Screening Regime Research Articles

Antiscreening and Nonequilibrium Layer Electric Phases in Graphene Multilayers.

Screening is a ubiquitous phenomenon through which the polarization of bound or mobile charges tends to reduce the strengths of electric fields inside materials. Here, we show how photoexcitation can be used as a knob to transform conventional out-of-plane screening into antiscreening-the amplification of electric fields-in multilayer graphene. We find that, by varying the photoexcitation intensity, multiple nonequilibrium screening regimes can be accessed, including near-zero screening, antiscreening, and overscreening (reversing electric fields). Strikingly, at modest continuous wave photoexcitation intensities, the nonequilibrium polarization states become multistable, hosting light-induced ferroelectriclike steady states with nonvanishing out-of-plane polarization (and band gaps) even in the absence of an externally applied displacement field in nominally inversion symmetric stacks. This rich phenomenology reveals a novel paradigm of dynamical quantum matter that we expect will enable a variety of nonequilibrium broken symmetry phases.

Restrictions on Chinese SOE Investments for Data Security Reasons: The Case of Australia

In the digital age, the proliferation of investments made by Chinese state-owned enterprises (SOEs) has raised concerns among host countries about the risks that the investments could provide the Chinese government access to sensitive data involved in the target businesses, posing threats to their national security. Consequently, countries with sophisticated foreign investment screening (FIS) regimes, such as Australia, have imposed entry restrictions on Chinese SOE foreign direct investment (FDI) on the grounds of data security concerns. This article takes Australia as an example to investigate whether this concern has become a ‘panacea’ to justify any restrictions imposed by host states on Chinese SOE FDI in the digital age. Through in-depth examinations of Australia's reformed FIS regime and its application to Chinese SOE investments, this article demonstrates that data security has increasingly become a preferred justification for imposing restrictions on Chinese SOE investments. It argues that the data security justification is legitimate because of Chinese SOEs’ strong political ties, which have been significantly strengthened in China's ongoing SOE reforms, as well as China's prominent policy emphasis on data protection in recent years. However, measures should be taken to mitigate data security becoming a ‘minefield’ impeding the restoration of Australia–China investment relations.

Probing 2D Exciton Dynamics of Non-Hydrogenic Anisotropic Rydberg Spectra in Anomalous Screening Regime

Probing 2D Exciton Dynamics of Non-Hydrogenic Anisotropic Rydberg Spectra in Anomalous Screening Regime

Cross-sectional study examining factors impacting on uptake of postpartum type 2 diabetes screening among women diagnosed with hyperglycaemia in pregnancy

AimsEarly postpartum glucose screening of women with hyperglycaemia in pregnancy (HIP) can identify women who have the highest risk of developing impaired glucose tolerance and T2DM. This study examines the association between demographics, events during pregnancy, socioeconomic status and postpartum T2DM screening. MethodsUsing the French National Health Data System, this cross-sectional study included all deliveries where the mother had HIP in France in 2015, (n = 76,862). The odds ratio (OR) for attending postpartum screening was calculated via multi-level logistic regression. ResultsT2DM screening uptake at six months postpartum was 42·9% [95 % Confidence Interval: 42·6–43·3]. Several characteristics were associated with lower uptake: living in the most deprived area(OR = 0·78[0·74–0·83]); being < 25 years-old (reference age group 25–29;≤17: 0.53 [0·31–0·90];18–24: 0.73[0·69–0·78]); smoking (0·65[0·62–0·68]); obesity (0·93[0·89–0·97]); caesarean delivery (0·95[0·92–0·99]). Factors associated with higher uptake included primiparity (1·30[1·26–1·34]); having followed the French recommendations for HIP screening (1·24[1·20–1·28]); insulin prescription (1·75[1·69–1·81]) and pre-eclampsia (1·30[1·19–1·42]). p < 0.01 is justified due to sample size. ConclusionImproving identification of factors affecting postpartum T2DM screening uptake, such as demographics, socioeconomic context and events during pregnancy, may lead to development of target interventions to aide adherence to screening regime and thereby diagnosis of women with prediabetes or diabetes, for whom secondary and tertiary prevention is crucial.

