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1.
Circulation ; 148(11): 862-871, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37555345

RESUMO

BACKGROUND: Ventricular arrhythmia is an important cause of mortality in patients with ischemic left ventricular dysfunction. Revascularization with coronary artery bypass graft or percutaneous coronary intervention is often recommended for these patients before implantation of a cardiac defibrillator because it is assumed that this may reduce the incidence of fatal and potentially fatal ventricular arrhythmias, although this premise has not been evaluated in a randomized trial to date. METHODS: Patients with severe left ventricular dysfunction, extensive coronary disease, and viable myocardium were randomly assigned to receive either percutaneous coronary intervention (PCI) plus optimal medical and device therapy (OMT) or OMT alone. The composite primary outcome was all-cause death or aborted sudden death (defined as an appropriate implantable cardioverter defibrillator therapy or a resuscitated cardiac arrest) at a minimum of 24 months, analyzed as time to first event on an intention-to-treat basis. Secondary outcomes included cardiovascular death or aborted sudden death, appropriate implantable cardioverter defibrillator (ICD) therapy or sustained ventricular arrhythmia, and number of appropriate ICD therapies. RESULTS: Between August 28, 2013, and March 19, 2020, 700 patients were enrolled across 40 centers in the United Kingdom. A total of 347 patients were assigned to the PCI+OMT group and 353 to the OMT alone group. The mean age of participants was 69 years; 88% were male; 56% had hypertension; 41% had diabetes; and 53% had a clinical history of myocardial infarction. The median left ventricular ejection fraction was 28%; 53.1% had an implantable defibrillator inserted before randomization or during follow-up. All-cause death or aborted sudden death occurred in 144 patients (41.6%) in the PCI group and 142 patients (40.2%) in the OMT group (hazard ratio, 1.03 [95% CI, 0.82-1.30]; P=0.80). There was no between-group difference in the occurrence of any of the secondary outcomes. CONCLUSIONS: PCI was not associated with a reduction in all-cause mortality or aborted sudden death. In patients with ischemic cardiomyopathy, PCI is not beneficial solely for the purpose of reducing potentially fatal ventricular arrhythmias. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT01920048.


Assuntos
Desfibriladores Implantáveis , Disfunção Ventricular Esquerda , Humanos , Masculino , Idoso , Feminino , Volume Sistólico , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Função Ventricular Esquerda , Arritmias Cardíacas/etiologia , Disfunção Ventricular Esquerda/etiologia , Desfibriladores Implantáveis/efeitos adversos , Resultado do Tratamento
2.
Opt Express ; 30(15): 27967-27982, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-36236954

RESUMO

Recent advances in structured illumination are enabling a wide range of applications from imaging to metrology, which can benefit from advanced beam characterization techniques. Solving uniquely for the spatial distribution of polarization in a beam typically involves the use of two or more polarization optics, such as a polarizer and a waveplate, which is prohibitive for some wavelengths outside of the visible spectrum. We demonstrate a technique that circumvents the use of a waveplate by exploiting extended Gerchberg-Saxton phase retrieval to extract the phase. The technique enables high-resolution, wavefront-sensing, full-field polarimetry capable of solving for both simple and exotic polarization states, and moreover, is extensible to shorter wavelength light.

3.
Opt Express ; 30(17): 30331-30346, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36242139

RESUMO

We demonstrate temporally multiplexed multibeam ptychography implemented for the first time in the EUV, by using a high harmonic based light source. This allows for simultaneous imaging of different sample areas, or of the same area at different times or incidence angles. Furthermore, we show that this technique is compatible with wavelength multiplexing for multibeam spectroscopic imaging, taking full advantage of the temporal and spectral characteristics of high harmonic light sources. This technique enables increased data throughput using a simple experimental implementation and with high photon efficiency.

