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1.
Avian Dis ; 66(4): 410-417, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36715472

RESUMO

The ban of effective feed additives and therapeutics in the European Union and in other parts of the world led to a dramatic increase of histomonosis in turkeys. Despite the impact of the disease on the health and welfare of poultry, many questions remain open regarding the epidemiology of the pathogen. In this study, we retrospectively monitored a farm with recurring cases of histomonosis to identify possible routes of pathogen introduction and predisposing factors that may influence the disease development. We included 32 consecutive turkey flocks, which were fattened between 2007 and 2021 on the same farm under the same management and housing conditions. During this period, Histomonas meleagridis was detected in eight flocks of toms and four flocks of hens with a high variability in disease development. Outbreaks in toms led to significantly (P ≤ 0.05) higher mortality rates (5.3%-98.3%) than in hens (2.6%-6.1%). Most of the outbreaks (9/12) were diagnosed between June and September with a peak in August, suggesting a possible impact of higher temperatures either on the host or on the pathogen and pathogen-transmitting vectors. Further investigation is necessary to determine why hens might cope better with histomonosis than toms. Continuous flock and hygiene management is important to prevent an introduction of the causative pathogen and to control potential vectors.


Investigaciones retrospectivas de histomoniasis recurrente en una granja de pavos. La prohibición de aditivos alimentarios y productos terapéuticos efectivos en la Unión Europea y en otras partes del mundo condujo a un aumento dramático de histomoniasis en pavos. A pesar del impacto de la enfermedad en la salud y el bienestar de las aves, quedan muchas interrogantes abiertas con respecto a la epidemiología del patógeno. En este estudio, se monitoreó retrospectivamente una granja con casos recurrentes de histomoniasis para identificar posibles rutas de introducción de patógenos y factores predisponentes que puedan influir en el desarrollo de la enfermedad. Se incluyeron 32 lotes de pavos consecutivos, que fueron engordados entre 2007 y 2021 en la misma granja bajo las mismas condiciones de manejo y alojamiento. Durante este período, se detectó Histomonas meleagridis en ocho parvadas de machos y cuatro parvadas de gallinas con una alta variabilidad en el desarrollo de la enfermedad. Los brotes en machos llevaron a tasas de mortalidad significativamente más altas (P ≤ 0.05) (5.3 %­ - 98.3 %) que en gallinas (2.6 %­ - 6.1 %). La mayoría de los brotes (9/12) se diagnosticaron entre junio y septiembre con un pico en agosto, lo que sugiere un posible impacto de las temperaturas más altas sobre el huésped o en el patógeno y los vectores transmisores del patógeno. Se necesita más investigación para determinar por qué las gallinas pueden sobrellevar mejor la histomoniasis que los machos. El manejo continuo de la parvada y la higiene es importante para prevenir la introducción del patógeno causante y controlar a los vectores potenciales.


Assuntos
Doenças das Aves Domésticas , Infecções Protozoárias em Animais , Infecções por Protozoários , Animais , Feminino , Perus , Estudos Retrospectivos , Galinhas , Fazendas , Doenças das Aves Domésticas/prevenção & controle , Infecções por Protozoários/epidemiologia , Causalidade
2.
J Behav Med ; 41(4): 528-536, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29589257

RESUMO

We aimed to further the understanding of the low rates of sun protection in young women at risk for skin cancer. Six-hundred-sixty-one daily diary entries were received via text message over 14 days from 56 young women at moderate to high risk of developing skin cancer. Women reported whether or not they used sun protection and also listed what their reasons were for using protection or not using sun protection each day. Multi-level modeling was used to examine the influence of study variables when predicting daily sun protection or lack of protection. The number of days in which sun protection was reported was positively associated with "habit" and "prevention" as reasons for protection and negatively associated with "not-needed" and "unprepared" as reasons for non-protection. Self-reported sun protection increased over the 14-day study period. Results of this study suggest the potential value of interventions aimed at motives for sun-protection behaviors.