Motion and teleportation of polar bubbles in low-dimensional ferroelectrics

Electric bubbles are sub-10nm spherical vortices of electric dipoles that can spontaneously form in ultra-thin ferroelectrics. While the static properties of electric bubbles are well established, little to nothing is known about the dynamics of these particle-like structures. Here, we reveal pathways to realizing both the spontaneous and controlled dynamics of electric bubbles in ultra-thin Pb(Zr0.4Ti0.6)O3 films. In low screening conditions, we find that electric bubbles exhibit thermally-driven chaotic motion giving rise to a liquid-like state. In the high screening regime, we show that bubbles remain static but can be continuously displaced by a local electric field. Additionally, we predict and experimentally demonstrate the possibility of bubble teleportation - a process wherein a bubble is transferred to a new location via a single electric field pulse of a PFM tip. Finally, we attribute the discovered phenomena to the hierarchical structure of the energy landscape.

Exploring Disparities in Breast Cancer Screening: An Ecological Analysis of Australian Data.

The objective of this study is to analyse the socio-spatial patterns of breast cancer screening across Australian regions. The research is an ecological study. Data for breast screening participation and associated social and demographic factors are obtained from the Australian Institute of Health and Welfare and the Australian Bureau of Statistics. The unit of measurement for the analysis is spatially aggregated regions (Statistical Area 3). Geographically weighted regression is used to analyse the relationship between a dependent variable and one or more independent variables while considering the spatial or geographic relationships among the data points. Globally, there was a significant (p<0.05) association between screening participation and income, English ability, education level, Indigenous background, and transport availability. The geographically weighted regression model represented an improved fit with a higher R2 (R2=0.89) and the Akaike information criterion (AIC) has improved, (AIC= 391.92). The Monte-Carlo tests for spatial variability were significant for all independent variables (p<0.05). Visually, there was marked spatial variation in the association between breast cancer screening rates and the significant independent variables from the global model. The identification of significant spatial variability in the association between breast cancer screening participation and important social and demographic factors provides important input into the design of programs aimed at increasing participation in screening regimes.

BIT·FTA상 외국인투자심사 실행에 관한 연구

Countries with foreign investment screening mechanism have developed practices to avoid international investment disputes. These practices include using security exceptions, exceptions to dispute settlement provisions, and schedules to Annex regarding non-conforming measures in investment agreements. These practices do not specify specific national security requirements and are subject to full self-judgment. Countries with a long history of foreign investment screening, such as the United States, Canada, and Australia, actively use these practices to exclude foreign investment screening from international agreement obligations. These countries interpret the national security exception jurisprudence as applying to foreign investment screening, meaning that foreign investment screening is entirely self-judged.&#x0D; However, South Korea does not have a consistent approach to foreign investment screening in its Bilateral Investment Treaties (BITs) and Free Trade Agreements (FTAs). The security exception clause in these agreements is different in each agreement, and the contents of the reservations are not uniform. However, it can be interpreted that Korea has decided to treat foreign investment screening as an exception to international law, since it joined the Regional Comprehensive Economic Partnership (RCEP), which stipulates that the screening regime shall not be subject to the dispute settlement provisions.&#x0D; Foreign investment screening is likely to become more important as a policy tool in the era of expanding national security. The concept of national security has evolved from being applied only in exceptional emergencies such as war to encompassing more permanent situations such as economic security, high-tech protection, supply chain crisis response, and climate change. State measures to protect national security have also become more permanent. Given these circumstances, it is important to reconsider whether it is appropriate to treat foreign investment screening as an exception to international law. Allowing foreign investment screening as an exception to international law could lead to a crisis in the international legal system due to potential abuse of this exception. However, from the government's perspective, securing policy space for foreign investment screening can be advantageous in effectively addressing the growing threat to national security. Therefore, it is crucial to contemplate the stance and standards that should be established for the foreign investment screening practice in Korea moving forward.