4.
Opt Express ; 29(3): 3342-3358, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33770934

RESUMO

Defect inspection on lithographic substrates, masks, reticles, and wafers is an important quality assurance process in semiconductor manufacturing. Coherent Fourier scatterometry (CFS) using laser beams with a Gaussian spatial profile is the standard workhorse routinely used as an in-line inspection tool to achieve high throughput. As the semiconductor industry advances toward shrinking critical dimensions in high volume manufacturing using extreme ultraviolet lithography, new techniques that enable high-sensitivity, high-throughput, and in-line inspection are critically needed. Here we introduce a set of novel defect inspection techniques based on bright-field CFS using coherent beams that carry orbital angular momentum (OAM). One of these techniques, the differential OAM CFS, is particularly unique because it does not rely on referencing to a pre-established database in the case of regularly patterned structures with reflection symmetry. The differential OAM CFS exploits OAM beams with opposite wavefront or phase helicity to provide contrast in the presence of detects. We numerically investigated the performance of these techniques on both amplitude and phase defects and demonstrated their superior advantages-up to an order of magnitude higher in signal-to-noise ratio-over the conventional Gaussian beam CFS. These new techniques will enable increased sensitivity and robustness for in-line nanoscale defect inspection and the concept could also benefit x-ray scattering and scatterometry in general.

5.
Nanotechnology ; 31(24): 245304, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32101799

RESUMO

We theoretically study particle-substrate interactions under laser irradiation. Van der Waals, electrostatic double layer and a laser induced dipole in the nanoparticle and an image dipole in the substrate were considered to be the major components of the total interaction potential. It was shown that laser-induced attractive potential energy between the particle and substrate reduces the potential barrier which increases the probability for metal nanoparticles to be deposited onto the substrate.

6.
Aging Ment Health ; 22(7): 881-888, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29068703

RESUMO

OBJECTIVES: The study sought to explore the lived experiences of people with dementia who participate in community-based gardening programmes. METHODS: A collaborative gardening project was conducted over six weeks at a day centre for people with dementia. Six participants were recruited from the centre's attendees. Each session was co-designed by participants. Semi-structured group interviews were conducted each week, and researcher observations were documented. Semi-structured interviews were also conducted with the centre's staff to explore their views and to contextualise gardening participants' experiences. Data were analysed inductively using thematic analysis. This paper focuses upon three of the study's emergent themes: identity, agency, and community. RESULTS: The findings revealed that for people with dementia, gardening is not merely a matter of enjoying time outdoors; it is a forum for the articulation of identity and selfhood and expression of agency, and can facilitate the development of new social bonds based upon shared interests, rather than a shared diagnosis. CONCLUSION: Gardening-based interventions can offer more than simply facilitating outdoor engagement and promoting social interaction. When conditions are right, gardening can be an effective vehicle for the promotion of social citizenship and expression of selfhood and agency in dementia.


Assuntos
Demência/psicologia , Jardinagem , Relações Interpessoais , Idoso , Demência/diagnóstico , Feminino , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde
7.
Crit Care Med ; 44(8): e614-24, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26950003

RESUMO

OBJECTIVES: Molecular mechanisms linking autonomic dysfunction with poorer clinical outcomes in critical illness remain unclear. We hypothesized that baroreflex dysfunction alone is sufficient to cause cardiac impairment through neurohormonal activation of (nicotinamide adenine dinucleotide phosphate oxidase dependent) oxidative stress resulting in increased expression of G-protein-coupled receptor kinase 2, a key negative regulator of cardiac function. DESIGN: Laboratory/clinical investigations. SETTING: University laboratory/medical centers. SUBJECTS: Adult rats; wild-type/nicotinamide adenine dinucleotide phosphate oxidase subunit-2-deficient mice; elective surgical patients. INTERVENTIONS: Cardiac performance was assessed by transthoracic echocardiography following experimental baroreflex dysfunction (sino-aortic denervation) in rats and mice. Immunoblots assessed G-protein-coupled receptor recycling proteins expression in rodent cardiomyocytes and patient mononuclear leukocytes. In surgical patients, heart rate recovery after cardiopulmonary exercise testing, time/frequency measures of parasympathetic variables were related to the presence/absence of baroreflex dysfunction (defined by spontaneous baroreflex sensitivity of <6 ms mm Hg). The associations of baroreflex dysfunction with intraoperative cardiac function and outcomes were assessed. MEASUREMENTS AND MAIN RESULTS: Experimental baroreflex dysfunction in rats and mice resulted in impaired cardiac contractility and upregulation of G-protein-coupled receptor kinase 2 expression. In mice, genetic deficiency of gp91 nicotinamide adenine dinucleotide phosphate oxidase subunit-2 prevented upregulation of G-protein-coupled receptor kinase 2 expression in conditions of baroreflex dysfunction and preserved cardiac function. Baroreflex dysfunction was present in 81 of 249 patients (32.5%) and was characterized by lower parasympathetic tone and increased G-protein-coupled receptor kinase 2 expression in mononuclear leukocytes. Baroreflex dysfunction in patients was also associated with impaired intraoperative cardiac contractility. Critical illness and mortality were more frequent in surgical patients with baroreflex dysfunction (relative risk, 1.66 [95% CI, 1.16-2.39]; p = 0.006). CONCLUSIONS: Reduced baroreflex sensitivity is associated with nicotinamide adenine dinucleotide phosphate oxidase subunit-2-mediated upregulation of G-protein-coupled receptor kinase 2 expression in cardiomyocytes and impaired cardiac contractility. Autonomic dysfunction predisposes patients to the development of critical illness and increases mortality.


