Chemical properties of ethylene oxide (EO) and propylene oxide (PO) block copolymers are strongly dependent on their sequence. Useful information about copolymer sequence can be obtained by tandem mass spectrometry (MS/MS). In this work, collision-induced dissociation (CID) of ammonium adducts of various linear triblock and glycerol derivative diblock copolyethers produced by electrospray ionization was studied under low-energy conditions. At first, homopolymers MS/MS spectra enabled us to identify the nature of the product ions and to suggest decomposition pathways. Then, it was shown that copolyethers with the same composition in each repeat unit but with inversed block sequences (i.e., PEO-b-PPO-b-PEO vs PPO-b-PEO-b-PPO and gPEO-b-PPO vs gPPO-b-PEO) can be easily distinguished with characteristic fragment ions. In the case of linear copolymers, CID spectra gave pertinent information about block lengths.
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http://dx.doi.org/10.1021/ac051308h | DOI Listing |
PLoS One
January 2025
College of Physics and Electronic Engineering, Hainan Normal University, HaiKou, China.
We have successfully prepared a significant number of nanowires from non-toxic silicon sources. Compared to the SiO silicon source used in most other articles, our preparation method is much safer. It provides a simple and harmless new preparation method for the preparation of silicon nanowires.
View Article and Find Full Text PDFJ Evol Biol
January 2025
Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals de la Universitat de Barcelona (BEECA), Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona.
Differences in habitat use impose ecological constraints which in turn lead to functional and morphological differences through adaptation. In fact, a convergent evolutionary pattern is evident when species exhibit similar responses to similar environments. In this study we examine how habitat use influences the evolution of body shape in lizards from the family Lacertidae.
View Article and Find Full Text PDFPLoS One
January 2025
Department of Cardiovascular Sciences, Anaesthesia, Critical Care and Pain Management, University of Leicester, Leicester, United Kingdom.
Sustained pathologic myocardial hypertrophy can result in heart failure(HF); a significant health issue affecting a large section of the population worldwide. In HF there is a marked elevation in circulating levels of the peptide urotensin II(UII) but it is unclear whether this is a result of hypertrophy or whether the high levels contribute to the development of hypertrophy. The aim of this study is to investigate a role of UII and its receptor UT in the development of cardiac hypertrophy and the signalling molecules involved.
View Article and Find Full Text PDFJ Bone Joint Surg Am
November 2024
Department of Neurosurgery, Bokwang Hospital, Daegu, Republic of Korea.
Background: Oblique lumbar interbody fusion (OLIF) results in less tissue damage than in other surgeries, but immediate postoperative pain occurs. Notably, facet joint widening occurs in the vertebral body after OLIF. We hypothesized that the application of a facet joint block to the area of widening would relieve facet joint pain.
View Article and Find Full Text PDFPediatr Surg Int
January 2025
Department of Paediatric Surgery, Children's Health Ireland at Crumlin, Dublin, Ireland.
Background: Appendicectomy is a common procedure in children. Regional anaesthesia helps reduce requirements for opioids and hospital stay and enhances recovery. Laparoscopic-assisted Transversus Abdominus Plane block (L-TAP) was shown to be efficient and potentially superior to port site infiltration (PSI); however, this was not previously studied in paediatric appendicitis.
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