angles, the proposed absorber can be used in energy harvesting and electromagnetic shielding.

In this work, we propose a broadband, polarization-insensitive and wide incident angle stable metamaterial absorber (MA) based on the resistive film. The absorber consists of a three-layer structure with each layer of dielectric substrate printed with different shapes of resistive film. The multilayer structure not only extends the absorption bandwidth but also maintains high absorption under large wave incident angles. Numerical simulation shows that the absorptivity of a normal incident wave is above 90% in the frequency range 2.34–18.95 GHz, corresponding to a relative absorption bandwidth of 156%. Moreover, the whole MA structure has a total thickness of 11.3 mm, corresponding to 0.09 λ0 at its lowest absorption frequency. Due to the high symmetry of the structure, the absorber has good polarization insensitivity. In addition, for both transverse electric and transverse magnetic incidence, the proposed absorber achieves an absorptivity of more than 80% at incident angles of up to 45° and thus has good stability for wide incident angles. The absorption principle of the absorber is analyzed by the surface current and power loss density distribution. Parameter analysis is also performed for bandwidth optimization. Due to its advantages of wideband absorption with high efficiency, the proposed absorber has the potential to be applied to the energy-harvesting and electromagnetic stealth fields.

Background The rapid growth of social media as an information channel has made it possible to quickly spread inaccurate or false vaccine information, thus creating obstacles for vaccine promotion. Objective The aim of this study is to develop and evaluate an intelligent automated protocol for identifying and classifying human papillomavirus (HPV) vaccine misinformation on social media using machine learning (ML)–based methods. Methods Reddit posts (from 2007 to 2017, N=28,121) that contained keywords related to HPV vaccination were compiled. A random subset (2200/28,121, 7.82%) was manually labeled for misinformation and served as the gold standard corpus for evaluation. A total of 5 ML-based algorithms, including a support vector machine, logistic regression, extremely randomized trees, a convolutional neural network, and a recurrent neural network designed to identify vaccine misinformation, were evaluated for identification performance. Topic modeling was applied to identify the major categories associated with HPV vaccine misinformation. Results A convolutional neural network model achieved the highest area under the receiver operating characteristic curve of 0.7943. Of the 28,121 Reddit posts, 7207 (25.63%) were classified as vaccine misinformation, with discussions about general safety issues identified as the leading type of misinformed posts (2666/7207, 36.99%). Conclusions ML-based approaches are effective in the identification and classification of HPV vaccine misinformation on Reddit and may be generalizable to other social media platforms. ML-based methods may provide the capacity and utility to meet the challenge involved in intelligent automated monitoring and classification of public health misinformation on social media platforms. The timely identification of vaccine misinformation on the internet is the first step in misinformation correction and vaccine promotion.

This study proposes and experimentally demonstrates enhanced broadband absorption with twisted multilayer metal–dielectric stacking. Compared with the traditional metal–dielectric pyramid, the resonance frequencies of the third-order magnetic resonances in the twisted quadrangular frustum redshifted obviously. Hence, the proposed structure enables an ultra-broadband absorption by combining the third-order magnetic resonances with the fundamental mode. The broadband absorption is insensitive to the incident wave polarization, whereas the twisted angle of the stacking plays an important role in deciding the absorption bandwidth. The sample was fabricated via the multi-material hybrid micro-droplet jetting modeling (MHMJM) technology to verify the enhanced absorbing performance. The measured results suggest that the proposed strategy provides a potential path to realize broadband electromagnetic wave absorption. Moreover, it is possible to extend the twisted metamaterial to the terahertz and infrared frequencies using the advanced nano fabrication techniques.

In this work, a single-band metamaterial absorber (MA) based on a three dimensional (3D) resonant structure is presented. The unit cell is composed of a standing gear-shaped resonator, which is embedded in the dielectric substrate. The proposed 3D MA is ultrathin with a total thickness of 2.3 mm, corresponding 0.077λ0 at its center frequency. The simulation results demonstrate a high absorption peak at 10.1 GHz with absorptivity of 99.9%. The proposed 3D MA is insensitive to the polarization of the incident wave due to its rotationally symmetric structure. Moreover, the proposed 3D MA exhibits a wide-incident-angle stability, as absorptivity of more than 85% can be achieved for both TE and TM incidences with incident angle up to 60°. Most importantly, multiband electromagnetic wave absorption of the stereo MA can be enabled by adjusting the structural parameters of the standing gear. The proposed structure is compatible with 3D printing technology and has potential applications in electromagnetic shielding.

