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1.
Rep Prog Phys ; 81(4): 046501, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29266004

RESUMO

This review stands in the larger framework of functional materials by focussing on heterostructures of rare-earth nickelates, described by the chemical formula RNiO3 where R is a trivalent rare-earth R = La, Pr, Nd, Sm, …, Lu. Nickelates are characterized by a rich phase diagram of structural and physical properties and serve as a benchmark for the physics of phase transitions in correlated oxides where electron-lattice coupling plays a key role. Much of the recent interest in nickelates concerns heterostructures, that is single layers of thin film, multilayers or superlattices, with the general objective of modulating their physical properties through strain control, confinement or interface effects. We will discuss the extensive studies on nickelate heterostructures as well as outline different approaches to tuning and controlling their physical properties and, finally, review application concepts for future devices.

2.
Nano Lett ; 15(11): 7355-61, 2015 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-26484628

RESUMO

The functional properties of oxide heterostructures ultimately rely on how the electronic and structural mismatches occurring at interfaces are accommodated by the chosen materials combination. We discuss here LaMnO3/LaNiO3 heterostructures, which display an intrinsic interface structural asymmetry depending on the growth sequence. Using a variety of synchrotron-based techniques, we show that the degree of intermixing at the monolayer scale allows interface-driven properties such as charge transfer and the induced magnetic moment in the nickelate layer to be controlled. Further, our results demonstrate that the magnetic state of strained LaMnO3 thin films dramatically depends on interface reconstructions.

3.
Equine Vet J ; 43(3): 259-64, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21492201

RESUMO

REASON FOR PERFORMING STUDY: By study of the translocation and deformation of equine menisci throughout the range of motion, it may be possible to identify potential mechanical factors in the pathogenesis of injury to the cranial horn of the medial meniscus. OBJECTIVE: To quantitatively document meniscal translocation and deformation using radiographic and MR imaging, and to evaluate for potential variation between the medial and lateral menisci. METHODS: Radiographic markers were embedded in the periphery of the menisci in 6 cadaver stifles. Proximal-distal radiographs were taken at 15° intervals ranging from full flexion (30°) to full extension (160°). Magnetic resonance imaging sequences of 3 additional cadaver stifles were obtained in axial and sagittal planes at the predetermined stifle angles. RESULTS: A significantly greater overall mean cranial-caudal translocation (1.6 times) of the lateral meniscus relative to the medial was seen from full extension to full flexion (P = 0.002). The cranial horn of the medial meniscus was the least mobile of the 4 horns, yet a significant cranial displacement relative to the cranial horn of the lateral meniscus was seen in the terminal 10° of extension. MRI images revealed a significantly greater axial compressive strain in the cranial horn of the medial meniscus relative to the cranial horn of the lateral meniscus in the terminal 10° of extension (P = 0.017). CONCLUSION: The equine menisci exhibit a cranial-caudal translocation over the tibia throughout the range of motion. While the cranial horn of the medial meniscus is the least mobile of the 4 horns, it undergoes significant cranial translocation and axial compression in the terminal 10° of extension. POTENTIAL RELEVANCE: Hyperextension of the stifle may place the cranial horn of the medial meniscus at risk of injury and thus explain the higher prevalence of meniscal tears at this location.


Assuntos
Cavalos/anatomia & histologia , Cavalos/fisiologia , Amplitude de Movimento Articular/fisiologia , Joelho de Quadrúpedes/anatomia & histologia , Joelho de Quadrúpedes/fisiologia , Animais , Fenômenos Biomecânicos , Cadáver , Radiografia , Joelho de Quadrúpedes/diagnóstico por imagem
4.
Equine Vet J ; 43(3): 265-9, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21492202

