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1.
Opt Lett ; 46(15): 3504-3507, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34329210

RESUMO

This Letter, to the best of our knowledge, reports mid-infrared fiber lasing beyond 5 µm at room temperature for the first time, Ce3+-doped, chalcogenide glass, step index fiber employed in-band pumping with a 4.15 µm quantum cascade laser. The lasing fiber is was 64 mm long, with a calculated numerical aperture of 0.48 at the lasing wavelengths. The core glass was Ge15As21Ga1Se63 atomic % (at. %), doped with 500 parts-per-million-by-weight Ce, with a 9 µm core diameter. The cladding glass was Ge21Sb10Se69 at. % with a 190 µm outer diameter. As pump power increases continuous wave lasing corresponding to the 2F7/2→2F5/2, transition in the Ce3+ ion occurs at 5.14 µm, 5.17 µm, and 5.28 µm.

2.
Opt Express ; 26(18): 23641-23660, 2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-30184863

RESUMO

We propose a model for resonantly pumped Pr3+-doped chalcogenide fiber amplifiers, which includes excited state absorption and the full spectral amplified spontaneous emission spanning from 2 µm to 6 µm. Based on this model, the observed near- and mid-infrared photoluminescence generated from Pr3+-doped chalcogenide fiber is explained. Then the output properties of a 4.1 µm resonantly pumped Pr3+-doped chalcogenide fiber amplifier are simulated in both co- and counter-pumping schemes. Results show that the 4.1 µm counter-pumped fiber amplifier can achieve a power conversion efficiency (PCE) of over 62.8% for signal wavelengths ranging from 4.5 µm to 5.3 µm. This is, to our best knowledge, the highest simulated PCE for a Pr3+-doped chalcogenide fiber amplifier.

3.
Rozhl Chir ; 96(7): 276-283, 2017.
Artigo em Tcheco | MEDLINE | ID: mdl-28948797

RESUMO

This article deals with a surgical approach to primary gastrointestinal lymphoma - a rare finding when compared to primary gastric carcinoma. The clinical findings, diagnosis and staging of the disease as well as various treatment methods and prognosis of the condition are discussed. As it is evident from the paper, the opinions of individual authors regarding this diagnosis may often differ considerably. Furthermore, this paper presents two separate case studies of surgical treatment for gastric lymphomas performed at our department in 2016. Case study 1 describes a surgical intervention for acute abdomen, where lymphoma was already diagnosed peroperatively. Case study 2 presents the case of a patient indicated for elective laparoscopic cholecystectomy with an unexpected finding of primary gallbladder lymphoma.Key words: primary gastrointestinal lymphoma - chemotherapy - surgical intervention - primary intestinal lymphoma - primary lymphoma of the gallbladder.


Assuntos
Neoplasias da Vesícula Biliar , Neoplasias Gastrointestinais , Linfoma , Colecistectomia Laparoscópica , Neoplasias da Vesícula Biliar/diagnóstico , Neoplasias da Vesícula Biliar/cirurgia , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/cirurgia , Humanos , Linfoma/diagnóstico , Linfoma/cirurgia
4.
Rozhl Chir ; 95(9): 373-376, 2016.
Artigo em Tcheco | MEDLINE | ID: mdl-27653307

RESUMO

Our case study presents a case of foreign body migration through the vascular system of the human body. The following paper is a comprehensive overview of different diagnostic approaches, extraction indications, common ways in which a foreign body can migrate via the vascular system and possible complications caused by the migration or extraction of the foreign body.


Assuntos
Migração de Corpo Estranho/diagnóstico , Migração de Corpo Estranho/terapia , Artéria Pulmonar , Seguimentos , Migração de Corpo Estranho/complicações , Humanos , Tomografia Computadorizada por Raios X
5.
Opt Express ; 22(18): 21236-52, 2014 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-25321504

