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Laser powder bed fusion (L-PBF) additive manufacturing has been used to fabricate complex-shaped structures, which often consist of fine features. Due to transient process phenomena, there are differences in terms of the melt pool formation and the surface morphology depending upon the feature area and scan parameters. This study investigates the scan length effect on the surface morphology and the presence of transient length and width that may have a significant effect as the layer addition continues. For this purpose, four scan lengths (0.25 mm, 0.5 mm, 1.0 mm, and 2.0 mm) are used to fabricate six tracks with back-and-forth scanning. A full factorial design of experiments is used to form multi-track depositions with three levels of power (125 W, 160 W, and 195 W), two levels of scan speed (550 mm/s and 1000 mm/s), and four levels of hatch spacing (80 μm, 100 μm, 120 μm, and 140 μm). A white light interferometer is used to acquire the surface data, and MATLAB is used for surface topographical analysis. The results indicated that the scan length has a significant effect on the surface characteristics. The average height of multi-track deposits increases with the decrease of the scan length. Moreover, the transient length and width can be approximated based on the height variation along both the scan and transverse directions, respectively. 

Graphene layers placed on SrTiO3 single-crystal substrates, i.e., templates for remote epitaxy of functional oxide membranes, were investigated using temperature-dependent confocal Raman spectroscopy. This approach successfully resolved distinct Raman modes of graphene that are often untraceable in conventional measurements with non-confocal optics due to the strong Raman scattering background of SrTiO3. Information on defects and strain states was obtained for a few graphene/SrTiO3 samples that were synthesized by different techniques. This confocal Raman spectroscopic approach can shed light on the investigation of not only this graphene/SrTiO3 system but also various two-dimensional layered materials whose Raman modes interfere with their substrates. 

Inclusive electron scattering cross sections off a hydrogen target at a beam energy of 10.6 GeV have been measured with data collected from the CLAS12 spectrometer at Jefferson Laboratory. These first absolute cross sections from CLAS12 cover a wide kinematic area in invariant mass $W$of the final state hadrons from the pion threshold up to 2.5 GeV for each bin in virtual photon four-momentum transfer squared $Q^2$from 2.55 to $10.4{\mathrm{GeV}}^2$owing to the large scattering angle acceptance of the CLAS12 detector. Comparison of the cross sections with the resonant contributions computed from the CLAS results on the nucleon resonance electroexcitation amplitudes has demonstrated a promising opportunity to extend the information on their $Q^2$evolution up to 10 ${\mathrm{GeV}}^2$. Together these results from CLAS and CLAS12 offer good prospects for probing the nucleon parton distributions at large fractional parton momenta $x$for $W<2.5$GeV, while covering the range of distances where the transition from the strongly coupled to the perturbative regimes is expected. 

In this study, different hatch spacings were used to fabricate single layer and multiple layers, and its effect on porosity was investigated by using microcomputed tomography. The combination of laser power (100 W, 150 W, 175 W, and 195W) and scan speeds (600 mm/s, 800 mm/s, 1000 mm/s and 1200 mm/s) which resulted in the least number of pores were selected from the previous single-track experiment. Six levels of hatch spacings were selected based on the track width to form single and multiple layers: 60%, 70%, 80%, 90%, 120% and 150% of track widths. For the multilayer build, the variation in keyhole porosity within the given window of parameters were found to be attributed to the variation in the hatch spacing. In general, the pore number decreased with increase in hatch spacing from 60% to 90% but increased when hatch spacing further increased from 90% to 120%. 

Transplantation of human embryonic stem cell (hESC)-derived neural progenitors is a potential treatment for neurological disorders, but relatively little is known about the time course for human neuron maturation after transplantation and the emergence of morphological and electrophysiological properties. To address this gap, we transplanted hESC-derived human GABAergic interneuron progenitors into the mouse hippocampus, and then characterized their electrophysiological properties and dendritic arborizations after transplantation by means of ex vivo whole-cell patch clamp recording, followed by biocytin staining, confocal imaging and neuron reconstruction software. We asked whether particular electrophysiological and morphological properties showed maturation-dependent changes after transplantation. We also investigated whether the emergence of particular electrophysiological properties were linked to increased complexity of the dendritic arbors. Human neurons were classified into five distinct neuronal types (Type I-V), ranging from immature to mature fastspiking interneurons. Hierarchical clustering of the dendritic morphology and Sholl analyses suggested four morphologically distinct classes (Class A-D), ranging from simple/immature to highly complex. Incorporating all of our data regardless of neuronal classification, we investigated whether any electrophysiological and morphological features correlated with time post-transplantation. This analysis demonstrated that both dendritic arbors and electrophysiological properties matured after transplantation.