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1.
Entropy (Basel) ; 23(4)2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33806048

RESUMO

An information-theoretic approach for detecting causality and information transfer is used to identify interactions of solar activity and interplanetary medium conditions with the Earth's magnetosphere-ionosphere systems. A causal information transfer from the solar wind parameters to geomagnetic indices is detected. The vertical component of the interplanetary magnetic field (Bz) influences the auroral electrojet (AE) index with an information transfer delay of 10 min and the geomagnetic disturbances at mid-latitudes measured by the symmetric field in the H component (SYM-H) index with a delay of about 30 min. Using a properly conditioned causality measure, no causal link between AE and SYM-H, or between magnetospheric substorms and magnetic storms can be detected. The observed causal relations can be described as linear time-delayed information transfer.

2.
Entropy (Basel) ; 22(5)2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-33286343

RESUMO

The continuously expanding toolbox of nonlinear time series analysis techniques has recently highlighted the importance of dynamical complexity to understand the behavior of the complex solar wind-magnetosphere-ionosphere-thermosphere coupling system and its components. Here, we apply new such approaches, mainly a series of entropy methods to the time series of the Earth's magnetic field measured by the Swarm constellation. We show successful applications of methods, originated from information theory, to quantitatively study complexity in the dynamical response of the topside ionosphere, at Swarm altitudes, focusing on the most intense magnetic storm of solar cycle 24, that is, the St. Patrick's Day storm, which occurred in March 2015. These entropy measures are utilized for the first time to analyze data from a low-Earth orbit (LEO) satellite mission flying in the topside ionosphere. These approaches may hold great potential for improved space weather nowcasts and forecasts.

3.
Sci Rep ; 8(1): 16987, 2018 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-30451956

RESUMO

The dynamical relationship between magnetic storms and magnetospheric substorms is one of the most controversial issues of contemporary space research. Here, we address this issue through a causal inference approach to two corresponding indices in conjunction with several relevant solar wind variables. We find that the vertical component of the interplanetary magnetic field is the strongest and common driver of both storms and substorms. Further, our results suggest, at least based on the analyzed indices, that there is no statistical evidence for a direct or indirect dependency between substorms and storms and their statistical association can be explained by the common solar drivers. Given the powerful statistical tests we performed (by simultaneously taking into account time series of indices and solar wind variables), a physical mechanism through which substorms directly or indirectly drive storms or vice versa is, therefore, unlikely.

4.
J Oral Maxillofac Surg ; 66(1): 16-20, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18083410

RESUMO

PURPOSE: To present a treatment plan for localized mucosa-associated lymphoid tissue lymphoma of the orbit in order to preserve vital structures and function from the side effects of radiotherapy. MATERIALS AND METHODS: Study of 2 clinical cases by means of clinical and radiologic examination, with 2 and 3 years follow-up, respectively. RESULTS: Immediate remission of the disease after 6 cycles of chemotherapy, with no signs of recurrence after 2 and 3 years. Clinical examination of the oculomotor mechanism and visual activity gave excellent results. CONCLUSION: Although radiotherapy is preferable for localized lymphoproliferative lesions, chemotherapy should also be considered as an effective treatment that preserves the integrity and function of the ocular adnexa.


Assuntos
Linfoma de Zona Marginal Tipo Células B/tratamento farmacológico , Neoplasias Orbitárias/tratamento farmacológico , Idoso , Antígenos CD/análise , Biomarcadores Tumorais/análise , Quimioterapia Combinada , Exoftalmia/etiologia , Feminino , Humanos , Linfoma de Zona Marginal Tipo Células B/patologia , Linfoma de Zona Marginal Tipo Células B/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Tomografia Computadorizada por Raios X , Resultado do Tratamento
5.
Acta Histochem ; 108(5): 343-50, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16919707