Assuntos
Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Neoplasias Cutâneas/prevenção & controle , Queimadura Solar/prevenção & controle , Protetores Solares/uso terapêutico , Adolescente , Adulto , Feminino , Humanos , Envio de Mensagens de Texto , Adulto Jovem
3.
Anaesthesia ; 72(2): 233-247, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27996086

RESUMO

Despite current recommendations on the management of pre-operative anaemia, there is no pragmatic guidance for the diagnosis and management of anaemia and iron deficiency in surgical patients. A number of experienced researchers and clinicians took part in an expert workshop and developed the following consensus statement. After presentation of our own research data and local policies and procedures, appropriate relevant literature was reviewed and discussed. We developed a series of best-practice and evidence-based statements to advise on patient care with respect to anaemia and iron deficiency in the peri-operative period. These statements include: a diagnostic approach for anaemia and iron deficiency in surgical patients; identification of patients appropriate for treatment; and advice on practical management and follow-up. We urge anaesthetists and peri-operative physicians to embrace these recommendations, and hospital administrators to enable implementation of these concepts by allocating adequate resources.


Assuntos
Anemia/terapia , Consenso , Deficiências de Ferro , Assistência Perioperatória , Custos de Cuidados de Saúde , Humanos , Injeções Intravenosas , Ferro/administração & dosagem
4.
Br J Anaesth ; 116(5): 723-4, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27106985
5.
Br J Anaesth ; 115(1): 15-24, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26089443

RESUMO

In major surgery, the implementation of multidisciplinary, multimodal and individualized strategies, collectively termed Patient Blood Management, aims to identify modifiable risks and optimise patients' own physiology with the ultimate goal of improving outcomes. Among the various strategies utilized in Patient Blood Management, timely detection and management of preoperative anaemia is most important, as it is in itself a risk factor for worse clinical outcome, but also one of the strongest predisposing factors for perioperative allogeneic blood transfusion, which in turn increases postoperative morbidity, mortality and costs. However, preoperative anaemia is still frequently ignored, with indiscriminate allogeneic blood transfusion used as a 'quick fix'. Consistent with reported evidence from other medical specialties, this imprudent practice continues to be endorsed by non-evidence based misconceptions, which constitute serious barriers for a wider implementation of preoperative haemoglobin optimisation. We have reviewed a number of these misconceptions, which we unanimously consider should be promptly abandoned by health care providers and replaced by evidence-based strategies such as detection, diagnosis and proper treatment of preoperative anaemia. We believe that this approach to preoperative anaemia management may be a viable, cost-effective strategy that is beneficial both for patients, with improved clinical outcomes, and for health systems, with more efficient use of finite health care resources.


Assuntos
Anemia/diagnóstico , Anemia/terapia , Hemoglobinas/análise , Cuidados Pré-Operatórios , Procedimentos Cirúrgicos Operatórios , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Transfusão de Sangue/estatística & dados numéricos , Feminino , Humanos , Masculino , Fatores de Risco
6.
Clin Nucl Med ; 40(5): e271-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25642915

RESUMO

The overexpression of somatostatin receptors on the tumor cell surface of neuroendocrine tumors (NETs) detected by multimodal functional imaging modalities such as SPECT and PET tracers constitutes a therapeutic option using targeting radiolabeled compounds. We will introduce the theranostic concept in general, explain in more detail its development in NETs, and discuss available SPECT and PET tracers regarding their potential for diagnostic imaging, visualization of target expression, and treatment tailoring. Moreover, we will discuss the currently available peptide receptor radionuclide therapy principles and compare them to previously published studies. Finally, we will discuss which new concepts will most likely influence the theranostic treatment approach in NETs in the future.


