Sex-Specific Consequences of Neonatal Stress on Cardio-Respiratory Inhibition Following Laryngeal Stimulation in Rat Pups

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Baldy, Cécile; Chamberland, Simon

2017-01-01

Abstract The presence of liquid near the larynx of immature mammals triggers prolonged apneas with significant O2 desaturations and bradycardias. When excessive, this reflex (the laryngeal chemoreflex; LCR) can be fatal. Our understanding of the origins of abnormal LCR are limited; however, perinatal stress and male sex are risk factors for cardio-respiratory failure in infants. Because exposure to stress during early life has deleterious and sex-specific consequences on brain development it is plausible that respiratory reflexes are vulnerable to neuroendocrine dysfunction. To address this issue, we tested the hypothesis that neonatal maternal separation (NMS) is sufficient to exacerbate LCR-induced cardio-respiratory inhibition in anesthetized rat pups. Stressed pups were separated from their mother 3 h/d from postnatal days 3 to 12. At P14–P15, pups were instrumented to monitor breathing, O2 saturation (Spo2), and heart rate. The LCR was activated by water injections near the larynx (10 µl). LCR-induced apneas were longer in stressed pups than controls; O2 desaturations and bradycardias were more profound, especially in males. NMS increased the frequency and amplitude of spontaneous EPSCs (sEPSCs) in the dorsal motor nucleus of the vagus (DMNV) of males but not females. The positive relationship between corticosterone and testosterone observed in stressed pups (males only) suggests that disruption of neuroendocrine function by stress is key to sex-based differences in abnormal LCR. Because testosterone application onto medullary slices augments EPSC amplitude only in males, we propose that testosterone-mediated enhancement of synaptic connectivity within the DMNV contributes to the male bias in cardio-respiratory inhibition following LCR activation in stressed pups. PMID:29308430

Nitric oxide-related species inhibit evoked neurotransmission but enhance spontaneous miniature synaptic currents in central neuronal cultures

OpenAIRE

Pan, Zhuo-Hua; Segal, Michael M.; Lipton, Stuart A.

1996-01-01

Nitric oxide (NO·) does not react significantly with thiol groups under physiological conditions, whereas a variety of endogenous NO donor molecules facilitate rapid transfer to thiol of nitrosonium ion (NO+, with one less electron than NO·). Here, nitrosonium donors are shown to decrease the efficacy of evoked neurotransmission while increasing the frequency of spontaneous miniature excitatory postsynaptic currents (mEPSCs). In contrast, pure NO· donors have littl...

Different AMPA receptor subtypes mediate the distinct kinetic components of a biphasic EPSC in hippocampal interneurons

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Todd eStincic

2015-05-01

Full Text Available CA1 hippocampal interneurons at the border between stratum radiatum and stratum lacunosum-moleculare have AMPA receptor (AMPAR-mediated excitatory postsynaptic currents (EPSCs that consist of two distinct phases: a typical fast component (FC, and a highly unusual slow component (SC that persists for hundreds of milliseconds. To determine whether these kinetically distinct components of the EPSC are mediated by distinct AMPAR subpopulations, we examined the relative contributions of GluA2-containing and –lacking AMPARs to the SC. GluA2-containing AMPARs mediated the majority of the FC whereas GluA2-lacking AMPARs preferentially generated the SC. When glutamate uptake through the glial glutamate transporter EAAT1 was inhibited, spill over-mediated AMPAR activation recruited an even slower third kinetic component that persisted for several seconds; however, this spillover-mediated current was mediated predominantly by GluA2-containing AMPARs and therefore was clearly distinct from the SC when uptake is intact. Thus, different AMPAR subpopulations that vary in GluA2 content mediate the distinct components of the AMPAR EPSC. The SC is developmentally downregulated in mice, declining after the second postnatal week. This downregulation affects both GluA2-containing and GluA2-lacking AMPARs mediating the SC, and is not accompanied by developmental changes in the GluA2 content of AMPARs underlying the FC. Thus, the downregulation of the SC appears to be independent of synaptic GluA2 expression, suggesting the involvement of another AMPAR subunit or an auxiliary protein. Our results therefore identify GluA2-dependent and GluA2-independent determinants of the SC: GluA2-lacking AMPARs preferentially contribute to the SC, while the developmental downregulation of the SC is independent of GluA2 content.

Kalirin, a key player in synapse formation, is implicated in human diseases.

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Mandela, Prashant; Ma, Xin-Ming

2012-01-01

Synapse formation is considered to be crucial for learning and memory. Understanding the underlying molecular mechanisms of synapse formation is a key to understanding learning and memory. Kalirin-7, a major isoform of Kalirin in adult rodent brain, is an essential component of mature excitatory synapses. Kalirin-7 interacts with multiple PDZ-domain-containing proteins including PSD95, spinophilin, and GluR1 through its PDZ-binding motif. In cultured hippocampal/cortical neurons, overexpression of Kalirin-7 increases spine density and spine size whereas reduction of endogenous Kalirin-7 expression decreases synapse number, and spine density. In Kalirin-7 knockout mice, spine length, synapse number, and postsynaptic density (PSD) size are decreased in hippocampal CA1 pyramidal neurons; these morphological alterations are accompanied by a deficiency in long-term potentiation (LTP) and a decreased spontaneous excitatory postsynaptic current (sEPSC) frequency. Human Kalirin-7, also known as Duo or Huntingtin-associated protein-interacting protein (HAPIP), is equivalent to rat Kalirin-7. Recent studies show that Kalirin is relevant to many human diseases such as Huntington's Disease, Alzheimer's Disease, ischemic stroke, schizophrenia, depression, and cocaine addiction. This paper summarizes our recent understanding of Kalirin function.

Neurotensin enhances glutamatergic EPSCs in VTA neurons by acting on different neurotensin receptors.

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Bose, Poulomee; Rompré, Pierre-Paul; Warren, Richard A

2015-11-01

Neurotensin (NT) is an endogenous neuropeptide that modulates dopamine and glutamate neurotransmission in several limbic regions innervated by neurons located in the ventral tegmental area (VTA). While several studies showed that NT exerted a direct modulation on VTA dopamine neurons less is known about its role in the modulation of glutamatergic neurotransmission in this region. The present study was aimed at characterising the effects of NT on glutamate-mediated responses in different populations of VTA neurons. Using whole cell patch clamp recording technique in horizontal rat brain slices, we measured the amplitude of glutamatergic excitatory post-synaptic currents (EPSCs) evoked by electrical stimulation of VTA afferents before and after application of different concentrations of NT1-13 or its C-terminal fragment, NT8-13. Neurons were classified as either Ih(+) or Ih(-) based on the presence or absence of a hyperpolarisation activated cationic current (Ih). We found that NT1-13 and NT8-13 produced comparable concentration dependent increase in the amplitude of EPSCs in both Ih(+) and Ih(-) neurons. In Ih(+) neurons, the enhancement effect of NT8-13 was blocked by both antagonists, while in Ih(-) neurons it was blocked by the NTS1/NTS2 antagonist, SR142948A, but not the preferred NTS1 antagonist, SR48692. In as much as Ih(-) neurons are non-dopaminergic neurons and Ih(+) neurons represent both dopamine and non-dopamine neurons, we can conclude that NT enhances glutamatergic mediated responses in dopamine, and in a subset of non-dopamine, neurons by acting respectively on NTS1 and an NT receptor other than NTS1. Copyright © 2015 Elsevier Inc. All rights reserved.

Endomorphin-2 Inhibits the Activity of the Spinoparabrachial Projection Neuron through Presynaptic Mechanisms in the Spinal Dorsal Horn in Rats

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Jun-Bin Yin

2018-03-01

Full Text Available Background/Aims: Spinal dorsal horn (SDH is one of the most important regions for analgesia produced by endomorphin-2 (EM2, which has a higher affinity and specificity for the µ-opioid receptor (MOR than morphine. Many studies have focused on substantia gelatinosa (SG, lamina II neurons to elucidate the cellular basis for its antinociceptive effects. However, the complicated types and local circuits of interneurons in the SG make it difficult to understand the real effects of EM2. Therefore, in the present study, we examined the effects of EM2 on projection neurons (PNs in lamina I. Methods: Tracing, immunofluoresence, and immunoelectron methods were used to examine the morphological connections between EM2-immunoreactive (-ir terminals and PNs. By using in vitro whole cell patch clamp recording technique, we investigated the functional effects of EM2 on PNs. Results: EM2-ir afferent terminals directly contacted PNs projecting to the parabrachial nucleus in lamina I. Their synaptic connections were further confirmed by immunoelectron microscopy, most of which were asymmetric synapses. It was found that EM2 had a strong inhibitory effect on the frequency, but not amplitude, of the spontaneous excitatory postsynaptic current (sEPSC of the spinoparabrachial PNs in lamina I, which could be reversed by MOR antagonist CTOP. However, their spontaneous inhibitory postsynaptic current (sIPSC and intrinsic properties were not changed after EM2 application. Conclusion: Applying EM2 to the SDH could produce analgesia through inhibiting the activities of the spinoparabrachial PNs in lamina I by reducing presynaptic neurotransmitters release from the primary afferent terminals.

On the correlation between deformation twinning and Lueders-like deformation in an extruded Mg alloy: In situ neutron diffraction and EPSC.4 modelling

International Nuclear Information System (INIS)

Muransky, O.; Barnett, M.R.; Luzin, V.; Vogel, S.

2010-01-01

The current work focuses on the yielding and immediate post-yielding deformation of fine-grained and coarse-grained ZM20 Mg alloys obtained by extrusion. Compressive deformations along the extrusion direction, known to be governed by profuse twinning are examined in detail. It is shown that the fine-grained alloy exhibits Lueders-like plateaux suggesting heterogeneous transition from elastic to plastic deformation. This is due to the cooperative twinning of neighbouring grains which is promoted in the fine-grained alloy by the high internal stresses borne by the parent grain families in the vicinity of yielding, and the auto-catalytic nature of twin nucleation. The elasto-plastic response of tested alloys was also simulated using version 4 of the Elasto-Plastic Self-Consistent (EPSC) model. The finite initial fraction (FIF) assumption is employed to account for the stress relaxation related to the twin nucleation process. It is shown that the new EPSC.4 model is superior to its previous version as it enables realistic predictions of the development of elastic lattice strains in variously oriented grain families and the macroscopic stress-strain response of a polycrystalline aggregate undergoing profuse twinning.

Enhanced inhibitory synaptic transmission in the spinal dorsal horn mediates antinociceptive effects of TC-2559

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2011-01-01

Background TC-2559 is a selective α4β2 subtype of nicotinic acetylcholine receptor (nAChR) partial agonist and α4β2 nAChR activation has been related to antinociception. The aim of this study is to investigate the analgesic effect of TC-2559 and its underlying spinal mechanisms. Results 1) In vivo bioavailability study: TC-2559 (3 mg/kg) had high absorption rate in rats with maximal total brain concentration reached over 4.6 μM within first 15 min after administration and eliminated rapidly with brain half life of about 20 min after injection. 2) In vivo behavioral experiments: TC-2559 exerts dose dependent antinociceptive effects in both formalin test in mice and chronic constriction injury (CCI) model in rats by activation of α4β2 nAChRs; 3) Whole-cell patch-clamp studies in the superficial dorsal horn neurons of the spinal cord slices: perfusion of TC-2559 (2 μM) significantly increased the frequency, but not amplitude of spontaneous inhibitory postsynaptic currents (sIPSCs). The enhancement of sIPSCs was blocked by pre-application of DHβE (2 μM), a selective α4β2 nicotinic receptor antagonist. Neither the frequency nor the amplitude of spontaneous excitatory postsynaptic currents (sEPSCs) of spinal dorsal horn neurons were affected by TC-2559. Conclusions Enhancement of inhibitory synaptic transmission in the spinal dorsal horn via activation of α4β2 nAChRs may be one of the mechanisms of the antinociceptive effects of TC-2559 on pathological pain models. It provides further evidence to support the notion that selective α4β2 subtype nAChR agonist may be developed as new analgesic drug for the treatment of neuropathic pain. PMID:21816108

Glutamatergic synaptic currents of nigral dopaminergic neurons follow a postnatal developmental sequence

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Edouard ePearlstein

2015-05-01

Full Text Available The spontaneous activity pattern of adult dopaminergic (DA neurons of the substantia nigra pars compacta (SNc results from interactions between intrinsic membrane conductances and afferent inputs. In adult SNc DA neurons, low-frequency tonic background activity is generated by intrinsic pacemaker mechanisms, whereas burst generation depends on intact synaptic inputs in particular the glutamatergic ones. Tonic DA release in the striatum during pacemaking is required to maintain motor activity, and burst firing evokes phasic DA release, necessary for cue-dependent learning tasks. However, it is still unknown how the firing properties of SNc DA neurons mature during postnatal development before reaching the adult state. We studied the postnatal developmental profile of spontaneous and evoked AMPA and NMDA receptor-mediated excitatory postsynaptic currents (EPSCs in SNc DA neurons in brain slices from immature (postnatal days P4-10 and young adult (P30-50 tyrosine hydroxylase (TH-GFP mice. We found that somato-dendritic fields of SNc DA neurons are already mature at P4-10. In contrast, spontaneous glutamatergic EPSCs show a developmental sequence. Spontaneous NMDA EPSCs in particular are larger and more frequent in immature SNc DA neurons than in young adult ones and have a bursty pattern. They are mediated by GluN2B and GluN2D subunit-containing NMDA receptors. The latter generate long-lasting, DQP1105-sensitive, spontaneous EPSCs, which are transiently recorded during this early period. Due to high NMDA activity, immature SNc DA neurons generate large and long lasting NMDA receptor-dependent (APV-sensitive bursts in response to the stimulation of the subthalamic nucleus. We conclude that the transient high NMDA activity allows calcium influx into the dendrites of developing SNc DA neurons.

Spontaneous mutation reveals influence of exopolysaccharide on Lactobacillus johnsonii surface characteristics.

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Horn, Nikki; Wegmann, Udo; Dertli, Enes; Mulholland, Francis; Collins, Samuel R A; Waldron, Keith W; Bongaerts, Roy J; Mayer, Melinda J; Narbad, Arjan

2013-01-01

As a competitive exclusion agent, Lactobacillus johnsonii FI9785 has been shown to prevent the colonization of selected pathogenic bacteria from the chicken gastrointestinal tract. During growth of the bacterium a rare but consistent emergence of an altered phenotype was noted, generating smooth colonies in contrast to the wild type rough form. A smooth colony variant was isolated and two-dimensional gel analysis of both strains revealed a protein spot with different migration properties in the two phenotypes. The spot in both gels was identified as a putative tyrosine kinase (EpsC), associated with a predicted exopolysaccharide gene cluster. Sequencing of the epsC gene from the smooth mutant revealed a single substitution (G to A) in the coding strand, resulting in the amino acid change D88N in the corresponding gene product. A native plasmid of L. johnsonii was engineered to produce a novel vector for constitutive expression and this was used to demonstrate that expression of the wild type epsC gene in the smooth mutant produced a reversion to the rough colony phenotype. Both the mutant and epsC complemented strains had increased levels of exopolysaccharides compared to the wild type strain, indicating that the rough phenotype is not solely associated with the quantity of exopolysaccharide. Another gene in the cluster, epsE, that encoded a putative undecaprenyl-phosphate galactosephosphotransferase, was deleted in order to investigate its role in exopolysaccharide biosynthesis. The ΔepsE strain exhibited a large increase in cell aggregation and a reduction in exopolysaccharide content, while plasmid complementation of epsE restored the wild type phenotype. Flow cytometry showed that the wild type and derivative strains exhibited clear differences in their adhesive ability to HT29 monolayers in tissue culture, demonstrating an impact of EPS on surface properties and bacteria-host interactions.

Spontaneous mutation reveals influence of exopolysaccharide on Lactobacillus johnsonii surface characteristics.

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Nikki Horn

Full Text Available As a competitive exclusion agent, Lactobacillus johnsonii FI9785 has been shown to prevent the colonization of selected pathogenic bacteria from the chicken gastrointestinal tract. During growth of the bacterium a rare but consistent emergence of an altered phenotype was noted, generating smooth colonies in contrast to the wild type rough form. A smooth colony variant was isolated and two-dimensional gel analysis of both strains revealed a protein spot with different migration properties in the two phenotypes. The spot in both gels was identified as a putative tyrosine kinase (EpsC, associated with a predicted exopolysaccharide gene cluster. Sequencing of the epsC gene from the smooth mutant revealed a single substitution (G to A in the coding strand, resulting in the amino acid change D88N in the corresponding gene product. A native plasmid of L. johnsonii was engineered to produce a novel vector for constitutive expression and this was used to demonstrate that expression of the wild type epsC gene in the smooth mutant produced a reversion to the rough colony phenotype. Both the mutant and epsC complemented strains had increased levels of exopolysaccharides compared to the wild type strain, indicating that the rough phenotype is not solely associated with the quantity of exopolysaccharide. Another gene in the cluster, epsE, that encoded a putative undecaprenyl-phosphate galactosephosphotransferase, was deleted in order to investigate its role in exopolysaccharide biosynthesis. The ΔepsE strain exhibited a large increase in cell aggregation and a reduction in exopolysaccharide content, while plasmid complementation of epsE restored the wild type phenotype. Flow cytometry showed that the wild type and derivative strains exhibited clear differences in their adhesive ability to HT29 monolayers in tissue culture, demonstrating an impact of EPS on surface properties and bacteria-host interactions.

Selective alterations of NMDAR function and plasticity in D1 and D2 medium spiny neurons in the nucleus accumbens shell following chronic intermittent ethanol exposure.

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Renteria, Rafael; Maier, Esther Y; Buske, Tavanna R; Morrisett, Richard A

2017-01-01

A major mouse model widely adopted in recent years to induce pronounced ethanol intake is the ethanol vapor model known as "CIE" or "Chronic Intermittent Ethanol." One critical question concerning this model is whether the rapid induction of high blood ethanol levels for such short time periods is sufficient to induce alterations in N-methyl-d-aspartate receptor (NMDAR) function which may contribute to excessive ethanol intake. In this study, we determined whether such short term intermittent ethanol exposure modulates NMDAR function as well as other prominent electrophysiological properties and the expression of plasticity in both D1 (D1+) and D2 (D1-) dopamine receptor expressing medium spiny neurons (MSNs) in the nucleus accumbens (NAc) shell. To distinguish between the two subtypes of MSNs in the NAc we treated Drd1a-TdTomato transgenic mice with CIE vapor and electrophysiological recordings were conducted 24 h after the last vapor exposure. To investigate CIE induced alterations in plasticity, long-term depression (LTD) was induced by pairing low frequency stimulation (LFS) with post synaptic depolarization. In ethanol naïve mice, LFS induced synaptic depression (LTD) was apparent exclusively in D1+ MSNs. Whereas in slices prepared from CIE treated mice, LFS induced synaptic potentiation (LTP) in D1+ MSNs. Furthermore, following CIE exposure, LFS now produced LTD in D1- MSNs. We found that CIE exposure induced an increase in excitability in D1+ MSNs with no change in D1- MSNs. After CIE, we found a significant increase in spontaneous EPSCs (sEPSCs) frequency in D1+ but not D1- MSNs suggesting alterations in baseline α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) mediated signaling. CIE induced changes in NMDAR function were measured using the NMDA/AMPA ratio and input-output curves of isolated NMDAR currents. We observed a significant increase in NMDAR function in D1+ MSNs and a decrease in D1- MSNs after ethanol vapor exposure. The

Corticotrigeminal Projections from the Insular Cortex to the Trigeminal Caudal Subnucleus Regulate Orofacial Pain after Nerve Injury via Extracellular Signal-Regulated Kinase Activation in Insular Cortex Neurons.

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Wang, Jian; Li, Zhi-Hua; Feng, Ban; Zhang, Ting; Zhang, Han; Li, Hui; Chen, Tao; Cui, Jing; Zang, Wei-Dong; Li, Yun-Qing

2015-01-01

Cortical neuroplasticity alterations are implicated in the pathophysiology of chronic orofacial pain. However, the relationship between critical cortex excitability and orofacial pain maintenance has not been fully elucidated. We recently demonstrated a top-down corticospinal descending pain modulation pathway from the anterior cingulate cortex (ACC) to the spinal dorsal horn that could directly regulate nociceptive transmission. Thus, we aimed to investigate possible corticotrigeminal connections that directly influence orofacial nociception in rats. Infraorbital nerve chronic constriction injury (IoN-CCI) induced significant orofacial nociceptive behaviors as well as pain-related negative emotions such as anxiety/depression in rats. By combining retrograde and anterograde tract tracing, we found powerful evidence that the trigeminal caudal subnucleus (Vc), especially the superficial laminae (I/II), received direct descending projections from granular and dysgranular parts of the insular cortex (IC). Extracellular signal-regulated kinase (ERK), an important signaling molecule involved in neuroplasticity, was significantly activated in the IC following IoN-CCI. Moreover, in IC slices from IoN-CCI rats, U0126, an inhibitor of ERK activation, decreased both the amplitude and the frequency of spontaneous excitatory postsynaptic currents (sEPSCs) and reduced the paired-pulse ratio (PPR) of Vc-projecting neurons. Additionally, U0126 also reduced the number of action potentials in the Vc-projecting neurons. Finally, intra-IC infusion of U0126 obviously decreased Fos expression in the Vc, accompanied by the alleviation of both nociceptive behavior and negative emotions. Thus, the corticotrigeminal descending pathway from the IC to the Vc could directly regulate orofacial pain, and ERK deactivation in the IC could effectively alleviate neuropathic pain as well as pain-related negative emotions in IoN-CCI rats, probably through this top-down pathway. These findings may help

Intermittent Theta-Burst Transcranial Magnetic Stimulation Alters Electrical Properties of Fast-Spiking Neocortical Interneurons in an Age-Dependent Fashion.

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Hoppenrath, Kathrin; Härtig, Wolfgang; Funke, Klaus

2016-01-01

Modulation of human cortical excitability by repetitive transcranial magnetic stimulation (rTMS) appears to be in part related to changed activity of inhibitory systems. Our own studies showed that intermittent theta-burst stimulation (iTBS) applied via rTMS to rat cortex primarily affects the parvalbumin-expressing (PV) fast-spiking interneurons (FSIs), evident via a strongly reduced PV expression. We further found the iTBS effect on PV to be age-dependent since no reduction in PV could be induced before the perineuronal nets (PNNs) of FSIs start to grow around postnatal day (PD) 30. To elucidate possible iTBS-induced changes in the electrical properties of FSIs and cortical network activity during cortical critical period, we performed ex vivo-in vitro whole-cell patch clamp recordings from pre-labeled FSIs in the current study. FSIs of verum iTBS-treated rats displayed a higher excitability than sham-treated controls at PD29-38, evident as higher rates of induced action potential firing at low current injections (100-200 pA) and a more depolarized resting membrane potential. This effect was absent in younger (PD26-28) and older animals (PD40-62). Slices of verum iTBS-treated rats further showed higher rates of spontaneous excitatory postsynaptic currents (sEPSCs). Based on these and previous findings we conclude that FSIs are particularly sensitive to TBS during early cortical development, when FSIs show an activity-driven step of maturation which is paralleled by intense growth of the PNNs and subsequent closure of the cortical critical period. Although to be proven further, rTMS may be a possible early intervention to compensate for hypo-activity related mal-development of cortical neuronal circuits.

Changes in inhibitory CA1 network in dual pathology model of epilepsy.

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Ouardouz, Mohamed; Carmant, Lionel

2012-01-01

The combination of two precipitating factors appears to be more and more recognized in patients with temporal lobe epilepsy. Using a two-hit rat model, with a neonatal freeze lesion mimicking a focal cortical malformation combined with hyperthermia-induced seizures mimicking febrile seizures, we have previously reported an increase of inhibition in CA1 pyramidal cells at P20. Here, we investigated the changes affecting excitatory and inhibitory drive onto CA1 interneurons to better define the changes in CA1 inhibitory networks and their paradoxical role in epileptogenesis, using electrophysiological recordings in CA1 hippocampus from rat pups (16-20 d old). We investigated interneurons in CA1 hippocampal area located in stratum oriens (Or) and at the border of strata lacunosum and moleculare (L-M). Our results revealed an increase of the excitatory drive to both types of interneurons with no change in the inhibitory drive. The mechanisms underlying the increase of excitatory synaptic currents (EPSCs) in both types of interneurons are different. In Or interneurons, the amplitude of spontaneous and miniature EPSCs increased, while their frequency was not affected suggesting changes at the post-synaptic level. In L-M interneurons, the frequency of spontaneous EPSCs increases, but the amplitude is not affected. Analyses of miniature EPSCs showed no changes in both their frequency and amplitude. We concluded that L-M interneurons increase in excitatory drive is due to a change in Shaffer collateral axon excitability. The changes described here in CA1 inhibitory network may actually contribute to the epileptogenicity observed in this dual pathology model by increasing pyramidal cell synchronization.

Electrophysical properties, synaptic transmission and neuromodulation in serotonergic caudal raphe neurons.

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Li, Y W; Bayliss, D A

1998-06-01

1. We studied electrophysiological properties, synaptic transmission and modulation by 5-hydroxytryptamine (5-HT) of caudal raphe neurons using whole-cell recording in a neonatal rat brain slice preparation; recorded neurons were identified as serotonergic by post-hoc immunohistochemical detection of tryptophan hydroxylase, the 5-HT-synthesizing enzyme. 2. Serotonergic neurons fired spontaneously (approximately 1 Hz), with maximal steady state firing rates of < 4 Hz. 5-Hydroxytryptamine caused hyperpolarization and cessation of spike activity in these neurons by activating inwardly rectifying K+ conductance via somatodendritic 5-HT1A receptors. 3. Unitary glutamatergic excitatory post-synaptic potentials (EPSP) and currents (EPSC) were evoked in serotonergic neurons by local electrical stimulation. Evoked EPSC were potently inhibited by 5-HT, an effect mediated by presynaptic 5-HT1B receptors. 4. In conclusion, serotonergic caudal raphe neurons are spontaneously active in vitro; they receive prominent glutamatergic synaptic inputs. 5-Hydroxytryptamine regulates serotonergic neuronal activity of the caudal raphe by decreasing spontaneous activity via somatodendritic 5-HT1A receptors and by inhibiting excitatory synaptic transmission onto these neurons via presynaptic 5-HT1B receptors. These local modulatory mechanisms provide multiple levels of feedback autoregulation of serotonergic raphe neurons by 5-HT.

Diurnal inhibition of NMDA-EPSCs at rat hippocampal mossy fibre synapses through orexin-2 receptors

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Perin, Martina; Longordo, Fabio; Massonnet, Christine; Welker, Egbert; Lüthi, Anita

2014-01-01

Diurnal release of the orexin neuropeptides orexin-A (Ox-A, hypocretin-1) and orexin-B (Ox-B, hypocretin-2) stabilises arousal, regulates energy homeostasis and contributes to cognition and learning. However, whether cellular correlates of brain plasticity are regulated through orexins, and whether they do so in a time-of-day-dependent manner, has never been assessed. Immunohistochemically we found sparse but widespread innervation of hippocampal subfields through Ox-A- and Ox-B-containing fibres in young adult rats. The actions of Ox-A were studied on NMDA receptor (NMDAR)-mediated excitatory synaptic transmission in acute hippocampal slices prepared around the trough (Zeitgeber time (ZT) 4–8, corresponding to 4–8 h into the resting phase) and peak (ZT 23) of intracerebroventricular orexin levels. At ZT 4–8, exogenous Ox-A (100 nm in bath) inhibited NMDA receptor-mediated excitatory postsynaptic currents (NMDA-EPSCs) at mossy fibre (MF)–CA3 (to 55.6 ± 6.8% of control, P = 0.0003) and at Schaffer collateral–CA1 synapses (70.8 ± 6.3%, P = 0.013), whereas it remained ineffective at non-MF excitatory synapses in CA3. Ox-A actions were mediated postsynaptically and blocked by the orexin-2 receptor (OX2R) antagonist JNJ10397049 (1 μm), but not by orexin-1 receptor inhibition (SB334867, 1 μm) or by adrenergic and cholinergic antagonists. At ZT 23, inhibitory effects of exogenous Ox-A were absent (97.6 ± 2.9%, P = 0.42), but reinstated (87.2 ± 3.3%, P = 0.002) when endogenous orexin signalling was attenuated for 5 h through i.p. injections of almorexant (100 mg kg−1), a dual orexin receptor antagonist. In conclusion, endogenous orexins modulate hippocampal NMDAR function in a time-of-day-dependent manner, suggesting that they may influence cellular plasticity and consequent variations in memory performance across the sleep–wake cycle. PMID:25085886

Spontaneous mutation by mutagenic repair of spontaneous lesions in DNA

International Nuclear Information System (INIS)

Hastings, P.J.; Quah, S.-K.; Borstel, R.C. von

1976-01-01

It is stated that strains of yeast carrying mutations in many of the steps in pathways repairing radiation-induced damage to DNA have enhanced spontaneous mutation rates. Most strains isolated because they have enhanced spontaneous mutation carry mutations in DNA repair systems. This suggests that much spontaneous mutation arises by mutagenic repair of spontaneous lesions. (author)

Salsolinol facilitates glutamatergic transmission to dopamine neurons in the posterior ventral tegmental area of rats.

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Guiqin Xie

Full Text Available Although in vivo evidence indicates that salsolinol, the condensation product of acetaldehyde and dopamine, has properties that may contribute to alcohol abuse, the underlying mechanisms have not been fully elucidated. We have reported previously that salsolinol stimulates dopamine neurons in the posterior ventral tegmental area (p-VTA partly by reducing inhibitory GABAergic transmission, and that ethanol increases glutamatergic transmission to VTA-dopamine neurons via the activation of dopamine D(1 receptors (D(1Rs. In this study, we tested the hypothesis that salsolinol stimulates dopamine neurons involving activation of D(1Rs. By using whole-cell recordings on p-VTA-dopamine neurons in acute brain slices of rats, we found that salsolinol-induced increase in spike frequency of dopamine neurons was substantially attenuated by DL-2-amino-5-phosphono-valeric acid and 6, 7-dinitroquinoxaline-2, 3-dione, the antagonists of glutamatergic N-Methyl-D-aspartic acid and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors. Moreover, salsolinol increased the amplitude of evoked excitatory postsynaptic currents (EPSCs and the frequency but not the amplitude of spontaneous EPSCs. Additionally, SKF83566, a D(1R antagonist attenuated the salsolinol-induced facilitation of EPSCs and of spontaneous firing of dopamine neurons. Our data reveal that salsolinol enhances glutamatergic transmission onto dopamine neurons via activation of D(1Rs at the glutamatergic afferents in dopamine neurons, which contributes to salsolinol's stimulating effect on p-VTA dopamine neurons. This appears to be a novel mechanism which contributes toward rewarding properties of salsolinol.

Roles of molecular layer interneurons in sensory information processing in mouse cerebellar cortex Crus II in vivo.

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Chun-Ping Chu

Full Text Available Cerebellar cortical molecular layer interneurons (MLIs play essential roles in sensory information processing by the cerebellar cortex. However, recent experimental and modeling results are questioning traditional roles for molecular layer inhibition in the cerebellum.Synaptic responses of MLIs and Purkinje cells (PCs, evoked by air-puff stimulation of the ipsilateral whisker pad were recorded from cerebellar cortex Crus II in urethane-anesthetized ICR mice by in vivo whole-cell patch-clamp recording techniques. Under current-clamp (I = 0, air-puff stimuli were found to primarily produce inhibition in PCs. In MLIs, this stimulus evoked spike firing regardless of whether they made basket-type synaptic connections or not. However, MLIs not making basket-type synaptic connections had higher rates of background activity and also generated spontaneous spike-lets. Under voltage-clamp conditions, excitatory postsynaptic currents (EPSCs were recorded in MLIs, although the predominant response of recorded PCs was an inhibitory postsynaptic potential (IPSP. The latencies of EPSCs were similar for all MLIs, but the time course and amplitude of EPSCs varied with depth in the molecular layer. The highest amplitude, shortest duration EPSCs were recorded from MLIs deep in the molecular layer, which also made basket-type synaptic connections. Comparing MLI to PC responses, time to peak of PC IPSP was significantly slower than MLI recorded EPSCs. Blocking GABA(A receptors uncovered larger EPSCs in PCs whose time to peak, half-width and 10-90% rising time were also significantly slower than in MLIs. Biocytin labeling indicated that the MLIs (but not PCs are dye-coupled.These findings indicate that tactile face stimulation evokes rapid excitation in MLIs and inhibition occurring at later latencies in PCs in mouse cerebellar cortex Crus II. These results support previous suggestions that the lack of parallel fiber driven PC activity is due to the effect

Does Spontaneous Favorability to Power (vs. Universalism) Values Predict Spontaneous Prejudice and Discrimination?

Science.gov (United States)

Souchon, Nicolas; Maio, Gregory R; Hanel, Paul H P; Bardin, Brigitte

2017-10-01

We conducted five studies testing whether an implicit measure of favorability toward power over universalism values predicts spontaneous prejudice and discrimination. Studies 1 (N = 192) and 2 (N = 86) examined correlations between spontaneous favorability toward power (vs. universalism) values, achievement (vs. benevolence) values, and a spontaneous measure of prejudice toward ethnic minorities. Study 3 (N = 159) tested whether conditioning participants to associate power values with positive adjectives and universalism values with negative adjectives (or inversely) affects spontaneous prejudice. Study 4 (N = 95) tested whether decision bias toward female handball players could be predicted by spontaneous attitude toward power (vs. universalism) values. Study 5 (N = 123) examined correlations between spontaneous attitude toward power (vs. universalism) values, spontaneous importance toward power (vs. universalism) values, and spontaneous prejudice toward Black African people. Spontaneous positivity toward power (vs. universalism) values was associated with spontaneous negativity toward minorities and predicted gender bias in a decision task, whereas the explicit measures did not. These results indicate that the implicit assessment of evaluative responses attached to human values helps to model value-attitude-behavior relations. © 2016 The Authors. Journal of Personality Published by Wiley Periodicals, Inc.

Galantamine Prevents Long-Lasting Suppression of Excitatory Synaptic Transmission in CA1 Pyramidal Neurons of Soman-Challenged Guinea Pigs

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Alexandrova, E. A.; Alkondon, M.; Aracava, Y.; Pereira, E. F. R.; Albuquerque, E. X.

2014-01-01

Galantamine, a drug currently approved for treatment of Alzheimer's disease, has recently emerged as an effective pretreatment against the acute toxicity and delayed cognitive deficits induced by organophosphorus (OP) nerve agents, including soman. Since cognitive deficits can result from impaired glutamatergic transmission in the hippocampus, the present study was designed to test the hypothesis that hippocampal glutamatergic transmission declines following an acute exposure to soman and that this effect can be prevented by galantamine. To test this hypothesis, spontaneous excitatory postsynaptic currents (EPSCs) were recorded from CA1 pyramidal neurons in hippocampal slices obtained at 1 h, 24 h, or 6-9 days after guinea pigs were injected with: (i) 1xLD50 soman (26.3 μg/kg, s.c.); (ii) galantamine (8 mg/kg, i.m.) followed 30 min later by 1xLD50 soman, (iii) galantamine (8 mg/kg, i.m.), or (iv) saline (0.5 ml/kg, i.m.). In soman-injected guinea pigs that were not pretreated with galantamine, the frequency of EPSCs was significantly lower than that recorded from saline-injected animals. There was no correlation between the severity of soman-induced acute toxicity and the magnitude of soman-induced reduction of EPSC frequency. Pretreatment with galantamine prevented the reduction of EPSC frequency observed at 6-9 days after the soman challenge. Prevention of soman-induced long-lasting reduction of hippocampal glutamatergic synaptic transmission may be an important determinant of the ability of galantamine to counter cognitive deficits that develop long after an acute exposure to the nerve agent. PMID:25064080

Spontaneous acute spinal subdural hematoma: spontaneous recovery from severe paraparesis--case report and review.

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Payer, Michael; Agosti, Reto

2010-11-01

Spontaneous idiopathic acute spinal subdural hematomas are highly exceptional. Neurological symptoms are usually severe, and rapid diagnosis with MRI is mandatory. Surgical evacuation has frequently been used therapeutically; however, spontaneous recovery in mild cases has also been reported. We present a case of spontaneous recovery from severe paraparesis after spontaneous acute SSDH, and review the English-speaking literature.

Spontaneous external gallbladder perforation

International Nuclear Information System (INIS)

Noeldge, G.; Wimmer, B.; Kirchner, R.

1981-01-01

Spontaneous perforation of the gallbladder is one complication of cholelithiasis. There is a greater occurence of free perforation in the peritoneal cavity with bilary pertonitis, followed by the perforation into the stomach, small intestine and colon. A single case of the nowadays rare spontaneous perforation in and through the abdominal wall will be reported. Spontaneous gallbladder perforation appears nearly asymptomatic in its clinical course because of absent biliary peritonitis. (orig.) [de

Hypocretin (orexin) regulates glutamate input to fast-spiking interneurons in layer V of the Fr2 region of the murine prefrontal cortex.

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Aracri, Patrizia; Banfi, Daniele; Pasini, Maria Enrica; Amadeo, Alida; Becchetti, Andrea

2015-05-01

We studied the effect of hypocretin 1 (orexin A) in the frontal area 2 (Fr2) of the murine neocortex, implicated in the motivation-dependent goal-directed tasks. In layer V, hypocretin stimulated the spontaneous excitatory postsynaptic currents (EPSCs) on fast-spiking (FS) interneurons. The effect was accompanied by increased frequency of miniature EPSCs, indicating that hypocretin can target the glutamatergic terminals. Moreover, hypocretin stimulated the spontaneous inhibitory postsynaptic currents (IPSCs) on pyramidal neurons, with no effect on miniature IPSCs. This action was prevented by blocking 1) the ionotropic glutamatergic receptors; 2) the hypocretin receptor type 1 (HCRTR-1), with SB-334867. Finally, hypocretin increased the firing frequency in FS cells, and the effect was blocked when the ionotropic glutamate transmission was inhibited. Immunolocalization confirmed that HCRTR-1 is highly expressed in Fr2, particularly in layer V-VI. Conspicuous labeling was observed in pyramidal neuron somata and in VGLUT1+ glutamatergic terminals, but not in VGLUT2+ fibers (mainly thalamocortical afferents). The expression of HCRTR-1 in GABAergic structures was scarce. We conclude that 1) hypocretin regulates glutamate release in Fr2; 2) the effect presents a presynaptic component; 3) the peptide control of FS cells is indirect, and probably mediated by the regulation of glutamatergic input onto these cells. © The Author 2013. Published by Oxford University Press.

Definition of spontaneous reconnection

International Nuclear Information System (INIS)

Schindler, K.

1984-01-01

The author discusses his view of driven versus spontaneous. There is a close link between ''spontaneous'' and ''instability.'' One of the prominent examples for instability is the thermal convection instability. Just to remind you, if you heat a fluid layer from below, it takes a certain Rayleigh number to make it unstable. Beyond the onset point you find qualitatively new features. That is called ''spontaneous,'' and this is a bit more than semantics. It's a new qualitative property that appears and it is spontaneous although we have an energy flux through the system. It's a misconception, to call this ''driven'' pointing at the energy flux through it. Of course, the convection would not exist without this energy flux. But what makes it ''spontaneous'' is that without any particular external signal, a new qualitative feature appears. And this is what is called an ''instability'' and ''spontaneous.'' From these considerations the author got a little reassured of what distinction should be made in the field of the magnetosphere. If we have a smooth energy transport into the magnetosphere and suddenly we have this qualitatively new feature (change of B-topology) coming up; then, using this terminology we don't have a choice other than calling this spontaneous or unstable, if you like. If we ''tell'' the system where it should make its neutral line and where it should make its plasmoids, then, it is driven. And this provides a very clear-cut observational distinction. The author emphasizes the difference he sees is a qualitative difference, not only a quantitative one

Spontaneous intracranial hypotension.

LENUS (Irish Health Repository)

Fullam, L

2012-01-31

INTRODUCTION: Spontaneous\\/primary intracranial hypotension is characterised by orthostatic headache and is associated with characteristic magnetic resonance imaging findings. CASE REPORT: We present a case report of a patient with typical symptoms and classical radiological images. DISCUSSION: Spontaneous intracranial hypotension is an under-recognised cause of headache and can be diagnosed by history of typical orthostatic headache and findings on MRI brain.

Effects of 17beta-estradiol on glutamate synaptic transmission and neuronal excitability in the rat medial vestibular nuclei.

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Grassi, S; Frondaroli, A; Scarduzio, M; Dutia, M B; Dieni, C; Pettorossi, V E

2010-02-17

We investigated the effects of the neurosteroid 17beta-estradiol (E(2)) on the evoked and spontaneous activity of rat medial vestibular nucleus (MVN) neurons in brainstem slices. E(2) enhances the synaptic response to vestibular nerve stimulation in type B neurons and depresses the spontaneous discharge in both type A and B neurons. The amplitude of the field potential, as well as the excitatory post-synaptic potential (EPSP) and current (EPSC), in type B neurons, are enhanced by E(2). Both effects are long-term phenomena since they outlast the drug washout. The enhancement of synaptic response is mainly due to facilitation of glutamate release mediated by pre-synaptic N-methyl-D-aspartate receptors (NMDARs), since the reduction of paired pulse ratio (PPR) and the increase of miniature EPSC frequency after E(2) are abolished under D-(-)-2-amino-5-phosphonopentanoic acid (AP-5). E(2) also facilitates post-synaptic NMDARs, but it does not affect directly alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) and group I-metabotropic glutamate receptors (mGluRs-I). In contrast, the depression of the spontaneous discharge of type A and type B neurons appears to depend on E(2) modulation of intrinsic ion conductances, as the effect remains after blockade of glutamate, GABA and glycine receptors (GlyRs). The net effect of E(2) is to enhance the signal-to-noise ratio of the synaptic response in type B neurons, relative to resting activity of all MVN neurons. These findings provide evidence for a novel potential mechanism to modulate the responsiveness of vestibular neurons to afferent inputs, and so regulate vestibular function in vivo.

Overexpression of cypin alters dendrite morphology, single neuron activity, and network properties via distinct mechanisms

Science.gov (United States)

Rodríguez, Ana R.; O'Neill, Kate M.; Swiatkowski, Przemyslaw; Patel, Mihir V.; Firestein, Bonnie L.

2018-02-01

Objective. This study investigates the effect that overexpression of cytosolic PSD-95 interactor (cypin), a regulator of synaptic PSD-95 protein localization and a core regulator of dendrite branching, exerts on the electrical activity of rat hippocampal neurons and networks. Approach. We cultured rat hippocampal neurons and used lipid-mediated transfection and lentiviral gene transfer to achieve high levels of cypin or cypin mutant (cypinΔPDZ PSD-95 non-binding) expression cellularly and network-wide, respectively. Main results. Our analysis revealed that although overexpression of cypin and cypinΔPDZ increase dendrite numbers and decrease spine density, cypin and cypinΔPDZ distinctly regulate neuronal activity. At the single cell level, cypin promotes decreases in bursting activity while cypinΔPDZ reduces sEPSC frequency and further decreases bursting compared to cypin. At the network level, by using the Fano factor as a measure of spike count variability, cypin overexpression results in an increase in variability of spike count, and this effect is abolished when cypin cannot bind PSD-95. This variability is also dependent on baseline activity levels and on mean spike rate over time. Finally, our spike sorting data show that overexpression of cypin results in a more complex distribution of spike waveforms and that binding to PSD-95 is essential for this complexity. Significance. Our data suggest that dendrite morphology does not play a major role in cypin action on electrical activity.

Preventing effect of L-type calcium channel blockade on electrophysiological alterations in dentate gyrus granule cells induced by entorhinal amyloid pathology.

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Hamid Gholami Pourbadie

Full Text Available The entorhinal cortex (EC is one of the earliest affected brain regions in Alzheimer's disease (AD. EC-amyloid pathology induces synaptic failure in the dentate gyrus (DG with resultant behavioral impairment, but there is little known about its impact on neuronal properties in the DG. It is believed that calcium dyshomeostasis plays a pivotal role in the etiology of AD. Here, the effect of the EC amyloid pathogenesis on cellular properties of DG granule cells and also possible neuroprotective role of L-type calcium channel blockers (CCBs, nimodipine and isradipine, were investigated. The amyloid beta (Aβ 1-42 was injected bilaterally into the EC of male rats and one week later, electrophysiological properties of DG granule cells were assessed. Voltage clamp recording revealed appearance of giant sIPSC in combination with a decrease in sEPSC frequency which was partially reversed by CCBs in granule cells from Aβ treated rats. EC amyloid pathogenesis induced a significant reduction of input resistance (Rin accompanied by a profound decreased excitability in the DG granule cells. However, daily administration of CCBs, isradipine or nimodipine (i.c.v. for 6 days, almost preserved the normal excitability against Aβ. In conclusion, lower tendency to fire AP along with reduced Rin suggest that DG granule cells might undergo an alteration in the membrane ion channel activities which finally lead to the behavioral deficits observed in animal models and patients with early-stage Alzheimer's disease.

[Spontaneous bacterial peritonitis].

Science.gov (United States)

Velkey, Bálint; Vitális, Eszter; Vitális, Zsuzsanna

2017-01-01

Spontaneous bacterial peritonitis occurs most commonly in cirrhotic patients with ascites. Pathogens get into the circulation by intestinal translocation and colonize in peritoneal fluid. Diagnosis of spontaneous bacterial peritonitis is based on elevated polymorphonuclear leukocyte count in the ascites (>0,25 G/L). Ascites culture is often negative but aids to get information about antibiotic sensitivity in positive cases. Treatment in stable patient can be intravenous then orally administrated ciprofloxacin or amoxicillin/clavulanic acid, while in severe cases intravenous III. generation cephalosporin. Nosocomial spontaneous bacterial peritonitis often caused by Gram-positive bacteria and multi-resistant pathogens can also be expected thus carbapenem should be the choice of the empiric treatment. Antibiotic prophylaxis should be considered. Norfloxacin is used most commonly, but changes are expected due to increase in quinolone resistance. As a primary prophylaxis, a short-term antibiotic treatment is recommended after gastrointestinal bleeding for 5 days, while long-term prophylaxis is for patients with low ascites protein, and advanced disease (400 mg/day). Secondary prophylaxis is recommended for all patients recovered from spontaneous bacterial peritonitis. Due to increasing antibiotic use of antibiotics prophylaxis is debated to some degree. Orv. Hetil., 2017, 158(2), 50-57.

Genetics Home Reference: primary spontaneous pneumothorax

Science.gov (United States)

... Home Health Conditions Primary spontaneous pneumothorax Primary spontaneous pneumothorax Printable PDF Open All Close All Enable Javascript ... view the expand/collapse boxes. Description Primary spontaneous pneumothorax is an abnormal accumulation of air in the ...

Soluble ICAM-5, a product of activity dependent proteolysis, increases mEPSC frequency and dendritic expression of GluA1.

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Irina Lonskaya

Full Text Available Matrix metalloproteinases (MMPs are zinc dependent endopeptidases that can be released from neurons in an activity dependent manner to play a role in varied forms of learning and memory. MMP inhibitors impair hippocampal long term potentiation (LTP, spatial memory, and behavioral correlates of drug addiction. Since MMPs are thought to influence LTP through a β1 integrin dependent mechanism, it has been suggested that these enzymes cleave specific substrates to generate integrin binding ligands. In previously published work, we have shown that neuronal activity stimulates rapid MMP dependent shedding of intercellular adhesion molecule-5 (ICAM-5, a synaptic adhesion molecule expressed on dendrites of the telencephalon. We have also shown that the ICAM-5 ectodomain can interact with β1 integrins to stimulate integrin dependent phosphorylation of cofilin, an event that occurs with dendritic spine maturation and LTP. In the current study, we investigate the potential for the ICAM-5 ectodomain to stimulate changes in α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptor (AMPAR dependent glutamatergic transmission. Single cell recordings show that the ICAM-5 ectodomain stimulates an increase in the frequency, but not the amplitude, of AMPA mini excitatory post synaptic currents (mEPSCs. With biotinylation and precipitation assays, we also show that the ICAM-5 ectodomain stimulates an increase in membrane levels of GluA1, but not GluA2, AMPAR subunits. In addition, we observe an ICAM-5 associated increase in GluA1 phosphorylation at serine 845. Concomitantly, ICAM-5 affects an increase in GluA1 surface staining along dendrites without affecting an increase in dendritic spine number. Together these data are consistent with the possibility that soluble ICAM-5 increases glutamatergic transmission and that post-synaptic changes, including increased phosphorylation and dendritic insertion of GluA1, could contribute. We suggest that future studies

Ziprasidone-induced spontaneous orgasm.

Science.gov (United States)

Boora, K; Chiappone, K; Dubovsky, S; Xu, J

2010-06-01

Neuroleptic treatment in schizophrenic patients has been associated with sexual dysfunction, including impotence and decreased libido. Spontaneous ejaculation without sexual arousal during typical antipsychotic treatment is a rare condition that has been described with zuclopentixol, trifluoperazine, and thiothixene. Here, we are reporting a case of spontaneous orgasm with ziprasidone in a bipolar patient. This patient began to repeatedly experience spontaneous sexual arousal and orgasm, which she had never experienced in the past. Ziprasidone might be causing an increase in sexual orgasm by 5-HT2 receptor antagonism, which preclinical evidence suggests that it facilitates dopamine release in the cortex.

Spontaneous rib fractures.

Science.gov (United States)

Katrancioglu, Ozgur; Akkas, Yucel; Arslan, Sulhattin; Sahin, Ekber

2015-07-01

Other than trauma, rib fracture can occur spontaneously due to a severe cough or sneeze. In this study, patients with spontaneous rib fractures were analyzed according to age, sex, underlying pathology, treatment, and complications. Twelve patients who presented between February 2009 and February 2011 with spontaneous rib fracture were reviewed retrospectively. The patients' data were evaluated according to anamnesis, physical examination, and chest radiographs. The ages of the patients ranged from 34 to 77 years (mean 55.91 ± 12.20 years), and 7 (58.4%) were male. All patients had severe cough and chest pain. The fractures were most frequently between 4th and 9th ribs; multiple rib fractures were detected in 5 (41.7%) patients. Eight (66.7%) patients had chronic obstructive pulmonary disease, 2 (16.7%) had bronchial asthma, and 2 (16.7%) had osteoporosis. Bone densitometry revealed a high risk of bone fracture in all patients. Patients with chronic obstructive pulmonary disease or bronchial asthma had been treated with high-dose steroids for over a year. Spontaneous rib fracture due to severe cough may occur in patients with osteoporosis, chronic obstructive pulmonary disease, or bronchial asthma, receiving long-term steroid therapy. If these patients have severe chest pain, chest radiography should be performed to check for bone lesions. © The Author(s) 2015.

Modified echo peak correction for radial acquisition regime (RADAR).

Science.gov (United States)

Takizawa, Masahiro; Ito, Taeko; Itagaki, Hiroyuki; Takahashi, Tetsuhiko; Shimizu, Kanichirou; Harada, Junta

2009-01-01

Because radial sampling imposes many limitations on magnetic resonance (MR) imaging hardware, such as on the accuracy of the gradient magnetic field or the homogeneity of B(0), some correction of the echo signal is usually needed before image reconstruction. In our previous study, we developed an echo-peak-shift correction (EPSC) algorithm not easily affected by hardware performance. However, some artifacts remained in lung imaging, where tissue is almost absent, or in cardiac imaging, which is affected by blood flow. In this study, we modified the EPSC algorithm to improve the image quality of the radial aquisition regime (RADAR) and expand its application sequences. We assumed the artifacts were mainly caused by errors in the phase map for EPSC and used a phantom on a 1.5-tesla (T) MR scanner to investigate whether to modify the EPSC algorithm. To evaluate the effectiveness of EPSC, we compared results from T(1)- and T(2)-weighted images of a volunteer's lung region using the current and modified EPSC. We then applied the modified EPSC to RADAR spin echo (SE) and RADAR balanced steady-state acquisition with rewound gradient echo (BASG) sequence. The modified EPSC reduced phase discontinuity in the reference data used for EPSC and improved visualization of blood vessels in the lungs. Motion and blood flow caused no visible artifacts in the resulting images in either RADAR SE or RADAR BASG sequence. Use of the modified EPSC eliminated artifacts caused by signal loss in the reference data for EPSC. In addition, the modified EPSC was applied to RADAR SE and RADAR BASG sequences.

Modified echo peak correction for radial acquisition regime (RADAR)

International Nuclear Information System (INIS)

Takizawa, Masahiro; Ito, Taeko; Itagaki, Hiroyuki; Takahashi, Tetsuhiko; Shimizu, Kanichirou; Harada, Junta

2009-01-01

Because radial sampling imposes many limitations on magnetic resonance (MR) imaging hardware, such as on the accuracy of the gradient magnetic field or the homogeneity of B 0 , some correction of the echo signal is usually needed before image reconstruction. In our previous study, we developed an echo-peak-shift correction (EPSC) algorithm not easily affected by hardware performance. However, some artifacts remained in lung imaging, where tissue is almost absent, or in cardiac imaging, which is affected by blood flow. In this study, we modified the EPSC algorithm to improve the image quality of the radial acquisition regime (RADAR) and expand its application sequences. We assumed the artifacts were mainly caused by errors in the phase map for EPSC and used a phantom on a 1.5-tesla (T) MR scanner to investigate whether to modify the EPSC algorithm. To evaluate the effectiveness of EPSC, we compared results from T 1 -and T 2 -weighted images of a volunteer's lung region using the current and modified EPSC. We then applied the modified EPSC to RADAR spin echo (SE) and RADAR balanced steady-state acquisition with rewound gradient echo (BASG) sequence. The modified EPSC reduced phase discontinuity in the reference data used for EPSC and improved visualization of blood vessels in the lungs. Motion and blood flow caused no visible artifacts in the resulting images in either RADAR SE or RADAR BASG sequence. Use of the modified EPSC eliminated artifacts caused by signal loss in the reference data for EPSC. In addition, the modified EPSC was applied to RADAR SE and RADAR BASG sequences. (author)

Spontaneous tension haemopneumothorax.

Science.gov (United States)

Patterson, Benjamin Oliver; Itam, Sarah; Probst, Fey

2008-10-31

We present a patient with sudden onset progressive shortness of breath and no history of trauma, who rapidly became haemodynamically compromised with a pneumothorax and pleural effusion seen on chest radiograph. He was treated for spontaneous tension pneumothorax but this was soon revealed to be a tension haemopneumothorax. He underwent urgent thoracotomy after persistent bleeding to explore an apical vascular abnormality seen on CT scanning. To our knowledge this is the first such case reported.Aetiology and current approach to spontaneous haemothorax are discussed briefly.

Visual patch clamp recording of neurons in thick portions of the adult spinal cord

DEFF Research Database (Denmark)

Munch, Anders Sonne; Smith, Morten; Moldovan, Mihai

2010-01-01

The study of visually identified neurons in slice preparations from the central nervous system offers considerable advantages over in vivo preparations including high mechanical stability in the absence of anaesthesia and full control of the extracellular medium. However, because of their relative...... remain alive and capable of generating action potentials. By stimulating the lateral funiculus we can evoke intense synaptic activity associated with large increases in conductance of the recorded neurons. The conductance increases substantially more in neurons recorded in thick slices suggesting...... that the size of the network recruited with the stimulation increases with the thickness of the slices. We also find that that the number of spontaneous excitatory postsynaptic currents (EPSCs) is higher in thick slices compared with thin slices while the number of spontaneous inhibitory postsynaptic currents...

Spontaneous tension haemopneumothorax

Directory of Open Access Journals (Sweden)

Itam Sarah

2008-10-01

Full Text Available Abstract We present a patient with sudden onset progressive shortness of breath and no history of trauma, who rapidly became haemodynamically compromised with a pneumothorax and pleural effusion seen on chest radiograph. He was treated for spontaneous tension pneumothorax but this was soon revealed to be a tension haemopneumothorax. He underwent urgent thoracotomy after persistent bleeding to explore an apical vascular abnormality seen on CT scanning. To our knowledge this is the first such case reported. Aetiology and current approach to spontaneous haemothorax are discussed briefly.

Spontaneous compactification to homogeneous spaces

International Nuclear Information System (INIS)

Mourao, J.M.

1988-01-01

The spontaneous compactification of extra dimensions to compact homogeneous spaces is studied. The methods developed within the framework of coset space dimensional reduction scheme and the most general form of invariant metrics are used to find solutions of spontaneous compactification equations

Case of spontaneous ventriculocisternostomy

Energy Technology Data Exchange (ETDEWEB)

Yamane, Kanji; Yoshimoto, Hisanori; Harada, Kiyoshi; Uozumi, Tohru [Hiroshima Univ. (Japan). School of Medicine; Kuwabara, Satoshi

1983-05-01

The authors experienced a case of spontaneous ventriculocisternostomy diagnosed by CT scan with metrizamide and Conray. Patient was 23-year-old male who had been in good health until one month before admission, when he began to have headache and tinnitus. He noticed bilateral visual acuity was decreased about one week before admission and vomiting appeared two days before admission. He was admitted to our hospital because of bilateral papilledema and remarkable hydrocephalus diagnosed by CT scan. On admission, no abnormal neurological signs except for bilateral papilledema were noted. Immediately, right ventricular drainage was performed. Pressure of the ventricle was over 300mmH/sub 2/O and CSF was clear. PVG and PEG disclosed an another cavity behind the third ventricle, which was communicated with the third ventricle, and occlusion of aqueduct of Sylvius. Metrizamide CT scan and Conray CT scan showed a communication between this cavity and quadrigeminal and supracerebellar cisterns. On these neuroradiological findings, the diagnosis of obstructive hydrocephalus due to benign aqueduct stenosis accompanied with spontaneous ventriculocisternostomy was obtained. Spontaneous ventriculocisternostomy was noticed to produce arrest of hydrocephalus, but with our case, spontaneous regression of such symptoms did not appeared. By surgical ventriculocisternostomy (method by Torkildsen, Dandy, or Scarff), arrest of hydrocephalus was seen in about 50 to 70 per cent, which was the same results as those of spontaneous ventriculocisternostomy. It is concluded that VP shunt or VA shunt is thought to be better treatment of obstructive hydrocephalus than the various kinds of surgical ventriculocisternostomy.

Spontaneous Intracranial Hypotension without Orthostatic Headache

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Tülay Kansu

2009-03-01

Full Text Available We report 2 cases of spontaneous intracranial hypotension that presented with unilateral abducens nerve palsy, without orthostatic headache. While sixth nerve palsies improved without any intervention, subdural hematoma was detected with magnetic resonance imaging. We conclude that headache may be absent in spontaneous intracranial hypotension and spontaneous improvement of sixth nerve palsy can occur, even after the development of a subdural hematoma

Spontaneous intraorbital hematoma: case report

Directory of Open Access Journals (Sweden)

Vinodan Paramanathan

2010-12-01

Full Text Available Vinodan Paramanathan, Ardalan ZolnourianQueen's Hospital NHS Foundation Trust, Burton on Trent, Staffordshire DE13 0RB, UKAbstract: Spontaneous intraorbital hematoma is an uncommon clinical entity seen in ophthalmology practice. It is poorly represented in the literature. Current evidence attributes it to orbital trauma, neoplasm, vascular malformations, acute sinusitis, and systemic abnormalities. A 65-year-old female presented with spontaneous intraorbital hematoma manifesting as severe ocular pains, eyelid edema, proptosis, and diplopia, without a history of trauma. Computer tomography demonstrated a fairly well defined extraconal lesion with opacification of the paranasal sinuses. The principal differential based on all findings was that of a spreading sinus infection and an extraconal tumor. An unprecedented finding of a spontaneous orbital hematoma was discovered when the patient was taken to theater. We discuss the rarity of this condition and its management.Keywords: hemorrhage, ophthalmology, spontaneous, intra-orbital, hematoma

Screening for spontaneous preterm birth

NARCIS (Netherlands)

van Os, M.A.; van Dam, A.J.E.M.

