Employing dimensionality-reduced time-independent quantum scattering theory and summation over all possible total angular momentum states, initial-state selected reaction cross sections for the exothermic gas-phase bimolecular nucleophilic substitution (SN2) reaction Cl(-) + CH3Br → ClCH3 + Br(-) have been calculated. The carbon-halogen bonds and the rotation of the methyl halides are taken into account. In agreement with previous calculations for J = 0, initial rotational motion of CH3Br decreases the reaction probability and consequently the cross sections. The experimentally obtained thermal rate constant for 300 K is reproduced within the experimental error. For lower temperatures, it is calculated to be below the experimental values but shows the same strong increase for T → 0.
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Ann Surg Oncol
January 2025
Department of Hepatobiliary and Digestive Surgery, Pontchaillou University Hospital, Rennes, France.
Background: Hepatocellular carcinoma (HCC) associated with major vasculature tumor extension is considered an advanced stage of disease to which palliative radiotherapy or chemotherapy is proposed. Surgical resection associated with chemotherapy or chemoembolization could be an opportunity to improve overall survival and recurrence-free survival in selected cases in a high-volume hepatobiliary center. Moreover, it has been 25 years since Couinaud described the entity of a posterior liver located behind an axial plane crossing the portal bifurcation.
View Article and Find Full Text PDFSci Data
January 2025
Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
As the occurrence of human diseases and conditions increase, questions continue to arise about their linkages to chemical exposure, especially for per-and polyfluoroalkyl substances (PFAS). Currently, many chemicals of concern have limited experimental information available for their use in analytical assessments. Here, we aim to increase this knowledge by providing the scientific community with multidimensional characteristics for 175 PFAS and their resulting 281 ion types.
View Article and Find Full Text PDFObjective: A study conducted in Rio de Janeiro aimed to identify the factors contributing to the high rate of cesarean deliveries in the city, which is over three times higher than the World Health Organization recommended. However, the city has a role in strategies and policies to empower primary care and to organize delivery care.
Methods: We conducted a cross-sectional study using the Live Birth Information System from 2012 to 2021.
Food Chem
January 2025
College of Food Science and Technology, Hebei Agricultural University, Baoding 071001, China. Electronic address:
The shelf-life of grapes is reduced due to infection by various pathogens and mechanical damage, which consequently limits their availability on the market and results huge economic losses. Active packaging films are expected to overcome this problem. In this study, packaging films (CMC-Gly-PMA) were developed using wheat straw-based carboxymethyl cellulose (2 %), glycerol (30 % w/w of CMC) and polymalate (0.
View Article and Find Full Text PDFPoult Sci
January 2025
Department of Microbiology, Faculty of Basic Sciences, East Tehran Branch, Islamic Azad University, Tehran, Iran.
A major health and financial burden in the chicken sector is salmonella infection. It is difficult to create an oral vaccination that can provide strong intestinal mucosal immunity in birds, particularly cross-protection against several Salmonella serotypes. As a result, the poultry industry needs a powerful oral vaccination platform that uses live bacterial vectors to prevent various Salmonella serotypes.
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