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A photonic crystal microcavity with the tunable Q factor has been implemented on the basis of a bound state in the continuum using the advanced liquid crystal cell technology platform. It has been shown that the Q factor of the microcavity changes from 100 to 360 in the voltage range of 0.6 V.

The article deals with the institutional performance of the U.S. executive power on the policy of sanctions. The topic is much less reflected in the literature in comparison with “canonical” issues like sanctions efficiency or particular case-studies of sanctions implementation. The goal is to fill in the gap in the literature on the following research questions. How do the U.S. sanctions policy executive institutions work? What is an extant of their involvement into the policy of sanctions? What is the balance of power between them? Why are particular institutes more active in comparison with others, and does it mean greater influence in terms of decision-making and implementation? The hypothesis implies that the U.S. executive institutions compose an imbalanced system with a skew in favor of the Department of the Treasury. However, this skew is smoothed by functional exclusiveness of other institutions and the impact of their decisions on sanctioned persons and states. “Sanctions Events Database” is used to test this assumption. Events are classified in terms of their institutional initiator (Department of the Treasury, Department of State, etc.), target states or problems, types of action, etc. The data is taken from open sources. It reflects a “micro-level” of institutional performance, depicting its everyday practice. The analysis demonstrates that a majority of events are connected to the Department of the Treasury, which is most active in comparison with other institutions. The Department of Commerce initiates much less events, however, the coverage of affected persons under its restrictions may be comparable to the one of the Treasury. The Department of Justice also initiates much less events, but the consequences for targets are harder due to criminal enforcement functions of the Department. The article relies on the 2020 data-set. This data is enough to understand basic trends of the U.S. executive institutions performance related to the policy of sanctions. Still, more data is needed to avoid possible fluctuations related to particular years.

The degree of disability that is acceptable to patients following traumatic brain injury (TBI) continues to be debated. While the dichotomization of outcome on the Glasgow Outcome Score (GOSE) into 'favourable' and 'unfavourable' continues to guide clinical decisions, this may not reflect an individual's subjective experience. The aim of this study is to assess how patients' self-reported quality of life (QoL) relates to objective outcome assessments and how it compares to other debilitating neurosurgical pathologies, including subarachnoid haemorrhage (SAH) and cervical myelopathy.A retrospective analysis of over 1300 patients seen in Addenbrooke's Hospital, Cambridge, UK with TBI, SAH and patients pre- and post- cervical surgery was performed. QoL was assessed using the SF-36 questionnaire. Kruskal-Wallis test was used to analyse the difference in SF-36 domain scores between the four unpaired patient groups. To determine how the point of dichotomization of GOSE into 'favourable' and 'unfavourable' outcome affected QOL, SF-36 scores were compared between GOSE and mRS.There was a statistically significant difference in the median Physical Component Score (PCS) and Mental Component Score (MCS) of SF-36 between the three neurosurgical pathologies. Patients with TBI and SAH scored higher on most SF-36 domains when compared with cervical myelopathy patients in the severe category. While patients with Upper Severe Disability on GOSE showed significantly higher PC and MC scores compared to GOSE 3, there was a significant degree of variability in individual responses across the groups.A significant number of patients following TBI and SAH have better self-reported QOL than cervical spine patients and patients' subjective perception and expectations following injury do not always correspond to objective disability. These results can guide discussion of treatment and outcomes with patients and families.

After traumatic brain injury (TBI), cerebral metabolism can become deranged, contributing to secondary injury. Cerebral microdialysis (CMD) allows cerebral metabolism assessment and is often used with other neuro-monitoring modalities. CMD-derived parameters such as the lactate/pyruvate ratio (LPR) show a failure of oxidative energy generation. CMD-based abnormal metabolic states can be described following TBI, informing the etiology of physiological derangements. This systematic review summarizes the published literature on microdialysis-based abnormal metabolic classifications following TBI. Original research studies in which the populations were patients with TBI were included. Studies that described CMD-based classifications of metabolic abnormalities were included in the synthesis of the narrative results. A total of 825 studies underwent two-step screening after duplicates were removed. Fifty-three articles that used CMD in TBI patients were included. Of these, 14 described abnormal metabolic states based on CMD parameters. Classifications were heterogeneous between studies. LPR was the most frequently used parameter in the classifications; high LPR values were described as metabolic crisis. Ischemia was consistently defined as high LPR with low CMD substrate levels (glucose or pyruvate). Mitochondrial dysfunction, describing inability to use energy substrate despite availability, was identified based on raised LPR with near-normal levels of pyruvate. This is the first systematic review summarizing the published literature on microdialysis-based abnormal metabolic states following TBI. Although variability exists among individual classifications, there is broad agreement about broad definitions of metabolic crisis, ischemia, and mitochondrial dysfunction. Identifying the etiology of deranged cerebral metabolism after TBI is important for targeting therapeutic interventions.

