State Response Research Articles

Interaction mechanisms of urban ecosystem resilience based on pressure-state-response framework: A case study of the Yangtze River Delta

The unprecedented pace of urbanization has intensified environmental concerns, underscoring the critical importance of bolstering urban ecosystem resilience (UER) in contemporary cities. This study presents a Pressure–State–Response framework for evaluating the UER within the Yangtze River Delta region spanning 2012 to 2021. Utilizing spatial visualization techniques and the panel vector auto–regressive model, spatial differentiation patterns and interaction mechanisms among sub–dimensions are examined. Findings indicate an overall positive trajectory of UER, characterized by decreasing Pressure, noteworthy steady growth in State, and rising Response. Spatially, Pressure is higher in the north and lower in the south, with large cities becoming new centers of high pressure; State is higher in the southwest mountains and lower in the northeast plains; Responses center around Shanghai, expanding toward the southwest and northwest. The complex interactions between Pressure, State, and Response form a nested cycle of UER, indicating that the UER in the Yangtze River Delta is evolving towards a more rational development trend, where the tight mechanism of societal Response plays a key role. The implications underscore the urgent need for tailored regional governance strategies that leverage spatial variations, balance human impact on ecosystems, and optimize dimensional interactions for resilient city development. This research contributes a comprehensive framework for understanding and enhancing ecological resilience in the Yangtze River Delta region, offering valuable insights into regional governance and long–term urban ecological sustainability amidst global environmental challenges.

Unveiling chiral states in the XXZ chain: finite-size scaling probing symmetry-enriched c = 1 conformal field theories

We study the low-energy properties of the one-dimensional spin-1/2 XXZ chain with time-reversal symmetry-breaking pseudo-scalar chiral interaction and propose a phase diagram for the model. In the integrable case of the isotropic Heisenberg model with the chiral interaction, we employ the thermodynamic Bethe ansatz to find “chiralization”, the response of the ground state versus the strength of the pseudo-scalar chiral interaction of a chiral Heisenberg chain. Unlike the magnetization case, the chirality of the ground state remains zero until the transition point corresponding to critical coupling αc = 2J/π with J being the antiferromagnetic spin-exchange interaction. The central-charge c = 1 conformal field theories (CFTs) describe the two phases with zero and finite chirality. We show for this particular case and conjecture more generally for similar phase transitions that the difference between two emergent CFTs with identical central charges lies in the symmetry of their ground state (lightest weight) primary fields, i.e., the two phases are symmetry-enriched CFTs. At finite but small temperatures, the non-chiral Heisenberg phase acquires a finite chirality that scales with the temperature quadratically. We show that the finite-size effect around the transition point probes the transition.

A new adaptive droop control strategy for improved power sharing accuracy and voltage restoration in a DC microgrid

In a DC Microgrid, accurate power sharing and voltage restoration are two primary control goals to guarantee power quality and reliable operation. Inaccurate power sharing is a significant concern due to discrepancies in feeder line resistance, faulty equipment, lack of monitoring and control, and nonlinear load. Moreover, inaccurate power sharing may lead to overloading of converters and cause a cascade of failures throughout the entire system. This study proposes a new adaptive droop control strategy to address these challenges. To enhance accurate power sharing, error current sharing is formulated by considering bus current and total rated current. This is regulated by the adaptive controller to adjust droop resistance. Additionally, the impact of droop voltage because of feeder line resistance is considered in the proposed strategy. The primary control loop regulates the output voltage of converter utilizing the proposed observer-based optimum sliding mode control (OOSMC). The controller gain of the OOSMC is optimized using a gradient-based method to enhance transient and steady state response of the converter output. In the secondary loop, the twin-delayed deep deterministic policy gradient (TD3) for voltage restoration is employed with a new reward function to optimally tune the proportional-integral (PI) controller. Finally, the superiority of the proposed strategy is evaluated through rigorous testing scenarios, including the use of constant power load (CPL) and sudden failure in the converters. Moreover, the proposed strategy is validated by simulations and laboratory-based experiments. The results show that the OOSMC outperforms GA and PSO while the TD3 has better performance than traditional PI. Furthermore, when the equivalent power-rated converters are implemented in the system, the proposed strategy can transfer identical power sharing of 4 W to the load and provide accurate current sharing of 0.167 A compared to conventional droop control while the DC bus voltage is maintained at the 24 V reference value. In the case of different power-rated converters, the proposed strategy can achieve power sharing accuracy. The first, second and third converters supply 2 W, 4 W, and 6 W, respectively, to the load and provide accurate current sharing. Meanwhile the DC bus voltage can be kept at the reference voltage of 24 V. In the scenario of various kinds of disturbances, the proposed strategy can achieve accurate power and current sharing when the system is tested under load and input voltage variations. Meanwhile the DC bus voltage always returns to the voltage reference. Moreover, the proposed strategy can share power and current accurately when the converter occurs a sudden failure.