RESUMO

REASONS FOR PERFORMING THE STUDY: The conventional arthroscopic approach to the palmar/plantar aspect of the distal interphalangeal joint (DIPJ) may result in the inadvertent penetration of the digital flexor tendon sheath (DFTS) and the navicular bursa (NB). This iatrogenic communication would be undesirable subsequent to arthroscopic lavage of a septic DIPJ. HYPOTHESIS: A lateral/medial approach to the palmar/plantar aspect of the DIPJ will result in a significantly lower rate of inadvertent penetration of the DFTS and NB, whilst still providing adequate intra-articular evaluation. METHODS: The conventional palmar/plantar approach or a novel lateral/medial approach to the DIPJ was performed on cadaver fore- and hindlimbs (30 limbs/approach). Subsequently, India ink was injected into the dorsal pouch of the DIPJ, and the DFTS (n = 60) and NB (n = 20) were examined for the presence/absence of ink. In addition, observations of the number of attempts made to access the joint, evidence of iatrogenic intra-articular trauma and occurrence of incomplete visualisation of the palmar/plantar pouch were recorded. RESULTS: With the conventional approach, DFTS penetration was noted in 18/30 (60%) of the limbs, compared to 1/30 (3.3%) with the lateral/medial approach (P≤0.001). NB penetration was seen in 5/10 limbs with the palmar/plantar approach compared to 0/10 with the lateral/medial approach (P = 0.01). No significant differences were found between the approaches in the number of attempts made to access the joint, the incidence of iatrogenic intra-articular trauma, or the occurrence of incomplete visibility of the palmar/plantar pouch. CONCLUSIONS: The novel lateral/medial approach to the DIPJ significantly decreases the risk of inadvertent penetration of the DFTS and NB. POTENTIAL RELEVANCE: The novel lateral/medial approach to the DIPJ is an effective technique to gain access to the palmar/plantar pouches, and is particularly advantageous for arthroscopic lavage of a septic DIPJ.


Assuntos
Artroscopia/veterinária , Cavalos , Articulações/cirurgia , Animais , Artroscopia/métodos , Cadáver , Membro Anterior
5.
BMC Sports Sci Med Rehabil ; 13(1): 58, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34049581

RESUMO

BACKGROUND: Throughout the ecosystem of sport, women have been and continue to be underrepresented at all levels compared to men. The capacity of community-level sport is heavily reliant on the many non-player roles including governance, as well as administration, coaching and officiating. Recently there has been increased attention to improving the gender balance in sport. The aim of this study is to investigate the proportions of women engaged in non-playing roles in sport (2016-2018). METHODS: This study involved secondary analysis of the AusPlay survey, a national population survey, funded by Sport Australia. This study utilised data from people aged 15-years or older about their involvement in non-playing roles in sport, and their demographic data. Survey respondents were asked "During the last 12 months, have you been involved with any sports in a nonplaying role, such as official, coach, referee, administrator, etc?" Analysis of non-player role responses focussed specifically on the top four non-player role categories; coach, official, administrator and manager. Frequency analysis concentrated on the distribution of men and women involvement in a non-player capacity for the three years, with detailed analysis of the most recent year (2018). RESULTS: In this study of 61,578 Australians there was a higher proportion of men in non-player roles in sport compared to women, across each of the three years (2018: men 55 %, women 46 %). Involvement of women in coaching increased significantly from 38 % to 2016 to 44 % in 2018 (p < 0.001). The proportion of women involved in administration roles significantly decreased from a peak of 51 % in 2017 to 46 % in 2018 (p < 0.001). CONCLUSIONS: Aligned with strategic policy and investment strategies, there are gradual increased representation of women in non-playing sport, coaching roles. Women are still underrepresented in terms of coaches, officials and administrators, but are more likely to be managers. It is recommended that there is continued mentoring, identification and emphasising of female role models, and further strategies to increase female presence in non-playing roles. We recommend that future research, in line with appropriate gender and cultural-change theories, investigates and discusses the progress of gender equality throughout playing and non-playing role in sport.

