Alk-2-enylstannanes with 4-, 5- and 6-alkoxy- or -hydroxy-substituents are transmetallated stereoselectively with tin(iv) halides to generate allyltin trihalides which react with aldehydes to give (Z)-alk-3-enols with useful levels of 1,5-, 1,6- and 1,7-stereocontrol. Alk-2-enylstannanes with a stereogenic centre bearing a hydroxy or alkoxy group at the 4-, 5- or 6-position, react with overall (Z)-1,5-, 1,6- and 1,7-syn-stereoselectivity with respect to the hydroxy and alkoxy substituents. The analogous reactions of alkoxy- and -hydroxyalk-2-enylstannanes with a methyl bearing stereogenic centre at the 4- or 5-position react with overall (Z)-1,5- and 1,6-anti-stereoselectivity with respect to the hydroxy and methyl substituents.
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http://dx.doi.org/10.1039/c0ob01084g | DOI Listing |
Eur Radiol
January 2025
Department of Information Technology, Uppsala University, 75237, Uppsala, Sweden.
Objectives: The aim is to assess the feasibility and accuracy of a novel quantitative ultrasound (US) method based on global speed-of-sound (g-SoS) measurement using conventional US machines, for breast density assessment in comparison to mammographic ACR (m-ACR) categories.
Materials And Methods: In a prospective study, g-SoS was assessed in the upper-outer breast quadrant of 100 women, with 92 of them also having m-ACR assessed by two radiologists across the entire breast. For g-SoS, ultrasonic waves were transmitted from varying transducer locations and the image misalignments between these were then related analytically to breast SoS.
Trop Anim Health Prod
January 2025
Department of Animal Production, Faculty of Agriculture, Menoufia University, Shibin Al Kawm, Egypt.
This article aims to explore milking-ability criteria of Holstein dairy cattle under intensive production system in Egypt and investigate some managerial factors that influence them in dairy farms. The data obtained from five herds belong to a commercial intensive production system farm, Egypt. Data included 3509 records.
View Article and Find Full Text PDFAnn Emerg Med
January 2025
Department of Emergency Medicine, Kaiser Permanente San Diego Medical Center, San Diego, CA.
Study Objective: This study analyzes emergency medicine airway management trends and outcomes among community emergency departments.
Methods: A multicenter, retrospective chart review was conducted on 11,475 intubations from 15 different community emergency departments between January 1, 2015, and December 31, 2022. Data collected included patient's age, sex, rapid sequence intubation medications, use of cricoid pressure, method of intubation, number of attempts, admission diagnosis, and all-cause mortality rates.
JACC Cardiovasc Imaging
January 2025
Ciccarone Center for the Prevention of Cardiovascular Disease, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA. Electronic address:
Background: Implementation of semaglutide weight loss therapy has been challenging due to drug supply and cost, underscoring a need to identify those who derive the greatest absolute benefit.
Objectives: Allocation of semaglutide was modeled according to coronary artery calcium (CAC) among individuals without diabetes or established atherosclerotic cardiovascular disease (CVD).
Methods: In this analysis, 3,129 participants in the MESA (Multi-Ethnic Study of Atherosclerosis) without diabetes or clinical CVD met body mass index criteria for semaglutide and underwent CAC scoring on noncontrast cardiac computed tomography.
J Wound Care
January 2025
Nursing and Health Care, School of Health Sciences, South East Technological University, Waterford City, Ireland.
Objective: Wound management can be costly and challenging to the health services' scarce resources. Information regarding the number of wounds in a community care setting and their associated aetiology will provide nurses and nurse managers with an insight into the specific needs of these clients with wounds and highlight areas where care or services can be improved or further developed. This research aimed to establish the prevalence and aetiology of wounds, the current delivery of wound care, wound documentation and referral pathways in an Irish community care setting.
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