Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 62
Filtrar
1.
Rev Sci Instrum ; 92(5): 054504, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243263

RESUMO

In the last few decades, much effort has been made for the production of squeezed vacuum states in order to reduce quantum noise in the audio-frequency band. This technique has been implemented in all running gravitational-wave interferometric detectors and helped to improve their sensitivity. While the detectors are acquiring data for astrophysical observations, they must be kept in the operating condition, also called "science mode," that is, a state that requires the highest possible duty-cycle for all the instrumental parts and controls. We report the development of a highly automated setup for the generation of optical squeezed states, where all the required control loops are supervised by a software based on finite state machines; we took special care to grant ease of use, stability of operation, and possibility of auto-recovery. Moreover, the setup has been designed to be compatible with the existing software and hardware infrastructure of the Virgo detector. In this paper, we discuss the optical properties of this squeezing setup, the locking techniques, and the automation algorithms.

2.
Rev Sci Instrum ; 91(7): 074712, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32752818

RESUMO

A module of a wireless high voltage generator was tested immersed in both gaseous and liquid environments providing electrical insulation. The overall performance of the module as well as a detailed performance of the key components are reported, and a comparison between the results in gas and liquid is given. The tests performed on the liquid dielectric show that it is a valid alternative to high pressure gas electrical insulation.

3.
Proc Biol Sci ; 286(1905): 20190718, 2019 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-31213186

RESUMO

Neonicotinoids are effective insecticides used on many important arable and horticultural crops. They are nicotinic acetylcholine receptor agonists which disrupt the function of insect neurons and cause paralysis and death. In addition to direct mortality, there are numerous sublethal effects of low doses of neonicotinoids on bees. We hypothesize that some of these large array of effects could be a consequence of epigenetic changes in bees induced by neonicotinoids. We compared whole methylome (BS-seq) and RNA-seq libraries of the brains of buff-tailed bumblebee Bombus terrestris workers exposed to field-realistic doses of the neonicotinoid imidacloprid to libraries from control workers. We found numerous genes which show differential expression between neonicotinoid-treated bees and control bees, but no differentially methylated cytosines in any context. We found CpG methylation to be focused mainly in exons and associated with highly expressed genes. We discuss the implications of our results for future legislation.


Assuntos
Abelhas/fisiologia , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Testes de Toxicidade , Animais , Metilação de DNA/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos
4.
Philos Trans A Math Phys Eng Sci ; 377(2137)2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30530541

RESUMO

A short description of the muon tomography demonstrator at the INFN Laboratori Nazionali di Legnaro near Padua, Italy, is given and the principal achievements owing to the data collected at that experimental facility are presented. In particular, the feasibility studies for several applications based on the muon-tomographic technology, within national and European projects, are discussed. The experimental problems and the procedures used to improve the performance are underlined. In addition, new activities and the related detector optimization are illustrated.This article is part of the Theo Murphy meeting issue 'Cosmic-ray muography'.

5.
Rev Sci Instrum ; 88(2): 025113, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28249465

RESUMO

A high voltage generator built by a series connection of 100 kV modules was produced. The series connection feasibility is ensured by the inherent floating character of each module which is wireless powered by high efficiency photovoltaic cells illuminated by a laser system. Each module is equipped with a control and monitoring board allowing excellent stabilization of the high voltage output. The performance of the system in terms of reliability, stability, and efficiency was evaluated. In particular using a three module setup, we achieved a maximum voltage of 234 kV with stability better than 0.1%.

6.
Radiat Prot Dosimetry ; 175(2): 260-266, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27881795

RESUMO

A multi-element tissue-equivalent proportional counter (TEPC), based on a single gas electron multiplier (GEM) foil of standard geometry, has been constructed with 16 cylindrical sensitives volumes. In this article, the design of this novel counter is described and first microdosimetric measurements are presented. To study the response of the GEM-TEPC to both low and high linear energy transfer radiation fields, the microdosimetric spectra due to a 137Cs gamma-ray source and to fast neutrons from 7Li(d,n)8Be reaction have been measured using pure propane gas at low pressure, in order to simulate a tissue site of about 1 µm equivalent size. The comparison with spectra measured with a spherical TEPC and with a mini-TEPC demonstrates promising properties for application of the GEM-TEPC for microdosimetric applications.


Assuntos
Elétrons , Proteção Radiológica , Desenho de Equipamento , Humanos , Nêutrons , Doses de Radiação , Radiometria , Eficiência Biológica Relativa
7.
Rev Sci Instrum ; 84(2): 024701, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23464232

RESUMO

The feasibility of fully floating high voltage (HV) generation was demonstrated producing a prototype of a modular HV system. The primary power source is provided by a high efficiency semiconductor power cell illuminated by a laser system ensuring the floating nature of each module. The HV is then generated by dc-dc conversion and a HV multiplier. The possibility of series connection among modules was verified.


