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1.
Sci Rep ; 6: 20644, 2016 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-26856886

RESUMO

We demonstrated a method to construct high efficiency saturable absorbers based on the evanescent light field interaction of CVD monolayer graphene deposited on side-polished D-shaped optical fiber. A set of samples was fabricated with two different core-graphene distances (0 and 1 µm), covered with graphene ranging between 10 and 25 mm length. The mode-locking was achieved and the best pulse duration was 256 fs, the shortest pulse reported in the literature with CVD monolayer graphene in EDFL. As result, we find a criterion between the polarization relative extinction ratio in the samples and the pulse duration, which relates the better mode-locking performance with the higher polarization extinction ratio of the samples. This criterion also provides a better understanding of the graphene distributed saturable absorbers and their reproducible performance as optoelectronic devices for optical applications.

2.
Neurology ; 67(10): 1786-91, 2006 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-17050822

RESUMO

OBJECTIVE: To evaluate the frequency of leucine-rich repeat kinase gene (LRRK2) mutations and single nucleotide polymorphisms (SNPs) in early-onset Parkinson disease (EOPD) and late-onset Parkinson disease (LOPD). METHODS: We genotyped five previously reported LRRK2 mutations (G2019S, L1114L, I1122V, R1441C, and Y1699C) and 17 coding SNPs for haplotype analysis in 504 cases with PD and 314 controls enrolled in the Genetic Epidemiology of PD Study. Cases and controls were recruited without knowledge of family history of PD and cases were oversampled in the < or =50 age at onset (AAO) category. RESULTS: The LRRK2 G2019S mutation was present in 28 cases with PD (5.6%) and two controls (0.6%) (chi(2) = 13.25; p < 0.01; odds ratio 9.18, 95% CI: 2.17 to 38.8). The mutations L1114L, I1122V, R1441C, and Y1699C were not identified. The frequency of the LRRK2 G2019S mutation was 4.9% in 245 cases with AAO < or =50 years vs 6.2% in 259 cases with AAO >50 (p = 0.56). All cases with PD with the G2019S mutation shared the same disease-associated haplotype. The frequency of the LRRK2 G2019S mutation was higher in the subset of 181 cases reporting four Jewish grandparents (9.9%) than in other cases (3.1%) (p < 0.01). Age-specific penetrance to age 80 was 24% and was similar in Jewish and non-Jewish cases. CONCLUSIONS: The G2019S mutation is a risk factor in both early- and late-onset Parkinson disease and confirms the previous report of a greater frequency of the G2019S mutation in Jewish than in non-Jewish cases with Parkinson disease.


Assuntos
Predisposição Genética para Doença/genética , Mutação/genética , Doença de Parkinson/etnologia , Doença de Parkinson/genética , Proteínas Serina-Treonina Quinases/genética , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , Feminino , Frequência do Gene/genética , Testes Genéticos , Genótipo , Haplótipos/genética , Heterozigoto , Humanos , Padrões de Herança/genética , Judeus/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/metabolismo , Penetrância , Polimorfismo de Nucleotídeo Único/genética
4.
Environ Manage ; 27(4): 609-26, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11289458

RESUMO

We estimated the effects of a temperature control device (TCD) on a suite of thermodynamic and limnological attributes for a large storage reservoir, Shasta Lake, in northern California. Shasta Dam was constructed in 1945 with a fixed-elevation penstock. The TCD was installed in 1997 to improve downstream temperatures for endangered salmonids by releasing epilimnetic waters in the winter/spring and hypolimnetic waters in the summer/fall. We calibrated a two-dimensional hydrodynamic reservoir water quality model, CE-QUAL-W2, and applied a structured design-of-experiment simulation procedure to predict the principal limnological effects of the TCD under a variety of environmental scenarios. Calibration goodness-of-fit ranged from good to poor depending on the constituent simulated, with an R2 of 0.9 for water temperature but 0.3 for phytoplankton. Although the chemical and thermal characteristics of the discharge changed markedly, the reservoir's characteristics remained relatively unchanged. Simulations showed the TCD causing an earlier onset and shorter duration of summer stratification, but no dramatic affect on Shasta's nutrient composition. Peak inreservoir phytoplankton production may begin earlier and be stronger in the fall with the TCD, while outfall phytoplankton concentrations may be much greater in the spring. Many model predictions differed from our a priori expectations that had been shaped by an intensive, but limited-duration, data collection effort. Hydrologic and meteorological variables, most notably reservoir carryover storage at the beginning of the calendar year, influenced model predictions much more strongly than the TCD. Model results indicate that greater control over reservoir limnology and release quality may be gained by carefully managing reservoir volume through the year than with the TCD alone.


Assuntos
Modelos Teóricos , Fitoplâncton , Temperatura , Poluentes da Água/análise , Clima , Ecossistema , Dinâmica Populacional , Estações do Ano
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