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Refereed/Peer-reviewed This paper examines the time-frequency spillovers and connectedness between the major precious metals futures markets (gold, palladium, platinum, and silver), the West Texas Intermediate (WTI) oil futures, the US stock market, the US 10-year Treasury Bond (T-Bond) market, and the US dollar index. Applying Barunik and Krehlik's (2018) novel framework, the results show that spillovers across markets strengthens in the short-term, suggesting that diversification opportunities are lower in the short-term than the long-term. Furthermore, we find that the net transmitter/receiver of spillover is dependent on the frequency being analyzed, thereby indicating asymmetric spillovers among markets. Moreover, gold and silver (platinum, T-Bonds, and US dollar index) are net transmitters (receivers) of spillover regardless of the time horizon. Palladium is the net transmitter of spillover to the other markets in the short-term period (1–8 days); in contrast, in the long-term period (8–256 days), the S&P 500 index is the net transmitter of spillover. Precious metals futures, crude oil, and T-Bond assets are diversifiers for the US stock market for short-term and the long-term investments. The US dollar index is a strong hedge regardless of the time horizon and a strong (weak) safe haven asset in the short (long) term. Precious metals are a safe haven in the short-term and long-term periods. Crude oil and T-Bonds are not a safe haven for US equity investors. Finally, our result support evidence of diversification benefits and better hedging effectiveness by adding precious metals, WTI, T-Bond, and USDX to S&P500 index, which is higher in the long-term than in the short-term. WTI offers the highest hedging effectiveness, regardless the time investment horizons.

Purpose This study aims to examine the multiscale predictability power of COVID-19 deaths and confirmed cases on the S&P 500 index (USA), CAC30 index (France), BSE index (India), two strategic commodity futures (West Texas intermediate [WTI] crude oil and Gold) and five main uncertainty indices Equity Market Volatility Ticker (EMV), CBOE Volatility Index (VIX), US Economic Policy Uncertainty (EPU), CBOE Crude Oil Volatility Index (OVX) and CBOE ETF Gold Volatility Index (GVZ). Furthermore, the authors analyze the impact of uncertainty indices and COVID-19 deaths and confirmed cases on the price returns of stocks (S&P500, CAC300 and BSE), crude oil and gold. Design/methodology/approach The authors used the wavelet coherency method and quantile regression approach to achieve the objectives. Findings The results show strong multiscale comovements between the variables under investigation. Lead-lag relationships vary across frequencies. Finally, COVID-19 news is a powerful predictor of the uncertainty indices at intermediate (4–16 days) and low (32–64 days) frequencies for EPU and at low frequency for EMV, VIX, OVX and GVZ indices from January to April 2020. The S&P500, CAC30 and BSE indexes and gold prices comove with COVID-19 news at low frequencies during the sample period. By contrast, COVID-19 news and WTI oil moderately correlated at low frequencies. Finally, the returns on equity and commodity assets are influenced by uncertainty indices and are sensitive to market conditions. Originality/value This study contributes to the literature by exploring the time and frequency dependence between COVID-19 news (confirmed and death cases) on the returns of financial and commodity markets and uncertainty indexes. The findings can assist market participants and policymakers in considering the predictability of future prices and uncertainty over time and across frequencies when setting up regulations that aim to enhance market efficiency.

This paper examines frequency dynamic spillovers in return and volatility and the hedging ability of Green Bonds, gold, silver, oil, the US dollar index, and volatility index against downside US stock prices before and during the COVID-19 pandemic outbreak and for the short and long run. To do so, we use the Diebold and Yilmaz (2014), the TVP-VAR model, and the frequency spillover index by Baruník and Křehlík (2018). We show that the short-term volatility spillovers dominate their long-term counterparts. Green Bond is net transmitters of spillovers in the system at the short term and net receivers at the long term. SP500 and silver (USDX and oil) are net transmitters (receivers) of short- and long-term spillovers. Gold and VIX are net receivers of short-term spillovers and net transmitters of long-term spillovers. COVID-19 crisis has more effects on the short-term spillover, which reaches its highest level early 2020. COVID-19 and time horizons lead the direction and the magnitude of spillovers. The Quantile-on-Quantile regression analysis shows significant nonlinear relationships between markets under study. More interestingly, we show that green bonds and gold are safe haven assets for US equity investors during COVID-19. On the other hand, a mixed portfolio offers higher diversification benefits. Finally, hedging effectiveness is dependent on COVID-19 and time horizon.

