Structural, magnetic and electronic properties of pulsed-laser-deposition grown SrFeO3-δ thin films and SrFeO3-δ /La2/3Ca1/3MnO3 multilayers

We studied the structural, magnetic and electronic properties of [Formula: see text] (SFO) thin films and [Formula: see text]/[Formula: see text] [Formula: see text]MnO₃ (LCMO) superlattices that have been grown with pulsed laser deposition (PLD) on [Formula: see text] [Formula: see text] [Formula: see text] [Formula: see text] [Formula: see text] (LSAT) substrates. X-ray reflectometry and scanning transmission electron microscopy (STEM) confirm the high structural quality of the films and flat and atomically sharp interfaces of the superlattices. The STEM data also reveal a difference in the interfacial layer stacking with a SrO layer at the LCMO/SFO and a LaO layer at the SFO/LCMO interfaces along the PLD growth direction. The x-ray diffraction (XRD) data suggest that the as grown SFO films and SFO/LCMO superlattices have an oxygen-deficient [Formula: see text] structure with I4/ mmm space group symmetry ([Formula: see text]). Subsequent ozone annealed SFO films are consistent with an almost oxygen stoichiometric structure ([Formula: see text]). The electronic and magnetic properties of these SFO films are similar to the ones of corresponding single crystals. In particular, the as grown [Formula: see text] films are insulating whereas the ozone annealed films are metallic. The magneto-resistance effects of the as grown SFO films have a similar magnitude as in the single crystals, but extend over a much wider temperature range. Last but not least, for the SFO/LCMO superlattices we observe a rather large exchange bias effect that varies as a function of the cooling field.

Strain-induced ferromagnetism in antiferromagnetic LuMnO3 thin films

Single phase and strained LuMnO(3) thin films are discovered to display coexisting ferromagnetic and antiferromagnetic orders. A large moment ferromagnetism (≈1μ(B)), which is absent in bulk samples, is shown to display a magnetic moment distribution that is peaked at the highly strained substrate-film interface. We further show that the strain-induced ferromagnetism and the antiferromagnetic order are coupled via an exchange field, therefore demonstrating strained rare-earth manganite thin films as promising candidate systems for new multifunctional devices.

Comprehensive comparison of various techniques for the analysis of elemental distributions in thin films

The present work shows results on elemental distribution analyses in Cu(In,Ga)Se2 thin films for solar cells performed by use of wavelength-dispersive and energy-dispersive X-ray spectrometry (EDX) in a scanning electron microscope, EDX in a transmission electron microscope, X-ray photoelectron, angle-dependent soft X-ray emission, secondary ion-mass (SIMS), time-of-flight SIMS, sputtered neutral mass, glow-discharge optical emission and glow-discharge mass, Auger electron, and Rutherford backscattering spectrometry, by use of scanning Auger electron microscopy, Raman depth profiling, and Raman mapping, as well as by use of elastic recoil detection analysis, grazing-incidence X-ray and electron backscatter diffraction, and grazing-incidence X-ray fluorescence analysis. The Cu(In,Ga)Se2 thin films used for the present comparison were produced during the same identical deposition run and exhibit thicknesses of about 2 μm. The analysis techniques were compared with respect to their spatial and depth resolutions, measuring speeds, availabilities, and detection limits.

Characterization of oxide films by MeV ion beam techniques

MeV ion beam techniques can provide highly quantitative compositional analysis of surfaces and thin layers. This quantitativeness is due to the very well known elastic nuclear scattering cross-sections of MeV particles. The most commonly used techniques are Rutherford backscattering spectrometry and elastic recoil detection analysis. Owing to the energy loss of ions in the material, whole compositional depth profiles can be obtained in a single short measurement almost nondestructively. The sensitivity to oxygen can be enhanced by the use of nuclear resonances or forward scattering techniques. State-of-the-art ion beam analysis can determine thin film stoichiometries with an accuracy of 1% and a depth resolution in the low nm range. An overview of the available techniques is given and illustrated with examples.

Abortifacient and endocrine effects of metergoline in beagle bitches during the second half of gestation