Molecular triaging options for women testing HPV positive with self-collected samples.

We review developments in molecular triaging options for women who test positive for high-risk human papillomavirus (hrHPV) on self-collected samples in the context of cervical cancer elimination. The World Health Organization (WHO) recommends hrHPV screening as the primary test for cervical screening due to its high sensitivity compared to other screening tests. However, when hrHPV testing is used alone for treatment decisions, a proportion of women of childbearing age receive unnecessary treatments. This provides the incentive to optimize screening regimes to minimize the risk of overtreatment in women of reproductive age. Molecular biomarkers can potentially enhance the accuracy and efficiency of screening and triage. HrHPV testing is currently the only screening test that allows triage with molecular methods using the same sample. Additionally, offering self-collected hrHPV tests to women has been reported to increase screening coverage. This creates an opportunity to focus health resources on linking screen-positive women to diagnosis and treatment. Adding an additional test to the screening algorithm (a triage test) may improve the test's positive predictive value (PPV) and offer a better balance of benefits and risks for women. Conventional triage methods like cytology and visual inspection with acetic acid (VIA) cannot be performed on self-collected samples and require additional clinic visits and subjective interpretations. Molecular triaging using methods like partial and extended genotyping, methylation tests, detection of E6/E7 proteins, and hrHPV viral load in the same sample as the hrHPV test may improve the prediction of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and invasive cancer, offering more precise, efficient, and cost-effective screening regimes. More research is needed to determine if self-collected samples are effective and cost-efficient for diverse populations and in comparison to other triage methods. The implementation of molecular triaging could improve screening accuracy and reduce the need for multiple clinical visits. These important factors play a crucial role in achieving the global goal of eliminating cervical cancer as a public health problem.

The rare circulating tumor microemboli as a biomarker contributes to predicting early colorectal cancer recurrences after medical treatment

Early prognosis of cancer recurrence remains difficult partially due to insufficient and ineffective screening biomarkers or regimes. This study evaluated the rare circulating tumor microemboli (CTM) from liquid biopsy individually and together with circulating tumor cells (CTCs) and serum CEA/CA19-9 in a panel, on early prediction of colorectal cancer (CRC) recurrence. Stained CTCs/CTM were detected by a microfluidic chip-based automatic rare-cell imaging platform. ROC, AUC, Kaplan-Meier survival, and Cox proportional hazard models regarding 4 selected biomarkers were analyzed. The relative risk, odds ratio, predictive accuracy, and positive/negative predictive value of biomarkers individually and in combination, to predict CRC recurrence were assessed and preliminarily validated. The EpCAM+Hochest+CD45− CTCs/CTM could be found in all cancer stages, where more recurrences were observed in late-stage cases. Significant correlations between CTCs/CTM with metastatic stages and clinical treatment were illustrated. CA19-9 and CTM could be seen as independent risk factors in patient survivals, while stratified patients by grouped biomarkers on the Kaplan-Meier analyses presented more significant differences in predicting CRC recurrences. By monitoring the panel of selected biomarkers, disease progressions of 4 CRC patients during follow-up visits after first treatments within 3 years were predicted successfully. This study unveiled the value of rare CTM on clinical studies and a panel of selected biomarkers on predicting CRC recurrences in patients at the early time after medical treatment, in which the CTM and serum CA19-9 could be applied in clinical surveillance and CRC management to improve the accuracy.

