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1.
J Am Chem Soc ; 145(12): 6730-6740, 2023 Mar 29.
Article in English | MEDLINE | ID: mdl-36916242

ABSTRACT

The reactions of H2, CO2, and CO gas mixtures on the surface of Cu at 200 °C, relevant for industrial methanol synthesis, are investigated using a combination of ambient pressure X-ray photoelectron spectroscopy (AP-XPS) and atmospheric-pressure near edge X-ray absorption fine structure (AtmP-NEXAFS) spectroscopy bridging pressures from 0.1 mbar to 1 bar. We find that the order of gas dosing can critically affect the catalyst chemical state, with the Cu catalyst maintained in a metallic state when H2 is introduced prior to the addition of CO2. Only on increasing the CO2 partial pressure is CuO formation observed that coexists with metallic Cu. When only CO2 is present, the surface oxidizes to Cu2O and CuO, and the subsequent addition of H2 partially reduces the surface to Cu2O without recovering metallic Cu, consistent with a high kinetic barrier to H2 dissociation on Cu2O. The addition of CO to the gas mixture is found to play a key role in removing adsorbed oxygen that otherwise passivates the Cu surface, making metallic Cu surface sites available for CO2 activation and subsequent conversion to CH3OH. These findings are corroborated by mass spectrometry measurements, which show increased H2O formation when H2 is dosed before rather than after CO2. The importance of maintaining metallic Cu sites during the methanol synthesis reaction is thereby highlighted, with the inclusion of CO in the gas feed helping to achieve this even in the absence of ZnO as the catalyst support.

2.
J Plast Reconstr Aesthet Surg ; 73(12): 2111-2120, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32747182

ABSTRACT

BACKGROUND: Prominent ears are the most common congenital abnormality of the head and neck, occurring in 5% of the Caucasian population. Facial disfigurement can cause psychosocial distress, low self-esteem and varying levels of social isolation most notable in school-age children. Although prominent ear correction is the most frequently performed aesthetic operation in children and adolescents, to our knowledge, the relationship between prominent ears and psychological, social and educational issues has not been systematically assessed. PURPOSE OF STUDY: To investigate the psychological, social and educational impact of prominent ears and to examine how prominent ear correction affects health-related quality of life (HRQoL). METHODS: A systematic review was conducted using a protocol registered with PROSPERO and in line with the Preferred Reporting for Items for Systematic Reviews and Meta-Analyses statement. A comprehensive search of the literature was conducted using MEDLINE, EMBASE, PyscINFO, HMIC Health Management Information Consortium, Ovid Journals Database, NHS Wales Full-Text Journals and The Cochrane Database. The inclusion criteria stated that any study investigating the association between psychological, social or educational issues, or HRQoL and prominent ears or otoplasty should be incorporated. All studies were reviewed by two authors, with data extracted for the studies finally included. FINDINGS: Fourteen articles were finally included, with a total of 786 patients. Thirteen out of 14 papers analysed the post-operative effect of surgical correction of prominent ears. The most common motivating factor for surgery was bullying, with young males of school age being the worst affected. Prominent ear patients report higher levels of bullying and social problems, and lower levels of physical activity than patients with more severe facial disfigurements. Every study that assessed the psychosocial impact of surgery on prominent ears found a significant benefit to HRQoL. CONCLUSION AND RELEVANCE: Prominent ears pose severe psychological and social issues that should not be underestimated. Surgical correction has consistently been shown to significantly improve HRQoL.


Subject(s)
Ear, External/surgery , Educational Status , Otologic Surgical Procedures/psychology , Self Concept , Social Adjustment , Social Isolation , Adolescent , Bullying , Child , Ear, External/abnormalities , Humans
3.
Med Image Anal ; 38: 184-204, 2017 05.
Article in English | MEDLINE | ID: mdl-28411458

ABSTRACT

Traditional histology is the gold standard for tissue studies, but it is intrinsically reliant on two-dimensional (2D) images. Study of volumetric tissue samples such as whole hearts produces a stack of misaligned and distorted 2D images that need to be reconstructed to recover a congruent volume with the original sample's shape. In this paper, we develop a mathematical framework called Transformation Diffusion (TD) for stack alignment refinement as a solution to the heat diffusion equation. This general framework does not require contour segmentation, is independent of the registration method used, and is trivially parallelizable. After the first stack sweep, we also replace registration operations by operations in the space of transformations, several orders of magnitude faster and less memory-consuming. Implementing TD with operations in the space of transformations produces our Transformation Diffusion Reconstruction (TDR) algorithm, applicable to general transformations that are closed under inversion and composition. In particular, we provide formulas for translation and affine transformations. We also propose an Approximated TDR (ATDR) algorithm that extends the same principles to tensor-product B-spline transformations. Using TDR and ATDR, we reconstruct a full mouse heart at pixel size 0.92µm×0.92µm, cut 10µm thick, spaced 20µm (84G). Our algorithms employ only local information from transformations between neighboring slices, but the TD framework allows theoretical analysis of the refinement as applying a global Gaussian low-pass filter to the unknown stack misalignments. We also show that reconstruction without an external reference produces large shape artifacts in a cardiac specimen while still optimizing slice-to-slice alignment. To overcome this problem, we use a pre-cutting blockface imaging process previously developed by our group that takes advantage of Brewster's angle and a polarizer to capture the outline of only the topmost layer of wax in the block containing embedded tissue for histological sectioning.


