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We examine how the trade shock from China influences the behavior and investment performance of overconfident CEOs in U.S. firms. We show that the rise of Chinese import competition curbs investments and improves investment value and acquisition performance for firms with overconfident CEOs. Intensified Chinese product competition also reduces the incentives for these firms to expand assets, invest out of cash flows, pursue aggressive financial policies, and increase risk exposure, and enhances their incentives to buy back shares. Overall, the evidence suggests that product market competition is an effective external governance mechanism for curbing the adverse effects of managerial overconfidence.

Sediment contamination in Taiwan is a critical environmental problem because it threatens human health through food chains and the local ecosystem as well. Er-Ren River (ERR) in southern Taiwan is one of the most polluted and its sediments have been severely contaminated by hydrophobic organic compounds (HOCs). Among all HOCs, polychlorinated biphenyls (PCBs) have been detected at high levels while hexachlorobenzene (HCB) has been most frequently detected. Due to their higher Kow values and lower biodegradability, they can be biomagnified through trophic levels and consequently pose high risks to humans and the ecosystem. This field study is to demonstrate an effective remediation technology on sediments contaminated by Aroclor 1254 and HCB by coupling in situ phase-inversion emulsification and biological reductive dechlorination (ISPIE/BiRD). By using real contaminated sediment with weathered and freshly-added contaminants, a single ISPIE operation can remove about 62% and 60% of weathered Aroclor 1254 and HCB, respectively. For weathered HCB and Aroclor 1254, the total removal could reach as high as 98% in 70 days. Metagenomic results showed that heat selection during ISPIE significantly changed the diversity and species evenness of the microbial community and that the Dehalococcoides were not positively correlated with the PCB removals. Instead, heat-tolerant archaea, Methanosaeta spp., may play much more important roles in the subsequent biological dechlorination. These results strongly support that ISPIE/BiRD is highly feasible on a full-scale field remediation and that this new microbial consortium could be a highly effective tool for bioremediation of HOC-contaminated sediments.

The hippocampus is a key brain structure for cognitive and emotional functions. Among the hippocampal subregions, the dentate gyrus (DG) is the first station that receives multimodal sensory information from the cortex. Local-circuit inhibitory GABAergic interneurons (INs) regulate the excitation-inhibition balance in the DG principal neurons (PNs) and therefore are critical for information processing. Similar to PNs, GABAergic INs also receive distinct inhibitory inputs. Among various classes of INs, vasoactive intestinal polypeptide-expressing (VIP+ ) INs preferentially target other INs in several brain regions and thereby directly modulate the GABAergic system. However, the morpho-physiological characteristics and postsynaptic targets of VIP+ INs in the DG are poorly understood. Here, we report that VIP+ INs in the mouse DG are highly heterogeneous based on their morpho-physiological characteristics. In approximately two-thirds of morphologically reconstructed cells, their axons ramify in the hilus. The remaining cells project their axons exclusively to the molecular layer (15%), to both the molecular layer and hilus (10%), or throughout the entire DG layers (8%). Generally, VIP+ INs display variable intrinsic properties and discharge patterns without clear correlation with their morphologies. Finally, VIP+ INs are recruited with a long latency in response to theta-band cortical inputs and preferentially innervate GABAergic INs over glutamatergic PNs. In summary, VIP+ INs in the DG are composed of highly diverse subpopulations and control the DG output via disinhibition.

We study industrial reactions to both the global financial crisis of 2008 and the COVID-19 pandemic. Although most industries in the U.S. suffered from the two events, the stock performance of most industries started to recover following the announcements of quantitative easing. Our results indicate that quantitative easing is effective in boosting investor confidence. We also find that the effect of quantitative easing in 2020 on stock performance is more significant for the industries that are more affected by the pandemic.

This paper presents a system for predicting the current price of lead based on artificial neural networks and NARX models. Using the London Metal Exchange (LME) spot metal price dataset for about 30 years, the proposed smart lead price prediction system can achieve prediction error of less than 10% (that‘s, approximately equal to $100). This article believes that in the near future, it can be expanded to predict futures prices from lead to other industries and even precious metals.

In the era of global economic integration, currencies are used for various transactions, and different currencies need to be converted. Different exchange rates will be generated in different countries during the conversion process. Different exchange differences are generated, so a method can be used to FPP, so the purpose of this article is to consolidate related papers using artificial neural networks (ANNs) in AI, and analyze the MSE, MAE, etc. of these papers. And compare these methods.