This study investigates tail dependence among five major cryptocurrencies, namely Bitcoin, Ethereum, Litecoin, Ripple, and Bitcoin Cash, and uncertainties in the gold, oil, and equity markets. Using the cross-quantilogram method and quantile connectedness approach, we identify cross-quantile interdependence between the analyzed variables. Our results show that the spillover between cryptocurrencies and volatility indices for the major traditional markets varies substantially across quantiles, implying that diversification benefits for these assets may differ widely across normal and extreme market conditions. Under normal market conditions, the total connectedness index is moderate and falls below the elevated values observed under bearish and bullish market conditions. Moreover, we show that under all market conditions, cryptocurrencies have a leadership influence over the volatility indices. Our results have important policy implications for enhancing financial stability and deliver valuable insights for deploying volatility-based financial instruments that can potentially provide cryptocurrency investors with suitable hedges, as we show that cryptocurrency and volatility markets are insignificantly (weakly) connected under normal (extreme) market conditions.

This paper examines return spillovers within and between different DeFi, cryptocurrency, stock, and safe-haven assets. For the period January 2019 to March 2022, we find that DeFi and cryptocurrency asset markets exhibit strong within-market and between-market return spillovers, that stock and safe-haven markets show weak connectedness, and that safe-haven assets are minor receivers and transmitters of between-market spillover effects. The connectedness between markets is time-varying and reveals structural changes in early 2020. Furthermore, we document that financial conditions shape the dynamics of return spillover effects between markets We would like to thank two anonymous reviewers for constructive and insightful comments. Juan C. Reboredo acknowledges financial support provided by the Agencia Estatal de Investigación (Ministerio de Ciencia, Innovación y Universidades) under research project with reference PID2021–124336OB-I00 co-funded by the European Regional Development Fund (ERDF/FEDER) SI

PurposeThis study aims to examine the tail connectedness between the Chinese and Association of Southeast Asian Nations (ASEAN) stock markets. More specifically, the authors measure the return spillovers at three quantile levels: median (t = 0.5), lower extreme (t = 0.05) and upper extreme (t = 0.95). The connectedness at extreme upper and lower quantiles provides insightful information to investors regarding tail risk propagation, which ultimately suggests that investors adjust their portfolios according to the extreme bullish and bearish market conditions.Design/methodology/approachThe authors employ the quantile connectedness approach of Andoet al.(2022) to examine the quantile transmission mechanism among the ASEAN and Chinese stock markets.FindingsThe results show significant evidence of a higher level of connectedness between Chinese and ASEAN stock markets at extreme upper and lower quantiles compared to the median quantiles, which suggests the use of a quantile-based connectedness approach instead of an average-measure-based one. Furthermore, the time-varying connectedness analysis shows that the total spillovers reach the highest peaks during the global financial crisis, the Chinese stock market crash and the COVID-19 pandemic at the upper, lower and median quantiles. Finally, the static and dynamic pairwise spillovers between the Chinese and ASEAN markets vary over quantiles as well.Originality/valueThis study is the first attempt to examine quantile vector autoregression (VAR)-based return spillovers between China and ASEAN stock markets during different market statuses. Besides, the COVID-19 has intensified the uncertainty in Asian countries, mainly China and ASEAN economies.

Enhancing the kinetics of liquid-vapor transition from nanoscale confinements is an attractive strategy for developing evaporation and separation applications. The ultimate limit of confinement for evaporation is an atom thick interface hosting angstrom-scale nanopores. Herein, using a combined experimental/computational approach, we report highly enhanced water evaporation rates when angstrom sized oxygen-functionalized graphene nanopores are placed at the liquid-vapor interface. The evaporation flux increases for the smaller nanopores with an enhancement up to 35-fold with respect to the bare liquid-vapor interface. Molecular dynamics simulations reveal that oxygen-functionalized nanopores render rapid rotational and translational dynamics to the water molecules due to a reduced and short-lived water-water hydrogen bonding. The potential of mean force (PMF) reveals that the free energy barrier for water evaporation decreases in the presence of nanopores at the atomically thin interface, which further explains the enhancement in evaporation flux. These findings can enable the development of energy-efficient technologies relying on water evaporation.

SSc is an auto-immune disease characterized by life-threatening manifestations such as lung fibrosis or pulmonary arterial hypertension. Symptoms with a detrimental impact on quality of life are also reported and sicca syndrome (xerostomia, xeropthalmia) is present in up to 80% of patients with SSc. Sicca syndrome can occur in the absence of overlap with Sjögren’s disease and recent studies highlight that fibrosis of minor and major salivary glands, directly linked to the pathogenesis of SSc, could be a major contributor of xerostomia in SSc. This narrative review provides an overview of the clinical presentation, diagnostic strategies, management and future perspectives on sicca syndrome in patients with SSc.

In many research contexts, especially in the biomedical field, after studying and developing a classification system a natural question arises: "Is this accuracy enough high?", or better, "Can we say, with a statistically significant confidence, that our classification system is able to solve the problem"? To answer to this question, we can use the statistical test described in this paper, which is referred in some cases as NIR (No Information Rate or Null Information Rate).