Assuntos
Tumores Neuroendócrinos/diagnóstico por imagem , Medicina de Precisão/métodos , Compostos Radiofarmacêuticos/uso terapêutico , Tomografia Computadorizada de Emissão de Fóton Único , Humanos , Tumores Neuroendócrinos/radioterapia
7.
Nuklearmedizin ; 53(2): 19-25, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24473996

RESUMO

AIM: To elucidate techniques most commonly used for interpreting oncologic PET/CT studies. This survey forms a basis to work on standardization of reporting and highlight the most important issues to be addressed. METHODS: A web-based survey of 329 PET/CT imaging specialists was designed with the intent to determine image interpretation patterns. The questionnaire consisted of 19 questions. Of the 329 participants, 230 were nuclear medicine specialists, 46 were radiologists, and 53 had dual-board certification. RESULTS: Report ofstandardized uptake values (SUV) is not consistent;only50.2% of respondents always report SUVs, while 45.2% report only if needed or requested. 80.9% of respondents indicated that reporting of SUV is only appropriate when its limitations are understood whereby a large majority prefer to report SUVmax. Maximum intensity projection (MIP) images are almost always reviewed by 91.1% of the respondents. An accurate and detailed clinical history is considered an essential element for reading PET/CT studies by 84.0%, but only 20.7% report that this is always available. The most common self-reported average time for reviewing and reporting of whole body PET/CT (with no prior comparison scan) was 15-20 min (27.5%). CONCLUSION: PET readers have considerable reservations regarding the use and reporting of SUVs. SUVmax is more frequently used than SUVmean. Evaluation of MIP images is considered an important element of PET/CT interpretation. Although availability of sufficient patient's history is considered essential, this is rarely available.


Assuntos
Registros Eletrônicos de Saúde/estatística & dados numéricos , Imagem Multimodal/estatística & dados numéricos , Neoplasias/diagnóstico , Tomografia por Emissão de Pósitrons/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Sistemas de Informação em Radiologia/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Registros Eletrônicos de Saúde/classificação , Pesquisas sobre Atenção à Saúde , Registros de Saúde Pessoal , Humanos , Internacionalidade
8.
Am J Transplant ; 9(2): 428-32, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19178417

RESUMO

Posttransplant malignancy developing in an allograft is an uncommon complication of organ transplantation. The tumor may represent malignant transformation of donor or recipient cells that were previously normal, metastatic malignancy of recipient origin or malignancy transmitted from organ donor to recipient. Establishing the origin of the malignancy is critical to treatment algorithms. It is generally believed allograft removal and immunosuppression withdrawal will lead to resolution of transmitted malignancies in cases where the renal allograft is the origin. We report a male patient who developed metastatic ovarian malignancy secondary to donor transmission.


Assuntos
Adenocarcinoma Mucinoso/etiologia , Neoplasias Renais/etiologia , Transplante de Rim/efeitos adversos , Neoplasias Ovarianas/etiologia , Doadores de Tecidos , Adenocarcinoma Mucinoso/secundário , Adulto , Evolução Fatal , Feminino , Humanos , Neoplasias Renais/secundário , Neoplasias Hepáticas/secundário , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Nefrectomia , Neoplasias Ovarianas/patologia , Tomografia Computadorizada por Raios X
9.
Kidney Int ; 73(5): 528-30, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18274543

RESUMO

Serious adverse events that occur with the administration of iron dextran are due to the high molecular weight preparations. Conclusions that iron sucrose and ferric gluconate are safer than iron dextran may be premature. Published literature comparing safety profiles of available parenteral iron products is reviewed. Administration of iron salts to pre-dialysis patients with chronic kidney disease may not be optimal. We recommend the total dose infusion of low molecular weight iron dextran as an option for iron replacement.