The purpose of this study was to investigate the abortifacient effects of high doses of metergoline when administered to pregnant beagle bitches during the second half of gestation and to define the endocrine effects of this treatment as represented by plasma progesterone and estradiol concentrations. Previously, metergoline had been shown to be incompletely luteolytic and induced abortion in only one of eight pregnant bitches when 0.4-0.5 mg/kg were administered twice daily for 5 days from Days 18 to 20 of diestrus. Nine pregnancies in six beagle bitches were used for the present study. Three bitches were treated in each of two consecutive pregnant cycles. Metergoline was administered at a dose of 0.6 mg/kg per os twice daily, starting on Day 28 after the cytological onset of diestrus. Abortion was induced in eight of the nine treated pregnancies and started after 3-23 days of treatment (mean 12.5 days, S.D. 6.4 days). The abortions were completed within 0.5-8 days (mean 2.2 days, S.D. 2.7 days). There were no side effects associated with metergoline treatment and none of the abortions was associated with complications that required intervention. In the single bitch that did not abort, an ovarian granulosa cell tumor was discovered when the single fetus had to be removed surgically at term. Plasma progesterone concentrations declined after the start of metergoline administration in all pregnancies but levels below 4.8 nmol/l were required for successful abortions. Plasma estradiol concentrations showed a tendency to decline and fluctuate concurrently with the plasma progesterone levels. However, suppression of plasma estradiol concentrations by metergoline was not as complete as the suppression of progesterone and did not seem a prerequisite for abortion. The hormone profiles and treatment period required for abortion tended to be similar for both cycles of the three bitches that were treated during two consecutive pregnancies. This suggests a bitch effect on the factors that determine the efficacy of metergoline to induce abortion. The large variation and length of the treatment period that was required until abortion commenced was probably related to the relatively early start of treatment compared to other studies. The results of this investigation suggest that, similar to other prolactin suppressing ergot derivatives, metergoline causes complete luteolysis and can be used to reliably induce abortion only during the last 3 weeks of gestation.

Effects of EDTA-induced hypocalcaemia and stress on plasma TNF-alpha, IL-1-ra, G-CSF, GM-CSF and S-100 in dairy cows

The pathophysiology of postparturient paresis is still not completely understood. Knowledge recently acquired in immunology, endocrinology and cell physiology has still to be integrated in order to elucidate the aetiopathogenesis of the disease. For that purpose, the effect of the EDTA infusion model on the plasma concentrations of selected cytokines and growth factors, and of a calcium binding protein was examined in dairy cows. Six 6- to 11-year-old Brown Swiss cows in mid lactation were infused with a 5% solution of Na2EDTA in one jugular vein over a period of 5 h. Blood samples were collected from the contralateral side daily two days before, and then hourly for five hours during the infusion, hourly for five hours after the end of the infusion, and once daily for 10 days thereafter. The plasma concentrations of cortisol, tumour necrosis factor-alpha, interleukin-1 receptor antagonist, granulocyte colony-stimulating factor, granulocyte and macrophage colony-stimulating factor, and the calcium binding protein S-100 were determined. Before the EDTA infusion, during the infusion and for two days thereafter, the mean plasma concentrations of cortisol were significantly higher than those from days 4 to 10 after the infusion. The plasma concentrations of tumour necrosis factor-alpha and interleukin-1 receptor antagonist followed a similar profile. At the end of EDTA infusion, low concentrations of granulocyte colony-stimulating factor were detected in one cow only. On days 3 and 4, the mean plasma concentrations of granulocyte colony-stimulating factor were significantly higher than the pre-infusion values, but this was followed by a significant decrease on post-infusion day 5. From day 4 to 7, the plasma concentrations of S-100 were significantly lower than the pre-infusion values. The importance of these findings in the pathophysiology of postparturient paresis remains to be established.

Physiological Responses to parental separation and a strange situation are related to parental care received in juvenile Goeldi's monkeys (Callimico goeldii)

The relationship between parental care received and physiological and behavioral responses to parental separation, isolation, and reunion was investigated in seven juvenile Goeldi's monkey living in their family groups. Physiological responses were measured non-invasively: the hypothalamic-pituitary-adrenal axis via urinary cortisol output and the autonomic nervous system via piloerection on the tail. Parent-infant aggression demonstrated high intergroup variation and predicted: (a) an increase in urinary cortisol output, r(s) = 0.86, p = 0.04, and duration of piloerection, r(s) = 0.71, p = 0.08, at initial separation-isolation; (b) adaptation of piloerection, r(s) = -0.89, p = 0.03, to repeated separation-isolation. Juvenile Goeldi's monkeys that had received high parental aggression were more physiologically responsive to separation; they also sought more contact with their mothers at reunion, rs = 0.93, p = 0.02. We propose that these data are consistent with the hypothesis that high emotional reactivity is related to insecure attachment to aggressive parents in this New world primate.

Evidence from urinary cortisol that maternal behavior is related to stress in gorillas

By studying western lowland gorillas (Gorilla gorilla gorilla, n = 8) in zoological gardens via ethological and non-invasive physiological techniques, we have demonstrated that their postpartum maternal behavior is related negatively to their postpartum urinary titers of cortisol. On the basis of this finding, it is proposed that postpartum stress contributes to disrupted maternal behavior in the gorilla in captivity. Morning urine samples were collected with a mean sampling interval of 1.6 days from Day 14 prepartum to Day 14 postpartum (n = 11 pregnancies). Creatinine-indexed (Cr) urinary cortisol titers declined significantly between Day 9 to 1 prepartum (0.634 +/- 0.014 microg/mg of Cr, mean +/- SEM) and Day 1 to 6 postpartum (0.396 +/- 0.030 microg/mg of Cr, mean +/- SEM; p < 0.01-0.001). For each pregnancy, the relative postpartum decline in urinary cortisol was calculated as (microg of cortisol/mg of Cr Day 1 to 4)/(microg of cortisol/mg of Cr Day -4 to -1). Values ranged from 0.35 to 1.12, were independent of absolute prepartum cortisol titers, and were interpreted as evidence of inter-female differences in postpartum hypothalamo-pituitary-adrenal axis activity and, therefore, postpartum stress. This postpartum stress index was negatively correlated with the amount of time (0-100%) that females carried and supported their 0-14 day-old infants in a ventral position during locomotion (r(s) = -0.68, p < 0.05) and tended to be negatively correlated with the total amount of time (0-100%) they spent in ventro-ventral contact with their infants (r(s) = -0.58; p < 0.10). This study provides the first physiological evidence that postpartum stress is an important etiologic factor in gorilla maternal failure in captive environments.

