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In this study, we investigate the potential impacts of the thermo-diffusion and diffusion-thermo effects on electro-osmotic flow of Maxwell nanofluid across the stretching sheet. Magnetic and electric field over Darcy-Forchheimer flow and chem-ical reaction are also included. This study is vital in areas such as microfluidics, medical applications, and thermal man-agement, where manipulating nanofluids under electromagnetic fields is essential. Through similarity transformation, the governing equations are turned into a collection of non-linear ordinary differential equations. The numerical results for the changed equations are obtained using the fifth order Runge-Kutta-Fehlberg technique with a shooting method. It has been established that if the Forchheimer number and electro-osmotic parameter increase, the velocity profile drops. As the dif-fusion-thermo effect grows so does the temperature profile. Similarly, the thermo-diffusion effect increases along with the concentration profile. The skin friction coefficient decreases by 10% and 23%, for the magnetic parameter increases from 0.4 to 2 and the Forchheimer number rises from 1 to 5, respectively. Additionally, with an increase in the Dufour number from 1.5 to 2, the Nusselt number decreases by 9%, while the Sherwood number increases by 33%. This research provides a more comprehensive analytical framework by integrating multiple physical effects such as Soret and Dufour effects, magnetic and electric fields, and porous media, thereby enhancing applications in microfluidic devices for precise fluid control, biomedical engineering for improved drug delivery and tissue engineering, thermal management for more efficient electronic cooling systems, environmental remediation for effective pollution control, and materials science for developing smart materials and nanocomposites.

This article describes the incompressible two-dimensional heat and mass transfer of an electrically conducting second-grade fluid flow in a porous medium with Hall and ion slip effects, diffusion thermal effects, and radiation absorption effects. It is assumed that the fluid is a gray, absorbing–emitting but non-scattering medium and the Rosseland approximation is used to describe the radiative heat flux in the energy equation. It is assumed that the liquid is opaque and absorbs and emits radiation in a manner that does not result in scattering. It is considered an unsteady laminar MHD convective rotating flow of heat-producing or absorbing second-grade fluid across a semi-infinite vertical moving permeable surface. The profiles of velocity components, temperature distribution, and concentration are studied to apply the regular perturbation technique. These profiles are shown as graphs for various fluid and geometric parameters such as Hall and ion slip parameters, radiation absorption, diffusion thermo, Prandtl number, Schmidt number, and chemical reaction rate. On the other hand, the skin friction coefficient and the Nusselt number are determined by numerical evaluation and provided in tables. These tables are then analysed and debated for various values of the flow parameters that regulate it. It may be deduced that an increase in the parameters of radiation absorption, Hall, and ion slip over the fluid region increases the velocity produced. The resulting momentum continually grows to a very high level, with contributions from the thermal and solutal buoyancy forces. The temperature distribution may be more concentrated by raising both the heat source parameter and the quantity of radiation. When one of the parameters for the chemical reaction is increased, the whole fluid area will experience a fall in concentration. Skin friction may be decreased by manipulating the rotation parameter, but the Hall effect and ion slip effect can worsen it. When the parameter for the chemical reaction increases, there is a concomitant rise in the mass transfer rate.

The event study model is a powerful econometric tool used for the purpose of estimating dynamic treatment effects. One of its most appealing features is that it provides a built-in graphical summary of results, which can reveal rich patterns of behavior. Another value of the picture is the estimated pre-event pseudo-\"effects\", which provide a type of placebo test. In this essay I aim to provide a framework for a shared understanding of these models. There are several (sometimes subtle) decisions and choices faced by users of these models, and I offer guidance for these decisions.