Drag Resistivity of Hole-Hole Static Interactions with the Effect of Non- Homogeneous Dielectric Medium

BACKGROUND: We have study the Coulomb drag phenomena for hole-hole static potentials theoretically and measured numerically using the random phase approximation (RPA) method OBJECTIVE: The drag resistivity is evaluated at low temperature, large interlayer separation limit and weakly screening regime, with the geometry of two atomically thin materials, such as, BLG/GaAs based multilayer system, is a promising systems in nanomaterials and technology METHOD: Static local field corrections (LFC) are considered to take into account the Exchange-correlations (XC) and mutual interaction effects with varying concentrations of active and passive layer RESULT: It is found that the drag resistivity is found enhanced on using the LFC effects and increases on increasing the effective mass. In Fermi-Liquid regime, drag resistivity is directly proportional to T^2, n^(-3), d^(-4) and ϵ^2 with respect to temperature (T), density (n), interlayer separation (d~nm) and dielectric constant (ϵ_2), respectively. CONCLUSION: Dependency of drag resistivity is measured and compared to 2D e-e and e-h coupled-layer systems with and without the effect of non-homogeneous dielectric medium.

Inward foreign investment screening targets China: interdisciplinary perspectives*

Screening of inward foreign investment in numerous countries worldwide has heightened in recent years for a range of reasons, one of which is the volume of Chinese outward investment. Moulding screening policies around concerns about Chinese investment has been a common pattern, particularly among developed countries and allies of the United States. The application of screening measures to Chinese investments in particular is also seen in recent practice in numerous countries. These developments create potential inconsistencies with international investment law, at least for those countries with an international investment agreement with China. The 2020 arbitral award in Global Telecom v Canada shows that even a provision that explicitly excludes investment screening decisions from a bilateral investment treaty may not apply to prevent all related investment treaty claims. The increased use of screening as a policy tool, with respect to China and otherwise, also raises questions about economic rationale and impact. Put simply, blocking a foreign investment proposal may have negative effects on shareholders, jobs and the economy itself, while even the existence of a restrictive screening regime and the threat of the imposition of conditions on a deal may dampen the appeal for foreign investors.

Efficiency analysis of rapid antigen test based SARS-CoV-2 in hospital contact tracing and screening regime: test characteristics and cost effectiveness

In the context of the current SARS-CoV-2 pandemic, reliable and cost-efficient screening and testing strategies are crucial to prevent disease transmission and reduce socioeconomic losses. To assess the efficiency of a rapid antigen test (RAT)-based SARS-CoV-2 contact-tracing and screening regime, we conducted a retrospective analysis of RAT and polymerase chain reaction (PCR) test data over a 1-year period, assessed test characteristics and estimated cost-effectiveness. The RAT had a sensitivity of 70.2% overall and 89.3% for people with a high risk of infectivity. We estimated inpatient treatment and quarantined healthcare worker costs of over € 5860.83, whereas the cost of identifying one SARS-CoV-2 positive person by RAT for our patient cohort was € 1210.75. In contrast, the estimated respective PCR cost was € 5043.32. Therefore, a RAT-based contract tracing and screening regime may be an efficient and cost-effective way to contribute to the early identification and prevention of SARS-CoV-2 transmission.

Effect of a temperature gradient on the screening properties of ionic fluids

The electrostatic screening properties of ionic fluids are of paramount importance in countless physical processes. Yet the screening behavior of ionic conductors out of thermal equilibrium has to date mainly been studied in the context of thermoelectric phenomena by virtue of direct extensions of Debye-H\"uckel theories. We investigate how the static response of a symmetric ionic fluid is influenced by the presence of a thermal gradient by introducing a theory of electrostatic screening under a stationary temperature profile. By borrowing mathematical methods commonly used in the semiclassical approximation of quantum particles, we find analytical solutions to the asymptotic decay of the charge density which can be used to describe the nonequilibrium response of the system to external charge perturbations and for arbitrary ionic concentrations. Notably, a transition between monotonic and oscillatory screening regimes is observed as an effect of the temperature variation which generalizes known results of thermal equilibrium to out of equilibrium conditions. A final quantitative example on the screening of charged surfaces in aqueous electrolytes shows that the deviation from thermal equilibrium predicted by our solutions is generally larger than thermoelectric effects and should therefore be taken into account for a comprehensive description of the electrical double layer. Our findings pave the way to the rigorous treatment of nonequilibrium steady states in ionic systems with potential applications to the study of energy materials, nanostructured systems, and waste-heat-recovery technologies.