The development of stable materials, processable on alarge area,is a prerequisite for perovskite industrialization. Beyond the perovskiteabsorber itself, this should also guide the development of all otherlayers in the solar cell. In this regard, the use of NiO x as a hole transport material (HTM) offers severaladvantages, as it can be deposited with high throughput on large areasand on flat or textured surfaces via sputtering, a well-establishedindustrial method. However, NiO x may triggerthe degradation of perovskite solar cells (PSCs) when exposed to environmentalstressors. Already after 100 h of damp heat stressing, a strong fillfactor (FF) loss appears in conjunction with a characteristic S-shaped J-V curve. By performing a wide range of analysison cells and materials, completed by device simulation, the causeof the degradation is pinpointed and mitigation strategies are proposed.When NiO x is heated in an air-tight environment,its free charge carrier density drops, resulting in a band misalignmentat the NiO x /perovskite interface and inthe formation of a barrier impeding hole extraction. Adding an organiclayer between the NiO x and the perovskiteenables higher performances but not long-term thermal stability, forwhich reducing the NiO x thickness is necessary.

The access to basic healthcare for people who are not registered in the national health system is nowadays a very urgent problem, both in Italy and in the rest of the world. Immigration and poverty are only some of the factors that make one of the primary rights of humanity—healthcare—not a right for everyone. The main problems, which have grown exponentially in the last decade, are at operational level, due to the lack of personnel (mostly volunteers) and the lack of spaces. This paper illustrates procedures and techniques for the design of a small emergency structure that can be moved and positioned in urban contexts. The first part consists of a deep analysis of the problem and of the state of the art of existing typologies. The second part is dedicated to the conceptual framework (requirements, conceptual model) and to the definition of the preliminary design for the new approach to basic non-conventional sanitary spaces. Finally, a virtual case study (project application) in Italy is presented.

Notwithstanding the ban in 1992, asbestos exposure for workers in the construction sector in Italy remains a concern. The purpose of this study is to describe the characteristics of malignant mesothelioma (MM) cases recorded by the Italian registry (ReNaM) among construction workers. Incident mesothelioma cases with a definite asbestos exposure have been analyzed. Characteristics of cases and territorial clusters of crude rates of MM in construction workers have been described, as well as the relation between asbestos use before the ban and the historical trend of workforce in the construction sector in Italy. ReNaM has collected 31,572 incident MM cases in the period from 1993 to 2018 and asbestos exposure has been assessed for 24,864 (78.2%) cases. An occupational exposure has been reported for 17,191 MM cases (69.1% of subjects with a definite asbestos exposure). Among them, 3574 had worked in the construction sector, with an increasing trend from 15.8% in the 1993–98 period to 23.9% in 2014–2018 and a ubiquitous territorial distribution. The large use of asbestos in construction sector before the ban makes probability of exposure for workers a real concern still today, particularly for those working in maintenance and removal of old buildings. There is a clear need to assess, inform, and prevent asbestos exposure in this sector.

Accurate prognostication of individuals at clinical high-risk for psychosis (CHR-P) is an essential initial step for effective primary indicated prevention. We aimed to summarise the prognostic accuracy and clinical utility of CHR-P assessments for primary indicated psychosis prevention. Web of Knowledge databases were searched until 1st January 2022 for longitudinal studies following-up individuals undergoing a psychometric or diagnostic CHR-P assessment, reporting transition to psychotic disorders in both those who meet CHR-P criteria (CHR-P + ) or not (CHR-P−). Prognostic accuracy meta-analysis was conducted following relevant guidelines. Primary outcome was prognostic accuracy, indexed by area-under-the-curve (AUC), sensitivity and specificity, estimated by the number of true positives, false positives, false negatives and true negatives at the longest available follow-up time. Clinical utility analyses included: likelihood ratios, Fagan’s nomogram, and population-level preventive capacity (Population Attributable Fraction, PAF). A total of 22 studies (n = 4 966, 47.5% female, age range 12–40) were included. There were not enough meta-analysable studies on CHR-P diagnostic criteria (DSM-5 Attenuated Psychosis Syndrome) or non-clinical samples. Prognostic accuracy of CHR-P psychometric instruments in clinical samples (individuals referred to CHR-P services or diagnosed with 22q.11.2 deletion syndrome) was excellent: AUC = 0.85 (95% CI: 0.81–0.88) at a mean follow-up time of 34 months. This result was driven by outstanding sensitivity (0.93, 95% CI: 0.87–0.96) and poor specificity (0.58, 95% CI: 0.50–0.66). Being CHR-P + was associated with a small likelihood ratio LR + (2.17, 95% CI: 1.81–2.60) for developing psychosis. Being CHR-P- was associated with a large LR- (0.11, 95%CI: 0.06−0.21) for developing psychosis. Fagan’s nomogram indicated a low positive (0.0017%) and negative (0.0001%) post-test risk in non-clinical general population samples. The PAF of the CHR-P state is 10.9% (95% CI: 4.1–25.5%). These findings consolidate the use of psychometric instruments for CHR-P in clinical samples for primary indicated prevention of psychosis. Future research should improve the ability to rule in psychosis risk.

