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Electromagnetic waves are widely used in both military and civilian fields, which could cause long-term and high-power exposure to certain populations and may pose a health hazard. The aim of this study was to simulate the long-term and high-power working environment of workers using special electromagnetic radiation occupations to clarify the radiation-induced stress response and cardiac damage and thus gain insights into the mechanisms of injuries caused by electromagnetic radiation. In this study, the combination of microwave and stress was an innovative point, aiming to broaden the research direction with regard to the effect and mechanism of cardiac injury caused by radiation. The myocardial structure was observed by optical and transmission electron microscope, mitochondrial function was detected by flow cytometry, oxidative-stress markers were detected by microplate reader, serum stress hormone was detected by radioimmunoassay, and heart rate variability (HRV) was analyzed by multichannel-physiological recorder. The rats were weighed and subjected to an open field experiment. Western blot (WB) and immunofluorescence (IF) were used to detect the expressions and distributions of JNK (c-Jun N-terminal kinase), p-JNK (phosphorylated c-Jun N-terminal kinase), HSF1 (heat shock factor), and NFATc4 (nuclear factor of activated T-cell 4). This study found that radiation could lead to the disorganization, fragmentation, and dissolution of myocardial fibers, severe mitochondrial cavitation, mitochondrial dysfunction, oxidative-stress injury in myocardium, increase to stress hormone in serum, significant changes in HRV, and a slow gain in weight. The open field experiment indicated that the rats experienced anxiety and depression and had decreased exercise capacity after radiation. The expressions of JNK, p-JNK, HSF1, and NFATc4 in myocardial tissue were all increased. The above results suggested that 30 mW/cm2 of S-band microwave radiation for 35 min could cause both physiological and psychological stress damage in rats; the damage was related to the activation of the JNK pathway, which provided new ideas for research on protection from radiation. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study was to investigate the impact of the co-existence of gestational diabetes (GDM) and hypertension disorders of pregnancy (HDP) on neonatal outcomes in twin pregnancies based on chorionicity. Methods: A retrospective study of 1398 women with twin pregnancies was performed between January 2016 and December 2021. The effects of GDM and HDP on neonatal outcomes were assessed by logistic regression models. An additional stratified analysis was conducted to estimate the effects based on chorionicity (monochorionic (MC) and dichorionic (DC)). Results: The incidence of the co-existence of GDM and HDP was 3.8%. The presence of GDM increased the likelihood of HDP only in women with MC twin pregnancies (OR, 2.13; 95% CI 1.08–4.19). After adjustments, co-existence of GDM and HDP was positively associated with gestational age (β, 1.06; 95% CI 0.43–1.69) and birthweight (β, 174.90; 95% CI 8.91–340.89) in MC twin pregnancies, while no associations were found between co-existence of GDM and HDP and neonatal outcomes in DC twin pregnancies. However, HDP was negatively associated with birthweight (β, −156.97; 95% CI (−257.92, −56.02)) and positively associated with small-for-gestational-age (SGA) (OR, 2.03; 95% CI 1.02–4.03) and discordant twins (OR, 2.83; 95% CI 1.78–4.48) in DC twin pregnant women without GDM. Conclusions: Our results suggested that GDM leads to an increased risk of HDP only in MC twin pregnancies, but GDM seemed to attenuate the adverse effects of HDP on perinatal outcomes in both MC and DC twin pregnancies. Further investigation is needed to explain these intriguing findings. [ABSTRACT FROM AUTHOR]

Two kinds of layered double hydroxides inhibition materials were synthesized on graphene oxide, and applied to strengthen the Ni-based coating on Mg-Li alloy. The composition and release properties of corrosion inhibition materials were studied. The formation of passivated film and the corrosion resistance mechanism of coating were summarized. The results show that two kinds of corrosion inhibition materials had good release properties. The addition of corrosion inhibition materials was helpful to form Ni-based composite coatings with fine and dense cell clusters, which strengthened the corrosion resistance of the coating, especially for a long time. • Two kinds of graphene-based corrosion inhibition materials were synthesized. • Corrosion resistance of Ni-based coatings in different soaking time was studied. • Inhibition materials enhanced the corrosion resistance of coatings on Mg-Li alloy. • Passivation film formation and corrosion resistance mechanism were studied. [ABSTRACT FROM AUTHOR]

