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The Human Leukocyte Antigen (HLA) genes, playing key roles in mediating the immune response, especially HLA class II alleles were suggested to play a role in the activation of autoreactive T-cells in aplastic anemia (AA). Previous studies in different ethnic groups have indicated that some of HLA-A,-B,-DRB1 alleles had a protective or susceptive association with the prevalence, pathogenesis and development of AA. HLA class II genes, especially HLA-DQB1 and -DPB1 alleles or haplotypes at high-resolution level associated with AA have not been fully identified in northern Chinese Han populations. The aim of this study was to identify association of the variations in HLA class II region with AA in northern Chinese Han population. A recent case-control study, including 96 AA patients and 824 healthy controls was performed. The high-resolution HLA genotyping was conducted by PCR-SBT, -SSO and NGS-ION S5TM platform. Based on genotypic data of the three loci, haplotype estimation was carried out. HLA-DRB1*15:01 (Pc = 2.87 × 10-3; OR = 2.11, 95% CI = 1.45–3.07) and HLA-DQB1*06:02 (Pc = 1.86 × 10-2; OR = 2.01, 95% CI = 1.32–3.06) were the risk and predisposition alleles to AA in northern Chinese Han after considering multiple testing. Moreover, the HLA-DRB1*15:01-DQB1*06:02 (Pc = 4.90 × 10-3; OR = 2.09, 95% CI = 1.37–3.19) and HLA-DRB1*14:05-DQB1*05:03 (Pc = 2.65 × 10-2; OR = 2.82, 95%CI = 1.45–5.50) haplotypes had direct strong relevance to AA and were the susceptible haplotypes. HLA-DPB1 alleles and 23 polymorphic amino acid residues spanning exon 2 ~ 4 of DPβ1 molecules have showed no statistically significant associations between AA and controls. The present findings establish a novel link between inherited HLA-DRB1,-DQB1,-DPB1 risk alleles and haplotypes in northern Chinese Han with AA, and open new avenues for development of targeted therapies to prevent or redirect immunopathology in AA.

To determine the water quality status of the primary tributaries in middle and lower reaches of the Yellow River Basin, water collected from the confluence of the ten tributaries and some physical, chemical and biological parameters were analyzed, and then water quality index and health risk were evaluated. Of the ten main tributaries in the middle and lower reaches, only the Qingshui River had water of medium quality in the upper reaches, while all the other tributaries contributed water of poor quality. The Jindi and Dawen rivers in the lower reaches had the poorest water quality, especially the Jindi River. TP, TN, BOD5, COD, TOC and coliform bacteria exceeded the national criteria by 155%, 1%, 97.5%, 35.5%, 114.2%, and 80%, respectively. Cluster analysis indicated that industrial, agricultural, and domestic sewage, along with industrial waste gas, were the main sources of pollution in these tributaries. An analysis of the bacterial community structure showed that the Jindi River was the most polluted and had the largest species diversity and richness of bacteria. Also, its number of pathogenic microorganisms was much higher than that of other areas, and the bacterial functional genes of related metabolic pathways were significantly enriched. This was in sharp contrast with that of the Qingshui River, which had the best water quality. We suggest more specifics policy should be taken for different tributaries, and poor water quality of Jindi and Dawen River should be further studied to explore the most suitable pollution control methods.

Connexin 43 (Cx43) plays an essential role in osteocyte mechanotransduction. Although estrogen involves in the adaptive responses of bone cells to mechanical loadings, its effects on osteocytic Cx43-based gap junction intercellular communication (GJIC) remain obscure. We found that 17β estradiol (E2) up-regulated Cx43, and enhanced GJIC in osteocyte-like MLO-Y4 cells in fluorescence recovery after photobleaching (FRAP) assay. Combination of E2 pre-treatment and oscillating fluid flow (OFF) further enhanced Cx43 expression and mitogen-activated protein kinase (MAPK) phosphorylation, comparing to E2 or OFF treatment alone. Both blocking of classical estrogen receptors (ERα/β) by fulvestrant and ERα knockdown by small interfering RNA inhibited E2-mediated Cx43 increase, while a GPR30-specific agonist G-1 failed to promote Cx43 expression. Our results suggest that the presence of E2 enhanced Cx43-based GJIC mainly via ERα/β pathway, and sensitized osteocytes to mechanical loading.

