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Orbital ordering below 30 K was previously observed in the ferromagnetic ${\text{YTiO}}_{3}$ compound both by polarized neutron diffraction (PND) and x-ray magnetic diffraction (XMD). In this paper we report a procedure for the joint refinement of a unique spin-density model based on both PND and XMD data. The distribution of the unpaired $3d$ electron of titanium is clearly seen on the magnetization density reconstructed by the maximum entropy method from the PND data collection at 5 K. The ${\text{Ti}}^{3+}$ $3d$ orbital populations obtained by joint model refinement are discussed in terms of the orbital ordering scheme. Small but significant magnetic moments on apical oxygen ${\text{O}}_{1}$ and yttrium atoms are found. The agreement between experimental and theoretical spin densities obtained using density functional theory is discussed.

The objective was to investigate women's perceptions and the perceived stress experience when undergoing surveillance mammography for benign lesions (ACR3, BI-RADS). A semi-prospective study was carried out on women with diagnosed "probably benign" breast abnormalities. It was a multicentric study from 1st March to 10th June 2002. The survey was performed at the first follow-up mammography and included questions about perceptions and perceived stress related to the follow-up experience. The response is analysed with chi-square test. Fifty women (35-75 years) answered the questionnaire. All women were satisfied with reception. The mammographies were painful (23 cases). Subsequent time seemed to be too long (seven cases) and they were anxious in 19 cases. Quality of life was spoiled (disturbed) (20 cases). Professional and social perturbations were not frequent (four cases). Speaking to a relative is frequent (39 cases), but patients were not satisfied with it (33 cases). Medical information was estimated (47 cases) but was not satisfactory (36 cases). The median of the stress scale is 4-5. There are two pickaxes, one at 2 (11 cases), the second at 5 (8 cases). "Low-stressed" women could have an avoidance coping. "High-stressed" women could use a helplessness- hopelessness coping strategy. Women reported a good and informative medical support and adequate comprehension of the short follow-up mammography. They were reassured by the medical care, but the evaluation of the stress level shows it to be high, probably due to the uncertainty of diagnosis.

International audience; An alternative method for reconstruction of three-dimensional momentum density from directional Compton profiles is proposed and successfully applied to theoretical data on magnesium oxide (with a random noise added). The method consists of obtaining a compact analytical model for the reconstructed (Formula presented) from the least-squares fit directly on the directional profiles. The result is compared, together with a standard numerical-based reconstruction, to the theoretical momentum density from which the profiles were calculated. © 1999 The American Physical Society.

International audience; The high-temperature superconducting cuprate La2−xSrxCuO4 (LSCO) shows several phases ranging from antiferromagnetic insulator to metal with increasing hole doping. To understand how the nature of the hole state evolves with doping, we have carried out high-resolution Compton scattering measurements at room temperature together with first-principles electronic structure computations on a series of LSCO single crystals in which the hole doping level varies from the underdoped (UD) to the overdoped (OD) regime. Holes in the UD system are found to primarily populate the O 2px /py orbitals. In contrast, the character of holes in the OD system is very different in that these holes mostly enter Cu d orbitals. High-resolution Compton scattering provides a bulk-sensitive method for imaging the orbital character of dopants in complex materials.

The objective was to investigate women's perceptions and the perceived stress experience when undergoing surveillance mammography for benign lesions (ACR3, BI-RADS). A semi-prospective study was carried out on women with diagnosed "probably benign" breast abnormalities. It was a multicentric study from 1st March to 10th June 2002. The survey was performed at the first follow-up mammography and included questions about perceptions and perceived stress related to the follow-up experience. The response is analysed with chi-square test. Fifty women (35-75 years) answered the questionnaire. All women were satisfied with reception. The mammographies were painful (23 cases). Subsequent time seemed to be too long (seven cases) and they were anxious in 19 cases. Quality of life was spoiled (disturbed) (20 cases). Professional and social perturbations were not frequent (four cases). Speaking to a relative is frequent (39 cases), but patients were not satisfied with it (33 cases). Medical information was estimated (47 cases) but was not satisfactory (36 cases). The median of the stress scale is 4-5. There are two pickaxes, one at 2 (11 cases), the second at 5 (8 cases). "Low-stressed" women could have an avoidance coping. "High-stressed" women could use a helplessness- hopelessness coping strategy. Women reported a good and informative medical support and adequate comprehension of the short follow-up mammography. They were reassured by the medical care, but the evaluation of the stress level shows it to be high, probably due to the uncertainty of diagnosis.

Inelastic x-ray scattering (IXS), complementary to other more established inelastic scattering probes, such as light scattering, electron scattering, and neutron scattering, is becoming an important experimental technique in the study of elementary excitations in condensed matters. Over the past decade, IXS with total energy resolution of few meV has been achieved, and is being used routinely in the study of phonon dispersions in solids and liquids as well as dynamics in disordered and biological systems. In the study of electronic excitations, IXS with total energy resolution on the order of 100 meV to 1 eV is gaining wider applications also. For example, IXS has been used to study collective excitations of valence electrons, single electron excitations of valence electrons, as well as core electron excitations. In comparison with the alternative scattering techniques mentioned above, IXS has several advantages. First, IXS probes the full momentum transfer range of the dielectric response of the sample, whereas light scattering is limited to very small momentum transfers, and electron scattering suffers the effects of multiple scattering at large momentum transfers. Second, since IXS measures the bulk properties of the sample it is not surface sensitive, therefore it does not require special preparation of the sample. The greater flexibility in sample conditions and environments makes IXS an ideal probe in the study of liquids and samples under extreme temperature, pressure, and magnetic field. Third, the tunability of synchrotron radiation sources enables IXS to exploit element specificity and resonant enhancement of scattering cross sections. Fourth, IXS is unique in the study of dynamics of liquids and amorphous solids because it can probe the particular region of energy-momentum transfer phase space, which is inaccessible to inelastic neutron scattering. On the other hand, the main disadvantages of IXS are the small cross sections and the strong absorption of x-rays in high Z elements.