This study aimed to compare the performance of the BD FACSPresto system with the conventional standard-of-care technologies for the measurement of absolute CD4 count (AbsCD4), CD4 percentage (CD4%) and total hemoglobin concentration (Hb) in capillary and venous blood samples of HIV-negative and HIV-positive subjects. A total of 1304 participants were included in this prospective cohort study. Both venous and capillary blood samples were analyzed using the BD FACSPresto system and the results were compared against the BD FACSCalibur for enumerating AbsCD4 and CD4% and Sysmex XT-4000i hematology analyzer for determining Hb levels. Method comparison studies were performed using Deming regression and Bland–Altman plots. The Deming regression analyses comparing the accuracy of the BD FACSPresto system with the reference standard technologies demonstrated a significant linear correlation between the AbsCD4, CD4%, and Hb values generated by the two platforms. The 95% CI of the slopes for AbsCD4, CD4%, and Hb levels were 0.94–0.99, 0.99–1.01 and 0.86–0.93, respectively (P

Ranking is a core task in recommender systems, which aims at providing an ordered list of items to users. Typically, a ranking function is learned from the labeled dataset to optimize the global performance, which produces a ranking score for each individual item. However, it may be sub-optimal because the scoring function applies to each item individually and does not explicitly consider the mutual influence between items, as well as the differences of users' preferences or intents. Therefore, we propose a personalized re-ranking model for recommender systems. The proposed re-ranking model can be easily deployed as a follow-up modular after any ranking algorithm, by directly using the existing ranking feature vectors. It directly optimizes the whole recommendation list by employing a transformer structure to efficiently encode the information of all items in the list. Specifically, the Transformer applies a self-attention mechanism that directly models the global relationships between any pair of items in the whole list. We confirm that the performance can be further improved by introducing pre-trained embedding to learn personalized encoding functions for different users. Experimental results on both offline benchmarks and real-world online e-commerce systems demonstrate the significant improvements of the proposed re-ranking model.

Recommendation with multiple objectives is an important but difficult problem, where the coherent difficulty lies in the possible conflicts between objectives. In this case, multi-objective optimization is expected to be Pareto efficient, where no single objective can be further improved without hurting the others. However existing approaches to Pareto efficient multi-objective recommendation still lack good theoretical guarantees. In this paper, we propose a general framework for generating Pareto efficient recommendations. Assuming that there are formal differentiable formulations for the objectives, we coordinate these objectives with a weighted aggregation. Then we propose a condition ensuring Pareto efficiency theoretically and a two-step Pareto efficient optimization algorithm. Meanwhile the algorithm can be easily adapted for Pareto Frontier generation and fair recommendation selection. We specifically apply the proposed framework on E-Commerce recommendation to optimize GMV and CTR simultaneously. Extensive online and offline experiments are conducted on the real-world E-Commerce recommender system and the results validate the Pareto efficiency of the framework. To the best of our knowledge, this work is among the first to provide a Pareto efficient framework for multi-objective recommendation with theoretical guarantees. Moreover, the framework can be applied to any other objectives with differentiable formulations and any model with gradients, which shows its strong scalability.

Features play an important role in the prediction tasks of e-commerce recommendations. To guarantee the consistency of off-line training and on-line serving, we usually utilize the same features that are both available. However, the consistency in turn neglects some discriminative features. For example, when estimating the conversion rate (CVR), i.e., the probability that a user would purchase the item if she clicked it, features like dwell time on the item detailed page are informative. However, CVR prediction should be conducted for on-line ranking before the click happens. Thus we cannot get such post-event features during serving. We define the features that are discriminative but only available during training as the privileged features. Inspired by the distillation techniques which bridge the gap between training and inference, in this work, we propose privileged features distillation (PFD). We train two models, i.e., a student model that is the same as the original one and a teacher model that additionally utilizes the privileged features. Knowledge distilled from the more accurate teacher is transferred to the student to improve its accuracy. During serving, only the student part is extracted and it relies on no privileged features. We conduct experiments on two fundamental prediction tasks at Taobao recommendations, i.e., click-through rate (CTR) at coarse-grained ranking and CVR at fine-grained ranking. By distilling the interacted features that are prohibited during serving for CTR and the post-event features for CVR, we achieve significant improvements over their strong baselines. During the on-line A/B tests, the click metric is improved by +5.0% in the CTR task. And the conversion metric is improved by +2.3% in the CVR task. Besides, by addressing several issues of training PFD, we obtain comparable training speed as the baselines without any distillation., 9 pages

