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Understanding the phase transition mechanisms in two-dimensional (2D) materials is a key to precisely tailor their properties at the nanoscale. Molybdenum ditelluride (MoTe2) exhibits multiple phases at room temperature, making it a promising candidate for phase-change applications. Here, we fabricate lateral 2H-Td interfaces with laser irradiation and probe their phase transitions from micro- to atomic scales with in situ heating in the transmission electron microscope (TEM). By encapsulating the MoTe2 with graphene protection layers, we create an in situ reaction cell compatible with atomic resolution imaging. We find that the Td-to-2H phase transition initiates at phase boundaries at low temperatures (200-225 degree C) and propagates anisotropically along the b-axis in a layer-by-layer fashion. We also demonstrate a fully reversible 2H-Td-2H phase transition cycle, which generates a coherent 2H lattice containing inversion domain boundaries. Our results provide insights on fabricating 2D hetero-phase devices with atomically sharp and coherent interfaces., Comment: 38 pages, 5 figures, 9 supplementary figures, and supplementary information

Various services through smartphones or personal computers have become common nowadays. Accordingly, embedded malware is rapidly increasing. The malware is infiltrated by using short message service (SMS), wireless networks, and random calling and makes smartphones bots in botnets. Therefore, in a system without an appropriate deterrent, smartphones are infiltrated easily. In the security threats by malware, random calling has become serious nowadays. To develop the defensive system against random calling and prevent the infiltration of the malware through random calling, it is required to understand the exact process of how to make bots in the botnet. Thus, this research develops a simple and ingenious mobile botnet covert network based on adjustable ID units (SIMBAIDU) to investigate how a botnet network is established by using phone numbers. Perfect octave coding (P8 coding) turns out to be effective in infiltrating smartphones and executing commands, which is used for botnets. The results provide the basic process of P8 coding which is useful for developing defensive systems of smartphones.

Two-dimensional (2D) materials offer an ideal platform to study the strain fields induced by individual atomic defects, yet challenges associated with radiation damage have so far limited electron microscopy methods to probe these atomic-scale strain fields. Here, we demonstrate an approach to probe single-atom defects with sub-picometer precision in a monolayer 2D transition metal dichalcogenide, WSe2-2xTe2x. We utilize deep learning to mine large data sets of aberration-corrected scanning transmission electron microscopy images to locate and classify point defects. By combining hundreds of images of nominally identical defects, we generate high signal-to-noise class averages which allow us to measure 2D atomic spacings with up to 0.2 pm precision. Our methods reveal that Se vacancies introduce complex, oscillating strain fields in the WSe2-2xTe2x lattice that correspond to alternating rings of lattice expansion and contraction. These results indicate the potential impact of computer vision for the development of high-precision electron microscopy methods for beam-sensitive materials.

Summary A series of readily accessible and scalable benzo[1,2-b:4,5-b′]dithiophene (BDT)-2,5-dithienyl-thieno[3,4-c]pyrrole-4,6-dione (TPD-T2)-based donor polymers are utilized in organic photovoltaic (OPV) cells blended with the non-fullerene acceptor IT-4F. All polymers readily dissolve in chlorine-free solvents such as xylene, and the corresponding photoactive blend films can be processed in ambient from this solvent to fabricate cells with power conversion efficiencies (PCEs) >12%–14%. Furthermore, the blend processing and OPV metrics are remarkably insensitive to the processing methodology (spin coating versus blade coating), processing solvent, polymer molecular mass and dispersity index, and the results were rationalized by UV-vis, PL, fsTA, AFM, TEM, GIWAXS, and SCLC measurements. These properties enable the first OPV modules, processed in ambient from a benign solvent, with a certified PCE of 10.1% for an area of 20.4 cm2 and >7% after light soaking. The same module also delivers a power of ∼40 μW/cm2 (PCE ∼22%) under indoor lighting.

This study investigates the effects from the dissemination of price information on the price-volume relation of American depositary receipts (ADRs). We construct a measure for the sensitivity of ADR investors to price information from their underlying stocks in Asia-Pacific markets and to explore the effect of the dissemination of price information. The empirical results show that the effect of information dissemination induces the price-volume relation of ADRs to become asymmetric. These results indicate that the price information disseminated from the underlying stocks affects the trading decisions of ADR investors. Furthermore, we find that ADR investors are more sensitive to the price information of underlying stocks in more developed financial systems and economies as well as in stronger legal environments.