RESUMO

The photoluminescent-(PL)-properties of Pr³âº-ions in indium-containing selenide-chalcogenide bulk-glasses are found to be superior when compared with gallium-containing analogues. We observe circa doubling of mid-infrared (MIR) PL intensity from 3.5 to 6 µm for bulk glasses, pumped at 1.55 µm wavelength, and an increased excited state lifetime at 4.7 µm. PL is reported in optically-clad fiber. Ga addition is well known to enhance RE³âº solubility and PL behavior, and is believed to form ([RE³âº]-Se-[Ga(III)]) in the glasses. Indium has the same outer electronic-structure as gallium for solvating the RE-ions. Moreover, indium is heavier and promotes lower phonon energy locally around the RE-ion, thereby enhancing the RE-ion PL behavior, as observed here.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Gálio/análise , Vidro/química , Índio/análise , Fibras Ópticas
6.
Sci Rep ; 10(1): 493, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949260

RESUMO

Interleukin 27 (IL-27), a member of the IL-12 family, is important for T cell differentiation; however, little is known about its effect on dendritic cells (DCs). IL-27 can activate multiple signaling cascades, including the JAK/STAT pathway, and depending on the setting it can both promote and antagonize inflammatory responses. An anti-inflammatory function of IL-27 has been reported in several autoimmune diseases; however, in type 1 diabetes (T1D), an autoimmune disease where autoreactive cytotoxic T cells attack insulin-producing beta cells, IL-27 has been shown to have a dual role and contradictory effects. Here, we show impaired IL-27 signaling in a large cohort of T1D patients (n = 51) compared to age- and gender-matched healthy donors. Increased expression of the IL-27 receptor subunit IL-27Ralpha mRNA in purified myeloid DCs (mDCs), detected by gene expression microarrays was mirrored by enhanced signal transduction in T1D mDCs in response to IL-27 stimulation. Higher STAT phosphorylation in T1D patients was also accompanied by elevated expression of the inhibitory molecules PD-L1, PD-L2 and PD-1, which may suggest not only immunomodulatory mechanisms of IL-27 in T1D but also a compensatory effort of T1D dendritic cells against the ongoing inflammation.


Assuntos
Antígeno B7-H1/genética , Diabetes Mellitus Tipo 1/metabolismo , Perfilação da Expressão Gênica/métodos , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Adulto , Idoso , Antígeno B7-H1/metabolismo , Estudos de Casos e Controles , Células Dendríticas/imunologia , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Feminino , Humanos , Interleucinas/genética , Interleucinas/metabolismo , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação , Receptores de Interleucina/genética , Receptores de Interleucina/metabolismo
7.
Opt Quantum Electron ; 47: 1389-1395, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27069300

RESUMO

We study the mechanism of the population inversion in mid-infrared fibre lasers based on a chalcogenide glass host doped with active lanthanide ions. Three lanthanide dopant ions are considered: terbium, dysprosium and praseodymium. We predict the relevant trivalent ion level populations and gain. The simulation parameters were obtained by fabricating and optically characterising a series of trivalent ion doped chalcogenide glass samples. We also provide simple analytical expressions that aid the design of the cascade lasing process.

8.
Pediatr Pol ; 71(2): 111-6, 1996 Feb.
Artigo em Polonês | MEDLINE | ID: mdl-8966075

RESUMO

We present the results of observation and treatment of 440 children aged 8-10 years coming from a region of heavy industrial pollution around Legnica. The majority of children from the investigated group presented signs of chronic inflammation of the upper airways (at the beginning of their stay in Rabka the entire group had an average 16.6 +/- 15.7 mm/1h ESR-Erythrocyte sedimentation rate and their whole-blood lead level ranged from 5 to 15 micrograms%, averaging was 9.1 +/- 2.7 micrograms%). At the beginning of their stay in Rabka, acute-phase proteins levels of the Legnica children were compared to those of children from health-resort region of Rabka and were found to differ significantly in respect to ferritin (p < 0.001) and transferrin (p < 0.01) serum levels. Treatment with propolis significantly modified the climatic effects on ESR, on some electrophoretical fractions of serum proteins and on some A-PhP involved in iron metabolism. There was no individual correlation between the whole blood lead level and acute-phase proteins levels and the intensity of their changes after treatment.


Assuntos
Proteínas de Fase Aguda/fisiologia , Poluição do Ar , Chumbo/sangue , Ceruloplasmina/análise , Criança , Ferritinas/sangue , Haptoglobinas/análise , Humanos , Saúde Ocupacional , Transferrina/análise
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