Assuntos
Compostos Férricos/efeitos adversos , Hematínicos/efeitos adversos , Complexo Ferro-Dextran/efeitos adversos , Nefropatias/tratamento farmacológico , Doença Crônica , Compostos Férricos/administração & dosagem , Óxido de Ferro Sacarado , Ácido Glucárico , Hematínicos/administração & dosagem , Humanos , Infusões Parenterais , Complexo Ferro-Dextran/administração & dosagem
10.
Clin Anat ; 20(8): 933-42, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17879305

RESUMO

Our aims were (1) by computed tomography (CT) to establish a population database for pancreas volume (parenchyma and fat) from birth to age 100 years, (2) in adults, to establish the impact of gender, obesity, and the presence or absence of type-2 diabetes on pancreatic volume (parenchyma and fat), and (3) to confirm the latter histologically from pancreatic tissue obtained at autopsy with a particular emphasis on whether pancreatic fat is increased in type-2 diabetes. We measured pancreas volume in 135 children and 1,886 adults (1,721 nondiabetic and 165 with type-2 diabetes) with no history of pancreas disease who had undergone abdominal CT scan between 2003 and 2006. Pancreas volume was computed from the contour of the pancreas on each CT image. In addition to total pancreas volume, parenchymal volume, fat volume, and fat/parenchyma ratio (F/P ratio) were determined by CT density. We also quantified pancreatic fat in autopsy tissue of 47 adults (24 nondiabetic and 23 with type-2 diabetes). During childhood and adolescence, the volumes of total pancreas, pancreatic parenchyma, and fat increase linearly with age. From age 20-60 years, pancreas volume reaches a plateau (72.4 +/- 25.8 cm(3) total; 44.5 +/- 16.5 cm(3) parenchyma) and then declines thereafter. In adults, total ( approximately 32%), parenchymal ( approximately 13%), and fat ( approximately 68%) volumes increase with obesity. Pancreatic fat content also increases with aging but is not further increased in type-2 diabetes. We provide lifelong population data for total pancreatic, parenchymal, and fat volumes in humans. Although pancreatic fat increases with aging and obesity, it is not increased in type-2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Obesidade/fisiopatologia , Pâncreas/anatomia & histologia , Caracteres Sexuais , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Autopsia , Índice de Massa Corporal , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Imagens de Fantasmas , Magreza/fisiopatologia , Tomografia Computadorizada por Raios X
11.
Parkinsonism Relat Disord ; 13(6): 359-61, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17055324

RESUMO

The purpose of this study was to assess the genotype-phenotype of PINK1 mutations. We genotyped eight known mutations in three clinic-based cohorts with Parkinsonism and found one homozygous p.L347P mutation in PINK1. Clinically, hypo-osmia and profound diurnal variation of symptoms were identified as novel features; fluorodopa positron emission tomography revealed striking decline in striatal fluorodopa uptake. We suggest that it may be possible to clinically separate this form of Parkinsonism from dopa-responsive dystonia and Parkin-related Parkinsonism. Furthermore, as this mutation has only been reported in Filipinos (two originated from Luzon island), our results support the hypothesis of a common founder.


Assuntos
Lisina/genética , Mutação , Doença de Parkinson/genética , Prolina/genética , Proteínas Quinases/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Análise Mutacional de DNA , Feminino , Frequência do Gene , Predisposição Genética para Doença , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade
12.
Mol Imaging Biol ; 7(5): 369-76, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16220355

RESUMO

PURPOSE: This study was conducted to compare the clinical stage derived from 2-deoxy-2-[F-18]fluoro-D-glucose (FDG) positron emission tomography (PET) to that of integrated PET/computed tomography (CT) in restaged breast cancer patients. PROCEDURES: Fifty-eight female patients (age range 29-80 years, mean age +/-SD, 53.3 +/- 11.7 years) underwent PET/CT restaging for breast cancer. Two experienced nuclear medicine physicians interpreted PET images. A radiologist was added for reading PET/CT studies. A patient-based analysis was performed. Histopathological findings, correlative imaging studies, changes in number, size, and hypermetabolic activity of suspicious lesions and/or patient outcome served as standard of reference for determining the diagnostic accuracy of both modalities. RESULTS: PET staged 79.3% (46/58) of the patients correctly, overstaged seven (12.1%), and understaged five patients (8.6%). Integrated PET/CT staged 89.7% (52/58) of the patients correctly, overstaged four (6.9%), and understaged two patients (3.4%). The staging accuracy of PET/CT was not significantly better than that of PET alone (p = 0.059). Lesions exhibiting mild hypermetabolic activity, benign inflammatory lesions, and physiological variants largely explained incorrect PET findings. CONCLUSION: Integrated PET/CT only marginally improves the restaging accuracy over PET alone (p = 0.059) in breast cancer patients.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica/diagnóstico por imagem , Metástase Neoplásica/patologia , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons/normas , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
13.
Nuklearmedizin ; 44 Suppl 1: S18-23, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16395974