Assuntos
Barorreflexo/fisiologia , Estado Terminal , Quinase 2 de Receptor Acoplado a Proteína G/metabolismo , Coração/fisiopatologia , NADPH Oxidases/metabolismo , Animais , Pressão Sanguínea/fisiologia , Ecocardiografia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Leucócitos Mononucleares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Complicações Pós-Operatórias/epidemiologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Procedimentos Cirúrgicos Operatórios/métodos , Regulação para Cima
8.
Arterioscler Thromb Vasc Biol ; 34(9): 1990-2000, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24990232

RESUMO

OBJECTIVE: Our recent studies have highlighted membrane type-1 matrix metalloproteinase (MMP)-14 as a selective marker for an invasive subset of macrophages potentially related to atherosclerotic plaque progression. Moreover, colony stimulating factors (CSF) may exert divergent effects on macrophage MMP expression, possibly through microRNAs. We, therefore, aim to identify and test the pathophysiological role of microRNAs, which modulate macrophage MMP-14 expression in atherosclerotic plaque progression. APPROACH AND RESULTS: Compared with macrophage CSF-differentiated macrophages, granulocyte/macrophage CSF-matured macrophages exhibited reduced MMP-14 mRNA levels but increased protein expression and activity, which resulted in heightened macrophage invasion. MicroRNA-24, identified to target MMP-14, was accordingly increased in macrophage CSF compared with granulocyte/macrophage CSF macrophages. Silencing microRNA-24 in macrophage CSF macrophages significantly increased MMP-14 expression and enhanced their invasive capacity, mimicking granulocyte/macrophage CSF macrophages, and suggesting that granulocyte/macrophage CSF modulates MMP-14 protein expression and subsequent macrophage invasion in a microRNA-24-dependent manner. In human coronary atherosclerotic plaques, increased MMP-14 protein expression in foam cell macrophages was associated with lesions exhibiting histological characteristics associated with an unstable phenotype. Furthermore, microRNA-24 expression in these atherosclerotic plaques was inversely related to MMP-14 protein expression. Moreover, stable plaques contained higher microRNA-24 levels than unstable plaques, and microRNA-24 colocalized with foam cell macrophages that exhibited low MMP-14 protein expression. Finally, in atherosclerotic mice (apolipoprotein E-deficient), microRNA-24 inhibition increased plaque size and macrophage MMP-14 expression. CONCLUSIONS: Taken together, our data demonstrates that downregulation of microRNA-24 promotes an invasive macrophage subset and plays a novel regulatory role in MMP-14 proteolytic activity and, therefore, plaque stability, highlighting its therapeutic potential.