6.
Equine Vet J ; 51(1): 52-56, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29761574

RESUMO

BACKGROUND: Hyperinsulinaemia is the suspected component of insulin dysregulation having the strongest association with laminitis and occurs variably in equids with pituitary pars intermedia dysfunction (PPID). OBJECTIVES: We hypothesised that magnitude of hyperinsulinaemia correlates with laminitis severity in PPID-affected equids. Furthermore, we hypothesised that owners can be unaware of chronic endocrinopathic laminitis. STUDY DESIGN: Cross-sectional study. METHODS: Serum insulin concentrations, owner-reported laminitis history and radiographic evidence of laminitis were determined in 38 client-owned horses and ponies with confirmed PPID. Laminitis severity was classified into four categories (normal [nonlaminitic], mild, moderate or severe laminitis) based on degree of distal phalangeal rotation. Animals were also categorised as normoinsulinaemic (<20 µU/ml), mildly hyperinsulinaemic (20-50 µU/ml) and severely hyperinsulinaemic (>50 µU/ml). One-way ANOVA, t tests and Fisher's exact tests were performed. RESULTS: While owners reported laminitis in 37% of animals, 76% were laminitic based on study criteria (P = 0.01). Owners reported laminitis more frequently in hyperinsulinaemic vs. normoinsulinaemic animals; recognition increased with severity of hyperinsulinaemia (P = 0.03). Mean insulin concentrations were higher in equids with moderate to severe radiographic laminitis (geometric mean 74.1, 95% confidence interval (CI) 38.4-143.1 uU/ml) vs. those classified radiographically as normal to mild (31.9, 95% CI 21.1-48.1 uU/ml P = 0.03). MAIN LIMITATIONS: Dynamic insulin testing was not performed; some normoinsulinaemic animals might have had subtle insulin dysregulation. CONCLUSIONS: Although radiographic abnormalities were present in most animals at the time of PPID diagnosis, chronic laminitis remained unrecognised by many owners. Owner awareness of laminitis increased with severity of hyperinsulinaemia and higher insulin concentrations were detected in association with more severe radiographic changes. The Summary is available in Chinese - See Supporting Information.


Assuntos
Doenças do Pé/veterinária , Casco e Garras/patologia , Doenças dos Cavalos/diagnóstico , Hiperinsulinismo/veterinária , Doenças da Hipófise/veterinária , Adeno-Hipófise Parte Intermédia/fisiopatologia , Hormônio Adrenocorticotrópico/sangue , Análise de Variância , Animais , Estudos Transversais , Feminino , Doenças do Pé/diagnóstico por imagem , Doenças do Pé/patologia , Doenças dos Cavalos/patologia , Doenças dos Cavalos/fisiopatologia , Cavalos , Hidrocortisona/sangue , Hiperinsulinismo/complicações , Insulina/sangue , Doenças da Hipófise/complicações , Doenças da Hipófise/diagnóstico , Doenças da Hipófise/fisiopatologia , Índice de Gravidade de Doença
7.
Equine Vet J ; 44(5): 554-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22168479

RESUMO

REASON FOR PERFORMING THE STUDY: To identify potential functional-anatomical characteristics of the cranial horn attachment of the medial meniscus (MM) that may help explain the pathogenesis of the common tear patterns that have been reported. HYPOTHESIS: Full extension of the stifle generates a significant increase in tensile forces within the cranial meniscotibial ligament (CrMTL) of the MM, which may predispose this structure to injury. METHODS: The effect of femorotibial angle (160°, 150°, 140° and 130°) on tensile forces in the axial and abaxial components of the CrMTL was examined in 6 mature cadaver stifles using an implantable force probe. Three additional specimens were used to examine the histological structure of the CrMTL and its connection to the cranial horn of the MM. RESULTS: Full extension of the stifle (160°) resulted in a significantly greater tensile force in the abaxial component of the CrMTL when compared with the axial component (P = 0.001). The tensile force in the abaxial component of the CrMTL increased significantly between 150° and 160° of stifle extension (P = 0.011). The CrMTL appears to be comprised of 2 functional components, which become more visually distinct as the stifle is extended. Histologically, these components are separated by a cleft of highly vascularised, less organised connective tissue, which becomes less prominent at the junction of the ligament and the cranial horn of the MM. CONCLUSION: A 4-fold difference in the tensile forces in the 2 functional components of the CrMTL of the MM was observed with full extension of the stifle. POTENTIAL RELEVANCE: The functional anatomy of the CrMTL may place this region at greater risk of injury during hyperextension of the stifle and, therefore, may provide a mechanistic rationale for the commonly reported meniscal tear patterns in the horse.