RESUMO

PET/CT is now established as the most important imaging tool in oncology. PET/CT stages and restages cancer with a higher accuracy than PET or CT alone. The sometimes irrational approach to combine state of the art PET with the highest end CT devices should give way to a more reasonable equipment design tailored towards the specific clinical indications in well-defined patient populations. The continuing success of molecular PET/CT now depends more upon advances in molecular imaging with the introduction of targeted imaging probes for individualized therapy approaches in cancer patients and less upon technological advances of imaging equipment.


Assuntos
Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/normas , Tomografia Computadorizada por Raios X/normas , Feminino , Humanos , Estadiamento de Neoplasias , Neoplasias/patologia , Tomografia por Emissão de Pósitrons/tendências , Reprodutibilidade dos Testes , Software , Tomografia Computadorizada por Raios X/tendências
14.
Food Chem Toxicol ; 42(9): 1531-42, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15234083

RESUMO

Polydextrose is a non-digestible 1 kcal/g polysaccharide used primarily as a sugar replacer and dietary fiber in foods. At typical use levels, polydextrose provides physiological effects similar to those of other dietary fibers. However, excessive consumption of non-digestible carbohydrates can lead to gastrointestinal distress. Nine clinical studies were conducted with polydextrose to evaluate the extent of such symptoms. These studies determined laxation endpoints in adults and children, and showed that polydextrose was better tolerated than most other low digestible carbohydrates (e.g. polyols). This is because of a higher molecular weight and partial colonic fermentation, leading to a lower risk of osmotic diarrhea. After evaluating these studies, the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and the European Commission Scientific Committee for Food (EC/SCF) concluded that polydextrose has a mean laxative threshold of approximately 90 g/d (1.3 g/kg bw) or 50 g as a single dose.


Assuntos
Carboidratos da Dieta/efeitos adversos , Fibras na Dieta/efeitos adversos , Aditivos Alimentares/efeitos adversos , Gastroenteropatias/etiologia , Glucanos/efeitos adversos , Catárticos , Humanos
15.
Opt Express ; 12(19): 4443-8, 2004 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-19483994

RESUMO

We demonstrate a new scheme for the efficient suppression of Brillouin scattering of a single-frequency laser source in a 72 m-long Neodymium-doped fiber amplifier by simultaneous amplification of two seed lasers separated in wavelength by two times the Brillouin-shift. This scheme can be independently employed in addition to conventional methods of suppressing stimulated Brillouin scattering enabling further power scaling of existing systems.

16.
Opt Lett ; 28(22): 2222-4, 2003 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-14649948

RESUMO

We report on what is to our knowledge the first optical parametric oscillator (OPO) pumped by microsecond pulses from a wavelength-tunable solid-state laser. The singly resonant OPO (SRO) is based on a periodically poled LiNbO3 crystal and pumped with 2.1-micros-long pulses from an actively Q-switched Yb fiber laser. At an average fiber laser power of 3.6 W, the SRO generates 1.9-micros-long pulses with a repetition rate of 25 kHz and an average power of 560 mW at 3360 nm. The SRO was tuned from 1518 to 1634 nm (signal) and from 3145 to 3689 nm (idler) via the crystal temperature and poling period. By all-electronic tuning of the fiber laser wavelength over 19 nm, tuning of the mid-infrared idler wavelength over 195 nm was achieved.