This study examines the volatility spillovers between the US stock market (SP500 index) and both oil and gold before and during the global health crisis (GHC). We apply the FIAPARCH-DCC model to the 15-minute intraday data. The results showed negative (positive) conditional correlations between the SP500 and gold (oil). The time-varying conditional correlations between markets were higher during COVID-19 spread. Moreover, gold offers more diversification gains than oil does during the pandemic. Hedging is more expensive during a pandemic than before. Oil provides higher hedging effectiveness (HE) than gold for all sub-periods. HE was lower during the COVID-19 outbreak for both oil and gold. These findings have important implications for both equity investors and policymakers.

Objectives: The purposes of this study are to describe the epidemiology of pericardial and tunica vaginalis testis mesothelioma and assess the role of asbestos exposure for these rare diseases. Methods: Based on incident pericardial and tunica vaginalis testis mesothelioma cases collected from the Italian national mesothelioma registry (ReNaM) in the period 1993–2015, incidence rates, survival median period and prognostic factors have been evaluated. A case–control study has been performed to analyze the association with asbestos exposure (occupational and non-occupational) for these diseases. Results: Between 1993 and 2015, 58 pericardial (20 women and 38 men) and 80 tunica vaginalis testis mesothelioma cases have been registered with a mean annual standardized (world standard population as reference) incidence rates of 0.049 (per million) in men and 0.023 in women for the pericardial site, and 0.095 for tunica vaginalis testis mesothelioma. Occupational exposure to asbestos was significantly associated with the risk of the diseases [odds ratio (OR) 3.68, 95% confidence interval (CI) 1.85–7.31 and OR 3.42, 95% CI 1.93–6.04 in pericardial and tunica vaginalis testis mesothelioma, respectively]. The median survival was 2.5 months for pericardial and 33.0 months for tunica vaginalis testis mesotheliomas. Age was the main predictive factor for survival for both anatomical sites. Conclusions: For the first time in an analytical study, asbestos exposure was associated with pericardial and tunica vaginalis testis mesothelioma risk, supporting the causal role of asbestos for all anatomical sites. The extreme rarity of the diseases, the poor survival and the prognostic role of age have been confirmed based on population and nationwide mesothelioma registry data.

Background The European impact of the clinical high risk for psychosis (CHR-P) paradigm is constrained by the lack of critical mass (detection) to power prognostic and preventive interventions. Methods An ITAlian partnership for psychosis prevention (ITAPP) was created across CHR-P centers, which were surveyed to describe: (a) service, catchment area, and outreach; (b) service users; and (c) interventions and outcomes. Descriptive statistics and Kaplan-Meier failure function complemented the analyses. Results The ITAPP included five CHR-P clinical academic centers established from 2007 to 2018, serving about 13 million inhabitants, with a recruitment capacity of 277 CHR-P individuals (mean age: 18.7 years, SD: 4.8, range: 12-39 years; 53.1% females; 85.7% meeting attenuated psychotic symptoms; 85.8% without any substance abuse). All centers were multidisciplinary and included adolescents and young adults (transitional) primarily recruited through healthcare services. The comprehensive assessment of at-risk mental state was the most widely used instrument, while the duration of follow-up, type of outreach, and preventive interventions were heterogeneous. Across 205 CHR-P individuals with follow up (663.7 days ± 551.7), the cumulative risk of psychosis increased from 8.7% (95% CI 5.3-14.1) at 1 year to 15.9% (95% CI 10.6-23.3) at 2 years, 21.8% (95% CI 14.9-31.3) at 3 years, 34.8% (95% CI 24.5-47.9) at 4 years, and 51.9% (95% CI 36.3-69.6) at 5 years. Conclusions The ITAPP is one of the few CHR-P clinical research partnerships in Europe for fostering detection, prognosis, and preventive care, as well as for translating research innovations into practice.

This paper examines the frequency of spillovers between crude oil futures and the Middle East and North Africa (MENA) stock markets. We use the methodologies proposed by Diebold and Yilmaz (2012) and Baruník and Křehlík (2018) and the wavelet coherency approach. The results show time-varying volatility spillovers in the considered markets. The short-term spillovers are higher than their intermediate-term counterparts. The highest jump in spillovers occurs during the COVID-19 outbreak, followed by the global financial crisis and the recent oil price crash. The spillovers are higher for oil-exporting countries than oil-importing countries. Saudi Arabia, Qatar, and the United Arab Emirates (UAE) are the main contributors to spillovers in the short and intermediate terms. Brent oil, Egypt, Morocco, and Turkey are the net receivers of spillovers in the short term, and they switch to become net contributors to spillovers in the intermediate term. Turkey and oil-exporting stock markets receive more spillovers than oil-importing stock markets irrespective of the time frequency. Wavelet analysis shows evidence of co-movements between oil futures and stock markets at intermediate and low frequencies. The lead–lag relationships between crude oil and stock markets are mixed and time-varying. Moreover, a mixed portfolio offers diversification benefits. Hedging is more expensive during the pandemic period and particularly in the intermediate term compared to the short term. Hedging effectiveness is highest during the COVID-19 pandemic in the short and intermediate terms for almost all markets. Refereed/Peer-reviewed

This paper examines the volatility transmission between crude oil and four precious metals (i.e., gold, silver, platinum, and palladium) and investigates whether oil can be considered as a hedge or safe-haven asset against four precious metals. Our empirical analysis reveals several important findings. First, we determine that the volatility transmission was time-varying and that influence from the Asian crisis, the bursting of the dot-com bubble, the 2008 global financial crisis, the recent oil-price crash, and COVID-19 alternated between negative and positive values over the entire studied period. We further conclude that Brent oil is a diversifier and a weak safe haven for precious metals; and thus, that a combined portfolio composed of Brent-oil and precious-metals futures yields better hedging effectiveness. These findings indicate that oil futures are a useful investment that reduces downside risks and strengthens diversification benefits in portfolio risk management. Refereed/Peer-reviewed

Background: Due to high purity, recombinant human chorionic gonadotropin (hCG) is suitable for subcutaneous injection, and hence for self-administration, in assisted reproduction. To increase usability and reduce the risk of dosing errors, a prefilled pen was produced. We investigated the ease of administration and satisfaction with the product amongst patients and healthcare professionals. Methods: A survey was conducted amongst women with infertility who underwent in vitro fertilization treatments with recombinant hCG to trigger ovulation in various clinics in Italy. Results: A total of 276 Italian women were interviewed. The median score of preference for the prefilled pen in comparison with hCG powder to be reconstituted in the solvent was rated as 9 (range 8–10), and 125 women answered that the prefilled pen had major advantages. Reasons for preference of the prefilled pen were linked to ease of use and safety: avoidance of dosage mistakes and of concern of such, ease of administration, certainty that the drug is correctly taken, safe administration and no anxiety. The procedure for recombinant hCG administration through the prefilled pen was judged as easy by 80% of respondents, with a median score of 9 (range 8–10) for easiness on a 1–10 scale. Out of 276 respondents, 249 (90%) had no problem with the injection. Conclusion: Overall, the respondents reported a favourable perception of the prefilled pen with hCG, which was reported to be easy to use and perceived to prevent dosage mistakes.

A new MOF with a saturated N-heterocyclic carbene ligand undergoes a series of structural transformations to produce a turbostratic material, which serves as a better support for an iridium hydrogenation catalyst, when compared to the parent material.

Background GLUT1 deficiency syndrome is a rare, genetically determined neurological disorder for which Ketogenic Dietary Treatment represents the gold standard and lifelong treatment. Patient registries are powerful tools providing insights and real-world data on rare diseases. Objective To describe the implementation of a national web-based registry for GLUT1-DS. Methods This is a retrospective and prospective, multicenter, observational registry developed in collaboration with the Italian GLUT1-DS association and based on an innovative, flexible and configurable cloud computing technology platform, structured according to the most rigorous requirements for the management of patient’s sensitive data. The Glut1 Registry collects baseline and follow-up data on the patient’s demographics, history, symptoms, genotype, clinical, and instrumental evaluations and therapies. Results Five Centers in Italy joined the registry, and two more Centers are currently joining. In the first two years of running, data from 67 patients (40 females and 27 males) have been collected. Age at symptom onset was within the first year of life in most (40, 60%) patients. The diagnosis was formulated in infancy in almost half of the cases (34, 51%). Symptoms at onset were mainly paroxysmal (mostly epileptic seizure and paroxysmal ocular movement disorder) or mixed paroxysmal and fixed symptoms (mostly psychomotor delay). Most patients (53, 79%) are currently under Ketogenic dietary treatments. Conclusions We describe the principles behind the design, development, and deployment of the web-based nationwide GLUT1-DS registry. It represents a stepping stone towards a more comprehensive understanding of the disease from onset to adulthood. It also represents a virtuous model from a technical, legal, and organizational point of view, thus representing a possible paradigmatic example for other rare disease registry implementation.

Life events (traumatic and protective) may be critical factors associated with eating disorders and their severity. To date, there is little literature concerning the role of life events in adolescence. The main goal of this study was to explore in a sample of adolescent patients with restrictive eating disorders (REDs) the presence of life events in the year before enrolment and to characterize them according to timing. Furthermore, we investigated correlations between REDs severity and the presence of life events. In total, 33 adolescents completed the EDI-3 questionnaire to assess RED severity using EDRC (Eating Disorder Risk Composite), GPMC (General Psychological Maladjustment Composite), and the Coddington Life Events Scales—Adolescent (CLES-A) questionnaires to define the presence of life events in the last year. Of these, 87.88% reported a life event in the past year. A significant association emerged between elevated clinical GPMC and the presence of traumatic events: patients who had experienced at least one traumatic life event in the year before enrolment presented higher clinically elevated GPMC compared to patients who had not. These results suggest that obtaining early information about traumatic events in clinical practice may help prevent the occurrence of new events and improve patient outcomes.

