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Definition: In response to the increasing complexity and sophistication of cyber threats, particularly those enhanced by advancements in artificial intelligence, traditional security methods are proving insufficient. This paper provides an overview of the zero-trust cybersecurity framework, which operates on the principle of "never trust, always verify" to mitigate vulnerabilities within organizations. Specifically, this paper examines the applicability of zero-trust principles in environments where large volumes of information are exchanged, such as schools and libraries, highlighting the importance of continuous authentication (proving who users are within the network), least privilege access (providing only access to what users specifically need), and breach assumption (assuming a breach has or will occur and thus operating to limit the spread through the use of multiple checkpoints throughout the network). The analysis highlights avenues for future research that may help preserve the security of vulnerable organizations. [ABSTRACT FROM AUTHOR]

In this study, the response surface method is used to develop a model for analyzing and optimizing zinc leaching experiments. An investigation into the leaching kinetics of smithsonite in ammonium citrate solution is also conducted. A model of kinetics is studied in order to represent these effects. The experimental data show that an increase in the solution temperature, concentration, and stirring speed has a positive impact on the leaching rate, while an increase in the particle size has a negative impact on it. The optimal experimental conditions consist of a leaching temperature of 70 °C, ammonium citrate concentration of 5 mol/L, particle size of 38 µm, and rotational speed of 1000 rpm. Under these optimal conditions, the leaching rate of zinc from smithsonite is 83.51%. It is speculated that the kinetic model will change when the temperature is higher than 60 °C. When the temperature is lower than 60 °C, the leaching process is under the control of the shrinking core model of the surface chemical reactions. The calculated activation energy of the leaching reaction is equal to 42 kJ/mol. The model of the leaching process can be described by the following equation: 1 − 1 − x 1 / 3 = k 0 ⋅ (C) 0.6181 ⋅ r 0 − 0.5868 ⋅ S S 0.6901 exp ⁡ − 42 / R T ] t . This demonstrates that an ammonium citrate solution can be used in the leaching process of zinc in smithsonite as an effective and clean leaching agent. [ABSTRACT FROM AUTHOR]

Valuing the nonuse value of a national forest park (NFP) is critically important to obtain a better understanding of its total economic value, beyond focusing solely on the recreation value. This paper estimates the nonuse value of an NFP based on the relationship between the local public's environmental attitudes and their willingness to pay (WTP). The data collected on the local residents' environmental attitudes relied on the New Ecological Paradigm (NEP). Residents' willingness to pay (WTP) for the national forest parkland protection was collected using the contingent valuation method (CVM). The nonuse value WTP was estimated using a bivariate dichotomous choice model. This model analyzed the relationship between the environmental attitude scores and WTP in order to estimate the nonuse value of the NFP of our case study site, Dalian Xijiao National Forest Park (DXNFP) in northeastern China. The results showed that DXNFP provides 20.26 CNY (3.02 USD) in nonuse value per household per year in Dalian city, which can then be translated into 140 CNY (21 USD) million annually in total. [ABSTRACT FROM AUTHOR]

Featured Application: The options for the treatment of K-Ras-driven lung tumors are currently limited. This study investigates the potential for non-thermal intervention against lung tumors using magnetic nanoparticles (MNPs) in a magnetic field. The MNPs for use in treating tumors were prepared by chemical methods. Simulations showed that the experimental platform can generate the desired magnetic field by avoiding any damaging rise in temperature and that the induced magnetic force can affect the cellular activities. Using MNPs in a magnetic field in this way can not only suppress the growth of tumor cells but also can strengthen the inhibitory effects of magnetic field stimulation on the lung tumors caused by the K-Ras mutations. K-Ras mutations result in normal cells dividing uncontrollably and becoming cancerous. The prognosis is currently poor for patients due to the lack of drugs that can effectively target these mutations. In this study, magnetic nanoparticles (MNPs) were prepared, characterized, and cooperated with a magnetic field to intervene in the growth of lung tumor cells. The rise in temperature of a stimulation coil was studied by numerical calculation. The non-thermal effects of MNPs under a magnetic force were analyzed. The cell experiments showed that the growth of A549 tumor cells slowed down. The result of a wound-healing assay also indicated that the migration of tumor cells was suppressed. Compared with magnetic stimulation without MNPs, MNPs enhanced the inhibitory effects of a magnetic field. This study suggests a new way to treat K-Ras driven lung tumors using non-thermal effects of MNPs without the side effects caused by thermal effects. [ABSTRACT FROM AUTHOR]

