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1.
Rev Sci Instrum ; 93(11): 113105, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36461526

RESUMO

X-ray Compton spectroscopy is one of the few direct probes of the electron momentum distribution of bulk materials in ambient and operando environments. We report high-resolution inelastic x-ray scattering experiments with high momentum and energy transfer performed at a storage-ring-based high-energy x-ray light source facility using an x-ray transition-edge sensor (TES) microcalorimeter detector. The performance was compared with a silicon drift detector (SDD), an energy-resolving semiconductor detector, and Compton profiles were measured for lithium and cobalt oxide powders relevant to lithium-ion battery research. Spectroscopic analysis of the measured Compton profiles demonstrates the high-sensitivity to the low-Z elements and oxidation states. The line shape analysis of the measured Compton profiles in comparison with computed Hartree-Fock profiles is usually limited by the resolution of the semiconductor detector. We have characterized an x-ray TES microcalorimeter detector for high-resolution Compton scattering experiments using a bending magnet source at the Advanced Photon Source with a double crystal monochromator, providing monochromatic photon energies near 27.5 keV. The momentum resolution below 0.16 atomic units (a.u.) was measured, yielding an improvement of more than a factor of 7 over a state-of-the-art SDD for the same scattering geometry. Furthermore, the lineshapes of narrow valence and broad core electron profiles of sealed lithium metal were clearly resolved using an x-ray TES compared to smeared and broadened lineshapes observed when using the SDD. High-resolution Compton scattering using the energy-resolving area detector shown here presents new opportunities for spatial imaging of electron momentum distributions for a wide class of materials with applications ranging from electrochemistry to condensed matter physics.

2.
Cardiovasc Eng Technol ; 6(1): 36-48, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26577101

RESUMO

End-to-side vascular anastomosis has a considerable complexity regarding the suturing of the juncture line between the artery and the graft. The present study proposes a stress-concentration methodology for the prediction of the stress distribution at the juncture line, aiming to provide generic expressions describing the response of an end-to-side anastomosis. The proposed methodology is based on general results obtained from the analysis of pipe connections, a topic that has been investigated in recent years in the field of offshore structural engineering. A key aspect for implementing the stress-concentration-factor approach is the recognition that the axial load due to pressure and flow dynamics exerted along the graft axis controls the "hot spots" on the juncture line, which in turn affects the mechanical response of the sutures. Several parameters, identified to influence the suture line response, are introduced in closed-form expressions for the suture line response calculations. The obtained results compare favorably with finite element results published in the literature. The proposed model predicts analytically the suture line response of end-to-side anastomosis, while capturing the influence of and interdependence among the problem parameters. Lower values of the graft radius, the distance between sequential stitches, and the intersecting angle between the artery and the graft are some of the key parameters that reduce the suture line response. The findings of this study are broad in scope and potentially applicable to improving the end-to-side anastomosis technique through improved functionality of the sutures and optimal selection of materials and anastomosis angle.


Assuntos
Anastomose Cirúrgica/métodos , Artérias/fisiopatologia , Artérias/cirurgia , Modelos Cardiovasculares , Pressão Arterial , Prótese Vascular , Humanos , Estresse Mecânico , Suturas
3.
Open Biomed Eng J ; 9: 1-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25949745

RESUMO

Suture line stress concentration and intimal hyperplasia are related to the long-term complications of end-toside and side-to-side anastomosis. Several factors, such as hemodynamic effects, biological activities and the mechanical properties of the blood vessels, are identified to influence the problem. Yet, it is not completely clear which are the factors that influence most the long-term complications and in what specific way. This study aims to examine if elastic (compliance) mismatch increases the stress concentration and intimal thickening at the suture line. Better compliance may be obtained by using grafts with similar mechanical properties to the host artery or by anastomosis techniques that utilize vein patches and cuffs (Taylor-patch and Miller-cuff anastomosis). The anastomosis model used in this study is a circular cylindrical system consisting of two semi-cylinders, interconnected by two hinges. The internal blood pressure is applied on the arterial walls. The static and dynamic responses are analytically derived in terms of radial and tangential displacements, internal forces and strains of the two blood vessels and rotation of their cross-section. Results suggest that increased elastic mismatch between the artery and the graft may promote elevated intimal thickening due to large incompatible angles at the junction, whereas there is no correlation between elastic mismatch and elevated stress concentration at the suture line. Another interesting application of the present model is the patching of arteries as applied in carotid endarterectomy.

4.
Ann Oncol ; 24 Suppl 7: vii41-47, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24001762

RESUMO

This article introduces palliative care to cancer patients in Middle Eastern countries. It considers the importance of the multidisciplinary team in providing an adequate service to the patient and his/her family. It provides views of professionals from the various countries with regard to the role of the nurse in such teams; whereby the three elements of palliative care nursing entail: 1. Working directly with patients and families; 2. Working with other health and social care professionals to network and co-ordinate services; and 3. working at an organizational level to plan, develop and manage service provision in local, regional and national settings. This article also details the challenges that nurses face in the Middle East and outlines the preferable ways to overcome such challenges. The latter include more focused educational activities at the undergraduate and graduate levels and continuous clinical training throughout their work as palliative care nurse specialists.