OBJECTIVES: The study aimed to investigate the levels of RRR-α-tocopherol and carotenoids in maternal blood, cord blood and breast milk samples of different lactation stages from healthy Chinese mothers and to explore their associations with social demographical characteristics. METHODS: The study was part of a MUAI study (Maternal Nutrition and Infant Investigation, ChiCTR1800015387). SAMPLES COLLECTION: Healthy lactating mothers (aged 20–35 year) with single, full-term delivery were recruited in Tianjin city. Maternal blood, cord blood, colostrum, transitional milk and mature milk samples were collected. SAMPLE ANALYSIS: The levels of tocopherols and carotenoids (lutein, zeaxanthin, β-cryptoxanthin, β-carotene,lycopene) were determined by HPLC. The compositions of α-tocopherol stereoisomers were determined by chiral HPLC. RESULTS: Maternal blood plasma contained higher α-tocopherol level than cord blood plasma and breast milk samples. In breast milk samples, the levels of α-tocopherol reduced with lactation stages for about three times. Even though the levels of α-tocopherol varied in plasma and breast milk, RRR-α-tocopherol (RRR) were predominant in all samples, accounting for 83%∼90% of α-tocopherol. The results suggestted RRR was preferred stereoisomers for maternal and newborn. Carotenoids were also more abundant in maternal blood plasma than in cord blood plasma and breast milk samples. The total carotenoids level in maternal blood plasma was about 8 times higher than cord blood plasma and 2.5 times of colostrum. The level of total carotenoids decreased with the lactation stages due to the dramatically dropped of lycopene and β-carotene. In contrast, lutein level remained stable in breast milk and was the most abundant carotenoids in transitional milk, mature milk and blood plasma, suggesting that fetus and infant had continuous demand for lutein. The levels of carotenoids and RRR in maternal and cord blood plasma were related to parity, pre-pregnancy and prenatal BMI. The levels of carotenoids and RRR in breast milk samples were correlated with cord plasma. CONCLUSIONS: RRR- α-tocopherol and lutein were the most abundant α-tocopherol and carotenoids in Chinese cord blood plasma and breast milk, suggesting that they may play more important roles in early life. FUNDING SOURCES: This study was funded by Abbott Nutrition R&D Centre, Shanghai, China.

In this work, an ultra-broadband and polarization-insensitive metamaterial absorber (MA) with high optical transparency is presented. Indium-tin-oxide (ITO) films are used as frequency selective surfaces in multiple conductive layers and also as the reflective backplane. Numerical simulation analysis demonstrates that the absorptivity of the proposed absorber exceeds 90% in the frequency range from 10 to 75.5 GHz, corresponding to a relative absorption bandwidth of 153%. The proposed structure has a total thickness of 2.9 mm, which is approximately 1/10 of the free space wavelength of its lowest operating frequency. The absorber also has good polarization insensitivity due to its symmetric geometry. Moreover, for TE-polarized waves, the proposed absorber can maintain an absorptivity greater than 70% for frequencies ranging from 10 to 80 GHz as the incident angle is increased to 45°. For TM-polarized waves, it provides absorptivity of more than 80% at incident angles up to 60°. Surface current distribution on each conductive ITO layer was simulated to analyze the absorption mechanism of the MA. A prototype composed of 16 × 16 unit cells was fabricated and the experimental results show a good agreement with the numerical simulations. Due to its ultra-wideband absorption and wide-incident-angle stability, the proposed MA has potential value in electromagnetic applications such as optically transparent EM shielding and microwave radiation protection.

We propose a dual-band metamaterial absorber (MA) based on a stereo resonant structure. The unit cell of the proposed MA is composed of double metallic rings with a rampart on each ring into a dielectric substrate. In contrast to the conventional plane resonator, our proposed metamaterial exhibits wider incident angle stability. The power loss density distribution shows that the standing ramparts play a key role in enhancing the electromagnetic wave absorption. Experimental results verify the wide-incident-angle stability of the absorber. Our proposed strategy paves a new way on developing MAs with wide incident angle stabilities.

In this paper, we investigate a novel efficient metasurface-based wideband cross-polarization converter. The device rotates the y-polarized electromagnetic (EM) wave into an x-polarized EM-wave for a wide range of wavelengths (9.8 GHz–18.9 GHz) and vice versa. The unit cell of the proposed converter is very small and consists of four metal/dielectric layers. The asymmetric resonators represent a solid base to allow higher conversion efficiencies, while the slightly varying magnetic and electric resonances between neighboring layers produce a broad operating frequency range. Furthermore, only additive manufacturing technology was used, which offers a low-cost and simple solution to produce the complicated multilayer device. Both measured and simulated results are in good agreement confirming the excellent performance. This study can help both the affordable design and fabrication of multilayer wideband polarization converters in the future.