For a long time, the US has been a global leader in terms of use of unilateral sanctions. However, the EU is getting increasingly active as sanctions’ initiator. Currently, the EU runs at least 26 regimes of sanctions to address relations with foreign states or tackle functional problems like human rights, nonproliferation, cyber security or counterterrorism. Russia is one of the targets. The EU sanctions policy raises a number of research questions. How active is the EU policy in comparison with other initiators? What are the peculiarities of the EU institutional process of sanctions implementation? What are the key targets and what is the distribution of EU decisions and actions among those targets? To address these questions the article provides analysis of Sanctions Events Database (SED), designed by Russian International Affairs Council. The research implies empirical analysis of EU sanctions policy everyday events in 2020. It also covers sanctions and enforcement actions of separate EU members as well as alignment with the EU sanctions of the third countries. The article attempts to fill in the gap in the literature between quantitative analysis of multiple sanctions cases on the one hand and in-depth analysis of particular cases on the other. It makes a special focus on EU sanctions related to Russia.

IntroductionCranioplasty is a widely practised neurosurgical procedure aimed at reconstructing a skull defect, but its impact on a patient’s rehabilitation following a traumatic brain injury (TBI) or stroke could be better understood. In addition, there are many issues that a TBI patient or the patient who had a stroke and their families may have to adapt to. Insight into some of the potential social barriers, including issues related to social engagement and cosmetic considerations, would be beneficial. Currently, little is known about how this procedure impacts a patient’s recovery, the patient’s perceptions of rehabilitation precranioplasty and postcranioplasty and the broader issues of cosmesis and social reintegration. This study hopes to understand some of these issues and therefore help inform clinicians of some of the difficulties and perceptions that patients and their relatives may have.Methods and analysisA mixed-methods study. Data will be collected through focus groups with healthcare professionals (HCPs) and semi-structured interviews with patients and their relatives, field notes, a researcher diary and a patient questionnaire. Different perspectives will be brought together through method triangulation. Patient and relative data will be analysed using interpretive phenomenological analysis, and HCPs data will be analysed thematically using deductive and inductive coding.Ethics and disseminationEthical approval has been obtained from the Wales REC 7 ethics committee (Rec ref: 19/WA/0315). There is limited literature regarding a patient’s perception of the cranioplasty process, the potential impact on rehabilitation and how this may impact their reintegration into the community. The results of this study will be presented at national brain injury conferences and published in peer-reviewed, national and international journals.

Background The Ottawa subarachnoid haemorrhage (SAH) rule and the Emerald SAH rule are clinical decision tools to aid in the decision for computed tomography (CT) of the head in patients attending an emergency department (ED) with acute non-traumatic headache. The objective of this study was to analyse the performance of these rules in a contemporary UK cohort. Methods We performed a retrospective external validation study. Patients undergoing CT of the head for the evaluation and treatment of non-traumatic headaches over a 6-month period in the ED at two tertiary centres were assessed. Each patient’s Ottawa rule and Emerald rule were calculated and compared with their final diagnosis. Results The cohort consisted of 366 patients and there were 16 cases of SAH (based on CT findings or the presence of xanthochromia in cerebrospinal fluid). The Ottawa rule identified 288 patients requiring CT of the head. The sensitivity of the Ottawa rule was 100% (95% confidence interval (CI) 71–100%) and the specificity was 22% (95% CI 18–27%). The Emerald rule identified 267 patients who required CT, and achieved a sensitivity of 81% (95% CI 54–96%) and a specificity of 27% (95% CI 23–32%). Conclusions The Ottawa SAH rule correctly identified all patients with SAH in this contemporary cohort. The Emerald rule did not perform as well in this cohort and is unsuitable for clinical use. The Ottawa rule is a useful tool to aid in the decision for CT of the head in patients presenting with acute non-traumatic headache to the ED.

