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We investigate the dynamic volatility connectedness of geopolitical risk, stocks, bonds, bitcoin, gold, and oil from January 2018 to April 2022 in this study. We look at connectivity during the Pre-COVID, COVID, and Russian-Ukraine war subsamples. During the COVID-19 and Russian-Ukraine war periods, we find that conventional, Islamic, and sustainable stock indices are net volatility transmitters, whereas gold, US bonds, GPR, oil, and bitcoin are net volatility receivers. During the Russian-Ukraine war, the commodity index (DJCI) shifted from being a net recipient of volatility to a net transmitter of volatility. Furthermore, we discover that bilateral intercorrelations are strong within stock indices (DJWI, DJIM, and DJSI) but weak across all other financial assets. Our study has important implications for policymakers, regulators, investors, and financial market participants who want to improve their existing strategies for avoiding financial losses.
Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Ouro , Ucrânia , Junções Comunicantes , Federação Russa/epidemiologiaRESUMO
The current study aims to investigate how index returns of conventional and shariah indices of the USA, Europe, and Asia are affected by changes in oil prices, gold prices, VIX, gold-VIX, and oil-VIX. In our investigation, we used the S&P 500, S&P Europe 350, S&P Pan Asia, and their relevant shariah counterparts for the USA, Europe, and Asia. To examine how the explanatory factors affect the overall distribution of the explained variables, we used OLS and quantile regression. For the time frame prior to Covid-19, we discover that all volatility indices-OVX, GVZ, and VIX-influence returns of all indices simultaneously, and that all variables-aside from the spot price of oil-have a greater impact during the bear phase according to QR findings. Further, Volatility indices have a greater impact on volatility of index returns during the Covid-19 period. This is largely because the Covid-19 outbreak had a rapid impact on economies all around the world, and the only thing that affected financial markets consistently was high volatility. This is further supported by the findings of BEKK, which demonstrate that volatility extends across all markets and originates from commodities like gold, oil, gold-VIX, and VIX. Evidence for this can be seen in the fact that during the COVID-19 period, stock prices reacted more favorably to oil price volatility than to oil spot prices, which even went negative on April 20, 2020. Because of this, market stability can be promoted by reducing volatility through the prompt dissemination of crucial information, even while governments have little direct control over the prices of significant commodities like gold and crude oil.
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Absorbent polymers or hydrogel polymer materials have an enhanced water retention capacity and are widely used in agriculture and medicine. The controlled release of bioactive molecules (especially drug proteins) by hydrogels and the encapsulation of living cells are some of the active areas of drug discovery research. Hydrogel-based delivery systems may result in a therapeutically advantageous outcome for drug delivery. They can provide various sequential therapeutic agents including macromolecular drugs, small molecule drugs, and cells to control the release of molecules. Due to their controllable degradability, ability to protect unstable drugs from degradation and flexible physical properties, hydrogels can be used as a platform in which various chemical and physical interactions with encapsulated drugs for controlled release in the system can be studied. Practically, hydrogels that possess biodegradable properties have aroused greater interest in drug delivery systems. The original three-dimensional structure gets broken down into non-toxic substances, thus confirming the excellent biocompatibility of the gel. Chemical crosslinking is a resource-rich method for forming hydrogels with excellent mechanical strength. But in some cases the crosslinker used in the synthesis of the hydrogels may cause some toxicity. However, the physically cross-linked hydrogel preparative method is an alternative solution to overcome the toxicity of cross-linkers. Hydrogels that are responsive to stimuli formed from various natural and synthetic polymers can show significant changes in their properties under external stimuli such as temperature, pH, light, ion changes, and redox potential. Stimulus-responsive hydrogels have a wider range of applications in biomedicine including drug delivery, gene delivery and tissue regeneration. Stimulus-responsive hydrogels loaded with multiple drugs show controlled and sustained drug release and can act as drug carriers. By integrating stimulus-responsive hydrogels, such as those with improved thermal responsiveness, pH responsiveness and dual responsiveness, into textile materials, advanced functions can be imparted to the textile materials, thereby improving the moisture and water retention performance, environmental responsiveness, aesthetic appeal, display and comfort of textiles. This review explores the stimuli-responsive hydrogels in drug delivery systems and examines super adsorbent hydrogels and their application in the field of agriculture.
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Agricultura/métodos , Preparações de Ação Retardada/química , Hidrogéis/química , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/classificação , Hidrogéis/síntese química , Hidrogéis/classificação , Concentração de Íons de Hidrogênio , Oxirredução , Polímeros/química , Materiais Inteligentes/síntese química , Materiais Inteligentes/química , Materiais Inteligentes/classificação , Temperatura , Água/químicaRESUMO
Maori are the indigenous people of New Zealand, and suffer disparate health outcomes compared to non-Maori. Waikato District Health Board provides level III intensive care unit services to New Zealand's Midland region. In 2016, our institution formalised a corporate strategy to eliminate health inequities for Maori. Our study aimed to describe Maori health outcomes in our intensive care unit and identify inequities. We performed a retrospective audit of prospectively entered data in the Australian and New Zealand Intensive Care Society database for all general intensive care unit admissions over 15 years of age to Waikato Hospital from 2014 to 2018 (n = 3009). Primary outcomes were in-intensive care unit and in-hospital mortality. The secondary outcome was one-year mortality. In our study, Maori were over-represented relative to the general population. Compared to non-Maori, Maori patients were younger (51 versus 61 years, P < 0.001), and were more likely to reside outside of the Waikato region (37.2% versus 28.0%, P < 0.001) and in areas of higher deprivation (P < 0.001). Maori had higher admission rates for trauma and sepsis (P < 0.001 overall) and required more renal replacement therapy (P < 0.001). There was no difference in crude and adjusted mortality in-intensive care unit (16.8% versus 16.5%, P = 0.853; adjusted odds ratio 0.98 (95% confidence interval 0.68 to 1.40)) or in-hospital (23.7% versus 25.7%, P = 0.269; adjusted odds ratio 0.84 (95% confidence interval 0.60 to 1.18)). One-year mortality was similar (26.1% versus 27.1%, P=0.6823). Our study found significant ethnic inequity in the intensive care unit for Maori, who require more renal replacement therapy and are over-represented in admissions, especially for trauma and sepsis. These findings suggest upstream factors increasing Maori risk for critical illness. There was no difference in mortality outcomes.