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Atrial natriuretic peptide (ANP) plays a pivotal role in the regulation of the cardiovascular system. The ANP level increases during atrial fibrillation (AF), suggesting that AF may provoke ANP secretion, but its potential mechanism is still unclear. In the present study, the potential mechanisms of rapid atrial pacing (RAP) regulating ANP secretion was explored. Rabbits were subjected to burst RAP, ANP secretion increased whereas cyclic guanosine monophosphate (cGMP) concentrations decreased during RAP. The p-Akt and p-GSK-3β levels decreased in atrial tissues. Natriuretic peptide receptor A (NPR-A) protein and particulate guanylate cyclase (PGC) activity were detected. The sensitivity of NPR-A to ANP decreased, leading to the decrease of PGC activity. Also, the isolated atrial perfusion system were made in the rabbit model, cGMP was shown to inhibit ANP secretion, and the Akt inhibitor LY294002 (LY) and GSK-3β inhibitor SB216763 (SB) attenuated the inhibitory effects of cGMP on ANP secretion and enhanced the inhibitory effects of cGMP on atrial dynamics. In conclusion, NPR-A interacts with ANP to regulate PGC expression, and influence the expression of cGMP during RAP, which involves in the Akt/GSK-3β signaling pathway. From the aforementioned points we conclude that cGMP regulates ANP secretion by the Akt/GSK-3β signaling pathway during atrial pacing.

In this paper 1-bit dual-polarized ultra-thin lens antennas are presented based on Huygens’ principle. The unit cell provides two-state transmission phase compensation for dual-polarized waves. By tuning state 0 away from resonance and state 1 near Huygens’ resonance, the 180° transmission phase difference between the two states is achieved. In the frequency range of 27.5–28.5 GHz, the transmission phase difference between the two states of the unit cell is 180° ± 20°, and the transmission amplitude is greater than −2 dB. Using the proposed unit cell, three ultrathin 1-bit Huygens’ metasurface antennas comprising 33 × 33 unit cells with single beams pointing separately at 0°, 15°, and 30° are designed, fabricated and measured. Simulated and measured results show that the proposed 1-bit transmitarray antenna can achieve single-beam patterns, which is useful for the development of reconfigurable transmission and digital metasurface antennas in the future.

In this paper, a dual-polarized Huygens unit is proposed, which has a double-layer metallic pattern etched on both sides of one dielectric substrate. Induced magnetism enables the structure to support Huygens’ resonance, thus obtaining nearly complete available transmission phase coverage. By optimizing the structural parameters, a better transmission performance can be achieved. When the Huygens metasurface was used for the design of a meta-lens, good radiation performance was exhibited, with a maximum gain of 31.15 dBi at 28 GHz, an aperture efficiency of 42.7% and a 3 dB gain bandwidth of 26.4 GHz to 30 GHz (12.86%). Due to its excellent radiation performance and very simple fabrication, this Huygens meta-lens has important applications in millimeter-wave communication systems.

Terahertz wavefront manipulation is one of the key terahertz technologies. While few of the research works on terahertz wavefront manipulation has broadband and dual-polarized responses. Here a broadband dual-polarized Huygens’ metasurface is proposed to realize high efficient terahertz wave anomalous refraction. By constructing simultaneous electric and magnetic responses in a bi-layer metasurface to produce Huygens’ resonance, broadband and large phase changes for dual-polarized terahertz wave are achieved. A phase change over 300° with transmission magnitude beyond 0.75 is realized between 0.4 THz and 1 THz. An array made of the metasurface with phase gradient is designed to achieve a 14.0° anomalous refraction for two orthogonal linear polarized waves at 0.93 THz. The structure consists of only two metal layers, providing a simple and high-efficiency design scheme for achieving efficient dual-polarized terahertz wavefront manipulation.