BACKGROUND Core outcome sets (COSs) are important and necessary as they help standardize reporting in research studies. Cranioplasty following traumatic brain injury (TBI) or stroke is becoming increasingly common, leading to an ever-growing clinical and research interest, especially regarding the optimal material, cost-effectiveness, and timing of cranioplasty concerning neurological recovery and complications. Consequently, heterogeneous reporting of outcomes from such diverse studies has led to limited meta-analysis ability and an ongoing risk of outcome reporting bias. This study aims to define a standardized COS for reporting in all future TBI and stroke cranioplasty studies. OBJECTIVE This study has four aims: (1) undertake a systematic review to collate the most current outcome measures used within the cranioplasty literature; (2) undertake a qualitative study to understand better the views of clinicians, patients' relatives, and allied health professionals regarding clinical outcomes following cranioplasty; (3) undertake a Delphi survey as part of the process of gaining consensus for the COS; and (4) finalize consensus through a consensus meeting resulting in the COS. METHODS An international steering committee has been formed to guide the development of the COS. In addition, recommendations from other clinical initiatives such as COMET (Core Outcomes and Effectiveness Trials) and OMERACT (Outcome Measures in Rheumatology) have been adhered to. Phase 1 is data collection through a systematic review and qualitative study. Phase 2 is the COS development through a Delphi survey and consensus meetings with consensus definitions decided and agreed upon before the Delphi survey begins to avoid bias. RESULTS Phase 1 started at the end of 2019, following ethical approval in December 2019, and the project completion date is planned for the end of 2022 or beginning of 2023. CONCLUSIONS This study should result in a consensus on a COS for cranioplasty, following TBI or stroke, to help standardize outcome reporting for future studies, which can be applied to future research and clinical services, help align future studies, build an increased understanding of cranioplasty and its impact on a patient’s function and recovery, and help standardize the evidence base. INTERNATIONAL REGISTERED REPORT DERR1-10.2196/37442

The article aims to explore the impact of the COVID-19 pandemic on the use of sanctions as a foreign policy tool. The following research questions are posed: in what way did COVID-19 affect the policy of sanctions around the world? To what extant did the initiators of sanctions change their restrictions? Where did COVID-19 rank on the global sanctions agenda? What was the position of the UN as a key institution of global governance and what was the reaction of the key countries that initiated the sanctions? The main hypothesis is that COVID-19 has not significantly altered the existing sanctions regime. No single initiator-state has changed its sanctions regime in principle, but states have made a number of humanitarian exemptions. However, these exemptions are limited and sanctions have continued to be imposed as usual. In some areas, COVID-19 has even exacerbated international tensions and raised the risks of sanctions, especially in U. S.—China relations. The hypothesis was tested using the event analysis method of sanctions episodes during the pandemic (March-June 2020). The research provides an analysis of quantity and quality of events and their distribution among initiators. Emphasis is placed on the study of events connected to COVID-19. The results reveal a limited impact of COVID-19 on sanctions policy and highlight the weakness of the UN to affect the behavior of key sanctions initiators even in conditions of a global threat such as COVID-19.

The effect of the shape of the nanoparticles and the polarization of incident light on the surface current density and the efficiency of an organic solar cell based on the Tamm plasmon polariton is investigated. In the cases of both elongated and flattened nanoparticles, it is shown that the efficiency of such a solar cell is increased when the electric field vector is parallel to the largest axis of the spheroid.

Following traumatic brain injury (TBI), raised cerebral lactate/pyruvate ratio (LPR) reflects impaired energy metabolism. Raised LPR correlates with poor outcome and mortality following TBI. We prospectively recruited patients with TBI requiring neurocritical care and multimodal monitoring, and utilised a tiered management protocol targeting LPR. We identified patients with persistent raised LPR despite adequate cerebral glucose and oxygen provision, which we clinically classified as cerebral ‘mitochondrial dysfunction’ (MD). In patients with TBI and MD, we administered disodium 2,3-13C2 succinate (12 mmol/L) by retrodialysis into the monitored region of the brain. We recovered 13C-labelled metabolites by microdialysis and utilised nuclear magnetic resonance spectroscopy (NMR) for identification and quantification. Of 33 patients with complete monitoring, 73% had MD at some point during monitoring. In 5 patients with multimodality-defined MD, succinate administration resulted in reduced LPR(−12%) and raised brain glucose(+17%). NMR of microdialysates demonstrated that the exogenous 13C-labelled succinate was metabolised intracellularly via the tricarboxylic acid cycle. By targeting LPR using a tiered clinical algorithm incorporating intracranial pressure, brain tissue oxygenation and microdialysis parameters, we identified MD in TBI patients requiring neurointensive care. In these, focal succinate administration improved energy metabolism, evidenced by reduction in LPR. Succinate merits further investigation for TBI therapy.

