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1.
Nervenarzt ; 93(1): 93-101, 2022 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-34978577

RESUMEN

Stopping antidepressants can cause withdrawal (discontinuation) symptoms, the return of the original illness, and rebound. The latter means that the disease will return stronger, faster, or with greater likelihood than if it had not been treated with medication. The Psychiatry Working Group of the Drug Commission of the German Medical Association (AkdÄ) presents the scientific findings and provides practical recommendations for action. Withdrawal symptoms are multiform; unspecific physical symptoms are predominant. Distinguishing them from the recurrence of depressive symptoms can be difficult. Most of them are mild and self-limiting. There is insufficient evidence on the extent and frequency of rebound depression. The rebound risk implies that when establishing the medication, the short-term benefit must be weighed against the possible long-term risk of chronic depression or the possible need for long-term medication. Patients should be informed about the risk of withdrawal both as early as the joint decision-making process about treatment initiation and regularly during the course of treatment. Withdrawal should take place gradually, except in emergency situations, whereby small steps should be taken, especially in the low-dose range.


Asunto(s)
Antidepresivos , Síndrome de Abstinencia a Sustancias , Antidepresivos/efectos adversos , Depresión , Humanos , Síndrome de Abstinencia a Sustancias/diagnóstico
2.
Phys Rev Lett ; 127(10): 103201, 2021 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-34533326

RESUMEN

We report on a joint experimental and theoretical study of photoelectron circular dichroism (PECD) in methyloxirane. By detecting O 1s photoelectrons in coincidence with fragment ions, we deduce the molecule's orientation and photoelectron emission direction in the laboratory frame. Thereby, we retrieve a fourfold differential PECD clearly beyond 50%. This strong chiral asymmetry is reproduced by ab initio electronic structure calculations. Providing such a pronounced contrast makes PECD of fixed-in-space chiral molecules an even more sensitive tool for chiral recognition in the gas phase.

3.
Phys Rev Lett ; 117(8): 083002, 2016 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-27588854

RESUMEN

We investigate the photodouble ionization of H_{2} molecules with 400 eV photons. We find that the emitted electrons do not show any sign of two-center interference fringes in their angular emission distributions if considered separately. In contrast, the quasiparticle consisting of both electrons (i.e., the "dielectron") does. The work highlights the fact that nonlocal effects are embedded everywhere in nature where many-particle processes are involved.

4.
Phys Rev Lett ; 116(7): 073201, 2016 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-26943532

RESUMEN

Even though the study of ion-atom collisions is a mature field of atomic physics, large discrepancies between experiment and theoretical calculations are still common. Here we present experimental results with high momentum resolution on the single ionization of helium induced by 1-MeV protons, and we compare these to theoretical calculations. The overall agreement is strikingly good, and even the first Born approximation yields good agreement between theory and experiment. This has been expected for several decades, but so far has not been accomplished. The influence of projectile coherence effects on the measured data is briefly discussed in terms of an ongoing dispute on the existence of nodal structures in the electron angular emission distributions.

5.
Phys Rev Lett ; 111(11): 113003, 2013 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-24074083

RESUMEN

We report on the observation of discrete structures in the electron energy distribution for strong field double ionization of argon at 394 nm. The experimental conditions were chosen in order to ensure a nonsequential ejection of both electrons with an intermediate rescattering step. We have found discrete above-threshold ionization like peaks in the sum energy of both electrons, as predicted by all quantum mechanical calculations. More surprisingly, however, is the observation of two above-threshold ionization combs in the energy distribution of the individual electrons.

6.
Phys Rev Lett ; 111(2): 023002, 2013 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-23889391

RESUMEN

We report experimental observation of the energy sharing between electron and nuclei in above-threshold multiphoton dissociative ionization of H2 by strong laser fields. The absorbed photon energy is shared between the ejected electron and nuclei in a correlated fashion, resulting in multiple diagonal lines in their joint energy spectrum governed by the energy conservation of all fragment particles.