This article examines the impacts of industry competition on the leader-follower effects in different earnings management activities. The empirical results show that there are the leader-follower e...

Hyperuniform many-body systems in $d$-dimensional Euclidean space ${R}^{d}$ are characterized by completely suppressed (normalized) infinite-wavelength density fluctuations, and appear to be endowed with novel exotic physical properties. Recently, hyperuniform systems of disordered varieties have been observed in the context of various atomic-scale two-dimensional (2D) materials. In this work, we analyze the effects of localized defects on the density fluctuations across length scales and on the hyperuniformity property of experimental samples of 2D transition metal dichalcogenides. In particular, we extract atomic coordinates from time series annular dark field-scanning transmission electron microscopy imaging data of 2D tungsten chalcogenides with the 2H structure (Te-doped 2H-${\mathrm{WSe}}_{2}$) showing continuous development and evolution of electron-beam-induced defects, and construct the corresponding chemical-bonding informed coordination networks between the atoms. We then compute a variety of pair statistics and bond-orientational statistics to characterize the samples. At low defect concentrations, the corresponding materials are nearly hyperuniform, characterized by significantly suppressed scattering at the zero wave-number limit (omitting forward/ballistic scattering). As more defects are introduced, the (approximate) hyperuniformity of the materials is gradually destroyed, and the system becomes nonhyperuniform even when the material still contains a significant amount of crystalline regions. At high defect concentrations, the structures become antihyperuniform with diverging (normalized) large-scale density fluctuations, mimicking those typically observed at the thermal critical points associated with phase transitions. Overall, the defected materials possess varying degrees of orientation order, and there is apparently no intermediate hexatic phase emerging. To understand the observed nearly hyperuniform density fluctuations in the slightly defected materials, we construct a minimalist structural model and demonstrate that the experimental samples can be essentially viewed as perturbed honeycomb crystals with small correlated displacements and double chalcogen vacancies. Moreover, the small correlated displacements alone can significantly degrade hyperuniformity of the perfect honeycomb structure. Therefore, even a small amount of vacancies, when coupled with correlated displacements, can completely destroy hyperuniformity of the system.

Many firms are aware that eco-innovation is an important issue in resource management practice due to its contribution to firms’ competencies and capabilities. Eco-innovation represents a differentiating attribute for sustainable business in fiercely competitive environments. However, prior studies have not examined the role of eco-innovation in sustainable development through hierarchical structural analysis of resource management practice to address firms’ capabilities and competencies; in particular, the attributes contain qualitative information and quantitative data. This study proposes a hybrid method comprising the fuzzy Delphi method, importance-performance analysis, and a decision-making trial and evaluation laboratory to rank the attributes and assist firms in decision-making. The result supports the use of advanced eco-friendly technologies and the selection of potential talent to support eco-innovation and foster changes in strategic vision, management structure, and administrative procedures. Clear policies and procedures, mutual trust and respect, and sales staff characteristics are needed to improve firm performance toward sustainable business.

Sustainable tourism has been receiving increasing attention from the academic and business sectors due to uncertainty, environmental pollution, and the delivery of uncreative tourism products and fragmented, temporary and inadequate services. However, due to the uncertainties, collaboration is a critical attribute in the tourism industry in terms of sustainability. Although many attributes have been addressed in the literature, a comprehensive measurement structure remains unexplored in this sector. This study attempts to evaluate the causal inter-relationships among the attributes, explore the hierarchical inter-relationships and identify the powers that drive dependence among the attributes to improve sustainable performance by employing a combined method of fuzzy set theory, a decision-making trial and evaluation and interpretive structural modeling. A set of four aspects—socio-cultures, economics, environments, and collaborations—that include 24 criteria are introduced from the literature and are based on experts' opinions. The results obtained show that collaboration is the strongest causal attribute driving the others in sustainable tourism, revealing that community well-being, guest cultures, information sharing, transparency, and incentive alignment have exhibited the greatest levels of driving and dependence power in the structure of the industry. These attributes are the most effective at enhancing the industry's sustainable performance. In addition, theoretical and managerial implications are discussed to enhance the value of our findings.

This study contributes to the understanding of the effect of influential attributes on reduced energy consumption behavior. The European Union aims to replace at least 80% of electricity meters with smart meters by 2020. With smart meters it could provide energy information on real-time consumption. The smart meter is used to explore energy consumer behavior with socio-demographics, pro-environmental behavior, and goal directed behavior. However, at present there are few studies that investigate these influential attributes on energy consumers. Hence, this study is to understand the effect of influential attributes on reduced energy consumption behavior. Energy consumer information was controlled to provide feedback to the participants based on the product design strategy of persuasive technology. The respondents adapted their energy consumption behavior during this analytical approach. The data was collected and analyzed based on statistical methods. The result shows the influential attributes on reduced energy consumption behavior for design references.