2015-01-01

Preterm birth is the most important cause of perinatal morbidity and mortality worldwide. In this thesis studies on spontaneous preterm birth are presented. The main objective was to investigate the predictive capacity of mid-trimester cervical length measurement for spontaneous preterm birth in a

Early pregnancy angiogenic markers and spontaneous abortion

DEFF Research Database (Denmark)

Andersen, Louise B; Dechend, Ralf; Karumanchi, S Ananth

2016-01-01

BACKGROUND: Spontaneous abortion is the most commonly observed adverse pregnancy outcome. The angiogenic factors soluble Fms-like kinase 1 and placental growth factor are critical for normal pregnancy and may be associated to spontaneous abortion. OBJECTIVE: We investigated the association between...... maternal serum concentrations of soluble Fms-like kinase 1 and placental growth factor, and subsequent spontaneous abortion. STUDY DESIGN: In the prospective observational Odense Child Cohort, 1676 pregnant women donated serum in early pregnancy, gestational week ..., interquartile range 71-103). Concentrations of soluble Fms-like kinase 1 and placental growth factor were determined with novel automated assays. Spontaneous abortion was defined as complete or incomplete spontaneous abortion, missed abortion, or blighted ovum

Spontaneous emission by moving atoms

International Nuclear Information System (INIS)

Meystre, P.; Wilkens, M.

1994-01-01

It is well known that spontaneous emission is not an intrinsic atomic property, but rather results from the coupling of the atom to the vacuum modes of the electromagnetic field. As such, it can be modified by tailoring the electromagnetic environment into which the atom can radiate. This was already realized by Purcell, who noted that the spontaneous emission rate can be enhanced if the atom placed inside a cavity is resonant with one of the cavity is resonant with one of the cavity modes, and by Kleppner, who discussed the opposite case of inhibited spontaneous emission. It has also been recognized that spontaneous emission need not be an irreversible process. Indeed, a system consisting of a single atom coupled to a single mode of the electromagnetic field undergoes a periodic exchange of excitation between the atom and the field. This periodic exchange remains dominant as long as the strength of the coupling between the atom and a cavity mode is itself dominant. 23 refs., 6 figs

A Case of Multiple Spontaneous Keloid Scars

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Abdulhadi Jfri

2015-07-01

Full Text Available Keloid scars result from an abnormal healing response to cutaneous injury or inflammation that extends beyond the borders of the original wound. Spontaneous keloid scars forming in the absence of any previous trauma or surgical procedure are rare. Certain syndromes have been associated with this phenomenon, and few reports have discussed the evidence of single spontaneous keloid scar, which raises the question whether they are really spontaneous. Here, we present a 27-year-old mentally retarded single female with orbital hypertelorism, broad nasal bridge, repaired cleft lip and high-arched palate who presented with progressive multiple spontaneous keloid scars in different parts of her body which were confirmed histologically by the presence of typical keloidal collagen. This report supports the fact that keloid scars can appear spontaneously and are possibly linked to a genetic factor. Furthermore, it describes a new presentation of spontaneous keloid scars in the form of multiple large lesions in different sites of the body.

Spontaneous pneumothorax in silicotuberculosis of lung

International Nuclear Information System (INIS)

Kolenic, J.; Jurgova, T.; Zimacek, J.; Vajo, J.; Krchnavy, M.

1995-01-01

The authors describe the case of 62 years old man with the appearance of spontaneous pneumothorax, in whom the basic pulmonary disease was silicotuberculosis of the lung. At clinic of occupational diseases in Kosice have been evidence 965 cases of silicosis and silicotuberculosis. From 1971 they have now the first case of spontaneous pneumothorax. The authors make discussion about possible mechanical and biochemical factors, which cause relatively low incidence of spontaneous pneumothorax in silicosis of the lung. (authors)

Spontaneous body movements in spatial cognition

Directory of Open Access Journals (Sweden)

Sergiu eTcaci Popescu

2012-05-01

Full Text Available People often perform spontaneous body movements during spatial tasks such as giving complex directions or orienting themselves on maps. How are these spontaneous gestures related to spatial problem-solving? We measured spontaneous movements during a perspective-taking task inspired by map reading. Analyzing the motion data to isolate rotation and translation components of motion in specific geometric relation to the task, we found out that most participants executed spontaneous miniature rotations of the head that were significantly related to the main task parameter. These head rotations were as if participants were trying to align themselves with the orientation on the map either in the image plane or on the ground plane, but with tiny amplitudes, typically below 1% of the actual movements. Our results are consistent with a model of sensorimotor prediction driving spatial reasoning. The efference copy of planned movements triggers this prediction mechanism. The movements themselves may then be mostly inhibited; the small spontaneous gestures that we measure are the visible traces of these planned but inhibited actions.

Spontaneous pneumothorax in diffuse cystic lung diseases.

Science.gov (United States)

Cooley, Joseph; Lee, Yun Chor Gary; Gupta, Nishant

2017-07-01

Diffuse cystic lung diseases (DCLDs) are a heterogeneous group of disorders with varying pathophysiologic mechanisms that are characterized by the presence of air-filled lung cysts. These cysts are prone to rupture, leading to the development of recurrent spontaneous pneumothoraces. In this article, we review the epidemiology, clinical features, and management DCLD-associated spontaneous pneumothorax, with a focus on lymphangioleiomyomatosis, Birt-Hogg-Dubé syndrome, and pulmonary Langerhans cell histiocytosis. DCLDs are responsible for approximately 10% of apparent primary spontaneous pneumothoraces. Computed tomography screening for DCLDs (Birt-Hogg-Dubé syndrome, lymphangioleiomyomatosis, and pulmonary Langerhans cell histiocytosis) following the first spontaneous pneumothorax has recently been shown to be cost-effective and can help facilitate early diagnosis of the underlying disorders. Patients with DCLD-associated spontaneous pneumothorax have a very high rate of recurrence, and thus pleurodesis should be considered following the first episode of spontaneous pneumothorax in these patients, rather than waiting for a recurrent episode. Prior pleurodesis is not a contraindication to future lung transplant. Although DCLDs are uncommon, spontaneous pneumothorax is often the sentinel event that provides an opportunity for diagnosis. By understanding the burden and implications of pneumothoraces in DCLDs, clinicians can facilitate early diagnosis and appropriate management of the underlying disorders.

FEL gain optimisation and spontaneous radiation

Energy Technology Data Exchange (ETDEWEB)

Bali, L.M.; Srivastava, A.; Pandya, T.P. [Lucknow Univ. (India)] [and others

1995-12-31

Colson have evaluated FEL gains for small deviations from perfect electron beam injection, with radiation of the same polarisation as that of the wiggler fields. We find that for optimum gain the polarisation of the optical field should be the same as that of the spontaneous emission under these conditions. With a helical wiggler the axial oscillations resulting from small departures from perfect electron beam injection lead to injection dependent unequal amplitudes and phases of the spontaneous radiation in the two transverse directions. Viewed along the axis therefore the spontaneous emission is elliptically polarised. The azimuth of the ellipse varies with the difference of phase of the two transverse components of spontaneous emission but the eccentricity remains the same. With planar wigglers the spontaneous emission viewed in the axial direction is linearly polarised, again with an injection dependent azimuth. For optimum coherent gain of a radiation field its polarisation characteristics must be the same as those of the spontaneous radiation with both types of wiggler. Thus, with a helical wiggler and the data reported earlier, an increase of 10% in the FEL gain at the fundamental frequency and of 11% at the fifth harmonic has been calculated in the small gain per pass limit. Larger enhancements in gain may result from more favourable values of input parameters.

Spontaneous Bacterial Peritonitis in Subclinical Hypothyroidism

Directory of Open Access Journals (Sweden)

Dalip Gupta

2013-11-01

Full Text Available Hypothyroidism is an uncommon cause of ascites. Here we describe a case of a 75 year-old female patient with spontaneous bacterial peritonitis and subclinical hypothyroidism that resolved with thyroid replacement and antibiotic therapy respectively. Ascitic fluid analysis revealed a gram-positive bacterium on gram staining. A review of the literature revealed just one other reported case of myxoedema ascites with concomitant spontaneous bacterial peritonitis and no case has till been reported of spontaneous bacterial peritonitis in subclinical hypothyroidism.

Spontaneous mutation rates and the rate-doubling dose

International Nuclear Information System (INIS)

Von Borstel, R.C.; Moustaccki, E.; Latarjet, R.

1978-01-01

The amount of radiation required to double the frequency of mutations or tumours over the rate of those that occur spontaneously is called the rate-doubling dose. An equivalent concept has been proposed for exposure to other environmental mutagens. The doubling dose concept is predicated on the assumption that all human populations have the same spontaneous mutation rate, and that this spontaneous mutation rate is known. It is now established for prokaryotes and lower eukaryotes that numerous genes control the spontaneous mutation rate, and it is likely that the same is true for human cells as well. Given that the accepted mode of evolution of human populatons is from small, isolated groups of individuals, it seems likely that each population would have a different spontaneous mutation rate. Given that a minimum of twenty genes control or affect the spontaneous mutation rate, and that each of these in turn is susceptible to spontaneously arising or environmentally induced mutations, it seems likely that every individual within a population (except for siblings from identical multiple births) will have a unique spontaneous mutation rate. If each individual in a population does have a different spontaneous mutation rate, the doubling dose concept, in rigorous terms, is fallacious. Therefore, as with other concepts of risk evaluation, the doubling dose concept is subject to criticism. Nevertheless, until we know individual spontaneous mutation rates with precision, and can evaluate risks based on this information, the doubling dose concept has a heuristic value and is needed for practical assessment of risks for defined populations. (author)

Visually Evoked Spiking Evolves While Spontaneous Ongoing Dynamics Persist

Science.gov (United States)

Huys, Raoul; Jirsa, Viktor K.; Darokhan, Ziauddin; Valentiniene, Sonata; Roland, Per E.

2016-01-01

Neurons in the primary visual cortex spontaneously spike even when there are no visual stimuli. It is unknown whether the spiking evoked by visual stimuli is just a modification of the spontaneous ongoing cortical spiking dynamics or whether the spontaneous spiking state disappears and is replaced by evoked spiking. This study of laminar recordings of spontaneous spiking and visually evoked spiking of neurons in the ferret primary visual cortex shows that the spiking dynamics does not change: the spontaneous spiking as well as evoked spiking is controlled by a stable and persisting fixed point attractor. Its existence guarantees that evoked spiking return to the spontaneous state. However, the spontaneous ongoing spiking state and the visual evoked spiking states are qualitatively different and are separated by a threshold (separatrix). The functional advantage of this organization is that it avoids the need for a system reorganization following visual stimulation, and impedes the transition of spontaneous spiking to evoked spiking and the propagation of spontaneous spiking from layer 4 to layers 2–3. PMID:26778982

Peritonitis - spontaneous bacterial

Science.gov (United States)

Spontaneous bacterial peritonitis (SBP); Ascites - peritonitis; Cirrhosis - peritonitis ... who are on peritoneal dialysis for kidney failure. Peritonitis may have other causes . These include infection from ...

Search for spontaneous fission of 226Ra and systematics of the spontaneous fission, α-decay and cluster decay probabilities

International Nuclear Information System (INIS)

Mikheev, V.L.; Tret'yakova, S.P.; Golovchenko, A.N.; Timofeeva, O.V.; Hussonnois, M.; Le Naour, C.

1998-01-01

The low limit of the 226 Ra spontaneous fission half-life corresponding to T 1/2 ≥ 4 · 10 18 years is measured. The 226 Ra spontaneous fission probability proved to be about 50 times less than the value expected from the known systematics, connecting the ratios of theα-decay and spontaneous fission probabilities with the fissility parameter Z 2 /A. It is shown that the probabilities of spontaneous fission, α-decay and cluster decay can be systematized in the same way according to the difference between the decay products Coulomb energy near the scission point and decay energy Q

Dorsomedial prefontal cortex supports spontaneous thinking per se.

Science.gov (United States)

Raij, T T; Riekki, T J J

2017-06-01

Spontaneous thinking, an action to produce, consider, integrate, and reason through mental representations, is central to our daily experience and has been suggested to serve crucial adaptive purposes. Such thinking occurs among other experiences during mind wandering that is associated with activation of the default mode network among other brain circuitries. Whether and how such brain activation is linked to the experience of spontaneous thinking per se remains poorly known. We studied 51 healthy subjects using a comprehensive experience-sampling paradigm during 3T functional magnetic resonance imaging. In comparison with fixation, the experiences of spontaneous thinking and spontaneous perception were related to activation of wide-spread brain circuitries, including the cortical midline structures, the anterior cingulate cortex and the visual cortex. In direct comparison of the spontaneous thinking versus spontaneous perception, activation was observed in the anterior dorsomedial prefrontal cortex. Modality congruence of spontaneous-experience-related brain activation was suggested by several findings, including association of the lingual gyrus with visual in comparison with non-verbal-non-visual thinking. In the context of current literature, these findings suggest that the cortical midline structures are involved in the integrative core substrate of spontaneous thinking that is coupled with other brain systems depending on the characteristics of thinking. Furthermore, involvement of the anterior dorsomedial prefrontal cortex suggests the control of high-order abstract functions to characterize spontaneous thinking per se. Hum Brain Mapp 38:3277-3288, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Maternal smoking predicts the risk of spontaneous abortion

DEFF Research Database (Denmark)

Nielsen, Ann; Hannibal, Charlotte Gerd; Lindekilde, Bodil Eriksen

2006-01-01

BACKGROUND: Few studies have examined smoking prior to pregnancy and the occurrence of spontaneous abortion, as most studies have addressed the risk of spontaneous abortion in relation to smoking during pregnancy. However, results are not entirely consistent. The aim of the present study...... was to assess the risk of spontaneous abortion considering smoking prior to pregnancy. METHODS: We performed a nested case-control study using prospective data from a population-based cohort comprising 11,088 women aged 20-29 years. From this cohort, women who experienced either a spontaneous abortion (n=343......) or who gave birth (n=1,578) during follow-up were selected. Associations between self-reported smoking at enrollment and subsequent spontaneous abortion were analyzed by means of multiple logistic regression. RESULTS: The risk of spontaneous abortion in relation to pre-pregnancy smoking showed a clear...

Osteonecrosis or spontaneous fractures following renal transplantation

International Nuclear Information System (INIS)

Andresen, J.; Nielsen, H.E.; Aarhus Univ.

1981-01-01

31 renal transplant recipients with posttransplant development of osteonecrosis or spontaneous fractures were evaluated with regard to age, duration of dialysis before transplantation. Determination of metacarpal bone mass at the time of transplantation and registration of bone resorption and soft tissue calcification at the time of transplantation and at the time of onset of osteonecrosis and spontaneous fractures were made. Apart from the increased mean age in patients with spontaneous fractures no difference was seen between the groups. Osteonecrosis and spontaneous fractures occurred in areas of trabecular bone. It seems most likely that after renal transplantation the patients show bone complications of different localization. (orig.) [de

A Case of Spontaneously Resolved Bilateral Primary Spontaneous Pneumothorax

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Hasan Kahraman

2014-03-01

Full Text Available A condition of intrapleural air-space accumulation in individuals without any history of trauma or lung disease is called as primary spontaneous pneumothorax (PSP. Sixteen-years-old male patient admitted with complains of chest pain and dyspnea beginning 3 day ago. On physical examination, severity of breath sounds decreased on right side. Chest radiograph was taken and right-sided pneumothorax was detected and tube thoracostomy was inserted. Two months ago the patient referred to a doctor with similar complaints and physical examination and chest radiograph were reported as normal. The radiograph was retrospectively examined and bilateral PSP was detected. We presented the case duo to spontaneous recovery of bilateral PSP is seen very rarely and so contributes data to the literature. In patients admitted to the clinic with chest pain and shortness of breath, pneumothorax should be considered at differential diagnosis.

Maternal underweight and the risk of spontaneous abortion

DEFF Research Database (Denmark)

Helgstrand, Stine; Andersen, Anne-Marie Nybo

2005-01-01

BACKGROUND: To evaluate the risk of spontaneous abortion in relation to maternal pre-pregnant underweight. METHODS: The study was designed as a cohort study within the framework of the Danish National Birth Cohort (DNBC). The participants were a total of 23 821 women recruited consecutively...... spontaneous abortion. Relative risk of spontaneous abortion was calculated as Hazard Ratios using Cox regression with delayed entry. RESULTS: The outcome measure was spontaneous abortion. The hazard ratio for spontaneous abortion in women with a pre-pregnant body mass index (BMI) below 18.5 was 1.24 (95......% confidence limits 0.95-1.63) compared to women with pre-pregnant BMI 18.5-24.9. Women with a BMI of 25 or more had a smaller increase in risk of spontaneous abortion. Adjustment for maternal age, parity, previous miscarriages, and lifestyle factors did not affect the estimates substantially, neither did...

Spontaneous deregulation

NARCIS (Netherlands)

Edelman, Benjamin; Geradin, Damien

Platform businesses such as Airbnb and Uber have risen to success partly by sidestepping laws and regulations that encumber their traditional competitors. Such rule flouting is what the authors call “spontaneous private deregulation,” and it’s happening in a growing number of industries. The authors

A case of spontaneous ventriculocisternostomy

International Nuclear Information System (INIS)

Yamane, Kanji; Yoshimoto, Hisanori; Harada, Kiyoshi; Uozumi, Tohru; Kuwabara, Satoshi.

1983-01-01

The authors experienced a case of spontaneous ventriculocisternostomy diagnosed by CT scan with metrizamide and Conray. Patient was 23-year-old male who had been in good health until one month before admission, when he began to have headache and tinnitus. He noticed bilateral visual acuity was decreased about one week before admission and vomiting appeared two days before admission. He was admitted to our hospital because of bilateral papilledema and remarkable hydrocephalus diagnosed by CT scan. On admission, no abnormal neurological signs except for bilateral papilledema were noted. Immediately, right ventricular drainage was performed. Pressure of the ventricle was over 300mmH 2 O and CSF was clear. PVG and PEG disclosed an another cavity behind the third ventricle, which was communicated with the third ventricle, and occlusion of aqueduct of Sylvius. Metrizamide CT scan and Conray CT scan showed a communication between this cavity and quadrigeminal and supracerebellar cisterns. On these neuroradiological findings, the diagnosis of obstructive hydrocephalus due to benign aqueduct stenosis accompanied with spontaneous ventriculocisternostomy was obtained. Spontaneous ventriculocisternostomy was noticed to produce arrest of hydrocephalus, but with our case, spontaneous regression of such symptoms did not appeared. By surgical ventriculocisternostomy (method by Torkildsen, Dandy, or Scarff), arrest of hydrocephalus was seen in about 50 to 70 per cent, which was the same results as those of spontaneous ventriculocisternostomy. It is concluded that VP shunt or VA shunt is thought to be better treatment of obstructive hydrocephalus than the various kinds of surgical ventriculocisternostomy. (J.P.N.)

Multivesicular release underlies short term synaptic potentiation independent of release probability change in the supraoptic nucleus.

Directory of Open Access Journals (Sweden)

Michelle E Quinlan

Full Text Available Magnocellular neurons of the supraoptic nucleus receive glutamatergic excitatory inputs that regulate the firing activity and hormone release from these neurons. A strong, brief activation of these excitatory inputs induces a lingering barrage of tetrodotoxin-resistant miniature EPSCs (mEPSCs that lasts for tens of minutes. This is known to accompany an immediate increase in large amplitude mEPSCs. However, it remains unknown how long this amplitude increase can last and whether it is simply a byproduct of greater release probability. Using in vitro patch clamp recording on acute rat brain slices, we found that a brief, high frequency stimulation (HFS of afferents induced a potentiation of mEPSC amplitude lasting up to 20 min. This amplitude potentiation did not correlate with changes in mEPSC frequency, suggesting that it does not reflect changes in presynaptic release probability. Nonetheless, neither postsynaptic calcium chelator nor the NMDA receptor antagonist blocked the potentiation. Together with the known calcium dependency of HFS-induced potentiation of mEPSCs, our results imply that mEPSC amplitude increase requires presynaptic calcium. Further analysis showed multimodal distribution of mEPSC amplitude, suggesting that large mEPSCs were due to multivesicular glutamate release, even at late post-HFS when the frequency is no longer elevated. In conclusion, high frequency activation of excitatory synapses induces lasting multivesicular release in the SON, which is independent of changes in release probability. This represents a novel form of synaptic plasticity that may contribute to prolonged excitatory tone necessary for generation of burst firing of magnocellular neurons.

Quantifying emissions from spontaneous combustion

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-09-01

Spontaneous combustion can be a significant problem in the coal industry, not only due to the obvious safety hazard and the potential loss of valuable assets, but also with respect to the release of gaseous pollutants, especially CO2, from uncontrolled coal fires. This report reviews methodologies for measuring emissions from spontaneous combustion and discusses methods for quantifying, estimating and accounting for the purpose of preparing emission inventories.

Spontaneous calf haematoma: case report.

Science.gov (United States)

Zubaidah, N H; Liew, N C

2014-02-01

Spontaneous calf haematoma is a rare condition and few case reports have been published in the English literature. Common conditions like deep vein thrombosis and traumatic gastrocnemius muscle tear need to be considered when a patient presents with unilateral calf swelling and tenderness. Ultrasound and Magnetic Resonance Imaging are essential for confirmation of diagnosis. The purpose of this paper is to report on a rare case of spontaneous calf hematoma and its diagnosis and management.

F. VON HAYEK’S THEORY OF SPONTANEOUS ORDER

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О. Nesterenko

2013-04-01

Full Text Available The essence and the genesis of spontaneous order are disclosed in the context of critical analysis of constructivism. The author’s approach to the definition of the characteristic features of the spontaneous order is proposed. The dichotomy of the order is revealed towards the economic sphere in form of spontaneous order and organization.

Spontaneous pneumomediastinum after bench press training.

Science.gov (United States)

Nishino, Tomoya

2017-04-01

Spontaneous pneumomediastinum is often associated with asthma and mainly affects adolescent males with a tall, thin body habitus. A 17-year-old man complained of chest and pharyngeal pain after bench press training and spontaneous pneumomediastinum was diagnosed. It should be considered in the differential diagnosis of chest pain of uncertain cause.

Spontaneous cooperation for prosocials, but not for proselfs: Social value orientation moderates spontaneous cooperation behavior

Science.gov (United States)

Mischkowski, Dorothee; Glöckner, Andreas

2016-01-01

Cooperation is essential for the success of societies and there is an ongoing debate whether individuals have therefore developed a general spontaneous tendency to cooperate or not. Findings that cooperative behavior is related to shorter decision times provide support for the spontaneous cooperation effect, although contrary results have also been reported. We show that cooperative behavior is better described as person × situation interaction, in that there is a spontaneous cooperation effect for prosocial but not for proself persons. In three studies, one involving population representative samples from the US and Germany, we found that cooperation in a public good game is dependent on an interaction between individuals’ social value orientation and decision time. Increasing deliberation about the dilemma situation does not affect persons that are selfish to begin with, but it is related to decreasing cooperation for prosocial persons that gain positive utility from outcomes of others and score high on the related general personality trait honesty/humility. Our results demonstrate that the spontaneous cooperation hypothesis has to be qualified in that it is limited to persons with a specific personality and social values. Furthermore, they allow reconciling conflicting previous findings by identifying an important moderator for the effect. PMID:26876773

Spontaneous ischaemic stroke in dogs

DEFF Research Database (Denmark)

Gredal, Hanne Birgit; Skerritt, G. C.; Gideon, P.

2013-01-01

Translation of experimental stroke research into the clinical setting is often unsuccessful. Novel approaches are therefore desirable. As humans, pet dogs suffer from spontaneous ischaemic stroke and may hence offer new ways of studying genuine stroke injury mechanisms.......Translation of experimental stroke research into the clinical setting is often unsuccessful. Novel approaches are therefore desirable. As humans, pet dogs suffer from spontaneous ischaemic stroke and may hence offer new ways of studying genuine stroke injury mechanisms....

Spontaneity and international marketing performance

OpenAIRE

Souchon, Anne L.; Hughes, Paul; Farrell, Andrew M.; Nemkova, Ekaterina; Oliveira, Joao S.

2016-01-01

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link. Purpose – The purpose of this paper is to ascertain how today’s international marketers can perform better on the global scene by harnessing spontaneity. Design/methodology/approach – The authors draw on contingency theory to develop a model of the spontaneity – international marketing performance relationship, and identify three potential m...

Analysis of the Spontaneous Abortion in Chinese Married Women

Institute of Scientific and Technical Information of China (English)

高尔生; 邓新清; 何更生; 方可娟; 唐威; 楼超华

1994-01-01

The spontaneous abortion is a common type of pregnant outcomes. The spontaneous abortion rate can be used to indicate the women's fecundity and the level of the reproductive health. It is also a sensitive indicator for determing the social, economic, and health status and prenatal care. To explore the preventive method for spontaneous abortion and improve women's health level, it is important to evaluate the status of spontaneous abortion and to determine the factors affecting

Spontaneous Vesicle Recycling in the Synaptic Bouton

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Sven eTruckenbrodt

2014-12-01

Full Text Available The trigger for synaptic vesicle exocytosis is Ca2+, which enters the synaptic bouton following action potential stimulation. However, spontaneous release of neurotransmitter also occurs in the absence of stimulation in virtually all synaptic boutons. It has long been thought that this represents exocytosis driven by fluctuations in local Ca2+ levels. The vesicles responding to these fluctuations are thought to be the same ones that release upon stimulation, albeit potentially triggered by different Ca2+ sensors. This view has been challenged by several recent works, which have suggested that spontaneous release is driven by a separate pool of synaptic vesicles. Numerous articles appeared during the last few years in support of each of these hypotheses, and it has been challenging to bring them into accord. We speculate here on the origins of this controversy, and propose a solution that is related to developmental effects. Constitutive membrane traffic, needed for the biogenesis of vesicles and synapses, is responsible for high levels of spontaneous membrane fusion in young neurons, probably independent of Ca2+. The vesicles releasing spontaneously in such neurons are not related to other synaptic vesicle pools and may represent constitutively releasing vesicles (CRVs rather than bona fide synaptic vesicles. In mature neurons, constitutive traffic is much dampened, and the few remaining spontaneous release events probably represent bona fide spontaneously releasing synaptic vesicles (SRSVs responding to Ca2+ fluctuations, along with a handful of CRVs that participate in synaptic vesicle turnover.

Spontaneous Atraumatic Mediastinal Hemorrhage

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Morkos Iskander BSc, BMBS, MRCS, PGCertMedEd

2013-04-01

Full Text Available Spontaneous atraumatic mediastinal hematomas are rare. We present a case of a previously fit and well middle-aged lady who presented with acute breathlessness and an increasing neck swelling and spontaneous neck bruising. On plain chest radiograph, widening of the mediastinum was noted. The bruising was later confirmed to be secondary to mediastinal hematoma. This life-threatening diagnostic conundrum was managed conservatively with a multidisciplinary team approach involving upper gastrointestinal and thoracic surgeons, gastroenterologists, radiologists, intensivists, and hematologists along with a variety of diagnostic modalities. A review of literature is also presented to help surgeons manage such challenging and complicated cases.

Spontaneous Retropharyngeal Emphysema: A Case Report | Chi ...

African Journals Online (AJOL)

... is a rare clinical condition in pediatric otolaryngology. The predominant symptoms are sore throat, odynophagia, dysphagia, and neck pain. Here, we report a case of spontaneous retropharyngeal emphysema. Keywords: Iatrogenic injury, retropharyngeal emphysema, spontaneous retropharyngeal emphysem, trauma ...

Spontaneous regression of pulmonary bullae

International Nuclear Information System (INIS)

Satoh, H.; Ishikawa, H.; Ohtsuka, M.; Sekizawa, K.

2002-01-01

The natural history of pulmonary bullae is often characterized by gradual, progressive enlargement. Spontaneous regression of bullae is, however, very rare. We report a case in which complete resolution of pulmonary bullae in the left upper lung occurred spontaneously. The management of pulmonary bullae is occasionally made difficult because of gradual progressive enlargement associated with abnormal pulmonary function. Some patients have multiple bulla in both lungs and/or have a history of pulmonary emphysema. Others have a giant bulla without emphysematous change in the lungs. Our present case had treated lung cancer with no evidence of local recurrence. He had no emphysematous change in lung function test and had no complaints, although the high resolution CT scan shows evidence of underlying minimal changes of emphysema. Ortin and Gurney presented three cases of spontaneous reduction in size of bulla. Interestingly, one of them had a marked decrease in the size of a bulla in association with thickening of the wall of the bulla, which was observed in our patient. This case we describe is of interest, not only because of the rarity with which regression of pulmonary bulla has been reported in the literature, but also because of the spontaneous improvements in the radiological picture in the absence of overt infection or tumor. Copyright (2002) Blackwell Science Pty Ltd

Video-assisted thoracoscopy treatment of spontaneous pneumothorax

International Nuclear Information System (INIS)

Chen Haitao; Ren Jian; Che Jiaming; Hang Junbiao; Qiu Weicheng; Chen Zhongyuan

2002-01-01

Objective: To propose a treatment protocol by video thoracoscopy in spontaneous pneumothorax. Methods: One hundred and three patients underwent Video-assisted thoracoscopy (VATS) treatment of spontaneous pneumothorax and hemothorax. Indications included recurrent pneumothorax, persistent air leakage following conservative therapy, complicated hemothorax and CT scan identified bullae formation. Results: No operative deaths occurred, conversion rate was 2.91%, recurrence rate was 0.97%, complication rate was 3.81% and mean postoperative hospital stay was 5.6 days. Conclusions: VATS treatment of spontaneous pneumothorax is better than open chest surgery and also superior than conservative therapy

Spontaneous Dissection of the Superior Mesenteric Artery

International Nuclear Information System (INIS)

Sheldon, Patrick J.; Esther, James B.; Sheldon, Elana L.; Sparks, Steven R.; Brophy, David P.; Oglevie, Steven B.

2001-01-01

Spontaneous dissection of the superior mesenteric artery (SMA) is a rare occurrence, especially when not associated with aortic dissection. Currently, only 28 cases appear to have been reported. Due to the scarcity of cases in the literature, the natural history of isolated, spontaneous SMA dissection is unclear. CT has been reported to be useful for the initial diagnosis of SMA dissection [2-5]. We present two recent cases of spontaneous SMA dissection in which enhanced spiral CT was instrumental in following the disease process and guiding clinical decision making

Endometriosis-related spontaneous diaphragmatic rupture.

Science.gov (United States)

Triponez, Frédéric; Alifano, Marco; Bobbio, Antonio; Regnard, Jean-François

2010-10-01

Non-traumatic, spontaneous diaphragmatic rupture is a rare event whose pathophysiology is not known. We report the case of endometriosis-related spontaneous rupture of the right diaphragm with intrathoracic herniation of the liver, gallbladder and colon. We hypothesize that the invasiveness of endometriotic tissue caused diaphragm fragility, which finally lead to its complete rupture without traumatic event. The treatment consisted of a classical management of diaphragmatic rupture, with excision of the endometriotic nodule followed by medical ovarian suppression for six months.

Spontaneous Scalarization: Dead or Alive?

Science.gov (United States)

Berti, Emanuele; Crispino, Luis; Gerosa, Davide; Gualtieri, Leonardo; Horbatsch, Michael; Macedo, Caio; Okada da Silva, Hector; Pani, Paolo; Sotani, Hajime; Sperhake, Ulrich

2015-04-01

In 1993, Damour and Esposito-Farese showed that a wide class of scalar-tensor theories can pass weak-field gravitational tests and exhibit nonperturbative strong-field deviations away from General Relativity in systems involving neutron stars. These deviations are possible in the presence of ``spontaneous scalarization,'' a phase transition similar in nature to spontaneous magnetization in ferromagnets. More than twenty years after the original proposal, binary pulsar experiments have severely constrained the possibility of spontaneous scalarization occurring in nature. I will show that these experimental constraints have important implications for the torsional oscillation frequencies of neutron stars and for the so-called ``I-Love-Q'' relations in scalar-tensor theories. I will also argue that there is still hope to observe strong scalarization effects, despite the strong experimental bounds on the original mechanism. In particular, I will discuss two mechanisms that could produce strong scalarization in neutron stars: anisotropy and multiscalarization. This work was supported by NSF CAREER Award PHY-1055103.

Detection of target phonemes in spontaneous and read speech.

Science.gov (United States)

Mehta, G; Cutler, A

1988-01-01

Although spontaneous speech occurs more frequently in most listeners' experience than read speech, laboratory studies of human speech recognition typically use carefully controlled materials read from a script. The phonological and prosodic characteristics of spontaneous and read speech differ considerably, however, which suggests that laboratory results may not generalise to the recognition of spontaneous speech. In the present study listeners were presented with both spontaneous and read speech materials, and their response time to detect word-initial target phonemes was measured. Responses were, overall, equally fast in each speech mode. However, analysis of effects previously reported in phoneme detection studies revealed significant differences between speech modes. In read speech but not in spontaneous speech, later targets were detected more rapidly than targets preceded by short words. In contrast, in spontaneous speech but not in read speech, targets were detected more rapidly in accented than in unaccented words and in strong than in weak syllables. An explanation for this pattern is offered in terms of characteristic prosodic differences between spontaneous and read speech. The results support claims from previous work that listeners pay great attention to prosodic information in the process of recognising speech.

Spontaneous CP violation on the lattice

CERN Document Server

Laine, Mikko

2000-01-01

At finite temperatures around the electroweak phase transition, the thermodynamics of the MSSM can be described by a three-dimensional two Higgs doublet effective theory. This effective theory has a phase where CP is spontaneously violated. We study spontaneous CP violation with non-perturbative lattice simulations, and analyse whether one could end up in this phase for any physical MSSM parameter values.

Spontaneous pneumothorax associated with lung cancer

International Nuclear Information System (INIS)

Sung, Dong Wook; Jung, Seung Hyae; Yoon, Yup; Lim, Jae Hoon; Cho, Kyu Soek; Yang, Moon Ho

1991-01-01

Spontaneous pneumothorax is a rare manifestation of lung cancer. Eight cases of pneumothorax found in 1648 patients with lung cancer from 1979-1990 are reported. Histopathologic types of cancer were adenocarcinoma in three cases, squamous cell carcinoma in two cases, bronchioloalveolar carcinoma in two cases, and metastatic renal cell carcinoma in one case. The primary tumor mass was not found even after thoracotomy in two cases. Spontaneous pneumothorax occurred on the ipsilateral side of the cancer. All the patients were more than 40 years old with a history of smoking 1-2 packs a day for 20 to 50 years, and had chronic lung diseases. The authors emphasize that bronchogenic carcinoma may be one of the causes of spontaneous pneumothorax in appropriate clinical settings

Spontaneous generation in medieval Jewish philosophy and theology.

Science.gov (United States)

Gaziel, Ahuva

2012-01-01

The concept of life forms emerging from inanimate matter--spontaneous generation--was widely accepted until the nineteenth century. Several medieval Jewish scholars acknowledged this scientific theory in their philosophical and religious contemplations. Quite interestingly, it served to reinforce diverse, or even opposite, theological conclusions. One approach excluded spontaneously-generated living beings form the biblical account of creation or the story of the Deluge. Underlying this view is an understanding that organisms that generate spontaneously evolve continuously in nature and, therefore, do not require divine intervention in their formation or survival during disastrous events. This naturalistic position reduces the miraculous dimension of reality. Others were of the opinion that spontaneous generation is one of the extraordinary marvels exhibited in this world and, accordingly, this interpretation served to accentuate the divine aspect of nature. References to spontaneous generation also appear in legal writings, influencing practical applications such as dietary laws and actions forbidden on the Sabbath.

Spontaneous low-frequency oscillations in cerebral vessels

DEFF Research Database (Denmark)

Schytz, Henrik W; Hansson, Andreas; Phillip, Dorte

2010-01-01

). Analysis of CA by measurement of spontaneous oscillations in the low-frequency spectrum in cerebral vessels might be a useful tool for assessing risk and investigating different treatment strategies in carotid artery disease (CAD) and stroke. We reviewed studies exploring spontaneous oscillations...

Role of brain-derived neurotrophic factor in the excitatory-inhibitory imbalance during the critical period of postnatal respiratory development in the rat.

Science.gov (United States)

Gao, Xiu-Ping; Zhang, Hanmeng; Wong-Riley, Margaret

2015-11-01

The critical period of respiratory development in rats is a narrow window toward the end of the second postnatal week (P12-13), when abrupt neurochemical, electrophysiological, and ventilatory changes occur, when inhibition dominates over excitation, and when the animals' response to hypoxia is the weakest. The goal of this study was to further test our hypothesis that a major mechanism underlying the synaptic imbalance during the critical period is a reduced expression of brain-derived neurotrophic factor (BDNF) and its TrkB receptors. Our aims were to determine (1) that the inhibitory dominance observed in hypoglossal motoneurons during the critical period was also demonstrable in a key respiratory chemosensor, NTSVL; (2) if in vivo application of a TrkB agonist, 7,8-DHF, would prevent, but a TrkB antagonist, ANA-12, would accentuate the synaptic imbalance; and (3) if hypoxia would also heighten the imbalance. Our results indicate that (1) the synaptic imbalance was evident in the NTSVL during the critical period; (2) intraperitoneal injections of 7,8-DHF prevented the synaptic imbalance during the critical period, whereas ANA-12 in vivo accentuated such an imbalance; and (3) acute hypoxia induced the weakest response in both the amplitude and frequency of sEPSCs during the critical period, but it increased the frequency of sIPSCs during the critical period. Thus, our findings are consistent with and strengthen our hypothesis that BDNF and TrkB play a significant role in inducing a synaptic imbalance during the critical period of respiratory development in the rat. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

Arrays of microLEDs and astrocytes: biological amplifiers to optogenetically modulate neuronal networks reducing light requirement.

Directory of Open Access Journals (Sweden)

Rolando Berlinguer-Palmini

Full Text Available In the modern view of synaptic transmission, astrocytes are no longer confined to the role of merely supportive cells. Although they do not generate action potentials, they nonetheless exhibit electrical activity and can influence surrounding neurons through gliotransmitter release. In this work, we explored whether optogenetic activation of glial cells could act as an amplification mechanism to optical neural stimulation via gliotransmission to the neural network. We studied the modulation of gliotransmission by selective photo-activation of channelrhodopsin-2 (ChR2 and by means of a matrix of individually addressable super-bright microLEDs (μLEDs with an excitation peak at 470 nm. We combined Ca2+ imaging techniques and concurrent patch-clamp electrophysiology to obtain subsequent glia/neural activity. First, we tested the μLEDs efficacy in stimulating ChR2-transfected astrocyte. ChR2-induced astrocytic current did not desensitize overtime, and was linearly increased and prolonged by increasing μLED irradiance in terms of intensity and surface illumination. Subsequently, ChR2 astrocytic stimulation by broad-field LED illumination with the same spectral profile, increased both glial cells and neuronal calcium transient frequency and sEPSCs suggesting that few ChR2-transfected astrocytes were able to excite surrounding not-ChR2-transfected astrocytes and neurons. Finally, by using the μLEDs array to selectively light stimulate ChR2 positive astrocytes we were able to increase the synaptic activity of single neurons surrounding it. In conclusion, ChR2-transfected astrocytes and μLEDs system were shown to be an amplifier of synaptic activity in mixed corticalneuronal and glial cells culture.

Arrays of microLEDs and astrocytes: biological amplifiers to optogenetically modulate neuronal networks reducing light requirement.

Science.gov (United States)

Berlinguer-Palmini, Rolando; Narducci, Roberto; Merhan, Kamyar; Dilaghi, Arianna; Moroni, Flavio; Masi, Alessio; Scartabelli, Tania; Landucci, Elisa; Sili, Maria; Schettini, Antonio; McGovern, Brian; Maskaant, Pleun; Degenaar, Patrick; Mannaioni, Guido

2014-01-01

In the modern view of synaptic transmission, astrocytes are no longer confined to the role of merely supportive cells. Although they do not generate action potentials, they nonetheless exhibit electrical activity and can influence surrounding neurons through gliotransmitter release. In this work, we explored whether optogenetic activation of glial cells could act as an amplification mechanism to optical neural stimulation via gliotransmission to the neural network. We studied the modulation of gliotransmission by selective photo-activation of channelrhodopsin-2 (ChR2) and by means of a matrix of individually addressable super-bright microLEDs (μLEDs) with an excitation peak at 470 nm. We combined Ca2+ imaging techniques and concurrent patch-clamp electrophysiology to obtain subsequent glia/neural activity. First, we tested the μLEDs efficacy in stimulating ChR2-transfected astrocyte. ChR2-induced astrocytic current did not desensitize overtime, and was linearly increased and prolonged by increasing μLED irradiance in terms of intensity and surface illumination. Subsequently, ChR2 astrocytic stimulation by broad-field LED illumination with the same spectral profile, increased both glial cells and neuronal calcium transient frequency and sEPSCs suggesting that few ChR2-transfected astrocytes were able to excite surrounding not-ChR2-transfected astrocytes and neurons. Finally, by using the μLEDs array to selectively light stimulate ChR2 positive astrocytes we were able to increase the synaptic activity of single neurons surrounding it. In conclusion, ChR2-transfected astrocytes and μLEDs system were shown to be an amplifier of synaptic activity in mixed corticalneuronal and glial cells culture.

Spontaneous rupture of vaginal enterocele

DEFF Research Database (Denmark)

Svendsen, J H; Galatius, H; Hansen, P K

1985-01-01

Spontaneous rupture of an enterocele is a rare complication. Only 24 cases including the present case have been reported in the literature. The patients were elderly and had had at least one vaginal operation. The patients were remarkably unaffected symptomatically on admission.......Spontaneous rupture of an enterocele is a rare complication. Only 24 cases including the present case have been reported in the literature. The patients were elderly and had had at least one vaginal operation. The patients were remarkably unaffected symptomatically on admission....

Spontaneous emission spectra and simulating multiple spontaneous generation coherence in a five-level atomic medium

International Nuclear Information System (INIS)

Li Jiahua; Liu Jibing; Qi Chunchao; Chen Aixi

2006-01-01

We investigate the features of the spontaneous emission spectra in a coherently driven cold five-level atomic system by means of a radio frequency (rf) or microwave field driving a hyperfine transition within the ground state. It is shown that a few interesting phenomena such as spectral-line narrowing, spectral-line enhancement, spectral-line suppression, and spontaneous emission quenching can be realized by modulating the frequency and intensity of the rf-driving field in our system. In the dressed-state picture of the coupling and rf-driving fields, we find that this coherently driven atomic system has three close-lying levels so that multiple spontaneously generated coherence (SGC) arises. Our considered atomic model can be found in real atoms, such as rubidium or sodium, so a corresponding experiment can be done to observe the expected phenomena related to SGC reported by Fountoulakis et al. [Phys. Rev. A 73, 033811 (2006)], since no rigorous conditions are required

A new class of spontaneously polarized materials

DEFF Research Database (Denmark)

Field, David; Plekan, Oksana; Cassidy, Andrew

2011-01-01

Very large electric fields form spontaneously within films of seemingly prosaic chemicals such as nitrous oxide or propane.We describe how the discovery of this unexpected phenomenon took place and how we attempt to understand the nature of the new class of spontaneously polarized materials...

Spontaneous rupture of choledochal cyst: case report

International Nuclear Information System (INIS)

Shin, Ho Seob; Nam, Kyung Jin; Lee, Jin Hwa; Kim, Chan Sung; Choi, Jong Cheol; Oh, Jong Young

2002-01-01

Spontaneous rupture of a choledochal cyst leading to biliary peritonitis is a rare complication which can be fatal if not promptly diagnosed. The authors report the ultrasound and CT findings of two cases of spontaneous choledochal cystic rupture and the biliary peritonitis which ensued

Spontaneous rupture of choledochal cyst: case report

Energy Technology Data Exchange (ETDEWEB)

Shin, Ho Seob; Nam, Kyung Jin; Lee, Jin Hwa; Kim, Chan Sung; Choi, Jong Cheol; Oh, Jong Young [Dong-a University College of Medicine, Pusan (Korea, Republic of)

2002-11-01

Spontaneous rupture of a choledochal cyst leading to biliary peritonitis is a rare complication which can be fatal if not promptly diagnosed. The authors report the ultrasound and CT findings of two cases of spontaneous choledochal cystic rupture and the biliary peritonitis which ensued.

Spontaneous symmetry breaking and its cosmological consequences

International Nuclear Information System (INIS)

Kobzarev, I.Yu.

1975-01-01

The concept of symmetry and of the spontaneous symmetry breaking are presented in popular form as applied to quantum physics. Though the presence of the spontaneous symmetry breaking is not proved directly for interactions of elementary particles, on considering the hypothesis of its presence as applied to the hot Universe theory a possibility of obtaining rather uncommon cosmological consequences is discussed. In particular, spontaneous symmetry breaking of vacuum and the rather hot Universe lead necessarily to the presence of the domain structure of the Universe with the surfase energy at the domain interface in the form of a real physical object

Shared risk aversion in spontaneous and induced abortion.

Science.gov (United States)

Catalano, Ralph; Bruckner, Tim A; Karasek, Deborah; Adler, Nancy E; Mortensen, Laust H

2016-05-01

Does the incidence of spontaneous abortion correlate positively over conception cohorts with the incidence of non-clinically indicated induced abortion as predicted by shared risk aversion? We find that the number of spontaneous and non-clinically indicated induced abortions correlates in conception cohorts, suggesting that risk aversion affects both the conscious and non-conscious mechanisms that control parturition. Much literature speculates that natural selection conserved risk aversion because the trait enhanced Darwinian fitness. Risk aversion, moreover, supposedly influences all decisions including those that individuals can and cannot report making. We argue that these circumstances, if real, would manifest in conscious and non-conscious decisions to invest in prospective offspring, and therefore affect incidence of induced and spontaneous abortion over time. Using data from Denmark, we test the hypothesis that monthly conception cohorts yielding unexpectedly many non-clinically indicated induced abortions also yield unexpectedly many spontaneous abortions. The 180 month test period (January 1995 through December 2009), yielded 1 351 800 gestations including 156 780 spontaneous as well as 233 280 induced abortions 9100 of which were clinically indicated. We use Box-Jenkins transfer functions to adjust the incidence of spontaneous and non-clinically indicated induced abortions for autocorrelation (including seasonality), cohort size, and fetal as well as gestational anomalies over the 180-month test period. We use cross-correlation to test our hypothesized association. We find a positive association between spontaneous and non-clinically indicated induced abortions. This suggests, consistent with our theory, that mothers of conception cohorts that yielded more spontaneous abortions than expected opted more frequently than expected for non-clinically indicated induced abortion. Limitations of our work include that even the world's best registration system

Group theory of spontaneous symmetry breaking

International Nuclear Information System (INIS)

Ghaboussi, F.

1987-01-01

The connection between the minimality of the Higgs field potential and the maximal little groups of its representation obtained by spontaneous symmetry breaking is analyzed. It is shown that for several representations the lowest minimum of the potential is related to the maximal little group of those representations. Furthermore, a practical necessity criterion is given for the representation of the Higgs field needed for spontaneous symmetry breaking

Spontaneous polyploidization in cucumber.

Science.gov (United States)

Ramírez-Madera, Axel O; Miller, Nathan D; Spalding, Edgar P; Weng, Yiqun; Havey, Michael J

2017-07-01

This is the first quantitative estimation of spontaneous polyploidy in cucumber and we detected 2.2% polyploids in a greenhouse study. We provide evidence that polyploidization is consistent with endoreduplication and is an on-going process during plant growth. Cucumber occasionally produces polyploid plants, which are problematic for growers because these plants produce misshaped fruits with non-viable seeds. In this study, we undertook the first quantitative study to estimate the relative frequency of spontaneous polyploids in cucumber. Seeds of recombinant inbred lines were produced in different environments, plants were grown in the field and greenhouse, and flow cytometry was used to establish ploidies. From 1422 greenhouse-grown plants, the overall relative frequency of spontaneous polyploidy was 2.2%. Plants possessed nuclei of different ploidies in the same leaves (mosaic) and on different parts of the same plant (chimeric). Our results provide evidence of endoreduplication and polysomaty in cucumber, and that it is an on-going and dynamic process. There was a significant effect (p = 0.018) of seed production environment on the occurrence of polyploid plants. Seed and seedling traits were not accurate predictors of eventual polyploids, and we recommend that cucumber producers rogue plants based on stature and leaf serration to remove potential polyploids.

Spontaneous Achilles tendon rupture in alkaptonuria | Mohammed ...

African Journals Online (AJOL)

Spontaneous Achilles tendon ruptures are uncommon. We present a 46-year-old man with spontaneous Achilles tendon rupture due to ochronosis. To our knowledge, this has not been previously reported in Sudan literature. The tendon of the reported patient healed well after debridement and primary repairs.

Spontaneous magnetization in high-density quark matter

DEFF Research Database (Denmark)

Tsue, Yasuhiko; da Providência, João; Providência, Constanca

2015-01-01

It is shown that spontaneous magnetization occurs due to the anomalous magnetic moments of quarks in high-density quark matter under the tensor-type four-point interaction. The spin polarized condensate for each flavor of quark appears at high baryon density, which leads to the spontaneous magnet...

Children's Spontaneous Vocalisations during Play: Aesthetic Dimensions

Science.gov (United States)

Countryman, June; Gabriel, Martha; Thompson, Katherine

2016-01-01

This paper explores the phenomenon of spontaneous vocalisations in the self-chosen, unstructured outdoor play of children aged 3-12. Spontaneous vocalisations encompass the whole range of children's unprompted, natural, expressive vocal soundings beyond spoken language. Non-participant observations at childcare centres and on elementary school…

Spontaneous baryogenesis from asymmetric inflaton

International Nuclear Information System (INIS)

Takahashi, Fuminobu

2015-10-01

We propose a variant scenario of spontaneous baryogenesis from asymmetric inflaton based on current-current interactions between the inflaton and matter fields with a non-zero B-L charge. When the inflaton starts to oscillate around the minimum after inflation, it may lead to excitation of a CP-odd component, which induces an effective chemical potential for the B-L number through the current-current interactions. We study concrete inflation models and show that the spontaneous baryogenesis scenario can be naturally implemented in the chaotic inflation in supergravity.

Radiologic findings of acute spontaneous subdural hematomas

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyun Jung; Bae, Won Kyong; Gyu, Cha Jang; Kim, Gun Woo; Cho, Won Su; Kim, Il Young; Lee, Kyung Suk [Soonchunhyang University, Chonan (Korea, Republic of). Chonan Hospital

1998-03-01

To evaluate the characteristic CT and cerebral angiographic findings in patients with acute spontaneous subdural hematomas and correlate these imaging findings with causes of bleeding and clinical outcome. Twenty-one patients with nontraumatic acute spontaneous subdural hematoma presenting during the last five years underwent CT scanning and cerebral angiography was performed in twelve. To determine the cause of bleedings, CT and angiographic findings were retrospectively analysed. Clinical history, laboratory and operative findings, and final clinical outcome were reviewed. Acute spontaneous subdural hematoma is a rare condition, and the mortality rate is high. In patients with acute spontaneous subdural hematoma, as seen on CT, associated subarachnoid or intracerebral hemorrhage is strongly indicative of intracerebral vascular abnormalities such as aneurysm and arteriovenous malformation, and cerebral angiography is necessary. To ensure proper treatment and thus markedly reduce mortality, the causes of bleedings should be prompty determined by means of cerebral angiography. (author). 20 refs., 1 tab., 4 figs.

Spontaneous onset of Complex Regional Pain Syndrome

NARCIS (Netherlands)

de Rooij, A.M.; Perez, R.S.G.M.; Huygen, F.J.; van Eijs, F.; van Kleef, M.; Bauer, M.C.R.; van Hilten, J.J.; Marinus, J.

2010-01-01

Complex Regional Pain Syndrome (CRPS) usually develops after a noxious event, but spontaneous onsets have been described in 3-11% of the cases. The existence of spontaneous-onset CRPS is highly debated and the aim of the present study was therefore to compare the phenotypic characteristics of CRPS

Spatial diversity of spontaneous activity in the cortex

Directory of Open Access Journals (Sweden)

Andrew Yong-Yi Tan

2015-09-01

Full Text Available The neocortex is a layered sheet across which a basic organization is thought to widely apply. The variety of spontaneous activity patterns is similar throughout the cortex, consistent with the notion of a basic cortical organization. However, the basic organization is only an outline which needs adjustments and additions to account for the structural and functional diversity across cortical layers and areas. Such diversity suggests that spontaneous activity is spatially diverse in any particular behavioral state. Accordingly, this review summarizes the laminar and areal diversity in cortical activity during fixation and slow oscillations, and the effects of attention, anesthesia and plasticity on the cortical distribution of spontaneous activity. Among questions that remain open, characterizing the spatial diversity in spontaneous membrane potential may help elucidate how differences in circuitry among cortical regions supports their varied functions. More work is also needed to understand whether cortical spontaneous activity not only reflects cortical circuitry, but also contributes to determining the outcome of plasticity, so that it is itself a factor shaping the functional diversity of the cortex.

Socioeconomic position and the risk of spontaneous abortion

DEFF Research Database (Denmark)

Norsker, Filippa Nyboe; Espenhain, Laura; rogvi, Sofie

2012-01-01

To investigate the relationship between different indicators of socioeconomic position and the risk of spontaneous abortion.......To investigate the relationship between different indicators of socioeconomic position and the risk of spontaneous abortion....

Spontaneous indices are inconsistent with arterial baroreflex gain.

Science.gov (United States)

Lipman, Ruth D; Salisbury, Julie K; Taylor, J Andrew

2003-10-01

Spontaneously occurring, parallel fluctuations in arterial pressure and heart period are frequently used as indices of baroreflex function. Despite the convenience of spontaneous indices, their relation to the arterial baroreflex remains unclear. Therefore, in 97 volunteers, we derived 5 proposed indices (sequence method, alpha-index, transfer function, low-frequency transfer function, and impulse response function), compared them with arterial baroreflex gain (by the modified Oxford pharmacologic technique), and examined their relation to carotid distensibility and respiratory sinus arrhythmia. The subjects comprised men and women (n=41) aged 25 to 86 years, 30% of whom had established coronary artery disease. Generally, the indices were correlated with each other (except alpha-index and low-frequency transfer function) and with baroreflex gain. However, the Bland-Altman method demonstrated that the spontaneous indices had limits of agreement as large as the baroreflex gain itself. Even in individuals within the lowest tertile of baroreflex gain for whom baroreflex gain appears to be the most clinically relevant, spontaneous indices failed to relate to baroreflex gain. In fact, for these individuals, there was no correlation between any index and baroreflex gain. Forward stepwise linear regression showed that all spontaneous indices and baroreflex gain were related to respiratory sinus arrhythmia, but only baroreflex gain was related to carotid distensibility. Therefore, these data suggest that spontaneous indices are inadequate estimates of gain and are inconsistent with arterial baroreflex function.

Distinct spontaneous shrinkage of a sporadic vestibular schwannoma

DEFF Research Database (Denmark)

Huang, Xiaowen; Cayé-Thomasen, Per; Stangerup, Sven-Eric

2013-01-01

on "shrinkage" or "negative growth" or "regression" or "involution" of the tumor were selected, and the contents on the rate, extent and mechanism of spontaneous tumor shrinkage were extracted and reviewed. The reported rate of spontaneous shrinkage of vestibular schwannoma is 5-10% of patients managed......We present a case with outspoken spontaneous vestibular schwannoma shrinkage and review the related literature. The patient was initially diagnosed with a left-sided, intrameatal vestibular schwannoma, which subsequently grew into the cerebello-pontine angle (CPA), followed by total shrinkage...... of the CPA component without any intervention over a 12-year observation period. The literature on spontaneous tumor shrinkage was retrieved by searching the subject terms "vestibular schwannoma, conservative management" in PubMed/MEDLINE database, without a time limit. Of the published data, the articles...

Spontaneous breathing during lung-protective ventilation in an experimental acute lung injury model: high transpulmonary pressure associated with strong spontaneous breathing effort may worsen lung injury.

Science.gov (United States)

Yoshida, Takeshi; Uchiyama, Akinori; Matsuura, Nariaki; Mashimo, Takashi; Fujino, Yuji

2012-05-01

We investigated whether potentially injurious transpulmonary pressure could be generated by strong spontaneous breathing and exacerbate lung injury even when plateau pressure is limited to ventilation, each combined with weak or strong spontaneous breathing effort. Inspiratory pressure for low tidal volume ventilation was set at 10 cm H2O and tidal volume at 6 mL/kg. For moderate tidal volume ventilation, the values were 20 cm H2O and 7-9 mL/kg. The groups were: low tidal volume ventilation+spontaneous breathingweak, low tidal volume ventilation+spontaneous breathingstrong, moderate tidal volume ventilation+spontaneous breathingweak, and moderate tidal volume ventilation+spontaneous breathingstrong. Each group had the same settings for positive end-expiratory pressure of 8 cm H2O. Respiratory variables were measured every 60 mins. Distribution of lung aeration and alveolar collapse were histologically evaluated. Low tidal volume ventilation+spontaneous breathingstrong showed the most favorable oxygenation and compliance of respiratory system, and the best lung aeration. By contrast, in moderate tidal volume ventilation+spontaneous breathingstrong, the greatest atelectasis with numerous neutrophils was observed. While we applied settings to maintain plateau pressure at ventilation+spontaneous breathingstrong, transpulmonary pressure rose >33 cm H2O. Both minute ventilation and respiratory rate were higher in the strong spontaneous breathing groups. Even when plateau pressure is limited to mechanical ventilation, transpulmonary pressure and tidal volume should be strictly controlled to prevent further lung injury.

Cigarette, alcohol, and caffeine consumption: risk factors for spontaneous abortion

DEFF Research Database (Denmark)

Rasch, Vibeke

2003-01-01

OBJECTIVE: To study the association between cigarette, alcohol, and caffeine consumption and the occurrence of spontaneous abortion. METHODS: The study population consisted of 330 women with spontaneous abortion and 1168 pregnant women receiving antenatal care. A case-control design was utilized;...... units alcohol per week and 375 mg or more caffeine per day during pregnancy may increase the risk of spontaneous abortion.......OBJECTIVE: To study the association between cigarette, alcohol, and caffeine consumption and the occurrence of spontaneous abortion. METHODS: The study population consisted of 330 women with spontaneous abortion and 1168 pregnant women receiving antenatal care. A case-control design was utilized......; cases were defined as women with a spontaneous abortion in gestational week 6-16 and controls as women with a live fetus in gestational week 6-16. The variables studied comprise age, parity, occupational situation, cigarette, alcohol, and caffeine consumption. The association between cigarette, alcohol...

Spontaneous Hedonic Reactions to Social Media Cues.

Science.gov (United States)

van Koningsbruggen, Guido M; Hartmann, Tilo; Eden, Allison; Veling, Harm

2017-05-01

Why is it so difficult to resist the desire to use social media? One possibility is that frequent social media users possess strong and spontaneous hedonic reactions to social media cues, which, in turn, makes it difficult to resist social media temptations. In two studies (total N = 200), we investigated less-frequent and frequent social media users' spontaneous hedonic reactions to social media cues using the Affect Misattribution Procedure-an implicit measure of affective reactions. Results demonstrated that frequent social media users showed more favorable affective reactions in response to social media (vs. control) cues, whereas less-frequent social media users' affective reactions did not differ between social media and control cues (Studies 1 and 2). Moreover, the spontaneous hedonic reactions to social media (vs. control) cues were related to self-reported cravings to use social media and partially accounted for the link between social media use and social media cravings (Study 2). These findings suggest that frequent social media users' spontaneous hedonic reactions in response to social media cues might contribute to their difficulties in resisting desires to use social media.