7.
Phys Rev Lett ; 111(23): 233004, 2013 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-24476268

RESUMEN

We investigate the ionization of HeNe from below the He 1s3p excitation to the He ionization threshold. We observe HeNe+ ions with an enhancement by more than a factor of 60 when the He side couples resonantly to the radiation field. These ions are an experimental proof of a two-center resonant photoionization mechanism predicted by Najjari et al. [Phys. Rev. Lett. 105, 153002 (2010)]. Furthermore, our data provide electronic and vibrational state resolved decay widths of interatomic Coulombic decay in HeNe dimers. We find that the interatomic Coulombic decay lifetime strongly increases with increasing vibrational state.

8.
Phys Rev Lett ; 111(9): 093401, 2013 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-24033031

RESUMEN

During the past 15 years a novel decay mechanism of excited atoms has been discovered and investigated. This so-called interatomic Coulombic decay (ICD) involves the chemical environment of the electronically excited atom: the excitation energy is transferred (in many cases over long distances) to a neighbor of the initially excited particle usually ionizing that neighbor. It turned out that ICD is a very common decay route in nature as it occurs across van der Waals and hydrogen bonds. The time evolution of ICD is predicted to be highly complex, as its efficiency strongly depends on the distance of the atoms involved and this distance typically changes during the decay. Here we present the first direct measurement of the temporal evolution of ICD using a novel experimental approach.

9.
Rev Sci Instrum ; 92(2): 023205, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33648096

RESUMEN

Many samples of current interest in molecular physics and physical chemistry exist in the liquid phase and are vaporized for use in gas cells, diffuse gas targets, or molecular gas jets. For some of these techniques, the large sample consumption is a limiting factor. When rare, expensive molecules such as custom-made chiral molecules or species with isotopic labels are used, wasting them in the exhaust line of the pumps is quite an expensive and inefficient approach. Therefore, we developed a closed-loop recycling system for molecules with vapor pressures below atmospheric pressure. Once filled, only a few valves have to be adjusted, and a cold trap must be moved after each phase of recycling. The recycling efficiency per turn exceeds 95%.

10.
Acta Psychiatr Scand ; 121(1): 52-64, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19489749

RESUMEN

OBJECTIVE: We investigated in a high-risk sample the differential impact of biological and psychosocial risk factors on antisocial behaviour pathways. METHOD: One hundred and thirty-eight boys and 155 girls born at differing degrees of obstetric and psychosocial risk were examined from birth until adolescence. Childhood temperament was assessed by a highly-structured parent-interview and standardized behavioural observations, adolescent temperament was measured by self-report. Neurodevelopmental variables were assessed by age-specific developmental tests. Emotional and behaviour problems were measured at the ages of 8 and 15 by the Achenbach scales. RESULTS: In both genders, psychosocial adversity and early self-control temperament were strongly associated with early-onset persistent (EOP) antisocial behaviour. Psychosocial adversity and more severe externalizing problems differentiated the EOP from childhood-limited (CL) pathway. In girls, adolescent-onset (AO) antisocial behaviour was strongly associated with novelty seeking at 15 years. CONCLUSION: Our findings emphasize the need for early support and intervention in psychosocially disadvantaged families.


Asunto(s)
Síntomas Afectivos/diagnóstico , Trastorno de Personalidad Antisocial/diagnóstico , Temperamento , Adolescente , Síntomas Afectivos/psicología , Edad de Inicio , Trastorno de Personalidad Antisocial/psicología , Niño , Trastornos de la Conducta Infantil/diagnóstico , Trastornos de la Conducta Infantil/psicología , Preescolar , Discapacidades del Desarrollo/diagnóstico , Discapacidades del Desarrollo/psicología , Diagnóstico Precoz , Femenino , Humanos , Lactante , Recién Nacido , Estudios Longitudinales , Masculino , Determinación de la Personalidad , Pronóstico , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores Sexuales , Encuestas y Cuestionarios , Poblaciones Vulnerables/psicología , Poblaciones Vulnerables/estadística & datos numéricos
11.
Sci Adv ; 5(3): eaau7923, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30873429