Reflections on Coastal State Response Options in an Era of Sea Level Rise: Practical Challenges and Legal Consequences

Abstract This contribution to the Reflections section of Ocean Yearbook devoted to the memory of the late Professor Meinhard Doelle concerns the options available to coastal States in their responses to global sea level rise driven by anthropogenic climate change. These reflections seek to explore the main policy options and practical approaches based on physical interventions in this context and to assess the possible risks as well as benefits of those approaches. They also explore some of the more radical and cutting-edge technologies which are already being deployed. While addressing the physical intervention options and some of their practical and legal implications, this paper also addresses the importance of environmental impact assessments (EIAs) and capacity-building, both of which were key themes in Meinhard Doelle’s work.

Click train elicited local gamma synchrony: differing performance and pharmacological responsivity of primary auditory and prefrontal cortices

Auditory neural networks in the brain naturally entrain to rhythmic stimuli. Such synchronization is an accessible index of local network performance as captured by EEG. Across species, click trains delivered ∼ 40 Hz show strong entrainment with primary auditory cortex (Actx) being a principal source. Imaging studies have revealed additional cortical sources, but it is unclear if they are functionally distinct. Since auditory processing evolves hierarchically, we hypothesized that local synchrony would differ between between primary and association cortices. In female SD rats (N = 12), we recorded 40 Hz click train-elicited gamma oscillations using epidural electrodes situated at two distinct sites; one above the prefrontal cortex (PFC) and another above the Actx, after dosing with saline (1 ml/kg, sc) or the NMDA antagonist, MK801 (0.025, 0.05 or 0.1 mpk), in a blocked crossover design. Post-saline, both regions showed a strong 40 Hz auditory steady state response (ASSR). The latencies for the N1 response were ∼ 16 ms (Actx) and ∼ 34 ms (PFC). Narrow band (38–42 Hz) gamma oscillations appeared rapidly (<40 ms from stim onset at Actx but in a more delayed fashion (∼200 ms) at PFC. MK801 augmented gamma synchrony at Actx while dose-dependently disrupting at the PFC. Event-related gamma (but not beta) coherence, an index of long-distance connectivity, was disrupted by MK801. In conclusion, local network gamma synchrony in a higher order association cortex performs differently from that of the primary auditory cortex. We discuss these findings in the context of evolving sound processing across the cortical hierarchy.

A content analysis of legal policy responses to xylazine in the illicit drug supply in the United States

BackgroundXylazine is a veterinary sedative that is quickly spreading in the U.S. illicit drug supply and is increasingly associated with fatal overdoses and severe wounds. In response, xylazine has been deemed an emerging public health threat and several policy initiatives have been introduced to combat its spread and negative broad health impact. We aimed to synthesize trends in all-time U.S. policy responses to xylazine in the drug supply. MethodsIn April 2024, we systematically identified and categorized proposed and enacted policy initiatives that related to human xylazine consumption by searching LexisNexis and Thomas Reuters Westlaw legal databases. ResultsOf 58 unique policy initiatives, most were introduced in 2023 (n = 37/58, 64 %) and concentrated in Northeastern states. Penalties for xylazine possession, often tied to state drug scheduling changes, were the most common provision (n = 34/58; 59 %) and Schedule III was the most frequently proposed scheduling level (n = 17/30; 57 %). Other provisions included proposals to enhance: test strip access (n = 11/58; 19 %), public awareness and education (n = 3/58; 5 %), xylazine-specific research (n = 4/58; 7 %), and surveillance (n = 8/58; 14 %). ConclusionU.S. state and federal policy responses to xylazine grew rapidly in 2023, were most concentrated in states affected most by xylazine, and scheduling was the most commonly proposed policy approach. Research measuring policy effects should be prioritized as policies are implemented.

