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1.
Opt Express ; 26(15): 19247-19258, 2018 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-30114183

RESUMO

Based on the reciprocity theorem, we present a formalism to calculate the power emitted by a dipole source into a particular propagating mode leaving an open optical system. The open system is completely arbitrary and the approach can be used in analytical calculations but may also be combined with numerical electromagnetic solvers to describe the emission of light sources into complex systems. We exemplify the use of the formalism in numerical simulations by analyzing the emission of a dipole that is placed inside a cavity with connected single mode exit waveguide. Additionally, we show at the example of a practical ring resonator system how the approach can be applied to systems that offer multiple electromagnetic energy decay channels. As a consequence of its inherent simplicity and broad applicability, the approach may serve as a powerful and practical tool for engineering light-matter-interaction in a variety of active optical systems.

2.
Neuroscience ; 207: 274-82, 2012 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-22314319

RESUMO

The α7* nicotinic acetylcholine receptor encoded by CHRNA7 (human)/Chrna7 (mice) regulates the release of both the inhibitory neurotransmitter GABA and the excitatory neurotransmitter glutamate in the hippocampal formation. A heterozygous (Het) deletion at 15q13.3 containing CHRNA7 is associated with increased risk for schizophrenia, autism, and epilepsy. Each of these diseases are characterized by abnormalities in excitatory and inhibitory hippocampal circuit function. Reduced Chrna7 expression results in decreased hippocampal α7* receptor density, abnormal hippocampal auditory sensory processing, and increased hippocampal CA3 pyramidal neuron activity in C3H mice Het for a null mutation in Chrna7. These abnormalities demonstrate that decreased Chrna7 expression alters hippocampal inhibitory circuit function. The current study examined the specific impact of reduced Chrna7 expression on hippocampal inhibitory circuits by measuring the levels of GABA, GABA(A) receptors, the GABA synthetic enzyme l-glutamic acid decarboxylase-65 (GAD-65), and the vesicular GABA transporter 1 (GAT-1) in wild-type (Chrna7 +/+) and Het (Chrna7 +/-) C3H α7 mice of both genders. GAD-65 levels were significantly decreased in male and female Het C3H α7 mice, whereas GABA(A) receptors were significantly reduced only in male Het C3H α7 mice. No changes in GABA and GAT-1 levels were detected. These data suggest that reduced CHRNA7 expression may contribute to the abnormalities in hippocampal inhibitory circuits observed in schizophrenia, autism, and/or epilepsy.


Assuntos
Hipocampo/metabolismo , Inibição Neural/genética , Receptores Nicotínicos/deficiência , Animais , Transtorno Autístico/genética , Transtorno Autístico/metabolismo , Transtorno Autístico/fisiopatologia , Modelos Animais de Doenças , Epilepsia/genética , Epilepsia/metabolismo , Epilepsia/fisiopatologia , Feminino , Predisposição Genética para Doença/genética , Hipocampo/fisiopatologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Nicotínicos/biossíntese , Receptores Nicotínicos/genética , Esquizofrenia/genética , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatologia , Caracteres Sexuais , Receptor Nicotínico de Acetilcolina alfa7
3.
Physiol Behav ; 73(1-2): 121-4, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11399303

RESUMO

After weaning, adult female meadow voles were maintained for 7 weeks in either long (LD, 14 h light/day) or short photoperiods (SD, 10 h light/day). They were then ovariectomized and implanted with 3-week, timed-release estrogen pellets (0.0, 0.001, 0.05, or 0.5 mg/pellet of 17-beta-estradiol). An additional group received a sham ovariectomy (intact) and a 0.0-mg/pellet control (no estrogen) pellet. One week after surgery, females were paired with an LD sexually experienced male. Each pair was videotaped continuously until the first intromission or for 2 weeks. LD sham animals mated significantly earlier than did SD sham animals (P=.05). However, there were no differences in mating latencies between LD and SD control groups or between any of the LD and SD groups receiving estrogen replacement (P>.05). In addition, no ovariectomized animals receiving either the control or the 0.001-mg/pellet estrogen dosage mated within the 2-week time period, while all shams and all animals receiving either the 0.05- or 0.5-mg/pellet doses mated. The results indicate that there is some minimal amount of estrogen that is necessary for meadow voles to enter behavioral estrus and that LD and SD females do not differ in their sensitivity to estrogen, since animals in both photoperiods mate with similar latencies as long as enough estrogen is present.


Assuntos
Arvicolinae/fisiologia , Ritmo Circadiano/fisiologia , Estrogênios/fisiologia , Comportamento Sexual Animal/fisiologia , Animais , Relação Dose-Resposta a Droga , Implantes de Medicamento , Estradiol/farmacologia , Feminino , Iluminação , Masculino , Comportamento Sexual Animal/efeitos dos fármacos
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