Non-invasive optical focusing inside scattering media is still a big challenge because inhomogeneous media scatter incoming photons for focusing and outgoing photons for observation. Various approaches, utilizing non-linear fluorescence or ultrasound, have been reported to address this difficulty. However, implementation of these methods is complicated and highly expensive, as ultrafast laser systems or photo-acoustic equipment must be employed. Here, we demonstrate a wavefront shaping technique to achieve non-invasive focusing inside scattering media using only a linear fluorescent signal. The contrast and mean of incoherent speckles, produced by the linear fluorescence, are utilized as feedback signals to optimize the input wavefront. While increasing speckle contrast makes the focus tighter and increasing the speckle mean enhances the intensity, fine-tuning the contribution of these two factors in our two-step optimization is essential. An optimal wavefront is found to achieve simultaneously both a micrometer focal spot size (down to 20 μm diameter) and high intensity (more than a 100-fold enhancement) inside the scattering media. Our method promises a route in life science toward focusing, imaging, or manipulating deep into biological tissues with linear fluorescent agents. [ABSTRACT FROM AUTHOR]

For the application of lightweight alloys, the corrosion and wear problems of magnesium-lithium (Mg-Li) alloys have always been important problems that cannot be ignored. The coupling protection of multiple technologies has gradually become a new trend. In this study, layered double hydroxides (LDH) nanosheet arrays were in-situ grown on Ni-P coating by the electroless plating technology combined with hydrothermal synthesis technology. The optimum deposition conditions (temperature-time-pH) were selected by orthogonal test. The surface morphology, structure, corrosion resistance and wear resistance of LDH/Ni composite coatings under different conditions were systematically studied by SEM, XRD, FT-IR, DSC, electrochemical and tribological tests. The growth mechanism of LDH suitable for Ni-P coating surface was proposed by analyzing the growth process of LDH nanosheet arrays. The results showed that the condition of 125 °C-12 h-13 was conducive to the growth of LDH nanosheet arrays. Compared with the Ni-P coating and the composite coating under other conditions, the LDH 125°C-12h-13 /Ni composite coating has the lowest self-etching current density (7.50 × 10−7 A·cm−2) and the average friction coefficient (0.35). The defect sealing effect and Cl− barrier property of LDH effectively improved the corrosion resistance of the coating. The frictional properties were improved by lubrication and heat absorption properties of LDH. In addition, it was found that the growth of LDH on the Ni-P coating surface followed the mechanism of "deposition nucleation-diffusion growth". • Nanosheet arrays in-situ coupled Ni-based coatings on Mg-Li alloy were prepared. • Optimum growth conditions of nanosheet arrays were selected by orthogonal test. • The composite coating had better corrosion and wear resistance for Mg-Li alloy. • Wear mechanism and growth mechanism of LDH nanosheet arrays were studied. [ABSTRACT FROM AUTHOR]

