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The oriental armyworm, Mythimna separata (Walker), is a highly migratory pest known for its sudden larval outbreaks, which result in severe crop losses. These unpredictable surges pose significant challenges for timely and accurate monitoring, as conventional methods are labour-intensive and prone to errors. To address these limitations, this study investigates the use of machine learning for automated and precise identification of M. separata larval instars. A total of 1577 larval images representing different instar were analysed for geometric, colour, and texture features. Additionally, larval weight was predicted using 13 regression models. Instar identification was conducted using Support Vector Classifier (SVC), Random Forest, and Multi-Layer Perceptron. Key feature contributing to classification accuracy were subsequently identified through permutation feature importance analysis. The results demonstrated the potential of machine learning for automating instar identification with high efficiency and accuracy. Predicted larval weight emerged as a key feature, significantly enhancing the performance of all identification models. Among the tested approaches, BaggingRegressor exhibited the best performance for larval weight prediction (R2 = 98.20%, RMSE = 0.2313), while SVC achieved the highest instar identification accuracy (94%). Overall, the integration of larval weight with other image-derived features proved to be a highly effective strategy. This study demonstrates the efficacy of machine learning in enhancing pest monitoring systems by providing a scalable and reliable framework for precise pest management. The proposed methodology significantly improves larval instar identification accuracy and efficiency, offering actionable insights for implementing targeted biological and chemical control strategies.
This case study provides a comprehensive analysis of the intricate political risks faced by TikTok, the Chinese social media giant, within the complex US political landscape. Beginning with an exploration of the security concerns articulated by the US government, the discussion centers on TikTok’s data collection practices and their perceived impact on US national security. The narrative unfolds by elucidating the multifaceted strategies employed by TikTok and its parent company, ByteDance, to address these challenges, including litigation, endeavors toward Americanization, and technological adaptations. It also examines the evolution in the US government’s stance as well as TikTok’s adaptive strategies aimed at sustaining and expanding its presence in the US market. The study depicts the responses of the Chinese government to US policies, unraveling the broader implications of these developments on the global political-economic landscape, exploring the dynamics involved in US-China relations, and providing a deeper understanding of the complexities inherent in such interactions. Finally, this case study invites readers to engage in contemplation on the broader themes of political risks faced by multinational corporations, the challenges inherent in navigating global legal frontiers, and the intricate nature of US-China relations.
The emotion regulation network (ERN) in the brain provides a framework for understanding the neuropathology of affective disorders. Although previous neuroimaging studies have investigated the neurobiological correlates of the ERN in major depressive disorder (MDD), whether patients with MDD exhibit abnormal functional connectivity (FC) patterns in the ERN and whether the abnormal FC in the ERN can serve as a therapeutic response signature remain unclear.
Methods
A large functional magnetic resonance imaging dataset comprising 709 patients with MDD and 725 healthy controls (HCs) recruited across five sites was analyzed. Using a seed-based FC approach, we first investigated the group differences in whole-brain resting-state FC of the 14 ERN seeds between participants with and without MDD. Furthermore, an independent sample (45 MDD patients) was used to evaluate the relationship between the aforementioned abnormal FC in the ERN and symptom improvement after 8 weeks of antidepressant monotherapy.
Results
Compared to the HCs, patients with MDD exhibited aberrant FC between 7 ERN seeds and several cortical and subcortical areas, including the bilateral middle temporal gyrus, bilateral occipital gyrus, right thalamus, calcarine cortex, middle frontal gyrus, and the bilateral superior temporal gyrus. In an independent sample, these aberrant FCs in the ERN were negatively correlated with the reduction rate of the HAMD17 score among MDD patients.
Conclusions
These results might extend our understanding of the neurobiological underpinnings underlying unadaptable or inflexible emotional processing in MDD patients and help to elucidate the mechanisms of therapeutic response.
We establish hyperweak boundedness of area functions, square functions, maximal operators, and Calderón–Zygmund operators on products of two stratified Lie groups.
Broadband frequency-tripling pulses with high energy are attractive for scientific research, such as inertial confinement fusion, but are difficult to scale up. Third-harmonic generation via nonlinear frequency conversion, however, remains a trade-off between bandwidth and conversion efficiency. Based on gradient deuterium deuterated potassium dihydrogen phosphate (KDxH2-xPO4, DKDP) crystal, here we report the generation of frequency-tripling pulses by rapid adiabatic passage with a low-coherence laser driver facility. The efficiency dependence on the phase-matching angle in a Type-II configuration is studied. We attained an output at 352 nm with a bandwidth of 4.4 THz and an efficiency of 36%. These results, to the best of our knowledge, represent the first experimental demonstration of gradient deuterium DKDP crystal in obtaining frequency-tripling pulses. Our research paves a new way for developing high-efficiency, large-bandwidth frequency-tripling technology.