17.
Opt Lett ; 28(11): 920-2, 2003 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12816246

RESUMO

We report on rapid, all-electronically controlled wavelength tuning of a continuous-wave (cw) optical parametric oscillator (OPO) pumped by an ytterbium fiber laser. The OPO is singly resonant for the signal wave and consists of a 40-mm-long periodically poled lithium niobate crystal in a four-mirror ring cavity. By tuning of the fiber-laser wavelength over 33 nm through an intracavity acousto-optic tunable filter, the OPO idler wavelength is tuned from 3160 to 3500 nm in 330 micros, corresponding to an idler frequency-tuning speed of 28 THz/ms. At a fiber-laser power of 6.6 W at 1074 nm, the singly resonant OPO generates 1.13-W cw idler radiation at 3200 nm.

18.
Opt Express ; 11(21): 2730-5, 2003 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-19471387

RESUMO

Q-switching of a wavelength tunable Yb3+-doped double-clad fiber laser by a Tm3+-codoping in the gain fiber is demonstrated. This system showed up to 2.4 W output power, up to 140 kHz repetition rate, a maximum pulse energy of 21.8 microJ and a minimum pulse duration of 1.1 micros. Using a grating pair in Littrow-Littman configuration the emission wavelength was tunable between 1055 nm and 1090 nm. The output radiation showed a maximum spectral linewidth of 4 GHz.

19.
Minerva Pediatr ; 54(1): 25-39, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11862164

RESUMO

Adolescent morbidity and mortality are more often due to preventable causes and to risky behavioral choices than to "natural" causes, such as cardiovascular disease or cancer. The leading causes of death among adolescents in Western, industrialized nations are unintentional injuries, especially motor vehicle crashes, homicide, and suicide. The physical and cognitive development of adolescents also results in increased risky behavioral choices, and to high rates of sexually transmitted diseases, substance use and misuse, and inadequate nutrition. These lifestyle choices also have repercussions that last into adulthood. Brief counseling interventions by physicians or other clinicians have been shown to be effective in modifying health risk behaviors in adolescents. Adolescents also have indicated both a belief that physicians should counsel them on risk behaviors and a willingness to discuss risk behaviors if asked about them in a confidential manner. In this paper, we review the leading causes of adolescent morbidity and mortality in the United States and Western Europe, including injuries, violence, depression and suicide, substance use, sexual activity, and nutrition, physical activity, and eating disorders. In addition, we describe the effectiveness of physician counseling for reduction or prevention of specific risk behaviors and the importance of providing comprehensive, confidential care. Additionally, we describe the results of a recent study of implementation of Adolescent Preventive Service Guidelines in community and migrant health centers that increased risky behavior screening and counseling for adolescent patients seen for routine/well care visits.


Assuntos
Serviços de Saúde do Adolescente/normas , Nível de Saúde , Adolescente , Serviços de Saúde Comunitária/normas , Humanos , Serviços Preventivos de Saúde/normas , Assunção de Riscos , Infecções Sexualmente Transmissíveis/prevenção & controle , Transtornos Relacionados ao Uso de Substâncias , Tentativa de Suicídio/prevenção & controle , Violência/prevenção & controle , Ferimentos e Lesões/prevenção & controle
20.
Opt Lett ; 27(6): 418-20, 2002 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18007820

RESUMO

We report on what is to our knowledge the first continuous-wave (cw) optical parametric oscillator (OPO) that is pumped by a tunable fiber laser. The OPO is singly resonant for the signal wave and consists of a 40-mm-long periodically poled LiNbO(3) crystal in a four-mirror ring cavity. At a pump power of 8.3 W provided by the wavelength-tunable Yb-doped fiber laser, the singly resonant OPO generates 1.9 W of 3200-nm cw idler radiation. The singly resonant OPO was tuned from 1515 to 1633 nm (signal) and from 3057 to 3574 nm (idler) by means of the crystal temperature and poling period. We obtained a wide idler tuning range, from 2980 to 3700 mn, by tuning the wavelength of the fiber laser from 1032 to 1095 nm.

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