As a lightweight material, the wide application of Mg-Li alloy is restricted by its corrosion resistance. Focusing on this, an innovative superhydrophobic composite coatings of nickel-based metal coupled with layered double hydroxides (LDHs) was prepared on Mg-Li alloy. The microstructure, hydrophobic property and corrosion resistance of coatings were investigated by SEM, TEM, XRD, FT-IR, AFM, contact angle tester and electrochemical test. The results indicated that the MgAl LDHs uniformly grown in situ on the NiP coating deposited on Mg-Li alloy through electroless plating and hydrothermal treatment. The MgAl LDHs with a complex honeycomb micro-nano structure improved the surface roughness of the composite coating to 126 nm. The two-step treatment achieved an excellent coupling between the metal-based coating and inorganic compounds. The low surface energy treatment of micro-nano structure on NiP coating surface with stearic acid (@SA) realized the superhydrophobic transition of the composite coating (WAC=154.27° ± 2.56°). Besides, MgAl LDHs showed better trapping properties for Cl-. Under the synergistic effect of anion capture and hydrophobic effect, the corrosion current density (1.35 ×10−7 A⋅cm−2) and impedance modulus of NiP/MgAl LDHs@SA coating were significantly better than those of NiP and NiP/MgAl LDHs coating. The superhydrophobic composite coating provided a better anticorrosion choice for Mg-Li alloy. [Display omitted] • A new superhydrophobic double-layer coatings were prepared on the Mg-Li alloy. • MgAl LDHs with uniform honeycomb structure were in situ grown on the NiP coating. • Modified by stearic acid, the double-layer coatings had good superhydrophobicity. • The superhydrophobic double-layer coatings showed excellent corrosion resistance. [ABSTRACT FROM AUTHOR]

Summary Regeneration in many organisms involves the formation of a blastema, which differentiates and organizes into the appropriate missing tissues. How blastema pattern is generated and integrated with pre-existing tissues is a central question in the field of regeneration. Planarians are free-living flatworms capable of rapidly regenerating from small body fragments [ 1 ]. A cell cluster at the anterior tip of planarian head blastemas (the anterior pole) is required for anterior-posterior (AP) and medial-lateral (ML) blastema patterning [ 2–4 ]. Transplantation of the head tip into tails induced host tissues to grow patterned head-like outgrowths containing a midline. Given the important patterning role of the anterior pole, understanding how it becomes localized during regeneration would help explain how wounds establish pattern in new tissue. Anterior pole progenitors were specified at the pre-existing midline of regenerating fragments, even when this location deviated from the ML median plane of the wound face. Anterior pole progenitors were specified broadly on the dorsal-ventral (DV) axis and subsequently formed a cluster at the DV boundary of the animal. We propose that three landmarks of pre-existing tissue at wounds set the location of anterior pole formation: a polarized AP axis, the pre-existing midline, and the dorsal-ventral median plane. Subsequently, blastema pattern is organized around the anterior pole. This process, utilizing positional information in existing tissue at unpredictably shaped wounds, can influence the patterning of new tissue in a manner that facilitates integration with pre-existing tissue in regeneration. [ABSTRACT FROM AUTHOR]

• Fluorescence imaging through a thin scattering media using speckle deconvolution. • No PSF pre-characterization is required with dual-color fluorescence, which enables speckle deconvolution in relatively simple and non-invasive manner. • Extending the depth-of-field of scattering imaging system by PSF manipulation. Over the last decade, many methods have been proposed to achieve optical imaging through scattering media. Among them, speckle deconvolution utilizing the optical memory effect of the medium is widely employed due to its advantages in imaging speed and relatively simpler setup. However, practical applications of speckle deconvolution method are rarely demonstrated as most of the existing systems are based on transmission geometry to ensure direct incoherent illumination and easy detection. Here we propose an imaging system in reflection configuration that is able to retrieve the hidden fluorescent object behind a thin scattering media by speckle deconvolution. The object speckle pattern and speckle pattern from a point source (point spread function of the system, PSF) are spectrally separated to facilitate non-invasive image acquisitions. It is shown that, to reconstruct object faithfully, spectral de-correlation and chromatic aberration induced depth de-correlation between the object speckle pattern and the PSF have to be compensated. Speckle correlation is employed to characterize the depth-of-field (DOF) range in this reflection imaging system. Within the DOF, focus and defocus effects in the reconstructed objects are observed when rescaling the PSF onto different axial planes. Beyond the DOF, hidden objects that originally fail in reconstruction can be retrieved by PSF stacking and PSF rescaling. The proposed approach is potentially to find wide applications in biomedical imaging, ranging from deep tissue fluorescence microscopy to small animal imaging. [ABSTRACT FROM AUTHOR]