The goal of this study is to explore the effect of financial openness in emerging markets on the domestic financial market liquidity and then to clarify the linkage between financial openness and market liquidity. The empirical results show that higher the degree of the financial market openness enhances the domestic financial market liquidity, and the effect of the financial market openness on the emerging markets is more significance than the developed markets. We expect the empirical results of this study can provide a new insight into the development of emerging financial markets.

The contribution of this study is to apply a hybrid method to identify critical green supply chain practices (GSCP) based on importance and performance level under linguistic preferences. The leather industry in Bangladesh is facing acute pressure to minimize environmental pollution. Proper assessment of GSCP ensure effective implementation and thereby helping the industry face environmental challenges. However, there is lack of methods available for the assessment of GSCP concerning their importance and performance attributes under linguistic preferences. This study uses fuzzy set theory to handle fuzziness of human perceptions since the GSCP attributes usually expressed in linguistic preferences. Then, fuzzy importance and performance analysis (FIPA) approach was applied to identify GSCP importance and performance levels. Moreover, FIPA matrix was plotted to determine the critical GSCP as enablers of environmental performance enhancement. Additionally, a comprehensive measurement structure is also absent that requires the inclusion of supply chain partners as aspects. The objective is to assess GSCP based on importance and performance level. The study reveals that supplier and manufacturer viewpoints are the most critical aspects. Furthermore, designing for recycling water and minimizing waste during manufacturing, participation in an ISO 14001 environmental certification system, selection of suitable suppliers based on environmental criteria are the critical GSCP attributes. The managerial implications also are presented. The study presents certain limitations and thus proposes future studies.

The purpose of this paper is to examine whether executive stock-based compensation incentives induce the relation between accrual-based earnings management (AEM) and real earnings management (REM) to become asymmetric. The empirical results show that there is the substitute relation between AEM and REM when CEOs have the lowest degree of stock-based compensation incentives. However, there is the complementary relation between AEM and REM when CEOs have the median degree of stock-based compensation incentives. Moreover, the results also present a trade-off relation exists in the highest degree financial incentives during the post-SOX period, but this relation does not exist in the same regime during the pre-SOX period. These findings provide new insight into executive compensation mechanism for shareholders, investors, and regulators, resulting in the efficiency to prevent managers from obtaining private gains at shareholders’ expense.

This study explore the effects of different levels of stock-based reward incentives on the value of corporate cash holdings by the PTM developed by Hansen (1999). Empirical results revealed that the positive effects of executives? cash holdings on corporate value increase concurrently with the sensitivity of the value of their stock-based rewards on the standard deviation of corporate stock returns. Conversely, the positive effects of executives? cash holdings on corporate value diminish concurrently with managerial incentives. Furthermore, the excess cash in companies with strong managerial incentives positively affects corporate value. However, these effects have no substantial economic effects. Finally, the outcomes of this study can serve as a reference for companies and competent authorities when formulating reward agreements to inhibit agency problems by taking into account the positive and negative effects of reward incentives, thereby protecting shareholders? interests and ensuring capital market stability.

Glioblastoma multiforme (GBM), a grade IV astrocytoma, is the most aggressive and formidable brain malignancy. It has a predictably poor prognosis and unique medical challenges. The high recurrence of GBM in clinical practice leads to an average survival of only 12–18 months after diagnosis. One of the critical issues in GBM treatment is the physiological restriction of antitumor drugs from traversing the blood–brain barrier (BBB). In recent years, the development of nanoparticles (NPs) has enhanced the ability of pharmaceuticals to cross the BBB for GBM treatment. In addition, the fabrication and design of nanoparticulate carriers determine the category of medicinal substance that the particles can carry, such as a high molecular weight hydrophobic/hydrophilic drug, a gene segment, or an imaging contrast agent. Surface modification of NPs also ameliorates the biocompatibility of numerous antitumor remedies. Thus, the capability of nanocarriers provides a high likelihood of managing GBM, by means of gene therapy, chemotherapy, anti-angiogenesis therapy or diagnosis. This review focuses on GBM treatment by inhibiting angiogenesis and using nanocarriers. Development of innovative drug delivery systems will also be highlighted in various aspects, including effective permeation of the BBB, and may provide inspiration for salvage chemotherapy and adjuvant care of patients with GBM in future clinical application.