Assuntos
Aterosclerose/metabolismo , Macrófagos/fisiologia , MicroRNAs/fisiologia , Animais , Apolipoproteínas E/deficiência , Aterosclerose/genética , Aterosclerose/terapia , Tronco Braquiocefálico , Células Cultivadas , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/patologia , Progressão da Doença , Regulação para Baixo , Feminino , Inativação Gênica , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Células HeLa , Humanos , Fator Estimulador de Colônias de Macrófagos/farmacologia , Macrófagos/efeitos dos fármacos , Masculino , Metaloproteinase 14 da Matriz/biossíntese , Metaloproteinase 14 da Matriz/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , RNA Interferente Pequeno/farmacologia , Proteínas Recombinantes/farmacologia
9.
Can Vet J ; 56(8): 850-4, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26246632

RESUMO

The objective was to identify a fat-to-protein ratio (FPR) cut-off to diagnose subclinical ketosis (SCK) and to evaluate the effect of propylene glycol (PPG) treatment of cows with high FPR. The optimized cut-off was > 1.42; sensitivity (Se) = 92%; specificity (Sp) = 65%. A cut-off > 1.5 was selected for the PPG trial for balanced Se-Sp. Fat-to-protein ratio cut-offs > 1.25, 1.35, 1.50, 1.60, and 1.70 resulted in Se-Sp of 100% to 49%, 96% to 59%, 75% to 78%, 33% to 90%, and 8% to 96%, respectively. The proportions of cows with FPR > 1.25, 1.35, 1.42, 1.50, 1.60, and 1.70 were 60%, 50%, 44%, 30%, 14%, and 6%, respectively. Incidences of clinical ketosis and milk yield were similar between cows that received 400 mL of PPG (n = 34) and control cows (n = 38). Prevalence of SCK at enrollment was 29.2%; therefore, FPR > 1.5 is not indicated for treatment. Lower cut-offs should be used for screening.


Utilité du ratio de matière grasse et de protéine sur la ligne de traite pour diagnostiquer une cétose subclinique et assigner le traitement au propylèneglycol chez les vaches laitières en lactation. L'objectif consistait à identifier un seuil du ratio de matière grasse et de protéine (RMGP) pour diagnostiquer une cétose subclinique et évaluer l'effet du traitement au propylèneglycol (PPG) chez les vaches présentant un RMGP élevé. Le seuil optimisé était de > 1,42; la sensibilité (Se) = 92 %; la spécificité (Sp) = 65 %. Un seuil de > 1,5 a été choisi pour l'essai au PPG pour des Se-Sp équilibrées. Des seuils de ratios de matière grasse et protéine de > 1,25, 1,35, 1,50, 1,60 et 1,70 ont produit des Se-Sp de 100 % et 49 %, de 96 % et 59 %, 75 % et 78 %, de 33 % et 90 % et de 8 % et 96 %, respectivement. Les proportions des vaches avec un RMGP de > 1,25, 1,35, 1,42, 1,50, 1,60 et 1,70 étaient de 60 %, 50 %, 44 %, 30 %, 14 % et 6 %, respectivement. L'incidence de cétose clinique et la production de lait étaient semblables entre les vaches qui avaient reçu 400 mL de PPG (n = 34) et les vaches témoins (n = 38). La prévalence de cétose subclinique au recrutement était de 29,2 %; par conséquent, un RMGP de > 1,5 n'est pas indiqué pour le traitement. Des seuils inférieurs devraient être utilisés pour le dépistage.(Traduit par Isabelle Vallières).


Assuntos
Doenças dos Bovinos/diagnóstico , Gorduras/química , Cetose/veterinária , Proteínas do Leite/química , Leite/química , Propilenoglicol/uso terapêutico , Animais , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Feminino , Cetose/tratamento farmacológico , Lactação/fisiologia , Sensibilidade e Especificidade
11.
Mediators Inflamm ; 2014: 276457, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25301980