Spontaneous globe luxation associated with chronic obstructive pulmonary disease

Directory of Open Access Journals (Sweden)

M Ashok Kumar

2012-01-01

Full Text Available Spontaneous globe luxation is a rarely reported condition which can lead to complications like optic neuropathy. Common causes are thyroid eye disease, shallow orbit and floppy eyelid syndrome. We report a case of spontaneous globe luxation with the onset and severity associated with chronic obstructive pulmonary disease (COPD. To our knowledge, this is the first case of spontaneous globe luxation associated with COPD.

Surgical management of spontaneous hypertensive brainstem hemorrhage

Directory of Open Access Journals (Sweden)

Bal Krishna Shrestha

2015-09-01

Full Text Available Spontaneous hypertensive brainstem hemorrhage is the spontaneous brainstem hemorrhage associated with long term hypertension but not having definite focal or objective lesion. It is a catastrophic event which has a poor prognosis and usually managed conservatively. It is not uncommon, especially in eastern Asian populations, accounting approximately for 10% of the intracerebral hemorrhage. Before the advent of computed tomography, the diagnosis of brainstem hemorrhage was usually based on the clinical picture or by autopsy and believed to be untreatable via surgery. The introduction of computed tomography permitted to categorize the subtypes of brainstem hemorrhage with more predicted outcome. Continuous ongoing developments in the stereotactic surgery and microsurgery have added more specific surgical management in these patients. However, whether to manage conservatively or promptly with surgical evacuation of hematoma is still a controversy. Studies have shown that an accurate prognostic assessment based on clinical and radiological features on admission is critical for establishing a reasonable therapeutic approach. Some authors have advocate conservative management, whereas others have suggested the efficacy of surgical treatment in brainstem hemorrhage. With the widening knowledge in microsurgical techniques as well as neuroimaging technology, there seems to have more optimistic hope of surgical management of spontaneous hypertensive brainstem hemorrhage for better prognosis. Here we present five cases of severe spontaneous hypertensive brainstem hemorrhage patients who had undergone surgery; and explore the possibilities of surgical management in patients with the spontaneous hypertensive brainstem hemorrhage.

Active hippocampal networks undergo spontaneous synaptic modification.

Directory of Open Access Journals (Sweden)

Masako Tsukamoto-Yasui

Full Text Available The brain is self-writable; as the brain voluntarily adapts itself to a changing environment, the neural circuitry rearranges its functional connectivity by referring to its own activity. How the internal activity modifies synaptic weights is largely unknown, however. Here we report that spontaneous activity causes complex reorganization of synaptic connectivity without any external (or artificial stimuli. Under physiologically relevant ionic conditions, CA3 pyramidal cells in hippocampal slices displayed spontaneous spikes with bistable slow oscillations of membrane potential, alternating between the so-called UP and DOWN states. The generation of slow oscillations did not require fast synaptic transmission, but their patterns were coordinated by local circuit activity. In the course of generating spontaneous activity, individual neurons acquired bidirectional long-lasting synaptic modification. The spontaneous synaptic plasticity depended on a rise in intracellular calcium concentrations of postsynaptic cells, but not on NMDA receptor activity. The direction and amount of the plasticity varied depending on slow oscillation patterns and synapse locations, and thus, they were diverse in a network. Once this global synaptic refinement occurred, the same neurons now displayed different patterns of spontaneous activity, which in turn exhibited different levels of synaptic plasticity. Thus, active networks continuously update their internal states through ongoing synaptic plasticity. With computational simulations, we suggest that with this slow oscillation-induced plasticity, a recurrent network converges on a more specific state, compared to that with spike timing-dependent plasticity alone.

Shared risk aversion in spontaneous and induced abortion

DEFF Research Database (Denmark)

Catalano, Ralph; Bruckner, Tim A.; Karasek, Deborah

2016-01-01

spontaneous and non-clinically indicated induced abortions. This suggests, consistent with our theory, that mothers of conception cohorts that yielded more spontaneous abortions than expected opted more frequently than expected for non-clinically indicated induced abortion. LIMITATIONS, REASONS FOR CAUTION...

Spontaneous passage of long, sharp gastrointestinal foreign body in a child.

Science.gov (United States)

Karthikeyan, Vilvapathy Senguttuvan; Ansari, Mohammed Gaffoor; Suresh, Ramasamy; Easwaran, Bettaiyagowder

2015-01-19

Foreign body (FB) ingestion is a common problem in children. Up to 90% of these FBs pass spontaneously. FBs reaching the stomach usually pass out spontaneously. Exceptions to this spontaneous passage include a long FB that cannot cross the pylorus, duodenum or ileocaecal junction. We present a case of a 9-year boy who accidentally ingested a long paper pin, which spontaneously passed in 26 h. This case is being reported to highlight the successful spontaneous passage of a 4 cm long sharp foreign body in a child. 2015 BMJ Publishing Group Ltd.

Detection of target phonemes in spontaneous and read speech

OpenAIRE

Mehta, G.; Cutler, A.

1988-01-01

Although spontaneous speech occurs more frequently in most listeners’ experience than read speech, laboratory studies of human speech recognition typically use carefully controlled materials read from a script. The phonological and prosodic characteristics of spontaneous and read speech differ considerably, however, which suggests that laboratory results may not generalize to the recognition of spontaneous and read speech materials, and their response time to detect word-initial target phonem...

Spontaneous Splenic Rupture in Melanoma

Directory of Open Access Journals (Sweden)

Hadi Mirfazaelian

2014-01-01

Full Text Available Spontaneous rupture of spleen due to malignant melanoma is a rare situation, with only a few case reports in the literature. This study reports a previously healthy, 30-year-old man who came with chief complaint of acute abdominal pain to emergency room. On physical examination, abdominal tenderness and guarding were detected to be coincident with hypotension. Ultrasonography revealed mild splenomegaly with moderate free fluid in abdominopelvic cavity. Considering acute abdominal pain and hemodynamic instability, he underwent splenectomy with splenic rupture as the source of bleeding. Histologic examination showed diffuse infiltration by tumor. Immunohistochemical study (positive for S100, HMB45, and vimentin and negative for CK, CD10, CK20, CK7, CD30, LCA, EMA, and chromogranin confirmed metastatic malignant melanoma. On further questioning, there was a past history of a nasal dark skin lesion which was removed two years ago with no pathologic examination. Spontaneous (nontraumatic rupture of spleen is an uncommon situation and it happens very rarely due to neoplastic metastasis. Metastasis of malignant melanoma is one of the rare causes of the spontaneous rupture of spleen.

Q-feber som årsag til spontan abort

DEFF Research Database (Denmark)

Nielsen, Stine Yde; Mølbak, Kåre; Hjøllund, Niels Henrik

2011-01-01

Q-fever is a zoonotic infection. Pregnant women constitute a specific risk group as the infection may cause spontaneous abortion, intrauterine death, growth retardation, oligohydramnios and premature birth. A 39 year-old veterinarian had a spontaneous abortion in pregnancy week seven. During the ...

Spontaneously broken global symmetries and cosmology

International Nuclear Information System (INIS)

Shafi, Q.; Vilenkin, A.

1984-01-01

Phase transitions associated with spontaneously broken global symmetries, in case these occur in nature, can have important cosmological implications. This is illustrated through two examples. The first one shows how the spontaneous breaking of a global U(1) symmetry, present, for instance, in the minimal SU(5) model, can lead to an inflationary phase. The second example illustrates how topologically stable strings associated with the breaking of U(1) symmetry make an appearance at (or near) the end of the inflationary era

Flow Friction or Spontaneous Ignition?

Science.gov (United States)

Stoltzfus, Joel M.; Gallus, Timothy D.; Sparks, Kyle

2012-01-01

"Flow friction," a proposed ignition mechanism in oxygen systems, has proved elusive in attempts at experimental verification. In this paper, the literature regarding flow friction is reviewed and the experimental verification attempts are briefly discussed. Another ignition mechanism, a form of spontaneous combustion, is proposed as an explanation for at least some of the fire events that have been attributed to flow friction in the literature. In addition, the results of a failure analysis performed at NASA Johnson Space Center White Sands Test Facility are presented, and the observations indicate that spontaneous combustion was the most likely cause of the fire in this 2000 psig (14 MPa) oxygen-enriched system.

Spontaneously broken abelian gauge invariant supersymmetric model

International Nuclear Information System (INIS)

Mainland, G.B.; Tanaka, K.

A model is presented that is invariant under an Abelian gauge transformation and a modified supersymmetry transformation. This model is broken spontaneously, and the interplay between symmetry breaking, Goldstone particles, and mass breaking is studied. In the present model, spontaneously breaking the Abelian symmetry of the vacuum restores the invariance of the vacuum under a modified supersymmetry transformation. (U.S.)

Spontaneous Perforation of Pyometra: A Case Report

Directory of Open Access Journals (Sweden)

2006-01-01

Full Text Available Pyometra is the accumulation of purulent material in the uterine cavity. Its reported incidence is 0.01–0.5% in gynecologic patients; however, as far as elderly patients are concerned, its incidence is 13.6% [3]. The most common cause of pyometra is malignant diseases of genital tract and the consequences of their treatment (radiotherapy. Other causes are benign tumors like leiomyoma, endometrial polyps, senile cervicitis, cervical occlusion after surgery, puerperal infections, and congenital cervical anomalies. Spontaneous rupture of the uterus is an extremely rare complication of pyometra. To our knowledge, only 21 cases of spontaneous perforation of pyometra have been reported in English literature since 1980. This paper reports an additional case of spontaneous uterine rupture.

Spontaneous regression of metastases from malignant melanoma: a case report

DEFF Research Database (Denmark)

Kalialis, Louise V; Drzewiecki, Krzysztof T; Mohammadi, Mahin

2008-01-01

A case of a 61-year-old male with widespread metastatic melanoma is presented 5 years after complete spontaneous cure. Spontaneous regression occurred in cutaneous, pulmonary, hepatic and cerebral metastases. A review of the literature reveals seven cases of regression of cerebral metastases......; this report is the first to document complete spontaneous regression of cerebral metastases from malignant melanoma by means of computed tomography scans. Spontaneous regression is defined as the partial or complete disappearance of a malignant tumour in the absence of all treatment or in the presence...

Novel folliculin (FLCN) mutation and familial spontaneous pneumothorax.

Science.gov (United States)

Zhu, J-F; Shen, X-Q; Zhu, F; Tian, L

2017-01-01

Familial spontaneous pneumothorax is one of the characteristics of Birt-Hogg-Dubé syndrome (BHDS), which is an autosomal dominant disease caused by the mutation of folliculin (FLCN). To investigate the mutation of FLCN gene in a familial spontaneous pneumothorax. Prospective case study. Clinical and genetic data of a Chinese family with four patients who presented spontaneous pneumothorax in the absence of skin lesions or renal tumors were collected. CT scan of patient's lung was applied for observation of pneumothorax. DNA sequencing of the coding exons (4-14 exons) of FLCN was performed for all 11 members of the family and 100 unrelated healthy controls. CT scan of patient's lung showed spontaneous pneumothorax. A mutation (c. 510C > G) that leads to a premature stop codon (p. Y170X) was found in the proband using DNA sequencing of coding exons (4-14 exons) of FLCN. This mutation was also observed in the other affected members of the family. A nonsense mutation of FLCN was found in a spontaneous pneumothorax family. Our results expand the mutational spectrum of FLCN in patients with BHDS. © The Author 2016. Published by Oxford University Press on behalf of the Association of Physicians. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

EU-FP7-iMARS: analysis of Mars multi-resolution images using auto-coregistration, data mining and crowd source techniques: A Status Report

Science.gov (United States)

Muller, Jan-Peter; Sidiropoulos, Panagiotis; Tao, Yu; Gwinner, Klaus; Willner, Konrad; Fanara, Lida; Waehlisch, Marita; Walter, Sebastian; Schreiner, Bjoern; Steikert, Ralf; Ivanov, Anton B.; Cantini, Federico; Wardlaw, Jessica; Sprinks, James Christopher; Giordano, Michele; Kim, Jungrack; Houghton, Robert; Bamford, Steven

2016-10-01

There has been a revolution in 3D surface imaging of Mars over the last 12 years with systematic stereoscopy from HRSC and the production for almost 50% of the Martian surface of DTMs and ORIs. The iMars project has been exploiting this unique set of 3D products as a basemap to co-register NASA imagery going back to the 1970s. DLR have produced 3D HRSC mosaic products for large regions with c. 100 individual strips/region (MC-11E/W). UCL have developed an automated processing chain for CTX and HiRISE 3D processing to densify this global HRSC dataset with DTMs down to 18m and 75cm respectively [1]. A fully Automated Co-Registration and Orthorectification (ACRO) system has been developed at UCL and applied to the production of around 8,000 images co-registered to a HRSC pixel (typically 12.5m) and orthorectified to HRSC DTMs of 50-150m spacing [2]. These images are viewable through an OGC-compliant webGIS developed at FUB including tools for viewing sequences over the same area [3]. Corresponding MARSIS and SHARAD data can be viewed through the QGIS plugin available [4]. An automated data mining system is being developed at UCL [5] for change detection to search and classify features in images going back to Viking Orbiter of IFoV ≤100m. In parallel, a citizen science project at Nottingham University [6] is defining training samples for classification of change features and eventually for verification of change [7]. Scientific applications include change mapping over the SPRC [8], mass movements near the North Pole [9]; dark streaks [10] CRISM mapping of mineralogy of dust in the SPRC "Swiss cheese" layers [11] and mapping of dune movement [12]. [1] Tao, Y. & J.-P. Muller LPSC16-2074; [2] Gwinner, K. et al. EPSC15-672; [3] van Gasselt, S. et al. EPSC14-693; [4] Ivanov, A. & Cantini, F. EPSC16; [5] Sidiropoulos, P. & J.-P. Muller EPSC16; [6] Sprinks et al. EPSC16; [7] Wardlaw et al. EPSC16; [8] Putri et al., EPSC16;[9] Fanara, L. et al. EPSC 16; [10] Schreiner, B. et

Imaging of early spontaneous osteonecrosis and osteoarthritis of the knee

International Nuclear Information System (INIS)

Kusayama, Takeshi; Tomatsu, Taisuke

1999-01-01

In this paper, the available of MRI in diagnosis on early spontaneous osteonecrosis and osteoarthritis was investigated. Subjects were 5 cases (5 knees) with spontaneous osteonecrosis (stage 1 in Koshino's classification) and 96 cases (104 knees) in osteoarthritis who were more than 50 years old. Patients with an early spontaneous osteonecrosis were elderly females and had night pain and severe spontaneous pain. On MRI, lesions of all cases were clearly detected in early stage. On the other hand, only 47 of 104 knees (45%) were detected in patients with osteoarthritis, and mirror lesions at shank sides were detected in 45 of 47 knees. These results suggest that it is possible to diagnose early spontaneous osteonecrosis from osteoarthritis by MRI image with the clue to mirror lesion at shank sides, incidence, stage, etc. On the diagnosis of early spontaneous osteonecrosis, MRI image should be performed as soon as possible if a patient was older, had no anamnesis of lesions, and no changes by the X-ray radiography in spite of severe pain of the knee joints. (K.H.)

Spontaneous infected biloma: case report | Kimani | East African ...

African Journals Online (AJOL)

Biloma is defined as any collection of bile outside the biliary tree. It mainly results from surgical complications and abdominal trauma. Spontaneous biloma is extremely rare and is occasionally associated with choledocholithiasis. This report describes a case of spontaneous biloma diagnosed radiologically and confirmed at ...

Spontaneous resolution of post-traumatic chronic subdural hematoma

African Journals Online (AJOL)

Here, we present a case of spontaneously resolved post-traumatic bilateral chronic subdural hematoma within a period of one month in a 55-year-old male and we discuss the probable mechanisms of pathophysiology in the spontaneous resolution of chronic subdural hematoma. Keywords: Antiaggregation therapy, chronic ...

Spontaneous symmetry breaking in N=3 supergravity

International Nuclear Information System (INIS)

Zinov'ev, Yu.M.

1986-01-01

The possibility of the spontaneous symmetry breaking without a cosmological term in N=3 supergravity is investigated. A new, dual version of N=3 supergravity - U(3)-supergravity is constructed. Such a theory is shown to admit a spontaneous supersymmetry breaking without a cosmological term and with three arbitrary scales, including partial super-Higgs effect N=3 → N=2 and N=3 → N=1

Symmetry restoration in spontaneously broken induced gravity

International Nuclear Information System (INIS)

Amati, D.; Russo, J.

1990-01-01

We investigate the recuperation of expected invariant behaviours in a non-metric gravity theory in which the full general relativistic invariance is broken spontaneously. We show how dangerous increasing energy behaviours of physical amplitudes cancel in a highly non-trivial way. This evidences the expected loss of the vacuum generated scale in the UV regime and gives support for the consistency of spontaneously broken gravity theories. (orig.)

The effect of glycogen phosphorolysis on basal glutaminergic transmission.

Science.gov (United States)

Mozrzymas, Jerzy; Szczęsny, Tomasz; Rakus, Darek

2011-01-14

Astrocytic glycogen metabolism sustains neuronal activity but its impact on basal glutamatergic synaptic transmission is not clear. To address this issue, we have compared the effect of glycogen breakdown inhibition on miniature excitatory postsynaptic currents (mEPSCs) in rat hippocampal pure neuronal culture (PNC) and in astrocyte-neuronal co-cultures (ANCC). Amplitudes of mEPSC in ANCC were nearly twice as large as in PNC with no difference in current kinetics. Inhibition of glycogen phosphorylase reduced mEPSC amplitude by roughly 40% in ANCC being ineffective in PNC. Altogether, these data indicate that astrocyte-neuronal interaction enhances basal mEPSCs in ANCC mainly due to astrocytic glycogen metabolism. Copyright © 2010 Elsevier Inc. All rights reserved.

Thoracoscopic modified pleural tent for spontaneous pneumothorax.

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Kawachi, Riken; Matsuwaki, Rie; Tachibana, Keisei; Karita, Shin; Nakazato, Yoko; Tanaka, Ryota; Nagashima, Yasushi; Takei, Hidefumi; Kondo, Haruhiko

2016-08-01

We developed a modified pleural tent (m-tent) procedure and used it in our hospital in almost 30 consecutive patients with spontaneous pneumothorax. The objective of this study was to clarify the feasibility and effectiveness of a thoracoscopic m-tent for the treatment of spontaneous pneumothorax. From July 2013 to November 2014, 107 patients with spontaneous pneumothorax were treated in our institution. Eighty-nine of these patients were analysed retrospectively. The inclusion criteria for thoracoscopic m-tent for spontaneous pneumothorax were multiple and widespread bullae, postoperative relapse and secondary spontaneous pneumothorax. The surgical procedures were usually performed through three ports. After bullectomy, an m-tent is made to strip the parietal pleura off the chest wall from about the level of the fourth or fifth rib to the apex, and two or three ligations are then applied to fix the pleural tent and lung parenchyma. Patients in whom an m-tent was not indicated underwent bullectomy plus coverage using absorbable materials. Twenty-seven patients underwent bullectomy plus m-tent (m-tent group) and 62 underwent bullectomy plus coverage over a staple line using an absorbable material such as a polyglycolic acid sheet or nitrocellulose sheet (coverage group). No severe postoperative complications were observed in either group. The m-tent and coverage groups showed significant differences in operation time (129 vs 86 min, mean), haemorrhage (12.8 vs 7.2 ml), postoperative hospital stay (3.7 vs 2.9 days) and postoperative painkiller intake (8.6 vs 6.8 days). Recurrence was observed in 1 (3.7%) and 2 patients (3.2%), respectively. The thoracoscopic m-tent procedure requires a longer operation, a longer hospital stay and greater painkiller intake. However, these differences are acceptable, and an m-tent should be considered as an option for pleural reinforcement in spontaneous pneumothorax, especially in patients who are complicated with severe pulmonary

[Bacterial vaginosis and spontaneous preterm birth].

Science.gov (United States)

Brabant, G

2016-12-01

To determine if bacterial vaginosis is a marker for risk of spontaneous preterm delivery and if its detection and treatment can reduce this risk. Consultation of the database Pubmed/Medline, Science Direct, and international guidelines of medical societies. Bacterial vaginosis (BV) is a dysbiosis resulting in an imbalance in the vaginal flora through the multiplication of anaerobic bacteria and jointly of a disappearance of well-known protective Lactobacilli. His diagnosis is based on clinical Amsel criteria and/or a Gram stain with establishment of the Nugent score. The prevalence of the BV extraordinarily varies according to ethnic and/or geographical origin (4-58 %), in France, it is close to 7 % in the first trimester of pregnancy (EL2). The link between BV and spontaneous premature delivery is low with an odds ratio between 1.5 and 2 in the most recent studies (EL3). Metronidazole or clindamycin is effective to treat BV (EL3). It is recommended to prescribe one of these antibiotics in the case of symptomatic BV (Professional Consensus). The testing associated with the treatment of BV in the global population showed no benefit in the prevention of the risk of spontaneous preterm delivery (EL2). Concerning low-risk asymptomatic population (defined by the absence of antecedent of premature delivery), it has been failed profit to track and treat the BV in the prevention of the risk of spontaneous preterm delivery (EL1). Concerning the high-risk population (defined by a history of preterm delivery), it has been failed profit to track and treat the VB in the prevention of the risk of spontaneous preterm delivery (EL3). However, in the sub population of patients with a history of preterm delivery occurred in a context of materno-fetal bacterial infection, there may be a benefit to detect and treat early and systematically genital infection, and in particular the BV (Professional Consensus). The screening and treatment of BV during pregnancy in asymptomatic low

Spontaneous Gamma Activity in Schizophrenia.

Science.gov (United States)

Hirano, Yoji; Oribe, Naoya; Kanba, Shigenobu; Onitsuka, Toshiaki; Nestor, Paul G; Spencer, Kevin M

2015-08-01

A major goal of translational neuroscience is to identify neural circuit abnormalities in neuropsychiatric disorders that can be studied in animal models to facilitate the development of new treatments. Oscillations in the gamma band (30-100 Hz) of the electroencephalogram have received considerable interest as the basic mechanisms underlying these oscillations are understood, and gamma abnormalities have been found in schizophrenia (SZ). Animal models of SZ based on hypofunction of the N-methyl-d-aspartate receptor (NMDAR) demonstrate increased spontaneous broadband gamma power, but this phenomenon has not been identified clearly in patients with SZ. To examine spontaneous gamma power and its relationship to evoked gamma oscillations in the auditory cortex of patients with SZ. We performed a cross-sectional study including 24 patients with chronic SZ and 24 matched healthy control participants at the Veterans Affairs Boston Healthcare System from January 1, 2009, through December 31, 2012. Electroencephalograms were obtained during auditory steady-state stimulation at multiple frequencies (20, 30, and 40 Hz) and during a resting state in 18 participants in each group. Electroencephalographic activity in the auditory cortex was estimated using dipole source localization. Auditory steady-state response (ASSR) measures included the phase-locking factor and evoked power. Spontaneous gamma power was measured as induced (non-phase-locked) gamma power in the ASSR data and as total gamma power in the resting-state data. The ASSR phase-locking factor was reduced significantly in patients with SZ compared with controls for the 40-Hz stimulation (mean [SD], 0.075 [0.028] vs 0.113 [0.065]; F1,46 = 6.79 [P = .012]) but not the 20- or the 30-Hz stimulation (0.042 [0.038] vs 0.043 [0.034]; F1,46 = 0.006 [P = .938] and 0.084 [0.040] vs 0.098 [0.050]; F1,46 = 1.605 [P = .212], respectively), repeating previous findings. The mean [SD] broadband-induced (30

Merkel Cell Carcinoma with Spontaneous Regression: A Case Report and Immunohistochemical Study

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Hitoshi Terui

2016-02-01

Full Text Available Merkel cell carcinoma (MCC is an aggressive neuroendocrine carcinoma that only rarely regresses spontaneously. Since little is known about the immunological mechanisms involved in the spontaneous regression of MCC, we describe a case of MCC with spontaneous regression and employed immunohistochemical staining for cytotoxic and immunosuppressive molecules to investigate possible mechanisms involved in the spontaneous regression of MCC. Interestingly, compared to conventional MCC, tumor-infiltrating lymphocytes in MCC with spontaneous regression contained higher numbers of CD8+ cells and granulysin-bearing cells and lower numbers of CD206+ cells. Our present study suggests one of the possible reasons for the spontaneous regression of MCC.

Spontaneous poisoning by Prosopis juliflora (Leguminosae) in sheep

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The aim of this paper is to describe the first report of clinical, epidemiological and pathological aspects of spontaneous poisoning by Prosopis juliflora in sheep. Of a total of 500 sheep at risk, two adult male sheep were affected; one died spontaneously and the other animal was examined, euthaniz...

Spontaneous Hypoglycemia After Islet Autotransplantation for Chronic Pancreatitis.

Science.gov (United States)

Lin, Yu Kuei; Faiman, Charles; Johnston, Philip C; Walsh, R Matthew; Stevens, Tyler; Bottino, Rita; Hatipoglu, Betul A

2016-10-01

Spontaneous hypoglycemia has been reported in patients after total pancreatectomy (TP) and islet autotransplantation (IAT) with maintained insulin independence. Details surrounding these events have not been well described. The objective of the study was to determine the frequency and characteristics of spontaneous hypoglycemia in patients undergoing TP-IAT and/or to ascertain predictive or protective factors of its development. This was an observational cohort study in 40 patients who underwent TP-IAT from August 2008 to May 2014, with a median follow-up of 34 months. The study was conducted at a single institution (Cleveland Clinic). Patients included recipients of TP-IAT. The intervention included small, frequent meals in those patients who developed spontaneous hypoglycemia. Incidence of spontaneous hypoglycemia development, characteristics of the patients developing hypoglycemia, and their response to small, frequent meals were measured. Six of 12 patients, who maintained insulin independence, developed spontaneous hypoglycemia. The episodes could be fasting, postprandial, and/or exercise associated, with the frequency ranging from two to three times daily to once every 1-2 weeks. All patients experienced at least one episode that required external assistance, glucagon administration, and/or emergent medical attention. Patients who developed hypoglycemia had a lower median age and tended to have a lower median islet equivalent/kg body weight but a higher median total islet equivalent, body mass index, and homeostatic model assessment for insulin resistance score. All patients who received small, frequent meal intervention had improvement in severity and/or frequency of the hypoglycemic episodes. Spontaneous hypoglycemia is prevalent after TP-IAT. Although the underlying pathophysiology responsible for these hypoglycemia events remains to be elucidated, small, frequent meal intervention is helpful in ameliorating this condition.

On spontaneous breakdown in Σ-models

International Nuclear Information System (INIS)

Ivanov, E.A.

1975-01-01

The group theory aspects of spontaneous breakdown in linear Σ-models are discussed. General conditions are formulated under which multiplet of group G (compact or noncompact) is suitable for constructing the Σ-model with a given subgroup of stability of vacuum. It is shown that the Σ-models of spontaneously broken space-time symmetries can be constructed in general only if some extra coordinates are introduced in addition to an ordinary 4-coordinate xsub(μ). The connection between Σ-models of internal symmetries and appropriate nonlinear realizations has also been investigated

Cavity enhanced rephased amplified spontaneous emission

International Nuclear Information System (INIS)

A Williamson, Lewis; J Longdell, Jevon

2014-01-01

Amplified spontaneous emission is usually treated as an incoherent noise process. Recent theoretical and experimental work using rephasing optical pulses has shown that rephased amplified spontaneous emission (RASE) is a potential source of wide bandwidth time-delayed entanglement. Due to poor echo efficiency the plain RASE protocol does not in theory achieve perfect entanglement. Experiments done to date show a very small amount of entanglement at best. Here we show that RASE can, in principle, produce perfect multimode time-delayed two mode squeezing when the active medium is placed inside a Q-switched cavity. (paper)

The influence of spontaneous activity on stimulus processing in primary visual cortex.

Science.gov (United States)

Schölvinck, M L; Friston, K J; Rees, G

2012-02-01

Spontaneous activity in the resting human brain has been studied extensively; however, how such activity affects the local processing of a sensory stimulus is relatively unknown. Here, we examined the impact of spontaneous activity in primary visual cortex on neuronal and behavioural responses to a simple visual stimulus, using functional MRI. Stimulus-evoked responses remained essentially unchanged by spontaneous fluctuations, combining with them in a largely linear fashion (i.e., with little evidence for an interaction). However, interactions between spontaneous fluctuations and stimulus-evoked responses were evident behaviourally; high levels of spontaneous activity tended to be associated with increased stimulus detection at perceptual threshold. Our results extend those found in studies of spontaneous fluctuations in motor cortex and higher order visual areas, and suggest a fundamental role for spontaneous activity in stimulus processing. Copyright © 2011. Published by Elsevier Inc.

Convergence of cranial visceral afferents within the solitary tract nucleus.

Science.gov (United States)

McDougall, Stuart J; Peters, James H; Andresen, Michael C

2009-10-14

Primary afferent axons within the solitary tract (ST) relay homeostatic information via glutamatergic synapses directly to second-order neurons within the nucleus of the solitary tract (NTS). These primary afferents arise from multiple organ systems and relay multiple sensory modalities. How this compact network organizes the flow of primary afferent information will shape central homeostatic control. To assess afferent convergence and divergence, we recorded ST-evoked synaptic responses in pairs of medial NTS neurons in horizontal brainstem slices. ST shocks activated EPSCs along monosynaptic or polysynaptic pathways. Gradations in shock intensity discriminated multiple inputs and stimulus recruitment profiles indicated that each EPSC was unitary. In 24 pairs, 75% were second-order neurons with 64% receiving one direct ST input with the remainder receiving additional convergent ST afferent inputs (22% two; 14% three monosynaptic ST-EPSCs). Some (34%) second-order neurons received polysynaptic EPSCs. Neurons receiving only higher-order inputs were uncommon (13%). Most ST-EPSCs were completely independent, but 4 EPSCs of a total of 81 had equal thresholds, highly correlated latencies, and synchronized synaptic failures consistent with divergence from a single source ST axon or from a common interneuron producing a pair of polysynaptic EPSCs. We conclude that ST afferent inputs are remarkably independent with little evidence of substantial shared information. Individual cells receive highly focused information from the viscera. Thus, afferent excitation of second-order NTS neurons is generally dominated by single visceral afferents and therefore focused on a single afferent modality and/or organ region.

New Perspectives on Spontaneous Brain Activity: Dynamic Networks and Energy Matter.

Science.gov (United States)

Tozzi, Arturo; Zare, Marzieh; Benasich, April A

2016-01-01

Spontaneous brain activity has received increasing attention as demonstrated by the exponential rise in the number of published article on this topic over the last 30 years. Such "intrinsic" brain activity, generated in the absence of an explicit task, is frequently associated with resting-state or default-mode networks (DMN)s. The focus on characterizing spontaneous brain activity promises to shed new light on questions concerning the structural and functional architecture of the brain and how they are related to "mind". However, many critical questions have yet to be addressed. In this review, we focus on a scarcely explored area, specifically the energetic requirements and constraints of spontaneous activity, taking into account both thermodynamical and informational perspectives. We argue that the "classical" definitions of spontaneous activity do not take into account an important feature, that is, the critical thermodynamic energetic differences between spontaneous and evoked brain activity. Spontaneous brain activity is associated with slower oscillations compared with evoked, task-related activity, hence it exhibits lower levels of enthalpy and "free-energy" (i.e., the energy that can be converted to do work), thus supporting noteworthy thermodynamic energetic differences between spontaneous and evoked brain activity. Increased spike frequency during evoked activity has a significant metabolic cost, consequently, brain functions traditionally associated with spontaneous activity, such as mind wandering, require less energy that other nervous activities. We also review recent empirical observations in neuroscience, in order to capture how spontaneous brain dynamics and mental function can be embedded in a non-linear dynamical framework, which considers nervous activity in terms of phase spaces, particle trajectories, random walks, attractors and/or paths at the edge of the chaos. This takes us from the thermodynamic free-energy, to the realm of "variational

Spontaneous Intracerebral Hemorrhage: Computed Tomographic Characteristics and Outcome

Directory of Open Access Journals (Sweden)

Aimara de la Caridad Vergara Santos

2015-12-01

Full Text Available Background: strokes are the third leading cause of death among adults and 10-15 % of them are due to spontaneous intracerebral hemorrhage. Objective: to characterize spontaneous intracerebral hemorrhage through computed tomography scan and its outcome. Methods: a case series study was conducted comprising patients diagnosed with spontaneous intracerebral hemorrhage admitted to the Arnaldo Milián Castro Provincial University Hospital in Villa Clara from January 2009 to January 2010. Tomographic variables of interest were derived from evaluation of spontaneous intracerebral hematomas. Results: fifty-nine cases of spontaneous intracerebral hemorrhage were studied, 23 were located in lobar regions, 4 had severe midline shift, and 2 showed volume greater than 80 ml. Eight out of eleven with extension into the ventricular system had an unfavorable outcome. Among those with thalamic hemorrhage, patients with diameter larger than 4cm and extension into the ventricular system died. Patients with putaminal hemorrhage larger than 4 cm and posterior fossa hematoma with hydrocephalus had a poor outcome, as well as most individuals (55 with other mass effects. Most lobar hematomas (14 out of 23 had a satisfactory outcome, unlike cerebellar and brainstem hematomas. Conclusions: tomographic variables that had a negative impact on the outcome were: volume greater than 80 ml, severe midline shift, diameter larger than 4 cm, extension into the ventricular system, hydrocephalus, other signs of mass effect and brainstem location.

Spontaneous perseverative turning in rats with radiation-induced hippocampal damage

International Nuclear Information System (INIS)

Mickley, G.A.; Ferguson, J.L.; Nemeth, T.J.; Mulvihill, M.A.; Alderks, C.E.

1989-01-01

This study found a new behavioral correlate of lesions specific to the dentate granule cell layer of the hippocampus: spontaneous perseverative turning. Irradiation of a portion of the neonatal rat cerebral hemispheres produced hypoplasia of the granule cell layer of the hippocampal dentate gyrus while sparing the rest of the brain. Radiation-induced damage to the hippocampal formation caused rats placed in bowls to spontaneously turn in long, slow bouts without reversals. Irradiated subjects also exhibited other behaviors characteristic of hippocampal damage (e.g., perseveration in spontaneous exploration of the arms of a T-maze, retarded acquisition of a passive avoidance task, and increased horizontal locomotion). These data extend previously reported behavioral correlates of fascia dentata lesions and suggest the usefulness of a bout analysis of spontaneous bowl turning as a measure of nondiscrete-trial spontaneous alternation and a sensitive additional indicator of radiation-induced hippocampal damage

The effects of age and divided attention on spontaneous recognition.

Science.gov (United States)

Anderson, Benjamin A; Jacoby, Larry L; Thomas, Ruthann C; Balota, David A

2011-05-01

Studies of recognition typically involve tests in which the participant's memory for a stimulus is directly questioned. There are occasions however, in which memory occurs more spontaneously (e.g., an acquaintance seeming familiar out of context). Spontaneous recognition was investigated in a novel paradigm involving study of pictures and words followed by recognition judgments on stimuli with an old or new word superimposed over an old or new picture. Participants were instructed to make their recognition decision on either the picture or word and to ignore the distracting stimulus. Spontaneous recognition was measured as the influence of old vs. new distracters on target recognition. Across two experiments, older adults and younger adults placed under divided-attention showed a greater tendency to spontaneously recognize old distracters as compared to full-attention younger adults. The occurrence of spontaneous recognition is discussed in relation to ability to constrain retrieval to goal-relevant information.

Association between Nutritional Status with Spontaneous Abortion

Directory of Open Access Journals (Sweden)

Rahimeh Ahmadi

2016-11-01

Full Text Available Background: Spontaneous abortion is the most common adverse pregnancy outcome. We aimed to investigate a possible link between nutrient deficiencies and the risk of spontaneous abortion. Materials and Methods: This case-control study included the case group (n=331 experiencing a spontaneous abortion before 14 weeks of pregnancy and the control group (n=331 who were healthy pregnant women over 14 weeks of pregnancy. The participants filled out Food Frequency Questionnaire (FFQ, in which they reported their frequency of consumption for a given serving of each food item during the past three months, on a daily, weekly or monthly basis. The reported frequency for each food item was converted to a daily intake. Then, consumption of nutrients was compared between the two groups. Results: There are significant differences between the two groups regarding consumed servings/day of vegetables, bread and cereal, meat, poultry, fish, eggs, beans, fats, oils and dairy products (P=0.012, P<0.001, P=0.004, P<0.001, P=0.019, respectively. There are significant differences between the two groups in all micronutrient including folic acid, iron, vitamin C, vitamin B6, vitamin B12 and zinc (P<0.001. Conclusion: Poor nutrientions may be correlated with increased risk of spontaneous abortion

Simulating spontaneously generated coherence in a four-level atomic system

International Nuclear Information System (INIS)

Li Aijun; Gao Jinyue; Wu Jinhui; Wang Lei

2005-01-01

We study the spontaneous emission property of a four-level atomic system driven by two coherent fields. By numerical calculations in the bare state picture, we show that such interesting phenomena as extremely narrow peaks and spontaneous emission quenching can be realized, which are well understood by qualitative explanations in the partially and fully dressed state pictures. Especially, this coherently driven atomic system has two close-lying levels in the partially dressed state picture so that spontaneously generated coherence arises. Using our considered scheme it is feasible to carry out experiments based on spontaneously generated coherence because all rigorous requirements have been avoided in the bare state picture

Interprofessional learning, impression management, and spontaneity in the acute healthcare setting.

Science.gov (United States)

Bell, Elaine; McAllister, Sue; Ward, Paul R; Russell, Alison

2016-09-01

Spontaneous learning is integral to definitions of interprofessional learning (IPL) because it has been suggested that spontaneous learning can be deeply connected with the work that people do in collaboration with colleagues via their professional networks. However, its nature and the processes involved are not well understood. Goffman's theory of impression management offers a useful theoretical framework to consider the way in which interaction in the workplace connects to spontaneous learning. This article explores the current literature to investigate the usefulness of this framework to better understand and identify spontaneous learning in the workplace. Aspects such as the connections between spontaneous learning occurring in formal and informal work activities, the spaces in which it occurs, and the influence of professional networking are considered. It is proposed that research directed to developing a better understanding of the nature of spontaneous learning in IPL will assist in connecting this learning to formal IPL curricula, enhancing IPL and patient outcomes.

Spontaneity and Equilibrium III: A History of Misinformation

Science.gov (United States)

Raff, Lionel M.

2014-01-01

Necessary and sufficient criteria for reaction spontaneity in a given direction and for spontaneity of finite transformations in single-reaction, closed systems are developed. The criteria are general in that they hold for reactions conducted under either conditions of constant T and p or constant T and V. These results are illustrated using a…

Spontaneous Coronary Artery Dissection following Topical Hormone Replacement Therapy

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Alexander L. Pan

2012-01-01

Full Text Available Spontaneous coronary artery dissection is a rare condition, usually presenting as an acute coronary syndrome, and is often seen in states associated with high systemic estrogen levels such as pregnancy or oral contraceptive use. While topical hormonal replacement therapy may result in increased estrogen levels similar to those documented with oral contraceptive use, there are no reported cases of spontaneous coronary dissection with topical hormonal replacement therapy. We describe a 53-year-old female who developed two spontaneous coronary dissections while on topical hormonal replacement therapy. The patient had no other risk factors for coronary dissection. After withdrawal from topical hormonal therapy, our patient has done well and has not had recurrent coronary artery dissections over a one-year follow-up period. The potential contributory role of topical hormonal therapy as a cause of spontaneous coronary dissection should be recognized.

Spontaneous Rotational Inversion in Phycomyces

KAUST Repository

Goriely, Alain

2011-03-01

The filamentary fungus Phycomyces blakesleeanus undergoes a series of remarkable transitions during aerial growth. During what is known as the stagea IV growth phase, the fungus extends while rotating in a counterclockwise manner when viewed from above (stagea IVa) and then, while continuing to grow, spontaneously reverses to a clockwise rotation (stagea IVb). This phase lasts for 24-48Ah and is sometimes followed by yet another reversal (stageAIVc) before the overall growth ends. Here, we propose a continuum mechanical model of this entire process using nonlinear, anisotropic, elasticity and show how helical anisotropy associated with the cell wall structure can induce spontaneous rotation and, under appropriate circumstances, the observed reversal of rotational handedness. © 2011 American Physical Society.

Validation of second trimester miscarriages and spontaneous deliveries

DEFF Research Database (Denmark)

Sundtoft, Iben Blaabjerg; Sneider, Kirstine; Christiansen, Ole Bjarne

2015-01-01

OBJECTIVE: To validate the diagnosis of second trimester miscarriages/deliveries (16+0 weeks to 27+6 weeks of gestation) recorded as miscarriages in the Danish National Patient Registry or spontaneous deliveries in the Danish Medical Birth Registry, and asses the validity of risk factors, pregnancy...... information and calculated positive predictive values of the registry diagnoses stratified by type of registry, as well as sensitivity, specificity, positive predictive value, and kappa coefficients of risk factors, pregnancy complications, and cerclage. RESULTS: Miscarriage/spontaneous delivery in the second......-based information on pregnancy complications need to be improved. We recommend that all pregnancies ending spontaneously beyond the first trimester are included in the national birth registry and described by appropriate variables....

Detection of target phonemes in spontaneous and read speech

NARCIS (Netherlands)

Mehta, G.; Cutler, A.

1988-01-01

Although spontaneous speech occurs more frequently in most listeners' experience than read speech, laboratory studies of human speech recognition typically use carefully controlled materials read from a script. The phonological and prosodic characteristics of spontaneous and read speech differ

Factors Analysis of Spontaneous Abortion after Thawed-vitrified Blastocysts Transfer

Institute of Scientific and Technical Information of China (English)

Dong YANG; Zheng-yi SUN; Cheng-yan DENG; Qi YU; Fang-fang HE

2008-01-01

Objective To investigate the factors resulting in spontaneous abortion after transferring frozen-thawing blastocysts. Methods A total of 108 cases transferring vitrified blastocysts were divided into two groups: abortion group (n =20) and ongoing group (n=88). Cytogenetic analysis of apoblemas was performed in 12 cases of the abortion.Results The overall spontaneous abortion rate was 18.50%(20/108) and the early spontaneous rate was 16.67%(18/108). ,4 significant difference in maternal age was observed (abortion group: 33.3±4.0 years, ongoing group: 31.0±3.6 years, P=0.02). No difference in other parameters was found. Cytogenetic analysis of apoblemas was obtained for 12 cases, and 2 specimens were contaminated. Seven of ten patients had abnormal karyotypes. Conclusion The underlying cause of spontaneous abortion after transferring frozen thawing blastocysts appears to be abnormal karyotypes.Advancing maternal age seems to increase the risk of spontaneous abortion.

Factors Associated with Spontaneous Clearance of Hepatitis C Virus in Chinese Population

Directory of Open Access Journals (Sweden)

Fei Kong

2014-01-01

Full Text Available Hepatitis C virus (HCV infections spontaneously clear in approximately 15–45% of infected individuals. Factors which influence spontaneous HCV clearance remain to be identified. The purpose of the present study was to identify variables associated with spontaneous HCV clearance in a referred population of Chinese patients. The prevalence of host, viral, and environmental factors known to influence the outcome of HCV infections was compared in 92 HCV spontaneous clearance subjects and 318 HCV persistent infection subjects. Univariate and multivariate analyses were performed to identify those factors associated with spontaneous HCV clearance. In univariate analysis, female gender, a history of icteric hepatitis, serologic evidence of concurrent HBV infection, and rs12979860 CC genotype were positively associated with spontaneous HCV clearance, while alcohol consumption was negatively associated with clearance. In multivariate analysis, female gender, a history of icteric hepatitis, concurrent HBV infection, and rs12979860 CC genotype remained independent variables associated with spontaneous HCV clearance. Spontaneous HCV clearance is more likely to occur in females, subjects with a history of icteric hepatitis, HBV coinfections, and those with the rs12979860 CC genotype.

Bilateral spontaneous rupture of flexor digitorum profundus tendons.

LENUS (Irish Health Repository)

O'Sullivan, S T

2012-02-03

Spontaneous tendon rupture is an unusual condition usually associated with underlying disease processes such as rheumatoid arthritis, chronic renal failure or bony abnormalities of the hand. We report a case of spontaneous, non-concurrent bilateral rupture of flexor profundus tendons in an otherwise healthy individual. Treatment was successful and consisted of a two-stage reconstruction of the ruptured tendon.

Bilateral spontaneous pneumothorax with pulmonary metastases of synovial sarcoma

International Nuclear Information System (INIS)

Matushita, J.P.K.; Azevedo, C.M. de

1989-01-01

The association of bilateral spontaneous pneumothorax with pulmonary tumor is uncommon and with pulmonary metastases is rare. The clinical and radiological features of bilateral spontaneous pneumothorax from a synovial sarcoma in a 14 years old boy are described. (author) [pt

Visually Evoked Spiking Evolves While Spontaneous Ongoing Dynamics Persist

DEFF Research Database (Denmark)

Huys, Raoul; Jirsa, Viktor K; Darokhan, Ziauddin

2016-01-01

attractor. Its existence guarantees that evoked spiking return to the spontaneous state. However, the spontaneous ongoing spiking state and the visual evoked spiking states are qualitatively different and are separated by a threshold (separatrix). The functional advantage of this organization...

Tooth display and lip position during spontaneous and posed smiling in adults.

Science.gov (United States)

Van Der Geld, Pieter; Oosterveld, Paul; Berge, Stefaan J; Kuijpers-Jagtman, Anne M

2008-08-01

To analyze differences in tooth display, lip-line height, and smile width between the posed smiling record, traditionally produced for orthodontic diagnosis, and the spontaneous (Duchenne) smile of joy. The faces of 122 male participants were each filmed during spontaneous and posed smiling. Spontaneous smiles were elicited through the participants watching a comical movie. Maxillary and mandibular lip-line heights, tooth display, and smile width were measured using a digital videographic method for smile analysis. Paired sample t-tests were used to compare measurements of posed and spontaneous smiling. Maxillary lip-line heights during spontaneous smiling were significantly higher than during posed smiling. Compared to spontaneous smiling, tooth display in the (pre)molar area during posed smiling decreased by up to 30%, along with a significant reduction of smile width. During posed smiling, also mandibular lip-line heights changed and the teeth were more covered by the lower lip than during spontaneous smiling. Reduced lip-line heights, tooth display, and smile width on a posed smiling record can have implications for the diagnostics of lip-line height, smile arc, buccal corridors, and plane of occlusion. Spontaneous smiling records next to posed smiling records are therefore recommended for diagnostic purposes. Because of the dynamic nature of spontaneous smiling, it is proposed to switch to dynamic video recording of the smile.

Generation of folliculogenic human epithelial stem cells from induced pluripotent stem cells

Science.gov (United States)

Yang, Ruifeng; Zheng, Ying; Burrows, Michelle; Liu, Shujing; Wei, Zhi; Nace, Arben; Guo, Wei; Kumar, Suresh; Cotsarelis, George; Xu, Xiaowei

2014-01-01

Epithelial stem cells (EpSCs) in the hair follicle bulge are required for hair follicle growth and cycling. The isolation and propagation of human EpSCs for tissue engineering purposes remains a challenge. Here we develop a strategy to differentiate human iPSCs (hiPSCs) into CD200+/ITGA6+ EpSCs that can reconstitute the epithelial components of the hair follicle and interfollicular epidermis. The hiPSC-derived CD200+/ITGA6+ cells show a similar gene expression signature as EpSCs directly isolated from human hair follicles. Human iPSC-derived CD200+/ITGA6+ cells are capable of generating all hair follicle lineages including the hair shaft, and the inner and outer root sheaths in skin reconstitution assays. The regenerated hair follicles possess a KRT15+ stem cell population and produce hair shafts expressing hair-specific keratins. These results suggest an approach for generating large numbers of human EpSCs for tissue engineering and new treatments for hair loss, wound healing and other degenerative skin disorders.

Spontaneous regression of metastatic Merkel cell carcinoma.

LENUS (Irish Health Repository)

Hassan, S J

2010-01-01

Merkel cell carcinoma is a rare aggressive neuroendocrine carcinoma of the skin predominantly affecting elderly Caucasians. It has a high rate of local recurrence and regional lymph node metastases. It is associated with a poor prognosis. Complete spontaneous regression of Merkel cell carcinoma has been reported but is a poorly understood phenomenon. Here we present a case of complete spontaneous regression of metastatic Merkel cell carcinoma demonstrating a markedly different pattern of events from those previously published.

An unusual case of spontaneous esophagopleural fistula

OpenAIRE

Manoranjan Dash; Thitta Mohanty; Jyoti Patnaik; Narayan Mishra; Saswat Subhankar; Priyadarsini Parida

2017-01-01

Esophago-pleural fistula (EPF) is an uncommon condition, despite of an anatomical proximity of these structures. Causes of EPF include pneumonectomy for suppurative or tubercular disease of lung and carcinoma lung, malignancy of esophagus. Benign EPF is rare and may be due to trauma or infection. The most common infectious cause is tuberculosis. Spontaneous development of fistula between esophagus and pleura is rarely described in literature. We, hereby present a spontaneous case of such a ra...

Hematome Extra - Dural Rachidien Spontane

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Cl. Gros

1967-01-01

Full Text Available Four personal cases of Spontaneous Spinal Epidurdl Hemerrhage are Reported. And 29 additional cases have been analysed by reviewing the literature. The clinical radiologcal and surgical aspects were discussed.

Spontaneous pneumothorax after upper mantle radiation therapy for Hodgkin disease

International Nuclear Information System (INIS)

Paszat, L.; Basrur, V.; Tadros, A.

1986-01-01

Between 1967 and 1981, 158 of 256 consecutive adult patients received upper mantle (UM) radiation therapy as part of initial treatment of Hodgkin disease at the Hamilton Regional Cancer Centre. Chemotherapy was also part of the initial treatment in 21 of 158 patients who received UM radiation therapy. Spontaneous pneumothorax was observed in six of 158 patients during remission after UM radiation therapy in this series. Three cases were incidental findings on follow-up radiographs, but three other patients were seen initially with symptoms of spontaneous pneumothorax. The entity occurred in three of 21 patients (14%) treated with UM radiation therapy and chemotherapy, and in three of 137 (2%) treated with UM radiation therapy (P < .05). Within the range of UM doses (3,500-4,000 cGy in 4 weeks), higher dose was not associated with higher risk of spontaneous pneumothorax. Although these cases of spontaneous pneumothorax are clustered in an age range classic for this entity, the incidence of spontaneous pneumothorax in this group of patients is higher than the anticipated lifetime incidence of 1:500 for the general population. This risk of spontaneous pneumothorax after UM radiation therapy may be even higher in patients who also receive chemotherapy

The Environmental Neurotoxicant PCB 95 Promotes Synaptogenesis via Ryanodine Receptor-Dependent miR132 Upregulation

Science.gov (United States)

Lesiak, Adam; Zhu, Mingyan; Chen, Hao; Appleyard, Suzanne M.; Impey, Soren; Wayman, Gary A.

2014-01-01

Non–dioxin-like (NDL) polychlorinated biphenyls (PCBs) are widespread environmental contaminants linked to neuropsychological dysfunction in children. NDL PCBs increase spontaneous Ca2+ oscillations in neurons by stabilizing ryanodine receptor (RyR) calcium release channels in the open configuration, which results in CREB-dependent dendritic outgrowth. In this study, we address the question of whether activation of CREB by NDL PCBs also triggers dendritic spine formation. Nanomolar concentrations of PCB 95, a NDL congener with potent RyR activity, significantly increased spine density and the frequency of miniature EPSCs in primary dissociated rat hippocampal cultures coincident with upregulation of miR132. Inhibition of RyR, CREB, or miR132 as well as expression of a mutant p250GAP cDNA construct that is not suppressed by miR132 blocked PCB 95 effects on spines and miniature EPSCs. PCB 95 also induced spine formation via RyR- and miR132-dependent mechanisms in hippocampal slice cultures. These data demonstrate a novel mechanism of PCB developmental neurotoxicity whereby RyR sensitization modulates spine formation and synaptogenesis via CREB-mediated miR132 upregulation, which in turn suppresses the translation of p250GAP, a negative regulator of synaptogenesis. In light of recent evidence implicating miR132 dysregulation in Rett syndrome and schizophrenia, these findings identify NDL PCBs as potential environmental risk factors for neurodevelopmental disorders. PMID:24431430

Synthetic ciguatoxin CTX 3C induces a rapid imbalance in neuronal excitability.

Science.gov (United States)

Martín, Victor; Vale, Carmen; Hirama, Masahiro; Yamashita, Shuji; Rubiolo, Juan Andrés; Vieytes, Mercedes R; Botana, Luis M

2015-06-15

Ciguatera is a human global disease caused by the consumption of contaminated fish that have accumulated ciguatoxins (CTXs), sodium channel activator toxins. Symptoms of ciguatera include neurological alterations such as paraesthesiae, dysaesthesiae, depression, and heightened nociperception, among others. An important issue to understand these long-term neurological alterations is to establish the role that changes in activity produced by CTX 3C represent to neurons. Here, the effects of synthetic ciguatoxin CTX 3C on membrane potential, spontaneous spiking, and properties of synaptic transmission in cultured cortical neurons of 11-18 days in vitro (DIV) were evaluated using electrophysiological approaches. CTX 3C induced a large depolarization that decreased neuronal firing and caused a rapid inward tonic current that was primarily GABAergic. Moreover, the toxin enhanced the amplitude of miniature postsynaptic inhibitory currents (mIPSCs), whereas it decreased the amplitude of miniature postsynaptic excitatory currents (mEPSCs). The frequency of mIPSCs increased, whereas the frequency of mEPSCs remained unaltered. We describe, for the first time, that a rapid membrane depolarization caused by CTX 3C in cortical neurons activates mechanisms that tend to suppress electrical activity by shifting the balance between excitatory and inhibitory synaptic transmission toward inhibition. Indeed, these results suggest that the acute effects of CTX on synaptic transmission could underlie some of the neurological symptoms caused by ciguatera in humans.

Computed tomography in the assessment of idiopathic spontaneous pneumothorax

International Nuclear Information System (INIS)

Kim, Sang Jin; Lee, Doo Yun; Kim, Hyung Jung

1991-01-01

It is well known that idiopathic spontaneous pneumothorax is caused by rupture of the subpleural bleb and presents difficulty in exact detection and localization of the bleb with plain chest X - ray alone. The authors performed chest CT scans for accurate diagnosis of bleb that would act as a guide for optimal management of idiopathic spontaneous pneumothorax patients in order to prevent recurrent pneumothorax. We could detect blebs in 93 % (26/28) of the patients with idiopathic spontaneous pneumothorax, and 68 % (19/ 28) of the patient had bilateral blebs. Sensitivity was 0.63, and false negative was 37% (37/100) of the blebs, and 51% (19/37) of these 37 false negative cases were ruptured blebs. Only 7 % (2/28) of the patients had a single bleb. The authors concluded that CT is a useful method of study for optimal management of idiopathic spontaneous pneumothorax patients

Pain-related increase of excitatory transmission and decrease of inhibitory transmission in the central nucleus of the amygdala are mediated by mGluR1

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Neugebauer Volker

2010-12-01

mechanism. An mGluR5 antagonist (MTEP inhibited both excitatory and inhibitory transmission in slices from normal and from arthritic rats. The analysis of spontaneous and miniature EPSCs and IPSCs showed that mGluR1 acted presynaptically whereas mGluR5 had postsynaptic effects. In conclusion, mGluR1 rather than mGluR5 can account for the pain-related changes of excitatory and inhibitory synaptic transmission in the CeLC through a mechanism that involves inhibition of inhibitory transmission (disinhibition.

CaMKII Regulates Synaptic NMDA Receptor Activity of Hypothalamic Presympathetic Neurons and Sympathetic Outflow in Hypertension.

Science.gov (United States)

Li, De-Pei; Zhou, Jing-Jing; Zhang, Jixiang; Pan, Hui-Lin

2017-11-01

NMDAR activity in the hypothalamic paraventricular nucleus (PVN) is increased and critically involved in heightened sympathetic vasomotor tone in hypertension. Calcium/calmodulin-dependent protein kinase II (CaMKII) binds to and modulates NMDAR activity. In this study, we determined the role of CaMKII in regulating NMDAR activity of PVN presympathetic neurons in male spontaneously hypertensive rats (SHRs). NMDAR-mediated EPSCs and puff NMDA-elicited currents were recorded in spinally projecting PVN neurons in SHRs and male Wistar-Kyoto (WKY) rats. The basal amplitude of evoked NMDAR-EPSCs and puff NMDA currents in retrogradely labeled PVN neurons were significantly higher in SHRs than in WKY rats. The CaMKII inhibitor autocamtide-2-related inhibitory peptide (AIP) normalized the increased amplitude of NMDAR-EPSCs and puff NMDA currents in labeled PVN neurons in SHRs but had no effect in WKY rats. Treatment with AIP also normalized the higher frequency of NMDAR-mediated miniature EPSCs of PVN neurons in SHRs. CaMKII-mediated phosphorylation level of GluN2B serine 1303 (S1303) in the PVN, but not in the hippocampus and frontal cortex, was significantly higher in SHRs than in WKY rats. Lowering blood pressure with celiac ganglionectomy in SHRs did not alter the increased level of phosphorylated GluN2B S1303 in the PVN. In addition, microinjection of AIP into the PVN significantly reduced arterial blood pressure and lumbar sympathetic nerve discharges in SHRs. Our findings suggest that CaMKII activity is increased in the PVN and contributes to potentiated presynaptic and postsynaptic NMDAR activity to elevate sympathetic vasomotor tone in hypertension. SIGNIFICANCE STATEMENT Heightened sympathetic vasomotor tone is a major contributor to the development of hypertension. Although glutamate NMDA receptor (NMDAR)-mediated excitatory drive in the hypothalamus plays a critical role in increased sympathetic output in hypertension, the molecular mechanism involved in

Atypical development of spontaneous social cognition in autism spectrum disorders.

Science.gov (United States)

Senju, Atsushi

2013-02-01

Individuals with autism spectrum disorders (ASD) have profound impairment in the development of social interaction and communication. However, it is also known that some 'high-functioning' individuals with ASD show apparently typical capacity to process social information in a controlled experimental settings, despite their difficulties in daily life. The current paper overviews the spontaneous social cognition, spontaneous processing of social information in the absence of explicit instruction or task demand, in individuals with ASD. Three areas of the researches, false belief attribution, imitation/mimicry, and eye gaze processing, have been reviewed. The literatures suggest that high-functioning individuals with ASD (a) do not spontaneously attribute false belief to others, even though they can easily do so when explicitly instructed, (b) can imitate others' goal-directed actions under explicit instruction and show spontaneous mimicry of others' actions when they attend to the action, but are less likely to show spontaneous mimicry without the task structure to navigate attention to others' action and (c) can process others' gaze direction and shift attention to others' gaze directions, but fail to spontaneously attend to another person's eyes in social and communicative context, and less likely to be prompted to respond in response to perceived eye contact. These results are consistent with the claim that individuals with ASD do not spontaneously attend to socially relevant information, even though they can easily process the same information when their attention is navigated towards it. Copyright © 2012 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Coherent spontaneous radiation from highly bunched electron beams

International Nuclear Information System (INIS)

Berryman, K.W.; Crosson, E.R.; Ricci, K.N.