Thermodynamic Response and Neutral Excitations in Integer and Fractional Quantum Anomalous Hall States Emerging from Correlated Flat Bands.

Integer and fractional Chern insulators have been extensively explored in correlated flat band models. Recently, the prediction and experimental observation of fractional quantum anomalous Hall (FQAH) states with spontaneous time-reversal symmetry breaking have garnered attention. While the thermodynamics of integer quantum anomalous Hall (IQAH) states have been systematically studied, our theoretical knowledge on thermodynamic properties of FQAH states has been severely limited. Here, we delve into the general thermodynamic response and collective excitations of both IQAH and FQAH states within the paradigmatic flat Chern-band model with remote band considered. Our key findings include (i)in both ν=1 IQAH and ν=1/3 FQAH states, even without spin fluctuations, the charge-neutral collective excitations would lower the onset temperature of these topological states, to a value significantly smaller than the charge gap, due to band mixing and multiparticle scattering; (ii)by employing large-scale thermodynamic simulations in FQAH states in the presence of strong interband mixing between C=±1 bands, we find that the lowest collective excitations manifest as the zero-momentum excitons in the IQAH state, whereas in the FQAH state, they take the form of magnetorotons with finite momentum; (iii)the unique charge oscillations in FQAH states are exhibited with distinct experimental signatures, which we propose to detect in future experiments.

Interval uncertainty-oriented impedance force control for space manipulator with time-dependent reliability

For specific missions of spacecraft including on-orbit assembly, docking, grasp, etc., the presence of uncertainties leads to difficulties in the analysis of impedance force control systems and evaluations of safety for space manipulators. Therefore, in this study, a novel interval uncertainty-oriented impedance force control method for space manipulators with time-dependent reliability was established. The proposed method can accurately and rapidly characterize uncertainties. Additionally, it can reflect the reliability of a control system based on an overall time history. Once the uncertainties of the dynamic models and state responses are known, their uncertainty bounds can be obtained using an established non-probabilistic propagation method with high accuracy. An interval process model and the first passage theory are employed in the non-probabilistic time-dependent model. A joint reliability index is established based on the single reliability indexes, which can more efficiently evaluate the control system reliability than the individual indexes. A numerical example related to space manipulator is used to study the developed impedance force control method and verify the effectiveness of the method. The results from the response curves reveal validity of the proposed method, while the reduction in time proves efficiency of the method.

Analysis of the mutability of the legal framework for migration policy in Russia (1990-2023) in the context of the effectiveness of migration governance

The article analyzes the dynamics of changes in the institutional and legal framework of Russian migration policy from 1990 to 2023. Based on legal statistics, the authors investigate the frequency of amendments to key laws in the field of migration regulation in the Russian Federation. By comparing the series of events in political, legal, and institutional changes to migration governance, the authors identify external factors that influence the changes in legislation. Through comparative legal methods and an analysis of relevant literature, we discuss issues related to the differences between adaptive governance and agile management, as well as the impact of rapidly changing laws on the stability of the legal system. The analysis of the data revealed a high frequency of changes to migration laws, with an average of up to 5-6 amendments per year, and in some cases, up to 15-17 amendments per year. Acts of federal and regional authorities are also frequently amended. During the pandemic, a decision of the Moscow government was in effect for a little over a week. There is a significant excess in the number of secondary legal acts compared to the number of primary ones. The constant amendment of migration regulations reflects the state's response to diverse and sometimes unforeseen challenges in modern society, and demonstrates the adaptive nature of Russia's migration policy. This increase in adaptability raises questions about where the line is between improving the efficiency of legal regulations and their instability. Additionally, a special multidisciplinary approach is required to assess how changes in migration policies affect socio-economic development. The relevance of this study is linked to the fact that improving the efficiency of migration governance is a challenging task. Migration is both a source of economic development and potential risk to socio-political stability.