Tor anonymous network is to protect the privacies of the users in the Internet. In this paper, our goal is to research what potential security risks and vulnerabilities we will encounter when using Tor anonymous network. We try to find some determined results from the perspective of an attacker. Using the system architecture of Tor anonymous network and combining the concept of man-in-the-middle (MITM) attack, we design a system for experiments to instigate the attacks in practice. Finally, we discuss and analyze the potential security threats and risks of using Tor anonymous network based on our results of experiments.

Nowadays, antivirus is one of the most popular tools used to protect computer systems. Diverse antivirus vendors are established to protect their customers against malware. However, antivirus is facing some critical problems, such as significant detection windows, vulnerability inside antivirus, and long scanning time. In this paper, we recommend a cloud-based real-time defense mechanism named Skywalker to allow users to safely utilize antivirus without the above problems. After Skywalker is installed in a host, the host does not need to install any antivirus. However, Skywalker guarantees that the host only executes programs that have been verified by a cloud-based scanner, such as VirusTotal. VirusTotal uses 56 antivirus engines to check whether a program is malware. Research shows that the more antivirus engines are used, the more accurate the result is. Because the above scan is performed right before the execution of every program, Skywalker provides 24/7 real-time protection to a system. Besides, Skywalker eliminates the need to spend a lot of time scanning all files in a host. Experimental results show that after a program has been executed once, it takes Skywalker, at most, 0.47091 s to start the program again. Meanwhile, VirusTotal provides a secure protection to client hosts.

Benzene-based 1,1-dicyanomethylene-3-indanone (IC) derivatives have been widely utilized as the end-group to construct acceptor-donor-acceptor type nonfullerene acceptors (A-D-A type NFAs). The extension of the end-group conjugation of nonfullerene acceptors (NFAs) is a rational strategy to facilitate intermolecular stacking of the end-groups which are responsible for efficient electron transportation. A bicyclic benzothiophene-based end-group acceptor, 2-(3-oxo-2,3-dihydro-1

Although the success of graphene research has opened up a new route for wearable electronic and optoelectronic devices, producing graphene with controllable quality and cost-effective growth on a large scale remains challenging due to the lack of understanding about its growth kinetics. Domain boundaries interrupt lattice continuity of graphene; therefore, lowering the nucleation density at the initial stage of graphene growth in the chemical vapor deposition (CVD) process is beneficial for improving the quality of graphene for applications. Herein, we show that by forming an oxide passivation layer on Cu substrates before CVD graphene growth, graphene nucleation density can be effectively decreased. The nucleation mechanism in the presence of an oxide passivation layer is of interest. The analysis of graphene growth kinetics suggests that the thickness of the boundary layer for mass transfer on the substrate surface plays an important role in controlling the reduction rate of the oxide passivation layer. A thick boundary layer created under slow gas flow causes slow reduction of the oxide passivation layer, making finite sites for graphene nucleation. The domain density in a graphene layer is therefore significantly reduced. Graphene sheets of various domain densities (ranging from 104 to 1 mm−2) can be fabricated by suitably choosing the growth parameters. The graphene sheet with a lower density of domain boundaries exhibits better electrical conductivities.

This study investigates the mediation effect of the pay-risk sensitivity of CEOs on the relation between risky investment and bank performance over the sample period of 2000 to 2007. The empirical results of the study show that CEOs of BHCs engage in more private MBSs will increase their pay-risk sensitivity incentives, and then induces the relation between risky investment and bank performance to become negative. These results imply that the pay-risk sensitivity incentives indirectly induce manager to increase his own benefits at the expense of shareholders. Furthermore, we classify CEOs of BHCs as three levels of overconfidence, and find that the pay-risk sensitivity incentive has a mediation effect on the relation between private MBSs and firm performance in excessively overconfident CEOs group, implying that the levels of CEOs confidence should be considered while compensation committee designs a flawless contract for encouraging managers put shareholders' best interests in front of theirs.

Ferrimagnetic materials combine the advantages of the low magnetic moment of an antiferromagnet and the ease of realizing magnetic reading of a ferromagnet. Recently, it was demonstrated that compensated ferrimagnetic half metals can be realized in Heusler alloys, where high spin polarization, zero magnetic moment, and low magnetic damping can be achieved at the same time. In this work, by studying the spin-orbit torque induced switching in the Heusler alloy Mn2 Ru1- x Ga, it is found that efficient current-induced magnetic switching can be realized in a nearly compensated sample with strong perpendicular anisotropy and large film thickness. This work demonstrates the possibility of employing compensated Heusler alloys for fast, energy-efficient spintronic devices.