Assuntos
Equipamentos e Provisões Elétricas , Dispositivos Ópticos , Condutividade Elétrica
8.
Ann Trop Med Parasitol ; 105(8): 617-23, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22325821

RESUMO

In patients with Strongyloides stercoralis infection, a dysregulation of host immunity can lead to hyperinfection syndrome (HS) and disseminated strongyloidiasis (DS), characterized by high fatality rate. HS has been reported in HIV-positive patients following use of corticosteroids or during immune reconstitution inflammatory syndrome (IRIS). A retrospective study was conducted to estimate the prevalence of S. stercoralis infection among HIV-positive immigrants, attending two Italian hospitals. From January 2000 to August 2009, 138 HIV-positive immigrants were systematically screened for strongyloidiasis, as a part of their routine care, with an indirect immunofluorescent antibody test (IFAT) developed at the Centre for Tropical Diseases, Sacro Cuore Hospital of Negrar, Verona. The majority were also submitted to stool examination. Fifteen (11%) resulted infected by S. stercoralis, of whom four (27%) had a negative serology (diagnosis made with stool examination). A higher eosinophil count (0·94 versus 0·24×10(9)/l, P<0·01) and more frequent gastrointestinal and cutaneous symptoms (odds ratio: 4·8 and 5·8, respectively) were found in patients with strongyloidiasis compared with controls. The IFAT is more sensitive than direct parasitological methods. The proportion of false negative results was higher than expected based on the theoretical test sensitivity. Considering the high prevalence detected and the apparent, lower sensitivity of serology, we propose a systematic screening for Strongyloides infection, with both serology and stool culture, for all HIV-positive immigrants coming from endemic areas.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/etnologia , Strongyloides stercoralis , Estrongiloidíase/etnologia , Infecções Oportunistas Relacionadas com a AIDS/complicações , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/imunologia , Adulto , Animais , População Negra/estatística & dados numéricos , Contagem de Linfócito CD4 , Emigrantes e Imigrantes/estatística & dados numéricos , Reações Falso-Negativas , Fezes/parasitologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo/métodos , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Estrongiloidíase/complicações , Estrongiloidíase/diagnóstico , Estrongiloidíase/imunologia , Adulto Jovem
9.
Electromyogr Clin Neurophysiol ; 43(6): 367-72, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14535049

RESUMO

The aim of this study was to analyze electromyographically the upper and lower fascicles of the orbicularis oris muscle in deaf patients comparing them with clinically normal patients. These patients present several disorders in facial muscles, temporomandibular joints disorders and constantly headache in virtue of not the use of the face expression muscles. This was performed in 30 patients from both sexes with a mean age of 18.5 years, divided into 3 groups of 10 patients each: 1. deaf patients with buccal breathing and incompetent lips; 2. in deaf patients with nasal breathing and competent lips; 3. clinically normal patients, in 7 clinical conditions: at rest with and without labial contact, sucking water, blowing, pursing and reciprocal compression of the lips and the emission of the syllabi "PA". It was observed that in the deaf patients group, both fascicles of the orbiculares oris muscles presented hyperactivity in most of the analyzed movements, mainly in buccal breathing with incompetent lips, and the lower fascicle demonstrated the highest electromyographic activity.


Assuntos
Surdez/fisiopatologia , Músculos Faciais/fisiologia , Adolescente , Adulto , Eletromiografia , Feminino , Humanos , Masculino
10.
Circulation ; 103(4): 549-54, 2001 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-11157721

RESUMO

BACKGROUND: Cytokines released by activated T lymphocytes are key regulators of chronic inflammatory response, including atherosclerosis. The aim of this study was to investigate the presence of interleukin-3 (IL-3) in lymphocytes infiltrating the atherosclerotic plaque and the effect of this cytokine on primary vascular smooth muscle cells (SMCs). METHODS AND RESULTS: Twenty atherosclerotic carotid arterial specimens and 5 early atherosclerotic lesions from the internal carotid were manually minced to fragments, and T lymphocytes infiltrating the atherosclerotic plaque were isolated on solid-phase anti-CD3 polystyrene plates. Southern blot analysis demonstrated that in all samples, lymphocytes expressed IL-3 and IL-2 receptor alpha-chain transcripts, indicating that in this context, the activated T lymphocytes may release IL-3. We further analyzed the expression of the IL-3 receptor and the biological effects exerted by the ligand on vascular SMCs. ss-IL-3-transducing subunit was detected both on cultured SMCs and on endothelial cells and SMCs within atheroma. The analysis of the IL-3-induced biological effects demonstrated that it was able to trigger both mitogenic and motogenic signals. Moreover, we demonstrated that the addition of PD98059, a known inhibitor of the MAP-extracellular signaling-regulated/MAP kinase pathway, completely inhibited IL-3-mediated MAP kinase activation and IL-3-induced migration and proliferation. Finally, IL-3 was found to stimulate vascular endothelial growth factor (VEGF) gene transcription. CONCLUSIONS: IL-3, expressed by activated T lymphocytes infiltrating early and advanced atherosclerotic plaques, may sustain the atherosclerotic process either directly, by activating SMC migration and proliferation, or indirectly, via VEGF production.