Static response of wind turbine blades: Comparison of low- and high-fidelity numerical models

As wind turbine blades become longer and more flexible, the structural models employed in current aeroelastic simulation tools, usually based on beam formulations, are challenged. Effects previously considered negligible in the response of these beam-like structures might now become significant to obtain accurate predictions of their behaviour. To assess this, a test matrix covering key geometric and material characteristics of wind turbine blades is defined and three test cases are analysed as an initial stage of this study. For each case, the static deflection of the beam model from the aeroelastic tool HAWC2 is compared against higher-fidelity shell/solid finite element models. Three structures are studied: an isotropic box beam, a composite box beam and a 12.6 m wind turbine blade from DTU. A good match is observed for the box beam test cases, which study the effects of out-of-plane and distortion warping and bend-twist coupling. Important aspects of high-fidelity models (such as end effects) are highlighted. The study of the DTU 12.6 m blade shows a significant difference (15%) in the torsion natural frequencies of the beam model, though a good agreement in twist angle under torsional loading. More pronounced differences in twist angle are observed when a load distribution based on the steady state response is applied, likely resulting from challenges in modelling complex structural features and three-dimensional effects.

Defect test of substation grounding grid based on impulse response

Abstract The substation grounding grid has been in the open air for a long time, and it is prone to problems such as fracture and desoldering, which leads to a decrease in grounding capacity and becomes a threatening factor affecting the normal operation of the substation. Based on the principle of state response, this paper demonstrates the feasibility of using impulse current to evaluate the defects of the grounding grid, constructs an impulse impedance test system, and conducts defect detection tests on 8 m×8 m (2 m equal intervals) and 28 m×25 m (unequal interval) grounding grids in the laboratory. It analyzes the measured impulse impedance and amplitude-frequency response curves. After testing the grounding grid of a substation of a power grid company, the test results show that the test system based on the principle of state response is effective. The response voltage waveform and amplitude-frequency response curve when detecting the conductor fracture of the grounding grid are different from the waveform curve when there is no defect. It can be applied to the defect evaluation of the grounding grid and has a certain reference value for practical engineering applications.

Some aspects of non-medical use of narcotic substances

The article presents foreign data on the non-medical use of certain combinations of narcotic drugs, the range of their effects on the body of patients, as well as the development of state response measures and propaganda of the rejection of the use of narcotic drugs among populations at risk. It is noted that the use of narcotic drugs without medical indications is a global public health problem. In addition to the negative impact on health, the use of narcotic drugs aggravates existing mental illnesses, and on the other hand, the presence of mental pathology accelerates the formation of drug addiction.

Evidence of abnormal hot carrier thermalization at van Hove singularity of twisted bilayer graphene

Interlayer twist evokes revolutionary changes to the optical and electronic properties of twisted bilayer graphene (TBG) for electronics, photonics and optoelectronics. Although the ground state responses in TBG have been vastly and clearly studied, the dynamic process of its photoexcited carrier states mainly remains elusive. Here, we unveil the photoexcited hot carrier dynamics in TBG by time-resolved ultrafast photoluminescence (PL) autocorrelation spectroscopy. We demonstrate the unconventional ultrafast PL emission between the van Hove singularities (VHSs) with a ∼4 times prolonged relaxation lifetime. This intriguing photoexcited carrier behavior is ascribed to the abnormal hot carrier thermalization brought by bottleneck effects at VHSs and interlayer charge distribution process. Our study on hot carrier dynamics in TBG offers new insights into the excited states and correlated physics of graphene twistronics systems.

