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1.
J Cardiovasc Dev Dis ; 10(7)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37504546

RESUMO

Fontan patients undergo multiple cardiothoracic surgeries in childhood. Following these procedures, ventricular function is temporarily decreased, and recovers over months. This is presumably related to cardiopulmonary bypass, but this is incompletely understood. Throughout the Fontan palliation, cardiac function is also affected by volume unloading. We aimed to gain insight into the biological processes related to impaired ventricular function and recovery following Fontan palliations using a panel of biomarkers. Furthermore, we described changes in ventricular function across the Fontan palliation due to volume unloading. We performed a prospective multicenter observational study in patients undergoing partial (PCPC) or total cavo-pulmonary connection (TCPC). Patients underwent assessment-including echocardiography and blood sampling-before surgery (T1), at first follow-up (T2), and 1 year after their procedures (T3). Blood samples were analyzed using a biomarker panel (OLINK CVD-III). Ninety-two biomarkers were expressed as principal components (PC) to limit multiple statistical testing. We included 32 PCPC patients aged 7.2 [5.3-10.3] months, and 28 TCPC patients aged 2.7 [2.2-3.8] years. The single ventricular longitudinal strain (SV GLS) temporarily decreased for PCPC patients at T2 (-15.1 ± 5.6 (T1) to -13.5 ± 5.2 (T2) to -17.3 ± 4.5 (T3), p < 0.047 for all differences), but not following TCPC. The serum biomarkers were expressed as 4 PCs. PC1, including biomarkers of cell-cell adhesion, was not related to any patient characteristic. PC2, including biomarkers of superoxide anion regulation, increased at T2. PC3, including biomarkers of cardiovascular development, related to the stage of Fontan palliation. PC4 was of uncertain biological or clinical significance. No PC was found that related to ventricular performance. The SV GLS was temporarily diminished following PCPC, but not following TCPC. Several biomarkers were related to post-operative stress and adaptation to the PCPC or TCPC circulation, but none were related to the outcome.

2.
Br J Cancer ; 128(8): 1503-1513, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36759720

RESUMO

BACKGROUND: This trial investigated the hypothesis that the treatment with trabectedin/PLD (TP) to extend the platinum-free interval (TFIp) can improve overall survival (OS) in patients with recurrent ovarian cancer (OC). METHODS: Patients with OC (up to two previous platinum-based lines), with a TFIp of 6-12 months, were randomised to receive carboplatin/PLD (CP) or TP followed by platinum therapy at relapse. The primary endpoint was OS (HR: 0.75). RESULTS: The study enrolled 617 patients. The median TFIp was 8.3 months and 30.3% of patients had received two previous platinum lines. 74% and 73.9% of patients, respectively, received a subsequent therapy (ST) in the CP and TP arm; in the latter TP arm 87.2% of ST was platinum-based, as per protocol. The median OS was 21.4 for CP and 21.9 months for TP (HR 1.13; 95% CI: 0.94-1.35; p = 0.197). Grade 3-5 adverse reactions occurred in 37.1% of patients in the CP arm and 69.7% of patients in the TP arm, and the most frequent were neutropenia (22.8% CP, 39.5% TP), gastrointestinal (7.1% CP, 17.4% TP), hepatic (0.7% CP, 19.1% TP). CONCLUSIONS: This study did not meet the primary endpoint. CP combination remains the standard for patients with recurrent OC and a 6-12 months TFIp; TP is an effective treatment in patients suffering from persistent platinum toxicities. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, number NCT01379989.


Assuntos
Neoplasias Ovarianas , Humanos , Feminino , Carboplatina , Trabectedina , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/etiologia , Platina/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/etiologia , Carcinoma Epitelial do Ovário/tratamento farmacológico , Doxorrubicina , Polietilenoglicóis , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
3.
Phys Rev E ; 107(1-2): 015202, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36797905

RESUMO

In order to understand how close current layered implosions in indirect-drive inertial confinement fusion are to ignition, it is necessary to measure the level of alpha heating present. To this end, pairs of experiments were performed that consisted of a low-yield tritium-hydrogen-deuterium (THD) layered implosion and a high-yield deuterium-tritium (DT) layered implosion to validate experimentally current simulation-based methods of determining yield amplification. The THD capsules were designed to reduce simultaneously DT neutron yield (alpha heating) and maintain hydrodynamic similarity with the higher yield DT capsules. The ratio of the yields measured in these experiments then allowed the alpha heating level of the DT layered implosions to be determined. The level of alpha heating inferred is consistent with fits to simulations expressed in terms of experimentally measurable quantities and enables us to infer the level of alpha heating in recent high-performing implosions.

