The Relationship between Level of Vitamin C in Follicular Fluid and ‎Maturation of Oocytes and Embryo Quality in Patients Undergoing In-vitro ‎Fertilization

BACKGROUND AND OBJECTIVE: Oxidative stress and its adverse effects in vitro or on the body can reduce the number of reproductive cells and embryo quality. Given the fact that vitamin C is a natural antioxidant with a protective role, in this study we aimed to evaluate the relationship between the level of vitamin C in follicular fluid (FF) and maturation of oocytes and embryo quality of patients undergoing in vitro fertilization (IVF). METHODS: This cross-sectional study was performed on the eggs and embryos of 50 patients admitted to IVF unit of Al Zahra Hospital, Rasht, Iran. Patients underwent the same mediations used to induce ovulation, and then they were injected 10000 units of human chorionic gonadotropin. Finally, they underwent 36 hours of follicle suction. Vitamin C level in FF was measured by biochemical methods. Maturation of oocytes and embryo quality were examined with inverted light microscope. FINDINGS: After examining 583 eggs and 275 embryos the following results were obtained: the percentage of metaphase II oocytes in vitamin C level of less than one was 81.3% (412), but when compared to vitamin C level of one or more, it was 71.1% (54), which were significantly different (p=0.038). In the sub-classification, vitamin C level (0.5-1 mg/dl), MII oocyte frequency and the two pronuclei embryos were higher but the difference was not statistically significant. CONCLUSION: The results showed that the quality of oocyte maturation and embryos in lower levels of vitamin C levels had improved, as compared to higher levels

Hyperspectral imaging in the spatial frequency domain with a supercontinuum source.

We introduce a method for quantitative hyperspectral optical imaging in the spatial frequency domain (hs-SFDI) to image tissue absorption (μa) and reduced scattering (μs') parameters over a broad spectral range. The hs-SFDI utilizes principles of spatial scanning of the spectrally dispersed output of a supercontinuum laser that is sinusoidally projected onto the tissue using a digital micromirror device. A scientific complementary metal-oxide-semiconductor camera is used for capturing images that are demodulated and analyzed using SFDI computational models. The hs-SFDI performance is validated using tissue-simulating phantoms over a range of μa and μs' values. Quantitative hs-SFDI images are obtained from an ex-vivo beef sample to spatially resolve concentrations of oxy-, deoxy-, and met-hemoglobin, as well as water and fat fractions. Our results demonstrate that the hs-SFDI can quantitatively image tissue optical properties with 1000 spectral bins in the 580- to 950-nm range over a wide, scalable field of view. With an average accuracy of 6.7% and 12.3% in μa and μs', respectively, compared to conventional methods, hs-SFDI offers a promising approach for quantitative hyperspectral tissue optical imaging.Funding agencies:  National Institute of Health (NIH) NIBIB Biomedical Technology Research Center LAMMP [P41EB015890]; NIH [R21EB020953]; Military Medical Photonics Program: AFOSR [FA9550-17-1-0193]; Arnold and Mabel Beckman Foundation</p

Quantification and Analysis of Micro-Level Activities Data from Children Aged 1–12 Years Old for Use in the Assessments of Exposure to Recycled Tire on Turf and Playgrounds

Background: There are growing health concerns about exposure to toxicants released from recycled tire rubber, which is commonly used in synthetic turf and playground mats. To better estimate children’s exposure and risk from recycled tire rubber used in synthetic turf and playground mats, there is a need to collect detailed accurate information on mouthing activity and dermal contact behaviors. The objective of this study was to quantify and analyze micro-level activity time series (MLATS) data from children aged 1–12 years old while playing (non-sport-related games) at turf-like locations and playgrounds. Another objective was to estimate the incidental ingestion rate of rubber crumb among children. Methods: Hand and mouth contact frequency, hourly duration, and median contact duration with different objects were calculated for children playing on turf (i.e., parks, lawns, and gardens) (n = 56) and for children playing on playground structures (n = 24). Statistically significant differences between males and females as well as children’s age groups were evaluated. The daily incidental ingestion rate of rubber crumb was calculated. Results: For children playing on turf, there were significant differences between younger (1–6 y) and older (7–12 y) children for the mouthing median duration with non-dietary objects and all objects. For children playing on playground structures, we found significant mouthing frequency differences between younger (1–6 y) and older children (7–12 y) with all objects, and for mouthing median duration with non-dietary objects. There were no significant differences between males and females playing on artificial turf-like surfaces or playground mats. Our estimated mean incidental ingestion rate was 0.08, 0.07, and 0.08 g rubber crumb/day for children <2, 2–6, and 6–11 years old, respectively. Discussion: our results suggest that age and contact duration should be considered in risk assessment models to evaluate mouthing activities when children are playing on artificial turf surfaces or playground mats. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Misleading Disclosure of Pro Forma Earnings: An Empirical Examination

The Sarbanes–Oxley (SOX) Act was passed in 2002 in response to various instances of corporate malfeasance. The Act, designed to protect investors, led to wide-ranging regulation over various actions of managers, auditors and investment analysts. Part of SOX, and the focus of this study, targeted the disclosure by firms of “pro formaâ€\x9D earnings, an alternate (from GAAP earnings), flexible and unaudited measure of firm performance. Specifically, SOX directed the Securities and Exchange Commission (SEC) to craft regulation which would reduce – and preferably eliminate – any pro forma earnings disclosure which might be “misleadingâ€\x9D. Examining earnings press releases over a 3-year period, this study addresses three questions. Were firms disclosing pro forma in a potentially misleading manner, what was the nature of this potentially misleading disclosure, and did SOX affect the disclosure practices? We find the following. In 2001 (prior to SOX), 53 firms – over 10% of all U.S. S&P 500 firms – were disclosing pro forma earnings in a potentially misleading manner. This was being done most commonly by using traditional GAAP terminology (e.g., “net incomeâ€\x9D) in the press release headline to describe what was later in the press release revealed to be a pro forma amount (i.e., “net income excluding special itemsâ€\x9D). By 2003 (subsequent to the SEC regulation), potentially misleading disclosure practices were seen in less than 1% of the earnings press releases of S&P 500 firms. This significant reduction suggests that managers, prior to the regulation, were either careless in their pro forma reporting practice, or were intentionally – and unethically – attempting to mislead investors. Either way, we conclude that the SEC regulation was both necessary and effective. Copyright Springer Science+Business Media, Inc. 2006pro forma earnings, disclosure management, misleading, regulation,

Incentive Effects, Monitoring Mechanisms and the Market for Corporate Control: An Analysis of the Factors Affecting Public to Private Transactions in the UK

This paper investigates the factors that influence the decision to change the status of a publicly quoted company to that of a private company. We find that firms that go private are more likely to have higher CEO ownership and higher institutional ownership. In relation to their board structures, firms going private tend to have more duality but there is no statistical difference in the proportion of non-executive directors. They do not show signs of having excess free cash flows but there is some evidence of lower growth opportunities. We do not find that firms going private experience a greater threat of hostile acquisition. The results are therefore consistent with incentive and monitoring explanations of going private. Calculation of the probability of going private shows that incentive effects are stronger than the monitoring effects. Copyright Blackwell Publishers Ltd, 2005.