BackgroundUpper limb motor dysfunction caused by stroke greatly affects the daily life of patients, significantly reduces their quality of life, and places serious burdens on society. As an emerging rehabilitation training method, brain–computer interface (BCI)–based training can provide closed-loop rehabilitation and is currently being applied to the restoration of upper limb function following stroke. However, because of the differences in the type of experimental clinical research, the quality of the literature varies greatly, and debate around the efficacy of BCI for the rehabilitation of upper limb dysfunction after stroke has continued.ObjectiveWe aimed to provide medical evidence-based support for BCI in the treatment of upper limb dysfunction after stroke by conducting a meta-analysis of relevant clinical studies.MethodsThe search terms used to retrieve related articles included “brain-computer interface,” “stroke,” and “upper extremity.” A total of 13 randomized controlled trials involving 258 participants were retrieved from five databases (PubMed, Cochrane Library, Science Direct, MEDLINE, and Web of Science), and RevMan 5.3 was used for data analysis.ResultsThe total effect size for BCI training on upper limb motor function of post-stroke patients was 0.56 (95% CI: 0.29–0.83). Subgroup analysis indicated that the standard mean differences of BCI training on upper limb motor function of subacute stroke patients and chronic stroke patients were 1.10 (95% CI: 0.20–2.01) and 0.51 (95% CI: 0.09–0.92), respectively (p = 0.24).ConclusionBrain–computer interface training was shown to be effective in promoting upper limb motor function recovery in post-stroke patients, and the effect size was moderate.

Applications of zerovalent iron (ZVI) for water treatment under aerobic conditions include sequestration of metals (e.g., in acid mine drainage) and decolorization of dyes (in wastewaters from textile manufacturing). The processes responsible for contaminant removal can be a complex mixture of reduction, oxidation, sorption, and coprecipitation processes, which are further complicated by the dynamics of oxygen intrusion, mixing, and oxide precipitation. To better understand such systems, the removal of an azo dye (Orange I) by micron-sized granular ZVI at neutral pH was studied in open (aerobic) stirred batch reactors, by measuring the kinetics of Orange I decolorization and changes in "geochemical" properties (DO, Fe(II), and Eh), with and without two treatments that might improve the long-term performance of this system: sulfidation by pretreatment with sulfide and magnetization by application of a weak magnetic field (WMF). The results show that the changes in solution chemistry are coupled to the dynamics of oxygen intrusion, which was modeled as analogous to dissolved oxygen sag curves. Both sulfidation and magnetization increased Orange I removal rates 2.4-71.8-fold, but there was little synergistic benefit to applying both enhancements together. Respike experiments showed that the enhancement from magnetization carries over from magnetization to sulfidation, but not the reverse. [ABSTRACT FROM AUTHOR]

Meeting the regulatory discharge standards for pulp and paper mill wastewater has become ever more difficult because of its recalcitrant and colored dissolved organic matter (DOM). In this study, the variation of DOM from the secondary effluent of pulp and paper mill wastewater before and after coagulation was investigated based on hydrophobicity/hydrophilicity, apparent molecular weight (MW) and fluorescence. DOM fractions of the secondary effluent were all with the apparent MW <20 kDa. Particularly, the hydrophobic acids (HOA) fraction, mainly composed of humic-like materials, was the major component, and it also had the highest color and SUVA254 (UV254 to dissolved organic carbon ratio). Hydrophilic bases (HIB) and hydrophilic neutrals (HIN) fractions were the other important parts besides HOA. Coagulation can remove all DOM fractions to different extent, and it was more effective for organic compounds with MW > 5 kDa. The removal efficiencies of humic-like, fulvic-like and soluble microbial by-product-like constituents in HOA and HIB fractions were much higher than in other fractions. Even so, the coagulation effluent still contained large amounts of contaminants with complicated fluorophores and apparent MW <5 kDa, and HOA and HIN fractions were also the major parts in the coagulation effluent. [ABSTRACT FROM AUTHOR]

Many oxyanion-forming metals (As, Sb, Se, Tc, etc.) can be removed from water by adsorption and/or redox reactions involving iron oxides, including the oxides associated with zerovalent iron (ZVI). The rate of antimonite (Sb(III) hydrolysis species) removal by ZVI was determined in open, well-mixed batch reactors as a function of experimental factors, including aging of the ZVI, addition of Fe(II), Sb dose, mixing rate, pH, initial concentrations of Sb(III), etc. However, the largest effect observed was the roughly 6-8 fold increase in Sb(III) removal rate due to the application of a weak magnetic field (WMF) during the experiments. The WMF effect on Sb removal arises from stimulated corrosion and delayed passivation of the ZVI, as evidenced by time series correlation analysis of "geochemical" properties (DO, Fetot, Eh, and pH) measured synchronously in each experiment. The removal of Sb under the conditions of this study was mainly due to oxidation of Sb(III) to Sb(V) and adsorption and coprecipitation onto the iron oxides formed from accelerated corrosion of ZVI, as evidenced by Sb K-edge XANES, EXAFS, and XPS. The degree of the WMF enhancement for Sb(III) was found to be similar to the WMF effect reported previously for Sb(V), As(III), As(V), and Se(VI). [ABSTRACT FROM AUTHOR]