We report the tunable synthesis and multifunctionalities of Fe 3 O 4 –ZnO hybrid core-shell nanocrystals as prepared through controlled sequential nanoemulsion processes. The characterization shows the orderly variations of the structural, magnetic, photoluminescent and absorption properties of the nanocrystals versus the nanoshell thickness. The nanocrystals reveal structural features unique to the core-shell design and exhibit well-defined superparamagnetic behavior at room temperature. In opposite to the decreasing magnetization, both bandgap and induced surface emissions depend strongly on the increasing nanoshell thickness. Moreover, the FTIR analysis provides the fingerprints of the polymer surfactant, ZnO and Fe 3 O 4 in the same nano-entity and the core-shell nanocrystals could be directly dispersed in both aqueous and organic media for application readiness. Aptly tunable in nanostructures and thus optimized properties, this kind of monosized, high quality, and multifunctional core-shell nanocrystals could be of interest for fundamental studies and potential applications.

We report the one-pot synthesis of bifunctional Au–Fe3O4 hybrid core–shell nanoparticles by controlled sequential reactions. The core–shell nanostructure of the resultant nanoparticles is identified by XRD and TEM, which is further substantiated by the changes in the corresponding physical and chemical properties. The nanoparticles exhibit a well-shaped absorption band in the visible region with a remarkable red-shifting to ∼592 nm and show clear superparamagnetic behavior at room temperature along with enhanced susceptibility, demonstrating the integration of the optical and magnetic functions of the respective components in one entity. This kind of bifunctional optical-magnetic core–shell nanoparticles could be of interest in interfacial proximity effects due to the unique spatial nanostructure configuration and have potential applications in various areas.

Water-dispersible 2 nm FePt ultrasmall nanocrystals coated by a biocompatible triblock copolymer, poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (PEO-PPO-PEO) were directly synthesized in a single-step nanoemulsion process. The FTIR investigation proves the PEO-PPO-PEO molecules on the surface of the resulting nanocrystals, which render the nanocrystals hydrophilic for aqueous dispersion without using conventional ligand exchange and offer proper protection of the nanocrystals from oxidation. The structural and morphological analysis reveals both single-crystallinity and high crystallinity of the nanocrystals in the face-centered cubic phase, with an excellent monosize distribution of 1.95 ± 0.18 nm in diameter. Moreover, the polymer-capped nanocrystals possess well-defined magnetic behavior and the aqueous dispersion–collection process of the nanocrystals was demonstrated for application readiness of such ultrasmall nanocrystals in aqueous media.

Monosized core–shell Fe3O4/Au magnetic–optic multifunctional nanoparticles were synthesized by a modified nanoemulsion process. The formation of the core–shell nanostructure was accomplished in the presence of poly(vinylpyrrolidone) (PVP) as the surfactant in two consecutive steps. The comparison FTIR study proves the PVP coating on the surface of the resultant nanoparticles, whereas the morphological analysis illustrates the nanoparticle shape, nanostructuring, size and size distribution and shows the excellent monodispersity

Magnetite nanocrystals of 2–4 nm were synthesized by a chemical coprecipitation method, by which the particle size was controlled by the reaction temperature. The nanocrystals were investigated by XRD, TEM/HRTEM, VSM and SQUID. It is found that the nanocrystals reveal well-defined superparamagnetic behavior before and after annealing, while the observation of the distinct lattices manifest the high crystallinity of the ultrasmall particles.

We synthesized monodisperse CoPt nanoparticles by a modified polyol process, in which Co(acac)3 and Pt(acac)2 were co-reduced by a diol in the presence of PVP surfactants at high temperature (acac = acetylacetonate, PVP = polyvinylpyrrolidone). It is found that the CoPt nanoparticles assume a face-centered cubic phase and possess high crystallinity, with a particle size of 5.3 nm and a tight size distribution. The nanoparticles show superparamagnetism in the as-synthesized state and become ferromagnetic after annealing. The magnetization process of the nanoparticles prior to heat treatment was analyzed by the Langevin equation and their effective magnetic particle size was thus obtained, in close approximation to the results from the XRD and TEM observation.

Magnetite particles of 2–4 nm were synthesized by an economic, biocompatible chemical coprecipitation route, with their size tuned by the reaction temperature. The microstructure and morphology of the nanoparticles were characterized by X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM), whereas the magnetic properties were investigated by vibrating sample magnetometry (VSM) and superconducting quantum interference device (SQUID). It is found that the nanoparticles demonstrate well-defined superparamagnetic behavior as prepared and after annealing. Distinct lattices were observed which manifest the high crystallinity of such ultrasmall particles and the finite-size effect was revealed by analyzing the corresponding microstructure and magnetism.

