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The increasing population of diabetes mellitus in adolescent girls and women of childbearing age contributes to a large number of pregnancies with maternal pregestational diabetes mellitus. Congenital heart diseases are a common adverse outcome in mothers with pregestational diabetes mellitus. However, there is little systematic information between maternal pregestational diabetes mellitus and congenital heart diseases in the offspring.Literature selection was performed in PubMed. One hundred and seven papers were cited in our review, including 36 clinical studies, 26 experimental studies, 31 reviews, eight meta-analysis articles, and six of other types.Maternal pregestational diabetes mellitus poses a high risk of congenital heart diseases in the offspring and causes variety of phenotypes of congenital heart diseases. Factors such as persistent maternal hyperglycemia, oxidative stress, polymorphism of uncoupling protein 2, polymorphism of adiponectin gene, Notch 1 pathway, Nkx2.5 disorders, dysregulation of the hypoxia-inducible factor 1, and viral etiologies are associated with the occurrence of congenital heart diseases in the offspring of mothers with pregestational diabetes mellitus. Treatment options including blood sugar-reducing, anti-oxidative stress drug supplements and exercise can help to prevent maternal pregestational diabetes mellitus from inducing congenital heart diseases.Our review contributes to a better understanding of the association between maternal pregestational diabetes mellitus and congenital heart diseases in the offspring and to a profound thought of the mechanism, preventive and therapeutic measurements of congenital heart diseases caused by maternal pregestational diabetes mellitus.

Bioactive porous surface on metal implants are benefit for forming the continuous interface with “mechanical interlocking” and “chemical bonding” between implants and bones. In the present study, the main attention was concentrated on fabricating a porous bioactive surface on Ti substrate. Porous surface was first fabricated by two-step etched. Then thin HA coating was deposited on the pre-treated porous Ti surface by sol-gel method and immediately sintered at 500°C for 1 hour. The structure and morphology of HA coating formed on the porous surface were characterized by thin-film X-ray diffrac- tion and scanning electronic microscopy, respectively. Rietveld method and Warren-Averbach Fourier Transfer Analysis were employed to determine the lattice parameters, crystallite size and micro-strain of HA coating. The SEM results indicated that an interconnecting porous surface with cancellous structure and mean diameter about 1/m was etched on the Ti substrate, and the surface was covered by a thin particle coating. The TF-XRD results testified that the thin coating was poor crystalline HA.

Dissolution of mechanically activated Panzhihua ilmenite was conducted in 5–20% sulphuric acid solutions. With high milling intensity the milling atmosphere significantly affected the dissolution with milling under vacuum almost double the dissolution of ilmenite milled in air. This was due to formation of a lot of acid-resistant pseudorutile and lowering level of the lattice strains, especially in the c-axis direction of the ilmenite unit cell, upon milling in air. Under the experimental conditions applied, titanium and iron dissolved at a nearly stoichiometric ratio. Hydrolysis of the dissolved titanium, however, was also in progress simultaneously. The sulphuric acid concentration and reaction temperature remarkably influenced the hydrolysis rate, thus affecting the microstructure of the hydrolysate. In 5 wt.% and 10 wt.% acid solutions, the hydrolyzed product was poorly compacted and dissolution could continue. In contrast, the product in 20 wt.% acid exhibited a compact structure and was strongly adherent preventing further dissolution of the un-reacted ilmenite. In both cases the hydrolysis product appeared to be rutile TiO2. The experimental results showed that significant hydrolysis was inevitable when the acid concentration was ≤ 20 wt.%. Therefore, preparation of synthetic rutile from mechanically activated ilmenite is a better alternative to direct production of pigment TiO2. And the method could directly and fully reuse the spent acid discharged in the sulphate process.

Structure parameters of minerals in human bone, bioapatite, are very important for biomaterials. In situ micro-XRD and Rietveld structure refinement were used to extract subtle structure information of human ribs. Rietveld refinement testified that lattice parameters, crystallite size and microstrain for cortical and cancellous bones were significant difference. Anisotropic crystallite sizes of human rib showed preferential growth of apatite along c-axis and the graded variation at radial direction of bone axis. The variations of the subtle structures of bioapatite, such as, P occupancy and P-O2 bond length, as well as distortion index of P-O tetrahedron, demonstrated the tendency of mineralization and the content of CO3 2- in human ribs.