Highly conductive silver-coated glass fiber (GF) was fabricated in an efficient and environment-friendly way. When the GF powder was immersed in dopamine solution, an adherent self-polymerized poly(dopamine) (PDA) layer was formed on the GF surface. PDA acts as both a linker between GF and silver nanoparticles and a reducing agent for reducing silver ions to metallic silver. The silver nanoparticles can be chemically bound to the catechol and amine functional groups in PDA by electroless plating using glucose as reducing agent. Chemical and physical characterizations of the silver-coated GF were carried Out by using X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Four-point probe was used to study the electrical resistivity of the silver-coated glass fibers. The results indicated that the silver coated on the GF surface was compact, uniform, continuous, and in a metallic crystal state. The silver content could be well controlled from 9.5 to 24 wt% by adjusting the reduction conditions. The electrical resistivity of the silver-coated glass fibers could be as low as 1.0 mΩ cm. [ABSTRACT FROM AUTHOR]

To reduce phosphorus waste water from phosphate buffers, we utilized weak-base beads as eco-friendly and reusable buffer agents for the pH control of urease-catalyzed reactions. [ABSTRACT FROM AUTHOR]

Soluble tumor necrosis factor alpha (TNF-α) receptors contain two receptors: soluble tumor necrosis factor receptor (sTNFR) 1 and 2, and the aim of our study was to discover their concentration and diagnostic value for idiopathic membranous nephropathy (IMN). In total, 58 patients with IMN, 51 patients with chronic kidney disease (CKD), and 30 healthy volunteers were enrolled in this study. Levels of serum sTNFR1 and sTNFR2 were determined by enzyme-linked immunosorbent assay (ELISA). Serum cystatin C (CysC), urea, creatinine (CREA), uric acid (UA), total protein (TP), albumin (ALB), and 24-h urinary protein (proteinuria, PRO) were examined by automatic biochemical analyzer. Levels of sTNFR1 and sTNFR2 were significantly higher in IMN group than CKD and control group ( P

Ω-shaped copper specimens are oxidized in wet air. The results show that totally no-wire structure, CuO whiskers, and the high density of well-aligned CuO nanowires can be formed simultaneously on the different positions of the specimen. A three-dimensional flow simulation results indicate that the direction of velocity vectors of local gas flow affects the alignment of nanowires during oxidation while the shear stress of flowing gas near the surface of a Ω-shaped specimen controls the density of nanowires. [ABSTRACT FROM AUTHOR]

We report here the synthesis and highly substrate-site selective growth behavior of graphite microrods cored with silica nanowires by chemical vapor deposition. This technique allows us to deposit vertically aligned microrods preferentially on silicon regions of patterned SiO2/Si substrates. One might also transform the microrods into other forms, for example, into microtubes of graphite and/or α-Fe2O3 nanoparticles by some chemical and/or physical routes. The structure and the growth mechanism of the graphite microrods were investigated and discussed. [ABSTRACT FROM AUTHOR]

Dipeptidyl peptidase-4 (DPP4) is one of the most potent mammalian serine proteases participated in the pathogenesis of subclinical atherosclerosis. Here we investigated whether the plasma soluble form of DPP4 is associated with the prevalence of coronary artery disease (CAD) with and without diabetes mellitus (DM). A cross-sectional study was conducted of 496 aged 26-81 years with (n = 362) and without (n = 134) CAD. Plasma DPP4 activity, high sensitive C-reactive protein (hs-CRP), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein levels were measured. The coronary atherosclerotic plaques were evaluated by coronary angiography. The CAD patients with (n = 84) and without (n = 278) DM had significantly higher DPP4 levels (11.8 ± 3.1 vs. 6.9 ± 3.5 ng/mL, P

Metals have many extraordinary optical properties. However, thick metals are nice mirrors, which prevent light penetrating deep into them. Since the skin depth is very thin, most optical properties of bulk metals are unavailable. In this paper, we review the way of reducing reflections in thick metal slabs by coating dielectric photonic crystals, based on the light-tunneling mechanism in metamaterials. Owing to the boost of local fields in the metals, many optical effects such as nonlinear effects, optical extinction (absorption) and optical rotation are greatly enhanced in these simple structures. The enhancement of optical effects in thick metals may be very useful in some optical devices including optical switches and diodes, absorbers, insulators and so on.