The “double-carbon” policy is a new opportunity for the transformation of China's production sector. With steady economic growth, each province has proposed specific policies aimed at cleaner production. However, the interactions between regions and the complex linkages between industries have hindered the implementation of the “double-carbon” policy. In order to address this issue, we introduced a complex network framework with multiple industries at a national level. The framework aimed to clarify whether there is fluctuation diffusion in China’s multi-province multi-industry carbon emission system, to identify key industries and regions, and to answer the question of “who” is the most effective in governance. The results showed that the fluctuations of industrial carbon emissions had a cross-regional diffusion effect in China indeed. The diffusion capacity of industry fluctuation depends on whether the industry is located at a “hub” position in the network. Hub industries with strong capacity can spread the carbon emission fluctuation of themselves and upstream or downstream industries to the whole country through regional interactions. This characteristic of the hub industry should be taken into account in governance to maximize the effectiveness of emission reduction. Shandong and Inner Mongolia, as important provinces for the production of intermediate products and energy chemicals in China, had a greater role to play in global carbon supply push from their hub industries than in the demand pull. The pulling capacity of Beijing-Tianjin-Hebei region to the national carbon demand side was greater than that of Yangtze River Delta and Pearl River Delta. These findings might have implications for environmental and economic policymaking, particularly with regard to cross-provincial coordinated systemic solutions and policy anchors for synergy with industries.

Shan, Q., 2020. The influence of trade agglomeration on technology diffusion in coastal cities in different time and space. In: Yang, Y.; Mi, C.; Zhao, L., and Lam, S. (eds.), Global Topics and New Trends in Coastal Research: Port, Coastal and Ocean Engineering. Journal of Coastal Research, Special Issue No. 103, pp. 543–547. Coconut Creek (Florida), ISSN 0749-0208. In order to realize the coordinated economic development of coastal cities, the influence of trade agglomeration on technology diffusion effect of coastal cities in different time and space is put forward. This paper analyzes the influence of main factors and technological factors on the diffusion effect of technology in coastal cities, and obtains the influence of internal factors of trade agglomeration on the diffusion effect of technology. Based on the analysis of economic environment and policy environment of city agglomeration, the influence of external factors of trade agglomeration on technology diffusion effect is obtained. The relationship between trade agglomeration and economic efficiency was tested by systematic GMM and panel regression. Trade agglomeration in each city has a significant promoting effect on scale efficiency, and has a significant difference on total factor productivity and other decomposition index. Therefore, some suggestions are put forward, such as taking the market as the core of the reform, strengthening the reform of the trade supply side, “moving from the virtual to the real”, promoting innovation-driven development and expanding trade opening.

Here’s why. (a) The Hodrick-Prescott (HP) filter introduces spurious dynamic relations that have no basis in the underlying data-generating process. (b) Filtered values at the end of the sample are very different from those in the middle and are also characterized by spurious dynamics. (c) A statistical formalization of the problem typically produces values for the smoothing parameter vastly at odds with common practice. (d) There is a better alternative. A regression of the variable at date t on the four most recent values as of date t − h achieves all the objectives sought by users of the HP filter with none of its drawbacks.

The development of organic solar cells (OSCs) with thick active layers is of crucial importance for the roll-to-roll printing of large-area solar panels. Unfortunately, increasing the active layer thickness usually results in a significant reduction in efficiency. Herein, we fabricated efficient thick-film OSCs with an active layer consisting of one polymer donor and two non-fullerene acceptors. The two acceptors were found to possess enlarged exciton diffusion length in the mixed phase, which is beneficial to exciton generation and dissociation. Additionally, layer by layer approach was employed to optimize the vertical phase separation. Benefiting from the synergetic effects of enlarged exciton diffusion length and graded vertical phase separation, an efficiency of 17.31% (certified value of 16.9%) is obtained for the 300 nm-thick OSC, with a short-circuit current density of 28.36 mA cm −2 , and a high fill factor of 73.0%. Moreover, the device with an active layer thickness of 500 nm also shows an efficiency of 15.21%. This work provides valuable insights into the fabrication of OSCs with thick active layers. Exciton diffusion length and graded vertical phase separation of the active layer play a critical role in the realization of high-performance thick-film organic solar cells (OSCs). Here, authors demonstrated OSCs with an efficiency of 17.31%, with an active layer thickness of around 300 nm.