1995-01-01

Coherent spontaneous radiation has now been observed in several FELs, and is a subject of great importance to the design of self-amplified spontaneous emission (SASE) devices. We report observations of coherent spontaneous radiation in both FIREFLY and the mid-infrared FEL at the Stanford Picosecond FEL Center. Coherent emission has been observed at wavelengths as short as 5 microns, and enhancement over incoherent levels by as much as a factor of 4x10 4 has been observed at longer wavelengths. The latter behavior was observed at 45 microns in FIREFLY with short bunches produced by off-peak acceleration and dispersive compression. We present temporal measurements of the highly bunched electron distributions responsible for the large enhancements, using both transition radiation and energy-phase techniques

Planning for spontaneous evacuation during a radiological emergency

International Nuclear Information System (INIS)

Johnson, J.H. Jr.

1984-01-01

The Federal Emergency Management Agency's (FEMA's) radiological emergency preparedness program ignores the potential problem of spontaneous evacuation during a nuclear reactor accident. To show the importance of incorporating the emergency spatial behaviors of the population at risk in radiological emergency preparedness and response plans, this article presents empirical evidence that demonstrates the potential magnitude and geographic extent of spontaneous evacuation in the event of an accident at the Long Island Lighting Company's Shoreham Nuclear Power Station. The results indicate that, on the average, 39% of the population of Long Island is likely to evacuate spontaneously and thus to cast an evacuation shadow extending at least 25 miles beyond the plant. On the basis of these findings, necessary revisions to FEMA's radiological emergency preparedness program are outlined

Spontaneous ischaemic stroke lesions in a dog brain

DEFF Research Database (Denmark)

Thomsen, Barbara Blicher; Gredal, Hanne; Nielsen, Martin Wirenfeldt

2017-01-01

Background Dogs develop spontaneous ischaemic stroke with a clinical picture closely resembling human ischaemic stroke patients. Animal stroke models have been developed, but it has proved difficult to translate results obtained from such models into successful therapeutic strategies in human...... stroke patients. In order to face this apparent translational gap within stroke research, dogs with ischaemic stroke constitute an opportunity to study the neuropathology of ischaemic stroke in an animal species. Case presentation A 7 years and 8 months old female neutered Rottweiler dog suffered....../macrophages and astrocytes. Conclusions The neuropathological changes reported in the present study were similar to findings in human patients with ischaemic stroke. The dog with spontaneous ischaemic stroke is of interest as a complementary spontaneous animal model for further neuropathological studies....

ANTISPERM ANTIBODY IS A POSSIBLE CAUSE OF SPONTANEOUS ABORTION

Institute of Scientific and Technical Information of China (English)

XUChong; CHENFu; LIULi; ZHAOFei-Sha

1989-01-01

To clarify the possible correlation between antisperm antibodies (ASA) and spontaneous abortion, 68 women, aged 23-37, experienced 2-9 times of spontaneous abortion were tested for ASA by ELISA. 38 fertile women, aged 24-40, without history of abortion were employed as control.

Spontaneous emission control in a tunable hybrid photonic system

NARCIS (Netherlands)

Frimmer, M.; Koenderink, A.F.

2013-01-01

We experimentally demonstrate control of the rate of spontaneous emission in a tunable hybrid photonic system that consists of two canonical building blocks for spontaneous emission control, an optical antenna and a mirror, each providing a modification of the local density of optical states (LDOS).

Quark potential of spontaneous strings

International Nuclear Information System (INIS)

German, G.; Kleinert, H.

1989-01-01

The authors present some recent developments in string models with an extrinsic curvature term in action. Particular emphasis is placed upon the static quark potential and on the thermal deconfinement properties of spontaneous strings

Abolishment of Spontaneous Flight Turns in Visually Responsive Drosophila.

Science.gov (United States)

Ferris, Bennett Drew; Green, Jonathan; Maimon, Gaby

2018-01-22

Animals react rapidly to external stimuli, such as an approaching predator, but in other circumstances, they seem to act spontaneously, without any obvious external trigger. How do the neural processes mediating the execution of reflexive and spontaneous actions differ? We studied this question in tethered, flying Drosophila. We found that silencing a large but genetically defined set of non-motor neurons virtually eliminates spontaneous flight turns while preserving the tethered flies' ability to perform two types of visually evoked turns, demonstrating that, at least in flies, these two modes of action are almost completely dissociable. Copyright © 2017 Elsevier Ltd. All rights reserved.

From a distance: implications of spontaneous self-distancing for adaptive self-reflection.

Science.gov (United States)

Ayduk, Ozlem; Kross, Ethan

2010-05-01

Although recent experimental work indicates that self-distancing facilitates adaptive self-reflection, it remains unclear (a) whether spontaneous self-distancing leads to similar adaptive outcomes, (b) how spontaneous self-distancing relates to avoidance, and (c) how this strategy impacts interpersonal behavior. Three studies examined these issues demonstrating that the more participants spontaneously self-distanced while reflecting on negative memories, the less emotional (Studies 1-3) and cardiovascular (Study 2) reactivity they displayed in the short term. Spontaneous self-distancing was also associated with lower emotional reactivity and intrusive ideation over time (Study 1). The negative association between spontaneous self-distancing and emotional reactivity was mediated by how participants construed their experience (i.e., less recounting relative to reconstruing) rather than avoidance (Studies 1-2). In addition, spontaneous self-distancing was associated with more problem-solving behavior and less reciprocation of negativity during conflicts among couples in ongoing relationships (Study 3). Although spontaneous self-distancing was empirically related to trait rumination, it explained unique variance in predicting key outcomes. 2010 APA, all rights reserved

Spontaneous Hall effect in a chiral p-wave superconductor

Science.gov (United States)

Furusaki, Akira; Matsumoto, Masashige; Sigrist, Manfred

2001-08-01

In a chiral superconductor with broken time-reversal symmetry a ``spontaneous Hall effect'' may be observed. We analyze this phenomenon by taking into account the surface properties of a chiral superconductor. We identify two main contributions to the spontaneous Hall effect. One contribution originates from the Bernoulli (or Lorentz) force due to spontaneous currents running along the surfaces of the superconductor. The other contribution has a topological origin and is related to the intrinsic angular momentum of Cooper pairs. The latter can be described in terms of a Chern-Simons-like term in the low-energy field theory of the superconductor and has some similarities with the quantum Hall effect. The spontaneous Hall effect in a chiral superconductor is, however, nonuniversal. Our analysis is based on three approaches to the problem: a self-consistent solution of the Bogoliubov-de Gennes equation, a generalized Ginzburg-Landau theory, and a hydrodynamic formulation. All three methods consistently lead to the same conclusion that the spontaneous Hall resistance of a two-dimensional superconducting Hall bar is of order h/(ekFλ)2, where kF is the Fermi wave vector and λ is the London penetration depth; the Hall resistance is substantially suppressed from a quantum unit of resistance. Experimental issues in measuring this effect are briefly discussed.

An unusual case of spontaneous esophagopleural fistula.

Science.gov (United States)

Dash, Manoranjan; Mohanty, Thitta; Patnaik, Jyoti; Mishra, Narayan; Subhankar, Saswat; Parida, Priyadarsini

2017-01-01

Esophago-pleural fistula (EPF) is an uncommon condition, despite of an anatomical proximity of these structures. Causes of EPF include pneumonectomy for suppurative or tubercular disease of lung and carcinoma lung, malignancy of esophagus. Benign EPF is rare and may be due to trauma or infection. The most common infectious cause is tuberculosis. Spontaneous development of fistula between esophagus and pleura is rarely described in literature. We, hereby present a spontaneous case of such a rare entity in a middle-aged male.

Spontaneous intracranial epidural hematoma during rivaroxaban treatment

Energy Technology Data Exchange (ETDEWEB)

Ruschel, Leonardo Gilmone; Rego, Felipe Marques Monteiro do; Milano, Jeronimo Buzetti; Jung, Gustavo Simiano; Silva Junior, Luis Fernando; Ramina, Ricardo, E-mail: leonardoruschel@yahoo.com.br [Instituto de Neurologia de Curitiba (INC), Curitiba, PR (Brazil)

2016-11-15

According to our research, this is the first case described in the literature of spontaneous intracranial epidural hematoma secondary to the use of Xarelto®. Spontaneous intracranial epidural hematomas are rarely described in the literature. They are associated with infectious diseases of the skull, coagulation disorders, vascular malformations of the dura mater and metastasis to the skull. Long-term post-marketing monitoring and independent reports will probably detect the full spectrum of hemorrhagic complications of the use of rivaroxaban. (author)

Streptozotocin Inhibits Electrophysiological Determinants of Excitatory and Inhibitory Synaptic Transmission in CA1 Pyramidal Neurons of Rat Hippocampal Slices: Reduction of These Effects by Edaravone

Directory of Open Access Journals (Sweden)

Ting Ju

2016-12-01

Full Text Available Background: Streptozotocin (STZ has served as an agent to generate an Alzheimer's disease (AD model in rats, while edaravone (EDA, a novel free radical scavenger, has recently emerged as an effective treatment for use in vivo and vitro AD models. However, to date, these beneficial effects of EDA have only been clearly demonstrated within STZ-induced animal models of AD and in cell models of AD. A better understanding of the mechanisms of EDA may provide the opportunity for their clinical application in the treatment of AD. Therefore, the purpose of this study was to investigate the underlying mechanisms of STZ and EDA as assessed upon electrophysiological alterations in CA1 pyramidal neurons of rat hippocampal slices. Methods: Through measures of evoked excitatory postsynaptic currents (eEPSCs, AMPAR-mediated eEPSCs (eEPSCsAMPA, evoked inhibitory postsynaptic currents (eIPSCs, evoked excitatory postsynaptic current paired pulse ratio (eEPSC PPR and evoked inhibitory postsynaptic current paired pulse ratio (eIPSC PPR, it was possible to investigate mechanisms as related to the neurotoxicity of STZ and reductions in these effects by EDA. Results: Our results showed that STZ (1000 µM significantly inhibited peak amplitudes of eEPSCs, eEPSCsAMPA and eIPSCs, while EDA (1000 µM attenuated these STZ-induced changes at holding potentials ranging from -60mV to +40 mV for EPSCs and -60mV to +20 mV for IPSCs. Our work also indicated that mean eEPSC PPR were substantially altered by STZ, effects which were partially restored by EDA. In contrast, no significant effects upon eIPSC PPR were obtained in response to STZ and EDA. Conclusion: Our data suggest that STZ inhibits glutamatergic transmission involving pre-synaptic mechanisms and AMPAR, and that STZ inhibits GABAergic transmission by post-synaptic mechanisms within CA1 pyramidal neurons. These effects are attenuated by EDA.

Spontaneous and posed facial expression in Parkinson's disease.

Science.gov (United States)

Smith, M C; Smith, M K; Ellgring, H

1996-09-01

Spontaneous and posed emotional facial expressions in individuals with Parkinson's disease (PD, n = 12) were compared with those of healthy age-matched controls (n = 12). The intensity and amount of facial expression in PD patients were expected to be reduced for spontaneous but not posed expressions. Emotional stimuli were video clips selected from films, 2-5 min in duration, designed to elicit feelings of happiness, sadness, fear, disgust, or anger. Facial movements were coded using Ekman and Friesen's (1978) Facial Action Coding System (FACS). In addition, participants rated their emotional experience on 9-point Likert scales. The PD group showed significantly less overall facial reactivity than did controls when viewing the films. The predicted Group X Condition (spontaneous vs. posed) interaction effect on smile intensity was found when PD participants with more severe disease were compared with those with milder disease and with controls. In contrast, ratings of emotional experience were similar for both groups. Depression was positively associated with emotion rating but not with measures of facial activity. Spontaneous facial expression appears to be selectively affected in PD, whereas posed expression and emotional experience remain relatively intact.

Behavioral Modulation by Spontaneous Activity of Dopamine Neurons

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Toshiharu Ichinose

2017-12-01

Full Text Available Dopamine modulates a variety of animal behaviors that range from sleep and learning to courtship and aggression. Besides its well-known phasic firing to natural reward, a substantial number of dopamine neurons (DANs are known to exhibit ongoing intrinsic activity in the absence of an external stimulus. While accumulating evidence points at functional implications for these intrinsic “spontaneous activities” of DANs in cognitive processes, a causal link to behavior and its underlying mechanisms has yet to be elucidated. Recent physiological studies in the model organism Drosophila melanogaster have uncovered that DANs in the fly brain are also spontaneously active, and that this activity reflects the behavioral/internal states of the animal. Strikingly, genetic manipulation of basal DAN activity resulted in behavioral alterations in the fly, providing critical evidence that links spontaneous DAN activity to behavioral states. Furthermore, circuit-level analyses have started to reveal cellular and molecular mechanisms that mediate or regulate spontaneous DAN activity. Through reviewing recent findings in different animals with the major focus on flies, we will discuss potential roles of this physiological phenomenon in directing animal behaviors.

When do humans spontaneously adopt another's visuospatial perspective?

Science.gov (United States)

Freundlieb, Martin; Kovács, Ágnes M; Sebanz, Natalie

2016-03-01

Perspective-taking is a key component of social interactions. However, there is an ongoing controversy about whether, when and how instances of spontaneous visuospatial perspective-taking occur. The aim of this study was to investigate the underlying factors as well as boundary conditions that characterize the spontaneous adoption of another person's visuospatial perspective (VSP) during social interactions. We used a novel paradigm, in which a participant and a confederate performed a simple stimulus-response (SR) compatibility task sitting at a 90° angle to each other. In this set-up, participants would show a spatial compatibility effect only if they adopted the confederate's VSP. In a series of 5 experiments we found that participants reliably adopted the VSP of the confederate, as long as he was perceived as an intentionally acting agent. Our results therefore show that humans are able to spontaneously adopt the differing VSP of another agent and that there is a tight link between perspective-taking and performing actions together. The results suggest that spontaneous VSP-taking can effectively facilitate and speed up spatial alignment processes accruing from dynamic interactions in multiagent environments. (c) 2016 APA, all rights reserved).

Spontaneous Ovarian Hyperstimulation Syndrome in a Term Pregnancy

Directory of Open Access Journals (Sweden)

Aytekin Tokmak

2015-09-01

Full Text Available Spontaneous OHSS in a term pregnancy is extremely rare. The aim of this study is to present a case of spontaneous ovarian hyperstimulation syndrome (OHSS in a term pregnancy. A 29-year-old primigravida woman conceived spontaneously and was observed up until 35 weeks of gestation. During this time the patient had a normal pregnancy with normal ovaries. She applied to the current clinic during the 37th week of gestation with complaints of rapid weight gain, abdominal disturbance, and pain. Ultrasound examination showed large bilateral ovaries with multiple follicles and mild ascites. At 39 weeks of gestation, the ovaries were the same as detected previously, and a caesarean section was performed due to fetal macrosomia. A healthy female foetus weighing 4060 gr was delivered. The enlarged bilateral ovaries containing multiple follicles were drilled with electrocautery. The ovaries returned to a near normal state for two weeks after the birth. There are no reported cases of spontaneous OHSS in late pregnancy in the literature. Ovarian drilling may be useful during caesarean section. [Cukurova Med J 2015; 40(3.000: 623-626

Primer on spontaneous heating and pyrophoricity

Energy Technology Data Exchange (ETDEWEB)

1994-12-01

This primer was prepared as an information resource for personnel responsible for operation of DOE nuclear facilities. It has sections on combustion principles, spontaneous heating/ignition of hydrocarbons and organics, pyrophoric gases and liquids, pyrophoric nonmetallic solids, pyrophoric metals (including Pu and U), and accident case studies. Although the information in this primer is not all-encompassing, it should provide the reader with a fundamental knowledge level sufficient to recognize most spontaneous combustion hazards and how to prevent ignition and widespread fires. This primer is provided as an information resource only, and is not intended to replace any fire protection or hazardous material training.

Two cases of spontaneous temporal encephalocele.

Science.gov (United States)

Kamiya, Kouhei; Mori, Harushi; Kunimatsu, Akira; Kawai, Kensuke; Usami, Kenichi; Ohtomo, Kuni

2012-12-01

This is a report of two cases of spontaneous temporal encephalocele: one was anteroinferior and presented with epilepsy; the other was posteroinferior and presented with facial neuritis and labyrinthitis. Spontaneous temporal encephalocele is relatively rare and apparently not familiar to a majority of primary physicians. It may present with a variety of symptoms according to its anatomical location, including cerebrospinal fluid fistulas, recurrent meningitis, chronic otitis media, hearing loss, facial nerve palsy and medically intractable epilepsy. Attention should be paid to this disease entity, as it is easily overlooked in imaging studies and can leave serious neurological deficits. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Gauged Supergravities and Spontaneous Supersymmetry Breaking from the Double Copy Construction

Science.gov (United States)

Chiodaroli, M.; Günaydin, M.; Johansson, H.; Roiban, R.

2018-04-01

Supergravities with gauged R symmetry and Minkowski vacua allow for spontaneous supersymmetry breaking and, as such, provide a framework for building supergravity models of phenomenological relevance. In this Letter, we initiate the study of double copy constructions for these supergravities. We argue that, on general grounds, we expect their scattering amplitudes to be described by a double copy of the type (spontaneously broken gauge theory)⊗ (gauge theory with broken supersymmetry). We present a simple realization in which the resulting supergravity has U (1 )R gauge symmetry, spontaneously broken N =2 supersymmetry, and massive gravitini. This is the first instance of a double copy construction of a gauged supergravity and of a theory with spontaneously broken supersymmetry. The construction extends in a straightforward manner to a large family of gauged Yang-Mills-Einstein supergravity theories with or without spontaneous gauge-symmetry breaking.

Spontaneous neutrophil activation in HTLV-1 infected patients

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Jaqueline B. Guerreiro

Full Text Available Human T cell lymphotropic Virus type-1 (HTLV-1 induces lymphocyte activation and proliferation, but little is known about the innate immune response due to HTLV-1 infection. We evaluated the percentage of neutrophils that metabolize Nitroblue tetrazolium (NBT to formazan in HTLV-1 infected subjects and the association between neutrophil activation and IFN-gamma and TNF-alpha levels. Blood was collected from 35 HTLV-1 carriers, from 8 patients with HAM/TSP (HTLV-1- associated myelopathy; 22 healthy individuals were evaluated for spontaneous and lipopolysaccharide (LPS-stimulated neutrophil activity (reduction of NBT to formazan. The production of IFN-gamma and TNF-alpha by unstimulated mononuclear cells was determined by ELISA. Spontaneous NBT levels, as well as spontaneous IFN-gamma and TNF-alpha production, were significantly higher (p<0.001 in HTLV-1 infected subjects than in healthy individuals. A trend towards a positive correlation was noted, with increasing percentage of NBT positive neutrophils and levels of IFN-gamma. The high IFN-gamma producing HTLV-1 patient group had significantly greater NBT than healthy controls, 43±24% and 17±4.8% respectively (p< 0.001, while no significant difference was observed between healthy controls and the low IFN-gamma-producing HTLV-1 patient group (30±20%. Spontaneous neutrophil activation is another marker of immune perturbation resulting from HTLV-1 infection. In vivo activation of neutrophils observed in HTLV-1 infected subjects is likely to be the same process that causes spontaneous IFN-gamma production, or it may partially result from direct IFN-gamma stimulation.

Teaching Spontaneous Responses to Young Children With Autism

OpenAIRE

Jones, Emily A; Feeley, Kathleen M; Takacs, Jennifer

2007-01-01

Using a multiple probe design across responses, we demonstrated the effectiveness of intensive intervention in establishing spontaneous verbal responses to 2 3-year-old children with autism with generalization to novel settings involving novel persons. Intervention involved discrete-trial instruction (i.e., repeated instructional opportunities presented in close proximity to high rates of reinforcement), specific prompts, and error correction. Spontaneous responses were defined as specific ve...

Cytogenetic analysis in 61 couples with spontaneous abortions

Institute of Scientific and Technical Information of China (English)

江静; 傅曼芬; 王德芬

2001-01-01

Objective　To examine the relationship between spontaneous abortion and chromosomal abnormalities. Methods　Couples who had one or more consecutive spontaneous abortions and had normal genitals were enrolled for cytogenetic karyotype analysis. Results　In the 61 couples, the detected incidence was 11.5%, with five Robertsonian translocations, one reciprocal translocation, and one pericentric inversion of chromosome 7. Conclusion　Chromosomal abnormalities may play an important role in fetal wastage.

Spontaneous trait inference and spontaneous trait transference are both unaffected by prior evaluations of informants.

Science.gov (United States)

Zengel, Bettina; Ambler, James K; McCarthy, Randy J; Skowronski, John J

2017-01-01

This article reports results from a study in which participants encountered either (a) previously known informants who were positive (e.g. Abraham Lincoln), neutral (e.g., Jay Leno), or negative (e.g., Adolf Hitler), or (b) previously unknown informants. The informants ostensibly described either a trait-implicative positive behavior, a trait-implicative negative behavior, or a neutral behavior. These descriptions were framed as either the behavior of the informant or the behavior of another person. Results yielded evidence of informant-trait linkages for both self-informants and for informants who described another person. These effects were not moderated by informant type, behavior valence, or the congruency or incongruency between the prior knowledge of the informant and the behavior valence. Results are discussed in terms of theories of Spontaneous Trait Inference and Spontaneous Trait Transference.

Salience of the Nuclear Threat: Operationalization through Spontaneous Concern.

Science.gov (United States)

Mayton, Daniel M., II

An indirect/nonreactive technique of assessing spontaneous concern should be used to examine the salience of the threat of nuclear war. Direct/reactive techniques may produce inconsistent results and inadvertently enhance a false consensus. The procedures for the administration, scoring, and interpretation of a spontaneous concern measure along…

Spontaneous distal rupture of the plantar fascia.

Science.gov (United States)

Gitto, Salvatore; Draghi, Ferdinando

2018-07-01

Spontaneous ruptures of the plantar fascia are uncommon injuries. They typically occur at its calcaneal insertion and usually represent a complication of plantar fasciitis and local treatment with steroid injections. In contrast, distal ruptures commonly result from traumatic injuries. We describe the case of a spontaneous distal rupture of the plantar fascia in a 48-year-old woman with a low level of physical activity and no history of direct injury to the foot, plantar fasciitis, or steroid injections. © 2017 Wiley Periodicals, Inc.

An unusual case of spontaneous esophagopleural fistula

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Manoranjan Dash

2017-01-01

Full Text Available Esophago-pleural fistula (EPF is an uncommon condition, despite of an anatomical proximity of these structures. Causes of EPF include pneumonectomy for suppurative or tubercular disease of lung and carcinoma lung, malignancy of esophagus. Benign EPF is rare and may be due to trauma or infection. The most common infectious cause is tuberculosis. Spontaneous development of fistula between esophagus and pleura is rarely described in literature. We, hereby present a spontaneous case of such a rare entity in a middle-aged male.

Spontaneous regression of retinopathy of prematurity:incidence and predictive factors

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Rui-Hong Ju

2013-08-01

Full Text Available AIM:To evaluate the incidence of spontaneous regression of changes in the retina and vitreous in active stage of retinopathy of prematurity(ROP and identify the possible relative factors during the regression.METHODS: This was a retrospective, hospital-based study. The study consisted of 39 premature infants with mild ROP showed spontaneous regression (Group A and 17 with severe ROP who had been treated before naturally involuting (Group B from August 2008 through May 2011. Data on gender, single or multiple pregnancy, gestational age, birth weight, weight gain from birth to the sixth week of life, use of oxygen in mechanical ventilation, total duration of oxygen inhalation, surfactant given or not, need for and times of blood transfusion, 1,5,10-min Apgar score, presence of bacterial or fungal or combined infection, hyaline membrane disease (HMD, patent ductus arteriosus (PDA, duration of stay in the neonatal intensive care unit (NICU and duration of ROP were recorded.RESULTS: The incidence of spontaneous regression of ROP with stage 1 was 86.7%, and with stage 2, stage 3 was 57.1%, 5.9%, respectively. With changes in zone Ⅲ regression was detected 100%, in zoneⅡ 46.2% and in zoneⅠ 0%. The mean duration of ROP in spontaneous regression group was 5.65±3.14 weeks, lower than that of the treated ROP group (7.34±4.33 weeks, but this difference was not statistically significant (P=0.201. GA, 1min Apgar score, 5min Apgar score, duration of NICU stay, postnatal age of initial screening and oxygen therapy longer than 10 days were significant predictive factors for the spontaneous regression of ROP (P＜0.05. Retinal hemorrhage was the only independent predictive factor the spontaneous regression of ROP (OR 0.030, 95%CI 0.001-0.775, P=0.035.CONCLUSION:This study showed most stage 1 and 2 ROP and changes in zone Ⅲ can spontaneously regression in the end. Retinal hemorrhage is weakly inversely associated with the spontaneous regression.

Predictors of rapid spontaneous resolution of acute subdural hematoma.

Science.gov (United States)

Fujimoto, Kenji; Otsuka, Tadahiro; Yoshizato, Kimio; Kuratsu, Jun-ichi

2014-03-01

Acute subdural hematoma (ASDH) usually requires emergency surgical decompression, but rare cases exhibit rapid spontaneous resolution. The aim of this retrospective study was to identify factors predictive of spontaneous ASDH resolution. A total of 366 consecutive patients with ASDH treated between January 2006 and September 2012 were identified in our hospital database. Patients with ASDH clot thickness >10mm in the frontoparietotemporal region and showing a midline shift >10mm on the initial computed tomography (CT) scan were divided into two groups according to subsequent spontaneous resolution. Univariate and multivariate logistic regression analyses were used to identify factors predictive of rapid spontaneous ASDH resolution. Fifty-six ASDH patients met study criteria and 18 demonstrated rapid spontaneous resolution (32%). Majority of these patients were not operated because of poor prognosis/condition and in accordance to family wishes. Univariate analysis revealed significant differences in use of antiplatelet agents before head injury and in the incidence of a low-density band between the hematoma and inner wall of the skull bone on the initial CT. Use of antiplatelet agents before head injury (OR 19.6, 95% CI 1.5-260.1, p=0.02) and the low-density band on CT images (OR 40.3, 95% CI 3.1-520.2, p=0.005) were identified as independent predictive factors by multivariate analysis. Our analysis suggested that use of antiplatelet agents before head injury and a low-density band between the hematoma and inner skull bone on CT images (indicative of cerebrospinal fluid infusion into the subdural space) increase the probability of rapid spontaneous resolution. Copyright © 2013 Elsevier B.V. All rights reserved.

Spontaneous tension haemopneumothorax

OpenAIRE

Patterson, Benjamin Oliver; Itam, Sarah; Probst, Fey

2008-01-01

Abstract We present a patient with sudden onset progressive shortness of breath and no history of trauma, who rapidly became haemodynamically compromised with a pneumothorax and pleural effusion seen on chest radiograph. He was treated for spontaneous tension pneumothorax but this was soon revealed to be a tension haemopneumothorax. He underwent urgent thoracotomy after persistent bleeding to explore an apical vascular abnormality seen on CT scanning. To our knowledge this is the first such c...

Spontaneous non-thermal leptogenesis in high-scale inflation models

International Nuclear Information System (INIS)

Endo, M.; Takahashi, F.; Yanagida, T.T.; Tokyo Univ.

2006-11-01

We argue that a non-thermal leptogenesis occurs spontaneously, without direct couplings of the inflation with right-handed neutrinos, in a wide class of high-scale inflation models such as the chaotic and hybrid inflation. It is only a finite vacuum expectation value of the inflaton, of more precisely, a linear term in the Kaehler potential, that is a prerequisite for the spontaneous non-thermal leptogenesis. To exemplify how it works, we show that a chaotic inflation model in supergravity naturally produces a right amount of baryon asymmetry via the spontaneous non-thermal leptogenesis. We also discuss the gravitino production from the inflation. (orig.)

Spontaneous fission of 259Md

International Nuclear Information System (INIS)

Hulet, E.K.; Wild, J.F.; Lougheed, R.W.; Baisden, P.A.; Landrum, J.H.; Dougan, R.J.; Mustafa, M.; Ghiorso, A.; Nitschke, J.M.

1979-01-01

The mass and kinetic energy distributions of fission fragments from the spontaneous fission of th newly discovered nuclide 259 Md were obtained. 259 Md was identified as the E. C. daughter of 259 No, and was found to decay entirely (> 95%) by spontaneous fission with a 95-min half-life. From the kinetic energies measured for 397 pairs of coincident fragments, a mass distribution was derived that is symmetric with sigma = 13 amu. 259 Md, together with 258 Fm and 259 Fm, form a select group of three nuclides whose mass division in spontaneous fission is highly symmetric. Unlike the total-kinetic-energy (TKE) distributions of 258 Fm and 259 Fm, which peak at approx. = to 240 MeV, this distribution for 259 Md is broad and is 50 MeV lower in energy. Analysis of the mass and energy distributions shows that events near mass symmetry also exhibit a broad TKE distribution, with one-third of the symmetric events having TKEs less than 200 MeV. The associated of low TKEs with symmetric mass division in the fission of very heavy actinides is anomalous and inconsistent with theories based upon the emergence of fragment shells near the scission point. Either three-body fragmentation or peculiar fragment shapes are assumed as the cause for the large consumption of Coulomb energy observed for a significant fraction of symmetric fissions in 259 Md. 6 figures

Temporal and transverse coherence of self-amplified spontaneous emission

International Nuclear Information System (INIS)

Kim, K.J.

1997-06-01

The authors review the coherence properties of the self-amplified spontaneous emission (SASE). Temporally, SASE is similar to the spontaneous undulator radiation except that the spectral bandwidth is about ten times narrower compared with typical undulator radiation. The situation is quite different in the transverse dimension, where SASE is fully coherent

Surgical management of spontaneous ruptured hepatocellular adenoma

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Marcelo Augusto Fontenelle Ribeiro Junior

2009-01-01

Full Text Available AIMS: Spontaneous ruptured hepatocellular adenoma (SRHA is a rare life-threatening condition that may require surgical treatment to control hemorrhaging and also stabilize the patient. We report a series of emergency surgeries performed at our institution for this condition. METHODS: We reviewed medical records and radiology files of 28 patients (from 1989 to 2006 with a proven diagnosis of hepatocellular adenoma (HA. Three (10.7% of 28 patients had spontaneous ruptured hepatocellular adenoma, two of which were associated with intrahepatic hemorrhage while one had intraperitoneal bleeding. Two patients were female and one was male. Both female patients had a background history of oral contraceptive use. Sudden abdominal pain associated with hemodynamic instability occurred in all patients who suffered from spontaneous ruptured hepatocellular adenoma. The mean age was 41.6 years old. The preoperative assessment included liver function tests, ultrasonography and computed tomography. RESULTS: The surgical approaches were as follows: right hemihepatectomy for controlling intraperitoneal bleeding, and right extended hepatectomy and non-anatomic resection of the liver for intrahepatic hemorrhage. There were no deaths, and the postoperative complications were bile leakage and wound infection (re-operation, as well as intraperitoneal abscess (re-operation and pleural effusion. CONCLUSION: Spontaneous ruptured hepatocellular adenoma may be treated by surgery for controlling hemorrhages and stabilizing the patient, and the decision to operate depends upon both the patient's condition and the expertise of the surgical team.

Spontaneous Communication in Autism Spectrum Disorder: A Review of Topographies and Interventions

Science.gov (United States)

Duffy, Cormac; Healy, Olive

2011-01-01

Lack of spontaneous communicative initiations appears to be a consistent problem in individuals with a diagnosis of autism spectrum disorder (ASD; Fujiki & Brinton, 2009). Spontaneous communication is emitted at a much lower frequency compared to individuals with language impairment and typically developing persons. Deficits of spontaneity in…

Spontaneous Hepatic Rupture Associated with Preeclampsia: Treatment with Hepatic Artery Embolization

Energy Technology Data Exchange (ETDEWEB)

Yang, Seung Boo; Goo, Dong Erk; Chang, Yun Woo; Kim, Yong Jae; Hwang, In Cheol; Han, Hyo Sang; Yoon, Jong Hyun; Lee, Tae Il [Soonchunhyang University Hospital, Gumi (Korea, Republic of)

2010-02-15

Spontaneous rupture of the liver due to preeclampsia is a rare condition of pregnant women, and it can be very dangerous if not treated. We report here on a case of successfully treating spontaneous liver rupture associated with preeclampsia by performing transcatheter hepatic arterial embolization. A 41-year-old woman with spontaneous rupture of the liver associated with preeclampsia was treated by hepatic arterial embolization

Spontaneous Hepatic Rupture Associated with Preeclampsia: Treatment with Hepatic Artery Embolization

International Nuclear Information System (INIS)

Yang, Seung Boo; Goo, Dong Erk; Chang, Yun Woo; Kim, Yong Jae; Hwang, In Cheol; Han, Hyo Sang; Yoon, Jong Hyun; Lee, Tae Il

2010-01-01

Spontaneous rupture of the liver due to preeclampsia is a rare condition of pregnant women, and it can be very dangerous if not treated. We report here on a case of successfully treating spontaneous liver rupture associated with preeclampsia by performing transcatheter hepatic arterial embolization. A 41-year-old woman with spontaneous rupture of the liver associated with preeclampsia was treated by hepatic arterial embolization

Spontaneous lateral sphenoid cerebrospinal fluid fistula: MRI diagnosis

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Matthew Goodier

2012-02-01

Full Text Available Spontaneous or primary cerebrospinal fluid (CSF fistula is a rare cause of CSF rhinorrhoea. Magnetic resonance imaging with high resolution highly T2-weighted images is valuable in preoperative localisation and characterisation of the defect particularly if a transnasal endoscopic approach is planned. This report describes the radiological evaluation and surgical management of a 53 year old male who presented with a spontaneous lateral sphenoid CSF fistula.

Acupuncture and Spontaneous Regression of a Radiculopathic Cervical Herniated Disc

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Kim Sung-Ha

2012-06-01

Full Text Available The spontaneous regression of herniated cervical discs is not a well-established phenomenon. However, we encountered a case of a spontaneous regression of a severe radiculopathic herniated cervical disc that was treated with acupuncture, pharmacopuncture, and herb medicine. The symptoms were improved within 12 months of treatment. Magnetic resonance imaging (MRI conducted at that time revealed marked regression of the herniated disc. This case provides an additional example of spontaneous regression of a herniated cervical disc documented by MRI following non-surgical treatment.

Strong evidence for spontaneous chiral symmetry breaking in (quenched) QCD

International Nuclear Information System (INIS)

Barbour, I.M.; Gibbs, P.; Schierholz, G.; Teper, M.; Gilchrist, J.P.; Schneider, H.

1983-09-01

We calculate the chiral condensate for all quark masses using Kogut-Susskind fermions in lattice-regularized quenched QCD. The large volume behaviour of at small quark masses demonstrates that the explicit U(1) chiral symmetry is spontaneously broken. We perform the calculation for β = 5.1 to 5.9 and find very good continuum renormalization group behaviour. We infer that the spontaneous breaking we observe belongs to continuum QCD. This constitutes the first unambiguous demonstration of spontaneous chiral symmetry breaking in continuum quenched QCD. (orig.)

Need for spontaneous breakdown of chiral symmetry

International Nuclear Information System (INIS)

Salomone, A.; Schechter, J.; Tudron, T.

1981-01-01

The question of whether the chiral symmetry of the theory of strong interactions (with massless quarks) is required to be spontaneously broken is examined in the framework of a previously discussed effective Lagrangian for quantum chromodynamics. The assumption that physical masses of the theory be finite leads in a very direct way to the necessity of spontaneous breakdown. This result holds for all N/sub F/> or =2, where N/sub F/ is the number of different flavors of light quarks. The atypical cases N/sub F/ = 1,2 are discussed separately

Associative memory model with spontaneous neural activity

Science.gov (United States)

Kurikawa, Tomoki; Kaneko, Kunihiko

2012-05-01

We propose a novel associative memory model wherein the neural activity without an input (i.e., spontaneous activity) is modified by an input to generate a target response that is memorized for recall upon the same input. Suitable design of synaptic connections enables the model to memorize input/output (I/O) mappings equaling 70% of the total number of neurons, where the evoked activity distinguishes a target pattern from others. Spontaneous neural activity without an input shows chaotic dynamics but keeps some similarity with evoked activities, as reported in recent experimental studies.

Glycemia in Spontaneous Intracerebral Hemorrhage: Clinical Implications

Directory of Open Access Journals (Sweden)

Alvis-Miranda Hernando

2014-10-01

Full Text Available Spontaneous cerebral hemorrhage or intracranial hemorrhage accounts for 10-15% of all strokes. Intracranial hemorrhage is much less common than ischemic stroke, but has higher mortality and morbidity, one of the leading causes of severe disability. Various alterations, among these the endocrine were identified when an intracerebral hemorrhage, these stress-mediated mechanisms exacerbate secondary injury. Deep knowledge of the injuries which are directly involved alterations of glucose, offers insight as cytotoxicity, neuronal death and metabolic dysregulations alter the prognosis of patients with spontaneous intracerebral hemorrhage.

Spontaneous abortion and physical strain around implantation

DEFF Research Database (Denmark)

Hjøllund, Niels Henrik Ingvar; Jensen, T.K.; Bonde, J.P.

2000-01-01

Existing studies of physical strain and spontaneous abortion are mainly retrospective or based only on pregnancies that have survived the first trimester. Furthermore, almost all studies have relied on averaged measures of physical strain, which tend to blur an effect if peak values during short...... pregnancy the women recorded physical strain prospectively in a structured diary. Physical strain around the time of implantation was associated with later spontaneous abortion. The adjusted risk ratio for women who reported physical strain higher than average at day 6 to 9 after the estimated date...

Spontaneous Play and Imagination in Everyday Science Classroom Practice

Science.gov (United States)

Andrée, Maria; Lager-Nyqvist, Lotta

2013-01-01

In science education, students sometimes create and engage in spontaneous science-oriented play where ideas about science and scientists are put to use. However, in previous research, little attention has been given to the role of informal spontaneous play in school science classrooms. We argue that, in order to enhance our understanding of…

G protein betagamma-subunits activated by serotonin mediate presynaptic inhibition by regulating vesicle fusion properties.

Science.gov (United States)

Photowala, Huzefa; Blackmer, Trillium; Schwartz, Eric; Hamm, Heidi E; Alford, Simon

2006-03-14

Neurotransmitters are thought to be released as quanta, where synaptic vesicles deliver packets of neurotransmitter to the synaptic cleft by fusion with the plasma membrane. However, synaptic vesicles may undergo incomplete fusion. We provide evidence that G protein-coupled receptors inhibit release by causing such incomplete fusion. 5-hydroxytryptamine (5-HT) receptor signaling potently inhibits excitatory postsynaptic currents (EPSCs) between lamprey reticulospinal axons and their postsynaptic targets by a direct action on the vesicle fusion machinery. We show that 5-HT receptor-mediated presynaptic inhibition, at this synapse, involves a reduction in EPSC quantal size. Quantal size was measured directly by comparing unitary quantal amplitudes of paired EPSCs before and during 5-HT application and indirectly by determining the effect of 5-HT on the relationship between mean-evoked EPSC amplitude and variance. Results from FM dye-labeling experiments indicate that 5-HT prevents full fusion of vesicles. 5-HT reduces FM1-43 staining of vesicles with a similar efficacy to its effect on the EPSC. However, destaining of FM1-43-labeled vesicles is abolished by lower concentrations of 5-HT that leave a substantial EPSC. The use of a water-soluble membrane impermeant quenching agent in the extracellular space reduced FM1-43 fluorescence during stimulation in 5-HT. Thus vesicles contact the extracellular space during inhibition of synaptic transmission by 5-HT. We conclude that 5-HT, via free Gbetagamma, prevents the collapse of synaptic vesicles into the presynaptic membrane.

Learning shapes spontaneous activity itinerating over memorized states.

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Tomoki Kurikawa

Full Text Available Learning is a process that helps create neural dynamical systems so that an appropriate output pattern is generated for a given input. Often, such a memory is considered to be included in one of the attractors in neural dynamical systems, depending on the initial neural state specified by an input. Neither neural activities observed in the absence of inputs nor changes caused in the neural activity when an input is provided were studied extensively in the past. However, recent experimental studies have reported existence of structured spontaneous neural activity and its changes when an input is provided. With this background, we propose that memory recall occurs when the spontaneous neural activity changes to an appropriate output activity upon the application of an input, and this phenomenon is known as bifurcation in the dynamical systems theory. We introduce a reinforcement-learning-based layered neural network model with two synaptic time scales; in this network, I/O relations are successively memorized when the difference between the time scales is appropriate. After the learning process is complete, the neural dynamics are shaped so that it changes appropriately with each input. As the number of memorized patterns is increased, the generated spontaneous neural activity after learning shows itineration over the previously learned output patterns. This theoretical finding also shows remarkable agreement with recent experimental reports, where spontaneous neural activity in the visual cortex without stimuli itinerate over evoked patterns by previously applied signals. Our results suggest that itinerant spontaneous activity can be a natural outcome of successive learning of several patterns, and it facilitates bifurcation of the network when an input is provided.

General theory of spontaneous emission near exceptional points.

Science.gov (United States)

Pick, Adi; Zhen, Bo; Miller, Owen D; Hsu, Chia W; Hernandez, Felipe; Rodriguez, Alejandro W; Soljačić, Marin; Johnson, Steven G

2017-05-29

We present a general theory of spontaneous emission at exceptional points (EPs)-exotic degeneracies in non-Hermitian systems. Our theory extends beyond spontaneous emission to any light-matter interaction described by the local density of states (e.g., absorption, thermal emission, and nonlinear frequency conversion). Whereas traditional spontaneous-emission theories imply infinite enhancement factors at EPs, we derive finite bounds on the enhancement, proving maximum enhancement of 4 in passive systems with second-order EPs and significantly larger enhancements (exceeding 400×) in gain-aided and higher-order EP systems. In contrast to non-degenerate resonances, which are typically associated with Lorentzian emission curves in systems with low losses, EPs are associated with non-Lorentzian lineshapes, leading to enhancements that scale nonlinearly with the resonance quality factor. Our theory can be applied to dispersive media, with proper normalization of the resonant modes.

The spontaneous market order and evolution.

Science.gov (United States)

Beck, Naomi

2016-08-01

Darwin's theory of natural selection and the idea of a spontaneous order share a fundamental feature: the claim that apparent design or order do not necessarily imply a designer or rational planning. But they also present important differences, which touch upon central questions such as the evolution of morality, the role of human agency in social evolution, the existence (or not) of directionality in undesigned processes, and the presence (nor not) of a providential element in evolutionary accounts. In this article, I explore these themes and probe the relationship between the notion of a spontaneous order and the theory of evolution by natural selection. The reflections of Nobel laureate in economics, F.A. von Hayek, provide the beginning and endpoint in this voyage, for they constitute the most pronounced effort to develop a full-fledged theory combining evolution and economics in recent times. But along the way, I also investigate the influence of classical political economy on Darwin's thought, primarily that of Adam Smith, and consider the reasons for which Darwin did not refer to Smith when discussing the principle of natural selection in The Origin of Species. I conclude that the spontaneous order, as understood by Hayek, and evolution by natural selection constitute two disparate concepts. Copyright © 2015 Elsevier Ltd. All rights reserved.

Factors affecting the spontaneous mutational spectra in somatic mammalian cells

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О.А. Ковальова

2006-04-01

Full Text Available  In our survey of references we are discussed the influence of factors biological origin on the spontaneous mutation specters in mammalian. Seasonal and age components influence on the frequence of cytogenetic anomalies. The immune and endocrinous systems are take part in control of the alteration of the spontaneous mutation specters. Genetical difference of sensibility in animal and human at the alteration of factors enviroment as and  genetical differences of repair systems activity are may influence on individual variation of spontaneous destabilization characters of chromosomal apparatus.

Four cases of spontaneous rupture of the urinary bladder

International Nuclear Information System (INIS)

Amano, Toshiyasu; Miwa, Sotaro; Takashima, Hiroshi; Takemae, Katsuro

2002-01-01

Between November 1997 and March 2001, 4 female patients from 44 to 65 years of age with a spontaneous rupture of the urinary bladder were analyzed. They complained of abdominal pain and had undergone an intra-pelvic gynecological operation (3 for uterine cancer, 1 for an ovarian cyst) several years before. The three with uterine cancer had also received radiation therapy. For their present condition, spontaneous urinary bladder rupture, their treatment was indwelling a urethral catheter. Two of them have had no recurrence of urinary bladder rupture after one month since having the urethral catheter indwelt. One, however, had to have the catheter re-indwelt due to unsuccessful suturing of the urinary bladder wall. The fourth patient had bilateral nephrostomy tubes due to severe radiation cystitis. Thus, one can infer that intra-pelvic gynecological operations and radiation therapy are major factors causing spontaneous urinary bladder rupture. While indwelling a urethral catheter may be effective for some patients with a spontaneous rupture of the urinary bladder, it may be very difficult to treat more complicated cases. (author)

Increased spontaneous mitotic segregation in MMS-sensitive mutants of Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Prakash, S.; Prakash, L.

1977-01-01

Methyl methanesulfonate (MMS)-sensitive mutants of Saccharomyces cerevisiae belonging to four different complementation groups, when homozygous, increase the rate of spontaneous mitotic segregation to canavanine resistance from heterozygous sensitive (can/sup r//+) diploids by 13- to 170-fold. The mms8-1 mutant is MMS and x-ray sensitive and increases the rate of spontaneous mitotic segregation 170-fold. The mms9-1 and mms13-1 mutants are sensitive to x rays and uv, respectively, in addition to MMS, and increase the rate of spontaneous mitotic segregation by 13-fold and 85-fold, respectively. The mutant mms21-1 is sensitive to MMS, x rays and uv and increases the rate of spontaneous mitotic segregation 23-fold

Spontaneously emerging cortical representations of visual attributes

Science.gov (United States)

Kenet, Tal; Bibitchkov, Dmitri; Tsodyks, Misha; Grinvald, Amiram; Arieli, Amos

2003-10-01

Spontaneous cortical activity-ongoing activity in the absence of intentional sensory input-has been studied extensively, using methods ranging from EEG (electroencephalography), through voltage sensitive dye imaging, down to recordings from single neurons. Ongoing cortical activity has been shown to play a critical role in development, and must also be essential for processing sensory perception, because it modulates stimulus-evoked activity, and is correlated with behaviour. Yet its role in the processing of external information and its relationship to internal representations of sensory attributes remains unknown. Using voltage sensitive dye imaging, we previously established a close link between ongoing activity in the visual cortex of anaesthetized cats and the spontaneous firing of a single neuron. Here we report that such activity encompasses a set of dynamically switching cortical states, many of which correspond closely to orientation maps. When such an orientation state emerged spontaneously, it spanned several hypercolumns and was often followed by a state corresponding to a proximal orientation. We suggest that dynamically switching cortical states could represent the brain's internal context, and therefore reflect or influence memory, perception and behaviour.

Case of a spontaneously ruptured epidermoid cyst

Energy Technology Data Exchange (ETDEWEB)

Shiroyama, Y; Saiki, M; Ueda, H; Katayama, S; Mitani, T

1987-02-01

Intracranial fat-containing congenital tumors are characterized by negative absorption values on CT. We hereby report a case of an epidermoid cyst with subarachnoid free fats diagnosed preoperatively by CT. A 21-year-old female was admitted to our hospital because of continuous mild headache and nausea. At the time of admission, the results of her physical and neurological examinations were normal. CT, however, demonstrated multiple subarachnoid low-density spots and a suprasellar low-density area with high-density spots. In addition, there were negative absorption values (-12 -- -77), suggesting free fats. A spontaneously ruptured epidermoid or dermoid cyst was diagnosed on the basis of these findings. At surgery, a suprasellar tumor containing a yellowish, cheese-like material was confirmed. The patient made an uneventful recovery and was discharged 14 days after surgery. There have been several published reports of CT appearances of intracranial fat-containing tumors. However, spontaneously ruptured cases diagnosed by CT are rare. CT was found to be useful for the diagnosis of spontaneously ruptured cases of fat-containing tumors.

The Spontaneous Combustion of Railway Ties and Asphalt Shingles

Science.gov (United States)

Leslie, Geoffrey

Many Low Carbon Fuels (LCFs) present unknown spontaneous combustion risks, which must be quantified before their use as fossil fuel replacements. Wood and coal spontaneous combustion is well understood; however, LCFs weather, and subsequent chemical changes could affect their spontaneous combustion properties. LCF spontaneous combustion could lead to accidental fires with possible loss of life, limb and property. The spontaneous combustion risks of two LCFs, discarded creosote-treated wooden railway ties and roofing asphalt shingles, were investigated with calorimetry and heat transfer experiments. Chemical changes due to weathering were studied with pyrolysis-Gas Chromatography/Mass Spectrometry (py-GC/MS). Creosote-treated wooden railway tie dust, roofing asphalt shingle particles, poplar wood pellets, and petroleum coke self-heating were studied with isothermal calorimetry. Railway tie dust and asphalt shingle heat transfer were characterized with a guarded hot plate. Petroleum coke self-heating was consistent with coal, while both poplar pellets and railway tie dust were found to be more reactive compared to oven test results of similar materials. The observed increase in reactivity was probably a result of significant moisture contenint in the pellet and railway tie dust. Critical conditions for spontaneous combustion were evaluated with the Frank-Kamenetskii parameter, assuming an ambient temperature of 40°C and constant moisture content. Kamenetskii calculations indicate that a 1.6 m cube of railway tie dust, or a 58 m cube of asphalt particles, would be unstable and combust. LCF chemistry may have been affected by weathering, which would cause chemical changes that affect their spontaneous combustion properties. Therefore, railway tie wood and roofing asphalt shingle chemistry were investigated by identifying products of 250° and 550°C pyrolysis with py-GC/MS. Railway tie wood pyrolyzates did not show signs of weathering; in contrast, asphalt pyrolysis

Spontaneous fungal peritonitis: a rare but severe complication of liver cirrhosis.

Science.gov (United States)

Gravito-Soares, Marta; Gravito-Soares, Elisa; Lopes, Sandra; Ribeiro, Graça; Figueiredo, Pedro

2017-09-01

Spontaneous bacterial peritonitis is the most common infectious complication in cirrhosis. Spontaneous fungal peritonitis is rare and remains unknown. In this work, spontaneous fungal peritonitis as well as risk factors and prognosis are characterized. A retrospective case-control study of 253 consecutive admissions by peritonitis in cirrhotic patients was carried out between 2006 and 2015. Comparison of patients with spontaneous fungal peritonitis (cases) and spontaneous bacterial peritonitis with positive microbiologic ascitic fluid culture (controls) was performed. Variables such as sociodemographic and clinical features, cirrhosis etiology, liver dysfunction scores, ascitic and laboratory parameters, invasive procedures, and prognosis were evaluated. Of the 231 patients, eight (3.5%) developed spontaneous fungal peritonitis, 62.5% of cases being coinfected with bacteria. Candida spp. was isolated in 87.5% of cases, mainly Candida albicans (37.5%) and C. krusei (25.0%). Patients with spontaneous fungal peritonitis had higher ascitic fluid lactate dehydrogenase (288.4±266.6 vs. 161.0±179.5; P=0.011), blood leukocyte count (15187.5±5432.3 vs. 10969.8±6949.5; P=0.028), blood urea nitrogen (69.8±3.1 vs. 36.3±25.5; P=0.001), higher number of invasive procedures (colonoscopy: 25.0 vs. 0.8%, P=0.001; urinary catheterization: 87.5 vs. 49.6%, P=0.038; nasogastric intubation: 87.5 vs. 26.9%, P=0.001), and longer duration of hospital stay (30.0±32.9 vs. 18.9±17.0 days; P=0.031). No statistical difference was found between the two groups for Model for End-Stage Liver Disease, Model for End-Stage Liver Disease-sodium, and Child-Pugh scores. Spontaneous fungal peritonitis was associated with a worse prognosis, particularly severe sepsis/septic shock (87.5 vs. 42.8%, P=0.023), admission in the gastroenterology intensive care unit (87.5 vs. 24.4%; P=0.001), and overall (62.5 vs. 31.9%; P=0.039) or 30-day mortality (50.0 vs. 24.4%; P=0.034), with a mean diagnosis

Spontaneous ejaculation in a wild Indo-Pacific bottlenose dolphin (Tursiops aduncus.

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Tadamichi Morisaka

Full Text Available Spontaneous ejaculation, which is defined as the release of seminal fluids without apparent sexual stimulation, has been documented in boreoeutherian mammals. Here we report spontaneous ejaculation in a wild Indo-Pacific bottlenose dolphin (Tursiops aduncus, and present a video of this rare behavior. This is the first report of spontaneous ejaculation by an aquatic mammal, and the first video of this behavior in animals to be published in a scientific journal.

The importance of causal connections in the comprehension of spontaneous spoken discourse.

Science.gov (United States)

Cevasco, Jazmin; van den Broek, Paul

2008-11-01

In this study, we investigated the psychological processes in spontaneous discourse comprehension through a network theory of discourse representation. Existing models of narrative comprehension describe the importance of causality processing for forming a representation of a text, but usually in the context of deliberately composed texts rather than in spontaneous, unplanned discourse. Our aim was to determine whether spontaneous discourse components with many causal connections are represented more strongly than components with few connections--similar to the findings in text comprehension literature--and whether any such effects depend on the medium in which the spontaneous discourse is presented (oral vs. written). Participants either listened to or read a transcription of a section of a radio transmission. They then recalled the spontaneous discourse material and answered comprehension questions. Results indicate that the processing of causal connections plays an important role in the comprehension of spontaneous spoken discourse, and do not indicate that their effects on recall are weaker in the comprehension of oral discourse than in the comprehension of written discourse.

Male-mediated spontaneous abortion among spouses of stainless steel welders

DEFF Research Database (Denmark)

Hjollund, N H; Bonde, J P; Jensen, T K

2000-01-01

Male-mediated spontaneous abortion has never been documented for humans. The welding of stainless steel is associated with the pulmonary absorption of hexavalent chromium, which has genotoxic effects on germ cells in rodents. Clinical and early subclinical spontaneous abortions were examined among...

Spontaneous esophageal-pleural fistula

OpenAIRE

Vyas, Sameer; Prakash, Mahesh; Kaman, Lileshwar; Bhardwaj, Nidhi; Khandelwal, Niranjan

2011-01-01

Spontaneous esophageal-pleural fistula (EPF) is a rare entity. We describe a case in a middle-aged female who presented with severe retrosternal chest pain and shortness of breadth. Chest computed tomography showed right EPF and hydropneumothorax. She was managed conservatively keeping the chest tube drainage and performing feeding jejunostomy. A brief review of the imaging finding and management of EPF is discussed.

Spontaneous esophageal-pleural fistula.

Science.gov (United States)

Vyas, Sameer; Prakash, Mahesh; Kaman, Lileshwar; Bhardwaj, Nidhi; Khandelwal, Niranjan

2011-10-01

Spontaneous esophageal-pleural fistula (EPF) is a rare entity. We describe a case in a middle-aged female who presented with severe retrosternal chest pain and shortness of breadth. Chest computed tomography showed right EPF and hydropneumothorax. She was managed conservatively keeping the chest tube drainage and performing feeding jejunostomy. A brief review of the imaging finding and management of EPF is discussed.

Spontaneous Bilateral Meningoencephalocoeles of the Temporal Bones

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Oliver Rose

2013-01-01

Full Text Available Spontaneous tegmen tympani defects are rare with even rarer bilateral cases. The symptoms are nonspecific; hence, a high index of suspicion is required to prevent serious intracranial complications. We present a case of spontaneous bilateral tegmen tympani defects with associated meningoencephalocoeles in a 54-year-old male who presented with the signs and symptoms of severe meningitis. After careful workup which included a lumbar puncture, CT and MRI scans, both defects were repaired using a middle fossa approach. The patient made an uneventful recovery with complete cessation of otorrhoea and improvement in his hearing.

[Atypical etiology of rhinorrhea: spontaneous bilateral temporal encephalocele].

Science.gov (United States)

Lorente Muñoz, Asís; Lisbona Alquézar, María Pilar; González Martínez, Luis; Sevil Navarro, Jorge; Llorente Arenas, Eva María

2012-01-01

Spontaneous herniation of brain parenchyma through a dural and osseous defect in the temporal bone is a rare entity and a bilateral form is even more infrequent. It usually presents as an intermittent but persistent otorrhea. Manifestation as nose cerebrospinal fluid (CSF) leak is very uncommon. Our objective is presenting this unusual case report of a spontaneous bilateral encephalocele with a bilateral tegmen tympani defect. Copyright © 2010 Elsevier España, S.L. All rights reserved.

Shell theorem for spontaneous emission

DEFF Research Database (Denmark)

Kristensen, Philip Trøst; Mortensen, Jakob Egeberg; Lodahl, Peter

2013-01-01

and therefore is given exactly by the dipole approximation theory. This surprising result is a spontaneous emission counterpart to the shell theorems of classical mechanics and electrostatics and provides insights into the physics of mesoscopic emitters as well as great simplifications in practical calculations....

Spontaneous regression of metastases from malignant melanoma: a case report

DEFF Research Database (Denmark)

Kalialis, Louise V; Drzewiecki, Krzysztof T; Mohammadi, Mahin

2008-01-01

A case of a 61-year-old male with widespread metastatic melanoma is presented 5 years after complete spontaneous cure. Spontaneous regression occurred in cutaneous, pulmonary, hepatic and cerebral metastases. A review of the literature reveals seven cases of regression of cerebral metastases; thi...

Teaching spontaneous responses to a young child with Down syndrome.

Science.gov (United States)

Feeley, Kathleen; Jones, Emily

2008-10-01

Children with Down syndrome experience significant communication impairments, particularly in expressive language. Although receiving little attention in the literature, deficiencies in expressive language are likely to affect spontaneous communicative responses in children with Down syndrome. In this study, using a multiple baseline design across responses, we demonstrated the effectiveness of discrete trial instruction in establishing spontaneous responses in a preschooler with Down syndrome. Spontaneous responses generalised to a novel setting involving a novel person and novel materials. Implications for the use of behaviourally based interventions to address the social-communicative needs of children with Down syndrome are discussed.

Spontaneous breaking of the BRST symmetry in the ABJM theory

International Nuclear Information System (INIS)

Faizal, Mir; Upadhyay, Sudhaker

2014-01-01

In this paper, we will analyze the ghost condensation in the ABJM theory. We will perform our analysis in N=1 superspace. We show that in the Delbourgo–Jarvis–Baulieu–Thierry–Mieg gauge the spontaneous breaking of BRST symmetry can occur in the ABJM theory. This spontaneous breaking of BRST symmetry is caused by ghost–anti-ghost condensation. We will also show that in the ABJM theory, the ghost–anti-ghost condensates remain present in the modified abelian gauge. Thus, the spontaneous breaking of BRST symmetry in ABJM theory can even occur in the modified abelian gauge

Male Factors and socioeconomic indicators correlate with the risk of spontaneous abortion

DEFF Research Database (Denmark)

Olsen, Jørn; Basso, Olga; Christensen, Kaare

1999-01-01

and environmental factors by studying reproductive histories in population based cohorts. We based the study upon two cohorts. The 'abortion cohort' consisted of 55 259 women who had a hospitalised spontaneous abortion in Denmark between 1980 and 1992 and who had a subsequent non-terminated pregnancy. The 'birth...... the municipality of residence to a low risk area (based upon the geographical distribution of spontaneous abortions) reduced the risk of spontaneous abortion in both cohorts. A paternal effect on the recurrence risk of spontaneous abortion cannot be ruled out but environmental factors also play a role.......No less than 10% of clinically recognised pregnancies end as spontaneous abortions and the recurrence risk is high. Due to lack of data and appropriate study design only little is known about preventable causes of miscarriage. The aim of this study was to estimate the effect of paternal...