Assuntos
Ligamentos/fisiologia , Meniscos Tibiais/fisiologia , Joelho de Quadrúpedes/fisiologia , Animais , Fenômenos Biomecânicos , Cadáver , Feminino , Cavalos , Masculino , Meniscos Tibiais/patologia
8.
Histol Histopathol ; 21(7): 687-96, 2006 07.
Artigo em Inglês | MEDLINE | ID: mdl-16598667

RESUMO

Bacterial lipopolysaccharides (LPS) initiate immune response through Toll-like receptor 4 (TLR4). Because many a times host is confronted with secondary bacterial challenges, it is critical to understand TLR4 expression following initial provocation. We studied TLR4 expression in rats at various times after intra-tracheal instillation of LPS. Although TLR4 mRNA was undetectable in normal lungs, it increased at 6h and 12h and declined at 36h post-LPS treatment. Western blots showed TLR4 protein at all time points. Immunohistochemistry localized TLR4 in alveolar septal cells, bronchial epithelium, macrophages and endothelium of large and peribronchial blood vessels. Dual label immunoelectron microscopy showed co-localization of TLR4 and LPS in the cytoplasm and nucleus of various lung and inflammatory cells. Nuclear localization of TLR4 was confirmed with Western blots on lung nuclear extracts. We conclude that TLR4 expression in lung is sustained up to 36 hours and that TLR4 and LPS are localized in the cytoplasm and nuclei of lung cells.


Assuntos
Imunidade Celular/imunologia , Pulmão/metabolismo , Pneumonia/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Western Blotting , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Núcleo Celular/ultraestrutura , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Citoplasma/ultraestrutura , Modelos Animais de Doenças , Escherichia coli/imunologia , Técnicas Imunoenzimáticas , Lipopolissacarídeos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Pneumonia/induzido quimicamente , Pneumonia/patologia , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Organismos Livres de Patógenos Específicos , Receptor 4 Toll-Like/genética
9.
Anaesth Intensive Care ; 33(6): 805-7, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16398389

RESUMO

The present report describes two similar thoracoscopic procedures performed on the same 81-year-old male patient. Because acute hypoxia had developed during one-lung ventilation on the first occasion, serial blood gases were taken during the second. Also, whereas on the first occasion the non-ventilated lung had been left open to air when one-lung ventilation was initiated, on the second it was connected to an ambient pressure oxygen source with the object of theoretically enabling apnoeic oxygenation during lung collapse. It is argued that this fundamental difference in anaesthetic practice may have contributed to the improved oxygenation that was recorded during the second thoracoscopy.


Assuntos
Oxigenoterapia/métodos , Oxigênio/sangue , Respiração com Pressão Positiva , Ventilação Pulmonar/fisiologia , Idoso , Idoso de 80 Anos ou mais , Anestesia por Inalação/métodos , Gasometria , Seguimentos , Humanos , Masculino , Medição de Risco , Cirurgia Torácica Vídeoassistida/efeitos adversos , Cirurgia Torácica Vídeoassistida/métodos , Toracoscopia/métodos , Resultado do Tratamento
10.
Postgrad Med J ; 66(777): 573-5, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2217020

RESUMO

A case of skin necrosis at the sites of injection of subcutaneous heparin is described. The patient went on to develop heparin-induced thrombocytopenia and pulmonary embolism. Review of the previously described cases of heparin-associated skin necrosis reveals that this sequence of events is not uncommon.


Assuntos
Heparina/efeitos adversos , Pele/patologia , Feminino , Heparina/administração & dosagem , Humanos , Injeções Subcutâneas , Pessoa de Meia-Idade , Necrose , Embolia Pulmonar/induzido quimicamente , Trombocitopenia/induzido quimicamente
11.
Health Bull (Edinb) ; 47(1): 9-12, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2703346

RESUMO

Two studies involving eighty women having treatment with artificial insemination by donor (AID) have demonstrated that the use of a urinary semi-quantitative assay for luteinising hormone (LH) gives pregnancy rates comparable to those obtained using plasma LH for the timing of insemination. The advantage of self test assay is evident in a scattered region such as Grampian.


Assuntos
Inseminação Artificial Heteróloga , Inseminação Artificial , Ovulação , Adulto , Feminino , Humanos , Hormônio Luteinizante/sangue , Hormônio Luteinizante/urina , Gravidez , Kit de Reagentes para Diagnóstico , Escócia
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