The polarization and diffusion effects of landscape patterns are important features of megalopolis development. Under the urbanized effects, green space is a key spatial unit in delivering vital ecosystem services for sustainable urban planning. However, currently, fast urban developing is swamping the green space. In this study, by tracing landscape pattern changes of a fast-developing megalopolis, the Chengdu-Chongqing Megalopolis in the southeast of China, and using land-use data from 1980 to 2020, we aimed to determine the polarization and diffusion effects of the megalopolis and their impacts on the green space within and between the cities. We found that: (1) during the past four decades, spatial expansion of the megalopolis mainly occupied grassland and farmland, triggering an increase in landscape fragmentation; (2) based on socio-economic indicators, the spatial-attraction network analysis showed a significant polarization effect; however, based on the natural landscape, this analysis demonstrated a more scattered pattern; (3) importantly, the megalopolis developed at quite a similar pace, which caused the green rural area between the central cities demonstrating an encroached trend by the urbanization. To promote sustainability of the fast-developing megalopolis, we suggest that the boundary of the green space should be broadened to form a green network in which natural green space and urban green space are interconnected, improving the connectivity of habitats within the megalopolis for urban biodiversity. Our study implied that maintaining the green buffer shall be considered in advance for sustainable megaregional planning and establishing resilience of the fast-developing megalopolis.

Background After implementing a nationwide harm reduction program in 2006, a dramatic decline in the incidence of human immunodeficiency virus (HIV) infection among people with injection drug use (IDU) was observed in Taiwan. The harm reduction program might have sent out the message discouraging the choice of IDU among illicit drug users in early stage. Based on the yearly first-time offense rates from 2001 to 2017, this study aimed to examine (1) whether the nationwide implementation of the harm reduction program in 2006 led to changes in first-time offenders’ use of heroin; (2) whether the intervention had a similar effect on the use of other illicit drugs; and (3) whether the effect of the intervention was limited to the first-time offenders of young age groups. Methods Yearly first-time illicit-drug offense rates from 2001 to 2017 in Taiwan were derived from two national databases for drug arrests that were verified using urine tests: the Criminal Record Processing System on Schedule I/II Drugs and the Administrative Penalty System for Schedule III/IV Substances. A hierarchy of mutually exclusive categories of drug uses was defined by the drug with the highest schedule level among those tested positive in an arrest. Segmented regression analyses of interrupted time series were used to test for the impact of the 2006 intervention. Results There was a decrease of 22.37 per 100,000 in the rate for heroin but no detectable level changes in that for methamphetamine or ecstasy after the 2006 intervention in Taiwan. There were baseline decreasing trends in the first-time offense rate from 2001 to 2017 for heroin and ecstasy and an increasing trend for methamphetamine, with the slopes not altered by the 2006 intervention. The postintervention decrease in the first-time offense rate for heroin was detectable among offenders less than 40 years old. Conclusions Our results indicate a diffusion effect of the 2006 intervention on decreasing heroin use among young offenders and have policy implications for better prevention and treatment for different age groups.

In the recent literature, many research studies have proven that Known and Chosen plaintext attacks are very efficient tools that are widely used to cryptanalyze partially or completely some chaos-based and non-chaos cryptosystems. In this paper, we addressed some weaknesses in the first Zhang et al., cryptosystem “An image encryption scheme using reverse 2-dimensional chaotic map and dependent diffusion”. First, we analyzed the encryption process of Zhang et al., and we found that the non-linear diffusion process can be removed because its argument is present in the ciphered image. Then, based on this observation we derived a partial cryptanalysis equation that removes the effect of the diffusion function and accordingly permits to recover the permuted version of the ciphered image. As a result of the previous operation, the brute-force attack became more suitable. In addition, we mounted a chosen plaintext attack based on a proposed chosen plain image. Consequently, the encryption key space is reduced or recovered for one round, also, the average values of NPCR and UCAI randomness parameters become small compared to the optimal values, and moreover, they are very low for specific pixel position attacks.