The rule of law, an abstract concept heavily debated among legal scholars and social scientists, has in the past few decades acquired a nearly universal appeal, as democracies, autocracies, and oligarchies all claim to uphold it. Repeatedly, Xi and the leaders of the Chinese Communist Party (CCP) have pledged to build a “rule-of-law country.” But when the ruling elites of a one-party authoritarian state allege commitment to the rule of law, what do they really mean? How is it different from the Western concepts of the rule of law, especially the “thick” version of it that has been closely tied to liberal democratic values? What are the key features of the “rule of law with Chinese characteristics”? And how will it impact the international legal order? Applying a transnational legal ordering framework, this chapter attempts some answers. It traces the development of the Chinese legal system and the evolving rule-of-law debates in China and then explores how China might impact the international legal order.
The effects of the evolution of vortices on the aeroacoustics generated by a hovering wing are numerically investigated by using a hybrid method of an immersed boundary–finite difference method for the three-dimensional incompressible flows and a simplified model based on the Ffowcs Williams-Hawkings acoustic analogy. A low-aspect-ratio ($AR=1.5$) rectangular wing at low Reynolds ($Re=1000$) and Mach ($M=0.04$) numbers is investigated. Based on the simplified model, the far-field acoustics is shown to be dominated by the time derivative of the pressure on the wing surface. Results show that vortical structure evolution in the flow fields, which is described by the divergence of the convection term of the incompressible Navier–Stokes equations in a body-fixed reference frame, determines the time derivative of the surface pressure and effectively the far-field acoustics. It dominates over the centrifugal acceleration and Coriolis acceleration terms in determining the time derivative of the surface pressure. The position of the vortex is also found to affect the time derivative of the surface pressure. A scaling analysis reveals that the vortex acoustic source is scaled with the cube of the flapping frequency.
Liquid droplet dynamics are widely used in biological and engineering applications, which contain complex interfacial instabilities and pattern formation such as droplet merging, splitting and transport. This paper studies a class of mean field control formulations for these droplet dynamics, which can be used to control and manipulate droplets in applications. We first formulate the droplet dynamics as gradient flows of free energies in modified optimal transport metrics with nonlinear mobilities. We then design an optimal control problem for these gradient flows. As an example, a lubrication equation for a thin volatile liquid film laden with an active suspension is developed, with control achieved through its activity field. Lastly, we apply the primal–dual hybrid gradient algorithm with high-order finite-element methods to simulate the proposed mean field control problems. Numerical examples, including droplet formation, bead-up/spreading, transport, and merging/splitting on a two-dimensional spatial domain, demonstrate the effectiveness of the proposed mean field control mechanism.
Thin-film beam combining technology is an effective approach to improve output power while maintaining beam quality. However, the lack of comprehensive research into the key factors affecting the beam quality in systems makes it challenging to achieve a practical combined beam source with high brightness. This paper clearly established that the temperature rise of dichroic mirrors (DMs) and sub-beam overlapping precision are the main factors affecting the beam quality of the system, with quantified effects. Based on this understanding, a combined light source of four channels of 3 kW fiber lasers was achieved, and an output power of 11.4 kW with a beam quality of M2x = 1.601 and M2y = 1.558, using three high-steepness low-absorption DMs and the active control technique. To the best of our knowledge, this is the best beam quality for a 10 kW light source. This study offers a solution for practical high-power laser sources in the tens of kilowatts range.
Wall temperature has a significant effect on shock wave/turbulent boundary layer interactions (STBLIs) and has become a non-negligible factor in the design process of hypersonic vehicles. In this paper, direct numerical simulations are conducted to investigate the wall temperature effects on STBLIs over a 34° compression ramp at Mach number 6. Three values of the wall-to-recovery-temperature ratio (0.50, 0.75 and 1.0) are considered in the simulations. The results show that the size of the separation bubble declines significantly as the wall temperature decreases. This is because the momentum profile of the boundary layer becomes fuller with wall cooling, which means the near-wall fluid has a greater momentum to suppress flow separation. An equation based on the free-interaction theory is proposed to predict the distributions of the wall pressure upstream of the corner at different wall temperatures. The prediction results are generally consistent with the simulation results (Reynolds number Reτ ranges from 160 to 675). In addition, the low-frequency unsteadiness is studied through the weighted power spectral density of the wall pressure and the correlation between the upstream and downstream. The results indicate that the low-frequency motion of the separation shock is mainly driven by the downstream mechanism and that wall cooling can significantly suppress the low-frequency unsteadiness, including the strength and streamwise range of the low-frequency motions.