Computed tomography characteristics suggestive of spontaneous resolution of chronic subdural hematoma

Energy Technology Data Exchange (ETDEWEB)

Horikoshi, Toru; Naganuma, Hirofumi; Fukasawa, Isao; Uchida, Mikito; Nukui, Hideaki [Yamanashi Medical Univ., Tamaho (Japan)

1998-09-01

The clinical and radiological characteristics of self-resolving hematoma were assessed retrospectively in a series of patients with chronic subdural hematomas (SDHs) treated over a recent 6-year period in a local hospital. Spontaneous resolution was observed in five of 27 hematomas occurring in four of 23 patients. Clinical and radiological findings of the four cases were compared to those of the remaining 19 cases. All spontaneously resolving SDHs were asymptomatic or only caused mild transient headache, and disappeared within 4 to 9 months after head injury. All spontaneously resolving SDHs were located in the frontal region, and maximum thickness and midline displacement were less than those in the other 19 patients who were symptomatic and underwent surgery. Computed tomography demonstrated a low density line between the hematoma and the cerebral cortex, indicative of remaining cerebrospinal fluid space in four of five hematomas. Spontaneously resolving SDH is more frequent than formerly expected. Asymptomatic SDHs localized in the frontal region with small mass signs can be expected to disappear spontaneously without deterioration. (author)

Spontaneous neonatal gastrointestinal perforation: surgical or ...

African Journals Online (AJOL)

... cases of spontaneous gastrointestinal perforation in neonates at the University of Benin Teaching Hospital, Benin City. The perinatal stress factors were caesarian delivery, prematurity and fetal distress due to prolonged obstructed labour.

Silicosis with bilateral spontaneous pneumothorax

Directory of Open Access Journals (Sweden)

Fotedar Sanjay

2010-01-01

Full Text Available Presentation with simultaneous bilateral pneumothorax is uncommon and usually in the context of secondary spontaneous pneumothorax.The association of pneumothorax and silicosis is infrequent and most cases are unilateral. Bilateral pneumothorax in silicosis is very rare with just a few reports in medical literature.

Spontaneous decoherence of coupled harmonic oscillators confined in a ring

Science.gov (United States)

Gong, ZhiRui; Zhang, ZhenWei; Xu, DaZhi; Zhao, Nan; Sun, ChangPu

2018-04-01

We study the spontaneous decoherence of coupled harmonic oscillators confined in a ring container, where the nearest-neighbor harmonic potentials are taken into consideration. Without any external symmetry-breaking field or surrounding environment, the quantum superposition state prepared in the relative degrees of freedom gradually loses its quantum coherence spontaneously. This spontaneous decoherence is interpreted by the gauge couplings between the center-of-mass and the relative degrees of freedoms, which actually originate from the symmetries of the ring geometry and the corresponding nontrivial boundary conditions. In particular, such spontaneous decoherence does not occur at all at the thermodynamic limit because the nontrivial boundary conditions become the trivial Born-von Karman boundary conditions when the perimeter of the ring container tends to infinity. Our investigation shows that a thermal macroscopic object with certain symmetries has a chance for its quantum properties to degrade even without applying an external symmetry-breaking field or surrounding environment.

Differentiating the Causes of Spontaneous Rib Fracture After Breast Cancer.

Science.gov (United States)

Harris, Susan R

2016-12-01

Spontaneous rib fracture after treatment for primary breast cancer is not uncommon. Although metastatic disease accounts for about 30% of spontaneous rib fractures and should constitute the first line of diagnostic investigation, other possible contributors include primary osteoporosis or secondary osteoporosis resulting from cancer treatments. Chemotherapy-induced menopause, aromatase inhibitors, radiation therapy, and long-term bisphosphonate use can all contribute to bone fragility, including spontaneous rib fractures in the latter 3. Drawing on recent breast cancer practice guidelines as well as population-based studies of fracture risk for women with a history of breast cancer and systematic reviews, this Perspective will provide an update on recent developments in understanding how to differentiate the possible reasons for non-traumatic rib fracture in women treated for breast cancer. In addition to describing the various possible causes of spontaneous rib fracture, the recommended medical and imaging procedures for differentiating among the potential causes will be presented. Copyright © 2016 Elsevier Inc. All rights reserved.

Observation of Spontaneous Expressive Language (OSEL): A New Measure for Spontaneous and Expressive Language of Children with Autism Spectrum Disorders and Other Communication Disorders

Science.gov (United States)

Kim, So Hyun; Junker, Dörte; Lord, Catherine

2014-01-01

A new language measure, the Observation of Spontaneous Expressive Language (OSEL), is intended to document spontaneous use of syntax, pragmatics, and semantics in 2-12-year-old children with Autism Spectrum Disorder (ASD) and other communication disorders with expressive language levels comparable to typical 2-5 year olds. Because the purpose of…

Management of intractable spontaneous epistaxis

Science.gov (United States)

Rudmik, Luke

2012-01-01

Background: Epistaxis is a common otolaryngology emergency and is often controlled with first-line interventions such as cautery, hemostatic agents, or anterior nasal packing. A subset of patients will continue to bleed and require more aggressive therapy. Methods: Intractable spontaneous epistaxis was traditionally managed with posterior nasal packing and prolonged hospital admission. In an effort to reduce patient morbidity and shorten hospital stay, surgical and endovascular techniques have gained popularity. A literature review was conducted. Results: Transnasal endoscopic sphenopalatine artery ligation and arterial embolization provide excellent control rates but the decision to choose one over the other can be challenging. The role of transnasal endoscopic anterior ethmoid artery ligation is unclear but may be considered in certain cases when bleeding localizes to the ethmoid region. Conclusion: This article will focus on the management of intractable spontaneous epistaxis and discuss the role of endoscopic arterial ligation and embolization as it pertains to this challenging clinical scenario. PMID:22391084

Spontaneous symmetry breaking and response functions

International Nuclear Information System (INIS)

Beraudo, A.; De Pace, A.; Martini, M.; Molinari, A.

2005-01-01

We study the quantum phase transition occurring in an infinite homogeneous system of spin 1/2 fermions in a non-relativistic context. As an example we consider neutrons interacting through a simple spin-spin Heisenberg force. The two critical values of the coupling strength-signaling the onset into the system of a finite magnetization and of the total magnetization, respectively-are found and their dependence upon the range of the interaction is explored. The spin response function of the system in the region where the spin-rotational symmetry is spontaneously broken is also studied. For a ferromagnetic interaction the spin response along the direction of the spontaneous magnetization occurs in the particle-hole continuum and displays, for not too large momentum transfers, two distinct peaks. The response along the direction orthogonal to the spontaneous magnetization displays instead, beyond a softened and depleted particle-hole continuum, a collective mode to be identified with a Goldstone boson of type II. Notably, the random phase approximation on a Hartree-Fock basis accounts for it, in particular for its quadratic-close to the origin-dispersion relation. It is shown that the Goldstone boson contributes to the saturation of the energy-weighted sum rule for ∼25% when the system becomes fully magnetized (that is in correspondence of the upper critical value of the interaction strength) and continues to grow as the interaction strength increases

Uncovering intrinsic modular organization of spontaneous brain activity in humans.

Directory of Open Access Journals (Sweden)

Yong He

Full Text Available The characterization of topological architecture of complex brain networks is one of the most challenging issues in neuroscience. Slow (<0.1 Hz, spontaneous fluctuations of the blood oxygen level dependent (BOLD signal in functional magnetic resonance imaging are thought to be potentially important for the reflection of spontaneous neuronal activity. Many studies have shown that these fluctuations are highly coherent within anatomically or functionally linked areas of the brain. However, the underlying topological mechanisms responsible for these coherent intrinsic or spontaneous fluctuations are still poorly understood. Here, we apply modern network analysis techniques to investigate how spontaneous neuronal activities in the human brain derived from the resting-state BOLD signals are topologically organized at both the temporal and spatial scales. We first show that the spontaneous brain functional networks have an intrinsically cohesive modular structure in which the connections between regions are much denser within modules than between them. These identified modules are found to be closely associated with several well known functionally interconnected subsystems such as the somatosensory/motor, auditory, attention, visual, subcortical, and the "default" system. Specifically, we demonstrate that the module-specific topological features can not be captured by means of computing the corresponding global network parameters, suggesting a unique organization within each module. Finally, we identify several pivotal network connectors and paths (predominantly associated with the association and limbic/paralimbic cortex regions that are vital for the global coordination of information flow over the whole network, and we find that their lesions (deletions critically affect the stability and robustness of the brain functional system. Together, our results demonstrate the highly organized modular architecture and associated topological properties in

Orofacial neuropathic pain reduces spontaneous burrowing behavior in rats.

Science.gov (United States)

Deseure, K; Hans, G

2018-07-01

It was recently reported that spontaneous burrowing behavior is decreased after tibial nerve transection, spinal nerve transection and partial sciatic nerve ligation. It was proposed that spontaneous burrowing could be used as a measure of the impact of neuropathic pain after peripheral nerve injury. It has remained unclear whether the reduction in burrowing behavior is caused directly by pain or hypersensitivity in the affected limbs, making it more difficult to perform burrowing, or by a pain induced decrease in the general wellbeing, thus reducing the motivation to burrow. We studied burrowing behavior after infraorbital nerve injury, a model of orofacial neuropathic pain that does not affect the limbs. Burrowing behavior was significantly reduced after infraorbital nerve injury. Isolated face grooming and responsiveness to mechanical von Frey stimulation of the infraorbital nerve territory were significantly increased after infraorbital nerve injury, indicative, respectively, of spontaneous pain and mechanical allodynia. It is concluded that spontaneous burrowing may provide a measure of the global impact of pain on the animal's wellbeing after peripheral nerve injury and incorporation of this behavioral assay in preclinical drug testing may improve the predictive validity of currently used pain models. Copyright © 2018 Elsevier Inc. All rights reserved.

A Spontaneous Ad Hoc Network to Share WWW Access

Directory of Open Access Journals (Sweden)

Lloret Jaime

2010-01-01

Full Text Available In this paper, we propose a secure spontaneous ad-hoc network, based on direct peer-to-peer interaction, to grant a quick, easy, and secure access to the users to surf the Web. The paper shows the description of our proposal, the procedure of the nodes involved in the system, the security algorithms implemented, and the designed messages. We have taken into account the security and its performance. Although some people have defined and described the main features of spontaneous ad-hoc networks, nobody has published any design and simulation until today. Spontaneous networking will enable a more natural form of wireless computing when people physically meet in the real world. We also validate the success of our proposal through several simulations and comparisons with a regular architecture, taking into account the optimization of the resources of the devices. Finally, we compare our proposal with other caching techniques published in the related literature. The proposal has been developed with the main objective of improving the communication and integration between different study centers of low-resource communities. That is, it lets communicate spontaneous networks, which are working collaboratively and which have been created on different physical places.

Spontaneous esophageal-pleural fistula

Directory of Open Access Journals (Sweden)

Sameer Vyas

2011-01-01

Full Text Available Spontaneous esophageal-pleural fistula (EPF is a rare entity. We describe a case in a middle-aged female who presented with severe retrosternal chest pain and shortness of breadth. Chest computed tomography showed right EPF and hydropneumothorax. She was managed conservatively keeping the chest tube drainage and performing feeding jejunostomy. A brief review of the imaging finding and management of EPF is discussed.

Radionuclide cisternographic findings in patients with spontaneous intracranial hypotension

International Nuclear Information System (INIS)

Jung, Dong Jin; Kim, Jae Seung; Ryu, Jin Sook; Shin, Jung Woo; Im, Joo Hyuk; Lee, Myoung Chong; Jung, Sung Joo; Moon, Dae Hyuk; Lee, Hee Kyung

1998-01-01

Radionuclide cisternography may be helpful in understanding pathophysiology of postural headache and low CSF pressure in patients with spontaneous intracranial hypotension. The purpose of this study was to characterize radionuclide cisternogrpahic findings of spontaneous intracranial hypotension. The study population consists of 15 patients with spontaneous intracranial hypotension. Diagnosis was based on their clinical symptoms and results of lumbar puncture. All patients underwent radionuclide cisternography following injection of 111 to 222 MBq of Tc-99m DTPA into the lumbar subarachnoid space. Sequential images were obtained between 1/2 hour and 24 hour after the injection of Tc-99m DTPA. Radioactivity of the bladder, soft tissue uptake, migration of radionuclide in the subarachnoid space, and extradural leakage of radionuclide were evaluated according to the scan time. Radionuclide cisternogram showed delayed migration of radionuclide into the cerebral convexity (14/15), increased soft tissue uptake (11/15), and early visualization of bladder activity at 30 min (6/10) and 2 hr (13/13). Cisternography also demonstrated leakage site of CSF in 4 cases and 2 of these were depicted at 30min. Epidural blood patch was done in 11 patients and headache was improved in all cases. The characteristics findings of spontaneous intracranial hypotension were delayed migration of radionuclide and early visualization of the soft tissue and bladder activity. These scintigraphic findings suggest that CSF leakage rather than increased CSF absorption or decreased production may be the main pathophysiology of spontaneous intracranial hypotension. Early and multiple imaging including the bladder and soft tissue is required to observe the entire dynamics of radionuclide migration

[Treatment of the first episode of spontaneous pneumothorax].

Science.gov (United States)

Moubachir, H; Zaghba, N; Benjelloun, H; Bakhatar, A; Yassine, N

2016-11-01

The management of a first episode of spontaneous pneumothorax is controversial and the best technique to be used as an initial intervention, aspiration or intercostal drainage, is still debated. We present a retrospective case series during two and a half consecutive years describing the immediate management of spontaneous pneumothoraces, comparing aspiration versus thoracic drainage. One hundred and thirty-three clinical files from patients with spontaneous pneumothoraces were analyzed (17 primary and 116 secondary). The pneumothoraces were of varying size and different etiologies. Patients were initially treated with simple aspiration in 68 cases, with an immediate success rate of 37.5%, intercostal drainage in 49 cases, and by rest alone in 16 cases. In case of secondary pneumothorax, aspiration appeared to offer advantages as an initial strategy over intercostal drainage in terms of hospital stay (11 versus 22 days), and with significant effectiveness (37.5%). Copyright © 2016 SPLF. Published by Elsevier Masson SAS. All rights reserved.

Spontaneous expulsive suprachoroidal hemorrhage caused by decompensated liver disease

Directory of Open Access Journals (Sweden)

Krishnagopal Srikanth

2013-01-01

Full Text Available Expulsive suprachoroidal hemorrhage can be surgical or spontaneous. Spontaneous expulsive suprachoroidal hemorrhage (SESCH is a rare entity. Most of the reported cases of SESCH were caused by a combination of corneal pathology and glaucoma. We are reporting a rare presentation of SESCH with no pre-existing glaucoma or corneal pathology and caused by massive intra- and peri-ocular hemorrhage due to decompensated liver disease.

Spontaneous emission of the non-Wiener type

International Nuclear Information System (INIS)

Basharov, A. M.

2011-01-01

The spontaneous emission of a quantum particle and superradiation of an ensemble of identical quantum particles in a vacuum electromagnetic field with zero photon density are examined under the conditions of significant Stark particle and field interaction. New fundamental effects are established: suppression of spontaneous emission by the Stark interaction, an additional “decay” shift in energy of the decaying level as a consequence of Stark interaction unrelated to the Lamb and Stark level shifts, excitation conservation phenomena in a sufficiently dense ensemble of identical particles and suppression of superradiaton in the decay of an ensemble of excited quantum particles of a certain density. The main equations describing the emission processes under conditions of significant Stark interaction are obtained in the effective Hamiltonian representation of quantum stochastic differential equations. It is proved that the Stark interaction between a single quantum particle and a broadband electromagnetic field is represented as a quantum Poisson process and the stochastic differential equations are of the non-Wiener (generalized Langevin) type. From the examined case of spontaneous emission of a quantum particle, the main rules are formulated for studying open systems in the effective Hamiltonian representation.

Spontaneously broken realization of supersymmetry in supergravity

International Nuclear Information System (INIS)

Ferrara, S.; Trieste Univ.

1979-01-01

It is shown that if supersymmetry is relevant for the physical world it must be broken either spontaneously or explicitly. Renormalizability and simplicity are in favor of a spontaneous realization of the symmetry breaking. When supersymmetry is spontaneously broken the spinorial analogue of the Goldstone phenomenon occurs, namely massless particles arise in the spectrum of the theory which carry the same quantum numbers of the broken generators Qsup(i) they are N spin 1/2 Goldstone fermions (goldstinos). These particles may be eaten by spin 3/2 gauge particles (gravitinos) when supersymmetry is gauged. It is shown that both the Higgs effect and super Higgs effect have taken place. 8 of the spin 1/2 particles have been eaten by the spin 3/2 particles and 24 of 70 scalars have been eaten by the spin 3/2 particles and 24 of 70 scalars have been eaten by 24 of the 28 vector particles to provide them with mass. The conclusion is that the number of mass relations is, in general, equal to r-1, where r is the rank of the algebra which generates the spectrum

Spontaneous Development of Moral Concepts

Science.gov (United States)

Siegal, M.

1975-01-01

Moral competence is more difficult to attain than scientific competence. Since language comprehension plays a central role in conceptual development, and moral language is difficult to learn, there is a common deficiency in moral conceptual development. This suggests a theory of non-spontaneous solutions to moral problems. (Author/MS)

Prediction of Spontaneous Preterm Birth

NARCIS (Netherlands)

Dijkstra, Karolien

2002-01-01

Preterm birth is a leading cause of neonatal morbidity and mortality. It is a major goal in obstetrics to lower the incidence of spontaneous preterm birth (SPB) and related neonatal morbidity and mortality. One of the principal objectives is to discover early markers that would allow us to identify

Spontaneous infarction of benign breast lesion during pregnancy: Ultrasonographic and pathologic findings

Energy Technology Data Exchange (ETDEWEB)

Kim, Jin Young; Kim, Kyu Soon; Kim, Ju Hun [Eulji University Hospital, Daejeon (Korea, Republic of); Lee, Yun Hak [Dept. of Radiology, Health Care Center, Pohang (Korea, Republic of)

2015-10-15

The spontaneous infarction of benign breast lesions is a rare entity and hence is not usually considered in the differential diagnosis during radiologic or clinical examination. There have been a few published cases of infarction during pregnancy and lactation. In this study we report the ultrasonographic and pathologic features of a spontaneous infarction of a lactating adenoma with acute mastitis and abscess and a spontaneously infarcted fibroadenoma.

Spontaneous infarction of benign breast lesion during pregnancy: Ultrasonographic and pathologic findings

International Nuclear Information System (INIS)

Kim, Jin Young; Kim, Kyu Soon; Kim, Ju Hun; Lee, Yun Hak

2015-01-01

The spontaneous infarction of benign breast lesions is a rare entity and hence is not usually considered in the differential diagnosis during radiologic or clinical examination. There have been a few published cases of infarction during pregnancy and lactation. In this study we report the ultrasonographic and pathologic features of a spontaneous infarction of a lactating adenoma with acute mastitis and abscess and a spontaneously infarcted fibroadenoma

Dynamics of entanglement between two atomic samples with spontaneous scattering

International Nuclear Information System (INIS)

Di Lisi, Antonio; De Siena, Silvio; Illuminati, Fabrizio

2004-01-01

We investigate the effects of spontaneous scattering on the evolution of entanglement of two atomic samples, probed by phase-shift measurements on optical beams interacting with both samples. We develop a formalism of conditional quantum evolutions and present a wave function analysis implemented in numerical simulations of the state vector dynamics. This method allows us to track the evolution of entanglement and to compare it with the predictions obtained when spontaneous scattering is neglected. We provide numerical evidence that the interferometric scheme to entangle atomic samples is only marginally affected by the presence of spontaneous scattering and should thus be robust even in more realistic situations

Spontaneous subdural hematoma associated to Duret hemorrhage

Directory of Open Access Journals (Sweden)

William Alves Martins, MD

2015-03-01

Full Text Available Subdural hematoma (SH is a neurosurgical emergency, usually caused by head trauma. Non-traumatic causes include aneurysm or arterial–venous malformation rupture, coagulopathy and others. We report the case of a 66 year-old man who developed apparently unprovoked signs of increased intracranial pressure. Brain computed tomography scan showed an acute spontaneous SH, surgically treated. Throughout surgery, a ruptured cortical artery with intensive bleeding appeared and was cauterized. After surgery, patient remained comatose and a new CT demonstrated Duret hemorrhage at the brainstem. Acute spontaneous SH of arterial origin is rare and highly lethal, in which a good prognosis relies on early diagnosis and treatment.

Bradycardia after Tube Thoracostomy for Spontaneous Pneumothorax

Directory of Open Access Journals (Sweden)

Yomi Fashola

2018-01-01

Full Text Available We present the case of an elderly patient who became bradycardic after chest tube insertion for spontaneous pneumothorax. Arrhythmia is a rare complication of tube thoracostomy. Unlike other reported cases of chest tube induced arrhythmias, the bradycardia in our patient responded to resuscitative measures without removal or repositioning of the tube. Our patient, who had COPD, presented with shortness of breath due to spontaneous pneumothorax. Moments after tube insertion, patient developed severe bradycardia that responded to Atropine. In patients requiring chest tube insertion, it is important to be prepared to provide cardiopulmonary resuscitative therapy in case the patient develops a life-threatening arrhythmia.

Detection of spontaneous combustion underground by measuring CO levels

Energy Technology Data Exchange (ETDEWEB)

Boutonnat, M; Jeger, M

1980-01-01

It is essential to detect spontaneous combustion as soon as it occurs so as to prevent such outbreaks from becoming a serious conflagration. At present CO detection is the basic method used. States the need for setting up additional measuring points (in air returns from working palces and in return airways in general). Where possible measuring instruments should be placed near zones where there is a particularly high risk of spontaneous combustion. Measurement should be undertaken on a continuous basis or as frequently as possible and must be capable of distinguishing between extraneous CO (shotfiring and diesel motors) and CO emanating from outbreaks of spontaneous combustion. The article describes two instruments developed by CERCHAR: the remote-control CO monitors type C and CSD. Both devices make use of a UNOR analyser.

Safety of Oral Clemastine – Analysis of Data from Spontaneous ...

African Journals Online (AJOL)

Purpose: To analyse the safety of oral clemastine marketed in Poland based on spontaneous adverse event reporting system. Methods: We analyzed sales volume and data obtained from the monitoring of spontaneous reports on the adverse effects of Clemastinum Hasco tablets (1.0 mg) and Clemastinum Hasco syrup (0.1 ...

Simulation of a flow spontaneously condensed moist steam in Laval nozzles

International Nuclear Information System (INIS)

Avetisyan, A.R.; Alipchenkov, V.M.; Zajchik, L.I.

2002-01-01

The method for simulating the evolution of the drops distribution by size in the course of commonly proceeding processes of nucleation (spontaneous condensation), heterogeneous condensation) evaporation and coagulation is proposed. The results of the analysis of the initial moisture effect on the steam spontaneous condensation in the transonic nozzles are presented. The availability of the minima in the output moisture dependences on the drops initial moisture and size is the most interesting result of the initial moisture effect on the spontaneous condensation in the Laval nozzles [ru

Endobronchial angiofibroma in the aberrant tracheal bronchus presenting as spontaneous pneumomediastinum.

Science.gov (United States)

Kim, Kyung Soo; Moon, Young Kyu; Jeon, Hyun Woo; Park, Chan Beom; Ahn, Myeong Im; Lee, Kyo Young; Park, Jae Kil

2015-07-22

Spontaneous pneumomediastinum is a self-limiting benign disease but abnormal bronchial lesions can be rarely found incidentally, and in selected cases will require surgical resection. A 38-year-old man presented with a spontaneous pneumomediastinum. Chest computed tomography revealed an incidental linear endobronchial tumour in the aberrant tracheal bronchus. The tumour was removed surgically and diagnosed with a rare benign tumour of endobronchial angiofibroma. We report a rare case of endobronchial angiofibroma in the aberrant tracheal bronchus which was detected during the evaluation of a spontaneous pneumomediastinum.

Spontaneous pneumothorax after intensive chemotherapy in endometrial cancer: A rare complication

Directory of Open Access Journals (Sweden)

Jen-Ruei Chen

2014-06-01

Conclusion: Rapid shrinkage of a pulmonary space-occupying tumor sometimes causes rare but life-threatening spontaneous pneumothoraces. We report the first case of a spontaneous pneumothorax after using paclitaxel plus carboplatin in the treatment of endometrial cancer.

Perturbation analysis of spontaneous action potential initiation by stochastic ion channels

KAUST Repository

Keener, James P.; Newby, Jay M.

2011-01-01

A stochastic interpretation of spontaneous action potential initiation is developed for the Morris-Lecar equations. Initiation of a spontaneous action potential can be interpreted as the escape from one of the wells of a double well potential

Effects of TRPV1 activation on synaptic excitation in the dentate gyrus of a mouse model of temporal lobe epilepsy.

Science.gov (United States)

Bhaskaran, Muthu D; Smith, Bret N

2010-06-01

Temporal lobe epilepsy (TLE) is a condition characterized by an imbalance between excitation and inhibition in the temporal lobe. Hallmarks of this change are axon sprouting and accompanying synaptic reorganization in the temporal lobe. Synthetic and endogenous cannabinoids have variable therapeutic potential in treating intractable temporal lobe epilepsy, in part because cannabinoid ligands can bind multiple receptor types. This study utilized in vitro electrophysiological methods to examine the effect of transient receptor potential vanilloid type 1 (TRPV1) activation in dentate gyrus granule cells in a murine model of TLE. Capsaicin, a selective TRPV1 agonist had no measurable effect on overall synaptic input to granule cells in control animals, but significantly enhanced spontaneous and miniature EPSC frequency in mice with TLE. Exogenous application of anandamide, an endogenous cannabinoid that acts at both TRPV1 and cannabinoid type 1 receptors (CB1R), also enhanced glutamate release in the presence of a CB1R antagonist. Anandamide reduced the EPSC frequency when TRPV1 were blocked with capsazepine. Western blot analysis of TRPV1 receptor indicated protein expression was significantly greater in the dentate gyrus of mice with TLE compared with control mice. This study indicates that a prominent cannabinoid agonist can increase excitatory circuit activity in the synaptically reorganized dentate gyrus of mice with TLE by activating TRPV1 receptors, and suggests caution in designing anticonvulsant therapy based on modulating the endocannabinoid system. Copyright (c) 2009 Elsevier Inc. All rights reserved.

Which nerve conduction parameters can predict spontaneous electromyographic activity in carpal tunnel syndrome?

Science.gov (United States)

Chang, Chia-Wei; Lee, Wei-Ju; Liao, Yi-Chu; Chang, Ming-Hong

2013-11-01

We investigate electrodiagnostic markers to determine which parameters are the best predictors of spontaneous electromyographic (EMG) activity in carpal tunnel syndrome (CTS). We enrolled 229 patients with clinically proven and nerve conduction study (NCS)-proven CTS, as well as 100 normal control subjects. All subjects were evaluated using electrodiagnostic techniques, including median distal sensory latencies (DSLs), sensory nerve action potentials (SNAPs), distal motor latencies (DMLs), compound muscle action potentials (CMAPs), forearm median nerve conduction velocities (FMCVs) and wrist-palm motor conduction velocities (W-P MCVs). All CTS patients underwent EMG examination of the abductor pollicis brevis (APB) muscle, and the presence or absence of spontaneous EMG activities was recorded. Normal limits were determined by calculating the means ± 2 standard deviations from the control data. Associations between parameters from the NCS and EMG findings were investigated. In patients with clinically diagnosed CTS, abnormal median CMAP amplitudes were the best predictors of spontaneous activity during EMG examination (p95% (positive predictive rate >95%). If the median CMAP amplitude was higher than the normal limit (>4.9 mV), the rate of no spontaneous EMG activity was >94% (negative predictive rate >94%). An abnormal SNAP amplitude was the second best predictor of spontaneous EMG activity (p<0.001; OR 4.13; 95% CI 2.16-7.90), and an abnormal FMCV was the third best predictor (p=0.01; OR 2.10; 95% CI 1.20-3.67). No other nerve conduction parameters had significant power to predict spontaneous activity upon EMG examination. The CMAP amplitudes of the APB are the most powerful predictors of the occurrence of spontaneous EMG activity. Low CMAP amplitudes are strongly associated with spontaneous activity, whereas high CMAP amplitude are less associated with spontaneous activity, implying that needle EMG examination should be recommended for the detection of

Spontaneous ovulation or male effect in alpacas and llamas

OpenAIRE

Sumar JB

2016-01-01

New discoveries in ovulation induced mammals, researchers considered the question of whether spontaneous and induced ovulations are distinct entities or individual parts of a single continuum of a “malefacilitated oestrus and ovulation”. This rigid classification should be taken with precaution, because is possible that the various mechanisms involved in the spontaneous ovulation can, under specific conditions coexist in some determined species. It is possible that male hormones can provoke t...

Spontaneous infarction of hyperplastic breast tissue: A case report

Energy Technology Data Exchange (ETDEWEB)

Yoo, Eun Young; Nam, Sang Yu; Choi, Hye Young; Hong, Min Ji [Dept. of Radiology, Gil Medical Center, Gachon University School of Medicine and Science, Incheon (Korea, Republic of)

2015-09-15

Spontaneous breast infarction is a very rare complication of fibroadenoma of the breast. We present an interesting case of a 33-year-old woman with spontaneous infarction of hyperplastic breast tissue related to pregnancy and lactation. Mammography showed an oval, circumscribed, fat-containing mass with microcalcifications. Ultrasonography revealed an oval, circumscribed mass with echogenic dots. Color Doppler imaging revealed presence of minimal vascularity at the periphery of the mass.

Recurrent Primary Spontaneous Pneumothorax is Common Following Chest Tube and Conservative Treatment

DEFF Research Database (Denmark)

Olesen, Winnie Hedevang; Lindahl-Jacobsen, Rune; Katballe, Niels

2016-01-01

INTRODUCTION: Previous studies on primary spontaneous pneumothorax reported variable recurrence rates, but they were based on heterogeneous patient populations including secondary pneumothorax. We investigated young patients with primary spontaneous pneumothorax exclusively and used a national...... registry to track readmissions and calculate independent predictors of recurrence. METHODS: A prospective cohort study of consecutive young patients who were admitted over a 5-year period with their first episode of primary spontaneous pneumothorax and treated conservatively with a chest tube. Baseline...... characteristics were obtained from questionnaires presented on admittance. All patients were discharged with fully expanded lungs on chest radiography. Patient charts were identified in the national electronic patient registry for detailed information on readmissions due to recurrent spontaneous pneumothorax...

Synaptic model for spontaneous activity in developing networks

DEFF Research Database (Denmark)

Lerchner, Alexander; Rinzel, J.

2005-01-01

Spontaneous rhythmic activity occurs in many developing neural networks. The activity in these hyperexcitable networks is comprised of recurring "episodes" consisting of "cycles" of high activity that alternate with "silent phases" with little or no activity. We introduce a new model of synaptic...... dynamics that takes into account that only a fraction of the vesicles stored in a synaptic terminal is readily available for release. We show that our model can reproduce spontaneous rhythmic activity with the same general features as observed in experiments, including a positive correlation between...

Characterizing spontaneous irregular behavior in coupled map lattices

International Nuclear Information System (INIS)

Dobyns, York; Atmanspacher, Harald

2005-01-01

Two-dimensional coupled map lattices display, in a specific parameter range, a stable phase (quasi-) periodic in both space and time. With small changes to the model parameters, this stable phase develops spontaneous eruptions of non-periodic behavior. Although this behavior itself appears irregular, it can be characterized in a systematic fashion. In particular, parameter-independent features of the spontaneous eruptions may allow useful empirical characterizations of other phenomena that are intrinsically hard to predict and reproduce. Specific features of the distributions of lifetimes and emergence rates of irregular states display such parameter-independent properties

Characterizing spontaneous irregular behavior in coupled map lattices

Energy Technology Data Exchange (ETDEWEB)

Dobyns, York [PEAR, Princeton University Princeton, NJ 08544-5263 (United States); Atmanspacher, Harald [Institut fuer Grenzgebiete der Psychologie und Psychohygiene Wilhelmstrasse 3a, Freiburg 79098 (Germany)]. E-mail: haa@igpp.de

2005-04-01

Two-dimensional coupled map lattices display, in a specific parameter range, a stable phase (quasi-) periodic in both space and time. With small changes to the model parameters, this stable phase develops spontaneous eruptions of non-periodic behavior. Although this behavior itself appears irregular, it can be characterized in a systematic fashion. In particular, parameter-independent features of the spontaneous eruptions may allow useful empirical characterizations of other phenomena that are intrinsically hard to predict and reproduce. Specific features of the distributions of lifetimes and emergence rates of irregular states display such parameter-independent properties.

Spontaneous compactification and Ricci-flat manifolds with torsion

International Nuclear Information System (INIS)

McInnes, B.

1985-06-01

The Freund-Rubin mechanism is based on the equation Rsub(ik)=lambdagsub(ik) (where lambda>0), which, via Myers' Theorem, implies ''spontaneous'' compactification. The difficulties connected with the cosmological constant in this approach can be resolved if torsion is introduced and lambda set equal to zero, but then compactification ''by hand'' is necessary, since the equation Rsub(ik)=0 can be satisfied both on compact and on non-compact manifolds. In this paper we discuss the global geometry of Ricci-flat manifolds with torsion, and suggest ways of restoring the ''spontaneity'' of the compactification. (author)

Spontaneous symmetry breaking, self-trapping, and Josephson oscillations

CERN Document Server

2013-01-01

This volume collects a a number of contributions on spontaneous symmetry breaking. Current studies in this general field are going ahead at a full speed. The book present review chapters which give an overview on the major break throughs of recent years. It covers a number of different physical settings which are introduced when a nonlinearity is added to the underlying symmetric problems and its strength exceeds a certain critical value. The corresponding loss of symmetry, called spontaneous symmetry breaking, alias self-trapping into asymmetric states is extensively discussed in this book.

Nonclassical photon streams using rephased amplified spontaneous emission

International Nuclear Information System (INIS)

Ledingham, Patrick M.; Naylor, William R.; Longdell, Jevon J.; Beavan, Sarah E.; Sellars, Matthew J.

2010-01-01

We present a fully quantum mechanical treatment of optically rephased photon echoes. These echoes exhibit noise due to amplified spontaneous emission; however, this noise can be seen as a consequence of the entanglement between the atoms and the output light. With a rephasing pulse one can get an 'echo' of the amplified spontaneous emission, leading to light with nonclassical correlations at points separated in time, which is of interest in the context of building wide bandwith quantum repeaters. We also suggest a wideband version of DLCZ protocol based on the same ideas.

Spontaneous drainage in syringomyelia: magnetic resonance imaging findings

International Nuclear Information System (INIS)

Bogdanov, E.I.; Mendelevich, E.G.; Ibatullin, M.M.

2000-01-01

We present five cases of syringomyelia associated with Chiari I or other causes of partial obstructions at the cervicomedullary junction, with spontaneous disruption of the wall of a cervical syrinx and formation of a communication between the cavity and the subarachnoid space, shown on axial MRI. MRI can be used to investigate the hydrodynamics, showing the liquid inside the disrupted syrinx wall and the pathway of drainage. The finding of spontaneous drainage may be important for understanding the pathogenesis of syringomyelia and may be helpful for choosing a surgical approach. (orig.)

Spontaneous drainage in syringomyelia: magnetic resonance imaging findings

Energy Technology Data Exchange (ETDEWEB)

Bogdanov, E.I.; Mendelevich, E.G. [Kazan State Medical Univ. (Russian Federation). Dept. of Neurology and Rehabilitation; Ibatullin, M.M. [Republic Medical Diagnostic Centre of Tatarstan, Kazan (Russian Federation). Department of Radiology

2000-09-01

We present five cases of syringomyelia associated with Chiari I or other causes of partial obstructions at the cervicomedullary junction, with spontaneous disruption of the wall of a cervical syrinx and formation of a communication between the cavity and the subarachnoid space, shown on axial MRI. MRI can be used to investigate the hydrodynamics, showing the liquid inside the disrupted syrinx wall and the pathway of drainage. The finding of spontaneous drainage may be important for understanding the pathogenesis of syringomyelia and may be helpful for choosing a surgical approach. (orig.)

Plasticity of calcium-permeable AMPA glutamate receptors in Pro-opiomelanocortin neurons.

Science.gov (United States)

Suyama, Shigetomo; Ralevski, Alexandra; Liu, Zhong-Wu; Dietrich, Marcelo O; Yada, Toshihiko; Simonds, Stephanie E; Cowley, Michael A; Gao, Xiao-Bing; Diano, Sabrina; Horvath, Tamas L

2017-08-01

POMC neurons integrate metabolic signals from the periphery. Here, we show in mice that food deprivation induces a linear current-voltage relationship of AMPAR-mediated excitatory postsynaptic currents (EPSCs) in POMC neurons. Inhibition of EPSCs by IEM-1460, an antagonist of calcium-permeable (Cp) AMPARs, diminished EPSC amplitude in the fed but not in the fasted state, suggesting entry of GluR2 subunits into the AMPA receptor complex during food deprivation. Accordingly, removal of extracellular calcium from ACSF decreased the amplitude of mEPSCs in the fed but not the fasted state. Ten days of high-fat diet exposure, which was accompanied by elevated leptin levels and increased POMC neuronal activity, resulted in increased expression of Cp-AMPARs on POMC neurons. Altogether, our results show that entry of calcium via Cp-AMPARs is inherent to activation of POMC neurons, which may underlie a vulnerability of these neurons to calcium overload while activated in a sustained manner during over-nutrition.

Do static atoms outside a Schwarzschild black hole spontaneously excite?

International Nuclear Information System (INIS)

Yu Hongwei; Zhou Wenting

2007-01-01

The spontaneous excitation of a two-level atom held static outside a four dimensional Schwarzschild black hole and in interaction with a massless scalar field in the Boulware, Unruh, and Hartle-Hawking vacuums is investigated, and the contributions of the vacuum fluctuations and radiation reaction to the rate of change of the mean atomic energy are calculated separately. We find that, for the Boulware vacuum, the spontaneous excitation does not occur and the ground-state atoms are stable, while the spontaneous emission rate for excited atoms in the Boulware vacuum, which is well behaved at the event horizon, is not the same as that in the usual Minkowski vacuum. However, for both the Unruh vacuum and the Hartle-Hawking vacuum, our results show that the atom would spontaneously excite, as if there were an outgoing thermal flux of radiation or as if it were in a thermal bath of radiation at a proper temperature which reduces to the Hawking temperature in the spatial asymptotic region, depending on whether the scalar field is in the Unruh or Hartle-Hawking vacuum

Spontaneous Clearance of Hepatitis C after Liver and Renal Transplantation

Directory of Open Access Journals (Sweden)

CH Dale

2009-01-01

Full Text Available Spontaneous clearance of hepatitis C virus (HCV is rare in immunocompromised patients, such as those who have undergone organ transplantation. It has been recognized that patients receiving liver transplantation for HCV-related disease have decreased graft and patient survival compared with those transplanted for other etiologies. There is a growing trend toward treating HCV recurrence aggressively after liver transplantation. For other organ transplant recipients with concurrent HCV, treatment is not often an option, given the high rates of graft rejection and loss secondary to interferon and its immunomodulatory effects. Although spontaneous clearance of HCV has been reported in recipients of solitary liver and renal transplants, a common factor arising in these cases has been previous exposure to interferon. To date, no reports of spontaneous clearance of HCV RNA have been reported in a multiorgan transplant recipient. A case of spontaneous clearance of HCV RNA in an immunocompromised patient, within five months of simultaneous liver and kidney retransplantation is described. Importantly, this patient had no previous exposure to interferon.

Regulation of Spontaneous Eosinophil Apoptosis—A Neglected Area of Importance

Directory of Open Access Journals (Sweden)

Pinja Ilmarinen

2014-01-01

Full Text Available Asthma is characterized by the accumulation of eosinophils in the airways in most phenotypes. Eosinophils are inflammatory cells that require an external survival-prolonging stimulus such as granulocyte macrophage-colony-stimulating factor (GM-CSF, interleukin (IL-5, or IL-3 for survival. In their absence, eosinophils are programmed to die by spontaneous apoptosis in a few days. Eosinophil apoptosis can be accelerated by Fas ligation or by pharmacological agents such as glucocorticoids. Evidence exists for the relevance of these survival-prolonging and pro-apoptotic agents in the regulation of eosinophilic inflammation in inflamed airways. Much less is known about the physiological significance and mechanisms of spontaneous eosinophil apoptosis even though it forms the basis of regulation of eosinophil longevity by pathophysiological factors and pharmacological agents. This review concentrates on discussing the mechanisms of spontaneous eosinophil apoptosis compared to those of glucocorticoid- and Fas-induced apoptosis. We aim to answer the question whether the external apoptotic stimuli only augment the ongoing pathway of spontaneous apoptosis or truly activate a specific pathway.

Spontaneous common bile duct perforation—A rare clinical entity

Directory of Open Access Journals (Sweden)

Melissa Amberger

Full Text Available Introduction: Spontaneous common bile duct perforation is an uncommon clinical entity in both adults and children. Few case reports have been published since the first clinical description in 1882. Our work has been reported in line with SCARE criteria. Presentation of case: Herein, we describe the case of a 28 year-old female who suffered spontaneous common bile duct perforation while admitted for choledocholithiasis. Discussion: The perforation occurred while in-hospital, and extensive imaging and laboratory tests characterized the disease in detail. To our knowledge, this is the first report of spontaneous common bile duct perforation witnessed from pre-perforation through definitive management. Conclusion: Physicians and Surgeons should seek out this uncommon diagnosis in the patient with suspected Choledocholithiasis who suddenly become peritoneal on physical exam so that definitive care can be expedited. Keywords: Common bile duct, Biliary peritonitis, Choledocholithiasis

Prospective memory: effects of divided attention on spontaneous retrieval.

Science.gov (United States)

Harrison, Tyler L; Mullet, Hillary G; Whiffen, Katie N; Ousterhout, Hunter; Einstein, Gilles O

2014-02-01

We examined the effects of divided attention on the spontaneous retrieval of a prospective memory intention. Participants performed an ongoing lexical decision task with an embedded prospective memory demand, and also performed a divided-attention task during some segments of lexical decision trials. In all experiments, monitoring was highly discouraged, and we observed no evidence that participants engaged monitoring processes. In Experiment 1, performing a moderately demanding divided-attention task (a digit detection task) did not affect prospective memory performance. In Experiment 2, performing a more challenging divided-attention task (random number generation) impaired prospective memory. Experiment 3 showed that this impairment was eliminated when the prospective memory cue was perceptually salient. Taken together, the results indicate that spontaneous retrieval is not automatic and that challenging divided-attention tasks interfere with spontaneous retrieval and not with the execution of a retrieved intention.

Spontaneous Plasticity of Multineuronal Activity Patterns in Activated Hippocampal Networks

Directory of Open Access Journals (Sweden)

Atsushi Usami

2008-01-01

Full Text Available Using functional multineuron imaging with single-cell resolution, we examined how hippocampal networks by themselves change the spatiotemporal patterns of spontaneous activity during the course of emitting spontaneous activity. When extracellular ionic concentrations were changed to those that mimicked in vivo conditions, spontaneous activity was increased in active cell number and activity frequency. When ionic compositions were restored to the control conditions, the activity level returned to baseline, but the weighted spatial dispersion of active cells, as assessed by entropy-based metrics, did not. Thus, the networks can modify themselves by altering the internal structure of their correlated activity, even though they as a whole maintained the same level of activity in space and time.

Recanalisation of spontaneously occluded vertebral artery dissection after subarachnoid haemorrhage.

Science.gov (United States)

Akiyama, Takenori; Onozuka, Satoshi; Horiguchi, Takashi; Yoshida, Kazunari

2012-10-01

Spontaneous occlusion is a rare manifestation of ruptured vertebral artery dissection (VAD). Its natural history and treatment strategy have yet to be established due to its rarity. Here, we report five lesions involving spontaneous occlusion of VAD after subarachnoid haemorrhage, among which three lesions showed recanalisation. Based on our experience and previous reports, spontaneous occlusion of ruptured VAD can be classified into two groups-one group with occlusion in the acute stage with a high incidence of recanalisation and another group with occlusion in the chronic stage with a relatively low incidence of recanalisation. The underlying mechanism is likely different in each group, and treatment strategies should also be tailored depending on the pathophysiology.

Spontane abdominale arteriovenøse fistler

DEFF Research Database (Denmark)

Flarup, S; Lindholt, Jes Sanddal

1997-01-01

Spontaneous arteriovenous fistulas between major abdominal vessels (AAVF) complicates about 1% of abdominal aortic aneurysms. AAVF produces severe circulatory disturbances with high operative mortality. Preoperative diagnosis is important but difficult due to the varied nature of presentation. Fo...

Measuring emotional and cognitive empathy using dynamic, naturalistic, and spontaneous emotion displays.

Science.gov (United States)

Buck, Ross; Powers, Stacie R; Hull, Kyle S

2017-10-01

Most measures of nonverbal receiving ability use posed expressions as stimuli. As empathy measures, such stimuli lack ecological validity, as the participant is not actually experiencing emotion. An alternative approach uses natural and dynamic displays of spontaneous expressions. The Communication of Affect Receiving Ability Test (CARAT) uses as stimuli spontaneous facial expressions and gestures filmed by an unobtrusive camera of solitary participants responding to emotional images. This article reports the development and initial validation of the CARAT-Spontaneous, Posed, Regulated (CARAT-SPR), which measures both abilities to detect emotion from spontaneous displays (emotion communication accuracy) and to differentiate spontaneous, posed, and regulated displays (expression categorization ability). Although spontaneous displays are natural responses to emotional images, posed displays involve asking the sender to display "as if" responding to a particular sort of image when no image is in fact present (simulation), while Regulated displays involve asking the sender to display "as if" responding to a particular sort of image when an image of opposite valence is in fact present (masking). Expression categorization ability involves judging deception-simulation and masking-and conceptually involves a kind of perspective-taking or cognitive empathy. Emotion communication using spontaneous clips achieved a high level of accuracy and was strongly correlated with ratings of sender expressivity. Expression categorization ability was not significantly correlated with expressivity ratings and was modestly negatively correlated with emotion communication accuracy. In a brief version of the CARAT-SPR, women showed evidence of greater emotion signal detection, whereas men reported greater confidence in expression categorization. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Spontaneous Tricuspid Valve Chordal Rupture in Idiopathic Pulmonary Hypertension.

Science.gov (United States)

Rodrigues, Ana Clara Tude; Afonso, José E; Cordovil, Adriana; Monaco, Claudia; Piveta, Rafael; Cordovil, Rodrigo; Fischer, Claudio H; Vieira, Marcelo; Lira-Filho, Edgar; Morhy, Samira S

2016-03-01

Rupture of tricuspid valve is unusual, occurring mainly in the setting of blunt trauma or endomyocardial biopsy. Spontaneous tricuspid valve chordal rupture is particularly rare. We report herein a case of a patient with severe pulmonary hypertension, on the lung transplantation waiting list, who presented with spontaneous chordal rupture, exacerbation of tricuspid insufficiency and worsening of clinical status. Diagnosis and treatment, along with possible mechanisms for this complication, are discussed. © 2015, Wiley Periodicals, Inc.

Spontaneous Responses to Neoliberalism, and their Significance for Education

Directory of Open Access Journals (Sweden)

Johannes L van der Walt

2017-05-01

Full Text Available This paper is a sequel to the keynote address at the 2017 BCES Conference. The keynote address concluded with the thought that some educationists respond intuitively and spontaneously to neoliberalism and its impact on education whereas others reject neoliberalist precepts and their pedagogical implications on definite principled grounds. This paper deals with the former response; it offers pedagogical insights gleaned from an overview of intuitive, spontaneous reactions to neoliberalism.

Highly Efficient Spontaneous Emission from Self-Assembled Quantum Dots

DEFF Research Database (Denmark)

Johansen, Jeppe; Lund-Hansen, Toke; Hvam, Jørn Märcher

2006-01-01

We present time resolved measurements of spontaneous emission (SE) from InAs/GaAs quantum dots (QDs). The measurements are interpreted using Fermi's Golden Rule and from this analysis we establish the parameters for high quantum efficiency.......We present time resolved measurements of spontaneous emission (SE) from InAs/GaAs quantum dots (QDs). The measurements are interpreted using Fermi's Golden Rule and from this analysis we establish the parameters for high quantum efficiency....

Simulation investigation of storage ring optical klystron spontaneous emission

International Nuclear Information System (INIS)

Xu Hongliang; Liu Jinying; He Duohui; Diao Caozheng; Jia Qika; Sun Baogen

1998-01-01

The spontaneous emission of TOK in Hefei storage ring was simulated with Monte Carlo method. Section one described the structure of the permanent magnet TOK and the magnet field of TOK. Section two simulated results, and simulated results illustrated how the energy spread and emittance of electron beam impose on the spectrum of spontaneous emission. And with help of simulated results, the causes of small modulation factor which was measured by experiment was discussed

Spontaneous herniation of the thoracic spinal cord : a case report

International Nuclear Information System (INIS)

Jin, Sung Chan; Lee, Seong Ro; Park, Dong Woo; Joo, Kyung Bin

2001-01-01

Spontaneous herniation of the spinal cord is a rare disease entity in which spinal cord substance is herniated through a previously uninjured and/or untouched dural. It is a cause of myelopathy that is treatable but difficult to diagnose. We report the CT and MR findings of a case of spontaneous thoracic spinal cord through a dural defect

Synaptotagmin-7 Is an Asynchronous Calcium Sensor for Synaptic Transmission in Neurons Expressing SNAP-23

DEFF Research Database (Denmark)

Weber, Jens P; Toft-Bertelsen, Trine L; Mohrmann, Ralf

2014-01-01

Synchronization of neurotransmitter release with the presynaptic action potential is essential for maintaining fidelity of information transfer in the central nervous system. However, synchronous release is frequently accompanied by an asynchronous release component that builds up during repetitive...... stimulation, and can even play a dominant role in some synapses. Here, we show that substitution of SNAP-23 for SNAP-25 in mouse autaptic glutamatergic hippocampal neurons results in asynchronous release and a higher frequency of spontaneous release events (mEPSCs). Use of neurons from double-knock-out (SNAP......, while synaptotagmin-7 barely displayed activity-dependent trafficking between vesicle and plasma membrane, implying that it acts as a plasma membrane calcium sensor. Overall, these findings support the idea of alternative syt∶SNARE combinations driving release with different kinetics and fidelity....

Spontaneous symmetry breakdown in gauge theories

International Nuclear Information System (INIS)

Scadron, M.D.

1982-01-01

The dynamical theory of spontaneous breakdown correctly predicts the bound states and relates the order parameters of electron-photon superconductivity and quark-gluon chiral symmetry. A similar statement cannot be made for the standard electro-weak gauge symmetry. (author)

Spontaneous Spreading of a Droplet: The Role of Solid Continuity and Advancing Contact Angle.

Science.gov (United States)

Jiang, Youhua; Sun, Yujin; Drelich, Jaroslaw W; Choi, Chang-Hwan

2018-05-01

Spontaneous spreading of a droplet on a solid surface is poorly understood from a macroscopic level down to a molecular level. Here, we investigate the effect of surface topography and wettability on spontaneous spreading of a water droplet. Spreading force is measured for a suspended droplet that minimizes interference of kinetic energy in the spontaneous spreading during its contact with solid surfaces of discontinuous (pillar) and continuous (pore) patterns with various shapes and dimensions. Results show that a droplet cannot spread spontaneously on pillared surfaces regardless of their shapes or dimensions because of the solid discontinuity. On the contrary, a droplet on pored surfaces can undergo spontaneous spreading whose force increases with a decrease in the advancing contact angle. Theoretical models based on both the system free energy and capillary force along the contact line validate the direct and universal dependency of the spontaneous spreading force on the advancing contact angle.

Spontaneous Wave Generation from Submesoscale Fronts and Filaments

Science.gov (United States)

Shakespeare, C. J.; Hogg, A.

2016-02-01

Submesoscale features such as eddies, fronts, jets and filaments can be significant sources of spontaneous wave generation at the ocean surface. Unlike near-inertial waves forced by winds, these spontaneous waves are typically of higher frequency and can propagate through the thermocline, whereupon they break and drive mixing in the ocean interior. Here we investigate the spontaneous generation, propagation and subsequent breaking of these waves using a combination of theory and submesoscale resolving numerical models. The mechanism of generation is nearly identical to that of lee waves where flow is deflected over a rigid obstacle on the sea floor. Here, very sharp fronts and filaments of order 100m width moving in the submesoscale surface flow generate "surface lee waves" by presenting an obstacle to the surrounding stratified fluid. Using our numerical model we quantify the net downward wave energy flux from the surface, and where it is dissipated in the water column. Our results suggest an alternative to the classical paradigm where the energy associated with mixing in the ocean interior is sourced from bottom-generated lee waves.

Spontaneous group synchronization of movements and respiratory rhythms.

Directory of Open Access Journals (Sweden)

Erwan Codrons

Full Text Available We tested whether pre-assigned arm movements performed in a group setting spontaneously synchronized and whether synchronization extended to heart and respiratory rhythms. We monitored arm movements, respiration and electrocardiogram at rest and during spontaneous, music and metronome-associated arm-swinging. No directions were given on whether or how the arm swinging were to be synchronized between participants or with the external cues. Synchronization within 3 groups of 10 participants studied collectively was compared with pseudo-synchronization of 3 groups of 10 participants that underwent an identical protocol but in an individual setting. Motor synchronization was found to be higher in the collective groups than in the individuals for the metronome-associated condition. On a repetition of the protocol on the following day, motor synchronization in the collective groups extended to the spontaneous, un-cued condition. Breathing was also more synchronized in the collective groups than in the individuals, particularly at rest and in the music-associated condition. Group synchronization occurs without explicit instructions, and involves both movements and respiratory control rhythms.

A case of a spontaneously ruptured epidermoid cyst

International Nuclear Information System (INIS)

Shiroyama, Yujiro; Saiki, Masahide; Ueda, Hiroyuki; Katayama, Sanao; Mitani, Tetsumi

1987-01-01

Intracranial fat-containing congenital tumors are characterized by negative absorption values on CT. We hereby report a case of an epidermoid cyst with subarachnoid free fats diagnosed preoperatively by CT. A 21-year-old female was admitted to our hospital because of continuous mild headache and nausea. At the time of admission, the results of her physical and neurological examinations were normal. CT, however, demonstrated multiple subarachnoid low-density spots and a suprasellar low-density area with high-density spots. In addition, there were negative absorption values (-12 ∼ -77), suggesting free fats. A spontaneously ruptured epidermoid or dermoid cyst was diagnosed on the basis of these findings. At surgery, a suprasellar tumor containing a yellowish, cheese-like material was confirmed. The patient made an uneventful recovery and was discharged 14 days after surgery. There have been several published reports of CT appearances of intracranial fat-containing tumors. However, spontaneously ruptured cases diagnosed by CT are rare. CT was found to be useful for the diagnosis of spontaneously ruptured cases of fat-containing tumors. (author)

Impaired insulin secretion in the spontaneous diabetes rats.

Science.gov (United States)

Kimura, K; Toyota, T; Kakizaki, M; Kudo, M; Takebe, K; Goto, Y

1982-08-01

Dynamics of insulin and glucagon secretion were investigated by using a new model of spontaneous diabetes rats produced by the repetition of selective breeding in our laboratories. The perfusion experiments of the pancreas showed that the early phase of insulin secretion to continuous stimulation with glucose was specifically impaired, although the response of the early phase to arginine was preserved. The glucose-induced insulin secretion in the nineth generation (F8) which had a more remarkably impaired glucose tolerance was more reduced than in the sixth generation (F5). No significant difference of glucagon secretion in response to arginine or norepinephrine was noted between the diabetes rats and control ones. The present data indicate that the defective insulin secretion is a primary derangement in a diabetic state of the spontaneous diabetes rat. This defect in the early phase of glucose-induced insulin secretion suggests the specific impairment of the recognition of glucose by the pancreatic beta-cells. The spontaneous diabetes rats are very useful as a model of disease for investigating pathophysiology of non-insulin dependent diabetes mellitus.

Spontaneous intracranial hypotension

International Nuclear Information System (INIS)

Cardwell, C.; Cox, I.; Baldey, A.

2002-01-01

Full text: A 49-year old female presented with severe postural headache with no history of trauma. A Computed Tomography (CT) study of the brain demonstrated abnormal meningeal enhancement raising the possibility of leptomeningeal metastases. The patient was then referred to Magnetic Resonance Imaging (MRI) which demonstrated diffuse smooth dural enhancement with ancillary findings characteristic of spontaneous intracranial hypotension. The patient was then referred to Nuclear Medicine to confirm the diagnosis and localise the presumed leak 400MBq of 99mTc DTPA was injected via lumbar puncture into the L3-L4 subarachnoid space Posterior images of the spine were taken with a GE XRT single head gamma camera at 1 and 4 hours post administration of radionuclide. Images demonstrated abnormal early arrival of radionuclide in the kidneys and bladder at 1 hour and abnormal leak of tracer was demonstrate at the level of the first thoracic vertebra on the right side at 4 hours. This confirmed CSF leak at this level. Consequently the patient underwent a blood patch and her symptoms resolved. Spontaneous Intracranial Hypotension is a syndrome often unrecognised presenting with symptoms including severe postural headache neck stiffness nausea vomiting tinnitus and vertigo. The diagnosis is frequently suspected from findings on MRI, but Nuclear Medicine CSF imaging provides a readily available and cost effective method for confirming the diagnosis, and for making the diagnosis in patients who are unsuitable for or do not have access to MRI. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

Spontaneous intracranial hypotension

Energy Technology Data Exchange (ETDEWEB)

Cardwell, C; Cox, I; Baldey, A [St. F.X. Cabrini Hospital, VIC (Australia). Departments of Nuclear Medicine and Magnetic Resonance Imaging

2002-07-01

Full text: A 49-year old female presented with severe postural headache with no history of trauma. A Computed Tomography (CT) study of the brain demonstrated abnormal meningeal enhancement raising the possibility of leptomeningeal metastases. The patient was then referred to Magnetic Resonance Imaging (MRI) which demonstrated diffuse smooth dural enhancement with ancillary findings characteristic of spontaneous intracranial hypotension. The patient was then referred to Nuclear Medicine to confirm the diagnosis and localise the presumed leak 400MBq of 99mTc DTPA was injected via lumbar puncture into the L3-L4 subarachnoid space Posterior images of the spine were taken with a GE XRT single head gamma camera at 1 and 4 hours post administration of radionuclide. Images demonstrated abnormal early arrival of radionuclide in the kidneys and bladder at 1 hour and abnormal leak of tracer was demonstrate at the level of the first thoracic vertebra on the right side at 4 hours. This confirmed CSF leak at this level. Consequently the patient underwent a blood patch and her symptoms resolved. Spontaneous Intracranial Hypotension is a syndrome often unrecognised presenting with symptoms including severe postural headache neck stiffness nausea vomiting tinnitus and vertigo. The diagnosis is frequently suspected from findings on MRI, but Nuclear Medicine CSF imaging provides a readily available and cost effective method for confirming the diagnosis, and for making the diagnosis in patients who are unsuitable for or do not have access to MRI. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc.

TRPV1 marks synaptic segregation of multiple convergent afferents at the rat medial solitary tract nucleus.