Microglia, the tissue-resident macrophages of the central nervous system (CNS), play critical roles in immune defense, development and homeostasis. However, isolating microglia from humans in large numbers is challenging. Here, we profiled gene expression variation in primary human microglia isolated from 141 patients undergoing neurosurgery. Using single-cell and bulk RNA sequencing, we identify how age, sex and clinical pathology influence microglia gene expression and which genetic variants have microglia-specific functions using expression quantitative trait loci (eQTL) mapping. We follow up one of our findings using a human induced pluripotent stem cell-based macrophage model to fine-map a candidate causal variant for Alzheimer's disease at the BIN1 locus. Our study provides a population-scale transcriptional map of a critically important cell for human CNS development and disease.

This article examines the origins of the United States’ supremacy in the use of economic sanctions in the context of a wider discussion about the structure of the contemporary world order following the Cold War. Sanctions are understood as an instrument of power relations and a means of forcing “target” countries to fulfil the requirements of “sender” countries. The experience of deploying sanctions suggests that, from the point of view of economic power, the world today retains signs of unipolarity, while a polycentric world order is just one of the possible options for the future. The key research question is: why does the United States continue to have significant leverage in terms of implementing sanctions, despite the growing capabilities of other actors? In addition to U.S. dominance in the global financial system, two other factors are highlighted. The first is the relative weakness of the United Nations (UN) as a key global governance institution. While the United Nations is the only legitimate source of sanctions, it has far fewer institutional capabilities to run a sanctions policy compared to the United States. At the same time, the United States and other western powers successfully use the United Nations to increase the legitimacy of the unilateral measures, or play an active role in the UN Security Council, striving to legitimize their programmes and then supplementingthem with their own unilateral measures. The second factor is the difference in the perception of sanctions by national governments and private companies. While national governments often criticize unilateral sanctions, private business tends to comply or over-comply with U.S. measures, even when the national government tries to protect it. As a result, even the most powerful economic actors cannot convert their economic power into political power to counterbalance the United States. The question of how long the United States will be able to maintain its supremacy, and how effective the sanctions will be, is a focus of future research.

Background Cranioplasty is an increasingly common procedure performed in neurosurgical centres following a decompressive craniectomy (DC), however, timing of the procedure varies greatly. Objectives The aim of this study is to compare the surgical outcomes of an early compared to a late cranioplasty procedure. Methods Ninety adult patients who underwent a prosthetic cranioplasty between 2014 and 2017 were studied retrospectively. Timing of operation, perioperative complications and length of stay were assessed. Early and late cranioplasties were defined as less or more than 3 months since craniectomy respectively. Results Of the 90 patients, 73% received a late cranioplasty and 27% received an early cranioplasty. The median interval between craniectomy and cranioplasty was 13 months [range 3–84] in late group versus 54 days [range 33–90] in early group. Twenty-two patients in the early group (91%) received a cranioplasty during the original admission while undergoing rehabilitation. Complications were seen in 25 patients (28%). These included wound or cranioplasty infection, hydrocephalus, symptomatic pneumocephalus, post-operative haematoma and cosmetic issues. The complication rate was 21% in the early group and 30% in the late group (P value 0.46). There was no significant difference in the rate of infection or hydrocephalus between the two groups. Length of stay was not significantly increased in patients who received an early cranioplasty during their initial admission (median length of stay 77 days versus 63 days, P value 0.28). Conclusion We have demonstrated the potential for early cranioplasty to be a safe and viable option, when compared to delayed cranioplasty.