Subject(s)
Algorithms , Diffusion , Imaging, Three-Dimensional/methods , Animals , Artifacts , Heart/diagnostic imaging , Mice
4.
Genome ; 47(3): 475-92, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15190365

ABSTRACT

Quantitative trait loci (QTLs) for resistance to Phytophthora infestans (late blight) were mapped in tomato. Reciprocal backcross populations derived from cultivated Lycopersicon esculentum x wild Lycopersicon hirsutum (BC-E, backcross to L. esculentum; BC-H, backcross to L. hirsutum) were phenotyped in three types of replicated disease assays (detached-leaflet, whole-plant, and field). Linkage maps were constructed for each BC population with RFLPs. Resistance QTLs were identified on all 12 tomato chromosomes using composite interval mapping. Six QTLs in BC-E (lb1a, lb2a, lb3, lb4, lb5b, and lb11b) and two QTLs in BC-H (lb5ab and lb6ab) were most consistently detected in replicated experiments or across assay methods. Lycopersicon hirsutum alleles conferred resistance at all QTLs except lb2a. Resistance QTLs coincided with QTLs for inoculum droplet dispersal on leaves, a trait in L. hirsutum that may contribute to resistance, and dispersal was mainly associated with leaf resistance. Some P. infestans resistance QTLs detected in tomato coincided with chromosomal locations of previously mapped R genes and QTLs for resistance to P. infestans in potato, suggesting functional conservation of resistance within the Solanaceae.


Subject(s)
Phytophthora/pathogenicity , Quantitative Trait Loci , Solanum lycopersicum/microbiology , Solanum tuberosum/microbiology , Polymorphism, Restriction Fragment Length
5.
Genetics ; 165(1): 331-42, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14504240

ABSTRACT

Determining parentage is a fundamental problem in biology and in applications such as identifying pedigrees. Difficulties inferring parentage derive from extensive inbreeding within the population, whether natural or planned; using an insufficient number of hypervariable loci; and from allele mismatches caused by mutation or by laboratory errors that generate false exclusions. Many studies of parentage have been limited to comparisons of small numbers of specific parent-progeny triplets. There have been few large-scale surveys of candidates in which there is no prior knowledge of parentage. We present an algorithm that determines the probability of parentage in circumstances where there is no prior knowledge of pedigree and that is robust in the face of missing data and mistyped data. The focus is parentage of an inbred line having uncertain ancestry. The algorithm is a variation of a previously published hybrid-focused algorithm. We describe the algorithm and demonstrate its performance in determining parentage of 43 inbred varieties of soybean that have been profiled using 236 SSR loci and from seven inbred varieties of maize that were profiled using 70 SSR loci. We include simulations of additional levels of missing and mistyped data to show the algorithm's utility and flexibility.


Subject(s)
Glycine max/genetics , Minisatellite Repeats , Zea mays/genetics , Data Interpretation, Statistical , Inbreeding , Phylogeny
6.
Genome ; 45(2): 282-95, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11962626

ABSTRACT

A molecular-marker linkage map has been constructed for perennial ryegrass (Lolium perenne L.) using a one-way pseudo-testcross population based on the mating of a multiple heterozygous individual with a doubled haploid genotype. RFLP, AFLP, isoenzyme, and EST data from four collaborating laboratories within the International Lolium Genome Initiative were combined to produce an integrated genetic map containing 240 loci covering 811 cM on seven linkage groups. The map contained 124 codominant markers, of which 109 were heterologous anchor RFLP probes from wheat, barley, oat, and rice, allowing comparative relationships between perennial ryegrass and other Poaceae species to be inferred. The genetic maps of perennial ryegrass and the Triticeae cereals are highly conserved in terms of synteny and colinearity. This observation was supported by the general agreement of the syntenic relationships between perennial ryegrass, oat, and rice and those between the Triticeae and these species. A lower level of synteny and colinearity was observed between perennial ryegrass and oat compared with the Triticeae, despite the closer taxonomic affinity between these species. It is proposed that the linkage groups of perennial ryegrass be numbered in accordance with these syntenic relationships, to correspond to the homoeologous groups of the Triticeae cereals.


Subject(s)
Chromosome Mapping , DNA, Plant/genetics , Genome, Plant , Lolium/genetics , Poaceae/genetics , Crosses, Genetic , DNA, Plant/isolation & purification , Expressed Sequence Tags , Genetic Linkage , Genetic Markers , Genotype , Haploidy , Heterozygote , Isoenzymes/genetics , Lolium/enzymology , Polymorphism, Restriction Fragment Length , Repetitive Sequences, Nucleic Acid , Species Specificity , Synteny
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