[Display omitted] • CeO 2 nanoparticles modified GO composites were synthesized by hydrothermal method. • Electroless Ni-P coatings enhanced by modified GO were prepared on Mg-Li alloys. • The microstructure of coatings became uniform and dense after adding modified GO. • Adding modified GO was conducive to improving the wear resistance of coatings. • Modified GO significantly improved the corrosion resistance of coatings. A new strategy of CeO 2 nanoparticles integration with GO nanosheets (CeO 2 @GO composites) was adopted for reinforcing Ni-P coating on Mg-Li alloys. Besides, the effect of GO nanosheets and CeO 2 @GO composites as reinforced particles on the microstructure, corrosion resistance and wear resistance of Ni-P coating were investigated. CeO 2 nanoparticles with average size of 4.19 nm were uniformly synthesized on GO nanosheets by hydrothermal method. The cellular nodules of coatings were refined after adding GO nanosheets and CeO 2 @GO composites. Moreover, the compactness and flatness of CeO 2 @GO-Ni-P composite coating were better than that of GO-Ni-P composite coating. The average friction coefficient of CeO 2 @GO-Ni-P composite coating (0.331) was decreased by 17%, 35.5%, and 39.6% than that of GO-Ni-P composite coating, Ni-P coating and Mg-Li substrate, respectively. The addition of GO nanosheets and CeO 2 @GO composites both improved the corrosion resistance of coatings, while CeO 2 @GO-Ni-P composite coating has the best corrosion resistance. Compared with Mg-Li alloys, the self-corrosion potential of CeO 2 @GO-Ni-P composite coating (-0.35 ± 0.006 V) shifted to positive potential by 1.28 V, and the self-corrosion current density was reduced by two order of magnitude (1.41 ± 0.13 × 10-6 A⋅cm−2). This was mainly attributed to the synergistic effect of the CeO 2 nanoparticles on the GO nanosheets. [ABSTRACT FROM AUTHOR]

The heart is one of the major organs affected by microwave radiation, and these effects have been extensively studied. Previous studies have shown that microwave-radiation-induced heart injury might be related to the abnormal expression and distribution of Cx43. In order to make the research model closer to humans, we used iPSC-CMs as the cell injury model to investigate the biological effect and mechanism of iPSC-CM injury after microwave radiation. To model the damage, iPSC-CMs were separated into four groups and exposed to single or composite S-band (2.856 GHz) and X-band (9.375 GHz) microwave radiation sources with an average power density of 30 mW/cm2. After that, FCM was used to detect cell activity, and ELISA was used to detect the contents of myocardial enzymes and injury markers in the culture medium, and it was discovered that cell activity decreased and the contents increased after radiation. TEM and SEM showed that the ultrastructure of the cell membrane, mitochondria, and ID was damaged. Mitochondrial function was aberrant, and glycolytic capacity decreased after exposure. The electrical conduction function of iPSC-CM was abnormal; the conduction velocity was decreased, and the pulsation amplitude was reduced. Wb, qRT-PCR, and IF detections showed that the expression of Cx43 was decreased and the distribution of Cx43 at the gap junction was disordered. Single or composite exposure to S- and X-band microwave radiation caused damage to the structure and function of iPSC-CMs, primarily affecting the cell membrane, mitochondria, and ID. The composite exposure group was more severely harmed than the single exposure group. These abnormalities in structure and function were related to the decreased expression and disordered distribution of Cx43. [ABSTRACT FROM AUTHOR]