Calcium-deficient hydroxylapatite (CDHA) powders with Ca/P ratios from1.5 to 1.67 were synthesized by wet-chemical method. Rietveld structure refinement was performed on the X-ray diffraction data and Fourier transform infrared spectroscopy was used to characterize molecular and crystal structure of CDHA. With the decrease of Ca/P ratio, the crystallite size and crystallinity decreased, but the acid phosphate content and amount of vacancies in hydroxyapatite hexagonal structure increased. The disorder of CDHA structure increase indicated calcium-deficiency and HPO4 replacement resulted in disorder of crystal in apatite structure. The more calcium is deficient, the more disorder or imperfect in CDHA structure

Dissolution of mechanically activated Panzhihua ilmenite was carried out at 100 °C with a 50% sulfuric acid solution. The particle size, specific surface area, crystallite size, lattice strain and mechano-chemical reaction of milled ilmenite were measured. The cleavage induced by energetic milling occurred more preferentially along the a -axis of ilmenite unit cell. It was found that the defects formed in milling process, especially the lattice strain in the c -axis of ilmenite unit cell, greatly enhanced the leaching reaction. At low temperatures, the leaching reaction is likely to start along the direction of the basal plane (0 0 0 1) of milled ilmenite. With the mechanically activated ilmenite, leaching conversion at 100 °C reached 82.1%. However, the leaching kinetic tests revealed that the ball milling only partially activated the ilmenite. The initial rapid dissolution is due to the leaching of both the fine powders and highly reactive crystal faces. In the later stage, the dissolution exhibited essentially the same behavior as non-activated ilmenite.

The effect of 975 W microwave irradiation on the crystalline structure of isotactic polypropylene (iPP) surface layer in Al/iPP/Al composite was studied by attenuated total reflection Fourier transform infrared (FTIR) and asymmetry diffraction geometry small-angle x-ray diffraction (XRD). The results show that after about 60 min irradiation, the orientated structure and crystallinity of the iPP surface layer are dropped, crystal transformation (α → β) happens. The iterative peak-fit of XRD curves indicates that the reasons for crystal transformations are: the microwave effect causes the increase of the order level of the crystal lattice, the defaults within the β-crystals are, thus, reduced. D [300] (stands for β-form phase) becomes larger, β-form iPP becomes more perfect. With microscopic distortion coefficient e [300] and the microscopic stress of β-form becomes less attraction, the microscopic stress of the α-form goes up. This crystal transformation is useful for improving the toughness of iP...

The residual stress of the iPP surface layer in Al/iPP/Al under the influence of microwave irradiation was investigated by thin film (TF)-X-ray diffraction (XRD). Depending on the irradiation time, we calculated the macro residual stress, micro stress, and lattice static distortion stress. The results show that the macroscopic residual tensile stress of irradiated iPP samples dropped from about 12 MPa to 4 MPa. D(300) (the β crystal phase) becomes larger from about 4 to 10 nm as the irradiation time increased, and the β-form iPP becomes more perfect. However, for theα-form phase, D(110) remains almost stable. Moreover, the microscopic distortion coefficient e(300) that decreases from approximately 0.03 to 0.018, becomes smaller than e(110) parallel to the irradiation time, so the microscopic stress of the β-crystal is decreased. In addition, the lattice static distortion energy of the α-form greatly increases from 2 to 6 MPa, but the lattice static distortion energy of the β-crystals remains constant at about 1.5 MPa and is much smaller than that of the α-crystals at the same irradiation time. These calculated results are in good agreement with that of the crystallinity and order parameter of the β-crystals of the TF-XRD. The lattice distortion energy is a major portion of the plastic deformation, therefore, it suggests that the lattice static distortion energy is the main cause of α β crystalline transformation. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3759–3765, 2004