Assuntos
Enfermagem de Cuidados Paliativos na Terminalidade da Vida , Neoplasias/terapia , Equipe de Assistência ao Paciente , Envelhecimento , Humanos , Oriente Médio , Enfermeiras e Enfermeiros , Cuidados Paliativos
5.
Ann Oncol ; 24 Suppl 7: vii5-10, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24001764

RESUMO

Cancer is now the fastest growing killing disease in the Middle East. Accordingly, there is an urgent need to train local health professionals: oncologists, palliative care experts, oncology nurses, psychologists, along with social workers, physiotherapists and spiritual counselors on strategies for early detection, curative therapies and palliation. Professionals in the region, along with the public, need to convince medical administrators, regulators and policymakers about investing in education and training of YOUNG professionals, as well as those with already proven experience in cancer care. Training is the basis for any future cancer care program, which aims at the integration of palliative care practices into standard oncology care across the trajectory of the illness.


Assuntos
Educação Médica , Necessidades e Demandas de Serviços de Saúde , Neoplasias/terapia , Cultura , Educação Médica/economia , Educação Médica/estatística & dados numéricos , Educação Médica/tendências , Pessoal de Saúde , Humanos , Oriente Médio , Relações Médico-Paciente , Atenção Primária à Saúde , Resultado do Tratamento
6.
Ann Oncol ; 23 Suppl 3: 15-28, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22628412

RESUMO

BACKGROUND: In larger parts of the Middle East palliative care is still misunderstood among health professionals, cancer patients and the public at large. One reason to that is because the term does not obviously communicate the intent of this clinical discipline, which is lending better quality of life while combating cancer. Further, culture, tradition and religion have contributed to this misgiving and confusion especially at the terminal stage of the disease. METHODS: The Middle East Cancer Consortium jointly with the American Society of Clinical Oncology, the American Oncology Nursing Society, the San Diego Hospice Center for Palliative Medicine and the Children's Hospital & Clinics of Minnesota initiated a series of training courses and workshops in the Middle East to provide updated training to physicians, nurses, social workers and psychologists from throughout the region with basic concepts of palliative care and pain managements in adults and children cancers. RESULTS: During the past 6 years hundreds of professionals took part in these educational and training activities, thereby creating the core of trained caregivers who start to make the change in their individual countries. CONCLUSIONS: The outcome of consecutive training activities can overcome geopolitical instabilities, and yield a genuine change in approach of both regulators, medical administrators, medical staff and the public; as to the important contribution of palliative care services to the welfare of the patient and his/her family.


Assuntos
Neoplasias/terapia , Cuidados Paliativos/métodos , Analgésicos Opioides/uso terapêutico , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Oriente Médio , Neoplasias/complicações , Dor/tratamento farmacológico , Dor/etiologia , Cuidados Paliativos/tendências
7.
Ann Oncol ; 23 Suppl 3: 79-83, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22628422

RESUMO

BACKGROUND: Prescription of opioids based on morphine equivalence data per capita is very low in Cyprus. Three studies were undertaken to evaluate the prescribing habits of physicians in Cyprus for cancer patients with pain. METHODS: Data were collected regarding the presence and severity of pain and prescription of analgesia in a cross-sectional study of 141 patients receiving outpatient chemotherapy within the Bank of Cyprus Oncology Centre (BOCOC), in a retrospective study of 90 new lung cancer patients referred to one Oncologist in the BOCOC, and in a prospective study of 100 new cancer patients referred to the BOCOC. In the first study, the results reflected the prescribing habits of oncologists within the oncology centre, whilst the second and third studies reflected the prescribing habits of physicians outside the oncology centre. RESULTS: In the three studies, 56.0%, 48.1% and 57.7%, respectively, of patients with pain were prescribed analgesia. The majority of patients were prescribed paracetamol and non-steroidal anti-inflammatory drugs, and only 8.6%, 11.5% and 0%, respectively, of patients were prescribed strong opioids. In the last two studies, following their oncology appointment the prescription of analgesia to patients with pain, increased to 80.8% and 73.1%, respectively, whilst the prescription of strong opioids, increased to 28.8% and 34.6%, respectively, reflecting oncologists' practice. CONCLUSION: There is under-treatment of pain in cancer patients, both within and outside a tertiary oncology centre in Cyprus. Particularly there is low prescribing of strong opioids. There is a need to look further into the barriers that prevent physicians prescribing opioids in Cyprus, as well as to patients' attitudes towards analgesia and opioids, and to set up training programs to address these issues.


Assuntos
Analgésicos/uso terapêutico , Neoplasias/complicações , Dor/tratamento farmacológico , Padrões de Prática Médica/estatística & dados numéricos , Adolescente , Adulto , Estudos Transversais , Chipre , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Estudos Retrospectivos , Adulto Jovem
9.
Clin Oncol (R Coll Radiol) ; 12(3): 192-3, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10942338

RESUMO

We report the case history of a patient with a known history of psoriasis, who developed an exacerbation of the treated skin area after radiotherapy for carcinoma of the breast. This illustrates the Koebner phenomenon, with the replication of a dermatosis at the site of skin trauma.


Assuntos
Neoplasias da Mama/radioterapia , Carcinoma/radioterapia , Psoríase/complicações , Radioterapia/efeitos adversos , Neoplasias da Mama/complicações , Neoplasias da Mama/patologia , Carcinoma/complicações , Carcinoma/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Psoríase/patologia
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