[Endocrinologic and pathologic findings in ornamental birds with polyostotic hyperostosis]

Polyostotic hyperostosis is a finding that is often seen on x-rays in companion birds. Hyperestrogenism might be a causative for polyostotic hyperostosis. The purpose of this study was to compare endocrinologic and pathologic findings in birds with polyostotic hyperostosis. Thirty-five affected and three control birds were examined. Blood samples were taken for endocrinologic statement (estrone, estradiol, testosterone and estrone sulfate) and the values were compared with the pathologic findings. In the present study the comparison of endocrinologic and pathologic findings did not reveal any significant results supporting the hypothesis that polyostotic hyperostosis was caused by hyperestrogenism.

An investigation into sexual motivation and behavior in female Goeldi's monkey (Callimico goeldii): effect of ovarian state, mate familiarity and mate choice

Four adult female Callimico were studied in terms of their sexual motivation relative to three unrelated adult males using an operant paradigm followed by a pair test or a two-male choice test. Reductions in urinary cortisol concentrations and the duration of immobility were used as indicators of subjects' adjustment to the experimental situation. When females were tested with unfamiliar males there was no effect of ovarian state on operant or species-typical measures of female sexual motivation. When females were retested with the same males after a 1-week familiarization, sexual motivation was higher during the peri-ovulatory phase than during the post-ovulatory phase in terms of operant but not in terms of species-typical proceptive behavior or in terms of receptive behavior. During the familiarization periods, female sociopositive behavior and sexual motivation demonstrated marked variation depending on the identity of the male. Males with which females demonstrated high sexual motivation during familiarization were the object of equal amounts of female operant behavior during pair tests and two-male choice tests; males with which females had demonstrated low sexual motivation were the objects of less female sexual motivation under conditions of female choice than in pair tests.

Comparative study of oestrogen excretion in female New World Monkeys: an overview of non-invasive ovarian monitoring and a new application in evolutionary biology

Oestrogen was measured in urine samples collected from captive females representing 7 species of New World monkey to provide an overview of the applicability of such formation in the noninvasive monitoring of ovarian function and to assess the potential applicability of such information in phylogenetic studies. Species available for study were the pygmy marmoset, common marmoset, red-bellied tamarin, cotton-top tamarin, golden lion tamarin, Goeldi's monkey and the owl monkey. Oestrone conjugates were measured in serially collected urine samples to demonstrate ovarian cyclicity. Urine samples obtained during the luteal phase were subjected to HPLC to identify immunoreactive oestrogens; oestrone and oestradiol-17 beta accounted for almost all of the immunoreactive oestrogen detected while oestriol content was negligible. Urine samples obtained during the follicular phase and luteal phase were subjected to glucuronidase hydrolysis, sulphatase hydrolysis and acid solvolysis, which revealed that the major immunoreactive oestrogen metabolite was: (1) oestradiol sulphate in the pygmy marmoset and common marmoset, (2) residual oestradiol in the red-bellied tamarin, (3) residual oestradiol and oestrone glucuronide in the cotton-top tamarin, and (4) oestrone glucuronide in the golden lion tamarin, Goeldi's monkey and owl monkey. A phylogenetic tree based on the above shifts in oestrogen excretion suggested that clawed New World monkeys are specialized and that the lineages leading to the study species split off in the following order: Goeldi's monkey, golden lion tamarin, cotton-top tamarin, red-bellied tamarin, common marmoset and pygmy marmoset.

Effects of sex steroids on maternal motivation in the common marmoset (Callithrix jacchus): development and application of an operant system with maternal reinforcement

We developed an operant paradigm for measuring effects of reproductive steroids on maternal motivation in common marmosets (Callithrix jacchus). Conditioned response regulated females' exposure to maternal reinforcement. Nulliparous females (n = 15) with experience with infants in social groups were subjects. The paradigm was validated by examining (a) effects of reinforcing stimuli on affective behavior in a nonoperant paradigm, (b) responsiveness of operant performance to changes in reinforcing stimuli and reinforcement schedule, (c) changes in operant responding due to omission of reinforcement, and (d) relation between operant responding and species-typical maternal behavior. In pregnant females, (n = 4), frequency of bar pressing and estradiol:progesterone ratio were maximal just before birth. Nonpregnant females (n = 3) treated with progesterone and estradiol to mimic late-pregnancy steroid profiles showed increased operant maternal behavior.