Second harmonic generation at the edge of a two-dimensional electron gas

We show that driving a two-dimensional electron gas by an in-plane electric field oscillating at the frequency $\omega$ gives rise to an electric current at $2\omega$ flowing near the edge of the system. This current has both parallel and perpendicular to the edge components, which emit electromagnetic waves at $2\omega$ with different polarizations. We develop a microscopic theory of such an edge second harmonic generation and calculate the edge current at $2\omega$ in different regimes of electron transport and electric field screening. We also show that at high frequencies the spatial profile of the edge current contains oscillations caused by excitation of plasma waves.

Follow-Up of Plasma Donors after Quarantine Storage: Results of a 5-Year Survey in Germany

Background and Objectives: In 1993, a quarantine storage of 6 months was introduced for plasma for transfusion and was reduced to 4 months in 2003, owing to the improvements of screening assays used in German blood establishments. The presented survey analyses the value of quarantine storage under the current screening conditions. Materials and Methods: From 2015 to 2019, we collected data on the total amount of released quarantine plasma as well as on the number of quarantine plasma not released due to a reactive screening test of a follow-up donation. Results: Responding establishments covered 84% of plasma units released within the sampled period. In 3,583,913 (99.98%) of the total 3,584,664 test pairs, all screening assays revealed a negative result, leading to plasma release from quarantine storage. In 442 out of the residual 751 cases, confirmed positive results for human immunodeficiency virus (24), hepatitis C virus (22), or hepatitis B virus (396) were obtained in the follow-up donations. Of them, 372 revealed negative ID-NAT results in their retain samples confirmed by using highly sensitive individual donor nucleic acid amplification technology. In 70 cases, no testing of retain samples was performed as plasma was released for fractionation. The maximum theoretical risk for an undetected human immunodeficiency virus, hepatitis C or B virus infection was less than 0.0001%. Conclusion: No positive donation were found under the current screening regime and the quarantine storage during the 5-year survey period. In view of the current type and sensitivity of screening tests in German blood establishments, the results allow a reassessment of the value of quarantine storage of plasma regarding duration and release modalities. Due to the more sensitive donor screening, shorter quarantine periods as well as dispensing quarantine storage can be discussed. A reduction in the safety standard of plasma transfusions need not be feared, and the availability of plasma for transfusions could be facilitated.

Multiplet effects in the electronic correlation of one-dimensional magnetic transition metal oxides on metals

We use the constrained random phase approximation (cRPA) method to calculate the Hubbard $U$ parameter in four one-dimensional magnetic transition metal atom oxides of composition XO$_2$ (X = Mn, Fe, Co, Ni) on Ir(100). In addition to the expected screening of the oxide, i.e., a significant reduction of the $U$ value by the presence of the metal substrate, we find a strong dependence on the electronic configuration (multiplet) of the X($d$) orbital. Each particular electronic configuration attained by atom X is dictated by the O ligands, as well as by the charge transfer and hybridization with the Ir(100) substrate. We find that MnO$_2$ and NiO$_2$ chains exhibit two different screening regimes, while the case of CoO$_2$ is somewhere in between. The electronic structure of the MnO$_2$ chain remains almost unchanged upon adsorption. Therefore, in this regime, the additional screening is predominantly generated by the electrons of the neighboring metal surface atoms. The screening strength for NiO$_2$/Ir(100) is found to depend on the Ni($d$) configuration in the adsorbed state. The case of FeO$_2$ shows an exceptional behavior, as it is the only insulating system in the absence of metallic substrate and, thus, it has the largest $U$ value. However, this value is significantly reduced by the two mentioned screening effects after adsorption.