4.
Phys Rev Lett ; 127(10): 103201, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34533326

RESUMO

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.

5.
Phys Rev Lett ; 127(3): 033001, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34328758

RESUMO

Isotope shifts of ^{223-226,228}Ra^{19}F were measured for different vibrational levels in the electronic transition A^{2}Π_{1/2}←X^{2}Σ^{+}. The observed isotope shifts demonstrate the particularly high sensitivity of radium monofluoride to nuclear size effects, offering a stringent test of models describing the electronic density within the radium nucleus. Ab initio quantum chemical calculations are in excellent agreement with experimental observations. These results highlight some of the unique opportunities that short-lived molecules could offer in nuclear structure and in fundamental symmetry studies.

6.
Rev Sci Instrum ; 92(2): 023205, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648096

RESUMO

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%.

7.
Phys Rev E ; 102(2-1): 023210, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32942378

RESUMO

This paper presents a study on hotspot parameters in indirect-drive, inertially confined fusion implosions as they proceed through the self-heating regime. The implosions with increasing nuclear yield reach the burning-plasma regime, hotspot ignition, and finally propagating burn and ignition. These implosions span a wide range of alpha heating from a yield amplification of 1.7-2.5. We show that the hotspot parameters are explicitly dependent on both yield and velocity and that by fitting to both of these quantities the hotspot parameters can be fit with a single power law in velocity. The yield scaling also enables the hotspot parameters extrapolation to higher yields. This is important as various degradation mechanisms can occur on a given implosion at fixed implosion velocity which can have a large impact on both yield and the hotspot parameters. The yield scaling also enables the experimental dependence of the hotspot parameters on yield amplification to be determined. The implosions reported have resulted in the highest yield (1.73×10^{16}±2.6%), yield amplification, pressure, and implosion velocity yet reported at the National Ignition Facility.

8.
J Card Surg ; 35(11): 3173-3175, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32740953

RESUMO

BACKGROUND: The current coronavirus (COVID-19) pandemic is associated with severe pulmonary and cardiovascular complications. CASE PRESENTATION: This report describes a young patient with COVID-19 without any comorbidity presenting with severe cardiovascular complications, manifesting with pulmonary embolism, embolic stroke, and right heart failure. CONCLUSION: Management with short-term mechanical circulatory support, including different cannulation strategies, resulted in a successful outcome despite his critical cardiovascular status.


Assuntos
COVID-19/complicações , Oxigenação por Membrana Extracorpórea , Insuficiência Cardíaca/terapia , Disfunção Ventricular Direita/terapia , Adulto , Embolectomia , AVC Embólico/terapia , AVC Embólico/virologia , Insuficiência Cardíaca/virologia , Humanos , Masculino , Embolia Pulmonar/cirurgia , Embolia Pulmonar/virologia , Trombose/terapia , Trombose/virologia , Disfunção Ventricular Direita/virologia
9.
Nature ; 581(7809): 396-400, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32461650

RESUMO

Molecular spectroscopy offers opportunities for the exploration of the fundamental laws of nature and the search for new particle physics beyond the standard model1-4. Radioactive molecules-in which one or more of the atoms possesses a radioactive nucleus-can contain heavy and deformed nuclei, offering high sensitivity for investigating parity- and time-reversal-violation effects5,6. Radium monofluoride, RaF, is of particular interest because it is predicted to have an electronic structure appropriate for laser cooling6, thus paving the way for its use in high-precision spectroscopic studies. Furthermore, the effects of symmetry-violating nuclear moments are strongly enhanced5,7-9 in molecules containing octupole-deformed radium isotopes10,11. However, the study of RaF has been impeded by the lack of stable isotopes of radium. Here we present an experimental approach to studying short-lived radioactive molecules, which allows us to measure molecules with lifetimes of just tens of milliseconds. Energetically low-lying electronic states were measured for different isotopically pure RaF molecules using collinear resonance ionisation at the ISOLDE ion-beam facility at CERN. Our results provide evidence of the existence of a suitable laser-cooling scheme for these molecules and represent a key step towards high-precision studies in these systems. Our findings will enable further studies of short-lived radioactive molecules for fundamental physics research.