α-Melanocyte-stimulating hormone (α-MSH) is a tridecapeptide derived from pro-opiomelanocortin that exhibits potent anti-inflammatory properties by regulating the production of inflammatory mediators. This peptide has been well established in several inflammatory models, including inflammatory bowel disease (IBD). However, its extremely short duration in vivo limits its clinical application. To address this limitation, Bifidobacterium was used here as a carrier to deliver α-MSH. We utilized α-MSH-engineered Bifidobacterium against IBD, which is closely linked to immune and intestinal microbiota dysfunction. First, we constructed a Bifidobacterium longum secreting α-MSH (B. longum-α-MSH). We then tested the recombinant α-MSH expression and determined its bioactivity in HT-29 cells. To assess its effectiveness, B. longum-α-MSH was used against an ulcerative colitis (UC) model in rats induced by dextran sulfate sodium. The data showed that α-MSH expression in B. longum-α-MSH was effective, and its biological activity was similar to the synthesized one. This UC model experiment indicated that B. longum-α-MSH successfully colonized the intestinal gut, expressed bioactive α-MSH and had a significant anti-inflammatory effect. The results demonstrate the feasibility of preventing IBD by using B. longum-α-MSH.

In this article, a wideband, polarization-insensitive, and wide-incident-angle stable absorber based on conductive ink frequency selective surface is presented. The presented absorber is compatible with screen printing technology. The design and absorption principle of the proposed absorber is presented, and simulation analysis is conducted. The simulation results show that in the frequency range 6.58–16.38 GHz, the absorptivity of the proposed absorber is greater than 90%, while the relative absorption bandwidth is 85.4%. The whole absorber structure is relatively thin, having a total thickness of 3.3 mm, corresponding to 0.126λ0 at its center frequency. In addition, for both transverse electric and transverse magnetic incident waves, the proposed absorber achieves the absorptivity of more than 80% at the incident angle of up to 45°. A prototype of the proposed absorber is fabricated and used in experimental verification. The obtained experimental results show a good agreement with the numerical simulations. This absorber has great potential applications in the field of microwave sensing and absorbing.

Background Long-term administration of α-lipoic acid (α-LA) is proved to ameliorate renal impairment. Herein we assessed serum, urinary biomarkers and vascular endothelium function to evaluate its short-period therapeutic effect and identify novel biomarkers for diabetic nephropathy (DN). Methods Sixty-two microalbuminuria-stage DN patients were randomly divided into two groups and received the following treatment for 8 weeks: (1) routine treatment(DM group); (2) routine treatment with 600 mg/d α-lipoic acid intravenously (α-LA group). Another total of 21 patients were recruited for the second-stage study and randomly divided into two groups: normoalbuminuria (UAER

Drug resistance constitutes one of the main obstacles for clinical recovery of acute myeloid leukemia (AML) patients. Therefore, the treatment of AML requires new strategies, such as adding a third drug. To address whether GATA2 could act as a regulator of chemotherapy resistance in human leukemia cells, we observed KG1a cells and clinical patients' AML cells with a classic drug (Cerubidine) and Gefitinib. After utilizing chemotherapy, the expression of GATA2 and its target genes (EVI, SCL and WT1) in surviving AML cells and KG1a cells were significantly enhanced to double and quadrupled compared to its original level respectively. Furthermore, with continuous chemotherapeutics, AML cells with GATA2 knockdown or treated with GATA2 inhibitor (K1747) almost eliminated with dramatically reduced expression of WT1, SCL, EVI, and significantly increased apoptotic population. Therefore, we propose that reducing GATA2 expression or inhibition of its transcription activity can relieve the drug resistance of acute myeloid leukemia cells and it would be helpful for eliminating the leukemia cells in patients.

Drug resistance constitutes one of the main obstacles for clinical recovery of acute myeloid leukemia (AML) patients. Therefore, the treatment of AML requires new strategies, such as adding a third drug. To address whether GATA2 could act as a regulator of chemotherapy resistance in human leukemia cells, we observed KG1a cells and clinical patients' AML cells with a classic drug (Cerubidine) and Gefitinib. After utilizing chemotherapy, the expression of GATA2 and its target genes (EVI, SCL and WT1) in surviving AML cells and KG1a cells were significantly enhanced to double and quadrupled compared to its original level respectively. Furthermore, with continuous chemotherapeutics, AML cells with GATA2 knockdown or treated with GATA2 inhibitor (K1747) almost eliminated with dramatically reduced expression of WT1, SCL, EVI, and significantly increased apoptotic population. Therefore, we propose that reducing GATA2 expression or inhibition of its transcription activity can relieve the drug resistance of acute myeloid leukemia cells and it would be helpful for eliminating the leukemia cells in patients.