Assuntos
Divisão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Interleucina-3/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Arteriosclerose/patologia , Northern Blotting , Células Cultivadas , DNA/biossíntese , DNA/efeitos dos fármacos , Fatores de Crescimento Endotelial/genética , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Expressão Gênica , Humanos , Immunoblotting , Interleucina-3/genética , Linfócitos/citologia , Linfócitos/metabolismo , Linfocinas/genética , Proteína Quinase 1 Ativada por Mitógeno/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Interleucina-3/genética , Receptores de Interleucina-3/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
11.
EDTNA ERCA J ; 25(2): 36-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10531881

RESUMO

In order to support interested colleagues with the concepts of Continuous Quality Improvement (CQI) and Clinical Standards for Nephrology Practice, a package of education support has been set up. We enhance the use of procedures, protocols, working plans, guidelines and nursing care plans as instruments of organisational integration. For the nursing care of renal patients in HD and PD we believe that all the procedures and protocols (P&P) above could have an important impact in the renal nursing practice. We propose that group members run a programme which is presented and implemented as a modular package including, theoretical knowledge, setting up working groups involved in literature revision, evaluation of defined P&P after a period of implementation, final implementation & periodic evaluation.


Assuntos
Avaliação em Enfermagem/normas , Diálise Renal/enfermagem , Insuficiência Renal/enfermagem , Gestão da Qualidade Total/métodos , Humanos , Diálise Renal/normas , Insuficiência Renal/terapia
12.
J Nephrol ; 12(5): 322-7, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10630697

RESUMO

The Italian Branch of EDTNA-ERCA organised a retrospective epidemiological investigation on the spread of HCV infection in dialysis. A questionnaire was sent to 830 Italian dialysis centres to collect information about prevalence and incidence of HCV infection among patients and staff, anti-HCV testing, presumed sources of infection, sanitation procedures and dialysis strategies adopted to prevent or reduce the transmission of HCV infection. Twenty-seven percent of the dialysis centres responded to the questionnaire. The answers confirmed the decline in HCV prevalence and incidence. At variance with official health organisation recommendations, isolation of anti-HCV-positive patients is still used in many centres (25%) despite the fact that it is not advisable in view of the high cost and uncertain benefit. Dedicated machines for anti-HCV-positive patients should be adopted, at least in units with a high prevalence of these cases.


Assuntos
Hepatite C/epidemiologia , Falência Renal Crônica/terapia , Diálise Peritoneal , Diálise Renal , Unidades Hospitalares de Hemodiálise/estatística & dados numéricos , Hepatite C/transmissão , Humanos , Incidência , Itália/epidemiologia , Falência Renal Crônica/virologia , Diálise Peritoneal/estatística & dados numéricos , Prevalência , Diálise Renal/estatística & dados numéricos , Estudos Retrospectivos , Precauções Universais
13.
EDTNA ERCA J ; 25(3): 38-42, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10786494

RESUMO

The Italian Branch of EDTNA/ERCA organised a national, epidemiological, retrospective study to collect data and implement preventative measures for the spread of HCV infection in dialysis units. A questionnaire was sent to staff in 830 dialysis centres to collect information relating to 1996. Data are presented on incidence/prevalence of HCV infection, antibodies, viraemia and mortality, and comparison of the management of HCV between centres. At variance with the recommendations of the Official Health Organisations, dedicated machines and separate rooms are used in many centres and this paper concludes with recommendations for units, in particular those units with a low prevalence of anti HCV positive patients.