This study addresses whether gold exhibits the function of a hedge or safe haven as often referred to in academia. It contributes to the existing literature by (i) revisiting this question for the principal stock markets in the Middle East and North Africa (MENA) region and (ii) using the copula-quantile-on-quantile and conditional value at risk methods to detail the risks facing market participants provided with accurate information about various gold and stock market scenarios (i.e., bear, normal, bull). The results provide strong evidence of quantile dependence between gold and stock returns. Positive correlations are found between MENA gold and stock markets when both are bullish. Conversely, when stock returns are bearish, gold markets show negative correlations with MENA stock markets. The risk spillover from gold to stock markets intensified during the global financial and European crises. Given the risk spillover between gold and stock markets, investors in MENA markets should be careful when considering gold as a safe haven because its effectiveness as a hedge is not the same in all MENA stock markets. Investors and portfolio managers should rebalance their portfolio compositions under various gold and stock market conditions. Overall, such precise insights about the heterogeneous linkages and spillovers between gold and MENA stock returns provide potential input for developing effective hedging strategies and optimal portfolio allocations.

PurposeThis paper examines the extreme dependence and asymmetric risk spillovers between crude oil futures and ten US stock sector indices (consumer discretionary, consumer staples, energy, financials, health care, industrials, information technology, materials, telecommunication and utilities) before and during COVID-19 outbreak. This study is based on the rationale that stock sectors exhibit heterogeneity in their response to oil prices depending on whether they are classified as oil-intensive or non-oil-intensive sectors and the possible time variation in the dependence and risk spillover effects.Design/methodology/approachThe authors employ static and dynamic symmetric and asymmetric copula models as well as Conditional Value at Risk (VaR) (CoVaR). Finally, they use robustness tests to validate their results.FindingsBefore the COVID-19 pandemic, crude oil returns showed an asymmetric tail dependence with all stock sector returns, except health care and industrials (materials), where an average (symmetric tail) dependence is identified. During the COVID-19 pandemic, crude oil returns exhibit a lower tail dependency with the returns of all stock sectors, except financials and consumer discretionary. Furthermore, there is evidence of downside and upside risk asymmetric spillovers from crude oil to stock sectors and vice versa. Finally, the risk spillovers from stock sectors to crude oil are higher than those from crude oil to stock sectors, and they significantly increase during the pandemic.Originality/valueThere is heterogeneity in the linkages and the asymmetric bidirectional systemic risk between crude oil and US economic sectors during bearish and bullish market conditions; this study is the first to investigate the average and extreme tail dependence and asymmetric spillovers between crude oil and US stock sectors.

Background Once psychosis has set in, it is difficult for patients to achieve full recovery. Prevention of psychosis and early intervention are promising for improving the outcomes of this disorder. In the last two decades, neurocognition has been studied as a biomarker for clinical-high risk for psychosis (CHR-P). However, neurocognitive functioning has been under-investigated in adolescents. Methods We enrolled 116 adolescents from 12 to 17 years old (mean = 15.27, SD = 1.56; 76 females). This 3-year cohort study aimed to identify differences in neurocognitive and overall functioning in three groups of adolescent patients divided according to the semi-structured interview Comprehensive Assessment of At-Risk Mental States (CAARMS): adolescents with established psychosis, adolescents with CHR-P, and adolescents not meeting either criteria (non-CHR-P). To differentiate the profiles, clinicians administered cognitive evaluation and neuropsychological tasks. Moreover, they filled in scales to assess their global, social, and role functioning and a questionnaire to assess the severity of the disease. Results We made a between-group comparison on neurocognitive measures and found that the CHR-P and the psychosis groups differed in processing speed (TMT-A; p = .002 in BVN categorial fluency (p = .018), and Rey–Osterrieth complex figure drawing from memory task (p = .014), with psychosis group showing worse performance. No differences emerged between non-CHR-P and CHR-P (p = .014) individuals. CHR-P had better functioning than the psychosis group but worse than the non-CHR-P one. Conclusions These results confirm that neurocognition can be a helpful biomarker in identifying specific subgroups of adolescents with emerging psychopathology and help clinicians develop stratified preventive approaches.

The quality of family interactions may be a critical factor for restrictive eating disorders (REDs). Adolescent patients with RED have interpersonal problems that can be inferred by observing their behaviours during family interactions. To date, the assessment of the association among RED severity, interpersonal problems, and patients’ interactive behaviours in the family is partially explored. This cross-sectional study aimed to explore how adolescent patients’ interactive behaviours observed during the Lausanne Trilogue Play—clinical version (LTPc) were associated with both RED severity and interpersonal problems. Sixty adolescent patients completed the EDI-3 questionnaire to assess RED severity using the Eating Disorder Risk Composite (EDRC) and Interpersonal Problems Composite (IPC) subscales. Moreover, patients and their parents took part in the LTPc, and patients’ interactive behaviours were coded as participation, organization, focal attention, and affective contact in all the LTPc four phases. A significant association emerged between patients’ interactive behaviours during the LTPc triadic phase and both EDRC and IPC. Better patients’ organization and affective contact significantly correlated with lower RED severity and fewer interpersonal problems. These findings suggest that investigating the quality of family relationships and patients’ interactive behaviours may contribute to better identifying adolescent patients at risk for more severe conditions.

This study estimates the effects of the dual long memory property and structural breaks on the persistence level of six major cryptocurrency markets. We apply the Bai and Perron structural break test, Inclán and Tiao’s iterated cumulative sum of squares (ICSS) algorithm, and the fractionally integrated generalized autoregressive conditional heteroscedasticity (FIGARCH) model, with different distributions. The results show that long memory and structural breaks characterize the conditional volatility of cryptocurrency markets, confirming our hypothesis that ignoring structural breaks leads to an underestimation of the persistence of volatility modeling. The ARFIMA-FIGARCH model, with structural breaks and a skewed Student-t distribution, fits the cryptocurrency market’s price dynamics well.

Fluorination of ether solvents is an effective strategy to improve the electrochemical stability of non-aqueous electrolyte solutions in lithium metal batteries. However, excessive fluorination detrimentally impacts the ionic conductivity of the electrolyte, thus limiting the battery performance. Here, to maximize the electrolyte ionic conductivity and electrochemical stability, we introduce the targeted trifluoromethylation of 1,2-dimethoxyethane to produce 1,1,1-trifluoro-2,3-dimethoxypropane (TFDMP). TFDMP is used as a solvent to prepare a 2 M non-aqueous electrolyte solution comprising bis(fluorosulfonyl)imide salt. This electrolyte solution shows an ionic conductivity of 7.4 mS cm–1 at 25 °C, an oxidation stability up to 4.8 V and an efficient suppression of Al corrosion. When tested in a coin cell configuration at 25 °C using a 20 μm Li metal negative electrode, a high mass loading LiNi0.8Co0.1Mn0.1O2-based positive electrode (20 mg cm–2) with a negative/positive (N/P) capacity ratio of 1, discharge capacity retentions (calculated excluding the initial formation cycles) of 81% after 200 cycles at 0.1 A g–1 and 88% after 142 cycles at 0.2 A g–1 are achieved.

Metal halide perovskites (MHPs) have shown an incredible rise in efficiency, reaching as high as 25.7%, which now competes with traditional photovoltaic technologies. Herein, we excluded CsX and RbX, the most commonly used cations to stabilize FAPbI3, from the bulk of perovskite thin films and applied them on the surface, as passivation agents. Extensive device optimization led to a power conversion efficiency (PCE) of 24.1% with a high fill factor (FF) of 82.2% upon passivation with CsI. We investigated in-depth the effect of CsI passivation on structural and optoelectronic properties using X-ray diffraction (XRD), angle resolved X-ray photoelectron spectroscopy (ARXPS), Kelvin Probe Force (KPFM) microscopy, time-resolved photoluminescence (TRPL), photoluminescence quantum yield (PLQY) and electroabsorption spectroscopy (TREAS). Furthermore, passivated devices exhibit enhanced operational stability, with optimized passivation with CsI leading to a retention of ~90% of initial PCE under 1 Sun illumination with maximum power point tracking for 600 h., Comment: 27 pages, 19 figures

This study investigates dynamic frequency connectedness for volatility differences among eight popular cryptocurrencies (Bitcoin, Ethereum, Litecoin, Dash, Monero, Ripple, Nem and Stellar). It employs the methodologies of Diebold and Yilmaz (2014; 2016) and Barunik and Křehlik (2018). Furthermore, an analysis of diversification benefits and downside risk reductions is carried out. The results demonstrated dynamic spillovers, which intensified after 2017. Furthermore, Bitcoin, Ethereum, and Litecoin are net transmitters of risk, which can be a contagion source; Dash, Ripple, Monero, Stellar, and Nem are net receivers of risk. Moreover, the short-term risk spillover is more pronounced than the medium- and long-term risk spillovers, which also increased after 2017. The directional spillovers among cryptocurrencies is sensitive to frequencies. Finally, adding a cryptocurrency to a benchmark Bitcoin portfolio provides diversification benefits and downside risk reductions. In contrast, adding Bitcoin to a cryptocurrency portfolio do not offers diversification opportunities.