RESUMEN

Chirality is omnipresent in living nature. On the single molecule level, the response of a chiral species to a chiral probe depends on their respective handedness. A prominent example is the difference in the interaction of a chiral molecule with left or right circularly polarized light. In the present study, we show by Coulomb explosion imaging that circularly polarized light can also induce a chiral fragmentation of a planar and thus achiral molecule. The observed enantiomer strongly depends on the orientation of the molecule with respect to the light propagation direction and the helicity of the ionizing light. This finding might trigger new approaches to improve laser-driven enantioselective chemical synthesis.

12.
Nat Commun ; 9(1): 2259, 2018 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-29872047

RESUMEN

The original version of this Article contained an error in the fifth sentence of the first paragraph of the 'Application on H2' section of the Results, which incorrectly read 'The role of electron correlation is quite apparent in this presentation: Fig. 1a is empty for the uncorrelated Hartree-Fock wave function, since projection of the latter wave function onto the 2pσu orbital is exactly zero, while this is not the case for the fully correlated wave function (Fig. 1d); also, Fig. 1b, c for the uncorrelated description are identical, while Fig. 1e, f for the correlated case are significantly different.' The correct version replaces 'Fig. 1e, f' with 'Fig. 2e and f'.

13.
Nat Commun ; 8(1): 2266, 2017 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-29273745

RESUMEN

The toolbox for imaging molecules is well-equipped today. Some techniques visualize the geometrical structure, others the electron density or electron orbitals. Molecules are many-body systems for which the correlation between the constituents is decisive and the spatial and the momentum distribution of one electron depends on those of the other electrons and the nuclei. Such correlations have escaped direct observation by imaging techniques so far. Here, we implement an imaging scheme which visualizes correlations between electrons by coincident detection of the reaction fragments after high energy photofragmentation. With this technique, we examine the H2 two-electron wave function in which electron-electron correlation beyond the mean-field level is prominent. We visualize the dependence of the wave function on the internuclear distance. High energy photoelectrons are shown to be a powerful tool for molecular imaging. Our study paves the way for future time resolved correlation imaging at FELs and laser based X-ray sources.

14.
J Comp Neurol ; 426(1): 143-53, 2000 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-10980489

RESUMEN

Survival of embryonic dopamine (DA) neurons is extremely low (5-20%) following transplantation. Strategies to increase this survival are critical to the future of transplantation for Parkinson's disease. We demonstrate here that a factor(s) released from striatal oligodendrocyte-type 2 astrocytes (SO2A) greatly improves the survival and phenotype expression of mesencephalic DA neurons in culture while simultaneously decreasing the presence of apoptotic nuclear profiles, as detected by the TUNEL method and bisbenzamide/tyrosine hydroxylase double labeling. This SO2A-derived trophic factor(s) has minimal effects on glia and no effect on nondopaminergic mesencephalic neurons. The developmental period during which this SO2A trophic effect occurs (E14-18) coincides with the period when mesencephalic grafts are undergoing the highest rates of apoptosis, i.e., immediately following implantation. Therefore, SO2A-derived trophic factor(s) offers great potential for the augmentation of grafted DA neuron survival.


Asunto(s)
Apoptosis/efectos de los fármacos , Astrocitos/metabolismo , Supervivencia Celular/efectos de los fármacos , Dopamina/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Neuronas/efectos de los fármacos , Oligodendroglía/metabolismo , Animales , Apoptosis/fisiología , Astrocitos/citología , Trasplante de Tejido Encefálico/métodos , Supervivencia Celular/fisiología , Células Cultivadas , Medios de Cultivo Condicionados/farmacología , Relación Dosis-Respuesta a Droga , Femenino , Feto , Factor 2 de Crecimiento de Fibroblastos/farmacología , Necrosis , Neuronas/metabolismo , Neuronas/trasplante , Oligodendroglía/citología , Enfermedad de Parkinson/terapia , Fenotipo , Factor de Crecimiento Derivado de Plaquetas/farmacología , Embarazo , Ratas , Ratas Endogámicas F344 , Células Madre/citología , Células Madre/efectos de los fármacos , Células Madre/metabolismo , Tirosina 3-Monooxigenasa/efectos de los fármacos , Tirosina 3-Monooxigenasa/metabolismo
15.
Behav Brain Res ; 59(1-2): 83-93, 1993 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-8155296

