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2.
Sci Rep ; 11(1): 9370, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33931715

RESUMO

The [Formula: see text] and [Formula: see text] transitions in Li-like carbon ions stored and cooled at a velocity of [Formula: see text] in the experimental storage ring (ESR) at the GSI Helmholtz Centre in Darmstadt have been investigated in a laser spectroscopy experiment. Resonance wavelengths were obtained using a new continuous-wave UV laser system and a novel extreme UV (XUV) detection system to detect forward emitted fluorescence photons. The results obtained for the two transitions are compared to existing experimental and theoretical data. A discrepancy found in an earlier laser spectroscopy measurement at the ESR with results from plasma spectroscopy and interferometry has been resolved and agreement between experiment and theory is confirmed.

3.
J Evol Biol ; 30(2): 244-256, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27696584

RESUMO

Phenotypic traits such as ornaments and armaments are generally shaped by sexual selection, which often favours larger and more elaborate males compared to females. But can sexual selection also influence the brain? Previous studies in vertebrates report contradictory results with no consistent pattern between variation in brain structure and the strength of sexual selection. We hypothesize that sexual selection will act in a consistent way on two vertebrate brain regions that directly regulate sexual behaviour: the medial preoptic nucleus (MPON) and the ventromedial hypothalamic nucleus (VMN). The MPON regulates male reproductive behaviour whereas the VMN regulates female reproductive behaviour and is also involved in male aggression. To test our hypothesis, we used high-resolution magnetic resonance imaging combined with traditional histology of brains in 14 dragon lizard species of the genus Ctenophorus that vary in the strength of precopulatory sexual selection. Males belonging to species that experience greater sexual selection had a larger MPON and a smaller VMN. Conversely, females did not show any patterns of variation in these brain regions. As the volumes of both these regions also correlated with brain volume (BV) in our models, we tested whether they show the same pattern of evolution in response to changes in BV and found that the do. Therefore, we show that the primary brain nuclei underlying reproductive behaviour in vertebrates can evolve in a mosaic fashion, differently between males and females, likely in response to sexual selection, and that these same regions are simultaneously evolving in concert in relation to overall brain size.


Assuntos
Encéfalo/anatomia & histologia , Lagartos/anatomia & histologia , Preferência de Acasalamento Animal , Animais , Feminino , Masculino , Caracteres Sexuais , Comportamento Sexual , Comportamento Sexual Animal
4.
Mol Psychiatry ; 20(1): 2-17, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25349164

RESUMO

Due to their well-characterized neural development and high genetic homology to mammals, zebrafish (Danio rerio) have emerged as a powerful model organism in the field of biological psychiatry. Here, we discuss the molecular psychiatry of zebrafish, and its implications for translational neuroscience research and modeling central nervous system (CNS) disorders. In particular, we outline recent genetic and technological developments allowing for in vivo examinations, high-throughput screening and whole-brain analyses in larval and adult zebrafish. We also summarize the application of these molecular techniques to the understanding of neuropsychiatric disease, outlining the potential of zebrafish for modeling complex brain disorders, including attention-deficit/hyperactivity disorder (ADHD), aggression, post-traumatic stress and substance abuse. Critically evaluating the advantages and limitations of larval and adult fish tests, we suggest that zebrafish models become a rapidly emerging new field in modern molecular psychiatry research.


Assuntos
Doenças do Sistema Nervoso Central/patologia , Modelos Animais de Doenças , Transtornos Mentais/patologia , Pesquisa Translacional Biomédica , Animais , Doenças do Sistema Nervoso Central/genética , Transtornos Mentais/genética , Peixe-Zebra/genética
5.
Phys Rev Lett ; 109(20): 202506, 2012 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-23215479

RESUMO

The neutron capture cross section of (235)U was measured for the neutron incident energy region between 4 eV and 1 MeV at the DANCE facility at the Los Alamos Neutron Science Center with an unprecedented accuracy of 2-3% at 1 keV. The new methodology combined three independent measurements. In the main experiment, a thick actinide sample was used to determine neutron capture and neutron-induced fission rates simultaneously. In the second measurement, a fission tagging detector was used with a thin actinide sample and detailed characteristics of the prompt-fission gamma rays were obtained. In the third measurement, the neutron scattering background was characterized using a sample of (208)Pb. The relative capture cross section was obtained from the experiment with the thick (235)U sample using a ratio method after the subtraction of the fission and neutron scattering backgrounds. Our result indicates errors that are as large as 30% in the 0.5-2.5 keV region, in the current knowledge of neutron capture as embodied in major nuclear data evaluations. Future modifications of these databases using the improved precision data given herein will have significant impacts in neutronics calculations for a variety of nuclear technologies.

6.
Appl Radiat Isot ; 70(11): 2602-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22940414

RESUMO

Cross sections for (223,)(225)Ra, (225)Ac and (227)Th production by the proton bombardment of natural thorium targets were measured at proton energies below 200 MeV. Our measurements are in good agreement with previously published data and offer a complete excitation function for (223,)(225)Ra in the energy range above 90 MeV. Comparison of theoretical predictions with the experimental data shows reasonable-to-good agreement. Results indicate that accelerator-based production of (225)Ac and (223)Ra below 200 MeV is a viable production method.