Incoming: How International Investment Law Constrains Foreign Investment Screening

Abstract Domestic screening of foreign investment, often on national security grounds, has intensified in recent years. More countries are introducing such regimes, while others expand their scope or allow retrospective screening. These developments increase the potential for investor–State claims under international investment agreements, even sometimes regarding investments that are not yet established. Host States need to be aware of the potential for adverse screening decisions, the imposition of conditions, or due process shortcomings to conflict with investment obligations, such as fair and equitable treatment or most-favoured nation treatment. Although tools exist in some treaties to exclude or exempt investment screening, these may not prevent a successful investment claim. For example, listing a screening regime as a non-conforming measure may not cover all future amendments, and general and security exceptions are subject to considerable uncertainty. Host States need to ensure compliance with international investment law in creating and developing screening regimes.

Multi-Steps Magnetic Flux Entrance/Exit at Thermomagnetic Avalanches in the Plates of Hard Superconductors.

Avalanche cascades of magnetic flux have been detected at thermomagnetic instability of the critical state in the plates of Nb-Ti alloy. It was found that, the magnetic flux Φ enters conventional superconductor in screening regime and leaves in trapping regime in the form of a multistage “stairways”, with the structure dependent on the magnetic field strength and magnetic history, with approximately equal successive portions ΔΦ in temporal Φ(t) dependence, and with the width depending almost linearly on the plate thickness. The steady generation of cascades was observed for the full remagnetization cycle in the field of 2–4 T. The structure of inductive signal becomes complex already in the field of 0–2 T and it was shown, on the base of Fourier analysis, that, the avalanche flux dynamic produces, in this field range, multiple harmonics of the electric field. The physical reason of complex spectrum of the low-field avalanche dynamics can be associated with rough structure of moving flux front and with inhomogeneous relief of induction. It was established that the initiation of cascades occurs mainly in the central part of the lateral surface. The mechanism of cascades generation seems to be connected to the “resonator’s properties” of the plates.

Regulation (EU) 2019/452 and the Foreign Direct Investment Screening Regime in Romania

Since 11 October 2020, Regulation (EU) 2019/452 of the European Parliament and of the Council establishing a framework for the screening of foreign direct investment into the EU has been applied in the Member States of the European Union. Although the Regulation is automatically and uniformly applicable in all EU countries upon its entry into force – thus, no transposition into national law is required –, Romania is preparing to adopt legislation to regulate FDI due diligence at national level in line with Regulation (EU) 2019/452, in the absence of an adequate legal framework and for the purpose of implementing the Regulation. In this study, we intend to examine the current legal framework in Romania on FDI and the draft legislation mentioned above, which aims to establish a workable screening mechanism for FDI into Romania.

Self-consistent relaxation theory of collective ion dynamics in Yukawa one-component plasmas under intermediate screening regimes.

The self-consistent relaxation theory is employed to describe the collective ion dynamics in strongly coupled Yukawa classical one-component plasmas. The theory is applied to equilibrium states corresponding to intermediate screening regimes with appropriate values of the structure and coupling parameters. The information about the structure (the radial distribution function and the static structure factor) and the thermodynamics of the system are sufficient to describe collective dynamics over a wide range of spatial scales, namely, from the extended hydrodynamic to the microscopic dynamics scale. The main experimentally measurable characteristics of the equilibrium collective dynamics of ions-the spectrum of the dynamic structure factor, the dispersion parameters, the speed of sound, and the sound attenuation-are determined within the framework of the theory without using any adjustable parameters. The results demonstrate agreement with molecular dynamics simulations. Thus a direct realization is presented of the key idea of statistical mechanics: for the theoretical description of the collective particle dynamics in equilibrium fluids it is sufficient to know the interparticle interaction potential and the structural characteristics. Comparison with alternative or complementary theoretical approaches is provided.