10.
J Chem Phys ; 152(19): 194101, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-33687265

RESUMO

An application of the continuous transformation of the origin of the current density (CTOCD) scheme to constrain the diamagnetic induced charge current density (Jd) to be divergenceless is introduced. This results in a family of Jd fields perpendicular and proportional to both the gradient of the electron density and the external magnetic field. Since, in the limit of a complete basis set calculation, the paramagnetic component Jp also becomes divergenceless, we call this scheme CTOCD-DC (CTOCD for Divergenceless Components). CTOCD-DC allows for a topological characterization of both Jd and Jp in terms of their stagnation graphs. All stagnation graphs of Jd from CTOCD-DC contain the zero points of the gradient of the unperturbed electron density (∇ρ). In this way, an intimate topological relation between ρ and the diamagnetic current contribution is revealed. Numerical experiments exemplified by the case of LiNHF in point group symmetry C1 suggest that the corresponding paramagnetic current contributions Jp can show tendencies to accumulate pseudo-stagnation lines in proximity of some kind of the zero points of ∇ρ. Common zero points of ∇ρ and the total currents are exactly zero points of the mechanical momentum density.

11.
Int J Cardiol ; 293: 211-217, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31109778

RESUMO

BACKGROUND: In pulmonary arterial hypertension (PAH), right ventricular (RV) failure is the main cause of mortality. Non-invasive estimation of ventricular-vascular coupling ratio (VVCR), describing contractile response to afterload, could be a valuable tool for monitoring clinical course in children with PAH. This study aimed to test two hypotheses: VVCR by cardiac magnetic resonance (VVCRCMR) correlates with conventional VVCR by right heart catheterization (VVCRRHC) and both correlate with disease severity. METHODS AND RESULTS: Twenty-seven patients diagnosed with idiopathic and associated PAH without post-tricuspid shunt, who underwent RHC and CMR within 17 days at two specialized centers for pediatric PAH were retrospectively studied. Clinical functional status and hemodynamic data were collected. Median age at time of MRI was 14.3 years (IQR: 11.1-16.8), median PVRi 7.6 WU × m2 (IQR: 4.1-12.2), median mPAP 40 mm Hg (IQR: 28-55) and median WHO-FC 2 (IQR: 2-3). VVCRCMR, defined as stroke volume/end-systolic volume ratio was compared to VVCRRHC by single-beat pressure method using correlation and Bland-Altman plots. VVCRCMR and VVCRRHC showed a strong correlation (r = 0.83, p < 0.001). VVCRCMR and VVCRRHC both correlated with clinical measures of disease severity (pulmonary vascular resistance index [PVRi], mean pulmonary artery pressure [mPAP], mean right atrial pressure [mRAP], and World Health Organization functional class [WHO-FC]; all p ≤ 0.02). CONCLUSIONS: Non-invasively measured VVCRCMR is feasible in pediatric PAH and comparable to invasively assessed VVCRRHC. Both correlate with functional and hemodynamic measures of disease severity. The role of VVCR assessed by CMR and RHC in clinical decision-making and follow-up in pediatric PAH warrants further clinical investigation.


Assuntos
Cateterismo Cardíaco/métodos , Imagem Cinética por Ressonância Magnética/métodos , Hipertensão Arterial Pulmonar , Disfunção Ventricular Direita , Assistência ao Convalescente/métodos , Criança , Tomada de Decisão Clínica , Pesquisa Comparativa da Efetividade , Precisão da Medição Dimensional , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Hipertensão Arterial Pulmonar/complicações , Hipertensão Arterial Pulmonar/diagnóstico , Hipertensão Arterial Pulmonar/fisiopatologia , Índice de Gravidade de Doença , Disfunção Ventricular Direita/diagnóstico , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/fisiopatologia
12.
Int J Cardiol ; 287: 96-105, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31003793