Hybrid lead halide perovskites have reached comparable efficiencies to state-of-the-art silicon solar cell technologies. However, a remaining key challenge toward commercialization is the resolution of the perovskite device instability. In this work, we identify for the first time the mobile nature of bis(trifluoromethanesulfonyl)imide (TFSI-), a typical anion extensively employed in p-type dopants for 2,2'7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'spirofluorene (spiro-OMeTAD). We demonstrate that TFSI- can migrate through the perovskite layer via the grain boundaries and accumulate at the perovskite/electron-transporting layer (ETL) interface. Our findings reveal that the migration of TFSI- enhances the device performance and stability, resulting in highly stable p-i-n cells that retain 90% of their initial performance after 1600 h of continuous testing. Our systematic study, which targeted the effect of the nature of the dopant and its concentration, also shows that TFSI- acts as a dynamic defect-healing agent, which self-passivates the perovskite crystal defects during the migration process and thereby decreases nonradiative recombination pathways.

Purpose This paper aims to examine the frequency of co-movements and asymmetric dependencies between bitcoin (BTC), gold, Brent crude oil and the US economic policy uncertainty (EPU) index. Design/methodology/approach The authors use a wavelet approach and a quantile-on-quantile regression (QQR) method. Findings The results show a positive interdependence between BTC and commodity price returns at both medium and low frequencies over the sample period. In contrast, the dependence is negative between BTC and EPU index at both medium and low frequencies. Furthermore, the co-movements between markets are more pronounced during crises. The results show that strategic commodities and EPU index have the ability to predict BTC price returns at both medium- and long-terms. The QQR method reveals that higher gold returns tend to predict higher/lower BTC returns when the market is in a bullish/bearish state. Moreover, lower gold returns tend to predict lower (higher) BTC returns when the market is in a bearish (bullish) state (positive (negative) relationship). The lower Brent returns tend to predict higher/lower BTC returns when the market is in a bullish/bearish state. High Brent quantiles tend to predict the lower BTC returns in its extremely bearish states. Finally, higher and lower EPU changes tend to predict lower and higher BTC returns when the market is in a bearish/bullish state (negative relationship). Originality/value There is generally a lack of understanding of the linkages between BTC, gold, oil and uncertainty index across multiple frequencies. This is, as far as the authors know, the first attempt to apply both the wavelet approach and a QQR method to examine the multiscale linkages among markets under study. The findings should encourage the relevant policymakers to consider these co-movements which vary over time and in duration when setting up regulations that deem to enhance the market efficiency.

Das Sammeln von Informationen über die atomare Natur von reaktiven Zentren und Fallenzuständen ist der Schlüssel zur Feinabstimmung der Katalyse und zur Unterdrückung schädlicher Oberflächenpotentialverluste in photoelektrochemischen Technologien. Hier wurden spektroelektrochemische und rechnerische Methoden kombiniert, um eine Modellphotokathode aus der vielversprechenden Chalkopyrit-Familie zu untersuchen: CuIn0.3Ga0.7S2. Es wurde festgestellt, dass Potentialverluste mit Fallen verbunden sind, die durch Oberflächen-Ga- und In-Leerstellen induziert werden, wohingegen Operando-Raman-Spektroskopie zeigte, dass Katalyse an Ga-, In- und S-Stellen stattfand. Diese Studie ermöglicht es, eine Brücke zwischen der Leistung des Chalkopyrits und seiner Oberflächenchemie zu schlagen, wobei die Vermeidung der Bildung von Ga- und In-Leerstellen entscheidend ist, um eine hohe Aktivität zu erzielen. Diese Arbeit wurde vom Schweizerischen Nationalfonds (SNF) im Rahmen des Ambizione Energy Grant (PZENP2_166871) und vom Gaznat-EPFL Forschungsprogramm unterstützt. M.B. und U.A. wurden durch die Förderungsprofessuren PP00P2_157615 und PP00P2_187185 des Schweizerischen Nationalfonds unterstützt. Die Berechnungen wurden auf UBELIX, dem HPC-Cluster der Universität Bern, durchgeführt. M.X. dankt dem China Scholarship Council (Nr. CSC201806160172) und dem Strategic Japanese–Swiss Science and Technology-Programm (514259) für die Unterstützung. Open access funding provided by Ecole Polytechnique Federale de Lausanne.

This study estimates the effects of double long memory and structural breaks on the persistence level of six major cryptocurrency markets. We apply the Bai and Perron’s structural break test, Inclán and Tiao’s iterated cumulative sum of squares (ICSS) algorithm, and the fractionally integrated generalized autoregressive conditional heteroscedasticity (FIGARCH) model with different distributions. The results show that long memory and structural breaks characterize the conditional volatility of cryptocurrency markets and confirm our hypothesis that ignoring structural breaks leads to an underestimation of the persistence of volatility modelling. The ARFIMA-FIGARCH model with structural breaks and a skewed Student–t distribution fits the cryptocurrency market’s price dynamics well.