In this study, graphite/CeO 2 reinforced Co-based coatings were prepared on the surface of HT250 gray cast iron by the plasma cladding technology. The influence of graphite and CeO 2 on microstructure and properties of Co-based coatings were studied in detail. The phase composition and microstructure of coatings were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The micro-hardness, wear resistance and corrosion resistance of coatings were evaluated using micro-hardness tester, friction wear testing machine and electrochemical workstation. The results showed that the addition of graphite was beneficial to enhance micro-hardness and wear resistance of coatings, but there was still shortcoming in improving corrosion resistance. On this basis, CeO 2 was further introduced together with graphite. The microstructure of coatings was found to be more uniform under the synergy of graphite and CeO 2. The micro-hardness increased from 684.5 HV 0.3 (coatings adding graphite alone) to 767.4 HV 0.3 (coatings adding graphite and CeO 2), which was 29.7% and 115.1% higher than that of as-cladded coatings and substrate respectively. More importantly, the corrosion current density of coatings was an order of magnitude lower than that of coatings adding graphite alone. Therefore, adding CeO 2 together with graphite was beneficial to the synergistic improvement of micro-hardness, wear resistance and corrosion resistance of Co-based coatings. • Co-based coatings adding graphite/CeO 2 were prepared by plasma cladding. • The microstructure of coatings became uniform after adding graphite/CeO 2. • Wear resistance of coatings adding graphite together with CeO 2 was enhanced. • Corrosion resistance of coatings adding graphite together with CeO 2 was raised. [ABSTRACT FROM AUTHOR]

A 62-year-old woman receiving R-CHOP chemotherapy for extranodal lymphoma had diffuse, symmetric patches and soft, thin plaques of retiform purpura on her extremities and acral surfaces. Results of physical examination and laboratory testing, including fibrinogen level and coagulation panel, were unremarkable except for leukocytosis, thrombocytopenia, and low hemoglobin count and hematocrit. What is the diagnosis and what would you do next? [ABSTRACT FROM AUTHOR]

• High quality Ni-coated graphene powders were prepared by electroless plating. • Modified graphene was preserved in laser cladded coatings. • Modified graphene was conducive to improving the wear resistance of coatings. • Modified graphene significantly improved the corrosion resistance of coatings. In recent years, graphene (Gr) has attracted much attention owing to its excellent reinforcement effects. However, the application of Gr in laser cladded coatings remains a challenge due to the agglomeration of Gr and poor wettability between Gr and the molten metals. To overcome these problems, in this study, Ni modified Gr (Ni@Gr) powders were synthesized by electroless plating method, and Ni@Gr powders reinforced Ni60 (Ni60-Ni@Gr) composite coatings were prepared on the surface of AISI 1045 steel by laser cladding technique. The microstructure, existential state of Gr nanosheets, micro-hardness, wear resistance and corrosion resistance of Ni60-Ni@Gr coatings, Ni60-Gr coatings and Ni60 coatings were studied by SEM, TEM, XRD, Raman, micro-hardness tester, wear tester and electrochemical tester. The results showed that the wettability between the metal matrix and Gr was improved after modification, which promotes the dispersion of Gr nanosheets. The average micro-hardness value of Ni60-Ni@Gr coating was 920.79 HV 0.2 , which was higher than that of Ni60-Gr coatings (843.80 HV 0.2) and Ni60 coatings (777.13 HV 0.2). Compared with Ni60-Gr coatings and Ni60 coatings, the Ni60-Ni@Gr coatings have the lowest friction coefficient and weight loss, indicating the best wear resistance of Ni60-Ni@Gr coatings. The potentiodynamic polarization test and EIS test indicated that the corrosion resistance of Ni60 coatings was significantly improved after adding Gr. More notably, compared with the Gr without modification, the addition of modified Gr contributes to the further improvement of the corrosion resistance of Ni60 coating, which was related to the excellent barrier property of uniformly dispersed Ni@Gr powders in coatings. [ABSTRACT FROM AUTHOR]