Directory of Open Access Journals (Sweden)

James H Peters

Full Text Available TRPV1 receptors are expressed on most but not all central terminals of cranial visceral afferents in the caudal solitary tract nucleus (NTS. TRPV1 is associated with unmyelinated C-fiber afferents. Both TRPV1+ and TRPV1- afferents enter NTS but their precise organization remains poorly understood. In horizontal brainstem slices, we activated solitary tract (ST afferents and recorded ST-evoked glutamatergic excitatory synaptic currents (ST-EPSCs under whole cell voltage clamp conditions from neurons of the medial subnucleus. Electrical shocks to the ST produced fixed latency EPSCs (jitter<200 µs that identified direct ST afferent innervation. Graded increases in shock intensity often recruited more than one ST afferent and ST-EPSCs had consistent threshold intensity, latency to onset, and unique EPSC waveforms that characterized each unitary ST afferent contact. The TRPV1 agonist capsaicin (100 nM blocked the evoked TRPV1+ ST-EPSCs and defined them as either TRPV1+ or TRPV1- inputs. No partial responses to capsaicin were observed so that in NTS neurons that received one or multiple (2-5 direct ST afferent inputs--all were either blocked by capsaicin or were unaltered. Since TRPV1 mediates asynchronous release following TRPV1+ ST-evoked EPSCs, we likewise found that recruiting more than one ST afferent further augmented the asynchronous response and was eliminated by capsaicin. Thus, TRPV1+ and TRPV1- afferents are completely segregated to separate NTS neurons. As a result, the TRPV1 receptor augments glutamate release only within unmyelinated afferent pathways in caudal medial NTS and our work indicates a complete separation of C-type from A-type afferent information at these first central neurons.

Intake of probiotic food and risk of spontaneous preterm delivery123

Science.gov (United States)

Myhre, Ronny; Brantsæter, Anne Lise; Myking, Solveig; Gjessing, Håkon Kristian; Sengpiel, Verena; Meltzer, Helle Margrete; Haugen, Margaretha; Jacobsson, Bo

2011-01-01

Background: Preterm delivery represents a substantial problem in perinatal medicine worldwide. Current knowledge on potential influences of probiotics in food on pregnancy complications caused by microbes is limited. Objective: We hypothesized that intake of food with probiotics might reduce pregnancy complications caused by pathogenic microorganisms and, through this, reduce the risk of spontaneous preterm delivery. Design: This study was performed in the Norwegian Mother and Child Cohort on the basis of answers to a food-frequency questionnaire. We studied intake of milk-based products containing probiotic lactobacilli and spontaneous preterm delivery by using a prospective cohort study design (n = 950 cases and 17,938 controls) for the pregnancy outcome of spontaneous preterm delivery (<37 gestational weeks). Analyses were adjusted for the covariates of parity, maternal educational level, and physical activity. Results: Pregnancies that resulted in spontaneous preterm delivery were associated with any intake of milk-based probiotic products in an adjusted model [odds ratio (OR): 0.857; 95% CI: 0.741, 0.992]. By categorizing intake into none, low, and high intakes of the milk-based probiotic products, a significant association was observed for high intake (OR: 0.820; 95% CI: 0.681, 0.986). Conclusion: Women who reported habitual intake of probiotic dairy products had a reduced risk of spontaneous preterm delivery. PMID:20980489

Spontaneous emergence of free-space optical and atomic patterns

International Nuclear Information System (INIS)

Schmittberger, Bonnie L; Gauthier, Daniel J

2016-01-01

The spontaneous formation of patterns in dynamical systems is a rich phenomenon that transcends scientific boundaries. Here, we report our observation of coupled optical–atomic pattern formation, which results in the creation of self-organized, multimode structures in free-space laser-driven cold atoms. We show that this process gives rise to spontaneous three-dimensional Sisyphus cooling even at very low light intensities and the emergence of self-organized structures on both sub- and super-wavelength scales. (paper)

Treatment of ascites and spontaneous bacterial peritonitis - Part I

DEFF Research Database (Denmark)

Bendtsen, Flemming; Grønbæk, Henning; Hansen, Jesper Bach

2012-01-01

National guidelines for treatment of ascites, spontaneous bacterial peritonitis, hepatorenal syndrome, and hyponatremia have been approved by the Danish Society of Gastroenterology and Hepatology. Ascites develops in approximately 60% of patients with cirrhosis during a 10 year period and is freq......National guidelines for treatment of ascites, spontaneous bacterial peritonitis, hepatorenal syndrome, and hyponatremia have been approved by the Danish Society of Gastroenterology and Hepatology. Ascites develops in approximately 60% of patients with cirrhosis during a 10 year period...

Functional characterization of Foxp3-specific spontaneous immune responses

DEFF Research Database (Denmark)

Larsen, Susanne Købke; Munir, S; Andersen, Anders Woetmann

2013-01-01

Tumor-infiltrating CD4+CD25+ regulatory T cells (Tregs) are associated with an impaired prognosis in several cancers. The transcription factor forkhead box P3 (Foxp3) is generally expressed in Tregs. Here, we identify and characterize spontaneous cytotoxic immune responses to Foxp3-expressing cel....... Consequently, induction of Foxp3-specific cytotoxic T-cell responses appears as an attractive tool to boost spontaneous or therapeutically provoked immune responses, for example, for the therapy of cancer....

[Difference between perinatal mortality in multiple pregnancies obtained spontaneously versus assisted reproduction].

Science.gov (United States)

del Rayo Rivas-Ortiz, Yazmín; Hernández-Herrera, Ricardo Jorge

2010-06-01

Recently assisted reproduction techniques are more common, which increases multiple pregnancies and adverse perinatal outcomes. Some authors report increased mortality in multiple pregnancies products obtained by techniques of assisted reproduction vs. conceived spontaneously, although other authors found no significant difference. To evaluate mortality rate of multiple pregnancies comparing those obtained by assisted reproduction vs. spontaneous conception. Retrospective, observational and comparative study. We included pregnant women with 3 or more products that went to the Unidad Médica de Alta Especialidad No. 23, IMSS, in Monterrey, NL (Mexico), between 2002-2008. We compared the number of complicated pregnancies and dead products obtained by a technique of assisted reproduction vs. spontaneous. 68 multiple pregnancies were included. On average, spontaneously conceived fetuses had more weeks of gestation and more birth weight than those achieved by assisted reproduction techniques (p = ns). 20.5% (14/68) of multiple pregnancies had one or more fatal events: 10/40 (25%) by assisted reproduction techniques vs. 4/28 (14%) of spontaneous multiple pregnancies (p = 0.22). 21/134 (16%) of the products conceived by assisted reproduction techniques and 6/88 (7%) of spontaneous (p assisted reproduction and 21% of the cases had one or more fatal events (11% more in pregnancies achieved by assisted reproduction techniques). 12% of the products of multiple pregnancies died (9% more in those obtained by a technique of assisted reproduction).

Yeast Population Dynamics in Spontaneous and Inoculated Alcoholic Fermentations of Zametovka Must

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Franc Cus

2002-01-01

Full Text Available Inoculated fermentations, which are more rapid and more reliable than spontaneous fermentations, and assure predictable wine quality, are nowadays prevalent in Slovenia’s large-scale wine production. However, spontaneous fermentation strengthens local characteristics of wine and offers opportunities for technological innovation. In the 1999 vintage, spontaneous and inoculated fermentations of Zametovka (Vitis vinifera grape must were studied. Zametovka is the main red variety in production of traditional Slovene red blend wine, Cvicek. The diversity of yeast species and strains in both of the investigated fermentations was determined by molecular and traditional identification methods. The outset of alcoholic fermentation, yeast growth kinetics, and yeast population dynamics presents the main differences between the examined fermentations. Yeast population diversity was higher in the spontaneous process. Dominant yeast isolates from spontaneous fermentation were identified as Candida stellata, Hanseniaspora uvarum and Saccharomyces cerevisiae; whereas Saccharomyces bayanus, Pichia kluyveri, Pichia membranifaciens and Torulaspora delbrueckiim were found less frequently. Dominant species in the inoculated fermentation was Saccharomyces cerevisiae; other species found in smaller numbers were Candida stellata, Hanseniaspora uvarum and Debaryomyces hansenii var. hansenii. Using PFGE, we were able to distinguish among 15 different Saccharomyces cerevisiae strains and three different Saccharomyces bayanus strains isolated from spontaneous fermentation, whereas, in the case of inoculated fermentation, only two Saccharomyces cerevisiae strains were found. Their chromosomal patterns coincide with the chromosomal patterns of the starter culture strains.

On spontaneous parity breaking in three-dimensional gauge-Higgs systems

International Nuclear Information System (INIS)

Ambjoern, J.; Farakos, K.; Shaposhnikov, M.E.

1991-04-01

We address the question of spontaneous breaking of parity in three-dimensional euclidian SU(2) gauge-Higgs theory by Monte Carlo simulations. We observe no sign of spontaneous parity breaking in the behaviour of local gauge invariant operators. However, the presence of parity odd terms in the action can induce a phase transition to a parity odd ground state. (orig.)

Tamsulosin modulates, but does not abolish the spontaneous activity in the guinea pig prostate gland.

Science.gov (United States)

Chakrabarty, Basu; Dey, Anupa; Lam, Michelle; Ventura, Sabatino; Exintaris, Betty

2015-06-01

To examine the effects of the α1A -adrenoceptor antagonist, tamsulosin, on spontaneous contractile and electrical activity in the guinea-pig prostate gland. The effects of tamsulosin (0.1 and 0.3 nM) were investigated in adult and ageing male guinea pig prostate glands using conventional tension recording and electrophysiological intracellular microelectrode recording techniques. Tamsulosin reduced spontaneous activity, and had different age-dependent effects on adult and ageing guinea pigs at different concentrations. 0.1 nM tamsulosin caused a significantly greater reduction of spontaneous contractile and electrical activity in ageing guinea pigs in comparison to adult guinea pigs. In contrast, 0.3 nM tamsulosin had a significantly greater reduction of spontaneous contractile and electrical activity in adult guinea pigs in comparison to ageing guinea pigs. This study demonstrates that tamsulosin can modulate spontaneous myogenic stromal contractility and the underlying spontaneous electrical activity; tamsulosin does not block spontaneous activity. This reduction in spontaneous activity suggests that downstream cellular mechanisms underlying smooth muscle tone are being targeted, and these may represent novel therapeutic targets to better treat benign prostatic hyperplasia. © 2014 Wiley Periodicals, Inc.

Polarization control of spontaneous emission for rapid quantum-state initialization

Science.gov (United States)

DiLoreto, C. S.; Rangan, C.

2017-04-01

We propose an efficient method to selectively enhance the spontaneous emission rate of a quantum system by changing the polarization of an incident control field, and exploiting the polarization dependence of the system's spontaneous emission rate. This differs from the usual Purcell enhancement of spontaneous emission rates as it can be selectively turned on and off. Using a three-level Λ system in a quantum dot placed in between two silver nanoparticles and a linearly polarized, monochromatic driving field, we present a protocol for rapid quantum state initialization, while maintaining long coherence times for control operations. This process increases the overall amount of time that a quantum system can be effectively utilized for quantum operations, and presents a key advance in quantum computing.

Spontaneous regression of a cervical intraspinal cyst in a dog

International Nuclear Information System (INIS)

Kamishina, Hiroaki; Katayama, Masaaki; Yasuda, Jun; Sato, Reeko; Ogawa, Hiroya; Tohyama, Koujiro

2010-01-01

We report a cervical intraspinal cyst in a dog that was initially tetraparetic but spontaneously recovered completely. MRI revealed a well-demarcated intraspinal cyst located dorsally to a degenerated intervertebral disc. The location of the cyst and its signal features on MRI resembled those of discal cysts previously reported in humans. It has been reported in dogs that clinical signs of a intraspinal cyst are similar to those of intervertebral disc herniation and both conditions require surgical intervention. Unexpectedly, our case showed rapid spontaneous recovery and the follow-up MRI revealed complete resolution of the intraspinal cyst and spinal cord compression. Spontaneous recovery of degenerative intraspinal cyst may occur in dogs, similar to rare human cases as reported previously. (author)

Spontaneous symmetry breaking in 4-dimensional heterotic string

International Nuclear Information System (INIS)

Maharana, J.

1989-07-01

The evolution of a 4-dimensional heterotic string is considered in the background of its massless excitations such as graviton, antisymmetric tensor, gauge fields and scalar bosons. The compactified bosonic coordinates are fermionized. The world-sheet supersymmetry requirement enforces Thirring-like four fermion coupling to the background scalar fields. The non-abelian gauge symmetry is exhibited through the Ward identities of the S-matrix elements. The spontaneous symmetry breaking mechanism is exhibited through the broken Ward identities. An effective 4-dimensional action is constructed and the consequence of spontaneous symmetry breaking is envisaged for the effective action. 19 refs

Frequency of microbial spectrum of spontaneous bacterial peritonitis in established cirrhosis liver

International Nuclear Information System (INIS)

Zaman, A.; Kareem, R.; Khan, E.M.

2011-01-01

Background: Spontaneous bacterial peritonitis is one of the most frequent and serious complication in patients with liver cirrhosis and ascites associated with high mortality. Empiric antibiotic therapy should be initiated before the results of ascitic fluid cultures are available, guided by knowledge of the microbial spectrum of spontaneous bacterial peritonitis in a particular population. Methods: This is a descriptive study which was carried out in the Department of Gastroenterology and Hepatology, Postgraduate Medical Institute Hayatabad Medical Complex, Peshawar from January 2007 to December 2007. Fifty consecutive patients of established cirrhosis liver with ascites presenting with suspicion and or risk factors for spontaneous bacterial peritonitis were included in the study after informed consent. All selected patients were subjected to ascitic fluid tap. Twenty ml of ascitic fluid was aspirated in a heparinised disposable syringe; out of it 10 ml was immediately inoculated into blood culture bottle at bedside and sent for bacterial culture along with the remaining 10 ml for routine biochemical and cytological examination. Results: Out of 50 patients, 28 (56%) were diagnosed to have spontaneous bacterial peritonitis or its variants. Classic spontaneous bacterial peritonitis was present in 11 patients (39.28%), 16 (57.14%) patients were found to have culture negative neutrocytic ascites and one patient (3.57%) had bacterascites. Out of 28 cases of spontaneous bacterial peritonitis 12 samples of ascitic fluid showed positive culture reports. E. coli was the most frequently cultured organism isolated in 8 (66.66%) cases, Streptococcus pneumonae in 2 patients (16.66%), Staphylococcus aurus and Klebsiella each in 1 case (8.33%). Conclusion: Spontaneous bacterial peritonitis and its variants is a common complication of liver cirrhosis with ascites. E. coli is the most frequent offending organism in these cases. Knowledge of the microbial spectrum of spontaneous

Proteomic Biomarkers for Spontaneous Preterm Birth

DEFF Research Database (Denmark)

Kacerovsky, Marian; Lenco, Juraj; Musilova, Ivana

2014-01-01

This review aimed to identify, synthesize, and analyze the findings of studies on proteomic biomarkers for spontaneous preterm birth (PTB). Three electronic databases (Medline, Embase, and Scopus) were searched for studies in any language reporting the use of proteomic biomarkers for PTB published...

Structure of the vitreoretinal border region in spontaneously hypertensive rats (SHR rats)

DEFF Research Database (Denmark)

Heegaard, Steffen

1993-01-01

Øjenpatologi, vitreoretinal border region, inner limiting membrane of the retina, spontaneously hypertensive rats, SHR rats, ultrastructure......Øjenpatologi, vitreoretinal border region, inner limiting membrane of the retina, spontaneously hypertensive rats, SHR rats, ultrastructure...

Role of spontaneous and stimulated emission in photon correlations

International Nuclear Information System (INIS)

Chopra, S.; Bohidar, H.; Harwalkar, V.

1984-01-01

Photon correlations have been alternately attributed to either spontaneous or stimulated emission by various authors. In this paper, the authors interpret, on the basis of available experimental data, the contribution of each emission form to the evolution of photon statistics. The laser is used as an example of a source which exhibits different statistical characteristics depending on the level of excitation, which is governed by the pump parameter a. From the data, it is evident that the transition from below to above threshold is accompanied by a significant drop in the magnitude of correlation and an increase in decay time. It may be noted that this transition causes a substantial increase in the coherent output which emphasizes the predominance of stimulated emission. In the case of a laser below threshold, however, photon correlations arise due to superposition of the more dominant spontaneously emitted wavetrains. Exact solutions of quantized systems do not exist in the presence of saturation effects. This implies that factorization and identification of terms with spontaneous or stimulated emission has not yet been done. This does not preculde a physical and intuitive interpretation of photon statistics within the framework of a standard model, and it is therefore argued that spontaneous emission is responsible for photon correlations while stimulated emission shows up in the dynamics as the coherence time

Absolute calibration technique for spontaneous fission sources

International Nuclear Information System (INIS)

Zucker, M.S.; Karpf, E.

1984-01-01

An absolute calibration technique for a spontaneously fissioning nuclide (which involves no arbitrary parameters) allows unique determination of the detector efficiency for that nuclide, hence of the fission source strength

Spontaneous spinal epidural abscess.

LENUS (Irish Health Repository)

Ellanti, P

2011-10-01

Spinal epidural abscess is an uncommon entity, the frequency of which is increasing. They occur spontaneously or as a complication of intervention. The classical triad of fever, back pain and neurological symptoms are not always present. High index of suspicion is key to diagnosis. Any delay in diagnosis and treatment can have significant neurological consequences. We present the case of a previously well man with a one month history of back pain resulting from an epidural abscess.

Prospective controlled trial comparing colostomy irrigation with "spontaneous-action" method.

Science.gov (United States)

Williams, N S; Johnston, D

1980-07-12

Thirty randomly selected patients with permanent colostomies entered a prospective controlled trial comparing colostomy irrigation with spontaneous action. Each patient was interviewed and examined before irrigation was begun and again after the technique had been used for three months. Each then reverted to spontaneous action for a further three months and was then reassessed. Eight patients abandoned irrigation and 22 (73%) adhered to the protocol. Irrigation caused no mishaps or complications. The mean time spent managing the stoma was 45 +/- SEM 9 min/24 hours during spontaneous action and 53 +/- 9 min/24 hours during irrigation. This difference was not significant. The numbers of bowel actions weekly were 13 +/ SEM 2 during spontaneous action and 6 +/- 1 during irrigation (p Irrigation reduced odour and flatus in 20 patients and enabled 12 out of 18 to stop using drugs and seven to discard their appliance. Irrigation also improved the social life of 18 patients and the working conditions of eight out of 14. These finding show that some patients may not be suitable for irrigation but that for many it is better than the conventional British method of colostomy management. With modern apparatus the technique is safe.

Intake of probiotic food and risk of spontaneous preterm delivery.

Science.gov (United States)

Myhre, Ronny; Brantsæter, Anne Lise; Myking, Solveig; Gjessing, Håkon Kristian; Sengpiel, Verena; Meltzer, Helle Margrete; Haugen, Margaretha; Jacobsson, Bo

2011-01-01

Preterm delivery represents a substantial problem in perinatal medicine worldwide. Current knowledge on potential influences of probiotics in food on pregnancy complications caused by microbes is limited. We hypothesized that intake of food with probiotics might reduce pregnancy complications caused by pathogenic microorganisms and, through this, reduce the risk of spontaneous preterm delivery. This study was performed in the Norwegian Mother and Child Cohort on the basis of answers to a food-frequency questionnaire. We studied intake of milk-based products containing probiotic lactobacilli and spontaneous preterm delivery by using a prospective cohort study design (n = 950 cases and 17,938 controls) for the pregnancy outcome of spontaneous preterm delivery (delivery were associated with any intake of milk-based probiotic products in an adjusted model [odds ratio (OR): 0.857; 95% CI: 0.741, 0.992]. By categorizing intake into none, low, and high intakes of the milk-based probiotic products, a significant association was observed for high intake (OR: 0.820; 95% CI: 0.681, 0.986). Women who reported habitual intake of probiotic dairy products had a reduced risk of spontaneous preterm delivery.

Sustainability Reporting and Value Relevance of Financial Statements

Directory of Open Access Journals (Sweden)

Bambang Sutopo

2018-03-01

Full Text Available This study examines whether information about the winners of the Sustainability Reporting Award (SRA contributes to the usefulness of the information in financial statements. This study used a sample consisting of 110 winners of SRA (SRA firms and 110 companies that did not receive SRA (non-SRA firms from 2008 to 2016. The study found that earnings per share (EPS, earnings per share change (EPSC, and book value per share (BVPS are value-relevant information. Results of comparison between SRA firms and non-SRA firms show that the positive association between EPS and stock price (P and the positive association of EPS with stock returns (R for SRA firms are higher than that for the non-SRA firms. In addition, findings of this study indicate that EPSC is positively associated with R when EPSC and R are measured by Indonesian rupiah (IDR instead of by percentage, and the positive association between EPSC and R for the SRA firms is higher than that for the non-SRA firms. Thus, the results are sensitive to measures of the variables. However, this study found that value relevance of BVPS for SRA firms is lower than for non-SRA firms. Implication of this study is that information about the winners of SRA contributes to the usefulness of financial statements, especially the information of EPS and EPSC.

Transformation quantum optics: designing spontaneous emission using coordinate transformations

DEFF Research Database (Denmark)

Zhang, Jingjing; Wubs, Martijn; Ginzburg, Pavel

2016-01-01

Spontaneous decay is a fundamental quantum property of emitters that can be controlled in a material environment via modification of the local density of optical states (LDOS). Here we use transformation optics methods in order to design required density of states and thus spontaneous emission (S......, affect the LDOS in complex materials. Tailoring SE properties using transformation optics approach provides an innovative way for designing emission properties in a complex material environment needed for the development of active nanophotonic devices....

Gauge theories as theories of spontaneous breakdown

International Nuclear Information System (INIS)

Ivanov, E.A.; Ogievetsky, V.I.

1976-01-01

Any gauge theory is proved to arise from spontaneous breakdown of symmetry under certain infinite parameter group, the corresponding gauge field being the Goldstone field by which this breakdown is accompanied

Spontaneous fluxoid formation in superconducting loops

DEFF Research Database (Denmark)

Monaco, R.; Mygind, Jesper; Rivers, R.

2009-01-01

We report on the experimental verification of the Zurek-Kibble scenario in an isolated superconducting ring over a wide parameter range. The probability of creating a single flux quantum spontaneously during the fast normal-superconducting phase transition of a wide Nb loop clearly follows...

Spontaneous emission from active dielectric microstructures

DEFF Research Database (Denmark)

Søndergaard, Thomas; Tromborg, Bjarne

2001-01-01

and engineered due to the dependence of the emission rate on the location and polarisation of the emitters in the structure. This paper addresses the methods of quantum electrodynamics of dielectric media which enable calculation of the local rate of spontaneous emission in active microstructures....

SELECTING PARAMETERS OF PREPARATION SOURDOUGH SPONTANEOUS FERMENTATION OF WHEAT BIOACTIVATED

Directory of Open Access Journals (Sweden)

E. I. Ponomareva

2013-01-01

Full Text Available One way to improving the quality of semi-finished and finished bakery products is the use of starter cultures. This article describes a process for preparing sourdough bioactivated spontaneous fermentation of wheat. The influence of parameters of spontaneous sourdough cooking at its organoleptic, physico-chemical and microbiological parameters was studying, rational parameters of receipt that improve the quality of foods were chosen.

Spontaneous splenic rupture in Waldenstrom's macroglobulinemia: a case report

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Charakidis Michail

2010-09-01

Full Text Available Abstract Introduction We report the case of a patient with Waldenstrom's macroglobulinemia complicated by spontaneous splenic rupture. Case presentation A 49-year-old Caucasian woman was referred to our emergency department by her general practitioner following a three-week history of malaise, night sweats, six kilograms of weight loss, intermittent nausea and vomiting, progressive upper abdominal pain and easy bruising. On the fourth day following her admission, she had a rapid clinical deterioration, with subsequent radiological investigations revealing a splenic rupture. Her morphology, biochemistry, flow cytometry and histology were strongly suggestive of Waldenstrom's macroglobulinemia. Conclusions Spontaneous splenic rupture is not an expected complication of low-grade lymphoplasmacytic lymphomas, such as Waldenstrom's macroglobulinemia. To the best of our knowledge, this is the only reported case of early spontaneous splenic rupture due to Waldenstrom's macroglobulinemia. Our case highlights that despite the typical disease course of low-grade hematological malignancies, signs and symptoms of imminent splenic rupture should be considered when formulating a clinical assessment.

Spontaneous aorto-cisterna chyli anastomosis

International Nuclear Information System (INIS)

Vlahos, L.; Gouliamos, A.; Nikolaidis, I.; Dimakakos, P.

1986-01-01

A case of a spontaneous aorto-cisterna chyli communication is presented in a 65 year old patient who was admitted to the Hospital with severe abdominal pain simulating a dissecting aneurysm of the aorta. The diagnosis was suspected on a CT examination and established by a free flow aortogram and selective catheterization of the cisterna chyli through the aorta. (orig.)

Spontaneous aorto-cisterna chyli anastomosis

Energy Technology Data Exchange (ETDEWEB)

Vlahos, L.; Gouliamos, A.; Nikolaidis, I.; Dimakakos, P.

1986-02-01

A case of a spontaneous aorto-cisterna chyli communication is presented in a 65 year old patient who was admitted to the Hospital with severe abdominal pain simulating a dissecting aneurysm of the aorta. The diagnosis was suspected on a CT examination and established by a free flow aortogram and selective catheterization of the cisterna chyli through the aorta. (orig.).

Right Diaphragm Spontaneous Rupture: A Surgical Approach

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Duilio Divisi

2011-01-01

Full Text Available We present a case of spontaneous rupture of the diaphragm, characterized by nonspecific symptoms. The rapid diagnosis and appropriate surgical approach led to a positive resolution of the pathology.

Spontaneous pneumomediastinum on CT : related condition and its clinical significance

International Nuclear Information System (INIS)

Kim, Sung Hyun; Im, Jung Gi; Seo, Joon Beom; Park, Jae Hyung; Yeon, Kyung Mo; Han, Man Chung

1998-01-01

The purpose of this paper is to tabulate underlying disease and to assess the clinical significance of CT-diagnosed spontaneous pneumomediastinum. We retrospectively reviewed CT scans and medical records of 11 consecutive patients with spontaneous pneumomediastinum, and analyzed their clinical history and course, and in five cases, pulmonary function. CT scans of 126 patients with idiopathic pulmonary fibrosis (IPE) collected while the 11 consecutive patients were being treated were analyzed for the prevalence of pneumomediastinum. We analyzed CT findings with respect to the amount and distribution of air in the mediastinum, and the presence of absence of air outside the mediastinum. Spontaneous pneumomediastinum might be associated with idiopathic pulmonary fibrosis and might be a poor prognostic factor in patients with IPE or BOOP. (author). 18 refs., 2 figs

Spontaneous pneumomediastinum on CT : related condition and its clinical significance

Energy Technology Data Exchange (ETDEWEB)

Kim, Sung Hyun; Im, Jung Gi; Seo, Joon Beom; Park, Jae Hyung; Yeon, Kyung Mo; Han, Man Chung [Seoul National Univ. (Korea, Republic of). Coll. of Medicine

1998-03-01

The purpose of this paper is to tabulate underlying disease and to assess the clinical significance of CT-diagnosed spontaneous pneumomediastinum. We retrospectively reviewed CT scans and medical records of 11 consecutive patients with spontaneous pneumomediastinum, and analyzed their clinical history and course, and in five cases, pulmonary function. CT scans of 126 patients with idiopathic pulmonary fibrosis (IPE) collected while the 11 consecutive patients were being treated were analyzed for the prevalence of pneumomediastinum. We analyzed CT findings with respect to the amount and distribution of air in the mediastinum, and the presence of absence of air outside the mediastinum. Spontaneous pneumomediastinum might be associated with idiopathic pulmonary fibrosis and might be a poor prognostic factor in patients with IPE or BOOP. (author). 18 refs., 2 figs.

Spontaneous pushing to prevent postpartum urinary incontinence: a randomized, controlled trial.

Science.gov (United States)

Low, Lisa Kane; Miller, Janis M; Guo, Ying; Ashton-Miller, James A; DeLancey, John O L; Sampselle, Carolyn M

2013-03-01

The risk for urinary incontinence can be 2.6-fold greater in women after pregnancy and childbirth compared with their never-pregnant counterparts, with the incidence increasing with parity. We tested the hypothesis that the incidence of de novo postpartum urinary incontinence in primiparous women is reduced with the use of spontaneous pushing alone or in combination with perineal massage compared with women who experienced traditional directed pushing for second-stage management. This was a prospective clinical trial enrolling and randomizing 249 women into a four-group design: (1) routine care with coached or directed pushing, (2) spontaneous self-directed pushing, (3) prenatal perineal massage initiated in the third trimester, and (4) the combination of spontaneous pushing plus perineal massage. Self-report of incontinence was assessed using analysis of variance (ANOVA) and covariance (ANCOVA) models in 145 remaining women at 12 months postpartum using the Leakage Index, which is sensitive to minor leakage. No statistical difference in the incidence of de novo postpartum incontinence was found based on method of pushing (spontaneous/directed) (P value = 0.57) or in combination with prenatal perineal massage (P value = 0.57). Fidelity to pushing treatment of type was assessed and between-groups crossover detected. Spontaneous pushing did not reduce the incidence of postpartum incontinence experienced by women 1 year after their first birth due to high cross-over between randomization groups.

[Mechanisms of endogenous drug resistance acquisition by spontaneous chromosomal gene mutation].

Science.gov (United States)

Fukuda, H; Hiramatsu, K

1997-05-01

Endogenous resistance in bacteria is caused by a change or loss of function and generally genetically recessive. However, this type of resistance acquisition are now prevalent in clinical setting. Chromosomal genes that afford endogenous resistance are the genes correlated with the target of the drug, the drug inactivating enzymes, and permeability of the molecules including the antibacterial agents. Endogenous alteration of the drug target are mediated by the spontaneous mutation of their structural gene. This mutation provides much lower affinity of the drugs for the target. Gene expression of the inactivating enzymes, such as class C beta-lactamase, is generally regulated by regulatory genes. Spontaneous mutations in the regulatory genes cause constitutive enzyme production and provides the resistant to the agent which is usually stable for such enzymes. Spontaneous mutation in the structural gene gives the enzyme extra-spectrum substrate specificity, like ESBL (Extra-Spectrum-beta-Lactamase). Expression of structural genes encoding the permeability systems are also regulated by some regulatory genes. The spontaneous mutation of the regulatory genes reduce an amount of porin protein. This mutation causes much lower influx of the drug in the cell. Spontaneous mutation in promoter region of the structural gene of efflux protein was observed. This mutation raised the gene transcription and overproduced efflux protein. This protein progresses the drug efflux from the cell.

Gene expression profiling distinguishes between spontaneous and radiation-induced rat mammary carcinomas

International Nuclear Information System (INIS)

Imaoka, Tatsuhiko; Nishimura, Mayumi; Kakinuma, Shizuko; Shimada, Yoshiya; Yamashita, Satoshi; Ushijima, Toshikazu

2008-01-01

The ability to distinguish between spontaneous and radiation-induced cancers in humans is expected to improve the resolution of estimated risk from low dose radiation. Mammary carcinomas were obtained from Sprague-Dawley rats that were either untreated (n=45) or acutely γ-irradiated (1 Gy; n=20) at seven weeks of age. Gene expression profiles of three spontaneous and four radiation-induced carcinomas, as well as those of normal mammary glands, were analyzed by microarrays. Differential expression of identified genes of interest was then verified by quantitative polymerase chain reaction (qPCR). Cluster analysis of global gene expression suggested that spontaneous carcinomas were distinguished from a heterogeneous population of radiation-induced carcinomas, though most gene expressions were common. We identified 50 genes that had different expression levels between spontaneous and radiogenic carcinomas. We then selected 18 genes for confirmation of the microarray data by qPCR analysis and obtained the following results: high expression of Plg, Pgr and Wnt4 was characteristic to all spontaneous carcinomas; Tnfsf11, Fgf10, Agtr1a, S100A9 and Pou3f3 showed high expression in a subset of radiation-induced carcinomas; and increased Gp2, Areg and Igf2 expression, as well as decreased expression of Ca3 and noncoding RNA Mg1, were common to all carcinomas. Thus, gene expression analysis distinguished between spontaneous and radiogenic carcinomas, suggesting possible differences in their carcinogenic mechanism. (author)

Dimensionless model to determine spontaneous combustion danger zone in the longwall gob

Institute of Scientific and Technical Information of China (English)

ZHANG Xin-hai; DENG Jun; WEN Hu

2011-01-01

According to spontaneous combustion propensity,the longwall gob is divided into three zones,including heat dissipation zone,self-heating zone and the choking zone.Only in the self-heating zone can temperature of coal rise due to oxidation.Studying the distribution of the “Three Zones” in gob is important for predicting and preventing spontaneous combustion in coalmine.In normal mining operations,temperature of coal is roughly constant.The process of mass transfer in the gob is considered to be steady.Based on mass conservation,gas species conservation,darcy' s law,Ficks law of diffusion and coal oxidation 1-grade reaction rule,governing equation for air leakage intensity and species concentration are deduced.With critical value of coal spontaneous combustion and the size of longwall workface as basic dimension,a dimensionless steady coupled model of air flow diffusion and chemical reaction in loose coal of Fully Mechanized Top-Coal Caving Mining Workface (FMTCCMW) is setup.By solving the model numerically,regulation of three zones' distribution and spontaneous combustion in the gob can be obtained.The results can be easily popularized to prediction of spontaneous combustion in other coalmines' longwall gob.

Thirty-day readmission after spontaneous intracerebral hemorrhage.

Science.gov (United States)

Bjerkreim, Anna Therese; Khanevski, Andrej Netland; Glad, Solveig Bergliot; Thomassen, Lars; Naess, Halvor; Logallo, Nicola

2018-03-01

Intracerebral hemorrhage (ICH) is the most severe form of stroke, but data on readmission after ICH are sparse. We aimed to determine frequency, causes, and predictors of 30-day readmission after ICH. This retrospective cohort study includes all spontaneous ICH survivors admitted to the stroke unit at Haukeland University Hospital in Bergen in Norway from July 2007 to December 2013. Patients were followed by review of electronic medical charts, and the first unplanned readmission within 30 days after discharge was used as final outcome. Cox regression analysis was performed to identify predictors of 30-day readmission. We identified 226 patients with spontaneous ICH, 70 (31.0%) of whom died before discharge or were discharged to palliative care. Of the remaining 156 ICH survivors, 28 (18.0%) were readmitted within 30 days. Median time to readmission was 12 days (IQR 4.5 - 18.5). Most patients were readmitted due to infections ( N  = 13). None of the patients were readmitted with recurrent stroke. Pneumonia and enteral feeding during the index hospitalization were associated with readmission for infections (both p  readmission (HR 1.06, 95% CI 1.02 - 1.11, p  =   .006). Almost one in five of our spontaneous ICH survivors was readmitted within 30 days, and most readmissions were caused by infections.

Hepatic Rupture Induced by Spontaneous Intrahepatic Hematoma

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Jin-bao Zhou

2018-01-01

Full Text Available The etiology of hepatic rupture is usually secondary to trauma, and hepatic rupture induced by spontaneous intrahepatic hematoma is clinically rare. We describe here a 61-year-old female patient who was transferred to our hospital with hepatic rupture induced by spontaneous intrahepatic hematoma. The patient had no history of trauma and had a history of systemic lupus erythematosus for five years, taking a daily dose of 5 mg prednisone for treatment. The patients experienced durative blunt acute right upper abdominal pain one day after satiation, which aggravated in two hours, accompanied by dizziness and sweating. Preoperative diagnosis was rupture of the liver mass. Laparotomy revealed 2500 mL fluid consisting of a mixture of blood and clot in the peritoneal cavity. A 3.5 cm × 2.5 cm rupture was discovered on the hepatic caudate lobe near the vena cava with active arterial bleeding, and a 5  × 6 cm hematoma was reached on the right posterior lobe of the liver. Abdominal computed tomography (CT and laparotomy revealed spontaneous rupture of intrahepatic hematoma with hemorrhagic shock. The patient was successfully managed by suturing the rupture of the hepatic caudate lobe and clearing part of the hematoma. The postoperative course was uneventful, and the patient was discharged after two weeks of hospitalization.

Spontaneous mutation rate in Chinese hamster cell clones differing in UV-sensitivity

International Nuclear Information System (INIS)

Manuilova, E.S.; Bagrova, A.M.; Moskovskij Gosudarstvennyj Univ.

1983-01-01

The spontaneous rate of appearance of mutations to 6-mercaptopurine (6 MP) resistence in the cells of CHR2 and CHs2 clones dofferent in sensitivity to lethal and matagenous effect of UV-rays, is investigated. Increased UV-sensitivity of CHs2 clone is caused by the violation of postreplicative DNA reparation. It is established that the purity of spontaneously occuring mutations in both clones turns out to be similar, i.e. (1.5-1.8)x10 -5 for the cell pergeneration. It is shown that the effect of postreplicative DNA reparation in the cells of chinese hamster is not connected with the increase of spontaneous mutation ability. The problem on the possible role of reparation in the mechanism of appearance of spontaneous and induced mutations in the cells of Chinese hamster with increased UV-sensitivity is discussed

Spontaneous Symmetry Breaking and Nambu–Goldstone Bosons in Quantum Many-Body Systems

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Tomáš Brauner

2010-04-01

Full Text Available Spontaneous symmetry breaking is a general principle that constitutes the underlying concept of a vast number of physical phenomena ranging from ferromagnetism and superconductivity in condensed matter physics to the Higgs mechanism in the standard model of elementary particles. I focus on manifestations of spontaneously broken symmetries in systems that are not Lorentz invariant, which include both nonrelativistic systems as well as relativistic systems at nonzero density, providing a self-contained review of the properties of spontaneously broken symmetries specific to such theories. Topics covered include: (i Introduction to the mathematics of spontaneous symmetry breaking and the Goldstone theorem. (ii Minimization of Higgs-type potentials for higher-dimensional representations. (iii Counting rules for Nambu–Goldstone bosons and their dispersion relations. (iv Construction of effective Lagrangians. Specific examples in both relativistic and nonrelativistic physics are worked out in detail.

Spontaneous pneumorrhachis and transverse myelitis complicating purulent meningitis

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Bouchra Amara

2013-01-01

Full Text Available Pneumorrhachis is the presence of air in the spinal canal; mostly, it has an iatrogenic origin. The association of this entity with spontaneous pneumomediastinum without any pneumothorax is rarely reported in the literature. The spontaneous resorption is the usual evolution. The association to acute transverse myelitis is discussed by the authors. The patient is a 21-year-old male with pneumorrhachis associated to a spontaneous pneumomediastinum was admitted at the emergency department for bacterial meningitis. The antibiotherapy has marked the clinical profile by disappearance of the meningeal signs in the 48 h after admission. In contrast, the neurological symptoms were of marked aggravation by appearance of a tetraparesis with a respiratory distress syndrome having required artificial ventilation. The computed tomography (CT scan showed a typical hypodensity corresponding to paramedullary air extending to several thoracic segments. The spinal magnetic resonance imaging (MRI showed a high cervical medullary edema without signs of compression. The patient died within 15 days with a profile of vasoparalysis resistant to vasoactive drugs. Pneumomediastinum associated to pneumorrhachis and transverse myelitis complicating purulent meningitis is a rare entity. Although the usual evolution is favorable, the occurrence of serious complications is possible.

Mechanisms of morphine enhancement of spontaneous seizure activity.

Science.gov (United States)

Saboory, Ehsan; Derchansky, Miron; Ismaili, Mohammed; Jahromi, Shokrollah S; Brull, Richard; Carlen, Peter L; El Beheiry, Hossam

2007-12-01

High-dose opioid therapy can precipitate seizures; however, the mechanism of such a dangerous adverse effect remains poorly understood. The aim of our study was to determine whether the neuroexcitatory activity of high-dose morphine is mediated by selective stimulation of opioid receptors. Mice hippocampi were resected intact and bathed in low magnesium artificial cerebrospinal fluid to induce spontaneous seizure-like events recorded from CA1 neurons. Application of morphine had a biphasic effect on the recorded spontaneous seizure-like events. In a low concentration (10 microM), morphine depressed electrographic seizure activity. Higher morphine concentrations (30 and 100 microM) enhanced seizure activity in an apparent dose-dependent manner. Naloxone, a nonselective opiate antagonist blocked the proconvulsant action of morphine. Selective mu and kappa opiate receptor agonists and antagonists enhanced and suppressed the spontaneous seizure activity, respectively. On the contrary, delta opioid receptor ligands did not have an effect. The proseizure effect of morphine is mediated through selective stimulation of mu and kappa opiate receptors but not the activation of the delta receptor system. The observed dose-dependent mechanism of morphine neuroexcitation underscores careful adjustment and individualized opioid dosing in the clinical setting.

Chronic Allium sativum administration alters spontaneous ...

African Journals Online (AJOL)

The whole brains were removed and the medial prefrontal cortex excised and processed for histomorphologic studies by haematoxylin and eosin, and cresyl fast violet techniques. Neurobehavioural test revealed less spontaneous alternation in 156 mg/kg Allium sativum group, while the prefrontal cortices of the test groups ...

Motivational Projections of Russian Spontaneous Speech

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Galina M. Shipitsina

2017-06-01

Full Text Available The article deals with the semantic, pragmatic and structural features of words, phrases, dialogues motivation, in the contemporary Russian popular speech. These structural features are characterized by originality and unconventional use. Language material is the result of authors` direct observation of spontaneous verbal communication between people of different social and age groups. The words and remarks were analyzed in compliance with the communication system of national Russian language and cultural background of popular speech. Studies have discovered that in spoken discourse there are some other ways to increase the expression statement. It is important to note that spontaneous speech identifies lacunae in the nominative language and its vocabulary system. It is proved, prefixation is also effective and regular way of the same action presenting. The most typical forms, ways and means to update language resources as a result of the linguistic creativity of native speakers were identified.

Spontaneous bending of pre-stretched bilayers.

Science.gov (United States)

DeSimone, Antonio

2018-01-01

We discuss spontaneously bent configurations of pre-stretched bilayer sheets that can be obtained by tuning the pre-stretches in the two layers. The two-dimensional nonlinear plate model we use for this purpose is an adaptation of the one recently obtained for thin sheets of nematic elastomers, by means of a rigorous dimensional reduction argument based on the theory of Gamma-convergence (Agostiniani and DeSimone in Meccanica. doi:10.1007/s11012-017-0630-4, 2017, Math Mech Solids. doi:10.1177/1081286517699991, arXiv:1509.07003, 2017). We argue that pre-stretched bilayer sheets provide us with an interesting model system to study shape programming and morphing of surfaces in other, more complex systems, where spontaneous deformations are induced by swelling due to the absorption of a liquid, phase transformations, thermal or electro-magnetic stimuli. These include bio-mimetic structures inspired by biological systems from both the plant and the animal kingdoms.

Intrasphenoidal encephalocele and spontaneous CSF rhinorrhoea.

Science.gov (United States)

Daniilidis, J; Vlachtsis, K; Ferekidis, E; Dimitriadis, A

1999-12-01

Intrasphenoidal encephalocele is a rare clinical entity. In the international literature only 16 cases have been reported up today, with female predominance. Clinically they manifest at middle and advanced ages (40-67 years), when spontaneous CSF rhinorrhoea or recurrent meningitis occurs. We present our case, a 46 years old female, who had CSF rhinorrhoea from the right vestibule for 10 months. The diagnosis was based on the history and the high-resolution brain and skull base CT-scanning in conjunction with opaque fluid injection in the subarachnoidal space through a lumbar puncture. She was successfully treated with an operation, through an endonasal trans-ethmoid microendoscopic approach, using the Draf and Stammberger technique. We discuss the pathogenesis of the intrasphenoidal encephalocele, the existence of small occult defects in the skull base, which cause, at the middle and advanced ages, CSF fistula with spontaneous CSF rhinorrhoea and/or recurrent meningitis. Finally we emphasize the advantages of the endonasal surgical approach for the treatment of this condition.

Spontaneous actin dynamics in contractile rings

Science.gov (United States)

Kruse, Karsten; Wollrab, Viktoria; Thiagarajan, Raghavan; Wald, Anne; Riveline, Daniel

Networks of polymerizing actin filaments are known to be capable to self-organize into a variety of structures. For example, spontaneous actin polymerization waves have been observed in living cells in a number of circumstances, notably, in crawling neutrophils and slime molds. During later stages of cell division, they can also spontaneously form a contractile ring that will eventually cleave the cell into two daughter cells. We present a framework for describing networks of polymerizing actin filaments, where assembly is regulated by various proteins. It can also include the effects of molecular motors. We show that the molecular processes driven by these proteins can generate various structures that have been observed in contractile rings of fission yeast and mammalian cells. We discuss a possible functional role of each of these patterns. The work was supported by Agence Nationale de la Recherche, France, (ANR-10-LABX-0030-INRT) and by Deutsche Forschungsgemeinschaft through SFB1027.

Multiple spontaneous bone infarcts secondary to alcohol abuse

International Nuclear Information System (INIS)

Wadhwa, S.S.; Mansberg, R.

1999-01-01

Alcohol induced spontaneous osteonecrosis is part of the differential diagnosis in patients with history of alcohol abuse and diffuse bone pain. Usually patients have a longer than 10 year history of alcohol abuse prior to the development of osteonecrosis. The femoral head is the commonest site involved, however, involvement of the long bones is also seen. Facial involvement is rarely seen. Fat embolism secondary to coexisting hyperlipidemia has been postulated as a possible cause of osteonecrosis in alcoholics. A case of multifocal spontaneous bone infarction with facial bone involvement in a 34 year old female alcoholic is described. Copyright (1999) The Australian and New Zealand Society of Nuclear Medicine Inc

Prospective controlled trial comparing colostomy irrigation with "spontaneous-action" method.

OpenAIRE

Williams, N S; Johnston, D

1980-01-01

Thirty randomly selected patients with permanent colostomies entered a prospective controlled trial comparing colostomy irrigation with spontaneous action. Each patient was interviewed and examined before irrigation was begun and again after the technique had been used for three months. Each then reverted to spontaneous action for a further three months and was then reassessed. Eight patients abandoned irrigation and 22 (73%) adhered to the protocol. Irrigation caused no mishaps or complicati...

Broadband enhancement of spontaneous emission in a photonic-plasmonic structure

DEFF Research Database (Denmark)

Zhu, Xiaolong; Xie, Fengxian; Shi, Lei

2012-01-01

We demonstrate that a broadband enhancement of spontaneous emission can be achieved within a photonic-plasmonic structure. The structure can strongly modify the spontaneous emission by exciting plasmonic modes. Because of the excited plasmonic modes, an enhancement up to 30 times is observed, lea......, leading to a 4 times broader emission spectrum. The reflectance measurement and the finite-difference time-domain simulation are carried out to support these results....

Radiological evaluation of spontaneous pneumoperitoneum

International Nuclear Information System (INIS)

Kim, H. S.; Kim, J. D.; Rhee, H. S.

1982-01-01

112 cases of spontaneous penumoperitoneum, the causes of which were confirmed by clinical and surgical procedure at Presbyterian Medical Center from January, 1977 to July, 1981 were reviewed radiologically. The results were as follows: 1. Perforation of duodenal ulcer (46/112: 41.1%), stomach ulcer (22/112: 19.6%), and stomach cancer (11/112: 9.8%) were the three most common causes of spontaneous penumoperitoneum. These were 70.5% of all causes. 2. The most common site of free gas was both subdiaphragmatic areas (46: 41.1%). Others were Rt. subdiaphragmatic only (31: 27.7%), both subdiaphragmatic with subhepatic (16: 14.3%), Rt. subdiaphragmatic with subhepatic (7: 6.2%), Rt. subdiaphragmatic only (5: 4.4%), diffuse in abdomen (4: 3.6%), and subhepatic only (3: 2.7%). So 92.0% (103/112) were located in RUQ. 3. The radiological shape of free gas was classified: crescent (52: 46.4%) of small amount; half-moon (21: 18.8%) of moderate amount; large or diffuse (39: 34.8%) of large amount.4. The age between 31 and 60 occupied 69.1% (77/112), and male was predominant (5.2 times). 5. The patient's position showing free air most frequently was erect

Spontaneously broken mass

International Nuclear Information System (INIS)

Endlich, Solomon; Nicolis, Alberto; Penco, Riccardo

2015-01-01

The Galilei group involves mass as a central charge. We show that the associated superselection rule is incompatible with the observed phenomenology of superfluid helium 4: this is recovered only under the assumption that mass is spontaneously broken. This remark is somewhat immaterial for the real world, where the correct space-time symmetries are encoded by the Poincaré group, which has no central charge. Yet it provides an explicit example of how superselection rules can be experimentally tested. We elaborate on what conditions must be met for our ideas to be generalizable to the relativistic case of the integer/half-integer angular momentum superselection rule.

Spontaneous rupture of the spleen – a rare and potentially fatal ...

African Journals Online (AJOL)

Spontaneous (non-traumatic) rupture of the normal spleen in pregnancy is a rare clinical event that can endanger the lives of both mother and baby. The aetiology of the condition is unknown, but it occurs most commonly in multiple pregnancies and in the third trimester. We present a case of a spontaneous splenic rupture ...

Spontaneous stress fractures of the femoral neck

International Nuclear Information System (INIS)

Dorne, H.L.; Lander, P.H.

1985-01-01

The diagnosis of spontaneous stress fractures of the femoral neck, a form of insufficiency stress fracture, can be missed easily. Patients present with unremitting hip pain without a history of significant trauma or unusual increase in daily activity. The initial radiographic features include osteoporosis, minor alterations of trabecular alignment, minimal extracortical or endosteal reaction, and lucent fracture lines. Initial scintigraphic examinations performed in three of four patients showed focal increased radionuclide uptake in two and no focal abnormality in one. Emphasis is placed on the paucity of early findings. Evaluation of patients with persistent hip pain requires a high degree of clinical suspicion and close follow-up; the sequelae of undetected spontaneous fractures are subcapital fracture with displacement, angular deformity, and a vascular necrosis of the femoral head

Spontaneous Regression of Choroidal Neovascularization in a Patient with Pattern Dystrophy

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Anastasios Anastasakis

2016-01-01

Full Text Available Purpose. To present a case of a patient with pattern dystrophy (PD associated choroidal neovascularization (CNV that resolved spontaneously without treatment. Methods. A 69-year-old male patient was referred to our unit, for evaluation of a recent visual loss (metamorphopsias in his left eye. Fundus examination, fundus autofluorescence imaging, and fluorescein angiography showed a choroidal neovascular membrane in his left eye. Since visual acuity was satisfactory the patient elected observation. Clinical examination and OCT testing were repeated at 6 and 12 months after presentation. Results. Visual acuity remained stable at the level of 0.9 (baseline BCVA during the follow-up period (12 months. Repeat OCT testing showed complete spontaneous regression of the choroidal neovascular membrane without evidence of intra- or subretinal fluid in both follow-up visits. Conclusions. Spontaneous regression of choroidal neovascularization can occur in patients with retinal dystrophies and associated choroidal neovascular membranes. The decision to treat or observe these patients relies strongly on the presenting visual acuity, since, in isolated instances, spontaneous resolution of choroidal neovascularization may occur.

Mixed quantum-classical electrodynamics: Understanding spontaneous decay and zero-point energy

Science.gov (United States)

Li, Tao E.; Nitzan, Abraham; Sukharev, Maxim; Martinez, Todd; Chen, Hsing-Ta; Subotnik, Joseph E.

2018-03-01

The dynamics of an electronic two-level system coupled to an electromagnetic field are simulated explicitly for one- and three-dimensional systems through semiclassical propagation of the Maxwell-Liouville equations. We consider three flavors of mixed quantum-classical dynamics: (i) the classical path approximation (CPA), (ii) Ehrenfest dynamics, and (iii) symmetrical quasiclassical (SQC) dynamics. Our findings are as follows: (i) The CPA fails to recover a consistent description of spontaneous emission, (ii) a consistent "spontaneous" emission can be obtained from Ehrenfest dynamics, provided that one starts in an electronic superposition state, and (iii) spontaneous emission is always obtained using SQC dynamics. Using the SQC and Ehrenfest frameworks, we further calculate the dynamics following an incoming pulse, but here we find very different responses: SQC and Ehrenfest dynamics deviate sometimes strongly in the calculated rate of decay of the transient excited state. Nevertheless, our work confirms the earlier observations by Miller [J. Chem. Phys. 69, 2188 (1978), 10.1063/1.436793] that Ehrenfest dynamics can effectively describe some aspects of spontaneous emission and highlights interesting possibilities for studying light-matter interactions with semiclassical mechanics.

Recurrence rate after thoracoscopic surgery for primary spontaneous pneumothorax.

Science.gov (United States)

Dagnegård, Hanna H; Rosén, Alice; Sartipy, Ulrik; Bergman, Per

2017-08-01

There is an on-going discussion regarding the recurrence rate after surgery for primary spontaneous pneumothorax by video assisted thoracic surgery (VATS) or by thoracotomy access. This study aimed to describe the recurrence rate, and to identify a possible learning curve, following surgery for primary spontaneous pneumothorax by VATS. All patients who underwent surgery for primary spontaneous pneumothorax by VATS at Karolinska University Hospital 2004-2013 were reviewed. Preoperative and operative characteristics were obtained from medical records. Patients were followed-up through telephone interviews or questionnaires and by review of medical records. The primary outcome of interest was time to recurrence of pneumothorax requiring intervention. Outcomes were compared between patients operated during 2004-June 2010 and July 2010-2013. 219 patients who underwent 234 consecutive procedures were included. The mean follow-up times were 6.3 and 2.9 years in the early and late period, respectively. The postoperative recurrence rate in the early period was 16% (11%-25%), 18% (12%-27%), and 18% (12%-27%), at 1, 3 and 5 years, compared to 1.7% (0.4%-6.8%), 7.6% (3.7%-15%), and 9.8% (4.8%-19%) at 1, 3 and 5 years, in the late period (p = 0.016). We found that the recurrence rate after thoracoscopic surgery for primary spontaneous pneumothorax decreased significantly during the study period. Our results strongly suggest that thoracoscopic surgery for pneumothorax involve a substantial learning curve.

Starting and Stopping Spontaneous Family Conflicts.

Science.gov (United States)

Vuchinich, Samuel

1987-01-01

Examined how 52 nondistressed families managed spontaneous verbal conflicts during family dinners. Found conflict initiation to be evenly distributed across family roles. Extension of conflict was constrained by constant probability of a next conflict move occurring. Most conflicts ended with no resolution. Mothers were most active in closing…

Early removal of odontoma resulting in spontaneous eruption of the impacted teeth

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Achmad Harijadi

2010-06-01

Full Text Available Background: Compound odontomas in the anterior maxilla during mixed dentition frequently cause obstruction to the eruption pathway of permanent upper anterior teeth. Removal of the odontomas may or may not lead to spontaneous eruption of the impacted teeth depending on the age when the surgery is performed, the size of the lesion, and the stage of tooth development of the involved teeth. Purpose: This paper attempts to emphasize the importance of early removal of compound odontoma to enable spontaneous eruption of the affected teeth. Case: A case of odontoma in the anterior maxilla causing failure of eruption and delayed root formation of upper right permanent lateral incisor and canine in a 10-year-old male patient is presented. Case management: The odontoma was surgically removed under general anesthesia and histology result confirmed the diagnosis of compound odontoma. A three-year post surgical follow up showed spontaneous eruption as well as continued root formation of the two affected teeth. Conclusion: Removal of odontoma may lead to spontaneous eruption of the affected teeth if their root development are not completed.Latar belakang: Compound odontoma pada daerah anterior maksila pada masa geligi pergantian sering menyebabkan hambatan erupsi pada gigi permanen penggantinya. Kemungkinan terjadinya erupsi spontan gigi permanen yang impaksi setelah pengambilan odontoma tergantung dari: umur penderita pada saat dilakukan operasi, ukuran lesi odontoma dan tahapan perkembangan gigi permanen yang terlibat. Tujuan: Laporan kasus ini ingin menekankan pentingnya pengambilan compound odontoma sedini mungkin untuk memberi kesempatan tumbuhnya gigi permanen yang terlibat dan erupsi secara spontan. Kasus: Ditampilkan sebuah kasus compound odontoma pada regio maksila anterior menyebabkan gagalnya erupsi dan terlambatnya pembentukan akar gigi insisif kedua dan kaninus permanent rahang atas kanan pada penderita anak laki-laki berumur 10 tahun

Neutron-antineutron oscillation and baryonic majoron: low scale spontaneous baryon violation

Energy Technology Data Exchange (ETDEWEB)

Berezhiani, Zurab [Universita dell' Aquila, Dipartimento delle Scienze Fisiche e Chimiche, L' Aquila (Italy); INFN, Laboratori Nazionali Gran Sasso, L' Aquila (Italy)

2016-12-15

We discuss the possibility that baryon number B is spontaneously broken at low scales, of the order of MeV or even smaller, inducing the neutron-antineutron oscillation at the experimentally accessible level. An associated Goldstone particle-baryonic majoron can have observable effects in neutron to antineutron transitions in nuclei or dense nuclear matter. By extending baryon number to an anomaly-free B - L symmetry, the baryo-majoron can be identified with the ordinary majoron associated with the spontaneous breaking of lepton number, and it can have interesting implications for neutrinoless 2β decay with the majoron emission. We also discuss the hypothesis that baryon number can be spontaneously broken by QCD itself via the six-quark condensates. (orig.)

Cannabis increased the risk of primary spontaneous pneumothorax in tobacco smokers

DEFF Research Database (Denmark)

Hedevang Olesen, Winnie; Katballe, Niels; Sindby, Jesper Eske

2017-01-01

OBJECTIVES: Previous smaller case series suggested that cannabis smoking may cause spontaneous pneumothorax, but this finding remains controversial. We investigated the possible association between smoking tobacco and cannabis and the risk of having a primary spontaneous pneumothorax in a large...... tobacco and cannabis were obtained from questionnaires presented on admittance. We compared our findings with those of a population-based control group matched by age, sex and geographical area. Calculated odds ratios were compared using the Fisher’s exact test for small frequencies and the χ2 test.......61–14.14, P cannabis and tobacco in men increased the risk of spontaneous pneumothorax significantly (odds ratio = 8.74, 95% confidence interval: 4.30–19.51, P 

Surgical treatment versus conventional chest tube drainage in primary spontaneous pneumothorax

DEFF Research Database (Denmark)

Olesen, Winnie Hedevang; Katballe, Niels; Sindby, Jesper Eske

2018-01-01

OBJECTIVES: Primary spontaneous pneumothorax frequently recurs after chest tube management. Evidence is lacking whether patients may benefit from surgery following their first episode. METHODS: We performed a multicentre, randomized trial and enrolled young, otherwise healthy patients admitted...... with their first episode of primary spontaneous pneumothorax and treated using conventional chest tube drainage. Patients underwent high-resolution computed tomography on fully expanded lungs, and using web-based randomization, we assigned patients to continued conservative chest tube treatment or chest tube...... treatment to prevent recurrence in patients with their first presentation of primary spontaneous pneumothorax and should be the standard of care when high-resolution computed tomography demonstrates bullae ≥2 cm. Clinical trial registration: ClinicalTrial.gov: NCT 02866305....

Placental histology in spontaneous and indicated preterm birth: A case control study

NARCIS (Netherlands)

Nijman, Tobias A. J.; van Vliet, Elvira O. G.; Benders, Manon J. N.; Mol, Ben Willem J.; Franx, Arie; Nikkels, Peter G. J.; Oudijk, Martijn A.

2016-01-01

Placental pathology is an important contributor in preterm birth, both spontaneous and indicated. The aim of this study was to describe and compare placental histological features of spontaneous preterm birth versus indicated preterm birth. A case control study was performed at the University

[Quantitative spectrum analysis of characteristic gases of spontaneous combustion coal].

