Gas-phase reactions in the interstellar medium (ISM) are a source of molecules in this environment. The knowledge of the rate coefficient for neutral-neutral reactions as a function of temperature, k(T), is essential to improve astrochemical models. In this work, we have experimentally measured k(T) for the reaction between the OH radical and acetaldehyde, both present in many sources of the ISM. Laser techniques coupled to a CRESU system were used to perform the kinetic measurements. The obtained modified Arrhenius equation is k(T = 11.7-177.5 K) = (1.2 ± 0.2) × 10-11 (T/300 K)-(1.8±0.1) exp-{(28.7 ± 2.5)/T} cm3 molecule-1 s-1. The k(T) value of the title reaction has been measured for the first time below 60 K. No pressure dependence of k(T) was observed at ca. 21, 50, 64 and 106 K. Finally, a pure gas-phase model indicates that the title reaction could become the main CH3CO formation pathway in dark molecular clouds, assuming that CH3CO is the main reaction product at 10 K.
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http://dx.doi.org/10.1039/d0cp03203d | DOI Listing |
Contact Dermatitis
January 2025
Clinic of Dermatology, University Hospital and Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
Background: Since its inception in 1980, the MOHL index (% patients who are male, have occupational, hand, or leg dermatitis, respectively) and its later evolutions until the presently used MOAHLFA(P) index (adding % patients with atopic dermatitis, face dermatitis, age 40+ years and positive reaction(s) to ≥ 1 baseline series allergen) have been intended to convey important demographic and clinical information on the patients patch tested in a certain area and time, aiding the interpretation of the observed spectrum of sensitisation.
Objectives: To examine the current usage of the MOAHLFA(P) index and suggest consolidated definitions for its single items.
Methods: A title/abstract search in Medline identified publications mentioning the evolving acronyms.
Foods
December 2024
Research Group in Community Nutrition and Oxidative Stress, University of the Balearic Islands-IUNICS, 07122 Palma de Mallorca, Spain.
Food neophobia and pickiness are the resistance or refusal to eat and/or avoid trying new foods due to a strong reaction of fear towards the food or an entire group of foods. This systematic review aims to assess evidence on the risk factors and effects of food neophobia and picky eating in children and adolescents, giving elements to avoid the lack of some foods that can cause nutritional deficiencies, leading to future pathologies when they are adults. A systematic literature search was performed in Medlars Online International Literature (MEDLINE) via Pubmed and EBSCOhost, LILACS and IBECS via Virtual Health Library (VHL), Scopus, and Google Scholar.
View Article and Find Full Text PDFCureus
December 2024
Pathology, BLDE (Deemed to be University) Shri B.M. Patil Medical College, Hospital, and Research Centre, Vijayapura, IND.
Introduction Occupational health hazards are a significant concern for pathologists due to their unique work environment. These professionals face risks from prolonged microscope use, exposure to chemicals such as formalin, and handling sharp instruments, leading to issues such as musculoskeletal disorders and needlestick injuries. Addressing these hazards is crucial for their well-being and the overall efficiency of medical diagnostics.
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
January 2025
Institut für Anorganische Chemie, Universität Kiel, Max-Eyth.-Str. 2, 24118 Kiel, Germany.
Reaction of Co(NCS) with 4-methyl-pyridine in water leads to the formation of single crystals of the title compound, [Co(NCS)(CHN)] . The asymmetric unit consists of two crystallographically independent thio-cyanate anions and two crystallographically independent 4-methyl-pyridine coligands in general positions, as well as of two different Co cations, of which one is located on a twofold rotational axis, whereas the second occupies a center of inversion. The methyl H atoms in both 4-methyl-pyridine ligands are disordered and were refined using a split model.
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
January 2025
Institut für Anorganische Chemie, Universität Kiel, Max-Eyth.-Str. 2, 24118 Kiel, Germany.
The title compound, [CdBr(CHN)] , was prepared by the reaction of cadmium bromide with 2,5-di-methyl-pyrazine in water. Its asymmetric unit consists of one Cd cation and one 2,5-di-methyl-pyrazine ligand that are located on a crystallographic mirror plane as well as one bromide anion that occupies a general position. The Cd cations are sixfold coordinated by four bromide anions and two 2,5-di-methyl-pyrazine ligands within slightly distorted -CdBrN octa-hedra.
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