The star formation history (SFH) of galaxies allow us to investigate when galaxies formed their stars and assembled their mass. We can constrain the SFH with high level of precision from galaxies with resolved stellar populations, since we are able to discriminate between stars of different ages from the spectrum they emit. However, the relative importance of secular evolution (nature) over nurture is not yet clear, and separating the effects of interaction-driven evolution in the observed galaxy properties is not trivial. The aim of this study is to use MaNGA (Mapping Nearby Galaxies at APO) Integral Field Unit (IFU) data, in combination with multi-wavelength data, to constrain the SFH of nearby isolated galaxies. We present here the new techniques we are developing to constrain the SFH with high level of precision from Spectral Energy Distribution (SED) fitting. This study is part of a China-Chile collaboration program where we are applying these new techniques to investigate how galaxies formed and evolve in different environments.

Hypoxia is the primary stimulus for the production of erythropoietin (EPO) in both fetal and adult life. Here, we investigated fetal plasma EPO concentrations in monochorionic (MC) twin pregnancies with selective intrauterine growth restriction (sIUGR) and abnormal umbilical artery (UA) Doppler. We diagnosed sIUGR in presence of (1) birth-weight discordance >20% and (2) either twin with a birth weight <10th percentile. An abnormal UA Doppler was defined as a persistent absent-reverse end diastolic flow (AREDF). The intertwin EPO ratio was calculated as the plasma EPO level of the smaller (or small-for-gestational-age) twin divided by the EPO concentration of the larger (or appropriate-for-gestational-age (AGA)) twin. Thirty-two MC twin pairs were included. Of these, 17 pairs were normal twins (Group 1), seven pairs were twins with sIUGR without UA Doppler abnormalities (Group 2), and eight pairs were twins with sIUGR and UA Doppler abnormalities (Group 3). The highest EPO ratio was identified in Group 3 (p < .001) but no significant differences were observed between Groups 1 and 2. Fetal hemoglobin levels did not differ significantly in the three groups, and fetal EPO concentration did not correlate with gestational age at birth. We conclude that fetal plasma EPO concentrations are selectively increased in MC twin pregnancies with sIUGR and abnormal UA Doppler, possibly as a result of uncompensated hypoxia.

The interfacial regimes of cobalt/pentacene/cobalt (Co/Pc/Co) trilayers were emulated through the ultrathin pentacene/cobalt (Pc/Co) and cobalt/pentacene (Co/Pc) bilayers. Employing the magneto-optical Kerr effect (MOKE) measurement, we found the coercivity of Co bottom film in a thickness of 3.4 nm experienced a slight reduction upon the adsorption of Pc molecules. For the bilayers prepared with reversed order of deposition, the Co film deposited on a 6.4 nm Pc layer showed no observable ferromagnetic order at room temperature until its thickness reached 3 nm. After the onset of magnetic order, the x-ray images acquired on Pc/Co revealed a complicated magnetization patterns comparing to those observed on Co/Pc bilayers. Because the spin-polarized carriers will interact with the environment along their transport path, the presence of a non-magnetic layer and the occurrence of complicated domain structures suggested the spin-polarized carriers would experience a greater disturbance on their spin coherence when crossing the Pc/Co interface.

ZnO films were grown on (0001) sapphire substrates by atomic layer deposition (ALD) using diethylzinc (DeZn) and nitrous oxide (N2O) in an inductively heated reactor operated at atmospheric pressure. Low-temperature (LT) ZnO buffer layers having various thicknesses were deposited at 400¢J followed by subsequent growth of ZnO films at 600¢J. Some of the ZnO films were then post-annealed at 1000¢J in the N2O flow. Under certain growth conditions, ZnO nanowires were formed on the post-annealed ZnO samples. Room temperature (RT) photoluminescence (PL) spectra of the ZnO nanowires show strong ultraviolet (UV) near band edge emissions at 3.27 eV with a typical full width at half-maximum ( FWHM ) of ~130 meV and quenched defect luminescence at 2.8 eV. 10 K PL spectra of the post-annealed ZnO all exhibit sharp excitonic emissions with the dominant emission being located at 3.36 eV having a FWHM of 4.6 meV.

A thin-frame nano-network film of titania with backbone diameter of 20–30 nm was obtained from precursor templating of nano-porous polymer with nano-channels 50 nm in width. The nano-porous polymer templates were prepared by selective removal of the polyisoprene (PI) domain with ozone from the bicontinuous structure formed through blending a symmetric polystyrene-block-polyisoprene (PS-b-PI) copolymer with a PS homopolymer (h-PS). The titania network possessed the preferred anatase crystallinity for photocatalytic applications and a specific surface area of 53 m2/g, comparable to that of Degussa P25, a widely used commercial photocatalyst. Photocatalytic performance of the fractured titania network film was also comparable to that of Degussa P25 in both gas-phase NO oxidation and liquid phase methylene blue degradation. The much larger overall structure size of the fractured titania network film, however, offers advantages over the nano-particulate form of P25, namely, easy handling and rapid recycling from treated streams.