Microhardness evaluation of root dentin after using resin sealer solvents

Background. This study aimed to assess the effects of methyl ethyl ketone (MEK) and ethyl acetate (EA) on dentin microhardness, used as resin sealer solvents. Methods. Eighty halves of single-rooted teeth were randomly divided into four groups to apply MEK, EA, chloroform, or saline solution. Vickers hardness values were measured for three root levels before and after the direct application of solvents for 5 and 15 minutes or a 1-minute application with ultrasonic agitation. The results were analyzed using repeated-measures ANOVA, and adjustments were made for comparisons with Bonferroni tests. Results. The dentin microhardness decreased in all the solvent groups (P<0.05). The changes in microhardness increased with prolonged exposure times, except for the saline solution group. Chloroform exhibited the most significant decrease in value. Furthermore, ultrasonic agitation elicited a more substantial decline in values. Conclusion. MEK and EA might be preferred over chloroform as a solvent for resin sealers because they offer an attenuated decrease in dentin microhardness and do not have gutta-percha-dissolving properties.

Executive equity incentives and opportunistic manager behavior: new evidence from a quasi-natural experiment

This study provides plausible causal evidence on the effect of executive equity incentives on opportunistic manager behavior. I exploit a unique setting created by the introduction of Financial Accounting Standard (FAS) 123R in 2005, which led to an exogenous increase in the cost of option pay, causing a substantial decline in option pay for some firms while leaving others largely unaffected. Using difference-in-differences analyses with a treatment group of firms that show a decline in option pay and two control groups, I find that the likelihood of a treatment firm meeting or beating analyst forecasts decreases by 14–20%. The results show that the relatively high levels of meet-or-beat before FAS 123R were largely driven by real activities manipulation such as abnormal asset sales and sales manipulation to beat analysts’ benchmarks, while accrual manipulation and analyst management were less relevant. Together, the results suggest that equity incentives encourage opportunistic actions to meet or beat earnings expectations, and a decline in option pay results in a decline in earnings management to meet earnings expectations.

Global and regional shock transmission: an Asian perspective

This paper constructs and uses the global input–output (GIO) table with 35 industries, 29 endogenous countries and 59 exogenous countries, and develops new indices to measure the degree of shock transmission in terms of intermediate goods and value-added embodied in production induced by negative global demand shock to finished goods. After the Global Financial Crisis (GFC) in 2008, China did not experience a large decline in economic growth, even though China’s gross exports fell most severely among Asian countries. In contrast, a sharp decrease in Japanese GDP in 2009 is a consequence of a substantial decline in finished goods exports, especially in the transport equipment industry. In Japan, the shock effect tends to be absorbed in its domestic sector and is not transmitted to other foreign countries. An asymmetric pattern of shock transmission between Japan and other Asian countries can explain why Japan was more affected by GFC than other Asian countries.

Codeine dispensing for privately insured children in the USA: a retrospective database study

In this retrospective study using claims data from the OptumLabs Data Warehouse including 24 658 769 eligible person-years of coverage in the USA, there was substantial decline in codeine dispensing between 2010 and 2019. However, we also observed a persistence of codeine prescribing despite the FDA contraindication in 2018. In 2019, codeine was still being prescribed to children aged 12–17 years at 934 prescriptions per 100 000 person-years of coverage and 106 per 100 000 person-years of coverage in children aged<12 years.

COVID Vaccine Rollout for Older Adults in Israel

The COVID vaccine rollout in Israel has prioritized older adults. It led to a substantial decline in the incidence of COVID-19 in older adults. The new variants are threats to the current achievements. We will provide detailed information later. The symposium has experts from 8 countries. We will use an interview and dialog format, instead of presentations.

COVID-19 hospital activity and in-hospital mortality during the first and second waves of the pandemic in England: an observational study

IntroductionWe aimed to examine the profile of, and outcomes for, all people hospitalised with COVID-19 across the first and second waves of the pandemic in England.MethodsThis was an exploratory retrospective analysis of observational data from the Hospital Episode Statistics data set for England. All patients aged ≥18 years in England with a diagnosis of COVID-19 who had a hospital stay that was completed between 1 March 2020 and 31 March 2021 were included. In-hospital mortality was the primary outcome of interest. The second wave was identified as starting on 1 September 2020. Multilevel logistic regression modelling was used to investigate the relationship between mortality and demographic, comorbidity and temporal covariates.ResultsOver the 13 months, 374 244 unique patients had a diagnosis of COVID-19 during a hospital stay, of whom 93 701 (25%) died in hospital. Adjusted mortality rates fell from 40%–50% in March 2020 to 11% in August 2020 before rising to 21% in January 2021 and declining steadily to March 2021. Improvements in mortality rates were less apparent in older and comorbid patients. Although mortality rates fell for all ethnic groups from the first to the second wave, declines were less pronounced for Bangladeshi, Indian, Pakistani, other Asian and black African ethnic groups.ConclusionsThere was a substantial decline in adjusted mortality rates during the early part of the first wave which was largely maintained during the second wave. The underlying reasons for consistently higher mortality risk in some ethnic groups merits further study.