RESUMO

INTRODUCTION: Right ventricular (RV) failure due to pressure load is an important determinant of clinical outcome in pulmonary hypertension, congenital heart disease and left ventricular failure. The last decades it has become clear that metabolic dysregulation is associated with the development of RV-failure. However, underlying mechanisms remain to be unraveled. Recently, disruption of intracardiac lipid content has been suggested as potential inducer of RV failure. In the present study, we used a rat model of RV-dysfunction and aimed to obtain insight in temporal changes in RV-function, -remodelling and -metabolism and relate this to RV lipid content. METHODS AND RESULTS: Male Wistar WU rats were subjected to pulmonary artery banding (n = 25) or sham surgery (n = 14) and cellular, hemodynamic and metabolic assessments took place after 2, 5 and 12 weeks. In this model RV dysfunction and remodelling occurred, including early upregulation of oxidative stress markers. After 12 weeks of pressure load, lipidomics revealed significant decreases of myocardial diglycerides and cardiolipins, driven by (poly-)unsaturated forms. The decrease of cardiolipins was driven by its most abundant form, tetralinoleoylcardiolipin. Mitochondrial capacity for fatty acid oxidation preserved, while the capacity for glucose oxidation increased. CONCLUSION: RV dysfunction due to pressure load, is associated with decreased intracardiac unsaturated lipids, especially tetralinoleoylcardiolipin. This was accompanied with preserved mitochondrial capacity regarding fatty acids oxidation, with increased capacity for glucose oxidation, and early activation of oxidative stress. We suggest that early interventions should be directed towards preservation of lipid availability as possible mean in order to prevent RV failure.


Assuntos
Ventrículos do Coração/metabolismo , Metabolismo dos Lipídeos/fisiologia , Miocárdio/metabolismo , Disfunção Ventricular Direita/fisiopatologia , Função Ventricular Direita/fisiologia , Pressão Ventricular/fisiologia , Remodelação Ventricular/fisiologia , Animais , Modelos Animais de Doenças , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Masculino , Miocárdio/patologia , Estresse Oxidativo , Ratos , Ratos Wistar , Disfunção Ventricular Direita/metabolismo , Disfunção Ventricular Direita/patologia
13.
Sci Adv ; 5(3): eaau7923, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30873429

RESUMO

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.

14.
J Pediatr Surg ; 54(9): 1755-1760, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30635129

RESUMO

BACKGROUND: Necrotizing enterocolitis (NEC) predominantly occurs in preterm infants (PT-NEC). In term neonates, NEC occurs more frequently when a congenital heart disease is present (CHDNEC). Our aim was to evaluate differences and similarities in disease characteristics of PT-NEC versus CHD-NEC. METHODS: In this retrospective case-control study we identified all CHD infants who developed NEC Bell's stage ≥2 in our center from 2004 to 2014. We randomly selected (1:2 ratio) PT-NEC infants from the same period. Biochemical and clinical variables were retrieved from patient files. RESULTS: We found 18 CHD-NEC infants and selected 36 PT-NEC infants (gestational age 28.3 [25-35.6] weeks vs. 38.6 [31.7-40.7] weeks). Postnatal age at onset was significantly lower in CHD-NEC patients (4 [2-24] vs. 11 [4-41] days, p < 0.001). Lowest pH levels were lower (7.21 [7.01-7.47] vs. 7.27 [6.68-7.39], p = 0.02), and highest CRP levels were higher (112.5 mg/L [5.0-425.0] vs. 66.0 [5.2-189.0], p = 0.05) in PT-NEC vs. CHD-NEC. Anatomic localisation of the disease differed: the colon was significantly more often involved in CHD-NEC versus PT-NEC (86% vs. 33%, p = 0.03). Mortality caused by NEC was not different (22% vs. 11%, p = 0.47). CONCLUSION: While outcome of NEC in both groups is similar, the predominant NEC localisation differed between CHD-NEC and PT-NEC patients. This suggests that both variants of the disease have a different underlying pathophysiological mechanism that predisposes different intestinal regions to develop NEC. TYPE OF STUDY: Retrospective Case-Control Study. LEVEL OF EVIDENCE: Level III.


Assuntos
Enterocolite Necrosante , Cardiopatias Congênitas , Doenças do Recém-Nascido/epidemiologia , Estudos de Casos e Controles , Enterocolite Necrosante/complicações , Enterocolite Necrosante/epidemiologia , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/epidemiologia , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Estudos Retrospectivos
15.
Phys Rev Lett ; 121(13): 135001, 2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-30312055

RESUMO

To reach the pressures and densities required for ignition, it may be necessary to develop an approach to design that makes it easier for simulations to guide experiments. Here, we report on a new short-pulse inertial confinement fusion platform that is specifically designed to be more predictable. The platform has demonstrated 99%+0.5% laser coupling into the hohlraum, high implosion velocity (411 km/s), high hotspot pressure (220+60 Gbar), and high cold fuel areal density compression ratio (>400), while maintaining controlled implosion symmetry, providing a promising new physics platform to study ignition physics.