Breast cancer has become the second leading cause of cancer-related mortality in female wherein more than 90% of breast cancer-related death results from cancer metastasis to distant organs at advanced stage. The purpose of this study is to develop biodegradable nanoparticles composed of natural polypeptides and calcium phosphate (CaP) with sequential pH-responsivity to tumor microenvironments for active targeted drug delivery. Two different amphiphilic copolymers, poly(ethylene glycol) 3400 -aconityl linkage-poly( l -glutamic acid) 15 -poly( l -histidine) 10 -poly( l -leucine) 10 and LyP1-poly(ethylene glycol) 1100 -poly( l -glutamic acid) 15 -poly( l -histidine) 10 -poly( l -leucine) 10 , were exploited to self-assemble into micelles in aqueous phase. The bio-stable nanoparticles provide three distinct functional domains: the anionic PGlu shell for CaP mineralization, the protonation of PHis segment for facilitating anticancer drug release at target site, and the hydrophobic core of PLeu for encapsulation of anticancer drugs. Furthermore, the hydrated PEG outer corona is used for prolonging circulation time, while the active targeting ligand, LyP-1, is served to bind to breast cancer cells and lymphatic endothelial cells in tumor for inhibiting metastasis. Mineralized DOX-loaded nanoparticles (M-DOX NPs) efficiently prevent the drug leakage at physiological pH value and facilitate the encapsulated drug release at acidic condition when compared to DOX-loaded nanoparticles (DOX NPs). M-DOX NPs with LyP-1 targeting ligand effectively accumulated in MDA-MB-231 breast cancer cells. The inhibition effect on cell proliferation also enhances with time, illustrating the prominent anti-tumor efficacy. Moreover, the in vitro metastatic inhibition model shows the profound inhibition effect of inhibitory nanoparticles. In brief, this self-assembling peptide-based drug delivery nanocarrier with multifunctionality and programmable pH-sensitivity is of great promise and potential for anti-cancer therapy. Statement of Significance This tailored-design polypeptide-based nanoparticles with self-assembling and programmable stimulus-responsive properties enable to 1) have stable pH in physiological value with a low level of drug loss and effectively release the encapsulated drug with pH variations according to the tumor microenvironment, 2) enhance targeting ability to hard-to-treat breast cancer cells and activate endothelial cells (tumor region), 3) significantly inhibit the growth and prevent from malignant metastasis of cancer cells in consonance with promising anti-tumor efficacy, and 4) make tumors stick to localized position so that these confined solid tumors can be more accessible by different treatment modalities. This work contributes to designing a programmable pH-responsive drug delivery system based on the tailor-designed polypeptides.

Given the needs of data-intensive web services and cloud computing applications, storage centers play an important role in serving the demanded data access while jointly considering low cost, qualified performance, and good scalability. To manage peak workloads with performance requirements for read/write latencies, overprovisioning more storage nodes is common but also increases total cost as well as power consumption. Recently, due to the growing capacity and dropping price, NAND-flash-based Solid-State Drives (SSDs) have become an attractive storage solution in datacenters. In this work, we exploit the write heterogeneity in Multi-Level-Cell (MLC) NAND flash memory to meet Service-Level Objectives (SLOs) of applications and to avoid storage overprovision. In MLC NAND flash memory, a memory cell can be programmed as a Single-Level Cell (SLC) or a multi-level cell at runtime, and SLC writes take shorter latency with the cost of larger consumed capacity. The proposed SLO-aware morphable SSD design seeks to meet the SLO requirement by deciding the write mode of each write request while minimizing the number of SLC writes. Experimental results show that the proposed design meets the SLO requirement for all of the tested I/O traces with less than 2.8 percent extra erase counts in average, while conventional MLC SSDs require up to 2.375 times storage overprovision to meet the SLO requirement.

We examine the role of equity underwriting relationships in subsequent mergers and acquisitions (M&As). Firms, either the bidders or targets, tend to choose their M&A advisors with prior equity underwriting relationships. Consistent with the cost-saving hypothesis, retaining their prior underwriters as future advisors is related to cost reduction in the M&A advisory. Firms also experience shorter deal duration if they hire relationship advisors. This study contributes to the further understanding of how firms derive value from investment bank relationships.

This study proposes chief executive officer (CEO) overconfidence to be an alternative explanation to corporate cash holdings. We find positive effects of CEO overconfidence on the level of cash holdings and the value of cash, which are mainly due to the investment environments faced by firms. The positive effects of CEO overconfidence on cash holdings level and cash value are barely affected by the traditional motives of cash holdings based on trade-off and agency theories. The analysis of cash sources further explains why firms with overconfident CEOs can aggressively pursue risky investments and maintain large cash holdings at the same time. Although the prior literature indicates that overconfident CEOs tend to avoid equity issues for their capital investments, the contribution to cash savings from equity is higher than that from debt. Additional robustness tests also support our empirical findings.