RESUMO

Matrix metalloproteinase-14 (MMP-14) promotes vulnerable plaque morphology in mice, whereas tissue inhibitor of metalloproteinases-3 (TIMP-3) overexpression is protective. MMP-14(hi) TIMP-3(lo) rabbit foam cells are more invasive and more prone to apoptosis than MMP-14(lo) TIMP-3(hi) cells. We investigated the implications of these findings for human atherosclerosis. In vitro generated macrophages and foam-cell macrophages, together with atherosclerotic plaques characterised as unstable or stable, were examined for expression of MMP-14, TIMP-3, and inflammatory markers. Proinflammatory stimuli increased MMP-14 and decreased TIMP-3 mRNA and protein expression in human macrophages. However, conversion to foam-cells with oxidized LDL increased MMP-14 and decreased TIMP-3 protein, independently of inflammatory mediators and partly through posttranscriptional mechanisms. Within atherosclerotic plaques, MMP-14 was prominent in foam-cells with either pro- or anti-inflammatory macrophage markers, whereas TIMP-3 was present in less foamy macrophages and colocalised with CD206. MMP-14 positive macrophages were more abundant whereas TIMP-3 positive macrophages were less abundant in plaques histologically designated as rupture prone. We conclude that foam-cells characterised by high MMP-14 and low TIMP-3 expression are prevalent in rupture-prone atherosclerotic plaques, independent of pro- or anti-inflammatory activation. Therefore reducing MMP-14 activity and increasing that of TIMP-3 could be valid therapeutic approaches to reduce plaque rupture and myocardial infarction.


Assuntos
Macrófagos/metabolismo , Metaloproteinase 14 da Matriz/metabolismo , Placa Aterosclerótica/metabolismo , Inibidor Tecidual de Metaloproteinase-3/metabolismo , Células Cultivadas , Humanos , Imuno-Histoquímica , Ativação de Macrófagos/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
J Aging Stud ; 68: 101216, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38458721

RESUMO

People living with dementia commonly report negative experiences such as disempowerment, stigma, and oppression. Community gardening has demonstrated its potential as a forum for the practice of resistance against the oppressions experienced by other marginalised groups; however, this element of the experience of community gardening has yet to be explored in the context of dementia. A collaboratively-designed community gardening project took place over six weeks, involving six people with dementia. The participants selected all activities undertaken in the garden. Data were collected through semi-structured group interviews with the gardeners and researcher observations. Context-setting semi-structured individual interviews were conducted with four day centre staff members, and three key informants who had experienced working with people with dementia in the garden. The garden acted as a platform for the articulation of both verbal and embodied expressions of resistance against the disempowerment and loss of agency experienced by many people with dementia. The participatory design of the gardening sessions enabled the gardeners to assert their autonomy and independence, and defy the negative stereotypes associated with dementia, which some of the group members appeared to have internalised. Community gardening activities may offer a forum for expressions of resistance against the structures oppressing individuals with dementia. However, in order for this potential to be unlocked, such initiatives must be collaboratively designed, following an approach which recognises the strengths and enduring abilities of people living with dementia. Additionally, the empowering impact of community gardening should not be diluted by positioning the activity as a substitute for adequate statutory health and social care provision, thereby individualising responsibility for the wellbeing of people with dementia.


Assuntos
Demência , Jardinagem , Humanos , Participação da Comunidade
14.
Sociol Health Illn ; 35(4): 529-43, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22897600

RESUMO

In this article we explore the concept of inter-embodiment and its potential for advancing sociological research into illness biography and genetic identity. Inter-embodiment theory views embodied knowledge as produced through relations between bodies, as opposed to originating from within the body or as the product of relations between disembodied selves. Drawing on a qualitative study in which we interviewed 38 individuals about their experiences of discovering they had high cholesterol and undergoing genetic testing for familial hypercholesterolaemia (FH), we discuss how their narratives may be understood from an inter-embodiment perspective. The participants frequently talked at length about their family histories of high cholesterol and cardiovascular disease. Through these accounts, we develop the concept of the family corpus in order to highlight the role body networks play in shaping lay constructions of genetic identity and a familial disease biography. The notion of a family corpus, we argue, is useful in understanding why genetic testing for FH was experienced as either biographical re-enforcement or as biographical disruption. We conclude by discussing the implications of our findings for future sociological research into illness biography and genetic identity.