RESUMO

The immunohistochemical detection of neurofilament protein (NF), peripherin (PRP), S100B protein (S100B), neuron-specific enolase (NSE) and chromogranin-A (CgA) has been studied in nerve fibres and bundles of human dental pulp. This was done in order to identify possible differences in the distribution pattern of the above markers between normal and inflamed pulp and, further, to evaluate their potential use as peripheral markers of dental innervation as well as objective markers for the determination of the extent of inflammation. Both normal and inflamed human dental pulp showed positive immunolabelling for NF, S100B and NSE and lack of labelling for PRP and CgA protein. An increased density of NF, S100B and NSE immunoreactive nerve fibres was observed in inflamed pulp samples compared to non-inflamed. The findings of this study suggest the possible application of NF, S100B and NSE as markers of dental innervation. Furthermore, they may be useful for the determination of the extent of pulpal inflammation, and might be utilized in alternative modalities of biological pulp therapy to reduce the inflammation process. The absence of CgA immunolabelling implies the presumptive absence of neuroendocrine antigens, while further research is required in order to clarify the involvement of PRP in dental pulp.


Assuntos
Antígenos/metabolismo , Polpa Dentária/metabolismo , Fatores de Crescimento Neural/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Fosfopiruvato Hidratase/metabolismo , Pulpite/metabolismo , Proteínas S100/metabolismo , Adulto , Antígenos/imunologia , Cromogranina A/imunologia , Cromogranina A/metabolismo , Polpa Dentária/citologia , Polpa Dentária/crescimento & desenvolvimento , Humanos , Imuno-Histoquímica , Proteínas de Filamentos Intermediários/imunologia , Proteínas de Filamentos Intermediários/metabolismo , Glicoproteínas de Membrana/imunologia , Glicoproteínas de Membrana/metabolismo , Fatores de Crescimento Neural/imunologia , Proteínas do Tecido Nervoso/imunologia , Proteínas de Neurofilamentos/imunologia , Proteínas de Neurofilamentos/metabolismo , Neurônios/imunologia , Periferinas , Fosfopiruvato Hidratase/imunologia , Pulpite/patologia , Subunidade beta da Proteína Ligante de Cálcio S100 , Proteínas S100/imunologia
6.
Acta Neuropathol ; 107(6): 546-52, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15085358

RESUMO

Emerin is an inner nuclear membrane protein that is mutated or not expressed in patients with X-linked Emery-Dreifuss muscular dystrophy (X-EDMD/EMD). Cytoplasmic localization of emerin in cultured cells or tissues has been reported, although this remains a controversial issue. Tubular aggregates (TAs) are pathological structures seen in the sarcoplasm of human skeletal muscle fibers in various disorders. The TAs derive from the sarcoplasmic reticulum (SR) and represent, probably, an adaptive response of the SR to various insults to the muscle fibers. In the present study, we present immunohistochemical evidence of emerin expression in TAs. Muscle biopsies with tubular aggregates from four male, unrelated patients were studied. The percentage of muscle fibers containing TAs varied between 5 and 20%. Routine histochemistry revealed intense reaction of TAs with NADH-TR, AMPDA, and NSE, but not with COX, SDH, myosin ATPase (pH 9.4, 4.3, 4.6), PAS, and Oil red O staining. Immunohistochemical study revealed strong immunostaining of TAs with antibodies against emerin and 7 SERCA2-ATPase. Immunostaining of TAs was also seen with antibodies against heat shock protein and dysferlin, but not with antibodies to lamin A, dystrophin, adhalin, beta, gamma, delta sarcoglycans, and merosin. These results suggest that emerin, an inner nuclear membrane protein, is present at the TAs. The interpretation and significance of this finding is discussed in relation to experimental data suggesting that normal emerin localization at the inner nuclear membrane depends on lamin A and mutations in the N-terminal domain of emerin cause mislocalization of the protein to the sarcoplasmic membranes.


Assuntos
Proteínas de Membrana/metabolismo , Músculo Esquelético/metabolismo , Distrofia Muscular de Emery-Dreifuss/metabolismo , Miopatias Congênitas Estruturais/metabolismo , Timopoietinas/metabolismo , AMP Desaminase/metabolismo , Adulto , ATPases Transportadoras de Cálcio/metabolismo , Ciclo-Oxigenase 2 , Humanos , Hidroliases/metabolismo , Imuno-Histoquímica/métodos , Isoenzimas/metabolismo , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Músculo Esquelético/ultraestrutura , Distrofia Muscular de Emery-Dreifuss/patologia , Miopatias Congênitas Estruturais/patologia , NAD/metabolismo , Proteínas Nucleares , Fosfopiruvato Hidratase/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático
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