Clinical Value of Auditory Steady State Response Versus Tone Burst ABR for Evaluation of Severe to Profound Hearing Loss in Children

Clinical Value of Auditory Steady State Response Versus Tone Burst ABR for Evaluation of Severe to Profound Hearing Loss in Children

The eXact integral simplified time-dependent density functional theory (XsTD-DFT).

In the framework of simplified quantum chemistry methods, we introduce the eXact integral simplified time-dependent density functional theory (XsTD-DFT). This method is based on the simplified time-dependent density functional theory (sTD-DFT), where all semi-empirical two-electron integrals are replaced by exact one- and two-center two-electron integrals, while other approximations from sTD-DFT are kept. The performance of this new parameter-free XsTD-DFT method was benchmarked on excited state and (non)linear response properties, including ultra-violet/visible absorption, first hyperpolarizability, and two-photon absorption (2PA). For a set of 77 molecules, the results from the XsTDA approach were compared to the TDA data. XsTDA/B3LYP excitation energies only deviate on average by 0.14eV from TDA while drastically cutting computational costs by a factor of 20 or more depending on the energy threshold chosen. The absolute deviations of excitation energies with respect to the full scheme are decreasing with increasing system size, showing the suitability of XsTDA/XsTD-DFT to treat large systems. Comparing XsTDA and its predecessor sTDA, the new scheme generally improves excitation energies and oscillator strengths, in particular, for charge transfer states. TD-DFT first hyperpolarizability frequency dispersions for a set of push-pull π-conjugated molecules are faithfully reproduced by XsTD-DFT, while the previous sTD-DFT method provides redshifted resonance energy positions. Excellent performance with respect to the experiment is observed for the 2PA spectrum of the enhanced green fluorescent protein. The obtained robust accuracy similar to TD-DFT at a fraction of the computational cost opens the way for a plethora of applications for large systems and in high throughput screening studies.

Less-lethal weapons: ocular trauma in Chile as psychosocial trauma. Challenges from a human rights and comprehensive perspective.

In October 2019 in Chile, massive protests broke out in the so-called social uprising. The repressive response of the armed forces and Carabineros (Police) resulted in serious and mas-sive violations of human rights, with between 400 and 500 victims of ocular trauma caused mainly by shots from anti-riot shotguns, constituting the largest number of cases in the world linked to a single event. It is proposed to evaluate the different dimensions of the impact of ocular trauma due to state violence, using the concept of psychosocial trauma and a support model that integrates the medical-psychological and social dimensions. Human rights violations of the period are described, focusing on cases of ocular trauma, and state and civil society responses. The requests of a survivors' organisations regarding truth, justice and reparation is presented. A clinical case of ocular trauma treated in our centre is analyzed. Survivors of ocular trauma manifest post-traumatic reactions regardless of the severity of their ocular injuries. The impact on the mental health of survi-vors of ocular trauma due to state violence is a phenomenon where the psychic and psychosocial im-pact of trauma due to socio-political violence intersects with the short- and long-term mental health effects. The impact of sociopolitical trauma must be understood considering both the in-dividual and social subject, considering their cultural, socioeconomic and political reality. Recovery from traumatic psychological injury must be addressed in its medical, sensory rehabilitation, psycho-logical and psychosocial dimensions, including processes of social recognition, search for justice and comprehensive reparation of damage. In contexts of impunity, a model is proposed that integrates rehabilitation with psycho-legal support, promotion of agency and organisation, within the frame-work of commitment to the movement and principles of human rights.

Cascading risks in a social-ecological system: the South China Sea disputes

The situation in the South China Sea (SCS) is the epitome of a wicked problem where issues cross state boundaries and domains, and where stakeholders range from fishers to governments to shipping industries. This article frames the SCS as a social-ecological system that is composed of biological and social subsystems. It explains how, for over 70 years, global political and economic structures have conditioned state responses – territorialisation, militarisation, extraction, and exploitation – that, in turn, have led to cascading risks for further environmental degradation and conflict at different levels of community. This article uses the grammar of riskification, rather than securitisation, because the crisis in the SCS requires governance rather than military action. Any code of conduct needs to emphasise stewardship rather than ownership and to be climate-centred rather than threat-centred, in order to address the very real risk of the collapsing biological subsystem upon which the social subsystem ultimately depends.