Most US lawsuits involving Chinese companies are initiated by or against their customers, employees, or business counterparts. However, on occasion, Chinese investors may go to court against a US government entity to resolve a dispute. As US–China relations continue to deteriorate, Chinese companies are increasingly caught in the crossfire of the geopolitical rivalry. Being suspected as agents for the Chinese state, China-headquartered multinational companies, especially those with ties to the Chinese government, have expressed growing frustration over what they perceive as unfair treatment by the US government. This chapter examines the legal reactions of Chinese companies to perceived official bias in the United States in the context of intensifying geopolitical tensions.
The US legal system is notoriously complex. Navigating this labyrinthine structure requires knowledge of legal precedents, procedures, and rules, along with the ability to anticipate and adapt to shifts in the legal landscape. Businesses, therefore, require the guidance of seasoned lawyers. Over the past few decades, US corporations have increasingly turned to in-house lawyers for legal services, leading to their rising prominence in the corporate hierarchy and profound changes in the US legal profession and corporate governance. This could also be true for Chinese companies operating in the United States. Hence, this chapter investigates the Chinese companies’ utilization of full-time internal legal managers within the dual institutional context. For those employing such managers, this chapter scrutinizes two key aspects: (1) whether these legal managers are locally hired or are expatriates and (2) whether they hold licenses to practice law in the United States, which approximates their ability to handle US legal risks and opportunities. Analysis under the dual institutional framework reveals not only effects of both home- and host-state institutions but also substantial intercompany variations associated with other institutional and firm-specific variables of theoretical and policy importance.
After decades of exponential growth, China has transformed from a stagnant, impoverished autarky to the world’s second-largest economy highly integrated into global supply chains, and numerous Chinese firms have embarked on overseas business expansion on an unprecedented scale. Against that backdrop, many Chinese investors have ventured into the highly competitive, strategically important US market. Though the recent geopolitical confrontation between the two countries has hampered the investment flow, many large Chinese investors have been hesitant to withdraw from the US market. How do Chinese investors negotiate the omnipresent and consequential legal risks and opportunities in the United States? This question, which holds great practical, policy, and theoretical importance, has received scant scholarly attention. This chapter lays out the road map of the book that attempts to provide the answers.
With or without professional in-house counsel, Chinese companies must rely heavily on outside lawyers to effectively manage legal risks in the United States. Companies operating in the United States must navigate through an intricate web of legal rights and obligations, which cannot be done without adequate legal assistance. While a vast literature has accumulated on the US legal profession and the legal service market, few scholars have studied the interactions between multinational companies and their US lawyers, leaving important questions open. For instance, do Chinese companies bring their lack of appreciation or even contempt for lawyers and legal services to the United States, or do they adapt to the host-state environment and take legal advice seriously? Moreover, how do Chinese companies choose from the 1.3 million US lawyers? Are Chinese companies becoming a significant revenue source for US law firms, which will give them pricing power in the market and the ability to dictate how legal services are provided? Do their lawyer selection preferences and legal expenditures vary across different Chinese companies, and if so, what institutional and firm-specific factors may explain the variations? This chapter answers these crucial yet unexplored questions within the dual institutional framework.
To litigate or not to litigate, that is the question any Chinese companies operating in the United States long enough must contemplate. For American companies, litigation is nothing but an unavoidable business risk and often a vital competition strategy, routinely dealt with by legal and managerial professionals applying monetarized cost–benefit analysis. Such analysis typically incorporates attorney fees and other litigation expenses, potential reputational damage, time and human resource consumption, and the present value of expected litigation gains or losses. By contrast, litigation in China carries complex social meanings and is often avoided to preserve long-term cooperative relationships or to signal desirable attributes to uninformed third parties. When lawsuits do occur, they are often handled by stakeholders without professional legal assistance. Disputants consider a wide range of material and nonmaterial interests that are shaped by both formal institutions undergoing significant transformation and complex, entrenched social norms governing dispute resolution. Chinese companies immersed in these two disparate institutional environments approach legal disputes in the United States.
In China, corporate management and business transactions often relegate the legal system to a more peripheral role. Chinese companies then encounter formidable institutional obstacles when operating in developed countries with robust, strict, and complex legal systems. Obviously, nowhere else are the hurdles as high as in the United States. How then do Chinese investors negotiate the omnipresent legal risks? This chapter begins with an overview of China’s outbound direct investment in the United States. It then introduces research questions ranging from the role of in-house legal counsel in Chinese companies to their legal responses to unfair treatment by the US government. Next, this chapter selectively summarizes and critically reviews the existing literature pertinent to the interactions between multinational companies and the complex US legal system. From this, I formulate a comprehensive theoretical framework predicated on dual institutional influence, which will be applied consistently throughout the book. The chapter concludes with a description of the research methodology.