An ablation resistant coating with self-transpiration cooling effect was prepared on the surface of aluminum alloy by dilution effect of high speed laser cladding. The coatings mainly contain ablation resistant phases ZrB 2 and SiC, and low-melting phases Al and Al 3.21 Si 0.47. The ablation property of coatings was investigated at different heat fluxes (35.39, 70.77, 106.16, 141.54) MW⸱m−2. The mass ablation rate increased gradually, and the morphology of ablation region changed significantly with the increased heat flux. The self-transpiration cooling effect of coatings was studied by phase, morphology, and element distribution of ablation region. The self-transpiration cooling effect weakened the oxidation behavior of ZrB 2 and SiC at heat fluxes of 35.39 and 70.77 MW⸱m−2 and protected the coating from being exhausted when the heat fluxes were 106.16 and 141.54 MW⸱m−2. [ABSTRACT FROM AUTHOR]

Access to both the phase and intensity of an image can be provided using digital holographic (DH) imaging techniques. Recently, the difference of two holograms captured with two appropriately related wavelengths was demonstrated to produce the Laplacian of an object field. Applying telecommunication lasers the feasibility of infrared (IR) DH and DH Laplacian reconstruction and the associated theoretical analyses are presented. This is achieved by combining a tunable mid-IR laser source and mid-IR sensitive InGaAs-based digital camera. [ABSTRACT FROM AUTHOR]

The quadratic minimum spanning tree problem (QMSTP) is a spanning tree optimization problem that considers the interaction cost between pairs of edges arising from a number of practical scenarios. This problem is NP-hard, and therefore there is not a known polynomial time approach to solve it. To find a close-to-optimal solution to the problem in a reasonable time, we present for the first time a clustering-enhanced memetic algorithm (CMA) that combines four components, i.e., (i) population initialization with clustering mechanism, (ii) a tabu-based nearby exploration phase to search nearby local optima in a restricted area, (iii) a three-parent combination operator to generate promising offspring solutions, and (iv) a mutation operator using Lévy distribution to prevent the population from premature. Computational experiments are carried on 36 benchmark instances from 3 standard sets, and the results show that the proposed algorithm is competitive with the state-of-the-art approaches. In particular, it reports improved upper bounds for the 25 most challenging instances with unproven optimal solutions, while matching the best-known results for all but 2 of the remaining instances. Additional analysis highlights the contribution of the clustering mechanism and combination operator to the performance of the algorithm. [ABSTRACT FROM AUTHOR]