The use of bisphosphonates and the risk of esophageal cancer have recently received increasing concern and related studies have yielded controversial results. The present meta-analysis of observational studies shows that no clear association between bisphosphonate treatment and risk of esophageal cancer was observed. Epidemiological evidence suggests that bisphosphonate treatment can increase the risk of esophageal cancer. However, data on this issue are unstable and controversial. We conducted a meta-analysis to provide a quantitative assessment of the association between use of bisphosphonates and risk of esophageal cancer. We searched the Medline and Embase databases up to May 2012 to identify studies related to bisphosphonates and esophageal cancer. Summary effect estimates with 95 % confidence intervals (CI) were derived using a fixed or random effects model, depending on the heterogeneity of the included studies. Seven epidemiologic studies that consisted of four cohort studies and three case–control studies were included in this meta-analysis. In our primary analysis, bisphosphonate treatment was not associated with risk of esophageal cancer in both cohort studies [pooled relative risk (RR) 1.23, 95 % CI 0.79–1.92] and case–control studies [pooled odds ratio (OR) 1.24, 95 % CI 0.98–1.57]. Evidence for the presence of significant heterogeneity was found in cohort studies (p = 0.009, I 2 = 74 %) but not in case–control studies (p = 0.338, I 2 = 7.8 %). In our secondary analysis, no significant increased risk of esophageal cancer was found in alendronate users (pooled RR 1.08, 95 % CI 0.67–1.75 in cohort studies; pooled OR 1.16, 95 % CI 0.82–1.63 in case–control studies). Based on current evidences, bisphosphonate treatment was not significantly associated with excess risk of esophageal cancer.

Recently, a number of studies have demonstrated the potential beneficial role for novel anti-diabetic GLP-1 receptor agonists (GLP-1RAs) in the skeleton metabolism in diabetic rodents and patients. In this study, we evaluated the impacts of the synthetic GLP-1RA Liraglutide on bone mass and quality in osteoporotic rats induced by ovariectomy (OVX) but without diabetes, as well as its effect on the adipogenic and osteoblastogenic differentiation of bone marrow stromal cells (BMSCs). Three months after sham surgery or bilateral OVX, eighteen 5-month old female Wistar rats were randomly divided into three groups to receive the following treatments for 2 months: (1) Sham + normal saline; (2) OVX + normal saline; and (3) OVX + Liraglutide (0.6 mg/day). As revealed by micro-CT analysis, Liraglutide improved trabecular volume, thickness and number, increased BMD, and reduced trabecular spacing in the femurs in OVX rats; similar results were observed in the lumbar vertebrae of OVX rats treated with Liraglutide. Following in vitro treatment of rat and human BMSCs with 10 nM Liraglutide, there was a significant increase in the mRNA expression of osteoblast-specific transcriptional factor Runx2 and the osteoblast markers alkaline phosphatase (ALP) and collagen α1 (Col-1), but a significant decrease in peroxisome proliferator-activated receptor γ (PPARγ). In conclusion, our results indicate that the anti-diabetic drug Liraglutide can exert a bone protective effect even in non-diabetic osteoporotic OVX rats. This protective effect is likely attributable to the impact of Liraglutide on the lineage fate determination of BMSCs.

Emerging epidemiological evidence suggest an association between metabolic syndrome and fractures. However, whether metabolic syndrome is an independent risk or protective factor of fractures remains controversial. Our goal is to provide a quantitative assessment of the association between metabolic syndrome and bone fractures by conducting a meta-analysis of observational studies. The PubMed and Embase database were searched through to March 2013 to identify studies that met pre-established inclusion criteria. Reference lists of retrieved articles were also reviewed. Summary effect estimates with 95% confidence intervals (CI) were derived using a fixed or random effects model, depending on the heterogeneity of the included studies. Eight epidemiologic studies involving 39,938 participants were included in the meta-analysis. In overall analysis, metabolic syndrome was not associated with prevalent fractures [pooled odds ratio (OR) 0.93, 95% CI 0.84 - 1.03] in cross-sectional studies or incident fractures [pooled relative risk (RR) 0.88, 95% CI 0.37 - 2.12] in prospective cohort studies. No evidence of heterogeneity was found in cross-sectional studies (p = 0.786, I 2 = 0.0%). A substantial heterogeneity was detected in cohort studies (p = 0.001, I 2 = 85.7%). No indication of significant publication bias was found either from Begg’s test or Egger’s test. Estimates of total effects were substantially consistent in the sensitivity and stratification analyses. The present meta-analysis of observational studies suggests that the metabolic syndrome has no explicit effect on bone fractures.