Objective Surgical treatment of ventrally located intradural cysts is difficult and controversial. Laminectomy with division of the denticulate ligaments and gentle cord mobilization remains the standard approach but risks further neurologic deterioration secondary to cord manipulation. Our purpose is to evaluate the safety and effectiveness of a midline cord-splitting approach as an alternative for treating ventral thoracic intradural cysts. Methods We describe 2 patients who were treated for ventral intradural cysts causing progressive and severe myelopathy. Under general anesthesia and continuous neurophysiologic monitoring, laminectomy, durotomy, and cord splitting through a midline approach gave direct access to both lesions. Cyst drainage was supplemented by a cystopleural shunt in 1 case. Results Cyst collapse and cord reexpansion were documented in both patients with a magnetic resonance imaging scan 1 week after surgery. In both cases there was a significant neurologic improvement, which was maintained 2 years postoperatively. Intraoperative monitoring recorded no loss of somatosensory or motor potentials during surgery. Follow-up magnetic resonance imaging scans 2 years postoperatively showed no evidence of cyst recurrence, and both patients remained neurologically improved and stable. Conclusions We have been able to drain 2 ventral intradural cysts using a cord-splitting technique. This has allowed safe access to purely ventrally located lesions, which were inaccessible dorsally or dorsolaterally. By using this method we have been able to avoid a more invasive ventral transthoracic approach necessitating vertebrectomy and reconstruction and risking serious complications.

Anterior cervical discectomy and fusion (ACDF) is a well-standardized treatment for cervical myelopathy/radiculopathy. The aim of this study is to assess the feasibility of minimally invasive ACDF. Retrospective review of six patients who underwent minimally invasive ACDF using microscope and tubular retractors. Clinical and radiological outcomes and surgical complications were reviewed. Minimally invasive microscopic ACDF through tubular retractors is a feasible option and therefore an alternative to conventional open procedures. However, it does require advanced technical skills and good understanding of the MIS principles and limitations of the technique.

Despite Biden’s victory in the 2020 U.S. election and his initial strive to see the JCPOA salvaged, the maximum pressure campaign against the Islamic Republic still de facto and de jure remains in place. With both Iran and the U.S. asserting intransigent positions towards each other and refusing to make the first step, the future of the JCPOA and the economic sanctions associated with the deal looks vague to say the least. For the time being, it is hard to expect that the “maximum pressure” campaign designed by Trump’s administration will experience any significant change in the near future even with Biden willing to reconcile with Tehran. In this context it is important to assess just how efficient this sanction policy towards Iran is and whether it is likely to bear any fruit in the near future. This chapter attempts to analyze the prospects of current pressure campaign employed by the U.S. against Iran, arguing that the maintained sanction policies are not very likely to win any significant concessions from Tehran.

An electrode of a light-induced cell for water splitting based on a broadband Tamm plasmon polariton localized at the interface between a thin TiN layer and a chirped photonic crystal has been developed. To facilitate the injection of hot electrons from the metal layer by decreasing the Schottky barrier, a thin n-Si film is embedded between the metal layer and multilayer mirror. The chipping of a multilayer mirror provides a large band gap and, as a result, leads to an increase in the integral absorption from 52 to 60 percent in the wavelength range from 700 to 1400 nm. It was shown that the photoresponsivity of the device is 32.1 mA/W, and solar to hydrogen efficiency is 3.95%.

Decompressive craniectomy (DC) in traumatic brain injury (TBI) has been suggested to influence cerebrovascular reactivity. We aimed to determine if the statistical properties of vascular reactivity metrics and slow-wave relationships were impacted after DC, as such information would allow us to comment on whether vascular reactivity monitoring remains reliable after craniectomy. Using the CENTER-TBI High Resolution Intensive Care Unit (ICU) Sub-Study cohort, we selected those secondary DC patients with high-frequency physiological data for both at least 24 h pre-DC, and more than 48 h post-DC. Data for all physiology measures were separated into the 24 h pre-DC, the first 48 h post-DC, and beyond 48 h post-DC. We produced slow-wave data sheets for intracranial pressure (ICP) and mean arterial pressure (MAP) per patient. We also derived a Pressure Reactivity Index (PRx) as a continuous cerebrovascular reactivity metric updated every minute. The time-series behavior of the PRx was modeled for each time period per patient. Finally, the relationship between ICP and MAP during these three time periods was assessed using time-series vector autoregressive integrative moving average (VARIMA) models, impulse response function (IRF) plots, and Granger causality testing. Ten patients were included in this study. Mean PRx and proportion of time above PRx thresholds were not affected by craniectomy. Similarly, PRx time-series structure was not affected by DC, when assessed in each individual patient. This was confirmed with Granger causality testing, and VARIMA IRF plotting for the MAP/ICP slow-wave relationship. PRx metrics and statistical time-series behavior appear not to be substantially influenced by DC. Similarly, there is little change in the relationship between slow waves of ICP and MAP before and after DC. This may suggest that cerebrovascular reactivity monitoring in the setting of DC may still provide valuable information regarding autoregulation.