An energy loss feature with energy transfer close to the anion-to-cation charge-transfer energy of NiO is observed in the inelastic-x-ray-scattering spectrum as the incident x-ray energy is tuned through the Ni K absorption edge of NiO. The inelastic-scattering cross section shows large resonant enhancement and strong incident energy dependence. These observations are interpreted using a configuration-interaction cluster model of NiO. \textcopyright{} 1996 The American Physical Society.

Ten French-American hybrid grapevine cultivars were evaluated for their reactions to four plant-parasitic nematodes : Criconemella xenoplax, Meloidogyne hapla, Pratylenchus penetrans, and Xiphinema americanum. In the spring of 1987, following soil fumigation, ownrooted vines of the cultivars Couderc 1202, Couderc 1616, Couderc 3309, Kober 5BB, Teleki 5A, Teleki 5C, Foch, Seyval, Vidal, and Vignoles were planted into microplots arranged in a completely randomized design with five replications per treatment. The microplots were inoculated with 2,500 M. hapla eggs, 2,500 juveniles and adults of the other three nematode species, or not inoculated. In 1989 and 1990, cane length was measured for each vine, and from 1991 to 1993, vine pruning weights and fruit yields were recorded. The experiment was terminated in the fall of 1993. At least one of the four species of nematodes reduced growth or yield of all the grapevine cultivars tested during 1 year of the study except for Couderc 1202. Yields of cv. Seyval were increased in the presence of all four species of nematodes in at least I year of the study, although vine pruning weight was reduced by M. hapla in 1993. In general, M. hapla was the most virulent of the nematodes studied. Meloidogyne hapla reduced fruit yields at least 1 year compared with the control plots in five of the seven cultivars from which yields were collected. Criconemella xenoplax only reduced yields of Foch, P. penetrans did not reduce yields of any cultivar, and X. americanum reduced yields of Vidal and Vignoles. This study should provide viticulturists with valuable information on nematode-grapevine cultivar interactions for management purposes.

A triple human catheter was used for the determination of cardiac output during the acute phase of moycardial infarction in 23 patients. The correlation coefficient between thermodilution and the Fick method was 0.91. Precision of the method assessed by multiple repeated determinations was 4.8 or 5.6%. Quadruplicate determinations allowed to detect variations of cardiac output in the range of 0.465 1/min. Variation between two successive determinations of more than 9.4% can probably be attributed to a technical error.

Intravenous mexiletine (250 mg in 10 min) given to patients at the acute stage of a myocardial infarction was responsible of a mild decrease of the left ventricular function; two of our patients presented bradycardia with hypotension, immediately corrected by atropine (i.v.). Adverse hemodynamic effects are seldom reported after oral administration.

The authors report a case of hypertension due to dysplasia of the renal arteries in a young man, and found the same disease in siblings. Two sisters and one brother also had renal hypertension, whereas the other relatives were unaffected. Two similar cases found in the world literature, did not permit the authors to determine the cause of this disease. This case is reported in order to stimulate research and the discovery of new cases.

Clinical safety and hemodynamic repercussions were studied after administration of six class I antiarrhythmics (xylocaine, ajmaline, mexiletine, lorcainide, indecainide and tocainide) to patients presenting acute myocardial infarction without complications. The hemodynamic parameters monitored generally followed the same trends. A significant decrease of more than 10 per cent of the initial value was seen in systolic blood flow after injection of lorcainide, indecainide and tocainide. Peripheral vascular resistance increased moderately. Pulmonary capillary pressure increased by more than 40 per cent of the starting value after administration of mexiletine, indecainide and tocainide (significant increase in case of mexiletine). These changes in patients presenting infarction without complications are not of clinical importance. There were, however, two very severe cases of hemodynamic reaction after administration of mexiletine. Other signs of intolerance were seen, but they were of minor importance and administration of the drugs was not interrupted. Xylocaine and ajmaline produced the smallest depression of left ventricular functional activity in these patients.

The authors describe 2 cases of Kearns-Sayre Syndrome associated with conduction defects. In one case permanent pacing was performed. The progressive development of severe conduction defects warrants close follow-up.

From this analysis of a series of 39 cases of trauma submitted to angiography, it can once again be said that surgical indications and tactics are essentially determined by vascular involvment. Renal arteriography is therefore alone capable of answering two primordial questions: "Must surgery be undertaken and when operating, what surgical tactics to adopt". It must be preceded by full arteriography which enables one to evaluate associated lesions (spleen 15%), at the same time as it orientates selective arteriography. The I.V.P. is a correct means of approach but is only significant in 60% of cases. Abstention from radiological investigation as a primary requisite is unpardonable and can leave irreversible sequels. (10% of cases).

Immunomodulators, whether natural (polysaccharides) or industrial (non-hemolytic detergents) proved active by themselves, in preventive or curative schemes of experimental leprosy and malaria. However, their activity was most often increased, through joint administration with chemotherapeutic agents.