Triad of violence: evolution and dynamics of conflict, terrorism, banditry and armed groups in northwest Nigeria

ABSTRACT This study is hinged on the theoretical framework of co-existence, convergence, cooperation and competition. It discusses the nature of interaction among armed groups, and their violent activities in northwest Nigeria. The determinants of the connections include geography, recruitment strategy, opportunities for mutual exchange of logistics and co-creation of violence. Bandits are outbidding ethno-religious militias, Ansaru, ISWAP, Boko Haram and herdsmen, and have committed 84% of recorded violence in the region from 2010 to 2022. This study highlights the implications of increasing footprints of armed groups and provides the imperatives for state response to protracted violence in northwest Nigeria. It concludes that the socio-economic problems that allow proliferation of armed groups and violent activities to fester must be addressed by the state. Even if ramped-up security responses turn northwest Nigeria into a police state, violence will continue until poverty, social inequality, injustice and gross failure of governance are tackled.

Systematic dissection of tumor-normal single-cell ecosystems across a thousand tumors of 30 cancer types

The complexity of the tumor microenvironment poses significant challenges in cancer therapy. Here, to comprehensively investigate the tumor-normal ecosystems, we perform an integrative analysis of 4.9 million single-cell transcriptomes from 1070 tumor and 493 normal samples in combination with pan-cancer 137 spatial transcriptomics, 8887 TCGA, and 1261 checkpoint inhibitor-treated bulk tumors. We define a myriad of cell states constituting the tumor-normal ecosystems and also identify hallmark gene signatures across different cell types and organs. Our atlas characterizes distinctions between inflammatory fibroblasts marked by AKR1C1 or WNT5A in terms of cellular interactions and spatial co-localization patterns. Co-occurrence analysis reveals interferon-enriched community states including tertiary lymphoid structure (TLS) components, which exhibit differential rewiring between tumor, adjacent normal, and healthy normal tissues. The favorable response of interferon-enriched community states to immunotherapy is validated using immunotherapy-treated cancers (n = 1261) including our lung cancer cohort (n = 497). Deconvolution of spatial transcriptomes discriminates TLS-enriched from non-enriched cell types among immunotherapy-favorable components. Our systematic dissection of tumor-normal ecosystems provides a deeper understanding of inter- and intra-tumoral heterogeneity.

Affective Responses to Acute Exercise: A Meta-Analysis of the Potential Beneficial Effects of a Single Bout of Exercise on General Mood, Anxiety, and Depressive Symptoms.

Acute exercise elicits various biobehavioral and psychological responses, but results are mixed with regard to the magnitude of exercise-induced affective reactions. This meta-analysis examines the magnitude of general mood state, anxiety, and depressive symptom responses to acute exercise while exploring exercise protocol characteristics and background health behaviors that may play a role in the affective response. A total of 2770 articles were identified from a MEDLINE/PubMed search and an additional 133 articles from reviews of reference sections. Studies had to have measured general mood before the acute exercise bout and within 30 minutes after exercise completion. Effect sizes were estimated using Hedges' g , with larger values indicating improvement in the outcome measure. A total of 103 studies were included presenting data from 4671 participants. General mood state improved from preexercise to postexercise ( g = 0.336, 95% confidence interval [CI] = 0.234-0.439). Anxiety ( g = 0.497, 95% CI = 0.263-0.730) and depressive symptoms ( g = 0.407, 95% CI = 0.249-0.564) also improved with exercise. There was substantial and statistically significant heterogeneity in each of these meta-analyses. This heterogeneity was not explained by differences in participants' health status. Meta-regression analyses with potential moderators (intensity of exercise, mode of exercise, usual physical activity level, or weight status of participants) also did not reduce the heterogeneity. This meta-analysis shows significantly improved general mood, decreased anxiety, and lower depressive symptoms in response to an acute bout of exercise. There was substantial heterogeneity in the magnitude of the effect sizes, indicating that additional research is needed to identify determinants of a positive affective response to acute exercise.