Microglia, the tissue resident macrophages of the CNS, are implicated in a broad range of neurological pathologies, from acute brain injury to dementia. Here, we profiled gene expression variation in primary human microglia isolated from 141 patients undergoing neurosurgery. Using single cell and bulk RNA sequencing, we defined distinct cellular populations of acutelyin vivo-activated microglia, and characterised a dramatic switch in microglial population composition in patients suffering from acute brain injury. We mapped expression quantitative trait loci (eQTLs) in human microglia and show that many disease-associated eQTLs in microglia replicate well in a human induced pluripotent stem cell (hIPSC) derived macrophage model system. Using ATAC-seq from 95 individuals in this hIPSC model we fine-map candidate causal variants at risk loci for Alzheimer’s disease, the most prevalent neurodegenerative condition in acute brain injury patients. Our study provides the first population-scale transcriptional map of a critically important cell for neurodegenerative disorders.

Background: Patients with titanium cranioplasties can develop skin defects and plate exposure requiring revision surgery to prevent infection. The management of these patients has historically been...

Background The outcome following traumatic brain injury (TBI) is heterogeneous and poorly defined and physical disability scales like the extended Glasgow Outcome Score (GOSE) while providing valuation information in terms of broad categorisation of outcome are unlikely to capture the full spectrum of deficits. Quality of life questionnaires such as SF-36 are emerging as potential tools to help characterise factors important to patients’ recovery. This study assessed the association between physical disability and subjective health rating. The relationship is of value as it may help evaluate the impact of TBI on patients’ lives and facilitate the delivery of appropriate neuro-rehabilitation services. Methods A single-centre retrospective study was undertaken to assess the relationship between physical outcome as measured by GOSE and quality of life captured by the SF-36 questionnaire. Cronbach’s alpha was calculated for each of the eight SF-36 domains to measure internal consistency of the test. Multivariate analysis of variance was conducted to look at the association between GOSE and the physical (PCS) and mental (MCS) component scores on the SF-36. Finally, we performed a generalised linear mixed model (GLMM) to assess the relative contribution of GOSE score, age at the time of trauma, sex and TBI duration towards MCS and PCS rating. Results There is a statistically significant difference in the MCS and PCS scores based on patients’ GOSE scores. The mean scores of the eight SF-36 domains showed significant association with GOSE. GLMM demonstrated that GOSE was the strongest predictor of PCS and MCS. Age was an important variable in the PCS score while time following trauma was a significant predictor of MCS rating. Conclusions This study highlights that patients’ physical outcome following TBI is a strong predictor of the subjective mental and physical health. Nevertheless, there remains tremendous variability in individual SF-36 scores for each GOSE category, highlighting that additional factors play a role in determining quality of life.

The article aims to highlight Russian approaches to Chinese One Belt-One Road initiative. It examines possible opportunities and challenges for co-development of the Eurasian Economic Union and the Belt project. Both projects and their co-development may reduce the uncertainty in Eurasia, caused by significant structural changes in international relations and the world economy, the emergence of new trade regimes and the erosion of leadership in international affairs. Russian interests in this regard are determined by the need for modernization and long-term development, which could also help to address acute security issues. These particular factors encouraged Russia to come up with an ambitious plan of the Extensive Eurasian Partnership, although the prospects of its implementation currently are uncertain. The present article argues that the success of Russia-China collaboration in Eurasia will depend crucially on the future dynamics of the Eurasian integration, as well as on the agreement to co-develop the Eurasian Economic Union and the Belt Initiative with concrete and mutually beneficial projects.