Assuntos
Testes Genéticos , Conhecimentos, Atitudes e Prática em Saúde , Hipercolesterolemia/diagnóstico , Hipercolesterolemia/genética , Adolescente , Adulto , Idoso , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/psicologia , Colesterol/sangue , Aconselhamento/estatística & dados numéricos , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença/psicologia , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Programas Nacionais de Saúde , Fatores de Risco , Escócia , Classe Social
15.
Hematol Oncol Stem Cell Ther ; 16(4): 397-406, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37363984

RESUMO

BACKGROUND AND OBJECTIVES: The heterogeneous molecular landscape of cytogenetically normal acute myeloid leukemia (CN-AML) renders it an ongoing therapeutic challenge. The European LeukemiaNet (ELN) 2017 guidelines attempted to address this by guiding post-remission therapy according to six prognostically informative mutations. However, its applicability in a South African setting remains unclear due to limited local data. This retrospective study aimed to describe a South African CN-AML cohort according to clinicopathological and molecular features as well as treatment outcomes and, consequently, to investigate the local applicability of a triple-mutation testing approach for risk stratification in accordance with the ELN 2017 guidelines, using nucleophosmin 1 (NPM1), fms-related receptor tyrosine kinase 3 internal tandem duplication (FLT3-ITD), and CCAAT enhancer-binding protein alpha (CEBPA) mutation status. MATERIALS AND METHODS: A review of cytogenetic results for adult de novo AML cases diagnosed at Groote Schuur Hospital between 2005 and 2018 was performed. CN-AML cases were further characterized via a review of clinical and laboratory data and additional molecular testing on stored DNA samples to allow for mutation-based risk stratification and outcome analysis. RESULTS: In total, 218 patients with AML were identified, of which 33% were cytogenetically normal. NPM1, FLT3-ITD, and CEBPA mutations were found in 39%, 34%, and 9% of CN-AML cases, respectively. Retrospective risk stratification according to mutations in these three genes accurately identified both patients at a high risk of induction-resistant disease and those who required an allogeneic stem cell transplant in their first complete remission. CONCLUSION: Local rates of CN-AML and associated NPM1 and FLT3-ITD mutations were comparable to those of European cohorts. Limited mutation analysis in the form of triple-mutation testing proved to be an economical and therapeutically informative prognostication approach for CN-AML in a resource-limited setting.


Assuntos
Leucemia Mieloide Aguda , Proteínas Nucleares , Adulto , Humanos , Proteínas Nucleares/genética , Estudos Retrospectivos , África do Sul , Nucleofosmina , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/tratamento farmacológico , Mutação , Prognóstico
16.
Rev Sci Instrum ; 94(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38109468

RESUMO

Imaging using coherent extreme-ultraviolet (EUV) light provides exceptional capabilities for the characterization of the composition and geometry of nanostructures by probing with high spatial resolution and elemental specificity. We present a multi-modal tabletop EUV imaging reflectometer for high-fidelity metrology of nanostructures. The reflectometer is capable of measurements in three distinct modes: intensity reflectometry, scatterometry, and imaging reflectometry, where each mode addresses different nanostructure characterization challenges. We demonstrate the system's unique ability to quantitatively and non-destructively measure the geometry and composition of nanostructures with tens of square microns field of view and sub-nanometer precision. Parameters such as surface and line edge roughness, density, nanostructure linewidth, and profile, as well as depth-resolved composition, can be quantitatively determined. The results highlight the applicability of EUV metrology to address a wide range of semiconductor and materials science challenges.

17.
J Am Chem Soc ; 134(46): 19129-35, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23116117

RESUMO

We report the first dynamic combinatorial synthesis in water of an all-acceptor [2]catenane and of different types of donor-acceptor [2] and [3]catenanes. Linking two electron-deficient motifs within one building block using a series of homologous alkyl chains provides efficient and selective access to a variety of catenanes and offers an unprecedented opportunity to explore the parameters that govern their synthesis in water. In this series, catenane assembly is controlled by a fine balance between kinetics and thermodynamics and subtle variations in the building block structure, such as the linker length and building block chirality. A remarkable and unexpected odd-even effect with respect to the number of atoms in the alkyl linker is reported.