16.
Rev Sci Instrum ; 89(4): 045112, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29716368

RESUMO

Modern momentum imaging techniques allow for the investigation of complex molecules in the gas phase by detection of several fragment ions in coincidence. For these studies, it is of great importance that the single-particle detection efficiency ε is as high as possible, as the overall efficiency scales with εn, i.e., the power of the number of detected particles. Here we present measured absolute detection efficiencies for protons of several micro-channel plates (MCPs), including efficiency enhanced "funnel MCPs." Furthermore, the relative detection efficiency for two-, three-, four-, and five-body fragmentation of CHBrClF has been examined. The "funnel" MCPs exhibit an efficiency of approximately 90%, gaining a factor of 24 (as compared to "normal" MCPs) in the case of a five-fold ion coincidence detection.

17.
Phys Rev Lett ; 119(5): 055002, 2017 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-28949748

RESUMO

Ion acoustic waves are found to be susceptible to at least two distinct decay processes. Which process dominates depends on the parameters. In the cases examined, the decay channel where daughter modes propagate parallel to the mother mode is found to dominate at larger amplitudes, while the decay channel where the daughter modes propagate at angles to the mother mode dominates at smaller amplitudes. Both decay processes may occur simultaneously and with onset thresholds below those suggested by fluid theory, resulting in the eventual multidimensional collapse of the mother mode to a turbulent state.

18.
J Hand Surg Eur Vol ; 42(4): 338-345, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28399788

RESUMO

The distal radioulnar joint allows the human to rotate the forearm to place the hand in a desired position to perform different tasks, without interfering with the grasping function of the hand. The ulna is the stable part of the forearm around which the radius rotates; the stability of the distal radioulnar joint is provided by the interaction between ligaments, muscles and bones. The stabilizing structures are the triangular fibrocartilage complex, the ulnocarpal ligament complex, the extensor carpi ulnaris tendon and tendon sheath, the pronator quadratus, the interosseous membrane and ligament, the bone itself and the joint capsule. The purpose of this review article is to present and illustrate the current understanding of the functional anatomy and pathomechanics of this joint.


Assuntos
Articulação do Punho/anatomia & histologia , Articulação do Punho/fisiologia , Antebraço , Humanos , Ligamentos Articulares/anatomia & histologia , Ligamentos Articulares/fisiologia , Pronação , Supinação , Tendões/anatomia & histologia , Tendões/fisiologia
19.
Dalton Trans ; 46(27): 8855-8860, 2017 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-28443884

RESUMO

Macroporous magnesium silicide monoliths were successfully prepared by a two-step synthesis procedure. The reaction of gaseous magnesium vapor with macro-/mesoporous silicon, which was generated from hierarchically organized meso-/macroporous silica by a magnesiothermic reduction reaction, resulted in monolithic magnesium silicide with a cellular, open macroporous structure. By adjusting the reaction conditions, such as experimental set-up, temperature and time, challenges namely loss of porosity or phase purity of Mg2Si were addressed and monolithic magnesium silicide with a cellular network builtup was obtained.

20.
J Chem Phys ; 146(2): 024306, 2017 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-28088152

RESUMO

Photoelectron circular dichroism refers to the forward/backward asymmetry in the photoelectron angular distribution with respect to the propagation axis of circularly polarized light. It has recently been demonstrated in femtosecond multi-photon photoionization experiments with randomly oriented camphor and fenchone molecules [C. Lux et al., Angew. Chem., Int. Ed. 51, 4755 (2012) and C. S. Lehmann et al., J. Chem. Phys. 139, 234307 (2013)]. A theoretical framework describing this process as (2+1) resonantly enhanced multi-photon ionization is constructed, which consists of two-photon photoselection from randomly oriented molecules and successive one-photon ionization of the photoselected molecules. It combines perturbation theory for the light-matter interaction with ab initio calculations for the two-photon absorption and a single-center expansion of the photoelectron wavefunction in terms of hydrogenic continuum functions. It is verified that the model correctly reproduces the basic symmetry behavior expected under exchange of handedness and light helicity. When applied to fenchone and camphor, semi-quantitative agreement with the experimental data is found, for which a sufficient d wave character of the electronically excited intermediate state is crucial.

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