RESUMEN

Injections of the GABAB agonist baclofen into the median raphe nucleus (MR) resulted in marked hyperactivity and in increases in food and water intake by non-deprived animals. The locomotor effects of baclofen were stereospecific and could be antagonized by coinjection of the GABAB antagonist 2-hydroxysaclofen. Hyperactivity was produced by lower doses of baclofen, at shorter latencies, when the drug was injected into the MR than when it applied to the dorsal raphe nucleus (DR) or the ventral tegmental area (VTA). The locomotor response to intra-MR baclofen was unaltered in animals pretreated with the serotonin synthesis inhibitor p-chlorophenylalanine. Finally, intra-MR injections of baclofen produced a large increase in dopamine metabolism in the nucleus accumbens and striatum but failed to alter hippocampal or striatal serotonin metabolism. These findings suggest that baclofen may produce increases in activity and ingestive behavior as a result of an action on non-serotonergic cells in the MR.


Asunto(s)
Conducta Animal/fisiología , Núcleos del Rafe/fisiología , Receptores de GABA-B/fisiología , Animales , Baclofeno/administración & dosificación , Baclofeno/análogos & derivados , Baclofeno/antagonistas & inhibidores , Baclofeno/farmacología , Conducta Animal/efectos de los fármacos , Mapeo Encefálico , Dopamina/metabolismo , Ingestión de Líquidos/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Fenclonina/farmacología , Inyecciones , Masculino , Actividad Motora/efectos de los fármacos , Prosencéfalo/efectos de los fármacos , Prosencéfalo/metabolismo , Núcleos del Rafe/efectos de los fármacos , Núcleos del Rafe/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de GABA-B/efectos de los fármacos , Serotonina/metabolismo , Estereoisomerismo
16.
Brain Res ; 633(1-2): 21-6, 1994 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-8137158

RESUMEN

In rats treated systemically with either amphetamine, amfonelic acid or apomorphine, large numbers of cells displaying Fos-like immunoreactivity (FLI) could be seen in the lateral zone of the lateral habenula. The induction of FLI by amphetamine could be blocked either by pretreatment with haloperidol or by 6-hydroxydopamine lesions of ascending dopamine fibers at the level of the lateral hypothalamus. In contrast, a variety of stressors selectively induced FLI in the most medial portion of the lateral habenula. These findings support the concept of a functional differentiation of the medial and lateral regions of the lateral habenula and provide further evidence for involvement of the habenula in the circuitry of the basal ganglia.


Asunto(s)
Dopamina/fisiología , Proteínas Oncogénicas v-fos/metabolismo , Estrés Psicológico/metabolismo , Tálamo/metabolismo , Animales , Apomorfina/farmacología , Dextroanfetamina/farmacología , Ambiente , Haloperidol/farmacología , Inmunohistoquímica , Cloruro de Litio/farmacología , Masculino , Ácido Nalidíxico/análogos & derivados , Naftiridinas/farmacología , Neostriado/efectos de los fármacos , Neostriado/metabolismo , Proteínas Oncogénicas v-fos/inmunología , Oxidopamina/farmacología , Prosencéfalo/efectos de los fármacos , Prosencéfalo/metabolismo , Ratas , Ratas Sprague-Dawley , Restricción Física , Sustancia Negra/efectos de los fármacos , Sustancia Negra/metabolismo , Tálamo/efectos de los fármacos
17.
AORN J ; 64(3): 376-7, 380-2, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8876919

RESUMEN

Retrohepatic inferior vena caval injuries resulting from blunt or penetrating abdominal trauma are rare but devastating events that remain formidable challenges to even the most experienced Level I trauma center team members. Prepackaged atrial caval shunts have improved emergency medical treatments, and prior planning and coordination by perioperative nurses allow for rapid response by surgical team members. These efforts provide an optimal level of care required to increase patient survival. This article provides a general overview of abdominal trauma and retrohepatic inferior vena caval injuries and a proactive plan to meet the needs of patients with these injuries.