Evolution of the groundwater system in the Chihuahua-Sacramento aquifer due to climatic and anthropogenic factors

Groundwater is the main source of water in arid cities where precipitations are low and not evenly distributed. The combined impact of climate variability and intensive human activities has caused a substantial decline in groundwater levels. Understanding the response of groundwater levels to meteorological and anthropogenic factors is a key step to propose water management alternatives. Meteorological and groundwater data were used to design a multi-step approach to assess the influential factors on the groundwater system in the City of Chihuahua, Mexico. The analysis of historical groundwater levels and climate showed a clear increase in meteorological drought, as well as a groundwater abstraction trend since 1986. Rainfall, groundwater recharge, and groundwater level displayed a significant decrease. Overall, the groundwater depth is continuously increasing with a strong correlation with groundwater abstraction. Despite having a significant trend, the changes in land-cover, groundwater recharge, and meteorological drought were not the main factors inducing the decreased level of water in the aquifer. The continuous abstraction of groundwater from 1986 to 2010 has led to a depletion of groundwater levels from 32 to 92 m. The findings of this study lay a foundation for future water resource management in the study area.

The Impact of the COVID-19 Pandemic on Medical Imaging Case Volumes in Aseer Region: A Retrospective Study

COVID-19 has had a significant impact on global health systems. The aim of this study was to evaluate how imaging volumes and imaging types in radiology departments have been affected by the COVID-19 pandemic across different locations. Methods: Imaging volumes in the Aseer region (in the south of Saudi Arabia) across main hospitals were reviewed retrospectively including all cases referred from different locations (outpatient, inpatient and emergency departments). Data for years 2019 and 2020 were compared. The mean monthly cases were compared using a t-test. Results: The total imaging volumes in 2019 were 205,805 compared to 159,107 in 2020 with a 22.7% overall reduction. A substantial decline was observed in both the April to June and the July to September periods of approximately 42.9% and 44.4%, respectively. With respect to location, between April and June, the greatest decline was observed in outpatient departments (76% decline), followed by emergency departments (25% decline), and the least impact was observed in inpatient departments, with only 6.8% decline over the same period. According to modality type, the greatest decreases were reported in nuclear medicine, ultrasound, MRI, and mammography, by 100%, 76%, 74%, and 66%, respectively. Our results show a statistically significant (p-value ≤ 0.05) decrease of cases in 2020 compared to 2019, except for mammography procedures. Conclusion: There has been a significant decline in radiology volumes due to COVID-19. The overall reduction in radiology volumes was dependent on the stage/period of lockdown, location, and imaging modality.

Vegetation Characteristics and Recent Successional Trends of Sand Dune Habitats at the Bulgarian Black Sea Coast

Coastal dunes are valuable and vulnerable habitats that require scientific exploration and understanding of their natural processes; therefore, the aims of this study were to determine the current vegetation characteristics of dune habitats along the Bulgarian Coast in terms of species richness and cover of typical psammophytes and different non-psammophytic plant groups, and to analyze how they respond to certain environmental drivers. Data were collected from 12 dune systems. The research was focused on embryonic, white and grey dunes. The field work was conducted throughout July and August 2017. The vegetation was sampled at 154 phytosociological plots (5 m × 5 m). To understand how the vegetation responds to different drivers, we tested the correlation of defined species group richness and cover in relation to (1) the soil pH and EC values, (2) the distance from inland to the sea and (3) the range of different categories of land cover in the surrounding area. In order to track temporal vegetation changes, we compared the cover of defined species groups between 2003 and 2017. We registered a total number of 269 vascular plants, 12 bryophytes and 5 lichens. The strongest presence in all dune types, both in species richness and cover, was the group of grass- and shrubland plants. Weeds and ruderal plants had significant coverage in grey dunes, while the richness and cover of forest and alien plants were negligible among the studied dune habitats. The comparison of data between 2003 and 2017 revealed a substantial decline in the cover of psammophytes. We observed a clear pattern regarding the share of species richness of psammophytes and non-psammophytes among different locations. We detected that grey dunes were the most affected by the penetration of non-psammophytes.

FINANCIAL AND INVESTMENT DETERMINANTS OF REGIONAL DEVELOPMENT IN THE FACE OF ECONOMIC UNCERTAINTY

The research aims to evaluate the development trends of Ukrainian regions in conditions of COVID-19 spread under the impact of financial and investment determinants. In the article, it is made the profound examination of the impact the restrictive and stimulating tools of public policy at national and regional levels have on the current condition of regional economic systems, in particular in the context of such components as price stability, investment attraction, business climate improvement, lending, capital investment, transparency of budget revenue-forming taxes administration, and stability of public finance. These sectors are most sensitive to public policy measures, particularly in conditions of social turbulence. The analysis of financial determinants of regional development in conditions of the corona crisis has contributed to outlining the following negative trends: substantial decline in investments in the economy of regions and a falling share of new investment projects are the most negative consequences that will essentially affect the paces of economic growth in the following periods; deteriorating business climate, falling volumes of loans provided to economic entities, and growing share of short-term loans have affected new investment decisions; failure to fulfill the planned rates of the local budgets’ main revenue-generating indicators (PIT, local taxes) has affected the volumes of revenues from local budgets, including the investment ones; decline in transfers to local budgets from the public one has affected the funding of regional development programs; the foreign capital outflow occurred not only because of the deteriorating business climate in the country but also the inclusive nature of the COVID-19 pandemics and psychological-emotional factors of impact on the investors’ behavior in conditions of uncertainty. The economic, fiscal, and social impacts of COVID-19 are territorially differentiated. Its various risks are much caused by economic and spatial features of regional development. At the same time, the panic caused by the COVID-19 spread leading to making a range of irrational decisions by financial-economic entities at various governance levels is an essential reason for the defined problems’ aggravation. The substantial decline in investments in the economy of regions and a falling share of new investment projects are the most negative consequences that will essentially affect the paces of economic growth in the following periods. Keywords: regional development, economic uncertainty, COVID-19, finance, investments, determinants. JEL Classification O18, H71 Formulas: 0; fig.: 2; tabl.: 3; bibl.: 15.