Featured Application: Since magnetic stimulation can activate brain tissue with optimum intensity and frequency, it demonstrates great potential for many medical applications, procedures, and treatments. For example, it makes it easier to reach a deeper region beneath the skin without causing any trauma or pain. In addition, magnetic stimulation does not leave any residues in the operated tissues. However, the magnetic fields generated by typical and conventional coils are uniform around their targets, and their magnetic stimulation performance still needs improvement. Thus, an innovative coil that has a quad coil form was proposed for transcranial magnetic stimulation, which makes it possible to shrink the irritative zone and strengthen the stimulation intensity, thus achieving higher magnetic stimulation performance. Previous research showed that pulsed functional magnetic stimulation can activate brain tissue with optimum intensity and frequency. Conventional stimulation coils are always set as a figure-8 type or Helmholtz. However, the magnetic fields generated by these coils are uniform around the target, and their magnetic stimulation performance still needs improvement. In this paper, a novel type of stimulation coil is proposed to shrink the irritative zone and strengthen the stimulation intensity. Furthermore, the electromagnetic field distribution is calculated and measured. Based on numerical simulations, the proposed coil is compared to traditional coil types. Moreover, the influential factors, such as the diameter and the intersection angle, are also analyzed. It was demonstrated that the proposed coil has a better performance in comparison with the figure-8 coil. Thus, this work suggests a new way to design stimulation coils for transcranial magnetic stimulation. [ABSTRACT FROM AUTHOR]

In the field of cold bending, it is necessary to use ball mandrels, especially to bend thin-walled tubes with a small radius. However, the bending process with a ball mandrel is complex and expensive, and it is easy to jam the core ball inside the tube. To solve these issues, we designed two kinds of hollow non-ball mandrel schemes with low stiffness that were suitable for the small radius bending of thin-walled tubes. We evaluated the forming quality of cold bending numerically and the influence of the hollow section length and thickness on the forming indices. Our results showed that the thickness of the hollow section has a greater influence on forming quality than the length. As the hollow section's thickness increased, the wrinkling rate first declined by approximately 40% and then increased by above 50%. When the thickness was 11 mm in scheme 1 and 13 mm in scheme 2, the wrinkling rate reached minimum values of 1.32% and 1.50%, respectively. As the hollow section's thickness increased, the flattening rate decreased by more than 60% and the thinning rate increased by about 40%. A multi-objective optimization of forming indices was carried out by ideal point method and grey wolf optimizer. By comparing the forming results before and after optimization, the feasibility of using the proposed hollow mandrel was proved, and the hollow mandrel scheme of standard cylinder is therefore recommended. [ABSTRACT FROM AUTHOR]

Angular momentums (AMs) of photons are crucial physical properties exploited in many fields such as optical communication, optical imaging, and quantum information processing. However, the active manipulation (generation, switching, and conversion) of AMs of light on a photonic chip remains a challenge. Here, we propose and numerically demonstrate a reconfigurable graphene-based hybrid plasmonic waveguide (GHPW) with multiple functions for on-chip AMs manipulation. Its physical mechanism lies in creating a switchable phase delay of ±π/2 between the two orthogonal and decomposed linear-polarized waveguide modes and the spin-orbit coupling in the GHPW. For the linear-polarized input light with a fixed polarization angle of 45°, we can simultaneously switch the chirality (with −ħ/+ħ) of the transverse component and the spirality (topological charge ℓ = −1/+1) of the longitudinal component of the output terahertz (THz) light. With a switchable phase delay of ±π in the GHPW, we also developed the function of simultaneous conversion of the charity and spirality for the circular-polarized input light. In addition, a selective linear polarization filtering with a high extinction ratio can be realized. With the above multiple functions, our proposed GHPWs are a promising platform in AMs generation, switching, conversion, and polarization filtering, which will greatly expand its applications in the THz photonic integrated circuits. [ABSTRACT FROM AUTHOR]