Brain injury is a devastating medical condition and represents a major health problem. Tissue and organ reconstruction have been regarded as promising therapeutic strategies. Here, we propose a regenerative methodology focusing on the provision of functionalized nanopeptide scaffolds to facilitate angiogenesis and neurogenesis at the brain injury site. The peptide RADA16-SVVYGLR undergoes self-assembly to construct an interconnected network with intertwining nanofibers, and can be controlled to display various physicochemical properties by the adjustment of microenvironmental factors such as pH and ion concentration. Such scaffolds can support endothelial cells to form tube-like structures and neural stem cells to survive and proliferate. In an in vivo zebrafish brain injury model, sprouting angiogenesis and developmental neurogenesis were achieved, and functional recovery of the severed optic tectum was enhanced in RADA16-SVVYGLR hydrogel-implanted zebrafish. This nanopeptide hydrogel was non-toxic to zebrafish embryos during early developmental stages. This angiogenic self-assembling peptide hydrogel had programmable physical properties, good biocompatibility, and regenerative ability for functional recovery in the injured brain. We suggest that functionalized self-assembling peptides encapsulated with neural stem cells or used alone could be an attractive and effective therapeutic modality for brain injury and diseases (e.g., trauma, stroke, tumor, degenerative neurological disorders, etc.).

The development of osteochondral tissue engineering is an important issue for the treatment of traumatic injury or aging associated joint disease. However, the different compositions and mechanical properties of cartilage and subchondral bone show the complexity of this tissue interface, making it challenging for the design and fabrication of osteochondral graft substitute. In this study, a bilayer scaffold is developed to promote the regeneration of osteochondral tissue within a single integrated construct. It has the capacity to serve as a gene delivery platform to promote transfection of human mesenchymal stem cells (hMSCs) and the functional osteochondral tissues formation. For the subchondral bone layer, the bone matrix with organic (type I collagen, Col) and inorganic (hydroxyapatite, Hap) composite scaffold has been developed through mineralization of hydroxyapatite nanocrystals oriented growth on collagen fibrils. We also prepare multi-shell nanoparticles in different layers with a calcium phosphate core and DNA/calcium phosphate shells conjugated with polyethyleneimine to act as non-viral vectors for delivery of plasmid DNA encoding BMP2 and TGF-β3, respectively. Microbial transglutaminase is used as a cross-linking agent to crosslink the bilayer scaffold. The ability of this scaffold to act as a gene-activated matrix is demonstrated with successful transfection efficiency. The results show that the sustained release of plasmids from gene-activated matrix can promote prolonged transgene expression and stimulate hMSCs differentiation into osteogenic and chondrogenic lineages by spatial and temporal control within the bilayer composite scaffold. This improved delivery method may enhance the functionalized composite graft to accelerate healing process for osteochondral tissue regeneration. Statement of Significance In this study, a gene-activated matrix (GAM) to promote the growth of both cartilage and subchondral bone within a single integrated construct is developed. It has the capacity to promote transfection of human mesenchymal stem cells (hMSCs) and the functional osteochondral tissues formation. The results show that the sustained release of plasmids including TGF-beta and BMP-2 from GAM could promote prolonged transgene expression and stimulate hMSCs differentiation into the osteogenic and chondrogenic lineages by spatial control manner. This improved delivery method should enhance the functionalized composite graft to accelerate healing process in vitro and in vivo for osteochondral tissue regeneration.

In these years, the artificial nerve guidance conduit (NGC) has been developed as an alternative way to repair peripheral nerve injury. Unlike autologous nerve graft, the artificial NGC without proper stimulating factors and guidance cues still cannot obtain satisfactory prognosis for clinical patients. In this study, a biodegradable polymer-based implantable device has been developed and characterized. By incorporating three stimulating factors: (1) micro-patterned surface that can directionally guide the axon as physical cue; (2) neurotrophic gradient membrane that can continually attract axon outgrowth from the proximal to distal stump as chemical cue; (3) Schwann cells (SCs) that can support the growth of neurite and form myelin sheath around axon as biological cue, we expect that this construct can be used as a promising NGC for peripheral nerve regeneration. The results showed that the micro-patterned surface with specific dimension of channels and chambers can be precisely fabricated by laser ablation. Attachment and directional extension of differentiated neural stem cells (NSCs) were observed in micro-channels. The gradient distribution of nerve growth factor 7S on gelatin membrane was successfully achieved. Significant improvement in neurite length and increase in neuronal gene expressions were also noticed in higher concentration region. When co-culturing with SCs, NSCs can differentiate toward neuronal cells with strong expression of mature neuronal markers: βIII tubulin and microtubule-associated protein-2 (Map 2). Meanwhile, myelin basic protein was also observed, suggesting that SCs can provide biological support to neuronal cells in vitro. In the future, this advanced artificial NGC may be used as implantable prosthesis for the treatment of peripheral nerve injury with better functional recovery.