Assuntos
Infecção Hospitalar/epidemiologia , Infecção Hospitalar/etiologia , Hepatite C/epidemiologia , Hepatite C/etiologia , Controle de Infecções/métodos , Falência Renal Crônica/terapia , Diálise Renal/efeitos adversos , Infecção Hospitalar/prevenção & controle , Hepatite C/prevenção & controle , Humanos , Incidência , Itália/epidemiologia , Avaliação das Necessidades , Vigilância da População , Prevalência , Inquéritos e Questionários
14.
Minerva Anestesiol ; 59(5): 223-7, 1993 May.
Artigo em Italiano | MEDLINE | ID: mdl-8355862

RESUMO

The inclusion of charcoal filters in anaesthetic low-flow systems contributes to the acceleration of the kinetics of isoflurane (Forane). In twenty subjects, scheduled for extra- and intracranial surgery, ventilated with a low-flow system (Ohmeda Excel OAV7750 with rebreathing cassette) with a mean total flow of 0.7 l/min, awakening was complete within 5 minutes from stopping isoflurane and including charcoal in the circuit. At the awakening, the expiratory concentration of isoflurane was 0.23% (95% confidence intervals: 0.19-0.27%): these values are similar to those of MACawake of isoflurane after fast alveolar washout. The use of charcoal during low-flow anaesthesia makes low-flow systems more flexible in their use; the anaesthetic level is more easily controllable and accidental overdosing of volatile anaesthetics can be immediately removed.


Assuntos
Anestesia por Inalação/instrumentação , Carvão Vegetal , Isoflurano/farmacocinética , Adulto , Idoso , Anestesia por Inalação/métodos , Feminino , Filtração , Humanos , Masculino , Pessoa de Meia-Idade , Alvéolos Pulmonares
16.
Minerva Urol Nefrol ; 44(1): 69-73, 1992.
Artigo em Italiano | MEDLINE | ID: mdl-1529401

RESUMO

The Authors report the arterial complications observed in a 360 kidney transplantations experience. They analyze the etiological, diagnostic and therapeutic features.


Assuntos
Transplante de Rim/efeitos adversos , Obstrução da Artéria Renal/etiologia , Hemorragia/etiologia , Humanos , Nefropatias/etiologia , Trombose/etiologia
17.
Minerva Urol Nefrol ; 44(1): 75-8, 1992.
Artigo em Italiano | MEDLINE | ID: mdl-1529402

RESUMO

The Authors report three cases of renal vein thrombosis after transplantation. One of these cases has been successfully admitted to surgical treatment. They point out the pathogenetical features and underline the importance of surgery.


Assuntos
Transplante de Rim/efeitos adversos , Veias Renais , Trombose/etiologia , Humanos , Trombose/cirurgia
18.
Minerva Cardioangiol ; 38(9): 397-400, 1990 Sep.
Artigo em Italiano | MEDLINE | ID: mdl-2084581

RESUMO

The Authors report their fifteen years experience, point out the clinical features of inflammatory abdominal aortic aneurysms and examine the different pathogenetic theories.


Assuntos
Aneurisma Aórtico/cirurgia , Aortite/cirurgia , Adulto , Idoso , Aorta Abdominal , Aneurisma Aórtico/complicações , Aortite/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Minerva Cardioangiol ; 38(5): 211-3, 1990 May.
Artigo em Italiano | MEDLINE | ID: mdl-2234452

RESUMO

Our experience with patients undergoing carotid endoarteriectomy over a 10 year period has been retrospectively reviewed. Nerve injuries were detected by reviewing postoperative progress and clinical notes. One hundred thirty-four procedures were performed on 120 patients, to 15 of whom (9%) occurred major nerve injuries. These included seven vagal nerve injuries causing ipsilateral vocal cord paralysis and hoarseness, five injuries of the marginal mandibular nerve and three injuries of the hypoglossal nerve. None of the patients with nerve injury had a stroke as a result of carotid operation. Vocal cord paralysis was documented by laryngoscopy. The incidence of cranial nerve injury during carotid endoarteriectomy appears to be higher than expected, particularly if asymptomatic patients are controlled.


Assuntos
Artérias Carótidas/cirurgia , Endarterectomia/efeitos adversos , Complicações Intraoperatórias/etiologia , Traumatismos dos Nervos Periféricos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino
20.
Minerva Cardioangiol ; 38(5): 215-7, 1990 May.
Artigo em Italiano | MEDLINE | ID: mdl-2234453

RESUMO

The results of 112 femoral embolectomies performed on 100 patients were reviewed. Operative mortality rate was 15% and early amputation (within 30 day-after the procedure) 18%. The role of early amputation was closely related to the time of leg ischemia. Current follow-up as established for 86 patients. 5 years and 10 years survival rates for the group were 49% and 40%. Although early survival is decreased after femoral embolectomy long term survivors can be expected to live independently with excellent limb salvage and function.


Assuntos
Embolia/cirurgia , Artéria Femoral/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA