A triarylborane (2) bearing three o-carborane cages at peripheral positions on the aryl groups was prepared and its crystal structure was determined from X-ray diffraction study. Treatment of 2 with KF in the presence of 18-crown-6 led to the potassium salt, [2F](-). A UV-vis titration experiment carried out in THF/H(2)O (9/1 v/v) showed that 2 binds fluoride ions with a binding constant (K) of 4.8 × 10(4) M(-1), which is an order-of-magnitude greater than K for the mono-carborane substituted triarylborane. The enhanced fluoride ion affinity of 2 indicates an apparent additive effect of multiple carborane substitutions on the Lewis acidity enhancement of the triarylborane. The highly Lewis acidic nature of 2 was further utilized in evaluating the fluoride ion affinity of tris(pentafluorophenyl)borane (B(C(6)F(5))(3)). A fluoride exchange reaction between [2F](-) and B(C(6)F(5))(3) resulted in 15 times higher fluorophilicity for B(C(6)F(5))(3) than for 2. The lower Lewis acidity of 2 compared with B(C(6)F(5))(3) was confirmed from its greater cathodic reduction potential.
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Sci Rep
January 2025
Department of Geography, School of Environment, Education and Development, The University of Manchester, Arthur Lewis Building, Oxford Road, Manchester, M13 9PL, UK.
Urban woodland composition and configuration have strong associations with land surface temperatures (LST), but the evidence is contradictory due to different spatial scales, regional climate zones, woodland types and urban contexts. In this study, we analyse associations between urban woodland and LST within and between five cities in different Köppen climate zones. Our consistent methodology is framed around local climate zones and conducted at a fine spatial scale.
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December 2024
Department of Otolaryngology-Head and Neck Surgery, Harvard Medical School, Boston, MA 02115, USA.
Human papillomavirus (HPV)-associated head and neck squamous cell carcinoma (HPV-positive HNSCC) has distinct biological characteristics from HPV-negative HNSCC. Using an AI-based analytical platform on meta cohorts, we profiled expression patterns of viral transcripts and HPV viral genome integration, and classified the tumor microenvironment (TME). Unsupervised clustering analysis revealed five distinct and novel TME subtypes across patients (immune-enriched, highly immune and B-cell enriched, fibrotic, immune-desert, and immune-enriched luminal).
View Article and Find Full Text PDFFoods
January 2025
College of Agriculture, Science and Technology, Delaware State University, 1200 North DuPont Highway, Dover, DE 19901, USA.
Due to an increased demand for natural food additives, clove oil was assessed as a natural alternative to chemical disinfectants in produce washing. This study assessed the antimicrobial activity of 5 and 10% (/) clove oil-amended wash liquid (CO) using a zone of inhibition (ZIB) test and determined the time required to completely inactivate pathogenic bacteria using bacterial death curve analysis. A washing experiment was used to evaluate CO's ability to inhibit bacterial growth on inoculated RTE spinach and in the wash water.
View Article and Find Full Text PDFAnn Vasc Surg
January 2025
Department of Surgery, Division of Cardiothoracic Surgery, Lewis Katz School of Medicine at Temple University, Philadelphia, PA.
Objective: Medicare insures over 65 million Americans and is a primary driver of private insurance reimbursement rates. However, public data shows Medicare reimbursement for comparatively complex procedures such as aortic aneurysm repair is disproportionate. Medicare reimbursement rates are multifactorial and highly localized, yet little is known about nationwide trends.
View Article and Find Full Text PDFDokl Biochem Biophys
January 2025
State Research Center-Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, 123098, Moscow, Russia.
Background: The effects of ionizing radiation (IR) involve a highly orchestrated series of events in cells, including DNA damage and repair, cell death, and changes in the level of proliferation associated with the stage of the cell cycle. A large number of existing studies in literature have examined the activity of genes and their regulators in mammalian cells in response to high doses of ionizing radiation. Although there are many studies, the research in effect of low doses of ionizing radiation remains limited.
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