Asunto(s)
Atrios Cardíacos/cirugía , Hígado/lesiones , Enfermería Perioperatoria , Vena Cava Inferior/lesiones , Vena Cava Inferior/cirugía , Traumatismos Abdominales/complicaciones , Traumatismos Abdominales/enfermería , Traumatismos Abdominales/cirugía , Humanos , Equipo Quirúrgico
18.
Z Kinder Jugendpsychiatr Psychother ; 28(2): 119-28, 2000 May.
Artículo en Alemán | MEDLINE | ID: mdl-10863768

RESUMEN

Proceeding from the Clinical Descriptions and Diagnostic Guidelines of the ICD-10, a table of reference to DSM-IV is presented for mental disorders. Emphasis is placed upon childhood and adolescent mental disorder pictures. Allowance is made in the corresponding notes for greater content differences in the operationalization of individual disorder pictures. However, the table can only serve as a pointer to diagnoses in DSM-IV that correspond to those in ICD-10. In the interests of greater diagnostic security, these should be checked in individual cases against the diagnostic criteria. In the forefront certain theoretical considerations with regard to the comparison of the two classification systems are illustrated by means of selected disorder pictures.


Asunto(s)
Grupos Diagnósticos Relacionados/normas , Trastornos Mentales/clasificación , Trastornos Mentales/diagnóstico , Adulto , Niño , Humanos , Estándares de Referencia
19.
Nat Commun ; 4: 2177, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23867800

RESUMEN

Electron motion in chemical bonds occurs on an attosecond timescale. This ultrafast motion can be driven by strong laser fields. Ultrashort asymmetric laser pulses are known to direct electrons to a certain direction. But do symmetric laser pulses destroy symmetry in breaking chemical bonds? Here we answer this question in the affirmative by employing a two-particle coincidence technique to investigate the ionization and fragmentation of H2 by a long circularly polarized multicycle femtosecond laser pulse. Angular streaking and the coincidence detection of electrons and ions are employed to recover the phase of the electric field, at the instant of ionization and in the molecular frame, revealing a phase-dependent anisotropy in the angular distribution of H⁺ fragments. Our results show that electron localization and asymmetrical breaking of molecular bonds are ubiquitous, even in symmetric laser pulses. The technique we describe is robust and provides a powerful tool for ultrafast science.

20.
Brain Behav Evol ; 50(3): 152-66, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9288415

RESUMEN

The distribution of reduced nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-D) was mapped histochemically in the forebrain of Rana pipiens, the leopard frog. Intense staining was observed which was strikingly restricted to certain nuclear groups and fiber tracts. The densest concentrations of NADPH-D stained cell bodies and fibers were observed in the granule layer of the accessory olfactory bulb and in the ventral aspect of the lateral pallium. Intense staining has also been reported in the presumed mammalian homologues of these regions. Less densely packed clusters of intensely stained neurons were found in the striatum, the anterior entopeduncular nucleus, the olfactory tubercle and the pars lateralis of the amygdala, whereas the preoptic region and the medial septum exhibited dense accumulations of lightly stained cells. Several fiber systems or terminal fields could be detected, including a ring of heavy staining which enclosed the striatum and an apparent terminal field in the lateral part of the medial pallium. A prominent compact tract, which may be homologous to a component of the stria terminalis of mammals, could be also followed from the ventral portion of the lateral pallium to the infundibular hypothalamus.


Asunto(s)
NADPH Deshidrogenasa/metabolismo , Vías Nerviosas/anatomía & histología , Telencéfalo/enzimología , Animales , Mapeo Encefálico , Rana pipiens , Telencéfalo/fisiología
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