Science.gov (United States)

Liang, Yun-Tao; Tang, Xiao-Jun; Luo, Hai-Zhu; Sun, Yong

2011-09-01

Aimed at the characteristics of spontaneous combustion gas such as a variety of gases, lou limit of detection, and critical requirement of safety, Fourier transform infrared (FTIR) spectral analysis is presented to analyze characteristic gases of spontaneous combustion In this paper, analysis method is introduced at first by combing characteristics of absorption spectra of analyte and analysis requirement. Parameter setting method, sample preparation, feature variable abstract and analysis model building are taken into consideration. The methods of sample preparation, feature abstraction and analysis model are introduced in detail. And then, eleven kinds of gases were tested with Tensor 27 spectrometer. CH4, C2H6, C3H8, iC4H10, nC4H10, C2 H4, C3 H6, C3 H2, SF6, CO and CO2 were included. The optical path length was 10 cm while the spectra resolution was set as 1 cm(-1). The testing results show that the detection limit of all analytes is less than 2 x 10(-6). All the detection limits fit the measurement requirement of spontaneous combustion gas, which means that FTIR may be an ideal instrument and the analysis method used in this paper is competent for spontaneous combustion gas measurement on line.

Management of paediatric spontaneous pneumothorax: a multicentre retrospective case series.

Science.gov (United States)

Robinson, Paul D; Blackburn, Carol; Babl, Franz E; Gamage, Lalith; Schutz, Jacquie; Nogajski, Rebecca; Dalziel, Stuart; Donald, Colin B; Druda, Dino; Krieser, David; Neutze, Jocelyn; Acworth, Jason; Lee, Mark; Ngo, Peter K

2015-10-01

Paediatric guidelines are lacking for management of spontaneous pneumothorax. Adult patient-focused guidelines (British Thoracic Society 2003 and 2010) introduced aspiration as first-line intervention for primary spontaneous pneumothorax (PSP) and small secondary spontaneous pneumothoraces (SSP). Paediatric practice is unclear, and evidence for aspiration success rates is urgently required to develop paediatric-specific recommendations. Retrospective analysis of PSP and SSP management at nine paediatric emergency departments across Australia and New Zealand (2003-2010) to compare PSP and SSP management. 219 episodes of spontaneous pneumothorax occurred in 162 children (median age 15 years, 71% male); 155 PSP episodes in 120 children and 64 SSP episodes in 42 children. Intervention in PSP vs SSP episodes occurred in 55% (95% CI 47% to 62%) vs 70% (60% to 79%), pmanagement, PSP and SSP management did not differ and ICC insertion was the continuing preferred intervention. Overall success of aspiration was lower than reported results for adults, although success was greater for small than for large pneumothoraces. Paediatric prospective studies are urgently required to determine optimal paediatric interventional management strategies. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Brain-derived neurotrophic factor is increased in serum and skin levels of patients with chronic spontaneous urticaria.

Science.gov (United States)

Rössing, K; Novak, N; Mommert, S; Pfab, F; Gehring, M; Wedi, B; Kapp, A; Raap, U

2011-10-01

Chronic spontaneous urticaria is triggered by many direct and indirect aggravating factors including autoreactive/autoimmune mechanisms, infections, non-allergic and pseudoallergic intolerance reactions. However, the role of neuroimmune mechanisms in chronic spontaneous urticaria so far is unclear. Thus, we wanted to address the regulation of the neurotrophin brain-derived neurotrophic factor (BDNF) in serum and inflammatory skin of patients with chronic spontaneous urticaria in comparison to subjects with healthy skin. Fifty adult patients with chronic spontaneous urticaria and 23 skin-healthy subjects were studied. Chronic spontaneous urticaria was defined as recurrent weals for more than 6 weeks. Autologous serum skin test was performed in all patients with chronic spontaneous urticaria and BDNF serum levels were analysed by enzyme immunoassay in all subjects. Furthermore, skin biopsies were taken from weals of eight patients with chronic spontaneous urticaria as well as from healthy skin of eight controls to evaluate the expression of BDNF and its receptors including tyrosine kinase (trk) B and pan-neurotrophin receptor p75(NTR) by immunohistochemistry. BDNF serum levels were detectable in all subjects studied. However, BDNF levels were significantly higher in patients with chronic spontaneous urticaria compared to non-atopic skin-healthy controls (Pchronic spontaneous urticaria compared with controls (Pchronic spontaneous urticaria and controls and no difference in BDNF serum levels between autologous serum skin test-positive (n=23) and -negative (n=27) patients with chronic spontaneous urticaria. This study shows that BDNF is increased in serum and diseased skin of patients with chronic spontaneous urticaria, suggesting a role for neurotrophins in the pathophysiology of this chronic inflammatory skin disease. Further studies are needed to address the functional role of BDNF on key target effector cells in chronic spontaneous urticaria to establish new

L’habitat spontané comme un outil de développement urbain. Le cas de Bangkok Spontaneous Housing as a Tool for Urban Development, the Case of Bangkok

Directory of Open Access Journals (Sweden)

Fanny Gerbeaud

2011-10-01

Full Text Available En Thaïlande, les ensembles d’habitat spontané s’étendent à toute la capitale, malgré des politiques publiques qui visent à les contrer. Ce sont aujourd’hui de véritables morceaux de ville qui dynamisent l’espace urbain, car étroitement liés à l’identité et à l’histoire de la ville. L’opposition entre habitat spontané et « logement formel », fréquente tant dans les productions scientifiques que dans les représentations, mérite donc d���être interrogée à Bangkok. À partir d’une analyse spatiale et architecturale, nous avons abordé l’habitat spontané comme une manière de fabriquer la ville centrée sur l’appropriation : au moins sous trois formes (habitat spontané pur, ancien, greffé, il assure par sa flexibilité la continuité du tissu urbain et s’y assimile progressivement. Si pour les autorités locales les communautés de bidonvilles demeurent un signe de sous-développement, certains architectes et acteurs y voient une source d’inspiration ainsi qu’un patrimoine populaire à préserver. Une métropolisation accrue et la mondialisation des échanges économiques, culturels, politiques, amènent de nouvelles modalités de négociation de l’espace urbain qui redéfinissent le statut de l’habitat spontané. Avec l’apparition de nouvelles professions (architecte des communautés et orientations dans la manière de concevoir des projets urbains (processus participatif notamment, l’habitat spontané s’affirme peu à peu comme un outil de développement de la capitale.In Thailand, despite some public policies, spontaneous settlements spread all over the city. Closely related to the city’s history and identity they are nowadays real dynamic neighbourhoods. The opposition between spontaneous housing and “formal housing”, common in both the scientific publications and representations, is yet to be questioned in Bangkok. Through an architectural and spatial analysis, we

Spontaneous Rapid Resolution of Acute Epidural Hematoma in Childhood

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Ismail Gülşen

2013-01-01

Full Text Available Acute epidural hematoma is a critical emergency all around the world, and its aggressive diagnosis and treatment are of vital importance. Emergent surgical evacuation of the hematoma is known as standard management; however, conservative procedures are also used for small ones. Spontaneous rapid resolution of these hematomas has also been reported in eight pediatric cases. Various theories have been proposed to explain the underlying pathophysiology of this resolution. Herein, we are reporting a new pediatric case with spontaneously resolving acute epidural hematoma 12 hours after admission to the emergency room.

Spontaneous Uterine Perforation due to Pyometra Presenting as Acute Abdomen

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Loabat Geranpayeh

2006-01-01

Full Text Available Spontaneous perforation of the uterus is rare, its incidence being about 0.01%–0.05%. We report a rare case of diffuse peritonitis caused by spontaneously perforated pyometra. A 63-year-old woman with severe abdominal pain was admitted to our hospital. Laparotomy was performed because of the suspicion of gastrointestinal perforation with generalized peritonitis. At laparotomy, about 900 mL of pus was found in the peritoneal cavity. There were no abnormal findings in the alimentary tract, liver, or gallbladder. A total abdominal hysterectomy with bilateral salpingo-oophorectomy was performed. Pathological investigation of the surgical specimen revealed endometritis and myometritis of the uterus; but there was no evidence of malignancy, and the cervical canal was patent. Although spontaneously perforated pyometra is rare, a perforated pyometra should therefore also be considered when elderly women present with acute abdominal pain.

Spontaneous osteonecrosis of the knee associated with tibial plateau and femoral condyle insufficiency stress fracture

Energy Technology Data Exchange (ETDEWEB)

Narvaez, J.A.; Narvaez, J.; Lama, E.De; Sanchez, A. [Department of Magnetic Resonance Imaging, IDI Hospital Duran i Reynals, Ciutat Sanitaria i Universitaria de Bellvitge, Gran Via s/n, 08907, L' Hospitalet de Llobregat (Barcelona) (Spain)

2003-08-01

The purpose of this article is to describe the association between spontaneous osteonecrosis and insufficiency stress fractures of the knee. To determine whether insufficiency stress fracture is associated with spontaneous osteonecrosis of the knee, we retrospectively reviewed the medical charts and imaging studies of all patients with spontaneous osteonecrosis of the knee, studied by MR imaging, seen in a tertiary hospital over an 8-year period. Four women (age range 66-84 years) presented spontaneous osteonecrosis of the knee associated with insufficiency stress fracture of the medial tibial plateau. One of these patients also presented a concomitant insufficiency stress fracture of the medial femoral condyle. Radiographs were diagnostic of spontaneous osteonecrosis of the medial femoral condyle in three cases, and insufficiency stress fracture of the medial tibial plateau was detected in one case. Magnetic resonance imaging allows the diagnosis of both conditions in all four cases. Spontaneous osteonecrosis of the knee may be associated with insufficiency stress fracture of the medial femoral condyle and the medial tibial plateau. This association provides additional arguments in favor of the traumatic etiology of spontaneous osteonecrosis of knee. (orig.)

Spontaneous osteonecrosis of the knee associated with tibial plateau and femoral condyle insufficiency stress fracture

International Nuclear Information System (INIS)

Narvaez, J.A.; Narvaez, J.; Lama, E.De; Sanchez, A.

2003-01-01

The purpose of this article is to describe the association between spontaneous osteonecrosis and insufficiency stress fractures of the knee. To determine whether insufficiency stress fracture is associated with spontaneous osteonecrosis of the knee, we retrospectively reviewed the medical charts and imaging studies of all patients with spontaneous osteonecrosis of the knee, studied by MR imaging, seen in a tertiary hospital over an 8-year period. Four women (age range 66-84 years) presented spontaneous osteonecrosis of the knee associated with insufficiency stress fracture of the medial tibial plateau. One of these patients also presented a concomitant insufficiency stress fracture of the medial femoral condyle. Radiographs were diagnostic of spontaneous osteonecrosis of the medial femoral condyle in three cases, and insufficiency stress fracture of the medial tibial plateau was detected in one case. Magnetic resonance imaging allows the diagnosis of both conditions in all four cases. Spontaneous osteonecrosis of the knee may be associated with insufficiency stress fracture of the medial femoral condyle and the medial tibial plateau. This association provides additional arguments in favor of the traumatic etiology of spontaneous osteonecrosis of knee. (orig.)

VBAC In Women Undergoing IOL With Dinoprostone Versus Spontaneous Labor

OpenAIRE

Alves, João; Vilhena, Cristina; Tomás, Cláudia; Antunes, Isabel Lobo; Metello, José; Natário, Isabel; Puga, Marco; Casal, Ester

2015-01-01

Sem PDF OBJECTIVE: To compare the rate of vaginal birth in women attempting vaginal birth after caesarean delivery (VBAC) through labour induction with dinoprostone versus a trial of spontaneous labour. METHODS: A 10-year retrospective cohort study in a tertiary care hospital of women with one prior caesarean delivery. Women who attempted VBAC with labour induction with dinoprostone were compared with women undergoing spontaneous labour. Logistic regression analyses were performed to asses...

Spontaneous acute subdural hematoma in a patient with multiple myeloma

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Abrar Ahad Wani

2012-01-01

Full Text Available Acute spontaneous subdural hematoma in a patient of multiple myeloma receiving chemotherapy is an unknown event, needing an urgent neurosurgical management. We report this patient who presented with progressive neurological deterioration and a low platelet count. She was successfully managed by craniotomy and evacuation of subdural hematoma with intraoperative transfusion of platelets. The acute spontaneous subdural hematoma in her was probably related to the bleeding diathesis due to thrombocytopenia associated with chemotherapy.

The development of spontaneous gender stereotyping in childhood: relations to stereotype knowledge and stereotype flexibility.

Science.gov (United States)

Banse, Rainer; Gawronski, Bertram; Rebetez, Christine; Gutt, Hélène; Morton, J Bruce

2010-03-01

The development of spontaneous gender stereotyping in children was investigated using the newly developed Action Interference Paradigm (AIP). This task consists of assigning gender-stereotypical toys as quickly as possible to boys and girls in either a stereotype-congruent or a stereotype-incongruent manner. A pilot study with 38 children (mean age 5.1 years) provided evidence for spontaneous gender stereotyping in the AIP, which was reflected in higher latencies for stereotype-incongruent compared with stereotype-congruent toy assignments. The main study, with 66 children (aged 5, 8 and 11 years), compared the development of spontaneous stereotyping with established measures of stereotype flexibility and stereotype knowledge. Stereotype flexibility showed a strong increase from age 5 to 11. In contrast, stereotype knowledge and spontaneous stereotyping remained stable at high levels. The results provide evidence for a dissociation between stereotype flexibility and spontaneous stereotyping, suggesting that spontaneous stereotyping may be more closely related to stereotype knowledge than to stereotype flexibility.

Spontaneous swallowing frequency has potential to identify dysphagia in acute stroke.

Science.gov (United States)

Crary, Michael A; Carnaby, Giselle D; Sia, Isaac; Khanna, Anna; Waters, Michael F

2013-12-01

Spontaneous swallowing frequency has been described as an index of dysphagia in various health conditions. This study evaluated the potential of spontaneous swallow frequency analysis as a screening protocol for dysphagia in acute stroke. In a cohort of 63 acute stroke cases, swallow frequency rates (swallows per minute [SPM]) were compared with stroke and swallow severity indices, age, time from stroke to assessment, and consciousness level. Mean differences in SPM were compared between patients with versus without clinically significant dysphagia. Receiver operating characteristic curve analysis was used to identify the optimal threshold in SPM, which was compared with a validated clinical dysphagia examination for identification of dysphagia cases. Time series analysis was used to identify the minimally adequate time period to complete spontaneous swallow frequency analysis. SPM correlated significantly with stroke and swallow severity indices but not with age, time from stroke onset, or consciousness level. Patients with dysphagia demonstrated significantly lower SPM rates. SPM differed by dysphagia severity. Receiver operating characteristic curve analysis yielded a threshold of SPM≤0.40 that identified dysphagia (per the criterion referent) with 0.96 sensitivity, 0.68 specificity, and 0.96 negative predictive value. Time series analysis indicated that a 5- to 10-minute sampling window was sufficient to calculate spontaneous swallow frequency to identify dysphagia cases in acute stroke. Spontaneous swallowing frequency presents high potential to screen for dysphagia in acute stroke without the need for trained, available personnel.

Spontaneous Swallowing Frequency [Has Potential to] Identify Dysphagia in Acute Stroke

Science.gov (United States)

Carnaby, Giselle D; Sia, Isaac; Khanna, Anna; Waters, Michael

2014-01-01

Background and Purpose Spontaneous swallowing frequency has been described as an index of dysphagia in various health conditions. This study evaluated the potential of spontaneous swallow frequency analysis as a screening protocol for dysphagia in acute stroke. Methods In a cohort of 63 acute stroke cases swallow frequency rates (swallows per minute: SPM) were compared to stroke and swallow severity indices, age, time from stroke to assessment, and consciousness level. Mean differences in SPM were compared between patients with vs. without clinically significant dysphagia. ROC analysis was used to identify the optimal threshold in SPM which was compared to a validated clinical dysphagia examination for identification of dysphagia cases. Time series analysis was employed to identify the minimally adequate time period to complete spontaneous swallow frequency analysis. Results SPM correlated significantly with stroke and swallow severity indices but not with age, time from stroke onset, or consciousness level. Patients with dysphagia demonstrated significantly lower SPM rates. SPM differed by dysphagia severity. ROC analysis yielded a threshold of SPM ≤ 0.40 which identified dysphagia (per the criterion referent) with 0.96 sensitivity, 0.68 specificity, and 0.96 negative predictive value. Time series analysis indicated that a 5 to 10 minute sampling window was sufficient to calculate spontaneous swallow frequency to identify dysphagia cases in acute stroke. Conclusions Spontaneous swallowing frequency presents high potential to screen for dysphagia in acute stroke without the need for trained, available personnel. PMID:24149008

Automatic recognition of spontaneous emotions in speech using acoustic and lexical features

NARCIS (Netherlands)

Raaijmakers, S.; Truong, K.P.

2008-01-01

We developed acoustic and lexical classifiers, based on a boosting algorithm, to assess the separability on arousal and valence dimensions in spontaneous emotional speech. The spontaneous emotional speech data was acquired by inviting subjects to play a first-person shooter video game. Our acoustic

Recurrent Primary Spontaneous Pneumothorax is Common Following Chest Tube and Conservative Treatment.

Science.gov (United States)

Olesen, Winnie Hedevang; Lindahl-Jacobsen, Rune; Katballe, Niels; Sindby, Jesper Eske; Titlestad, Ingrid Louise; Andersen, Poul Erik; Licht, Peter Bjørn

2016-09-01

Previous studies on primary spontaneous pneumothorax reported variable recurrence rates, but they were based on heterogeneous patient populations including secondary pneumothorax. We investigated young patients with primary spontaneous pneumothorax exclusively and used a national registry to track readmissions and calculate independent predictors of recurrence. A prospective cohort study of consecutive young patients who were admitted over a 5-year period with their first episode of primary spontaneous pneumothorax and treated conservatively with a chest tube. Baseline characteristics were obtained from questionnaires presented on admittance. All patients were discharged with fully expanded lungs on chest radiography. Patient charts were identified in the national electronic patient registry for detailed information on readmissions due to recurrent spontaneous pneumothorax. We included 234 patients. Male/female = ratio 5/1. After a median observation period of 3.6 years (range 1-6 years), recurrent pneumothorax was observed in 54 %. Ipsilateral recurrence was the most common (79 %) but 30 % also experienced contralateral pneumothorax during the study period. Females had a significantly higher age at debut (p pneumothorax in younger patients with their first episode had a much higher recurrence rate than previously reported. Every doctor who treats patients with primary spontaneous pneumothorax should be aware and patients informed.

Unusual case of pancreatic inflammatory myofibroblastic tumor associated with spontaneous splenic rupture

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Hassan Fadi K

2010-11-01

Full Text Available Abstract Background Spontaneous splenic rupture considered a relatively rare but life threatening. The three commonest causes of spontaneous splenic rupture are malignant hematological diseases, viral infections and local inflammatory and neoplastic disorders. We describe a unique and unusual case of inflammatory myofibroblastic tumor of the tail of pancreas presented with massively enlarged spleen and spontaneous splenic rupture. Case presentation A 19 years old male patient with no significant past medical history presented to emergency room with abdominal pain and fatigue. Massively enlarged spleen was detected. Hypotension and rapid reduction of hemoglobin level necessitated urgent laparatomy. About 1.75 liters of blood were found in abdominal cavity. A large tumor arising from the tail of pancreas and local rupture of an enlarged spleen adjacent to the tumor were detected. Distal pancreatectomy and splenectomy were performed. To our knowledge, we report the first case of massively enlarged spleen that was complicated with spontaneous splenic rupture as a result of splenic congestion due to mechanical obstruction caused by an inflammatory myofibroblastic tumor of the tail of pancreas. A review of the literature is also presented. Conclusion Inflammatory myofibroblastic tumor of the tail of pancreas should be included in the differential diagnosis of the etiological causes of massively enlarged spleen and spontaneous splenic rupture.

A clinical and radiological study on spontaneous pneumothorax

International Nuclear Information System (INIS)

Jang, Kyung Jae; Kim, Jin Wook; Kim, Byung Soo; Choi, Myung Gwon

1982-01-01

A clinical and radiological study was done on 96 cases of spontaneous pneumothorax, encountered in the Dept. of Radiology, Busan National University Hospital during last 3 years from March 1979 to March 1982. The result were summarized as follows: 1. In the age distribution, the ages between 20 and 39 years were most highest, as 54 cases (56.3%). In the sex distribution, the ratio of male to female was 5 : 1 in male predominance. 2. The underlying pathology of the total 96 cases of spontaneous pneumothorax were of tuberculous origin in 33.3 % and non-tuberculous origin in 66.7%. And below 20 years, most were of non- tuberculous origin. 3. In the cases of lung collapse over 2/3, non-tuberculous origin was more than tuberculous origin and had characteristics of significant mediastinal shifting, in contrast to lower percentage of fluid level by chest radiography. 4. The rupture of biebs or bullae was the main immediate causes of spontaneous pneumothorax, independent of the underlying pathology. 5. In only 27 cases (28.1%) among total 96 cases, bullae or biebs could be detected on the chest radiography. 6. In treatment of spontaneous pneumothorax, the closed thoracotomy with under water seal drainage is accepted to be the general method of treatment. But open thoracotomy is considered as the best useful therapeutic procedure to prevent the recurrence, whenever bullae or blebs are found on the chest radiography. 7. In the cases of closed thoracotomy, the recurrent rate was 25.0% and most cases were found at the ipsilateral side of the first attack. 8. Within a week, the collapsed lung were well expanded in most cases of total 96 cases, after closed thoracotomy

Spontaneous Pneumomediastinum: Hamman Syndrome

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Tushank Chadha, BS

2018-04-01

significant fat stranding. The image also showed an intraluminal stent traversing the gastric antrum and gastric pylorus with no indication of obstruction. Circumferential mural thickening of the gastric antrum and body were consistent with the patient’s history of gastric adenocarcinoma. The shotty perigastric lymph nodes with associated fat stranding, along the greater curvature of the distal gastric body suggested local regional nodal metastases and possible peritoneal carcinomatosis. The thoracic CT scans showed extensive pneumomediastinum that tracked into the soft tissues of the neck, which given the history of vomiting also raised concern for esophageal perforation. There was still no evidence of mediastinal abscess or fat stranding. Additionally, a left subclavian vein port catheter, which terminates with tip at the cavoatrial junction of the superior vena cava can also be seen on the image. Discussion: Spontaneous Pneumomediastinum, also known as Hamman syndrome, is defined by the uncommon incidence of free air in the mediastinum due to the bursting of alveoli, as a result of extended spells of shouting, coughing, or vomiting.1,2 The condition is diagnosed when a clear cause (aerodigestive rupture, barotrauma, infection secondary to gas-forming organisms3 for pneumomediastinum cannot be clearly identified on diagnostic studies. Macklin and Macklin were the first to note the pathogenesis of the syndrome and explained that the common denominator to spontaneous pneumomediastinum was that increased alveolar pressure leads to alveolar rupture.3 Common clinical findings for spontaneous pneumomediastinum include: chest pain, dyspnea, cough, and emesis.4 The condition is not always readily recognized on initial presentation in part for its rare incidence, estimated to be approximately 1 in every 44,500 ED patients3and also because of the non-specific presenting symptoms. For this patient, there was no clear singular cause, and therefore she received care for spontaneous

Spontaneous Tumor Lysis Syndrome

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Alicia C. Weeks MD

2015-08-01

Full Text Available Tumor lysis syndrome (TLS is a known complication of malignancy and its treatment. The incidence varies on malignancy type, but is most common with hematologic neoplasms during cytotoxic treatment. Spontaneous TLS is thought to be rare. This case study is of a 62-year-old female admitted with multisystem organ failure, with subsequent diagnosis of aggressive B cell lymphoma. On admission, laboratory abnormalities included renal failure, elevated uric acid (20.7 mg/dL, and 3+ amorphous urates on urinalysis. Oliguric renal failure persisted despite aggressive hydration and diuretic use, requiring initiation of hemodialysis prior to chemotherapy. Antihyperuricemic therapy and hemodialysis were used to resolve hyperuricemia. However, due to multisystem organ dysfunction syndrome with extremely poor prognosis, the patient ultimately expired in the setting of a terminal ventilator wean. Although our patient did not meet current TLS criteria, she required hemodialysis due to uric acid nephropathy, a complication of TLS. This poses the clinical question of whether adequate diagnostic criteria exist for spontaneous TLS and if the lack of currently accepted guidelines has resulted in the underestimation of its incidence. Allopurinol and rasburicase are commonly used for prevention and treatment of TLS. Although both drugs decrease uric acid levels, allopurinol mechanistically prevents formation of the substrate rasburicase acts to solubilize. These drugs were administered together in our patient, although no established guidelines recommend combined use. This raises the clinical question of whether combined therapy is truly beneficial or, conversely, detrimental to patient outcomes.

Spontaneous droplet trampolining on rigid superhydrophobic surfaces

Science.gov (United States)

Schutzius, Thomas M.; Jung, Stefan; Maitra, Tanmoy; Graeber, Gustav; Köhme, Moritz; Poulikakos, Dimos

2015-11-01

Spontaneous removal of condensed matter from surfaces is exploited in nature and in a broad range of technologies to achieve self-cleaning, anti-icing and condensation control. But despite much progress, our understanding of the phenomena leading to such behaviour remains incomplete, which makes it challenging to rationally design surfaces that benefit from its manifestation. Here we show that water droplets resting on superhydrophobic textured surfaces in a low-pressure environment can self-remove through sudden spontaneous levitation and subsequent trampoline-like bouncing behaviour, in which sequential collisions with the surface accelerate the droplets. These collisions have restitution coefficients (ratios of relative speeds after and before collision) greater than unity despite complete rigidity of the surface, and thus seemingly violate the second law of thermodynamics. However, these restitution coefficients result from an overpressure beneath the droplet produced by fast droplet vaporization while substrate adhesion and surface texture restrict vapour flow. We also show that the high vaporization rates experienced by the droplets and the associated cooling can result in freezing from a supercooled state that triggers a sudden increase in vaporization, which in turn boosts the levitation process. This effect can spontaneously remove surface icing by lifting away icy drops the moment they freeze. Although these observations are relevant only to systems in a low-pressure environment, they show how surface texturing can produce droplet-surface interactions that prohibit liquid and freezing water-droplet retention on surfaces.

Spontaneous pneumomediastinum: A rare complication of methamphetamine use.

Science.gov (United States)

Albanese, Jessica; Gross, Cole; Azab, Mohamed; Mahalean, Sinziana; Makar, Ranjit

2017-01-01

To present an unusual case of spontaneous pneumomediastinum subsequent to recreational amphetamine use. A young African American adult male was admitted to internal medicine service for treatment of rhabdomyolysis secondary to methamphetamine use. On admission, he was complaining of chest pain in addition to nausea and generalized muscle aches. By his second hospital day, chest pain had resolved yet physical exam demonstrated crepitation of the anterior chest and left axilla. Portable chest x-ray revealed subcutaneous emphysema in addition to pneumomediastinum. Spontaneous pneumomediastinum is a rare complication of amphetamine use that is often associated with subcutaneous emphysema and can be diagnosed with chest x-ray. Management is conservative, with observation, pain control, and supplemental oxygen as needed.

Spontaneous splenic rupture. Radiological findings in three cases

International Nuclear Information System (INIS)

Arenal, F.; Barrera, J.; Merino, S.; Pedrosa, C. S.

1999-01-01

Spontaneous splenic rupture not associated with previous trauma is an uncommon disease. It can appear in the course of multiple systemic diseases or over a normal splenic architecture, which is even more infrequent. An early diagnosis results mandatory, since it is a potentially fatal disease if it is not promptly diagnosed and managed. We present three cases of spontaneous splenic rupture (two sub capsular hematomas opened to peritoneum and a rupture of splenic parenchyma). One patient had infectious mononucleosis, other was in the acute phase of a chronic pancreatitis and the third one had a normal splenic architecture. We emphasize the importance of CT in the early diagnosis of this entity. (Author) 21 refs

Spontaneous Infarction in a Fibroadenoma of the Breast

Science.gov (United States)

Toy, Hatice; Esen, Haci H.; Sonmez, Fatma C.; Kucukkartallar, Tevfik

2011-01-01

Summary Background Fibroadenomas are common neoplasms in young women but occur in a wide age range from adolescent females to octogenians. Case Report A 21-year-old female patient presented with a 10-week history of a mass in her breast. Ultrasound examination demonstrated a 3.5 × 3 cm, well-circumscribed, semisolid mass. An excisional biopsy but no fine needle aspiration was performed. The patient had no history of pregnancy or lactation, or trauma or infection to the area of the lesion. The histopathological examination showed a spontaneously infarcted fibroadenoma. Conclusions Spontaneous infarction is an uncommon complication in fibroadenoma of the breast, and there are very few reported cases in the literature. PMID:21547027

Lyme Disease Presenting as a Spontaneous Knee Effusion.

Science.gov (United States)

Matzkin, Elizabeth; Suslavich, Kaytelin; Curry, Emily J

2015-11-01

Musculoskeletal complaints, which are frequently associated with Lyme disease, often prompt patients to see a physician. In particular, transient episodes of spontaneous knee effusion are common early in the progression of Lyme disease, and, if left untreated, 60% of patients diagnosed with the disease develop Lyme arthritis. This disease is easily treated with antibiotics; therefore, inclusion of Lyme disease in the differential diagnosis as a potential cause of a spontaneous knee effusion can prevent the development of more severe symptoms associated with the disease. However, the time required to receive test results and the inconsistencies between serum and synovial tests can complicate diagnosis of the disease. Copyright 2015 by the American Academy of Orthopaedic Surgeons.

Inertial Spontaneous Symmetry Breaking and Quantum Scale Invariance

Energy Technology Data Exchange (ETDEWEB)

Ferreira, Pedro G. [Oxford U.; Hill, Christopher T. [Fermilab; Ross, Graham G. [Oxford U., Theor. Phys.

2018-01-23

Weyl invariant theories of scalars and gravity can generate all mass scales spontaneously, initiated by a dynamical process of "inertial spontaneous symmetry breaking" that does not involve a potential. This is dictated by the structure of the Weyl current, $K_\\mu$, and a cosmological phase during which the universe expands and the Einstein-Hilbert effective action is formed. Maintaining exact Weyl invariance in the renormalised quantum theory is straightforward when renormalisation conditions are referred back to the VEV's of fields in the action of the theory, which implies a conserved Weyl current. We do not require scale invariant regulators. We illustrate the computation of a Weyl invariant Coleman-Weinberg potential.

Successful primary repair of late diagnosed spontaneous esophageal rupture: A case report

Directory of Open Access Journals (Sweden)

Diana Y. Kircheva

2017-01-01

Conclusion: Primary closure of late diagnosed spontaneous esophageal rupture can be successful, even when it is complicated by a prolonged delay in treatment and failed endoscopic procedures. We conclude that primary surgical repair should be attempted in patients with spontaneous esophageal rupture if tissues are viable.

Spontaneous Uterine Perforation of Pyometra Presenting as Acute Abdomen

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Toshihiro Kitai

2014-01-01

Full Text Available Pyometra is the accumulation of pus in the uterine cavity, and spontaneous perforation of pyometra resulting in generalized diffuse peritonitis is extremely uncommon. We report a rare case of diffuse peritonitis caused by spontaneous perforation of pyometra. A 66-year-old postmenopausal woman with diffuse abdominal pain and vomiting was admitted to our institution. She had a history of mixed connective-tissue disease and had been taking steroids for 20 years. Under a diagnosis of generalized peritonitis secondary to perforation of the gastrointestinal tract or uterus, supravaginal hysterectomy and bilateral salpingo-oophorectomy were performed. Unfortunately, wound dehiscence and infection occurred during the postoperative course, which were exacerbated by her immunocompromised state. Despite intensive care and a course of antibiotics, the patient died of multiple organ failure resulting from sepsis on the 36th postoperative day. Although correct diagnosis, early intervention, and proper treatment can reduce morbidity and mortality of spontaneous perforation of pyometra, if severe infection occurs, this disease can be life threatening for immunocompromised hosts.

Spontaneous regression of a large hepatocellular carcinoma: case report

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Alqutub, Adel

2011-01-01

Full Text Available The prognosis of untreated advanced hepatocellular carcinoma (HCC is grim with a median survival of less than 6 months. Spontaneous regression of HCC has been defined as the disappearance of the hepatic lesions in the absence of any specific therapy. The spontaneous regression of a very large HCC is very rare and limited data is available in the English literature. We describe spontaneous regression of hepatocellular carcinoma in a 65-year-old male who presented to our clinic with vague abdominal pain and weight loss of two months duration. He was found to have multiple hepatic lesions with elevation of serum alpha-fetoprotein (AFP level to 6,500 µg/L (normal <20 µg/L. Computed tomography revealed advanced HCC replacing almost 80% of the right hepatic lobe. Without any intervention the patient showed gradual improvement over a period of few months. Follow-up CT scan revealed disappearance of hepatic lesions with progressive decline of AFP levels to normal. Various mechanisms have been postulated to explain this rare phenomenon, but the exact mechanism remains a mystery.

A hybrid nanoantenna for highly enhanced directional spontaneous emission

Energy Technology Data Exchange (ETDEWEB)

Chou, R. Yuanying; Lu, Guowei, E-mail: guowei.lu@pku.edu.cn; Shen, Hongming; He, Yingbo; Cheng, Yuqing [State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871 (China); Perriat, Pascal [MATEIS, UMR 5510 CNRS, INSA-Lyon, Université de Lyon, Villeurbanne Cedex 69621 (France); Martini, Matteo; Tillement, Olivier [ILM, UMR 5306 CNRS, Université de Lyon, Villeurbanne Cedex 69622 (France); Gong, Qihuang [State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter, Beijing 100871 (China)

2014-06-28

Spontaneous emission modulated by a hybrid plasmonic nanoantenna has been investigated by employing finite-difference time-domain method. The hybrid nanoantenna configurations constituted by a gap hot-spot and of a plasmonic corrugated grating and a metal reflector sandwiching a SiO{sub 2} thin layer which appears promising for high spontaneous emission enhancement devices. Simulation assays show that the coupling between the gap-antenna and plasmonic corrugations reaches an ultra-high near-field enhancement factor in the excitation process. Moreover, concerning the emission process, the corrugations concentrate the far-field radiated power within a tiny angular volume, offering unprecedented collection efficiency. In the past decades, many kinds of optical antennas have been proposed and optimized to enhance single molecule detection. However, the excitation enhancement effect for single individual or dimmer plasmonic nanostructure is limited due to intrinsic nonradiative decay of the nanoparticle plasmon and quantum tunneling effect. The proposed hybrid configuration overwhelms the enhancement limit of single individual plasmonic structure. The findings provide an insight into spontaneous emission high enhancement through integrating the functions of different metallic nanostructures.

A hybrid nanoantenna for highly enhanced directional spontaneous emission

International Nuclear Information System (INIS)

Chou, R. Yuanying; Lu, Guowei; Shen, Hongming; He, Yingbo; Cheng, Yuqing; Perriat, Pascal; Martini, Matteo; Tillement, Olivier; Gong, Qihuang

2014-01-01

Spontaneous emission modulated by a hybrid plasmonic nanoantenna has been investigated by employing finite-difference time-domain method. The hybrid nanoantenna configurations constituted by a gap hot-spot and of a plasmonic corrugated grating and a metal reflector sandwiching a SiO 2 thin layer which appears promising for high spontaneous emission enhancement devices. Simulation assays show that the coupling between the gap-antenna and plasmonic corrugations reaches an ultra-high near-field enhancement factor in the excitation process. Moreover, concerning the emission process, the corrugations concentrate the far-field radiated power within a tiny angular volume, offering unprecedented collection efficiency. In the past decades, many kinds of optical antennas have been proposed and optimized to enhance single molecule detection. However, the excitation enhancement effect for single individual or dimmer plasmonic nanostructure is limited due to intrinsic nonradiative decay of the nanoparticle plasmon and quantum tunneling effect. The proposed hybrid configuration overwhelms the enhancement limit of single individual plasmonic structure. The findings provide an insight into spontaneous emission high enhancement through integrating the functions of different metallic nanostructures.

A deep azygoesophageal recess may increase the risk of secondary spontaneous pneumothorax.

Science.gov (United States)

Takahashi, Tsuyoshi; Kawashima, Mitsuaki; Kuwano, Hideki; Nagayama, Kazuhiro; Nitadori, Jyunichi; Anraku, Masaki; Sato, Masaaki; Murakawa, Tomohiro; Nakajima, Jun

2017-09-01

The azygoesophageal recess (AER) is known as a possible cause of bulla formation in patients with spontaneous pneumothorax. However, there has been little focus on the depth of the AER. We evaluated the relationship between the depth of the AER and pneumothorax development. We conducted a retrospective study of 80 spontaneous pneumothorax patients who underwent surgery at our institution. We evaluated the depth of the AER on preoperative computed tomography scans. Ruptured bullae at the AER were found in 12 patients (52.2%) with secondary spontaneous pneumothorax (SSP) and 8 patients (14.0%) with primary spontaneous pneumothorax (PSP) (p < 0.001). In patients with ruptured bullae at the AER, 10 SSP patients (83.3%) had a deep AER while only 2 PSP patients (25%) had a deep AER (p = 0.015). A deep AER was more frequently associated with SSP than with PSP. A deep AER may contributes to bulla formation and rupture in SSP patients.

A thin line between Meniere’s disease and spontaneous intracranial hypotension syndrome

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Iva Botica

2016-02-01

Full Text Available Aim To point out the similarity of Meniere disease and spontaneous intracranial hypotension and difference of their treatment. Methods A case of a 54-year-old male patient with previously diagnosed Meniere’s disease and newly diagnosed spontaneous intracranial hypotension syndrome is presented. Additional neuroradiological examination, Brain contrast-enhanced MRI and MR myelography were used for diagnosis. Results Due to deterioration of vertigo, hearing loss and tinnitus in the right ear the patient was referred to the additional neuroradiological examination which confirmed the diagnosis of spontaneous intracranial hypotension syndrome. Brain contrast-enhanced MRI showed increased pachymeningeal contrast enhancement, and MR myelography identified the location of CSF leak. The patient was successfully treated conservatively. Conclusion According to our knowledge this is the fifth case report of Meniere’s disease and spontaneous intracranial hypotension coexistence. Both diseases have similar clinical presentation and initial treatment. We suggest procedures of additional examination when the treatment fails and initial diagnosis becomes questionable.

Spontaneous nystagmus in benign paroxysmal positional vertigo: is it a new sign?

Science.gov (United States)

Hajiabolhassan, Fahimeh; Tavanai, Elham

2013-01-01

Benign Paroxysmal Positional Vertigo (BPPV) is a condition that indicates a benign inner ear disorder. It is generally believed that BPPV is due to the dislodged otoconial particles from otolith organs and unusual collection of them within any of semicircular canals or even in all three semicircular canals. Although the typical features of nystagmus in BPPV have been well-studied, very few studies (just four articles) have highlighted the presence of spontaneous nystagmus in BPPV recently. During the past 10 years, 2850 patients have been examined at the audiology unit of our department, and 254 patients have received diagnoses of BPPV but recently 2 patients presented with BPPV and spontaneous nystagmus, a new symptom that has been never observed in our clinical records. We herein describe this rare symptom in 2 case of BPPV. A 50-year-old woman with BPPV who showed an 18 degree spontaneous nystagmus treated with Epley maneuver and a 53-year-old man with 3 degree spontaneous nystagmus.

The effect of pressure on spontaneous Rayleigh-Brillouin scattering spectrum in nitrogen

Science.gov (United States)

Yang, Chuanyin; Wu, Tao; Shang, Jingcheng; Zhang, Xinyi; Hu, Rongjing; He, XingDao

2018-05-01

In order to study the effect of gas pressure on spontaneous Rayleigh-Brillouin scattering spectrum and verify the validity of Tenti S6 model at pressures up to 8 atm, the spontaneous Rayleigh-Brillouin scattering experiment in nitrogen was performed for a wavelength of 532 nm at the constant room temperature of 296 K and a 90° scattering angle. By comparing the experimental spectrum with the theoretical spectrum, the normalized root mean square deviation was calculated and found less than 2.2%. It is verified that Tenti S6 model can be applied to the spontaneous Rayleigh-Brillion scattering of nitrogen under higher pressures. The results of the experimental data analysis demonstrate that pressure has more effect on Brillouin peak intensity and has negligible effect on Brillouin frequency shift, and pressure retrieval based on spontaneous Rayleigh-Brillouin scattering profile is a promising method for remote of pressure, such as harsh environment applications. Some factors that caused experiment deviations are also discussed.

Spontaneous subconjunctival abscess in congenital lamellar ichthyosis

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Shivanand C Bubanale

2018-01-01

Full Text Available Congenital lamellar ichthyosis is an autosomal recessive, heterogeneous disorder presenting at birth with generalized skin involvement. The most common ophthalmic manifestation noted is bilateral ectropion of the lower eyelids. A 1-month-old female neonate, the second born of a nonconsanguineous marriage, presented with 4 days' history of redness, discharge, and swelling in the right eye. There was severe right upper eyelid ectropion, conjunctival injection, chemosis, a subconjunctival mass on the temporal bulbar conjunctiva spontaneously draining pus and corneal haze. The anterior chamber, iris, lens and fundus appeared normal. Congenital lamellar ichthyosis was suspected because of scaling and excessive dryness of the entire body. The occurrence of a spontaneous subconjunctival abscess is not known in lamellar ichthyosis. We thus report the management of a rare case of unilateral upper eyelid ectropion, subconjunctival abscess with orbital cellulitis in congenital lamellar ichthyosis.

Grooming behavior of spontaneously hypertensive rats

NARCIS (Netherlands)

Buuse, M. van den; Jong, Wybren de

1987-01-01

In an open field spontaneously hypertensive rats (SHR) exhibited lower scores for grooming when compared to their normotensive controls, the Wistar Kyoto rats (WKY). After i.c.v. injection of 1 μg ACTH1–24 cumulative 50-min grooming scores were lower in SHR. Analysis of subscores indicated that the

Spontaneous burp phenomenon: analysis of experimental data and approach to theoretical interpretation

International Nuclear Information System (INIS)

Shabalin, E.

2004-01-01

Cases of spontaneous release of energy (''burp'') were observed numerously in solid methane, water ice and other hydrogeneous compounds irradiated in fast neutron fields with absorbed dose 2-10 MGy. Nature of this phenomenon is that accumulation of radicals and thermal instability of a sample under due concentration of radicals culminate to autocatalytic reaction of their recombination. The most odious feature of this phenomenon is that irradiation time, before a burp occurs, varies significantly even in identical irradiation condition. Respectively, amount of released energy varies as well. For example, in URAM-2 experiments with water ice, irradiation time before appearance of spontaneous burp varied from 5 hours to 11 hours for equal samples and up to 20 hours for the smallest sample. Another feature of the phenomenon is that regularities for occurrence of spontaneous release of energy (that is, dependence on temperature, size of sample, absorbed dose) can't be extracted explicitly from experimental data, if applying known relations for critical concentration of radicals, namely: Semenov's and Frank-Kamenetski's conditions of thermal instability of a sample, Jackson's relation for chain process of recombination of uniformly distributed radicals, critical condition based on accounting for acceleration of a process of recombination in the regions of micro-cracks, and, finally, critical condition for irregular distribution of radicals proposed by the author of this article. Not one of these theories predicts casual character of a burp on macro-scale basis. So that, notwithstanding fair amount of experimental data on spontaneous burps, it is still impossible to derive well-balanced theory of this phenomenon. One attempt to understand a reason for the strange behavior of spontaneous burping is a probabilistic, cluster model of spontaneous release of energy, developed in the chapter 4 of this paper. Spontaneous burps observed during URAM-2 project and in solid methane

Impairments of spontaneous and deliberative mentalizing co-occur, yet dissociate, in schizophrenia.

Science.gov (United States)

Langdon, Robyn; Flynn, Michaela; Connaughton, Emily; Brüne, Martin

2017-11-01

Evidence of impairment in explicit mentalizing in people with schizophrenia has inspired interventions to improve awareness of others' mental states in these individuals. Less is known of implicit mentalizing in schizophrenia, with current findings mixed. We sought to resolve previous inconsistencies using Heider & Simmel's (H&S) classic animation to elicit spontaneous mentalizing and examined relations between spontaneous and deliberative mentalizing. Forty-five schizophrenia outpatients and 27 general-community controls completed two explicit theory-of-mind (TOM) tasks and then described the H&S animation (to elicit spontaneous social attributions about emotionally driven, as well as goal-driven, behaviours), before and after an instruction to think of the shapes as people. Accuracy of basic and social facts and frequencies of personification and different mental-state terms were recorded. Explicit TOM performance was impaired in patients. Patients also generated fewer social (but not basic) facts than controls to describe the H&S animation, and used less mental-state language, before, and even more so, after the 'people' instruction, despite that both groups had used more personification terms after the 'people' instruction. Measures of explicit and spontaneous mentalizing contributed independently to discriminating between groups. Patients respond less to the bottom-up signals of agency that ought normally to elicit spontaneous social attributions, even when cued to think of the stimuli as people, and the stimuli depict emotionally driven, as well as goal-driven, behaviour. That impairments of spontaneous and deliberative mentalizing dissociate in schizophrenia suggests that training deliberative mentalizing may not be enough; interventions to improve spontaneous mentalizing are also needed. Findings People with schizophrenia were less likely than controls to spontaneously attribute causal mental states when viewing dynamic signals of emotionally driven and

Spontaneous disordering of a two-dimensional (2D) plasma crystal

International Nuclear Information System (INIS)

Zhdanov, Sergey K; Thoma, Markus H; Morfill, Gregor E

2011-01-01

Spontaneous disordering plays an important role in the physics of highly ordered complex plasmas. In this paper, an analytical theory is proposed for the process of 'cold amorphization', which has been observed. This consists of splitting a plasma crystal into sub-domains, followed by disordering. The results of recent simulations and experiments showing such spontaneous disordering have been reviewed and interpreted in this paper. Complex plasmas can serve as a powerful tool providing fundamental insight into this process generically.

Spontaneous grafting of diazonium salts: chemical mechanism on metallic surfaces.

Science.gov (United States)

Mesnage, Alice; Lefèvre, Xavier; Jégou, Pascale; Deniau, Guy; Palacin, Serge

2012-08-14

The spontaneous reaction of diazonium salts on various substrates has been widely employed since it consists of a simple immersion of the substrate in the diazonium salt solution. As electrochemical processes involving the same diazonium salts, the spontaneous grafting is assumed to give covalently poly(phenylene)-like bonded films. Resistance to solvents and to ultrasonication is commonly accepted as indirect proof of the existence of a covalent bond. However, the most relevant attempts to demonstrate a metal-C interface bond have been obtained by an XPS investigation of spontaneously grafted films on copper. Similarly, our experiments give evidence of such a bond in spontaneously grafted films on nickel substrates in acetonitrile. In the case of gold substrates, the formation of a spontaneous film was unexpected but reported in the literature in parallel to our observations. Even if no interfacial bond was observed, formation of the films was explained by grafting of aryl cations or radicals on the surface arising from dediazoniation, the film growing later by azo coupling, radical addition, or cationic addition on the grafted phenyl layer. Nevertheless, none of these mechanisms fits our experimental results showing the presence of an Au-N bond. In this work, we present a fine spectroscopic analysis of the coatings obtained on gold and nickel substrates that allow us to propose a chemical structure of such films, in particular, their interface with the substrates. After testing the most probable mechanisms, we have concluded in favor of the involvement of two complementary mechanisms which are the direct reaction of diazonium salts with the gold surface that accounts for the observed Au-N interfacial bonds as well as the formation of aryl cations able to graft on the substrate through Au-C linkages.

Rapid and spontaneous recovery in autistic disorder

OpenAIRE

Sitholey, Prabhat; Agarwal, Vivek; Pargaonkar, Amol

2009-01-01

Recovery in autistic disorder is rare. There are few reports of recovery from autistic disorder after a few years of therapeutic intervention. We report here a case of autistic disorder who recovered spontaneously without any intervention in 13 days.

Spontaneous long-range calcium waves in developing butterfly wings.

Science.gov (United States)

Ohno, Yoshikazu; Otaki, Joji M

2015-03-25

Butterfly wing color patterns emerge as the result of a regular arrangement of scales produced by epithelial scale cells at the pupal stage. These color patterns and scale arrangements are coordinated throughout the wing. However, the mechanism by which the development of scale cells is controlled across the entire wing remains elusive. In the present study, we used pupal wings of the blue pansy butterfly, Junonia orithya, which has distinct eyespots, to examine the possible involvement of Ca(2+) waves in wing development. Here, we demonstrate that the developing pupal wing tissue of the blue pansy butterfly displayed spontaneous low-frequency Ca(2+) waves in vivo that propagated slowly over long distances. Some waves appeared to be released from the immediate peripheries of the prospective eyespot and discal spot, though it was often difficult to identify the specific origins of these waves. Physical damage, which is known to induce ectopic eyespots, led to the radiation of Ca(2+) waves from the immediate periphery of the damaged site. Thapsigargin, which is a specific inhibitor of Ca(2+)-ATPases in the endoplasmic reticulum, induced an acute increase in cytoplasmic Ca(2+) levels and halted the spontaneous Ca(2+) waves. Additionally, thapsigargin-treated wings showed incomplete scale development as well as other scale and color pattern abnormalities. We identified a novel form of Ca(2+) waves, spontaneous low-frequency slow waves, which travel over exceptionally long distances. Our results suggest that spontaneous Ca(2+) waves play a critical role in the coordinated development of scale arrangements and possibly in color pattern formation in butterflies.

Selective Enhancement of Synaptic Inhibition by Hypocretin (Orexin) in Rat Vagal Motor Neurons: Implications for Autonomic Regulation

Science.gov (United States)

Davis, Scott F.; Williams, Kevin W.; Xu, Weiye; Glatzer, Nicholas R.; Smith, Bret N.

2012-01-01

The hypocretins (orexins) are hypothalamic neuropeptides implicated in feeding, arousal, and autonomic regulation. These studies were designed to determine the actions of hypocretin peptides on synaptic transmission in the dorsal motor nucleus of the vagus nerve (DMV). Whole-cell patch-clamp recordings were made from DMV neurons in transverse slices of rat brainstem. Some of the neurons were identified as gastric-related by retrograde labeling after inoculation of the stomach wall with pseudorabies virus 152, a viral label that reports enhanced green fluorescent protein. Consistent with previous findings, hypocretins caused an inward current (6–68 pA) in most neurons at holding potentials near rest. In addition, the frequency of spontaneous IPSCs was increased in a concentration-related manner (up to 477%), with little change in EPSCs. This effect was preserved in the presence of tetrodotoxin, suggesting a presynaptic site of action. Hypocretins increased the amplitude of IPSCs evoked by electrical stimulation of the nucleus tractus solitarius (NTS) but not evoked EPSCs. Hypocretin-induced increases in the frequency of IPSCs evoked by photoactivation of caged glutamate within the NTS were also observed. Identical effects of the peptides were observed in identified gastric-related and unlabeled DMV neurons. In contrast to some previous studies, which have reported primarily excitatory actions of the hypocretins in many regions of the CNS, these data support a role for hypocretin in preferentially enhancing synaptic inhibition, including inhibitory inputs arising from neurons in the NTS. These findings indicate that the hypocretins can modulate and coordinate visceral autonomic output by acting directly on central vagal circuits. PMID:12736355

Anaplastic Lymphoma Kinase Is a Regulator of Alcohol Consumption and Excitatory Synaptic Plasticity in the Nucleus Accumbens Shell

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Regina A. Mangieri

2017-08-01

Full Text Available Anaplastic lymphoma kinase (ALK is a receptor tyrosine kinase recently implicated in biochemical, physiological, and behavioral responses to ethanol. Thus, manipulation of ALK signaling may represent a novel approach to treating alcohol use disorder (AUD. Ethanol induces adaptations in glutamatergic synapses onto nucleus accumbens shell (NAcSh medium spiny neurons (MSNs, and putative targets for treating AUD may be validated for further development by assessing how their manipulation modulates accumbal glutamatergic synaptic transmission and plasticity. Here, we report that Alk knockout (AlkKO mice consumed greater doses of ethanol, relative to wild-type (AlkWT mice, in an operant self-administration model. Using ex vivo electrophysiology to examine excitatory synaptic transmission and plasticity at NAcSh MSNs that express dopamine D1 receptors (D1MSNs, we found that the amplitude of spontaneous excitatory post-synaptic currents (EPSCs in NAcSh D1MSNs was elevated in AlkKO mice and in the presence of an ALK inhibitor, TAE684. Furthermore, when ALK was absent or inhibited, glutamatergic synaptic plasticity – long-term depression of evoked EPSCs – in D1MSNs was attenuated. Thus, loss of ALK activity in mice is associated with elevated ethanol consumption and enhanced excitatory transmission in NAcSh D1MSNs. These findings add to the mounting evidence of a relationship between excitatory synaptic transmission onto NAcSh D1MSNs and ethanol consumption, point toward ALK as one important molecular mediator of this interaction, and further validate ALK as a target for therapeutic intervention in the treatment of AUD.

Noise-induced effects on multicellular biopacemaker spontaneous activity: Differences between weak and strong pacemaker cells

Science.gov (United States)

Aghighi, Alireza; Comtois, Philippe

2017-09-01

Self-organization of spontaneous activity of a network of active elements is important to the general theory of reaction-diffusion systems as well as for pacemaking activity to initiate beating of the heart. Monolayer cultures of neonatal rat ventricular myocytes, consisting of resting and pacemaker cells, exhibit spontaneous activation of their electrical activity. Similarly, one proposed approach to the development of biopacemakers as an alternative to electronic pacemakers for cardiac therapy is based on heterogeneous cardiac cells with resting and spontaneously beating phenotypes. However, the combined effect of pacemaker characteristics, density, and spatial distribution of the pacemaker cells on spontaneous activity is unknown. Using a simple stochastic pattern formation algorithm, we previously showed a clear nonlinear dependency of spontaneous activity (occurrence and amplitude of spontaneous period) on the spatial patterns of pacemaker cells. In this study, we show that this behavior is dependent on the pacemaker cell characteristics, with weaker pacemaker cells requiring higher density and larger clusters to sustain multicellular activity. These multicellular structures also demonstrated an increased sensitivity to voltage noise that favored spontaneous activity at lower density while increasing temporal variation in the period of activity. This information will help researchers overcome the current limitations of biopacemakers.

Cooperative spontaneous emission of nano-emitters with inter-emitter coupling in a leaky microcavity

International Nuclear Information System (INIS)

Hong, Suc-Kyoung; Nam, Seog Woo; Yang, Hyung Jin

2015-01-01

We study the spontaneous emission from a few two-level nano-emitters placed in a leaky microcavity with Lorentzian spectral density near a critically damped regime. Collective features of the spontaneous emission are investigated by numerical analysis of the excitation dynamics when initially one nano-emitter is totally excited but we do not know which one. The results show that there are three decay rates in the excitation dynamics, two for simple exponential decays and one for damped oscillatory decay. The excitation dynamics is found to critically depend on the regime of the system. It is shown that the spontaneous emission is enhanced or suppressed depending on whether the system is in the underdamped or overdamped regime, respectively. On the other hand, the cooperative spontaneous emission is suppressed in the underdamped while it is enhanced in the overdamped regime. Furthermore, the effect of the direct inter-emitter coupling on the breaking of the cooperativeness of the spontaneous emission is shown as well. (paper)

Top 100 Most-Cited Articles on Spontaneous Intracerebral Hemorrhage: A Bibliometric Analysis.

Science.gov (United States)

Nasir, Syed Ali Raza; Gilani, Jaleed Ahmed; Fatima, Kaneez; Faheem, Urooba; Kazmi, Omar; Siddiqi, Javed; Khosa, Faisal

2018-02-01

A bibliometric uses the citation count of an article to determine its impact on the clinical world. There is a paucity of literature concerning top article citations on spontaneous intracerebral hemorrhage (ICH). The main objective of this investigation was to bridge this gap and to provide understanding of the trends on the most influential articles written on this subject. The Scopus Library database was searched to determine the citations of all articles published on spontaneous ICH. Articles that focused on other forms of ICH, such as trauma-related hemorrhages, subarachnoid hemorrhages, or hemorrhages caused by anticoagulation, vascular malformations, or cavernomas, were excluded from our list. The articles were divided into 2 groups: "specific" articles, which focused specifically on spontaneous ICH, and "generalized" articles, which were about ICH in general, including spontaneous as well as other forms of ICH. We did not apply any time or study-type restriction in our search. The top 100 cited articles were selected and analyzed by 2 independent investigators. J. Broderick was the author with most publications in the list (n = 21). The largest subset of spontaneous ICH articles was published in the 5-year periods from 1996 to 2000 and 2001 to 2005 (n = 27 each). The United States had the highest number of articles (n = 49). The journal with the highest number of top 100 cited articles was Stroke, with 39, followed by Neurology with 16. Our study identifies the trends related to spontaneous ICH by analyzing the citation frequency of the most-cited articles in the field. Copyright © 2017 Elsevier Inc. All rights reserved.

Developing spontaneity and well-being in women victims of domestic violence

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Ines Testoni

2015-01-01

Full Text Available In this paper we present the results of the last stage of the research project Empower Daphne that involved the participation of six countries belonging to the EU in two phases: I validation of the theoretical model on which basis rests the construct of well-being and spontaneity; II analysis of Morenian psychodrama intervention efficacy. 407 university students were part of the non-clinical sample in the first phase and 136 women victims of domestic violence made up the clinical sample for the second phase. During the six month the women took part in psychodramatic sessions, together with individual interviews. At the beginning and the end of the six month, a questionnaire was administered consisting of a well-being and a spontaneity scales. In the article we present the results that compare well-being and spontaneity between clinical and non-clinical samples, and between the clinical cut-off scores highlighted in the literature and the scores of clinical sample. The findings demonstrate interesting differences between two sample: observed lower levels of spontaneity and well-being in women victims of domestic violence, both before and after the psychodramatic intervention.

Nontraumatic spontaneous rupture of the kidney : etiology and CT findings

International Nuclear Information System (INIS)

Heo, Tae Haeng; Jeon, Hae Jeong; Shin, Hyun Joon; Kim, Bo Hyun; Cho, Kyoung Sik; Kim, Young Hwa; Kim, Seung Hyup; Park, Churl Min

1997-01-01

To evaluate the usefulness of CT scanning in determining the etiology of spontaneous rupture of the kidney We retrospectively analyzed the CT findings of spontaneous rupture of the kidney in eleven patients, Four were male and seven were female, and they were aged between 20 and 71 (mean, 46.6) years. Both pre- and post-contrast enhanced CT scanning was performed in all patients. Spontaneous renal rupture was induced in seven cases by neoplasms (three angiomyolipomas, three renal cell carcinomas, and one metastatic choriocarcinoma), in three cases by infection or inflammation (acute and chronic pyelonephritis, and renal abscess), and in one, by renal cyst. Common CT findings of rupture of the kidney were the accumulation of high density fluid in the perirenal and anterior pararenal space, and inhomogeneous irregular low density of renal parenchyma and the rupture site. Angiomyolipoma showed fat and an angiomatous component in the lesion, while acute and chronic pyelonephrities revealed thinning of the renal parenchyma and an irregular renal outline. Renal cell carcinoma showed a dense soft tissue mass in the parenchyma. Well-defined, round low-density lesions were noted in the case of renal cyst and renal abscess. CT is very useful in diagnosing and determining the etiology of non-traumatic spontaneous rupture of the kidney and plays an important role in the evaluation of emergency cases

Spontaneous fungal peritonitis: Epidemiology, current evidence and future prospective.

Science.gov (United States)

Fiore, Marco; Leone, Sebastiano

2016-09-14

Spontaneous bacterial peritonitis is a complication of ascitic patients with end-stage liver disease (ESLD); spontaneous fungal peritonitis (SFP) is a complication of ESLD less known and described. ESLD is associated to immunodepression and the resulting increased susceptibility to infections. Recent perspectives of the management of the critically ill patient with ESLD do not specify the rate of isolation of fungi in critically ill patients, not even the antifungals used for the prophylaxis, neither optimal treatment. We reviewed, in order to focus the epidemiology, characteristics, and, considering the high mortality rate of SFP, the use of optimal empirical antifungal therapy the current literature.