Dynamic membrane has attractive features, compared to the traditional membrane technology. This work investigated the performance and filtration process of a dynamic membrane (DM) at a constant flow rate, which was formed by flocs, produced by river water pollutants reacting with poly aluminum chloride with a non-woven fabric filter as the support media. Effluent turbidity was studied as the marker of a dynamic membrane formation, and chemical oxygen demand (COD) and total phosphorus (TP) were surveyed to evaluate the process performance. The results showed that the combined coagulation--dynamic membrane process is effective in treating polluted river water. The COD and TP removal efficiencies were obtained in the DM forming process and after formation. The relationship of the running pressure versus the operation time was used to evaluate the filtration process, according to the combined models of the membrane fouling. The standard model plays the dominant role in the first stage of the DM reactor running process, and after it, the intermediate model plays the leading role. [ABSTRACT FROM AUTHOR]

An abstract of the article "Covalent Attachment of Organic Groups onto Single-walled Carbon Nanotubes via Copper(I)-promoted Radical Addition," by Yongsheng Li, Chunhua Xu, and Yaomin Xu is presented.

Follistatin (FS)-like 1 (FSTL1) is a member of the FSSPARC (secreted protein, acidic and rich in cysteine) family of secreted and extracellular matrix proteins. The functions of FSTL1 have been studied in heart and lung injury as well as in wound healing; however, the role of FSTL1 in the kidney is largely unknown. Here, we show using single-cell RNA-Seq that Fstl1 was enriched in stromal cells in obstructed mouse kidneys. In addition, immunofluorescence demonstrated that FSTL1 expression was induced in fibroblasts during kidney fibrogenesis in mice and human patients. We demonstrate that FSTL1 overexpression increased renal fibrosis and activated the Wnt/ß-catenin signaling pathway, known to promote kidney fibrosis, but not the transforming growth factor ß (TGF-ß), Notch, Hedgehog, or Yes-associated protein (YAP) signaling pathways in obstructed mouse kidneys, whereas inhibition of FSTL1 lowered Wnt/ß-catenin signaling. Importantly, we show that FSTL1 interacted with Wnt ligands and the Frizzled (FZD) receptors but not the coreceptor lipoprotein receptor-related protein 6 (LRP6). Specifically, we found FSTL1 interacted with Wnt3a through its extracellular calcium-binding (EC) domain and von Willebrand factor type C-like (VWC) domain, and with FZD4 through its EC domain. Furthermore, we show that FSTL1 increased the association of Wnt3a with FZD4 and promoted Wnt/β-catenin signaling and fibrogenesis. The EC domain interacting with both Wnt3a and FZD4 also enhanced Wnt3a signaling. Therefore, we conclude that FSTL1 is a novel extracellular enhancer of the Wnt/ß-catenin pathway. [ABSTRACT FROM AUTHOR]

Deqi sensation, a psychophysical response characterized by a spectrum of different needling sensations, is essential for Chinese acupuncture clinical efficacy. Previous research works have investigated the component of Deqi response upon acupuncture on acupoints on the trunk and limbs. However, the characteristics of Deqi sensations of transcutaneous electrical nerve stimulation (TENS) on auricular points are seldom reported. In this study, we investigated the individual components of Deqi during TENS on auricular concha area and the superior scapha using quantitative measurements in the healthy subjects and depression patients. The most striking characteristics of Deqi sensations upon TENS on auricular points were tingling, numbness, and fullness. The frequencies of pressure, warmness, heaviness, and soreness were relatively lower. The dull pain and coolness are rare. The characteristics of Deqi were similar for the TENS on concha and on the superior scapha. [ABSTRACT FROM AUTHOR]

Single-molecule Förster resonance energy transfer is widely applied to study helicases by detecting distance changes between a pair of dyes anchored to overhangs of a forked DNA. However, it has been lacking single-base pair (1-bp) resolution required for revealing stepping kinetics of helicases. We designed a nanotensioner in which a short DNA is bent to exert force on the overhangs, just as in optical or magnetic tweezers. The strategy improved the resolution of Förster resonance energy transfer to 0.5 bp, high enough to uncover differences in DNA unwinding by yeast Pif1 and E. coli RecQ whose unwinding behaviors cannot be differentiated by currently practiced methods. We found that Pif1 exhibits 1-bp-stepping kinetics, while RecQ breaks 1 bp at a time but sequesters the nascent nucleotides and releases them randomly. The high-resolution data allowed us to propose a three-parameter model to quantitatively interpret the apparently different unwinding behaviors of the two helicases which belong to two superfamilies. [ABSTRACT FROM AUTHOR]