Novel organic dyes that consist of either a benzo[1,2- b :4,5- b ′]dithiophene or a benzo[1,2- b :4,5- b ′]difuran core exhibited remarkable solar-to-energy conversion efficiency in dye-sensitized solar cells. The planar geometry of bridge moiety and its bulky substituents helped the dyes to form a high quality monolayer on the surface of titanium oxide. A typical device displayed photon-to-current conversion efficiency 60% in the region of 380–575 nm, a short-circuit photocurrent density 13.45 mA cm −2 , an open-circuit photovoltage 0.72 V, and a fill factor 0.63, corresponding to an overall conversion efficiency 6.12%. In a test of using deoxycholic acid as a co-absorbent, an improvement of quantum efficiencies 8.37% was observed for certain compounds. However, for others the quantum efficiency decreased in 6.60–7.91%. The latter result indicated that the quality of some films cannot be further improved by the addition of deoxycholic acid. The photophysical properties were analyzed with the aid of TDDFT.

Organic dyes that consist of an anthracene moiety between a triphenylamine donor group and a cyanoacrylic acid acceptor group displayed remarkable solar-to-energy conversion efficiency in dye-sensitized solar cells. The planar geometry of anthracene and its bulky substituents helped the dyes to form a high quality monolayer on the surface of TiO 2 . A typical device made with the dye AN-Bu displayed a maximal photon-to-current conversion efficiency (IPCE) 65% in the region of 350–510 nm, a short-circuit photocurrent density ( J sc ) 12.78 mA cm −2 , an open-circuit photovoltage ( V oc ) 0.73 V, and a fill factor (FF) 0.67, corresponding to an overall conversion efficiency 6.23%. In an experiment of using deoxycholic acid (DCA) as a co-absorbent, the values of V oc stayed in a similar range, yet the values of J sc were reduced in ca. 11% due to a decrease of loading amounts. This result indicated that the quality of the dye films cannot be further improved by the adding of DCA. The photophysical properties were analyzed with the aid of a time-dependent density functional theory (TDDFT) model with the B3LYP functional.

In the previous study (Liaw and Kuo, 2012), a preliminary version of the Time Division Multiple Access (TDMA)-based communication platform had been successfully tested to provide the function of wireless hopping data transmission. However, that design was only valid for the consecutive nodes which are close-by. A modified design was proposed in (Liaw, Wang and Lai, 2013) by using self-design Wireless Sensor Network (WSN) nodes to investigate the feasibility of the application in short range data communication. The effect of the packet size and distance between two consecutive nodes on the performance of remote data transmission was also studied. Instead, in this paper, we propose another scheme for time division wireless monitoring transmission protocol (TDWMTP). This design is based on IEEE 802.11a standard with the transmission method of TDMA (Time Division Multiple Access) to enhance and implement the function proposed in (Liaw, Wang and Lai, 2013). Experimental results demonstrate the success of the proposed design.

Intriguing functionalities at nano-sized domain walls have recently spawned a new paradigm for developing novel nanoelectronics due to versatile characteristics. In this study, we explore a new scenario to modulate the local conduction of ferroic domain walls. Three controlling parameters, i.e., external electrical field, magnetic field and light, are introduced to the 90° domain walls (90° DWs) of BiFeO3. Electrical modulation is realized by electrical transport, where the mobility of 90° DWs can be altered by gating voltage. We further use the ferromagnetic/antiferromagnetic coupling to reveal the inherent magnetism at the DWs. With an established magnetic nature, magnetotransport has been conducted to introduce magnetic controlling parameter, where a giant positive magnetoresistance change can be observed up to 200%. In addition, light modulated conduction, a core factor for multifunctional applications, is successfully demonstrated (current enhancement by a factor of 2 with 11 W white lamp). These results offer new insights to discover the tunability of domain wall nanoelectronics.

In this study, we propose a novel server load balancing scheme. Server load balancing is known to be a critical mechanism in network-based information service. Most of existing schemes don't take servers' loadings into account, which might fail to make the loadings of all servers evenly and drive the server system to work on the brink of being over-loaded and/or out of function. The proposed scheme aims at preventing the occurrence of malfunction and saving the power consumption of the server system under a low loading while providing a better performance in response time. All connection requests are firstly distributed into one server until a pre-specified portion of its maximum allowed serving load is achieved. The following requests are then served by another server in the same way. The experimental results demonstrate the feasibility of the proposed scheme.