Recurrent spontaneous intracerebral hemorrhage associated with ...

African Journals Online (AJOL)

Spontaneous intracerebral hemorrhage (ICH) accounts for 15% of stroke cases in the US and Europe and up to 30% in Asian populations. Intracerebral hemorrhage is a relatively uncommon form of stroke-it causes only 10 to 15 percent of all strokes. It is more disabling and has a higher mortality rate than ischemic stroke, ...

Fungal Peritonitis: Underestimated Disease in Critically Ill Patients with Liver Cirrhosis and Spontaneous Peritonitis.

Science.gov (United States)

Lahmer, Tobias; Brandl, Andreas; Rasch, Sebastian; Schmid, Roland M; Huber, Wolfgang

2016-01-01

Spontaneous peritonitis, especially spontaneous fungal peritonitis (SFP), is an important and potentially fatal complication in patients with endstage liver disaese. We evaluated potential risk factors, microbiological findings, and outcome of patients with SFP compared to spontaneous bacterial peritonitis (SBP) in critically ill patients. Retrospective analyses of critically ill patients with suspected spontaneous peritonitis. Out of 205 patients, 20 (10%) had SFP, 28 (14%) had SBP, 48 (24%) had peritonitis without microbiological findings (SP) and 109 (52%) had no-peritonitis (NP). APACHE II and SOFA score were significantly higher in patients with SFP (26; 22-28; pperitonitis could be significantly more often found in patients with SFP (65%; pperitonitis was significantly more often in patients with SFP (85%; pperitonitis.

Development of a prognostic model for predicting spontaneous singleton preterm birth.

Science.gov (United States)

Schaaf, Jelle M; Ravelli, Anita C J; Mol, Ben Willem J; Abu-Hanna, Ameen

2012-10-01

To develop and validate a prognostic model for prediction of spontaneous preterm birth. Prospective cohort study using data of the nationwide perinatal registry in The Netherlands. We studied 1,524,058 singleton pregnancies between 1999 and 2007. We developed a multiple logistic regression model to estimate the risk of spontaneous preterm birth based on maternal and pregnancy characteristics. We used bootstrapping techniques to internally validate our model. Discrimination (AUC), accuracy (Brier score) and calibration (calibration graphs and Hosmer-Lemeshow C-statistic) were used to assess the model's predictive performance. Our primary outcome measure was spontaneous preterm birth at model included 13 variables for predicting preterm birth. The predicted probabilities ranged from 0.01 to 0.71 (IQR 0.02-0.04). The model had an area under the receiver operator characteristic curve (AUC) of 0.63 (95% CI 0.63-0.63), the Brier score was 0.04 (95% CI 0.04-0.04) and the Hosmer Lemeshow C-statistic was significant (pvalues of predicted probability. The positive predictive value was 26% (95% CI 20-33%) for the 0.4 probability cut-off point. The model's discrimination was fair and it had modest calibration. Previous preterm birth, drug abuse and vaginal bleeding in the first half of pregnancy were the most important predictors for spontaneous preterm birth. Although not applicable in clinical practice yet, this model is a next step towards early prediction of spontaneous preterm birth that enables caregivers to start preventive therapy in women at higher risk. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Spontaneous regression of intracranial malignant lymphoma

International Nuclear Information System (INIS)

Kojo, Nobuto; Tokutomi, Takashi; Eguchi, Gihachirou; Takagi, Shigeyuki; Matsumoto, Tomie; Sasaguri, Yasuyuki; Shigemori, Minoru.

1988-01-01

In a 46-year-old female with a 1-month history of gait and speech disturbances, computed tomography (CT) demonstrated mass lesions of slightly high density in the left basal ganglia and left frontal lobe. The lesions were markedly enhanced by contrast medium. The patient received no specific treatment, but her clinical manifestations gradually abated and the lesions decreased in size. Five months after her initial examination, the lesions were absent on CT scans; only a small area of low density remained. Residual clinical symptoms included mild right hemiparesis and aphasia. After 14 months the patient again deteriorated, and a CT scan revealed mass lesions in the right frontal lobe and the pons. However, no enhancement was observed in the previously affected regions. A biopsy revealed malignant lymphoma. Despite treatment with steroids and radiation, the patient's clinical status progressively worsened and she died 27 months after initial presentation. Seven other cases of spontaneous regression of primary malignant lymphoma have been reported. In this case, the mechanism of the spontaneous regression was not clear, but changes in immunologic status may have been involved. (author)

Spontaneous wound dehiscence after penetrating keratoplasty

Directory of Open Access Journals (Sweden)

Alireza Foroutan

2014-10-01

Full Text Available Spontaneous wound separation may be developed even months after suture removal especially in the context of long-term corticosteroid therapy. A 68-year-old Caucasian woman presented to our cornea clinic with spontaneous wound dehiscence after her third penetrating keratoplasty (PKP which was performed three years ago. An Ahmed glaucoma valve (New World Medical, Ranchos Cucamonga, CA was inserted ten months after the third PKP, which successfully controlled intraocular pressure (IOP. At the examination, the last sutures were removed eight months ago and she was using flourometholone 0.1 % (Sina Darou, Tehran, Iran with a dose of once a day. There was one quadrant of wound dehiscence from 8 to 11 o`clock associated with anterior wound gape and severe corneal edema. Resuturing was performed for the patient. At the one month examination, the corneal edema was resolved and best corrected visual acuity was 20/200 mainly due to previous glaucomatous optic neuropathy. Caution about the prolonged use of corticosteroids is necessary. Topical immunosuppressives could be a promising choice in this field.

Progesterone to prevent spontaneous preterm birth

Science.gov (United States)

Romero, Roberto; Yeo, Lami; Chaemsaithong, Piya; Chaiworapongsa, Tinnakorn; Hassan, Sonia

2014-01-01

Summary Preterm birth is the leading cause of perinatal morbidity and mortality worldwide, and its prevention is an important healthcare priority. Preterm parturition is one of the ‘great obstetrical syndromes’ and is caused by multiple etiologies. One of the mechanisms of disease is the untimely decline in progesterone action, which can be manifested by a sonographic short cervix in the midtrimester. The detection of a short cervix in the midtrimester is a powerful risk factor for preterm delivery. Vaginal progesterone can reduce the rate of preterm delivery by 45%, and the rate of neonatal morbidity (admission to neonatal intensive care unit, respiratory distress syndrome, need for mechanical ventilation, etc.). To prevent one case of spontaneous preterm birth birth in women with a short cervix both with and without a prior history of preterm birth. In patients with a prior history of preterm birth, vaginal progesterone is as effective as cervical cerclage to prevent preterm delivery. 17α-Hydroxyprogesterone caproate has not been shown to be effective in reducing the rate of spontaneous preterm birth in women with a short cervix. PMID:24315687

Echocardiographic Follow-Up of Patent Foramen Ovale and the Factors Affecting Spontaneous Closure.

Science.gov (United States)

Yildirim, Ali; Aydin, Alperen; Demir, Tevfik; Aydin, Fatma; Ucar, Birsen; Kilic, Zubeyir

2016-11-01

The aim of the present study was to evaluate the echocardiographic follow-up of patent foramen ovale, which is considered a potential etiological factor in various diseases, and to determine the factors affecting spontaneous closure. Between January 2000 and June 2012, records of 918 patients with patent foramen ovale were retrospectively reviewed. Patency of less than 3 mm around the fossa ovalis is called patent foramen ovale. Patients with cyanotic congenital heart diseases, severe heart valve disorders and severe hemodynamic left to right shunts were excluded from the study. The patients were divided into three groups based on age; 1 day-1 month in group 1, 1 month-12 months in group 2, and more than 12 months in group 3. Of the 918 patients, 564 (61.4%) had spontaneous closure, 328 (35.8%) had patent foramen ovale continued, 15 (1.6%) patients had patent foramen ovale enlarged to 3-5 mm, 6 patients were enlarged to 5-8 mm, and in one patient patent foramen ovale reached to more than 8 mm size. Defect was spontaneously closed in 65.9% of the patients in group 1, 66.7% of the patients in group 2, and 52.3% of the patients in group 3. There was a negative correlation between the age of diagnosis and spontaneous closure (p patent ductus arteriosus and atrial septal aneurysm did not have any effect on spontaneous closure of patent foramen ovale (p > 0.05). However, ventricular septal defect and spontaneous closure of patent foramen ovale had a positive correlation (p closure rate of patent foramen ovale is high. Furthermore, a positive correlation was found between spontaneous closure of patent foramen ovale with early diagnosis and small defect size.

Lack of causal association between spontaneous intracranial hypotension and cranial cerebrospinal fluid leaks.

Science.gov (United States)

Schievink, Wouter I; Schwartz, Marc S; Maya, M Marcel; Moser, Franklin G; Rozen, Todd D

2012-04-01

Spontaneous intracranial hypotension is an important cause of headaches and an underlying spinal CSF leak can be demonstrated in most patients. Whether CSF leaks at the level of the skull base can cause spontaneous intracranial hypotension remains a matter of controversy. The authors' aim was to examine the frequency of skull base CSF leaks as the cause of spontaneous intracranial hypotension. Demographic, clinical, and radiological data were collected from a consecutive group of patients evaluated for spontaneous intracranial hypotension during a 9-year period. Among 273 patients who met the diagnostic criteria for spontaneous intracranial hypotension and 42 who did not, not a single instance of CSF leak at the skull base was encountered. Clear nasal drainage was reported by 41 patients, but a diagnosis of CSF rhinorrhea could not be established. Four patients underwent exploratory surgery for presumed CSF rhinorrhea. In addition, the authors treated 3 patients who had a postoperative CSF leak at the skull base following the resection of a cerebellopontine angle tumor and developed orthostatic headaches; spinal imaging, however, demonstrated the presence of a spinal source of CSF leakage in all 3 patients. There is no evidence for an association between spontaneous intracranial hypotension and CSF leaks at the level of the skull base. Moreover, the authors' study suggests that a spinal source for CSF leakage should even be suspected in patients with orthostatic headaches who have a documented skull base CSF leak.

Controlling spontaneous emission dynamics in semiconductor micro cavities

Science.gov (United States)

Gayral, B.

Spontaneous emission of light can be controlled, cavity quantum electrodynamics tells us, and many experiments in atomic physics demonstrated this fact. In particular, coupling an emitter to a resonant photon mode of a cavity can enhance its spontaneous emission rate: this is the so-called Purcell effect. Though appealing it might seem to implement these concepts for the benefit of light-emitting semiconductor devices, great care has to be taken as to which emitter/cavity system should be used. Semiconductor quantum boxes prove to be good candidates for witnessing the Purcell effect. Also, low volume cavities having a high optical quality in other words a long photon storage time are required. State-of-the-art fabrication techniques of such cavities are presented and discussed.We demonstrate spontaneous emission rate enhancement for InAs/GaAs quantum boxes in time-resolved and continuous-wave photoluminescence experiments. This is done for two kinds of cavities, namely GaAs/AlAs micropillars (global enhancement by a factor of 5), and GaAs microdisks (global enhancement by a factor of 20). Prospects for lasers, light-emitting diodes and single photon sources based on the Purcell effect are discussed. L'émission spontanée de lumière peut être contrôlée, ainsi que nous l'enseigne l'électrodynamique quantique en cavité, ce fait a été démontré expérimentalement en physique atomique. En particulier, coupler un émetteur à un mode photonique résonnant d'une cavité peut exalter son taux d'émission spontanée : c'est l'effet Purcell. Bien qu'il semble très prometteur de mettre en pratique ces concepts pour améliorer les dispositifs semi-conducteurs émetteurs de lumière, le choix du système émetteur/cavité est crucial. Nous montrons que les boîtes quantiques semi-conductrices sont des bons candidats pour observer l'effet Purcell. Il faut par ailleurs des cavités de faible volume ayant une grande qualité optique en d'autres mots un long temps de

Particle-in-cell simulations on spontaneous thermal magnetic field fluctuations

Energy Technology Data Exchange (ETDEWEB)

Simões, F. J. R. Jr.; Pavan, J. [Instituto de Física e Matemática, UFPel, Pelotas, RS (Brazil); Gaelzer, R.; Ziebell, L. F. [Instituto de Física, UFRGS, Porto Alegre, RS (Brazil); Yoon, P. H. [Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742 (United States)

2013-10-15

In this paper an electromagnetic particle code is used to investigate the spontaneous thermal emission. Specifically we perform particle-in-cell simulations employing a non-relativistic isotropic Maxwellian particle distribution to show that thermal fluctuations are related to the origin of spontaneous magnetic field fluctuation. These thermal fluctuations can become seed for further amplification mechanisms and thus be considered at the origin of the cosmological magnetic field, at microgauss levels. Our numerical results are in accordance with theoretical results presented in the literature.

Tapping Into Rate Flexibility: Musical Training Facilitates Synchronization Around Spontaneous Production Rates

Science.gov (United States)

Scheurich, Rebecca; Zamm, Anna; Palmer, Caroline

2018-01-01

The ability to flexibly adapt one’s behavior is critical for social tasks such as speech and music performance, in which individuals must coordinate the timing of their actions with others. Natural movement frequencies, also called spontaneous rates, constrain synchronization accuracy between partners during duet music performance, whereas musical training enhances synchronization accuracy. We investigated the combined influences of these factors on the flexibility with which individuals can synchronize their actions with sequences at different rates. First, we developed a novel musical task capable of measuring spontaneous rates in both musicians and non-musicians in which participants tapped the rhythm of a familiar melody while hearing the corresponding melody tones. The novel task was validated by similar measures of spontaneous rates generated by piano performance and by the tapping task from the same pianists. We then implemented the novel task with musicians and non-musicians as they synchronized tapping of a familiar melody with a metronome at their spontaneous rates, and at rates proportionally slower and faster than their spontaneous rates. Musicians synchronized more flexibly across rates than non-musicians, indicated by greater synchronization accuracy. Additionally, musicians showed greater engagement of error correction mechanisms than non-musicians. Finally, differences in flexibility were characterized by more recurrent (repetitive) and patterned synchronization in non-musicians, indicative of greater temporal rigidity. PMID:29681872

Tapping Into Rate Flexibility: Musical Training Facilitates Synchronization Around Spontaneous Production Rates

Directory of Open Access Journals (Sweden)

Rebecca Scheurich

2018-04-01

Full Text Available The ability to flexibly adapt one’s behavior is critical for social tasks such as speech and music performance, in which individuals must coordinate the timing of their actions with others. Natural movement frequencies, also called spontaneous rates, constrain synchronization accuracy between partners during duet music performance, whereas musical training enhances synchronization accuracy. We investigated the combined influences of these factors on the flexibility with which individuals can synchronize their actions with sequences at different rates. First, we developed a novel musical task capable of measuring spontaneous rates in both musicians and non-musicians in which participants tapped the rhythm of a familiar melody while hearing the corresponding melody tones. The novel task was validated by similar measures of spontaneous rates generated by piano performance and by the tapping task from the same pianists. We then implemented the novel task with musicians and non-musicians as they synchronized tapping of a familiar melody with a metronome at their spontaneous rates, and at rates proportionally slower and faster than their spontaneous rates. Musicians synchronized more flexibly across rates than non-musicians, indicated by greater synchronization accuracy. Additionally, musicians showed greater engagement of error correction mechanisms than non-musicians. Finally, differences in flexibility were characterized by more recurrent (repetitive and patterned synchronization in non-musicians, indicative of greater temporal rigidity.

Cooling Effect Analysis of Suppressing Coal Spontaneous Ignition with Heat Pipe

Science.gov (United States)

Zhang, Yaping; Zhang, Shuanwei; Wang, Jianguo; Hao, Gaihong

2018-05-01

Suppression of spontaneous ignition of coal stockpiles was an important issue for safe utilization of coal. The large thermal energy from coal spontaneous ignition can be viewed as the latent energy source to further utilize for saving energy purpose. Heat pipe was the more promising way to diffuse effectively concentrated energy of the coal stockpile, so that retarding coal spontaneous combustion was therefore highly desirable. The cooling mechanism of the coal with heat pipe was pursued. Based on the research result, the thermal energy can be transported from the coal seam to the surface continuously with the use of heat pipe. Once installed the heat pipes will work automatically as long as the coal oxidation reaction was happened. The experiment was indicated that it can significantly spread the high temperature of the coal pile.

Spontaneous conversion of first onset atrial fibrillation

DEFF Research Database (Denmark)

Lindberg, Søren Østergaard; Hansen, Sidsel; Nielsen, Tonny

2011-01-01

Background  We studied all patients admitted to hospital with first onset atrial fibrillation (AF) to determine the probability of spontaneous conversion to sinus rhythm and to identify factors predictive of such a conversion. Methods and Results  We retrospectively reviewed charts of 438...

Spontaneously broken version of N=4 supersymmetry

International Nuclear Information System (INIS)

Terent'ev, M.V.

1989-01-01

The special scenario of reduction from the space of D=10 dimensions is used to construct the theory with describes interaction of supergravity with only one multiplet of matter in the framework of spontaneously broken N=4 supersymmetry. 6 refs.; 1 fig

Maternal Factors Associated With Early Spontaneous Singleton ...

African Journals Online (AJOL)

Background: Knowledge of the maternal factors predisposing to preterm deliveries should affect the anticipatory care of mothers at risk of delivering preterm babies and improve perinatal outcome. Objective: To determine the maternal socio-biological characteristics associated with the delivery of early spontaneous ...

Unified gauge theories with spontaneous symmetry breaking

International Nuclear Information System (INIS)

MacDowell, S.W.

1975-01-01

Unified gauge theories with spontaneous symmetry breaking are studied with a view to renormalize quantum field theory. Georgi-Glashow and Weinberg-Salam models to unify weak and electromagnetic interactions are discussed in detail. Gauge theories of strong interactions are also considered [pt

Spontaneous Non-verbal Counting in Toddlers

Science.gov (United States)

Sella, Francesco; Berteletti, Ilaria; Lucangeli, Daniela; Zorzi, Marco

2016-01-01

A wealth of studies have investigated numerical abilities in infants and in children aged 3 or above, but research on pre-counting toddlers is sparse. Here we devised a novel version of an imitation task that was previously used to assess spontaneous focusing on numerosity (i.e. the predisposition to grasp numerical properties of the environment)…

Spontaneous extracranial decompression of epidural hematoma

International Nuclear Information System (INIS)

Neely, John C.; Jones, Blaise V.; Crone, Kerry R.

2008-01-01

Epidural hematoma (EDH) is a common sequela of head trauma in children. An increasing number are managed nonsurgically, with close clinical and imaging observation. We report the case of a traumatic EDH that spontaneously decompressed into the subgaleal space, demonstrated on serial CT scans that showed resolution of the EDH and concurrent enlargement of the subgaleal hematoma. (orig.)

Spontaneous extracranial decompression of epidural hematoma

Energy Technology Data Exchange (ETDEWEB)

Neely, John C. [Marshall University School of Medicine, Huntington, WV (United States); Jones, Blaise V. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Crone, Kerry R. [Cincinnati Children' s Hospital Medical Center, Division of Neurosurgery, Cincinnati, OH (United States)

2008-03-15

Epidural hematoma (EDH) is a common sequela of head trauma in children. An increasing number are managed nonsurgically, with close clinical and imaging observation. We report the case of a traumatic EDH that spontaneously decompressed into the subgaleal space, demonstrated on serial CT scans that showed resolution of the EDH and concurrent enlargement of the subgaleal hematoma. (orig.)

Being Spontaneous: The Future of Telehealth Implementation?

Science.gov (United States)

Mars, Maurice; Scott, Richard E

2017-09-01

The smartphone simplifies interprofessional communication, and smartphone applications can facilitate telemedicine activity. Much has been written about the steps that need to be followed to implement and establish a successful telemedicine service that is integrated into everyday clinical practice. A traditional and systematic approach has evolved incorporating activities such as strategy development, needs assessment, business cases and plans, readiness assessment, implementation plans, change management interventions, and ongoing monitoring and evaluation. This "best practice" has been promoted in the telehealth literature for many years. In contrast, several recent initiatives have arisen without any such formal undertakings. This article describes the strengths and weaknesses of two "spontaneous" telemedicine services in dermatology and burn management that have evolved in South Africa. Two spontaneous services were identified and reviewed. In one unsolicited service, doctors at rural referring hospitals have been taking photographs of skin lesions and sending them with a brief text message history to dermatologists using the instant messaging smartphone app, WhatsApp. In the other, burns service, admissions to the burns unit or the clinic were triaged by telephonic description of the case and completion of a preadmission questionnaire. More recently, management and referral decisions are made only after completion of the questionnaire and subsequent submission of photographs of the burn sent by WhatsApp, with the decision transmitted by text message. Although efficient and effective, potential legal and ethical shortcomings have been identified. These "spontaneous" telehealth services challenge traditional best practice, yet appear to lead to truly integrated practice and, therefore, are successful and warrant further study.

Assessment of Relationship between Spontaneous Abortion and Occupational Exposure to Organic Solvents

Directory of Open Access Journals (Sweden)

S Mohammadi

2011-04-01

Full Text Available Introduction & Objective: Nowadays, some studies indicate the adverse effects of exposure to chemicals, especially organic solvents on the reproductive system of females. This study aimed to assess the relationship between spontaneous abortion with occupational exposure to organic solvents in pharmaceutical industry. Materials & Methods: This is a cross-sectional and descriptive-analytical study which was carried out in 2010 in one of the pharmaceutical factories located in the suburbs of Tehran. During the study, married women who were working in the factory laboratory units and were exposed to mixed organic solvents were compared with married women who were working in the packing units of the factory without occupational exposure to organic solvents. Frequency of spontaneous abortion and duration of pregnancy were assessed in both two groups. Collected data were analyzed with the SPSS software using t-test, logistic regression, and chi-square test. Results: In the present study, the frequency of spontaneous abortion in employees with exposure to organic solvents mixture was 10.7%. This study showed that even after adjustment for confounding factors, there was a significant correlation between spontaneous abortion and occupational exposure to organic solvents mixture and this correlation increased with increasing levels of exposure to organic solvents. Moreover, a significant correlation was observed between occupational exposure to mixed organic solvents and waiting time to become pregnant (TTP. Furthermore, this study showed that even after adjustment for confounding variables, shift workers were significantly more affected by spontaneous abortion compared to daytime workers (P < 0.001. Conclusion: According to the results of this study, since there is probability of spontaneous abortion resulting from occupational exposure to various chemicals including organic solvents, review of the status of occupational exposure of workers can be helpful

Laser-induced electron--ion recombination used to study enhanced spontaneous recombination during electron cooling

International Nuclear Information System (INIS)

Schramm, U.; Wolf, A.; Schuess ler, T.; Habs, D.; Schwalm, D.; Uwira, O.; Linkemann, J.; Mueller, A.

1997-01-01

Spontaneous recombination of highly charged ions with free electrons in merged velocity matched electron and ion beams has been observed in earlier experiments to occur at rates significantly higher than predicted by theoretical estimates. To study this enhanced spontaneous recombination, laser induced recombination spectra were measured both in velocity matched beams and in beams with well defined relative velocities, corresponding to relative electron-ion detuning energies ranging from 1 meV up to 6.5 meV where the spontaneous recombination enhancement was found to be strongly reduced. Based on a comparison with simplified calculations, the development of the recombination spectra for decreasing detuning energies indicates additional contributions at matched velocities which could be related to the energy distribution of electrons causing the spontaneous recombination rate enhancement

Spontaneous emission of quantum dots in disordered photonic crystal waveguides

DEFF Research Database (Denmark)

Sapienza, Luca; Nielsen, Henri Thyrrestrup; Stobbe, Søren

2010-01-01

We report on the enhancement of the spontaneous emission rate of single semiconductor quantum dots embedded in a photonic crystal waveguide with engineered disorder. Random high-Q cavities, that are signature of Anderson localization, are measured in photoluminescence experiments and appear...... in the slow light regime of the waveguide mode. Time resolved experiments show a 15-fold enhancement of the spontaneous emission rate, with coupling efficiencies of single photons into Anderson localized cavity modes of 94%. These results show that the performances of Anderson-localized cavities...

Experimental anti-GBM disease as a tool for studying spontaneous lupus nephritis.

Science.gov (United States)

Fu, Yuyang; Du, Yong; Mohan, Chandra

2007-08-01

Lupus nephritis is an immune-mediated disease, where antibodies and T cells both play pathogenic roles. Since spontaneous lupus nephritis in mouse models takes 6-12 months to manifest, there is an urgent need for a mouse model that can be used to delineate the pathogenic processes that lead to immune nephritis, over a quicker time frame. We propose that the experimental anti-glomerular basement membrane (GBM) disease model might be a suitable tool for uncovering some of the molecular steps underlying lupus nephritis. This article reviews the current evidence that supports the use of the experimental anti-GBM nephritis model for studying spontaneous lupus nephritis. Importantly, out of about 25 different molecules that have been specifically examined in the experimental anti-GBM model and also spontaneous lupus nephritis, all influence both diseases concordantly, suggesting that the experimental model might be a useful tool for unraveling the molecular basis of spontaneous lupus nephritis. This has important clinical implications, both from the perspective of genetic susceptibility as well as clinical therapeutics.

Spatial Memory in Spontaneously Hypertensive Rats (SHR)

NARCIS (Netherlands)

Sontag, Thomas-A.; Fuermaier, Anselm B. M.; Hauser, Joachim; Kaunzinger, Ivo; Tucha, Oliver; Lange, Klaus W.

2013-01-01

The spontaneously hypertensive rat (SHR) is an established animal model of ADHD. It has been suggested that ADHD symptoms arise from deficits in executive functions such as working memory, attentional control and decision making. Both ADHD patients and SHRs show deficits in spatial working memory.

Influence of spontaneous fermentation on some quality ...

African Journals Online (AJOL)

Sensory evaluation indicated that the techniques of nixtamalization, fermentation and cowpea fortification used for the processing of the products did not influence their acceptability by the panel. Nixtamalized maize can therefore be subjected to spontaneous fermentation with cowpea fortification to enhance the functional, ...

No Evidence for Spontaneous Lipid Transfer at ER-PM Membrane Contact Sites.

Science.gov (United States)

Merklinger, Elisa; Schloetel, Jan-Gero; Spitta, Luis; Thiele, Christoph; Lang, Thorsten

2016-04-01

Non-vesicular lipid transport steps play a crucial role in lipid trafficking and potentially include spontaneous exchange. Since membrane contact facilitates this lipid transfer, it is most likely to occur at membrane contact sites (MCS). However, to date it is unknown whether closely attached biological membranes exchange lipids spontaneously. We have set up a system for studying the exchange of lipids at MCS formed between the endoplasmic reticulum (ER) and the plasma membrane. Contact sites were stably anchored and the lipids cholesterol and phosphatidylcholine (PC) were not capable of transferring spontaneously into the opposed bilayer. We conclude that physical contact between two associated biological membranes is not sufficient for transfer of the lipids PC and cholesterol.

Coherent manipulation of spontaneous emission spectra in coupled semiconductor quantum well structures.

Science.gov (United States)

Chen, Aixi

2014-11-03

In triple coupled semiconductor quantum well structures (SQWs) interacting with a coherent driving filed, a coherent coupling field and a weak probe field, spontaneous emission spectra are investigated. Our studies show emission spectra can easily be manipulated through changing the intensity of the driving and coupling field, detuning of the driving field. Some interesting physical phenomena such as spectral-line enhancement/suppression, spectral-line narrowing and spontaneous emission quenching may be obtained in our system. The theoretical studies of spontaneous emission spectra in SQWS have potential application in high-precision spectroscopy. Our studies are based on the real physical system [Appl. Phys. Lett.86(20), 201112 (2005)], and this scheme might be realizable with presently available techniques.

Sensory memory for odors is encoded in spontaneous correlated activity between olfactory glomeruli.

Science.gov (United States)

Galán, Roberto F; Weidert, Marcel; Menzel, Randolf; Herz, Andreas V M; Galizia, C Giovanni

2006-01-01

Sensory memory is a short-lived persistence of a sensory stimulus in the nervous system, such as iconic memory in the visual system. However, little is known about the mechanisms underlying olfactory sensory memory. We have therefore analyzed the effect of odor stimuli on the first odor-processing network in the honeybee brain, the antennal lobe, which corresponds to the vertebrate olfactory bulb. We stained output neurons with a calcium-sensitive dye and measured across-glomerular patterns of spontaneous activity before and after a stimulus. Such a single-odor presentation changed the relative timing of spontaneous activity across glomeruli in accordance with Hebb's theory of learning. Moreover, during the first few minutes after odor presentation, correlations between the spontaneous activity fluctuations suffice to reconstruct the stimulus. As spontaneous activity is ubiquitous in the brain, modifiable fluctuations could provide an ideal substrate for Hebbian reverberations and sensory memory in other neural systems.

Spontaneous Recovery After Extinction of the Conditioned Proboscis Extension Response in the Honeybee

Science.gov (United States)

Sandoz, Jean-Christophe; Pham-Delègue, Minh-Hà

2004-01-01

In honeybees, the proboscis extension response (PER) can be conditioned by associating an odor stimulus (CS) to a sucrose reward (US). Conditioned responses to the CS, which are acquired by most bees after a single CS-US pairing, disappear after repeated unrewarded presentations of the CS, a process called extinction. Extinction is usually thought to be based either on (1) the disruption of the stored CS-US association, or (2) the formation of an inhibitory “CS-no US” association that is better retrieved than the initial CS-US association. The observation of spontaneous recovery, i.e., the reappearance of responses to the CS after time passes following extinction, is traditionally interpreted as a proof for the formation of a transient inhibitory association. To provide a better understanding of extinction in honeybees, we examined whether time intervals during training and extinction or the number of conditioning and extinction trials have an effect on the occurrence of spontaneous recovery. We found that spontaneous recovery mostly occurs when conditioning and testing took place in a massed fashion (1-min intertrial intervals). Moreover, spontaneous recovery depended on the time elapsed since extinction, 1 h being an optimum. Increasing the number of conditioning trials improved the spontaneous recovery level, whereas increasing the number of extinction trials reduced it. Lastly, we show that after single-trial conditioning, spontaneous recovery appears only once after extinction. These elements suggest that in honeybees extinction of the PER actually reflects the impairment of the CS-US association, but that depending on training parameters different memory substrates are affected. PMID:15466313

Spontaneous swallow frequency compared with clinical screening in the identification of dysphagia in acute stroke.

Science.gov (United States)

Crary, Michael A; Carnaby, Giselle D; Sia, Isaac

2014-09-01

The aim of this study was to compare spontaneous swallow frequency analysis (SFA) with clinical screening protocols for identification of dysphagia in acute stroke. In all, 62 patients with acute stroke were evaluated for spontaneous swallow frequency rates using a validated acoustic analysis technique. Independent of SFA, these same patients received a routine nurse-administered clinical dysphagia screening as part of standard stroke care. Both screening tools were compared against a validated clinical assessment of dysphagia for acute stroke. In addition, psychometric properties of SFA were compared against published, validated clinical screening protocols. Spontaneous SFA differentiates patients with versus without dysphagia after acute stroke. Using a previously identified cut point based on swallows per minute, spontaneous SFA demonstrated superior ability to identify dysphagia cases compared with a nurse-administered clinical screening tool. In addition, spontaneous SFA demonstrated equal or superior psychometric properties to 4 validated, published clinical dysphagia screening tools. Spontaneous SFA has high potential to identify dysphagia in acute stroke with psychometric properties equal or superior to clinical screening protocols. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Spontaneous and visually-driven high-frequency oscillations in the occipital cortex: Intracranial recording in epileptic patients

Science.gov (United States)

Nagasawa, Tetsuro; Juhász, Csaba; Rothermel, Robert; Hoechstetter, Karsten; Sood, Sandeep; Asano, Eishi

2011-01-01

SUMMARY High-frequency oscillations (HFOs) at ≧80 Hz of nonepileptic nature spontaneously emerge from human cerebral cortex. In 10 patients with extra-occipital lobe epilepsy, we compared the spectral-spatial characteristics of HFOs spontaneously arising from the nonepileptic occipital cortex with those of HFOs driven by a visual task as well as epileptogenic HFOs arising from the extra-occipital seizure focus. We identified spontaneous HFOs at ≧80 Hz with a mean duration of 330 msec intermittently emerging from the occipital cortex during interictal slow-wave sleep. The spectral frequency band of spontaneous occipital HFOs was similar to that of visually-driven HFOs. Spontaneous occipital HFOs were spatially sparse and confined to smaller areas, whereas visually-driven HFOs involved the larger areas including the more rostral sites. Neither spectral frequency band nor amplitude of spontaneous occipital HFOs significantly differed from those of epileptogenic HFOs. Spontaneous occipital HFOs were strongly locked to the phase of delta activity, but the strength of delta-phase coupling decayed from 1 to 3 Hz. Conversely, epileptogenic extra-occipital HFOs were locked to the phase of delta activity about equally in the range from 1 to 3 Hz. The occipital cortex spontaneously generates physiological HFOs which may stand out on electrocorticography traces as prominently as pathological HFOs arising from elsewhere; this observation should be taken into consideration during presurgical evaluation. Coupling of spontaneous delta and HFOs may increase the understanding of significance of delta-oscillations during slow-wave sleep. Further studies are warranted to determine whether delta-phase coupling distinguishes physiological from pathological HFOs or simply differs across anatomical locations. PMID:21432945

Diuretic Action of Exogenous Hydrogen Sulfide in Spontaneously ...

African Journals Online (AJOL)

HP

Keywords: Spontaneously hypertensive rats, Diabetes, Hydrogen sulphide, Diuretic, Sodium excretion,. Urine output ... molecule H2S can be generated in many types of mammalian .... 96-well plate reader (Bio-Tek instruments, INC,. USA).

Bacterial vaginosis in association with spontaneous abortion and recurrent pregnancy losses

Directory of Open Access Journals (Sweden)

Gözde Isik

2016-01-01

Full Text Available Context: Bacterial vaginosis (BV is related to the increased risk of miscarriage, preterm labor, and postpartum endometritis. Aims: The aim of this study was to evaluate the association between BV and the history of spontaneous abortion and recurrent pregnancy losses. We also examined periods of gestation, including the first and second trimester miscarriages. Materials and Methods: The study population consisted of 200 fertile women. Sixty one (30.5% of 200 women had the history of a spontaneous abortion in the last six months (N = 30 and at least three recurrent pregnancy losses (N = 31. BV was diagnosed either by using Papanicolaou staining, Gram staining, or by culturing with BV-associated bacteria, Gardnerella vaginalis. Results: The presence of BV was statistically associated with the history of a spontaneous abortion in the last 6 months (P 0.05. These women were also evaluated in view of periods of gestation. Forty-seven (77% of 61 women had first trimester miscarriage (≤12 weeks and 14 (23% of 61 women had second trimester miscarriage (>12 weeks. There was a statistically significant relationship between BV and second trimester miscarriage (P 0.05. Conclusion: BV may contribute to spontaneous abortion and second trimester miscarriage.

Case report: an electrocardiogram of spontaneous pneumothorax mimicking arm lead reversal.

Science.gov (United States)

Wieters, J Scott; Carlin, Joseph P; Morris, Andrew

2014-05-01

There are several previously documented findings for electrocardiograms (ECGs) of spontaneous pneumothorax. These findings include axis deviation, T-wave inversion, and right bundle branch block. When an ECG has the arm leads incorrectly placed, the ECG will display right axis deviation and inversion of the P waves in lead I. There have been no previously published ECGs of spontaneous pneumothorax that have shown the same findings as reversal of the limb leads of an ECG. A possible finding of spontaneous pneumothorax is an identical finding to that of an ECG that has been flagged for limb lead reversal. A patient presented in the emergency setting with acute chest pain and shortness of breath caused by a tension pneumothorax. An ECG was administered; findings indicated reversal of the arm leads (right axis deviation and inverted P waves in lead I), but there was no actual limb lead reversal present. ECG findings resolved upon resolution of the pneumothorax. If a patient presents with chest pain and shortness of breath, and the patient's ECG is flagged for limb lead reversal despite being set up correctly, the physician should raise clinical suspicion for a possible spontaneous pneumothorax. Copyright © 2014 Elsevier Inc. All rights reserved.

Ongoing spontaneous activity controls access to consciousness: a neuronal model for inattentional blindness.

Directory of Open Access Journals (Sweden)

Stanislas Dehaene

2005-05-01

Full Text Available Even in the absence of sensory inputs, cortical and thalamic neurons can show structured patterns of ongoing spontaneous activity, whose origins and functional significance are not well understood. We use computer simulations to explore the conditions under which spontaneous activity emerges from a simplified model of multiple interconnected thalamocortical columns linked by long-range, top-down excitatory axons, and to examine its interactions with stimulus-induced activation. Simulations help characterize two main states of activity. First, spontaneous gamma-band oscillations emerge at a precise threshold controlled by ascending neuromodulator systems. Second, within a spontaneously active network, we observe the sudden "ignition" of one out of many possible coherent states of high-level activity amidst cortical neurons with long-distance projections. During such an ignited state, spontaneous activity can block external sensory processing. We relate those properties to experimental observations on the neural bases of endogenous states of consciousness, and particularly the blocking of access to consciousness that occurs in the psychophysical phenomenon of "inattentional blindness," in which normal subjects intensely engaged in mental activity fail to notice salient but irrelevant sensory stimuli. Although highly simplified, the generic properties of a minimal network may help clarify some of the basic cerebral phenomena underlying the autonomy of consciousness.

Ongoing spontaneous activity controls access to consciousness: a neuronal model for inattentional blindness.

Science.gov (United States)

Dehaene, Stanislas; Changeux, Jean-Pierre

2005-05-01

Even in the absence of sensory inputs, cortical and thalamic neurons can show structured patterns of ongoing spontaneous activity, whose origins and functional significance are not well understood. We use computer simulations to explore the conditions under which spontaneous activity emerges from a simplified model of multiple interconnected thalamocortical columns linked by long-range, top-down excitatory axons, and to examine its interactions with stimulus-induced activation. Simulations help characterize two main states of activity. First, spontaneous gamma-band oscillations emerge at a precise threshold controlled by ascending neuromodulator systems. Second, within a spontaneously active network, we observe the sudden "ignition" of one out of many possible coherent states of high-level activity amidst cortical neurons with long-distance projections. During such an ignited state, spontaneous activity can block external sensory processing. We relate those properties to experimental observations on the neural bases of endogenous states of consciousness, and particularly the blocking of access to consciousness that occurs in the psychophysical phenomenon of "inattentional blindness," in which normal subjects intensely engaged in mental activity fail to notice salient but irrelevant sensory stimuli. Although highly simplified, the generic properties of a minimal network may help clarify some of the basic cerebral phenomena underlying the autonomy of consciousness.

Multifractal fluctuations in joint angles during infant spontaneous kicking reveal multiplicativity-driven coordination

International Nuclear Information System (INIS)

Stephen, Damian G.; Hsu, Wen-Hao; Young, Diana; Saltzman, Elliot L.; Holt, Kenneth G.; Newman, Dava J.; Weinberg, Marc; Wood, Robert J.; Nagpal, Radhika; Goldfield, Eugene C.

2012-01-01

Previous research has considered infant spontaneous kicking as a form of exploration. According to this view, spontaneous kicking provides information about motor degrees of freedom and may shape multijoint coordinations for more complex movement patterns such as gait. Recent work has demonstrated that multifractal, multiplicative fluctuations in exploratory movements index energy flows underlying perceptual-motor information. If infant spontaneous kicking is exploratory and occasions an upstream flow of information from the motor periphery, we expected not only that multiplicativity of fluctuations at the hip should promote multiplicativity of fluctuations at more distal joints (i.e., reflecting downstream effects of neural control) but also that multiplicativity at more distal joints should promote multiplicativity at the hip. Multifractal analysis demonstrated that infant spontaneous kicking in four typically developing infants for evidence of multiplicative fluctuations in multiple joint angles along the leg (i.e., hip, knee, and ankle) exhibited multiplicativity. Vector autoregressive modeling demonstrated that only one leg exhibited downstream effects but that both legs exhibited upstream effects. These results confirm the exploratory aspect of infant spontaneous kicking and suggest chaotic dynamics in motor coordination. They also resonate with existing models of chaos-controlled robotics and noise-based interventions for rehabilitating motor coordination in atypically developing patients.

Spontaneous transformation of adult mesenchymal stem cells from cynomolgus macaques in vitro

International Nuclear Information System (INIS)

Ren, Zhenhua; Wang, Jiayin; Zhu, Wanwan; Guan, Yunqian; Zou, Chunlin; Chen, Zhiguo; Zhang, Y. Alex

2011-01-01

Mesenchymal stem cells (MSCs) have shown potential clinical utility in cell therapy and tissue engineering, due to their ability to proliferate as well as to differentiate into multiple lineages, including osteogenic, adipogenic, and chondrogenic specifications. Therefore, it is crucial to assess the safety of MSCs while extensive expansion ex vivo is a prerequisite to obtain the cell numbers for cell transplantation. Here we show that MSCs derived from adult cynomolgus monkey can undergo spontaneous transformation following in vitro culture. In comparison with MSCs, the spontaneously transformed mesenchymal cells (TMCs) display significantly different growth pattern and morphology, reminiscent of the characteristics of tumor cells. Importantly, TMCs are highly tumorigenic, causing subcutaneous tumors when injected into NOD/SCID mice. Moreover, no multiple differentiation potential of TMCs is observed in vitro or in vivo, suggesting that spontaneously transformed adult stem cells may not necessarily turn into cancer stem cells. These data indicate a direct transformation of cynomolgus monkey MSCs into tumor cells following long-term expansion in vitro. The spontaneous transformation of the cultured cynomolgus monkey MSCs may have important implications for ongoing clinical trials and for models of oncogenesis, thus warranting a more strict assessment of MSCs prior to cell therapy. -- Highlights: ► Spontaneous transformation of cynomolgus monkey MSCs in vitro. ► Transformed mesenchymal cells lack multipotency. ► Transformed mesenchymal cells are highly tumorigenic. ► Transformed mesenchymal cells do not have the characteristics of cancer stem cells.

Spontaneous emission in Cherenkov FEL devices

International Nuclear Information System (INIS)

Ciocci, F.; Dattoli, G.; Doria, A.; Schettini, G.; Torre, A.; Walsh, J.E.

1987-01-01

The main features of the spectral characteristics of the spontaneously emitted Cherenkov light in circular and rectangular wave-guides filled with dielectric are discussed. The characteristics of the radiation emitted by an electron beam moving near and parallel to the surface of a dielectric slab are also analysed. Finally, the relevance of these results to a possible FEL-Cherenkov operation is briefly discussed

A Spontaneous Joint Infection with Corynebacterium striatum▿

OpenAIRE

Scholle, David

2006-01-01

Corynebacterium striatum is a ubiquitous saprophyte with the potential to cause bacteremia in immunocompromised patients. Until now, spontaneous infection of a natural joint has not been reported. When phenotyping failed, gene sequencing was used to identify the species. The isolate demonstrated high-level resistance to most antibiotics.

Spontaneous Emission Enhancement at Finite-length Metal

DEFF Research Database (Denmark)

Filonenko, K.; Willatzen, Morten; Bordo, V.

2013-01-01

We study spontaneous emission enhancement of a two-level atomic emitter placed in a dielectric medium near a finite-length cylindrical metal nanowire. We calculate the dependence of the Purcell factor and the normalized decay rate to a continuous spectrum on the nanowire radius for several emitter...

Spontaneous abortion and physical strain around implantation

DEFF Research Database (Denmark)

Hjollund, N H; Jensen, Tina Kold; Bonde, Jens Peter

2000-01-01

pregnancy the women recorded physical strain prospectively in a structured diary. Physical strain around the time of implantation was associated with later spontaneous abortion. The adjusted risk ratio for women who reported physical strain higher than average at day 6 to 9 after the estimated date...

Ultrafast table-top dynamic radiography of spontaneous or stimulated events

Science.gov (United States)

Smilowitz, Laura; Henson, Bryan

2018-01-16

Disclosed herein are representative embodiments of methods, apparatus, and systems for performing radiography. For example, certain embodiments concern X-ray radiography of spontaneous events. Particular embodiments of the disclosed technology provide continuous high-speed x-ray imaging of spontaneous dynamic events, such as explosions, reaction-front propagation, and even material failure. Further, in certain embodiments, x-ray activation and data collection activation are triggered by the object itself that is under observation (e.g., triggered by a change of state detected by one or more sensors monitoring the object itself).

Spontaneous theory of mind and its absence in autism spectrum disorders

OpenAIRE

Senju, Atsushi

2011-01-01

Theory of mind, the cognitive capacity to infer others' mental states, is crucial for the development of social communication. The impairment of theory of mind may relate to autism spectrum disorder (ASD), which is characterized by profound difficulties in social interaction and communication. In the current article, I summarize recent updates in theory of mind research utilizing the spontaneous false belief test, which assesses participants' spontaneous tendency to attribute belief status to...

Burns resulting from spontaneous combustion of electronic cigarettes: a case series

OpenAIRE

Sheckter, Clifford; Chattopadhyay, Arhana; Paro, John; Karanas, Yvonne

2016-01-01

Background Electronic cigarette (e-cigarette) sales have grown rapidly in recent years, coinciding with a public perception that they are a safer alternative to traditional cigarettes. However, there have been numerous media reports of fires associated with e-cigarette spontaneous combustion. Case Presentation Three severe burns caused by spontaneous combustion of e-cigarettes within a 6-month period were treated at the Santa Clara Valley Medical Center Burn Unit. Patients sustained partial a...

Spontaneous ad hoc mobile cloud computing network.

Science.gov (United States)

Lacuesta, Raquel; Lloret, Jaime; Sendra, Sandra; Peñalver, Lourdes

2014-01-01

Cloud computing helps users and companies to share computing resources instead of having local servers or personal devices to handle the applications. Smart devices are becoming one of the main information processing devices. Their computing features are reaching levels that let them create a mobile cloud computing network. But sometimes they are not able to create it and collaborate actively in the cloud because it is difficult for them to build easily a spontaneous network and configure its parameters. For this reason, in this paper, we are going to present the design and deployment of a spontaneous ad hoc mobile cloud computing network. In order to perform it, we have developed a trusted algorithm that is able to manage the activity of the nodes when they join and leave the network. The paper shows the network procedures and classes that have been designed. Our simulation results using Castalia show that our proposal presents a good efficiency and network performance even by using high number of nodes.

Episodic spontaneous hypothermia: a periodic childhood syndrome.

Science.gov (United States)

Ruiz, Cynthia; Gener, Blanca; Garaizar, Carmen; Prats, José M

2003-04-01

Episodic spontaneous hypothermia is an infrequent disorder, with unknown pathogenic mechanisms. A systemic cause or underlying brain lesion has not been found for the disease. We report four new patients, 3-9 years old, with episodic hypothermia lower than 35 degrees C, marked facial pallor, and absent shivering. The episodes could last a few hours or four days, and recurred once a week or every 2-3 months. Two patients also demonstrated bradycardia, mild hypertension, and somnolence during the events; in one of them, profuse sweating was also a feature, and all four presented with either headache, a periodic childhood syndrome, or both (recurrent abdominal pain, cyclic vomiting, or vertigo). Three patients reported a family history of migraine. Neurologic examination, endocrine function, and imaging studies were normal. Migraine prophylactic therapy was of moderate efficacy. Spontaneous resolution was observed in one patient. The clinical characteristics of the syndrome allow for its inclusion as a childhood periodic syndrome related to migraine.

Thermal influences on spontaneous rock dome exfoliation

Science.gov (United States)

Collins, Brian D.; Stock, Greg M.; Eppes, Martha C.; Lewis, Scott W.; Corbett, Skye C.; Smith, Joel B.

2018-01-01

Rock domes, with their onion-skin layers of exfoliation sheets, are among the most captivating landforms on Earth. Long recognized as integral in shaping domes, the exact mechanism(s) by which exfoliation occurs remains enigmatic, mainly due to the lack of direct observations of natural events. In August 2014, during the hottest days of summer, a granitic dome in California, USA, spontaneously exfoliated; witnesses observed extensive cracking, including a ~8000 kg sheet popping into the air. Subsequent exfoliation episodes during the following two summers were recorded by instrumentation that captured—for the first time—exfoliation deformation and stress conditions. Here we show that thermal cycling and cumulative dome surface heating can induce subcritical cracking that culminates in seemingly spontaneous exfoliation. Our results indicate that thermal stresses—largely discounted in dome formation literature—can play a key role in triggering exfoliation and therefore may be an important control for shaping domes worldwide.

Duality transformation of a spontaneously broken gauge theory

International Nuclear Information System (INIS)

Mizrachi, L.

1981-04-01

Duality transformation for a spontaneously broken gauge theory is constructed in the CDS gauge (xsub(μ)Asub(μ)sup(a)=0). The dual theory is expressed in terms of dual potentials which satisfy the same gauge condition, but with g→ 1 /g. Generally the theory is not self dual but in the weak coupling region (small g), self duality is found for the subgroup which is not spontaneously broken or in regions where monopoles and vortices are concentrated (in agreement with t'Hooft's ideas that monopoles and vortices in the Georgi-Glashow model make it self dual). In the strong coupling regime a systematic strong coupling expansion can be written. For this region the dual theory is generally not local gauge invariant, but it is invariant under global gauge transformations. (author)

Spontaneous Unruptured Bilateral Tubal Pregnancy: A Case Report

Directory of Open Access Journals (Sweden)

Nayereh Ghomian

2015-11-01

Full Text Available Bilateral spontaneous tubal ectopic pregnancy is the rarest form of extra uterine pregnancy. The diagnosis is usually made intraoperatively and levels of serum BHCG and ultrasound has not been useful in the diagnosis of bilateral tubal ectopic pregnancy. A 33-year-old woman with 8 weeks amenorrhea and sever lower abdominal pain was admitted. A transvaginal pelvic ultrasound revealed left adnexal mass and massive fluid collection in the pelvis and abdomen. The serum BHCG was 5,700 mIU/ml and in laparotomy bilateral unruptured tubal pregnancy was noted. Left salpingectomy and right salpingostomy were performed. The diagnosis of bilateral spontaneous tubal ectopic pregnancy is usually made intraoperatively. Both tubes at the time of surgery should be closely examined in order to prevent maternal morbidity and mortality.

Electrically induced spontaneous emission in open electronic system

Science.gov (United States)

Wang, Rulin; Zhang, Yu; Yam, Chiyung; Computation Algorithms Division (CSRC) Team; Theoretical; Computational Chemistry (HKU) Collaboration

A quantum mechanical approach is formulated for simulation of electroluminescence process in open electronic system. Based on nonequilibrium Green's function quantum transport equations and combining with photon-electron interaction, this method is used to describe electrically induced spontaneous emission caused by electron-hole recombination. The accuracy and reliability of simulation depends critically on correct description of the electronic band structure and the electron occupancy in the system. In this work, instead of considering electron-hole recombination in discrete states in the previous work, we take continuous states into account to simulate the spontaneous emission in open electronic system, and discover that the polarization of emitted photon is closely related to its propagation direction. Numerical studies have been performed to silicon nanowire-based P-N junction with different bias voltage.

Attempt to enrich of a new spontaneous fissioning nuclide by evaporation of natural brine

International Nuclear Information System (INIS)

Adamek, A.; Zhuravleva, E.L.; Constantinescu, M.; Constantinescu, o.; Chuburkov, Yu.T.

1983-01-01

The enrichment of the new spontaneous fissioning nuclide discovered in the Cheleken brine, was made by evaporation. The purpose of this work was the comparison of behaviour of the new spontaneous fissioning nuclide with that of the known elements in the formation processes of the high concentration brines. Spontaneous fission of the nuclide was measured by means of the counters for multiple emission of neutrons. It is shown that the new spontaneous fissioning nuclide was enriched as well as other trace elements (Hg, Tl, Bi and Pb) in a solution remained after the evaporation of the initial solution. The conclusion is drawn that from the sea water brines could be obtained by evaporation which are enriched in trace elements with an enrichment degree higher than the natural brines

Recurrence of primary spontaneous pneumothorax in young adults and children.

Science.gov (United States)

Noh, Dongsub; Lee, Sungsoo; Haam, Seok Jin; Paik, Hyo Chae; Lee, Doo Yun

2015-08-01

Although better nutritional support has improved the growth rates in children, the occurrence of primary spontaneous pneumothorax has also been increasing in children. The current study attempts to investigate the occurrence and recurrence of primary spontaneous pneumothorax and the efficacy of surgery for primary spontaneous pneumothorax in young adults and children. A total of 840 patients were treated for pneumothorax at our hospital from January 2006 to December 2010. Exclusion criteria for this study were age >25 or secondary, traumatic or iatrogenic pneumothorax, and a total of 517 patients were included. Patients were classified into three groups according to age at the first episode of primary spontaneous pneumothorax: Group A: ≤16 years; Group B: 17-18 years and Group C: ≥19 years. The study group was composed of 470 male and 47 female patients. There were 234 right-sided, 279 left-sided and 4 bilateral primary spontaneous pneumothoraces. Wedge resection by video-assisted thoracic surgery was performed in 285 patients, while 232 were managed by observation or closed thoracostomy. In the wedge resection group, 51 patients experienced recurrence. The recurrence rates after wedge resection were 27.9% in Group A, 16.5% in Group B and 13.2% in Group C (P = 0.038). The recurrence rates after observation or closed thoracostomy were 45.7% in Group A, 51.9% in Group B and 47.7% in Group C (P = 0.764). In the present study, postoperative recurrence rates were higher than those in the literature. Intense and long-term follow-up was probably one reason for the relatively high recurrence rate. The recurrence rate after wedge resection in patients aged ≤16 years was higher than that in older patients. There was no difference between the recurrence rates after observation or closed thoracostomy, regardless of age. These results suggest that wedge resection might be delayed in children. © The Author 2015. Published by Oxford University Press on behalf of the

Spontaneous regression of cerebral arteriovenous malformations: clinical and angiographic analysis with review of the literature

International Nuclear Information System (INIS)

Lee, S.K.; Vilela, P.; Willinsky, R.; TerBrugge, K.G.

2002-01-01

Spontaneous regression of cerebral arteriovenous malformation (AVM) is rare and poorly understood. We reviewed the clinical and angiographic findings in patients who had spontaneous regression of cerebral AVMs to determine whether common features were present. The clinical and angiographic findings of four cases from our series and 29 cases from the literature were retrospectively reviewed. The clinical and angiographic features analyzed were: age at diagnosis, initial presentation, venous drainage pattern, number of draining veins, location of the AVM, number of arterial feeders, clinical events during the interval period to thrombosis, and interval period to spontaneous thrombosis. Common clinical and angiographic features of spontaneous regression of cerebral AVMs are: intracranial hemorrhage as an initial presentation, small AVMs, and a single draining vein. Spontaneous regression of cerebral AVMs can not be predicted by clinical or angiographic features, therefore it should not be considered as an option in cerebral AVM management, despite its proven occurrence. (orig.)

Analysis of SOS-Induced Spontaneous Prophage Induction in Corynebacterium glutamicum at the Single-Cell Level

Science.gov (United States)

Nanda, Arun M.; Heyer, Antonia; Krämer, Christina; Grünberger, Alexander; Kohlheyer, Dietrich

2014-01-01

The genome of the Gram-positive soil bacterium Corynebacterium glutamicum ATCC 13032 contains three integrated prophage elements (CGP1 to -3). Recently, it was shown that the large lysogenic prophage CGP3 (∼187 kbp) is excised spontaneously in a small number of cells. In this study, we provide evidence that a spontaneously induced SOS response is partly responsible for the observed spontaneous CGP3 induction. Whereas previous studies focused mainly on the induction of prophages at the population level, we analyzed the spontaneous CGP3 induction at the single-cell level using promoters of phage genes (Pint2 and Plysin) fused to reporter genes encoding fluorescent proteins. Flow-cytometric analysis revealed a spontaneous CGP3 activity in about 0.01 to 0.08% of the cells grown in standard minimal medium, which displayed a significantly reduced viability. A PrecA-eyfp promoter fusion revealed that a small fraction of C. glutamicum cells (∼0.2%) exhibited a spontaneous induction of the SOS response. Correlation of PrecA to the activity of downstream SOS genes (PdivS and PrecN) confirmed a bona fide induction of this stress response rather than stochastic gene expression. Interestingly, the reporter output of PrecA and CGP3 promoter fusions displayed a positive correlation at the single-cell level (ρ = 0.44 to 0.77). Furthermore, analysis of the PrecA-eyfp/Pint2-e2-crimson strain during growth revealed the highest percentage of spontaneous PrecA and Pint2 activity in the early exponential phase, when fast replication occurs. Based on these studies, we postulate that spontaneously occurring DNA damage induces the SOS response, which in turn triggers the induction of lysogenic prophages. PMID:24163339

Rapid Spontaneously Resolving Acute Subdural Hematoma

Science.gov (United States)

Gan, Qi; Zhao, Hexiang; Zhang, Hanmei; You, Chao

2017-01-01

Introduction: This study reports a rare patient of a rapid spontaneously resolving acute subdural hematoma. In addition, an analysis of potential clues for the phenomenon is presented with a review of the literature. Patient Presentation: A 1-year-and-2-month-old boy fell from a height of approximately 2 m. The patient was in a superficial coma with a Glasgow Coma Scale of 8 when he was transferred to the authors’ hospital. Computed tomography revealed the presence of an acute subdural hematoma with a midline shift beyond 1 cm. His guardians refused invasive interventions and chose conservative treatment. Repeat imaging after 15 hours showed the evident resolution of the hematoma and midline reversion. Progressive magnetic resonance imaging demonstrated the complete resolution of the hematoma, without redistribution to a remote site. Conclusions: Even though this phenomenon has a low incidence, the probability of a rapid spontaneously resolving acute subdural hematoma should be considered when patients present with the following characteristics: children or elderly individuals suffering from mild to moderate head trauma; stable or rapidly recovered consciousness; and simple acute subdural hematoma with a moderate thickness and a particularly low-density band in computed tomography scans. PMID:28468224

Ovarian hyperstimulation syndrome in a spontaneous pregnancy ...

African Journals Online (AJOL)

It is known that most cases of Ovarian Hyperstimulation Syndrome (OHSS) are associated with the therapies for ovulation induction. However, OHSS may rarely be associated with a spontaneous ovulatory cycle, usually in the case of multiple gestations, hypothyroidism or polycystic ovary syndrome. We report a case of ...

Spontaneous hedonic reactions to social media cues

NARCIS (Netherlands)

Koningsbruggen, G.M. van; Hartmann, T.; Eden, A.; Veling, H.P.

2017-01-01

Why is it so difficult to resist the desire to use social media? One possibility is that frequent social media users possess strong and spontaneous hedonic reactions to social media cues, which, in turn, makes it difficult to resist social media temptations. In two studies (total N = 200), we

Prevention of spontaneous combustion in coal stockpiles : Experimental results in coal storage yard

NARCIS (Netherlands)

Fierro, V.; Miranda, J.L.; Romero, C.; Andrés, J.M.; Arriaga, A.; Schmal, D.; Visser, G.H.

1999-01-01

The spontaneous ignition of coal stockpiles is a serious economic and safety problem. This paper deals with oxidation and spontaneous combustion of coal piles laid in coal storage yard and the measures to avoid the heat losses produced. Investigations on self heating were carried out with five test

Spontaneous forniceal rupture: Can it be treated conservatively?

Directory of Open Access Journals (Sweden)

Ahmed Gaber Al-mujalhem

2017-01-01

Conclusion: Spontaneous forniceal rupture is more likely to occur with smaller distal ureteric stones. Conservative management is a valid option in non-complicated cases. Intervention should be reserved to complicated cases or cases with sizable urinoma.