This study constructs a theory of eco-innovation in circular agri-business. Although previous studies have discussed eco-innovation in circular agri-business, they did not address eco-innovation from the perspective of a closed-loop sustainable supply chain. Hence, this study applied the fuzzy TOPSIS method to conduct the analysis and determine the interrelationship between eco-innovation and the closed-loop concept. The results are consistent with the theory and a significant improvement in terms of the decisive attributes. The findings suggest that improving water management, relationships with suppliers, knowledge sharing, environmental management systems, and new product and service development are the most effective and efficient ways to build eco-innovation in circular agri-business. The managerial and theoretical implications are discussed.

We present a facile synthesis method to make a new ladder-type heptacyclic dithienobenzofluorene (DTBF) framework, where the central 2,7-fluorene unit is covalently fastened with two external thiophenes via two CC bridges. A dieneyne-containing precursor undergoes DBU-induced double benzannulation to regiospecifically introduce two solubilizing 2-octyldodecyl side chains at 5,10-positions of DTBF. The rigid and coplanar Br-DTBF monomer with sufficient solubility was copolymerized with 5,6-difluoro-4,7-bis(5-(trimethylstannyl)thiophen-2-yl)benzo[c][1,2,5]thiadiazole (Sn-DTFBT) and 5,10-bis(5-(trimethylstannyl)thiophen-2-yl)naphtho[1,2-c:5,6-c′]bis([1,2,5]thiadiazole) (Sn-DTNT) via Stille coupling to furnish two donor–acceptor copolymers, PDTBFFBT and PDTBFNT, respectively. Their thermal, optical, electrochemical, molecular stacking and photovoltaic properties are investigated. PDTBFNT has a higher molecular weight, smaller optical and electrochemical band gaps, and stronger solid-state packing than PDTBFFBT. DFT calculations were carried out to gain insight into the electronic and structural properties of DTBF and its derivatives. Bulk heterojunction solar devices with the ITO/ZnO/polymers:PC71BM/MoO3/Ag configuration were fabricated. By adding 5 vol% diphenyl ether (DPE) as an additive, PDTBFNT:PC71BM and PDTBFFBT:PC71BM devices achieved the power conversion efficiencies of 5.22% and 2.68%, respectively. The superior efficiency of PDTBFNT over PDTBFFBT is attributed to the better LUMO energy alignment between PDTBFNT and PC71BM and the face-on π-stacking of PDTBFNT in the active layer. Moreover, PDTBFNT exhibited a higher field-effect transistor hole mobility of 1.90 × 10−2 cm2 V−1 s−1 than PDTBFFBT with a value of 3.96 × 10−3 cm2 V−1 s−1.

The study explores the structural breaks in the correlations between nine Asian stock markets and the US stock market. This study employs the EGARCH-DCC model to obtain the daily correlations between Asian and the US stock markets, and use the method of Carrion-i-Silvestre (2005) to detect the structural breaks. The empirical results indicate there are multiple breaks in the correlations and imply that both 2001 Dot-com bubble and 2008 financial crisis have impacts on the correlations between Asian and the US markets. These results bring the crucial insights for the portfolio strategy of international investors.

A new strategy to synthesize 4,9- and 5,10-dialkylated α-aNDTs as well as 4,9- and 5,10-dialkylated β-aNDTs is described. Four isomeric precursors with different dithienyl-ene-diyne arrangements undergo base-induced double 6π-cyclization to construct the central naphthalene cores, leading to the formation of the regiospecific products. These 2,7-distannylated dialkylated aNDT-based monomers can be used for Stille cross-coupling to produce promising conjugated materials for various optoelectronic applications.

We analyze the possibility of nonlinear adjustment and unknown smooth breaks in the stationarity of real exchange rates in the Group of 20 (G-20) countries over a period from January 1994 to April 2010 by applying the Panel SURADF test with Fourier function. Although most of the results from a univariate unit root test and panel unit root test indicated a fail to reject the unit root null hypothesis in the real exchange rates of G-20, the results of the Panel SURADF test with Fourier function show a strong rejection of non-stationarity of real exchange rates among the G-20 and imply that PPP is valid for all in the G-20. The evidence also implies that there are nonlinearity and smooth breaks in real exchange rates of G-20 countries.