18.
Int J Lab Hematol ; 44 Suppl 1: 54-63, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36074710

RESUMO

Plasmablastic lymphoma (PBL) is a highly aggressive B cell non-Hodgkin lymphoma frequently associated with immunosuppression, particularly human immunodeficiency virus (HIV) infection. Although PBL is rare globally, South Africa has a high burden of HIV infection leading to a higher incidence of PBL in the region. Laboratory features in PBL may overlap with plasmablastic myeloma and other large B cell lymphomas with plasmablastic or immunoblastic morphology leading to diagnostic dilemmas. There are, however, pertinent distinguishing laboratory features in PBL such as a plasma cell immunophenotype with MYC overexpression, expression of Epstein-Barr virus-encoded small RNAs and lack of anaplastic lymphoma kinase (ALK) expression. This review aims to provide a summary of current knowledge in PBL, focusing on the epidemiology, pathophysiology, laboratory diagnosis and clinical management.


Assuntos
Infecções por Vírus Epstein-Barr , Infecções por HIV , Linfoma Plasmablástico , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/patologia , Infecções por HIV/complicações , Herpesvirus Humano 4 , Humanos , Imunofenotipagem , Linfoma Plasmablástico/diagnóstico , Linfoma Plasmablástico/epidemiologia , Linfoma Plasmablástico/terapia
19.
J Aging Stud ; 59: 100975, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34794720

RESUMO

Developed via an online collaborative writing project involving members of the Multi-species Dementia International Research Network, this article seeks to refocus "the lens of the dementia debate" (Bartlett & O'Connor, 2007) by bringing dementia's complicated relations with the more-than-human world into sharper relief. Specifically, the article explores four thematic areas (contours) within contemporary dementia studies (Care & Caring; Illness Experience & Disease Pathology; Environment, Self & Sustainability; Power, Rights & Social Justice) where the application of multi-species theories and concepts has potential to foster innovation and lead to new ways of thinking and working. Whilst incorporating multi-species perspectives within dementia studies can create new ways of responding and new spaces of response-ability, the potential for conflict and controversy remains high. It is imperative, therefore, that the field of dementia studies not only becomes a site within which multi-species perspectives can flourish, but that dementia studies also becomes a vehicle through which multi-species concepts may be refined.


Assuntos
Demência , Humanos , Justiça Social , Inquéritos e Questionários
20.
Animals (Basel) ; 11(8)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34438806

RESUMO

To reduce the spread of COVID-19, countries worldwide placed limitations on social interaction, which is anticipated to have severe psychological consequences. Although findings are inconsistent, prior research has suggested that companion animals may positively influence human well-being and reduce loneliness. In the context of COVID-19, this has important implications, as companion animal guardians may be less negatively affected by the pandemic. The primary aim of this research was to investigate the influence of companion animals on mental well-being and loneliness during the pandemic, with specific interest in the role of ornamental fishes. A mixed-methods study was conducted, using an international sample. Quantitative data were collected via an online survey (n = 1199) and analysed using robust hierarchical multiple regression analyses; the influence of level of engagement with companion animals was examined for dogs, cats and ornamental fishes. There was no evidence that companion animal guardianship was associated with loneliness and mental well-being during the pandemic but spending more time engaging physically or socially with dogs (and to a lesser extent cats) was generally associated with poorer outcomes. Qualitative data were collected through open-ended survey responses (n = 757) and semi-structured interviews (n = 25) and analysed using reflexive thematic analysis. Two themes were developed-one related to companion animals as providers of social and emotional support, and the other to companion animals as providers of purpose and perspective. Concerns regarding the impact of the pandemic on animal welfare were also identified. Compared to other animal types, more participants expressed indifference regarding the impact of their fishes on their well-being during the pandemic, possibly because fishes cannot provide comfort via physical touch. The findings of this study reflect the wider field of human-animal interaction; although qualitative data suggest guardians believe their companion animals are a positive influence in their lives, there is little convincing quantitative data to support these beliefs. This highlights the need to refine theories regarding which aspects of companion animal guardianship may influence human well-being; the findings from this research may be useful in the refinement of such theories.

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