Cobalt nanowires were fabricated by DC electrodeposition onto anodic aluminium oxide (AAO) templates. The effects of AAO pore diameter, current density, pH, annealing and deposition under external magnetic fields on the structure and magnetic properties of the nanowire arrays were studied. It is found that the smaller pore size produces high crystallinity, resulting in improved magnetic performance at low current density. The pH can transform fcc-Co phase to hcp-Co phase, with the easy axis along the nanowire axis switched over to the perpendicular direction. Annealing demonstrates excellent thermal stability of the magnetic nanowire arrays at high temperature. The application of external magnetic field during deposition influences the growth habit of the nanowires, leading to the change in the magnetic properties.

Soft-magnetic FeCo alloy nanoparticles with diameters less than 100 nm are prepared by ball milling. X-ray photoemission spectroscopy (XPS) and X-ray magnetic circular dichroism (XMCD) are used to characterize these particles. While the XPS spectrum from the as-prepared sample clearly shows Co photoemission peaks, no sign of Fe is observed in the same spectrum. However, Fe photoemission peaks appear after 1 h of Ar ion sputtering. A quantitative analysis of the XPS spectra shows an increase of Fe concentration versus sputtering time until the Fe:Co ratio of the bulk alloy is reached. In addition, the narrow scan Fe and Co 2p XPS spectra show that Co is more oxidized than Fe. All these measurements indicate that the nanoparticles have a Co shell and an Fe-rich core. They further demonstrate the usefulness of XPS combined with depth-profiling via sputtering to obtain element- and chemically-sensitive structural information on nanoparticles. XMCD as an element-specific magnetic analysis tool further reveals that Fe and Co are ferromagnetically coupled in these particles. The information obtained is useful for establishing a structure–property relation for the studied material that is expected to have applications as a soft magnetic material at high temperatures.

We report the morphology, texture, mechanical properties of Ni films with nanosized grains prepared by electrodeposition as a function of current density. With an increase in current density, the morphology of the nanostructured films was greatly affected and the textures changed from face-centered cubic (1 1 1)- to (2 0 0)-orientation. Consequently, the textural and microstructural alteration exerted strong influence on the hardness of the films, leading to decrease in the hardness (in particular, the inverse Hall–Petch relation) as current density increased, attributed to the distribution of colonies of grain agglomerate and the variation of directional tensile strength.

We have used a simple and direct method to successfully prepare Ag2Se thin films by pulse electrodeposition from a single aqueous solution of Ag and Se ions. The composition analysis confirms the stoichiometry and the morphological characterization shows that the thin films are dense and smooth. The films have the orthorhombic structure of regular Ag2Se materials at room temperature, while the electrical measurements reveal an interesting electrical behavior, similar to that of the Ag2Se nanowire arrays. The Ag2Se thin films were successfully deposited into polymer templates to form well-defined Ag2Se nanostructure, which provides a possibility to apply the method to high density, non-volatile memories based on phase change materials.

Polyvinylpyrrolidone (PVP)-coated sub-5 nm monosize Fe 3 O 4 nanoparticles were synthesized by reduction of Fe(III) acetylacetonate in the presence of PVP polymer as surfactant in one-pot polyol process. Their microstructure and magnetic properties were characterized by XRD, TEM/HRTEM and VSM. It is found that the nanoparticles have high crystallinity with distinct lattices and the magnetic measurements reveal their well-defined superparamagnetic behavior at room temperature. Such Fe 3 O 4 nanoparticles with tailorable size and tunable magnetic properties are promising for biomedical applications.

We have studied the effect of an external magnetic field applied during electrodeposition of Co/Cu barcode nanowires in anodic aluminum oxide nanotemplates. The magnetic properties of the barcode nanowires were greatly enhanced for 50 nm pore diameter regardless of segment aspect ratio, but field deposition has little effect on the 200 nm nanowires. The magnetic improvement is correlated with a structural change, attributed to field modification of the growth habit of the barcode nanowires. A mechanism of growth subject to geometric confinement is proposed.

CoCu thin films were fabricated on a nanocrystalline substrate by DC electrodeposition. It is found that the composition, structure and magnetic properties of the thin films exhibit a strong dependence on the current density and pH values of the bath electrolyte. The effect of annealing as well as the structure–property relation was investigated.