This paper is the first to study the effect of financial restatement on bank loan contracting. Compared with loans initiated before restatement, loans initiated after restatement have significantly higher spreads, shorter maturities, higher likelihood of being secured, and more covenant restrictions. The increase in loan spread is significantly larger for fraudulent restating firms than other restating firms. We also find that after restatement, the number of lenders per loan declines and firms pay higher upfront and annual fees. These results are consistent with the view that banks use tighter loan contract terms to overcome risk and information problems arising from financial restatements.

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Chiral self-assembled nanomaterials with biological applications have attracted great interest. In this study, DNA-driven gold-upconversion nanoparticle (Au-UCNP) pyramids were fabricated to detect intracellular microRNA (miRNA) in real time. The Au-UCNP pyramids are doubly optically active, displaying strong plasmonic circular dichroism (CD) at 521 nm and significant luminescence in 500-600 nm, and therefore can be monitored by both of them. CD will decrease while the luminescence intensity increases in the presence of miRNA. The experimental results show that the CD intensity had an outstanding linear range from 0.073 to 43.65 fmol/10 μg(RNA) and a limit of detection (LOD) of 0.03 fmol/10 μg(RNA), whereas the luminescence intensity ranged from 0.16 to 43.65 fmol/10 μg(RNA) with a LOD of 0.12 fmol/10 μg(RNA). These data indicate that the CD signal is much more sensitive to the concentration of miRNA than the luminescent signal, which is attributed to the strong CD intensity arising from the spin angular momentum of the photon interaction with chiral nanostructures and the plasmonic enhancement of the intrinsic chirality of DNA molecules in the pyramids. This approach opens up a new avenue to the ultrasensitive detection and quantification of miRNA in living cells.

We study the role of manager-specific heterogeneity in explaining executive compensation. We decompose the variation in executive compensation into time variant and invariant firm and manager components and find that time invariant manager fixed effects explain a majority of the variation in executive pay. In addition, we show that including manager fixed effects alters coefficients and interpretations of other variables. We also find that firm performance improves after CEOs with larger compensation fixed effects are hired, which is consistent with the fixed effect being associated with innate managerial ability or social capital, which in turn leads to better performance. We further derive managers' excess compensation by purging time variant effects and firm, manager, and year fixed effects, and show that firms with over-paid managers use less debt, consistent with theoretical predictions.JEL Classification: G3, G32, J24, J31, J33, C23 Keywords: Executive compensation, CEO pay, latent managerial ability, human capital, fixed effects, manager fixed effects, capital structure Managerial Attributes and Executive Compensation AbstractWe study the role of manager-specific heterogeneity in explaining executive compensation. We decompose the variation in executive compensation into time variant and invariant firm and manager components and find that time invariant manager fixed effects explain a majority of the variation in executive pay. In addition, we show that including manager fixed effects alters coefficients and interpretations of other variables. We also find that firm performance improves after CEOs with larger compensation fixed effects are hired, which is consistent with the fixed effect being associated with innate managerial ability or social capital, which in turn leads to better performance. We further derive managers' excess compensation by purging time variant effects and firm, manager, and year fixed effects, and show that firms with over-paid managers use less debt, consistent with theoretical predictions.JEL Classification: G3, G32, J24, J31, J33, C23

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We theoretically study the three-dimensional topological semimetals with nodal surfaces protected by crystalline symmetries. Different from the well-known nodal-point and nodal-line semimetals, in these materials, the conduction and valence bands cross on closed nodal surfaces in the Brillouin zone. We propose different classes of nodal surfaces, both in the absence and in the presence of spinorbit coupling (SOC). In the absence of SOC, a class of nodal surfaces can be protected by spacetime inversion symmetry and sublattice symmetry and characterized by a Z2 index, while another class of nodal surfaces are guaranteed by a combination of nonsymmorphic two-fold screw-rotational symmetry and time-reversal symmetry. We show that the inclusion of SOC will destroy the former class of nodal surfaces but may preserve the latter provided that the inversion symmetry is broken. We further generalize the result to magnetically ordered systems and show that protected nodal surfaces can also exist in magnetic materials without and with SOC, given that certain magnetic group symmetry requirements are satisfied. Several concrete nodal-surface material examples are predicted via the first-principles calculations. The possibility of multi-nodal-surface materials is discussed.arXiv:1712.09773v2 [cond-mat.mes-hall]

Despite favorable responses of chimeric antigen receptor (CAR)-engineered T-cell therapy in patients with hematologic malignancies, the outcome has been far from satisfactory in the treatment of solid tumors, partially owing to the development of an immunosuppressive tumor microenvironment. To overcome this limitation, we engineered CAR T cells secreting checkpoint inhibitors (CPI) targeting PD-1 (CAR.αPD1-T) and evaluated their efficacy in a human lung carcinoma xenograft mouse model. To evaluate the effector function and expansion capacity of CAR.αPD1-T cells , we measured the production of IFNγ and T-cell proliferation following antigen-specific stimulation. Furthermore, the antitumor efficacy of CAR.αPD1-T cells, CAR T cells, and CAR T cells combined with anti-PD-1 antibody was determined using a xenograft mouse model. Finally, the underlying mechanism was investigated by analyzing the expansion and functional capacity of TILs. Human anti-PD-1 CPIs secreted by CAR.αPD1-T cells efficiently bound to PD-1 and reversed the inhibitory effect of PD-1/PD-L1 interaction on T-cell function. PD-1 blockade by continuously secreted anti-PD-1 attenuated the inhibitory T-cell signaling and enhanced T-cell expansion and effector function both and In the xenograft mouse model, we demonstrated that the secretion of anti-PD-1 enhanced the antitumor activity of CAR T cells and prolonged overall survival. With constitutive anti-PD-1 secretion, CAR.αPD1-T cells are more functional and expandable, and more efficient at tumor eradication than parental CAR T cells. Collectively, our study presents an important and novel strategy that enables CAR T cells to achieve better antitumor immunity, especially in the treatment of solid tumors. .

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