Assuntos
Actínio , Rádio (Elemento) , Tório/efeitos da radiação , Actínio/química , Prótons , Rádio (Elemento)/química , Espectrometria gama
7.
Appl Radiat Isot ; 70(11): 2590-5, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22944532

RESUMO

Cross sections for the formation of (225,227)Ac, (223,225)Ra, and (227)Th via the proton bombardment of natural thorium targets were measured at a nominal proton energy of 800 MeV. No earlier experimental cross section data for the production of (223,225)Ra, (227)Ac and (227)Th by this method were found in the literature. A comparison of theoretical predictions with the experimental data shows agreement within a factor of two. Results indicate that accelerator-based production of (225)Ac and (223)Ra is a viable production method.


Assuntos
Actínio , Rádio (Elemento) , Tório/efeitos da radiação , Actínio/química , Braquiterapia , Prótons , Rádio (Elemento)/química
8.
Phys Rev Lett ; 108(14): 142502, 2012 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-22540788

RESUMO

We obtained the total radiation widths of s-wave resonances through an R-matrix analysis of (147)Sm(n,γ) cross sections. Distributions of these widths differ markedly for resonances below and above E(n)=300 eV, which is in stark contrast to long-established theory. We show that this change, as well as a similar change in the neutron-width distribution reported previously, is reflected in abrupt increases in both the average (147)Sm(n,γ) cross section and fluctuations about the average near 300 eV. Such effects could have important consequences for applications such as nuclear astrophysics and nuclear criticality safety.

9.
Blood ; 97(2): 388-92, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11154213

RESUMO

A retrospective study was performed to collect information regarding efficacy and toxicity of cidofovir (CDV) in allogeneic stem cell transplant patients. Data were available on 82 patients. The indications for therapy were cytomegalovirus (CMV) disease in 20 patients, primary preemptive therapy in 24 patients, and secondary preemptive therapy in 38 patients. Of the patients, 47 had received previous antiviral therapy with ganciclovir, foscarnet, or both drugs. The dosage of CDV was 1 to 5 mg/kg per week followed by maintenance every other week in some patients. The duration of therapy ranged from 1 to 134 days (median, 22 days). All patients received probenecid and prehydration. Ten of 20 (50%) patients who were treated for CMV disease (9 of 16 with pneumonia) responded to CDV therapy, as did 25 of 38 (66%) patients who had failed or relapsed after previous preemptive therapy and 15 of 24 (62%) patients in whom CDV was used as the primary preemptive therapy. Of the patients, 21 (25.6%) developed renal toxicity that remained after cessation of therapy in 12 patients. Fifteen patients developed other toxicities that were potentially due to CDV or the concomitantly given probenecid. No toxicity was seen in 45 (61.6%) patients. Cidofovir can be considered as second-line therapy in patients with CMV disease failing previous antiviral therapy. However, additional studies are needed before CDV can be recommended for preemptive therapy.


Assuntos
Infecções por Citomegalovirus/tratamento farmacológico , Citosina/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Organofosfonatos , Compostos Organofosforados/administração & dosagem , Adolescente , Adulto , Antivirais/administração & dosagem , Antivirais/normas , Antivirais/toxicidade , Criança , Pré-Escolar , Cidofovir , Infecções por Citomegalovirus/etiologia , Infecções por Citomegalovirus/prevenção & controle , Citosina/análogos & derivados , Citosina/normas , Citosina/toxicidade , Coleta de Dados , Avaliação de Medicamentos , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Compostos Organofosforados/normas , Compostos Organofosforados/toxicidade , Insuficiência Renal/induzido quimicamente , Insuficiência Renal/virologia , Estudos Retrospectivos , Taxa de Sobrevida , Transplante Homólogo/efeitos adversos , Resultado do Tratamento
12.
J Rheumatol ; 18(8): 1158-62, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1941815

RESUMO

Levels of serum osteocalcin (OC) are increased in diseases with high bone turnover. We determined OC levels in (1) 15 patients with definite rheumatoid arthritis (RA) in early stages according to Steinbrocker's functional class FC I-II, (2) 40 patients at advanced stages (FC III-IV) and (3) 17 patients with late RA (onset at age of 65 or more). Sixty-two healthy volunteers, divided into 3 subgroups corresponding to the patients, and 19 patients with primary fibromyalgia syndrome (FMS) served as controls. All patients were included in a short term as well as a longitudinal study over one year. Mean OC levels were significantly elevated in patients with late onset RA compared with healthy controls (p = 0.037), while the OC values in early RA FC I-II and advanced RA FC III-IV did not differ significantly from the corresponding control group and the patients with FMS. The late RA group showed a positive correlation between OC and the erythrocyte sedimentation rate (ESR) (r = 0.641, p = 0.007) with a significant decrease of OC (p less than 0.01) as well as ESR (p = 0.047) over one year. We conclude increased OC levels correlate with disease activity in older patients with active RA, suggesting impaired bone turnover. This finding supports the picture of heterogeneity in RA with more late onset patients displaying "high bone turnover."


Assuntos
Artrite Reumatoide/sangue , Osso e Ossos/metabolismo , Osteocalcina/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite Reumatoide/epidemiologia , Biomarcadores/sangue , Sedimentação Sanguínea , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
13.
Fortschr Kieferorthop ; 51(5): 293-6, 1990 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-2262183

RESUMO

60 twins were investigated between the age of ten and 18 years to obtain information about inheritance of tooth-crown size and growth of alveolar bone. The results suggest genetically controlled interaction between tooth germs during their formation. The intrapair differences decrease between ten and 18 years for the alveolar bone diameters. This is an advise for stronger genetically influences in higher age and an etiological factor for relapse after orthodontic treatment.


Assuntos
Dentição , Mandíbula/crescimento & desenvolvimento , Maxila/crescimento & desenvolvimento , Gêmeos Dizigóticos , Gêmeos Monozigóticos , Adolescente , Análise de Variância , Criança , Genética Médica , Humanos , Trigêmeos
14.
Klin Wochenschr ; 65(22): 1095-100, 1987 Nov 16.
Artigo em Alemão | MEDLINE | ID: mdl-3501036

RESUMO

The decoupling of bone formation and bone resorption causes an insidious bone loss that is responsible for the negative skeletal balance in the frequent form of low turnover osteoporosis. The reduction of bone formation can hardly be verified by clinical methods. Osteocalcin, a non-collagenous bone protein, has proved to be a useful new indicator of bone formation. To establish its predictable value, plasma levels of osteocalcin were compared to conventional serological data of bone turnover and to histomorphometric parameters of iliac crest trabecular bone. In cases of osteoporosis with normal bone turnover activity (as confirmed by histomorphometry) no differences were observed in any of our laboratory data including osteocalcin. However, there was a significant lower mean serum level of osteocalcin in a group of patients with histomorphometrically proven low turnover osteoporosis in comparison to those with normal bone turnover. Serum levels of osteocalcin below 2.0 ng/ml seem to indicate a low turnover in the individual case of osteoporosis while this is unlikely when serum levels above 6.0 ng/ml are measured (according to our RIA).


Assuntos
Proteínas de Ligação ao Cálcio/sangue , Osteoporose/patologia , Adulto , Idoso , Biópsia , Osso e Ossos/patologia , Cálcio/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteocalcina , Fósforo/sangue
15.
Dtsch Med Wochenschr ; 110(38): 1442-6, 1985 Sep 20.
Artigo em Alemão | MEDLINE | ID: mdl-3875469

RESUMO

Osteocalcin is synthesized by osteoblasts and its concentration in serum is increased when bone metabolism is raised. Radioimmunoassay of serum from 88 healthy adults gave a mean osteocalcin value for the whole group of 4.11 +/- 1.43 ng/ml. The level rose with age. In seven patients with primary hyperparathyroidism the mean value was markedly raised to 19.37 +/- 9.2 ng/ml, in 23 with metastasizing carcinoma of the breast it was elevated to 6.57 +/- 2.98 ng/ml. Serial measurements in 14 female patients over seven months revealed different changes in osteocalcin and alkaline phosphatase in some of them. In patients with breast cancer and soft-tissue metastases or without metastases both osteocalcin and alkaline phosphatase levels were normal. Three of 17 patients with multiple myeloma had increased osteocalcin levels. These results indicate that it is clinically helpful to know osteocalcin levels in primary hyperparathyroidism. Determination of osteocalcin concentration, in addition to that of alkaline phosphatase, can be of value in the postmastectomy management of patients with breast cancer, especially in the early recognition of bone metastases. The diagnostic value of osteocalcin levels in multiple myeloma remains undecided.


Assuntos
Osso e Ossos/metabolismo , Proteínas de Ligação ao Cálcio/sangue , Adolescente , Adulto , Fatores Etários , Idoso , Fosfatase Alcalina/sangue , Neoplasias Ósseas/secundário , Neoplasias da Mama/sangue , Cálcio/sangue , Feminino , Humanos , Hiperparatireoidismo/sangue , Masculino , Pessoa de Meia-Idade , Osteocalcina , Neoplasias de Tecidos Moles/secundário
16.
IEEE Trans Pattern Anal Mach Intell ; 4(5): 544-51, 1982 May.
Artigo em Inglês | MEDLINE | ID: mdl-21869075

RESUMO

In pattern matching a basic problem is to determine one or more vectors X that maximize an objective function which is a sum of functions of components of X. When this problem is solved by dynamic programming CPU time and storage requirements grow explosively as the amount of intervariable interaction in the objective function increases. This explosion may be reduced by departing from the traditional dynamic programming method of eliminating successive variables and instead determining a constraint relation between each variable and all others with which it interacts. Discrete relaxation is used to accelerate a backtrack search to find all vectors that satisfy all such constraints. Optimization is achieved by evaluating the objective function for all such vectors. This new method of optimization has been experimentally compared with a classical dynamic programming algorithm running with the same pseudorandomly generated objective functions.

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