In this work, the fabrication of supersonic fine particle bombardment (SFPB)-doped rare-earth pretreatment modified vacuum carburized layers were applied. The SFPB-doped La 2 O 3 pretreated vacuum carburized reinforced layer was explored by common testing methods such as XRD, XPS, SEM, and TEM, focusing on the effects of La 2 O 3 -doped SFPB pretreatment on the decomposition, adsorption and diffusion of active carbon atoms and the diffusion mechanism. The composite carburizing behavior of La 2 O 3 -doped SFPB pretreatment modified layer under the action of thermal coupling is explored, and the influence law of rare earth modified carburizing and nano-modified carburizing on the thickness, residual stress, impact toughness, tribological properties of the carburized layer were clarified. The mechanism of mass transfer under the coupling role of pre-set surface defects and rare earth pinning was revealed. The case depth of the LSPC layer was increased by 14.3%, and the residual stress was significantly higher. The carbon diffusion coefficients of LSPC were 1.31 times superior to that of the vacuum carburizing layer, which is mainly attributed to the formation of a large number of nanocrystals with high-angle grain boundaries (HAGBs) by the rare-earth doped nanosized pretreatment, and the multiple synergistic strengthening effects of rare-earth oxides and nanocrystals. [Display omitted] • SFPB pretreatment introduces both La 2 O 3 and diffusion channels into the surface/subsurface layer. • Enhancement of carbon diffusion driving force by La 2 O 3. • High dislocation density and LAGBs provide fast diffusion channels for carbon diffusion. • The pretreatment increased the thickness of the carburized layer by 14.3%. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) as nano reinforcement has been extensively used to improve the overall performance of metal-based composite coatings. In this work, GO nanosheets with surface modification and magnetic field (MF) assisted electro-brush plating (EBP) technique were employed to construct Ni-based composite coatings with biomimetic structure to improve the corrosion resistance of coatings. The preparation, deposited behavior and some properties of coatings were investigated. The results showed that after surface modification, GO surface carried numerous Co 7 Fe 3 magnetic nanoparticles with the size of 40–50 nm. During the MF assisted EBP process, the co-deposition of CoFe@GO magnetic powders with the reduced Ni atoms contributed to the formation of Ni-CoFe@GO composite coatings with stripe-like structure that resembled the surface morphology of conch. Besides, induced by the synergistic action of MF and electric field, most magnetic powders were distributed regularly in the stripe-like areas. After two weeks exposure to air, Ni-CoFe@GO composite coatings changed spontaneously from hydrophilic for fresh coatings to hydrophobic. This transformation was mainly attributed to the high surface roughness and the adsorption of a lot of hydrocarbons on the stripe-like surface. Moreover, air pockets that resulted from these hydrocarbons formed on the coating surface impeded the diffusion of corrosive media into coatings. Consequently, Ni-CoFe@GO composite coatings exhibited good corrosion resistance. Therefore, the preparation proposed in this work is desirable and has a prospect in further improving the corrosion resistance of GO reinforced Ni-based composite coatings. • A composite method was employed to prepare a new GO-reinforced Ni-based coating. • This coating presented the stripe-like structure similar to conch surface. • GO changed from non-magnetic to magnetic via surface modification. • Ni-CoFe@GO coatings exhibited hydrophobicity and good corrosion resistance. [ABSTRACT FROM AUTHOR]

As reinforcements, carbonaceous nanomaterials (CNMs) especially multi-walled carbon nanotubes (MWCNTs) and graphene oxide (GO), have attracted increasing attention in the application of electrodeposition. In this work, Ni-based nanocomposite coatings with MWCNTs and GO were prepared by electro-brush plating technique (EBP). The results showed that adding MWCNTs and adding GO both significantly improved the compactness of Ni coatings, however, the latter contributed more uniform microstructure and morphology of nanocomposite coatings owing to the excellent dispersion of GO. In addition, MWCNTs and GO could not only provide numerous nucleation sites for Ni primary crystals contributing the grain refinement, but also co-deposited with Ni atoms to form a strong interfacial bonding with Ni matrix. The addition of MWCNTs and GO can significantly reduce the worn volume of coatings from 7.52 × 107 μm3 to 3.49 × 107 μm3 and 2.82 × 107 μm3, respectively. Moreover, Ni nanocomposite coatings adding GO exhibited better wear resistance and friction stability than that of adding MWCNTs. Microstructural characterizations revealed that during wear testing, the agglomerated MWCNTs in nanocomposite coatings were destroyed severely and transformed into the shorten MWCNTs or the unfolded sidewalls, thereby leading to the instability of the wear process. In contrast, the damage degree of rGO was relatively slight. The nanosheets of rGO uniformly distributed in nanocomposite coatings became smaller and some of them were stacked between each other, which promoted the stability of friction process. Image 1 • Comparison study of MWCNTs and GO reinforced Ni composite coatings was conducted. • Both MWCNTs and GO significantly improved the compactness of pure Ni coatings. • HRTEM characterization provided evidences for grain refinement of MWCNTs and GO. • Adding GO promoted the stability of friction process compared with MWCNTs. • Structural variations of MWCNTs and GO after wear testing were investigated. [ABSTRACT FROM AUTHOR]

The article offers information on role of muscle and neuronal guidepost-like cells in regeneration of the planarian visual system. Topics discussed include association of regeneration of the visual system with axonal projections; array of signaling cues, which provide positional information essential for planarian patterning; and identification of molecules and transcription factors expressed in these cells.